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A New Classification Framework,Theoretical Interpretation and Application of Curvilinear Relationships

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Frontiers of Business Research in China 2022年第1期16卷 1-22页

作者： LI Hai ZHU jinqiang Business School Beijing Normal UniversityBeijing 100875China School of Management Minzu University of ChinaBeijing 100081China

In many study fields,scholars have extensively explored the linear relationships between *** some recent studies have shown that the linear models sometimes fail to reflect true relationships between variables and often misguide ***,scholars strongly advocate exploring the curvilinear relationships between *** on previous studies and the principles of mathematical statistics,this paper combines the linear relationship and the curvilinear relationship and divides the curvilinear relationship into four categories according to the quadratic coefficient of the quadratic curve and the coefficient of the linear ***,according to their characteristics in the economic and management practice,this study names these four types of curvilinear relationships as Gradually Getting Better effect,Too Much of a Good Thing effect,A Little Bad Thing effect or Catfish effect,and Prolonged Illness Makes the Patient a Good Doctor effect,*** these four types of curvilinear effects are discussed from four aspects in this paper:data analysis methods,theoretical connotation,application examples and theoretical ***,the application of these curvilinear effects in future research is outlooked.

关键词： Curvilinear effects Gradually Getting Better effect Too Much of a Good Thing effect Catfish effect Prolonged Illness Makes the Patient a Good Doctor effect

Swarm intelligence for classification of remote sensing data

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Science China Earth Sciences 2008年第1期51卷 79-87页

作者： Liu XiaoPing Li Xia Peng XiaoJuan Li HaiBo He jinqiang School of Geography and Planning Sun Yat-sen University Guangzhou 510275 China South China Sea Environment Monitor Center Guangzhou 510300 China

This paper proposes a new method to classify remote sensing data by using Particle Swarm Optimization (PSO). This method is to generate classification rules through simulating the behaviors of bird flocking. Optimized... 详细信息

关键词： swarm intelligence particle swarm optimization (PSO) remote sensing

Active Control of Thermo-mechanical Buckling of Composite Laminated Plates Using Piezoelectric Actuators

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Acta Mechanica Solida Sinica 2021年第3期34卷 369-380页

作者： Yao Zhang Yu Xue Wei Yuan Wensheng Ma jinqiang Li Fengming Li College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China Key Laboratory of Aero-engine Vibration Technique AECC Hunan Aviation Power Plant Research InstituteZhuzhou12000China

This paper is concerned with the active control of thermomechanical buckling of composite laminated plates using piezoelectric facesheets as *** four-variable trigonometric shear deformation theory and Hamilto's principle are applied to formulate the governing equation of structural *** temperature feedback control strategy is proposed to conduct the active control of thermal-mechanical *** simulation results show that the thermo-mechanical buckling of composite laminated plates can be effectively controlled by the presented control *** a specific control gain,the critical mechanical buckling load can remain constant at different *** effects of geometric parameters,fiber angle,stacking sequence,position of piezoelectric layer and boundary conditions on the active control of thermo-mechanical buckling are also investigated.

关键词： Buckling control Thermo-mechanical buckling Laminated plate Piezoelectric actuator Temperature feedback

Mg/Ca,Ba/Ca,and S/Ca ratios as environmental and growth proxies for bivalve shells from the Haima cold seep,South China Sea

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Journal of Oceanology and Limnology 2023年第2期41卷 660-672页

作者： Jingya CAO Shengxiong YANG Danling tanG Junxi FENG jinqiang LIANG Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Department of Ocean Science Hong Kong University of Science&TechnologyHong Kong 999077China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyChina Geological SurveyMinistry of Natural ResourcesGuangzhou 511458China

Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 *** on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,*** addition,the profile can be subdivided into two parts:altered and unaltered *** inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain ***-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of *** with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the ***,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.

