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THREE DIMENSIONAL MODELING AND DYNAMIC ANALYSIS OF FOUR—WHEEL—STEERING VEHICLES

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Acta Mechanica Sinica 2003年第1期19卷 79-88页

作者：胡海岩韩强 InstituteofVibrationEngineeringResearch NanjinguniversityofAeronauticsandAstronauticsNanjing210016China DepartmentofMechanics SouthChinaUniversityofScienceandTechnologyGuangzhou510641china

The paper presents a nonlinear dynamic model of 9 degrees of freedom for four-wheelsteering vehicles. Compared with those in previous studies, this model includes the pitch and roll of the vehicle body, the motion of 4 wheels in the accelerating or braking process, the nonlinear coupling of vehicle body and unsprung part, as well as the air drag and wind effect. As a result, the model can be used for the analysis of various maneuvers of the four-wheel-steering vehicles. In addition, the previous models can be considered as a special case of this model. The paper gives some case studies for the dynamic performance of a four-wheel-steering vehicle under step input and saw-tooth input of steering angle applied on the front wheels, respectively.

关键词： vehicle dynamics nonlinear dynamics modeling control

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高聚焦性双梯形双层经颅磁线圈的设计

郑州大学学报（工学版） 2025年第1期46卷 119-125页

作者：靳贵平杨思思涂治红徐向民邢晓芬华南理工大学电子与信息学院广东广州510641

基于聚焦性能对经颅磁线圈的影响,针对聚焦型线圈商用不足的问题,设计一种具有高聚焦性的单通道双梯形双层线圈。首先使用球头模型分析不同尺寸、相同结构的线圈性能,得到较优的线圈尺寸;为进一步提升聚焦度,再以中尺寸线圈为研究目标,... 详细信息

基于聚焦性能对经颅磁线圈的影响,针对聚焦型线圈商用不足的问题,设计一种具有高聚焦性的单通道双梯形双层线圈。首先使用球头模型分析不同尺寸、相同结构的线圈性能,得到较优的线圈尺寸;为进一步提升聚焦度,再以中尺寸线圈为研究目标,探讨五种不同结构的双层线圈与两种商用8字形线圈的性能差异,得到最优线圈的结构;最后使用50组存在个体差异性的真实脑模型进行仿真验证,分析球头模型结果的可靠性。仿真结果表明:使用球头模型时,优化后的新型线圈对比70 mm figure-8 coil的聚焦度提升了69.48%,刺激深度减少了27.18%;对比25 mm figure-8 coil的聚焦度提升了44.78%,刺激深度减少了8.5%;使用50组真实脑模型时,优化后的新型线圈对比70 mm figure-8 coil的聚焦度提升了62.07%,刺激深度减少了25.71%;对比25 mm figure-8 coil的聚焦度提升了39.49%,刺激深度减少了9.5%。两种模型仿真数据结果趋于一致,证实了仿真可靠性的同时也证明了新型线圈具有更强的刺激强度和聚焦度,能大大提升TMS治疗的安全性,减少不适感,同时单通道设计易于实现,具有较高的性能优势。

关键词：电磁感应聚焦度经颅磁刺激 Sim4Life 真实脑模型

CONDITIONED SUPERPROCESSES

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Chinese Annals of Mathematics,Series B 1997年第2期18卷 249-256页

作者： LICUNHANG WURONG CollegeofBusinessandAdministration SouthChinaUniversityofTechnologyGuangzhou510641 DepartmentofMatbematics NankaiUniversityTianjin300071

A class of superprocesses which dies out is *** the condition of norextinction, a new superprocess is constructed,its life time is infinite, and its distribution is determined by the moment function. Several limit the... 详细信息

关键词： Superprocess Extinction time Occupation time process

Theoretical Calculations on the Second-order Nonlinear Optical Property of Chiral Bis-corroles

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Chinese Journal of Structural Chemistry 2007年第8期26卷 955-961页

作者： YING Xiao DENG Qin LIAO Shi-Jun HU Xi-Ming LIU Hai-Yang CHANG Chi-Kwong Department of Applied Physics South China University of Technology Guangzhou 510641 China Department of Applied Chemistry South China University of Technology Guangzhou 510641 China Department of Chemistry The Hongkong University of Science and Technology Hongkong China

