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Chinese rare earth export policies currently result in accelerating its depletion. Thus adopting an optimal export trade selection strategy is crucial to determining and ultimately identifying the ideal trading partners. This paper introduces a multi-attribute decision-making methodology which is then used to select the optimal trading partner. In the method, an evaluation criteria system is established to assess the seven top trading partners based on three dimensions: political relationships, economic benefits and industrial security. Specifically, a simple additive weighing model derived from an additive utility function is utilized to calculate, rank and select alternatives. Results show that Japan would be the optimal trading partner for Chinese rare earths. The criteria evaluation method of trading partners for China's rare earth exports provides the Chinese government with a tool to enhance rare earth industrial policies. [ABSTRACT FROM AUTHOR]

Variation of streamflow and sediment load in the Yellow River basin has received considerable attention due to its drastic reduction during the past several decades. This paper presents a detailed investigation on the changes of streamflow and sediment load from 1952 to 2011 using monthly observations at four gauging stations along the Yellow River. The results show significant decreasing trends for both streamflow and sediment load at all four gauging stations over the past 60 years. The wavelet transform demonstrated discontinuous periodicities from 1969 to 1973 and after 1986 due to the construction of large reservoirs and implementation of numerous soil and water conservations practices. The sediment rating curves with the power-law function was applied to investigate the relationship between discharge and sediment load. The results indicate distinct variations of the relationship between streamflow and sediment and implied significant hydro-morphological changes within different periods. The reducing sediment supply from the source region and the increased erosive power of the river are detected at Lanzhou station, while the decrease of the transport capacity at Toudaoguai is caused by severe siltation. Significant changes in the relationship between streamflow and sediment load are found at Huayuankou and Gaocun stations, which are largely induced by evident sediment income and trapping effects of large reservoirs. It is estimated that numerous reservoirs have strongly altered the regime and magnitude of streamflow and trapped large amount of sediment, leading to severe siltation and evident reduction of their total volumes. A decrease in precipitation, incoming water from the upper reaches, soil and water conservation measures as well as water consumption contribute most to the significant reduction of streamflow. The decrease of sediment load mainly resulted from various soil and water conservation measures and trapping in reservoirs from 1986 to 2011. [ABSTRACT FROM AUTHOR]

Several approaches have been proposed for near real-time detection and prediction of the spread of influenza. These include search query data for influenza-related terms, which has been explored as a tool for augmenting traditional surveillance methods. In this paper, we present a method that uses Internet search query data from Baidu to model and monitor influenza activity in China. The objectives of the study are to present a comprehensive technique for: (i) keyword selection, (ii) keyword filtering, (iii) index composition and (iv) modeling and detection of influenza activity in China. Sequential time-series for the selected composite keyword index is significantly correlated with Chinese influenza case data. In addition, one-month ahead prediction of influenza cases for the first eight months of 2012 has a mean absolute percent error less than 11%. To our knowledge, this is the first study on the use of search query data from Baidu in conjunction with this approach for estimation of influenza activity in China. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes changes which took place in 37 Hong Kong primary schools where class sizes were reduced from 38 to between 20 and 25. Chinese, English and mathematics classes were observed over three years from Primary 1 (aged 6) to Primary 3. For 75% of observations no child was the focus of the teacher''s attention in large classes. Reducing the class size did not change this situation appreciably, although teachers claimed that smaller classes increased the amount of individual attention that pupils received. For some teachers cluster analysis did identify shifts in teaching methods away from whole class instruction and the implications of this finding for when Hong Kong ‘goes to scale’ across the primary phase are discussed. [Copyright &y& Elsevier]

The structural behavior of T-frame bridges is particularly complicated and it is difficult using a general analytical method to directly acquire the internal forces in the structure. This paper presents a spatial grillage model for analysis of such bridges. The proposed model is validated by comparison with results obtained from field testing. It is shown that analysis of T-frame bridges may be conveniently performed using the spatial grillage model. [ABSTRACT FROM AUTHOR]

