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Power control for two-way amplify-and-forward relaying over Rayleigh fading channels

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 280-287页

作者： Xing-zheng li yuan-an liu Gang XIE Pan-liang DENG Fang liu School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

We propose two novel power control policies for a two-way amplify-and-forward (AF) relaying system,in which each node (two sources and one relay) is assumed to operate under bothminimum and peak power *** the exploitation of instantaneous channel gains,the first policy can maximize the sum rate of the ***,the instantaneous channel gains may be unavailable in a rapid time-varying system,where the first policy is ***,a robust power control policy which requires only mean channel gains is proposed to maximize the upper bound of the average sum rate,and the properties of this policy are *** results show that,by comparison with the policy in which all the nodes use their peak transmit power,the proposed power control policies can provide considerable system performance ***,the performance difference between the two proposed policies is negligible when the relay is close to one source.

关键词： Amplify-and-forward (AF) relaying Power control Two-way relay channel Bidirectional relaying Cooperative communication

Some New Translation Surfaces in 3-Minkowski Space

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Journal of Mathematical Research and Exposition 2011年第6期31卷 1123-1128页

作者： yuan yuan Hui li liu Department of Mathematics Northeastern UniversityLiaoning 110004P.R.China

In this paper we study translation surfaces of some new types in 3-Minkowski space E13 and give some classifications of such surfaces whose mean curvature and Gauss curvature satisfy certain conditions.

关键词： Minkowski space translation surface Weingarten surface.

Clustering-triggered Emission of Cellulose and Its Derivatives

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Chinese Journal of Polymer Science 2019年第4期37卷 409-415,I0007页

作者： lin-lin Du Bing-li Jiang Xiao-Hong Chen Yun-Zhong Wang lin-Min Zou yuan-li liu Yong-Yang Gong Chun Wei Wang-Zhang yuan Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Ministry of EducationCollege of Materials Science and EngineeringGuilin University of Technology College of Pharmacy Guilin Medical University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University

In recent years, nonconventional luminogens free of aromatic groups have attracted extensive attention due to their academic importance and promising wide applications. Whilst previous studies generally focused on fluorescence from aliphatic amine or carbonylcontaining systems, less attention has been paid to room temperature phosphorescence(RTP) and the systems with predominant oxygen functionalities. In this work, photophysical properties of the polyhydroxy polymers, including microcrystalline cellulose(MCC), 2-hydroxyethyl cellulose(HEC), hydroxypropyl cellulose(HPC), and cellulose acetate(CA), were studied and compared. While MCC,HEC, and HPC solids showed bright emission alongside distinct RTP, CA demonstrated relatively low intensity of solid emission without noticeable RTP. Their emissions were explained in terms of the clustering-triggered emission(CTE) mechanism and conformation rigidification. Additionally, on account of its intrinsic emission, concentrated HEC aqueous solution could be used as the probe for the detection of 2,4,6-trinitrophenol(TNP).

关键词： Cellulose Nonconventional luminogens Room temperature phosphorescent Clustering-triggered emission

Microstructure and Corrosion Behavior of Friction Stir Welded Al Alloy Coated by In Situ Shot-Peening-Assisted Cold Spray

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 172-182页

作者： Hua Zhang Chang-Yu Zhao Qi-Long Guo Rui-Sheng Yang li-yuan liu San-Bao lin School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Beijing Institute of Astronautical Systems and Engineering Beijing 100076China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

To improve the corrosion resistance of friction stir welded(FSW)joints,in situ shot-peening-assisted cold spray coating was applied to the surface of FSW *** microstructure and corrosion behavior of the coatings were *** results showed that a dense coating was obtained by cold spraying ***,the use of in situ shot-peeningassisted technology significantly reduced the porosity of the coating,which has a positive impact on the microstructure and the mechanical *** corrosion tests showed that the coating aff ected positively on the corrosion *** the coated surface,the craters caused by shot-peening particles were corroded in the form of exfoliation corrosion,while the exposed particles were corroded in the form of intercrystalline *** work provides a new approach to the corrosion protection of FSW joints.

