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A GIS-Centric Approach for Modeling Vessel Management Behavior System Data to Determine Oyster Vessel Behavior on Public Oyster Grounds in LouisianaGallegos, David X 18 December 2014 (has links)
The satellite communications system called the Vessel Management System was used to provide geospatial data on oyster fishing over the nearly 1.7 million acres of the public water bottoms in Louisiana. An algorithm to analyze the data was developed in order to model vessel behaviors including docked, gearing, fishing and traveling. Vessel speeds were calculated via the Haversine formula at small and large intervals and compared to derive a measure of linearity. The algorithm was implemented into software using Python and inserted into a PostgreSQL database supporting geospatial information. Queries were developed to obtain reports on vessel activities and daily effort expended per behavior. ArcGIS was used to display and interpret the patterns produced by the vessel activity, yielding information about fishing activity clusters and effort which implied the location and productiveness of oyster reefs.
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The host rock succession of the Hornträskmassive sulfide deposit in the Rävliden orehorizon, Skellefte District, SwedenFriedrichs, Heiko January 2017 (has links)
No description available.
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On the modeling disrupted networks using dynamic traffic assignmentLiu, Ruoyu, active 2013 20 November 2013 (has links)
A traffic network can be disrupted by work zones and incidents. Calculating diversion rate is a core issue for estimating demand changes, which is needed to select a suitable work zone configuration and work schedule. An urban network can provide multiple alternative routes, so traffic assignment is the best tool to analyze diversion rates on network level and the local level. Compared with the results from static traffic assignment, dynamic traffic assignment predicts a higher network diversion rate in the morning peak period and off-peak period, a lower local diversion rate in the morning peak period. Additionally, travelers may benefit from knowing real-time traffic condition to avoid the traffic incident areas. Deploying variable message signs (VMSs) is one possible solution. One key issue is optimizing locations of VMSs. A planning model is created to solve the problem. The objective is minimize total system travel time. The link transmission model is used to evaluate the performance of the network, and bounded rational behavior is used to represent drivers' response to VMSs. A self-adapting genetic algorithm (GA) is formulated to solve the problem. This model selects the best locations to provide VMSs, typically places are that allow travelers to switch to alternative routes. Results show that adding more VMSs beyond a certain threshold level does not further reduce travel time. / text
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Modèles variationnels dynamique et hybride pour la simulation numérique d'écoulements turbulents / Dynamic and hybrid variational models for the simulation of turbulent flowsMoussaed, Carine 18 December 2013 (has links)
Ce travail est une contribution à la simulation numérique d'écoulements turbulents dans un but d'application industrielle. Nous nous intéressons dans un premier temps à une nouvelle combinaison "VMS-LES/procédure dynamique" pour la simulation d'écoulements autour de cylindres circulaire et carré. L'approche VMS-LES mise en œuvre a pour originalité d'utiliser une procédure de moyennage sur des volumes finis agglomérés dans le but de séparer les échelles, l'approche dynamique étant celle introduite par Germano en LES. Une approche hybride RANS/VMS-LES est ensuite évaluée sur le problème du cylindre circulaire à des nombres de Reynolds élevés. Cette approche introduit un paramètre d'hybridation qui selon la résolution locale de grille privilège le modèle RANS ou celui VMS-LES. Enfin, les performances d'un algorithme de Schwarz deux-niveau, qui utilise les méthodes de déflation et de balancing, sont examinées d'un point de vue efficacité et scalabilité dans le cas de simulations VMS-LES. / This work is a contribution to the numerical simulation of turbulent flows with the aim of industrial application. At first, we focus on a new combination "VMS-LES/dynamic procedure" for the simulation of flows around circular and square cylinders. The VMS-LES approach adopted in this work is original in using an averaging procedure over agglomerated finite volumes in order to separate the scales, the dynamic approach being the one introduced by Germano in LES. A RANS/VMS-LES hybrid approach is then evaluated on the circular cylinder test case at high Reynolds numbers. This approach introduces a hybridization parameter which privileges the RANS model or the VMS-LES model according to the grid resolution. Finally, the performance of a two-level Schwarz algorithm, which uses the deflation and balancing methods, are examined in terms of efficiency and scalability in the context of VMS-LES simulations.
