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Cunningham, James H. "Juxtaposed Integration Matrix a crisis communication tool /." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009781.
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Hoydis, Jakob. "Random matrix theory for advanced communication systems." Phd thesis, Supélec, 2012. http://tel.archives-ouvertes.fr/tel-00765458.
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Advanced mobile communication systems are characterized by a dense deployment of different types of wireless access points. Since these systems are primarily limited by interference, multiple-input multiple-output (MIMO) techniques as well as coordinated transmission and detection schemes are necessary to mitigate this limitation. Thus, mobile communication systems become more complex which requires that also the mathematical tools for their theoretical analysis must evolve. These must be able to take the most important system characteristics into account, such as fading, path loss, and interference. The aim of this thesis is to develop such tools based on large random matrix theory and to demonstrate their usefulness with the help of several practical applications, such as the performance analysis of network MIMO and large-scale MIMO systems, the design of low-complexity polynomial expansion detectors, and the study of random beamforming techniques as well as multi-hop relay and double-scattering channels. The methods developed in this work provide deterministic approximations of the system performance which become arbitrarily tight in the large system regime with an unlimited number of transmitting and receiving devices. This leads in many cases to simple and close approximations of the finite-size system performance and allows one to draw relevant conclusions about the most significant parameters. One can think of these methods as a way to provide a deterministic abstraction of the physical layer which substantially reduces the system complexity. Due to this complexity reduction, it is possible to carry out a system optimization which would be otherwise intractable.
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Khabou, Amal. "Dense matrix computations : communication cost and numerical stability." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00833356.
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Cette thèse traite d'une routine d'algèbre linéaire largement utilisée pour la résolution des systèmes li- néaires, il s'agit de la factorisation LU. Habituellement, pour calculer une telle décomposition, on utilise l'élimination de Gauss avec pivotage partiel (GEPP). La stabilité numérique de l'élimination de Gauss avec pivotage partiel est caractérisée par un facteur de croissance qui est reste assez petit en pratique. Toutefois, la version parallèle de cet algorithme ne permet pas d'atteindre les bornes inférieures qui ca- ractérisent le coût de communication pour un algorithme donné. En effet, la factorisation d'un bloc de colonnes constitue un goulot d'étranglement en termes de communication. Pour remédier à ce problème, Grigori et al [60] ont développé une factorisation LU qui minimise la communication(CALU) au prix de quelques calculs redondants. En théorie la borne supérieure du facteur de croissance de CALU est plus grande que celle de l'élimination de Gauss avec pivotage partiel, cependant CALU est stable en pratique. Pour améliorer la borne supérieure du facteur de croissance, nous étudions une nouvelle stra- tégie de pivotage utilisant la factorisation QR avec forte révélation de rang. Ainsi nous développons un nouvel algorithme pour la factorisation LU par blocs. La borne supérieure du facteur de croissance de cet algorithme est plus petite que celle de l'élimination de Gauss avec pivotage partiel. Cette stratégie de pivotage est ensuite combinée avec le pivotage basé sur un tournoi pour produire une factorisation LU qui minimise la communication et qui est plus stable que CALU. Pour les systèmes hiérarchiques, plusieurs niveaux de parallélisme sont disponibles. Cependant, aucune des méthodes précédemment ci- tées n'exploite pleinement ces ressources. Nous proposons et étudions alors deux algorithmes récursifs qui utilisent les mêmes principes que CALU mais qui sont plus appropriés pour des architectures à plu- sieurs niveaux de parallélisme. Pour analyser d'une façon précise et réaliste
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Cook, Christi Dionne. "Illuminating epithelial-stromal communication using engineered synthetic matrix microenvironments." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115753.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biological Engineering, 2018.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Mucosal barrier tissues are prominent targets for drugs against infection and chronic inflammatory disorders. One such mucosal barrier tissue, the endometrium, undergoes monthly cyclic remodeling via hormone-mediated growth, immune cell recruitment and proteolytic breakdown. Hormone response disruption has been associated with numerous endometrial pathologies, including endometriosis, adenomyosis, and infertility, which impacts upwards of 10% of women during their reproductive years. Currently, our understanding of endometrial biology is limited by the ability to replicate complex 3D physiology in vitro. Our ability to parse disease mechanisms and test efficacy of therapeutic interventions relies on development of reproducible models, adaptable to the limited numbers of cells available from patient biopsies. In this thesis, I address a critical gap in accessible tools to study and control endometrial biology in vitro and do so in a manner that can be translated to other epithelial-stromal mucosal tissues. Using the endometrium as an example mucosal barrier, I first establish design principles for the development of a synthetic, modular extracellular matrix (ECM) hydrogel suitable for 3D functional co-culture of epithelial and stromal cells. This 'one-size- fits-all' matrix features components that can be remodeled by cells and that responds dynamically to sequester local cell-secreted ECM characteristic of each cell type enabling long-term, hormonally responsive co-cultures. Next, I establish methods to expand and cryopreserve primary human endometrial epithelial cells, which maintain barrier and secretory function, further enabling studies using primary cells. Finally, we use data-driven network modeling of secreted proteins to understand how variation in cytokine signaling may alter hormone responsiveness and proteolytic remodeling in primary epithelial-stromal co-cultures. With the ability to create and parse more complex 3D tissue models using primary cells to recapitulate healthy and diseased states, we further enable basic understandings of disease pathologies and subsequent drug discovery efforts aimed at inflammation, wound healing and immune modulation.<br>by Christi Dionne Cook.<br>Ph. D.
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ZHOU, SIYUAN. "Finite Random Matrix Theory Analysis of Multiple Antenna Communication Systems." Doctoral thesis, Politecnico di Torino, 2015. http://hdl.handle.net/11583/2601779.
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Multiple-antenna systems are capable of providing substantial improvement to wireless communication networks, in terms of
data rate and reliability. Without utilizing extra spectrum or power resources, multiple-antenna technology has already been supported
in several wireless communication standards, such as LTE, WiFi and WiMax. The surging popularity and enormous prospect of
multiple-antenna technology require a better understanding to its fundamental performance over practical environments.
Motivated by this, this thesis provides analytical characterizations of several seminal performance measures in advanced multiple-antenna
systems. The analytical derivations are mainly based on finite dimension random matrix theory and a collection of novel random matrix theory
results are derived.
The closed-form probability density function of the output of multiple-input multiple-output (MIMO) block-fading channels is studied.
In contrast to the existing results, the proposed expressions are very general, applying for arbitrary number of antennas, arbitrary signal-to-noise
ratio and multiple classical fading models. Results are presented assuming two input structures in the system: the independent identical distributed
(i.i.d.) Gaussian input and a product form input. When the channel is fed by the i.i.d. Gaussian input, analysis is focused on the channel matrices
whose Gramian is unitarily invariant. When the channel is fed by a product form input, analysis is conducted with respect to two capacity-achieving
input structures that are dependent upon the relationship between the coherence length and the number of antennas. The mutual information
of the systems can be computed numerically from the pdf expression of the output. The computation is relatively easy to handle, avoiding the
need of the straight Monte-Carlo computation which is not feasible in large-dimensional networks.
The analytical characterization of the output pdf of a single-user MIMO block-fading channels with imperfect channel state information at the receiver
is provided. The analysis is carried out under the assumption of a product structure for the input. The model can be thought of as a perturbation
of the case where the statistics of the channel are perfectly known. Specifically, the average singular values of the channel are given, while the
channel singular vectors are assumed to be isotropically distributed on the unitary groups of dimensions given by the number of transmit and
receive antennas. The channel estimate is affected by a Gaussian distributed error, which is modeled as a matrix with i.i.d. Gaussian entries of
known covariance.
The ergodic capacity of an amplify-and-forward (AF) MIMO relay network over asymmetric channels is investigated. In particular, the source-relay
and relay-destination channels undergo Rayleigh and Rician fading, respectively. Considering arbitrary-rank means for the relay-destination channel,
the marginal distribution of an unordered eigenvalue of the cascaded AF channel is presented, thus the analytical expression of the ergodic capacity
of the system is obtained. The results indicate the impact of the signal-to-noise ratio and of the Line-of-Sight component on such asymmetric
relay network.
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Srikanthan, Sasiharan Sudeshna. "An investigation of matrix switching topologies and algorithms." Thesis, University of Hertfordshire, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315633.
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Hewitt, James. "Using matrix training procedures to develop spontaneous and functional symbol communication." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294707.
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Ost, Alexander. "Performance of communication systems : a model-based approach with matrix-geometric methods /." New York : Springer, 2001. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=354041438X.
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Røsdal, Trude. "Leadership and leadership communication in a matrix structured organization : some critical factors." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-763.
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<p>This case study has shown how nearly every success and failure in the matrix structured Segment X was a result of leadership behaviour. If Project I was to be an unreserved success every leader on every level had to succeed in their efforts. After having interviewed employees and leaders, and observed several meetings the overall impression was of a well-functioning, mature matrix organization. However, it is not correct to say that Project I was an unreserved success. There were some areas within the matrix structure that appeared to be more troublesome than others. After having examined each of the seven related research questions the main research question should be answered: What constitutes an effective Norwegian matrix organization in terms of communication and leadership as perceived by its members/employees? In order for a leader in the matrix organization to succeed on a general level, it was perceived that he or she should be emotionally intelligent and possess social and communication skills. Communication skills that in particular were suggested to be of great importance were the ability to create a sense of commitment to organizational goals in each employee, and to be able to persuade the employees to reach set goals in time. Employees increasingly no longer ask “What should I do?” but “Why should I do it?”, and persuasion seemed in fact to be one of the more difficult aspects for the leaders of Segment X. Extensive interpersonal and communication skills were also perceived to be of great importance to meet the challenges of the matrix structure. The main challenge associated with the matrix structure was the distribution of resources. In order to handle this challenge in an effective way and avoid conflicts, respect for the current rules was pointed to as crucial by both functional and project leaders.</p><p>In general the most obvious challenge for Segment X and in particular Project I was the teams and the management of teams. The two teams of special interest in this case study experienced some serious problems. Team management and the composition of the teams were the main reasons that the teams struggled. Both these issues will be the responsibility of the functional management. Thus in a matrix structured organization where the use of work teams is necessary it is of great importance to in a more thorough way evaluate both the skills and style of the potential team leader and also consider the composition of the team. Since teams actually carry out the projects of the matrix organization, the effectiveness of the matrix organization is more or less dependent on well functioning teams.</p><p>The truly effective matrix organization is constituted first of all of socially skilled leaders on all levels who are effective persuaders, who are willing to respect the formal rules of the matrix structured organization, and who are able to alter their leadership style depending on the context. All this highlights the importance of and need for a stronger focus on leader communication and behaviour.</p><p>The results from this case study conducted in a Norwegian organization do not differ to any great extent from the findings of other relevant studies conducted in other countries (the literature reviewed in this thesis is mainly from English speaking countries). However, it does seem like the Norwegian organization (Segment X), and in particular in relation to Project I (as Project I formed the basis for this study) is a well functioning matrix organization, that has stared clear of some of the most obvious challenges mentioned by other research into matrix organizations. For instance the multiple reporting relationships that exist within a matrix organization were not mentioned to any great extent, neither by the leaders nor by the employees of Segment X.</p><p>In relation to further or future research within the area of organizational structure, leadership and leadership communication, several suggestions can be made. For this organization in particular it would be of value to conduct more research into the use of teams. As the teams are so important in a matrix structured organization like Segment X, more knowledge should be gained about the factors that will impact on the effectiveness of the team. One other question that could be raised is whether the necessary leadership skills and leadership communication will differ within a production oriented company compared to an innovation oriented company.</p><p>It is also of interest to be able to discuss why or if there are differences between a Norwegian matrix organization in terms of leadership and leadership communication, and matrix organizations in other countries. Future research will also benefit from using both qualitative and quantitative approaches, maybe especially in relation to investigate how communication skills of leaders are related to the feeling of commitment in the employees.</p>
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Ost, Alexander. "Performance of communication systems : a model based evaluation with matrix geometric methods /." Berlin ; Heidelberg [u.a.] : Springer, 2001. http://swbplus.bsz-bw.de/bsz090497023inh.htm.
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Massagli, Sérgio Roberto. "Em busca do espaço perdido em Matrix : do terrorismo teórico à violência simbólica /." Bauru : [s.n.], 2005. http://hdl.handle.net/11449/89440.
