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Lubrication Performance of Connecting-Rod and Main Bearing in Di erent Engine Operating Conditions

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 81-92页

作者： Jun Sun Biao Li Shaoyu Zhu Enming Miao Hu Wang Xiaoyong Zhao Qin Teng School of Automotive and Transportation Engineering Hefei University of Technology School of Mechanical Engineering Hefei University of Technology School of Instrument Science and Opto-electronics Engineering Hefei University of Technology

Only the lubrication performance at rated engine operating condition was generally analyzed in current design and research of engine connecting-rod and main bearing. However, the actual engine(especially vehicle engine) does not always operate in rated operating condition and its operating condition changes constantly. In this paper, a fourstroke four-cylinder engine is taken as the studying object, the load and lubrication of connecting-rod and main bearing in di erent operating conditions are analyzed. The load of connecting-rod bearing is calculated by the dynamic calculation method, the loads of all main bearings are calculated by the whole crankshaft beam-element finite element method, and the lubrication performance of connecting-rod and main bearings are analyzed by the dynamic method. The results show that there are major di erences in the changes and numerical value at corresponding moment of the loads and lubrication performance of connecting-rod and main bearings in an engine operating cycle in di erent engine operating conditions; the most unfavorable case of the lubrication performance of connectingrod and main bearings may not take place in the rated engine operating condition. There are also major di erences between the lubrication performance of connecting-rod bearing and that of main bearing and between the lubrication performances of main bearings one another. Therefore, it will not be reasonable that the lubrication performance of a certain connecting-rod bearing or main bearing is analyzed in the design of the engine bearing. It is necessary to analyze simultaneously the lubrication performances of all bearings in di erent engine operating conditions.

关键词： Lubrication Connecting-rod bearing Main bearing Engine Operating condition

Improved non-singular local boundary integral equation method

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Applied Mathematics and Mechanics(English Edition) 2007年第8期28卷 1093-1099页

作者：付东杰陈海波张培强 Department of Modern Mechanics university of Science and technology of China hefei 230026 P.R.China CAS Key Laboratory of Mechanical Behavior and Design of MaterialsUniversity of Science and Technology of ChinaHefei 230026P.R.China

When the source nodes are on the global boundary in the implementation of local boundary integral equation method （LBIEM）, singularities in the local boundary integrals need to be treated specially. In the current paper, local integral equations are adopted for the nodes inside the domain and moving least square approximation （MLSA） for the nodes on the global boundary, thus singularities will not occur in the new al- gorithm. At the same time, approximation errors of boundary integrals are reduced significantly. As applications and numerical tests, Laplace equation and Helmholtz equation problems are considered and excellent numerical results are obtained. Furthermore, when solving the Helmholtz problems, the modified basis functions with wave solutions are adapted to replace the usually-used monomial basis functions. Numerical results show that this treatment is simple and effective and its application is promising in solutions for the wave propagation problem with high wave number.

关键词： meshless method local boundary integral equation method moving least square approximation singular integrals

An Efficient Evaluation and Vector Generation Method for Observability-Enhanced Statement Coverage

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Journal of Computer Science & technology 2005年第6期20卷 875-884页

作者：鲁巍杨修涛吕涛李晓维 Institute of Computing technology Chinese Academy of Sciences Beijing 100080 P.R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P.R. China School of Computer and Information Hefei University of Technology Hefei 230009 P.R. China

Coverage evaluation is indispensable for verification via simulation. As the functional complexity of modern design is increasing at a breathtaking pace, it is requisite to take observability into account. Unfortunately, nowadays coverage metrics taking observability into account are not very satisfactory. On the one hand, for the observability assessment algorithms proposed up to now, the overhead of computing is large, so they could not be integrated into simulation tools easily. On the other hand, the vector generation methods involving the metrics taking observability into account are not very efficient, and there exists a disconnection between these metrics and the vector generation process. In this paper, some original ideas for the problems above are presented. （1） Precise and concise abstract representations from HDL （Hardware Description Language） descriptions at RTL （Register Transfer Level） are presented to model observability information. （2） A novel observability evaluation method based on the proposed models is introduced. This method is more computationally efficient than prior efforts to assess observability and it could be integrated into compilers and simulators easily. （3） A new simulation vector generation procedure involving the observability-enhanced statement coverage metric is developed. The method is simulation：based and driven by the distribution of unobserved statements. During this procedure, the proposed algorithm always tries to cover all unobserved statements, and reduce unnecessary backtracking, so it is efficient. The methods proposed have been implemented as a prototype tool for VHDL designs, and the results on benchmarks show significant benefits.

