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Méthodologie d’aide à la décision pour l’élaboration et la sélection de la stratégie contractuelle des projets pétroliers complexes. / Decision aiding methodology for developing the Contractual Strategy of complex oil and gas development projectsMammeri, Massinissa 28 November 2017 (has links)
Un projet de développement d’une nouvelle installation pétrolière est lancé lorsque des études d’exploration et d’appréciation estiment que l’exploitation du gisement d’hydrocarbures découvert sera suffisamment rentable. La taille des projets rencontrés en industrie pétrolière impose de les découper en plusieurs périmètres. Chaque périmètre est attribué à un contracteur avec un type de contrat particulier, formant ainsi la stratégie contractuelle du projet. Durant le processus de sélection de la stratégie contractuelle, les entreprises pétrolières font face à trois difficultés récurrentes : 1) l’identification et la génération d’un nombre raisonnable et pertinent d’alternatives ; 2) l’évaluation des alternatives réalisables, qui dépendent de critères d’échelles et de natures différentes ; et enfin, 3) le besoin de justifier la solution proposée. La problématique de recherche est donc de concevoir une méthodologie d’aide à l’élaboration et la sélection de la stratégie contractuelle des projets de développement. Elle devra être la plus adaptée non seulement en termes de performances coûts, délais, mais devra également tenir compte des risques associés à ces performances. De plus, les interfaces entre contrats devront être considérées, car la performance collective de la stratégie peut être dégradée par rapport aux performances individuelles de chaque contrat. Ainsi, notre travail de recherche vise à mettre en place des solutions à la fois techniques et pratiques pour d'une part répondre à la question d'identification et de génération d'un ensemble pertinent d'alternatives de contrats et de stratégies contractuelles. D'autre part, construire et mettre en œuvre un système d’estimation et évaluation, permettant d’arriver à une proposition de stratégie contractuelle la plus performante pour le projet de développement. / A development project of a new oil and gas facility starts when the exploration and the appraisal studies estimate the exploitation of the hydrocarbon deposit is economically viable. The complexity and the size of the projects encountered in the industry impose to split them into several pieces, which represent the scope of future contracts. Each scope is then awarded to a contractor with a specific type of contract and selection mode, forming the contractual strategy to adopt in the project. During the contractual strategy selection process, oil companies encounters three recurring difficulties related to: 1) the identification of a reasonable and relevant set of alternatives; 2) the evaluation of potential alternatives, which depends on criteria from different scales and natures; and, 3) the need to substantiate the chosen contractual strategy solution. The research problem is to propose a decision aiding methodology for the development and selection of the most appropriate contractual strategy. It has to be the most performing in terms of cost and schedule, but should also consider the risks associated with these performances. In addition, the interfaces between the different contracts should also be considered, because the collective performance of the whole strategy may be degraded compared to the performance of each individual contract. Thereby, our work seeks to implement both technical and practical solutions to answer on the one hand the question of identification and generation of a relevant set of alternatives, at contracts and contractual strategy levels. On the other hand, to build and implement a system of estimation and evaluation of contractual strategies, allowing to come up with the most performing proposal to the upstream development project.
