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OPTIMAL MULTI-ASSET INVESTMENT WITH NO-SHORTING CONSTRAINT UNDER MEAN-VARIANCE CRITERION FOR AN INSURER

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Journal of Systems Science & Complexity 2011年第2期24卷 291-307页

作者： Junna BI Junyi guo lihua BAI School of Mathematical Sciences Nankai University Tianjin 300071 China.

This paper considers the optimal investment strategy for an insurer under the criterion of mean-variance. The risk process is a compound Poisson process and the insurer can invest in a risk-free asset and multiple risky assets. This paper obtains the optimal investment policy using the stochastic linear quadratic （LQ） control theory with no-shorting constraint. Then the efficient strategy （optimal investment strategy） and efficient frontier are derived explicitly by a verification theorem with the viscosity solution of Hamilton-Jacobi-Bellman （HJB） equation.

关键词： HJB equation mean-variance portfolio selection optimal investment verification theorem viscosity solution.

Knowledge transferred adaptive filter pruning for CNN compression and acceleration

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Science China(Information Sciences) 2022年第12期65卷 315-316页

作者： lihua guo Dawu CHEN Kui JIA School of Electronic and information Engineering South China University of Technology

Dear editor,It is necessary to compress the convolutional neural network(CNN) for resource-constrained devices deployment, resulting in accelerated model training and inference. “Soft” filter pruning(SFP) [1] conducts dynamic pruning operations during training time, allowing updates of the pruned filters to compensate for any possible misoperation. However,

关键词： Information Systems and Communication Service

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Two-stage local constrained sparse coding for fine-grained visual categorization

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Science China(Information Sciences) 2018年第1期61卷 273-275页

作者： lihua guo Chenggang guo Lei LI Qinghua HUANG Yanshan LI Xuelong LI School of Electronic and Information Engineering South China University of Technology College of Information Engineering Shenzhen University The Center for OPTical IMagery Analysis and Learning (OPTIMAL) State Key Laboratory of Transient Optics and PhotonicsXi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences

Fine-grained visual categorization(FGVC)[1,2]classifies the objects into categories which are both visually and semantically ***,the FGVC has included many species,i.e.,flowers,birds,and *** these species,all categori... 详细信息

关键词： HOG Two-stage local constrained sparse coding for fine-grained visual categorization HMP

Asymmetric Cationic [P, O] Type Palladium Complexes in Olefin Homopolymerization and Copolymerization

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Chinese Journal of Chemistry 2017年第8期35卷 1209-1221页

作者： Shuoyan Xiong lihua guo Shumiao Zhang Zhe Liu Key Laboratory of Soft Matter Chemistry Chinese Academy of Sciences Department of Polymer Science and Engineering University of Science and Technology of China Hefei Anhui 230026 China Shool of Chemistry and ChemtcalEngmeermg Qufu Normal University Qufu Shandong 273165 China

Metal-catalyzed ethylene homopolymerization and ethylene-polar monomer copolymerization to produce new kinds of polyolefins with novel microstructures are of great interest. So far, there are some disadvantages for traditional transition metal catalyst systems. Therefore, it is critical to develop new catalysts or alternative strategies. In recent years, some cationic [P, O] palladium complexes have been demonstrated with the abilities to obtain oligomers and the high molecular weight polymers. Most importantly, these complexes showed high activity and generated polymers with specific microstructures when used for copolymerization of ethylene with industrially relevant polar monomers. This review summarizes several types of high performance cationic [P, O] palladium catalysts in ethylene oligomerization, ethylene homopolymerization and the copolymerization of ethylene with polar monomers Specially, the regulation of steric and electronic effects at specific sites of the metal complexes was focused.

