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Real-Time Rendering of Large-Scale Ocean Environments

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Computer Aided Drafting,Design and Manufacturing 2015年第2期25卷 47-53页

作者： HUANG jing-jia LI Sheng LAI Shun-nan WANG Guo-ping Peking University Shenzhen Graduate School Beijing Engineering Technology Research Center of Virtual Simulation and Visualization Peking University Beida (Binhai) Information Research

Simulation and rendering of large-scale natural environments, especially the ocean, has always been one of the hot issues in computer graphics, which can provide realism for various applications such as computer game, movie and military usage. Simulation of ocean environment is often lack of realism for real-time application due to its complexity of dynamic waves. In this paper, a method based on FFT Wave model is proposed to solve this problem, which can also simulate the ocean optic property with atmosphere scattering. Furthermore, our method has a lot of advantages including global ocean dataset support, real-time, dynamic reflection of ocean, the foam on the wave, smooth transition from deep ocean to seacoast, etc. The experimental results demonstrate the realism and effectiveness of our approach.

关键词： FFT wave model real-time rendering reflection refraction foam

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构建我国环境税收制度体系的理性思考

特区经济 2005年第8期 130-132页

作者：贾敬全淮北煤炭师范学院政法系

经济与地球生态环境之间日益紧张的关系,造成经济损失不断增加.要想使经济保持持续发展,必须尊重生态原理所形成的经济政策才能成功.达到目的的简单途径是让市场反映生态学原理,把各种经济活动的环境成本体现出来.为保护和改善环境质量... 详细信息

经济与地球生态环境之间日益紧张的关系,造成经济损失不断增加.要想使经济保持持续发展,必须尊重生态原理所形成的经济政策才能成功.达到目的的简单途径是让市场反映生态学原理,把各种经济活动的环境成本体现出来.为保护和改善环境质量,维护生态平衡,保证自然资源的永续利用、经济可持续发展,构建适合我国国情的环境保护税制迫在眉睫.

关键词：环境税收制度体系中国环境质量可持续发展消费税

Radix Achyranthis Bidentatae improves learning and memory capabilities in ovariectomized rats

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Neural Regeneration Research 2013年第18期8卷 1644-1654页

作者： Yuefen Wang Ya Xu Yanshu Pan Weihong Li Wei Zhang Yang Liu jing jia Pengtao Li Department of Encephalopathy Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine Department of Basic Chinese Medicine School of Basic Medical Sciences Beijing University of Chinese Medicine Pathology Room Department of Human Morphology School of Basic Medical Sciences Beijing University of Chinese Medicine Medical Comprehensive Course Teaching Center School of Basic Medical Sciences Beijing University of Chinese Medicine Anatomy Room Department of Human Morphology School of Basic Medical Sciences Beijing University of Chinese Medicine

Kidney-tonifying recipe can reduce the accumulation of advanced glycation end products, prevent neuronal degeneration and improve cognitive functions in ovariectomized rats. Radix Achyranthis Bidentatae alcohol extracts may dose-dependently inhibit non-enzymatic saccharification in vitro. This study aimed to examine the effect of Radix Achyranthis Bidentatae on advanced glycation end products and on learning and memory capabilities in ovariectomized rats. Ovariectomized rats were treated with Radix Achyranthis Bidentatae alcohol extracts （containing 1.5 g/kg crude drug） or 0.1% aminoguanidine for 12 weeks and behavioral testing was performed with the Y-electrical maze. This test revealed that Radix Achyranthis Bidentatae and aminoguanidine could improve the learning and memory capabilities of ovariectomized rats. Results of competitive enzyme-linked immunosorbent assay showed that treatment with Radix Achyranthis Bidentatae or aminoguanidine reduced the accumulation of advanced glycation end products in the frontal cortex of ovariectomized rats, while increasing content in the blood and urine. Biochemical tests showed that treatment with Radix Achyranthis Bidentatae or aminoguanidine decreased superoxide dismutase activity in the serum and frontal cortex, and increased serum levels of glutathione peroxidase in ovariectomized rats. In addition there was no apparent effect on malondialdehyde levels. These experimental findings indicate that Radix Achyranthis Bidentatae inhibits production of advanced glycation end products and its accumulation in brain tissue, and improves learning and memory capabilities in ovariectomized rats. These effects may be associated with an anti-oxidative action of the extract.

