International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The requirement for improved ramp telemetry data and video coverage has prompted the Telemetry Branch at the Naval Air Warfare Center Aircraft Division (NAWCAD) to install an L and S-Band Fiberoptic Transmission System linking multiple hangar locations to the Telemetry Data Center. This system uses Commercial-off-the-Shelf (COTS) equipment and is capable of transmitting analog telemetry data and video from multiple sites to one location for processing and display. The system at NAWCAD has been in use since 1996 and is continually growing to accommodate additional requirements.

Transmission Control Protocol (TCP) is considered one of the most important protocols in the Internet. An important mechanism in TCP is the congestion control mechanism which controls TCP sending rate and makes TCP react to congestion signals. Nowadays in heterogeneous networks, TCP may work in networks with some links that have lossy nature (wireless networks for example). TCP treats all packet loss as if they were due to congestion. Consequently, when used in networks that have lossy links, TCP reduces sending rate aggressively when there are transmission (non-congestion) errors in an uncongested network. One solution to the problem is to discriminate between errors; to deal with congestion errors by reducing TCP sending rate and use other actions for transmission errors. In this work we investigate the problem and propose a solution using an end-to-end error discriminator. The error discriminator will improve the current congestion window mechanism in TCP and decide when to cut and how much to cut the congestion window. We have identified three areas where TCP interacts with drops: congestion window update mechanism, retransmission mechanism and timeout mechanism. All of these mechanisms are part of the TCP congestion control mechanism. We propose changes to each of these mechanisms in order to allow TCP to cope with transmission errors. We propose a new TCP congestion window action (CWA) for transmission errors by delaying the window cut decision until TCP receives all duplicate acknowledgments for a given window of data (packets in flight). This will give TCP a clear image about the number of drops from this window. The congestion window size is then reduced only by number of dropped packets. Also, we propose a safety mechanism to prevent this algorithm from causing congestion to the network by using an extra congestion window threshold (tthresh) in order to save the safe area where there are no drops of any kind. The second algorithm is a new retransmission action to deal with multiple drops from the same window. This multiple drops action (MDA) will prevent TCP from falling into consecutive timeout events by resending all dropped packets from the same window. A third algorithm is used to calculate a new back-off policy for TCP retransmission timeout based on the network's available bandwidth. This new retransmission timeout action (RTA) helps relating the length of the timeout event with current network conditions, especially with heavy transmission error rates. The three algorithms have been combined and incorporated into a delay based error discriminator. The improvement of the new algorithm is measured along with the impact on the network in terms of congestion drop rate, end-to-end delay, average queue size and fairness of sharing the bottleneck bandwidth. The results show that the proposed error discriminator along with the new actions toward transmission errors has increased the performance of TCP. At the same time it has reduced the load on the network compared to existing error discriminators. Also, the proposed error discriminator has managed to deliver excellent fairness values for sharing the bottleneck bandwidth. Finally improvements to the basic error discriminator have been proposed by using the multiple drops action (MDA) for both transmission and congestion errors. The results showed improvements in the performance as well as decreases in the congestion loss rates when compared to a similar error discriminator.

published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

It is important to ensure that Transpower is prepared to deliver upcoming transmission tower refurbishment projects that are located on sites with difficult access. This project reviews the availability, capability and cost of utilising alternative construction methods and any associated wider issues. The focus of this report is on how Transpower can more effectively utilise helicopters and gin poles for transmission tower erection and material delivery on remote sites.

Viral hepatitis has been a universal human affliction for thousands of years. Only recently has it become understood, and there are still many unanswered questions. This dissertation examines the epidemiology of viral hepatitis in a county in the southwestern United States. An historical review traces the history of concepts of jaundice and details recent advances in the understanding of the transmission of the clinical entities grouped under the heading of viral hepatitis. Age specific incidence rates for all forms of hepatitis in the study population are compared to national rates. Data indicate that the study population experiences higher rates of enteric disease and lower rates of sexually transmitted disease than the nation as a whole. The hypothesis that diseases with similar routes of transmission will be associated with each other and show similar socioeconomic patterns was tested using three year average census tract incidence rates for 1982-84. In almost all samples, hepatitis A and shigellosis are more similar to each other than either is to hepatitis B. A similarity between hepatitis B and syphilis is also evident, but in fewer samples, reflecting their more disparate routes of transmission. Different relationships between incidence rates and socioeconomic variables are evident when the analysis is done using data from the fifty states for 1982. Participant observation as a disease investigator generated information on beliefs about hepatitis among lay and medical personnel. Often these beliefs diverge significantly from accepted facts about hepatitis. These findings have implications for the design of public health programs to control communicable diseases with similar modes of transmission.

