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Evaluation of cost estimating methods for military software application in a COTS environmentGavin, Victor S. 23 February 2010 (has links)
<p>Due to changes in the economy, the Department of Defense is requiring
dramatic changes in its procurement process for major systems. These
changes attempt to leverage from the large quantity of commercial software
that is currently on the. market. As a result, better estimating techniques are
required to properly account for software reuse. For government agencies,
these techniques must be understood and applied when validating and
tracking contractor performance. An industry survey was performed and
subsequently two techniques were evaluated. The evaluation criteria used is
consistent with the attributes of the systems engineering process. This project
will evaluate the two most widely used; function point analysis and rule of
thumb analysis were selected for computing the cost of a specified software
intensive project.</p> / Master of Science
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Analyses of GIMMS NDVI Time Series in Kogi State, NigeriaKarrasch, Pierre, Wessollek, Christine, Palka, Jessica 06 September 2019 (has links)
The value of remote sensing data is particularly evident where an areal monitoring is needed to provide information on the earth's surface development. The use of temporal high resolution time series data allows for detecting short-term changes. In Kogi State in Nigeria different vegetation types can be found. As the major population in this region is living in rural communities with crop farming the existing vegetation is slowly being altered. The expansion of agricultural land causes loss of natural vegetation, especially in the regions close to the rivers which are suitable for crop production. With regard to these facts, two questions can be dealt with covering different aspects of the development of vegetation in the Kogi state, the determination and evaluation of the general development of the vegetation in the study area (trend estimation) and analyses on a short-term behavior of vegetation conditions, which can provide information about seasonal effects in vegetation development. For this purpose, the GIMMS-NDVI data set, provided by the NOAA, provides information on the normalized difference vegetation index (NDVI) in a geometric resolution of approx. 8 km. The temporal resolution of 15 days allows the already described analyses. For the presented analysis data for the period 1981-2012 (31 years) were used. The implemented work flow mainly applies methods of time series analysis. The results show that in addition to the classical seasonal development, artefacts of different vegetation periods (several NDVI maxima) can be found in the data. The trend component of the time series shows a consistently positive development in the entire study area considering the full investigation period of 31 years. However, the results also show that this development has not been continuous and a simple linear modeling of the NDVI increase is only possible to a limited extent. For this reason, the trend modeling was extended by procedures for detecting structural breaks in the time series.
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Statistical Inference for Change Points in High-Dimensional Offline and Online DataLi, Lingjun 07 April 2020 (has links)
No description available.
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Information Approach to Change Point Analysis and its Application to Fiscally Standardized CitiesHadamuscin, Larry A. 12 August 2022 (has links)
No description available.
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Funkcinių taškų analizės metodų tyrimas / Function point analysis methods researchGervė, Šarūnas 09 July 2011 (has links)
Kad sugebėtume efektyviai valdyti programinės įrangos kūrimą, mes turime sugebėti matuoti programinę įrangą. Alan Albrecht 1979 metais IBM korporacijoje pasiūlė naudoti funkcinių taškų analizės metodą. Šis metodas matuoja programinės įrangos naudotojui suteikiamą funkcionalumą ir yra nepriklausomas nuo naudojamų programinės įrangos kūrimo technologijų. Šiuo metu yra jau 5 standartizuoti funkcinių taškų analizės metodai, kurie naudoja skirtingas taisykles programinės įrangos dydžio matavimui. Šiame darbe yra apibrėžiami vertinimo kriterijai ir pagal juos lyginami standartizuoti IFPUG, Mark II, COSMIC, NESMA ir FiSMA funkcinių taškų analizės metodai. Lyginant metodus yra nagrinėjami jų koncepciniai panašumai ir skirtumai, standartizuotumas, industrinių duomenų prieinamumas, konvertuojamumas, tinkamiausia taikymo fazė, matavimo taisyklių subjektyvumas, nefunkcinių naudotojų reikalavimų vertinimas, sertifikavimo ir skaičiavimo vadovų prieinamumas, metodus palaikantys programiniai įrankiai bei metodų taikymo sritis. Analizės rezultatai parodo, kad šiuo metu geriausia yra pasirinkti IFPUG arba COSMIC metodus. / To effectively manage software development we must be able to measure software. Alan Albrecht in IBM Corporation in 1979 proposed the use of function point analysis method. This method measures functionality provided to the user by the software and is independent of the used software development technology. There are currently 5 standardized function point analysis methods, which use different rules for software size measurement. In this work estimation criteria are defined and used to compare standardized IFPUG, Mark II, COSMIC, NESMA and FiSMA function point analysis methods. During the comparison of methods their conceptual similarities and differences, standardization, availability of industry data, convertibility, the most suitable usage phase, subjectivity of measurement rules, estimation of non-functional user requirements, availability of certification and counting practices manuals, supporting software tools and the scope of methods applicability are examined. The analysis results show that the best choice is IFPUG or COSMIC methods.
