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Menychtas, Charalampos. "Netted LPI radars." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5601.
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Approved for public release; distribution is unlimited.A significant number of Low Probability of Intercept (LPI) radars are used in various military applications, from guided weapons (such anti-ship missile), to large platforms (aircrafts, ships), to large systems (Integrated Air Defense Systems - IADS). The purpose of this thesis is to evaluate the performance of netted LPI radar systems. To do so, it commences with establishing the theoretical background for the LPI radar techniques and detection methods. Additionally, it presents existing LPI assets along with their operational characteristics to provide the reader with a useful tool for comparative analysis of the LPI radar market. As this work focuses on LPI radar networks, specific emphasis is given to clarifying the notion of a netted system; the conceptual and mathematical background for such are presented in a separate chapter.
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Ong, Peng Ghee Teng Haw Kiad. "Digital LPI radar detector /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA389889.
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Ong, Peng Ghee, and Haw Kiad Teng. "Digital LPI Radar Detector." Thesis, Monterey, California: Naval Postgraduate School, 2001. http://hdl.handle.net/10945/43859.
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Approved for public release; distribution is unlimitedThe function of a Low Probability ofIntercept (LPI) radar is to prevent its interception by an Electronic Support (ES) receiver. This objective is generally achieved through the use of a radar waveform that is mismatched to those waveforms for which an ES receiver is tuned. This allows the radar to achieve a processing gain, with respect to the ES receiver, that is equal to the time-bandwidth product ofthe radar waveform. This processing gain allows the LPI radar to overcome the range-squared advantage ofthe ES receiver in conventional situations. Consequently, a conventional ES receiver can only detect an LPI radar at very short ranges (<3 nm). The focus of this thesis was to develop an ES receiver to detect LPI radar signals with the same sensitivity as conventional pulse signals. It implements a detector which employs a technique, known as "deramping," that forms an adaptive matched filter to the linear FMCW LPI radar signal in order to achieve the processing gain that is equal to the received signal's time-bandwidth product. An experimental transmitter was built to emulate the radar signal with FMCW characteristics and transmitted through a standard gain horn. The transmitted signal is then received via a receiver horn, mixed down to an intermediate frequency (IF), sampled by an A/D convenor and digitally deramped using a Pentium II computer. It was demonstrated that the LPI radar signal can be extracted from the noise background by means of digital deramping
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Lundströmer, Torbjörn. "LPI-radar. Nys eller nytta? : Studie av den militära nyttan med LPI-radar." Thesis, Försvarshögskolan, Militärtekniska avdelningen (MTA), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-975.
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Sedan radar började användas under första hälften av 1900-talet har duellen mellan radar och signalspaning pågått. Genom att utnyttja radar har alltid en medveten risk tagits, risken att bli upptäckt av motståndarens signalspaning. Duellen gavs möjlighet att ta en paus då radarsystem med låg uteffekt introducerades på marknaden under slutet av 1980-talet, nu fanns plötsligt en möjlighet att använda radar samtidigt som de samtida signalspaningssystemen inte kunde upptäcka dessa radarsystem. I föreliggande magisteruppsats i krigsvetenskap med militärteknisk inriktning undersöks räckviddsförhållanden mellan dessa radarsystem och signalspaningssystem. Genom scenarier i den marina arenan försöker jag värdera de taktiska vinster en användare av radar med låg uteffekt kan göra. Analysen visar på att det fram till dess att signalspaningssystem med förmåga att upptäcka radar som utnyttjar låg uteffekt finns tillgängligt är det möjligt att nå taktiska fördelar med dessa system.Since the advent of radar during the early 20th century the duel between radar and electronic support measurement systems has been practised. Using radar has always been associated with a risk of being detected by an opponent’s electronic support measurement systems. The duel came to a halt when radar systems using low output power were introduced on the market during the late 1980s, now it was possible to use radar without being detected by contemporary electronic support measurement systems. The present master of science (one year) thesis in war science with specialization in military technology looks into the range relationships between radar and electronic support measurement systems. Through scenarios in the naval domain, I seek to assess the tactical benefits a user of low probability of intercept radar may have. The analysis indicates that until electronic support measurement systems with the ability to detect radar systems using low output power are available it is still possible to gain tactical advantages with such systems.
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Sjöberg, Andreas. "LPI waveforms for AESA radar." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413598.
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The purpose of low probability of intercept (LPI) radar is, on top of the standard requirements on a radar, to remain undetected by hostile electronic warfare (EW) systems. This can be achieved primarily by reducing the amount of radiated power in any given direction at all times and is done by transmitting longer modulated pulses that can then be compressed digitally in order to retain range resolution. There are multiple different methods of performing pulse compression modifying either the phase or frequency of the transmitted waveform. Another method for attaining LPI properties of a radar is to avoid having a large main lobe in the transmit pattern and instead having lower gain patterns. This then results in a need for post-processing of these patterns by summation of weighted combination of these low gain patterns in order to reform the high gain patterns and thus retain angular resolution. In this work a number of pulse compression waveforms are analysed and compared using their ambiguity properties in order to ascertain which ones can be used in a radar system. They are then used in simulation with GO-CFAR detectors using a variety of analysis tools, specifically the short term Fourier transform (STFT), Wigner-Ville distribution (WVD), quadrature mirror filter bank (QMFB) and spectral correlation density (SCD). Their performance against the detector is based on the rate that the waveforms trigger an alarm and the lower the alarm rate the better the performance. The base reference in terms of performance for these evaluations was set as a triangular FMCW waveform. The results show that the polyphase coded waveforms have good radar and LPI properties in comparison to the FMCW. The frequency hopping codes showed good LPI properties with a large number of frequencies in the sequence but suffer from large ACF side lobes and poor Doppler tolerance. The best LPI results were achieved by a phase coded signal with a random order to its phase terms whilst still maintaining a perfect periodic autocorrelation function (PACF). Potential issues remain with high frequency out of band emission that could lead to a mismatch due to receiver bandpass filtering. The low gain patterns investigated were expanded to include two way patterns for a 2D array and array element tapering. The method works and can be further optimised in order to minimise emissions but adds a significant increase to integration times when the array size grows large.
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Кордяк, Марія Олександрівна, Mariya Kordyak, Дмитрій Олегович Романенко, and Dmytriy Romanenko. "Аналіз логістичної ефективності україни за міжнародним індексом LPI." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/50518.
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1. Фігун Н.В., Білошевська О.Б. Індекс ефективності логістики (LPI) як показник конкурентоспроможності та потенціалу країни. URL: http://surl.li/mqik
2. Молнар О. С., Палійчук Є. С., Ковтюк Ю. І. Методологія визначення логістичної ефективності. URL: http://surl.li/nwwn
3. Юденко А. В. LPI як показник конкурентоспроможності та потенціалу логістичного забезпечення України стосовно країн Європейського Союзу. URL: http://surl.li/nwwlДля оцінки розвитку логістичної системи різних країн і їх порівняння спеціалістами Світового банку був розроблений Індекс ефективності логістики (LPI). Цей показник логістичної ефективності є життєво важливим для торгівлі та економічного зростання національної економіки. Індекс ефективності логістики (Logistics Performance Index, LPI) - це інтерактивний інструмент порівняльного аналізу логістичних профілів країн, який допомагає країнам зіставити виклики та можливості, з якими вони стикаються у сфері торговельної логістики, і визначити шляхи підвищення ефективності у логістичній діяльності. LPI базується на всесвітньому опитуванні операторів на місцях (глобальних експедиторів та експрес-перевізників) та кількісних даних щодо ефективності ключових складових логістичного ланцюга.
To assess the development of the logistics system of different countries and compare them with the World Bank, the Logistics Efficiency Index (LPI) was developed. This indicator of logistics efficiency is vital for trade and economic growth of the national economy. The Logistics Performance Index (LPI) is an interactive tool for comparative analysis of countries' logistics profiles, which helps countries to compare the challenges and opportunities they face in the field of trade logistics and identify ways to increase efficiency in logistics. The LPI is based on a worldwide survey of local operators (global freight forwarders and express carriers) and quantitative data on the efficiency of key components of the logistics chain.
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Denk, Aytug. "Detection and jamming low probability of intercept (LPI) radars." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Sep%5FDenk.pdf.
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Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, September 2006.Thesis Advisor(s): Edward Fisher. "September 2006." Includes bibliographical references (p. 101-104). Also available in print.
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Gulum, Taylan O. "Autonomous non-linear classification of LPI radar signal modulations." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion-image.exe/07Sep%5FGulum.pdf.
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Thesis (M.S. in Electronic Warefare Systems Engineering and M.S. in Electrical Engineering)--Naval Postgraduate School, September 2007.Thesis Advisor(s): Pace, Phillip E. ; Cristi, Roberto. "September 2007." Description based on title screen as viewed on October 23, 2007. Includes bibliographical references (p.189-193). Also available in print.
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Kremzow, Stine. "Einfluss von L-alpha-Lysophosphatidylinositol (LPI) auf neuronale Schädigungsprozesse." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-180768.
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Die vorliegende Arbeit beinhaltet experimentelle Untersuchungen zur neuroprotektiven
Wirkung des körpereigenen Lipids L-alpha-Lysophosphatidylinositol (LPI). Die Vermittlung
dieser Wirkung soll durch den zentralnervös exprimierten G-Protein-gekoppelten Rezeptor 55
(GPR55) erfolgen. Als Modelsystem diente die organotypische hippocampale Schnittkultur
(OHSC) der Ratte, welche exzitotoxisch mittels N-Methyl-D-Aspartat (NMDA) geschädigt
wurde, um Neurodegeneration zu initiieren. Die Inkubation mit LPI nach NMDA-Schädigung
reduzierte die Anzahl toter Neurone und die der Mikroglia in der Körnerzellschicht des Gyrus
dentatus. Ein Clodronat-induzierter Verlust der Mikroglia und die siRNA-vermittelte
Herabregulation von Gpr55 hoben jeweils den neuroprotektiven Effekt von LPI in der OHSC
auf. Diese Beobachtungen wiesen auf eine Mikroglia- und GPR55 abhängige Neuroprotektion
hin. LPI wirkte zudem synergistisch und verstärkte die (bekannter Maßen) durch
Cannabinoide induzierte und über den Cannabinoid Typ 1 Rezeptor vermittelte
Neuroprotektion. Ferner wurde Gpr55 mittels qPCR in Mikroglia und Astrozyten
nachgewiesen. LPI steuerte außerdem die Expression von Gpr55 in Mikroglia und
beeinflusste deren Migrationsverhalten. Die vorliegenden Ergebnisse machen deutlich, dass
LPI in einem in vitro Modellsystem zur Untersuchung des sekundären neuronalen Schadens
protektiv wirkt und für die Vermittlung dieser Neuroprotektion Mikroglia und GPR55 in
Frage kommen.
