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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Effekten av olika logistiklösningar : En studie kring fördelar och nackdelar med tredjepartslogistik och inbärning till ett projekt i Dalarna

Andersson, Julia, Liedström, Matilda January 2021 (has links)
Inom byggbranschen har man börjat sett fördelar med att titta mer på logistiken iolika byggprojekt. Många olika studier har utförts kring vilka lösningar som finnsoch hur man kan använda dem.Denna studie utförs i samarbete med Skanska Sverige AB. Studien syftar till att påolika sätt undersöka vilka fördelar och nackdelar man kan se med att använda sigav logistiktjänsterna terminalisering och inbärning till ett byggprojekt i Dalarna.Byggprojektet som utgör det specifika fallet i studien är ett ombyggnadsprojekt aven grundskola. Elever vistas i detta skolområde samtidigt som ombyggnationenutförs etappvis inom det stängda arbetsområdet. Studien innefattar även tredje mandär trygghetsupplevelse kring arbetsplatsen undersöks. Inbärningens användbarhetdiskuteras därefter utifrån trygghetsupplevelsen kring och inom arbetsplatsen samtutifrån ekonomiskt och ekologiskt perspektiv.Metoder som används i studien är intervjuer med somliga från projektets ledning,en logistiker på Skanska, rektor för årskurs F-6, yrkesarbetare samt tredje man.Utöver dessa intervjuer utförs även en fältstudie som involverar observationer ochmätningar. Som avslut utförs överslagsberäkningar för att se om användning av ettexternt företag kan leda till ekonomisk lönsamhet.Studiens resultat visar hur man inom företaget ser på logistiklösningarnaterminalisering och inbärning idag. Här visas även vilka fördelar och nackdelarolika parter ser med tjänsterna. Fältstudiens mätningar visar hur många av tredjeman som rör sig kring arbetsområdet i anslutning till att skoldagen börjar.Överslagsberäkningar visar på att man kan se en besparing ifall man använder sigav ett inbärningsföretag som arbetar under kvällstid och detta sker i samband medatt man använder sig av terminalisering.Studiens slutsatser är att det inte finns en allmän lösning till hur logistikfrågan skalösas på olika projekt. Om det finns möjlighet för terminalisering i området ärdetta samt inbärning ett alternativ för projektet. / Within the construction industry the advantages of looking at the logistics todifferent projects has been acknowledged during the past couple of years.This study has been written in collaboration with Skanska Sverige AB. Thepurpose of the study is to, in different ways, examine what advantages anddisadvantages there are in using the logistics solutions terminalization (also knownto be a part of Third Party Logistics) and inside delivery to a specific project inDalarna, Sweden. This project is a remodeling project of a school with studentsfrom six to sixteen years old. Within the school area new parts of the school isbuilt while students are located in the yet existent buildings. This infer thatstudents move around the construction sites daily. The study also involves thirdparty people and how these people feel about the large transports connected to theproject. The inside delivery utility is then discussed based on the securityexperience within and around the construction site along with the economic andecological perspective of the service.The methods used in this study are interviews with three people of the projectmanagement, one person that works with logistics at the company, the headmasterof the younger students, skilled workers and third party people. Furthermore afield study is done that includes measurements and observations. As a close,calculations are done to determine if a economical profitability could be possibleby using inside delivery.Results from the study show how the logistics solutions terminalization and insidedelivery is looked at within Skanska today. Here, the advantages anddisadvantages with the different services are displayed from the perspectives of thepeople who were interviewed. The results from the measurements from the fieldstudy presents how many third party people that move adjacent to the two activeconstruction sites when the school day begins. The calculations show that it iseconomically beneficial to use inside delivery after the end of the workday whileused with terminalization.Conclusions of the study indicate that there are no overall solutions regarding howthe logistics must be used in different projects. If there is a possibility to use terminalization in the area where the project is situated, this, along with insidedelivery, is a good alternative for the project.
32

