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On the Possibility to Construct Gravitational Eye

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Communications in Theoretical Physics 2007年第5期47卷 851-860页

作者： CHEN ying-tian Department of Astronomy and Applied Physics University of Science and Technology of China Hefei 230026 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Cavendish Laboratory University of Cambridge Cambridge U.K.

The possibility of modifying a conventional Cavendish torsion pendulum into a half-armed pendulum oscillator to measure the horizontal gravitational acceleration is discussed. A new kind of gravitational detector, gravieye, as we named, can be made by a proper combination of such oscillators to ＂see＂ remote objects and to be used, e.g. to detect the movement of huge mass at a long distance.

关键词： gravitational eye Cavandish torsion pendulum gravitational experiment gravieye

Face Age Estimation Based on CSLBP and Lightweight Convolutional Neural Network

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Computers, Materials & Continua 2021年第11期69卷 2203-2216页

作者： Yang Wang ying tian Ou tian School of Computer Science and Software Engineering University of Science&Technology LiaoningAnshan114051China Medical and Health Sciences University of WollongongNSW2522Australia

As the use of facial attributes continues to expand,research into facial age estimation is also *** face images are easily affected by factors including illumination and occlusion,the age estimation of faces is a challenging *** paper proposes a face age estimation algorithm based on lightweight convolutional neural network in view of the complexity of the environment and the limitations of device computing *** face age estimation based on Soft Stagewise Regression Network(SSR-Net)and facial images,this paper employs the Center Symmetric Local Binary Pattern(CSLBP)method to obtain the feature image and then combines the face image and the feature image as network input *** feature images to the convolutional neural network can improve the accuracy as well as increase the network model *** experimental results on IMDB-WIKI and MORPH 2 datasets show that the lightweight convolutional neural network method proposed in this paper reduces model complexity and increases the accuracy of face age estimations.

关键词： Face age estimation lightweight convolutional neural network CSLBP SSR-Net

New method for multibody dynamics based on unknown constraint force

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Science China(Technological Sciences) 2024年第3期67卷 791-808页

作者： tian ying JIA yingHong ZHANG Jun School of Astronautics Beihang UniversityBeijing 100191China Beijing Institute of Control Engineering Beijing 100190China National Laboratory of Space Intelligent Control Beijing 100190China

This paper presents a new method for the dynamics of multibody systems based on unknown constraint force. The method can uniformly solve multibody systems with typical configurations, including the system with rigid-flexible coupling, the system in tree topology, and the system with loop constraints. Unlike common methods, the proposed method can model the loop system without “cutting off” loop constraints, leading to the exact same modelling process as the tree-like system performs. Based on graph theory, a topological record matrix M_(rec) is proposed to capture the arbitrary system configuration. Moreover, constraint forces are selected as the key variables in semi-recursive framework. With the recursive kinematics relationship between adjacent bodies, the constraint force equation is further assembled to achieve the full-state system solution. The numerical simulations demonstrate the accuracy of the proposed method.

关键词： multibody system dynamic modelling rigid-flexible coupling unknown constraint force graph theory semi-recursive algorithm

Process optimization of an industrial acetic acid dehydration progress via heterogeneous azeotropic distillation

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1631-1643页

作者： Xiuhui Huang Zeqiu Li ying tian School of Energy and Power Engineering University of Shanghai for Science and Technology School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology

The simulated process model of the HAc dehydration process under actual overloaded condition was conducted by amending the model of standard condition in our previous work using the process data collected from actual production. Based on the actual process model, the operation optimization analysis of each plant(HAc dehydration column, decanter and NPA recycle column) was conducted using Residue Curve Maps(RCMs),sensitivity analysis and software optimization module. Based on the optimized parameters, the influence of feed impurity MA and the temperature of decanter on the separating effect and energy consumption of the whole process were analyzed. Then the whole process operation optimizing strategy was proposed with the objective that the total reboiler duty Q Total of C-1 and C-3 reaches the minimum value, keeping C-1 and C-3 at their optimized separation parameters obtained above, connecting all the broken recycle and connection streams, and using the temperature of D-1 as operation variable. The optimization result shows that the total reboiler duty Q Total of the whole process can reach the minimum value of 128.32 × 10~6 k J·h^(-1) when the temperature of decanter is 352.35 K, and it can save 5.94 × 10~6 k J·h^(-1), about 2.56 t·h^(-1) low-pressure saturated vapor.

关键词： Acetic acid dehydration Azeotropic distillation Process simulation Operation optimization

Properties of a High Hydrolysis Stable Nitrogenous Benzo-heterocyclic Borates

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China Petroleum Processing & Petrochemical Technology 2020年第2期22卷 37-45页

作者： tian ying Lyu Ya East China University of Science and Technology Shanghai 200237

A benzotriazole-containing derivative was synthesized via the Mannich *** structure was characterized by NMR *** utilizing computational chemistry and molecular simulation,the calculation and mapping of atomic charge and frontier molecular orbitals with complex structure of the borate were carried *** acid number of BTBE(nitrogen-containing heterocyclic borate)was determined by the standard test method for acid number and the open observation *** results showed that BTBE had a low initial acid number,because the acid number was changed only after 72 hours of hydrolysis,and it was negative after the hydrolysis reached 120 *** extreme-pressure friction resistance of BTBE and other four base oils was also *** 5 kinds of base oils,the friction experiment was carried out under a load of 30 kgf,and the BTBE showed a lowest wear scar diameter(0.365 mm)along with a highest maximum non-seizure *** results showed that the EP friction resistance of BTBE was stronger than that of other four base oils under the same test *** results of hydrolysis performance showed that the synthesized nitrogencontaining heterocyclic borate had a high resistance to hydrolysis,while demonstrating broad application prospects.

