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Sensitivity analysis of the channel estimation deviation to the MAP decoding algorithm

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Frontiers of Electrical and Electronic Engineering in China 2006年第4期1卷 437-440页

作者： WAN Ke fan ping-zhi Institute of Mobile Communications Southwest Jiaotong UniversityChengdu 610031China

As a necessary input parameter for maximum a-posteriori(MAP)decoding algorithm,SNR is normally obtained from the channel estimation *** research indicated that SNR estimation deviation degraded the performance of Turbo decoding *** this paper,MAP decoding algorithm with SNR estimation de-viation was investigated in detail,and the degradation mechanism of Turbo decoding was explained *** theoretical analysis and computer simulation disclosed the specific reasons for the performance degradation when SNR estimation was less than the actual value,and for the higher sensitivity of SNR estimation to long-frame Turbo codes.

关键词： Turbo codes MAP decoding SNR estimation wireless communications

Effect of Land Cover Change on Soil Phosphorus Fractions in Southeastern Horqin Sandy Land, Northern China

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Pedosphere 2008年第6期18卷 741-748页

作者： ZHAO Qiong ZENG De-Hui fan zhi-ping D. K. LEE Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China） Graduate University of the Chinese Academy of Sciences Beijing 100039 （China） Department of Forest Sciences Seoul National University Seoul-151- 921 （Repubiic of Korea）

In the past 50 years, large areas of the Horqin sandy land were afforested to prevent desertification. Although the afforestation policy appears successful, many people now doubt whether it is suitable to plant trees with high density on the poor soils in semiarid regions. Little is known about the impacts of afforestation on the sandy soil properties, although the evaluation of these impacts is fundamental to judge the rationality of afforestation policy. Soil phosphorus （P） fractions, acid phosphomonoesterase activities, and other soil chemical properties were compared among five adjoining typical ecosystems on poor sandy soils in southeastern Horqin sandy land. The ecosystems studied are natural elm savanna, degraded grassland, Mongolian pine （Pinus sylvestris var. mongolica） plantation, Chinese pine （Pinus tabulaeformis） plantation, and mixed plantation of Mongolian pine and poplar （Populus simonii）. The results showed that organic P dominated soil P （47%-65%） was the principal source of available P. The degradation of elm savanna to grassland significantly reduced soil pH and resulted in an overall reduction in soil fertility, although slightly increased labile inorganic P. Grassland afforestation had no significant influence on soil pH, organic carbon, and total N but significantly reduced total P. Impacts of grassland afforestation on soil P fractions depended on tree species. Natural elm savanna had higher soil P conserving ability than artificial plantations. Therefore, with the aim of developing a sustainable ecosystem, we suggested that vegetations with low nutrient demand （particularly P） and efficient nutrient cycling would be more suitable for ecosystem restoration in the semiarid region.

关键词： afforestation Horqin sandy land soil phosphorus vegetation restoration

Applied technique of the cemented fill with fly ash and fine-sands

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Journal of Central South University 2001年第3期13卷 189-192页

作者： WANG Xin-ming,LI Jian-xiong,fan ping-zhi (College of Resources, Environment and Civil Engineering, Central South Universi ty, Changsha 410083, China) College of Resources Environment and Civil Engineering Central South University Changsha China

Traditional stabilization of backfilling material is done by using Portland cement. However, the high price of cement forced mining engineer s to seek cheaper binding materials. Fly ash, which is the indus- trial wast e from thermal power plant, possess the potential activity of jellification, and can b e used in cemented fill as a partial substitute for cement to reduce the fill co s t. Tests were done during the past few years in Xinqiao Pyrite Mine and Phoenix Copper Mine to determine the technology parameters and the suitable content of f ly ash. Specimens with different cement/fly/ash tailings (sands) ratios were tes ted to obtain the strength values of the fill mass based on the analyses of both the chemical composition and physical and mechanical properties of fly ash . The compressive strength of specimens with a ratio of 1∶2∶8 (cement to fly ash to tailings ) can reach 2 MPa after 90 d curing, totally meeting the requiremen t of artificial pillar and reducing the fill cost by 20%-30%.

