Two-level national-regional planning and mathematical programming decomposition applied to spatial price equilibrium models2

This paper is concerned with computation strategies related with the quantitative analysis of only a sector of a global economy (e.g. agriculture or energy). Under a ceteris paribus condition on the environment of the sector, and within the hypothetical context of the neoclassical economic theory, it is well known a type of partial equilibrium model that can be cast mathematically into an optimization framework. We attempt here to a typical specification which considers spatially separated markets, that has been called spatial price equilibrium model and that has contained within it many classical transportation problems (one for each commodity). The model is specially suitable for mathematical programming decomposition, resulting regional sybsystems whose coupling variables are the transportation flows. We explore here this structure, discussing two decomposition algorithms with economic interpretations that suggest decentralized procedures for planning. The first—of the price coordination type—is a variant of the Dantzig-Wolfe's principle which is expected to have a low number of cycles of information flow between the master level and the sub-problems (at each cycle it is calculated a series of regional production-consumption responses to alternative prices generated by transhipment problems at the central planning level). The second algorithm specializes the Geoffrion's projection/feasible directions technique, so interpreting the problem solution within the context of a net-output target coordination.     

应用田口方法的利与弊

本文分析了田口方法的优缺点,使应用田口方法的科研人员对它有正确认识,以便更好地在石油行业推广应用它。     

Farewell Anatolia: Refugees & the rise of the Greek Left

The population exchange of 1923 between Greece and Turkey consolidated the influx of more than 1.5 million refugees from Anatolia and East Thrace into Greece. In this article, we exploit the regional distribution of refugees at the sub-prefectural (province) level as a natural experiment in order to delineate the political effects of what the Greeks call the Asia Minor Catastrophe. We find that the settlement of refugees produced positive persistent effects on the electoral share of left-wing parties in the interwar and postwar periods. This is particularly the case for provinces with a high settlement rate of refugees originating from Asia Minor rather than from East Thrace or the Black Sea region. However, the refugee impact on the left-wing vote disappears completely in the post-dictatorship period.     

Clash of civilizations demystified

This paper provides empirical evidence in support of the clash-of-civilizations view on the nature of interstate conflicts in the post-Cold War era. First, we show that countries belonging to different civilizations have a higher probability of interstate conflict before and after the Cold War period, but not during the Cold War. Second, we explain the differential impact of civilizations on conflict over time by providing evidence that civilizational differences were suppressed during the Cold War by ideology and super-power camps. Third, we provide evidence that the component of civilizations that matters the most for conflict in the post-Cold War period is language, and not religion. Fourth, we analyze the long-term cultural, geographical and historical determinants of civilizational differences, and show that language has the largest explanatory power.     

Are China's Exports Crowding Out or Being Crowded Out? Evidence from Japan's Imports

Previous studies have investigated whether Chinese exports have crowded out those from other countries. However, what has yet to be considered is the evidence based on different quality varieties. Using the most detailed Harmonized System 9‐digit product‐level data, the present paper provides evidence of crowding‐out and crowded‐out effects across different product quality segments and across manufacturing sectors by quality segments. The empirical evidence presented in this paper shows that the crowding‐out effects of Chinese exports have been greatest at the lower end of the quality spectrum but less significant at the higher quality spectrum. Moreover, since 2007, China's own exports of lower quality manufactured goods have been increasingly crowded out. The key policy implication is that China's export path is in line with that taken by other Asian economies in previous decades; the crowded‐out effect could achieve win–win outcomes for countries involved; and lower income countries would do well to be open to receive those relocated low value‐added industries from China. However, the relocation policy in China is best implemented gradually as climbing up the product quality ladder takes time.     

定量检测SARS-CoV N蛋白的悬浮芯片方法研究

利用悬浮芯片技术,建立定量检测SARS-CoV N蛋白的悬浮芯片方法。用抗体包被编码微球作为反应载体,双抗体夹心法为反应模式,建立了SARS冠状病毒悬浮芯片检测方法,通过盲样和实验室标准检测等评估,表明适用于现场样品的检测。检测SARS冠状病毒N蛋白的灵敏度为4.86 ng/mL,在4.86-25600 ng/mL浓度范围内具有良好的动力学响应特性,比ELISA方法有较高的灵敏度和较宽动态检测范围。在早期识别、快速诊断和应对生物恐怖威胁、传染病暴发中具有广阔的应用前景。     

