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Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach
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作者 Duong Q.Nguyen Thinh D.Le +2 位作者 Phuong D.Nguyen Nga T.K.Le H.Nguyen-Xuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2197-2214,共18页
Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound seg... Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network.Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions.To achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the trainedmodels.The selectedmodel demonstrates exceptional segmentation performance for complex 3D facial wounds.Furthermore,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study.Our method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous method.From this result,we use 3D printing technology to illustrate the shape of the wound filling.The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design.By automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient outcomes.Additionally,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants.Our source code is available at https://github.com/SIMOGroup/WoundFilling3D. 展开更多
关键词 3D printing technology face reconstruction 3D segmentation 3D printed model
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Temporal and spatial differences in human activities performed in Urban Green Spaces of Vilnius(Lithuania)
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作者 Luís Valença Pinto Carla Sofia Santos Ferreira Paulo Pereira 《Geography and Sustainability》 CSCD 2024年第2期302-317,共16页
Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,... Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,weekly,and daily use of three urban green spaces(Vingis Park,Bernardino Garden,and Jomantas Park)in Vilnius(Lithuania).The study is based on an on-site observation-based survey,which recorded users’characteristics,activities,and weather conditions during summer and winter.The results showed that UGS’s seasonal,weekly,and daily use differed according to park and users’characteristics.Parks with a higher diversity of facilities had a high seasonal difference in the number of observed activities.User numbers were higher in the summer for activities with children,social activities,sports,and water activities than in the winter.Jomantas Park had the lowest variability in user characteristics.Weather variables were linked to changes in users’activities.Higher precipitation and lower temperature were associated with reducing the number of users and the diversity of registered activities.Most of the stationary activities were observed during summer.The diversity of the observed activities was associated with the available facilities rather than the park size.The distribution of stationary activities was spatially correlated with facility/equipment(benches,playgrounds,sports,and fitness equipment)and proximity to water features.The results of this study are relevant for UGS design,planning,and management. 展开更多
关键词 Urban parks Seasonal differences Temporal use Time of day Spatial distribution of UGS users
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Fast source mask co-optimization method for high-NA EUV lithography
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作者 Ziqi Li Lisong Dong +1 位作者 Xu Ma Yayi Wei 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第4期44-54,共11页
Extreme ultraviolet(EUV)lithography with high numerical aperture(NA)is a future technology to manufacture the integrated circuit in sub-nanometer dimension.Meanwhile,source mask co-optimization(SMO)is an extensively u... Extreme ultraviolet(EUV)lithography with high numerical aperture(NA)is a future technology to manufacture the integrated circuit in sub-nanometer dimension.Meanwhile,source mask co-optimization(SMO)is an extensively used approach for advanced lithography process beyond 28 nm technology node.This work proposes a novel SMO method to improve the image fidelity of high-NA EUV lithography system.A fast high-NA EUV lithography imaging model is established first,which includes the effects of mask three-dimensional structure and anamorphic magnification.Then,this paper develops an efficient SMO method that combines the gradient-based mask optimization algorithm and the compressivesensing-based source optimization algorithm.A mask rule check(MRC)process is further proposed to simplify the optimized mask pattern.Results illustrate that the proposed SMO method can significantly reduce the lithography patterning error,and maintain high computational efficiency. 展开更多
