Indiana University-Purdue University Indianapolis (IUPUI) / Protein malfunction can cause human diseases, which makes the protein a target in the process of drug discovery. In-depth knowledge of how protein functions can widely contribute to the understanding of the mechanism of these diseases. Protein functions are determined by protein structures and their dynamic properties. Protein dynamics refers to the constant physical movement of atoms in a protein, which may result in the transition between different conformational states of the protein. These conformational transitions are critically important for the proteins to function. Understanding protein dynamics can help to understand and interfere with the conformational states and transitions, and thus with the function of the protein. If we can understand the mechanism of conformational transition of protein, we can design molecules to regulate this process and regulate the protein functions for new drug discovery. Protein Dynamics can be simulated by Molecular Dynamics (MD) Simulations. The MD simulation data generated are spatial-temporal and therefore very high dimensional. To analyze the data, distinguishing various atomic interactions within a protein by interpreting their 3D coordinate values plays a significant role. Since the data is humongous, the essential step is to find ways to interpret the data by generating more efficient algorithms to reduce the dimensionality and developing user-friendly visualization tools to find patterns and trends, which are not usually attainable by traditional methods of data process. The typical allosteric long-range nature of the interactions that lead to large conformational transition, pin-pointing the underlying forces and pathways responsible for the global conformational transition at atomic level is very challenging. To address the problems, Various analytical techniques are performed on the simulation data to better understand the mechanism of protein dynamics at atomic level by developing a new program called Probing Long-distance interactions by Tapping into Paired-Distances (PLITIP), which contains a set of new tools based on analysis of paired distances to remove the interference of the translation and rotation of the protein itself and therefore can capture the absolute changes within the protein. Firstly, we developed a tool called Decomposition of Paired Distances (DPD). This tool generates a distance matrix of all paired residues from our simulation data. This paired distance matrix therefore is not subjected to the interference of the translation or rotation of the protein and can capture the absolute changes within the protein. This matrix is then decomposed by DPD using Principal Component Analysis (PCA) to reduce dimensionality and to capture the largest structural variation. To showcase how DPD works, two protein systems, HIV-1 protease and 14-3-3 σ, that both have tremendous structural changes and conformational transitions as displayed by their MD simulation trajectories. The largest structural variation and conformational transition were captured by the first principal component in both cases. In addition, structural clustering and ranking of representative frames by their PC1 values revealed the long-distance nature of the conformational transition and locked the key candidate regions that might be responsible for the large conformational transitions. Secondly, to facilitate further analysis of identification of the long-distance path, a tool called Pearson Coefficient Spiral (PCP) that generates and visualizes Pearson Coefficient to measure the linear correlation between any two sets of residue pairs is developed. PCP allows users to fix one residue pair and examine the correlation of its change with other residue pairs. Thirdly, a set of visualization tools that generate paired atomic distances for the shortlisted candidate residue and captured significant interactions among them were developed. The first tool is the Residue Interaction Network Graph for Paired Atomic Distances (NG-PAD), which not only generates paired atomic distances for the shortlisted candidate residues, but also display significant interactions by a Network Graph for convenient visualization. Second, the Chord Diagram for Interaction Mapping (CD-IP) was developed to map the interactions to protein secondary structural elements and to further narrow down important interactions. Third, a Distance Plotting for Direct Comparison (DP-DC), which plots any two paired distances at user’s choice, either at residue or atomic level, to facilitate identification of similar or opposite pattern change of distances along the simulation time. All the above tools of PLITIP enabled us to identify critical residues contributing to the large conformational transitions in both HIV-1 protease and 14-3-3σ proteins. Beside the above major project, a side project of developing tools to study protein pseudo-symmetry is also reported. It has been proposed that symmetry provides protein stability, opportunities for allosteric regulation, and even functionality. This tool helps us to answer the questions of why there is a deviation from perfect symmetry in protein and how to quantify it.

