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An Approximation Algorithm Based on Seeding Algorithm for Fuzzy k-Means Problem with Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 387-409页

作者： wen-Zhao liu Min li School of Mathematics and Statistics Shandong Normal UniversityJinan 250014ShandongChina

As a classic NP-hard problem in machine learning and computational geometry,the k-means problem aims to partition the given dataset into k clusters according to the minimal squared Euclidean *** from k-means problem and most of its variants,fuzzy k-means problem belongs to the soft clustering problem,where each given data point has relationship to every center *** to fuzzy k-means problem,fuzzy k-means problem with penalties allows that some data points need not be clustered instead of being paid *** this paper,we propose an O(αk In k)-approximation algorithm based on seeding algorithm for fuzzy k-means problem with penalties,whereαinvolves the ratio of the maximal penalty value to the minimal ***,we implement numerical experiments to show the effectiveness of our algorithm.

关键词： Approximation algorithm Seeding algorithm Fuzzy k-means problem with penalties

Characteristics of Bi-2223 HTS Tapes Under Short-Circuit Current Impacts in Hybrid Energy Transmission Pipelines

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 736-745页

作者： Yuguang Sun Chao Yin Weizhen li Xinyang li Xiaohua jiang Department of Electric Engineering Tsinghua UniversityBeijing 100084China

A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.

关键词： Bi-2223 high-temperature superconducting(HTS)tape critical current hybrid energy transmission pipeline liquefied natural gas(LNG)cooling temperature short-circuit current impact characteristics

Experimental investigation about the incipient velocity of spherical particles on a hemispherical bed surface

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Particuology 2024年第5期88卷 49-61页

作者： Chuannan li Jie Chen Changbo jiang Xie li Zhiyuan Wu School of Hydraulic and Environmental Engineering Changsha University of Science & TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

The sediment particles play a huge role in shaping the bed load *** this research,240 water-tunnel experiments are carried out to investigate the incipient velocity of the observation particles in two particle *** accurately predict the incipient velocity of the observation particles,the equation is conceived by the rolling instability *** incipient velocity equations and experimental data are used to analyze the trend of dispersive pressure and the effect of arrangement position on *** find that it is appropriate to choose the coefficient of drag as 0.261 and the coefficient of lift as 0.198 for the incipient velocity equation of spherical particles on the hemispherical bed ***,the dispersive pressure is closely related to the flow state,particle size,and particle arrangement,which leads to the incipient velocity of the observation particle being at a minimum when the interference particle angle is 45°.Finally,the particle spacing and the projected area changed with the arrangements,directly affecting the incipient velocity of the observed *** analysis of four aspects for the coefficients,dispersive pressure,different particle spacing,and projected area will facilitate the prediction of particle incipient velocity,especially on hemispherical beds.

关键词： Hemispherical bed surface Observed particle Interference particle Dispersive pressure Incipient velocity

Surface morphologies of Mg-Gd alloy particle during its reactions with O_(2) and Teflon

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Defence Technology（防务技术） 2024年第3期33卷 209-221页

作者： Yifan li Hongtao Yang Aifeng jiang Dongming Song Yanchun li Department of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210097China Xi'an Modern Chemistry Research Institute Xi'an 710065China Southwest Technology and Engineering Research Institute Chongqing 400039China

Mg-Gd alloy particle has exhibited its unique combustion properties as the fuel of Mg/Teflon/Viton(MTV).Mg-Gd alloy/Teflon/Viton(MGTV)could burn at lower ambient pressure than *** further investigate the reaction of MGTV in air,it was investigated via thermo gravity-differential scanning calorimetry(TG-DSC).Meanwhile,the morphologies and element distributions on the alloy surface during the reaction of MGTV in air were investigated via scanning electronic microscope-mapping-electronic differential ***,a similar experimental protocol on the Mg-Gd alloy particle during oxidation was also *** results showed that owning to a protective oxide shell,the onset oxidation temperature of Mg-Gd alloy is higher than ***,the onset oxidation temperature of the exceeded Mg-Gd alloy in MGTV is significantly lower than that of the exceeded Mg in *** was due to the existence of GdOF,which could significantly lower the oxidation temperature of the exceeded ***,a possible reaction mechanism was *** fascinating oxidation properties of Mg-Gd alloy suggested its promising applications in energetic materials.