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人口流動模型的距離效應之探討 / A distance-based modification of spatial interaction model in modelling population movement梁穎誼, Leong, Yin Yee Unknown Date (has links)
人口流動具有各種型態。其中包含了遷移、移動、以及通勤人口。在宏觀模型框架下,空間互動模型(簡稱SIM)對於測量人口流動扮演了重要的角色。距離遞減效應為空間互動模型中重要的因子。該效應描述了人口流動的頻率會隨著移動距離而逐漸下降。然而,從實證上,本研究發現人口流動與移動距離的函數,並非在距離上保有恆定的關係。
在本文中,我們提出了對此非恆定的距離遞減效應之修正方法。本修正法運用了轉折點模型的特點,套入了空間互動模型的距離函數上。本文首先運用了電腦模擬驗證了此方法的穩定性與有效性。接下來,研究將此方法應用在兩個人口流動資料。第一個是從台灣健保資料庫觀察出的民眾就醫地變化。健保資料庫包含了總人口的5%抽樣資料。由於在抽樣上瑕疵不大,因此健保抽樣資料具有了一定的代表性。第二個資料則是英國統計局所提供的人口遷移普查資料。在這兩個資料上,我們發現本研究所提修正法,相較於傳統的空間互動模型具有更好的模型配適表現。此改善程度在非都市地區尤其更為明顯。 / Population movement encompasses various forms, such as migration, mobility, and commuting. Spatial Interaction Model (SIM) serves as an important tool to calibrate these movements in the sense of macro modelling. One of the important features of this model is that the number of migrants often decays with the distance. However, we found that this is not always the case in practice and the decay pattern may change with distance.
In this study, we propose a distanced-based modification to the SIM, via applying the techniques of change-point problem to construct distance functional form. Computer simulation is illustrated to validate the method and the empirical analysis of flow data from Taiwan’s National Health Insurance Research Database (NHIRD), and also England & Wales internal migration data also provides sound evidences to support the proposed approach. Note that the flow data from the NHIRD consists of a sample of about one million people and can be treated as a fine sample representative of Taiwan’s whole population (about 23 million people). Our results show that the modified approach is more adequate than the traditional SIM, especially for describing the movements of suburban areas in Taiwan.