关键词： fly ash cementing agent cemented fill replacement

Holographic superfluid ring with a weak link

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 29-38页

作者： zhi-Hong Li Huai-fan Li Department of Physics Shanxi Datong UniversityDatong 037009China Institute of Theoretical Physics Shanxi Datong UniversityDatong 037009China

We explore the generation of topological defects in the course of a dynamical phase transition in a ring with a weak link, i.e., a SSS Josephson junction, from the AdS/CFT correspondence. By setting different parameters of the junction(width, steepness,depth) and the final temperature of the quench, the configurations of the charge density and condensate of the order parameters of the dual field theory are presented. Meanwhile, we observe that in the final equilibrium state, variations in parameters of the junctions only affect the configurations of the charge density and condensate of the order parameters, without altering their values outside the junction. However, variations in the final temperature will directly affect the values of the charge density and condensate of the order parameters outside of the junction. Moreover, in the final equilibrium state, we propose an analytic relation between the gauge-invariant velocity in the two superconducting states in the SSS Josephson junction, which agrees well with the numerical results.

关键词： AdS/CFT correspondence holographic superfluid holographic Josephson junction

Ordered Bicontinuous Network Structures Regulated by Orientational Interactions in a Rod-Coil Block Copolymer

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Chinese Journal of Polymer Science 2024年第5期42卷 636-642,I0008页

作者： Xiao-Lin Lyu Shi-Chu Yang An-Qi Xiao ping-ping Hou Wei Zhang Hong-Bing Pan zhi-Hao Shen Xing-He fan Qi-Feng Zhou Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Key Laboratory of Advanced Materials Technologies International(HongKong Macao and Taiwan)Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou UniversityFuzhou350108China

The rich phase behavior of block copolymers(BCPs)has drawn great attention in recent ***,the double diamond(DD)phase is rarely obtained because of the competition between the minimization of interfacial energy and packing ***,a rod-coil BCP containing mesogen-jacketed liquid crystalline polymer is designed to acquire ordered bicontinuous network *** reduction of internal energy originating from the orientational interaction among the rod blocks can compensate for the free energy penalty of packing frustration to stabilize the DD *** resulting BCP can also experience lamellae-to-DD and double gyroid-to-lamellae transitions by changing the annealing *** results make the rod-coil BCP an excellent candidate for the self-assembly of ordered network structures,demonstrating great potential in nanopatterning and metamaterials.

关键词： Block copolymer Rod-coil Ordered bicontinuous phase Double diamond Double gyroid

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指标期望为随机变量情形的多指标决策方法

控制与决策 2015年第8期30卷 1434-1440页

作者：于超樊治平东北大学工商管理学院沈阳110004

针对指标期望为随机变量情形的多指标决策问题,提出一种决策分析方法.该方法首先通过计算指标值相对于指标期望的损益值,将决策矩阵转化为关于指标期望的损益矩阵;然后运用随机占优准则,通过判断针对每个指标两两方案之间的随机占优关系... 详细信息

针对指标期望为随机变量情形的多指标决策问题,提出一种决策分析方法.该方法首先通过计算指标值相对于指标期望的损益值,将决策矩阵转化为关于指标期望的损益矩阵;然后运用随机占优准则,通过判断针对每个指标两两方案之间的随机占优关系,进而构建两两方案的随机占优关系矩阵,并使用PROMETHEE II方法对方案进行排序;最后以某研究所移动硬盘采购问题为例,对所提出方法的实用性进行说明.

关键词：多指标决策指标期望随机变量随机占优方案排序

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考虑损失规避型供应商的VMI供应链协调

控制与决策 2016年第5期31卷 935-942页

作者：刘云志樊治平东北大学工商管理学院沈阳110819

给出损失规避型供应商和风险中性零售商组成的二级VMI供应链批发价格契约与协调的理论分析.主要结论是:损失规避型供应商的最优产品生产量可能小于(等于或大于)风险中性的供应商的最优产品生产量,且最优产品生产量为单位剩余产品净残值... 详细信息

给出损失规避型供应商和风险中性零售商组成的二级VMI供应链批发价格契约与协调的理论分析.主要结论是:损失规避型供应商的最优产品生产量可能小于(等于或大于)风险中性的供应商的最优产品生产量,且最优产品生产量为单位剩余产品净残值(单位缺货成本)的增函数、单位库存成本的减函数、一定条件下的单位批发价格(单位生产成本)的增函数或减函数;批发价格契约在一定条件下可使二级VMI供应链达到协调.