关键词： Mg/Ca,Ba/Ca,and S/Ca ratios laser inductively coupled plasma mass spectrometry(LA-ICPMS) Gigantidas platifrons Haima cold seep South China Sea

Synthesis and luminescence of single crystalline Bi_2O_3 nanosheets

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Science China(Technological Sciences) 2011年第1期54卷 19-22页

作者： FANG GuoLi CHEN Guang WANG Xiong LIU jinqiang Engineering Research Center of Materials Behavior and Design Ministry of Education Joint Laboratory ofNanostructured Materials and Technology Nanjing University of Science and Technology Nanjing 210094 China

Single crystalline Bi2O3 nanosheets have been synthesized by the surfactant assisted solvothermal method, using oleic acid and sodium dodecyl benzene sulfonate （SDBS） as compound surfactants. The thickness of Bi2O3 nanosheets is 40--70 nm with a monoclinic crystal structure. High-resolution transmission electron microscopy observation reveals that （ 345 ） lattice plane of the single crystal is parallel to the surface of the nanosheets. The cooperative effect of oleic acid encapsulated SDBS is the key to form single crystalline a-Bi2O3 nanosheets with a preferred growth orientation. An obvious blue shift of the single crystalline Bi2O3 nanosheets with a preferred surface （ 34-5 ） is observed due to quantum confinement effects in thickness and optical anisotropy.

关键词： α-Bi2O3 nanosheets surfactant assisted solvothermal luminescence property

Bandgaps and vibration isolation of local resonance sandwich-like plate with simply supported overhanging beam

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1555-1570页

作者： Chenxu QIANG Yuxin HAO Wei ZHANG jinqiang LI Shaowu YANG Yuteng CAO College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

The concept of local resonance phononic crystals proposed in recent years provides a new chance for theoretical and technical breakthroughs in the structural vibration *** this paper,a novel sandwich-like plate model with local resonator to acquire specific low-frequency bandgaps is *** core layer of the present local resonator is composed by the simply supported overhanging beam,linear spring and mass block,and well connected with the upper and lower surface *** simply supported overhanging beam is free at right end,and an additional linear spring is added at the left *** wave equation is established based on the Hamilton principle,and the bending wave bandgap is further *** theoretical results are verified by the COMSOL finite element *** bandgaps and vibration characteristics of the local resonance sandwich-like plate are studied in *** factors which could have effects on the bandgap characteristics,such as the structural damping,mass of vibrator,position of vibrator,bending stiffness of the beam,and the boundary conditions of the sandwich-like plates,are *** result shows that the stopband is determined by the natural frequency of the resonator,the mass ratio of the resonator,and the surface *** shows that the width of bandgap is greatly affected by the damping ratio of the ***,it can also be found that the boundary conditions can affect the isolation efficiency.

关键词： local resonance sandwich-like plate elastic wave bandgap vibration isolation

Experimental study on out-of-plane seismic performance of precast composite sidewalls of utility tunnel with grouting-sleeve joints

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Underground Space 2024年第3期16卷 1-17页

作者： Zilan Zhong Guangfan Li jinqiang Li Jiaxu Shen Mi Zhao Xiuli Du Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China

The precast composite reinforced concrete wall with the advantages of fewer joints,superior impermeability and rapid construction provides an efficient and environmental friendly alternative in the construction of underground utility tunnels in the last few *** investigate the seismic performance of precast concrete composite walls of utility tunnels with grouting-sleeve connection under out-ofplane loads,a series of quasi-static cyclic tests were performed on the full-scale sidewall specimens with different axial compression ratios in this *** experimental results including the failure modes,crack distributions,and the influence of different connections on the out-of-plane seismic performance of precast concrete composite wall were carefully examined and compared with those from the cyclic tests of the cast-in-place sidewalls of the utility *** test results show that the seismic performance of the precast concrete composite sidewall specimen,such as the hysteresis curves,the ultimate bearing capacity,stiffness degradation pattern and the ductility ratio,is basically the same as that of the cast-in-place specimen,indicating that the seismic performance of the prefabricated structure is equivalent to that of the cast-in-place ***,the grouting-sleeves of the joints can effectively transfer the reinforcement stress until the failure of the precast concrete composite sidewall specimens,which exhibits excellent out-of-plane ductility and serviceability.

