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321.
    
The concept of base isolation is a century old, but application to civil engineering structures has only occurred over the last several decades. Application to light-frame wood buildings in North America has been virtually non existent with one notable exception. This article quantitatively examines issues associated with application of base isolation in light-frame wood building systems including: (1) constructability issues related to ensuring sufficient in-plane floor diaphragm stiffness to transfer shear from the superstructure to the isolation system; (2) evaluation of experimental seismic performance of a half-scale base-isolated light-frame wood building; and (3) development of a displacement–based seismic design method and numerical model and their comparison with experimental results. The results of the study demonstrate that friction pendulum system (FPS) bearings offer a technically viable passive seismic protection system for light-frame wood buildings in high seismic zones. Specifically, the amount and method of stiffening the floor diaphragm is not unreasonable, given that the inter-story drift and accelerations at the upper level of the tested building were very low, thus resulting in the expectation of virtually no structural, non structural, or contents damage in low-rise wood frame buildings. The nonlinear dynamic model was able to replicate both the isolation layer and superstructure movement with good accuracy. The displacement-based design method was proven to be a viable tool to estimate the inter-story drift of the superstructure. These tools further underscore the potential of applying base isolation systems for application to North America's largest building type.  相似文献   
322.
    
In this article, one of the procedures proposed in literature for the design of viscous dampers to be inserted in existing buildings is examined and extended to 3D eccentric buildings. The proposed procedure has been verified through a case study characterized by a six-story RC building. Both plan-symmetric and plan-asymmetric configurations have been considered for comparisons. The effect of considering the plan-asymmetry in the design has been studied. Moreover, also the importance of considering the higher modes has been investigated. The effectiveness of the design procedure has been then evaluated through the comparison with nonlinear dynamic analyses.  相似文献   
323.
    

This article analyses the inter-relationships among food consumption practices, marketers' representations of sugar, and the history and political economy of sugar production. It focuses on the 'supermarket narratives'--stories regarding place and production that appear on commodity packaging--used to market sugar in the USA. It explores how competition within the sweetener industry, as shaped by the material qualities of sweeteners, has given rise to supermarket narratives that seek to differentiate sugars on the basis of ideas of place, freshness and environmental sustainability. It also examines how, at the same time, sweetener users have co-operated to maintain and increase consumption in the USA. The article begins with a discussion of historical patterns of sweetener consumption in the USA, and then looks at the genesis of the primary sugar industry lobbying organization. The case study of Florida sugar producers is used to demonstrate the historical antecedents of supermarket narratives and the contemporary geographical specificity of the political economy underlying supermarket narratives.  相似文献   
324.
    
In this article, the influence of nonlinear behavior of multiple degree of freedom (MDOF) primary structures on floor response spectra is investigated by means of simple structural models. The cases of shear beam type as well as of capacity-designed plane frames were studied. It is shown that, in general, but not always, nonlinearity of the primary structure has a beneficial effect on floor spectra. However, higher mode response may be amplified due to nonlinear behavior. The issue of a one story structure exhibiting torsionnal response has also been addressed and some important properties are highlighted.  相似文献   
325.
    
Design as Mediating Interface: Historical Evidence and Symbolic Enunciation of the Radio Set. – Based on a case study on the invention of the radio station scale in the late 1920's and early 1930's, this article pleads for an interdisciplinary look at the importance of design as a mediating interface in the production‐consumption junction. In this cultural history perspective on technology, the material artifact matters both as a witness of and a sign for the symbolic meaning and appropriation of the technical object, which transgresses the functional logic of instrumental rationality. In presenting five different perspectives on design offering some alternative looks for a cultural history of technology, this theoretically inspired essay wants to sound the critical potential of a multilayered semantic approach to the radio apparatus as a prominent representation of a radical innovation in media technology.  相似文献   
326.
Abstract

In accordance with international conventions the Sámi is an indigenous group belonging to two populations and two overlapping civil societies within one nation state. This situation not only influences Sámi political interests and activities in general, but it also affects the individual Sámi's political orientation and decisions. Nevertheless, no thorough study has been conducted, on the individual level, of Sámi political participation and involvement. We know neither how political attitudes and participation vary within this group, nor how it varies in relation to the Norwegian population in general. Thus we know practically nothing about how recent institutional developments have influenced Sámi citizenship.