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Kassab, Rami. "OPTIMISATION ET CONCEPTION DE FORMES D'ONDE LPI POUR RADAR MONOSTATIQUE." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00449768.
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L'un des traits les plus importants du radar moderne est la faible probabilité d'interception. Afin de garantir cette propriété, le radar doit étaler le plus possible son énergie en temps et en fréquence. Cependant, pour une configuration monostatique où la voie de réception est coupée pendant l'émission, l'étalement de l'énergie dans le temps entraîne une augmentation des pertes d'éclipses dégradant les performances radar pour les distances en question. D'autre part, la bande disponible est limitée, contrainte par des restrictions et parfois partagée avec d'autres applications. Ainsi, dans cette étude, la stratégie de transmission-réception est dans un premier temps optimisée afin de gérer les pertes d'éclipse et atteindre un bon rapport cyclique. Ensuite, une nouvelle technique simple et efficace est proposée permettant au radar d'adapter rapidement ses transmissions à un environnement spectral congestionné. Finalement, les formes d'onde résultantes ainsi que la technique de codage ont été testées en pratique dans le cadre de détection et de localisation d'avions en bande HF.
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Kellett, Daniel. "Random Sequence Encoding with OFDM for Covert Communication and Signal Reuse for LPI/LPD Radar: Theory & Experiments." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1501120348908255.
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Taccioli, Leonardo. "Sistemi innovativi per l'alimentazione di GPL in motori ad accensione comandata." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12900/.
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Negli ultimi anni il GPL si è sempre più imposto come carburante alternativo per l’autotrazione, soprattutto in campo automobilistico, a causa di vantaggi principalmente economici ed ecologici. I sistemi tradizionali di iniezione di tale combustibile risultano però avere problemi tecnici principalmente legati alla natura gassosa con la quale il GPL viene iniettato. Per questo si sono sviluppati negli ultimi anni nuovi sistemi che prevedono l’iniezione liquida del GPL che tende a risolvere proprio queste problematiche. Nello svolgimento del seguente lavoro di tesi, ho per prima cosa analizzato il carburante GPL, enunciandone la composizione, le proprietà chimiche e fisiche da cui derivano le motivazioni del suo utilizzo nell’automotive e i vantaggi e gli svantaggi rispetto ad altri combustibili più comuni. Dopo aver brevemente parlato della storia del suo utilizzo, concentrandomi su quello automobilistico, ho descritto i vari componenti e il funzionamento dei tradizionali e più comuni sistemi benzina-GPL (iniettato allo stato gassoso), diesel-GPL (meno comuni e sui quali si sta ancora facendo innovazione) e infine le ultime tecnologie, i sistemi che prevedono l’iniezione liquida del GPL, che si dividono in sistemi ad iniezione indiretta (LPi) e diretta (LPdi), questi ultimi più recenti di una decina d’anni rispetto ai precedenti LPi. Ho concentrato la maggior parte della mia attenzione nel descrivere i vari vantaggi (e pure svantaggi) di questi nuovi sistemi di iniezione, confrontandoli con l’iniezione gassosa del GPL e con l’utilizzo al posto della benzina.
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Belcher, Robert W. "Extremely High Frequency (EHF) Low Probability of Intercept (LPI) communication applications." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA226653.
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Thesis (M.S. in Telecommunications Systems Management)--Naval Postgraduate School, March 1990.Thesis Advisor(s): Schwendtner, Thomas A. Second Reader: Davidson, K. L. "March 1990." Description based on title screen as viewed on August 25, 2009. DTIC Descriptor(s): Interception probabilities, communication and radio systems, communications networks, spectra, command and control systems, extremely high frequency, naval operations, tactical warfare, low rate, theses, scenarios, line of sight, military applications. Author(s) subject terms: Millimeter wave, EHF, Extremely High Frequency, LPI, Low Probability of Intercept. Includes bibliographical references (p. 68-70). Also available print.
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Grancharova, Mila. "Representation Learning for Modulation Recognition of LPI Radar Signals Through Clustering." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-283194.
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Today, there is a demand for reliable ways to perform automatic modulation recognition of Low Probability of Intercept (LPI) radar signals, not least in the defense industry. This study explores the possibility of performing automatic modulation recognition on these signals through clustering and more specifically how to learn representations of input signals for this task. A semi-supervised approach using a bootstrapped convolutional neural network classifier for representation learning is proposed. A comparison is made between training the representation learner on raw time-series and on spectral representations of the input signals. It is concluded that, overall, the system trained on spectral representations performs better, though both approaches show promise and should be explored further. The proposed system is tested both on known modulation types and on previously unseen modulation types in the task of novelty detection. The results show that the system can successfully identify known modulation types with adjusted mutual information of 0.86 for signal-to-noise ratios ranging from -10 dB to 10 dB. When introducing previously unseen modulations, up to six modulations can be identified with adjusted mutual information above 0.85. Furthermore, it is shown that the system can learn to separate LPI radar signals from telecom signals which are present in most signal environments.Idag finns ett behov av pålitlig automatiserad modulationsigenkänning (AMR) av Low Probability of Inercept (LPI)-radarsignaler, inte minst hos försvarsindustrin. Denna studie utforskar möjligheten att utföra AMR av dessa signaler genom klustring och mer specifikt hur man bör lära in representationer av signalerna i detta syfte. En halvövervakad inlärningsmetod som använder en klassificerare baserad på faltningsnätverk föreslås. En jämförelse görs mellan ett system som tränar för representationsinlärning på råa tidsserier och ett system som tränar på spektrala representationer av signalerna. Resultaten visar att systemet tränat på spektrala representationer på det stora hela presterar bättre, men båda metoderna visar lovande resultat och bör utforskas vidare. Systemet testas på signaler från både kända och för systemet tidigare okända modulationer i syfte att pröva förmågan att upptäcka nya typer av modulationer. Systemet identifierar kända modulationer med adjusted mutual information på 0.86 i brusnivåer från -10 dB till 10 dB. När tidigare okända modulationer introduceras till systemet ligger adjusted mutual information över 0.85 för upp till sex modulationer. Studien visar dessutom att systemet kan lära sig skilja LPI-radarsignaler från telekommunikationssignaler som är vanliga i de flesta signalmiljöer.
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Kremzow, Stine [Verfasser], Marco [Akademischer Betreuer] Koch, Michael [Gutachter] Schaefer, and Thomas [Gutachter] Arendt. "Einfluss von L-alpha-Lysophosphatidylinositol (LPI) auf neuronale Schädigungsprozesse : Einfluss von L-alpha-Lysophosphatidylinositol (LPI) aufneuronale Schädigungsprozesse / Stine Kremzow ; Gutachter: Michael Schaefer, Thomas Arendt ; Betreuer: Marco Koch." Leipzig : Universitätsbibliothek Leipzig, 2016. http://d-nb.info/1239658540/34.
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Lima, Antonio F. "Analysis of low probability of intercept (LPI) radar signals using cyclostationary processing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FLima.pdf.
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Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, September 2002.Thesis advisor(s): Phillip E. Pace, Herschel H. Loomis. Includes bibliographical references (p. 159-160). Also available online.
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Norén, Gustav. "Noise Robustness of Convolutional Autoencoders and Neural Networks for LPI Radar Classification." Thesis, KTH, Matematisk statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-273604.
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This study evaluates noise robustness of convolutional autoencoders and neural networks for classification of Low Probability of Intercept (LPI) radar modulation type. Specifically, a number of different neural network architectures are tested in four different synthetic noise environments. Tests in Gaussian noise show that performance is decreasing with decreasing Signal to Noise Ratio (SNR). Training a network on all SNRs in the dataset achieved a peak performance of 70.8 % at SNR=-6 dB with a denoising autoencoder and convolutional classifier setup. Tests indicate that the models have a difficult time generalizing to SNRs lower than what is provided in training data, performing roughly 10-20% worse than when those SNRs are included in the training data. If intermediate SNRs are removed from the training data the models can generalize and perform similarly to tests where, intermediate noise levels are included in the training data. When testing data is generated with different parameters to training data performance is underwhelming, with a peak performance of 22.0 % at SNR=-6 dB. The last tests done use telecom signals as additive noise instead of Gaussian noise. These tests are performed when the LPI and telecom signals appear at different frequencies. The models preform well on such cases with a peak performance of 80.3 % at an intermidiate noise level. This study also contribute with a different, and more realistic, way of generating data than what is prevalent in literature as well as a network that performs well without the need for signal preprocessing. Without preprocessing a peak performance of 64.9 % was achieved at SNR=-6 dB. It is customary to generate data such that each sample always includes the start of its signals period which increases performance by around 20 % across all tests. In a real application however it is not certain that the start of a received signal can be determined.Detta arbete studerar brustålighet hos neurala nätverk för klassificering av \textit{låg sannolikhet för avlyssning} (LPI) radars modulationstyp. Specifikt testas ett antal arkitekturer baserade på faltningsnätverk och evalueras i fyra olika syntetiska brusmiljöer. Tester genomförda på data med Gaussiskt brus visar att klasificeringsfelet är ökande med ett minskande signal-till-brusförhållande. Om man låter nätverken träna på alla brusnivåer som ingår i datan uppnås en högsta pricksäkerhet om 70.8 % vid ett signal-till-brusförhållande på -6 dB. Vidare tester tyder på att nätverken presterar sämre på låga signal-till-brusförhållanden om de inte finns med i träningsdata och ger i allmänhet mellan 10-20 % sämre pricksäkerhet. Om de mellersta brusnivåerna inte finns med i träningsdata presterar nätverken lika bra som när de finns med i träningsdata. Om träningsdata och testdata genereras med olika parameterar presterar nätverken dåligt. För dessa tester uppnås en högsta pricksäkerhet om 22.0 % vid ett signal-till-brusförhållande på -6 dB. Den sista brusmiljön som testades på använder sig av telekom signaler som om de vore brus istället för Gaussiskt brus. I detta fall är LPI och telekom signalerna väl skiljda i frekvens och nätverken presterar lika bra som tester i Gaussiskt brus med högt signal-till-brusförhållande. Högsta pricksäkerhet som uppnåts på dessa tester är 80.3 % i mellanhög brusnivå. Detta arbete bidrar även med nätverk som presterar bra utan att data behöver signalbehandlas innnan den kan klassificeras samt genererar data på ett mer realistiskt vis än tidigare litteratur inom detta område. Utan att signalbehandla data uppnåddes en högsta pricksäkerhet om 64.9 % vid ett signal-till-brusförhållande på -6 dB. Den mer realistiska datan genereras så att dess startpunkt är slumpmässig. I litteraturen brukar startpunkten inkluderas och uppnår på så vis överlag pricksäkerheter som är ungefär 20 % högre än de tester som genomförs i detta arbete. I verkliga applikationer är det sällan man kan identifera en signals startpunkt med säkerhet.