关键词 computational lithography high-NA EUV lithography source-mask co-optimization lithography imaging model
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Research on design and firing performance of Si-based detonator 被引量:6
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作者 Rui-zhen XIE Xiao-ming REN +3 位作者 Lan LIU Yan XUE Dong-xiao FU Rui ZHANG 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第1期34-39,共6页
For the chip integration of MEMS(micro-electromechanical system) safety and arming device, a miniature detonator needs to be developed to reduce the weight and volume of explosive train. A Si-based micro-detonator is ... For the chip integration of MEMS(micro-electromechanical system) safety and arming device, a miniature detonator needs to be developed to reduce the weight and volume of explosive train. A Si-based micro-detonator is designed and fabricated, which meets the requirement of MEMS safety and arming device. The firing sensitivity of micro-detonator is tested according to GJB/z377A-94 sensitivity test methods:Langlie. The function time of micro-detonator is measured using wire probe and photoelectric transducer. The result shows the average firing voltage is 6.4 V when the discharge capacitance of firing electro-circuit is 33 mF. And the average function time is 5.48 ms. The firing energy actually utilized by Si-based micro-detonator is explored. 展开更多
关键词 SI基 雷管 设计 解除保险装置 微机电系统 性能 烧制 测试方法
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Research of the Adaptive Beamformer Based on the Frequency Energy Normalization 被引量:1
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作者 马启明 王宣银 杜栓平 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期29-35,共7页
An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the ... An algorithm of broadband minimum variance distortionless response(MVDR) based on the frequency energy normalization is proposed.First,every narrowband frequency component of the broadband signal is normalized by the total narrowband energy of all array elements,and the narrowband power is calculated by MVDR.Finally,final spatial energy spectrum can be obtained by averaging or summing all results of every narrowband frequency bin.Any prior-information about the noise or the signal is unnecessary for the proposed method in this paper.The processing gain of the proposed method compared to the conventional broadband MVDR can be obtained as long as the amplitude fluctuation of the array noise frequency spectrum is severer than that of the target signal.The validity of the method is validated by the optimal signal detection theory.Simulation and real data are used to validate the performance of the method.Analysis results show that about 4 dB processing gain compared to the general broadband MVDR can be reached by the proposed method. 展开更多
关键词 自适应波束形成器 正常化 频率 能量 最小方差无畸变响应 宽带信号 MVDR 噪声频谱
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Thermal and ignition properties of hexanitrostilbene(HNS) microspheres prepared by droplet microfluidics 被引量:1
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作者 Rui-shan Han Fei-peng Lu +6 位作者 Fang Zhang Yan-lan Wang Mi Zhou Guo-sheng Qin Jian-hua Chen Hai-fu Wang En-yi Chu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期166-173,共8页
HNS-IV(Hexanitrostilbene-IV) is the main charge of the exploding foil initiators(EFI), and the microstructure of the HNS will directly affect its density, flowability, sensitivity, and stability. HNS microspheres were... HNS-IV(Hexanitrostilbene-IV) is the main charge of the exploding foil initiators(EFI), and the microstructure of the HNS will directly affect its density, flowability, sensitivity, and stability. HNS microspheres were prepared using droplet microfluidics, and the particle size, morphology, specific surface area, thermal performance, and ignition threshold of the HNS microspheres were characterized and tested. The results shown that the prepared HNS microspheres have high sphericity, with an average particle size of 20.52 μm(coefficient of variation less than 0.2), and a specific surface area of 21.62 m^(2)/g(6.87 m^(2)/g higher than the raw material). Without changing the crystal structure and thermal stability of HNS-IV, this method significantly enhances the sensitivity of HNS-IV to short pulses and reduces the ignition threshold of the slapper detonator to below 1000 V. This will contribute to the miniaturization and low cost of EFI. 展开更多
关键词 MICROFLUIDICS HNS microspheres Thermal stability Ignition threshold
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Groundwater quality in the vicinity of a dumpsite in Lagos metropolis,Nigeria
