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| 1 | Mechanical Properties Prediction of the Mechanical Clinching Joints Based on Genetic Algorithm and BP Neural Network显示文摘For optimal design of mechanical clinching steel-aluminum joints, the back propagation(BP) neural network is used to research the mapping relationship between joining technique parameters including sheet thickness, sheet hardness, joint bottom diameter etc., and mechanical properties of shearing and peeling in order to investigate joining technology between various material plates in the steel-aluminum hybrid structure car body.Genetic algorithm(GA) is adopted to optimize the back-propagation neural network connection weights.The training and validating samples are made by the BTM? Tog-L-Loc system with different technologic parameters.The training samples' parameters and the corresponding joints' mechanical properties are supplied to the artificial neural network(ANN) for training.The validating samples' experimental data is used for checking up the prediction outputs.The calculation results show that GA can improve the model's prediction precision and generalization ability of BP neural network.The comparative analysis between the experimental data and the prediction outputs shows that ANN prediction models after training can effectively predict the mechanical properties of mechanical clinching joints and prove the feasibility and reliability of the intelligent neural networks system when used in the mechanical properties prediction of mechanical clinching joints.The prediction results can be used for a reference in the design of mechanical clinching steel-aluminum joints. | LONG Jiangqi LAN Fengchong CHEN Jiqing YU Ping | 2009 | Chinese Journal of Mechanical Engineering2009，22，1： | 22 |
| 2 | Synthesis of well-defined Fe3O4 nanorods/N-doped graphene for lithium-ion batteries显示文摘磁性的 nanoparticles 的几何尺寸和分发对 graphene (GN ) 的形态学批评 nanocomposites,并且当这些 composites 在锂离子电池(解放) 被用作阳极材料时,因此,他们能影响能力和骑车的性能。在这个工作, Fe 3 O 4 nanorods 在二步,一个热水的过程和一个退火的过程从一位二进制先锋被扔到充分扩大的做氮的 GN 表上。这条线路有效地调节了 Fe 3 O 4 nanorod 尺寸分发并且阻止了他们的聚集。二进制先锋的转变被 X 光检查衍射(XRD ) 描绘, Fourier 变换红外线(FTIR ) 光谱学, X 光检查光电子光谱学(XPS ) , thermogravimetric 分析(TGA ) ,和传播电子显微镜学(TEM ) 。XPS 分析显示了做 N 的 GN 表的存在,并且磁性的 nanocrystals 在弄平的做 N 的 GN 表的表面上被抛锚并且一致地散布了。作为高效阳极材料,结构为电子运输和交换是有益的,吗导致 929 妈頿酎鯺?的一个大可逆能力?钱醨?鎓?鑟醫???钳????頿铭????龜鴿????讵??徬?讂?疞???鐿?鯷鳅?醛???讬????锿???魝??螮?箖徬吗?? | Jiqing Jiao Wenda Qiu Jianguo Tang Liuping Chen Laiying Jing | 2016 | Nano Research2016，9，5： | 18 |
| 3 | Performance analysis for range expansion in heterogeneous networks显示文摘In this paper,the uplink and downlink performance of a two tier heterogeneous network(HetNet)with range expansion(RE)is analyzed.Different from previous works,base stations(BSs)are modeled as a spatial Poisson point process.This model can not only capture the irregularity of the BS deployment but also lead to closed form expressions.With the analytical results,the impacts of several key parameters on the coverage and throughput performance are investigated.Our results justifies the effectiveness of RE and Pico deployment.Based on our analyses,certain attention should be made on the RE design to balance the uplink and downlink performance.Our analyses are corroborated by simulations and can thus serve as a flexible and quick guidance for system design without complicated and time consuming system level platform construction and simulation. | FEI ZeSong DING HaiChuan XING ChengWen NI JiQing KUANG JingMing | 2014 | Science China(Information Sciences)2014，57，8： | 11 |
| 4 | Convolutional neural networks for expert recommendation in community question answering显示文摘Community Question Answering(CQA) is becoming an increasingly important web service for people to search for expertise and to share their own. With lots of questions being solved, CQA have built a massive, freely accessible knowledge repository, which can provide valuable information for the broader society rather than just satisfy the question askers. It is critically important for CQA services to get high quality answers in order to maximize the benefit of this process. However, people are considered as experts only in their own specialized areas. This paper is concerned with the problem of expert recommendation for a newly posed question, which will reduce the questioner's waiting time and improve the quality of the answer, so as to improve the satisfaction of the whole community. We propose an approach based on convolutional neural networks(CNN) to resolve this issue. Experimental analysis over a large real-world dataset from Stack Overflow demonstrates that our approach achieves a significant improvement over several baseline methods. | Jian WANG Jiqing SUN Hongfei LIN Hualei DONG Shaowu ZHANG | 2017 | Science China(Information Sciences)2017，60，11： | 11 |
