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Research on the novel discretized ratio control strategies and hardware-in-the-loop test for continuous variable transmission system

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第3期10卷 43-64页

作者： Deng Tao li zhifei Yin Yanli School of Mechantronics&Vehicle Engineering Chongqing Jiaotong University Chongqing 400074P.R.China

Based on traditional continuous control strategy for Continuously Variable Transmission(CVT)ratio,according to the principles of shift control strategy for stepped automatic transmission,the influences of throttle opening and external resistance or vehicle speed on CVT ratio control are analyzed on bumpy *** the same variation of external resistance condition,the differences between optimal economic control strategy and optimal dynamic control strategy are ***,the traditional continuous optimal dynamic and economic control lines are divided into multi-step upshift ***,the corresponding downshift points are set to avoid the interference near shift *** that,the novel discretized ratio control methods for CVT system are *** respectively discretizing throttle opening and vehicle speed,the discretized ratio control strategy for throttle opening,and the integrated discretized ratio control strategy for throttle opening and vehicle speed are further proposed and ***,the hardware-in-the-loop(HIL)test system is built to further verify the feasibility and accuracy of discretized ratio control *** simulation and HIL test results show that the sensitivity of throttle opening and vehicle speed to ratio control is reduced dramatically,the fluctuation of ratio is decreased considerably,the transmission efficiency is increased significantly,and the jerk is declined moderately.

关键词： Continuously Variable Transmission(CVT) discretized ratio control simulation hardware-in-the-loop(HIL)test

A Differential BPSO-GA Hybrid Algorithm for Discrete Combination Optimization 36

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A Differential BPSO-GA Hybrid Algorithm for Discrete Combina...

21世纪以来中国的水资源安全研究——李志斐研究员访谈

第36届中国控制会议

作者： Yimin Zhou zhifei li Chaofang Hu Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences The Chinese University of Hong Kong Tianjin University

ISBN: (纸本)9781538629185

There are a lot of typical statistical problems in discrete combination optimization, including integer linear programming, covering problem, knapsack problem, graph theory, network flow and dispatching. As for the NPC（Non-deterministic Polynomial complete） problems, many algorithms have been developed for the discrete optimization where the heuristic algorithm is one kind of the important and effective methods. In this paper, a new swarm intelligent algorithm is proposed, combined with BPSO（Binary Particle Swarm Optimization）, GA（Genetic Algorithm） and maximum difference calculation, to solve the TSP and Knapsack two typical discrete combination optimal problems. The proposed algorithm can search the historical memory and differentiated search strategy is introduced to keep the diversity of the group so as to select the elite gene features as the candidates. Experiments are designed and performed to analyze the convergence of the algorithm and the solutions are obtained in high-dimensional searching space. As for the binary combination problem, results demonstrate that the developed algorithm has faster convergence speed and higher quality compared to the traditional swarm intelligent algorithms.

关键词： Combination optimization Particle swarm optimization Genetic algorithm Traveling salesman problem Knapsack problem

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国际政治研究 2023年第2期44卷 136-159,8页

作者：李志斐刘磊中国社会科学院亚太与全球战略研究院中国社会科学院亚太与全球研究院

水资源是事关人类生存和国家可持续发展的战略性自然资源。进入21世纪后,随着水资源稀缺性危机的加剧,水资源安全对于国际关系和地缘政治的影响更加明显,水资源安全治理成为全球安全治理的重要内容。那么,水资源安全如何影响国家间关系... 详细信息

水资源是事关人类生存和国家可持续发展的战略性自然资源。进入21世纪后,随着水资源稀缺性危机的加剧,水资源安全对于国际关系和地缘政治的影响更加明显,水资源安全治理成为全球安全治理的重要内容。那么,水资源安全如何影响国家间关系和地区环境?为何在21世纪水资源安全会成为国际研究热点议题?国内外国际关系领域的水资源安全研究有哪些进展?未来的发展趋势是什么?中国学界的水资源安全研究取得了哪些成绩?还有哪些不足?未来应采取哪些积极举措推动中国学界水资源安全研究的深化?为此,本刊特邀记者中国社会科学院亚太与全球研究院刘磊专访中国社会科学院亚太与全球战略研究院研究员李志斐。李志斐研究员的主要研究方向为水资源安全与国际关系、亚太地区非传统安全、中国周边安全,著有《亚太地区水资源安全治理》《水与中国周边关系》《国际河流河口:地缘政治和中国权益思考》等。