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作者 Carla S.S.Ferreira Onyanta Adama-Ajonye +1 位作者 Anosike EIkenna Zahra Kalantari 《Geography and Sustainability》 CSCD 2023年第4期379-390,共12页
Inappropriate management of municipal solid waste dumpsites is a major cause of groundwater contamination in developing countries,but the extent of the problem is not known.This study investigated groundwater quality ... Inappropriate management of municipal solid waste dumpsites is a major cause of groundwater contamination in developing countries,but the extent of the problem is not known.This study investigated groundwater quality in the vicinity of Olusosun dumpsite in Lagos,Nigeria,the most populous city in sub-Saharan Africa.During 2020,monthly groundwater samples were collected in 17 wells and boreholes used as drinking water sources,and analysed for 20 physico-chemical parameters.Differences between sites and seasons were statistically assessed,together with changes in water quality index(WQI).The results indicated that heavy metals(Pb^(2+),Ni^(+),Mn^(2+),Fe^(2+),Cr^(6+)),cations(Ca^(2+),Mg^(2+),K^(+)),total hardness and pH were the main parameters impairing water quality.Drinking water quality standards from both the World Health Organization and Nigeria government were exceeded more often in the wet season than in the dry season.Some groundwater properties were negatively correlated with distance to dumpsite(e.g.,Fe^(2+),Pb^(2+),NO_(3)^(−)).Significant differences between sites were identified,but with no clear spatial trend.WQI varied from excellent(6%-24%of the sites over the study period)to unsuitable for drinking water purposes(12%-18%),with good quality prevailing at most sites(35%-47%).Although groundwater quality declined at 24%of the sites over 2020,the results indicated improvements compared with previous decades.Remediation strategies must be implemented to safeguard public health and the sustainability of water resources. 展开更多
关键词 Municipal solid waste dumpsite Groundwater quality Seasonal variation Heavy metals NIGERIA
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Relationship Between Changes of River-lake Networks and Water Levels in Typical Regions of Taihu Lake Basin,China 被引量:6
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作者 YIN Yixing XU Youpeng CHEN Ying 《Chinese Geographical Science》 SCIE CSCD 2012年第6期673-682,共10页
The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river ne... The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river networks and lakes for different periods were investigated and the influences of river system evolution on water level changes were further explored through the comparison of their fractal characters.The results are as follows:1) River network development of the study area is becoming more monotonous and more simple;the number of lakes is reducing significantly,and the water surface ratio has dropped significantly since the 1980s.2) The box dimension of the river networks in all the cities of the study area decreased slowly from the 1960s to the 1980s,while the decrease was significant from the 1980s to the 2000s.The variations of lake correlation dimension are similar to those of the river network box dimensions.This is unfavorable for the storage capacity of the river networks and lakes.3) The Hurst exponents of water levels were all between 0.5 and 1.0 from the 1960s to the 1980s,while decreased in the 2000s,indicating the decline in persistence and increase in the complexity of water level series.The paper draws a conclusion that the relationship between the fractal dimension of river-lake networks and the Hurst exponents of the water level series can reveal the impacts of river system changes on flood disasters to some extent:the disappearance of river networks and lakes will increase the possibility of flood occurrence. 展开更多
关键词 水位变化 太湖流域 网络 典型地区 江湖 中国 HURST指数 分形维数
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Application of Mellin Transform in Wideband Underwater Acoustic Signal Processing 被引量:2
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作者 王军 李亚安 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第4期297-301,共5页
According to the features of the wideband underwater acoustic signals,an algorithm for the wideband ambiguity function is put forward based on Mellin transform.The wideband acoustic signal processing using the fast Me... According to the features of the wideband underwater acoustic signals,an algorithm for the wideband ambiguity function is put forward based on Mellin transform.The wideband acoustic signal processing using the fast Mellin transform is also explored.The theoretical analysis and simulation results show that the algorithm has not only high computation efficiency but also good concentration in wideband ambiguity domain.It suits for the wideband underwater acoustic signal processing. 展开更多
