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20篇 您的检索式:作者名="Shiwei Cheng"
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12018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents显示文摘Syncope belongs to the transient loss of consciousness(TLOC), characterized by a rapid onset, short duration, and spontaneous complete recovery. It is common in children and adolescents, accounting for 1% to 2% of emergency department visits.Recurrent syncope can seriously affect children's physical and mental health, learning ability and quality of life and sometimes cardiac syncope even poses a risk of sudden death. The present guideline for the diagnosis and treatment of syncope in children and adolescents was developed for guiding a better clinical management of pediatric syncope. Based on the globally recent development and the evidence-based data in China, 2018 Chinese Pediatric Cardiology Society(CPCS) guideline for diagnosis and treatment of syncope in children and adolescents was jointly prepared by the Pediatric Cardiology Society, Chinese Pediatric Society, Chinese Medical Association(CMA)/Committee on Pediatric Syncope, Pediatricians Branch, Chinese Medical Doctor Association(CMDA)/Committee on Pediatric Cardiology, Chinese College of Cardiovascular Physicians, Chinese Medical Doctor Association(CMDA)/Pediatric Cardiology Society, Beijing Pediatric Society, Beijing Medical Association(BMA). The present guideline includes the underlying diseases of syncope in children and adolescents, the diagnostic procedures, methodology and clinical significance of standing test and headup tilt test, the clinical diagnosis vasovagal syncope, postural orthostatic tachycardia syndrome, orthostatic hypotension and orthostatic hypertension, and the treatment of syncope as well as follow-up.Cheng Wang Yaqi Li Ying Liao Hong Tian Min Huang Xiangyu Dong Lin Shi Jinghui Sun Hongfang Jin Junbao Du Jindou An Jie Chen Mingwu Chen Qi Chen Sun Chen Yonghong Chen Zhi Chen Adolphus Kai-tung Chau Junbao Du Zhongdong Du Junkai Duan Hongyu Duan Xiangyu Dong Lin Feng Lijun Fu Fangqi Gong Yonghao Gui Ling Han Zhenhui Han Bing He Zhixu He Xiufen Hu Yimin Hua Guoying Huang Min Huang Ping Huang Yujuan Huang Hongfang Jin Mei Jin Bo Li Fen Li Tao Li Xiaohui Li Xiaoyan Liu Yan Li Haitao Lv Tiewei Lv Zipu Li Luyi Ma Silin Pan Yusheng Pang Hua Peng Yuming Qin Jie Shen Lin Shi Kun Sun Jinghui Sun Hong Tian Jie Tian Cheng Wang Hong Wang Lei Wang Jinju Wang Wendi Wang Yuli Wang Rongzhou Wu Tianhe Xia Yanyan Xiao Chunhong Xie Yanlin Xing Zhenyu Xiong Baoyuan Xu Yi Xu Hui Yan Shiwei Yang Qijian Yi Xia Yu Xianyi Yu Yue Yuan Hongyan Zhang Huili Zhang Li Zhang Qingyou Zhang Xi Zhang Yanmin Zhang Zhiwei Zhang Cuifen Zhao Bin Zhou Hua Zhu 2018Science Bulletin2018,63,23:54
2Non-Darcy flow in oil accumulation (oil displacing water) and relative permeability and oil saturation characteristics of low-permeability sandstones显示文摘Hydrocarbon resources in low-permeability sandstones are very abundant and are extensively distributed. Low-permeability reservoirs show several unique characteristics,including lack of a defi nite trap boundary or caprock,limited buoyancy effect,complex oil-gas-water distribution,without obvious oil-gas-water interfaces,and relatively low oil(gas) saturation. Based on the simulation experiments of oil accumulation in low-permeability sandstone(oil displacing water) ,we study the migration and accumulation characteristics of non-Darcy oil flow,and discuss the values and influencing factors of relative permeability which is a key parameter characterizing oil migration and accumulation in low-permeability sandstone. The results indicate that:1) Oil migration(oil displacing water) in lowpermeability sandstone shows non-Darcy percolation characteristics,and there is a threshold pressure gradient during oil migration and accumulation,which has a good negative correlation with permeability and apparent fluidity;2) With decrease of permeability and apparent fluidity and increase of fluid viscosity,the percolation curve is closer to the pressure gradient axis and the threshold pressure