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Méthodes asynchrones de décomposition de domaine pour le calcul massivement parallèle / Asynchronous domain decomposition methods for massively parallel computingGbikpi benissan, Tete guillaume 18 December 2017 (has links)
Une large classe de méthodes numériques possède une propriété d’échelonnabilité connue comme étant la loi d’Amdahl. Elle constitue l’inconvénient majeur limitatif du calcul parallèle, en ce sens qu’elle établit une borne supérieure sur le nombre d’unités de traitement parallèles qui peuvent être utilisées pour accélérer un calcul. Des activités de recherche sont donc largement conduites à la fois sur les plans mathématiques et informatiques, pour repousser cette limite afin d’être en mesure de tirer le maximum des machines parallèles. Les méthodes de décomposition de domaine introduisent une approche naturelle et optimale pour résoudre de larges problèmes numériques de façon distribuée. Elles consistent en la division du domaine géométrique sur lequel une équation est définie, puis le traitement itératif de chaque sous-domaine, séparément, tout en assurant la continuité de la solution et de sa dérivée sur leur interface de jointure. Dans le présent travail, nous étudions la suppression de la limite d’accélération en appliquant des itérations asynchrones dans différents cadres de décomposition, à la fois de domaines spatiaux et temporels. Nous couvrons plusieurs aspects du développement d’algorithmes asynchrones, de l’analyse théorique de convergence à la mise en oeuvre effective. Nous aboutissons ainsi à des méthodes asynchrones efficaces pour la décomposition de domaine, ainsi qu’à une nouvelle bibliothèque de communication pour l’expérimentation asynchrone rapide d’applications scientifiques existantes. / An important class of numerical methods features a scalability property well known as the Amdahl’s law, which constitutes the main limiting drawback of parallel computing, as it establishes an upper bound on the number of parallel processing units that can be used to speed a computation up. Extensive research activities are therefore conducted on both mathematical and computer science aspects to increase this bound, in order to be able to squeeze the most out of parallel machines. Domain decomposition methods introduce a natural and optimal approach to solve large numerical problems in a distributed way. They consist in dividing the geometrical domain on which an equation is defined, then iteratively processing each sub-domain separately, while ensuring the continuity of the solution and of its derivative across the junction interface between them. In the present work, we investigate the removal of the scalability bound by the application of the asynchronous iterations theory in various decomposition frameworks, both for space and time domains. We cover various aspects of the development of asynchronous iterative algorithms, from theoretical convergence analysis to effective parallel implementation. Efficient asynchronous domain decomposition methods are thus successfully designed, as well as a new communication library for the quick asynchronous experimentation of existing scientific applications.
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Hierarchical carbon structures with vertically- aligned nanotube carpets for oil-water separation under different conditionsKiaei, Kimia 05 September 2019 (has links)
No description available.
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Hållbarhetsredovisning utifrån ett internt företagsperspektiv / Sustainability reporting from an internal company perspectiveEmilsson, Emma, Ljungkvist, Anna January 2023 (has links)
Bakgrund: Samhällets medvetenhet om klimathot har ökat det senaste decenniet, vilket medfört att fler företag både vill och måste redogöra för sitt ansvar, i och med nya lagkrav och direktiv om hållbarhetsrapporten. Hållbarhetsredovisningen kan ses som ett internt verktyg som hjälper företag att samla in, analysera och kommunicera hållbarhetsinformation. Tidigare forskning saknas om den komplexitet som kan uppstå inom organisationer vid upprättandet av hållbarhetsredovisningen, där strukturer och människor har en inverkan. Syfte och frågeställning: Uppsatsen syftar till att utforska och öka förståelsen för vilken betydelse strukturer och människor har för redovisningens kvalitet och omfattning. Studiens frågeställning är: Utifrån ett internt perspektiv, på vilket sätt har strukturer och människor en inverkan på hållbarhetsredovisningens innehåll? Metod: Studien utgår från en kvalitativ metod som inkluderar semistrukturerade intervjuer med sju personer från sju olika företag. Intervjuerna kompletteras med dokumentstudier genom att granska varje deltagande företags hållbarhetsredovisning. Resultat: Studiens resultat visar att regler har en inverkan på hållbarhetsredovisningen genom att de skapar struktur och tydliggör vad som måste rapporteras, hur informationen ska presenternas och vilka standarder som måste följas. Rutiner säkerställer att företag samlar in, bearbetar och rapporterar sitt hållbarhetsarbete på ett konsekvent och tillförlitligt sätt. Vidare spelar resurser en viktig roll