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Dissertations / Theses on the topic 'Outdoor channel'

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Published: 4 June 2021
Last updated: 14 February 2022

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1

Noronha, Joseph Ajay Neil. "Ultrawideband Channel Sounding Studies in Outdoor and Outdoor-Indoor Environments." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10006.

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Ultrawideband (UWB) is one of the most promising communication technologies in recent times with the promise of high data rates and spectral reuse. This work analyses the outdoor and outdoor-to-indoor propagating characteristics of the UWB pulse, which can be of the order of a few gigahertz in bandwidth. The aim of the thesis is to provide the parameters needed in order to develop a channel model for such cases. The channel model would then play an important role in determining physical layer (PHY) solutions to optimally exploit these characteristics. The measurements carried out on the Virginia Tech campus are used to compute parameters such as path loss, penetration loss and delay statistics. These are carried out in multiple frequency bands and the results are compared across frequency bands to determine effect of different frequency levels on the parameters. Finally the results are analyzed with respect to similar parameters obtained in other measurement campaigns in an attempt to evaluate the performance of Ultrawideband vis-à-vis narrowband systems.
Master of Science
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2

Smithson, Allan Geoffrey. "Wide area radio channel modelling across the indoor/outdoor interface." Thesis, University of Bath, 2005. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423492.

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3

Ahmed, Md Humayun. "Delay-line-multiplexer-based distributed antenna channel sounders for indoor and outdoor microcellular environments." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58673.

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Distributed Antenna Systems (DAS) are increasingly used to implement wireless access networks that provide high capacity, high reliability, and tailored coverage in both indoor and outdoor microcell environments. The third-generation DAS that have recently emerged are based on massively distributed antennas connected by fibre to transceiver hubs linked via a high-speed backplane. Such systems can be: 1) configured to operate in a variety of operating modes from small cells to Distributed MIMO and 2) highly customized based upon the nature of the environments and the performance demands of the users. Successful deployment of future Distributed Antenna Systems will require channel characterizations that capture our knowledge and understanding of the propagation impairments that degrade the airlink performance in a form useful in simulation and design. The principal challenge of DAS channel measurements is the need to characterize the signals presented by a multiplicity of distributed antennas in an effective and efficient manner. Most DAS channel sounders that have been reported in the literature to date are either based upon a multi-channel measurement receiver or a single-channel receiver equipped with a multi-throw RF switch. Each carries significant penalties in terms of cost and/or performance. Here, we present an alternative scheme that uses relatively inexpensive fibre-optic excess delay lines inserted into a conventional DAS distribution hub in order to effectively stack or multiplex signals in time so they can be presented in sequence by a conventional channel sounder equipped with a single-channel receiver. The concept is generally applicable, with appropriate modification, to channel sounders based upon: 1) Vector Network Analyzers that are commonly used to characterize short-range indoor environments, and 2) stepping or sliding correlators that are commonly used to characterize small cells in outdoor environments. In each case, we have derived system design formulas that allow one to determine the excess delay required to provide adequate temporal separation between the individual channel responses and system error models that allow cross-talk and other effects that may be present in the fiber distribution hub to be characterized. Finally, we have demonstrated proof-of-concept implementations of both in laboratory, real-world indoor, and outdoor small cell environments.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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4

Picorone, Antonio Angelo Missiaggia. "Comunicação digital em canais PLC: técnicas de transmissão, detecção e caracterização de canais PLC outdoor brasileiros." Universidade Federal de Juiz de Fora (UFJF), 2014. https://repositorio.ufjf.br/jspui/handle/ufjf/4168.

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Esta tese discute a medição e a caracterização das redes de distribuição de energia elétrica de baixa tensão (RDE-BT) e externa (outdoor) como meio de comunicação de dados para sistemas power line communication (PLC). São apresentados e discutidos diversos parâmetros obtidos a partir de uma campanha de medição realizada na RDE-BT de uma concessionária brasileira. Dentre os parâmetros analisados destacam-se o tempo de coerência, banda de coerência, espalhamento do atraso, comprimento da resposta ao impulso do canal e capacidade do canal, quando se considera as bandas de frequências de 1,7 a 30 MHz, 1,7 a 50 MHz e 1,7 a 100 MHz. As análises estatísticas evidenciam o potencial da rede de energia elétrica como meio de comunicação e discute os limites dessa potencialidade. Além disso, são propostos modelos de densidade espectral de potência dos ruídos, caracterização esparsa de canais PLC e proposto um modelo para geração de canais PLC variantes no tempo, cujo tempo de coerência entre as realizações dos canais é controlado. A estimação de canais PLC é apresentada como uma oportunidade de aplicação das técnicas de amostragem compressiva. Os resultados relacionados com as modelagens propostas constituem um ferramental de grande utilidade para projetar e analisar o desempenho de sistemas PLC.
This dissertation aims at discussing the measurement and characterization of outdoor electric power grid of low voltage as communication medium (power line communication - PLC). Statistical analyses carried out on several parameters such as average channel gain, coherence time, coherence bandwidth, delay spread, length of the channel impulse response, and channel capacity, when it is considered the frequency bands from 1.7 to 30 MHz, from 1.7 up to 50 MHz, and from 1.7 up to 100 MHz, are presented. These analyses reveal the circumstances in which outdoor and low-voltage electric power grids can be advantageous to support a reliable and efficient PLC system operation. Moreover, power spectral density models of additive noise and sparse representation of PLC channels are proposed. Also, a PLC time-varying channels model generator that makes use of coherence time is introduced. The proposed model generator, which is validated with measured PLC channels, is an effective tool to carry out performance analysis of PLC systems. Finally, PLC channel estimation is highlighted as an opportunity for the application of compressive sampling-based techniques. The use of traditional OFDM - based channel estimation techniques and the ones based on compressive sensing gives some directions for advancing channel estimation techniques for PLC channels.
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5

Manan, Waqas. "Propagation channel models for 5G mobile networks. Simulation and measurements of 5G propagation channel models for indoor and outdoor environments covering both LOS and NLOS Scenarios." Thesis, University of Bradford, 2018. http://hdl.handle.net/10454/17219.

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At present, the current 4G systems provide a universal platform for broadband mobile services; however, mobile traffic is still growing at an unprecedented rate and the need for more sophisticated broadband services is pushing the limits on current standards to provide even tighter integration between wireless technologies and higher speeds. This has led to the need for a new generation of mobile communications: the so-called 5G. Although 5G systems are not expected to penetrate the market until 2020, the evolution towards 5G is widely accepted to be the logical convergence of internet services with existing mobile networking standards leading to the commonly used term “mobile internet” over heterogeneous networks, with several Gbits/s data rate and very high connectivity speeds. Therefore, to support highly increasing traffic capacity and high data rates, the next generation mobile network (5G) should extend the range of frequency spectrum for mobile communication that is yet to be identified by the ITU-R. The mm-wave spectrum is the key enabling feature of the next-generation cellular system, for which the propagation channel models need to be predicted to enhance the design guidance and the practicality of the whole design transceiver system. The present work addresses the main concepts of the propagation channel behaviour using ray tracing software package for simulation and then results were tested and compared against practical analysis in a real-time environment. The characteristics of Indoor-Indoor (LOS and NLOS), and indoor-outdoor (NLOS) propagations channels are intensively investigated at four different frequencies; 5.8 GHz, 26GHz, 28GHz and 60GHz for vertical polarized directional, omnidirectional and isotropic antennas patterns. The computed data achieved from the 3-D Shooting and Bouncing Ray (SBR) Wireless Insite based on the effect of frequency dependent electrical properties of building materials. Ray tracing technique has been utilized to predict multipath propagation characteristics in mm-wave bands at different propagation environments. Finally, the received signal power and delay spread were computed for outdoor-outdoor complex propagation channel model at 26 GHz, 28 GHz and 60GHz frequencies and results were compared to the theoretical models.
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Weiler, Richard Jürgen [Verfasser], Slawomir [Akademischer Betreuer] Stanczak, Slawomir [Gutachter] Stanczak, Alexander [Gutachter] Maltsev, and Makoto [Gutachter] Ando. "Channel investigation of outdoor millimeter-wave access links / Richard Jürgen Weiler ; Gutachter: Slawomir Stanczak, Alexander Maltsev, Makoto Ando ; Betreuer: Slawomir Stanczak." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156184878/34.