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Orientador: Nelyse Apparecida Melro Salzedas<br>Banca: Antonio Carlos de Jesus<br>Banca: Valdevino Soares de Oliveira<br>Resumo: O objetivo deste trabalho é mostrar como Matrix é o exemplo mais representativo do que se costuma chamar de filme de ficção cyberpunk e como o filme expõe e propõe como matéria conceitual básica o acesso a um novo topos, ou melhor, um u-topos, um não-espaço, também chamado de hiperespaço. No filme, um espaço para onde nossa subjetividade foi transportada e escravizada, enquanto nossos corpos jazem dóceis, subjugados e adormecidos em úteros mecânicos, sendo alimentados por cordões umbilicais metálicos. Trata-se de uma nova espacialidade, espelhada em nosso mundo contemporâneo, com a qual podemos nos relacionar através de alguma interface, em que fatos e coisas são-nos reapresentados a partir da simulação de um tempo real , que supõe um outro espaço-tempo social, de um novo tipo, espaço de auto-representação social imaterialmente fundada na existência de eventos gerados por técnicas digitais. Assim, partindo do pressuposto de que vivemos numa sociedade pós-moderna e da premissa de que, com o fim do Modernismo, a experiência do tempo e da subjetividade cedeu lugar à experiência pós-moderna do espaço, a preocupação que estará à frente de todas as outras neste trabalho será a de localizar no filme Matrix processos que reflitam as formas de apropriação espacial dessa mesma sociedade. A questão do espaço, enquanto conceito clássico, kantiano, de categoria universal dada a priori, que emoldura mesmo a experiência, será substituída por outra, que introduz a idéia de espaço enquanto diferentes formas de experimentar o real... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The goal of this work is to demonstrate how Matrix is the most representative example of what has been called cyberpunk fiction movie and how it reveals and propose as a basic conceptual issue the access to a new topos, or better saying, to a u-topos, a nonspace, also called cyberspace. In the movie, a space where our subjectivity was displaced to and enslaved, whereas our bodies rest docile, subjugated and sleeping in mechanical wombs, being fed through metallic umbilical lace. It s a new special dimension, mirrored on our contemporary world, with which we can relate by means of some interface and in which facts and objects are re-presented to us from the perspective of the simulation of a real time that elicits another social time-space, a dimension of self-representation socially and materially founded on the existence of technically generated events. Thus, from the premisse that we live in a postmodern society and that, once Modernism is over, the postmodern experience of time and subjectivity has yielded to the postmodern experience of space, the main concern during this work will be to locate in the film processes that reflect the appropriation of space within this society. The issue of space, as a classical, Kantian concept, of a universal category that frame the experience, will be replaced by another, which introduces the idea of space as different forms of experiencing the real. Space will be approached as a cultural concept that can be formulated in basis of forms of appropriation self-organized between two ends: power and resistance, which, in a reductionist way, can be understood in terms of virtual and real space, respectively... (Complete abstract, click electronic address below)<br>Mestre
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Massagli, Sérgio Roberto [UNESP]. "Em busca do espaço perdido em Matrix: do terrorismo teórico à violência simbólica." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/89440.
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massagli_sr_me_bauru.pdf: 1536916 bytes, checksum: 1bba9694c744b08cd501ec8dab24ffc6 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O objetivo deste trabalho é mostrar como Matrix é o exemplo mais representativo do que se costuma chamar de filme de ficção cyberpunk e como o filme expõe e propõe como matéria conceitual básica o acesso a um novo topos, ou melhor, um u-topos, um não-espaço, também chamado de hiperespaço. No filme, um espaço para onde nossa subjetividade foi transportada e escravizada, enquanto nossos corpos jazem dóceis, subjugados e adormecidos em úteros mecânicos, sendo alimentados por cordões umbilicais metálicos. Trata-se de uma nova espacialidade, espelhada em nosso mundo contemporâneo, com a qual podemos nos relacionar através de alguma interface, em que fatos e coisas são-nos reapresentados a partir da simulação de um tempo real , que supõe um outro espaço-tempo social, de um novo tipo, espaço de auto-representação social imaterialmente fundada na existência de eventos gerados por técnicas digitais. Assim, partindo do pressuposto de que vivemos numa sociedade pós-moderna e da premissa de que, com o fim do Modernismo, a experiência do tempo e da subjetividade cedeu lugar à experiência pós-moderna do espaço, a preocupação que estará à frente de todas as outras neste trabalho será a de localizar no filme Matrix processos que reflitam as formas de apropriação espacial dessa mesma sociedade. A questão do espaço, enquanto conceito clássico, kantiano, de categoria universal dada a priori, que emoldura mesmo a experiência, será substituída por outra, que introduz a idéia de espaço enquanto diferentes formas de experimentar o real...<br>The goal of this work is to demonstrate how Matrix is the most representative example of what has been called cyberpunk fiction movie and how it reveals and propose as a basic conceptual issue the access to a new topos, or better saying, to a u-topos, a nonspace, also called cyberspace. In the movie, a space where our subjectivity was displaced to and enslaved, whereas our bodies rest docile, subjugated and sleeping in mechanical wombs, being fed through metallic umbilical lace. It s a new special dimension, mirrored on our contemporary world, with which we can relate by means of some interface and in which facts and objects are re-presented to us from the perspective of the simulation of a real time that elicits another social time-space, a dimension of self-representation socially and materially founded on the existence of technically generated events. Thus, from the premisse that we live in a postmodern society and that, once Modernism is over, the postmodern experience of time and subjectivity has yielded to the postmodern experience of space, the main concern during this work will be to locate in the film processes that reflect the appropriation of space within this society. The issue of space, as a classical, Kantian concept, of a universal category that frame the experience, will be replaced by another, which introduces the idea of space as different forms of experiencing the real. Space will be approached as a cultural concept that can be formulated in basis of forms of appropriation self-organized between two ends: power and resistance, which, in a reductionist way, can be understood in terms of virtual and real space, respectively... (Complete abstract, click electronic address below)
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Girnyk, Maksym. "A Statistical-Physics Approach to the Analysisof Wireless Communication Systems." Doctoral thesis, KTH, Kommunikationsteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149868.
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Multiple antennas at each side of the communication channel seem to be vital for future wireless communication systems. Multi-antenna communication provides throughput gains roughly proportional to the smallest number of antennas at the communicating terminals. On the other hand, multiple antennas at a terminal inevitably increase the hardware complexity of the latter. For efficient design of such systems relevant mathematical tools, capable of capturing the most significant features of the wireless multi-antenna channel - such as fading, spatial correlation, interference - are essential. This thesis, based on the asymptotic methods from statistical physics and random matrix theory, develops a series of asymptotic approximations for various metrics characterizing the performance of multi-antenna systems in different settings. The approximations become increasingly precise as the number of antennas at each terminal grows large and are shown to significantly simplify the performance analysis. This, in turn, enables efficient performance optimization, which would otherwise be intractable. After a general introduction, provided in Chapter 2, this thesis provides four different applications of large-system analysis. Thus, Chapter 3 analyzes multi-antenna multiple-access channel in the presence of non-Gaussian interference. The obtained large-system approximation of the sum rate is further used to carry out the precoder optimization routine for both Gaussian and finite-alphabet types of inputs. Meanwhile, Chapter 4 carries out the large-system analysis for a multi-hop relay channel with an arbitrary number of hops. Suboptimality of some conventional detectors has been captured through the concept of generalized posterior mean estimate. The obtained decoupling principle allows performance evaluation for a number of conventional detection schemes in terms of achievable rates and bit error rate. Chapter 5, in turn, studies achievable secrecy rates of multi-antenna wiretap channels in three different scenarios. In the quasi-static scenario, an alternating-optimization algorithm for the non-convex precoder optimization problem is proposed. The algorithm is shown to outperform the existing solutions, and it is conjectured to provide a secrecy capacity-achieving precoder. In the uncorrelated ergodic scenario, a large-system analysis is carried out for the ergodic secrecy capacity yielding a closed-form expression. In the correlated ergodic scenario, the obtained large-system approximation is used to address the corresponding problem of precoder optimization. Finally, Chapter6 addresses a practical case of random network topology for two scenarios: i) cellular mobile networks with randomly placed mobile users and ii) wiretap channel with randomly located eavesdroppers. Large-system approximations for the achievable sum rates are derived for each scenario, yielding simplified precoder optimization procedures for various system parameters.<br><p>QC 20140901</p>
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Delport, Barend Petrus Johannes. "Vergelyking van kommunikasiebehoeftes by werknemers en bestuur op 'n Platinamyn." Thesis, Pretoria : [s.n.], 2001. http://upetd.up.ac.za/thesis/available/etd-05242002-151354.
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Berg, Miguel. "Radio Resource Management in Bunched Personal Communication Systems." Doctoral thesis, KTH, Signals, Sensors and Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3316.
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<p>The traditional way of increasing capacity in a wirelesscommunication system has been cell splitting and fixedchannel-allocation based on prediction tools. However, theplanning complexity increases rapidly with the number of cellsand the method is not suitable for the large temporal andspatial traffic variations expected in the future. A lot ofresearch has therefore been performed regarding adaptivechannel allocation, where a channel can be used anywhere aslong as the signal-to-interference ratio (SIR) is acceptable. Acommon opinion is that these solutions must be decentralizedsince a centralized one would be overly complex.</p><p>In this thesis, we study the locally centralized<i>bunch concept</i>for radio resource management (RRM) in aManhattan environment and show that it can give a very highcapacity both for outdoor users and for indoor users covered byoutdoor base stations. We show how measurement limitations anderrors affect the performance and wepropose methods to handlethese problems, e.g. averaging of measured values, robustchannel selection algorithms, and increased SIR margins. Wealso study the computational and signaling complexities andshow that they can be reduced by splitting large bunches, usingsparse matrix calculations, and by using a simplified admissionalgorithm. However, a reduction of the complexity often means areduction of the system capacity.</p><p>The measurements needed for RRM can also be used to find amobile terminal's geographical position. We propose and studysome simple yet accurate methods for this purpose. We alsostudy if position information can enhance RRM as is oftensuggested in the literature. In the studied scenario, thisinformation seems to be of limited use. One possible use is toestimate the mobile user's speed, to assist handover decisions.Another use is to find the location of user hotspots in anarea, which is beneficial for system planning.</p><p>Our results show that the bunch concept is a promisingcandidate for radio resource management in future wirelesssystems. We believe that the complexity is manageable and themain price we have to pay for high capacity is frequentreallocation of connections.</p><p><b>Keywords:</b>bunch concept, radio resource management,network-assisted resource management, base station selection,dynamic channel allocation, DCA, channel selection,least-interfered, interference avoidance, interferenceaveraging, handover, power control, path-loss measurements,signal strength, link-gain matrix, TD-CDMA, UTRA TDD, Manhattanscenario, microcells, mobile positioning, position accuracy,trilateration, triangulation, speed estimation</p>
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Tonsing, Kerstin Monika. "Using a matrix strategy to teach graphic symbol combinations to children with limited speech during shared storybook reading." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/25518.
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Children with limited speech using graphic symbols for communication often express themselves predominantly through single symbols rather than symbol combinations. This study aimed to investigate the effect of an intervention strategy that was incorporated into shared storybook reading on the production of graphic symbol combinations. Three children between the ages of 7;9 (years;months) and 10;8 with limited speech and physical impairments participated in the study. A multiple probe design across behaviours (3 different types of semantic symbol combinations) was used, replicated across the 3 participants. Intervention entailed prompting the production of strategic symbol combinations (generated from a matrix) during shared storybook reading by using a prompting hierarchy. The participants’ production of combinations targeted during intervention as well as their ability to generalize to nontarget combinations from the matrix was monitored using a probe test (picture description task). All 3 participants showed some gains in acquiring the combinations and generalizing to nontarget combinations, as measured by the probe test. While 1 participant showed convincing effects, the other 2 showed lower effects. Lower effects may be partly ascribed to participant characteristics as well as to the discrepancies between the intervention and probe contexts. All participants performed better within the shared storybook reading context. Results suggest that the production of symbol combinations can be facilitated during shared storybook reading and that the matrix strategy promotes generalization to untrained semantic combinations. However, participant gains may not reflect immediately in formal testing situations.<br>Thesis (PhD)--University of Pretoria, 2012.<br>Centre for Augmentative and Alternative Communication (CAAC)<br>unrestricted
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White, Kirrily. "From Trypillia to Tswana: A Global Perspective on Giant Low-Density Settlements." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28688.
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Giant settlements worldwide which incorporated large amounts of open space, such as Cahokia, Great Zimbabwe and the European oppida, have long seemed anomalous to scholarship because they did not match the characteristics of conventional urbanism. It is now apparent that these settlements appeared relatively frequently in diverse conditions across the world over the past 7000 years and they may constitute a form of human settlement behaviour that has not yet been consistently articulated. In Limits of Settlement Growth, Roland Fletcher (1995) identified that such settlements sit outside usual categories for specifying conditions of settlement operation in the past. He predicted that these settlements would have dropped to a low-density internal pattern as they expanded to large size. In his parlance they operated below a Threshold Limit on the Interaction-Communication Matrix and would not therefore be constrained in their areal expansion.
The aim of this research was to test Fletcher’s prediction for these sites in the I-C Model and explore the findings to delineate boundary conditions of their operation. A dataset of sites 100 ha or larger was compiled and compared across variables such as area, population mobility, durations and demise. Using a recently updated version of the I-C Matrix, these settlements were found to have operated beneath the Mobile Interaction-Limit as well as at lower densities. The mobility component of their operation varied substantially and there may be more than one type of human settlement behaviour indicated. Structurally, they were giant variants of preceding and contemporaneous settlement forms emergent under conditions of regional or sub-regional population increase rather than transformations. While individually they could have short durations, they could appear multiple times in a culture region and were resilient to all but regional systemic change.