Summaries in English and Afrikaans / Daar is gepoog om 'n omvattende, algemeen geldige maatstaf te vind waarmee enige opvoeding vir outentisiteit geevalueer kan word. Die moontlikheid dat die "essensiestruktuur van behoorlike volwassenewees en van opvoedingsdoel" (ES) hieraan voldoen, is ondersoek. Die genoemde essensiestruktuur (ES) is in 'n modeldiagram CESM) saamgevat. Dit bevat die volgende essensies: 'religiositeit', die 'etiese', 'affektiwiteit', 'liggaamlikheid'. 'nasionaliteit' (insluitende 'kulturaliteit'. 'historisiteit' en die 'politiese'), die 'estetiese'. 'individualiteit'. 'sosialiteit'. die 'ekonomiese'. 'vryheid'. 'gesag'. 'taal' en 'redelikheid'. asook die sewe normbeelde wat 'n substruktuur van die 'etiese' is. 'Religiositeit' is hierargies die mees belangrikste essensie. gevolg deur die 'etiese'. Aldie ander essensies verkeer op 'n derde niveau van belangrikheid. Om outentiek te wees behoort 'n opvoedingseksemplaar aan boge noemde hierargie te voldoen. Elk van die genoemde essensies is verduidelik, asook hulle samehangende verbandhoudendheid binne die ESM. Die harmonie binne hierdie gestruktureerdheid is van deurslaggewende belang vir die begryping van outentisiteit by opvoeding. 'n Evalueringsmetode. bekend as ''essensiestruktuur-analise" (ES-analise). is uit bogenoemde deur die navorser ontwikkel. 'n Uiteensetting van mikro-. meso- en makro ES-analise is oak verstrek. Beskrywings van eksemplare van opvoeding en van aanverwante opvoedingsaangeleenthede word in die lig van die ESM geanaliseer. Hoe meer 'n opvoedingseksemplaar ooreenstem met die ESM hoe nader beweeg dit aan outentisiteit. en omgekeerd. Ter illustrasie van die toepassingsmoontlikhede van ES-analise is die mensbeskouing van C.K. Oberholzer. die kindbeskouing van J.C. Coetzee. die Christelike lewensopvatting, die wereldbeskouing van Albert Schweitzer en die opvoedingsleer van die Klassisisme aan ES-analises onderwerp. Die Christelike lewensopvatting kon as outentiek geevalueer word, terwyl die mensbeskouing van Oberholzer. die kindbeskouing van Coetzee en die wereld beskouing van Schweitzer naby aan outentisiteit beweeg. Die opvoedingsleer van die Klassisisme vertoon heelparty essensie-diskrepansies. Die hipotese, dat ES-analise 'n betroubare evalueringsmaatstaf vir outentieke opvoeding kan wees, is bevestig. Derhalwe kon die aanwending vanESanalise oar 'n wye spektrum aanbeveel word. byvoorbeeld by histories opvoedkundige eksemplare, godsdienslere. skoolstelsels en meegaande kurrikula en by die ontwikkeling van opvoedingsprogramme. Die huidige opvoeding en kon temporere leefwyse kan in die toekoms verbeter word indien ES-analise daadwerklik toegepas sou word. / An effort was made to find a universally valid criterion to evaluate any education for authenticity. The "essence-structure of proper adulthood and of education-aim" (ES) was investigated in this regard. This essence-structure (ES) was condensed in a model diagram (ESM). It includes the fo 11 owing essences: · re 1 i gi ousness · , the · ethi ca 1 ' , · affec tiveness'. 'bodiliness'. 'nationality' ('culturality'. 'historicity' and the 'political'), the 'aesthetical'. 'individuality', 'sociality·. the 'economical'. 'freedom·. 'authority'. 'language' and 'rationality'. as well as the seven norm images - a substructure of the 'ethical'. Hierarchically 'religiousness· is the most important essence. followed by the 'ethical·. All other essences exist on a third 1 eve 1 of importance. To qualify as authentic an exemplar of education ought to comply with the above-mentioned hierarchy. Each of the essences and their interrelatedness within the ESM were discussed. The harmonious co-existence within this structuredness is of paramount importance in understanding educational authenticity. Emanating from the above-mentioned an evaluation method. known as "essence structure-analysis" (ES analysis). was developed. Micro. meso and macro-ESanalysis were also explained. Descriptions of exemplars of education and of educationally