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7

Magnusson, Jonas, Johan Olsson, and Benjamin Risom. "Cooperation in the distribution channel : Determinants of inter-organisational cooperation between suppliers and servicing dealers in the Swedish outdoor power equipment market." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Företagsekonomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16033.

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Background: For manufacturing suppliers, careful handling of business relationships with dealers is an essential function required for business success. End consumers rely on dealers for product information, advice and after sales support; all of which being factors capable of enhancing their perceived value of the product. The importance of the dealers for the end consumers implies that it is in the interest of suppliers to manage their relationship with the dealers in a satisfactory manner in order of gaining their support and commitment. In the case of suppliers in the Swedish market for outdoor power equipment, managing this relationship with servicing dealers is of great importance to their business success and viability. Successful management of such relationships requires coordination and cooperation. Thus, it is in the interest of suppliers to understand how long-term cooperation with dealers can be enhanced. Purpose: Our research focuses on identifying determinants that enhance sustainable cooperation between manufacturers and servicing dealers in the Swedish outdoor power equipment market. Method: A survey was conducted among servicing dealerships in Sweden testing eight hypotheses developed through an adaption of Morgan and Hunts’ (1994) Commitment-trust theory together with an extensive literature review. The results were ana-lysed and tested with correlation analysis. Conclusions: Trust and commitment were found to be determinants in fostering sustainable cooperation between dealers and manufacturers in the Swedish market for outdoor power equipment. Furthermore, four important antecedents for dealer commitment were identified; supplier commitment, support, termination costs and participation. Whereas, communication was found to be an important precursor for trust.
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8

Roivainen, A. (Antti). "Three-dimensional geometry-based radio channel model:parametrization and validation at 10 GHz." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526215549.

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Abstract This dissertation presents complete parameterizations for a three-dimensional (3-D) geometry-based stochastic radio channel model (GSCM) at 10 GHz based on measurement campaigns. The thesis is divided into the following main parts: radio channel measurements, the characterization of model parameters, and model validation. Experimental multiple-input multiple-output (MIMO) channel measurements carried out in two-story lobby and urban small cell scenarios are first described. The measurements were performed with a vector network analyzer and dual polarized virtual antenna arrays with a bandwidth over 500 MHz. The measurement data was post-processed using the ESPRIT algorithm and the post-processed data was verified using a semi-deterministic map-based model. The results showed a good match between estimated and modeled multipath components (MPCs). In addition, single-input single-output outdoor-to-indoor measurements were executed through a standard multi-pane glass window and concrete wall. A statistical analysis was carried out for defining full 3-D characterization of the propagation channel in both line-of-sight (LOS) and non-line-of-sight (NLOS) propagation conditions. The delay and angular dispersions of MPCs are smaller in comparison to lower frequency bands due to the higher attenuation of the delayed MPCs. Moreover, specular reflection is observed to be the more dominant propagation mechanism in comparison to diffuse scattering, leading to smaller cluster angle spreads in comparison to lower frequency bands. The penetration loss caused by a standard multi-pane glass window is on the same level as in the lower frequency bands, whereas the loss caused by the concrete wall is a few dBs higher than at lower frequency bands. Finally, the GSCM with determined parameters is validated. A MIMO channel was reconstructed by embedding 3-D radiation patterns of the antennas into the propagation path estimates. Equivalently the channel simulations were performed with a quasi deterministic radio channel generator (QuaDRiGa) using the defined parameters. The channel capacity, Demmel condition number, and relative condition numbers are used as the comparison metrics between reconstructed and modeled channels. The results show that the reconstructed MIMO channel matches the simulated MIMO channel well
Tiivistelmä Tämä väitöskirja esittää parametroinnit kolmiulotteiselle geometriaan perustuvalle stokastiselle radiokanavamallille 10 GHz:n taajuusalueella perustuen mitattuun radiokanavaan. Väitöskirja koostuu kolmesta pääalueesta: radiokanavamittaukset, radiokanavamallin parametrien määrittäminen ja mallin validointi. Aluksi kuvataan kaksikerroksisessa aula ja kaupunkipiensolu ympäristöissä monilähetin monivastaanotin (MIMO) järjestelmällä tehdyt kanavamittaukset. Mittaukset tehtiin vektoripiirianalysaattorilla ja kaksoispolaroiduilla virtuaaliantenniryhmillä 500 MHz kaistanleveydellä. Mittausdata jälkikäsiteltiin käyttämällä ESPRIT-algoritmia ja jälkikäsitelty data varmennettiin osittain deterministisellä mittausympäristön karttaan pohjautuvalla radiokanavamallilla. Tulokset osoittivat hyvän yhteensopivuuden mitattujen ja mallinnettujen moniteiden välillä. Lisäksi toteuttiin yksi-lähetin yksi-vastaanotin mittaukset ulko-sisä etenemisympäristössä monikerroksisen lasin ja betoniseinän läpi. Tilastollinen analyysin avulla määritettiin täysi kolmiulotteinen kuvaus radioaallon etenemiskanavasta näköyhteys ja näköyhteydettömässä tilanteissa. Moniteiden suuremmista vaimennuksista johtuen viive ja kulmahajonnat ovat pienemmät verrattaessa matalempiin taajuuksiin. Peiliheijastus on diffuusisirontaa merkittävämpi radioaallon etenemismekanismi johtaen pienempiin klustereiden kulmahajeisiin matalempiin taajuuksiin verrattuna. Monikerroksisen lasin läpäisyvaimennus on samankaltainen kuin alemmilla taajuuksilla, kun sitä vastoin betoniseinän vaimennus on muutaman desibelin suurempi kuin alemmilla taajuuksilla. Lopulta geometriaan perustava stokastinen radiokanavamalli validoidaan määritellyillä parametreilla. MIMO kanava uudelleen rakennetaan lisäämällä kolmiulotteiset antennien säteilykuviot estimoituihin radioaallon etenemisteihin. Vastaavasti radiokanava simuloidaan näennäisesti deterministisellä radiokanavageneraattorilla (QuaDRiGa) käyttäen määriteltyjä mallin parametreja. Kanavakapasiteettia, Demmel ehtolukua ja suhteellista ehtolukua käytetään vertailumittareina uudelleen rakennetun ja simuloidun kanavan välillä. Tulosten perusteella uudelleen rakennettu MIMO kanava on yhteensopiva simuloidun radiokanavan kanssa
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Ferreira, Ana Luiza Siqueira. "Análise de técnicas de detecção de sinais UWB em ambientes PLC." Universidade Federal de Juiz de Fora (UFJF), 2011. https://repositorio.ufjf.br/jspui/handle/ufjf/4104.