关键词 声学 多频率信号 多频率模糊函数 Mellin转换 信号处理 地下水声
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How does the Indian Ocean subtropical dipole trigger the tropical Indian Ocean dipole via the Mascarene high? 被引量:3
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作者 FENG Junqiao HU Dunxin YU Lejiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期64-76,共13页
The variation in the Indian Ocean is investigated using Hadley center sea surface temperature(SST) data during the period 1958–2010.All the first empirical orthogonal function(EOF) modes of the SST anomalies(SST... The variation in the Indian Ocean is investigated using Hadley center sea surface temperature(SST) data during the period 1958–2010.All the first empirical orthogonal function(EOF) modes of the SST anomalies(SSTA) in different domains represent the basin-wide warming and are closely related to the Pacific El Ni o– Southern Oscillation(ENSO) phenomenon.Further examination suggests that the impact of ENSO on the tropical Indian Ocean is stronger than that on the southern Indian Ocean.The second EOF modes in different domains show different features.It shows a clear east-west SSTA dipole pattern in the tropical Indian Ocean(Indian Ocean dipole,IOD),and a southwest-northeast SSTA dipole in the southern Indian Ocean(Indian Ocean subtropical dipole,IOSD).It is further revealed that the IOSD is also the main structure of the second EOF mode on the whole basin-scale,in which the IOD pattern does not appear.A correlation analysis indicates that an IOSD event observed during the austral summer is highly correlated to the IOD event peaking about 9 months later.One of the possible physical mechanisms underlying this highly significant statistical relationship is proposed.The IOSD and the IOD can occur in sequence with the help of the Mascarene high.The SSTA in the southwestern Indian Ocean persists for several seasons after the mature phase of the IOSD event,likely due to the positive wind–evaporation–SST feedback mechanism.The Mascarene high will be weakened or intensified by this SSTA,which can affect the atmosphere in the tropical region by teleconnection.The pressure gradient between the Mascarene high and the monsoon trough in the tropical Indian Ocean increases(decreases).Hence,an anticyclone(cyclone) circulation appears over the Arabian Sea-India continent.The easterly or westerly anomalies appear in the equatorial Indian Ocean,inducing the onset stage of the IOD.This study shows that the SSTA associated with the IOSD can lead to the onset of IOD with the aid of atmosphere circulation and also explains why some IOD events in the tropical tend to be followed by IOSD in the southern Indian Ocean. 展开更多
关键词 Indian Ocean dipole Indian Ocean subtropical dipole Mascarene high
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Blue-Green Electroluminescence of Free-Standing Diamond Thin Films 被引量:3
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作者 ZHANG Binglin SHEN Shupo +4 位作者 WANG Jian’en HE Jintian Howard R.Shanks Moeljanto W.Leksono Robert Girvan 《Chinese Physics Letters》 SCIE CAS CSCD 1994年第4期235-238,共4页
Blue-green electroluminescence has been observed in free-standing diamond films which were deposited by microwave plasma assisted CVD on silicon substrates.The electroluminescence device is driven by a 60 Hz power sup... Blue-green electroluminescence has been observed in free-standing diamond films which were deposited by microwave plasma assisted CVD on silicon substrates.The electroluminescence device is driven by a 60 Hz power supply.The threshold voltage was about 112 V peak-to-peak.The electroluminescence spectrum at room temperature,showed a blue-green band with the peak centered at 485nm suggesting band A type emission.Electroluminescence was also observed at 77K. 展开更多
关键词 ELECTROLUMINESCENCE DIAMOND FILMS
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Synthesis and Crystal Structure of(E)-Ethyl 2-(5-(3-methyl-2-butenyloxy)-2-(3-(4-(3-methyl-2-butenyloxy)phenyl)acryloyl)phenoxy)acetate 被引量:1
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作者 王建国 伍林 +3 位作者 钟婵娟 齐小燕 周锦霞 易德莲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期604-608,共5页