Abstract: The algorithms used in Arabic and medieval European mathematics for extracting cube roots are studied with respect to algebraic structure and use of external memory (dust board, table, paper). They can be separated into two distinct groups. One contains methods used in the eastern regions from the 11th century, closely connected to Chinese techniques, and very uniform in structure. The other group, showing much wider variation, contains early Indian methods and techniques developed in central and western parts of the Arabic areas and in Europe. This study supports hypotheses previously formulated by Luckey and Chemla on an early scientific connection between China and Persia. [Copyright &y& Elsevier]

Abstract: Tripterygium Glycosides (TG) is effective in the treatment of patients with a variety of inflammatory and autoimmune diseases, especially rheumatoid arthritis (RA) in clinical. Wilforlide A (T1) serves as a quality control standard of TG that be listed in Drug Standard of Ministry of Public Health of the People''s Republic of China. The pharmacologic actions of T1 remain to be unidentified. In this paper, we studied the anti-inflammatory and immune suppressive effect of T1, and compared it with Triptolide (TP), which believed to be the major active component of TG. Carrageenan-induced rat pedal swelling, tampon-induced rat granulation, and mice ear inhibition rate of swelling trail results show that high-dose T1 has obvious anti-inflammatory effect. Colorimetric detection contents of hemolysin, carbon elimination from plasma of mice, mice delayed hypersensitivity immune, and organ index were measured. The results show that T1 has no significant immune suppressive activity, and there has a significant difference with TP and TG. Therefore, we think the content of TP also should be controlled as a supplement standard in order to ensure safe and effective medication. [Copyright &y& Elsevier]

Abstract: The study of Hamiltonian systems is important for space physics and astrophysics. In this paper, we study local behavior of an isolated nilpotent critical point for polynomial Hamiltonian systems. We prove that there are exact three cases: a center, a cusp or a saddle. Then for quadratic and cubic Hamiltonian systems we obtain necessary and sufficient conditions for a nilpotent critical point to be a center, a cusp or a saddle. We also give phase portraits for these systems under some conditions of symmetry. [Copyright &y& Elsevier]

Jinsha River has very abundant hydro power reservation, ranking first in all the hydro power bases of China. To deliver the 38-GW hydro power from Jinsha power stations by HVDC transmission lines to load centers 1000-2000 km away, it is necessary to determine the right voltage level and the capacity of each bipole. This paper proposes three preliminary power delivery scheme and presents an optimization method for transmission capacity, dc voltage and conductor size. Based on a comprehensive comparison of cost-effectiveness, technical feasibility and network security and stability, it was recommended that the 3 bipolar ±800-kV ultra HVDC (UHVDC) links with rated capacity of 6.4 GW for each link be adopted as transmission scheme of Phase I Hydro Power station on Jinsha River. [ABSTRACT FROM AUTHOR]

There were numerous records of solar eclipse in China from the eighth century BC to the fifteenth century AD. Because these records are concise and formalized, I have arranged 938 items into a computer-readable table called ‘‘The table of historic Chinese regular records of solar eclipse’’. In this paper, I explain the structure of the table with a preliminary analysis and statistics of the historical records. To receive the table itself, please request it at liucy@ntsc.ac.cn. [ABSTRACT FROM AUTHOR]

Let G be a graph of size n, and let ƛ1 ƛ2; ƛ3, be its eigenvalues. The Estrada index of G is defined as EE(G) = Σn i=1 ƛi . In this paper, we establish almost sure results on EE(G(n; p)) of Erdös-Rényi random graph G(n; p) in the uperconnectivity regime. [ABSTRACT FROM AUTHOR]

The article presents a biography of Wei Lin. Wei Lin was born on September 7, 1934 in Chao Yong County, Guangdong province, China. He entered the Department of Mathematics at Zhongshan University in 1956. He became an associate professor at Zhongshan University in 1978. He visited the University of Delaware in 1982. He has also authored a number of books and papers related to mathematics.