eftersom företag måste ha tillgång till tillräckliga resurser både i form av tid, finansiella medel och personal för att kunna rapportera om sina hållbarhetsprestationer. I studien framkommer även att människor har en inverkan på hållbarhetsredovisningens innehåll genom sina handlingar, beteende och engagemang, likaså hjälper tidsaspekter företag att beskriva och mäta hur de har presterat över tid. Slutsats: Studien visar att tydliga regler, rutiner och tillräckliga resurser hjälper företag att upprätta en hållbarhetsredovisning av god kvalitet och omfattning. Människors handlingar, driv och tidsaspekter visar sig vara avgörande för hur hållbarhetsredovisningen utformas. / Background: Society's awareness of climate threats has increased in the last decade, which means that more companies both want and have to report on their responsibilities, partly due to new legal requirements and directives on the sustainability report. The sustainability report can be seen as an internal tool that helps companies collect, analyze and communicate sustainability information. Previous research is lacking on the complexity that can arise within organizations when preparing the sustainability report, where structures and people have an impact. Purpose and question: The purpose of this study is to explore and increase understanding of the importance of structures and people for the quality and extent of the accounting. The study's question is: From an internal perspective, in what way do structures and people have an impact on the content of the sustainability report? Method: The study is based on a qualitative method that includes semi-structured interviews with seven people from seven different companies. The interviews are supplemented with document studies by reviewing each participating company's sustainability report. Results: The study's results show that rules have an impact on sustainability reporting by creating structure and clarifying what must be reported, how the information must be presented and which standards must be followed. Routines ensure that companies collect, process and report their sustainability work in a consistent and reliable way. Furthermore, resources play an important role because companies must have access to sufficient resources both in the form of time, financial means and personnel to be able to report on their sustainability presentations. The study also shows that people have an impact on the content of the sustainability report, partly through their actions, behaviour and commitment, time aspects also help companies to describe and measure how they have performed over time. Conclusion: The study shows that clear rules, routines and sufficient resources help companies to create a sustainability report of good quality and extent. People's actions, commitment and time aspects prove to be decisive for how the sustainability report is designed.
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L’imaginaire constitutionnel en Afrique subsaharienneAzebové Tetang, Guy 12 1900 (has links)
Le principal dessein de cette recherche consiste à suggérer une nouvelle hypothèse pour rendre intelligible la fabrique des constitutions en Afrique et partant rouvrir l’instance pendante du « procès en mimétisme » dont elle a longtemps été l’objet.
Tout au long de leur histoire, les pays d’Afrique subsaharienne ont été imprégnés de représentations contradictoires du politique, justifiant ainsi le caractère ambivalent des structures politiques actuelles qui d’une certaine façon porte l’empreinte de ce processus de gestation troublée. Le processus de structuration politique de ces États amorcé depuis la période coloniale s’apparente à un « roman à la chaine » dont les chapitres n’ont pas cessé de se faire et de se défaire, à plusieurs « mains », locale et occidentale, à l’épreuve de cultures différentes. L’ordre constitutionnel qui en résulte renferme des références identitaires distinctes voire antinomiques, ayant une configuration protéiforme. Ce faisant, le constitutionnalisme des pays d’Afrique subsaharienne semble s’être installé dans l’hybride à la jonction des orientations inspirées par les États « du Nord » et réinterprétées par ceux qu’on dit « du Sud ». La circulation des modèles constitutionnels ou des « cultures constitutionnelles » en Afrique subsaharienne s’accompagne ainsi d’une réappropriation contextuelle.
Tout se passe alors comme si le constitutionnalisme de ces pays était pris dans un tourbillon tissé d’imaginaires imbriqués. Il en résulte une tension entre les « standards constitutionnels » occidentaux et « les localismes constitutionnels ». On est donc loin de l’espace de mimesis, ou de celui de « l’isomorphisme constitutionnel » suggéré par certains auteurs comme paradigme explicatif du constitutionnalisme en Afrique. Nous suggérons plutôt l’idée d’un « polymorphisme constitutionnel » qui résulte d’une ré-imagination constitutionnelle néanmoins inachevée. Cette étude en fera la démonstration. / The main purpose of this research is to suggest a new hypothesis to make intelligible the making of constitutions in Africa and thus reopen the pending instance of the "mimicry trial" of which it has long been the object.