关键词：水资源安全中国社会科学院国际关系领域非传统安全地缘政治资源稀缺性国家间关系周边关系

Effect of Bioactive Peptides(BPs) on the Development of Pacific White Shrimp(litopenaeus vannamei Boone, 1931)

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Journal of Ocean University of China 2016年第3期15卷 495-501页

作者： WANG Guangjun YU Ermeng li zhifei YU Deguang WANG Haiying GONG Wangbao Key Laboratory of Tropical & Subtropical Fish Breeding & Cultivation of Chinese Academy of Fishery Sciences Pearl River Fisheries Research Institute

The present study was conducted to evaluate the feasibility of replacing fish meal(FM) with bioactive peptides(BPs) in diet of white shrimp(litopenaeus vannamei). The changes in growth performance, body composition, non-specific immunity, and water quality were examined after the shrimp were fed four diets, in which 0%(control), 33.3%, 66.7% and 100% of FM was replaced by BPs, respectively. The groups were designated as Con, 1/3BPs, 2/3BPs, and 3/3BPs. A total of 720 shrimp with an initial body weight of 1.46 ± 0.78 g were fed the experimental diets for 56 days. The results revealed that: 1) the weight gain rate(WGR) in 1/3BPs, 2/3BPs, and 3/3BPs was significantly higher than that in Con(P lipids(CL) were significantly different among groups, while there was no significant difference between crude ash and phosphorus contents; 3) the levels of acid phosphatase(ACP), lysozyme(LZM), superoxide dismutase(SOD), phenol oxidase(PO) and bactericidal activity increased significantly with the inclusion of BPs; 4) in terms of water quality, no significant difference was found in p H and dissolved oxygen among diets during the whole experimental period. Moreover, even though nitrite and ammonium levels tended to increase with time, there was no significant difference among groups. The results indicated that BPs is an applicable alternative of protein source, which can substitute FM in the diets of L. vannamei; it is able to effectively promote growth performance and improve immunity. Moreover, BPs in the diets had no negative impact on water quality.

关键词： bioactive peptide fish meal litopenaeus vannamei growth performance non-specific immunity water quality

Cryo-EM structure of Mycobacterium smegmatis ribosome reveals two unidentified ribosomal proteins close to the functional centers

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Protein & Cell 2018年第4期9卷 384-388页

作者： zhifei li Xueliang Ge Yixiao Zhang Lvqin Zheng Suparna Sanyal Ning Gao State Key Laboratory of Membrane Biology Peking-Tsinghua Joint Center for Life Sciences School of Life Sciences PekingUniversity Beijing 100871 China Beijing Advanced Innovation Center for Structural Biology Tsinghua-Peking Joint Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China Department of Cell and Molecular Biology Uppsala UniversityBMC Box-596 Uppsala Sweden

Dear Editor, Mycobacterium smegmatis is commonly used as a labora- tory surrogate in studying the physiology and pathogenesis of disease-causing mycobacteria, including Mycobacterium tuberculosis, which causes tubercu...

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Structural dynamics of the yeast Shwachman- Diamond syndrome protein （Sdol） on the ribosome and its implication in the 60S subunit maturation

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Protein & Cell 2016年第3期7卷 187-200页

作者： Chengying Ma Kaige Yan Dan Tan Ningning li Yixiao Zhang Yi Yuan zhifei li Meng-Qiu Dong Jianlin Lei Ning Gao School of life Sciences Tsinghua University Beijing 100084 China National Institute of Biological Sciences Beijing 102206 China Graduate Program in Chinese Academy of Medical Sciences and Pekinq Union Medical College Beiiin.q 100730 China

The human Shwachman-Diamond syndrome （SDS） is an autosomal recessive disease caused by mutations in a highly conserved ribosome assembly factor SBDS. The functional role of SBDS is to cooperate with another assembly factor, elongation factor l-like （Eft1）, to pro- mote the release of eukaryotic initiation factor 6 （elF6） from the late-stage cytoplasmic 60S precursors. In the present work, we characterized, both biochemically and structurally, the interaction between the 60S subunit and SBDS protein （Sdolp） from yeast. Our data show that Sdolp interacts tightly with the mature 60S subunit in vitro through its domain I and II, and is capable of bridging two 60S subunits to form a stable 2：2 dimer. Structural analysis indicates that Sdolp bind to the ribosomal P-site, in the proximity of uL16 and uL5, and with direct contact to H69 and H38. The dynamic nature of Sdolp on the 60S subunit, together with its strategic binding position, suggests a surveillance role of Sdolp in monitoring the conformational maturation of the ribosomal P-site. Altogether, our data support a con- formational signal-relay cascade during late-stage 60S maturation, involving uL16, Sdolp, and Efllp, which interrogates the functional P-site to control the departure of the anti-association factor elF6.