关键词： borate Mannich reaction acid number hydrolysis EP friction resistance

Preparation of a PTE simulacrum based on surface molecular imprinting

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Chinese Chemical Letters 2011年第4期22卷 493-496页

作者： Yong Guo ying Yang tian ying Guo Key Laboratory of Functional Polymer Materials Ministry of Education Institute of Polymer Chemistry Nankai University Tianjin 300071 China

Firstly,we synthesized N-methacryloyl-histidine monomer and N-methacryloyl-histidine-Cu^2＋ complex（MAH-Cu^2＋）.Then the molecular imprinting polymers（MIP） has been prepared by surface grafting on uniform polystyrene（PS） core using reversible addition-fragmentation transfer polymerization（RAFT） with MAH-Cu^2＋ as the functional monomer,methyl paraoxon as the template to simulate phosphodiesterase（PTE）.Finally,we have investigated the catalytic hydrolytic activities of MIP and non-imprinting polymers（NIP） to the template methyl paraoxon and the template analogue ethyl paraoxon respectively by UV *** results showed that the catalytic hydrolytic activity of MIP to the template methyl paraoxon was highest and the value of k is 8.67×10^-5 mmol L^-1 min^-1,3.89-fold higher than MIP to the template analogue ethyl paraoxon,2.79-fold higher than NIP to the template methyl *** KM,rm of MSP are also determined,and KM = 3.95×10^-4）mol/L,rm = 2.12μmol/ *** MIP can be reused with only lose 7%of catalytic activity for four cycles.

关键词： Molecular imprinting Surface grafting Catalytic hydrolysis Paraoxon

Adaptive Coordinated Path Tracking Control Strategy for Autonomous Vehicles with Direct Yaw Moment Control

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Chinese Journal of Mechanical Engineering 2022年第1期35卷 223-237页

作者： ying tian Qiangqiang Yao Peng Hang Shengyuan Wang Beijing Key Laboratory of Powertrain for New Energy Vehicle School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

It is a striking fact that the path tracking accuracy of autonomous vehicles based on active front wheel steering is poor under high-speed and large-curvature *** this study,an adaptive path tracking control strategy that coordinates active front wheel steering and direct yaw moment is proposed based on model predictive control *** recursive least square method with a forgetting factor is used to identify the rear tire cornering stiffness and update the path tracking system prediction *** adaptively adjust the priorities of path tracking accuracy and vehicle stability,an adaptive strategy based on fuzzy rules is applied to change the weight coefficients in the cost *** adaptive control strategy for coordinating active front steering and direct yaw moment is proposed to improve the path tracking accuracy under high-speed and large-curvature *** ensure vehicle stability,the sideslip angle,yaw rate and zero moment methods are used to construct optimization constraints based on the model predictive control *** is verified through simulation experiments that the proposed adaptive coordinated control strategy can improve the path tracking accuracy and ensure vehicle stability under high-speed and largecurvature conditions.

关键词： Autonomous vehicles Path tracking Model predictive control Adaptive coordinated

Effect of solution cooling rate on the γ′ precipitation behaviors of a Ni-base P/M superalloy

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Journal of University of Science and Technology Beijing 2008年第6期15卷 729-734页

作者： Gaofeng tian Chengchang Jia ying Wen Benfu Hu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of cooling rate on the cooling γ′ precipitation behaviors was investigated in a Ni-base powder/metallurgy （P/M） superalloy （FGH4096）. The empirical equations were established between the cooling rate and the average sizes of secondary and tertiary γ′ precipitates within grains and tertiary γ′ precipitates at grain boundaries, as well as the apparent width of grain boundaries. The results show that the average sizes of secondary or tertiary γ′ precipitates are inversely correlated with the cooling rate. The shape of secondary γ′ precipitates within grains changes from butterfly-like to spherical with the increase of cooling rate, but all the tertiaryγ′ precipitates formed are spherical in shape. It is also found that tertiary γ′ may be precipitated in the latter part of the cooling cycle only if the cooling rate is not faster than 4.3℃/s, and the apparent width of grain boundaries decreases linearly with the increase of cooling rate.

关键词： powder metallurgy Ni-base superalloy precipitates cooling rate

Dynamic consequences of mutating the typical HPGG motif of apocytochrome b_5 revealed by computer simulation

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Chinese Chemical Letters 2009年第5期20卷 631-634页

作者： ying Wu Lin tian Lei ying Li Fu Liao School of Chemistry and Chemical Engineering University of South China Hengyang 421001 China Department of Chemistry University of Illinois at Urbana-Champaign Urbana IL 61801 USA Chemical Biology Lab Department of Chemistry Fudan University Shanghai 200433 China

Apocytochrome b5 with a typical heme-binding motif of HPGG, and its variants with mutated motifs, GPGG, GPGH, HVGG, and HPGP, have been subjected to molecular dynamics simulation. Comparison of the dynamic consequences has revealed the crucial role of HPGG in assembling the heine group of cytochrome b5 and in modulating protein structure, property and function.

关键词： Apocytochrome b5 Heme-binding motif HPGG Molecular dynamics simulation