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Telekrigsbibliotek en nationell angelägenhet? / - 2 - Electronic Warfare libararies A national affair?Söderman Carlsson, Urban January 2012 (has links)
Swedish Armed Forces are according to their development planning process taking actions to establish a new joint unit (SWEWOSE), with electronic warfare capability. SWEWOSÉ S main task will be designated to produce electronic warfare libraries for electronic warfare systems within the armed forces. The unit shall have capability to support with libraries in any state of conflict situation even if the supported unit with library needs conducting operations abroad. This essay examines the requirements that justify the establishment of a new unit in times when the armed forces conducting reorganizations and cutbacks in both economy and personnel. The possibilities to buy complete system solutions from an external supplier are examined. But also what kind of library support model that is to prefer according to the demands that the Swedish Armed Forces desired, in terms of capability in platform protection and battle space awareness. The results show that the demands that the Swedish Armed Forces has decided, best will be ful-filled and justified by a national electronic warfare unit, with library production as a main task.
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Evaluation of the Effectiveness of a Variable Advisory Speed System on Queue Mitigation in Work ZonesWilson, Aaron B. 10 March 2011 (has links) (PDF)
Construction is increasing due to increased demand and degradation of existing infrastructure. This construction often results in a reduced number of traffic lanes or lane width during construction, which often creates queue at the entrance to work zones. Variable Advisory Speed Systems (VASS) provide drivers with advanced warning regarding traffic speeds downstream to help them make better decisions in advance of problems that may exist downstream. The purpose of this study was to evaluate the effectiveness of a VASS at mitigating queues in work zone entrances during peak hour conditions. It was anticipated that by implementing a VASS queues would be reduced and vehicle flow increased in work zone areas. Three objectives of this study were: (1) research VASS systems that are available to be tested, (2) select and deploy a VASS in Utah at a long-term work zone, and (3) perform a statistical analysis on traffic flow characteristic data to evaluate the effectiveness of the VASS on queue mitigation. A literature review on the use of VASS for work zones returned minimal studies on advisory speeds in work zones. Most of the advanced speed notification systems, found during the literature review, used variable speed limit (VSL) applications. A VASS was selected and deployed at the northbound approach to the I-15 Beck St. widening project in North Salt Lake City. In this study the VASS consisted of five sensors and two variable message signs (VMSs). To determine if the system was effective at reducing queue the speed data were analyzed in detail to come to statistical conclusions. The collected data shows that the VASS investigated was effective on weekends during evening peak hours when there was a slow down. No consistent significance was seen on week days during the evening peak. There was no statistical difference between before and after speed data on any day of the week when there was no slow down. This study is valuable because it is unique in studying an advisory speed using VMSs and other ITS technology. This study recommends that further studies be conducted without a movable median barrier system, as was used in this construction project, to evaluate further about the effectiveness of VASSs. It is recommended that, if a VASS is considered, studies be done to see whether queues are expected to form at the work zone entrance, as VASSs will not be effective if queues do not form.