Throughout their history, the countries of sub-Saharan Africa have been imbued with contradictory representations of politics, thus justifying the ambivalent nature of current political structures which in a way bears the indelible imprint of this process of troubled gestation. The process of political structuring of the States of sub-Saharan Africa initiated since the colonial period is similar to a "chain novel" whose chapters have not ceased to be made and undone, with several "hands", local and Western, to the test of distinct cultures. The resulting constitutional order contains distinct and even contradictory identity references, with a protean configuration. In doing so, the constitutionalism of the countries of sub-Saharan Africa seems to have settled in the hybrid at the junction of the orientations inspired by the States "of the North" and reinterpreted by those who are said to be "of the South". The circulation of constitutional models or “constitutional cultures” in sub-Saharan Africa is therefore accompanied by a contextual reappropriation.
Everything then happens as if the constitutionalism of African countries were caught in a whirlwind woven of intertwined imaginaries. The result is a tension between Western “constitutional standards” and “constitutional localisms”. We are far from the space of mimesis, or that of “constitutional isomorphism” suggested by certain authors as an explanatory paradigm of constitutionalism in Africa. Rather, we suggest the idea of a “constitutional polymorphism” that results from an unfinished constitutional re-imagining. This study will demonstrate this.
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En undersökning av digitala projektstyrningsverktyg : En fallstudie utförd på en kommunikationsbyrå i Visby / A survey of digital project management toolsAlho, Charlotta, Pettersson, Alice January 2023 (has links)
The study has been conducted on a communication agency called Outhousebyrån. The study examines the organization’s approach to project management and explores opportunities for enhancing efficiency. The study has also investigated how a new digital project management tool affects Outhousebyråns project management. Outhousebyrån faces difficulties structuring, planning and communicating during projects. The study has chosen to examine two digital project management tools, Trello and Monday. These have been tested on Outhousebyråns ongoing projects based on their needs and preferences. The purpose of the study is to present a digital project management tool to help Outhousebyrån structure and make their projects more effective. The study conducted is a qualitative case study where the data was collected using three methods, semi-structured interviews, observations, and sent-out questionnaires. The collected data has been analyzed based on theories that originates from Total Quality Management (TQM) and project management. Based on the analyzed result it was concluded that Outhousebyrån needed a digital project management tool, that would help them structure their projects. The study has compiled a list of the employees preferences regarding functions in a updated digital project management tool. The result showed that both tools fulfilled most of the expectations collected from the data. Since both tools could be implemented, the choice between the two was based on Mondays wider selection of functions and Outhousebyråns personal preferences. The result showed that Monday was more suitable for the organization. Finally, a proposal was presented on how Monday could be implemented for Outhousebyråns project management. / Studien har genomförts på en kommunikationsbyrå vid namn Outhousebyrån. Författarna undersöker hur organisationen arbetar med projektstyrning samt hur organisationen kan öka effektiviteten i sina projektarbeten. Författarna undersöker även hur digitala projektstyrningsverktyg påverkar organisationens projektarbeten. Värdorganisationen har i dagsläget svårigheter med strukturering, planering och kommunikation inom sina projekt. Därmed har författarna valt att studera två digitala projektstyrningsverktyg Trello och Monday för att underlätta organisationens projektarbete. Verktygen studeras genom att testa dem på organisationens pågående projekt utifrån deras behov och önskemål. Syftet med studien är att presentera ett digitalt projektstyrningsverktyg för Outhousebyrån för att effektivisera och strukturera organisationens dagliga projektarbete. Studien som utförts är en kvalitativ fallstudie där datainsamlingen gjordes med tre metoder. Semistrukturerade intervjuer, observationer och utskickade frågeställningar. Den insamlade datan har analyserats utifrån teorier som härstammar från offensiv kvalitetsutveckling och projektledning. Utifrån resultatet kan det konstateras att Outhousebyrån har ett behov av ett mer strukturerat digitalt projektstyrningsverktyg. Det har sammanställts en lista på organisationens önskemål kring funktioner i ett nytt verktyg, där det kan konstateras att samtliga medarbetare hade gemensamma behov. Utifrån behoven från Outhousebyrån har de två projektstyrningsverktygen Trello och Monday testats där det visade sig att Monday var lämpligast för värdorganisationens önskemål och behov. Valet gjordes utifrån att Monday har bredare utbud av funktioner samt på grund av projektledarens personliga preferenser. Slutligen presenteras ett förslag på hur en implementering kan genomföras i värdorganisationen.