gradient increases. When the apparent fluidity is more than 1.0,the percolation curve shows modifi ed Darcy flow characteristics,while when the apparent fluidity is less than 1.0,the percolation curve is a 'concaveup' non-Darcy percolation curve;3) Oil-water two-phase relative permeability is affected by core permeability,fluid viscosity,apparent fluidity,and injection drive force;4) The oil saturation of lowpermeability sandstone reservoirs is mostly within 35%-60%,and the oil saturation also has a good positive correlation with the permeability and apparent fluidity.Zeng Jianhui Cheng Shiwei Kong Xu Guo Kai Wang Hongyu 2010Petroleum Science2010,7,1:11
3The heterogeneity of islet autoantibodies and the progression of islet failure in type 1 diabetic patients显示文摘Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobin A1 c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1 DM patients(duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1 DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus.Jin Liu Lingling Bian Li Ji Yang Chen Heng Chen Yong Gu Bingqin Ma Wei Gu Xinyu Xu Yun Shi Jian Wang Dalong Zhu Zilin Sun Jianhua Ma Hui Jin Xing Shi Heng Miao Bing Xin Yan Zhu Zhenwen Zhang Ruifang Bu Lan Xu Guangde Shi Wei Tang Wei Li Dongmei Zhou Jun Liang Xingbo Cheng Bimin Shi Jixiang Dong Ji Hu Chen Fang Shao Zhong Weinan Yu Weiping Lu Chenguang Wu Li Qian Jiancheng Yu Jialin Gao Xiaoqiang Fei Qingqing Zhang Xueqin Wang Shiwei Cui Jinluo Cheng Ning Xu Guofeng Wang Guoqing Han Chunrong Xu Yun Xie Minmin An Wei Zhang Zhixiao Wang Yun Cai Qi Fu Yu Fu Shuai Zheng Fan Yang Qingfang Hu Hao Dai Yu Jin Zheng Zhang Kuanfeng Xu Yifan Li Jie Shen Hongwen Zhou Wei He Xuqin Zheng Xiao Han Liping Yu Jinxiong She Mei Zhang Tao Yang 2016Science China(Life Sciences)2016,59,9:5
4Mesh Smoothing Method Based on Local Wave Analysis显示文摘As the mesh models usually contain noise data,it is necessary to eliminate the noises and smooth the mesh.But existed methods always lose geometric features during the smoothing process.Hence,the noise is considered as a kind of random signal with high frequency,and then the mesh model smoothing is operated with signal processing theory.Local wave analysis is used to deal with geometric signal,and then a novel mesh smoothing method based on the local wave is proposed.The proposed method includes following steps:Firstly,analyze the principle of local wave decomposition for 1D signal,and expand it to 2D signal and 3D spherical surface signal processing;Secondly,map the mesh to the spherical surface with parameterization,resample the spherical mesh and decompose the spherical signals by local wave analysis;Thirdly,propose the coordinate smoothing and radical radius smoothing methods,the former filters the mesh points' coordinates by local wave,and the latter filters the radical radius from their geometric center to mesh points by local wave;Finally,remove the high-frequency component of spherical signal,and obtain the smooth mesh model with inversely mapping from the spherical signal.Several mesh models with Gaussian noise are processed by local wave based method and other compared methods.The results show that local wave based method can obtain better smoothing performance,and reserve more original geometric features at the same time.QIN Xujia ZHENG Hongbo CHENG Shiwei LIU Shishuang XU Xiaogang 2012Chinese Journal of Mechanical Engineering2012,25,3:2
5High-level production penicillin G acylase from Alcaligenes faecalis in recombinant Escherichia coli with optimization of carbon sources显示文摘Cheng Shiwei Song Qingxu Wei Dongzi 2007Enzyme Microb Tecbnol2007,41,:1