关键词： ribosome biogenesis SBDS SDS Sdol,cryo-electron microscopy (cryo-EM)

Climate Issue and China in *** River Policy

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Peace 2014年第2期 45-47页

作者： li zhifei Chinese Academy of Social Sciences

Since taking office in 2009,the Obama administration has much-touted"pivot"to Asia policy,strengthened the *** leadership and policy coordination of the trans-Pacific order,and taken Southeast Asia the new fulcrum of its strategic operations and the Lower Mekong Region a vital flank of its new Asia-Pacific *** a Congressional Hearing

关键词： administration leadership Southeast cooperation fl

Extraction of flocculants from a strain of Bacillus thuringiensis and analysis of their properties

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Aquaculture and Fisheries 2017年第4期2卷 179-184页

作者： Jingrong Wu Guangjun Wang zhifei li Ermeng Yu Jun Xie Zonglin Zheng Pearl River Fisheries Research Institute Chinese Academy of Fishery SciencesGuangzhouGuangdong 510380China Southwest University Rongchang Campus Chongqing 402460China

In a preliminary screening study,our laboratory isolated from the biofloc in aquaculture waters a strain of Bacillus thuringiensis,which produced highly efficient *** the present study,we extracted the crude flocculants from this strain and analyzed their *** analysis indicated that the flocculants were mainly distributed in the supernatant of the fermentation *** flocculants were extracted using an ethanol extraction method,and the chemical compositions and morphology of the crude flocculants were analyzed using the Molish reaction,Fehling reaction,ninhydrin reaction,biuret reaction,phenol-sulfuric acid assay,Coomassie brilliant blue staining,ultraviolet scanning,infrared scanning and scanning electron *** carbohydrate composition of the polysaccharides in the flocculants was analyzed with thin layer *** results indicated that flocculants were solid substances with an ivory white color and their texture was loose and *** under scanning electron microscopy revealed that their ultra-morphology consisted of small,long and fiber-like *** and physical analyses indicated that polysaccharides accounted for 34.5%of the components in the crude *** monosaccharides present in crude flocculants included mainly glucose,galactose and mannitose.

关键词： Bacillus thuringiensis Bio-flocculant Property analysis Polysaccharides

Mechanisms of resistance to trastuzumab in HER2-positive gastric cancer

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Chinese Journal of Cancer Research 2024年第3期36卷 306-321页

作者： zhifei li Huan Zhao Huihui Hu Haili Shang Yongjing Ren Wenhui Qiu Hao Su Huifang Lyu Xiaobing Chen Department of Oncology the Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalHenan Engineering Research Center of Precision Therapy of Gastrointestinal CancerZhengzhou Key Laboratory for Precision Therapy of Gastrointestinal CancerZhengzhou 450008China Henan University of Traditional Chinese Medicine Zhengzhou 450046China State Key Laboratory of Esophageal Cancer Prevention&Treatment Key Laboratory of Advanced Drug Preparation TechnologiesMinistry of EducationSchool of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001China The First Affiliated Hospital of Xinxiang Medical University Xinxiang 453000China Department of Oncology the Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhou 450008China

Gastric cancer is one of the most prevalent cancers worldwide,and human epidermal growth factor receptor 2(HER2)-positive cases account for approximately 20%of the total ***,trastuzumab+chemotherapy is the recommended first-line treatment for patients with HER2-positive advanced gastric cancer,and the combination has exhibited definite efficacy in HER2-targeted ***,the emergence of drug resistance during treatment considerably reduces its effectiveness;thus,it is imperative to investigate the potential mechanisms underlying *** the present review article,we comprehensively introduce multiple mechanisms underlying resistance to trastuzumab in HER2-positive gastric cancer cases,aiming to provide insights for rectifying issues associated with resistance to trastuzumab and devising subsequent treatment strategies.

关键词： HER2 gastric cancer trastuzumab drug resistance