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Adapting a data-driven battery ageing model to make remaining-useful-life estimations using dynamic vehicle data / Anpassning av datadriven batteriåldringsmodell för uppskattningar av återstående livslängd från dynamiska fordonsdataPhatarphod, Viraj January 2021 (has links)
Transportsektorn är en av världens största producenter av växthusgas därav är dess avkarbonisering essentiell för att uppnå Parisavtalets mål för CO2-emissioner. Ett viktigt steg för att uppnå dessa mål utförs genom elektrifiering. Litium-jon-batterier (eng. litium-ion batteries, ’LIB’) har blivit väldigt populära energilagringssystem för batteridrivna elektriska fordon (eng. battery electric vehicles, ’BEV’) men tenderar att åldras, precis som alla andra batterier. Därav krävs forskning kring batteriföråldring på grund av nedbrytningsprocessernas inverkan på prissättningen, prestationerna och miljöpåverkan av BEV. Olika modeller används för att beskriva batteriernas åldrande. Datadrivna modeller som förutspår batteriers livstid ökar i popularitet vars noggrannhet och prestationer till stor del beror på indatats kvalitet. Formatet för tidsinhämtade data kräver enorma mängder lagringsutrymme, hög processkapacitet och längre processer; något ’reducerad’ eller ’aggregerad’ data delvis åtgärdar. Denna avhandling fokuserar på att utveckla en metodik för användning av dynamiska fordonsdata i ’aggregerad’ form. Tidsloggade data inhämtade från kallklimatstesting av Scanias BEV-prototyp användes varav interaktionseffekterna mellan diverse fordonsparametrar samt deras effekt på batteriåldring utifrån en batteriåldringsmodell analyserades. Olika tillvägagångssätt för strukturering av dynamiska fordonsdata i modellen undersöktes också. Tolv aggregeringsscenarion designades och testades. Dessutom valdes tre scenarion för uppskattningar och jämförelser av återstående användbar livslängd (eng. remaining-useful-life, ’RUL’) tillsammans med resultat från tidsinhämtade data. Slutligen drogs slutsatser om: parameterinteraktioner, struktur av dynamiska fordonsdata och RUL. Flera framtida utvecklingsområden har också föreslagits bland annat: tester av andra aggregeringstekniker, utöka modellen till tjänstefordon samt kategorisera användningsbeteenden av fordon för att förbättra RUL-uppskattningar. / The transport sector is one of the world’s largest greenhouse gas producing sector and it’s decarbonisation is imperative to achieve the CO2 emission targets set by the Paris Agreement. One important step towards achieving these targets is through electrification of the sector. Lithium-ion batteries (LIBs) have become very popular energy storage systems for battery electric vehicles (BEVs). However, LIBs like all other batteries, tend to age. Hence, the study of the battery ageing phenomena is very essential since the degradation in battery characteristics hugely determines the cost, performance and the environmental impact of BEVs. Different modelling approaches are used to represent battery ageing behaviour. Data-driven models for predicting the lifetime of batteries are becoming popular. However, the accuracy and performance of data-driven models largely depends upon the quality of data being used as the input. Time-sampled format of logging data results in huge data files requiring enormous amounts of storage space, high processing power requirements and longer processing times. Instead, using data in a ’reduced’ or ‘aggregated’ form can help in addressing these issues. This thesis work focuses on developing a methodology for using dynamic vehicle data in an ‘aggregated’ form. Time-sampled data from a Scania prototype BEV truck, recorded during cold climate test, was used. The interaction effects between various vehicle parameters and their effect on battery ageing in a battery ageing model were analyzed. Different approaches to structuring dynamic vehicle data for use in the model were also studied. Twelve aggregation scenarios were designed and tested. Furthermore, three scenarios were selected for making remaining-useful-life (RUL) estimations and compared alongside time-sampled data results. Finally, conclusions about parameter interactions, structuring of dynamic vehicle data and RUL estimations were drawn. Several next steps for future work have also been suggested such as testing other aggregation techniques, extending the model to vehicle fleets and categorizing vehicle usage behaviours to make better RUL estimations.