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Tiger, Carl-Fredrik. "Cellular Interactions with Extracellular Matrix During Development and in Muscle Disease." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2002. http://publications.uu.se/theses/91-554-5328-7/.
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Styf, Emma. "Visual Communication between Truck Drivers and the Surroundings : - A Master’s Thesis Project for Increasing Communication and Reducing Accidents between HGV and VRUs." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69786.
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In recent years, accidents between trucks and other vehicles have decreased while accidents be-tween trucks and vulnerable road-users have increased. The reason for this is unknown, which is why this Master’s Thesis project was initiated. The project is a co-operation between two students from two different universities, LTU and KTH, done for Volvo GTT in Gothenburg. A user study containing interviews and co-rides has been executed with truck drivers in the Gothenburg area during the autumn of 2017. A survey was also sent to different organizations for cyclists, motorcyclists, car drivers and to Facebook groups for the two universities. Critical situations mentioned by the truck drivers were chosen with the help of the survey answers from other road-users. Right hand turns with a truck that crosses a bike lane and intersections with a zebra crossing were the situations the project focused on, based on the Volvo Trucks Safety Report 2017 which stated those situations as the most dangerous. Serious accidents occurring when a truck turns right is when vulnerable road-users end up under the truck’s back wheels, which cuts corners. This made the project focus on trying to find a solution that could reduce this type of accident. The project also concentrated on increasing the commu-nication at intersections, based on the survey comments where it became clear that eye contact is insufficient, which led to focus on communication between trucks and fellow road-user instead. Through benchmarking, literature reviews and idea generation the final concept solution was cre-ated and developed after a workshop. The final concept solution is a turning projection that visualizes the dangerous area when a truck is turning and a light matrix in the front grille for increasing the understanding, visually, of the truck driver’s intentions of slowing down or speeding up. The final concept solution contains a zebra crossing projection in the front of the truck to facilitate the communication today, and in the future to even replace eye contact and gestures done between truck driver and fellow road-users at crossings. Further development of the concept solution includes choices and adaption of available technology and research concerning legislation for color usage on lights and projections to the front and sides of the trucks.
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Xavier, Dominic Michael. "Development of a large scale flexible LED display matrix for the screen industry." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/62065/1/Dominic_Xavier_Thesis.pdf.
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This project addresses the viability of lightweight, low power consumption, flexible, large format LED screens. The investigation encompasses all aspects of the electrical and mechanical design, individually and as a system, and achieves a successful full scale prototype. The prototype implements novel techniques to achieve large displacement colour aliasing, a purely passive thermal management solution, a rapid deployment system, individual seven bit LED current control with two way display communication, auto-configuration and complete signal redundancy, all of which are in direct response to industry needs.
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Kopp, James Clayton, and Robert S. Kaplan. "The influence of organizational hierarchy and departmental structure on communication : the case of Kaplan and Norton's Balanced scorecard in a matrix organization." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59254.
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Thesis (S.M. in System Design and Management)--Massachusetts Institute of Technology, Engineering Systems Division, 2010.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 80-81).<br>A large business requires efficient and effective internal communication among employees to achieve its goals. Dodds, Watts, and Sable (DWS) introduced a communication network model assessing information flow within a business by examining the relative influences of organizational structure, message volatility, and task decomposability on the probability of successful message transmission, but there is no research available that examines this or similar models in the context of a real business. The model predicts optimal message flow in a "Multi-scale" organizational network, a structure which in practice may most resemble a matrix organization. In this study a survey was designed to measure the influence of rank and department on message transfer - particularly the informational attributes of understanding, accuracy, importance, and influenceability - originating from the Balanced Scorecard in a large, matrix-managed aerospace business. The survey data indicated the following results: - Understanding (of the Balanced Scorecard metrics) was significantly influenced by employee rank and exhibited some effects of departmental expertise with certain metrics. - Belief in the accuracy of the metrics correlated highly with Understanding. - Importance rankings of the metric displayed high alignment across both rank and department, an encouraging result for company management. - Influenceability (people's belief they could affect the metric) was heavily influenced by rank and somewhat influenced by department. It also generally exhibited the lowest levels and highest variation when compared to the other attributes. - A deeper analysis comparing the Engineering and Program Office departments revealed consistently better vertical communication for Engineering, and better lateral communication within ranks for Program Office, which may indicate an additional influence of department culture on information flow. When subjected to a DWS interpretation, the survey results provided clues about relative influences of rank and department on message flow and relative values of other DWS model parameters - task decomposability and message traffic volume - could be gleaned from employee comments and post-survey interviews. The study falls short of making absolute characterizations of the DWS attributes, but is able to make inferences regarding the communication of the separate attributes relative to each other. Indeed, one important implication of the work done here to DWS theory is that for different business concerns and for different organizations within the overall company, there are apparently different mappings onto the DWS communication framework. Analysis of the study data for this organization indicates lateral communication may be better than vertical communication for Understanding and Influenceability; Accuracy does not exhibit dominance by either parameter; and Importance is well communicated laterally and vertically. More empirical data on measurable information traffic such as email is needed from different organizations, industries, and national cultures for DWS parameter values to converge upon more absolute values.<br>by James Clayton Kopp.<br>S.M.in System Design and Management
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Petersson, Lantz Robert, and Andreas Alvarsson. "Creating access control maps and defining a security policy for a healthcare communication system." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121131.
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This report handles the creation of an access control map and the dening of asecurity policy for a healthcare communication system. An access control mapis a graphical way to describe the access controls of the subjects and objects ina system. We use a three step method to produce a graphical overview of theparts in the system, the interactions between them and the permissions of thesubjects. Regarding the security policy we create a read up and read down policylike the so called Ring policy, but adapt a write sideways approach. We alsoapply a mandatory access control which has a centralized authority that denesthe permissions of the subjects. Attribute restrictions is also included to thesecurity levels, to set an under limit for reading permissions.
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Anderson, Norman Dale. "A study to measure the affect [sic] of reciprocal self-disclosure in a small group matrix on the sense of intimacy and individuality." Theological Research Exchange Network (TREN), 2005. http://www.tren.com.
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Flegar, Goran. "Sparse Linear System Solvers on GPUs: Parallel Preconditioning, Workload Balancing, and Communication Reduction." Doctoral thesis, Universitat Jaume I, 2019. http://hdl.handle.net/10803/667096.
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With the breakdown of Dennard scaling in the mid-2000s and the end of Moore's law on the horizon, the high performance computing community is turning its attention towards unconventional accelerator hardware to ensure the continued growth of computational capacity. This dissertation presents several contributions related to the iterative solution of sparse linear systems on the most widely used general purpose accelerator - the Graphics Processing Unit (GPU). Specifically, it accelerates the major building blocks of Krylov solvers, and describes their realization as part of a software library of reusable building blocks. The first part of the dissertation focuses on the sparse matrix-vector product and effective load balancing in the presence of irregular sparsity patterns. The second part describes the design of high-performance preconditioners. Finally, the third part demonstrates the potential of adaptive precision techniques for constructing preconditioners with lower memory footprint, and accuracy comparable to their full precision equivalents.<br>Con el final de la ley de Dennard y el cercano fin de la ley de Moore, la comunidad en computación de altas prestaciones se está centrando en tecnologías de aceleración no convencionales para asegurar el crecimiento exponencial de la capacidad de computación. Esta tesis contribuye a la solución iterativa de sistemas lineales dispersos en el acelerador más difundido: el procesador gráfico. Específicamente, el trabajo acelera los bloques fundamentales de los métodos de Krylov, y describe su implementación como parte de una biblioteca de bloques reutilizables. La primera parte del trabajo se centra en el producto matriz-vector disperso y el equilibrado de la carga ante patrones de dispersidad irregulares. La segunda parte describe el diseño de precondicionadores de alto rendimiento. Finalmente, la tercera parte demuestra el potencial de las técnicas de precisión adaptativa para construir precondicionadores con menor consumo de memoria, y fiabilidad comparable con las versiones de precisión completa.
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Couillet, Romain. "Application of random matrix theory to future wireless flexible networks." Phd thesis, Supélec, 2010. http://tel.archives-ouvertes.fr/tel-00808022.
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Future cognitive radio networks are expected to come as a disruptive technological advance in the currently saturated field of wireless communications. The idea behind cognitive radios is to think of the wireless channels as a pool of communication resources, which can be accessed on-demand by a primary licensed network or opportunistically preempted (or overlaid) by a secondary network with lower access priority. From a physical layer point of view, the primary network is ideally oblivious of the existence of a co-localized secondary networks. The latter are therefore required to autonomously explore the air in search for resource left-overs, and then to optimally exploit the available resource. The exploration and exploitation procedures, which involve multiple interacting agents, are requested to be highly reliable, fast and efficient. The objective of the thesis is to model, analyse and propose computationally efficient and close-to-optimal solutions to the above operations.Regarding the exploration phase, we first resort to the maximum entropy principle to derive communication models with many unknowns, from which we derive the optimal multi-source multi-sensor Neyman-Pearson signal sensing procedure. The latter allows for a secondary network to detect the presence of spectral left-overs. The computational complexity of the optimal approach however calls for simpler techniques, which are recollected and discussed. We then proceed to the extension of the signal sensing approach to the more advanced blind user localization, which provides further valuable information to overlay occupied spectral resources.The second part of the thesis is dedicaded to the exploitation phase, that is, the optimal sharing of available resources. To this end, we derive an (asymptotically accurate) approximated expression for the uplink ergodic sum rate of a multi-antenna multiple-access channel and propose solutions for cognitive radios to adapt rapidly to the evolution of the primary network at a minimum feedback cost for the secondary networks.
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Roy, Prateep Kumar. "Analysis & design of control for distributed embedded systems under communication constraints." Phd thesis, Université Paris-Est, 2009. http://tel.archives-ouvertes.fr/tel-00534012.
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Les Systèmes de Contrôle Embarqués Distribués (SCED) utilisent les réseaux de communication dans les boucles de rétroaction. Étant donné que les systèmes SCED ont une puissance de batterie, une bande passante de communication et une puissance de calcul limitée, les débits des données ou des informations transmises sont bornées et ils peuvent affecter leur stabilité. Ceci nous amène à élargir le spectre de notre étude et y intégrer une étude sur la relation entre la théorie du contrôle d'un coté et celle de l'information de l'autre. La contrainte de débit de données induit la quantification des signaux tandis que les aspects de calcul temps réel et de communication induit des événements asynchrones qui ne sont plus réguliers ou périodiques. Ces deux phénomènes donnent au SCED une double nature, continue et discrète, et en font des cas d'étude spécifiques. Dans cette thèse, nous analysons la stabilité et la performance de SCED du point de vue de la théorie de l'information et du contrôle. Pour les systèmes linéaires, nous montrons l'importance du compromis entre la quantité d'information communiquée et les objectifs de contrôle, telles que la stabilité, la contrôlabilité/observabilité et les performances. Une approche de conception conjointe de contrôle et de communication (en termes de débit d'information au sens de Shannon) des SCED est étudiée. Les principaux résultats de ces travaux sont les suivants : nous avons prouvé que la réduction d'entropie (ce qui correspond à la réduction d'incertitude) dépend du Grammien de contrôlabilité. Cette réduction est également liée à l'information mutuelle de Shannon. Nous avons démontré que le Grammien de contrôlabilité constitue une métrique de l'entropie théorique de l'information en ce qui concerne les bruits induits par la quantification. La réduction de l'influence de ces bruits est équivalente à la réduction de la norme du Grammien de contrôlabilité. Nous avons établi une nouvelle relation entre la matrice d'information de Fisher (FIM) et le Grammien de Contrôlabilité (CG) basé sur la théorie de l'estimation et la théorie de l'information. Nous proposons un algorithme qui distribue de manière optimale les capacités de communication du réseau entre un nombre "n" d'actionneurs et/ou systèmes concurrents se basant sur la réduction de la norme du Grammien de Contrôlabilité
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Torstensson, Maja, and Elin Vinblad. "Intervention med responsiva talakter inom AKK hos två deltagare med cerebral pares i Tanzania : en single subject design-studie." Thesis, Linköpings universitet, Institutionen för klinisk och experimentell medicin, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78991.