| 5 | Angular response of ‘pin-hole' imaging structure measured by collimated β source显示文摘The pitch-angle distribution of energetic particles is important for space physics studies on magnetic storm and particle acceleration.A‘pin-hole’imaging structure is built with the‘pin-hole’technique and a position sensitive detector,which can be used to measure the pitch angle distribution of energetic particles.To calibrate the angular response of the‘pin-hole’imaging structure,special experiment facilities are needed,such as the particle accelerator with special design.The features of this kind of particle accelerator are:1)The energy range of the outgoing particles should be mid-energy particles(tens keV to several hundred keV);2)the particle flux should be consistent in time-scale;3)the directions of the outgoing particles should be the same and 4)the particle number within the spot should be low enough.In this paper,a method to calibrate the angular response of the‘pin-hole’imaging structure by the90Sr/90Y β source with a collimator is introduced and simulated by Geant4 software.The result of the calibration with the collimated β source is in accord with the Geant4 simulations,which verifies the validity of this method. | ZOU Hong LUO Lin LI ChenFang JIA XiangHong XU Feng CHEN HongFei CHEN Jiang SHI WeiHong YU XiangQian ZOU JiQing | 2013 | Science China(Technological Sciences)2013，56，11： | 10 |
| 6 | Experimental Study on Occupant's Thermal Responses under the Non-uniform Conditions in Vehicle Cabin during the Heating Period显示文摘The existing investigations on thermal comfort mostly focus on the thermal environment conditions, especially of the air-flow field and the temperature distributions in vehicle cabin. Less attention appears to direct to the thermal comfort or thermal sensation of occupants, even to the relationship between thermal conditions and thermal sensation. In this paper, a series of experiments were designed and conducted for understanding the non-uniform conditions and the occupant's thermal responses in vehicle cabin during the heating period. To accurately assess the transient temperature distribution in cabin in common daily condition, the air temperature at a number of positions is measured in a full size vehicle cabin under natural winter environment in South China by using a discrete thermocouples network. The occupant body is divided into nine segments, the skin temperature at each segment and the occupant's local thermal sensation at the head, body, upper limb and lower limb are monitored continuously. The skin temperature is observed by using a discrete thermocouples network, and the local thermal sensation is evaluated by using a seven-point thermal comfort survey questionnaire proposed by American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc(ASHRAE) Standard. The relationship between the skin temperature and the thermal sensation is discussed and regressed by statistics method. The results show that the interior air temperature is highly non-uniform over the vehicle cabin. The locations where the occupants sit have a significant effect on the occupant's thermal responses, including the skin temperature and the thermal sensation. The skin temperature and thermal sensation are quite different between body segments due to the effect of non-uniform conditions, clothing resistance, and the human thermal regulating system. A quantitative relationship between the thermal sensation and the skin temperature at each body segment of occupant in real life traffic is presented. The investigation result indicates that the skin temperature is a robust index to evaluate the thermal sensation. Applying the skin temperature to designing and controlling parameters of the heating, ventilation and air conditioning(HVAC) system may benefit the thermal comfort and reducing energy consumption. | ZHANG Wencan CHEN Jiqing LAN Fengchong | 2014 | Chinese Journal of Mechanical Engineering2014，27，2： | 8 |