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Evaluating The Impact Of Oocea S Dynamic Message Signs (dms) On Travelers Experience Using The Pre-deployment SurveyRogers, John Hill 01 January 2007 (has links)
The purpose of this thesis was to evaluate the impact of dynamic message signs (DMS) on the Orlando-Orange County Expressway Authority (OOCEA) toll road network using the Pre-Deployment DMS Survey (henceforth referred to as "pre-deployment survey"). DMS are electronic traffic signs used on roadways to give travelers information about travel times, traffic congestion, accidents, disabled vehicles, AMBER alerts, and special events. The particular DMS referred to in this study are large rectangular signs installed over the travel lanes and these are not the portable trailer mount signs. The OOCEA is currently in the process of adding several fixed DMS on their toll road network. Between January 2007 and February 2008, approximately 30 DMS are planned on their network. It is important to note that there was one DMS sign on the OOCEA network before this study started. Since most of the travelers on OOCEA toll roads are from Orange, Osceola and Seminole counties, this study is limited to these counties. This thesis documents the results of pre-deployment analysis. The instrument used to analyze the travelers' perception of DMS was a survey that utilized computer aided telephone interviews. The pre-deployment survey was conducted during early November of 2006. Questions pertaining to the acknowledgement of DMS on the OOCEA toll roads, satisfaction with travel information provided on the network, formatting of the messages, satisfaction with different types of messages, diversion questions (Revealed and Stated preferences), and classification/socioeconomic questions (such as age, education, most used toll road, and county of residence) were asked to the respondents. The results of the pre-deployment analysis showed that 54.4% of the OOCEA travelers recalled seeing DMS on the network. The respondents commonly agreed that the DMS are helpful for providing information about hazardous conditions, and that the DMS are easy to read. The majority of the travelers preferred DMS formats as a steady message for normal traffic conditions, and use of commonly recognized abbreviations such as I-Drive for International Drive. The results from the binary logit model for "satisfaction with travel information provided on OOCEA toll road network" display the significant variables that explain the likelihood of the traveler being satisfied. The results from the coefficients show that infrequent travelers are more likely to be satisfied with traveler information on OOCEA toll roads. In addition, the provision of hazard warnings, special event information, and accuracy of information on DMS are associated with higher levels of satisfaction with traveler information. The binary logit model for "Revealed Preference (RP)" diversion behavior showed that Seminole County travelers were likely to stay on the toll road, and SR 408 travelers were likely to divert off the toll road. The travelers who acknowledged DMS on the OOCEA network were also likely to divert off the toll road, but those who learned of the congestion by DMS were likely to stay on the toll road. Learning of congestion by DMS could encourage travelers to stay, since when they are on the toll roads, diversion at times could be difficult with no access to exits or little knowledge of alternate routes. But it is also possible that travelers stayed because their perception was that the toll roads are faster, especially when messages on DMS show travel times that confirm the travelers' belief. Travelers who were not satisfied with travel information on the network were more likely to divert off the toll road. The implications for implementation of these results are discussed in this thesis. DMS should be formatted as a steady message for normal traffic conditions. Commonly recognized abbreviations, such as I-Drive for International Drive, must be used for roadway identification when possible. DMS messages should be pertained to information on roadway hazards when necessary because it was found that travelers find it important to be informed on events that are related to their personal safety. Accuracy of information provided on DMS was important for traveler information satisfaction because if the travelers observe inaccurate travel times on DMS, they may not trust the validity of future messages. DMS information that led to the travelers canceling their intended stops led to a higher likelihood of them being dissatisfied with traveler information. It is important to meet the travelers' preferences and concerns for DMS.