Approved for public release; distribution is unlimited / A study of SONET network management applications and the load they impart to the network is conducted to provide a better understanding of the capability of various management approaches. In this study, a SONET network is set up in the Advanced Networking Laboratory of the Naval Postgraduate School using four Cisco ONS 15454s. Next, two Element Management Systems, the Cisco Transport Controller and the Cisco Transport Manager, are deployed onto the SONET network. Subsequently, the network traffic of the Element Management Systems is captured and analyzed using a packet analyzer. Link utilization of the two tools is computed using the first-order statistics of the captured traffic distributions. In addition, the Hurst parameter is estimated using the variance-index plot technique (which uses higher-orders statistics of the modeled distributions) to determine the captured traffic's degree of self-similarity. Finally, the calculated utilization is extrapolated to obtain the link utilization for 2500 network elements (the maximum number supported by the Cisco Transport Manager). The result obtained is useful in determining the maximum number of network elements (Cisco ONS 15454s) that the Cisco Transport Manager can support from a network loading point of view. / Civilian, Ministry of Defense, Singapore

An evaluation of the performance of a SONET management system was conducted to better understand its management capabilities due to network disruptions in the presence of a traffic load. This study analyzed the Cisco Transport Manager (CTM) which manages a testbed of four Cisco ONS15454 optical systems. The network was injected with HTTP and FTP traffic generated by the Spirent Smartbits system installed with TeraMetrics Gigabit Ethernet modules and load calibration configured by the Spirent Avalanche software. To simulate real-world situations, power disruptions were applied to the network while collecting CTM traffic using Ethereal. Using queuing analysis, the arrival rates and service times were computed for various CTM traffic components and a utilization for 2500 network elements (NE) extrapolated. Self-similarity analysis was performed and the logvariance was plotted to extract the Hurst values. Finally, the results and findings were compared with prior research for loading and no-loading cases. The results of this study are useful in determining the maximum number of network elements manageable in a disruptive environment. Final analysis on the effects of link utilization on the queue size showed that the CTM is able to manage more NEs when the network is disrupted. Unfortunately, managing more NEs increases the queue size even though the utilization was found to be 0.83 for 5450 NEs. Consequently, in order to maintain a moderate queue size, the maximum number of NEs manageable was found to be 2495. This value is close to CISCO's specification of a CTM server managing a maximum of 2500 NEs.

Autour de la dialectique perpétuation-réinvention des identités mobiles cette étude s'intéresse à un groupe de migrants amazigh (berbères), du Moyen-Atlas marocain, implanté en Ariège. Il s'agit d'aborder la thématique du lien entre le pays d'origine et le pays de vie, ainsi que les processus de passation, de transformation, de réactivation ou d'omission qui s'opèrent dans la migration, en vue de percevoir et comprendre comment se reconstruit "une berbérité" en France ; il sera question enfin de mettre en évidence les formes de construction d'identités en miroirs, « ici et là-bas », formées à partir des relations constantes qui se font entre les groupes berbères de France et du Maroc. Pour cela je présente les manières de célébrer les événements qui touchent, réunissent et transforment le groupe, ainsi que les manières de tisser le lien, de « cultiver » au quotidien sa place entre différenciation et appartenance. C'est dans la rencontre entre générations, entre migrants et sédentaires, entre homme et femme, ici comme là-bas, que je tente de questionner les processus d'affiliation et de désaffiliation, du « légitime » et de « l'illégitime », en somme les façons de penser l'inscription dans la communauté. / Built around the dialectics of perpetuation and reinvention of mobile identities, this study focuses on a group of Amazigh _ Berber _ migrants coming from the Middle Atlas in Morocco and settled in Ariège. The theme which is broached here is that of the bond between the country one comes from and the country where one lives, the aim being to perceive and to understand how a 'berberity' reconstructs itself in France ; the issue will then be to reveal the forms of mirror identity constructions - 'here and there' – shaped through the relations that are constantly being established between Berber groups living in France and in Morocco. To this end, I set out how events affecting the group, gathering it together and transforming it are celebrated, as well as how this bond is forged and how its place is 'cultivated' in everyday life between differentiation and belonging. For it is by analyzing the encounter between different generations, between migrant and sedentary people, between man and woman, here as well as there, that I attempt to question the processes of affiliation and disaffiliation, the concepts of 'legitimate' and 'illegitimate' - in short, the way inscription is conceived of within the community.

