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Model Parameters Identification and Backstepping Control of Lower Limb Exoskeleton Based on Enhanced Whale Algorithm

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 100-114页

作者： yan Shi Jiange kou Zhenlei Chen yixuan Wang Qing Guo School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China

Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction ***,due to unknown model parameters such as the mass,moment of inertia and mechanical size,the dynamic model of exoskeletons is difficult to ***,an enhanced whale optimization algorithm(EWOA)is proposed to identify the exoskeleton model ***,the periodic excitation trajectories are designed by finite Fourier series to input the desired position demand of exoskeletons with mechanical physical *** a backstepping controller based on the identified model is adopted to improve the human-robot wearable comfortable performance under cooperative ***,the proposed Model parameters identification and control are verified by a two-DOF exoskeletons *** knee joint motion achieves a steady-state response after 0.5 ***,the position error of hip joint response is less than 0.03 rad after 0.9 *** addition,the steady-state human-robot interaction torque of the two joints is constrained within 15 n·*** research proposes a whale optimization algorithm to optimize the excitation trajectory and identify model ***,an enhanced mutation strategy is adopted to avoid whale evolution’s unsatisfactory local optimal value.

关键词： Parameter identification Enhanced whale optimization algorithm(EWOA) Backstepping Human-robot interaction Lower limb exoskeleton

On the variable timing behavior of PSR B0540-69:an almost excellent example to study the pulsar braking mechanism

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Research in Astronomy and Astrophysics 2016年第5期16卷 81-86页

作者： Fei-Fei kou Zi-Wei Ou Hao Tong Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

PSR B0540-69 has a braking index measurement in its persistent state： n = 2.129± 0.012. Recently, it has been reported to have changes in its spin-down state： a sudden 36% increase in the spin- down rate. Combining the persistent state braking index measurement with different spin-down states, PSR B0540-69 is more powerful than intermittent pulsars in constraining pulsar spin-down models. The pulsar wind model is applied to explain the variable timing behavior of PSR B0540-69. The braking index of PSR B0540-69 in its persistent state results from the combined effect of magnetic dipole radiation and particle wind. The particle density reflects the magnetospheric activity in real-time and may be responsible for the changing spin-down behavior. Corresponding to the 36% increase in the spin-down rate of PSR B0540-69, the relative increase in the particle density is 88% in the vacuum gap model. The braking index calculated with the model in the new state is n = 1.79. Future observations that measure the braking index of PSR B0540-69 in the new spin-down state will be very powerful in distinguishing between different pulsar spin-down models and different particle acceleration models in the wind braking scenario. The variable timing behavior of PSR J 1846-0258 is also understandable in the pulsar wind model.

关键词： pulsars: general -- pulsars: individual (PSR B0540-69 PSR J 1846-0258) -- stars: neutron-- wind

Synthesis, crystal structures and magnetic properties of cyanide-bridged macrocyclic complexes

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Science China Chemistry 2009年第9期52卷 1444-1450页

作者： nI ZhongHai ZHAnG LiFang CUI AiLi kou HuiZhong Department of Chemistry Tsinghua UniversityBeijing 100084China Department of Chemistry Shandong UniversityJinan 250100China

Three cyanide-bridged dodecanuclear macrocyclic wheel-like complexes [Cr(bpmb)(Cn)2]6[Mn(5-Brsalpn)]6·12H2O (1), [Co(bpmb)(Cn)2]6[Mn(5-Brsalpn)]6·12H2O (2) and [Co(bpmb)(Cn)2]6[Mn(5-Clsalpn)]6·24H2O·8CH3Cn (3) [bpmb2?= 1,2-bis(pyridine-2-carboxamido)-4-methylbenzenate dianion; 5-Brsalpn2? = n,n′-propylenebis(5-bromosalicylideneaminato) dianion; 5-Clsalpn2? = n,n′-propylenebis(5-chlorosalicylideneaminato) dianion] have been synthesized and their crystal structures and magnetic properties have been investigated. The three compounds are structurally isomorphous and consist of alternating Mn(III)-Schiff base cations and [M(bpmb)(Cn)2]? anions, generating cyanide-bridged nanosized dodecanuclear macrocyclic structures with an approximate diameter of 2 nm. The study of the magnetic properties of complex 1 reveals an antiferromagnetic interaction between the Cr(III) and Mn(III) ions through the cyanide bridges. A best-fit to the magnetic susceptibility of the complex leads to a magnetic coupling constant of J CrMn = ?2.65(6) cm?1 on the basis of a one-dimensional alternating chain model with the Hamiltonian $ H = - J_{CrMn} \sum\limits_{i = 0}^n {S_i \cdot S_{i + 1} } $ .