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O uso de banda ultra-larga (ultra wideband - UWB) vem sendo tema de pesquisa na área da comunicação sem fio há cerca de 20 anos e os bons resultados obtidos tem levado à introdução de novas tecnologias no mercado de transmissão de dados a curtas distâncias. No entanto, o uso de UWB para a transmissão de dados através da rede elétrica (power line communications - PLC) ainda é uma questão de investigação em aberto, interessante e promissora para um conjunto específico de aplicações que demandam elevada taxa de transmissão em curtas distâncias e baixo custo, tais como impressoras, monitores, etc. Neste contexto, a presente dissertação analisa diferentes aspectos da transmissão UWB através de cabos de distribuição de energia elétrica. Um sistema UWB impulsivo é analisado quando i) o canal PLC é outdoor, linear e variante no tempo; ii) o canal PLC é indoor, linear e invariante no tempo; iii) há ruído AWGN (additive white Gaussian noise) e iv) há ruído AIGN (additive impulsive Gaussian noise). Além disso, são respondidas questões referentes à adequação do pulso UWB ao canal de comunicação, considerando o espectro do mesmo quando o canal PLC é outdoor ou indoor. As modulações UWB investigadas são pela posição do pulso (pulse position modulation - PPM) e pela amplitude do pulso (pulse amplitude modulation - PAM). Além de apresentar diretrizes para o projeto de um sistema UWB para aplicações PLC, a presente dissertação analisa diversas estratégias e técnicas para recepção e redução da complexidade computacional do receptor UWB. Os resultados indicam que o uso de UWB é interessante para algumas aplicações específicas que envolvam elevada taxa de transmissão, através de curtas distâncias e baixo custo.
Ultra wideband modulation (UWB) has been a subject of research in the wireless field for nearly 20 years and the good results achieved have led to the introduction of new technologies in the market of short distances data communication. However, the employment of UWB for data transmission over power lines (PLC) is still an open, interesting and promising research theme for a specific set of applications which require high throughput over short distances and low cost, such as printers, computer monitors, etc. In this context, this dissertation examines several aspects of the UWB transmission through electricity distribution cables. An UWB impulsive system is analyzed when i) the PLC channel is outdoor, linear and time invariant; ii) the PLC channel is indoor, linear and time invariant; iii) there is AWGN (additive white gaussian noise) and iv) there is AIGN (additive impulsive gaussian noise) noise. Moreover, many questions regarding the adequacy of UWB pulse for the communication channel are answered, taking into account its spectrum when the PLC channel is outdoor or indoor. The UWB modulations investigated are pulse position modulation (PPM) and pulse amplitude modulation (PAM). Apart from presenting some guidelines to project a UWB system, this work analyzes different strategies and techniques for reception that reduce the computational complexity of the UWB receiver. The results point out that UWB is interesting for some specific applications which require high data transmission rate in short distances and low cost.
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Sundaram, Preethi. "New Results For Characterization Of Indoor Channels In Two Ism Bands (900-928 Mhz And 2.4-2.5 Ghz)." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1140462634.

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Palma, Lázgare Israel Romualdo. "Contributions to channel modelling and performance estimation of HAPS-based communication systems regarding IEEE Std 802.16TM." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/48630.

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New and future telecommunication networks are and will be broadband type. The existing terrestrial and space radio communication infrastructures might be supplemented by new wireless networks that make and will make use of aeronautics-technology. Our study/contribution is referring to radio communications based on radio stations aboard a stratospheric platform named, by ITU-R, HAPS (High Altitude Platform Station). These new networks have been proposed as an alternative technology within the ITU framework to provide various narrow/broadband communication services. With the possibility of having a payload for Telecommunications in an aircraft or a balloon (HAPS), it can be carried out radio communications to provide backbone connections on ground and to access to broadband points for ground terminals. The latest implies a complex radio network planning. Therefore, the radio coverage analysis at outdoors and indoors becomes an important issue on the design of new radio systems. In this doctoral thesis, the contribution is related to the HAPS application for terrestrial fixed broadband communications. HAPS was hypothesised as a quasi-static platform with height above ground at the so-called stratospheric layer. Latter contribution was fulfilled by approaching via simulations the outdoor-indoor coverage with a simple efficient computational model at downlink mode. This work was assessing the ITU-R recommendations at bands recognised for the HAPS-based networks. It was contemplated the possibility of operating around 2 GHz (1820 MHz, specifically) because this band is recognised as an alternative for HAPS networks that can provide IMT-2000 and IMT-Advanced services. The global broadband radio communication model was composed of three parts: transmitter, channel, and receiver. The transmitter and receiver parts were based on the specifications of the IEEE Std 802.16TM-2009 (with its respective digital transmission techniques for a robust-reliable link), and the channel was subjected to the analysis of radio modelling at the level of HAPS and terrestrial (outdoors plus indoors) parts. For the channel modelling was used the two-state characterisation (physical situations associated with the transmitted/received signals), the state-oriented channel modelling. One of the channel-state contemplated the environmental transmission situation defined by a direct path between transmitter and receiver, and the remaining one regarded the conditions of shadowing. These states were dependent on the elevation angle related to the ray-tracing analysis: within the propagation environment, it was considered that a representative portion of the total energy of the signal was received by a direct or diffracted wave, and the remaining power signal was coming by a specular wave, to last-mentioned waves (rays) were added the scattered and random rays that constituted the diffuse wave. At indoors case, the variations of the transmitted signal were also considering the following matters additionally: the building penetration, construction material, angle of incidence, floor height, position of terminal in the room, and indoor fading; also, these indoors radiocommunications presented different type of paths to reach the receiver: obscured LOS, no LOS (NLOS), and hard NLOS. The evaluation of the feasible performance for the HAPS-to-ground terminal was accomplished by means of thorough simulations. The outcomes of the experiment were presented in terms of BER vs. Eb/N0 plotting, getting significant positive conclusions for these kind of system as access network technology based on HAPS.
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El, Yakzan Adnan. "Performance prediction, parameter selection, and channel adaptation in the line-of-sight outdoors optical wireless channels using intelligent systems." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/59682/.

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With the increased usage of optical wireless communication, finding appropriate parameters for reliable transmission and providing efficient channel performance have become of challenging interest in research and industry. This has been a strong motivation to examine and develop methods and techniques to find suitable link parameters to increase the channel availability. This thesis is mainly concerned with designing, implementing and adapting intelligent algorithms to solve for parameter selection, channel prediction, and channel adaptation in dynamic optical wireless channels. The problem could be solved with other methods such as binary and sequential search; however, intelligent systems have the ability to find optimal results with more reliability, time efficiency and increased flexibility. The research focuses on single and multi-objective selection techniques using application-specific genetic algorithm (ASGA) in the outdoors line-of-sight (LOS) optical wireless channel where parameters have different effects on the channel performance and may affect the behaviour of other channel parameters. The technique is well-established at pre-installation stages of the channel, and could be also applied at run-time if a reconfigurable hardware is installed. An intelligent system, which uses a genetic algorithm predicted and optimized optical wireless channel in the (LOS) field, is presented. The prediction technique is proposed to estimate the bit error rate (BER) at the receiver, and suggests appropriate selection of link parameters. In this research, the work is developed based on on-off keying (OOK) modulation, and makes use of different weather conditions for channel modeling. A first attempt is made with a GA-based selection for transmission wavelengths (700nm to 1600nm), the overall deterministic attenuations being estimated by a visibility model, where the changes in visibility decide about the wavelength control margin. The research is then extended to consider various external link parameters scaled by look-up tables that meet the optical wireless industry. It shows that the transmission power should not always be the only costin the channel, and there are other parameters worthy of control. Principal Component Analysis is applied targeting the ASGA selected datasets to extract the contribution of each parameter to the output, and the implicit relations that exist among data sets to achieve a certain bit-error-rate. An Artificial Neural Network (ANN) is then applied to the channel for BER prediction; this may also validate the pre-installation advice done by PCA. Finally, a two-stage modelling using a neuro-fuzzy hybrid algorithm used for adapting the channel by monitoring the link range and total attenuations in the channel. Through analysing the simulation results using these intelligent systems algorithms, the thesis aims at providing maximum utilization of channel parameters for achieving optimum channel performance and increased availability under the application of various intelligent systems, which demonstrate their efficiency and effectiveness as compared with other techniques.
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Lim, Hong Meng. "On the average capacity of MIMO channels in outdoor multipath urban environments." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420409.

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Hicks, Trevor J. "Time spread characterization of outdoor microcellular and indoor wireless 1.9 GHz radio channels." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq20651.pdf.

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15

Garcia, Heriberto. "The value of outdoor education." CSUSB ScholarWorks, 2003. https://scholarworks.lib.csusb.edu/etd-project/2314.

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Witthohn, Anna-Lena. "Outdoor Learning as a Chance for Preschool Children to become a ´We´ and an ´I´ : Preschool Teachers´ Perception towards Outdoor Learning in Swedish Preschools." Thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177847.

