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Chinese Journal of Chemistry 2013年第5期31卷 607-611页

作者： ying Han Jiabin Guo jing Cao Chuanfeng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Triptycene-derived cylindrical macrotricyclic host with two dibenzo-30-crown-lO cavities could form stable 1 ： 1 complexes with not only polyether linked bisparaquat derivative but also a self-folding A-D-A guest in solu- tion and/or solid state. Moreover, it was found that switchable processes between the host and both the bisparaquat derivative and the self-folding guest could be further controlled by potassium ions.

关键词： complexation macrotricyclic host paraquat triptycene switchable

Comprehensive evaluation of machine learning algorithms applied to TBM performance prediction

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Underground Space 2022年第1期7卷 37-49页

作者： Jie Yang Saffet Yagiz ying-jing Liu Farid Laouafa Zhongtian Construction Group Co.Ltd HangzhouChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina School of Mining and Geosciences Nazarbayev UniversityNur-Sultan 010000Kazakhstan National Institute for Industrial Environment and Risks(INERIS) Verneuil-en-HalatteFrance

To date,the accurate prediction of tunnel boring machine(TBM)performance remains a considerable challenge owing to the complex interactions between the TBM and *** evolutionary polynomial regression(EPR)and random forest(RF),this study devel-ops two novel prediction models for TBM *** models can predict the TBM penetration rate and field penetration index as outputs with four input parameters:the uniaxial compressive strength,intact rock brittleness index,distance between planes of weakness,and angle between the tunnel axis and planes of weakness(a).First,the performances of both EPR-and RF-based models are examined by comparison with the conventional numerical regression method(i.e.,multivariate linear regression).Subsequently,the performances of the RF-and EPR-based models are further investigated and compared,including the model robustness for unknown datasets,interior relationships between input and output parameters,and variable *** results indicate that the RF-based model has greater prediction accuracy,particularly in identifying outliers,whereas the EPR-based model is more convenient to use by field engineers owing to its explicit *** EPR-and RF-based models can accurately identify the relationships between the input and output *** ensures their excellent generalization ability and high prediction accuracy on unknown datasets.

关键词： Tunnel boring machine Evolutionary polynomial regression Random forest Optimization Regularization

Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae

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Chemical Research in Chinese Universities 2004年第6期20卷 703-706页

作者： LIMin-jing YOUjing-yan YAOShuang DINGLan LIUZhong-ying ZHANGHan-qi CollegeofChemistry JilinUniversityChangchun130023P.R.China

Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The third procedure was microwave resonant cavity dynamic extraction(MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other.

关键词： Microwave-assisted extraction(MAE) Flavonoid Rutin Quercetin Flos Sophorae

Enhancing photon entanglement in a three-mode optomechanical system via imperfect phonon measurements

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Communications in Theoretical Physics 2022年第5期74卷 51-60页

作者： jing Qiu Dongni Chen ying-Dan Wang Stefano Chesi Beijing Computational Science Research Center Beijing 100193China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesP O Box2735Beijing100190 School of Physical Sciences University of Chinese Academy of SciencesNo.19A Yuquan Road Beijing 100049China Department of Physics Beijing Normal UniversityBeijing 100875 China

By considering a 3-mode optomechanical system formed by two cavities interacting with a common mechanical mode,we demonstrate that phonon-counting measurements lead to a significant enhancement of entanglement in the output of the two *** conclusion still holds for an inefficient detector,but the dependence on system parameters changes qualitatively from the ideal limit of perfect projective *** find non-trivial optimal points for the entanglement as functions of detector efficiency,measurement outcome,and optical drive *** characterize both the highest achievable entanglement as well as a‘typical’value,obtained at the most likely measurement *** results are well understood within an approximate analytical approach based on perturbation theory around the ideal detector limit.