关键词： neural regeneration traditional Chinese medicine Alzheimer's disease Radix Achyranthis Bidentatae ovariectomy advanced glycation end products cognition learning and memory oxidative stress grants-supported paper neuroregeneration

Optical Pulse Compression Based on High-doped Erbium Fiber Amplifier and Standard Single-mode Fiber

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Semiconductor Photonics and Technology 2008年第2期14卷 90-94页

作者： REN jing jia Dong-fang LIU Yang LI Ya-bin Optoelectronic Information Science and Technology Lab College of PrecisionInstrument and Optoelectronics Engineering Tianjin University Tianjin 300072 CHN

Proposed is a novel optical pulse compression technique based on high-doped erbium fiber amplifier and standard single-mode fiber(SMF). We used the amplifier with the erbium ion concentration of 6.3×10-3 to amplify a hyperbolic secant pulse from a regeneratively mode-locked fiber laser. The central wavelength, pulsewidth and peak power of the pulse are 1 550 nm, 12.5 ps and 3 mW, respectively. Then the amplified pulse with peak power level corresponding to a higher-order soliton is compressed when it propagates through a 3-km-long single-mode fiber. Studied are the compressed pulses under different pump powers and fiber lengths. The results show that it can get a narrower pulse, and solve the difficulty that pulses at low power can not be compressed directly in the fiber. And the construct is compact.

关键词： high-doped erbium fiber amplifier soliton single mode fiber(SMF) pulse compression

考虑重力影响的柔性关节空间机械臂任务空间神经网络控制

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宇航学报 2015年第12期36卷 1391-1397页

作者：刘福才高静方贾晓菁燕山大学工业计算机控制工程河北省重点实验室秦皇岛066004

针对柔性关节空间机器人地面模拟及空间应用受到重力或微重力不确定项干扰的问题,提出一种基于奇异摄动的任务空间神经网络自适应控制算法。首先建立了考虑重力影响的柔性关节空间机器人的模型,通过奇异摄动方法将系统降阶处理后,转换... 详细信息

针对柔性关节空间机器人地面模拟及空间应用受到重力或微重力不确定项干扰的问题,提出一种基于奇异摄动的任务空间神经网络自适应控制算法。首先建立了考虑重力影响的柔性关节空间机器人的模型,通过奇异摄动方法将系统降阶处理后,转换到任务空间进行控制器的设计,利用神经网络自适应算法对系统的不确定性进行逼近,并针对逼近误差设计了鲁棒控制器补偿,最后将控制量转换为关节空间的控制力矩。对系统进行了稳定性分析和仿真校验,结果表明,控制器可以解决柔性带来的系统高频谐振和失稳问题,并能有效抵抗系统扰动,具有很好的跟踪性能。

关键词：柔性关节重力影响 RBF神经网络奇异摄动任务空间

Prognostic significance of the Neutrophil to Lymphocyte Ratio in colon and rectal cancer

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Prognostic significance of the Neutrophil to Lymphocyte Rati...

交叉持股是否导致收益的可预测性?——基于有限注意的视角

2017年中国肿瘤标志物学术大会暨第十一届肿瘤标志物青年科学家论坛

作者： Lin Wang jing jia Lu Lin Xingming Ye andYing Chen Fujian Provincial Cancer Hospital the Affiliated Cancer Hospital of Fujian Medical University