related matters are analysed using the ESM as the criterion. The more an exemplar corresponds with the ESM. the more it re sembles authenticity, and vice versa. To demonstrate the application potential of ES analysis C.K. Oberholzer's view of man. J.C. Coetzee's view on childhood. the Christian life-view. Albert Schweitzer's world-view and the educational doctrine of the Classicism were subjected toES analyses. The Christian life-view could be evaluated as authentic. while Oberholzer's view of man. Coetzee's view on childhood and Schweitzer's world-view are resembling authenticity closely. The educational doctrine of the Classicism revealed several essence discre pancies. (viii) The hypothesis. that ES analysis can be a reliable evaluation criterion for authentic education. was confirmed. It could thus be recommended that ESanalysis be implemented over a broad spectrum. for example when studying historico-educational exemplars. doctrines of religion. school systems and curricula and assisting in developing educational programs. The contemporary education and way of life can be ameliorated in the future if ES analysis is applied actively. / Educational Studies / D.Ed. (Philosophy of Education)

Seit den 90er Jahren ist die Wettbewerbsstruktur im europäischen Eisenbahngüterverkehr starken Veränderungen unterworfen. Die Auflösung staatlicher Monopole sowie die Öffnung nationaler Märkte implizieren einen intensivierten Wettbewerb, bieten jedoch gleichzeitig die Möglichkeit, sich über neuartige Formen der Allianzbildung Wettbewerbsvorteile zu sichern bzw. Eintrittschancen in neue Transportmärkte zu nutzen. Die Einführung wettbewerblicher Marktstrukturen im Eisenbahngüterverkehr betrifft einerseits die Schaffung gleicher Wettbewerbsvoraussetzungen im Verhältnis der Verkehrsträger untereinander (intermodal). Weiterhin steht die Einführung von Wettbewerb zwischen Eisenbahnverkehrsunternehmen im Vordergrund (intramodal). Die vorliegende Arbeit betrachtet Allianzmöglichkeiten entlang beider Dimensionen: im Mittelpunkt stehen Partnerschaften zwischen Eisenbahnverkehrsunternehmen und/oder intermodalen Partnern, die grundsätzlich auf die Gestaltung des intramodalen Wettbewerbs ausgerichtet sind. Aufgrund des Einbezugs intermodaler Partner, der vor dem Hintergrund integrierter Logistikketten immer bedeutsamer wird, gelangt die Perspektive der Beeinflussung des Wettbewerbs der Verkehrsträger untereinander mittels Allianzen ebenfalls in das Blickfeld der Untersuchung. Übergeordnetes Ziel der Arbeit stellt die Analyse des Allianzphänomens und die Systematisierung spezifischer Allianzmodelle im europäischen Eisenbahngüterverkehr vor dem Hintergrund der sich fortlaufend verändernden Marktstruktur und fortgesetzten Deregulierung dieser Branche dar. Das Hauptinteresse gilt der Allianzrelevanz in dieser Branche im allgemeinen und der Verdeutlichung branchenstrukturprägender Allianzmuster im besonderen. Betriebswirtschaftlicher Forschung in diesem Branchenumfeld soll damit ein stärkeres Gewicht beigemessen werden.

Summaries in English and Afrikaans / Daar is gepoog om 'n omvattende, algemeen geldige maatstaf te vind waarmee enige opvoeding vir outentisiteit geevalueer kan word. Die moontlikheid dat die "essensiestruktuur van behoorlike volwassenewees en van opvoedingsdoel" (ES) hieraan voldoen, is ondersoek. Die genoemde essensiestruktuur (ES) is in 'n modeldiagram CESM) saamgevat. Dit bevat die volgende essensies: 'religiositeit', die 'etiese', 'affektiwiteit', 'liggaamlikheid'. 'nasionaliteit' (insluitende 'kulturaliteit'. 'historisiteit' en die 'politiese'), die 'estetiese'. 'individualiteit'. 'sosialiteit'. die 'ekonomiese'. 'vryheid'. 'gesag'. 'taal' en 'redelikheid'. asook die sewe normbeelde wat 'n substruktuur van die 'etiese' is. 