关键词： polynuclear complex crystal structure magnetic property cyanide chromium manganese

Synthesis and Crystal Structure of a Sodium Monosulfuron-ester (n-[2'-(4-Methyl)pyrimidinyl]-2-carbomethoxy Benzyl Sulfonylurea Sodium)

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1414-1417页

作者： kou Jun-Jie LI Zheng-Ming SOnG Hai-Bin national Pesticide Engineering Research Center State Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 China

Monosulfuron-ester is a novel sulfonylurea herbicide with ultra-low dosage Herein sodium monosulfuron-ester was synthesized and its crystal structure was determined by X-ray diffraction method. The title compound belongs to monoclinic, space group P21/c with a = 9.335（5）, b = 20.632（12）, c = 13.853（8） A, β = 107.193（9）°, Mr = 487.46, Z = 4, Dc = 1.270 g/cm^3, μ = 0.293 mm^-1, F（000） = 1015, R = 0.0859 and wR = 0.2633. In the title compound, na coordinates with n（1）, O（1） and O（3） from one monosulfuron-ester molecule, n（4A） and O（5A） from the other monosulfuron-ester molecule and one oxygen atom from DMSO to give six coordination bonds.

关键词： sulfonylurea sodium monosulfuron-ester crystal structure

A genetic algorithm based entity resolution approach with active learning

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Frontiers of Computer Science 2017年第1期11卷 147-159页

作者： Chenchen SUn Derong SHEn yue kou Tiezheng nIE Ge yU Sohool of Information Science and Engineering Northeastern University Shenyang 110819 China

Entity resolution is a key aspect in data quality and data integration, identifying which records correspond to the same real world entity in data sources. Many existing ap- proaches require manually designed match rules to solve the problem, which always needs domain knowledge and is time consuming. We propose a novel genetic algorithm based en- tity resolution approach via active learning. It is able to learn effective match rules by logically combining several different attributes＇ comparisons with proper thresholds. We use ac- tive learning to reduce manually labeled data and speed up the learning process. The extensive evaluation shows that the proposed approach outperforms the sate-of-the-art entity res- olution approaches in accuracy.

关键词： entity resolution genetic algorithm active learning data quality data integration

Genome evolution of novel influenza A (H1n1) viruses in humans

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Chinese Science Bulletin 2009年第13期54卷 2159-2163页

作者： kou Zheng HU Songnian LI TianXian State Key Laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China Beijing Institute of Genome Chinese Academy of Sciences Beijing 100029

The epidemic situation of A H1n1 flu arose in north America in April 2009,which rapidly expanded to three continents of Europe,Asia and Africa,with the risk ranking up to *** May 13th,the flu virus of A H1n1 had spread into 33 countries and regions,with a laboratory confirmed case number of 5728,including 61 *** on IRV and EpiFluDB database,425 parts of A H1n1 flu virus sequence were achieved,followed by sequenced comparison and evolution *** results showed that the current predominant A H1n1 flu virus was a kind of triple reassortment A flu virus:(i) HA,nA,MP,nP and nS originated from swine influenza virus;PB2 and PA originated from bird influenza virus;PB1 originated from human influenza virus.(ii) The origin of swine influenza virus could be subdivided as follows:HA,nP and nS originated from classic swine influenza virus of H1n1 subtype;nA and MP originated from bird origin swine influenza virus of H1n1 subtype.(iii) A H1n1 flu virus experienced no significant mutation during the epidemic spread,accompanied with no reassortment of the virus *** the paper,the region of the representative strains for sequence analysis(A/California/04/2009(H1n1) and A/Mexico/4486/2009(H1n1)) included USA and Mexico and was relatively wide,which suggested that the analysis results were convincing.

关键词：禽流感病毒基因组进化人类猪流感病毒生理盐水序列比较病毒亚型鸟类起源

Quantum critical duality in two-dimensional Dirac semimetals

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Chinese Physics B 2019年第1期28卷 584-593页

作者： Jiang Zhou ya-Jie Wu Su-Peng kou Department of Physics Guizhou University School of Science Xi’an Technological University Department of Physics Beijing normal University

Quantum criticality is closely related to the existence of two phases with unrelated symmetry breaking. In this paper,we study néel and Kekulé valence bond state(VBS) quantum criticality in Dirac semimetals with four-fermion *** results show that all possible dynamical masses yield the same critical coupling, which exhibits the phenomenon that all possible phases meet at a multicritical point(e.g., a tricritical point for the néel, Kekulé-VBS and semimetallic phases).In terms of the well-established Wess–Zumino–Witten field theory, we investigate the typical criticality for the transition between néel and Kekulé-VBS phases, and the compatible néel–Kekulé-VBS mass matrices imply the existence of a nonLandau transition between the néel and Kekulé-VBS phases. We show the existence of mutual duality in the defect-driven néel–Kekulé-VBS transition near the non-Landau critical point and find that this mutual duality results from the presence of a mutual Chern–Simons term. We also study the mutual duality based on dual topological excitations.