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Brown, Dane A. "ELINT signal processing on reconfigurable computers for detection and classification of LPI Emitters." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FBrown.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2006.Thesis Advisor(s): Douglas J. Fouts. "June 2006." Includes bibliographical references (p. 83). Also available in print.
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Gau, Jen-Yu. "Analysis of low probability of intercept (LPI) radar signals using the Wigner Distribution." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FGau.pdf.
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Thesis (M.S. in Systems Engineering)--Naval Postgraduate School, September 2002.Thesis advisor(s): Phillip E. Pace, Herschel H. Loomis, Jr. Includes bibliographical references (p. 145-146). Also available online.
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Zilberman, Eric R. "Autonomous time-frequency cropping and feature-extraction algorithms for classification of LPI radar modulations." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FZilberman.pdf.
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Upperman, Teresa Lynn Odom. "ELINT signal processing on reconfigureable [sic] reconfigurable computers for detection and classification of LPI emitters." Monterey, Calif. : Naval Postgraduate School, 2008. http://bosun.nps.edu/uhtbin/hyperion-image.exe/08Mar%5FUpperman%5FTeresa.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, March 2008.Thesis Advisor(s): Fouts, Douglas J. ; Pace, Phillip E. "March 2008." Description based on title screen as viewed on May 16, 2008. Includes bibliographical references (p. 81-82). Also available in print.
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Upperman, Teresa Lynn Odom. "ELINT signal processing using Choi-Williams distribution on reconfigurable computers for detection and classification of LPI emitters." Thesis, Monterey California. Naval Postgraduate School, 2008. http://hdl.handle.net/10945/4156.
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This thesis documents the use of the SRC-6 Reconfigurable Computer for use in analyzing low probability of intercept (LPI) signals using the Choi-Williams distribution. The SRC-6 is a reconfigurable computer manufactured by SRC Computers, Inc. which allows the user to tailor both the software and the hardware to a specific task. This increases the speed at which the task can be accomplished making it useful for applications in electronic intelligence (ELINT). The Choi-Williams distribution is a mathematical technique that was first created using MATLAB and then converted to C code for use on the SRC-6. The purpose of this study is to investigate the feasibility of using a reconfigurable computer for ELINT applications and the timely detection and classification of LPI signals. This thesis is part of a larger study to use reconfigurable computers for the autonomous detection and classification of LPI signals.
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Haisan, Abdulqader Mohamed Saeed. "Direct Sequence Spread Spectrum (DS/SS) chip coding techniques for enhancing low-probalility of intercept (LPI) performance." Thesis, Cranfield University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238876.
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Hair, Steven C. "Determining the role of the LPI/GPR55 system in the development of obesity and associated cardiovascular consequences." Thesis, Robert Gordon University, 2018. http://hdl.handle.net/10059/3115.
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Obesity has reached worldwide epidemic proportions and with this increased incidence of obesity, comes an increase in incidence of the comorbidities associated with obesity such as diabetes and cardiovascular disease (CVD). The underlying mechanisms which connect these diseases are still poorly understood. One system which has been shown to be up-regulated in the setting of obesity and diabetes is that of the G-protein coupled receptor-55/Lysophosphatidylinositol (GPR55/LPI). Despite being upregulated in the setting of obesity, the function of GPR55 in obesity and other disease states remains elusive. Therefore, the present study aimed to 1) investigate the role of GPR55 in obesity by characterising the phenotype of the GPR55 knockout (GPR55-/-) mouse when challenged with a high fat diet (HFD) intervention, 2) elucidate any effect of the GPR55 knockout and HFD intervention on the myocardial infarct size sustained following a period of ischaemia/reperfusion (I/R) and 3) make use of an in vitro model to elucidate the mechanisms by which changes occur in the adipose tissue of mice fed a HFD. GPR55-/- mice fed a HFD for 12-weeks gained significantly more weight in the form of fat mass, compared to wild-type (WT) controls and consequently become obese. Obese GPR55-/- mice displayed hypertrophic adipose tissue concurrent with the significant dysregulation of plasma lipids, increases in specific circulating LPI species, increased lipid deposition within the liver and a change in adipose tissue gene expression profile. These changes were not observed in GPR55-/- mice fed a standard diet or WT mice fed a HFD. Following a period of I/R, the myocardial infarct size in hearts from WT HFD fed mice was significantly smaller than in hearts from WT standard diet fed mice. This reduction in infarct size due to HFD intervention was not dependent on RISK-pathway activation and was not observed in hearts from GPR55-/- mice, therefore demonstrating that the cardio-protective effect of a HFD on infarct size is dependent on GPR55. In vitro studies using 3T3-L1 cells determined that the changes in adipose tissue gene expression of HFD fed mice was not due to enhanced stimulation with LPI or via hypoxic mechanisms. The results of these studies demonstrate that GPR55 has an anti-obesity function in vivo and also mediates the cardio-protective effect of a HFD on myocardial infarct size, through currently unknown mechanisms.
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Ekelund, Måns. "Uncertainty Estimation for Deep Learning-based LPI Radar Classification : A Comparative Study of Bayesian Neural Networks and Deep Ensembles." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-301653.
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Deep Neural Networks (DNNs) have shown promising results in classifying known Low-probability-of-intercept (LPI) radar signals in noisy environments. However, regular DNNs produce low-quality confidence and uncertainty estimates, making them unreliable, which inhibit deployment in real-world settings. Hence, the need for robust uncertainty estimation methods has grown, and two categories emerged, Bayesian approximation and ensemble learning. As autonomous LPI radar classification is deployed in safety-critical environments, this study compares Bayesian Neural Networks (BNNs) and Deep Ensembles (DEs) as uncertainty estimation methods. We synthetically generate a training and test data set, as well as a shifted data set where subtle changes are made to the signal parameters. The methods are evaluated on predictive performance, relevant confidence and uncertainty estimation metrics, and method-related metrics such as model size, training, and inference time. Our results show that our DE achieves slightly higher predictive performance than the BNN on both in-distribution and shifted data with an accuracy of 74% and 32%, respectively. Further, we show that both methods exhibit more cautiousness in their predictions compared to a regular DNN for in-distribution data, while the confidence quality significantly degrades on shifted data. Uncertainty in predictions is evaluated as predictive entropy, and we show that both methods exhibit higher uncertainty on shifted data. We also show that the signal-to-noise ratio affects uncertainty compared to a regular DNN. However, none of the methods exhibit uncertainty when making predictions on unseen signal modulation patterns, which is not a desirable behavior. Further, we conclude that the amount of available resources could influence the choice of the method since DEs are resource-heavy, requiring more memory than a regular DNN or BNN. On the other hand, the BNN requires a far longer training time.Tidigare studier har visat att djupa neurala nätverk (DNN) kan klassificera signalmönster för en speciell typ av radar (LPI) som är skapad för att vara svår att identifiera och avlyssna. Traditionella neurala nätverk saknar dock ett naturligt sätt att skatta osäkerhet, vilket skadar deras pålitlighet och förhindrar att de används i säkerhetskritiska miljöer. Osäkerhetsskattning för djupinlärning har därför vuxit och på senare tid blivit ett stort område med två tydliga kategorier, Bayesiansk approximering och ensemblemetoder. LPI radarklassificering är av stort intresse för försvarsindustrin, och tekniken kommer med största sannolikhet att appliceras i säkerhetskritiska miljöer. I denna studie jämför vi Bayesianska neurala nätverk och djupa ensembler för LPI radarklassificering. Resultaten från studien pekar på att en djup ensemble uppnår högre träffsäkerhet än ett Bayesianskt neuralt nätverk och att båda metoderna uppvisar återhållsamhet i sina förutsägelser jämfört med ett traditionellt djupt neuralt nätverk. Vi skattar osäkerhet som entropi och visar att osäkerheten i metodernas slutledningar ökar både på höga brusnivåer och på data som är något förskjuten från den kända datadistributionen. Resultaten visar dock att metodernas osäkerhet inte ökar jämfört med ett vanligt nätverk när de får se tidigare osedda signal mönster. Vi visar också att val av metod kan influeras av tillgängliga resurser, eftersom djupa ensembler kräver mycket minne jämfört med ett traditionellt eller Bayesianskt neuralt nätverk.
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Scribner, Leroy A. "A Comparison of Ohio University’s College Student Personnel Classes Using Kouzes and Posner’s Leadership Practices Inventory." Ohio University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1113834207.
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Hurst, Katrina M. "Modulation of Synaptic Plasticity: Endocannabinoids and Novel G-protein Coupled Receptors Expression and Translational Effects in Interneurons." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6940.