Cox模式有時間相依共變數下預測問題之研究

陳志豪, Chen,Chih-Hao Unknown Date (has links)
共變數的值會隨著時間而改變時,我們稱之為時間相依之共變數。時間相依之共變數往往具有重複測量的特性,也是長期資料裡最常見到的一種共變數形態;在對時間相依之共變數進行重複測量時,可以考慮每次測量的間隔時間相同或是間隔時間不同兩種情形。在間隔時間相同的情形下,我們可以忽略間隔時間所產生的效應,利用分組的Cox模式或是合併的羅吉斯迴歸模式來分析,而合併的羅吉斯迴歸是一種把資料視為“對象 時間單位”形態的分析方法;此外,分組的Cox模式和合併的羅吉斯迴歸模式也都可以用來預測存活機率。在某些條件滿足下,D’Agostino等六人在1990年已經證明出這兩個模式所得到的結果會很接近。 當間隔時間為不同時,我們可以用計數過程下的Cox模式來分析,在計數過程下的Cox模式中,資料是以“對象 區間”的形態來分析。2001年Bruijne等人則是建議把間隔時間也視為一個時間相依之共變數,並將其以B-spline函數加至模式中分析;在我們論文的實證分析裡也顯示間隔時間在延伸的Cox模式中的確是個很顯著的時間相依之共變數。延伸的Cox模式為間隔時間不同下的時間相依之共變數提供了另一個分析方法。至於在時間相依之共變數的預測方面,我們是以指數趨勢平滑法來預測其未來時間點的數值;利用預測出來的時間相依之共變數值再搭配延伸的Cox模式即可預測未來的存活機率。 / It is so called “time-dependent covariates” that the values of covariates change over time. Time-dependent covariates are measured repeatedly and often appear in the longitudinal data. Time-dependent covariates can be regularly or irregularly measured. In the regular case, we can ignore the TEL(time elapsed since last observation) effect and the grouped Cox model or the pooled logistic regression model is employed to anlalyze. The pooled logistic regression is an analytic method using the“person-period”approach. The grouped Cox model and the pooled logistic regression model also can be used to predict survival probablity. D’Agostino et al. (1990) had proved that pooled logistic regression model is asymptotically equivalent to the grouped Cox model. If time-dependent covariates are observed irregularly, Cox model under counting process may be taken into account. Before making the prediction we must turn the original data into“person-interval”form, and this data form is also suitable for the prediction of grouped Cox model in regular measurements. de Bruijne et al.(2001) first considered TEL as a time-dependent covariate and used B-spline function to model it in their proposed extended Cox model. We also show that TEL is a very significant time-dependent covariate in our paper. The extended Cox model provided an alternative for the irregularly measured time-dependent covariates. On the other hand, we use exponential smoothing with trend to predict the future value of time-dependent covariates. Using the predicted values with the extended Cox model then we can predict survival probablity.
33

Sequential probability ratio tests based on grouped observations

Eger, Karl-Heinz, Tsoy, Evgeni Borisovich 26 June 2010 (has links)
This paper deals with sequential likelihood ratio tests based on grouped observations. It is demonstrated that the method of conjugated parameter pairs known from the non-grouped case can be extended to the grouped case obtaining Waldlike approximations for the OC- and ASN- function. For near hypotheses so-called F-optimal groupings are recommended. As example an SPRT based on grouped observations for the parameter of an exponentially distributed random variable is considered.
34

Les agglomérations "secondaires" gallo-romaines dans le Massif Central : (cités des arvernes, vellaves, gabales, rutenes, cadurques et lémovices), 1er siècle avant J.-C. - Ve siècle après J.-C. / Gallo-Roman "secondary" agglomerations in the Massif Central