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I många utvecklingsländer finns en begränsad tillgång på utvecklade AKK-system (Alant, 1999) och ofta även en okunskap kring möjligheterna att arbeta med kommunikationsproblem (Marshall, 1997). I föreliggande studie genomförs intervention i alternativ och kompletterande kommunikation (AKK) för två deltagare med cerebral pares på ett dagcenter i Kilimanjaroregionen, Tanzania. Syftet i föreliggande interventionsstudie är att genom intervention studera och utveckla de i mätsituationerna responsiva talakterna att påkalla uppmärksamhet för att inleda interaktion, acceptera och avfärda samt upprätthålla och avsluta interaktion. Detta sker med hjälp av begreppen ja och nej för att acceptera och avfärda, liksom mer och mindre för att upprätthålla och avsluta interaktion. Studien följer en single subjekt design och insatsen utgörs av två interventionsperioder, bestående av direkt intervention med deltagarna samt utbildning och fortlöpande handledning av personal. Resultaten visar att deltagarna i varierande grad lärde sig att påkalla uppmärksamhet för att inleda interaktion, acceptera och avfärda samt upprätthålla och avsluta interaktion. Det observerades även att deltagarna i högre grad utförde performativa talakter utanför den styrda testsituationen. Områden som vidare diskuteras är bland annat deltagarnas kommunikativa handlingar utifrån The Communication Matrix där en utveckling från prelingvistiska uttrycksätt till användandet av abstrakta symboler synliggjordes hos deltagarna.<br>In several developing countries there are a limited supply of developed AAC systems (Alant, 1999) whereas a lack of knowledge about the possibilities of working with communication problems (Marshall, 1997). The present study is an intervention study about the introduction of augmentative and alternative communication (AAC) for two participants with cerebral palsy at a day-care centre in the Kilimanjaro Region, Tanzania. The purpose of the intervention study was to develop responsive speech acts to attract attention to initiate interaction, accept and reject interaction, as well as maintain and terminate interaction. This was done using the terms yes and no to accept and reject, and more and less to continue and terminate interaction. The study followed a single subject design consisting of two intervention periods, where direct intervention with the participants and continuing training and guidance for the staff occurred. The results show that the participants in varying degrees, has learned to attract attention to initiate interaction, accept and reject interaction as well as to maintain and terminate interaction. It was also observed that the participants learned to use the performative speech acts outside the controlled test situation. An area further discussed is the participants’ communicative acts as shown in The Communication Matrix, which displayed a development from pre linguistic models of expression to use the abstract symbols.
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Gabison, Éric. "Métalloproteinases matricielles et cicatrisation cornéenne : rôle D'EMMPRIN et des interactions epithélio-stromales." Paris 7, 2008. http://www.theses.fr/2008PA077233.
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Au cours de la cicatrisation cornéenne pathologique, l'activité des métalloprotéinases matricielles (MMPs) normalement bien régulée est altérée. La première partie de ce travail a été consacrée à l'étude des MMPs au cours des ulcérations de cornée. Nous avons montré leur augmentation dans la zone sous épithéliale des berges d'ulcères ce qui suggère l'implication d'interactions épithélio-stromales dans cette induction. Les enzymes induites et leur localisation à l'interface de deux types cellulaires évoquent les mécanismes observés au cours de la progression tumorale ou EMMPRIN, glycoprotéine exprimé à la surface des cellules tumorales, favoriserait la synthèse des MMPs par les fibroblastes directement à leur contact. Nous avons démontré l'expression d'EMMPRIN au niveau de la cornée saine et étudié son implication dans la pathogénie des ulcérations cornéennes. In vivo, EMMPRIN est préférentiellement exprimé au niveau de l'épithélium et de l'endothélium cornéen, plus faiblement à la surface des fibroblastes et son expression augmente fortement dans la zone ulcérée parallèlement à celle des MMPs. Nous avons montré que cette augmentation pouvait être du à sa régulation par des cytokines, ou du fait du contact direct avec des cellules épithéliales. Nous avons ensuite démontré que le contact direct de cellules épithéliales avec des cellules stromales était à l'origine d'une induction de MMPs via EMMPRIN. Nous avons défini ce nouveau mécanisme d'induction des MlVÏPs au cours de la cicatrisation : « interaction épithélio-stromale directe » qui s'ajoute aux interactions épithélio-stromales médiées par les cytokines dans la physiopathologie de la cicatrisation cornéenne<br>Matrix metalloproteinase (MMP) activity, usually well controlled, is unrepressed during the pathological corneal healing. In the first part of this work we studied MMPs production during corneal ulcerations. We showed their over-expression in the stroma underlying the healing epithelium, suggesting a localized induction mediated by epithelial-stromal interactions. The enzymes induced and their localization in the interface of two cell types are reminiscent to what is observed during tumor progression where EMMPRIN, glycoprotein expressed on tumor cell surface, promotes MMP synthesis by fibroblasts directly in contact with tumor cells. The second part of this work constitutes the study of EMMPRIN expression in vivo during corneal ulcerations and in corneal cells in culture. In vivo, EMMPRIN is preferentially expressed in the corneal epithelium,. Endothelium and more slightly on the fibroblast cell surface. Its expression increases in the ulcerated stroma in parallel to MMP activity. In vitro, cytokines and cell-cell interactions modulate EMMPRIN production. The epithelial cells and fibroblasts co-culture stimulates EMMPRIN and MMP-2 synthesis in the fibroblasts directly in contact with epithelial cells. Additionally, purified epithelial cell membranes stimulate via EMMPRIN the production of MMPs by corneal fibroblasts in culture. We therefore showed the implication of EMMPRIT^ in the induction of MMPs via cell-cell contact and coined "direct epithelial-stromal interactions" this proposed new mechanism of MMP stimulation during wound healing
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Stokes, Allison. "A study in the relationships between organizational structures and public relations practitioner roles." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001364.
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Acri, Giuseppe. "Sensibilité à la technologie et accordabilité des matrices de Butler en guide intégré dans le substrat, déclinées sur substrat PCB à 28 GHz et sur interposer above-IC benzocyclobutène aux fréquences millimétriques." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT019.
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Les technologies réseau sont devenues de plus en plus omniprésentes au cours des deux der-nières décennies. En particulier, la 5G (cinquième génération) devrait supporter des vitesses haut débit nettement plus rapides, des capacités de transfert cent fois plus élevées et des re-tards plus faibles que la générations 4G précédente tout ceci permettant d’utiliser le plein potentiel de l’Internet des Objets. Plus précisément, le spectre sous-employé des bandes de fréquences millimétriques (mm-wave) (30-300 GHz) pourrait être considéré comme une solution potentiellement rentable pour atteindre les objectifs susmentionnés. Dans un tel contexte, les systèmes d’antennes à faisceau commuté sont devenus d’un grand intérêt parce qu’ils peuvent atteindre une plus grande efficacité spectrale et améliorer le bilan de puis-sance des systèmes de communication sans fil. Plus spécifiquement, la matrice de Butler (BM) est l’un des réseaux de formation de faisceaux multiples les plus intéressants, intensi-vement exploré et largement employé dans les systèmes de communication en raison de ses propriétés conjointes d’adaptation, d’isolation, et d’équipartition de puissance.Le travail réalisé dans le cadre de cette thèse de doctorat se concentre sur la conception de matrices de Butler en topologie SIW pour les applications millimétriques. Plusieurs bandes de fréquence ont été abordées à cette fin. La bande autour de 28 GHz intéresse particulière-ment la 5G. Ainsi, le concept de matrice étendue en technologie PCB-SIW est introduit pour la BM 4x4, permettant d’atteindre une meilleure résolution spatiale que le simple système 4x4. La bande WR10 (75 GHz-110 GHz) ainsi que quelques bandes millimétriques au-delà ont également été étudiées. Pour ces dernières, le recours à des substrats intermédiaires dé-diés au millimétrique, appelées interposeurs, s’est révélé indispensable. Dans les deux cas, les structures proposées ont été détaillées, des analyses théoriques élaborées et les résultats de simulation confortés par la mesure, accompagnés de rétro-simulations si besoin, dans le but de proposer des preuves de concept. L’un des principaux objectifs de ce manuscrit est d’améliorer la couverture spatiale de l’antenne et la performance du système de formation du faisceau par rapport à son homologue conventionnel tout en gardant presque inchangé la surface du réseau (coûts réduits et complexité de conception). Un autre objectif est d’étudier la sensibilité du système afin de révéler les points faibles de la matrice de Butler.Le premier chapitre de cette thèse présente un état de l’art des dites matrices, RF et mm-wave , et détaille les solutions permettant d’étendre l’orientation du faisceau. Dans le deu-xième chapitre, l’attention se concentre sur une étude Monte Carlo de sensibilité de la BM quasiment exhaustive. Dans le troisième chapitre, les avantages et inconvénients du chan-gement continu et/ou digital de phase sont discutés et un déphaseur SIW 1-bit, 28-GHz, uti-lisant des diodes PIN, est conçu et testé. Ce déphaseur est un des blocs phare de la matrice de Butler étendue. Le quatrième chapitre présente la conception et la mesure des blocs de la BM à 28 GHz ainsi que l’ensemble des mesures du système complet étendu. Dans le cin-quième chapitre, des guides, coupleurs et crossovers SIW sur interposeur BCB (benzocyclo-butene), tous blocs de la matrice, ont été conçus et mesurés en bande WR10 et WR5. Ils con-firment les performance très intéressante du BCB. En perspective, le concept de matrice de Butler étendue pourrait être mis en œuvre sur interposeur BCB mais aussi dans d’autres technologies telles que les membranes à nanofils métalliques (MnM) pour des applications sous-THz<br>Networking technologies have become increasingly omnipresent over the past two decades. In particular, 5G (fifth generation) is expected to support significantly faster mobile broad-band speeds, lower latencies and hundreds of times more capacity than current 4G (fourth generation) while also enabling the full potential of the Internet of Things. Specifically, the underemployed spectrum in the millimeter-wave (mm-wave) frequency bands (30-300 GHz) might be seen as a potentially profitable solution for achieving the aforementioned goals. In such a context, the switched-beam antenna (SBA) systems have become of great interest because they can achieve high spectral efficiency and increase the capacity of wireless communication systems. More specifically, Butler matrix (BM) is one of the most important multiple beam forming networks, which has been intensively explored and extensively em-ployed in communication systems due to its unique properties as perfect matching, isolation, and equal power division, that can be obtained at the same time.The work achieved in this PhD thesis was focused on the conception of a Butler matrix, for mm-wave applications in SIW topology. Two frequency bands were mainly addressed for that purpose. The first one is the band around 28 GHz, that is suited for 5G, where an ex-tended beam agility concept was introduced for 4ⅹ4 Butler matrix, in PCB-SIW technology, to achieve a better spatial resolution, as compared to a 4ⅹ4 conventional system. The second one is the WR10 band (75 GHz-110 GHz), as well as some extra-bands beyond, for which the use of intermediate packaging platforms, so-called interposers, allow the frequency ris-ing as compared to the conventional PCB technologies. In both, the proposed structures were detailed, theoretical analyses were developed, and simulation and measurement works were carried out, with retro-simulations when needed, which permitted to validate the proposed concepts. One of the main goals of this manuscript is to enhance the spatial antenna cover-age and the performance of the beam forming system as compared to its conventional coun-terpart while keeping almost unchanged the surface (reduced costs and design complexity). Another goal is to study the sensitivity of the system, so that the weak points of the BM are revealed.In the first chapter of this thesis, BM solutions for RF and mm-Wave circuits were present-ed, and beam-steering enhanced ability BMs was detailed. In the second chapter, attention focuses on a detailed sensitivity BM study based on a Monte Carlo approach and a proposed solution for extended beam Butler matrices well suited to SIW technology. In the third chap-ter, the pros and cons of continuous and digital phase shifting are discussed and a 28-GHz ,1-bit, SIW, phase shifter using PIN diodes, is designed and tested as a solution to be used in the extended beam matrix. In the fourth chapter, the design blocks for 28 GHz SIW Butler matrix were introduced and measured, along with the entire BM measurements. In the fifth chapter, benzocyclobutene (BCB) SIW useful for Butler matrix blocks were designed and measured in WR10 and WR5 bands, which show the very interesting performance of such an interposer. Even coupler and crossover were fabricated and measured in WR10 band. As a prospect, the extended beam agility BM concept could be implemented in BCB interposer or other kind of interposers as metallic nanowire membranes (MnM) for sub-THz applications, to test the feasibility
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Paturel, Vivien. "QS-13 : développement d’un peptide visant l’angiogenèse tumorale dans le cancer colorectal et étude la communication intercellulaire via les vésicules extracellulaires." Electronic Thesis or Diss., Reims, 2024. http://www.theses.fr/2024REIMS040.