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Simulation numérique aéroacoustique d'écoulements par une approche LES d'ordre élevé en éléments finis non structurésYser, Pierre 26 January 2017 (has links)
Cette thèse vise à améliorer la précision numérique des simulations aéroacoustiques d’écoulements dans un contexte précis, celui du cadre industriel avec un partenariat Dassault Aviation. Pour répondre à cette problématique, la modélisation aux grandes échelles est utilisée afin de la rendre plus efficace et adaptée à la méthode numérique des éléments finis stabilisée par SUPG/GLS. Afin de préciser la méthode numérique, une première partie est consacrée à la formulation théorique et pratique du code AETHER utilisé. La précision des schémas numériques spatial et temporel est aussi présentée. L’idéologie principale issue de la famille des modèles Variational Multi-Scale a été retenue afin de construire le nouveau modèle de sous-maille. En effet, une précédente thèse avait démontré la pertinence de ce type d’approche pour les éléments finis. Même si le cadre est applicatif, cette thèse propose une réflexion générale sur le filtrage numérique en éléments finis ainsi qu’un nouveau procédé pour filtrer le plus efficacement l’écoulement calculé. Cette nouvelle approche de filtrage est particulièrement bien adaptée aux éléments finis et à la montée en ordre spatial. Un modèle hybride de gestion des parois est aussi développé afin de pouvoir utiliser le nouveau modèle de sous-maille dans des configurations complexes comprenant des surfaces solides. Le processus de filtrage est testé sur le cas académique des tourbillons de Taylor-Green et présente un réel gain. Enfin le modèle global est utilisé pour calculer une configuration industrielle de tri-corps hypersustenté nommée LEISA II. Grâce au nouveau modèle proposé et validé par les résultats expérimentaux, il a été possible de fournir des interprétations physiques pointues sur le comportement complexe de l’écoulement du bec et du bruit qu’il génère. Cette dernière partie est une illustration pertinente de l’utilisation des modèles aux grandes échelles pourtant coûteux, et cela même dans un contexte industriel. / The goal of this thesis is to improve the numerical accuracy for aeroacoustic flow simulations in a given scope, that is an industrial application for a partnership with the aircraft company Dassault Aviation. These works are then looking for a new large eddy simulation (LES) model which is efficient and well suited for the finite element formulation and the SUPG/GLS stabilisation method. In order to clarify the scientific environment and numerical tools, a first part is devoted to the theoretical and practical framework of the AETHER code. The spatial and temporal performances of its numerical schemes are assessed too. The philosophy of the Variational Multi-scale models has been selected to build an improvement for the new subgrid model. Indeed, a previous thesis had already demonstrated the relevance of this kind of models especially for the finite element method. Despite the industrial framework, a general reflection on the numerical filtering in finite elements is suggested and a new filtering process is developed in order to sort efficiently the scales of the simulated flow. This new filtering method is especially well fitted to finite element simulations and the high spatial order schemes. An hybrid model has been developed too in order to be able to use the new VMS model in complex configurations involving solid bodies. The filtering process is assessed on an academic case called Taylor-Green vortices and shows a real benefit compare to classical approaches. Finally the whole model is used to compute an industrial configuration, a three-element high-lift device called LEISA II. Thank to the validation of the new model with the experimental results, it has been possible to find accurate explanations about the complex flow behaviour of the slat and its noise generation. This last part is a relevant demonstration of the LES models use in the industrial world even if they are still costly in computation ressources.