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Evaluation de performances sur le standard IEEE802.16e WiMAX / IEEE802.16e standart - Mobile WiMAX -Performances EvaluationsPeyre, Thierry 09 December 2008 (has links)
Les dernières décennies ont connu l’apogée des transmissions hertziennes, et celles à venir connaîtront incontestablement le développement et le déploiement intense de systèmes de communications sans-fil. Dès à présent, il est possible de communiquer par onde sur petite et très petite distance (LAN et PAN). Les populations se sont familiariséesavec les interfaces bluetooth (IEEE802.15) présentes dans la majorité des objetscommuniquant (ordinateur portable, téléphone, PDA, etc...). Les foyers s’équipentmaintenant facilement et à bas prix d’interfaceWi-Fi (IEEE802.11), afin de profiter d’uneutilisation nomade de leur accès internet. Ainsi, la forte croissance dumarché des offresinternet combinée avec celle du marché des téléphones mobiles ont habitués un large spectre d’utilisateurs à communiquer sans fil. Ce contexte sociologique et financier encourage donc l’arrivée de solutions nouvelles répondant à des besoins latents. Parmi ceux-là, le marché met en évidence le manque de système de communication sur moyenne distance (MAN). Les réseaux ad-hoc peuvent répondre à ce genre de besoin. Mais àce jour, les performances sont trop faibles pour les besoins des utilisateurs et elles dépendenttrop fortement de la densité desmachines nomades. Aussi, le consortiumIEEEcherche au travers de sa norme IEEE802.16 à fournir un système complet de communicationsans-fil sur moyenne distance (MAN). Appelé aussiWiMAX, ce système se basesur une architecture composée d’une station de base (BS) et de nombreux mobiles utilisateurs(SS). Le standard IEEE802.16 définit les caractéristiques de la couche physiqueet de la couche MAC. Il décrit l’ensemble des interactions et événements pouvant avoirlieu entre la station de base et les stations mobiles. Enfin, le standard fournit différents paramètres et variables servant aux mécanismes de communication. Comme tout nouveau standard émergeant, la norme IEEE802.16 ne profite pas d’un état de l’art aussi développé que celui du IEEE802.11 par exemple. Aussi, de nombreuses études et idées sont à développer.En premier lieu, nous effectuons un large rappel de la norme WiMAX et en particulier le IEEE802.16e. Associé à cela, nous dressons un état de l’art des travaux traitant des aspects et perspectives liés au sujet de notre étude.Par la suite, nous proposons un modèle novateur de performance des communicationsIEEE802.16e. Au travers de ce modèle, nous développons une étude générale et exhaustive des principaux paramètres de communication. L’étude explicite l’impact deces paramètres ainsi que l’influence de leur évolutions possibles. De cela, nous critiquonsla pertinence de chacun d’eux en proposant des alternatives de configurations.5En sus, nous proposons un mécanisme novateur favorisant le respect de qualité de service(QoS) sur couche AC.Nous développons un principe original d’établissement de connexion favorisant l’accès aux communications sensibles aux délais de transmission.Dans une dernière partie, nous déterminons la capacité d’un système IEEE802.16 à gérer les arrivées et départs des utilisateurs. Tout en y associant une étude de performance d’un nouvel algorithme de contrôle d’admission. Cet algorithme d’admission vise à remplir des objectifs multiples : empêcher les famines de ressources sur les trafics les moins prioritaires, favoriser l’admission des utilisateurs en maintenant une gestion optimale de la ressource radio. Notre étude aboutit à une modélisation et une critique des variations de paramètre associés à ce nouvel algorithme. Nous y intégrons par la suite le principe de mobilité où les utilisateurs ont la capacité de se mouvoir au sein d’une cellule. Cette intégration se fait en y associant des mécanismes originaux afin d’assurer la pérennité du service aux utilisateurs mobiles. / The last decade witnessed the peak of the hertzian communications. The following ones will undoubtedly testify the intensive deployment and the development of all wireless ways of transmission. Due to cheaper equipments, the people are now used with all sorts of connected objects : laptop, smartphone, pad, and more recently, Connected Video display and audio diffusers. All these stuffs allow to keep an access to internet, even in a nomad use. This economical and sociological context promotes the emerging of new solutions metting latent needs by offering better performances. Consumer studies highlight particularly the lack of transmissions solution for Metropolitan Area Networks (MAN). Ad-hoc wireless solutions lead to satisfy the MAN needs, but the throughput is too importantly related to the ad-hoc customer capacity and density over the MAN coverage.The IEEE consortium seeks, through its IEEE802.16e standart, to provide a wireless transmission technology specifically design for the middle range network. Knowed as WiMAX, this system are based on a point to multipoint architecture. WiMAX standart gathers Base Station (BS) and Subscriber Stations (SS), and defines for both the Physical and MAC layer in the OSI Model. In addition, the standart proposes a set of default parameters for the two first OSI Layers.As any emerging standart, the IEEE802.16e suffers form a lack of litterature (works, studies and enhancement proposals). More studies are explicitly needed to craft and tune the IEEE802.16e standart in order to better answer to the specific issues met in the actual context of transmission.In a first step, we present in a large scale the IEEE802.16e standart specifications. In addition we highlight the main state of art linked to this subject.Second, we propose an original performance model, the first one that takes in account all the MAC layer parameters of the standart. Based on this model, we lead a general and exhaustive performance study of each communication parameters. This study highlights the importance of each parameters and propose some enhancements in fonction of the type of Quality of Service (QoS). In addition, we introduce an call engaging mecanism which respects the QoS on the MAC layer.In a last part, we compute the IEEE802.16e capacity to manage the incoming and leaving calls. we perform this study by introducing a new Connection Admission Control (CAC). The CAC algorithm achieves sevral objectives : prevent from the lack of ressource for the lowest priority flows as well as optimize the radio resource consumption to facilitate the access for the users. Our study is concluded by proposing an new capacity model and algorithm for the CAC. Moreover, this last proposal prevents the call drop due to user mobility.