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Avec 47582 nouveaux cas en 2023, le cancer colorectal (CRC) constitue la deuxième cause de décès par cancer en France avec près de 12 % de l’ensemble des décès, en particulier chez les plus de 65 ans. Le taux de survie à 5 ans est estimé à 63 %. Le cancer du côlon provient, dans plus de 80 % des cas, d’une tumeur bénigne appelée polype adénomateux qui évolue lentement en tumeur maligne. Les thérapies actuelles comportent de nombreux effets secondaires. De plus, tous les patients n’y répondent pas et elles peuvent induire des phénomènes de résistance. La recherche de nouvelles stratégies thérapeutiques visant à limiter la progression du CRC demeure donc un défi majeur. Le domaine non collagénique NC1 de la chaîne α4 du collagène de type IV, une séquence de 230 acides aminés aussi nommée Tétrastatine, a montré des propriétés inhibitrices sur la progression du mélanome. Le peptide QS-13, identifié comme la séquence minimale active de la Tétrastatine, reproduit ses effets anti-tumoraux et possède une activité anti-angiogénique, médiée par son interaction avec les intégrines αvβ3 et α5β1. Ce peptide comporte 13 acides aminés (QKISRCQVCVKYS) et présente un pont disulfure entre les résidus cystéine qui se forme spontanément en solution. Cependant, le peptide QS-13 présente une solubilité limitée en milieu aqueux, nécessitant une dissolution préalable dans le DMSO, ce qui constitue un frein pour une utilisation thérapeutique. En utilisant des outils bio-informatiques, nous avons démontré que le DMSO pouvait faciliter la formation des ponts disulfures, mais qu'il n'était pas strictement nécessaire. Des substitutions d'acides aminés hydrophobes ont été réalisées pour améliorer la solubilité du peptide QS-13. L’interaction des différents peptides obtenus avec les intégrines αvβ3 et α5β1 a été analysée in silico en utilisant des approches de docking moléculaire. Il a été démontré que tous ces peptides pouvaient se lier aux intégrines à proximité du site de liaison pour RGD, leur permettant potentiellement de concurrencer des ligands tels que la fibronectine, ainsi que FGF1, FGF2, IGF1 et IGF2, et de modifier la signalisation des voies FAK/PI3K/Akt. Parmi les différents peptides étudiés, nous avons sélectionné le peptide QS-13-3, peptide présentant l'indice de stabilité le plus élevé et un indice d'hydropathie élevé avec seulement 2 acides aminés substitués. Les résultats obtenus in vitro sur des cellules de mélanome ont confirmé que les substitutions réalisées n'altéraient pas l'efficacité biologique originelle. Par ailleurs, les domaines NC1 du collagène IV ont été décrits comme présentant des analogies de structure avec le TIMP-2, un inhibiteur tissulaire de métalloprotéinases matricielles (MMPs), enzymes qui jouent des rôles critiques dans la progression tumorale en dégradant les composants de la matrice extracellulaire et en facilitant l'invasion et la formation de métastase des cellules cancéreuses, ainsi que l’angiogenèse. Nous nous sommes donc intéressés aux interactions potentielles des peptides QS-13 et QS-13-3 avec ces MMPs. À l'aide d'outils bio-informatiques (in silico), nous avons montré qu’ils pouvaient se fixer de manière directe aux MMP-2 et MMP-14, puis nous avons mis en évidence une inhibition dose-dépendant de l’activité catalytique de ces deux MMPs. Enfin, les premiers résultats obtenus sur les effets des peptides QS-13 et QS-13-3 sur la communication intercellulaire via les vésicules extracellulaires ainsi que les effets observés dans différents modèles in vitro, ex vivo et in vivo ont permis de confirmer l'efficacité thérapeutique potentielle des peptides QS-13 et QS-13-3 dans la lutte contre la progression du CRC et l’angiogenèse tumorale<br>With 47582 new cases in 2023, colorectal cancer (CRC) is the second most common cause of cancer-related death in France, accounting for almost 12% of all deaths, particularly in people over 65. The 5-year survival rate is estimated at 63%. In over 80% of cases, colon cancer stems from a benign tumour called an adenomatous polyp, which slowly evolves into a malignant tumour. Current therapies have numerous side effects. Moreover, not all patients respond to them, and they can induce resistance phenomena. The search for new therapeutic strategies to limit CRC progression therefore remains a major challenge. The non-collagenous NC1 domain of the α4 chain of type IV collagen, a 230 amino acid sequence also known as Tetrastatin, has been shown to inhibit melanoma progression. The QS-13 peptide, identified as the minimal active sequence of Tetrastatin, mimics its anti-tumor effects and possesses anti-angiogenic activity, mediated by its interaction with αvβ3 and α5β1 integrins. This peptide comprises 13 amino acids (QKISRCQVCVKYS) and features a disulfide bridge between cysteine residues that spontaneously forms in solution. However, the QS-13 peptide has limited solubility in aqueous media, requiring prior dissolution in DMSO, which is an impediment to its therapeutic use. Using bioinformatics tools, we demonstrated that DMSO could facilitate disulfide bridge formation but was not strictly necessary. Hydrophobic amino acid substitutions were made to improve the solubility of the QS-13 peptide. The interaction of the new designed peptides with αvβ3 and α5β1 integrins was analyzed in silico using molecular docking approaches. All these peptides were able to fix integrins close to the RGD binding site, potentially enabling them to compete with ligands such as fibronectin, as well as FGF1, FGF2, IGF1 and IGF2, and to modify FAK/PI3K/Akt signaling pathway. Among the peptides studied, we selected QS-13-3, the peptide with the highest stability index, a high hydropathy index and only 2 substituted amino acids. The results confirmed that the substitutions did not alter peptide biological efficacy. It was reported that NC1 domains of collagen IV show structural analogies with TIMP-2, a tissue inhibitor of matrix metalloproteinases (MMPs). We therefore focused on the potential interactions of QS-13 and QS-13-3 peptides with these MMPs. Using bioinformatics tools (in silico), we showed that they could bind directly to MMP-2 and MMP-14, and then demonstrated a dose-dependent inhibition of the catalytic activity of both MMPs. Finally, the results obtained on the effects of QS-13 and QS-13-3 peptides on intercellular communication via extracellular vesicles, as well as the effects observed in various in vitro, ex vivo and in in vivo models, confirmed the potential therapeutic efficacy of QS-13 and QS-13-3 peptides in limiting CRC progression and tumor angiogenesis
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Calvin, Christophe. "Minimisation du sur-coût des communications dans la parallélisation des algorithmes numériques." Phd thesis, Grenoble INPG, 1995. http://tel.archives-ouvertes.fr/tel-00005034.
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Le but de ce memoire est d'étudier les voies possibles pour minimiser le sur-coût des communications consécutif à la parallélisation d'algorithmes numériques sur machines parallèles à mémoire distribuée. La première voie explorée consiste à optimiser les schémas de communication des données et résultats mis en oeuvre dans les versions parallèles de noyaux de calcul. Nous proposons notamment de nouveaux algorithmes pour réaliser une transposition de matrices carrées allouées par blocs, sur différentes topologies de réseaux d'interconnexion. Nous avons également étudié le problème de l'échange total. Ce schéma de communication se retrouve fréquemment dans les versions parallèles d'algorithmes numériques (comme dans l'algorithme du gradient conjugué). Nous proposons des algorithmes efficaces d'échange total pour des topologies toriques. La deuxième voie qui a été explorée consiste à recouvrir les communications par du calcul. Nous avons étudié quelques principes algorithmiques de base permettant de masquer au mieux les communications. Ceux-ci sont basés, notamment, sur des techniques d'enchainement de phases de calcul et de communication, ainsi que sur le re-ordonnancement local de tâches afin d'optimiser le recouvrement. Ces techniques sont illustrées sur des algorithmes parallèles de calcul de transformée de Fourier. Les différentes implantations de ces algorithmes sur de nombreuses machines parallèles à mémoire distribuée (T3D de Cray, SP2 d'IBM, iPSC-860 et Paragon d'Intel) montrent le gain en temps d'exécution apporté par ces méthodes.
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Oubaha, Khalid. "Transport micro-ondes dans un milieu complexe vers une communication sans fil à base des circuits intégrés." Thesis, Université Côte d'Azur, 2020. http://www.theses.fr/2020COAZ4061.
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De nos jours, nous assistons à une forte évolution des systèmes modernes de la communication sans fil, exploitant des fréquences très élevées, dans la bande des fréquences micro-ondes. De ce fait, pour éviter des architectures compactes des systèmes électroniques composant ces systèmes modernes, apparaît la nécessité d'envisager la communication sans fil entre les circuits imprimés intégrés aux systèmes électroniques.Les principaux problèmes rencontrés dans ces systèmes concernent l'effet de l'environnement sur la communication sans fil et la protection contre les effets indésirables. Cela exige de nouvelles techniques de simulation et de modélisation du champ EM dans ces environnements complexes, pour une prédiction de leurs comportements.Avec les expériences effectuées dans le domaine des micro-ondes, ces techniques seront possibles en se basant sur la théorie des matrices aléatoires (TMA), bien adaptée dans ces situations de milieu complexe.Les travaux effectués au cours de cette thèse présentent :Dans un premier temps, l'illustration d'un exemple d'une telle situation où tous les ingrédients sont présents (circuit imprimé, lignes de transmissions et cavité). Nous avons présenté une étude expérimentale, qui met en évidence l'effet de l'environnement partiellement réverbérant sur la diaphonie entre les lignes imprimées, de sorte que leurs courants ne soient pas négligés et doivent être pris en compte, pour la conception appropriée de circuit imprimé, garantissant leur fonctionnement.Dans un second temps, dans le but d'étudier et d'analyser statistiquement le comportement de la transmission à l'intérieur d'un milieu complexe, nous avons réalisé une chambre réverbérante chaotique (CRC), qui satisfait aux critères statistiques fixés par la norme internationale. Le critère principal exige d'avoir une uniformité et isotropie statistique du champ à l'intérieur de la CRC et que les composantes du champ suivent une distribution gaussienne bivariée. Dans la communauté de la Compatibilité d'Électromagnétique (CEM), on parle de l'hypothèse de Hill, typiquement réalisée quand le recouvrement modal est grand. Nous avons étudié expérimentalement plusieurs statistiques de la réponse de la CRC et les effets du régime de fort recouvrement modal sur les distributions de la réflexion et la transmission, puis nous les avons comparées aux prédictions numériques prévues par la TMA.Nous avons également vérifié la relation de l'espacement moyen entre les maxima de transmission prédite par Schroeder et Kuttruff pour un régime fort recouvrement modal, dans les salles acoustiques.Dans un troisième temps, nous avons développé une nouvelle méthode pour l'estimation de nombre d'échantillons non corrélés (NIS) dans une CRC. Puis nous avons suggéré une perspective pour l'estimation de NIS, basée sur l'échelle caractéristique de la dynamique des maxima en fonction de l'angle de brasseur<br>Nowadays, modern wireless communication systems that are operating at high frequencies in the microwave band, are massively emerging. To avoid compact architectures of electronic systems, we explore wireless communication between printed circuits integrated into the electronic systems. Several problems encountered in these systems are related to the effect of the environment on wireless communication and the protection against adverse effects. This requires new electromagnetic simulation techniques to describe the field and the system response in these environments. Along with the microwave experiments, random matrix theory (RMT) enables to theoretically study wireless communication in complex environment.This manuscrit is diveded in three main topics:On the one hand, an illustration of the situation where all the ingredients are implemented namely, a Printed Circuit Board (PCB) with transmission lines inside a cavity. I present an experimental study, which highlights the effect of the partially reverberating environment on the crosstalk of two printed lines, as well as the currents on these lines. The latter should be taken into account to guarantee the proper functioning of the PCB.On the other hand, a chaotic reverberating chamber (CRC) was designed to statistically analyze the behavior of the transmission inside a complex environment. The international standard fix several statistical criteria with which the RC have to comply. Fulfilling all criteria guarantees that the field inside the cavity is isotropic and the field components follow a bivariate Gaussian distribution. In the electromagnetic community, this is the so-called Hill’s hypothesis. This hypothesis is typically realized when the resonance overlap is large. I have experimentally studied several statistic properties of the electromagnetic response in a CRC. The effects of the modal overlap on the reflection and the transmission distributions have been analyzed. In addition to this, we have compared the experimental distributions to numerical predictions based on Random Matrix Theory. I also verified the relation between the mean frequency spacing of the maxima and the average decay rate of the cavity predicted by Schroeder and Kuttruff for a high modal overlap in acoustic rooms.Finaly, we have developed a new method to estimate the number of uncorrelated samples (NIS) in a CRC. We have suggested a perspective for NIS estimation based on the characteristic scale of maxima dynamics as a function of the stirrer angle
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Malík, Martin. "Marketingový plán vybrané společnosti." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-200166.
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The aim of this diploma work is an elaboration of a marketing plan of TEDOM Company. Then the analysis of marketing tools and creation of a new marketing communication and setting the budget for its implementation. The theoretical part of the work is focused on the characteristics of marketing plan and marketing communication. The practical part describes the company itself. Furthermore the marketing plan and marketing communications are developed.
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Alvén, Annica. "Idrottsmän och idrottskvinnor : Slaktar rekord och får folkets kärlek på kvällstidningarnas sportsidor." Thesis, Uppsala University, Media and Communication, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9145.