关键词： optomechanical system entanglement concentration imperfect phonon measurements maximum entanglement typical entanglement

Mobility-Aware Multi-Task Migration and Offloading Scheme for Internet of Vehicles

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Chinese Journal of Electronics 2023年第6期32卷 1192-1202页

作者： LI Xujie TANG jing XU Yuan SUN ying College of Computer and Information Hohai University State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Key Lab for Wireless Sensor Network and Communication Shanghai Institute of Microsystem School of Information Engineering Jiangsu Open University

In Internet of vehicles, vehicular edge computing(VEC) as a new paradigm can effectively accomplish various tasks. Due to limited computing resources of the roadside units(RSUs), computing ability of vehicles can be a powerful supplement to computing resources. Then the task to be processed in data center can be offloaded to the vehicles by the RSUs. Due to mobility of the vehicles, the tasks will be migrated among the RSUs. How to effectively offload multiple tasks to the vehicles for processing is a challenging problem. A mobility-aware multi-task migration and offloading scheme for Internet of vehicles is presented and analyzed. Considering the coupling between migration and offloading, the joint migration and offloading optimization problem is formulated. The problem is a NP-hard problem and it is very hard to be solved by the conventional methods. To tackle the difficult problem, the idea of alternating optimization and divide and conquer is introduced. The problem can be decoupled into two sub-problems: computing resource allocation problem and vehicle node selection problem. If the vehicle node selection is given, the problem can be solved based on Lagrange function. And if the allocation of computing resource is given, the problem turns into a 0-1 integer programming problem, and the linear relaxation of branch bound algorithm is introduced to solve it. Then the optimization value is obtained through continuous iteration. Simulation results show that the proposed algorithm can effectively improve system performance.

关键词： Costs Computational modeling System performance Simulation Programming Multitasking Resource management

Surface roughness measurement and analysis of mechanical parts based on digital holography

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Advances in Manufacturing 2016年第3期4卷 217-224页

作者： Wen-jing Zhou Ke-Qin Peng ying-Jie Yu Department of Precision Mechanical Engineering ShanghaiUniversity Shanghai 200072 P. R. China

We measure the surface roughness of the mechanical parts based on digital holography. A digital off- axis hologram recording setup for reflective samples is built. Firstly, the height reconstruction error 2.3% of the setup is calibrated by using the quartz step height standard （VLSI- SHS-880QC）. Then, the standard scribed-line model and the grinding roughness specimen are selected as the test samples and their surface roughness are 0.095 6 jam and 0.025 3 jam, with errors 6.3%, 0.9%, respectively. The results are in good agreement with the given roughness parameters. At last, we also analyze the window effect of the filter on the roughness measurement value based on digital holography. In conclu- sion, the paper demonstrated effectively that the digital holography could provide the surface feature for the rough- ness measurement with high accuracy.

关键词： Digital holography - Digital off-axis hologram Roughness measurement Frequency filter window

On the energy efficiency of MIMO cooperative relaying networks

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 14-19页

作者： HUANG jing WANG ying WU Tong YU Xin-min Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal WLreless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Cooperative relaying techniques can greatly improve the capacity of the multiple input and multiple output （MIMO） wireless system. The transmit power allocation （TPA） strategies for various relaying protocols have become very important for improving the energy efficiency. This article proposes novel TPA schemes in the MIMO cooperative relaying system. Two different scenarios are considered. One is the hybrid decode-and-forward （HDF） protocol in which the zero-forcing （ZF） process is operated on relays, and the other is the decode-and-forward （DF） protocol with relay node and antenna selection strategies. The simulation results indicate that the proposed schemes can bring about significant capacity gain by exploiting the nature of the relay link. Additionally, the proposed TPA scheme in the HDF system can achieve the same capacity as the equal TPA with fewer relay nodes used. Finally, the capacity gain with the proposed schemes increases when the distribution range of relay nodes expands.

