Mode Choice in a Hub-and-Spoke Network: A Zero-One Linear Programming Approach

While research has tackled the hub-and-spoke network design problem, that research has overlooked the air-truck modal integration issue which is a common feature of real express delivery systems. This paper devises integer linear programs to represent the mode and route assignment aspects of the operational problem. The model is solved under four different levels of delivery schedule, and the results show that as the promised delivery schedule is relaxed, not only does the use of truck routes become more desirable, but also interesting adjustments in mode and hub assignment occur. Consider the case of hubs in Los Angeles and Dayton. As the time constraints are relaxed, cities such as Minneapolis and New Orleans originally linked by air to Los Angeles, switch to Dayton because cheaper truck routes become feasible.     

"承上制下"与"从左转右":北宋物资转输区域的互动——以东南地区为中心

北宋时期,朝廷在淮南地区运河沿岸州军设置转般仓,这些州军具有了转般粮食物资进京的功能;又先后置发运司于真州和泗州,使其开始具有总管东南漕运事务的职能;盐利也集中于此,同时亦掌控着地方物资的上供经费.其他物资转输区域则经常出现改变转运方式的情形,中转区域改变了起始区域输出物资的运输方式,减轻了部分运输成本.起始区域在加重中转区域负担的同时,亦对中转区域的经济繁荣有促进作用.     

在朝或居乡:元末明初师儒汪叡的出处选择

元明易代之际儒者的出处选择,不仅取决于个体的心性特质,更是当事人的身份背景和行事经历的反映.晚明史籍常将婺源汪叡视为明代开国时期重要的循良师儒,但却忽略了他对于洪武朝廷所秉持的疏离态度.元末动乱使汪叡有机会从默默无闻的乡儒崛起为绥靖地方的精英,但这一经历在明初却同样给他带来了无法避免的政治困境,以至于汪叡虽然曾短暂入仕,却始终难以充分建立对新朝的政治认同.     

Micro-CT-assisted determination of the shattering and non-shattering phenotypes of charred rice spikelet bases from archaeological sites: a new methodological approach

The selection of a non-shattering phenotype is a pivotal change in the process of rice domestication. However, current research is heavily restricted by the preservation conditions of macro-plant remains in early and middle Neolithic sites, as very limited well-preserved rice spikelet bases could be retrieved. We present a non-destructive method based on micro-computed tomographic (CT) scanning, which could provide detailed visualization of the internal structures of charred spikelet bases and efficiently discriminate the shattering and non-shattering phenotypes of rice spikelet bases according to the abundance of fusiform echinate phytoliths. It could be widely applied in different contexts, especially those poorly preserved specimens and tempers in pottery sherds, greatly improving our knowledge of rice domestication.     

Study on the strontium isotope standard in pig teeth excavated from Zaoshugounao site,Shaanxi Province of China

In archaeology, strontium isotope analysis is developing into an efficient scientific technique for tracing the movement of prehistoric humans and animals. Determining the local bioavailable ⁸⁷Sr/⁸⁶Sr ratio range is the key to distinguishing whether the human or animal is indigenous to the local area. It has been shown that the ⁸⁷Sr/⁸⁶Sr ratio in the enamel of pigs can be an excellent sample to determine the range of local strontium isotope ratio at the site. However, pigs may not be all local at the site, and there is no special study on whether pigs’ different ages and tooth types impact the local strontium isotope characteristics. In this paper, the tooth enamel of 19 pigs from the Zaoshugounao site for strontium isotope ratio (⁸⁷Sr/⁸⁶Sr) by multicollector–inductively coupled plasma mass spectrometry. There were no significant differences in ⁸⁷Sr/⁸⁶Sr ratios of local pigs at different months and different molar types, which did not affect the determination of the local strontium isotope standard. Based on the local strontium isotope ratio range (0.711056–0.711476), we found that five pigs were non-local. The Jing and Wei river basins (in Guanzhong basin) and northern Shaanxi are likely sources of non-pigs.     

AN ARTISTIC LIFE CREATED BY A PAIR OF SKILLFUL HANDS

正The cold season isjust about to arrive in Lhasa.A tallllbetan man is standing upon the golden roof of the Jokhang Temple to look out into distance.His name is Tsegya,a man with a deep affection for this very roof.This is the place where his karma connects him to his produced mandalas.Tsegya told me that     

俄罗斯外国劳务移民与中国移民研究

论文利用俄罗斯联邦移民局和联邦统计局的数据,采用统计分析法,探讨近年来俄罗斯移民尤其是劳务移民的数量、结构、地区分布、从事行业以及中国移民在俄罗斯的发展状况,指出了俄罗斯在制定移民政策存在的弊端,并从"现有移民政策的局限"和"有效管理外国劳务移民"等方面提出了对策建议。认为一国移民政策的制定和调整应符合该国经济和人口发展的大局,而且要认识到移民是在经济全球化大背景下,促进区域经济一体化的重要力量。     

抗战中的知识分子

作者通过对甲午战争至全面抗战爆发历史的回顾,分析期间中国知识分子的思想变化.并分析抗战爆发后知识分子通过不同的方式积极投入救亡运动,重新认识抗战期间的知识分子的真实处境和历史,提出应更理性、客观的去看待抗战时期的知识分子的选择,无论是自由主义知识分子、马克思主义知识分子还是新儒家知识分子,对近代中国文化的追求,根本上都是“三民主义”.     

元代徽州路的军功家族

文章利用《汪氏渊源录》和《回岭汪氏宗谱》以及相关元代文集为主要参考资料,研究了元代徽州路的军功家族群体,尤其是其中的典型个案———婺源回岭汪氏。作者认为婺源回岭汪元龙、汪元圭兄弟在宋元易代之际,因为归附蒙元及“保障乡里”之功走上致身荣显的仕宦之路,他们不仅自身建立了可观的权势,而且有效地将之世代传承,以与元朝统治相始终,最终使婺源回岭汪氏家族成为“朱紫满庭”的“新安巨室”。在元代的徽州,类似的军功家族分布广泛,人数众多,深具影响。他们的出现,与元代统治者重视“根脚”的政治铨选原则紧密相关,与那些在蒙元征服战争中出现的“汉军世家”具有相似的来源和特点。