6Endocrine pheromones couple fat rationing to dauer diapause through HNF4αnuclear receptors显示文摘Developmental diapause is a widespread strategy for animals to survive seasonal starvation and environmental harshness.Diapaused animals often ration body fat to generate a basal level of energy for enduring survival.How diapause and fat rationing are coupled,however,is poorly understood.The nematode Caenorhabditis elegans excretes pheromones to the environment to induce a diapause form called dauer larva.Through saturated forward genetic screens and CRISPR knockout,we found that dauer pheromones feed back to repress the transcription of ACOX-3,MAOC-1,DHS-28,DAF-22(peroxisomalβ-oxidation enzymes dually involved in pheromone synthesis and fat burning),ALH-4(aldehyde dehydrogenase for pheromone synthesis),PRX-10 and PRX-11(peroxisome assembly and proliferation factors).Dysfunction of these pheromone enzymes and factors relieves the repression.Surprisingly,transcription is repressed not by pheromones excreted but by pheromones endogenous to each animal.The endogenous pheromones regulate the nuclear translocation of HNF4αfamily nuclear receptor NHR-79 and its co-receptor NHR-49,and,repress transcription through the two receptors.The feedback repression maintains pheromone homeostasis,increases fat storage,decreases fat burning,and prolongs dauer lifespan.Thus,the exocrine dauer pheromones possess an unexpected endocrine function to mediate a peroxisome-nucleus crosstalk,coupling dauer diapause to fat rationing.Cheng Gao Qi Li Jialei Yu Shiwei Li Qingpo Cui Xiao Hu Lifeng Chen Shaobing O.Zhang 2021Science China(Life Sciences)2021,64,12:1
7Adaptive navigation assistance based on eye movement features in virtual reality显示文摘Background Navigation assistance is essential for users when roaming virtual reality scenes;however,the traditional navigation method requires users to manually request a map for viewing,which leads to low immersion and poor user experience.Methods To address this issue,we first collected data on who required navigation assistance in a virtual reality environment,including various eye movement features,such as gaze fixation,pupil size,and gaze angle.Subsequently,we used the boosting-based XGBoost algorithm to train a prediction model and finally used it to predict whether users require navigation assistance in a roaming task.Results After evaluating the performance of the model,the accuracy,precision,recall,and F1-score of our model reached approximately 95%.In addition,by applying the model to a virtual reality scene,an adaptive navigation assistance system based on the real-time eye movement data of the user was implemented.Conclusions Compared with traditional navigation assistance methods,our new adaptive navigation assistance method could enable the user to be more immersive and effective while roaming in a virtual reality(VR)environment.Song ZHAO Shiwei CHENG 2023Virtual Reality & Intelligent Hardware2023,5,3:1
8Extraction of Alpha transmitter signals from single-station observations using the direction-finding method显示文摘For the applications of Alpha very-low-frequency(VLF) systems consisting of multiple transmitters, determining the origin transmitter station of received signals is a crucial problem. Based on single-station observations, this study develops a directionfinding method to extract Russian Alpha transmitter signals. First, the amplitudes of Alpha signals received in Suizhou City,Hubei Province(31.57°N, 113.32°E) in the east-west(EW) and north-south(NS) directions are obtained by the power spectrum method. The amplitude ratios of signals in the two directions are subsequently adopted to estimate the propagation angles of the signals with respect to the NS direction of the VLF receiver station. Phase ambiguity in our system is eliminated by comparing Alpha signal waveform with that from the VTX transmitter in India(8.39°N, 77.75°E) as a reference station. Finally, we can determine the quadrant where the incoming wave signals are located relative to the receiver and eventually distinguish the exact Alpha transmitters. Based on the direction-finding results, the amplitudes of each Alpha signal are extracted, and their diurnal variation features are analyzed to verify the performance of our method. These results are of great significance for the further study of Alpha signals and VLF long-distance communication.GU XuDong CHEN Huan WANG ShiWei LU ZiLong NI BinBin LI GuangJian CHENG Wen 2022Science China(Technological Sciences)2022,65,8:1