关键词： design verification simulation coverage metrics observability vector generation

Development of a combined interferometer using millimeter wave solid state source and a far infrared laser on ENN's Xuan Long-50(EXL-50)

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Plasma Science and technology 2022年第6期24卷 23-31页

作者：解家兴魏学朝刘海庆李松健张际波姚远王云飞揭银先 Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China university of Science and technology of China Hefei 230026People’s Republic of China ENN Science and technology Development Co. LtdLangfang 065001People’s Republic of China Interdisciplinary Graduate School of Engineering Sciences Kyushu UniversityKasuga 816-8580Japan

A millimeter wave solid state source—far infrared laser combined interferometer system(MFCI)consisting of a three-channel 890 GHz hydrogen cyanide(HCN)laser interferometer and a threechannel 340 GHz solid state source interferometer(SSI)is developed for real-time line-integrated electron density feedback and electron density profile of the EXL-50 spherical tokamak *** interferometer system is a Mach–Zehnder type,with all probe-channels measured vertically,covering the plasma magnetic axis to the outermost closed magnetic *** HCN laser interferometer uses an HCN laser with a frequency of 890 GHz as a light source and modulates a100 k Hz beat signal by a rotating grating,giving a temporal resolution of 10μ*** SSI uses two independent 340 GHz solid-state diode sources as the light source,the frequency of the two sources is adjustable,and the temporal resolution of SSI can reach 1μs by setting the frequency difference of the two lasers at 1 *** main optical path of the two interferometers is compactly installed on a set of double-layer optical platform directly below *** optical path design using corner cube reflectors avoids the large support *** the probebeams of two wavelengths,then the phase error caused by vibration can be *** present,the phase noise of the HCN Interferometer is 0.08 rad,corresponding to a line-integrated electron density of 0.88×10^(17)m^(-2),one channel of measuring result was obtained by the MFCI system,and the highest density measured is about 0.7×10^(19)m^(-2).

关键词： plasma diagnostics—interferometry spectroscopy and imaging nuclear instruments and methods for hot plasma diagnostics

Adaptive Fuzzy Sliding Mode Controller with Nonlinear Observer for Redundant Manipulators Handling Varying External Force

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Journal of Bionic Engineering 2016年第4期13卷 600-611页

作者： Jun He Minzhou Luo Qingqing Zhang Jianghai Zhao Linsen Xu Department of Automation School of Information Science of Technology University of Science and Technology of China HeJei 230026 China Institute of Advanced Manufactcturing and technology Hefei Institute of Physical Science Chinese Academy of Sciences Changzhou 213164 China School of Mechanical and Electrical Engineering Hohai University Changzhou 213264 China School of Engineering Science University of Seience and Technology of China Hefei 230026 China

An Adaptive Fuzzy Sliding Mode Controller with Nonlinear Observer （AFSMCO） for the redundant robotic manipulator is proposed in this paper. This approach could achieve a precise trajectory tracking for a robot manipulator in the presence of uncertainties and disturbances. Primarily, a suitable observer using the recursive algorithm is presented for an accurate estima- tion of external disturbances caused by the varying external force. Secondly, the adaptive fuzzy logic is designed to approximate the parameters of the sliding mode controller （AFSMC） to avoid chattering in real time. Moreover, it is shown using the Lyapunov theory that the tracking error asymptotically converges to zero. Finally, the effectiveness of the proposed control approach and theoretical discussion are demonstrated by simulation results on a 7-1ink robot and tested on a 7-DOF manipulator platform.

关键词： fuzzy logic adaptive control redundant manipulators nonlinear observer

High-Fidelity Geometric Gates with Single Ions Doped in Crystals

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Chinese Physics Letters 2021年第9期38卷 58-62页

作者：郭奥林涂涛朱乐天李传锋 Key Laboratory of Quantum Information University of Science and Technology of ChinaChinese Academy of SciencesHefei 230026China

Single rare-earth ions doped in solids are one kind of the promising candidates for quantum nodes towards a scalable quantum *** a universal set of high-fidelity gate operations is a central requirement for functional quantum *** we propose geometric gate operations using the hybridized states of electron spin and nuclear spin of an ion embedded in a *** fidelities of these geometric gates achieve 0.98 in the realistic experimental *** also show the robustness of geometric gates to pulse fluctuations and to environment *** results provide insights for geometric phases in dissipative systems and show a potential application of high fidelity manipulations for future quantum internet nodes.