| 7 | Pd/AlF3 Catalysts for Catalytic Dehydrofluorination of 1,1,1,3,3-Pentafluoropropane显示文摘 | WANG Fang ZHANG Wenxia LIANG Yan WANG Yuejuan LU Jiqing LUO Mengfei | 2015 | Chemical Research in Chinese Universities2015，31，6： | 8 |
| 8 | Ergodic secrecy rate of two-user MISO interference channels with statistical CSI显示文摘This paper considers a two-user multiple-input single-output(MISO) interference channel with confidential messages(IFC-CM), where the beamforming vectors at the two transmitters are jointly optimized using the closed-form Pareto-optimal parameterization. We prove that artificial noise cannot improve the secrecy rate performance, and coordinated beamforming is secrecy-rate optimal which is achieved by agreeing on the parameters between the two transmitters. We analyze the feasible set of the beamforming parameters that guarantees positiveness of the secrecy rates when the transmitters know only statistical CSI, and then analysis in the ergodic secrecy rate region is discussed. More importantly, we derive the closed form of the ergodic secrecy rates and illustrate the Pareto-optimal structure of the beamforming vectors. | FEI ZeSong NI JiQing ZHAO Di XING ChengWen WANG NiWei KUANG JingMing | 2014 | Science China(Information Sciences)2014，57，10： | 7 |
| 9 | Influence of plastic film mulching and planting density on yield,leaf anatomy,and root characteristics of maize on the Loess Plateau显示文摘In rainfed areas of northwestern China,maize production is constrained mainly by low temperature during early growth and water limitation during the entire growth period.Plastic film mulching is commonly used to increase maize yield in this area,because it increases topsoil temperature and moisture content as well as water use efficiency.However,the physiological and anatomical bases of maize yield improvement with plastic film mulching are not well understood.The effects of plastic film mulching and planting density on maize yield,photosynthetic characteristics,respiration,leaf anatomy,and root growth were studied in a two-year field experiment conducted on the Loess Plateau of China in 2017 and 2018.The experiment used a split-split plot design with two mulching treatments(plastic film mulching and no mulching),two planting densities(7.5×104 and10.5×104 plants ha-1),and two maize cultivars,Zhengdan 958 and Xianyu 335.Compared with no mulching,plastic film mulching increased maize yields by 31.1%–46.4%in 2017 and3.6%–34.7%in 2018.Compared with low planting density,high planting density significantly increased and slightly reduced yields of both cultivars in the dry year 2017 and the rainy year 2018,respectively.Plastic film mulching increased photosynthesis and respiration as well as leaf stomatal density and aperture.Photosynthetic rate,dark respiration,and stomatal conductance and aperture were lower at high planting than at low planting density.Maize yield was positively correlated with photosynthesis,dark respiration,and stomatal aperture.Mulching increased root dry weight and length in the 0–20 cm soil layer and root activity at maturity.Overall,the changes in root growth and leaf anatomy resulted in increased photosynthesis and dark respiration,and the increased photosynthesis contributed to the increase in grain yield and biomass production under plastic film mulching conditions.Our results increase understanding of the physiological mechanisms by which plastic film mulching increases maize yield in water-and temperature-limited areas. | Li Niu Yanyan Yan Peng Hou Wenbo Bai Rulang Zhao Yonghong Wang Shaokun Li Taisheng Du Ming Zhao Jiqing Song Wenbin Zhou | 2020 | The Crop Journal2020，8，4： | 6 |