The title compound,(E)-ethyl 2-(5-(3-methyl-2-butenyloxy)-2-(3-(4-(3-methyl-2-butenyloxy)phenyl) acryloyl) phenoxy)acetate(1),has been synthesized and characterized by FT-IR and 1H-NMR spectroscopy,ESI-M... The title compound,(E)-ethyl 2-(5-(3-methyl-2-butenyloxy)-2-(3-(4-(3-methyl-2-butenyloxy)phenyl) acryloyl) phenoxy)acetate(1),has been synthesized and characterized by FT-IR and 1H-NMR spectroscopy,ESI-MS,and X-ray single-crystal diffraction.FT-IR,1H-NMR and ESI-MS confirm the functional groups,particularly the ethyl groups in the ester moiety,of the compound.The single-crystal X-ray diffraction has revealed a monoclinic structure,space group P21/n with a = 14.6832(14),b = 7.7581(7),c = 23.075(2),β = 101.670(2)o,V = 2574.2(4) ?3,Z = 4,Dc = 1.235 g/cm,μ = 0.085 mm-1,and F(000) = 1024.The skeleton of chalcone in the molecular structure is coplanar. 展开更多
关键词 sofalcone intermediate synthesis crystal structure
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Role of Western Pacific Oceanic Variability in the Onset of the Bay of Bengal Summer Monsoon 被引量:1
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作者 冯俊乔 胡敦欣 于乐江 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第1期219-234,共16页
The influence of the tropical Indo-Pacific Ocean heat content on the onset of the Bay of Bengal summer monsoon (BOBSM) onset was investigated using atmospheric data from the NCEP and ocean subsurface temperature dat... The influence of the tropical Indo-Pacific Ocean heat content on the onset of the Bay of Bengal summer monsoon (BOBSM) onset was investigated using atmospheric data from the NCEP and ocean subsurface temperature data from the Japan Metorology Agency (JMA). Results showed that the onset time of the BOBSM is highly related to the tropical Pacific upper ocean heat content (HC), especially in the key region of the western Pacific warm pool (WPWP), during the preceding winter and spring. When the HC anomalies in the WPWP are positive (negative), the onset of the BOBSM is usually early (late). Accompanied by the variation of the convection activity over the WPWP, mainly induced by the underlying ocean temperature anomalies, the Walker circulation becomes stronger or weaker. This enhances or weakens the westerly over the tropical Indian Ocean flowing into the BOB in the boreal spring, which is essential to BOBSM onset. The possible mechanism of influence of cyclonic/anti-cyclonic circulation over the northwestern tropical Pacific on BOBSM onset is also discussed. 展开更多
关键词 summer monsoon onset ocean heat content warm pool Bay of Bengal
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Low-Frequency Coupled Atmosphere-Ocean Variability in the Southern Indian Ocean 被引量:1
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作者 冯俊乔 胡敦欣 于乐江 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第3期544-560,共17页
The low-frequency atmosphere ocean coupled vestigated using observation data over 1958-2010 variability of the southern Indian Ocean (SIO) was in- These data were obtained from ECMWF for sea level pressure (SLP) ... The low-frequency atmosphere ocean coupled vestigated using observation data over 1958-2010 variability of the southern Indian Ocean (SIO) was in- These data were obtained from ECMWF for sea level pressure (SLP) and wind, from NCEP/NCAR for heat fluxes, and from the Hadley Center for SST. To obtain the coupled air-sea variability, we performed SVD analyses on SST and SLP. The primary coupled mode represents 43% of the total square covariance and is featured by weak westerly winds along 45~ 30~S. This weakened subtropical anticyclone forces fluctuations in a well-known subtropical dipole structure in the SST via wind-induced processes. The SST changes in response to atmosphere forcing and is predictable with a lead-time of 1 2 months. Atmosphere ocean coupling of this mode is strongest during the austral summer. Its principle component is characterized by mixed interannual and interdeeadal fluctuations. Titere is a strong relationship between the first mode and Antarctic Oscillation (AAO). The AAO can influence tile coupled processes in the SIO by modulating the subtropical high. The second mode, accounting for 30% of the total square covariance, represents a 25-year period interdecadal oscillation in tile strength of the subtropical anticyclone that is accompanied by fluctuations of a monopole structure in the SST along the 35~ 25~S band. It is caused by subsidence of the atmosphere. The present study also shows that physical processes of both local thermodynamic and ocean circulation in the SIO have a crucial role in the fornmtion of the atmosphere-ocean eovariability. 展开更多
关键词 southern Indian Ocean SST SLP Antarctic Oscillation
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A public Cloud-based China's Landslide Inventory Database(Cs LID): development, zone, and spatiotemporal analysis for significant historical events, 1949-2011 被引量:4