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Prospecção geoquímica: estaurolita, ilmenita e magnetita como minerais traçadores para depósitos do tipo VMS / Chemistry prospection: staurolite, ilmenite, magnetite guide minerals for VMS depositsDiana Magalhães Cunha Rodrigues 29 September 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Conselho Nacional de Desenvolvimento Científico e Tecnológico / A região de Itutinga foi alvo de estudos prospectivos por parte da empresa BP mineração na década de 80, onde foram encontradas mineralizações em lentes de sulfetos metálicos (Zn-Cu-Ag-Fe) associados a rochas komatiíticas peridotíticas e basaltos toleíticos (anfibolitos) do greenstone belts, nas proximidades da fazenda São Jerônimo, enquadrando-se em um depósito do tipo VMS. A partir destas informações encontradas na literatura propôs-se estudar a estaurolita, a magnetita e a ilmenita para, a partir da determinação do seu conteúdo em zinco, indicar a aplicabilidade destes três minerais como traçadores desses tipos de depósitos. Para isso foram coletadas amostras de sedimentos de corrente e concentrados de batéia na região próxima à ocorrência, no entorno da cidade de Itutinga, e também em uma região próxima a cidade de Itumirim, já que existem semelhanças litológicas entre as duas áreas. Os sedimentos de corrente, as frações magnéticas e as frações de 0,3A (separador eletromagnético Frantz) foram enviados para análises químicas por absorção atômica e ICP-OES. Os concentrados de batéia foram descritos, separando-se cristais de estaurolita de cada amostra coletada, e analisando-os em MEV-EDS para determinação da química mineral. Os resultados dos sedimentos de corrente apontaram que os pontos da fazenda São Jerônimo (ME-03, Itutinga 51,7 ppm de Zn) e o ponto do Ribeirão Santa Cruz, (ME-06, Itumirim 36,1 ppm de Zn) foram os que apresentaram melhores resultados, indicando anomalias em zinco nas duas áreas estudadas . As estaurolitas, retiradas dos concentrados de batéia de cada ponto estudado, foram divididas em três conjuntos, de acordo com os teores de ZnO encontrados: 1 - entre 2,96% e 3,25% de ZnO em peso; 2 - entre 2,03% e 2,76% de ZnO em peso; 3 - < 1,67% de ZnO em peso, sendo comparável com outras estaurolitas encontradas em diversos depósitos de Zn do mundo, como Dry River, Austrália e Palmeirópolis Goiás. Assim, as estaurolitas apresentam bons resultados como minerais indicadores na área estudada. Em relação as magnetitas e ilmenitas estudadas, o número de amostras coletadas no presente estudo foram muito pequenas para se ter informações conclusivas sobre o papel destes minerais como traçadores. Por outro lado, os resultados das análises químicas nos concentrados de ilmenita (até 856 ppm de Zn) e nos concentrados de magnetita (até 216 ppm de Zn), indicam a disponibilidade deste metal nas áreas estudadas. Assim, é possível se detectar a presença do zinco por dois meios: através de sedimentos de corrente, através de halos de dispersão química do elemento zinco, e através dos minerais resistatos (estaurolita zincífera, magnetita e ilmenita), a partir de uma dispersão clástica do grão. / The Itutinga region was studied for BP mineration in 80s , where they found sulphide mineralization in lenses (Zn-Cu-Ag-Fe) associated with komatiitic peridotite rocks and tholeitic basalts (amphibolites) of greenstone belts, near of Fazenda São Jerônimo. With this information in the literature the propose is study the staurolite, magnetite and ilmenite for indicating the applicability of these three minerals as tracers of these types of mineralization. For this, samples of stream sediment and panning concentrates in the region near the city of Itutinga, and also in a region near the city of Itumirim. The stream current, magnetic fractions and ilmenite fractions were sent to chemistry analyses (Atomic absorption and ICP-OES), and the panning concentrates were analyzed for the separating of staurolite crystals, and sent to SEM-EDS. The stream sediments results showed that the point of Fazenda São Jerônimo (ME-03, Itutinga 51,7 ppm of Zn) and the point of Ribeirão Santa Cruz (ME-06, Itumirim 36,1 ppm of Zn) were presented the best result. The staurolite of panning concentrates were divided into three groups according to levels of ZnO matched: 1 - between 2.96% and 3.25% by weight of ZnO, 2 - from 2, 03% and 2.76% by weight of ZnO, 3 - <1.67% ZnO by weight, comparable with other staurolite found in many zinc deposits in the world, such as Dry River, Australia and Palmeirópolis Goiás. Thus, the staurolite show good results as indicator minerals in the area. With respect to magnetite and ilmenite concentrates, the number of samples collected in both areas was too small to have conclusive information. On the other hand, the results of the chemical ilmenite (up to 856 ppm Zn) and magnetite (up to 216 ppm Zn), indicate the availability of this metal in the areas studied. Thus, it is possible to detect the presence of zinc by two means: through stream sediments through chemical dispersion halos of zinc, minerals and through resistive minerals (zincian staurolite, magnetite and ilmenite), from a crystal clastic dispersion.