The second-order nonlinear optical （NLO） properties of 5,10,15-triphenylcorrole （TPC）, 5,10,15,20-tetraphenylporphyrin （TPP） and L-amino acid bridged bis-corroles 1,2,3 and 4 have been calculated by using TDHF/PM3 method based on the RHF/6-31G （TPC and TPP） or semiempirical PM3 （1, 2, 3, 4） optimized geometries. Calculation results showed TPC and TPP have C1 and D2h symmetry, respectively when N-H protons are localized on the nitrogen atoms. TPC is the second-order NLO active chromophore due to the cancellation of centrosymmetrical structure and its first hyperpolarizability β increases to 11.524×10^-30 esu. Under electrical dipole approximation, βvalues of bis-corroles 1, 2, 3 and 4 vary from 9.831×10^-30 to 14.221×10^-30 esu, and no much improvement in the first hyperpolarizability was observed as compared to TPC ***, β values of bis-corroles 1, 2, 3 and 4 are improved by about 4 times as compared to their bis-porphyrin counterparts. The analysis of β components indicates that β of this kind of bis-corroles is mainly contributed from its radial component βr. With the variation of amino acid side chains, βHRS, β,βxyz, βr and βa of bis-corroles change remarkably. Chiral L-amino acid bridged bis-corroles 2, 3 and 4 have a right-handed helix structure, and their chiral component βxyz matches βxyz ∝ r^2 ζ/L^4 （helix parameters）, showing the second-order chiral NLO response of these bis-corroles could be described by one-electron helical model theory. It was found that the radial component βr of chiral helix bis-corroles also matches βr ∝ r^2 ζ/L^4.

关键词： corrole amino acid chiral bis-corrole the second-order NLO TDHF/PM3

Thermal reversible gelation during phase separation of poly(N-isopropyl acrylamide)/water solution

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Science China Chemistry 2000年第4期43卷 428-434页

作者：曾钫刘新星童真杨燕银吴水珠 Institute of Materials Science South China University of Technology Guangzhou 510641 China

By dynamic viscoelastic measurement for PNIPAM/water solution it has been found that below the phase separation temperature (about 32°C), the system is homogeneous fluid; while upon being heated to about 32°C, the solution undergoes phase separation and the storage modulus G’ increases sharply and exceeds the loss modulus G”, indicating the physical network formation during the phase separation. Based on the percolation model, the gel points Tgel were obtained by applying the dynamic scaling theory (DST) and Winter’s criterion. The critical exponent n was also obtained to be 0.79 through DST, which is different from 0.67, the critical point of chemically crosslinked network predicted through DST. The obtained n value reflects the special property of physical network being different from chemical network.

关键词： poly(N-isopropyl acrylamide) physical crosslink network thermal reversible gel.

Application　of　Exergoeconomics　to　the　Analysis　and　Optimization　of　Process　Systems

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Journal of Thermal Science 1996年第1期5卷 1-10页

作者： QinglinChen BenHua ChemicalEngineeringResearchInstitute SouthChinaUniversityofTechnology（Guangzhou510641 ChemicalEnginee

The definitions and purposes of energy systems and process systems are compared in this paper by considering the role of energy in systems with emphasis on the differences in the methods used to optimize the exergoeconomic benefits of both types of *** process system exergoeconomic relationship primarily include the establishment of the Three-link model of process systems,the composition of objective functions,and the corresponding boundary constraint conditions for *** Three-Kink-Method(TLM) which is based on exergoeconomics,can be used to effectively optimize process *** TLM used to optimize process systems is outlined in this Some aspects which need further development are also identified.

关键词： exergoeconomics process systems.

Hyperon Dynamics in Heavy-Ion Collisions near Threshold Energy

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Chinese Physics Letters 2021年第9期38卷 33-37页

作者： Ding-Chang Zhang Hui-Gan Cheng Zhao-Qing Feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510641China

Within the framework of quantum molecular dynamics transport model,the isospin and in-medium effects on the hyperon production in the reaction of ^(197)Au+^(197) Au are investigated thoroughly.A repulsive hyperon-nucleon potential from the chiral effective field theory is implemented into the model,which is related to the hyperon momentum and baryon *** correction on threshold energy of the elementary hyperon cross section is taken into *** is found that the𝛴yields are suppressed in the domain of midrapidity and kinetic energy spectra with the *** hyperons are emitted in the reaction plane because of the strangeness exchange reaction and reabsorption process in the nuclear ***∑^(−)/𝛴∑^(+)ratio depends on the stiffness of nuclear symmetry energy,in particular in the high-energy region(above 500 MeV).