Les intellectuels byzantins ne lisaient pas les œuvres anciennes de manière passive : en lisant, ils avaient toujours le calame à la main pour corriger les fautes du texte, ajouter des notes ou des scholies marginales, pour rédiger des commentaires ou pour en tirer des citations, qu’ils déposaient dans des cahiers de notes. L’étude d’un recueil d’extraits permet de s’approcher en quelque sorte du bureau d’un érudit du passé, de comprendre quels textes il lisait, pourquoi et comment il sélectionnait les passages à citer. Le Neap. II C 32 est un des témoins les plus remarquables de cette pratique de lecture active et il constitue le reflet des intérêts de lecture d’un érudit ou d’un groupe d’érudits, qui avait l’habitude d’annoter les passages les plus intéressants de toutes les œuvres qu’il lisait. Le codex a été écrit par un seul scribe : on peut l’identifier comme Georges Galésiotès, célèbre copiste professionnel qui travailla pour la chancellerie du patriarcat de Constantinople pendant la première moitié du XIVe siècle. Le Neap. II C 32 n’est pas d’un cahier de notes mais il représente la mise au propre de plusieurs brouillons, qui recueillaient plusieurs anthologies d’extraits. L’ordre du contenu du Neapolitanus ne semble pas fortuit, mais il correspond probablement à un projet précis. Le codex peut être divisé en trois sections : la première contient les extraits tirés de la Bible (ff. 1-27) ; la deuxième ceux sélectionnés des ouvrages à sujet religieux (ff. 28-149) ; la troisième est dédiée à la littérature profane. L’analyse critico-textuelle a permis de tracer la place des modèles de certaines anthologies d’extraits dans le cadre de la tradition directe des ouvrages présents dans le codex de Naples. / Byzantine scholars did not read ancient authors passively: when they read, they always kept a pen in their hands in order to be able to correct eventual mistakes, add notes or scholia, include commentaries. They often employed books to collect interesting quotes, which they annotated separately in handbooks, so that they were ready to be used in the composition of an original work. The study of an anthology of excerpts allows us to somehow approach the writing desk of a scholar of the past: in doing so, it grants us the possibility to understand which texts he read and why, and also analyze the method he used in exploiting his sources. Ms Neap. II C 32 is an exceptional witness of this form of ‘active’ reading. The codex constitutes the reflection of the literary interests of a group of scholars who used to annotate the most interesting passages they found while reading. The codex was written by an only scribe, i.e. George Galesiotes, who worked for the patriarchal chancellery of Constantinople in the first half of the 14th century. Neap. II C 32 is not a scholarly handbook: it is the fair copy of several handbooks. The anthologies of excerpts included in the manuscript have been organized according to a precise project. The codex can thus be divided into three main sections: the first one is dedicated to the Bible (ff. 1-27), the second one to works of religious nature (ff. 28-149), the third one contains profane authors. Textual-critical analysis allows us to situate some of the anthologies included in Neap. II C 32 within the main manuscript tradition of the authors.

La diarrhée épidémique porcine (DEP) est apparue en Europe à la fin des années 1970 et est causée par un alpha-coronavirus appelé virus de la diarrhée épidémique porcine (PEDV). Des épizooties sévères ont été rapportées en Asie à partir de 2010 et en Amérique à partir de 2013. Deux génotypes de souches de PEDV, se différenciant par des insertions/délétions dans le gène S, ont été isolés et circulent toujours actuellement dans ces régions. Ils regroupent d’une part les souches « S-InDel » présentes sur tous les continents, notamment en Europe y compris la France, et d’autre part les souches « S-non-InDel » hautement virulentes qui circulent en Asie et sur le continent américain uniquement. Les porcs infectés par le PEDV sont sujets à d’importantes diarrhées aqueuses ainsi qu’à des vomissements parfois accompagnés de signes de déshydratation. Les conséquences de la maladie sont d’autant plus importantes en cas d’infection par une souche « S-non-InDel » avec une mortalité pouvant atteindrLa pathogénicité comparée de deux souches de PEDV a été étudiée dans le cadre de cette thèse : une souche « S-non-InDel » isolée aux Etats-Unis en 2014 et une souche « S-InDel » isolée en France la même année. L’étude de la pathogénicité comparée a consisté à étudier les caractéristiques de transmission horizontale et les conséquences cliniques de l’infection en conditions expérimentales. En outre, l’excrétion dans la semence de ces deux souches a également été explorée. La dernière partie du projet de thèse était consacrée à l’étude des interactions du virus avec l’intestin ainsi que l’immu / Porcine epidemic diarrhea (PED) appeared in Europe at the end of 1970s and is caused by an alpha-coronavirus named porcine epidemic diarrhea virus (PEDV). Severe PED epizootic cases have been reported in Asia from 2010 and in America from 2013. Two genotypes of PEDV strains, differing by insertions/deletions in the S gene, have been described and circulating to date. The first genotype is represented by « S-InDel » strains group present on all continents among which Europe, including France. The second one is represented by the so-called highly virulent « S-non-InDel » strains which circulate in Asia and America only. The pigs infected by PEDV are affected by important aqueous diarrheas and sometimes vomiting accompanied by signs of dehydration. The consequences of the disease are more important in case of infection by an « S-non-InDel » strain with a mortality rate that could reach 100 % in suckling piglets.Uncertainties remained on pathogenicity differences according to the strains of PEDV and on impacts of a potential introduction of « S-non-InDel » PEDV strain in France. This thesis aimed at studying and comparing the pathogenicity of two strains of PEDV, an « S-non-InDel » PEDV strain isolated in the United-States in 2014 and an « S-InDel » PEDV strain isolated in France the same year. To compare pathogenicity between strains, the horizontal transmission and the clinical consequences of the infection in experimental conditions have been studied. Moreover the virus shedding in semen was also explored for the two strains. The last part of the project of the thesis was