9Association between TLR2 , MTR , MTRR , XPC , TP73 , TP53 genetic polymorphisms and gastric cancer: A meta-analysis显示文摘Chen Cheng Wang Lingyan Huang Yi Zhang Cheng Ye Huadan Xu Xuting Xu Leiting Ye Meng Duan Shiwei 2014Clinics and Research in Hepatology and Gastroenterology2014,,:1
10Production of enantiomerically pure(S)-β-phenylalanineand(R)-β-phenyl-alanine by penicillin G acylase from Escherichia coli in aqueous medium显示文摘Dengchao Li Shiwei Cheng Dongzhi Wei 2007Biotechnology Letters2007,29,12:1
11High-level production penicillin G acylase from Alcaligenes fae- calls in recombinant Escherichia coli with optimization carbon sources 显示文摘Cheng Shiwei Song Qingxun Wei Dongzhi 2007Enzyme and microbial Technology2007,41,3:1
12Optimization of Empty Pallets Dispatching Based on Different Transportation Modes显示文摘In the pallet pool system, the differentiation of palletized freight volumes in different regions and seasonal transport of certain goods lead to the imbalance of pallets distribution among regions. It is necessary to improve the utilization of pallets through dispatching. The paper analyzes the factors which affect empty pallets dispatching, it includes carbon emission, transportation time and pallet type based on the pallet pool mode of enterprise alliance. On this basis, the optimization model is established with the goal of minimum total dispatching cost. Then, according to the different influences of railway and highway in transportation cost, the dispatching scheme is analyzed and the transportation mode of empty pallets dispatching is determined. Considering the characteristics of model, Cplex is used to solve it. Finally, a case is used to verify the feasibility and superiority of reasonable empty pallets dispatching in different transportation modes, and the transport characteristics of two transportation modes are analyzed. Moreover, the costs of pallets leasing and dispatching are compared.Kang ZHOU Shiwei HE Rui SONG Weichuan YIN Lingyan CHENG 2017Journal of Systems Science and Information2017,8,2:1
13EasyGaze:Hybrid eye tracking approach for handheld mobile devices显示文摘Background Eye-tracking technology for mobile devices has made significant progress.However,owing to limited computing capacity and the complexity of context,the conventional image feature-based technology cannot extract features accurately,thus affecting the performance.Methods This study proposes a novel approach by combining appearance-and feature-based eye-tracking methods.Face and eye region detections were conducted to obtain features that were used as inputs to the appearance model to detect the feature points.The feature points were used to generate feature vectors,such as corner center-pupil center,by which the gaze fixation coordinates were calculated.Results To obtain feature vectors with the best performance,we compared different vectors under different image resolution and illumination conditions,and the results indicated that the average gaze fixation accuracy was achieved at a visual angle of 1.93°when the image resolution was 96×48 pixels,with light sources illuminating from the front of the eye.Conclusions Compared with the current methods,our method improved the accuracy of gaze fixation and it was more usable.Shiwei CHENG Qiufeng PING Jialing WANG Yijian CHEN 2022Virtual Reality & Intelligent Hardware2022,4,2:1
14Reading comprehension based on visualization of eye tracking and EEG data显示文摘Using eye tracking technology can help us understand reading behavior.Furthermore,sharing the teacher’s eye tracking features resulted in improving the students’comprehension of the same reading material[1].On the other hand,a user’s intention can be analyzed by physiological data,such as electroencephalogram(EEG)[2].Shiwei CHENG Yilin HU Jing FAN Qianjing WEI 2020Science China(Information Sciences)2020,63,11:1
15Production of enantiomerically pure (S)-β-phenylalanine and (R)-β-phenylalanine by penicillin G acylase from Escherichia coli in aqueous medium显示文摘Li Dengchao Cheng Shiwei Wei Dongzhi 2007Biotechnol Lett2007,29,:1