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<p>Purpose/Aim: The aim of this thesis was to study the construction of gender and to compare Media’s portrayal of male and female athletes.</p><p>Material/Method: 140 articles covering seven famous Swedish male and female athletes were selected from two Swedish newspapers (Aftonbladet and Expressen). The articles has been analysed within the frames of Norman Faircloughs Critical Discourse Analysis.</p><p>Main results: Male athletes are often described in powerful ways and are framed as being strong and successful. Skills and strengths of women athletes are often devalued in comparison to standards of hegemonic masculinity and self-control. They are often framed as women and girlfriends in advantage of the fact that they are athletes.</p>
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Hamieh, Hamzeh. "Caractérisation diélectrique de parois de bâtiments : conception d'un banc de msure impulsionnel Ultra Large Bande (ULB) et détermination des paramètres pertinents de diverses parois." Limoges, 2012. http://aurore.unilim.fr/theses/nxfile/default/ca0fe54a-b230-4f56-b08a-0e2b1735a50a/blobholder:0/2012LIMO4051.pdf.
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Ce mémoire présente la mise en œuvre d'un banc de mesure in-situ en espace libre, ULB transitoire, associé à des techniques d'extraction des propriétés diélectriques dans le but de caractériser les parois de bâtiments. Les techniques de mesures développées au sein de l'équipe OSA d'XLIM sont appliquées et adaptées à la mesure de la réflexion et de la transmission à travers les parois. Associées à des techniques d'extraction élaborés durant l'étude, les propriétés des matériaux sont déduites. Les moyens mis en œuvre pour caractériser les matériaux sont présentés et validés via des simulations électromagnétiques rigoureuses. Deux matériaux font enfin l'objet de caractérisation expérimentales : la pierre et le parpaing<br>This thesis presents the implementation of a measurement bench, in free space, UWB transient, associated with extraction techniques of dielectric properties in order to characterize the walls of buildings. The measurement techniques developed within the team of OSA XLIM are applied, adapted and improved for measuring the reflection and transmission through the walls. Associated with extraction techniques developed during the study, the material properties are obtained. The means used to characterize the material are presented and validated through rigorous electromagnetic simulations. Finally, two materials are subject to experimental characterization : the natural rock and the concrete blocks
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Langer, Markus E., Aloisia Schön, Michaela Egger-Steiner, and Irmgard Hubauer. "Implementing evaluation in the context of sustainable development (II). The strategic orientation in the context of evaluations with sustainable development as part of a Tool Box." Forschungsschwerpunkt Nachhaltigkeit und Umweltmanagement, WU Vienna University of Economics and Business, 2003. http://epub.wu.ac.at/104/1/document.pdf.
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In the context of sustainable development, evaluations have particularly high relevance as complex issues have to be dealt with generally over an extended period of time. Furthermore, there is a growing demand to evaluate against the concept of sustainable development. Especially evaluations with sustainable development are a rather new type of evaluation, as the source of its evaluation questions and the criteria applied are rooted in the concept of sustainable development. Sustainability of a specific project or process is often highly case specific as sustainable development is determined by many often unique issues. However, evaluations would be highly inefficient, if they would have to be newly designed in every case. Thus it is necessary to determine and utilize the major issues for evaluations with sustainable development. This paper is part of a series of three papers - which can be used independently - that present the major common issues for evaluations with sustainable development in a Tool Box. The results presented here are based on outcomes of a research project funded by the "Austrian Science Fund". This paper includes the "strategic orientation tool", which was developed as a tool for reflection and decision upon the general outline of an evaluation with sustainable development. It helps to define a design- frame with respect to its information-focus, scope and utilization. The core of the tool is a matrix that is based on two key- functions. On the one hand it defines which contents should be assessed: "What is the object of evaluation?". On the other hand it is oriented along the actual utilization of the evaluation: "How the gained results of the evaluation should be communicated and to whom?". (author's abstract)<br>Series: Research Paper Series of the Research Focus Managing Sustainability
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Hrabčík, Oldřich. "Modely distribuční sítě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218883.
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This thesis deals with transmission of data over power-line. There is theoretically described PLC technology and its classification, properties and used modulation techniques. A substantial part is focused on the mathematical description of distribution network using two methods, with multipath propagation and ABCD matrix. These methods are mutually compared. Furthermore, they are examined depending on the transfer functions of the topology and capabilities for unknown topology. Calculations of transfer functions are implemented using Matlab. The results were then processed graphically and evaluated.
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Hiltunen, Sonja. "Systèmes MIMO pour formes d'ondes mono-porteuses et canal sélectif en présence d'interférences." Thesis, Paris Est, 2015. http://www.theses.fr/2015PESC1206/document.
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La synchronisation temporelle des systèmes MIMO a été abondamment étudiée dans les quinze dernières années, mais la plupart des techniques existantes supposent que le bruit est blanc temporellement et spatialement, ce qui ne permet pas de modéliser la présence d'interférence. Nous considérons donc le cas de bruits blancs temporellement mais pas spatialement, dont la matrice de covariance spatiale est inconnue. En formulant le problème de l'estimation de l'instant de synchronisation comme un test d'hypothèses, nous aboutissons au test du rapport de vraisemblance généralisé (GLRT) qui donne lieu à la comparaison avec un seuil d'une statistique de test eta_GLRT. Cependant, pour des raisons de complexité, l'utilisation de cette statistique n'est pas toujours considérée comme réaliste. La première partie de ce travail a donc été consacrée à mettre en évidence des tests alternatifs moins complexes à mettre en œuvre, tout en ayant des performances similaires. Une analyse comparative exhaustive, prenant en considération le bruit et l'interférence, le type de canal, le nombre d'antennes en émission et en réception, et l'orthogonalité de la séquence de synchronisation est réalisée. Enfin, nous étudions le problème de l'optimisation du nombre d'antennes en émission K pour la synchronisation temporelle, montrant que pour un RSB élevé, les performances augmentent avec K dès que le produit de K avec le nombre d'antennes de réception M n'est pas supérieur à 8.Le deuxième aspect de ce travail est une analyse statistique de eta_GLRT dans le cas où la taille de la séquence d'apprentissage N est du même ordre de grandeur que M, ce qui conduit naturellement à étudier le comportement de eta_GLRT dans le régime asymptotique des grands systèmes M tend vers l'infini, N tend l'infini de telle sorte que M/N tende vers une constante non nulle. Nous considérons le cadre applicatif d'un système muni d'une unique antenne d'émission et d'un canal à trajets multiples, qui est formellement identique à celui d'un système MIMO dont le nombre d'antennes d'émissions correspondrait au nombre de trajets. Lorsque le nombre de trajets L est beaucoup plus faible que N et M, nous établissons que eta_GLRT a un comportement gaussien avec l'espérance asymptotique L log (1 / (1-M/N)) et la variance (L/N)*(M/N)/(1-M/N). Ceci est en contraste avec le régime asymptotique standard quand N tend vers l'infini et M et L fixe où eta_GLRT a un comportement chi2. Sous l'hypothèse H_1, eta_GLRT a aussi un comportement gaussien. Nous considérons également le cas où le nombre de trajets L tend vers l'infini à la même vitesse que M et N. Nous utilisons des résultats connus concernant le comportement des statistiques linéaires des valeurs propres des grandes F matrices, et déduisons que dans le régime où L,M,N tendent vers l'infini à la même vitesse, eta_GLRT a encore un comportement gaussien sous H_0, mais avec une espérance et variance différentes. L'analyse de eta_GLRT sous H_1 lorsque L,M,L convergent vers l'infini nécessite l'établissement d'un théorème central limite pour les statistiques linéaires des valeurs propres de matrices F de moyennes non-nulles, une tâche difficile. Motivé par les résultats obtenus dans le cas où L reste fini, nous proposons d'approximer la distribution asymptotique par une distribution gaussienne dont l'espérance et la variance sont la somme de l'espérance et la variance asymptotique sous H_0quand L tend vers l'infini avec l'espérance et la variance asymptotique sous H_1 dans le régime classique N tend vers l'infini et M fixé. Des simulations numériques permettent de comparer les courbes ROC des différents approximant avec des courbes ROC empiriques. Les résultats montrent que nos approximant de grandes dimensions fournissent de meilleurs résultats quand M/N augmente, tout en permettant de capturer la performance réelle pour les petites valeurs de M/N<br>Time synchronization of MIMO systems have been strongly studied in the last fifteen years, but most of the existing techniques assume a spatially and temporally white noise, which does not allow modeling the presence of interference. We consider thus a temporally white but spatially colored noise, with an unknown covariance matrix. Formulating the estimation problem as a hypothesis testing problem, we obtain a Generalized likelihood ratio test (GLRT), which gives us a synchronization statistics eta_GLRT. However, for complexity reasons, it is not always considered realistic for practical situations. A part of this work has thus been devoted to showing that there exist non-GLRT statistics that are less complex to implement than theet a_GLRT, while having similar performance. Furthermore, we perform a comparative parameter analysis, taking into consideration the noise type, channel type, the number of transmit and receive antennas, and the orthogonality of the synchronization sequence. Lastly, the problem of optimization of the number of transmit antennas K for time synchronization has been investigated. showing, for high SNR, increasing performance with K as long as the product KM is not larger than 8, where M is the number of receive antennas. The second aspect of MIMO synchronization studied in thesis is asymptotic analysis of the same GLRT, but for large M. In this context, the synchronization sequence length N is the same order of magnitude as M, and this leads us naturally to the study of the the behavior of eta_GLRT in the asymptotic regime where M,N go towards infinity such that M/N go towards a non-zero constant. We consider the case of a single transmit antenna in a multi-path channel, which formally is equivalent to the MIMO system where the transmit antennas correspond to the number of paths. We address the case When the number of paths L does not scale with M and N, we establish that eta_GLRT has a Gaussian behavior with asymptotic mean L log (1/ (1 - M/N))and variance (L/N)*(M/N)/(1-M/N).This is in contrast with the standard asymptotic regime N goes to infinity and M fixed where eta_GLRT has a chi^2 behaviour. Under hypothesis H_1, eta_GLRT still has a Gaussian behaviour. The corresponding asymptotic mean and variance are obtained as the sum of the asymptotic mean and variance in the standard regime N goes to infinity and M fixed, and L log(1/(1-/M/N))L log (1 / (1-M/N)) and (L/N)*(M/N)/(1-M/N)respectively, i.e. the asymptotic mean and variance under H_0.We also consider the case where the number of paths L converges towards infinity at the same rate as M and N. Using known results of concerning the behaviour of linear statistics of the eigenvalues of large F-matrices, we deduce that in the regime where L,M,N converge to infinity at the same rate, eta_GLRT still has a Gaussian behaviour under H_0, but with a different mean and variance. The analysis of eta_GLRT under H_1 whenL,M,N converge to infinity needs to establish a central limit theorem for linear statistics of the eigenvalues of large non zero-mean F-matrices, a difficult ask. Motivated by the results obtained in the case where L remains finite, we propose to approximate the asymptotic distribution of eta_GLRT by a Gaussian distribution whose mean and variance are the sum of the asymptotic mean and variance under H_0when L goes to infinity with the asymptotic mean and variance under H_1 in the standard regime N goes to infinity and M fixed. Numerical simulations allow to compare the ROC curves obtained with the different approximations with the empirical ROC curves. The results show that the large-system approximations provide better results when M/N increases, while also allowing to capture the actual performance for small values of M/N
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Zhao, Sisi. "Cultural Exchange and Media Evaluations Behind Transnational Business Acquisition Between China and the United States: A Qualitative Study of Dalian Wanda-AMC." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1525273039528152.
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Ostrá, Kateřina. "Návrh marketingové strategie vybrané akciové společnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2012. http://www.nusl.cz/ntk/nusl-223621.
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This diploma thesis deals with proposal and creation of marketing strategy of chosen company operating in the industrial market. The main pillar of efficiency of the marketing tools is the new proposal of marketing strategy which integrates activities of company with marketing activities through company processes. This targeted cooperation maximizes effect of the marketing activities of the company. Created synergy effects have to meet defined marketing and communication objectives.
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Sampaio, Cardoso Leonardo. "Orthogonal Precoder for Dynamic Spectrum Access in Wireless Networks." Thesis, Supélec, 2011. http://www.theses.fr/2011SUPL0018/document.