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Constru????o e valida????o de um instrumento para contratar a terceiriza????o de desenvolvimento de sistemas utilizando pontos de fun????o como moedaRinaldi, Hilda Marina da Rocha 10 October 2003 (has links)
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Previous issue date: 2003-10-10 / The purpose of this research was to obtain an adequate hiring process for the systems development outsourcing, to obtain a fair precification for the job, through a more precise quantification of the necessary efforts involved, aiming to avoid constant pricing reviews coming from changes in the efforts forecasted at thebeginning. The research's key point was the building of an instrument allowing the perfect identification of most expressive issues to be outlined in a request for system development, then making contracts handling a routine in accordance with international standards. After reviewing many of the existing software metrics, the research led to the adequacy of the FPA (Function Point Analysis) in the contractors / users relationship handling, considering that it is internationally accepted for being an ISO regulation and it is in accordance with the requirements of another ISO regulation, regarding to Functional Size Measurement. One of the research's achievements was that the FPA use allows a better evaluation of the bids offered by suppliers, favoring an hiring with fair price and avoiding contract reviews that very often led to undesirable price reviews. Concerning to the methodology, 3 pre-tests were prepared using a small and selected sample constituted by professionals, in both developing systems and outsourcing areas. These professionals were skilled in metrics. Based on the pre-test results, a questionnaire was prepared, containing 16 questions to be answered by a group of professionals, with skills very alike of those in the pre-test answerers. Answers were given through marking one out of five alternatives according to Likert Scale. The resulting data were evaluated using the SPSS software, base 10.0 and analyzing 16 answers frequency. Both Factorial and Discriminant Analysis were used. To make the research more relevant, other statistical data were analyzed to verify the answerer's conditions, if contractor or user, and the impact of the time working in the system area and the job position in the answers. As result of the research, relevant issues to be considered in an outsourcing contract could be observed, being the main one the existence of a metric to enhance transparency and objectivity involving contractors/users relationship and leading to the most adequate price. / O prop??sito desta pesquisa foi obter um processo adequado de terceiriza????o de contrata????o de desenvolvimento de sistemas, para resultar numa precifica????o mais justa do trabalho por meio de uma quantifica????o do esfor??o necess??rio envolvido, visando evitar revis??es constantes dos pre??os advindos de mudan??as no esfor??o previsto no in??cio do trabalho. O ponto focal da pesquisa foi a constru????o de um instrumento que possibilitasse identificar perfeitamente os mais significativos assuntos numa requisi????o de desenvolvimento de sistemas, tornando a gest??o de contratos uma rotina amparada em padr??es internacionais. Ap??s a an??lise de v??rias t??cnicas de medi????o de software existentes, a pesquisa concluiu que a An??lise de Pontos de Fun????o demonstrou ser a mais indicada para a gest??o das rela????es entre CONTRATANTES e CONTRATADAS, por se tratar de uma t??cnica aceita internacionalmente, ser uma norma ISO e estar em conformidade com outra norma ISO que considera o projeto para Medi????o Funcional de Software. Uma das resultantes da pesquisa foi que o uso da An??lise de Pontos de Fun????o possibilita uma melhor avalia????o das propostas apresentadas pelos fornecedores, favorecendo uma contrata????o por um pre??o mais equilibrado evitando revis??es de contratos que freq??entemente levam ?? indesej??veis revis??es de pre??os. De acordo com a metodologia foram realizados 3 pr??-testes com uma amostra selecionada constitu??da de profissionais atuantes em desenvolvimento de sistemas e em terceiriza????o e tamb??m com conhecimento de m??tricas de software. Baseado nos resultados do pr??-teste foi elaborado um instrumento com 16 assertivas para serem respondidas por um grupo de profissionais com habilidades bastante parecidas com as dos respondentes do pr??-teste. As respostas deveriam ser assinaladas por meio da escolha de uma entre cinco alternativas de acordo com a escala de Likert. Os dados resultantes foram analisados com apoio do software SPSS base 10.0 e verificadas as freq????ncias das 16 respostas. Tamb??m foram utilizados os m??todos de an??lise fatorial e de an??lise discriminante. Para tornar a pesquisa mais relevante, outros dados estat??sticos foram analisados para que se verificasse se as respostas aderiam ??s condi????es dos respondentes como CONTRATADA ou como CONTRATANTE e o impacto do tempo de experi??ncia na ??rea e o tipo de fun????o exercida. Como resultado da pesquisa foi observado que considera????es relevantes devem ser levadas em conta em um contrato de desenvolvimento de sistemas, sendo a principal delas a exist??ncia de uma m??trica, para que se tenha mais transpar??ncia e objetividade entre CONTRATANTE e CONTRATADA e que se pratique o pre??o mais adequado.