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The study investigates preschool teachers’ individual perceptions towards outdoor learning in Swedish preschools. The aim is to understand how preschool teachers describe outdoor learning and which effects on children´s behavior are recognized. Furthermore, the study aims to highlight children particularly benefiting from learning outdoors. Therefore, semi-structured interviews following a qualitative research approach are hold in order to outline and evaluate the perceptions of seven preschool teachers working in southern Sweden. A literature review should allow a contextual location focusing on outdoor education and outdoor learning, the Swedish preschool curriculum, nature´s influence on human’s health and well-being and children with special needs. The interviews show that preschool teachers mainly recognize positive effects of learning outdoors regarding children´s social, emotional, cognitive and physical development. Outdoor learning offers children possibilities to play in bigger groups and seems to cause less conflicts. Little attention is put on negative effects only regarding outdoor surroundings. Preschool teachers identify two main character traits of children certainly benefiting from learning outdoors, referring to children needing increased movement and children indoors appearing shy and introverted. As possible explanations for positive effects of outdoor learning on children the preschool teachers mainly relate to larger space and increased feelings of freedom. Nature seems to provide possibilities for a lower distraction of the senses, allowing a clearer perception. Children´s ability to concentrate seems to increase through nature. Additionally, outdoors the opportunity of taking a timeout increases in order to allow children spending time alone.
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Irwin, David Brian. "Weaving the threads of education for sustainability and outdoor education." Thesis, University of Canterbury. Educational Studies and Human Development, 2010. http://hdl.handle.net/10092/3637.

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Sustainability has become a buzz word of our time, although our developed world community is still coming to terms with what the word really means. Universities and polytechnics in Aotearoa New Zealand will have to change in many ways before sustainability can be considered to occupy a meaningful place in the tertiary education sector. However the change process that sees an organisation moving towards sustainability is complex, and agency for change can be considered on many different levels including the individual identities of staff and students, the identity of managers, and the programme and wider organisational identities constructed by the communities that comprise them. This qualitative research explores education for sustainability within the context of outdoor education using the Bachelor of Adventure Recreation and Outdoor Education (BRecEd) at the Christchurch Polytechnic Institute of Technology (CPIT) (the programme into which the author teaches) as a case study. Participatory action research forms the overarching methodology for a multiple method approach to data collection. The research leans heavily on the lived experiences of staff and students within the programme, is woven with my own reflections, and incorporates many examples of students’ work. The weaving together of these experiences grounds the research and helps bring theory to life. The research reveals the complexity of change towards more sustainable ways of practising outdoor education in an organisational setting. It explores the tensions that are encountered and mechanisms that have allowed for staff and students to engage in education for sustainability in a more meaningful way. The key themes of the research explore the intersection of identity construction processes and change agency, and it is argued these processes are inseparable for those concerned with organisational change towards sustainability.
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18

Kurri, Prasada Reddy. "Root Mean Square-Delay Spread Characteristics for Outdoor to Indoor Wireless Channels in the 5 GHz Band." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1305119898.

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19

Kern, Heidi. "Nutzen und Chancen des Outdoor-Trainings eine Methodentriangulation zur Überprüfung des Praxistransfers im betrieblichen Kontext /." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=969740034.

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20

Khalid, Waqas. "Energy Usage prediction model comparing Indoor Vs. Outdoor Ice Rinks." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91164.

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Indoor ice rinks use 1091 MWh per annum for ice hockey based on statistics from over 100 Swedish ice rinks (Stoppsladd, 2011).The refrigeration system contributes 35 to75%( (Rogstam, 2010) of total energy usage in ice rinks with average value of 43% (Stoppsladd, 2010) for indoor to 75% for outdoor ice rinks. The basic aim of project is to reduce energy consumption in Swedish ice rinks and scope is for indoor and outdoor ice rinks in cold and mild summer climatic conditions like Sweden. To achieve target of energy reduction in ice rinks actual heat loads on outdoor bandy ice rink are being estimated along with performance analysis of refrigeration machine. The refrigeration system, heat loads on ice surface and their correlation is studied and analyzed in detail for Norrtälje Outdoor bandy ice rink for four warm days and whole season 2010-2011. The tricky and significant task of validation of input climate data for accurate heat loads calculations is completed with Swedish Metrological & Hydrological (SMHI) climate model data, correlations and related web based geographical data. The heat loads (conductive, convective and radiant) on outdoor bandy ice rink are calculated through thermodynamic relations with validated input climate data and measurements where as refrigeration system performance is monitored and analyzed with ClimaCheck(CC) instrumentation. The average cooling capacity is calculated for four warm days by CC internal method and actual cooling energy produced is obtained by practically assumed COP of system with aid of MYCOM compressor software. The cooling capacity and heat loads on ice surface are compared and analyzed considering energy usage affecting parameters and weather parameters like temperature, wind speed, relative humidity and solar load. The convection and condensation are contributing 75%, radiation 18%, ice resurfacing 4% and ground and header heat gain 3% to total heat loads on ice sheet for whole season. The deviation between total cooling energy produced by refrigeration machine and total heat load energy is found 19% and 27% for four warm days and whole season 2010-2011.The deviation is due to overestimation of heat losses from compressor’s body, compressor’s on and off operations, overestimated radiation heat load due to unmeasured negative radiation and lack of actual ice resurfacing heat load evaluation. The developed model in MS Excel allows comparison of field climate data with SMHI model data, indoor and outdoor ice rinks in terms of predicted energy usage by refrigeration system and in total and acts as decision tool to choose for building an indoor/outdoor ice rink.
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21

Nouri, Andre Naghi Lopes dos Santos. "Addressing urban outdoor thermal comfort thresholds through public space design." Doctoral thesis, Universidade de Lisboa, Faculdade de Arquitetura, 2018. http://hdl.handle.net/10400.5/16887.

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Tese de Doutoramento em Urbanismo, com a especialização em Urbanismo apresentada na Faculdade de Arquitetura da Universidade de Lisboa para obtenção do grau de Doutor.
Na cidade contemporânea, factores como as elevadas temperaturas e a intensidade dos efeitos da ilha de calor em meio urbano, têm vindo a revelar proeminente desconforto térmico e importantes preocupações com a saúde durante os períodos anuais de maior estímulo térmico. Para além destes riscos já existentes e inerentes ao clima urbano, as projecções das alterações climáticas apontam para uma exacerbação destes factores de risco ao longo do Séc. XXI. Muito embora as avaliações e outputs top-down tenham revelado informação de carácter imperativo relativamente a tais fenómenos, a emergência da agenda de adaptação às alterações climáticas veio também incentivar a comunidade científica internacional a maturar e a desenvolver abordagens bottom-up mais incisivas, com vista a fazer frente aos factores de risco locais. Assim sendo, a perspectiva de "localidade" tem vindo a ganhar um novo significado para disciplinas como o urbanismo e o design urbano, quando confrontados com aspectos como a segurança, o conforto térmico humano e a prosperidade do meio urbano contemporâneo. Todavia e, atendendo ao seu carácter emergente, as abordagens bottom-up ainda se encontram numa fase inicial e, consequentemente, relativamente limitadas, tendo em conta a distância existente entre a teoria e a aplicação prática. Como resposta, esta tese efectua uma abordagem bottom-up e uma reflexão acerca do modo como a união entre a climatologia urbana e o design do espaço público urbano, enquanto campos distintos, pode ser fortalecida. Tal fortalecimento visa investigar de forma directa sobre a possibilidade de "localmente", o conforto térmico humano em meio urbano exterior, ser melhorado através de práticas interdisciplinares apoiadas no conhecimento científico. Tendo em consideração o caso de Lisboa, esta investigação analisa a forma como esta abordagem pode suplantar questões como a incerteza climática/aplicacional e, consequentemente: (i) traduzir-se em linhas de orientação para o urbanismo e para o design urbano local, que poderão ser aplicadas/implementadas em múltiplas circunstâncias e contextos urbanos; visando ainda, (ii) auxiliar especialistas "não-climatólogos" a realizar levantamentos bioclimáticos (baseados em dados locais e/ou na informação obtida a partir da estação meteorológica) com o intuito de determinar/atenuar os factores de risco de stress associados ao calor e ao frio num determinado contexto exterior. Consequentemente e, focado numa abordagem bottom-up que para além disso considera outputs relevantes a partir de avaliações top-down, o design do espaço público é retratado como sendo uma ferramenta indispensável, com vista a assegurar "localmente" um meio urbano activo, confortável e seguro, tanto no presente, quanto num futuro que se afigura incerto.
ABSTRACT: Within the existing city, factors such as elevated urban temperatures and intensities of urban heat island effects are already revealing prominent thermal discomfort and health concerns during annual periods of more accentuated climatic stimuli. In addition to these exiting risks upon the urban microclimate, climate change projections indicate further exacerbations of such risks factors throughout the course of the twenty-first century. Although top-down assessments and disseminations have revealed imperative information with regards to such phenomena, the emergence of the climate change adaptation agenda has also arguably propelled the scientific international community to further mature bottom-up approaches to address local risk factors. As such, the perspective of ‘locality’ has been one which has gained new meaning for disciplines such as urban planning and design when considering the climatic safety, human thermal comfort, and prosperity of the contemporary public realm. Nevertheless, and resultant of its emerging nature, bottom-up approaches are still somewhat limited in terms of its existing breadth between theory and application and practice. As a response, this thesis undertakes a bottom-up approach and discusses how the union between the individual fields of urban climatology and public space design can be fortified. Such a fortification is directly aimed at investigating how local outdoor human thermal comfort can be improved through an interdisciplinary practice which is backed by scientific know-how and practice. Considering the case of Lisbon, this research deliberates upon how such an approach can overcome issues of climatic and applicative uncertainty, and can: (i) be translated into local design and planning guidelines which can be applied within numerous different urban circumstances; and (ii) aid non-climatological experts to undertake bioclimatic surveys (based both upon site and/or meteorological station data) to determine, and attenuate, local heat and cold stress risk factors within a particular outdoor context. Accordingly, and centred upon a bottom-up approach, which moreover considers important disseminations from top-down assessments, public space design is portrayed as an imperative tool to locally ensure an active, comfortable and safe public realm, both presently, and in an uncertain future.
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22

