“强化谎者”悖论的简明消解——批判塔斯基、哥德尔、爱因斯坦的相关“论点”

讨论了“仅是矛盾”和“矛盾被证”、辩证“鹰”派的反驳和逻辑派的回应、几个悖论的消解等，评述了维特根斯坦和哈克的“自涉”、克林的“悲观”情怀，批评了爱因斯坦的“轻率概括”，突显出谬误学、批判性思维的重要性。     

Unit Root Hypothesis in the Presence of Stochastic Volatility, a Bayesian Analysis

This paper investigates the impact of stochastic volatility on the Dickey–Fuller unit root test. Monte Carlo simulations show that the test size is seriously distorted if nonstationary stochastic volatility is ignored. To improve the performance of the test, we propose a Bayesian test for unit root that is robust in the presence of stationary and nonstationary stochastic volatility. The finite sample property of the proposed test statistic is evaluated using Monte Carlo studies. Applying the developed method, we test the policy effect of the Split Share Structure Reform, which is an important milestone for the development of the emerging stock market in China.     

HEDC＋＋： An Extended Histogram Estimator for Data in the Cloud

With increasing popularity of cloud-based data management, improving the performance of queries in the cloud is an urgent issue to solve. Summary of data distribution and statistical information has been commonly used in traditional databases to support query optimization, and histograms are of particular interest. Naturally, histograms could be used to support query optimization and efficient utilization of computing resources in the cloud. Histograms could provide helpful reference information for generating optimal query plans, and generate basic statistics useful for guaranteeing the load balance of query processing in the cloud. Since it is too expensive to construct an exact histogram on massive data, building an approximate histogram is a more feasible solution. This problem, however, is challenging to solve in the cloud environment because of the special data organization and processing mode in the cloud. In this paper, we present HEDC＋＋, an extended histogram estimator for data in the cloud, which provides efficient approximation approaches for both equi-width and equi-depth histograms. We design the histogram estimate workflow based on an extended MapReduce framework, and propose novel sampling mechanisms to leverage the sampling efficiency and estimate accuracy. We experimentally validate our techniques on Hadoop and the results demonstrate that HEDC＋＋ can provide promising histogram estimate for massive data in the cloud.     

Sequential entry and merger in spatial price discrimination

This paper newly introduces sequential entry into previous models of spatial price discrimination that examine location choices made in anticipation of a potential merger. While merger with simultaneous entry routinely reduces social welfare, we show that mergers frequently improve welfare. The extent of welfare improving mergers varies inversely with the timing advantage of an excluded rival. When the rival locates alone in the first stage, the merger harms welfare. When the rival locates alone in the last stage, the merger improves welfare. These results hold true when allocating three firms across either two or three location stages. Thus, allowing staged entry dramatically alters and often reverses the conclusion previously drawn on the basis of simultaneous entry.     

有机食品博览会的评估分析及对策建议

本文基于对第三届中国国际有机食品博览会——BioFach China 2009参展商和观众的调查,从展会组织、宣传、展览视觉效果和服务几个方面分析了参展商和观众对BioFach China 2009的评估情况。提出的发展对策为加大宣传力度、做好展商观众组织、重视展览视觉效果和提高服务水平。     

Household electricity demand in Latin America and the Caribbean: A meta-analysis of price elasticity

Studying the price elasticity of demand is essential when considering rate policies in the electricity sector. This research aims to perform a meta-analysis and a meta-regression of the price elasticity of electricity demand for the residential sector in Latin American and Caribbean countries. Results show that the true value of the short-term price elasticity is between −0.197 and −0.468 and, for the long-term, is between −0.252 and −0.331. Findings differ substantially when studies are classified by their quality in econometric procedures. The long-term price elasticity seems to be lower than estimates found for other regions.     

SBSE-TDU-GC快速测定茶叶中7种拟除虫菊酯类农药残留

采用搅拌棒吸附萃取技术(SBSE)对茶叶中7种拟除虫菊酯类农药残留进行一次性吸附萃取,使农药与其他杂质得到较好分离,再用热脱附-气相色谱仪器(TDU-GC)分析.所使用的SBSE-TDU-GC方法可以同时定性、定量测定7种拟除虫菊酯类农药残留,在给定的质量浓度范围内,各农药组分呈现良好的线性相关,7种拟除虫菊酯类农药的平均回收率为97.06%～104.48%,相关系数大于0.9937,变异系数小于9.5%.用该方法测定4种茶叶中的拟除虫菊酯类农药残留,其残留最均低于我国和欧盟的MRL.     

Application of MBR for hospital wastewater treatment in China

In China, the number of hospitals has increased to 19,712 in 2008, with the production of hospital wastewater reaching 1.29 × 10⁶ m³/d. Membrane bioreactor (MBR) technology presents a more efficient system at removing pathological microorganism compared with existing wastewater treatment systems. In the past 8 yr, over 50 MBR plants have been successfully built for hospital wastewater treatments, with the capacity ranging from 20 to 2000 m³/d. MBR can effectively save disinfectant consumption (chlorine addition can decrease to 1.0 mg/L), shorten the reaction time (approximately 1.5 min, 2.5-5% of conventional wastewater treatment process), and attain a good effect of inactivation of microorganism. Higher disinfection efficacy is achieved in MBR effluents at lower dose of disinfectant with less disinfection by-products (DBPs). Moreover, when capacity of MBR plants increases from 20 to 1000 m³/d, their operating cost decreases sharply.     

Graphene as a conductive additive to enhance the high-rate capabilities of electrospun Li4Ti5O12 for lithium-ion batteries

Spinel Li₄Ti₅O₁₂ (LTO) is a promising candidate anode material for Li-ion batteries due to its well-known zero-strain merits. To improve the electronic properties of spinel LTO, which are intrinsically poor, we processed the material into a nanosized architecture to shorten the distance for Li-ion and electron transport using the versatile electrospinning method. Graphene was chosen as an effective carbon coating to improve the surface conductivity of the nanocomposites. The as-prepared graphene-embedded LTO anode material showed improved discharging/charging and cycling properties, particularly at high rates, such as 22 C, which makes the nanocomposite an attractive anode material for applications in electric vehicles.