'Religiositeit' is hierargies die mees belangrikste essensie. gevolg deur die 'etiese'. Aldie ander essensies verkeer op 'n derde niveau van belangrikheid. Om outentiek te wees behoort 'n opvoedingseksemplaar aan boge noemde hierargie te voldoen. Elk van die genoemde essensies is verduidelik, asook hulle samehangende verbandhoudendheid binne die ESM. Die harmonie binne hierdie gestruktureerdheid is van deurslaggewende belang vir die begryping van outentisiteit by opvoeding. 'n Evalueringsmetode. bekend as ''essensiestruktuur-analise" (ES-analise). is uit bogenoemde deur die navorser ontwikkel. 'n Uiteensetting van mikro-. meso- en makro ES-analise is oak verstrek. Beskrywings van eksemplare van opvoeding en van aanverwante opvoedingsaangeleenthede word in die lig van die ESM geanaliseer. Hoe meer 'n opvoedingseksemplaar ooreenstem met die ESM hoe nader beweeg dit aan outentisiteit. en omgekeerd. Ter illustrasie van die toepassingsmoontlikhede van ES-analise is die mensbeskouing van C.K. Oberholzer. die kindbeskouing van J.C. Coetzee. die Christelike lewensopvatting, die wereldbeskouing van Albert Schweitzer en die opvoedingsleer van die Klassisisme aan ES-analises onderwerp. Die Christelike lewensopvatting kon as outentiek geevalueer word, terwyl die mensbeskouing van Oberholzer. die kindbeskouing van Coetzee en die wereld beskouing van Schweitzer naby aan outentisiteit beweeg. Die opvoedingsleer van die Klassisisme vertoon heelparty essensie-diskrepansies. Die hipotese, dat ES-analise 'n betroubare evalueringsmaatstaf vir outentieke opvoeding kan wees, is bevestig. Derhalwe kon die aanwending vanESanalise oar 'n wye spektrum aanbeveel word. byvoorbeeld by histories opvoedkundige eksemplare, godsdienslere. skoolstelsels en meegaande kurrikula en by die ontwikkeling van opvoedingsprogramme. Die huidige opvoeding en kon temporere leefwyse kan in die toekoms verbeter word indien ES-analise daadwerklik toegepas sou word. / An effort was made to find a universally valid criterion to evaluate any education for authenticity. The "essence-structure of proper adulthood and of education-aim" (ES) was investigated in this regard. This essence-structure (ES) was condensed in a model diagram (ESM). It includes the fo 11 owing essences: · re 1 i gi ousness · , the · ethi ca 1 ' , · affec tiveness'. 'bodiliness'. 'nationality' ('culturality'. 'historicity' and the 'political'), the 'aesthetical'. 'individuality', 'sociality·. the 'economical'. 'freedom·. 'authority'. 'language' and 'rationality'. as well as the seven norm images - a substructure of the 'ethical'. Hierarchically 'religiousness· is the most important essence. followed by the 'ethical·. All other essences exist on a third 1 eve 1 of importance. To qualify as authentic an exemplar of education ought to comply with the above-mentioned hierarchy. Each of the essences and their interrelatedness within the ESM were discussed. The harmonious co-existence within this structuredness is of paramount importance in understanding educational authenticity. Emanating from the above-mentioned an evaluation method. known as "essence structure-analysis" (ES analysis). was developed. Micro. meso and macro-ESanalysis were also explained. Descriptions of exemplars of education and of educationally related matters are analysed using the ESM as the criterion. The more an exemplar corresponds with the ESM. the more it re sembles authenticity, and vice versa. To demonstrate the application potential of ES analysis C.K. Oberholzer's view of man. J.C. Coetzee's view on childhood. the Christian life-view. Albert Schweitzer's world-view and the educational doctrine of the Classicism were subjected toES analyses. The Christian life-view could be evaluated as authentic. while Oberholzer's view of man. Coetzee's view on childhood and Schweitzer's world-view are resembling authenticity closely. The educational doctrine of the Classicism revealed several essence discre pancies. (viii) The hypothesis. that ES analysis can be a reliable evaluation criterion for authentic education. was confirmed. It could thus be recommended that ESanalysis be implemented over a broad spectrum. for example when studying historico-educational exemplars. doctrines of religion. school systems and curricula and assisting in developing educational programs. The contemporary education and way of life can be ameliorated in the future if ES analysis is applied actively. / Educational Studies / D.Ed. (Philosophy of Education)