Compier, Tobias, and Raatikainen Niina. "Digitalizing Product & Brand Education to thrive in Digital Transformation : -The case of retail companies in the outdoor industry." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448483.

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The increasing development in digital transformation in the last decade has affected retail companies in the outdoor industry. The outbreak of the Covid-19 pandemic is further accelerating the outdoor industry ́s mindset towards digital solutions. New innovations such as online training, video content and digital educational platforms provide retail outdoor companies with opportunities to move from physical product & brand education routines to digitally based solutions. The purpose of this study is therefore to explore how the last years developments in digital transformation have impacted retail outdoor companies' way of working with product & brand education for their store staff, and if the Covid-19 pandemic has had any effects upon this. In addition, the research aims to find out what attitude retail outdoor companies have towards digital educational platforms, as a new innovation tool. In order to adequately explore the aim of this study a mixed research method was undertaken, combining both qualitative and quantitative analysis. The data was collected using an online questionnaire with respondents working for retail outdoor companies across Europe.  The outcomes of this study can be used for organizations that want to explore the opportunities of digitalizing their way of working with product & brand education. The findings suggest that digital product & brand education solutions have the potential to act more as a great complement to traditional physical education, than to actually replace it. Furthermore, the effects that the Covid-19 pandemic have had upon this has been contradictory and far from united. In addition, the findings indicate that retail outdoor companies have a positive attitude towards digital educational platforms, which suggest that there might be an increasing interest for digital educational platforms in the upcoming future.
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23

Cook, Elizabeth. "An Examination of Seasonal Shifts in Climate and Visitation, and Perspectives on Seasonal Shifts and Climate Adaptation Strategies in Tourism and Recreation Businesses for Moab, Utah." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7485.

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The city of Moab, an outdoor recreation hub in eastern Utah, has been encountering both shifts in the seasonality of visitation, and increases in tourist visitation, even with summer temperatures above the normal high. Tourism research describing the effects of climate change on the outdoor recreation industry has focused on winter, snow-dependent activities, while studies in Moab city have focused on the economic value of outdoor recreational activities. Few studies have described the relationship between seasonal tourism and climate change for arid desert locations. The purpose of this study is to describe how the tourism and recreation industry in Moab, Utah is experiencing and adapting to changes in climate. The first part of the research is a regression analysis of existing data, exploring the correlation between monthly national park visitation and climate factors (long-term monthly average temperature and temperature anomaly) that influence tourism seasonality in Arches National Park and Canyonlands National Park. Using an online survey, the second part of the research identifies how seasonality shifts are perceived by different actors in Moab and how they are responding to manifestations of climate change. Regression results indicate that as temperature increases in the region around Moab, national park visitation also increases. Moab businesses are not directly adapting to climate change, but are adapting to perceived increases in visitation throughout the year. The majority of Moab businesses do not attribute the increase in visitation to climate variables, instead visitation increases are believed to be a result of the popularity of the town and the region.
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24

Riffel, Alvin Daniel. "Effects of a dialogical argumentation based instruction on grade 9 learners' conceptions of a meteorological concept: Cold Fronts in the Western Cape, South Africa." Thesis, University of Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6262_1384164748.

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This study looks at the effects of a dialogical argumentation instructional model (DAIM) on grade 9 learners understanding of selected meteorological concepts: Cold fronts in the Western Cape of South Africa. Using a quasi-experimental research design model, the study employed both quantitative and qualitative (so-called &lsquo
mixed methods&rsquo
) to collect data in a public secondary school in Cape Town, in the Western Cape Province. A survey questionnaire on attitudes and perceptions towards high school as well as conceptions of weather was administered before the main study to give the researcher baseline information and to develop pilot instruments to use in the main study.
 
The study employed a dialogical instructional model (DAIM) with an experimental group of learners exposed to the intervention, and recorded differences from a control group which had no intervention. Learners from the two groups were exposed to a meteorological literacy test evaluation before and after the DAIM intervention. The results from the two groups were then compared and analysed according to the two theoretical frameworks that underpin the study namely: Toulmin&rsquo
s Argumentation Pattern - TAP (Toulmin, 1958) and Contiguity Argumentation Theory - CAT (Ogunniyi, 1997).
 
Further analyses were conducted on learners&rsquo
beliefs and indigenous knowledge, according to their conceptual understanding of weather related concepts used in the current NCS (National Curriculum Statement). 
After completing the study some interesting findings were made and based on these findings certain recommendations were suggested on how to implement a DAIM-model into classroom teaching using Indigenous Knowledge (IK). These recommendations are suggestions to plot the way towards developing a science&ndash
IK curriculum for the Natural Sciences subjects in South African schools.
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25

Rindhagen, Cecilia. "Skogsmulle, en miljökämpe? : En kvalitativ studie om hur miljöengagemang hänger ihop med friluftsliv." Thesis, Linnéuniversitetet, Institutionen för idrottsvetenskap (ID), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-103748.

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Inledning: Friluftsliv har en stark ställning i Sverige. Argumenten är positivt landade och innefattar vanligen både folkhälsa och miljöengagemang. Samtidigt som intresset ökar och fler vistas i naturen kommer rapporter om nedskräpningsproblem. Något som slår hål på uppfattningen om att friluftsliv främjar miljöengagemang. Syfte: Genom att undersöka hur ledare inom Friluftsfrämjandet ser på miljöengagemang och friluftsliv har studien som mål att skapa en teoretisk modell som visar förutsättningar alt. hinder för pronaturellt beteende, viljan att minska klimatavtrycket. Metod: Studien är en kvalitativ intervjustudie. 8 ledare inom Friluftsfrämjandet deltog. Genom Grounded Theory utformades en analysmodell som i sin tur konstruerade en visuell teoretisk modell.  Resultat: Miljöengagemanget är i första hand situationsanpassat och bygger på att plocka skräp. Miljöfokus varierar för olika typer av aktiviteter. Ju mer abstrakt naturen blir, desto svårare att förhålla sig till ett miljöengagemang. Glapp uppstår utifrån viljan att vara miljövänlig till den faktiska insatsen. Miljöengagemanget är inte tydligt utanför ledarrollen. Ifall engagemanget får fäste utanför organisationen är detta kopplat till friluftslivet som i sig kan innehålla miljöfokus.  Diskussion: Att friluftsliv skulle vara förenat med ökat miljöengagemang fungerar bättre i tanken än i praktiken. En möjlig väg kan vara att sammankoppla begreppen om allemansrätten hade ett tydligare ställningstagande.
Introduction: Outdoor recreation has a strong position in Sweden. Engaging in outdoor recreation is positively charged, includes public health and environmental engagement. When interest in outdoor recreation increases there are reports of garbage problems in natural areas. This suggest that outdoor activities doesn´t promotes environmental commitments. Aim: By investigating how voluntary guides within the Swedish Outdoor Association give reasons for environmental engagement through outdoor recreation, the study aims to create a theoretical model that shows the conditions for pronatural behavior. Method: The study was conducted as a qualitative interview study. 8 guides participated. Through Grounded Theory, an analysis model was designed which in turn constructed a visual theoretical model. Result: Environmental engagement is situational and focus on picking garbage. How environment priority is conducted differs within different types of activities. The more abstract nature becomes, the more difficult it is to relate to environmental engagement. Gaps arise from being environmentally friendly to the actual effort. If commitment takes root outside the organization, this is linked to the outdoor activities, which can include an environmental focus. Discussion: That outdoor recreation promotes environmental engagement is better in thought than in practice. The right of public access should have a clearer environmental position.
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26

Louise, Breman, and Svensson Andreas. "FUKTSKADOR I UTELUFTSVENTILERAD KRYPGRUND : Med avseende på klimatförändringar och installation av golvvärme." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-31087.

