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从1841年2月26日巴麦尊训令乔治.懿律促使中国解除鸦片禁令开始,一直到1858年11月8日中英两国代表签署《通商章程善后条约:海关税则》正式承认鸦片贸易合法化为止,英国的这一外交图谋的最终实现经历了将近18年的时间。通过系统阅读英国议会文件,并参考中文档案资料,我们可以很清楚地看到,参与向中国官员施加压力的英国官员中,既有英国首相,又有外交大臣;既有英国驻华公使、商务监督,又有驻广州、厦门和上海的领事官。由此可见,逼迫清朝官员承认鸦片贸易合法化是19世纪中叶英国政府既定的一贯坚持的对华外交方针和政策。  相似文献   

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In input-output analysis there are two alternate possibilities between Leontief's mechanism (fixed technical coefficients) and Ghosh's mechanism (fixed allocation coefficients). Testing the long-term consistency of these mechanisms entails comparing input-output matrices over time. This paper challenges the value of proportional filters (separate comparisons of column and row coefficients) and introduces the biproportional filter that allows simultaneous comparison of column and rows. An application is proposed using French input-output tables for 1980 and 1993. The stability of column coefficients cannot be taken for granted and, generally, for any sector, both row and column coefficients are found to change simultaneously.  相似文献   

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The evolution of techniques to manage patients with head injuries has served as the basis for the treatment of other neurosurgical disorders, including brain tumors, intracranial infections, and cerebrovascular disease. In the nineteenth century, advances in anesthesia, asepsis, and cerebral localization slowly took hold and created the groundwork for modern neurosurgery. To better understand the advances in the treatment of brain injuries in the late 1800s and early 1900s, we examine relevant historical literature and, through the courtesy of the Alan Mason Chesney Medical Archives, we review Dr. Harvey Cushing's patient records (1898–1909) in the Johns Hopkins Hospital surgical archives. The original case histories of 10 patients (6 in detail) who suffered head injuries and underwent treatment by Cushing illustrate some of Cushing's early attempts at intracranial surgery. We also examine the influences on Cushing as he developed into a leader in the new era of modern neurosurgery.  相似文献   

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清乾隆年间,迁居伏尔加河流域已有百余年的土尔扈特部众东归,清廷以分散安置为原则,对土尔扈特部众进行了安置,其中直属其首领渥巴锡的部众,被指地安置于天山北部的斋尔地方。但寒冷的侵袭、病魔的肆虐、物资的匮乏和农牧不旺,迫使渥巴锡不得不提出另行选址迁移。时任伊犁将军的舒赫德经派人勘查,将渥巴锡部众尽数移至天山南部的珠尔都斯草原,完成了土尔扈特部众万里东归后的一次大动迁。  相似文献   

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Public confidence in the police is crucial to effective policing. Improving understanding of public confidence at the local level will better enable the police to conduct proactive confidence interventions to meet the concerns of local communities. Conventional approaches do not consider that public confidence varies across geographic space as well as in time. Neighborhood level approaches to modeling public confidence in the police are hampered by the small number problem and the resulting instability in the estimates and uncertainty in the results. This research illustrates a spatiotemporal Bayesian approach for estimating and forecasting public confidence at the neighborhood level and we use it to examine trends in public confidence in the police in London, UK, for Q2 2006 to Q3 2013. Our approach overcomes the limitations of the small number problem and specifically, we investigate the effect of the spatiotemporal representation structure chosen on the estimates of public confidence produced. We then investigate the use of the model for forecasting by producing one‐step ahead forecasts of the final third of the time series. The results are compared with the forecasts from traditional time‐series forecasting methods like naïve, exponential smoothing, ARIMA, STARIMA, and others. A model with spatially structured and unstructured random effects as well as a normally distributed spatiotemporal interaction term was the most parsimonious and produced the most realistic estimates. It also provided the best forecasts at the London‐wide, Borough, and neighborhood level.  相似文献   