Seit den 90er Jahren ist die Wettbewerbsstruktur im europäischen Eisenbahngüterverkehr starken Veränderungen unterworfen. Die Auflösung staatlicher Monopole sowie die Öffnung nationaler Märkte implizieren einen intensivierten Wettbewerb, bieten jedoch gleichzeitig die Möglichkeit, sich über neuartige Formen der Allianzbildung Wettbewerbsvorteile zu sichern bzw. Eintrittschancen in neue Transportmärkte zu nutzen. Die Einführung wettbewerblicher Marktstrukturen im Eisenbahngüterverkehr betrifft einerseits die Schaffung gleicher Wettbewerbsvoraussetzungen im Verhältnis der Verkehrsträger untereinander (intermodal). Weiterhin steht die Einführung von Wettbewerb zwischen Eisenbahnverkehrsunternehmen im Vordergrund (intramodal). Die vorliegende Arbeit betrachtet Allianzmöglichkeiten entlang beider Dimensionen: im Mittelpunkt stehen Partnerschaften zwischen Eisenbahnverkehrsunternehmen und/oder intermodalen Partnern, die grundsätzlich auf die Gestaltung des intramodalen Wettbewerbs ausgerichtet sind. Aufgrund des Einbezugs intermodaler Partner, der vor dem Hintergrund integrierter Logistikketten immer bedeutsamer wird, gelangt die Perspektive der Beeinflussung des Wettbewerbs der Verkehrsträger untereinander mittels Allianzen ebenfalls in das Blickfeld der Untersuchung. Übergeordnetes Ziel der Arbeit stellt die Analyse des Allianzphänomens und die Systematisierung spezifischer Allianzmodelle im europäischen Eisenbahngüterverkehr vor dem Hintergrund der sich fortlaufend verändernden Marktstruktur und fortgesetzten Deregulierung dieser Branche dar. Das Hauptinteresse gilt der Allianzrelevanz in dieser Branche im allgemeinen und der Verdeutlichung branchenstrukturprägender Allianzmuster im besonderen. Betriebswirtschaftlicher Forschung in diesem Branchenumfeld soll damit ein stärkeres Gewicht beigemessen werden.

本研究採用台灣教育長期追蹤資料庫(TEPS)的調查結果，對當前台灣地區國中生家庭教育資源組成結構進行次級資料分析，並探討家庭教育資源與學生學業表現之間的關連性。本研究目的在對家庭教育資源概念提出一探索性概念模型，並經由結構分析的方式，探討家庭教育資源的組成面向之內部結構組成。經由類型學的分析方法，本研究企圖區分出家庭教育資源弱勢與優勢的不同類型，並進行不同類型之間與學業表現的比較。結果發現家庭教育資源的弱勢類型與優勢類型彼此之間的在學業表現上的確存有明顯差異。因此分析結果也驗證了本研究所提出之模型架構與學業表現之間的關連性。 本研究將家庭教育資源區分為經濟性資源與非經濟性資源等二個理論面向，進一步將經濟性資源區分為顯性經濟資源與隱性經濟資源等二個次要面向；而非經濟性資源區分為家庭組成型態、家庭成員互動、家長教育參與、以及家長教育職業等四個次面向。本研究在方法論上採取近似性結構分析方法對各個不同次面向的組成結構進行資源結構近似性之分析。透過結構近似性分析本研究發現不同的家庭教育資源之內部組成結構的確存在某些近似性類型。同時研究探討不同家庭教育資源結構組成類型與學業表現之間的關連性，茲將研究發現摘要如下： 一、家庭居住安排的不同類型中，家長是否缺位為最重要的居住安排類型；且家長是否缺位與學業表現有明顯的關連性存在。同時家庭子女數太多對學業表現也有不利影響。 二、家庭成員互動與學業表現有密切的關係，尤其是家長採取的不同管教方式與學業表現有關；同時親子之間不同的衝突型式所代表的資源性意義並不相同。 三、家長不同的教育參與對子女學業表現影響有所不同，家長在家庭內的教育參與行為與子女的學業表現有關；家長對子女的教育期望與子女的學業表現有明顯的關連；而家長對學校活動的參與在本研究中並未發現與子女學業表現有明顯相關。 四、家長教育職業背景與子女學業表現有明顯關係，低教育職業背景對子女有不利的影響；而高教育職業背景與學業表現有正面關連性存在。 五、家庭經濟資源，不管是顯性或隱性資源，與學生學業表現有明顯關連性存在。家庭經濟情況較佳者，家庭投入較多的資源提供子女學習各種課外活動者對學業表現有較為正面向影響；而家庭經濟情況較差者與從未參加過任何課外學習活動者學業表現較差。 綜言之，本研究發現缺位型家庭、手足人數較多、家長採取較為忽略消極型的管教、親子之間發生外向性衝突、家長低教育職業背景、家庭經濟情況較差、以及家庭從未投入任何課外活動學習資源的學生為弱勢類型的學生；反之，完整型家庭、手足人數較少、家長採取較為積極關心管教、家長關心子女的學業及生活、家長教育職業背景較高、家庭經濟情況較佳、以及持續提供資源供給子女學習課外活動者為相對優勢的類型。同時，弱勢與優勢類型相較，前者明顯對學業表現有不利的影響。根據研究結論建議，相關的教育工作政策制定者及執行者，以及研究者應該投入更多的資源對家庭教育資源弱勢類型的學生進行補救及輔導，以達成社會正義的目標。 除了發現家庭教育資源與學業表現之間的關連性外，本研究在方法論上也突破先前研究對於資料測量層次造成的限制，嘗試經由近似性結構分析的方法，對類別性的資料進行類型學的分析，從而擴大了不同的資料分析方法及概念建構的可行性。 / This study analyzes the constitution structure of family educational resources of Taiwan arena Junior High School students and its connection with academic achievement of students. The secondary data is adapted from Taiwan Education Panel Survey (TEPS). The goal of this study is to propose an explorative conceptual framework of family educational resources, and investigate the internal constitution structure of its different constitutional dimensions. This study tries to distinguish the relative advantage and disadvantage types of family educational resources by typology method and make a comparison