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Syfte: Idag riskerar cirka 300 000 hushåll med uteluftsventilerad krypgrund att bli angripna av fukt- och mögelskador. Klimatet i en uteluftsventilerad krypgrund påverkas i stor grad av temperaturen och den relativa luftfuktigheten. Det råder inga tvivel om att klimatet står inför förändringar, vilket innebär en höjd temperatur och en förändring av den relativa luftfuktigheten. Detta gör att den uteluftsventilerade krypgrunden inte har möjlighet att torka ut under vissa perioder på året och utsätts då för en förhöjd risk av fuktskador. Parallellt med klimatförändringen moderniseras även uppvärmningssystemen i småhusen, vilket ändrar förutsättningar för krypgrunderna. Målet med arbetet är att undersöka om klimatförändringarna och installation av golvvärme i träbjälklaget har bidragit till fuktskador i uteluftsventilerade krypgrunder och ge underlag till effektivare åtgärder av fuktskador. Metod: För att utreda om klimatförändringarna är ett problem för de uteluftsventilerade krypgrunderna har dokumentanalyser genomförts vilka sedan följdes av beräkningar av krypgrundens relativa luftfuktighet. På samma sätt gavs svar på om golvvärmen är en bidragande faktor till fuktskadorna. Båda frågeställningarna styrktes även av kvalitativa intervjuer med sakkunniga personer. Hur fuktskadorna effektivare kunde åtgärdas togs främst fram genom kvalitativa intervjuer men styrktes av dokumentanalyser. Resultat: Studien visar att klimatförändringarna kommer att påverka uteluftsventilerade krypgrunder i positiv bemärkelse då studien endast tog hänsyn till temperaturhöjningen. Installation av golvvärme har även visats vara positivt mot fuktskador i en uteluftsventilerad krypgrund om isolering i bjälklaget saknas eller är bristfällig. Branschen ser ingen vinst i att effektivisera åtgärdsmetoderna då dessa redan är välprövade och väl fungerande. Konsekvenser: Ett varmare klimat ger bättre förutsättningar för en uteluftsventilerad krypgrund. Medvetenheten om hur klimatförändringarna påverkar krypgrunderna ger byggbranschen ett försprång att förbereda sig inför kommande förändringar. Kunskapen om att golvvärme kan ge positiva effekter mot fuktskador i uteluftsventilerade krypgrunder ger nya förutsättningar för renoveringar och åtgärder mot fuktskador, dock måste energiförlusterna tas i hänsyn i dessa fall. Branschen ser ingen vinst i att effektivisera åtgärdsmetoderna, vilket gör att det inte finns någon anledning att gå djupare in i detta. Begränsningar: Arbetet behandlar endast uteluftsventilerade krypgrunder med träbjälklag som ligger inom Sveriges gränser. Denna studie är därför inte applicerbar på andra konstruktioner eller utanför Sveriges gränser. Endast klimatförändringarna det senaste seklet och fram till 2100 tas hänsyn till i rapporten. Studien tar heller inte hänsyn till fukttillskott från mark och dagvatten, likaså görs inga beräkningar på ventilation.
Purpose: Today are about 300 000 buildings with outdoor ventilated crawl space at risk to be contaminated by moisture and mold damage. An outdoor ventilated crawl space’s climate is greatly affected by the temperature and the relative humidity. There is no doubt that the climate is facing changes, which means an increased temperature and a change in the relative humidity. This prevents the outdoor ventilated crawl space from drying out during certain periods of the year and is then exposed to a heightened risk of moisture damage. Parallel to the climate change the heating systems are being modernized in houses, which changes the conditions for the crawl spaces. The objective of this essay is to do a research if climate change and the installation of underfloor heating in the greater part of the joist area has given rise to moisture damage in outdoor ventilated crawl spaces and provide good basis for more effective measures to moisture damage. Method: To investigate whether the climate change is a problem for outdoor ventilated crawl spaces have document analyzes been conducted, which was followed by calculations of the crawl spaces’ relative humidity. Calculations have been made to find out if the underfloor heating is a contributing problem to moisture damage. Both issues are also corroborated by interviews with qualified people. How the moisture damage more effective could be fixed was answered primarily through qualitative interviews, but corroborated by document analysis. Findings: The study shows that climate change will affect outdoor ventilated crawl spaces in a positive sense, only account to the temperature rise. Installing underfloor heating has also been shown to be positive against moisture damage in outdoor ventilated crawl spaces if insulation in the soffit is missing or deficient. The industry sees no gain in efficiency action methods as these are already proven and well- functioning. Implications: A warmer climate provides better conditions for outdoor ventilated crawl space. Being aware of the changes associated with climate change, and its effects on buildings give the construction industry a head start to prepare for future changes. Knowledge that underfloor heating can provide positive effects against moisture damage in crawl spaces creates new opportunities for renovations and actions against dampness but the energy losses in this case must be considered. Since the industry does not see profit in streamlining action methods is no need to go deeper into this. Limitations: The report deals only outdoor ventilated crawl spaces with wooden soffit that is located within the Swedish borders. This study is therefore not applicable to other constructions or other countries. Only climate change in the last century and up until 2100 are taken into account in the report. Further on the study does not take the excess moisture from the soil or the storm water into account; likewise there are no calculations for the ventilation.
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27

Bjurling, Ella, and Emilia Swanson. "Kundens relation till plagget : En studie kring hur ett friluftsföretag genom sin kommunikation kan förlänga plaggens livslängd." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-26591.

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Syfte: Studiens syfte är att undersöka hur ett friluftsföretag genom sin kommunikation kan skapa ett långvarigt och hållbart produktvärde för sina kunder, med avsikt att förlänga produktens livslängd. Studiens resultat kan förhoppningsvis bidra med information och kunskap till företag och branschorganisationer om hur man skapar eller kommunicerar långvarigt produktvärde. Studien har utgått från ett marknadskommunikation och- konsumtionsbeteende perspektiv. Metod: En kombinerad metod bestående av kvalitativa intervjuer och en kvantitativ kundundersökning har utförts för insamling av empiri. Intervjuguide och kundundersökning har utgått från fyra centrala begrepp, vilka var konsumtionsbeteende, kunskap kring hållbarhet, marknadskommunikation och produktvärde. Resultat: Studiens resultat visar vikten av att företaget känner sin kundgrupp och dess kunskapsnivå kring hållbarhetsfrågor. Därefter bör kommunikation anpassas och göras enkel att ta del av. För att motivera kunden till att vårda sina plagg bör kommunikation gällande klimatpåverkan, reparationsmöjligheter och enkla tips för tvätt och impregnering kommuniceras kontinuerligt. God service från företaget innefattande lång garanti är även en faktor som kan förlänga produktens livslängd. Relevans: Studien bidrar med relevanta utgångspunkter för hur kommunikation kan förlänga tiden ett plagg används av den primära kunden vilket i sin tur kan leda till minskad konsumtion. Enbart ett friluftsföretags kundgrupp har studerats, vilket öppnar upp för vidare forskning där jämförelser mellan två företag kan genomföras. I detta fall vore det önskvärt att jämföra företag som tydligt kommunicerar hållbarhetsfrågor med företag som ej gör det. I en sådan jämförelse kan eventuella likheter och skillnader i kundgruppernas konsumtionsbeteende identifieras.
Purpose: The purpose of the study is to examine how an outdoor company, through it's communication, can create a long lasting, durable and sustainable product value for its customers, with the intention of increasing the product life span. The result of the study can hopefully contribute with information and knowledge for companies and industry organizations on how to create or communicate a long lasting product value. The study has been based on a marketing communication and consumption behavior perspective.  Method: A mixed method of qualitative interviews and a quantitative survey was carried out for collection of data. The interviews and survey were contracted out of four key words, which were consumer behavior, sustainable knowledge, marketing communication and product value.  Findings and conclusion: The findings of the study shows the importance of the company knowing it's target audience and what level of sustainability knowledge they possess. Regarding this, the communication should be adjusted and easily available. To motivate the customer to care and repair their garments communication regarding climate impact, possibilities for repair and easy tips on washing and impregnation should be communicated continuously. Service in the form of a long guarantee is also of value when trying to increase the product life span.  Relevance: The study contributes relevant points on how communication can lengthen the user time of a garment by the primary customer, which can lead to a decrease in consumption. Only one outdoor company was studied, which opens up opportunities for further research where more companies could be studied. In this case it would be worthwhile to compare companies with a clear sustainable communication profile, to companies without one. This kind of comparison could show eventual similarities and differences in consumer behavior.
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28