关键词： cooperative relaying transmit power allocation hybrid amplify-and-forward zero-forcing

Fast implementation of kernel simplex volume analysis based on modified Cholesky factorization for endmember extraction

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 250-257页

作者： jing LI Xiao-run LI Li-jiao WANG Liao-ying ZHAO College of Electrical Engineering Zhejiang University Institute of Computer Application Technology Hangzhou Dianzi University

Endmember extraction is a key step in the hyperspectral image analysis process. The kernel new simplex growing algorithm （KNSGA）, recently developed as a nonlinear alternative to the simplex growing algorithm （SGA）, has proven a promising endmember extraction technique. However, KNSGA still suffers from two issues limiting its application. First, its random initialization leads to inconsistency in final results; second, excessive computation is caused by the iterations of a simplex volume calculation. To solve the first issue, the spatial pixel purity index （SPPI） method is used in this study to extract the first endrnember, eliminating the initialization dependence. A novel approach tackles the second issue by initially using a modified Cholesky fac- torization to decompose the volume matrix into triangular matrices, in order to avoid directly computing the determinant tauto- logically in the simplex volume formula. Theoretical analysis and experiments on both simulated and real spectral data demonstrate that the proposed algorithm significantly reduces computational complexity, and runs faster than the original algorithm.

关键词： Endmember extraction Modified Cholesky factorization Spatial pixel purity index (SPPI) New simplex growingalgorithm (NSGA) Kernel new simplex growing algorithm (KNSGA)

Enhanced formic acid production for CO₂ photocatalytic reduction over Pd/H-TiO₂ catalyst

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FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING 2024年第11期18卷 134-134页

作者： Gao, Huimin Zhang, Jinpeng Zhang, Fangyuan jing, Jieying Li, Wen-ying Taiyuan Univ Technol State Key Lab Clean & Efficient Coal Utilizat Taiyuan 030024 Peoples R China Shanxi Zheda Inst Adv Mat & Chem Engn Taiyuan 030000 Shanxi Peoples R China

The photocatalytic reduction of CO2 into formic acid is a feasible approach to alleviate the effects of global climate change and achieve chemical energy storage. It is important to design highly active photocatalysts to improve the selectivity and yield of formic acid. In this study, TiO2-based catalysts were prepared and loaded with Pd nanoparticles via an impregnation process. The Pd/H-TiO2 catalyst demonstrated superior CO2 reduction activity and a high formic acid production rate of 14.14 mmol(cat)g(-1)h(-1). The excellent catalytic performance observed in the presence of a Pd/H-TiO2 catalyst is ascribed to the synergy between O-v and Pd. The presence of O-v led to increase in CO2 adsorption while Pd loading enhanced the photogenerated electron-hole pair separation. Electron transfer from H-TiO2 to Pd also contributed to CO2 activation.

关键词： CO2 reduction formic acid photocatalysis TiO2 catalyst

Characterization of the adsorption behavior of aqueous cadmium on nanozero-valent iron based on orthogonal experiment and surface complexation modeling

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1270-1274页

作者： Dongmei Liu Huan Tang ying Zhao Fuyi Cui jing Lu State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology School of Municipal and Environmental Engineering Harbin Institute of Technology

Polyvinylpyrrolidone K-30(PVP) was introduced into the preparation of nanozero-valent iron(n ZVI) and the traditional liquid-phase reduction was improved. The introduction of PVP simplified the traditional *** n ZVI prepared with this new approach showed excellent surface characters and high performance on the removal of cadmium. TEM results showed that the aggregates of n ZVI can reach to several micrometers in length but less than 100 nm in diameter. The iron particles that were enclosed by a layer of oxide film that is less than10 nm, demonstrated that the n ZVI possesses a core–shell structure. BET results indicate that the specific surface area of the n ZVI was 20.3159 m^2g^(-1). A three factor and three level orthogonal experiment was employed to find out the dominant factor that affects the removal rate of cadmium by n ZVI. Based on the range values, the prominence order of each factor was: initial p H of the solution N initial concentration of cadmium N dosage of n ZVI, the range was 96.453, 3.294 and 1.747, respectively. A simulation was performed under the same condition and a same conclusion was derived, this consistence confirmed the validity of the conclusion that p H is the most significant factor that affects the adsorption efficiency.

关键词： Cadmium Nanozero-valent iron Synthesis Polyvinylpyrrolidone Orthogonal experiment Diffuse layer model