on academic achievement between these different types. The results show that there are significant differences between the advantage and disadvantage types on academic achievement. Accordingly, the results support our proposed model and its connection with academic achievement of students. This study divide family educational resources into two different theoretical dimensions: economic and non-economic resources and subdivide the economic resources into two sub-dimensions of apparent and unapparent resources; subdivide the non-economic resources into four sub-dimensions of family constitution structure, family member interaction, parents involvement, and parents’ education and occupation. The methodology of this study is to analyze the constitutional structures of these sub-dimensions by proximities structure analysis. The results show that there are similarities structure patterns within the constitutional structures of family educational resources. Meanwhile, the results show that there are connections between the different types of family educational resources and academic achievement. Author summarizes the findings as follows: 1. The different types of residential arrangements, the absence of parents is a very crucial type and is very obviously connection with academic achievement. The number of siblings is also crucial to academic achievement. 2. Family members’ interaction is crucial to academic achievement; especially the discipline styles of parents are influential to achievement of their children; meanwhile, the different conflict types of parents and children are very different resources meanings per se. 3. The different educational involvement behaviors are influential to children’s academic achievement, but it depends on the types of behaviors. Parents’ educational involvements within family are influential to children’s achievement; parents’ education expectations to their children are influential to their children; parents’ involvements with school are not found significant connections with academic achievement. 4. The education and occupation backgrounds of parents are found to be a very crucial factor to their children’s achievement, low level background is negative to achievement, and high level background is positive to achievement. 5. Family economic resources whichever apparent or unapparent are crucial to children’s achievement. Those who are richer and invest more resources on extraclass learning are found positive correlation with achievement; those who are poorer and never invest any resources on extraclass learning are found negative correlation with achievement. To summarize, our research found that those who are parent absence, the number of siblings are more than three, parent’s discipline style is negative and ignored, extrovertive conflict between parents and children, low level of parents’ education and occupation background, the poor and the family never invest any resources on extraclass learning are the disadvantage type; in contrast, those who are parent are not absence, the number of siblings are less than two, parent’s discipline style are positive and concerned, parents concern about children’s learning, high level of parents education and occupation background, the richer and invest more on extraclass learning are advantage type. The two different types of family educational resources are different on academic achievement. The performances on academic achievement of the advantages are better than the disadvantages. For the ultimate goal of social justices, results suggest that the educational policy makers, the teachers and researchers should invest more resources on the disadvantages. In additions, this study penetrates the limitations of data measurement level which distract earlier researchers. By proximities structures analysis method, we analyze the categorical data with typology methodology, and enlarge the landscape of secondary data analysis and possibilities of construction of conceptual frameworks.

