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1.
丁晓杰 《史学月刊》2007,(10):73-80
日本树立伪蒙疆政权后,为了掠夺该地区丰富的畜产资源,实行畜产统制政策。羊毛统制是畜产统制的核心,即对绵羊的增产改良、羊毛的收购、对外输出等,实行强制性的政府指导、控制措施。其中,绵羊改良是羊毛统制政策的重点之一。为了获取重要战略资源羊毛,日本将该地域作为大陆绵羊改良的基地,通过伪蒙疆政府、日系企业、蒙古绵羊协会等组织对肉、皮兼用型的蒙古原种绵羊进行改良,实质是为日本的对外侵略扩张提供羊毛这一急需的战略资源。  相似文献   
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Jacop Custodi elaborated recently a response to our article “A nationalist party with non-nationalistic voters? Discussing the limits of nationalism in party categorisation” published in the journal Nations & Nationalism. We consider the work of Custodi is an important and original contribution to the study of left politics and nationalism. This being said, we reflect on the negative consequences of overstretching the category nationalism, both referring to parties and to political discourse. The aim of this reply is unpacking and explaining these negative consequences and offering an alternative as well as responding to some specific points raised by Custodi in his reply.  相似文献   
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The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
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In this paper, we develop a three-region economic geography model with workers of heterogeneous skills and mobility rates to consider how first-nature, regional differences impact both inter- and intraregional inequality. In our model, the skill premium within a region summarizes both the degree of intraregional inequality between mobile, skilled workers and immobile, unskilled workers and the interregional inequality through differences in the welfare of unskilled workers across regions. Regions with the highest skill premium have the greatest degree of intraregional inequality and provide the lowest level of welfare to unskilled workers, relative to other regions. We find that the skill premium will be higher in regions with a greater supply of unskilled labor, lower supply of housing, or are more remote. An increase in a region's housing supply or centrality will lower intraregional inequality and raise the welfare of the local, unskilled workforce. However, the magnitude of these changes are declining in the initial number of skilled workers in the region. The model is extended to consider imperfectly elastic housing supply. The larger the price elasticity of housing, the larger the range of values, such that more populated regions will host a disproportionate share of skilled workers, have lower levels of intraregional inequality, and provide higher levels of welfare for unskilled workers.  相似文献   
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This article presents a Bayesian method based on spatial filtering to estimate hedonic models for dwelling prices with geographically varying coefficients. A Bayesian Adaptive Sampling algorithm for variable selection is used, which makes it possible to select the most appropriate filters for each hedonic coefficient. This approach explores the model space more systematically and takes into account the uncertainty associated with model estimation and selection processes. The methodology is illustrated with an application for the real estate market in the Spanish city of Zaragoza and with simulated data. In addition, an exhaustive comparison study with a set of alternatives strategies used in the literature is carried out. Our results show that the proposed Bayesian procedures are competitive in terms of prediction; more accurate results are obtained in the estimation of the regression coefficients of the model, and the multicollinearity problems associated with the estimation of the regression coefficients are solved.  相似文献   
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The period comprising the end of the Early Neolithic and the Middle Neolithic, dated broadly within the fifth millennium cal BC, corresponds to an interval that remains largely unknown in the extreme north-western tip of Africa. This situation contrasts with that of the Early Neolithic, a period characterised by the earliest evidence of the diffusion of a productive economy, cultivated plants and domestic animals. The paucity of data for these later phases can be explained in part by the lack of secure contexts and sequences based on radiocarbon datings of short-lived samples. The current study presents the results of the excavations of El-Khil Caves B and C that yield materials allowing re-evaluation of the chronology of a type of ceramic known as Ashakar ware. The study also identifies two traditions in the northern Moroccan Middle Neolithic. The first is heir to the so-called Impressa Mediterranean ware and rooted in the Cardial Neolithic, while the second is characterised by roulette cord impressions, red slip and tunnel lugs and probably rooted in the region of the Sahara, and has no technological precedents in the study area.  相似文献   
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西塞罗是古罗马著名政治家。在罗马共和末期动荡不安的派系斗争中,西塞罗代表元老贵族派的利益,以维系传统的以元老院为核心的共和体制为己任,与形形色色试图颠覆罗马共和政体的野心家进行了坚决的斗争,被誉为"共和国之父",可谓风光无限。然而,特殊的政治环境,残酷的派系斗争导致西塞罗在长达30余年的政治生涯中不断变换政治立场,深深地卷入派系斗争,并在其中发挥了举足轻重的作用,最终沦为派系斗争的牺牲品。  相似文献   
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Most quantitative approaches to distributional analysis in archaeology assume a homogeneous study surface that is amenable to easy generalisations. This framework has been widely used to describe settlement processes, disregarding the spatial heterogeneity inherent to geographic reality. In other words, researchers have often assumed that the correlation between the elements of a spatial distribution is a function of the Euclidean distance (i.e. straight line distance) between them. Other archaeological studies have tested alternative measures to Euclidean distances, such as cost-based ones, both to describe optimal routes and to assess spatial autocorrelation in a point pattern. Nevertheless, until now there has been no suitable model to introduce these measures into spatial statistical equations. In order to overcome this obstacle, we approach the implementation problem inversely by embedding the spatial pattern under study into a Euclidean frame of reference based on its cost-distance pairwise matrix. This paper describes the application of this methodology on one of the main tools used by archaeologists to assess settlement patterns: Ripley’s K function. We present two case studies, covering both macroscale and mesoscale, with significant variations in the results depending on the use of the Euclidean or cost-based approach. Data, functions and results have been R-packaged for the sake of reproducibility and reusability, allowing other researchers to build upon our methods.  相似文献   
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