关键词：损失规避供应商管理库存供应链协调批发价格契约

基于前景理论的具有指标期望的多指标决策方法

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控制与决策 2015年第1期30卷 91-97页

作者：刘云志樊治平东北大学工商管理学院沈阳110004

针对决策者给出单一与组合指标期望情形的多指标决策问题,提出一种基于前景理论的决策分析方法.首先,依据前景理论将决策者给出的指标期望视为参照点,分别计算各方案针对各单一与各组合指标期望的前景价值,并构建各方案的综合前景价值向... 详细信息

针对决策者给出单一与组合指标期望情形的多指标决策问题,提出一种基于前景理论的决策分析方法.首先,依据前景理论将决策者给出的指标期望视为参照点,分别计算各方案针对各单一与各组合指标期望的前景价值,并构建各方案的综合前景价值向量;然后,将原始决策问题转化为相应的广义优序模糊约束满意问题(GPFCSP),进而计算各方案针对相应推理准则的总体满意度,并据此对各方案进行排序;最后,通过算例表明了该方法的可行性.

关键词：多指标决策指标期望前景理论广义优序模糊约束满意问题方案排序

Effect and mechanism of acute graft versus host disease on early diffuse murine lung injury following allogeneic stem cell transplantation

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Science China(Life Sciences) 2009年第11期52卷 1016-1022页

作者： NING Juan, LIU Qi Fa, LUO Xiao Dan, fan zhi ping & Zhang Yu Department of Hematology, Southern Hospital, Southern Medical University, Guang Zhou 510515, China Department of Hematology Southern Hospital Southern Medical University Guang Zhou China

To explore the effect and pathogenssis of acute graft-versus-host disease (aGVHD) on early diffuse lung injury in allogeneic hematopoietic stem cell transplantation (allo-HSCT), we established an aGVHD model of C57BL/6→BALB/c mice. Chest computed tomography (CT) scans, histopathology and the levels of cytokines including tumor necrosis factor α (TNFα) and Interferon (IFNγ) in lungs were dynamically detected in recipient mice after transplantation. The incidence of aGVHD was respectively 0%, 0% and 100% in simple irradiation group (A), syngeneic transplant group(B) and allogeneic transplant group (C). Chest CT scans of recipient mice were normal in 3 groups on days +3 and +7 after transplantation. CT showed that two of ten mice had bilateral lung diffuse infiltrate on day +12 (on the brink of death) in group A and 6 of 10 mice had bilateral lung diffuse infiltrate on day +14 (3 d after aGVHD occurring) in group C, and were normal on days +12 and +14 in group B after transplantation. Histopathology of lungs in the 3 groups was similar, consisting of minor interstitial pneumonitis on day +3. Group A showed edema, hyperplasia of epithelial cells and widened alveolar interval on day +7, and epithelial cell necrosis, lymphocyte infiltration, hemorrhage, protein leakage, and local consolidation on day +12. The histopathology of group B showed slight edema of epithelial cells on +7 day, which were slighter than that on day +3, and virtually normal on day +14. The histopathology in group C was characterized by the significant expansion and congestion of capillaries, and lymphocyte infiltration on day +7, the acute pneumonitis was present involving tissue edema, lymphocyte and macrophage infiltration, protein leakage and perivascular inflammation on day +14. In group A, the levels of TNFα were lower on day +7 than on day +3. In group B, the levels of TNFα attained a peak on day +3, which decreased on days +7 and +14. In group C, the levels of TNFα were highest on day +7 and t

关键词： lung injury acute graft-versus-host disease allogeneic hematopoietic stem cell transplantation