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Le déferlement mondial des services de télécommunications, impose, aux réseaux qui les supportent, d’augmenter de plus en plus leurs capacités afin de subvenir aux besoins de ses utilisateurs dont le nombre ne cesse de croître. Le spectre radio, ressource de base pour les communications sans fils, ne suit malheureusement pas cette croissance. Même si des marges réutilisables sont disponibles, leur accès est limité par des politiques strictes de gestion du spectre radio-fréquentiel. Pour remédier à cette situation, les organismes régulateurs des télécommunications se dirigent vers un paradigme de gestion plus flexible, en autorisant de nouvelles méthodes basées sur l’accès dynamique au spectre (DSA - dynamic spectrum access) et les radio cognitives (CR - cognitive radio). Dans ce travail doctoral, est proposée une nouvelle technique pour traiter la problématique de la disponibilité du spectre radio-fréquentiel. Appelée multiplexage fréquentiel par sous-espace de Vandermonde (VFDM -Vandermonde-subspace frequency division multiplexing), elle permet à deux technologies d’accès radio (RATs - radio access technologies) de fonctionner côte-a-côte dans un environnement de petites cellules CR. Ceci se fait en partageant la bande radio tout en protégeant des interférences les systèmes pour lesquels le spectre radio avait été originellement réservé. VFDM transmet les données pré-codées dans le noyau du canal interférant entre l’émetteur opportuniste et le récepteur originel en utilisant la sélectivité en fréquence des canaux et duplexage temporel (TDD - time division duplexing). Le travail de cette thèse propose une approche exhaustive du développement de la technologie VFDM, en allant des bases théoriques jusqu’à la démonstration de faisabilité. Ainsi, les bases théoriques proposées ont été en premier lieu analysées. Puis, en partant de ces bases théoriques, VFDM a été graduellement développé vers une chaîne émetteur-récepteur complète. Des résultats significatifs sont apparus à mi-chemin dans la phase de développement, comme par exemple, l’établissement de stratégies de précodage optimales ou la mise en évidence d‘aspects critiques lors de l’implémentation. Sous certaines conditions, VFDM permet aux réseaux secondaires opportunistes d’être utilisés en même temps que le réseau originel, aux seules contraintes de la connaissance des canaux et de l’accroissement de la complexité du système. Au travers des résultats obtenus en simulation, il a été démontré que des taux de transfert de données significatifs peuvent être atteints, et ce, malgré que les capacités de VFDM soient toujours limitées par la taille du sous-espace de Vandermonde du canal interfèrent primaire-secondaire. Finalement, la chaîne émetteur-récepteur développée démontre la faisabilité de cette méthode<br>The global deployment of PCS is pushing for more and more network capacity to accommodate an exponentially growing user base. Radio spectrum, the basic resource in radio communications, unfortunately does not follow this growth. Even though the current spectrum usage leaves margins for re-use, it is limited by the current fixed spectrum management policies. To remediate this issue, spectrum regulators are switching to a flexible management paradigm, leveraging new DSA schemes based on CR. In this PhD work, a novel CR-DSA technology is introduced to address spectrum scarcity problem. Called VFDM, it allows two RAT to operate side-by-side in a small-cell CR setting, sharing the band while protecting the legacy system from interference. VFDM transmits data pre-coded on the null-space of the interfering cross channel (channel from the opportunistic transmitter to the legacy receiver), assuming frequency selectivity and TDD communications. This PhD work proposes a rather exhaustive approach to the development of VFDM: to go from the theoretical basis up to a proof-of-concept development. Initially the theoretical background, basis of the technique itself was introduced and analyzed. Then, VFDM was gradually developed from a pure mathematical concept up to a full transceiver. During this development, several important mid-way results were developed, such as the multi-user strategy for pre-coding and critical implementation aspects. VFDM, under certain constraints, has been shown to allow a secondary opportunistic network to successfully be installed along with a legacy primary one at merely the cost of channel knowledge and added complexity. By means of numerical examples, it has been shown that significative rates can be attained, even though VFDM's performance is constrained by the size of the Vandermonde-subspace of the interfering channel between the secondary transmitter and primary receiver. Finally, a working VFDM transceiver implementation is shown, providing a proof-of-concept of the technique
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Сагер, Людмила Юріївна, Людмила Юрьевна Сагер та Liudmyla Yuriivna Saher. "Організаційно-економічні засади управління внутрішніми комунікаціями на промислових підприємствах". Thesis, Вид-во СумДУ, 2014. http://essuir.sumdu.edu.ua/handle/123456789/37158.
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Дисертація присвячена розвитку організаційно-економічних засад управління внутрішніми комунікаціями на промислових підприємствах. Проаналізовано та узагальнено підходи до визначення структури внутрішніх комунікацій. Уточнено роль та місце внутрішніх комунікацій у системі бізнес-процесів підприємства. Систематизовано можливі проблеми побудови ефективної системи управління внутрішніми комунікаціями підприємства. Запропоновано та обґрунтовано науково-методичний підхід до вибору управлінських рішень на основі діагностики стану внутрішніх комунікаційних процесів промислового підприємства. Удосконалено теоретико-методичний підхід до визначення комунікаційних стратегій. Розроблено і науково обґрунтовано методичний підхід до побудови економіко-математичної моделі оптимізації вибору управлінських рішень. Сформовано засади організаційно-економічного механізму управління внутрішніми комунікаціями промислового підприємства. Надано рекомендації щодо управління внутрішніми комунікаціями на підприємствах.<br>Диссертация посвящена развитию и усовершенствованию организационно-экономических основ управления внутренними коммуникациями на промышленных предприятиях. Обоснована сущность понятия «внутренние коммуникации», под которым предложено понимать процесс обмена информацией между отдельными лицами и/или группами лиц на разных уровнях управления организации с помощью традиционных и новейших инструментов и средств, и которое учитывает особенности организации коммуникационной деятельности предприятий, предусматривает четкое определение участников процесса и регламентацию их взаимодействия, а также позволяет оценивать внутренние коммуникации с позиции бизнес-процессов. Дополнена классификация коммуникаций, которая предусматривает выделение следующих признаков: «по инструментам распространения», «по функциональности», «по типу контрагентов», «по организации связей», «согласно инструментам осуществления». В структуре внутренних коммуникаций предложено выделять четыре подсистемы: организационную, социально-психологическую, технологическую и информационную. Такой подход позволяет полнее раскрыть сущность внутренних коммуникаций, проанализировать различные аспекты, точнее оценить их состояние. Установлено, что для промышленного предприятия внутренние коммуникации выступают не только средством обеспечения гибкости и адаптивности предприятия, инструментом развития кадрового и инновационного потенциала, а также формирования организационной культуры на основе целостности целей и ценностей, но и инструментом повышения эффективности бизнес-процессов. С целью формирования эффективной системы мероприятий и средств предотвращения или нивелирования негативных последствий проанализированы и систематизированы основные проблемы, с которыми сталкиваются предприятия при управлении внутренними коммуникационными процессами. Среди них следует выделять проблемы технологического, информационного, социально-психологического и организационного характера. Сформирована классификация показателей диагностики состояния внутренних коммуникаций предприятия согласно выделенным составляющим системы внутренних коммуникаций и их элементам, которая позволяет учитывать все их направления и на этой основе осуществлять максимально обоснованное оценивание. Усовершенствован научно-методический подход к диагностике состояния внутренних коммуникационных процессов, который заключается в расчете интегрального показателя, учитывающего социальную, организационную, технологическую и информационную составляющие системы коммуникаций промышленного предприятия, и позволяет на этой основе осуществлять организацию бизнес-процессов промышленного предприятия. Разработан и научно обоснован теоретико-методический подход к определению коммуникационных стратегий в зависимости от состояния социально-организационной и технико-информационной составляющих внутренних коммуникаций, основанный на определении зон уровня внутренних коммуникационных процессов промышленного предприятия, и позволяющий сформировать комплексную коммуникационную стратегию и определить стратегические направления развития коммуникационного менеджмента предприятия. Для выбора эффективных управленческих действий разработан и научно обоснован методический подход к построению экономико-математической модели оптимизации выбора управленческих решений в рамках выбранной коммуникационной стратегии с учетом минимально допустимого уровня затрат и минимального количества дублирующих функций, обеспечивающих эффективную реализацию бизнес-процесса. Предложен и обоснован научно-методический подход к выбору управленческих решений на основе диагностики состояния внутренних коммуникационных процессов промышленного предприятия. Сформированы основные аспекты организационно-экономического механизма управления внутренними коммуникациями предприятия, который содержит разработку принципов, целей и задач управления внутренними коммуникациями. Исследованы практические аспекты и определены направления совершенствования организационно-экономических засад управления внутренними коммуникациями промышленных предприятий. Основные результаты диссертационной работы прошли практическую апробацию и внедрены на промышленных предприятиях Сумской и Киевской области машиностроительной и химической отраслей.<br>The thesis is devoted to the development of organizational and economic provisions manage internal communications in the industry. It was analyzed and generalized approach to determine the structure of internal communications; specified the role and position of internal communications system in enterprise business processes; proposed and substantiated scientific and methodical approach to the selection of management decisions on the basis of diagnosis internal communication processes of industrial enterprises. Systematized the problem of constructing an effective internal communications system. The author developed and scientifically substantiated methodological approach to the construction of economic and mathematical optimization model of choice-making. It was formed principles of organizational and economic mechanism of internal communications for industrial businesses. Recommendations according internal communications management are given on the enterprises.
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Andersson, Gabriella, and Johanna Dingfors. "Vägen till framtidens hållbara konsument : En kvalitativ studie om hur generation z uppfattar hållbarhetskommunikation i den svenska modebranschen." Thesis, Södertörns högskola, Institutionen för samhällsvetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-45906.
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With the increased focus on climate change, sustainability has become a common term for both organizations as well as consumers. The clothing industry is one of the industries that have the biggest negative impact on climate change. Still, the fast fashion business, based on cheap materials and low production costs, continues to thrive. The clothing companies stand before an increased review from society and are therefore forced to work with sustainability and acceptance. Depending on how the companies handle their communication with regards to sustainability, their consumers are put at risk of being subjectable to greenwashing, since the companies regard themselves to be more sustainable than they are. Generation Z consists of people born between the years of 1995 to 2005 and they were born into the so-called climate crisis. Generation Z is ultimately the generation that will live during the unpredictable future due to climate change. This makes the generation the most environmentally conscious generation yet. Still, the generation is the world’s largest group of consumers, and a large part of their identity lies within how they dress. This study aims to examine how generation Z, as an environmentally conscious group with a lot of purchasing power, perceives the Swedish fashion brand's communication about sustainability. The study is based on a quality method, using focus groups to gather data. This method is chosen since the aim is to analyze generation Z perception, feelings, and ideas. The theory studies terms within the roam of sustainability, both in the Swedish fashion business and as well as marketing. How Swedish fashion companies communicate their work on sustainability and how this is perceived by generation Z is presented via “a linear model of communication”. The result of the study shows that all the respondents have a similar perception of how confidence-inspiring the fashion business combination on sustainability is. Previous research has described generation Z as a consumer group that highly values sustainability, this is in line with the results of this study. The respondents describe that they consume sustainably by shopping second-hand but finds it hard to do sustainable choices when shopping for newly produced clothes. Fashion companies in the fast fashion sector that work with sustainability limited areas of the organization have low to no credibility from the respondents. The will to consume sustainably produced clothes is hindered by the fact that the respondents lack the trust for the actual sustainability in the products and production chain. The respondents seek companies with transparency, since thisincreases their trust and fulfills their will to consume sustainably.<br>I takt med att vår klimatpåverkan ökar har hållbarhet blivit ett uppmärksammat begrepp hos såväl organisationer som hos konsumenter. Modebranschen är en av de branscher som har störst negativ påverkan på miljön, trots detta fortsätter den så kallade fast fashion-industrin, baserad på billiga material och tillverkningskostnader, att blomstra. Modeföretagen står samtidigt inför en ökad granskning av samhället och tvingas att arbeta med hållbarhet för att få acceptans. Beroende på hur företagen väljer att kommunicera sitt hållbarhetsarbete riskerar konsumenterna att bli utsatta för greenwashing, då företagen anser sig vara mer hållbara än vad de egentligen är. Generation z, personer födda mellan åren 1995–2005, är födda in i den så kallade klimatkrisen samt är också den generation som ska leva i en orolig framtid med växande klimatförändringar. Detta resulterar i att målgruppen är den hittills mest kritiska och miljömedvetna av alla generationer. Samtidigt är målgruppen världens största konsumentgrupp och är måna om att skapa sin identitet genom vad de klär sig i. Studien syftar till att undersöka hur generation z som köpkraftig och miljömedveten målgrupp uppfattar de svenska modeföretagens hållbarhetskommunikation. Forskarna har valt en kvalitativ forskningsmetod med fokusgrupper som insamlingsmetod eftersom studien syftar till att på ett djupgående sätt undersöka generation z:s uppfattningar, känslor och idéer. Teorin belyser begrepp som berör området hållbarhet i den svenska modebranschen och hållbar marknadsföring. Hur svenska modeföretag kommunicerar hållbarhetsarbetet och hur detta tolkas av generation z presenteras via kommunikationsmodellen “A linear model of communication”. Resultatet av studien visar att samtliga respondenter har liknande uppfattningar om hur förtroendeingivande modebranschens hållbarhetskommunikation är. Tidigare forskning beskriver generation z som en konsumentgrupp som värderar hållbarhet högt vilket stämmer överens med studiens resultat. Respondenterna beskriver att de handlar mycket hållbart i form av second hand men anser att det är svårt att göra hållbara val av nyproducerade plagg. Modeföretag verksamma inom fast fashion-industrin som arbetar med hållbarhet inom begränsade delar av organisationen har lågt eller inget förtroende hos representanterna. Viljan att handla nyproducerade hållbara plagg hindras av det faktum att respondenterna inte litar på graden av hållbarhet i produkterna och produktionskedjan. Greenwashing är ett begrepp samtliga respondenter är bekanta med vilket minskar förtroendet för företagen eftersom det är vanligt förekommande inom modebranschen. Samtliga respondenter efterlyser transparens hos företagen vilket skulle öka deras förtroende och vilja att konsumera hållbart.