关键词： potential density elementary

Constraint on nuclear symmetry energy imposed by f-mode oscillation of neutron stars

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Communications in Theoretical Physics 2021年第11期73卷 122-130页

作者： Jing Zhang Dehua Wen Yuxi Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China

Due to improvements in the sensitivity of gravitational wave(GW)detectors,the detection of GWs originating from the fundamental quasi-normal mode(f-mode)of neutron stars has become *** future detection of GWs originating from the f-mode of neutron stars will provide a potential way to improve our understanding of the nature of nuclear matter inside neutron *** this work,we investigate the constraint imposed by the f-mode oscillation of neutron stars on the symmetry energy of nuclear matter using Bayesian analysis and parametric *** is shown that if the frequency of the f-mode of a neutron star of known mass is observed precisely,the symmetry energy at twice the saturation density(E_(sym)(2_(ρ0)))of nuclear matter can be constrained within a relatively narrow *** example,when all the following parameters are within the given intervals:220≤K0≤260 Me V,28≤E_(sym)(ρ0)≤36 Me V,30≤L≤90 Me V,-800≤J0≤400 Me V,-400≤K_(sym)≤100 Me V,-200≤Jsym≤800 Me V,E_(sym)(2ρ0)will be constrained to within-+48.***.56.6 Me V if the f-mode frequency of a canonical neutron star(1.4 M■)is observed to be 1.720 k Hz with a 1%relative ***,if only f-mode frequency detection is available,*** is no stellar mass measurement,a precisely detected f-mode frequency can also impose an accurate constraint on the symmetry *** example,given the same parameter space and the same assumed observed f-mode frequency mentioned above,and assuming that the stellar mass is in the range of 1.2–2.0 Me,E_(sym)(2ρ0)will be constrained to within 49.5■*** addition,it is shown that a higher slope of 69≤L≤143 Me V will give a higher posterior distribution of E_(sym)(2ρ0),53.8■MeV.

关键词： f-mode Bayesian analysis nuclear symmetry energy neutron star

婴儿肠道源长双歧杆菌B2-01的益生特性及其高密度培养

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食品科学 2025年第1期46卷 28-39页

作者：彭芸燕钟舒莹刘冬梅许喜林华南理工大学食品科学与工程学院广东广州510641

以广州市3月龄健康婴儿粪便中分离出的乳酸杆菌为研究对象,经分子生物学鉴定确认为长双歧杆菌(Bifidobacterium longum),命名为B2-01。对B2-01进行包括体外抗氧化活性和肝损伤保护活性在内的益生特性和高密度培养研究,结果表明:B2-01具... 详细信息

以广州市3月龄健康婴儿粪便中分离出的乳酸杆菌为研究对象,经分子生物学鉴定确认为长双歧杆菌(Bifidobacterium longum),命名为B2-01。对B2-01进行包括体外抗氧化活性和肝损伤保护活性在内的益生特性和高密度培养研究,结果表明:B2-01具有较强的1,1-二苯基-2-三硝基苯肼自由基、羟自由基、超氧阴离子自由基、2,2′-联氮-双-(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力和抗脂质过氧化能力;在最高作用水平(DMEM完全培养基中发酵上清液体积分数10%)下,过氧化氢损伤和乙醇损伤L02细胞存活率可分别提高至89.10%和91.38%,同时能显著降低肝细胞中转氨酶的活力;高密度培养研究优化后的最佳培养条件确定为酵母浸提粉添加量3.45%、葡萄糖2.48%、乳糖2.79%、细菌学蛋白胨3.00%、低聚半乳糖2.50%。在此优化条件下,发酵液的活菌数最高可达4.20×10^(9) CFU/m L,比优化前(7.71×10^(8) CFU/mL)提高5.45倍。

关键词：长双歧杆菌婴儿肠道抗氧化活性酒精肝保护高密度培养