关键词： palladium olefin polymerization copolymerization cationic metal center substituent effect

A bioinspired bubble removal method in microchannels based on angiosperm xylem embolism repair

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Microsystems & Nanoengineering 2022年第2期8卷 237-247页

作者： lihua guo Yuanchang Liu Penghui Ran Gang Wang Jie Shan Xudong Li Chong Liu Jingmin Li Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalianChina Department of Mechanical Engineering University College LondonTorrington PlaceLondon WC1E 7JEUK

It is difficult to remove and eliminate bubbles in microchannels in many devices used in various biomedical fields,such as those needed for microfluidic immunoassays,point-of-care testing,and cell biology *** bubbles are associated with a number of negative outcomes,including a decrease in device sensitivity,inaccuracy of analysis results,and even functional *** conduits of angiosperm have the ability to remove bubbles in obstructed *** by such an embolism repair mechanism,this paper proposes a bioinspired bubble removal method,which exhibits a prominent ability to dissolve bubbles continuously within a large range of flow rates(2μL/min-850 plVmin)while retaining the stability and continuity of the flow without auxiliary *** a method also shows significant bubble removal stability in dealing with Newtonian liquids and non-Newtonian fluids,especially with high viscosity(6.76 Pa s)and low velocity(152 nL/min).Such advantages associated with the proposed bioinspired method reveal promising application prospects in macro/microfluidic fields ranging from 3D printing,implantable devices,virus detection,and biomedical fluid processing to microscale reactor operation and beyond.

关键词： bubble remove method

空频块编码正交频分复用水声通信中的超前正交匹配追踪稀疏信道估计

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哈尔滨工程大学学报 2022年第6期43卷 849-856页

作者：郭丽华哈尔滨学院黑龙江省地下工程技术重点实验室黑龙江哈尔滨150086

针对时变稀疏水声信道估计问题,本文提出了一种基于低复杂度、高精度的超前正交匹配追踪稀疏水声信道估计算法的空频块编码正交频分复用水声通信技术。利用超前迭代技术避免常规正交匹配追踪算法中的稀疏度未知条件下的性能下降问题;通... 详细信息

针对时变稀疏水声信道估计问题,本文提出了一种基于低复杂度、高精度的超前正交匹配追踪稀疏水声信道估计算法的空频块编码正交频分复用水声通信技术。利用超前迭代技术避免常规正交匹配追踪算法中的稀疏度未知条件下的性能下降问题;通过对分坐标下降迭代技术来降低超前正交匹配追踪算法中的最小二乘法矩阵求逆的运算负荷。仿真分析表明:本文提出的信道估计算法在归一化均方根误差上相比于传统的信道估计算法具有2 dB的性能增益,试验数据分析结果也验证了该结论,试验数据分析表明了提出的稀疏信道估计算法能够极大地提高空频编码正交频分复用系统的性能。

关键词：水声通信稀疏信道估计空频块编码空时块编码正交匹配追踪正交频分复用多普勒效应对分坐标下降信道均衡

Study on Innovation System and Innovation Strategy of Chinese Agricultural Product Processing Industry

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Chinese Business Review 2003年第2期2卷 33-45,77页

作者： Min Wang Mingyu Zhang lihua guo Northern Jiaotong Univ. School of Economics ＆ Management Northern Jiaotong Univ. Beijing lecturer in Northern Jiaotong Univ.

The agricultural product processing industry is the inevitable choice for the agriculture to realize the industrialization, integration and modernization. Although the agricultural product processing industry has become the bright point in Chinese economy development, the whole development level falls behind the developed countries. The thesis brings up that the inherent reasons that Chinese agricultural product processing industry falls behind is that Chinese agricultural product processing industry has not an integrated industrial innovation system and has not a proper innovation strategy. So this thesis deeply discusses how to construct innovation system of Chinese agricultural product processing industry and puts forward the innovation strategy in order to improve the technology innovation capability and the development level.

关键词： Innovation System Technology stride Agricultural product processing industry

Effects of phycocyanin on apoptosis and expression of superoxide dismutase in cerebral ischemia reperfusion injury

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Neural Regeneration Research 2006年第2期1卷 140-142页

作者： Meizeng Zhang lihua Wang Yunliang guo Institute of Cerebrovascular Diseases Medical College Hospitalof Qingdao University Qingdao266003 Shandong ProvinceChina