关键词： Aluminum alloy coating Cold spray Friction stir welding In situ shot-peening Intergranular corrosion

Mitigation of greenhouse gases released from mining activities:A review

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 513-521页

作者： li-yuan liu Hong-guang Ji Xiang-feng Lü Tao Wang Sheng Zhi Feng Pei Dao-lu Quan Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Department of Energy and Mineral Engineering EMS Energy Institute and G3 CenterPennsylvania State UniversityUniversity ParkPA 16802USA

Climate changes that occur as a result of global warming caused by increasing amounts of greenhouse gases(GHGs)released into the atmosphere are an alarming *** greenhouse gas emissions is critically important for the current and future status of mining *** mining industry is one of the significant contributors of greenhouse *** essence,anthropogenic greenhouse gases are emitted directly during the actual mining and indirectly released by the energy-intensive activities associated with mining equipment,ore transport,and the processing ***,we reviewed both direct and indirect GHG emissions to analyze how mining contributes to climate *** addition,we showed how climate change impacts mineral *** assessment was performed using a GHG inventory model for the gases released from mines undergoing different product life *** also elucidate the key issues and various research outcomes to demonstrate how the mining industry and policymakers can mitigate GHG emission from the mining *** review concludes with an overview of GHG release reduction and mitigation strategies.

关键词： greenhouse gas emission greenhouse gas reduction mining climate change life cycle assessment mitigation strategy

RADAR HRRP RECOGNITION BASED ON THE MINIMUM KULLBACK-LEIBLER DISTANCE CRITERION

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Journal of Electronics(China) 2007年第2期24卷 199-203页

作者： yuan li liu Hongwei Bao Zheng Key Lab for Radar Signal Processing Xidian University Xi＇an 710071 China

To relax the target aspect sensitivity and use more statistical information of the High Range Resolution Profiles (HRRPs), in this paper, the average range profile and the variance range profile are extracted together as the feature vectors for both training data and test data representa-tion. And a decision rule is established for Automatic Target Recognition (ATR) based on the mini-mum Kullback-Leibler Distance (KLD) criterion. The recognition performance of the proposed method is comparable with that of Adaptive Gaussian Classifier (AGC) with multiple test HRRPs, but the proposed method is much more computational efficient. Experimental results based on the measured data show that the minimum KLD classifier is effective.

关键词： High Range Resolution Profile (HRRP) Automatic Target Recognition (ATR) Kullback-Leibler Distance (KLD) Adaptive Gaussian Classifier (AGC)

Basic and clinical research into chronic obstructive pulmonary disease in China

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Chinese Medical Journal 2010年第4期123卷 491-497页

作者： li yuan-yuan liu Xian-sheng XU Yong-jian Department of Respiratory Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Chronic obstructive pulmonary disease （COPD）, one of the most common public health problemsworldwide, is the fourth leading cause of death in the world. In China, respiratory diseases （of which COPD is a major component） are the third leading cause of death in rural areas and the fourth leading cause of death in urban area, accounting for 1 million deaths and over 5 million disabilities each year. COPD ranks first among the burdens in China.1 Hence, medical workers and governments at different levels pay close attention to this disease~ The Respiratory Group under the Chinese Medical Association published the Guidelines for Diagnosis and Management of COPD in 2002^2 and the revised version in 2007^3. This publication serves as a milestone of the development of basic and clinical investigation in China. The guidelines are likely to affect the way for the treatment of COPD in addition to reflect the current knowledge about the underlying causes of COPD and recommend the proper diagnosis and management of COPD.

关键词： pulmonary disease, chronic obstructive prevalence risk factors etiology therapy China

Comprehensive silk gland multi-omics comparison illuminates two alternative mechanisms in silkworm heterosis

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Zoological Research 2022年第4期43卷 585-596页

作者： Han Xu Lei Chen Xiao-ling Tong Hai Hu li-yuan liu Gui-Chun liu Ya-Nan Zhu Ruo-Ping Zhao Wen Wang Fang-Yin Dai Xin li Hui Xiang School of Medicine Shenzhen Campus of Sun Yat-Sen UniversityShenzhenGuangdong 518107China Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Guangzhou Key Laboratory of Insect Development Regulation and Application ResearchInstitute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouGuangdong 510631China School of Ecology and Environment Northwestern Polytechnical UniversityXi’anShaanxi 710072China State Key Laboratory of Silkworm Genome Biology Key Laboratory of Sericultural Biology and Genetic BreedingMinistry of Agriculture and Rural AffairsCollege of BiotechnologySouthwest UniversityChongqing 400715China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China

