OLIGOPOLISTIC COMPETITION AND ECONOMIC GEOGRAPHY*

ABSTRACT This paper studies a general equilibrium model of economic geography in which firms engage in oligopolistic competition. This framework is conducive to analytic results. With increasing returns, oligopolistic competition leads to interindustry trade between regions rather than intraindustry trade. The choice of appropriate technology is a channel of concentration of industries.     

Stories behind the fortress: Stable isotope analysis and 14C dating of soldiers' remains from the Bayanbulag site,Mongolia

Stable carbon and nitrogen isotope analysis of 15 individuals buried closed to Bayanbulag site or the Shouxiangcheng fortress in southern Mongolia revealed complex dietary features. Only one individual had a diet similar to that of the pastoral population in northern China, while the others, who had varying carbon isotope values and low nitrogen values, might have been from different agricultural areas. ¹⁴C dating results suggest that the earliest interment could be much earlier than the building of Shouxiangcheng fortress recorded in Han texts. Analysis of the burial arrangement further confirmed that these deceased were not buried at the same time.     

Development at the Edge of Difference: Rethinking Capital and Market Relations from Lugu Lake,Southwest China

This paper rethinks the relationships between capitalist development in indigenous places and the fabric of local differences and specificities. It first develops a critical appraisal of the celebration of ethnic identities, local agency and indigenous knowledge in existing literatures. It suggests that, based on such insights, we can further envision the possibility of questioning and problematising the ontology and concept of the capitalist economy. Above all, this paper is interested in non-capitalist factors percolating into capitalist economies and creating fissures in their logical and ontological coherence. It examines how capitalist economies depend on local specificities to achieve particular configurations. We elucidate this argument with a case study of indigenous development in Lugu Lake, Southwest China, which is inhabited by the ethnic Mosuo people. Through the dual lenses of land and labour, we pay special attention to the transition from grassroots development initiatives to heavy dependence on exogenous capital and entrepreneurs.     

敦煌、吐鲁番文书所见“舍”之记载差异及其用途探微

敦煌文书与吐鲁番文书对于“舍”的记载内容存在很大差异,仅就敦煌文书而言,其在不同时期对于“舍”的记载格式也有所不同。敦煌文书与吐鲁番文书记载内容的差异,反映了两地居民在各自特殊地理条件下的居住形态及田地经营方式的不同;而敦煌文书记载格式的变化,则反映出不同政权统治下敦煌地区均田制实施情况的差别。此外,敦煌、吐鲁番文书中的“舍”具有不同的用途,明确这一区别,有助于更加深入地理解中古时期两地居民的社会生活状况。     

春归秣陵树,人老建康城——读《南京传》有感

幼时对南京最大的印象,就是爸爸口中经常提到的南京长江大桥,这个宏伟的工程,在那一代人心中激起了太多的涟漪。就像外地人到北京一定要去天安门看一看,照张相一样,外地人来南京,也一定要南京长江大桥看一看,光是在来时的火车上看江面上往来的船只还不够,一定要坐上一辆从大桥上经过的公交车,从桥的这头一路坐到那头,然后下车,再一路坐回来才行。后来到了南京读书、工作,住在了老城南,呆得久了,才知道原来南京不只有中山陵、明孝陵、玄武湖、紫金山、夫子庙,还有太多历史的痕迹点缀其中,光是历代的名称就能把人绕晕,估计很多南京人自己也理不清楚,而却终归停留在不知道,也从未去深入探知它们背后的故事。     

魏晋十六国北朝关中侨置武都郡研究

前秦时关中氐人分布的武都是指侨置武都郡。侨置武都郡始于曹魏。曹魏为与蜀汉争夺陇右,将武都氐人迁徙至关中,并先后在小槐里和美阳设置武都郡以进行管理。西晋江统的《徙戎论》反映出此时关中武都氐聚居的地方未置武都郡。十六国初期屠各刘氏和羯族石氏先后统治关中,将大量氐羌迁往关东,因此这一时期在关中侨置武都郡缺乏现实基础。苻健立国关中后,在战略要地宝鸡附近侨置武都郡,是其氐人本位政策的体现。北魏时侨置武都郡始领县级行政单位,统治范围扩大,标志着氐人的关中化,同时它也是太武帝平定盖吴叛乱时分化关中南道氐人的重要战略举措。西魏北周立国关中后受政区滥置影响,武都郡领县减少。隋开皇间侨置武都郡在当权者废郡、保留州县的地方行政政策的影响下消失于历史舞台。     

Real-Time Dynamic Hybrid Testing Coupling Finite Element and Shaking Table

In this article, a Simulink simulation block with the finite element function is developed on the basis of S-function and implemented as the numerical substructure of real-time dynamic hybrid testing. Thereby, a real-time dynamic hybrid testing system coupling finite element calculation and shaking table testing is achieved. Using the developed system, a shear frame mounted on the soil foundation is tested, in which the shear frame is simulated as the physical model and the foundation is simulated as the finite element model with 132 degrees of freedom. Several cases of the dynamic behavior of soil-structure interaction are studied.     

Fluid effect on hydraulic fracture propagation behavior: a comparison between water and supercritical CO2‐like fluid

The initiation of hydraulic fractures during fluid injection in deep formations can be either engineered or induced unintentionally. Upon injection of CO₂, the pore fluids in deep formations can be changed from oil/saline water to CO₂ or CO₂ dominated. The type of fluid is important not only because the fluid must fracture the rock, but also because rocks saturated with different pore fluids behave differently. We investigated the influence of fluid properties on fracture propagation behavior by using the cohesive zone model in conjunction with a poroelasticity model. Simulation results indicate that the pore pressure fields are very different for different pore fluids even when the initial field conditions and injection schemes (rate and time) are kept the same. Low viscosity fluids with properties of supercritical CO₂ will create relatively thin and much shorter fractures in comparison with fluids exhibiting properties of water under similar injection schemes. Two significant times are recognized during fracture propagation: the time at which a crack ceases opening and the later time point at which a crack ceases propagating. These times are very different for different fluids. Both fluid compressibility and viscosity influence fracture propagation, with viscosity being the more important property. Viscosity can greatly affect hydraulic conductivity and the leak‐off coefficient. This analysis assumes the in‐situ pore fluid and injected fluid are the same and the pore space is 100% saturated by that fluid at the beginning of the simulation.     

Discrimination Against Floating Migrants in China:Take Rural-to-Urban Migrants in Beijing As An Example

This essay firstly examines the destiny of rural-to-urban migrants in Beijing, the capital of China. Relying on data collected from representative survey, the essay then provides the demographic profil...