Basham, Jennifer Elizabeth. "The Effects of an Overnight Environmental Science Education Program on Students' Attendance Rate Change for Middle School Years." PDXScholar, 2015. http://pdxscholar.library.pdx.edu/open_access_etds/2730.

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Programs that engage middle students in participatory, real-world, and hands-on field based instruction can be a powerful asset to the educational experiences for students; motivating and inspiring some to appreciate and value school in a different way. Overnight environmental science programs have a unique opportunity to support students by creating experiences where students can participate in learning in vastly different ways from what they may engage with in the traditional 4-walled classroom, while concurrently developing a relationship with the natural world. Decreasing educational budgets and increased need to substantiate educational programs in terms of their impact on students has added pressure for overnight environmental science programs to validate their impact through quantitative means. Utilizing overnight environmental science education program attendance records and merging them with school district data relating to attendance, this study investigates the impact of one such overnight environmental science program on students' attendance rate change. Analyzing the secondary data using multiple linear regressions modeling, researchers explored how the overnight environmental program impacted student attendance rate change and how it varied by demographic characteristics to understand if and how the program addresses school district and educational policy reform targets.
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29

Tu, Ting-Chieh, and 杜定傑. "Simulation Analysis and Channel Characteristics for Outdoor Wireless Communications." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/68713868387444434817.

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博士
淡江大學
電機工程學系博士班
97
In this thesis, using different diversity techniques and different simulation environments for outdoor wireless communication systems are presented. However, more obstructions such vehicles, trees, and buildings will degrade the received signal in the outdoor environments. Our purpose is that analyzing and understanding the channel characteristics of outdoor wireless communication. In the Chapter 3, we use the 2.5D SBR-Image ray tracing method to set up the outdoor simulation environment. Moreover, we take account of different types of antenna arrays to evaluate path loss in the outdoor environment. Moreover, by using the genetic algorithm, antenna pattern can be improved to have a good directivity and the reduction of path loss. The Chapter 4 shows different polarization schemes to calculate the cross polarization discrimination (XPD) value in different routes and environments. Polarization diversity is one of the most promising techniques to reduce fading with a compact antenna configuration requiring only one antenna location for the mobile terminal. The applicability of polarization diversity can partly be evaluated to analyze signal cross correlation and cross polarization discrimination (XPD) values. It is helpful to understand what polarization is suitable for the LOS and NLOS routes or urban and semi-urban environments Finally, outdoor channel characteristics with and without traffic in Ultra-wideband system are presented. Most researches of UWB system are concentrated on indoor scenes, but we proposed applications for outdoor UWB systems. By combining with 2.5D SBR/Image method, inverse fast Fourier transform (IFFT) and Hermitian processing, the channel impulse response in the UWB system can be calculated to get the bit error rate. Bit error rate (BER) and outage probability can be used to evaluate the performance of outdoor UWB systems with and without traffic. Based on the large bandwidth of UWB systems, the scale of time resolution on the time domain is just about several nanoseconds. So we take account of the S-rake receiver technique to increase the signal-to-noise ratio (SNR) in order to reduce multipath effect.
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30

Lin, Yu-Tse, and 林佑澤. "Measurements, Simulation and Analysis for Outdoor Wireless Channel Characteristics." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/70187880389518125418.

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碩士
國立臺灣大學
電信工程學研究所
87
This study uses a wideband measurement system to measure radio propagation mechanisms, and we have done two parts of measurements. Part 1, we carry out the measurement in environments with uniform tree clusters and find the effect of the waves penetrating through trees in multipath. With wideband measurements, the direct penetrating wave can be singled out. We can first measure the penetration loss and the electrical length of the direct penetrating path and derive the attenuation constant and the effective dielectric constant from the slopes of the regression lines. In our measurement, the attenuation constants range from 1dB/m to 2dB/m and the effective dielectric constant is very close to 1 no matter how dense the leaves are. Part 2, we measure and simulate different propagation mechanisms respectively, and define the parameters of correlation coefficient and root mean square delay spread to discuss the effect of signal bandwidth on the estimation of radio channel characteristics. We find the larger the distance and the smaller the bandwidth, the smaller the correlation coefficient. In a local area, due to the interference of multipath, the root mean square delay spreads of two close received points drop abruptly even they have a high correlation coefficient. It is also found that the wider the bandwidth, the smaller the standard deviation of the delay spread distribution. Finally, we find that the effect of bandwidth must be considered when proceeding channel simulation.
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31

LIN, HAN-CHANG, and 林翰章. "Wideband measurements and simulation for outdoor radio channel characteristics." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/74406625651559233595.

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碩士
國立臺灣大學
電機工程學系
85
The purpose of this study is to understand the propagation mechanism in complicated outdoor environments. We determine reflection coefficients and diffraction corfficients by using a wide band network analyzer measurementsystem. With this measurement system, we have proved that the average power in space domain equals that in frequency domain by expironment. Significance of this conclusion is that we can use the spectral average to replace the spatial average in the measurement so that the measurement time can be much reduced. Finally, we compare the measured results with those simulated by the 2.5D shooting and bouncing ray-image techniques, where a simplicated layout has been utilized in the simulation.
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32

Ben-Dor, Eshar. "Cellular and peer-to-peer millimeter wave channel sounding in outdoor urban environments." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-12-4766.

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Millimeter wave (mm-Wave) systems have become very attractive recently as lower frequency spectrums used for mobile device communications have been experiencing a “spectral crunch” due to the dissemination of smartphones. Channel characterization of the outdoor urban environment, where networks for mobile devices require the highest data capacity, has been quite scarce and even non-existent for cellular (rooftop to ground) setting measurements. Our project characterizes the urban environment at 38 GHz in a cellular setting and 38 and 60 GHz in a peer-to-peer setting. A sliding correlator channel sounder with an 800 MHz RF bandwidth at 38 GHz and 1.5 GHz RF bandwidth at 60 GHz was constructed to measure the channel using a bandwidth that is larger than the expected bandwidths of future mm-Wave channels. Directional antennas were utilized during the measurements to imitate mm-Wave systems using beam steering antenna arrays, which also allowed for AOA characterization. Path loss and RMS delay spread statistics are provided. Finally, an outage study was performed to test the outage likelihood in an urban environment with many multi-story buildings.
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33

Alsehaili, Mohammad. "Generalized Three Dimensional Geometrical Scattering Channel Model for Indoor and Outdoor Propagation Environments." 2011. http://hdl.handle.net/1993/4384.