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This article presents a hierarchical flow capturing location problem (HFCLP) and proposes an effective Lagrangian heuristic solution method. The original flow capturing location problem (FCLP) aims to locate a given number of facilities on a network to maximize the total flow that can be serviced at facilities along their preplanned routes, such as daily commute to work. We extend the original model to allow a decision maker to select the size of facilities among m different size alternatives. Larger facilities are assumed to be more attractive and, therefore, can attract more customers, but they cost more to construct than smaller ones. Customers deviate from their preplanned routes to access a facility's service when the size of the facility is sufficiently large. The degree of deviation from the original path is measured by the additional distance customers have to go to access facilities, and the acceptable deviation distance becomes larger as the size of a facility increases. This article presents a new problem in which the number of facilities of each size and their locations are simultaneously determined so as to capture as much flow as possible within the total budget available for locating all facilities. We present an integer programming formulation of the problem and devise a Lagrangian relaxation solution method. The proposed algorithm is tested using road networks with 300 and 500 nodes. The results show that the method produces high‐quality solutions in a fairly short time. Este artículo presenta un problema de localización de captura de flujo jerárquico (hierarchical flow capturing location problem‐HFCLP) y propone un método heurístico eficiente de tipo Lagrange (lagrangian). En su formulación original el HFLCP tiene como objetivo localizar un número determinado de instalaciones en una red con el fin de maximizar el flujo total que puede ser atendido por las instalaciones existentes a lo largo de rutas preestablecidas, como en el caso por ejemplo, de los desplazamientos diarios del lugar de residencia al de trabajo. Los autores amplían el modelo original para permitir que el tomador de decisiones seleccione el tamaño de las instalaciones entre “m” alternativas. Se asume que las instalaciones más grandes son más atractivas que las más pequeñas y, por lo tanto, pueden atraer a más clientes, pero a la vez, son también más costosas de construir. Los clientes se desvían de su ruta preestablecida para acceder al servicio de una instalación cuando el tamaño de la instalación es lo suficientemente grande. El grado de desviación de las rutas se mide por la distancia adicional que los clientes viajan para acceder a las instalaciones. La distancia de desviación aceptable se hace más grande en relación al tamaño de la instalación. En este artículo se presenta un nuevo modelo para el HFLCP en el que el número de las instalaciones de cada tamaño y su ubicación son determinadas simultáneamente con el fin de capturar la mayor cantidad de flujo dentro del presupuesto total disponible para la localización de todas las instalaciones. Los autores presentan una formulación de programación entera (integer programming) del HFCLP e implementan un método que relaja la solución lagrangiana. El algoritmo propuesto es evaluado utilizando redes viales con 300 y 500 nodos. Los resultados muestran que el nuevo método produce soluciones de alta calidad y en tiempos de computación relativamente cortos. 本文介绍了一种分层的截流选址问题 (HFCLP),提出了一个有效的拉格朗日启发式解决方法。最初的截流选址问题(FCLP)目标是在网络上布局给定数量的设施使总流量最大,使按预定路线的行进流可以获得最大的服务,如每日的工作通勤。本文对原始模型进行扩展,让决策者可在不同的设施规模选择方案中进行规模选择。假设更大规模设施具有更大的吸引力,因此也能够吸引更多的客户,但同时也需要更多的建造成本。当设施规模足够大时,消费者会选择偏离预定路径而进入该设施的服务范围。对原始路径的偏离程度可通过用户进入该设施所增加的额外距离度量。可接受的偏差距离随着设施规模增大而增大。本文提出了在总预算确定条件下,同步确定不同规模设施数量及其位置以实现截取最大流量的新问题,并给出了该问题的整数规划方法,设计了拉格朗日松弛解法。通过300和500个节点的网络测试,结果显示该算法可在相当短时间内获得高质量的解决方案。  相似文献   

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In a previous issue of Irish Studies Review I examined the unanticipated emergence in the late 1980s of a series of Conservative associations in Northern Ireland. In this follow-up article, I will seek to account for the subsequent swift and ignominious decline in the early 1990s of the Northern Irish Conservatives. While the fortunes of the Ulster Tories were undermined by a number of contingencies – the vagaries of parliamentary arithmetic and their own lack of political judgement foremost among them – their fate was sealed primarily by certain rather more structural concerns. In particular, the rapid decline of the Conservative associations in Northern Ireland owes its origins to the historically “loveless marriage” between Ulster unionists and the British state. The unionist community simply refused to vote in meaningful numbers for a political party at the centre of a Westminster establishment deemed hostile to the cause of the Union. In addition, the Conservative hierarchy would inevitably prove unwilling to nurture their own party associations in Northern Ireland as this “integrationist” project ran precisely counter to their own longstanding political ambitions for the region. This conflict of interests and intentions would in short order ensure the demise in all but name of the Northern Irish Conservatives. There can be few more dramatic illustrations of the mutual distrust that conjoins Ulster unionists and the British state than the string of lost deposits incurred by Conservative candidates running for office in Northern Ireland.  相似文献   

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The characteristics of hierarchical trade flows, when placed in the context of differentiated markets, can provide some insight into the underlying bases of contemporary international trade. A model that relies on differentiated market theory and hierarchical market theory is developed. Trade characteristics derived in the model, concerning the frequency and value of trade, are empirically tested. Empirical results indicate that the model provides a useful framework for the analysis of contemporary international trade.  相似文献   

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