Gunboats, reputation, and sovereign repayment: lessons from the Southern Confederacy

Many states that formed the Southern Confederacy defaulted on sovereign debt sold in international capital markets during the 1840s. The Confederacy also elected President Jefferson Davis, who openly advocated the repudiation of U.S. states' debts while a member of Congress. Despite its poor credit record, the Confederate government managed to float cotton bonds in England that constituted under 2% of its expenditures. The bonds were largely issued to settle overdue debts with gun contractors who had cut off trade credit. The South serviced the bonds as late as March 1865, a time of domestic hyperinflation and weeks before the fall of Richmond. Although the Confederate experience shows that trade sanctions can promote debt repayment, the gunboat model can only account for a small amount of lending. A reputation or another type of sanction would be necessary to support higher levels of lending in international capital markets.     

氮肥减量及秸秆替代过量氮肥下冬小麦/夏玉米轮作体系氮素淋失风险研究

针对过量施用氮肥和地下水硝酸盐超标的现状,探索减量施氮、秸秆替代过量氮肥下土壤氮素的淋失风险,以期为降低氮素淋失风险提供科学依据。通过在河北省徐水县进行连续4年的冬小麦—夏玉米轮作体系田间定位试验,分析耕作(少耕和常规耕作)、施氮量(无机氮0、200和300 kg/hm~2)和秸秆(还田、不还田)等措施对作物收获后土壤无机氮累积、土壤—作物体系氮平衡状况以及冬小麦和夏玉米产量的影响。结果表明,小麦收获后,过量施氮处理0~100 cm土壤硝态氮累积量显著高于其它处理,高达221 kg/hm~2,过高的土壤残留硝态氮增加玉米高温多雨季氮素淋洗风险。3年氮平衡累积量比较显示,过量施氮、少耕/常规耕作减量施氮秸秆还田3处理的氮平衡值无显著性差异,以少耕减量施氮秸秆还田最低,为236 kg/hm~2,过量施氮处理最高,为281 kg/hm~2,三者均显著高于少耕/常规耕作减量施氮秸秆不还田处理。冬小麦—夏玉米轮作体系氮平衡值与0~100 cm土层的土壤无机氮、土壤硝态氮累积量呈显著正相关,说明氮素大量盈余会导致0~100 cm土壤剖面无机氮大量累积,尤其是硝态氮大量累积。少耕和常规耕作减量施氮秸秆还田处理的冬小麦、夏玉米产量与过量施氮无显著差异。综合考虑土壤无机氮累积量、氮平衡值和作物产量,少耕或者常规耕作下,可以利用秸秆氮替代过量无机氮,降低氮素淋洗风险。     

Taking technology to task: The skill content of technological change in early twentieth century United States

This paper uses new data on the task content of occupations to present a new picture of the labor market effects of technological change in pre-WWII United States. I show that, similar to the recent computerization episode, the electrification of the manufacturing sector led to a “hollowing out” of the skill distribution whereby workers in the middle of the distribution lost out to those at the extremes. OLS estimates show that electrification increased the demand for clerical, numerical, planning and people skills relative to manual skills while simultaneously reducing relative demand for the dexterity-intensive jobs which comprised the middle of the skill distribution. Thus, early twentieth century technological change was unskill-biased for blue collar tasks but skill-biased on aggregate. These results are in line with the downward trend in wage differentials within U.S. manufacturing up to 1950.     

Did the New Deal solidify the 1932 Democratic realignment?

The critical election of 1932 represented a turning point in the future electoral successes of the Democrats and Republicans for over three decades. This paper seeks to measure the importance of the New Deal in facilitating the Democrats' control of the federal government well into the 1960s. We test whether long-differences in the county-level electoral support for Democratic presidential candidates after the 1930s can be attributed to New Deal interventions into local economies. We also investigate more narrowly whether voters rewarded Roosevelt from 1932 to 1936 and from 1936 to 1940 for his efforts to stimulate depressed local economies. Our instrumental variable estimates indicate that increasing a county's per capita New Deal relief and public works spending from nothing to the sample mean ($145) would have increased the long-run support for the Democratic party by 2 to 2.5 percentage points. We further find that the long-run shift toward the Democratic party after 1928 was not a function of the Roosevelt landslide victory in 1932. Roosevelt's ability to win over voters during the 1936 and 1940 elections with New Deal spending, however, did matter for the long-term.