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Dynamical analysis and performance evaluation of a biped robot under multi-source random disturbances

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Acta Mechanica Sinica 2014年第6期30卷 983-994页

作者： chun-Biao Gan chang-Tao Ding Shi-Xi yang The State Key Laboratory of Fluid Power Transmission and control Department of Mechanical EngineeringZhejiang University

During bipedal walking,it is critical to detect and adjust the robot postures by feedback control to maintain its normal state amidst multi-source random disturbances arising from some unavoidable uncertain *** radical basis function（RBF）neural network model of a five-link biped robot is established,and two certain disturbances and a randomly uncertain disturbance are then mixed with the optimal torques in the network model to study the performance of the biped robot by several evaluation indices and a specific Poincar′e *** contrast with the simulations,the response varies as desired under optimal inputting while the output is fluctuating in the situation of disturbance *** results from noise inputting also show that the dynamics of the robot is less sensitive to the disturbance of knee joint input of the swing leg than those of the other three joints,the response errors of the biped will be increasing with higher disturbance levels,and especially there are larger output fluctuations in the knee and hip joints of the swing leg.

关键词： Biped robot Multi-source random disturbances Sensitive parameters RBF neural network Taguchi method Performance evaluation

Dynamics of Defect Motion in Nematic Liquid crystal Flow: Modeling and Numerical Simulation

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communications in computational Physics 2007年第6期2卷 1184-1198页

作者： chun Liu Jie Shen Xiaofeng yang Department of Mathematics Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Mathematics Purdue UniversityWest LafayetteIN 47907USA.

The annihilation of a hedgehog-antihedgehog pair in hydrodynamics of(elastically isotropic)nematic liquid crystal materials is modeled using the Erickson-Leslie theory which results in a nonlinear system for the flow velocity field and liquid crystal director field coupled through the transport of the directional order parameter and the induced elastic *** efficient and accurate numerical scheme is presented and implemented for this coupled nonlinear system in an axi-symmetric *** simulations of annihilation of a hedgehog-antihedgehog pair with different types of transport are *** particular,it is shown that the stretching parameter in the transport equation contributes to the symmetry breaking of the pair’s moving speed during the dynamics of annihilation.

关键词： Hedgehog-antihedgehog liquid crystal Navier-Stokes spectral-Galerkin method defect motion.

Adsorption of Ag on M-doped graphene:First principle calculations

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 487-494页

作者： Min Hu Zhou Fan Jian-yi Liu Kun Zhang yang Wang chun-feng yang School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Oil and Gas Reservoir Geology and Development engineering Southwest Petroleum UniversityChengdu 610500China Journal center Southwest Petroleum UniversityChengdu 610500China

Graphene is an ideal reinforcing phase for a high-performance composite filler,which is of great theoretical and practical significance for improving the wettability and reliability of the ***,the poor adsorption characteristics between graphene and the silver base filler significantly affect the application of graphene filler in the brazing *** is a great challenge to improve the adsorption characteristics between a graphene and silver base *** solve this issue,the adsorption characteristic between graphene and silver was studied with first principle *** effects of Ga,Mo,and W on the adsorption properties of graphene were *** are three possible adsorbed sites,the hollow site(H),the bridge site(B),and the top site(T).Based on this research,the top site is the most preferentially adsorbed site for Ag atoms,and there is a strong interaction between graphene and Ag *** element doping enhances local hybridization between c or metal atoms and ***,compared with other doped structures(Ga and Mo),W atom doping is the most stable adsorption structure and can also improve effective adsorption characteristic performance between graphene and Ag.

关键词： graphene filler first principle calculations adsorption characteristic

Enhanced therapeutic effects for human pancreatic cancer by application K-ras and IGF-IR antisense oligodeoxynucleotides

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World Journal of Gastroenterology 2008年第33期14卷 5176-5185页

作者： Yong-Mei Shen Xiao-chun yang chen yang Jun-Kang Shen Radioimmunoassay center & clinical Laboratory the Second Affiliated Hospital of Soochow University Suzhou 215004 Jiangsu Province China Department of MRI the Second Affiliated Hospital of Soochow University Suzhou 215004 Jiangsu Province China Radioimmunoassay center the Municipal Hospital of Suzhou Suzhou 215002 Jiangsu Province China