关键词： Precast concrete composite walls Cyclic response Seismic performance Grouting sleeve Failure mechanism

低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响

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渔业科学进展 2025年第1期46卷 82-92页

作者：马九菊黄进强李永娟吴深基赵璐曾粤甘肃农业大学动物科学技术学院甘肃兰州730070

虹鳟(Oncorhynchus mykiss)是一种低氧敏感性鱼类,低氧胁迫下其生长、行为、代谢和免疫等均会受到影响。为了解低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响,本研究用酶活性测定和实时荧光定量PCR(RT-qPCR)方法,分析中度低氧[(... 详细信息

虹鳟(Oncorhynchus mykiss)是一种低氧敏感性鱼类,低氧胁迫下其生长、行为、代谢和免疫等均会受到影响。为了解低氧胁迫对虹鳟心脏生化指标和低氧相关基因表达的影响,本研究用酶活性测定和实时荧光定量PCR(RT-qPCR)方法,分析中度低氧[(4.5±0.1)mg/L]和重度低氧[(3.0±0.1)mg/L]胁迫4、8、12、24 h、中度低氧1个月(TMM)、重度低氧1个月(TMS)及复氧[(8.5±0.1)mg/L]12 h和24 h后虹鳟心脏中生化指标变化以及低氧相关基因的表达情况。结果显示,在中度低氧胁迫下,虹鳟心脏中丙酮酸激酶(PK)、总胆固醇(TC)、乳酸(LD)和谷丙转氨酶(GPT)水平在8 h时升高,24 h时降低,复氧后仍显著高于对照水平(P0.05)。三磷酸腺苷酶(ATPase)、脂肪酶(LPS)、TC、谷草转氨酶(GOT)和GPT水平在12 h时降低,复氧后均恢复至正常水平(P>0.05)。与对照组相比,TMM组和TMS组中PK、TC、乳酸脱氢酶(LDH)和GPT水平均显著升高(P0.05),重度低氧胁迫下pk、sdh和vhl基因表达量显著升高(P<0.05)。本研究结果表明,低氧胁迫使虹鳟心脏发生代谢紊乱,影响体内正常的代谢水平,并对虹鳟心脏造成一定损伤。本研究可为进一步阐明虹鳟低氧胁迫的调控机制提供基础资料。

关键词：虹鳟低氧胁迫生化指标代谢基因表达

Dynamic and Thermodynamic Features of Low and Middle Clouds Derived from Atmospheric Radiation Measurement Program Mobile Facility Radiosonde Data at Shouxian, China

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Advances in Atmospheric Sciences 2016年第1期33卷 21-33页

作者： jinqiang ZHANG Hongbin CHEN Xiang'ao XIA Wei-Chyung WANG Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Atmospheric Sciences Research Center University at AlbanyState University of New York

By using the radiosonde measurements collected at Shouxian,China,we examined the dynamics and thermodynamics of single- and two-layer clouds formed at low and middle *** analyses indicated that the horizontal wind speed above the cloud layers was higher than those within and below cloud *** maximum balloon ascent speed（5.3 m s^-1） was located in the vicinity of the layer with the maximum cloud occurrence frequency（24.4%）,indicating an upward motion（0.1-0.16 ms^-1）.The average thickness,magnitude and gradient of the temperature inversion layer above single-layer clouds were117±94 m,1.3±1.3℃ and 1.4±1.5℃（100 m）^-1,*** average temperature inversion magnitude was the same（1.3℃） for single-low and single-middle clouds;however,a larger gradient[1.7±1.8℃（100 m）^-1]and smaller thickness（94±67 m） were detected above single-low clouds relative to those above single-middle clouds[0.9±0.7℃（100 m）^-1 and157±120 m].For the two-layer cloud,the temperature inversion parameters were 106±59 m,1.0±0.9℃ and 1.0±1.0℃（100 m）^-1 above the upper-layer cloud and 82 ± 60 m,0.6±0.9℃ and 0.7±0.6℃（100 m）^-1 above the low-layer *** differences between the cloud-base height（cloud-top height） and the lifting condensation level（equilibrium level）were less than 0.5 km for 66.4%（36.8%） of the cases analyzed in summer.

关键词： radiosonde cloud dynamics thermodynamics