16Collaborative eye tracking based code review through real-time shared gaze visualization显示文摘Code review is intended to find bugs in early development phases,improving code quality for later integration and testing.However,due to the lack of experience with algorithm design,or software development,individual novice programmers face challenges while reviewing code.In this paper,we utilize collaborative eye tracking to record the gaze data from multiple reviewers,and share the gaze visualization among them during the code review process.The visualizations,such as borders highlighting current reviewed code lines,transition lines connecting related reviewed code lines,reveal the visual attention about program functions that can facilitate understanding and bug tracing.This can help novice reviewers to make sense to confirm the potential bugs or avoid repeated reviewing of code,and potentially even help to improve reviewing skills.We built a prototype system,and conducted a user study with paired reviewers.The results showed that the shared real-time visualization allowed the reviewers to find bugs more efficiently.Shiwei CHENG Jialing WANG Xiaoquan SHEN Yijian CHEN Anind DEY 2022Frontiers of Computer Science2022,16,3:0
17GSTAR:an innovative software platform for processing space geodetic data at the observation level显示文摘To meet the demands for the data combination with multiple space geodetic techniques at the observation level,we developed a new software platform with high extensibility and computation efficiency,named space Geodetic SpatioTemporal data Analysis and Research software(GSTAR).Most of the modules in the GSTAR are coded in C++with object-oriented programming.The layered modular theory is adopted for the design of the software,and the antenna-based data architecture is proposed for users to construct personalized geodetic application scenarios easily.The initial performance of the GSTAR software is evaluated by processing the Global Navigation Satellite System(GNSS)data collected from 315 globally distributed stations over two and a half years.The accuracy of GNSS-based geodetic products is evaluated by comparing them with those released by International GNSS Service(IGS)Analysis Centers(AC).Taking the products released by European Space Agency(ESA)as reference,the Three-Dimension(3D)Root-Mean-Squares(RMS)of the orbit differences are 2.7/6.7/3.3/7.7/21.0 cm and the STandard Deviations(STD)of the clock differences are 19/48/16/32/25 ps for Global Positioning System(GPS),GLObal NAvigation Satellite System(GLONASS),Galileo navigation satellite system(Galileo),BeiDou Navigation Satellite System(BDS),Medium Earth Orbit(MEO),and BDS Inclined Geo-Synchronous Orbit(IGSO)satellites,respectively.The mean values of the X and Y components of the polar coordinate and the Length of Day(LOD)with respect to the International Earth Rotation and Reference Systems Service(IERS)14 C04 products are-17.6 microarc-second(μas),9.2μas,and 14.0μs/d.Compared to the IGS daily solution,the RMSs of the site position differences in the north/east/up direction are 1.6/1.5/3.9,3.8/2.4/7.6,2.5/2.4/7.9 and 2.7/2.3/7.4 mm for GPS-only,GLONASS-only,Galileo-only,and BDS-only solution,respectively.The RMSs of the differences of the tropospheric Zenith Path Delay(ZPD),the north gradients,and the east gradients are 5.8,0.9,and 0.9 mm with respect to the IGS products.The X and Y components of the geocenter motion estimated from GPS-only,Galileo-only,and BDS-only observations well agree with IGS products,while the Z component values are much nosier where anomalous harmonics in GNSS draconitic year can be found.The accuracies of the above products calculated by the GSTAR are comparable with those from different IGS ACs.Compared to the precise scientific orbit products,the 3D RMS of the orbit differences for the two Gravity Recovery and Climate Experiment Follow-on(GRACE-FO)satellites is below 1.5 cm by conducting Precise Point Positioning with Ambiguity Resolution(PPP-AR).In addition,a series of rapid data processing algorithms are developed,and the operation speed of the GSTAR software is 5.6 times faster than that of the Positioning and Navigation Data Analyst(PANDA)software for the quad-system precise orbit determination procedure.Chuang Shi Shiwei Guo Lei Fan Shengfeng Gu Xinqi Fang Linghao Zhou Tao Zhang Zhen Li Min Li Wenwen Li Cheng Wang Yidong Lou 2023Satellite Navigation2023,4,3:0