AIM: To investigate the combined effects of K-ras antisense oligodeoxynucleotide (K-ras ASODN) specif ic to GTT point mutation at codon 12 and type Ⅰ insulin-like growth factor receptor (IGF-IR) antisense oligodeoxynucleotide (IGF-IR ASODN) on proliferation and apoptosis of human pancreatic cancer Patu8988 cells in vitro and in vivo. METHODS: K-ras gene point mutation and its style at codon 12 of human pancreatic cancer cell line Patu8988 were detected by using polymerase chain reaction with special sequence primers (PcR-SSP) and sequence analysis. According to the mutation style, K-ras mutation ASODN specifi c to K-ras point mutation at codon 12 was designed and composed. After K-ras ASODN and IGF-IR ASODN treated on Patu8988 cells respectively or cooperatively, the proliferation and morphological change of Patu8988 cells were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony forming assay andtransmission electron microscopy; the expression of K-ras and IGF-IR mRNA and protein in the treated cells was measured by reverse-transcript polymerase chain reaction (RT-PcR) and flow cytometry respectively; apoptosis was determined by flow cytometry. The combined antitumor activity of K-ras ASODN and IGF-IR ASODN was evaluated in BALB/c nude mice bearing human pancreatic cancer inoculated with Patu8988 cells. RESULTS: The results of PcR-SSP and sequence analysis showed that the human pancreatic cancer cell line Patu8988 had point mutation at codon 12, and the mutation style was GGT→GTT. 2-32 μg/mL K-ras ASODN and 2-32 μg/mL IGF-IR ASODN could inhibit Patu8988 cells' growth, induce apoptosis and decrease the expression of K-ras and IGF-IR mRNA and protein alone. However, there was much more effective inhibition of growth and induction of apoptosis by their combination than by each one alone. In tumor bearing mice, the combination of K-ras ASODN and IGF-IR ASODN showed a signif icant inhibitory effect on the growth of transplanted pa

关键词： Pancreatic cancer Antisense oligodeoxy-nucleotide K-ras Type I insulin-like growth factor receptor Patu8988

ccA2 secure biometric identity based encryption with constant-size ciphertext

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Journal of Zhejiang University-Science c(computers and Electronics) 2011年第10期12卷 819-827页

作者： yang yang Yu-pu HU Le-you ZHANG chun-hui SUN Department of communication engineering Xidian University Xi'an 710071 China Department of Mathematics and computer Science Fuzhou University Fuzhou 350002 China Department of Mathematics Science Xidian University Xi'an 710071 China

We propose a new biometric identity based encryption scheme （Bio-IBE）, in which user biometric information is used to generate the public key with a fuzzy extractor. This is the first Bio-IBE scheme that achieves constant size ciphertext. This is also a scheme that is secure against the adaptive chosen ciphertext attack （ccA2）. Details are presented along with a discussion of Shamir＇s threshold secret sharing and fuzzy extraction of biometrics, which is based on error correction codes. We also define a security model and prove that the security of the proposed scheme is reduced to the decisional bilinear Diffie-Hellman proposed scheme has better efficiency and stronger security （DBDH） assumption. The comparison shows that the compared with the available Bio-IBE schemes.

关键词： Public key cryptography Identity-based Data security Biometric Encryption

Theoretical Investigations of the catalytic Role of Water in Propene Epoxidation on Gold Nanoclusters： A Hydroperoxyl- Mediated Pathway

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Nano Research 2011年第1期4卷 131-142页

作者： chun-Ran chang yang-Gang Wang Jun Li Department of chemistry and Key Laboratory of Organic Optoelectronics and Molecular engineering of Ministry of Education TsinghuaUniversity Beijing 100084 China

We report a comprehensive theoretical investigation of the catalytic reaction mechanisms of propene epoxidation on gold nanoclusters using density functional theory （DFT）. We have shown that water acts as a catalytic promoter for propene epoxidation on gold catalysts. Even without reducible supports, hydroperoxyl （OOH） and hydroxyl （OH） radicals are readily formed on small-size gold clusters from co-adsorbed H20 and 02, with energy barriers as low as 4-6 kcal/mol （1 cal = 4.186 J）. Propene epoxidation occurs easily through reactions between c3H6 and the weakened O-O bond of the OOH radicals on the surfaces of gold clusters.