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Learning and memory are important processes that occur in the brain. The brain is comprised of neurons that make connections with each other known as synapses. Synaptic plasticity is widely believed to be the physiologic mechanism by which learning and memory occur. Synapses can either be strengthened through a process known as long-term potentiation (LTP) or weakened through long-term depression (LTD). The area of the brain that is most studied for its role in learning and memory is the hippocampus, which has been shown to be involved in memory consolidation. The detection of endocannabinoids and their receptors has opened a whole new field of study in regards to synaptic plasticity. Cannabinoid receptor 1 (CB1) and transient receptor potential vanilloid 1 (TRPV1) are among the commonly studied endocannabinoid receptors found in the central nervous system. In the brain, these receptors' natural ligands, anandamide and 2-arachidonylglycerol (2-AG), are found in abundance. Yet not all forms of observed plasticity are accounted for by just these two receptors, so studies into other G-protein coupled receptors (GPCRs) continues. One GPCR, GPR55 is found in many regions of the brain, as well as lysophosphatidylinositol (LPI), its specific ligand. Here we have researched the role of GPR55 in modulating synaptic plasticity in the hippocampus. Using quantitative reverse transcription PCR and immunohistochemistry, we have found GPR55 to be expressed in the hippocampus with highest expression in pyramidal cells, the main excitatory neurons in the hippocampus. Using field and whole cell electrophysiology, we have investigated its effects on synaptic plasticity, discovering that activation of GPR55 by LPI significantly enhances LTP. In memory behavioral assays there are no significant differences between GPR55 KO mice and wild type littermates, indicating that it may not be involved in endogenous memory processes. However, our electrophysiology data makes GPR55 a potential target for treating memory disorders such as dementia. We have also investigated GPR18 and GPR119 for their potential roles in synaptic plasticity. First, we confirmed their expression in the hippocampus and then investigated the effects of their agonists on plasticity. Another receptor, TRPV1 has been studied to alter plasticity. However, the study of how protein translation and RNA transcription involvement in TRPV1 plasticity in mammals has not been investigated. While translation and transcription are known to be important in many forms of LTP, it is unknown whether these processes are important for TRPV1-induced LTD. We are investigating their necessity via whole cell patching and using translation and transcription inhibitors Anisomycin and Actinomycin D, both previously used in slice electrophysiology.
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Qualls, Isaiah Christopher. "OPTIMIZATION OF DUAL-USE RADARCOM SIGNALS AND AN ANALYSIS OF INTERCEPTOR PENALIZATION." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1565109330281541.
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Voignier, Arnaud. "L’artère comme un milieu à microdilatation : une investigation numérique." Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0233.
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Les artères, comme les tissus biologiques mous en général, possèdent une structure interne et une organisation complexe sur des échelles difficilement différenciables. Certains phénomènes viennent altérer cette microstructure induisant ainsi une modification de leur réponse au même niveau de stimuli et donc de leur comportement macroscopique. On peut citer l’artériosclérose qui est un processus naturel qui se caractérise par un épaississement et une moins bonne déformabilité de la paroi artérielle. On dit alors que la paroi artérielle s’est rigidifiée. Celle-ci est due en partie au remodelage correspondant à une modification de structure intervenant par synthèse de nouveaux constituants avec une organisation différente ou par réorganisation de ceux qui sont existants. On peut aussi mentionner l’athérosclérose, une pathologie se traduisant par l’accumulation de lipides, glucides, tissus adipeux, etc. créant une plaque appelée athérome au niveau de la paroi interne de l’artère. Celle-ci vient accélérer l’artériosclérose et par suite modifier la microstructure par remodelage. L’optimisation des techniques thérapeutiques appliquées à certaines maladies du système artériel nécessite l’analyse de l’artère considérée comme un système mécanique. De ce fait, la modélisation mathématique de son comportement mécanique est impérative. Compte tenu de la complexité de sa microstructure, nous avons opté pour une représentation de son comportement dans le cadre des milieux micromorphiques de Eringen et plus particulièrement dans le cadre des milieux à microdilatation. On conçoit aisément que l’artère est sollicitée en régime de fonctionnement normal dans le domaine de petites déformations élastiques. La solution des équations de champ permettant d’analyser l’état de contrainte et de déformation induit par un stimulus extérieur ne peut en général être obtenue que numériquement. Du fait de la complexité du modèle de comportement, nous avons dû développer un outil numérique spécifiquement dédié. Cet outil est basé sur un couplage astucieux de la méthode des éléments de frontières et d’une méthode sans maillage de collocation par points. Cet outil numérique a été validé sur un nombre de cas simples permettant une comparaison des solutions numériques et analytiques. L’analyse de l’artère comme un milieu à microdilatation homogène est entrepris dans un premier temps. Puis, motivée par l’observation de la structure en couches de l’artère dont les propriétés mécaniques sont différentes, l’analyse se poursuit en considérant le milieu comme non homogène. Le travail a ensuite été étendu à l’étude de l’artériosclérose en simulant en premier lieu la modification de la déformabilité par une modification des caractéristiques microstructurales puis par l’insertion d’inclusions inertes. Une étude approfondie sur l’impact que peuvent avoir de telles zones en fonction de leur taille et leur position dans la paroi artérielle est menée. Enfin, l’athérosclérose et l’angioplastie sont abordées par la prise en compte d’une plaque d’athérome rigide. Les résultats obtenus ont déjà permis d’éclairer certaines observations cliniques. On peut en particulier mentionner le processus de remodelage induit par la dégénérescence locale des propriétés mécaniques de l’artère ainsi que par la pose d’un stent dont l’utilité clinique n’est plus à démontrer. Ce travail devrait être poursuivi par l’identification effective des paramètres microstructuraux et par l’optimisation des propriétés mécaniques de stents pour une localisation de la zone de remodelage. Il sera aussi nécessaire de prendre en compte l’anisotropie de l’artèreArteries, like soft biological tissues in general, have an internal structure and a complex organization on several scales. Some phenomena alter this microstructure inducing a modification of their response at the same level of stimuli and therefore their macroscopic behavior. Among these phenomena, there may be mentioned arteriosclerosis, a natural process which is characterized by thickening and lowest deformability of the arterial wall. The arterial wall has stiffened. This stiffening is due in part to the remodeling corresponding to a modification of structure involving synthesis of new constituents with a different organization or reorganization of existing ones. We can also mention atherosclerosis, a pathology resulting in accumulation of lipids, carbohydrates, adipose tissue, etc. creating a plaque called atheroma at the inner wall of the artery. This pathology accelerates arteriosclerosis and subsequently modifies the microstructure by remodeling. The optimization of therapeutic techniques applied to the diseases of the arterial system requires the analysis of the artery considered as a mechanical system. Thus, mathematical modelling of its mechanical behavior is imperative. Given the complexity of its microstructure, we opted for a representation of its behavior in the context of Eringen micromorphic media and more particularly in the context of microdilatation media.The artery, in normal operating conditions, is subjected to small elastic deformations. The solution of field equations for analysing the state of stress and deformation induced by an external stimulus can generally be obtained only numerically. Due to the complexity of the behaviour model, we had to develop a dedicated tool. It is based on a clever coupling of the boundary element method and a collocation point method. The digital tool developed has been validated on a number of simple cases allowing a comparison of numerical and analytical solutions. The analysis of the artery as a homogeneous microdilatation medium is undertaken initially. Then, motivated by the observation of the layered structure of the artery with different mechanical properties, the analysis continues by considering the medium as non-homogeneous. The work was then extended to the study of arteriosclerosis by first simulating the modification of the deformability by a modification of the microstructural characteristics then by the insertion of inert inclusions. An in-depth study of the impact of such areas with different size and position in the arterial wall is conducted. Finally, atherosclerosis and angioplasty are approached by considering a rigid atheroma plaque. The results obtained highlight some clinical observations. In particular, we can mention the remodelling process induced by the local degeneration of the mechanical properties of the artery or by the stent placement whose clinical utility is no longer to be demonstrated. This work should be continued by the effective identification of the microstructural parameters of the artery and by the optimization of the mechanical properties of stents to localize the remodeling area. It will also be necessary to take into account the global anisotropy of the artery
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Badgley, Corinne Marie. "The Putative Cannabinoid Receptor GPR55 Modulates Synaptic Plasticity in the Hippocampus." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3585.
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Endocannabinoids (eCBs) are small molecules that are capable of modulating synaptic plasticity of both excitatory and inhibitory synapses in the brain. While eCBs bind to transient receptor potential vanilloid 1 (TRPV1) and cannabinoid receptor 1 (CB1) in the central nervous system, we recently identified a form of non-CB1, non-TRPV1 mediated long term depression activated by the eCB anandamide at CA1 hippocampal stratum radiatum interneurons. GPR55, an orphan G-protein receptor, has been identified in the hippocampus and is capable of activation by eCBs, making it a good candidate for mediating this non-CB1, non-TRPV1 form of synaptic plasticity. Here we performed whole-cell patch clamp recordings from CA1 stratum radiatum interneurons in rat brain slices to investigate the effect of GPR55 agonist O-1602 on excitatory synapses. We also performed field recordings from CA1 pyramidal cells in rats and GPR55 knockout mice and littermate controls to investigate the effect of GPR55 agonists O-1602 and lysophosphatidylinositol (LPI) on both basal output and electrically induced long-term depression and long-term potentiation in the hippocampus. Application of O-1602 in rats depressed long-term potentiation in CA1 pyramidal cells, and depressed excitatory glutamatergic transmission onto some interneurons. O-1602 had no effect on long-term depression of CA1 pyramidal cells. GPR55 +/+ mice showed an increase in long-term potentiation in the presence of LPI compared to GPR55-/- littermates. GPR55-/-mice had no change in long-term potentiation when exposed to O-1602, though there was an increase in post-tetanic potentiation with O-1602. In order to examine whether GPR55 has a role in formation of spatial memory, GPR55 -/- mice were compared to littermate controls during a Morris water maze behavioral task, with a reversal task after 7 days of training. GPR55-/-mice did not perform in a different manner on either the training task or the reversal, though there may be a trend of difference in training worth investigating further. This study illustrates a novel pathway for synaptic plasticity modulation through GPR55 in the hippocampus, and may therefore provide valuable insight into both the effects of synthetic and endogenous cannabinoids on the brain and the processes underlying learning and memory.
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Ling, Rebecca. "Construction of a fusion protein for anchoring the inflammatory receptor NLRP3 to the cell membrane." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17482.
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The innate immune system are a cooperation of many components – receptors being one of them. Both membrane-bound and cytosolic receptors play a large role in the defence system against pathogens and danger. NLRP3 is a receptor which assembles a protein complex called inflammasome in response to cytosolic stress and is responsible for many autoimmune diseases if it malfunctions. The activation of the NLRP3 inflammasome leads to secretion of inflammatory cytokines and in many cases to programmed cell death. The structure, function and activation of the NLRP3 inflammasome is still not fully understood and the urge to understand the mechanisms behind are important for future medical improvements. The aim was to anchor the NLRP3 inflammasome by the cell membrane - By Overlap PCR, the NLRP3 cDNA was fused extracellular and trans-membrane parts of the TLR4 cDNA to anchor the NLRP3 to the membrane and in turn analyse the inflammasome with LPI™ technology. Multiple primers and a TLR4 nucleotide were designed and the NLRP3 was amplified with specific overhangs by PCR. The fusion protein was successfully linked together by Overlap PCR but not confirmed by sequencing. The gene fusion demands high quality primers for amplification and further evaluation must be made to the details of the laboratory. To anchor the protein complex to the cell membrane, continue to be of full importance and can be an asset in many structural studies and biopharmaceuticals trials.