This article looks closely at variations in political involvement and participation amongst Sámi and non-Sámi living in Norway's Sámi language management area, and compares this with political involvement and participation amongst the Norwegian population in general. The Citizenship Survey shows that in terms of political interest and participation, the Sámi living in the Sámi language management area are on par with others living there, and with Norwegians in general. In several important political areas the Sámi actually show significantly more interest and involvement than Norwegians in general. Furthermore, Sámi political trust and self-confidence are as high as in the general population, and we have not uncovered any particular marginalisation with respect to women and young people's interest and participation.

There is much to suggest that our findings measure not only the Sámi's combined political interest and participation, but also their degree of participation and interest in the Norwegian political system. We do not find a picture of Sámi political segregation, nor of an extensive marginalisation. The findings point towards strong integration in the Norwegian political system, with Norwegian and Sámi public space and civil societies overlapping rather than being competitive or even antagonistic.  相似文献   
327.
    
How does violent conflict affect social and political attitudes? To answer this question I pair Kenyan survey and violence data for the time period following the country's December 27th 2007 national election. I find that respondents who personally experienced electoral violence are less likely to express certain forms of inter-personal and institutional trust than those individuals who did not. The association is not universally powerful, however. First, noteworthy differences emerge between populations who relocated as a result of post-election conflict and those who did not. Differences between these groups suggest that internal migration in the wake of tragedy influenced the Kenyan social landscape. In addition to personal exposure to electoral conflict, I test how local level violence may indirectly condition Kenyan political attitudes. Across all models, individual-level exposure to violence has the most consistent influence upon opinions, although district level effects emerge in analyses without survey respondent ethnicity controls. This finding suggests that living in a setting of regional insecurity does not have as important an effect on certain political views as personal victimization.  相似文献   
328.
    
This article focuses on the optimum design of bridge abutments when subjected to earthquake loading. Planar failure surface has been used in conjunction with modified pseudo-static approach to compute the seismic active earth pressures on an abutment. The proposed modified Mononobe-Okabe method considers the effects of strain localization in the backfill soil and associated post-peak reduction in the shear resistance from peak to residual values along a previously formed failure plane, phase difference in shear waves, and soil amplification along with the horizontal seismic accelerations. Four modes of stability viz. sliding, overturning, eccentricity, and bearing capacity of the foundation soil are considered in the analysis. The influence of various design parameters on the seismic stability of abutments is presented. The optimum values of base width of the abutment needed to maintain the stability are obtained against four modes of failure, based on the suggestions of Japan Road Association, Caltrans Bridge Design Specifications, and U.S Department of the Army.  相似文献   
329.
The problem of multi-objective seismic design optimization is examined within the context of passive energy dissipation systems. In particular, a genetic algorithm approach is developed to enable the evaluation of the Pareto front, where maximum inter-story drifts and maximum total accelerations, both important measures for damage, serve as objectives. Here the cost of the passive system is considered as a constraint, although it could be included instead as a third objective. Hysteretic, viscoelastic and viscous dampers are all considered as possible design strategies, as well as the weakening plus damping concept. Since different types of passive systems are included, diversity of the Pareto front becomes a key issue, which is addressed successfully through an innovative definition of fitness. The multi-objective framework enables the evaluation of trade-offs between the two objectives and, consequently, provides vital information for the decision maker. Furthermore, the results presented offer valuable insight into the characteristics of optimal passive designs for the different objectives. Some of these characteristics confirm results reported elsewhere, while others are presented here for the first time.  相似文献   
330.