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Méthodes mathématiques et numériques pour la modélisation des déformations et l'analyse de texture. Applications en imagerie médicale / Mathematical and numerical methods for the modeling of deformations and image texture analysis. Applications in medical imagingChesseboeuf, Clément 23 November 2017 (has links)
Nous décrivons une procédure numérique pour le recalage d'IRM cérébrales 3D. Le problème d'appariement est abordé à travers la distinction usuelle entre le modèle de déformation et le critère d'appariement. Le modèle de déformation est celui de l'anatomie computationnelle, fondé sur un groupe de difféomorphismes engendrés en intégrant des champs de vecteurs. Le décalage entre les images est évalué en comparant les lignes de niveau de ces images, représentées par un courant différentiel dans le dual d'un espace de champs de vecteurs. Le critère d'appariement obtenu est non local et rapide à calculer. On se place dans l'ensemble des difféomorphismes pour rechercher une déformation reliant les deux images. Pour cela, on minimise le critère en suivant le principe de l'algorithme sous-optimal. L'efficacité de l'algorithme est renforcée par une description eulérienne et périodique du mouvement. L'algorithme est appliqué pour le recalage d'images IRM cérébrale 3d, la procédure numérique menant à ces résultats est intégralement décrite. Nos travaux concernent aussi l'analyse des propriétés de l'algorithme. Pour cela, nous avons simplifié l'équation représentant l'évolution de l'image et étudié l'équation simplifiée en utilisant la théorie des solutions de viscosité. Nous étudions aussi le problème de détection de rupture dans la variance d'un signal aléatoire gaussien. La spécificité de notre modèle vient du cadre infill, ce qui signifie que la distribution des données dépend de la taille de l'échantillon. L'estimateur de l'instant de rupture est défini comme le point maximisant une fonction de contraste. Nous étudions la convergence de cette fonction et ensuite la convergence de l'estimateur associé. L'application la plus directe concerne l'estimation de changement dans le paramètre de Hurst d'un mouvement brownien fractionnaire. L'estimateur dépend d'un paramètre p > 0 et nos résultats montrent qu'il peut être intéressant de choisir p < 2. / We present a numerical procedure for the matching of 3D MRI. The problem of image matching is addressed through the usual distinction between the deformation model and the matching criterion. The deformation model is based on the theory of computational anatomy and the set of deformations is a group of diffeomorphisms generated by integrating vector fields. The discrepancy between the two images is evaluated through comparisons of level lines represented by a differential current in the dual of a space of vector fields. This representation leads to a quickly computable non-local criterion. Then, the optimisation method is based on the minimization of the criterion following the idea of the so-called sub-optimal algorithm. We take advantage of the eulerian and periodical description of the algorithm to get an efficient numerical procedure. This algorithm can be used to deal with 3d MR images and numerical experiences are presented. In an other part, we focus on theoretical properties of the algorithm. We begin by simplifying the equation representing the evolution of the deformed image and we use the theory of viscosity solutions to study the simplified equation. The second issue we are interested in is the change-point estimation for a gaussian sequence with change in the variance parameter. The main feature of our model is that we work with infill data and the nature of the data can evolve jointly with the size of the sample. The usual approach suggests to introduce a contrast function and using the point of its maximum as a change-point estimator. We first get an information about the asymptotic fluctuations of the contrast function around its mean function. Then, we focus on the change-point estimator and more precisely on the convergence of this estimator. The most direct application concerns the detection of change in the Hurst parameter of a fractional brownian motion. The estimator depends on a parameter p > 0, generalizing the usual choice p = 2. We present some results illustrating the advantage of a parameter p < 2.