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Sullivan, Patricia Sullivan. "The Relationship of Self-Awareness to Leadership Effectiveness for Experienced Leaders." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6764.
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The purpose of this research was to investigate the relationship between leaders’ self-awareness and their effectiveness. The population included leaders with at least five years of experience in a leadership role. Participants were recruited by snowball sampling methods; the researcher used a diverse network of professionals to recruit other leaders from diverse industries. Each leader completed a 35-survey questionnaire along with demographic questions (gender, education, years in leadership role, industry), and was required to ask at least four direct reports to complete the 35 questions about observed behaviors of their leader. After removing incomplete responses, the final sample included N = 179 leaders, each with at least four direct reports (N = 761).
Data were collected using three well-established, validated research instruments for this quantitative correlational study: the Emotional and Social Competency Inventory (ESCI) (Boyatzis, 2007), the Leadership Practices Inventory SELF (LPI-SELF) (Kouzes & Posner, 2013b) and the Leadership Practices Inventory OBSERVER (LPI-OBSERVER) (Kouzes & Posner, 2013a). LPI surveys provided five independent leadership competency scores: Modeling the Way, Inspiring a Shared Vision, Challenging the Process, Enabling Others to Act, and Encouraging the Heart (Kouzes & Posner, 2012). Qualtrics, an approved third-party online survey platform, was used to collect and analyze study questions.
The study measured direction and strength of leaders’ LPI scores and self-awareness, the direction and strength of how the direct reports’ rated their leaders’ LPI practices and the leaders’ self-awareness; it also measured if there were significant differences in how the leaders rated themselves based on gender, education and time in a leadership position.
The results indicated a positive, but not strong relationship between leaders’ own LPI scores and self-awareness. The relationship of the direct reports’ observation of leaders and their self-awareness appeared positive and strong for each of the five competencies.
The correlation of the five LPI-SELF competencies and self-awareness to gender did not appear significantly different. Results appeared different in four of the five leadership practices based on education. Only Challenging the Process was similar for all educational levels. Whereas, years as a leader appear similar in four of the five leadership practices, and only Modeling the Way showed different results.
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Wicker, Teri. "Self-Report of Nursing Leadership Practice After Completion of Training." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195154.
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The purpose of this research project was to examine whether frontline nurse managers who had attended a leadership program, perceived their leadership style as containing behaviors representative of transformational leadership. A secondary purpose was to determine the participant's opinions about the value of a leadership program for their practice. Current literature was utilized to support this research project examining a nursing systems issue.The primary instrument used to collect data about leader practice was the Leadership Practices Inventory (LPI) (University of Georgia, 2002). An evaluation tool was also designed and utilized to gather information about the participant's perception of their leadership behaviors after completion of a training program. Survey participants were selected from nurses who completed the Arizona Healthcare Leadership Academy (AzHCLA) (2007) course in the last four years.A course survey and results from the LPI revealed that study participants perceived an increase in their behaviors related to leading others as well as having learned new skills by having completed the AzHCLA course. Nurse's educational levels were compared to the five leadership practice subgroups from the LPI to examine whether a nurse's educational level could better account for an increase in leadership competencies. Research data revealed that no relationship between educational levels existed but that certain leadership skills were gained by having completed a leadership educational program. By using descriptive statistics, mean scores were used to identify differences in how nurses perceived their individual competencies and behaviors after having completed leadership education. Reported perceptions of competencies and behaviors indicated that educational programs can be beneficial to frontline nurse leaders.While results from an ANOVA showed there was no statistical significance related to education and LPI subgroups, there was a trend in the mean differences for those individuals with a master's degree. Qualitative data revealed that course participants perceived having gained new leadership skills and behaviors. The data from this study created a baseline of information that warrants further investigation to identify if indeed education makes a difference in perceived leadership practices.
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VILLA, RICCARDO. "The Lpt multiprotein machinery for LPS transport in Gram-negative bacteria:molecular details of the Lpt interactome." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/27959.
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The hallmark of Gram-negative bacteria is their cell envelope, which is composed of two membranes, the inner or cytoplasmic membrane (IM), and the outer membrane (OM), separated by a compartment (the periplasm) that contains a thin peptidoglycan layer. Lipopolysaccharide (LPS) is the major component of the OM, and it acts as a selective barrier together with the OM proteins (OMPs), preventing the entry of many toxic molecules into the cell. Despite the structure and composition of OM have been elucidated in pivotal studies in the 50s and in the 70s, the factors required for the assembly of this organelle have only recently been identified.
LPS, once it is synthesized in the cytoplasm, has to be translocated through out the cell envelope. Seven essential proteins cooperate in a unique fashion to extract the macromolecule from the IM and deliver it in the outer leaflet of the OM. LptBCFG form the IM complex that empowers the translocation process by ATP hydrolysis (Narita and Tokuda, 2009), LptDE constitute a complex embedded in the OM that finally flips LPS across the OM and deliver it to its final destination (Chng et al., 2010a; Freinkman et al., 2011), and LptA is a periplasmic protein that contacts both the IM and OM complexes (Sperandeo et al. 2007; Tran et al., 2008).
Notably, LptC is single-pass IM protein with a large periplasm-protruding region.
LptC single mutants were obtained in this work by random-mutagenesis, and used in vivo and in vitro experiments to characterize two regions of the protein that distinctly interact with LptA and the IM protein complex LptBFG, respectively.
Chimera versions of LptC, either missing the transmembrane (TM) sequence, or with the IM anchor substituted by a heterologous sequence, were additionally constructed to this purpose.
Moreover, Both LptA and LptC were previously demonstrated to bind LPS in vitro, here it is presented a rapid bioinformatic tool which has been implemented to discover the molecular determinants of LptA for the interaction with Lipid A, the main component of LPS.
Genetic evidences previously obtained in our laboratory together with the presented data strongly support the LPS transport machinery model defined as the trans-envelope complex by Chng and coworkers (Chng et al., 2010a): indeed LptA interacts both with the IM and the OM protein complexes (LptBCFG and LptDE respectively), bridging them together. In support of this model, a phylogeny and structural motif conservation analysis of the Lpt components suggests that the unique structural domain retained in these proteins—despite the low sequence similarity—is the key to make possible the interaction between all the Lpt components.
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Dycus, Linda Gail. "Leadership Practices of School Nutrition Professionals." Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etd/2160.
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School-aged children's nutritional needs have changed from a 1946 underweight and undernourished population to rapidly increasing numbers of overweight and obese children with associated health complications. The purpose of this quantitative study was to explore leadership practices of state and system school nutrition professionals. By obtaining information regarding the past and present practices of school nutrition professionals, this researcher strove to provide insight into best practices for future leaders.
Electronic mail messages linked to Kouzes and Posner's (1995) self-reporting leadership practices survey were sent to 194 Tennessee school nutrition professionals (53 state directors and 141 system supervisors). The survey had a response rate of 40.7%. Descriptive statistics and content analysis were used to analyze responses from the survey's participants.
Findings of the study provided a reflection of current school nutrition professionals' leadership practices and a demographic profile of school nutrition professionals. School nutrition professionals tend to have exemplary leadership skills as measured by the LPI compared to Kouzes-Posner mean scores. Of the nutrition professionals, 68% reported plans to retire in 10 or fewer years. Current school nutrition professionals primarily come from the ranks of existing school instructional personnel. A majority of the school supervisors held associate or bachelor degrees. State directors tended to have degrees at masters or doctorate level. A small number had postsecondary professional training in nutrition and disease. Over half had some type of training in nutrition.
The findings of the study resulted in several suggestions for the school nutrition professional of the future including creation of specialized degree programs and internships at the post secondary level to train future candidates for the job as school nutrition professionals. Today's school nutrition professionals' postsecondary curriculum content could be lacking essential nutrition content area and might not be reflective of the current school population's nutritional risks, needs, and best practices of preventions and/or treatments.
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Sarmah, Dipsikha. "Evaluation of Spatial Interpolation Techniques Built in the Geostatistical Analyst Using Indoor Radon Data for Ohio,USA." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1350048688.
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Cavins, Bryan Jeremy. "The Relationship between Emotional-Social Intelligence and Leadership Practices among College Student Leaders." Bowling Green State University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1131374548.
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Terra, Luciana Bomfim. "A implementação da Lei de Acesso à Informação (LAI) na Universidade Federal da Bahia." Escola de Administração da Universidade Federal da Bahia, 2014. http://repositorio.ufba.br/ri/handle/ri/17220.
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A implementação da Lei de Acesso à Informação, no Brasil, é um tema ainda pouco explorado, tendo em vista a recente aprovação da Lei 12.527/2011, que entrou em vigor em 16 de maio de 2012, através do Decreto 7.724. Esta pesquisa teve como objetivo a analise de como a Universidade Federal da Bahia vem implementando a LAI e como vem acontecendo a produção e a disponibilização das informações para o cidadão, sob a ótica da transparência apregoada pela Controladoria-Geral da União. Para isso, foram utilizados os parâmetros teóricos, baseados nos estudos de Carter, Neuman e Calland que foram organizados em três dimensões: legal, institucional e social. Através da pesquisa documental e de entrevistas realizadas com os servidores da UFBA, foi possível desenvolver o estudo de caso, numa abordagem qualitativa. Com os resultados alcançados, conclui-se que a UFBA vem atendendo às exigências legais, parcialmente, e não está preparada para a aplicação dos procedimentos necessários a fim de que a implementação da lei aconteça efetivamente. Dessa forma, está despreparada para assumir o compromisso com a transparência das informações governamentais. The implementation of the Law on Access to Information, in Brazil, is still a relatively unexplored subject in view of the recent adoption of the Law 12.527/2011, which entered into force on May 16, 2012, through Decree 7.724 This research aimed to examine how the Universidade Federal da Bahia has been implementing the LAI is happening and how the production and provision of information to the citizens, from the perspective of transparency touted by the Controladoria Geral da União. For this, we used the theoretical parameters, based on studies of Carter, Neuman and Calland which were organized in three dimensions: legal, institutional and social. Through desk research and interviews with the officers of the University, it was possible to develop the case study, a qualitative descriptive approach. With a results obtained, it is concluded that the UFBA been meeting the legal requirements, partly, but is not prepared to the implementation of the necessary procedures to ensure that the implementation of the law effectively happen. Thus, is unprepared to commit to transparency of government information. Keywords:
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Kumar, Abhishek. "Convex Modeling Techniques for Aircraft Control." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33530.
