Locating Vehicle Inspection Stations to Protect a Transportation Network

We develop a new conceptual approach to locating inspection stations for hazardous vehicles, prevention, and compare it to the previous, punitive, philosophy of the flow-capturing location model. We implement this preventive protection philosophy with a new mixed integer program that maximizes hazard avoidance by locating a number of inspection stations to detect and remove hazardous vehicles as early in their trips as possible. We test the model's performance and analyze the spatial characteristics of solutions simulating several potential applications. Our computations demonstrate that a relaxed integer-linear program is overly demanding computationally and that a simple greedy heuristic lacks robustness. We suggest further approaches to developing more powerful and efficient solution methods.     

The impacts of parental migration on children’s subjective well-being in rural china: a double-edged sword

ABSTRACT

The emerging problem of left-behind children has attracted mounting academic and policy attention. Prior studies primarily cast light on left-behind children’s education, health, and behavior, while their subjective well-being is much less understood yet. Based on a nationally representative sample of rural children aged 10–15 in 2014, we examine the impacts of different types of parental migration on children’s subjective well-being and how these affects vary between boys and girls. The results show that parental migration is a double-edged sword: children from both-parent migrant families report compromised life satisfaction and relationship quality compared with those in integral families, and mother-only migration significantly lowers children’s subjective health. On the flip side, father-only migration enhances children’s aspiration for attaining college, an encouraging effect that is even stronger than that of parental education and family income. These effects are heterogeneous by children’s gender: boys seem to be more susceptible to the disruptive effects of both-parent migration; mother-only migration effectively promotes girls’ educational aspiration while father-only migration promotes boys’. This study portrays a comprehensive image of left-behind children. Relaxation of hukou restriction, equal access to education, and revitalization of rural economies are imperative to improve the well-being of left-behind children.

Abbreviations: LBC: Left-behing children; SWB: subjective well-being     

WELL-FORGED "WALKING GOLD"——THE SHEEP BREEDING INDUSTRY IN THE GAMPA COUNTY

正It is just the dawn,but the sheepfolds have already begun to move restlessly.Sunlight makes its way in.Tashi Tsedan and Redan open the sheepfolds one after another.Flocks of sheep suddenly gush out like an influx of water from an opened gate.These two herdsmen from Jirong Village in Drik Town of Gampa County are fulfilling their duty grazing these flocks of Gampa sheep,a well-known breed of Tibetan sheep.     

关于美国民主的清教渊源

本文利用新英格兰殖民地的一些原始档案,通过考察新英格兰清教政体创立和运作的宗教理念以及立法、实践诸情况,论证新英格兰清教蕴含现代美国民主的某些理念和形式,具体体现为限权政府思想和地方教会自治原则,并且清教徒在现实生活中也在一定程度上享受某些“民主”权利。不过,这些“民主”倾向尚未完全跳出欧洲宗教改革运动的藩篱,在新英格兰殖民地创立初期尤为如此,因此,有很大的时代局限性,不可与现代美国民主观念相互混谈,更不可等同。虽然如此,随着时代的推移和新英格兰殖民地现实生活的演进,清教不可避免地日益世俗化,最终成为现代美国民主的来源之一。     

对编纂资料性国史书的几点思考——以《中华人民共和国日史》为例

中共十一届三中全会以来,随着中华人民共和国史研究的广泛开展,一批体例各异、详略不一的资料性国史书相继出版。四川人民出版社2003年8月推出的卷帙浩繁的《中华人民共和国日史》(以下简称《日史》),就是其中之一。该书以年分卷,逐日记事,上自1949年10月1日起,下至1999年12月31日止,共计50卷。编纂者称该书是国家断代性质历史,     

张尔田与《清史稿》纂修

1914年袁世凯政府批准国务院关于设馆纂修清史的呈文,设立清史馆。清史馆历经14年编纂,于1927年刊印《清史稿》行世。由于编纂的政治态度和仓促付印等先天的不足,《清史稿》自行世之后,一直受人诟病,并曾一度被国民政府封禁。但是《清史稿》对相关历史资料进行了汇集和排比,所据史料丰富,是研治清史的基本参考书,对其深入研究仍属必要。而且《清史稿》的纂修人员虽然立场保守,但其中并不乏严肃认真的史家,其撰著理念和方法,亦值得总结。目前国家正     

邓小平政治合法性思想探微

十一届三中全会以后,邓小平以其睿智和远见,从重塑主流意识形态、加强经济绩效建设、启动政治权威的法理化转型、加强执政党的建设等四个方面,着力构建新时期党的执政合法性基础。在邓小平政治合法性思想的指导下,我们党不仅成功地化解了“文革”导致的政治合法性危机,而且经受住了20世纪80年代末和90年代初国内外政治风波的考验,避免了前苏联及东欧一些国家政权变色和国家分裂的悲剧。邓小平的政治合法性思想,对新世纪保持我们党执政地位的稳固和国家的长治久安,有着长远的指导意义。     

佛光寺东大殿实测数据解读

结合山西省古建筑保护研究所2004年、清华大学2005—2006年对五台山佛光寺东大殿的手工测绘和三维激光扫描测量,本文借鉴前辈学者对于佛光寺东大殿原始设计尺寸权衡的论述,在今天毫米级精度的测量数据的基础上,得出以下结论:东大殿所用营造尺长298毫米,中五间开间1丈7尺,标准柱高同之;斗拱材宽7寸;斗拱下昂斜度等于总举斜度,基本斜度可描述成“平出47分~(?),抬高21分~(?)”,总举为此基本斜度的11倍,稍间、进深各间尺寸因此定为1丈4尺8寸;中平槫到柱头的高度等于总举高。通过上述的分析与结论,本文强调提高古建筑测绘数据全面性和精度的重要意义及深远的科研前景。     

清雍正朝的官造玻璃器

玻璃器是清代工艺美术品中的新宠,备受皇家珍爱。清代的玻璃制造始于康熙朝。雍正朝在此基础上继续投入大量的人力、物力制作为皇室享用、馈赠的玻璃器皿。本文通过对中国第一历史档案馆收藏的《造办处各作成做活计清档》中有关雍正朝玻璃制作档案的整理,并结合现存珍贵的玻璃实物,系统地对雍正朝玻璃厂制作的玻璃品种、工艺、用途及风格特点进行了论述。     

历史时期疏勒河水系变迁及相关问题研究

疏勒河是河西走廊西部的重要河流,关于历史时期其水系的演变问题,前辈学者已从不同角度予以关注,但在方法与详尽程度方面仍有较大改进空间。本文在充分发掘地方文献的基础上,充分利用游记、考古材料,并结合自然科学相关研究成果,就历史时期各阶段疏勒河流域水系分布状况与演变过程进行了全面讨论,订正了一些广为流传的明显错误,并就其中涉及到的部分古代地名问题提出了自己的看法。