| 10 | Control Algorithm of Electric Vehicle in Coasting Mode Based on Driving Feeling显示文摘Coasting in gear is a common driving mode for the conventional vehicle equipped with the internal combustion engine(ICE), and the assistant braking function of ICE is utilized to decelerate the vehicle in this mode. However, the electric vehicle(EV) does not have this feature in the coasting mode due to the relatively small inertia of the driving motor, so it will cause the driver cannot obtain the similar driving feeling to that of the conventional vehicle, and even a traffic accident may occur if the driver cannot immediately adapt to the changes. In this paper, the coasting control for EV is researched based on the driving feeling. A conventional vehicle equipped with continuously variable transmission(CVT) is taken as the reference vehicle, and the combined simulation model of EV is established based on AVL CRUISE and MATLAB/Simulink. The torque characteristic of the CVT output shaft is measured in coasting mode, and the data are smoothed and fitted to a polynomial curve. For the EV in coasting mode, if the state of charge(SOC) of the battery is below 95%, the polynomial curve is used as the control target for the torque characteristic of the driving motor, otherwise, the required torque is replaced by hydraulic braking torque to keep the same deceleration. The co-simulation of Matlab/Simulink/Stateflow and AVL CRUISE, as well as the hardware-in-loop experiment combined with d SPACE are carried out to verify the effectiveness and the real-time performance of the control algorithm. The results show that the EV with coasting braking control system has similar driving feeling to that of the reference vehicle, meanwhile, the battery SOC can be increased by 0.036% and 0.021% in the initial speed of 100 km/h and 50 km/h, respectively. The proposed control algorithm for EV is beneficial to improve the driving feeling in coasting mode, and it also makes the EV has the assistant braking function. | SUN Daxu LAN Fengchong ZHOU Yunjiao CHEN Jiqing | 2015 | Chinese Journal of Mechanical Engineering2015，28，3： | 5 |
| 11 | Melamine-assisted pyrolytic synthesis of bifunctional cobalt-based core–shell electrocatalysts for rechargeable zinc–air batteries显示文摘Designing a highly active-and stable non-noble metal bifunctional oxygen catalyst for rechargeable Znair battery remains a great challenge. Herein, we develop a facile and melamine-assisted-pyrolysis(MAP)strategy for the synthesis of core–shell Co-based electrocatalysts@N-doped carbon nanotubes(Co@CNTs)derived from metal–organic frameworks. The Co@CNTs exhibited excellent bifunctional electrocatalytic performance for both oxygen evolution and reduction. DFT calculations demonstrated that the Gibbs free energy of the rate-determining step was small enough to improve ORR activities. As a result, a Zn-air battery assembled with Co@CNTs proves a lager power density, low voltage gap between charge–discharge and excellent stability. Thus, this work offers a facile strategy to realize the synthesis of non-noble metal electrocatalyst for Zn-air battery materials with high electrochemical performance. | Jiqing Jiao Yuan Pan Bin Wang Wenjuan Yang Shoujie Liu Chao Zhang | 2021 | Journal of Energy Chemistry2021，30，2： | 5 |
| 12 | Imaging energetic electron spectrometer onboard a Chinese navigation satellite in the inclined GEO orbit显示文摘The energetic electron measurement is one of the most important issues to understand dynamics in space physics and the applications for space weather. In this study, the principle and functional components of the imaging energetic electron spectrometer(IES) onboard a Chinese navigation satellite in the inclined GEO orbit(IGSO) was introduced. The IES instrument is developed by the team in Peking University(BeiDa), thus it is named as BD-IES. Based on the pin-hole technique, the instrument can measure 50–600 keV electrons incident from 9 directions over a range of 180° in polar angle. With pulse height analysis(PHA), the spectrum can be determined for each direction. The energy and angular calibrations were performed, which show the good energy and angular characteristics of BD-IES. Monte Carlo simulations show that the anti-proton design of BDIES can effectively decrease the proton contamination on the electron measurements in the inclined GEO orbit. The primary results of BD-IES verify the successful design of this instrument. | ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei ZOU JiQing CHEN Jiang SHI WeiHong YU XiangQian ZHONG WeiYing WANG YongFu ZHOU XuZhi HAO YiXin CHEN XingRan JIA XiangHong XU Feng SHAO SiPei WANG Bo HAO XiaoYun ZHANG XiaoXin | 2018 | Science China(Technological Sciences)2018，61，12： | 5 |