关键词： Mg-Gd alloy Energetic materials Morphology EDS GdOF

Self-propelled Leidenfrost droplets on femtosecond-laser-induced surface with periodic hydrophobicity gradient

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International Journal of Extreme Manufacturing 2024年第2期6卷 502-509页

作者： Bohong li Lan jiang Xiaowei li Zhipeng Wang Peng Yi Laser Micro/Nano Fabrication Laboratory School of Mechanical EngineeringBeijing Institute of TechnologyBeijingPeople’s Republic of China Beijing Institute of Technology Chongqing Innovation Center ChongqingPeople’s Republic of China Yangtze Delta Region Academy of Beijing Institute of Technology JiaxingPeople’s Republic of China

The controllable transfer of droplets on the surface of objects has a wide application prospect in the fields of microfluidic devices,fog collection and so *** Leidenfrost effect can be utilized to significantly reduce motion ***,the use of 3D structures limits the widespread application of self-propulsion based on Leidenfrost droplets in microelectromechanical *** manipulate Leidenfrost droplets,it is necessary to create 2D or quasi-2D *** this study,femtosecond laser is applied to fabricate a surface with periodic hydrophobicity gradient(SPHG),enabling directional self-propulsion of Leidenfrost *** field analysis within the Leidenfrost droplets reveals that the vapor layer between the droplets and the hot surface can be modulated by the SPHG,resulting in directional propulsion of the inner *** viscous force between the gas and liquid then drives the droplet to move.

关键词： self-propelled Leidenfrost droplets periodic hydrophobicity gradient femtosecond laser fabrication

Colorectal cancer’s burden attributable to a diet high in processed meat in the Belt and Road Initiative countries

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 182-196页

作者： Gu liu Chang-Min li Fei Xie Qi-Lai li liang-Yan liao wen-Jun jiang Xiao-Pan li Guan-Ming Lu Department of Gastrointestinal Surgery The First Affiliated HospitalJinan UniversityGuangzhou 510630Guangdong ProvinceChina Department of Gastrointestinal Surgery Chenzhou Third People’s HospitalChenzhou 423000Hunan ProvinceChina Department of Gastrointestinal Surgery Chenzhou First People’s Hospital and the First Affiliated Hospital of Xiangnan UniversityChenzhou423000 Hunan ProvinceChina Department of Breast and Thyroid Surgery the Affiliated Hospital of Youjiang Medical University for NationalitiesBaise 533000Guangxi Zhuang Autonomous RegionChina Department of Health Management Center Zhongshan HospitalShanghai Medical College of Fudan UniversityShanghai 200032China

BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)*** addition,these countries have a substantial consumption of processed ***,the burden and trend of CRC in relation to the consumption of a diet high in processed meat(DHPM-CRC)in these“B and R”countries remain *** To analyze the burden and trend of DHPM-CRC in the“B and R”countries from 1990 to *** We used the 2019 Global Burden of Disease Study to collate information regarding the burden of *** and age-standardized rates(ASRs)of deaths along with the disability-adjusted life years(DALYs)were determined among the“B and R”countries in 1990 and *** joinpoint regression analysis,the average annual percent change(AAPC)was used to analyze the temporal trends of age-standardized DALYs rate(ASDALR)from 1990 to 2019 and in the final decade(2010–2019).RESULTS We found geographical differences in the burden of DHPM-CRC among“B and R”countries,with the three highest-ranking countries being the Russian Federation,China,and Ukraine in 1990,and China,the Russian Federation,and Poland in *** burden of DHPM-CRC generally increased in most member countries from 1990 to 2019(all Pline was observed in Kyrgyzstan,Central Asia,with an AAPC value of-2.05%(95%CI:-2.37%to-1.73%).A substantial upward trend in ASR of mortality,years lived with disability,years of life lost,and DALYs from DHPM-CRC changes in 1990-2019 and the final de

关键词： Belt and Road Initiative countries Colorectal cancer Burden of disease Dietary risk factors Processed meat Disability-adjusted life years Trend analysis

Clinical Analysis and Mental Health Survey of Hemophilia Carriers:a Cross-sectional Study

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Current Medical Science 2024年第2期44卷 435-440页

作者： wen WANG li-juan jiang Dong-yan CUI Ai ZHANG Xiong WANG Ai-guo liU Qun HU Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Laboratory Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health *** purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of ***,we aimed to investigate the mental health status of HCs in ***:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this *** distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or *** factor activity was detected by a one-stage clotting *** Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental ***:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,*** median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding *** total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and *** pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations

关键词： hemophilia A hemophilia B mutation carrier mental health

Aerodynamic/control integrated optimization method for unpowered high-speed vehicle configuration design

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Chinese Journal of Aeronautics 2024年第7期37卷 153-167页

作者： Xin PAN linlin WANG li li Lulu jiang Gang CHEN State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Shannxi Key Laboratory for Environment and Control of Flight Vehicle School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Beijing Institute of Space Long March Vehicle Beijing 100076China AVIC Xi’an Aeronautics Computing Technique Research Institute Xi’an 710068China

The unpowered high-speed vehicle experiences a significant coupling between the disciplines of aerodynamics and control due to its characteristics of high flight speed and extensive maneuverability within large *** conventional aircraft conceptual design process follows a sequential design approach,and there is an artificial separation between the disciplines of aerodynamics and control,neglecting the coupling effects arising from their *** a result,this design process often requires extensive iterations over long periods when applied to high-speed vehicles,and may not be able to effectively achieve the desired design *** enhance the overall performance and design efficiency of high-speed vehicles,this study integrates the concept of Active Control Technology(ACT)from modern aircraft into the philosophy of aerodynamic/control integrated *** integrated optimization strategies,with differences in coupling granularity,have been ***,these strategies are put into action on a biconical vehicle that operates at Mach *** results reveal that the comprehensive performance of the synthesis optimal model derived from the aerodynamic/control integrated optimization strategy is improved by 31.76%and 28.29%respectively compared to the base model under high-speed conditions,demonstrating the feasibility and effectiveness of the method and optimization strategies ***,in comparison to the single-stage strategy,the multi-stage strategy takes into deeper consideration the impact of control *** a result,the control performance of the synthesis opti-mal model derived from the multi-stage strategy improves by 13.99%,whereas the single-stage strategy only achieves a 5.79%*** method enables a fruitful interaction between aerodynamic configuration design and control system design,leading to enhanced overall performance and design ***,it improves the controllability of high-sp

关键词： Aerodynamic/Control Integrated Optimization MDO High-speed vehicle Shape Optimization Controllability

Network pharmacology-based exploration of molecular mechanisms underlying therapeutic effects of Jianpi Huatan Quyu recipe on chronic heart failure with spleen Qi deficiency syndrome

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World Journal of Cardiology 2024年第7期16卷 422-435页

作者： Si-Qi li Dong-Yu Min Jun-wen jiang Xiao-Ying li Xu-Na Yang wen-Bo Gu Jia-Hui jiang li-Hao Chen Han Nan Ze-Yu Chen Second Department of Cardiology The Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110000Liaoning ProvinceChina

BACKGROUND Chronic heart failure is a complex clinical *** Chinese herbal compound preparation Jianpi Huatan Quyu recipe has been used to treat chronic heart failure;however,the underlying molecular mechanism is still not *** To identify the effective active ingredients of Jianpi Huatan Quyu recipe and explore its molecular mechanism in the treatment of chronic heart *** The effective active ingredients of eight herbs composing Jianpi Huatan Quyu recipe were identified using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis *** target genes of chronic heart failure were searched in the Genecards *** target proteins of active ingredients were mapped to chronic heart failure target genes to obtain the common drugdisease targets,which were then used to construct a key chemical componenttarget network using Cytoscape 3.7.2 *** protein-protein interaction network was constructed using the String *** Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed through the Metascape ***,our previously published relevant articles were searched to verify the results obtained via network *** A total of 227 effective active ingredients for Jianpi Huatan Quyu recipe were identified,of which quercetin,kaempferol,7-methoxy-2-methyl isoflavone,formononetin,and isorhamnetin may be key active ingredients and involved in the therapeutic effects of TCM by acting on STAT3,MAPK3,AKT1,JUN,MAPK1,TP53,TNF,HSP90AA1,p65,MAPK8,MAPK14,IL6,EGFR,EDN1,FOS,and other *** pathways identified by KEGG enrichment analysis include pathways in cancer,IL-17 signaling pathway,PI3K-Akt signaling pathway,HIF-1 signaling pathway,calcium signaling pathway,cAMP signaling pathway,NF-kappaB signaling pathway,AMPK signaling pathway,*** studies on Jianpi Huatan Quyu recipe suggested that this Chinese compound preparation can regulate the TNF-α,IL-6,MAPK

关键词： Jianpi Huatan Quyu recipe Traditional Chinese medicine Chronic heart failure Data mining Network pharmacology Bioinformatics Spleen Qi deficiency syndrome