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作者 LI Wei-yue LIU Chun +9 位作者 HONG Yang ZHANG Xin-hua WAN Zhan-ming Manabendra SAHARIA SUN Wei-wei YAO Dong-jing CHEN Wen CHEN Sheng YANG Xiu-qin YUE Jing 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1275-1285,共11页
Landslide inventory plays an important role in recording landslide events and showing their temporal-spatial distribution. This paper describes the development, visualization, and analysis of a China's Landslide I... Landslide inventory plays an important role in recording landslide events and showing their temporal-spatial distribution. This paper describes the development, visualization, and analysis of a China's Landslide Inventory Database(Cs LID) by utilizing Google's public cloud computing platform. Firstly, Cs LID(Landslide Inventory Database) compiles a total of 1221 historical landslide events spanning the years 1949-2011 from relevant data sources. Secondly, the Cs LID is further broken down into six zones for characterizing landslide cause-effect, spatiotemporal distribution, fatalities, and socioeconomic impacts based on the geological environment and terrain. The results show that among all the six zones, zone V, located in Qinba and Southwest Mountainous Area is the most active landslide hotspot with the highest landslide hazard in China. Additionally, the Google public cloud computing platform enables the Cs LID to be easily accessible, visually interactive, and with the capability of allowing new data input to dynamically augment the database. This work developed a cyber-landslide inventory and used it to analyze the landslide temporal-spatial distribution in China. 展开更多
关键词 滑坡灾害 历史事件 数据库 开发区 中国 时空分析 CS 政务公开
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DNA methylation-mediated expression of zinc finger protein 615 affects embryonic development in Bombyx mori 被引量:1
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作者 Guan-Feng Xu Cheng-Cheng Gong +8 位作者 Yu-Lin Tian Tong-Yu Fu Yi-Guang Lin Hao Lyu Yu-Ling Peng Chun-Mei Tong Qi-Li Feng Qi-Sheng Song Si-Chun Zheng 《Zoological Research》 SCIE CAS CSCD 2022年第4期552-565,共14页
Cell division and differentiation after egg fertilization are critical steps in the development of embryos from single cells to multicellular individuals and are regulated by DNA methylation via its effects on gene ex... Cell division and differentiation after egg fertilization are critical steps in the development of embryos from single cells to multicellular individuals and are regulated by DNA methylation via its effects on gene expression.However,the mechanisms by which DNA methylation regulates these processes in insects remain unclear.Here,we studied the impacts of DNA methylation on early embryonic development in Bombyx mori.Genome methylation and transcriptome analysis of early embryos showed that DNA methylation events mainly occurred in the 5'region of protein metabolism-related genes.The transcription factor gene zinc finger protein 615(ZnF615)was methylated by DNA methyltransferase 1(Dnmt1)to be up-regulated and bind to protein metabolism-related genes.Dnmt1 RNA interference(RNAi)revealed that DNA methylation mainly regulated the expression of nonmethylated nutrient metabolism-related genes through ZnF615.The same sites in the ZnF615 gene were methylated in ovaries and embryos.Knockout of ZnF615 using CRISPR/Cas9 gene editing decreased the hatching rate and egg number to levels similar to that of Dnmt1 knockout.Analysis of the ZnF615 methylation rate revealed that the DNA methylation pattern in the parent ovary was maintained and doubled in the offspring embryo.Thus,Dnmt1-mediated intragenic DNA methylation of the transcription factor ZnF615 enhances its expression to ensure ovarian and embryonic development. 展开更多
关键词 DNA methylation Embryonic development Transcriptional regulation EPIGENETIC
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Study on the Temperature of the Bridge Wire in the Initiator Used in Nuclear Explosion Valve 被引量:1
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作者 Lan Shi An-Min Yang +2 位作者 Ying-Chun Zhang Yuan-He Wang Zhanying Li 《American Journal of Analytical Chemistry》 2016年第12期908-917,共10页