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Brandt, Rasmus. "Polynomial Matrix Decompositions : Evaluation of Algorithms with an Application to Wideband MIMO Communications." Thesis, Uppsala universitet, Signaler och System, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-134389.
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The interest in wireless communications among consumers has exploded since the introduction of the "3G" cell phone standards. One reason for their success is the increasingly higher data rates achievable through the networks. A further increase in data rates is possible through the use of multiple antennas at either or both sides of the wireless links. Precoding and receive filtering using matrices obtained from a singular value decomposition (SVD) of the channel matrix is a transmission strategy for achieving the channel capacity of a deterministic narrowband multiple-input multiple-output (MIMO) communications channel. When signalling over wideband channels using orthogonal frequency-division multiplexing (OFDM), an SVD must be performed for every sub-carrier. As the number of sub-carriers of this traditional approach grow large, so does the computational load. It is therefore interesting to study alternate means for obtaining the decomposition. A wideband MIMO channel can be modeled as a matrix filter with a finite impulse response, represented by a polynomial matrix. This thesis is concerned with investigating algorithms which decompose the polynomial channel matrix directly. The resulting decomposition factors can then be used to obtain the sub-carrier based precoding and receive filtering matrices. Existing approximative polynomial matrix QR and singular value decomposition algorithms were modified, and studied in terms of decomposition quality and computational complexity. The decomposition algorithms were shown to give decompositions of good quality, but if the goal is to obtain precoding and receive filtering matrices, the computational load is prohibitive for channels with long impulse responses. Two algorithms for performing exact rational decompositions (QRD/SVD) of polynomial matrices were proposed and analyzed. Although they for simple cases resulted in excellent decompositions, issues with numerical stability of a spectral factorization step renders the algorithms in their current form purposeless. For a MIMO channel with exponentially decaying power-delay profile, the sum rates achieved by employing the filters given from the approximative polynomial SVD algorithm were compared to the channel capacity. It was shown that if the symbol streams were decoded independently, as done in the traditional approach, the sum rates were sensitive to errors in the decomposition. A receiver with a spatially joint detector achieved sum rates close to the channel capacity, but with such a receiver the low complexity detector set-up of the traditional approach is lost. Summarizing, this thesis has shown that a wideband MIMO channel can be diagonalized in space and frequency using OFDM in conjunction with an approximative polynomial SVD algorithm. In order to reach sum rates close to the capacity of a simple channel, the computational load becomes restraining compared to the traditional approach, for channels with long impulse responses.
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Ghazel, Ramzi. "Méthodes de caractérisation en bruit des dispositifs radiofréquences multi accès." Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0122.
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Dans tout système de télécommunication micro-onde, les performances en bruit représentent un critère très important des dispositifs des chaînes de réception. La connaissance des sources de bruit interne des composants et leur corrélation permet de prédire et optimiser les performances en bruit d’un récepteur. Ce thème fait l’objet de nombreuses études et publications à travers le monde. Le travail proposé dans cette thèse consiste à évaluer les performances en bruit d’un dispositif multiport (N-ports) au sens le plus général et sans aucune approximation, en se basant sur une nouvelle méthode d’extraction de l’intégralité de la matrice de corrélation des ondes de bruit qui contient tous les informations relatives aux performances en bruit. Cette nouvelle méthode est basée sur l’utilisation du formalisme des ondes de bruit et la matrice de répartition [S], les résultats d’extraction sont validés par des calculs et par des mesures sur deux dispositifs deux ports (passif et actif) et sur deux octopôles (4 accès) en mode standard et mixte (passif et actif)<br>In any microwave telecommunication system, noise performance is a very important criterion for receiving chain devices. Knowledge of the internal noise sources of the components and their correlation makes it possible to predict and optimize the noise performance of a receiver. This theme is the subject of numerous studies and publications around the world. The work proposed in this thesis consists in evaluating the noise performance of a multiport device (N-ports) in the most general sense and without any approximation, based on a new method of extracting the entire noise wave correlation matrix that contains all the information relating to noise performance. This new method is based on the use of noise wave formalism and the scattering matrix[S], the extraction results are validated by calculations and measurements on a two-port device (passive and active) and on a 4-port in standard and mixed mode (passive and active)
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Perez-Ramirez, Javier. "Relay Selection for Multiple Source Communications and Localization." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579585.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV<br>Relay selection for optimal communication as well as multiple source localization is studied. We consider the use of dual-role nodes that can work both as relays and also as anchors. The dual-role nodes and multiple sources are placed at fixed locations in a two-dimensional space. Each dual-role node estimates its distance to all the sources within its radius of action. Dual-role selection is then obtained considering all the measured distances and the total SNR of all sources-to-destination channels for optimal communication and multiple source localization. Bit error rate performance as well as mean squared error of the proposed optimal dual-role node selection scheme are presented.
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Perez-Ramirez, Javier. "An Opportunistic Relaying Scheme for Optimal Communications and Source Localization." International Foundation for Telemetering, 2012. http://hdl.handle.net/10150/581448.
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ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California<br>The selection of relay nodes (RNs) for optimal communication and source location estimation is studied. The RNs are randomly placed at fixed and known locations over a geographical area. A mobile source senses and collects data at various locations over the area and transmits the data to a destination node with the help of the RNs. The destination node not only needs to collect the sensed data but also the location of the source where the data is collected. Hence, both high quality data collection and the correct location of the source are needed. Using the measured distances between the relays and the source, the destination estimates the location of the source. The selected RNs must be optimal for joint communication and source location estimation. We show in this paper how this joint optimization can be achieved. For practical decentralized selection, an opportunistic RN selection algorithm is used. Bit error rate performance as well as mean squared error in location estimation are presented and compared to the optimal relay selection results.
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Tran, Tuan-Anh. "Multiple-input multiple-output optical wireless communications." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:094fbe23-88c3-49c4-b64b-a1de40674123.
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Visible-light optical wireless communications (OWC) is a potential technology that can help resolve the crowdedness of the radio-frequency bands, whilst conveniently exploiting energy-saving light-emitting diodes (LEDs) as transmitters for both illumination and communications. Since there usually are many LEDs in a lighting unit, OWC has a multi- input multi-output (MIMO) geometry which, thanks to its channel diversity, can offer wireless local networks at data-rates many times higher than possible with single-channel systems. In such systems, MIMO-detection methods to separate the different optical channels play an important role in improving the system performance by helping reduce cross-talk between channels. To measure the performance of a particular geometry for MIMO communications, a simulation study, reported in this thesis, found that, amongst the signal- independent metrics, the condition number may be used as a rough predictor of the performance, whilst the channel Signal-to-Interference-and-Noise Ratio (SINR) is the most appropriate for geometry assessment. Combined with the fact that the overall performance of a MIMO system is mostly dominated by its worst channel, this indicates that the most effective way to improve the system performance is to maximise the worst channel’s SINR. One of the possible solutions to improving the SINRs is to use holograms to steer the transmitter images such that their distributions over the photo-detectors reduce overlaps. As LEDs emit partially-coherent light, the beam steering has to be carried out with partially- coherent illumination. By using two lenses to parallelise and collect partially-coherent light before and after the hologram, respectively, the source and image intensity distributions, and the autocorrelation of the hologram can be related in a succinct mathematical relationship. This leads to the development of three computational algorithms based on the autocorrelation function to obtain a quantised hologram with the desired beam-steering capability. These algorithms have their cost functions and performance comparison done at the hologram plane instead of the image plane, which therefore takes less time than traditional image-based methods. Specifically, one of these algorithms is able to save significant time over both the other autocorrelation-based algorithms and the direct binary-search, by 33% and by 50% respectively. A simulation-based study and a corresponding experiment, both reported in this thesis, found that the one of the proposed algorithms had poor power efficiency, whilst the other two were both highly effective in generating digital holograms with precise and power-efficient beam-steering performance. Of these two algorithms, one had superior time performance and was likely the best of the three proposed autocorrelation-based algorithms for generating beam-steering holograms. MIMO-OWC simulation also demonstrated the capability of using beam-steering holograms to design the channel and improve the system performance. Combining reported findings, a strategy can be devised to optimise the throughput of an imaging MIMO-OWC system for a given transmitted power.
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Тимохіна, Яна Олександрівна, Яна Александровна Тимохина та Yana Oleksandrivna Tymokhina. "Управління комплексом маркетингових комунікацій промислового підприємства". Thesis, СумДУ, 2015. http://essuir.sumdu.edu.ua/handle/123456789/41863.
Full textAbstract:
Дисертація присвячена вдосконаленню управління маркетинговими комунікаціями промислового підприємства. У дисертаційній роботі запропоновано та обґрунтовано науково-методичний підхід до формування комплексу просування промислового підприємства. Запропоновано визначення поняття «синтезовані маркетингові комунікації» та класифікацію інструментів маркетингових комунікацій. Розвинено методичний підхід до планування маркетингової комунікаційної діяльності промислових підприємств за рівнями управління з використанням синтезованого інструментарію просування. Сформовано та обґрунтовано теоретико-методичний підхід до вибору маркетингової комунікаційної стратегії промислового підприємства на основі оцінювання ефективності комплексу просування та розрахунку синтезованого ефекту. Удосконалено організаційно-економічний механізм маркетингової комунікаційної діяльності вітчизняних промислових підприємств.<br>Диссертация посвящена усовершенствованию управления маркетинговыми коммуникациями промышленного предприятия. В диссертационной работе предложен и обоснован научно-методический подход к формированию комплекса продвижения промышленного предприятия с помощью синтезированных маркетинговых коммуникаций, использование которых даёт возможность сконцентрировать коммуникационные усилия на целевой аудитории, что повышает эффективность мероприятий по продвижению продукции. Установлено, что в основе дефиниций «интеграции» лежит понятие процеса, в то время как маркетинговая коммуникация в условиях высокой степени интеграционных процесов является сложным соединением разных инструментов, выражающих не процесс объединения, а целостность. Таким образом, к понятию «маркетинговая коммуникация» ближе понятие «синтеза», в основе понимания которого лежит единство, целостность объединенных и связанных между собой явлений. Предложено определение понятия «синтезированные маркетинговые коммуникации» как целостного соединения основных и синтетических инструментов продвижения, что обеспечивает синтезированный эффект в долгосрочной перспективе. Классификация инструментов маркетинговых коммуникаций по способу формирования комплекса продвижения, включающая массовые синтезированные и персонифицированные синтезированные коммуникации, демонстрирует природу их возникновения и содействует их использованию промышленными предприятиями. Получил дальнейшее развитие методический подход к планированию маркетинговой коммуникационной деятельности промышленных предприятий по уровням управления с использованием синтезированного инструментария продвижения, дающий возможность предприятию четко скоординировать кампанию продвижения таким образом, чтобы в течение всего срока кампании коммуникационные усилия были эффективными. Установлено соответствие элементов декомпозиции цели уровням управления, на которых они будут результирующими. Детализация целей по уровням управления и формирование комплекса продвижения отдельно для каждого уровня дает возможность предприятию сконцентрировать внимание на необходимых целях в конкретный промежуток времени и применять именно те коммуникационные инструменты, которые будут содействовать их достижению. Сформирован и обоснован теоретико-методический подход к выбору маркетинговой коммуникационной стратегии промышленного предприятия на основе оценки эффективности комплекса продвижения с использованием показателей экономической, коммуникационной и психологической эффективности и расчета синтезированного эффекта. Доказано, что использование такой системы показателей даёт возможность диагностировать недостатки комплекса маркетингових коммуникаций предприятия и своевременно корректировать инструментарий продвижения. Усовершенствован организационно-экономический механизм маркетинговой коммуникационной деятельности промышленных предприятий в части использования массовых и персонифицированных синтезированных маркетинговых коммуникаций, что на практике позволяет предприятиям осуществлять постоянный поиск новых форм объединения инструментария продвижения.<br>The thesis is devoted to improve management of marketing communications of industrial enterprises. The thesis proposed and substantiated scientific and methodical approach to promotion complex of industrial enterprise. Proposed definition of «synthesized marketing communications» and classification tools of marketing communication in the way of formation of promotion complex in mass synthesized communications and personalized synthesized communication. Developed methodical approach to planning marketing communication activities of industrial enterprise by management levels using synthesized marketing communications. Formed and grounded theoretical and methodological approach to the choice of marketing communication strategy of industrial enterprise on the basis of evaluating the effectiveness of promotion complex and calculating synthesized effect. Improved organizational-economic mechanism of marketing communication activities of domestic industry.