关键词： Gold nanocluster propene epoxidation hydroperoxyl radical density functional theory

Mismatched feature detection with finer granularity for emotional speaker recognition

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Journal of Zhejiang University-Science c(computers and Electronics) 2014年第10期15卷 903-916页

作者： Li cHEN Ying-chun yang Zhao-hui WU college of computer Science & Technology Zhejiang University

The shapes of speakers' vocal organs change under their different emotional states, which leads to the deviation of the emotional acoustic space of short-time features from the neutral acoustic space and thereby the degradation of the speaker recognition performance. Features deviating greatly from the neutral acoustic space are considered as mismatched features, and they negatively affect speaker recognition systems. Emotion variation produces different feature deformations for different phonemes, so it is reasonable to build a finer model to detect mismatched features under each phoneme. However, given the difficulty of phoneme recognition, three sorts of acoustic class recognition—phoneme classes, Gaussian mixture model(GMM) tokenizer, and probabilistic GMM tokenizer—are proposed to replace phoneme recognition. We propose feature pruning and feature regulation methods to process the mismatched features to improve speaker recognition performance. As for the feature regulation method, a strategy of maximizing the between-class distance and minimizing the within-class distance is adopted to train the transformation matrix to regulate the mismatched features. Experiments conducted on the Mandarin affective speech corpus(MASc) show that our feature pruning and feature regulation methods increase the identification rate(IR) by 3.64% and 6.77%, compared with the baseline GMM-UBM(universal background model) algorithm. Also, corresponding IR increases of 2.09% and 3.32% can be obtained with our methods when applied to the state-of-the-art algorithm i-vector.

关键词： Emotional speaker recognition Mismatched feature detection Feature regulation

Analysis and optimization of thermal management system for cylindrical power battery based on distributed liquid cooling plates

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Science china Technological Sciences 2024年第12期67卷 3695-3706页

作者： ZHAO yang ZHANG Tao WANG chun TANG YinBo XI Huan National Innovation Platform (center) for Industry-Education Integration of Energy Storage Technology Xi'an Jiaotong University Key Laboratory of Thermo-Fluid Science and engineering of Ministry of Education School of Energy and Power Engineering Xi'an Jiaotong University School of Future Technology Xi'an Jiaotong University Ningbo Deye Energy Storage Technology co. Ltd.

To ensure the battery works in a suitable temperature range, a new design for distributed liquid cooling plate is proposed, and a battery thermal management system(BTMS) for cylindrical power battery pack based on the proposed cooling plate is also investigated. To verify the accuracy of the battery model and battery pack numerical calculation model used for simulation, an experiment is conducted for the liquid cooling BTMS. The influence of key working parameters, including the cooling water inlet flow, ambient temperature and working conditions, are investigated. The results show that at the discharge rate of 3 c, the best cooling performance can be achieved when the total inlet mass flow rate is 3.2 g/s and the flow distribution is 3:1:1:3. The obtained maximum temperature is 29.6°c and the maximum temperature difference is 2.1°c. When the ambient temperature is in the range of 20°c to 50°c, the proposed BTMS can keep the temperature of battery pack in the proper range. Finally, different inlet flow rates are recommended according to different battery working states.

关键词： lithium battery battery model battery thermal management liquid cooling plate distributed cooling

Homozygous phytosterolemia and a literature review:A case report

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World Journal of clinical cases 2025年第10期13卷 46-52页

作者： chun-Xin Jiang Guang yang Lian-Ping Shi Peng-Yu Su Department of cardiovascular North China University of Science and Technology Affiliated HospitalTangshan 063000Hebei ProvinceChina

BAcKGROUND Phytosterolemia,also known as sitosterolemia,is a rare autosomal recessive disease characterized by elevated plasma plant sterol levels and xanthomata,which is easily misdiagnosed as familial *** with homozygous phytosterolemia often have severe clinical manifestations,with xanthomata in childhood and premature *** patient had a milder clinical *** SUMMARY This report describes a patient with homozygous phytosterolemia who presented with only elevated cholesterol and low-density lipoprotein cholesterol(LDL-c)without xanthomata,arteriosclerosis,or hematological *** mutation of ABcG5 which encodes an ATP-binding cassette transporter,was detected by whole exome sequencing and diagnosed as *** of the patient’s plasma plant sterol levels detected significant elevations in stigmasterol,rapeseed oil-derived plant sterol,andβ-glutaminol *** was started and a low plant sterol diet was *** patient’s blood lipid profile was reexamined one month later and showed significant decreases in total cholesterol and LDL-c *** has similar clinical features as familial hypercholesterolemia,is highly susceptible to misdiagnosis,and has a very low incidence,and therefore clinicians need to consider a genetic diagnosis of a definitively hyperlipidemic disorder when statin drugs fail to lower lipid *** Phytosterolemia is easily misdiagnosed as familial hypercholesterolaemia and can be treated by dietary modification and cholesterol absorption inhibitors to lower blood lipids.

关键词： Hypercholesterolemia cholesterol Low-density lipoprotein Phytosterolemia Liquid chromatography ABcG5/ABcG8 Sitosterolemia