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Black/white joint small business ventures in South AfricaMiller, Patricia Kathryn 06 1900 (has links)
The political history of South Africa, especially that of the apartheid years, has affected
the structuring and functioning of business in the country profoundly. In general, White
business is highly developed and formal, with access to financial and infrastructural
support. Black business is often subsistence-based, informal and struggles for access to
support mechanisms.
These structural inequities have had a depressing impact on the economy that will
continue if they are not resolved. Following the 1994 elections, policies and legislation
have been introduced aimed at redressing structural imbalances. There is thus both a
political and an economic imperative to bridge the gaps that have arisen between Black and
White business.
The study proposes Black/White joint ventures as a mechanism to this end.
The history of Black/White relationships means that these enterprises are likely to face
many problems. A model has been developed through the study for the formulation,
structuring and operation of Black/White joint ventures that takes into account the factors
that are likely to impact on these ventures and affect their success potential. The process
of applying the model in practice is directed towards results that are not prejudiced by the
background of the parties to the venture.
The study expands the concept of joint ventures within the South African context to
incorporate initiatives along a continuum ranging from extensions to employment to full
joint ventures. Depending on its nature and objectives, a venture may be placed and
remain at any stage along the continuum, or may progress along it.
Case studies of Black/White joint ventures were investigated in depth and analysed in
terms of the application of the model, in order to determine the relevance of the model.
In all cases, the success or failure of the venture under scrutiny could be ascribed to the
way in which the presence of various elements identified as being components of the
model had been accommodated in practice within the venture.
The use of the model when applied to formulating, structuring and operating a Black/White
joint venture can contribute to its success potential. / Business Management / DBL
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Les éléments entourant le passage à l'acte sous forme de co-délinquance au QuébecGagné-Tardif, Xanthia 04 1900 (has links)
Les premières études recensées ayant traité de la co-délinquance ont plus de cent ans. Comme il s’agit d’un sujet qui a de l’histoire, il y a eu une grande évolution dans la façon d’aborder la question et dans les méthodologies employées. Mais, ce n’est que depuis quelques années que la co-délinquance est étudiée par l’entremise de données d’arrestations policières et c’est ce type de données qui sera utilisé pour répondre à l’objectif principal, celui-ci étant la détermination des conditions expliquant le recours ou non à la co-délinquance pour commettre une infraction criminelle. De plus, pour répondre à notre objectif de recherche, nous avons opté pour une théorie structurante du crime, approche qui n’avait jamais été utilisé auparavant dans les études sur la co-délinquance.
Comme méthodologie, nous avons utilisé un échantillon composé de 9 103 participations criminelles, de 8 243 événements distincts et de 3 356 individus et plusieurs prédicteurs ont été analysés afin de déterminer lesquels expliquent le mieux la co-délinquance. L’âge, le genre, les antécédents criminels, l’urbanité et le type de crimes sont toutes des variables qui ont été considérées. L’urbanité représente une nouveauté dans ce type de recherche, puisque nous avons recensé que très peu d’études ayant abordées la question. Alors, que pour le type de crime, nous l’avons détaillé, comme aucune étude sur la co-délinquance ne l’a fait auparavant (23 catégories d’infractions). Ce détail nous permet donc de bien cibler l’impact de chaque délit sur le recours à la co-délinquance.