| 13 | Partial Least Squares Based Total Variability Space Modeling for I-Vector Speaker Verification显示文摘As an effective and low-dimension representation for speech utterances with different lengths,i-vector method has drawn considerable attentions in speaker verification. Training a Total variability space(TVS) is one of the key parts in the i-vector method. However, the traditional training method only explores the relationship between different mean supervectors, ignoring priori category information of speakers, which results in a lack of discrimination. In the proposed method, a discriminative TVS based on Partial least squares(PLS) is estimated, in which both the correlation of intra-class and the distinction of inter-class are fully utilized due to using speaker labels, and the proposed method can achieve a better performance. | CHEN Chen HAN Jiqing | 2018 | Chinese Journal of Electronics2018，27，6： | 4 |
| 14 | Effects of Martian crustal magnetic field on its ionosphere显示文摘The effect of the Martian crustal magnetic field is one of the hot topics of the study of Martian ionosphere.The studies on this topic are summarized in this paper.Main data of the Martian ionosphere were resulted from radio occultation experiments.According to the observations,the electron density scale height and the peak electron density of the Martian ionosphere are influenced by its crustal magnetic field.The strong horizontal magnetic field prevents the vertical diffusion of the plasma and makes the electron density scale height in the topside ionosphere close to that in the photo equilibrium region.In the cusp-like regions with strong vertical magnetic field,the enhanced vertical diffusion leads to a larger electron density scale height in the diffusion equilibrium region.The observation of radio occultation experiment onboard Mars Global Surveyor (MGS) showed that the averaged peak electron density observed in the southern hemisphere with strong crustal magnetic field was slightly larger than that in the northern hemisphere with weak crustal magnetic field.The Mars advanced radar for subsurface and ionosphere sounding (MARSIS) onboard Mars Express (MEX) was the first topside sounder to be used to observe Martian ionosphere.The MARSIS results confirmed that the enhancement of the peak electron density occurred in cusp-like regions with open field lines,and the amount of the enhancement was much larger than that observed by the radio occultation experiment.There are two possible mechanisms for the peak electron density enhancement in the cusp-like crustal magnetic field regions:One is the precipitation of the energetic particles and the other is the heating by the waves excited by plasma instabilities.It's difficult to determine which one is the key mechanism for the peak electron density enhancement.Based on these studies,several interesting problems on the Martian ionosphere and plasma environment are presented. | ZOU Hong,CHEN HongFei,YU Ning,SHI WeiHong,YU XiangQian,ZOU JiQing & ZHONG WeiYing Institute of Space Physics and Applied Technology,Peking University,Beijing 100871,China | 2010 | Science China(Technological Sciences)2010，53，6： | 4 |
| 15 | Direct gas-phase epoxidation of propylene to propylene oxide using air as oxidant on supported gold catalyst显示文摘在 2-SiO2, 和 ZrO 2-SiO2 支持的 SiO 2, TiO 2, TiO 上支持的金催化剂被与 tetrachloroauric 酸的基本溶液使每支持妊娠准备。X 光检查衍射(XRD ) ,传播电子显微镜学(TEM ) ,和 X 光检查光电子光谱学(XPS ) 技术被用来描绘他们的结构和表面作文。结果显示金粒子的尺寸能被控制到在由准备的这个方法的 10 nm 下面。有水的洗的金催化剂能显著地在表面上提高金属性的金粒子的分散,但是它不能完全移开氯化物离子留在表面上。在这些催化剂上把空气用作氧化剂的丙烯的直接蒸汽阶段 epoxidation 的催化表演在气压被评估。到丙烯氧化物(PO ) 的选择被发现在溪流上与反应时间变化。以空气压力的反应条件,温度 325 ° C,喂煤气的比率 V (C 3 H 6)/V (O 2)=½
,和 GHSV = 6000 h −1, 有 0.9% 丙烯的 17.9% PO 选择变换被获得在起始为 Au/SiO 2 的 10 min 催化剂。在反应以后 60 min 8.9% 仅仅 PO 选择被检测,但是丙烯变换升起到 1.4% 并且主要产品被转移到丙烯醛(72% 选择) 。因为更小的金粒子被获得,有镁柠檬酸盐答案的洗的 Au/TiO 2-SiO2 和 Au/ZrO 2-SiO2 样品能显著地提高这项活动和 PO 选择。 | Zhanghuai Suo Mingshan Jin Jiqing Lu Zhaobin Wei Can Li | 2008 | Journal of Natural Gas Chemistry2008，17，2： | 4 |
| 16 | Cryptography on elliptic curves over p-adic number fields显示文摘In this paper we introduce a cryptosystem based on the quotient groups of the group of rational points of an elliptic curve defined over p-adic number field. Some additional parameters are taken in this system, which have an advantage in performing point multiplication while keeping the security of ECC over finite fields. We give a method to select generators of the cryptographic groups, and give a way to represent the elements of the quotient groups with finitely bounded storage by establishing a bijection between these elements and their approximate coordinates. The addition formula under this representation is also presented. | XU MaoZhi ZHAO ChunLai FENG Min REN ZhaoRong YE JiQing | 2008 | Science in China(Series F)2008，51，3： | 4 |