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The need to design a controller that self-schedules itself during the flight of an aircraft has been an active area of research. New methods have been developed beyond the traditional gain-scheduling approach. One such design method leads to a linear parameter varying (LPV) controller that changes based on the real-time variation of system dynamics. Before such a controller can be designed, the system has to also be represented as an LPV system. The current effort proposes a LPV modeling technique that is inspired by an affine LPV modeling techniques found in recent research. The properties of the proposed modeling method are investigated and compared to the affine modeling technique. It is shown that the proposed modeling technique represents the actual system behavior more closely than the existing affine modeling technique.
To study the effect of the two LPV modeling techniques on controller design, a linear quadratic regulator (LQR) controller using linear matrix inequality (LMI) formulation is designed. This control design method provides a measure of conservatism that is used to compare the controllers based on the different modeling techniques. An F-16 short-period model is used to implement the modeling techniques and design the controllers. It was found that the controller based on the proposed LPV modeling method is less conservative than the controller based on the existing LPV method. Interesting features of LMI formulation for multiple plant models were also discovered during the exercise.
A stability robustness analysis was also conducted as an additional comparison of the performance of the controllers designed using the two modeling methods. A scalar measure, called the probability of instability, is used as a measure of robustness. It was found that the controller based on the proposed modeling technique has the necessary robustness properties even though it is less conservative than the controller designed based on the existing modeling approach.Master of Science
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Costa, Natalia de Souza Xavier. "Efeito da exposição ao material particulado atmosférico no desenvolvimento da lesão pulmonar aguda (LPA) induzida por LPS." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-24112015-102031/.
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Estudos epidemiológicos e experimentais mostram que a poluição do ar pode causar diversos efeitos adversos na saúde, dentre eles inflamação sistêmica e pulmonar, doenças cardiovasculares e exacerbação de doenças pré-existentes. A síndrome do desconforto respiratório aguda é caraterizada por intenso infiltrado inflamatório, dano na barreira alvéolo-capilar e hipoxemia, e desde a sua descrição em 1967 ainda apresenta elevados índices de mortalidade. O presente estudo tem como objetivos: 1. Avaliar qual o impacto da poluição atmosférica de uma região urbana sobre a progressão da LPA induzida por LPS; e 2. Avaliar se a lesão induzida por LPS é alterada em um indivíduo previamente exposto à poluição atmosférica. Os principais achados relativos ao objetivo 1 mostram que, de uma forma geral, quando há a interação do material particulado fino (MP2,5) anterior à fase aguda da LPA, esta não se desenvolve de forma tão grave. Quanto aos parâmetros inflamatórios, nota-se que, na maioria dos parâmetros, as células inflamatórias e citocinas pró-inflamatórias aumentam no grupo LPS 24 horas, mas não, ou não tanto quanto, no grupo poluição+LPS. Como base nestes resultados podemos hipotetizar que pode ter ocorrido uma alteração do perfil da resposta inflamatória ou imunotoxicidade. Quando observamos os resultados referente ao objetivo 2, nota-se que, o grupo LPS + poluição permanece em um estado inflamatório persistente com número de leucócitos aumentado no lavado bronco-alveolar e níveis elevados de citocinas pró-inflamatórias (IL-1beta, IL-6 e IL-8) no tecido pulmonar, enquanto o grupo LPS 5 semanas tem estes parâmetros mais próximos do grupo controle. Na morfologia tecidual, o grupo LPS + poluição a diminuição do espaço aéreo alveolar e o espessamento septal. É bastante plausível que a poluição do ar dificulte recuperação e o reparo adequado da lesão causada pelo LPS, uma vez que a poluição do ar, e especialmente o material particulado fino, exerce um papel pró-inflamatório contínuo sobre a lesão. Podemos concluir que: o uso do LPS por nebulização é um modelo viável para a reprodução dos parâmetros característicos da lesão pulmonar aguda, a exposição ao material particulado pode alterar o perfil de resposta imediata (24 horas) na lesão pulmonar aguda e pode dificultar a recuperação da lesão. Estudo adicionais são necessários para entender o possível papel da modulação da resposta imunológica nos mecanismos envolvidos nestes processosEpidemiological and experimental studies show that the air pollution can cause several harmful outcomes to the health, which include systemic and pulmonary inflammation, cardiovascular diseases, and exacerbation of preexisting diseases. The acute respiratory distress syndrome is characterized by intense inflammatory response, alveolo-capillary barrier damage and hypoxemia and since it was described for the first time in 1967 it still has high mortality rates. This study aims to 1. Evaluate the impact of urban air pollution exposure on the acute lung injury progression and 2. Evaluate if the LPS-induced injury is altered in an individual previously exposed to the air pollution. The main findings regarding objective 1 show that when there is an interaction of the particulate matter on the acute phase of LPS-induced injury, the lesion is not as severe as in the group that received only LPS. The inflammatory parameters show that inflammatory cells and pro inflammatory cytokines are increased in the LPS 24 hour, whereas not, or not as much as, in the air pollution + LPS group. Based on these results, we can hypothesize that may have occurred a shift of the inflammatory profile or immunotoxicity. Results of the objective 2 show that the group LPS + air pollution remains in a persistent inflammatory condition with increased leucocytes in BALF and pro inflammatory cytokines (IL-1beta, IL-6 e IL-8) also increased in the lung tissue, while the LPS 5 weeks group shows these parameters levels closer to the control group. The tissue morphology displays a diminished alveolar air space and septal thickening. It is very likely that the air pollution interferes on the adequate LPS-induced lesion recovery and repair, once that the air pollution, specially the fine particulate matter, has a continuous pro-inflammatory role over the lesion. We can conclude that: the use of nebulized LPS is a feasible acute lung injury model; the exposure to the particulate matter could alter the profile of the immediate response (24 hours) of the acute lung injury and it can impair the lesion recovery. Additional studies are necessary to understand the possible role of the immunological response modulation mechanisms involved in these processes
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Colaitis, Arnaud. "Multiscale description of the laser-plasma interaction : application to the physics of shock ignition in inertial confinement fusion." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0253/document.
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Ce manuscrit présente une nouvelle formulation de l’Interaction Laser-Plasma (ILP) à l’échelle hydrodynamique, qui couple la dynamique du plasma avec les processus d’ILP linéaires et non-linéaires. Le modèle standard du tracé de rayon (Ray-Tracing), basé sur l’Optique Géométrique, est peu adapté pour modéliser l’ILP non-linéaire car la distribution de l’intensité laser dans le plasma n’est pas directement disponible. Nous proposons un modèle alternatif spécifiquement formulé pour un code hydrodynamique Lagrangien, basé sur l’Optique Géométrique Complexe Paraxiale qui décrit la propagation de faisceaux Gaussiens. Cette méthode est ensuite adaptée à la description de faisceaux laser non Gaussiens, et permet de reproduire la statistique d’intensité, l’enveloppe et le contraste de faisceaux lissés par une Lame de Phase. Nous proposons des modèles en ligne pour décrire l’échange d’énergie entre faisceaux croisés (CBET) et la génération d’électrons rapides par l’ILP non-linéaire, en utilisant PCGO. Le modèle en ligne de CBET est validé par comparaison avec un code de propagation d’une onde électromagnétique paraxial conventionnel dans le cas d’un plasma inhomogène en vitesse. Un bon accord est trouvé après une période transitoire de l’ordre de la picoseconde, notamment en ce qui concerne la distribution spatiale de l’intensité laser et des perturbations de densité du plasma. Ce modèle appliqué à une configuration d’attaque directe de Fusion par Confinement Inertiel (FCI) montre que le CBET réduit le couplage laser-cible, réduit le facteur de convergence, et amplifie les modes basse fréquence de déformation de la capsule. Le modèle de génération d’électrons rapides par l’ILP non-linéaire modélise les propriétés des faisceaux d’électrons rapides, i.e. leur flux, énergie moyenne, dispersions angulaire et direction, à partir de l’intensité laser prédite par PCGO et à partir d’expressions simplifiées, basées sur des modèles théoriques et des lois d’échelles obtenues à l’aide de simulations cinétiques. La propagation et le dépôt d’énergie par les électrons rapides est décrite à partir d’une approximation de diffusion angulaire adaptée en deux dimensions, pour des faisceaux de profil transverse d’intensité Gaussien, de distribution d’énergie exponentielle et d’ouverture angulaire arbitraire. Ce modèle couplé rend compte de (i) la compétition pour l’énergie laser entre les différentes instabilités et avec l’absorption collisionnelle, (ii) le couplage entre l’ILP non-linéaire et la dynamique du plasma à travers les faisceaux d’électrons rapides, et(iii) la perte de couplage laser-plasma due à la diffusion Raman arrière. Les performances de ce modèle sont évaluées par comparaisons avec des expériences d’allumage par choc conduites sur les installations laser Omega et Pals. Ce modèle multi-échelle est ensuite utilisé pour interpréter plusieurs expériences. On trouve notamment que les électrons générés par l’ILP non-linéaire augmentent la vitesse du choc et la pression en aval de ce dernier, tout en réduisant sa force et la pression d’ablation. Une application à la phase fortement non-linéaire de l’allumage par choc en FCI suggère que ces électrons sont néfastes pour l’implosion de la capsule en ce qui concerne les cibles conventionnelles : ceux-ci causent une augmentation de la masse du point chaud et des pertes radiatives. Ce modèle peut être appliqué à la modélisation hydrodynamique des expériences laser-cible de physique des hautes densités d’énergie pour les régimes d’interaction pertinents pour les instabilités évoquées ci dessusThis manuscript presents a novel formulation of the Laser-Plasma Interaction (LPI) at hydrodynamical scales, that couples the plasma dynamics with linear and nonlinear LPI processes. The standard Ray Tracing model, based on Geometrical Optics, is not well suited for that purpose because it does not readily describe the laser intensity distribution in plasma. We propose an alternative model formulated for a Lagrangian hydrodynamic code. It is based on the ray-based Paraxial Complex Geometrical Optics (PCGO) that describes Gaussian optical beamlets. A method for modeling non-Gaussian laser beams smoothed by Phase Plates is presented, that allows to create intensity variations that reproduce the beam envelope, contrast and high-intensity statistics predicted by paraxial laser propagation codes. We propose inline reduced models for the non-linear laser-plasma interaction, in the case of the Cross-Beam Energy Transfer (CBET) and the generation of Hot Electrons (HE). The inline CBET model is validated against a time-dependent conventional paraxial electromagnetic wave propagation code, in a well-defined plasma configuration with density and velocity profiles corresponding to an inhomogeneous plasma. Good agreement is found past a transient period on the picosecond time scale, notably for the spatial distribution of density perturbations and laser intensities in the interaction region. Application of the model to a direct-drive Inertial Confinement Fusion (ICF) configuration shows that CBET significantly degrades the irradiation symmetry by amplifying low frequency modes and reducing the laser-capsule coupling efficiency, ultimately leading to large modulations of the shell areal density and lower convergence ratios. The LPI/HE model predicts the HE fluxes, temperatures, angular dispersion and direction from the laser intensity of PCGO beamlets from simplified expressions based on theoretical models and scaling laws obtained in kinetic simulations. The HE beams propagation and energy deposition in plasma is described in the angular scattering approximation, adapted to two-dimensional, transversally Gaussian, multigroup HE beams of arbitrary angular distribution. This model accounts for (i) competition for the laser energy between the various instabilities and with the linear collisional absorption, (ii) coupling between nonlinear LPIs and plasma dynamics via the high energy electron beams and(iii) loss of coupling due to backscattered Raman light. Its performance is confirmed by comparison with measurements of shock timing, laser absorption, HE fluxes and temperatures in experiments conducted on Omega and Pals laser facilities. This multiscale inline LPI-HE model is used to interpret several Shock Ignition experiments. It is found that HEs from parametric instabilities significantly increase the shock pressure and velocity in the target, while decreasing its strength and the overall ablation pressure. Applications to the high-intensity regime of shock ignition ICF suggest that HEs generated by the nonlinear LPI are nefarious to the capsule implosion in conventional target designs, as they lead to a dramatic increase in the hotspot mass and losses by Bremsstrahlung radiation. This model is readily applicable to hydrodynamic description of laser-target experiments of High Energy Density Physics, in the interaction regimes involving the above-mentioned non-linear LPI processes
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Luzi, Alexandru. "Commande variant dans le temps pour le contrôle d'attitude de satellites." Thesis, Toulouse, ISAE, 2014. http://www.theses.fr/2014ESAE0006/document.