关键词： quantum operations solids

Giant magnetoresistance effect and temperature dependence of magnetoresistance in La_(2/3)Ca_(1/3)MnO_2 thin film

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Science China Mathematics 1996年第6期39卷 624-630页

作者：李可斌刘玲孙建三许小军方军王胜王福堂曹效文朱警生张裕恒 Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China High Field Laboratory Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China Structure Research Laboratory University of Science and Technology of China Hefei 230026 China

Magnetoresistanoe in the temperature region from 300 K to liquid helium temperature has been measured on good (100) oriented La2/3Ca1/3MnO2 thin films prepared by d.c. magnetron sputtering on ZrO2 (100) substrates. It is found that there appears a resistance peak at about TP = 72K at zero magnetic field, and this peak moves to higher temperature with increasing field H, and R decreases simultaneously. However, the magnetoresistance ratio MR = 5R /R (H) = (Ro~ RH) /RH has a different temperature dependence. There are also MR peaks, but the temperature of maximum MR is at about 25 K which does not change with changing external magnetic field. The heat treatment (annealed at 700C in 105’Pa O2 for 30min) will make R reduce dramatically and has an effect on the temperature dependence of R and its MR.

关键词： La2/3Ca1/3MnO2 thin film magnetoresistance negative giant magnetoresistance.

Self-assembly nanomicelle-microneedle patches with enhanced tumor penetration for superior chemo-photothermal therapy

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Nano Research 2022年第3期15卷 2335-2346页

作者： Ying Sun Minglong Chen Dan Yang Wanbing Qin Guilan Quan Chuanbin Wu Xin Pan School of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou 510006China College of Pharmacy Jinan UniversityGuangzhou 510632China Jieyang Affiliated Hospital Sun Yat-Sen UniversityGuangzhou 522091China Physical Sciences at the Microscale Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Nanomedicine with high specificity has been a promising tool for cancer diagnosis and ***,the successful application of nanoparticle-based superficial cancer therapy is severely hindered by restricted deep tumor tissue accumulation and ***,a self-assembly nanomicelle dissolving microneedle(DMN)patch according to the“nano in micro”strategy was conducted to co-deliver a first-line chemotherapeutic agent paclitaxel(PTX),and a photosensitizer IR780(PTX/IR780-NMs@DMNs)for chemo-photothermal synergetic melanoma *** direct insertion into the tumor site,DMNs created a regular and multipoint three-dimensional drug depot to maximize the tumor *** by the DMN dissolution,the composition of the needle matrixes self-assembled into nanomicelles,which could efficiently penetrate deep tumor *** laser irradiation,the nanomicelles could not only ablate tumor cells directly by photothermal conversion but also trigger PTX release to induce tumor cell *** vivo results showed that compared with intravenous injection,IR780 delivered by PTX/IR780-NMs@DMNs was almost completely accumulated at the tumor *** antitumor results revealed that the PTX/IR780-NMs@DMNs could effectively eliminate tumors with an 88%curable rate without any damage to normal *** work provides a versatile and generalizable framework for designing self-assembly DMN-mediated combination therapy to fight against superficial cancer.

关键词： dissolving microneedle tumor penetration nanomicelle superficial tumor chemo-photothermal therapy

Free Radical Pathway Cleavage of C-O Bonds for the Synthesis of Alkylboron Compounds

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Chinese Journal of Chemistry 2019年第1期37卷 11-18页

作者： Xi Lu Zhen-Qi Zhang Lu Yu Ben Zhang Bing Wang Tian-Jun Gong Chang-Lin Tian Bin Xiao Yao Fu hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomcass Clean EnergyiChEMUniversity of Science and Technology of ChinaHefeiAnhui 230026China High Magnetic Field Laboratory Chinese Academy of SciencesHefeiAnhui 230031China School of Life Sciences University of Science and Technology of ChinaHefeiAnhui 230027China

Sumrnary of main observation and conclusion We report a silver-catalyzed borylation of alkyl tosylates,which provides a new method for the synthesis of all 详细信息

Sumrnary of main observation and conclusion We report a silver-catalyzed borylation of alkyl tosylates,which provides a new method for the synthesis of all

关键词： Sumrnary report work