BACKGROUND ： The application of exogenous antioxidant is always the focus in the prevention and treatment of cerebral ischemia. Phycocyanin has the effects against oxidation and inflammation, but its role in the pathophysiological process of cerebral ischemia reperfusion injury still needs further investigation. OBJECTIVE： To observe the effects of phycocyanin on the expression of superoxide dismutase （SOD） apoptosis and form of the nerve cells in rats after cerebral ischemia reperfusion injury. DESIGN： A randomized control animal experiment SETTING ： Institute of Cerebrovascular Disease, Medical School Hospital of Qingdao University MATERIALS： Fifty-two healthy adult male Wistar rats of clean degree, weighing 220-260 g, were used. Phycocyanin was provided by the Institute of Oceanology, Chinese Academy of Sciences. METHODS： The experiments were carried out in Shangdong Key Laboratory for Prevention and Treatment of Brain Diseases from May to December 2005. ① All the rats were divided into three groups according to the method of random number table： sham-operated group （n=4）, control group （n=24） and treatment group （n=24）. Models of middle cerebral artery occlusion/reperfusion （MCAO/R） were established by the introduction of thread through external and internal carotid arteries in the control group and treatment group. After 1-hour ischemia and 2-hour reperfusion, rats in the treatment group were administrated with gastric perfusion of phy- cocyanin suspension （0.1 mg/g）, and those in the control group were given saline of the same volume, and no treatment was given to the rats in the sham-operated group. ②The samples were removed and observed at ischemia for 1 hour and reperfusion for 6 and 12 hours and 1, 3, 7 and 14 days respectively in the control group and treatment group, 4 rats for each time point, and those were removed at 1 day postoperatively in the sham-operated group. Forms of the nerve cells were observed with toluidine blue staining. Apoptosis

关键词： Effects of phycocyanin on apoptosis and expression of superoxide dismutase in cerebral ischemia reperfusion injury

Genomic and Phenotypic Diversity of Carbapenemase-Producing Enterobacteriaceae Isolates from Bacteremia in China: A Multicenter Epidemiological, Microbiological, and Genetic Study

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Engineering 2022年第5期8卷 90-100页

作者： Beiwen Zheng Hao Xu lihua guo Xiao Yu Jinru Ji Chaoqun Ying Yunbo Chen Ping Shen Huiming Han Chen Huang Shuntian Zhang Tao Lv Yonghong Xiao State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003China Medical College of Beihua University Jilin 132013China Department of Infectious Diseases Ningbo Medical Center Li Huili HospitalNingbo 315040China

Carbapenemase-producing Enterobacteriaceae(CPE) isolates are recognized as one of the most severe threats to public health. However, the population structure and genetic characteristics of CPE isolates among bloodstream infections(BSIs) are largely unknown. To address this knowledge gap, in this study,we included patients with clinically significant BSIs due to Enterobacterales isolates, recruited from 26 sentinel hospitals in China(2014–2015). CPE isolates were microbiologically and genomically characterized,including their susceptibility profiles, molecular typing, phylogenetic features, and genetic context analysis of carbapenemase-encoding genes. Of the 2569 BSI Enterobacterales isolates enrolled, 42(1.6%) were carbapenemase-positive. Moreover, among the 2242 investigated isolates, 1111(49.6%) extendedspectrum β-lactamase(ESBL)-producing isolates were identified in Escherichia coli(E. coli), Klebsiella pneumoniae(K. pneumoniae), Proteus mirabilis(P. mirabilis), and Klebsiella oxytoca. Whole genome sequencing analysis showed the clonal spread of K. pneumoniae carbapenemase(KPC)-2-producing K. pneumoniae sequence type(ST) 11 and New Delhi metallo-β-lactamase(NDM)-5-producing E. coli ST167 in our collection. Plasmid analysis revealed that carbapenemase-encoding genes were located on multiple plasmids. A high prevalence of biofilm-encoding type 3 fimbriae clusters and yesiniabactin-associated genes was observed in K. pneumoniae isolates. This work demonstrates the high prevalence of ESBLs and the wide dissemination of CPE among BSI isolates in China, which represent real clinical threats. Moreover, our findings first illustrate a more comprehensive genome scenario of CPE isolates among BSIs. The clonal spread of KPC-2-producing K. pneumoniae ST11 and NDM-5-producing E. coli ST167 needs to be closely monitored.

关键词： Carbapenemase Carbapenemase-producing Enterobacteriaceae Plasmid-mediated China Extended-spectrum b-lactamase