During the 1990s scholars began to identify and study social movements organized to confront the 'new global order'. Such movements have emerged in Mexico, Japan, South Africa and the USA. In the emerging literature organized to study these movements scholars have noted two characteristics that hold constant across them. First, while such movements oppose globalization, they tend to focus their criticism against their own governments for ushering in its reforms. Second, while the state is regarded as the enemy, these movements frame their politics against the state in nationalistic terms. In this paper we compare and evaluate the projects of 'national' resistance in two social movements against the new global order--the Mexican Zapatista and the US Patriot Movements. To conduct our analysis we employ a post-structuralist approach. We argue that the category of nation is constructed and may take any number of forms, from the liberatory to the repressive. As such, we hold that the best way to evaluate nationalistic projects is to assess whether antagonism infuses constructions of 'nation' and its spatial policing. In our empirical analysis we argue that the nationalistic discourse of Zapatismo, though not without problems, is agonistically constructed, creating a plural space for nation re(building). In contrast, discourses of patriotism are antagonistically defined, fostering exclusive views of nation and a rigid policing of its borders. We conclude by noting potential pitfalls in the Zapatista identity politics and potential progressive openings within the Patriot identity politic. Au cours des années 1990, des chercheurs ont identifié et étudié différents mouvements sociaux qui cherchent à confronter le 'nouvel ordre global'. De tels mouvements ont émergé au Mexique, au Japon, en Afrique du Sud et aux États-Unis. Dans leurs travaux publiés sur ce récent phénomène, les scientifiques ont noté deux traits caractéristiques de ces mouvements. Premièrement, malgré qu'ils s'opposent à la mondialisation, ils ont tendance à diriger leur critique envers leur propre gouvernement qui ouvre la porte à des réformes globalisantes. Deuxièmement, alors que l'état est considéré comme étant l'ennemi, ces mouvements encadrent leurs politiques contre celui-ci selon des termes nationalistes. Dans cet article, nous comparons et évaluons les projets de résistance 'nationale' de deux mouvements sociaux contre le nouvel ordre global: le mouvement Zapatiste au Mexique et le mouvement Patriote aux États-Unis. Une approche post-structuraliste est utilisée dans notre analyse. Nous soutenons que la meilleure façon d'évaluer des projets nationalistes est de juger si les concepts de 'nation' et sécurité du territoire sous-entendent une perspective antagoniste. Dans notre analyse empirique, nous soutenons que le discours nationaliste des Zapatistes, même s'il demeure problématique, s'élabore selon une perspective 'agoniste' favorisant l'ouverture d'un espace pluraliste pour re(construire) la nation. Par contraste, les discours du patriotisme présentent un point de vue antagoniste encourageant une vision exclusive de la nation et du contrôle de ses frontières. Nous concluons en notant les pièges potentiels du discours identitaire Zapatiste et les ouvertures progressistes possibles au sein de son homologue Patriote. Durante los años noventa los especialistas empezaron a identificar y estudiar movimientos socials, organizados con el fin de enfrentarse con el 'nuevo orden global'. Estos movimientos han surgido en México, Japón, Africa del Sur y en los Estados Unidos. En la literatura que estásaliendo para estu diar estos movimientos los especialistas han notado que hay dos características que todos tienen en común. Primero, aunque estos movimientos se oponen a la globalización, tienden a criticar sus própios gobiernos por haber introducido las reformas. Segundo, aunque el estado es considerado el enemigo, estos movimientos construyen sus políticas contra el estado en términos nacionalistas. En este papel comparamos y evaluamos los proyectos de resistencia 'nacional' en dos movimientos sociales contra el nuevo orden global: el Zapatista de México y el 'US Patriot Movement' (Movimiento Patriota de Estados Unidos). Abordamos el análisis empleando un método pos-estructuralista. Sugerimos que la categoría de nación es construída y puede manifestarse de varias formas; de liberatoria a represiva. Por lo tanto, creemos que la major manera de analizar los proyectos nacionalistas es de evaluar si el antagonismo infunde construcciones de 'nación' y su orden espacial. En nuestro análisis empírico sugerimos que el discurso nacionalista del zapatismo, aunque no carece de problemas, es construído del punto de vista agnóstico y, por lo tanto, crea un espacio plural para la (re)construcción de la nación. Al contrario, los discursos sobre el patriotismo se definen de manera antagonística, la cual promueve puntos de vista exclusivos de lo que es la nación y promueve la rígida vigilancia de sus fronteras. Concluímos por mencionar las posibles desventajas de la política de identidad zapatista y las posibles aperturas dentro de la política de identidad Patriota.  相似文献   
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