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Liu Z.,Chinese Peoples Public Security University | Chen L.,Peking University | Li L.,Old Dominion University | Zhai X.,Peking University
International Journal of Production Economics | Year: 2014

In this research, two risk hedging strategies, the option contract and the advance purchase discount contract, are investigated within a manufacturer-retailer two-echelon supply chain context. This study offers three contributions. First, the optimal decisions under the two contracts from the perspectives of both the manufacturer and the retailer are determined. Second, circumstances under which supply chain coordination can be reached are identified. Third, the scenario of loss-averse manufacturer has been explored. The results of the analysis provide practical insights to the manufacturer when she plans production quantity and to the retailer when he replenishes inventory. © 2014 Elsevier B.V. Source

Wang R.,Chinese Peoples Public Security University
Proceedings - 2011 International Conference on Multimedia and Signal Processing, CMSP 2011 | Year: 2011

An edge detection method based on lifting wavelet and mathematical morphology is proposed in this paper. Firstly, the original image is decomposed by lifting wavelet transformation; secondly, the edge pixels in low-frequency subimage are detected by morphological gradient and edge pixels in high-frequency sub-images are detected by the largest value of the module of wavelet coefficients; the two edge images obtained respectively by the morphology and wavelet are fused according to some rules at last. The experimental results show that the performance obtained by the method proposed in this paper is better than the one obtained by either of morphology method and wavelet method. © 2011 IEEE. Source

Ma Z.,Changan University | Shao C.,Beijing Jiaotong University | Ma S.,Chinese Peoples Public Security University | Ye Z.,Beijing Transportation Research Center
Expert Systems with Applications | Year: 2011

The main goal of this paper is to construct three sets of road safety performance indicators, which are regional road safety performance indicators, urban road safety performance indicators and highway safety performance indicators, respectively. Fuzzy Delphi Method and Grey Delphi Method are applied to quantify experts' attitudes to regional road safety, urban road safety and highway safety. Comparing the results of two methods, the different results of two methods are analyzed, and then the final safety performance indicators are obtained by taking the intersection of results of two methods. Finally, three sets of performance indicators are constructed, which can be described and evaluated the safety level of region, urban road and highway, respectively. The research findings show that the method used in this paper is feasible and practical and can be provided as a reference for the administrative authority of road safety. © 2010 Elsevier Ltd. All rights reserved. Source

Liu T.,Dongbei University of Finance and Economics | Yan T.-C.,Chinese Peoples Public Security University
Journal of Natural Disasters | Year: 2011

Natural disasters has been with the human society, and caused huge economic losses, especially meteorological disasters. According to statistics of relevant departments of China, meteorological disaster losses account for around 70% or more among the various types of natural disasters. China's major meteorological disasters affect about four hundred million person times, economic losses that the disasters made accounted for roughly about 1 % -3% of the gross domestic product. In the recent half century, the major meteorological disasters in China made hundreds of million of people suffer; the caused direct economic losses were as much as several hundred billion. So, this paper intends to summarize main meteorological disasters and economic losses. It can be seen as important reference to understand meteorological disasters and their impact in China. Source

Duan W.J.,Beijing Normal University | Lu S.H.,Beijing Normal University | Lu S.H.,Chinese Peoples Public Security University | Wu Z.L.,Beijing Normal University | Wang Y.S.,Beijing Normal University
Journal of Physical Chemistry C | Year: 2012

NiO nanoparticles with sizes of 3.5-12.4 nm were grown by thermal decomposing of nickel acetate at different temperatures in NaCl and Li 2CO3 alkalisalts. The properties of the nanoparticles were characterized by X-ray diffraction spectrometer, transmission electron microscope, absorption spectrometer, micro-Raman microscope, and superconducting quantum interference device. The effects of the nanoparticle sizes on the crystal structure, exciton ground state energy, vibration modes, and magnetic properties were studied. Lattice parameter of NiO increases with a decrease in nanoparticle sizes. The band gap of NiO nanoparticles increases with a decrease in the nanoparticle size. LO modes of NiO nanoparticles shift red, and the intensity increases with a decrease in the nanoparticle sizes. Surface phonon modes are observed. Bifurcation temperature and blocking temperature of NiO nanoparticles shift to lower temperature with a decrease in nanoparticle sizes. Two peaks are present in all nanoparticles' zero-field-cooled magnetization curves, and the saturation magnetization, remanet magnetization, and coercivity increase with a decrease in the nanoparticle sizes. The nanoparticles exhibit size-dependent anomalous magnetic properties that make the remagnetization curve surpass the initial magnetization curve in the M-H hysteresis curves taken at 5 K. © 2012 American Chemical Society. Source

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