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Cette thèse porte sur la commande variant dans le temps avec comme fil directeur l’application au contrôle d’attitude de satellites. Nous avons étudié trois types de commande: une commande à commutation, une commande LPV et une commande adaptative directe. Pour cette dernière nous avons proposé des résultats théoriques nouveaux portant sur la structuration du gain et de l’adaptation. Les résultats ont été validés en simulation et sont testés à bord d’un satellite. En partant de la loi à commutation actuellement utilisée sur les satellites Myriade, une première partie de nos travaux est dédiée à la commande LPV. Notre approche, basée sur la spécification des objectifs de commande à travers un modèle de référence LPV, permet d'obtenir de nouveaux algorithmes exprimés dans ce formalisme. Testées en simulation, ces lois de commande répondent à la problématique de notre application. Toutefois, le choix du modèle de référence LPV s'avère délicat. Cette difficulté a été levée en utilisant la commande adaptative. Dans cette approche, les spécifications sur le comportement temps-variant sont traduites par des contraintes au niveau des lois d'adaptation des gains de commande. Nous introduisons ainsi une nouvelle méthode de synthèse de lois adaptatives structurées. Les preuves de stabilité établies s'appuient sur des outils de la théorie de Lyapunov. Les résultats obtenus sur un simulateur complet montrent l'intérêt de tels algorithmes adaptatifs. Ils permettent en particulier de modifier la dynamique du satellite selon les capacités disponibles des actionneurs. Sur la base de ces résultats, une campagne d’essai en vol sur le satellite PICARD est actuellement en coursThis manuscript considers time varying control, with a strong emphasis on a satellite attitude control application. Three types of control structures have been studied: a switch-based approach, LPV control and direct adaptive control. In this last field we have introduced new theoretical results which allow structuring the gain and the adaptation law. The results have been validated in simulation and are currently tested on board a satellite. Starting from the switch-based control law currently implemented on the Myriade satellites, a first part of our work isdedicated to LPV control. Based on the specification of the control objectives by using of an LPV reference model, our approach allows obtaining new control algorithms expressed within this framework. The simulations carried out with theLPV algorithms obtained by using this method show that they meet the needs of our application. Nonetheless, the choice of a reference model proves to be difficult. This obstacle has been surpassed by using direct adaptive control. In this approach, specifications regarding the timevarying behaviour are added through constraints on the laws defining the control gains adaptation. We thus introduce anew synthesis method, based on which structured adaptive control laws are obtained. Stability proofs are established based on tools of the Lyapunov theory.The results obtained on a complete simulator show the interest of using such adaptive algorithms, which allow in particular to modify the satellite dynamics depending on the available capacity of the actuators. Based on these positive results, a fight-test campaign on the PICARD satellite is underway
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Abdallaoui, Berrada Chakir, and aida Ciro. "Bottlenecks in the Freight Forwarding sector in West - coast Africa." Thesis, Jönköping University, Jönköping International Business School, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-9589.
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Problem – The expansion of global trade and supply chain integration has put great emphasison logistics, particularly in the intermediary sector, freight forwarders. Whilst in developedcountries freight forwarders benefit from competitive markets and trade facilitatingpolicies, this sector in West coast Africa exhibits low logistics performance levels. Inorder to address such issues, one needs to analyse the problem and identify the causes; thisthesis focuses on identifying the bottlenecks in the freight-forwarding sector in west coastAfrica.Purpose – The main purpose of this study is to identify the bottleneck/s within thefreight-forwarding industry in west coast Africa, namely: Angola, Cameroon, DR of Congo,Gabon, and Nigeria.Method – This thesis employs a pre-study and case study method, to ensure sufficient collectionof relevant material, taking into account the lack of research in this subject. We usedthe material obtained from the interviews and the secondary source, to structure our purpose,research questions, and to define the case of our study.Results – The study concludes with a series of interesting findings; First, the activity of aFreight Forwarder depends on a series of factors that do not depend on the Freight Forwarderper se. And second, Freight Forwarders in order to accomplish their tasks, have accessto services that are shared by all providers, and that are beyond their control. To conclude,the study identifies infrastructure as a major bottleneck in the Freight Forwarding sector.
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De, Hillerin Safta. "Commande robuste de systèmes non linéaires incertains." Thesis, Supélec, 2011. http://www.theses.fr/2011SUPL0015/document.
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Cette thèse étudie l'approche LPV pour la commande robuste des systèmes non linéaires. Son originalité est de proposer pour la première fois un cadre rigoureux permettant de résoudre efficacement des problèmes de synthèse non linéaire. L'approche LPV a été proposée comme une extension de l'approche H-infini dans le contexte des systèmes LPV (« Linéaires à Paramètres Variant dans le temps »), voire non linéaires. Quoique prometteuse, cette approche pour la commande des systèmes non linéaires restait peu utilisée. En effet, au-delà même de certaines limitations théoriques, la nature des solutions obtenues semblait inadéquate. Cette question ouverte est notre point de départ. Nous montrons tout d'abord que la faible variation des correcteurs constatée est due avant tout à la nature du schéma informationnel utilisé traditionnellement lors de la synthèse LPV, et que sous des hypothèses raisonnables, le cadre LPV peut permettre de recouvrir des stratégies de type « linéarisation par bouclage ». Ce point étant acquis, une deuxième difficulté réside dans l'obtention effective de correcteurs non linéaires donnant des garanties de performance. Nous proposons un cadre rigoureux permettant de résoudre efficacement un problème de synthèse incrémentale pondérée, par la résolution d'un problème LPV associé à un schéma informationnel spécifique compatible avec celui identifié dans la première partie. Cette étude et son aboutissement à la définition d'un cadre formel et d'une procédure complète d'obtention de correcteurs, incluant des méthodes de réduction de complexité, donnent des arguments puissants en faveur de l'approche LPV pour la commande robuste de systèmes non linéairesThis thesis studies the LPV approach for the robust control of nonlinear systems. Its originality is to propose for the first time a rigorous framework allowing to solve efficiently nonlinear synthesis problems.The LPV approach was proposed as an extension of the H-infinity approach in the context of LPV (Linear Parameter-Varying) systems and nonlinear systems. Although this approach seemed promising, it was not much used in practise. Indeed, beyond certain theoretical limitations, the nature itself of the obtained solutions did not seem adequate. This open question constitutes the starting point of our work.We first prove that the observed weak variation of the controllers is in fact mostly due to the information structure traditionally used for LPV synthesis, and that under reasonable assumptions, the LPV framework can overlap feedback linearization strategies. This point having been resolved, a second difficulty lies in the actual achievement of nonlinear controllers yielding performance guarantees. We propose a rigorous framework allowing to solve efficiently an incremental synthesis problem, through the resolution of an LPV problem associated to a specific information structure compatible with the one identified in the first part.This study and its corollary description of a formal framework and of a complete controller synthesis procedure, including complexity reduction methods, provide powerful arguments in favor of the LPV approach for the robust control of nonlinear systems
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Nownes, Anthony J., and Colin Glennon. "An Experimental Investigation of How Judicial Elections Affect Public Faith in the Judicial System." Digital Commons @ East Tennessee State University, 2015. https://doi.org/10.1111/lsi.12159.
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Judicial scholars have often speculated about the impact of elections on the administration of justice in the state courts. Yet relatively little research has concerned itself with public perceptions of state court selection methods. Of particular interest is the concept of legitimacy. Do elections negatively affect public perceptions of judicial legitimacy? Bonneau and Hall (2009) and Gibson (2012) answer this question with an emphatic “No.” Judicial elections, these studies show, are not uniquely troublesome for perceptions of institutional legitimacy. This article aims to extend the findings of Bonneau and Hall and Gibson via a laboratory experiment on the effects of elections on public perceptions of judicial legitimacy. In the end, we find that because elections preempt the use of the other main selection method—appointment—they actually enhance perceptions of judicial legitimacy rather than diminish them.