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We look at the underlying friendships and relationships between Chinese Internet users. We identify the presence and characteristics of the different types of online friendships and online relationships by analyzing various online social networks. First, we look at the concept of guanxi as it is applied to the interaction between web sites. Guanxi is a type of dyadic social interaction based on feelings and trust which has been well studied by scholars in China. We define guanxi in the web: particular linking patterns that appear in the web as well as supporting textual evidence in the web pages which we believe are indicative of the presence and varying strengths of the underlying guanxi between Chinese web site owners. Through our empirical study of the Chinese web, the general web, and the Japanese, Iranian, and French web, we show that guanxi between web sites is a more prevalent feature in the Chinese web. Next, we study the formation of online friendships in Douban, an online social networking platform frequently used by the youth in China. We look at several factors that can affect the evolution of friendships such as having memberships in the same discussion groups and sharing common interests or common friends. We compare these factors in influencing the formation of online friendships. Our work provides the first study on the underlying relationships between web sites in the Chinese web and the first large scale empirical analysis on the evolution of friendships in a Chinese online social network.

Cette contribution, en s’appuyant sur expérimentation et modélisation numérique vise à une meilleure compréhension du comportement des dalles en béton armé sous sollicitations de cisaillement. Une campagne expérimentale a été réalisée sur des dalles épaisses à pleine échelle de centrales nucléaires. Ces dalles sans armatures d’effort tranchant sont soumises à une sollicitation de cisaillement en chargement quasi-statique. Les essais sont réalisés en faisant varier différents paramètres qui peuvent influencer le comportement au cisaillement. Sont ainsi étudiés : résistance en compression du béton, épaisseur, taux d’armatures longitudinales et transversales, taille des granulats, longueur de la plaque de chargement. L’influence des efforts de membrane, de compression ou de traction, sur le comportement au cisaillement a également été analysée. Les résultats des essais sont ensuite comparés aux prédictions des codes de calcul. Ces résultats ont d’abord permis d’apporter une réponse aux divergences qui existent entre l’Eurocode 2 et l’Annexe Nationale Française quant à la prédiction du cisaillement. Ont également été évalués le niveau de précision donné par d’autres normes de dimensionnement au cisaillement: la norme américaine ACI 318-14, le code nucléaire AFCEN ETC-C 2010, le fib-Model Code 2010 et l’approche par la théorie de la fissure critique de cisaillement CSCT. Ensuite est évalué la possibilité d’analyses non-linéaire par élément finis (EF) pour reproduire le phénomène du cisaillement dans les dalles. Un modèle de béton élastoplastique avec endommagement est combiné à une analyse quasi-statique à schéma de résolution explicite. Des lois de comportement non linéaires appropriées du béton avec des comportements post-pic associés à un critère énergétique ont été considérées. La bonne concordance entre le modèle proposé et les résultats expérimentaux en termes de résistance au cisaillement et de modes de rupture permet de valider la modélisation proposée. Une étude paramétrique a été réalisée sur la base du modèle proposé avec les mêmes propriétés mécaniques de béton. Des lois simplifiées permettant d’estimer les capacités en cisaillement en fonction des différents paramètres étudiés sont finalement proposées. / This study, based on experiments and numerical modeling, aims at a better understanding of the shear behavior of reinforced concrete slabs. An experimental campaign was carried out on full-scale thick slabs typical of nuclear power plant slabs. These slabs without shear reinforcement are subjected to a quasi-static shear loading. The tests are carried out by varying different parameters that can influence the shear behavior: the concrete compressive strength, the slab depth, the bottom longitudinal and transverse reinforcement ratio, the concrete aggregate size, the loading plate length. The influence on shear behavior of compression or tension membrane forces has also been analyzed. The results of tests are then compared with the predictions of the calculation codes. These results first of all helped to answer the differences between the Eurocode 2 and the French National Annex concerning the prediction of the shear capacity of reinforced concrete slabs. The level of accuracy given by other shear dimensioning standards was also assessed: The American standard ACI 318-14, the AFCEN ETC-C 2010 code used for nuclear buildings, the fib-Model 2010 and the Critical Shear Crack Theory. Next, we evaluate the possibilities of a non-linear finite element analysis (EF) to reproduce the phenomenon of shear in slabs. An elastoplastic concrete model with damage was used and combined with a quasi-static analysis using an explicit resolution scheme. Appropriate nonlinear behavior laws of concrete with post-peak behaviors associated with an energy criterion were considered. The good agreement between the proposed model and the experimental results in terms of shear strength and failure modes allowed validating the proposed modeling. A parametric study was conducted based on the numerical proposed model with the same mechanical properties of concrete. Simplified laws allowing estimating the shear capacities according to the different parameters studied are proposed.