| 17 | Discussion on the geometric factor in the detection of high energy electrons in geospace显示文摘High energy electron is a kind of sources to be detected in the geospace environ- ment. Generally, the particle telescope with much thick semiconductor detector is used as the sensor for energetic electrons because they can penetrate deeply into the detector. The more energy of the electrons is, the deeper they can penetrate into, so that the geometric factor varies with energy of the incident electrons. We discuss the geometric factor of particle radiation detector (PRD), which is a payload on ZY-1 (CBERS-1 and CBERS-2) satellites to monitor the high energy particle ra- diation inside the satellites. According to the NASA’s AE8 model, the geometric factors of electrons for the low energy bin (0.5―1.0 MeV) and the high energy bin (> 2.0 MeV) are 2.468 and 1.736 cm2·sr, respectively. These results are much differ- ent from the traditional calculation of the geometric factor that is 1.18 cm2·sr. The angle-response function of the telescope is also derived, which can be useful for design of the telescope and analysis of the directional distribution. | CHEN HongFei SHI WeiHong ZOU Hong ZOU JiQing | 2008 | Science China(Technological Sciences)2008，51，1： | 3 |
| 18 | A primary study of the acoustics of Chinese traditional theatrical buildings显示文摘The traditional performing arts and theatrical buildings in China can be traced back to a long history and were well developed during Song and Yuan Dynasties, 11th-14th centuries. Pavilion stage, opened on three sides and thrusting into the audience area, was unique and the most popular form in the open-air theatres, the courtyard theatres, and the indoor theatres up to the present day. As the traditional Chinese opera is performed in an abstract way, no stage settings are required and used. Therefore, the pavilion stage including the flat or domed ceiling and the back wall is virtually functioned as a reflective shell, which increases the early reflections and also intensifies the sound in the audience area. Meanwhile, it provides sufficient self-support to the performers. Acoustical parameters including reverberation time RT, early decay time EDT, acoustic ratio C (50), strength index (loudness) G, and stage support factor ST1 were measured and reported on several traditional theatrical buildings. | WANG Jiqing (Institute of Acoustics, Tongji University, Shanghai 200092, China ) | 2003 | 声学技术2003，22，z1： | 3 |
| 19 | H7N9 virus infection triggers lethal cytokine storm by activating gasdermin E-mediated pyroptosis of lung alveolar epithelial cells显示文摘The H7N9 influenza virus emerged in China in 2013,causing more than 1560 human infections,39% of which were fatal.A ‘cytokine storm’ in the lungs of H7N9 patients has been linked to a poor prognosis and death;however,the underlying mechanism that triggers the cytokine storm is unknown.Here,we found that efficient replication of the H7N9 virus in mouse lungs activates gasdermin E(GSDME)-mediated pyroptosis in alveolar epithelial cells,and that the released cytosolic contents then trigger a cytokine storm.Knockout of Gsdme switched the manner of death of A549 and human primary alveolar epithelial cells from pyroptosis to apoptosis upon H7N9 virus infection,and Gsdme knockout mice survived H7N9 virus lethal infection.Our findings reveal that GSDME activation is a key and unique mechanism for the pulmonary cytokine storm and lethal outcome of H7N9 virus infection and thus opens a new door for the development of antivirals against the H7N9 virus. | Xiaopeng Wan Jiqing Li Yupeng Wang Xiaofei Yu Xijun He Jianzhong Shi Guohua Deng Xianying Zeng Guobin Tian Yanbing Li Yongping Jiang Yuntao Guan Chengjun Li Feng Shao Hualan Chen | 2022 | National Science Review2022，9，1： | 3 |
| 20 | The Study on the Ranks of Environment Emergency Response Activity Based on Weather Pattems显示文摘 | Jiqing Tan | 2013 | 遥感科学(中英文版)2013，1，1： | 2 |
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