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ESTIMAÇÃO DE MÉTRICAS DE DESENVOLVIMENTO AUXILIADA POR REDES NEURAIS ARTIFICIAIS. / ESTEEM OF METRIC OF DEVELOPMENT ASSISTED FOR ARTIFICIAL NEURAL NETS.Fonseca Filho, José Raimundo dos Santos 14 April 2003 (has links)
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Previous issue date: 2003-04-14 / Several modeling approaches for the process of development in software engineering able of
subsidizing decision making in the management of project are being searched. Metric of
softwares, process modeling and estimation techniques have been independently considered
either taking into consideration the intrinsic characteristic of softwares or their constructive
process. This research proposes a complete, simple and efficient model for representing the
whole process of development which, based on a set of features of the process and basic
attributes of softwares, yields good estimation metrics (time and effort) of the development of
the software still at the beginning of the process. The model relates constructive
characteristics of the process to each type of organization, for identifying classes of
homogeneous behavior based on Kohonen Neural Network. Directly, from this classification,
according to the basic attributes of each software being developed, metrics may be estimated
supported by Feedforward Neural Networks. A prototype is specified in Unified Model
Language (UML) and implemented to estimate metrics for the development of softwares.
Comparisons of the obtained results with those available in literature are presented. / Diversas representações do processo de desenvolvimento na Engenharia de softwares capazes
de, eficientemente, subsidiar a tomada de decisões no gerenciamento de projetos, vêm sendo
arduamente pesquisadas. Métricas de softwares, modelos de processo e técnicas de estimação
têm sido propostos em grande quantidade, tanto devido a características intrínsecas dos
softwares quanto a características do próprio processo construtivo. Buscando superar algumas
das dificuldades de estimação de métricas relacionadas ao processo de desenvolvimento, este
trabalho realiza, inicialmente, um estudo de ferramentas voltadas para tal objetivo e que estão
disponíveis no mercado. Em seguida, um conjunto de descritores do processo em questão e
também um conjunto de atributos básicos dos softwares será levantado. A partir de então, é
proposto um modelo que represente o processo de desenvolvimento de maneira simples e
eficiente. O modelo de processo do desenvolvimento na Engenharia de softwares relaciona as
características desse processo construtivo a classes de entidades desenvolvedoras, tal que se
possa estabelecer um comportamento homogêneo ao processo. Baseado nessa classificação,
são relacionados, de maneira direta, métricas (tempo e esforço) de desenvolvimento com os
atributos básicos dos softwares, definidos por Albrecht, visando a estimação de métricas. O
modelo de processo é baseado no mapa de Kohonen e o estimador de métricas será auxiliado
por redes neurais feed forward. Uma ferramenta de software (protótipo) é especificado em
Linguagem de modelamento unificada (UML). Esta ferramenta auxiliará a produção de
estimativas de tempo e de esforço de desenvolvimento de softwares. Comparações de
resultados obtidos serão realizadas com os disponibilizados na literatura consultada.
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