Objective Neutrophil-lymphocyte ratio(NLR) andplatelet-lymphocyte ratio(PLR)are systemic inflammation markers that have a proven prognostic role in many types of cancer. The aim of this study was to investigate potential diagnostic values of NLR and PLR in colorectal cancer patients, and analyze differences in pathological features of patients with right colon, left colon and rectalcancer. Methods A total of 1199 colorectal cancer patients were enrolled in this study. The patient characteristics and pretreatment data of hematological parameters, clinical TNM stages and available pathological features were *** association of NLR, PLR with clinicopathologic features and survival was evaluated. Results :Levels of NLR and PLR in the colon cancer were significantly higher than them in the rectal *** NLR(>2.631) was a statistically significant poor predictive factor for the overall survival(OS)(P=0.007) in late or advanced stage(III/IV) with colorectal cancer, but not PLR. The OS(P=0.032) of patients with well or moderate differentiated(G1/G2) also was significantly different according to *** addition,high NLRwas a poor predictive factor for the OS(HR, 1.579;95% CI, 1.061 to 2.348;P=0.0242) in colon cancer, but not for rectal *** with right colon cancer had a decreased OS compare to left colon, but no significant difference was observed. However, right colon was significantly associated with worse OS(P=0.021)than left colon in stage III/IV. Conclusion :NLR is a potential prognostic markerin colon cancer. Right colon cancer was significantly associated with worse OS than left colon in stage III/IV.

关键词： Colorectal cancer Survival Location Neutrophil-to-lymphocyte ratio (NLR) Platelet-tolymphocyte ratio(PLR)

来源： cnki会议评论

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系统工程理论与实践 2013年第7期33卷 1753-1761页

作者：饶育蕾彭叠峰贾文静中南大学商学院长沙410083

选取从2005-2008年的A股交叉持股上市公司为研究样本,发现被持股公司(子公司)股票的历史收益与持股公司(母公司)股票的当期收益存在显著的正相关性.通过构建按月调整的零投资组合,发现该投资策略可以获得2.01%的月超额收益率,在控制了... 详细信息

选取从2005-2008年的A股交叉持股上市公司为研究样本,发现被持股公司(子公司)股票的历史收益与持股公司(母公司)股票的当期收益存在显著的正相关性.通过构建按月调整的零投资组合,发现该投资策略可以获得2.01%的月超额收益率,在控制了风险因子和公司特征之后依然是显著的.进一步地,用公司规模、历史收益、换手率、是否被同一只基金所持有等来衡量投资者的注意力,发现交叉持股动量收益的显著性对注意力代理变量是比较敏感的,这恰好与有限注意假说一致.

关键词：交叉持股收益可预测性有限注意

采用形态小波变换原理的超高速故障选相算法研究

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电力系统保护与控制 2011年第15期39卷 57-63页

作者：李勋龚庆武贾晶晶武汉大学电气工程学院湖北武汉430072

提出一种形态滤波与小波变换相结合的超高速故障选相方法。该方法首先将故障相量通过凯伦贝尔变换转换成模故障分量,然后用形态滤波器滤除大部分噪声干扰,再采用小波变换求取各模量的模极大值,最后根据各模量模极大值特征构造一种新型... 详细信息

提出一种形态滤波与小波变换相结合的超高速故障选相方法。该方法首先将故障相量通过凯伦贝尔变换转换成模故障分量,然后用形态滤波器滤除大部分噪声干扰,再采用小波变换求取各模量的模极大值,最后根据各模量模极大值特征构造一种新型的故障选相元件。用该方法实现的选相元件能够克服传统选相元件的不足,具有超高速特点,且不受过渡电阻及系统运行方式的影响,选相结果准确、可靠。通过大量仿真结果证明了该选相元件的有效性与正确性。

关键词：电力系统数学形态学小波变换模极大值故障选相超高速保护

A WEIGHTED ITERATIVE METHOD FOR ROBUST SELF-CALIBRATION

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Journal of Electronics(China) 2006年第5期23卷 713-717页

作者： Liu Shigang Wu Chengke Tang Li jia jing National Key Laboratory of ISN Xidian University Xi＇an 710071 China

A robust self-calibration method is presented, which can efficiently discard the outliers based on a Weighted Iteration Method (WIM). The method is an iterative process in which the projective reconstruction is obtained based on the weights of all the points, whereas the weights are defined in inverse proportion to the re- ciprocal of the re-projective errors. The weights of outliers trend to zero after several iterations, and the accu- rate projective reconstruction is determined. The location of the absolute conic and the camera intrinsic pa- rameters are obtained after the projective reconstruction. The theory and experiments with both simulate and real data demonstrate that the proposed method is very efficient and robust.

关键词： Weight iteration Self calibration Projective reconstruction