关键词： quantum criticality duality semimetal–insulator transition spin–charge separation

Application of unified protocol as a transdiagnostic treatment for emotional disorders during COVID-19: An internet-delivered randomized controlled trial

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World Journal of Clinical Cases 2022年第24期10卷 8599-8614页

作者： kou yan Mohammad Hassan yusufi nabi nazari School of Humanities and Education Xi'an Eurasia UniversityXi'an 710065Shaanxi ProvinceChina Education Administration Bamyan UniversityBamyan 22502Afghanistan Department of Psychology Faculty of Human SciencesLorestan UniversityKhorramabadLorestanIran

BACKGROUnD The coronavirus disease 2019(COVID-19)pandemic has been an emotionally challenging time,especially for young *** is associated with a substantial increase in the prevalence of mental health problems,negative symptoms,and stressful experiences that compromise *** low-income countries,internet-delivered psychological services could have a remarkable impact on the population’s mental health,given the lack of mental health *** To investigate the efficacy of internet-delivered cognitive-behavior therapy(CBT)-transdiagnostic intervention for adults with emotional *** In this internet-delivered randomized controlled trial,102 students with an emotional disorder(mean age=28.20 years,standard deviation=5.07)were randomly allocated to receive unified protocol(UP)(n=51)or treatment as the usual *** a semi-structured clinical interview,participants completed an online survey including the Overall Anxiety Severity and Impairment Scale,Overall Depression Severity and Impairment Scale,Difficulties in Emotion Regulation Scale,Positive and negative Affect Schedule,and Emotional Style *** The participants showed a high degree of *** total,78%(n=40)of the experimental group participants completed the UP *** the intention to treat procedure,the results of the analysis of covariance indicated that participants who received UP showed statistically significant changes in depression symptoms[Cohen’s d=-1.50 with 95%confidence interval(CI):-1.90 to-1.10],anxiety(Cohen’s d=-1.06 with 95%CI:-1.48 to-0.65),difficulties with emotion regulation(Cohen’s d=-0.33 with 95%CI:-0.7 to-0.06),positive affect(Cohen's d=1.27 with 95%CI:0.85 to 1.68),negative affect(Cohen’s d=-1.04 with 95%CI:-1.46 to-0.63),and healthy emotionality(Cohen’s d=0.53 with 95%CI:0.09 to 0.13)compared with the control *** This study’s findings highlight the potential value of transdiagnostic interne

关键词： Unified protocol COVID-19 Internet-delivered Emotion regulation Transdiagnostic Depression Anxiety

Effect of Fe/Al Hydroxides on Desorption of K^+ and nH_4^+ from Two Soils and Kaolinite

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Pedosphere 2013年第1期23卷 81-87页

作者： WAnG yan-Ping XU Ren-kou LI Jiu-yu State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences

Potassium （K） and nitrogen （n） are essential nutrients for plants. Adsorption and desorption in soils affect K＋ and nH4＋ avail- abilities to plants and can be affected by the interaction between the electrical double layers on oppositely charged particles because the interaction can decrease the surface charge density of the particles by neutralization of positive and negative charges. We studied the effect of iron （Fe）/aluminum （Al） hydroxides on desorption of K＋ and nH4＋ from soils and kaolinite and proposed desorption mechanisms based on the overlapping of diffuse layers between negatively charged soils and mineral particles and the positively charged Fe/Al hydroxide particles. Our results indicated that the overlapping of diffuse layers of electricM double layers between positively charged Fe/Al hydroxides, as amorphous Al（OH）3 or Fe（OH）3, and negatively charged surfaces from an Ultisol, an Alfisol, and a kaolinite standard caused the effective negative surface charge density on the soils and kaolinite to become less negative. Thus the adsorption affinity of these negatively charged surfaces for K＋ and nH4＋ declined as a result of the incorporation of the Fe/Al hydroxi- des. Consequently, the release of exchangeable K＋ and nH4＋ from the surfaces of the soils and kaolinite increased with the amount of the Fe/A1 hydroxides added. The greater the positive charge on the surfaces of Fe/Al hydroxides, the stronger was the interactive effect between the hydroxides and soils or kaolinite, and thus the more release of K＋ and nH4＋. A decrease in pH led to increased positive surface charge on the Fe/Al hydroxides and enhanced interactive effects between the hydroxides and soils/kaolinite. As a result, more K＋ and nH4＋ were desorbed from the soils and kaolinite. This study suggests that the interaction between oppositely charged particles of variable charge soils can enhance the mobility of K＋ and nH4＋ in the soils and thus increase their leaching loss.

关键词： amorphous Al(OH)3 amorphous Fe(OH)3 electrical double layer surface charge variable charge soil