中国大城市贫困研究的多种测度与多层模型分析

基于六大城市住户调查数据,采用多种贫困测度和多层模型分析的方法,探讨中国大城市居民贫困状况及其影响因素。研究发现,大城市低收入邻里的贫困状况存在较大差异,其中广州、西安的相对丢失(relative deprivation)严重且低收入群体层级结构复杂,昆明的贫困深度大,而武汉财富集聚相对明显。贫困多层模型表明低收入邻里贫困的主要影响因素仍存在于个体层面,个体在家庭制度、市场制度、国家福利供应中所表现的特征影响了贫困发生率;城市贫困同时存在邻里效应,主要体现在邻里经济状况和贫困文化的影响作用;而城市间的贫困差异亦不可忽视。     

环境管制措施对区域环境与贸易的约束效应

环境管制是指各国在国际贸易中为了实现环境与贸易的协调关系,以环保为目的而采取的贸易限制措施,主要包括课征环境进口附加税、限制或禁止进出口、推行国内加工和生产方法、实行环境标志制度、政府环境补贴等5种类型。本文总结了在全球化背景下环境管制措施产生的原因及施行内容,在此基础上就其对区域环境与贸易的约束效应做了分析,旨在为我国突破\"绿色壁垒\"提供警示和借鉴。     

过滤理论的起源、概念及研究进展

过滤是住房的生命周期与家庭的生命周期之间相互作用的产物,包括两大支流:以建立经济理论和模型为代表的关注住房的过滤研究、有关居民迁居的强调家庭的过滤研究。过滤理论的地理学视角可以追溯到霍伊特(Hoyt)的扇形模型,提供了关于居民迁居和城市社会空间结构之关系的解释。过滤理论意义主要有:为低收入群体提供合适住房、解释城市微观和宏观空间变化、分析和解释与住房市场有关的社会问题。过滤理论是中国城市转型研究的新视角。     

简论曹操对乌桓的征讨及意义

乌桓和袁绍势力的联合是导致曹操征讨乌桓的主要原因之一。在如何对待乌桓的问题上,曹操势力内部意见最初并不统一,但曹操最终采纳了郭嘉的建议,决定出兵乌桓。曹操北征乌桓的胜利,不仅将北疆分立的各政权纳入自己的管辖之下,实现了对北部地区的统一,而且为整军南下,专力于对付割据江东的孙权,以及亡命南方的刘备等解除了后顾之忧,但更重要的是中断了乌桓实现民族统一的历史进程,为乌桓人最终融合于汉等其他民族提供了前提。     

A note on physical properties of musket fire

While the use of ballistics data and principles to clarify historical experience of firearms is to be encouraged, their application is not always straightforward. This paper emphasizes the need for care. An example is given of too sanguine reliance on period studies, specifically of muzzle velocity, and of inadequate appreciation of the physics, in particular of the Magnus force.     

The radiocarbon reservoir effect: new evidence from the cemeteries of the middle and lower Dnieper basin,Ukraine

This paper presents preliminary results of new radiocarbon dating of human, faunal and fish skeletal remains from a number of the cemeteries from the Middle and Lower Dnieper Basin, Ukraine. The results appear to demonstrate the presence of a radiocarbon reservoir effect during the Neolithic–Eneolithic periods, the first time that this has been identified in this region. The data indicate that the radiocarbon reservoir effect is currently only evident during these periods, and not in the earlier Epipalaeolithic–Mesolithic periods, prompting the suggestion that the radiocarbon reservoir effect is associated with elevated fish consumption from the Neolithic period onwards.     

Coast–inland mobility and diet in the Danish Mesolithic and Neolithic: evidence from stable isotope values of humans and dogs

Here we present the stable isotope ratios of carbon and nitrogen measured in bone collagen extracted from humans, dogs, herbivores and fish from Mesolithic and Neolithic coastal and inland sites in Denmark. Bones of freshwater fish from several Early Mesolithic lake-side sites have δ¹³C values surprisingly similar to those seen in marine fish. We propose a model, based on δ¹³C and δ¹⁵N, for the correction for both marine and hard water reservoir effect in radiocarbon dates. A strong reliance on aquatic protein is demonstrated for the Mesolithic inhabitants of the region from the middle of the Early Mesolithic onwards. A significant part of the protein in the diets of the dogs and humans from the Middle and Late Mesolithic was of marine origin, even at inland sites. This observation points to a high degree of (seasonal) coast-inland mobility. The isotopic evidence indicates that during the Neolithic small quantities of aquatic foods were still common sources of dietary protein.