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The well known geometrical scattering channel modeling technique has been suggested to describe the spatial statistical distribution of the received multipath signals at various types of wireless communication environments and for different wireless system applications. This technique is based on the assumption that the scatterers, i.e. objects that give rise to the multipath signals, are randomly distributed within a specified geometry that may include the base station and/or the mobile station. The geometrical scattering channel models can provide convenient and simple statistical functions for some of the important physical quantities of the received multipath fading signals, such as: angle of arrival, time of arrival, angular spread, delay spread and the spatial correlation function. In this thesis, a new three dimensional geometrical scattering channel model has been developed for outdoor and indoor wireless communication environments. The probability density functions of the angle of arrival of the received multipath signals are provided in compact forms. These functions facilitate independent control of the angular spread in both the azimuth and the elevation angles via the model's parameters. To establish the model verification, the developed model has been compared against the results from a site-specific propagation prediction technique in indoor and outdoor wireless communication environments. The developed three dimensional model has been extended to include the temporal statistical distribution of the received multipath signals for uniform and non-uniform distributions of the scatterer. Several of the probability density functions of the angle of arrival and time of arrival of the received multipath signals are provided. The probability density functions of the angle of arrival have been validated by comparing them against the results from real channel measurements data. In addition, the developed three dimensional geometrical scattering channel model has been extended for multiple input multiple output wireless channel modeling applications. A three dimensional spatial correlation function has been developed in terms of some of the physical channel's parameters, such as: displacements and orientation of the employed antenna elements. The developed correlation function has been used to simulate and investigate the performance of wireless multiple input multiple output systems in different scenarios.
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34

Lian, Zhen-You, and 連振佑. "Single Outdoor Image Depth Estimation Based on Dark Channel Prior and Color Segmentation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/26001529504456993391.

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碩士
亞洲大學
資訊工程學系碩士班
101
This thesis presents a depth estimation method based on dark channel prior and mean shift algorithms to construct a depth map from a single 2D image of an outdoor scene for 3D display applications. There are three main steps in our method. The first is image segmentation. The intensity of dark channel prior and image color features are used for image segmentation. A series of image processing strategies are applied for dark channel intensity segmentation, e.g. Otsu thresholding, Canny edge detection, etc. The mean shift algorithm is exploited for color feature classification in which U and V channels of YUV color space are used. The second is foreground and background separation. The range of YCbCr and edge density are used to separate foreground and background regions. The third is depth estimation. The depth estimation is calculated separately according to foreground and background regions. In foreground regions, the depth estimation is completed by integration of dark channel and elevation information; while in background regions, the depth estimation is performed by the elevation information only. Experimental results and comparisons show that the proposed method provides good depth estimation and acceptable 3D visual effect.
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35

Tsai, Yi-Shan, and 蔡逸珊. "Data Mining Implement on a Recommendation Mechanism for the Physical and Virtual Channel of Outdoor Appliance." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/56447228284851276942.

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碩士
淡江大學
管理科學學系碩士班
102
Nowadays, people become much busier and start to consider that health is the most important thing in life, so it indirectly increases the scale market of outdoor appliance. However, customers possibly spend more time to select the homogeneous products; so many enterprises start to revise the channel strategy. In regard to this, how to set a nice store Layout in physical channel, improve the right image for brand, and increase competitive advantage are the core issues that worth discussing. This study uses questionnaire survey, and through the ways of data mining: CART, cluster analysis and association rule, to discover how to use the complementarity of the merchandise to design the physical channel, and find out that what product/brand would be the customers buy in different channels and the preference of promotion. According to the above method can tell that which brand and product combination are suit to which promotion and in which channel. Company can use it as the reference of marketing strategy. In the conclusion, the different groups of customers have the different preferences in varied brands and product combination. Company can use different marketing strategies to different groups, it can increase the satisfaction of customers and the business performance.
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36

Ritchie, Genevieve T. "A comparison of human decomposition in an indoor and an outdoor environment." 2005. http://etd.utk.edu/2005/RitchieGenevieve.pdf.

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37

Vanos, Jennifer, Jon Warland, Terry Gillespie, and Natasha Kenny. "Modelling outdoor thermal comfort of humans performing physical activity: applications to health and emergency heat stress preparedness." Thesis, 2011. http://hdl.handle.net/10214/3150.

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Humans are tightly linked to their thermal microclimatic environments, yet few studies have evaluated the outdoor thermal comfort of users performing physical activity. The purpose of this research was to critically review, assess, and apply findings using the COMFA ('COMfort FormulA') human energy budget for users performing physical activity outdoors. Research objectives were: to apply an improved multi-segmented skin temperature approach to the COMFA model; to evaluate its accuracy in predicting actual thermal sensation (ATS); to implement techniques to account for human behaviours associated with clothing and metabolic variations; to spatially assess human energy budget moderating effects of urban parks; and to investigate extreme heat stress situations. To evaluate modelled mean skin temperature (T_sk), field tests were conducted on subjects performing 30 minute outdoor sessions of steady-state moderately intense activity (cycling and running). The model accurately predicted T_sk, showing significantly strong agreement (r = 0.859, p<0.01). ATS votes displayed significantly strong rank correlation with budget scores calculated using both measured and predicted T_sk (r_s = 0.507 and 0.517, respectively, p<0.01). A further improvement of Incorporating conditioning level of an individual gave more realistic estimations of metabolism for budget estimation. Adopting a new relative wind velocity (v_r) equation, which incorporates wind to body angle, revealed errors of the original v_r equation in the modelling of convective heat loss and T_sk. Application of the COMFA model in urban spaces showed that energy budgets were more closely correlated to incoming solar radiation (r = 0.941) than air temperature (r = 0.490), with a significantly strong linear regression found with radiation absorbed by a human (R^2=0.858). Treed greenspace was shown to strongly enhance thermal comfort the greatest, decreasing budgets on average by 25.5 Wm^2. Budget values were found to be a strong predictor of emergency dispatch calls received in Toronto during the July 2010 heat wave (R^2 = 0.86). This study has displayed the potential of the COMFA outdoor model as a new tool to make heat forecasting more meaningful to the public, emergency responders, and urban planners.
OGS; NSERC
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38

Kern, Heidi [Verfasser]. "Nutzen und Chancen des Outdoor-Trainings : eine Methodentriangulation zur Überprüfung des Praxistransfers im betrieblichen Kontext / vorgelegt von Heidi Kern ; Dorothee Schmidt." 2001. http://d-nb.info/969740034/34.

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39

"A Comparison of Los Angeles and Phoenix Homeowners’ Attitudes and Behaviors towards Outdoor Water Conservation." Master's thesis, 2016. http://hdl.handle.net/2286/R.I.40247.

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abstract: Los Angeles, California and Phoenix, Arizona are two naturally water-scarce regions that rely on imported water to meet their local water needs. Both areas have been experiencing an ongoing drought that has negatively affected their local water supply. Populations in both cities continue to grow, increasing overall demand for water as the supply decreases. Water conservation is important for the sustainability of each town. However, the methods utilized to conserve residential water in the two areas differ drastically; Los Angeles has implemented involuntary water rationing and Phoenix has not. The widespread effectiveness of involuntary restrictions makes them a popular management scheme. Despite their immediate effectiveness, little is known about how involuntary restrictions affect attitudinal precursors towards the behavior in question and thus, whether or not the restrictions are potentially helpful or harmful to lasting behavior change. This study adapted the Theory of Planned Behavior to survey 361 homeowners in Los Angeles and Phoenix to examine how involuntary water restrictions shape attitudinal precursors to outdoor water conservation. This study found that when involuntary water restrictions are present, residents feel less in control of their outdoor water use. However, in the presence of involuntary water restrictions, stronger social norms and stronger support for policy prescriptions over outdoor water use were found. The favorable societal support towards water conservation, conceptualized as social norms and policy attitudes, in the presence of involuntary water restrictions is potentially promising for lasting behavior change.
Dissertation/Thesis
Masters Thesis Sustainability 2016
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40

Barriga, Daunas Martha. "Transformative learning and informal environmental education : the case of community gardens." 2004. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=94841&T=F.

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41

Quan, Victoria B. V. "A cohort study of community-dwelling persons following hip fracture : a description of functional changes over 6 months and the predictors of short-term functional mobility and long-term outdoor ambulation." 2005. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=370487&T=F.

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