This paper established the mathematical model of bridge wire temperature rise under direct current condition and gave the solution. It computed bridge wire temperature by using the thermal-electric coupling method pro... This paper established the mathematical model of bridge wire temperature rise under direct current condition and gave the solution. It computed bridge wire temperature by using the thermal-electric coupling method provided by ANSYS-Workbench finite element analysis software. In the end, the temperature bridge wire applied to different electric current was measured by the infrared thermal imaging temperature measurement method. The result shows that the ANSYS simulation results are in agreement with the theoretical calculation and the experimental results. It is feasible to compute bridge wire temperature of initiator by using ANSYS-Workbench software, and it is an important method to analyze complex structure of pyrotechnics. 展开更多
关键词 Bridge Wire Temperature ANSYS-Workbench Thermal-Electric Coupling Infrared Thermal Imaging
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Ultrasonic Pulse Signal Resonance Features in Layered CFRP Within Voids 被引量:1
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作者 杨辰龙 陈越超 +1 位作者 WANG Zhe ZHENG Huifeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第3期695-702,共8页
The ultrasonic pulse signal resonance features in layered carbon fiber reinforced plastic(CFRP) within voids were researched. The frequency domain model of acoustic wave propagation in multilayered medium was establ... The ultrasonic pulse signal resonance features in layered carbon fiber reinforced plastic(CFRP) within voids were researched. The frequency domain model of acoustic wave propagation in multilayered medium was established. Then the reflection coefficient of multilayered CFRP within voids was numerically calculated. The results are as follows. When the CFRP laminate is tested by ultrasonic whose center frequency is close to the CFRP inherent resonant frequency, the ultrasonic may generate resonance phenomenon in CFRP. If CFRP contains evenly distributed voids, the frequency of resonant signal and its amplitude all decrease with the increase of porosity. For the thick section CFRP within local concentrated voids, the local concentrated voids near testing surface will cause signal frequency reduction and the decrease of its amplitude. But the voids which exist in layers far away from testing surface almost have no influence on signal resonance. The ultrasonic pulse echo testing was conducted for thick section CFRP specimen. The analysis results of testing signals were in accordance with the results of the numerical calculation, showing that the reflection coefficient frequency response model can effectively explain the ultrasonic resonance phenomenon in layered CFRP within voids. 展开更多
关键词 carbon fiber reinforced plastic void resonance reflection coefficient frequency response
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Study on applicability of modal analysis of thin finite length cylindrical shells using wave propagation approach
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作者 李冰茹 王宣银 +1 位作者 葛辉良 丁渊明 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1122-1127,共6页
Donnell’s thin shell theory and basic equations based on the wave propagation method discussed in detail here, is used to investigate the natural frequencies of thin finite length circular cylindrical shells under va... Donnell’s thin shell theory and basic equations based on the wave propagation method discussed in detail here, is used to investigate the natural frequencies of thin finite length circular cylindrical shells under various boundary conditions. Mode shapes are drawn to explain the circumferential mode number n and axial mode number m, and the natural frequencies are cal-culated numerically and compared with those of FEM (finite element method) to confirm the reliability of the analytical solution. The effects of relevant parameters on natural frequencies are discussed thoroughly. It is shown that for long thin shells the method is simple, accurate and effective. 展开更多
关键词 波传递 圆柱形 自然频率 有限长度 边界条件
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Berry Phase of Spinor Fields Induced by Gravity and Inertia
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作者 WU Youlin MENG Guangda 《Chinese Physics Letters》 SCIE CAS CSCD 1995年第4期193-196,共4页
The Berry phase of spinor fields induced by gravity and inertia are studied starting with covariant Dirac equation in general relativity.The results obtained reveal the spin-gravity coupling effect explicitly.As examp... The Berry phase of spinor fields induced by gravity and inertia are studied starting with covariant Dirac equation in general relativity.The results obtained reveal the spin-gravity coupling effect explicitly.As examples the phase shifts induced by inertial fields of rotating frame and by Earth’s fields are evaluated and some comments on the evaluation are discussed. 展开更多
关键词 BERRY STARTING ROTATING
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