Baret, Florian 08 June 2015 (has links)
Parmi les formes d’organisation de l’habitat antique, il en est une qui est longtemps restée en retrait dans la recherche archéologique française. Les agglomérations antiques, qui correspondent à des formes très variées d’habitat groupé, suscitent un intérêt majeur depuis une vingtaine d’années.L’étude historiographique, à l’échelle de la Gaule, fait ressortir un espace en marge des recherches, celui des cités du Massif central. Cette thèse propose donc d’étudier les agglomérations antiques des cités arverne, vellave, gabale, rutène, cadurque et lémovice entre le Ier s. av. J.-C. et le Ve s. ap. J.-C. Les objectifs sont multiples. Il a été nécessaire dans un premier temps d’établir un corpus de sites à partir de la bibliographie régionale. Celui-ci est composé de notices normalisées au sein desquelles l’ensemble des données actuellement disponibles a été présenté. Pour répondre aux questions d’organisation spatiale et de classification, les données bibliographiques recueillies, complétées par des opérations de terrain (prospections terrestres, aériennes, géophysiques, relevés topographiques), ont été synthétisées à partir d’une série de descripteurs archéologiques développés sur le modèle d’Archaeomedes. L’emploi de ces descripteurs a permis la mise en œuvre d’analyses statistiques multivariées afin de dépasser le simple classement par niveaux de fiabilité (sites rejetés, agglomérations hypothétiques, agglomérations avérées). C’est sur la base de la classification retenue après différents tests et sur la hiérarchie urbaine proposée que les analyses spatiales et morphologiques permettent de brosser un tableau complet de l’armature urbaine des cités antiques du Massif central.Les résultats obtenus ont permis d’exposer et de comprendre à la fois les relations entre les agglomérations et le milieu naturel mais aussi avec leur environnement archéologique par l’étude de leurs relations avec l’habitat rural, les chefs-lieux, les limites des cités, leur territoire théorique, les axes de communications terrestres et fluviaux. En changeant d’échelle, l’analyse interne des agglomérations permet d’appréhender à la fois leur morphologie générale mais aussi la place des édifices monumentaux au sein des agglomérations et au sein des cités, le rôle de l’artisanat, les aménagements hydrauliques, … Pour l’analyse de l’armature urbaine, la thèse prend nécessairement en compte l’évolution chronologique des agglomérations à travers leur origine protohistorique, leur évolution durant l’Antiquité et leur devenir au début du Moyen Âge.Pour mener à bien ce travail, il a été nécessaire de croiser les approches documentaires (bibliographie, opérations de terrains), de croiser les échelles d’analyse (du site au Massif central) et de comparer les résultats à ceux des régions voisines. Passées, les analyses statistiques, c’est à partir d’un SIG et d’une base de données que l’ensemble des synthèses a pu être mené.Cette thèse constitue la première synthèse sur les agglomérations antiques des cités du Massif central. Les résultats mettent en avant l’importance des agglomérations dans le système de peuplement et des armatures urbaines variables entre les cités mais qui semblent structurées en partie par le relief et les axes de communications. Les fonctions présentes au sein des agglomérations, si elles sont variées et récurrentes, montrent des spécificités entre les cités mais aussi une hétérogénéité au sein de chacune d’elles. Enfin, l’analyse chronologique montre une réduction du nombre des agglomérations à partir du IIIe siècle mais pas leur disparition. De même, de nouvelles formes d’habitats groupés apparaissent à partir du IVe siècle attestant non pas une crise mais une évolution dans l’organisation urbaine des cités pour répondre à de nouveaux besoins. / Among the forms of organization one can observe in the ancient habitat, there is one particular structure that has been slightly ignored by French archeologists: the lesser urbanized settlements. However, in the last twenty years, small towns have attracted renewed interest.A historiographical study of the Gaul territory highlighted a less studied group of population: the ancient peoples of the Massif Central. In this thesis we intend to have a closer look at such populations as the Arvernes, the Vellaves, the Gabales, the Rutenes, the Cadurques, and the Lemovices from 1st century B.C. - 5th century A.D. We first established a corpus of sites starting with the study of the regional bibliography, which enabled us to create records for each area. We completed this first approach with several field operations such as ground, aerial, geophysical and topographical surveys. All those data were synthesized in a series of archaeological descriptors developed using the Archaeomedes model.The use of such descriptors enabled us to develop some statistical analyses and go beyond the simple reliability factor (which allows the distinction between rejected sites, hypothetical and true urbanized clusters). On the basis of our tested and proven classification, keeping in mind the suggested urban hierarchy and with the help of our spatial and morphological analyses, we were able to obtain a more complete picture of the urban framework of the ancient cities of the Massif Central.The data collected allowed us to better apprehend and understand the relation between such urban clusters and their natural environment, but also to place them in an archaeological context by studying the links between rural housing, the ancient administrative structure (chef-lieu), the city and territory limits, and the major communication routes (land and water). Through a multi-scale study of those population clusters, we were able to determine their general structure, to look at the role of local crafts and trade but also the place of major buildings, and waterworks. We took specific care to the chronological evolution in thosesmall towns by looking at them from their protohistoric beginnings through Antiquity and until early medieval times.While we cross-referenced all the different sources (bibliography and field surveys) and the analysis scales within the Massif Central, we also did a cross-comparison with other neighboring areas in order to validate such work. Besides the statistical data, we used the Geographic Information System and our database to reach our conclusions.This thesis aims at uncovering the reality of those ancient population clusters present in the Massif Central. Our results showed clearly the importance of those in the settlement system, their different forms structured according to the local geography and major trade routes. The functions/positions available in small towns were varied and recurrent but also corresponded to specific trades within each structure while remaining homogeneous.Through our chronological analysis we were able to point out a significant reduction in their numbers starting in the third century, though not their disappearing. In the 4th century new types of population clusters appeared, not as a response to an acute crisis, but more as a result of an evolution called on by new needs.

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