Le résultat émergeant des analyses de régression logistique est que le recours à la co-délinquance s’explique principalement par le type de crime commis, certains actes criminels sont plus propices à la co-délinquance que d’autres. Nous constatons également que les autres variables analysées ont très peu ou pas d’impact sur le recours à la co-délinquance, que ce soit l’âge, le genre, les antécédents criminels ou même l’urbanité. / First studies related to co-offending are more than a century old. Since this subject has greatly evolved during this time, the approach and the methodology used have been developed to follow the subject’s progression. But it is only in recent years that co-offending is studied through police arrest data and it is this type of data that will be used to meet the main objective which aims to be to determine conditions explaining the use or not to co-delinquency for committing a criminal offense. In addition, to meet our research objective, we opted for structuring a theory of the crime, an approach that had never been used before in studies of co-offending.
As a methodology, we used a sample of 9 103 criminal participations, 8 243 separate events and 3 356 individuals and several predictors were analyzed to determine which best explain the co-offending. Age, gender, criminal history, urbanity and type of crimes are all variables that were considered. Urbanity is a novelty in this research, since we identified very few studies have addressed the issue. For the type of crime, we have detailed this variable as no studies on co-offending have done previously (23 categories of offenses). This detail allows us to identify the impact of each offense on the use of co-offending.
The results obtained from the logistic regression analyze show that the use of co-offending is mainly due to the crime’s type; some crimes are more propitious to co-offending than others. We also find that other variables analyzed (age, gender, criminal history and urbanity) have little or no impact on the use of co-offending.
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Biologie de la conservation de la gorgone rouge de Méditerranée, Paramuricea clavata, dans le contexte actuel du changement climatiqueMokhtar-Jamai, Kenza 23 September 2011 (has links)
La gorgone rouge, Paramuricea clavata (Cnidaire, Octocoralliaire), est une espèce sessile, longévive à faible croissance dont les populations présentent une lente dynamique. Cette espèce est caractérisée par une phase larvaire pélagique qui représente l’unique phase de dispersion potentielle au cours du cycle de vie de cette espèce. P. clavata est une espèce clé des assemblages à coralligène de Méditerranée, qui subit les effets combinés des activités de plongée sous-marine et du changement climatique. Dans ce contexte, il était donc fondamental d’approfondir les connaissances sur les traits d’histoire de vie, la biologie et l’écologie de cette espèce. L’objectif de ce travail était d’étudier, à l’aide d’une approche génétique, les facteurs biologiques et écologiques clés qui devraient être importants pour la réponse de l’espèce aux changements environnementaux. Parmi ces facteurs, la dispersion larvaire joue un rôle fondamental dans la dynamique et la connectivité des populations marines. Dans le contexte actuel des fortes pressions anthropiques, la compréhension des degrés de connectivité entre les populations est primordiale pour évaluer le devenir des populations, face au changement climatique, et pour mettre en place des plans de conservation et des réseaux d’aires marines protégées. / The red gorgonian, Paramuricea clavata (Cnidaria, Octocorallia), is a sessile, long-lived and slow growing species which displays slow population dynamics. This species is characterized by a pelagic larval phase that represents the sole potential phase of dispersal during the life cycle of this species. P. clavata is a key species of coralligenous assemblages of the Mediterranean Sea which undergoes the combined effects of diving activities and climate change. In this context, extending the knowledge about life history traits, biology and ecology of the red gorgonian was of fundamental importance. Using a genetic approach, the goal of this work was to study some key biological and ecological factors which should be important for the response of this species to environmental changes. Among these factors, larval dispersal plays a major role in driving marine population dynamics and connectivity. In the current context of strong anthropic pressures, understanding the level of population connectivity is primordial to evaluate population outcome, facing climate change, and to develop conservation plans as well as to design marine reservenetworks.
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