18HPMA modified aluminium nitride powder for aqueous tape casting of AlN ceramic substrates显示文摘Aluminum nitride(AlN)is considered one of the most desirable materials for integrated circuits and electronic packaging substrates.However,raw AlN powder reacts easily with water,forming Al(OH)3 or AlOOH on the surface and hindering the development of an aqueous tape-casting process for preparing AlN ceramic substrates.In this study,hydrolyzed polymaleic anhydride(HPMA)was used to modify AlN powder,which has good water solubility and dispersibility.The AlN powder was modified with 5 wt%HPMA remained stable in water for at least 90 h under magnetic stirring condition and 24 h under ball milling condition,indicating that HPMA-modified AlN powder has good resistance to hydrolysis.The action mechanism of HPMA is revealed.Firstly,–COOH of the HPMA polymer and the oxide layer on the surface of the AlN powder underwent a dehydration condensation reaction to form a compound.Secondly,long chains of the polymer further coated the surface of the AlN powder,forming an anti-hydration layer with a thickness of about 7.0 nm on the surface of the AlN particles.In addition,AlN green sheets were successfully prepared by aqueous tape casting using the HPMA-modified AlN powder without additional dispersants.Subsequently,AlN ceramic substrates were obtained by sintering at 1750℃for 4 h under an N2 atmosphere with a pressure of 0.2 MPa.The relative density and thermal conductivity were tested to be 97.3%and 122 W/(m·K),respectively.Meng Li Jianping Ai Zhengjuan Wang Zhenhai Xue Lihong Cheng Guohong Zhou Shiwei Wang 2023Journal of Advanced Ceramics2023,12,9:0
19A Bionic Stick–Slip Piezo-Driven Positioning Platform Designed by Imitating the Structure and Movement of the Crab显示文摘By imitating the body structure and movement mode of the crab in nature,a novel stick–slip piezo-driven positioning platform was proposed by employing the bionic flexible hinge mechanism with a symmetrical structure and two piezoelectric stacks.The structural design and bionic motion principle were discussed,followed by analyzing the feasibility,safety,and output magnification ratio of the bionic flexible hinge mechanism via the stiffness matrix method and finite element simulation.To investigate the output performances of the positioning platform,a prototype was fabricated and an experiment system was established.Stepping characteristics of the positioning platform under various driving voltages were characterized,and the results indicated that the positioning platform could move steadily under various driving voltages.Within 1 s,the differences between the forward and reverse output displacement were less than 3%under different driving frequencies,proving the high bidirectional motion symmetry.The maximum driving speed of 5.44 mm/s was obtained under the driving voltage of 120 V and driving frequency of 5 Hz.In addition,the carrying load capacity of the positioning platform was tested by standard weights,and the results showed that when the carrying load reached 10 N,the driving speed could still reach 60μm/s.Zhixin Yang Xuan Li Jinyan Tang Hu Huang Hongwei Zhao Yiming Cheng Shiwei Liu Chunyu Li Maoji Xiong 2023Journal of Bionic Engineering2023,20,6:0
20Reduced blister quantity in damaged tungsten exposed to deuterium plasma显示文摘Tungsten (W) is a promising candidate for plasma-facing materials (PFMs) in fusion reactors owing to its excellent thermal conductivity, sputtering resistance, and low hydrogen isotope solubility [1]. W PFMs encounter the challenges of triple irradiations generated by high-heat loads;high-flux particles, including helium/deuterium (D)/tritium (T);and high-energy neutrons.Xiu-Li Zhu Long Cheng ShiWei Wang Yue Yuan Guang-Hong Lu Ying Zhang Er-Yang Lu Xing-Zhong Cao Jian-Jun Huang 2019Science China(Physics,Mechanics & Astronomy)2019,62,5:0
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