Heterosis is a common phenomenon in plants and animals with diverse underlying ***,we applied two widely used silkworm hybrid systems and performed multi-omics analysis to identify possible intrinsic associations between different hybrid strategies and epigenetic mechanisms with silkworm *** found significant differences in the silk gland transcriptomic landscape between the two systems,including differentially expressed genes and expression patterns in the hybrid offspring compared to their *** the quaternary hybrid system,hybrid vigor was primarily due to upregulated genes and the parent-dominant upregulated expression pattern,involving multiple transport processes,cellular nitrogen compound catabolism,glucose metabolism,and tricarboxylic acid *** the binary system,hybrid vigor was mainly due to the down-regulated genes and transgressively down-regulated expression pattern,mainly involving basic nitrogen synthesis metabolism and body *** also demonstrated that DNA methylation may affect hybrid vigor by regulating the expression of several heterosis-related ***,this study revealed two alternative mechanisms that may contribute to silkworm heterosis,both of which facilitate the efficient utilization of energy and nitrogen for silk production.

关键词： Heterosis Silkworm Hybrid systems Multi-omics Silk production

Unconjugated bilirubin alleviates experimental ulcerative colitis by regulating intestinal barrier function and immune inflammation

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World Journal of Gastroenterology 2019年第15期25卷 1865-1877页

作者： Jia-Dong Zheng Yan He Heng-yuan Yu yuan-li liu Yi-Xuan Ge Xue-Ting li Xue li Yan Wang Meng-Ru Guo Yi-lin Qu Xiao-Fa Qin Ming-Shan Jiang Xiu-Hong Wang Department of Biochemistry and Molecular Biology Heilongjiang Provincial Science and Technology Innovation Team in Higher EducationInstitutes for Infection and Immunity Harbin Medical University GI Biopharma Inc. Department of General Surgery the Second Affiliated Hospital of Harbin Medical University

BACKGROUND Unconjugated bilirubin(UCB) is generally considered toxic but has gained recent prominence for its anti-inflammatory properties. However, the effects of it on the interaction between intestinal flora and organisms and how it influences immune responses remain *** To investigate the role of UCB in intestinal barrier function and immune inflammation in mice with dextran-sulfate-sodium-induced *** Acute colitis was induced by 3%(w/v) dextran sulfate sodium salt in drinking water for 6 d followed by untreated water for 2 d. Concurrently, mice with colitis were administered 0.2 mL UCB(400 μmol/L) by intra-gastric gavage for 7 *** activity index(DAI) was monitored daily. Mice were sacrificed at the end of the experiment. The length of the colon and weight of the spleen were recorded. Serum level of D-lactate, intestinal digestive proteases activity, and changes to the gut flora were analyzed. In addition, colonic specimens were analyzed by histology and for expression of inflammatory markers and *** Mice treated with UCB had significantly relieved severity of colitis, including lower DAI, longer colon length, and lower spleen weight(colon length: 4.92 ±0.09 cm vs 3.9 ± 0.15 cm; spleen weight: 0.33 ± 0.04 vs 0.74 ± 0.04, P < 0.001). UCB administration inactivated digestive proteases(chymotrypsin: 18.70 ± 0.69 U/g vs44.81 ± 8.60 U/g; trypsin: 1.52 ± 0.23 U/g vs 9.05 ± 1.77 U/g, P < 0.01), increased expression of tight junction(0.99 ± 0.05 vs 0.57 ± 0.03, P < 0.001), decreased serum level of D-lactate(31.76 ± 3.37 μmol/L vs 54.25 ± 1.45 μmol/L, P < 0.001), and lowered histopathological score(4 ± 0.57 vs 7 ± 0.57, P < 0.001) and activity of myeloperoxidase(46.79 ± 2.57 U/g vs 110.32 ± 19.19 U/g, P < 0.001). UCB also regulated the intestinal microbiota, inhibited expression of tumor necrosis factor(TNF) α and interleukin 1β(TNF-α: 52.61 ± 7.81 pg/mg vs 105.04 ± 11.92 pg/mg,interleukin 1β: 13.43 ± 1.68 vs 32.41 ± 4.62 pg/mg,

关键词： Ulcerative colitis Unconjugated bilirubin Intestinal barrier Intestinal homeostasis Digestive proteases Inflammation