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Les pêcheries pélagiques de la ZEE mauritanienne : nouvelles méthodes pour de nouvelles connaissances / Pelagic fisheries in the Mauritanian EEZ : New methods for new insightsIsselmou Braham Braham, Cheikh Baye 26 November 2013 (has links)
Les contextes national et international sont marqués par une prise de conscience de plus en plus grande de l’importance du poisson pour la sécurité alimentaire des populations des pays sous-développés. En Mauritanie, les petits pélagiques constituent une source de protéines animales accessibles aux faibles pouvoirs d’achat et contribuent à garantir la sécurité alimentaire de nombreuses populations. Malgré la présence d’une variabilité naturelle importante des espèces pélagiques, ce travail de thèse montre qu’il existe des éléments de stabilité dans l’écosystème pélagique dans la zone nord-ouest africaine. L’hypothèse de la présence des stocks sédentaires au niveau des zones de nourriceries en Mauritanie et au Sénégal est démontrée. La répartition spatio-temporelle des sardinelles en relation avec la dynamique de l’océan (upwelling, température de surface et chlorophylle) a été examinée. L’analyse des statistiques de la pêche sur une série de plus de trente (30) ans ne soutiennent pas l’immigration en provenance du Sénégal vers la Mauritanie d'Avril à Septembre selon l’hypothèse de Boëly (1978). Ce travail de thèse examine des hypothèses de migrations possibles des sardinelles dans la zone nord-ouest africaine et d’importantes implications en matière de gestion sont discutées. Pour finir, ce travail est replacé dans son contexte plus global de l’aménagement de la pêcherie des petits pélagiques. De nouvelles perspectives pour l’application des techniques géostatistiques (indicatrices et co-krigeage) et modélisation statistique sont envisagées pour l’étude de la dynamique des stocks des sardinelles et chinchards. / National and international context marked by an awareness of growing importance of pelagic fish for food security of people in underdeveloped countries . The depletion of demersal species also makes this extremely important resource for the future pelagic fisheries in Mauritania. Mauritanian EEZ is characterized by the existence of a favorable development of several species hydro-climatic and morphological phenomena , small pelagic species that represent more than 90% of the fisheries potential is about one million tones. The major problems facing the management of these species is understanding the roles played by them in their biogeography intrinsic spatio- temporal dynamics ( short-lived , aggregation , etc. ..) and the evaluation of their abundances . Assessment of exploited fish stocks is a priority. However, the recurring difficulty of evaluations of these fisheries, naturally very unstable, often reflected a lack of precision in the methods used , the incompleteness of the data ( which is also a problem of sampling) or sampling uncontrolled .The Mauritanian small pelagic fisheries are multi-species (sardines , horse mackerel , sardinella ) . In addition to the data provided by the logbooks including the holding is mandatory for industrial units, survey data for the landing craft and coastal segment often used to calculate the abundance, acoustic surveys , are an important means for quantify the abundance and study the distribution of these resources. The data collected by observers on board fishing industrial units are also a source of important information.Based on these data , this work aims at the reconstruction of the main series of abundances of small pelagic stocks in the northern part of West Africa , to be used in the adjustment of stock assessments models. Given the importance of the environmental component in very large fluctuations observed, the integration of this dimension in the analysis of this series catches the role of each of these factors (fisheries and environment) in the variability of abundance seasonal and amplitude of their migration.In addition to these conventional data Mauritania introduced on board commercial fishing vessels with VMS . This system allows the transmission by satellite to the body control the ship's position every hour is an important technological advance. This new type of data could therefore be a new source for estimating abundance and fishing effort of small pelagic species through appropriate statistical methods. A method for the interpretation in terms of paths abundance index was applied. The coupling of VMS and logbook will help to improve the definition of nominal fishing effort and catch location at fine spatial and temporal.The general problem is how to improve the estimation of the abundance of small pelagic stocks , understand fluctuations in the abundance and migration strategy of the species as well as tactics and strategies implemented by fleets to fish resources whose behavior is often erratic . It is therefore to adresse several issues in particular:What is the trend of the evolution of the abundance of pelagic species in the North West African area? The interpretation of the trajectories in terms of VMS fishing can it be used to map the abundance of key species? What are the seasons abundances? Environmental parameters they play an important role on the distribution of species? Will there a difference between tactics and strategies of the different fleets fishing for small pelagic? Data logs and data collected by observers on board can be used as a priori knowledge? To address these issues , we proceed to the mobilization of all relevant time series and implement innovative statistical and geostatistical methods , some of which applied for the first time in the sub -region for these stocks.
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