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Falchi, F. A. "OUTER MEMBRANE BIOGENESIS IN ESCHERICHIA COLI: GENETIC AND PHYSIOLOGICAL CELL RESPONSE TO LIPOPOLYSACCHARIDE TRANSPORT DEFECTS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/342548.
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The outer membrane (OM) of Gram-negative bacteria is an asymmetric bilayer formed by phospholipids in the inner leaflet and lipopolysaccharide (LPS) in the outer leaflet, with a large number of embedded or associated proteins. The primary function of this structure essential for Gram-negative viability is to establish an additional selective permeability barrier that enables the cell to maintain favourable intracellular conditions even in harsh environments and the LPS layer greatly contributes to this peculiar property. The transport of LPS to the cell surface is an essential process for OM biogenesis; the LPS transport (Lpt) system, originally identified in E. coli, is the protein machine responsible for LPS delivery from the periplasmic side of the inner membrane (IM) to the OM. It is composed of seven proteins forming a complex which spans from IM to OM. At the IM the ABC transporter LptBFG, associated to the membrane-bound protein LptC interacts with the periplasmic protein LptA that connects, through structurally conserved domains, the IM ABC transporter with the OM translocon LptDE, responsible for LPS assembly at the cell surface.
In order to gain more insight in the mechanism of LPS transport and more in general in OM homeostasis we used both a genetic and a proteomic approach. The former was based on the selection of suppressors of LPS transport defects obtained with two different types of mutants. i) a quadruple non-lethal lptA mutant (lptA41) that displayed increased sensitivity to toxic compounds, and ii) a lethal deletion mutant of lptC.
Genome sequencing analysis of spontaneous suppressors of lptA41 phenotype revealed two different mechanism of suppression: one mechanism involves the Mla system, a protein machinery which contributes to maintain OM asymmetry; the second mechanism involves both an intragenic mutation improving LptA41 protein stability and an extragenic mutation affecting osmoregulated periplasmic glucans (OPGs) synthesis.
Viable mutants lacking lptC were obtained using a plasmid shuffling technique. Genome sequencing of such mutants revealed single amino acid substitutions at the R212 residue of the IM component LptF (lptFSupmutants). Our results suggest that LptC may serve as a chaperon of the Lpt machine assembly and/or activity rather than an essential structural component and the periplasmic domain of LptF might be implicated in the formation of the Lpt bridge.
The latter approach consisted of the analysis of differential envelope proteins content of an E. coli lptC conditional expression mutant upon depletion of LptC and thus impairment of LPS transport. By two-dimensional chromatography coupled to tandem mass spectrometry (Multidimensional Protein Identification Technology, MudPIT) we identified 123 proteins whose level is significantly modulated upon LptC depletion. Most of these proteins belong to pathways that contribute to repair OM and restore its permeability barrier properties, including protein involved in maintaining OM asymmetry, in the synthesis of phospholipids and exopolysaccharides as substrate for lipid A modification enzymes, and in peptidoglycan synthesis/remodelling.
Overall these data contribute to our understanding of the multiple strategies that E. coli cells may adopt to respond to perturbations of the OM permeability barrier and to restore OM functionality.
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Carmi, Chen. "Lai." Thesis, California State University, Long Beach, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1523180.
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This project, a film made of short video clips and still photographs, is a continuation of my observation of the urban birds of L.A County: pigeons, seagulls, and herons. There are two other sides that complete the triangle my work relies on: the Hispanic community, which is indirectly present in this document, and me, the outsider/wanderer. This triangle captures an essence of strangeness and uninvited existence that I find in this town, but can be found anywhere else.
I chose the format of the projected film because of its "lack of weight." I like the idea that the project has no real physical presence, that it is all data, or memory. Edward Limonov wrote that back in Russia, he had many books, but immigrants do not have books and now he has only three. I feel much the same about art objects and I find it appropriate that once I leave, carrying a compact disc in its case with me, I will leave no traces behind.
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Bui-Tuan, Viet Long. "Stability and stabilization of linear parameter-varying and time-varying delay systems with actuators saturation." Electronic Thesis or Diss., Amiens, 2022. http://www.theses.fr/2022AMIE0082.
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La thèse est consacrée au développement d'une méthodologie de stabilité et de stabilisation pour les systèmes linéaires paramètres-dépendants et à retard soumis à la saturation de la commande. Dans le processus industriel, l'amplitude du signal de commande est généralement limitée par les contraintes de sécurité, les limites du cycle physique, etc. Pour cette raison, un outil de synthèse et d'analyse approprié est nécessaire pour décrire avec précision les caractéristiques des systèmes saturés à paramètres linéaires variables. Dans la première partie, une forme dépendante des paramètres de la condition de secteur généralisée (GSC) est considérée pour résoudre le problème de stabilisation saturée. Plusieurs stratégies de contrôle de rétroaction sont étudiées pour stabiliser les systèmes LPV/qLPV saturés. Conditions de stabilisation nécessaires et suffisantes via la formulation d'inégalité matricielle linéaire paramétrée proposée pour les contrôleurs de retour d'état conformes aux exigences de conception (c'est-à-dire l'ensemble admissible des conditions initiales, la région estimée du domaine de convergence asymptotique, la stabilité et les performances robustes sous l'influence des perturbations, etc.). La relaxation des PLMI conçus est illustrée par les résultats de comparaison à l'aide d'une fonction de Lyapunov dépendante des paramètres. Dans la deuxième partie, les développements de stabilité dépendant du délai basés sur la fonctionnelle de Lyapunov-Krasovskii (LKF) sont présentés. Les techniques modernes de limitation avancées sont utilisées avec un équilibre entre conservatisme et complexité de calcul. Ensuite, des analyses de stabilisation de saturation pour les contrôleurs d'ordonnancement de gain. Inspirée des méthodes de système à retard incertain, une nouvelle condition de stabilisation est dérivée de l'analyse de stabilisation dépendante du retard pour le système à retard LPV soumis à des contraintes de saturation. Dans cet aspect, les contrôleurs de rétroaction à programmation de gain stabilisants améliorent les performances et la stabilité du système saturé et fournissent un grand domaine d'attraction. On peut souligner que la formulation dérivée est générale et peut être utilisée pour le contrôle de la conception de nombreux systèmes dynamiques. Enfin, pour maximiser la région d'attraction tout en garantissant la stabilité asymptotique du système en boucle fermée, un problème d'optimisation est inclus dans la stratégie de conception de commande proposéeThe dissertation is devoted to developing a methodology of stability and stabilization for the linear parameter-dependent (PD) and time-delay systems (TDSs) subject to control saturation. In the industrial process, control signal magnitude is usually bounded by the safety constraints, the physical cycle limits, and so on. For this reason, a suitable synthesis and analysis tool is needed to accurately describe the characteristics of the saturated linear parameter-varying (LPV) systems. In the part one, a parameter-dependent form of the generalized sector condition (GSC) is considered to solve the saturated stabilization problem. Several feedback control strategies are investigated to stabilize the saturated LPV/qLPV systems. Necessary and sufficient stabilization conditions via the parameterized linear matrix inequality (PLMI) formulation proposed for the feedback controllers conforming to the design requirements (i.e., the admissible set of the initial conditions, the estimated region of the asymptotic convergence domain, the robust stability and performance with the influence of perturbations, Etc.). The relaxation of the designed PLMIs is shown through the comparison results using a parameter-dependent Lyapunov function (PDLF). In the second part, the delay-dependent stability developments based on Lyapunov-Krasovskii functional (LKF) are presented. The modern advanced bounding techniques are utilized with a balance between conservatism and computational complexity. Then, saturation stabilization analyzes for the gain-scheduling controllers. Inspired by uncertain delay system methods, a novel stabilization condition is derived from the delay-dependent stabilizing analysis for the LPV time-delay system subject to saturation constraints. In this aspect, the stabilizing gain-scheduling feedback controllers improve the performance and stability of the saturated system and provide a large attraction domain. It can be emphasized that the derived formulation is general and can be used for the design control of many dynamic systems. Finally, to maximize the attraction region while guaranteeing the asymptotic stability of the closed-loop system, an optimization problem is included to the proposed control design strategy
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Luca, Anamaria. "Outils ensemblistes d'analyse et de synthèse des lois de commande robustes pour des systèmes incertains." Phd thesis, Supélec, 2011. http://tel.archives-ouvertes.fr/tel-00630954.
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Le travail de recherche concrétisé par ce mémoire de thèse se trouve à l'intersection de deux domaines importants, la commande robuste des systèmes linéaires (LTI, LPV, en commutation) à temps discret affectés par des perturbations permanentes bornées et des contraintes et les ensembles invariants ellipsoïdaux maximal ou minimal. La première partie de ce mémoire se focalise sur l'analyse de la stabilité entrée-état (en anglais ISS) du système par rapport à une perturbation bornée et le calcul des ensembles invariants ellipsoïdaux minimal ou maximal (ou sous forme d'ellipsoïdes tronqués) satisfaisant les contraintes. La deuxième partie envisage la synthèse d'une commande par retour d'état ISS stable et robuste vis-à-vis de perturbations bornées, garantissant l'ellipsoïde invariant maximal satisfaisant les contraintes ; puis la synthèse d'une loi decommande par retour d'état et observateur ISS stable vis-à-vis de perturbations bornées, garantissant une certaine performance ; enfin la synthèse d'un paramètre de Youla afin de garantir la projection maximale sur le sous-espace de l'état initial. La projection obtenue possède alors un volume plus grand que celui obtenu sans le paramètre de Youla d'où une amélioration en termes de robustesse. Une dernière étape vise à obtenirun compromis entre la robustesse et la performance en utilisant des critères basés sur le placement de pôles ou sur la vitesse de décroissance de la fonction de Lyapunov. Tous les résultats théoriques obtenus sont exprimés sous forme d'inégalités matricielles et sont validés en simulation et de façon expérimentale dans le cadre de la commande d'un convertisseur de puissance.
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Lei, Lei [Verfasser]. "Ligand-kontrollierte regioselektive Kreuzkupplungsreaktionen an Thiophenen / Lei Lei." München : Verlag Dr. Hut, 2011. http://d-nb.info/1010446940/34.
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