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In-doping collaboratively controlling back interface and bulk defects to achieve efficient flexible CZTSSe solar cells
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作者 Quanzhen Sun Yifan Li +6 位作者 Caixia Zhang Shunli Du Weihao Xie Jionghua Wu Qiao Zheng Hui Deng Shuying Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期10-17,I0002,共9页
Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface... Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface and passivate deep level defects in CZTSSe bulk concurrently for improving the performance of flexible device.The results show that In doping effectively inhibits the formation of secondary phase(Cu(S,Se)_(2))and VSndefects.Further studies demonstrate that the barrier height at the back interface is decreased and the deep level defects(Cu_(Sn)defects)in CZTSSe bulk are passivated.Moreover,the carrier concentration is increased and the V_(OC) deficit(V_(OC,def))is decreased significantly due to In doping.Finally,the flexible CZTSSe solar cell with 10.01%power conversion efficiency(PCE)has been obtained.The synergistic strategy of interface modification and bulk defects passivation through In incorporation provides a new thought for the fabrication of efficient flexible kesterite-based solar cells. 展开更多
关键词 Flexible solar cells Cu_(2)Znsn(s se)_(4) Back interface Deep level defects Barrier height
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Stafne’s Bone Defect in Atypical Location: Between the Subcondylar Region and Neck of the Mandible Ramus 被引量:4
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作者 Francisco Barbosa de Araújo Neto Stefanie Gallotti Borges Carneiro +6 位作者 Dalton Yukio Araújo Fugita Flávio Henrique Martins Lessa José Dilermando Gotardo Vinícius Martins Valois Raphael Gomes Teixeira Tiago Bezerra Albano Erick Falci Santos 《Open Journal of Medical Imaging》 2017年第3期124-129,共6页
CONTEXT: Stafne’s bone defect is a benign lesion appearing on the image as a round radiolucent lesion within a cortical defect on the mandible. CASE REPORT: We attend one 46-year-old male patient came for diagnostic ... CONTEXT: Stafne’s bone defect is a benign lesion appearing on the image as a round radiolucent lesion within a cortical defect on the mandible. CASE REPORT: We attend one 46-year-old male patient came for diagnostic evaluation of a rounded and radiolucent lesion in the transition of the subcondylar region and neck of the left mandible ramus incidentally found by a dentist. Computed tomography and magnetic resonance imaging were performed in medical radiology and a Stafne’s cyst was diagnosed in an atypical location. CONCLUSION: We emphasize that Stafne’s bone defect is a benign lesion, whose imaging diagnosis can be conclusive, avoiding unnecessary surgical procedures. 展开更多
关键词 TOMOGRAPHY stafne’s BONY defect MANDIBLE
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A Fast Defects Location Method in ICT Images Based on Block Fractal Dimension
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作者 CHEN Pei-xing WANG Ming-quan +1 位作者 HOU Hui-ling LI Shi-hu 《Computer Aided Drafting,Design and Manufacturing》 2015年第1期1-6,共6页
Non-destructive testing (NDT) has been widely used in many fields, we can easily see it is being used in shipbuilding, aerospace, weapons manufacturing and so on. ICT is one of the best non destructive testing metho... Non-destructive testing (NDT) has been widely used in many fields, we can easily see it is being used in shipbuilding, aerospace, weapons manufacturing and so on. ICT is one of the best non destructive testing methods currently, but it has not been used widely, because it requires much compute and costs much time. Defect location is one of the most important processing steps in the digital image analysis. Defect location would correspondingly reduce the time spent in the testing. We may only require locating the defects in some case. So, we divide the CT images into several little blocks which the square is equal, and then calculate the fractal on each block. By determining the value and connected region number of the fractal dimension, we can locate defects of the image. The results show that the block ffactal dimension is a useful and time-saving defect location method. 展开更多
关键词 defect location fractal dimension BLOCK ICT EDGE
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基于S变换模能量分析的直流电缆故障测距
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作者 夏向阳 刘奕玹 +3 位作者 刘雄 夏君山 王瑞琪 朱鹏 《高压电器》 CAS CSCD 北大核心 2024年第7期201-209,共9页
针对现有高压直流电缆故障定位方法故障定位精度低、定位模型泛化能力差等问题,文中在考虑电缆故障后故障点产生的暂态信号中含有丰富的故障信息的特征,提出一种时频域能量分析的故障测距方法。该方法利用多分类支持向量机(SVM)的特性... 针对现有高压直流电缆故障定位方法故障定位精度低、定位模型泛化能力差等问题,文中在考虑电缆故障后故障点产生的暂态信号中含有丰富的故障信息的特征,提出一种时频域能量分析的故障测距方法。该方法利用多分类支持向量机(SVM)的特性构建直流电缆故障定位模型,利用直流电缆相模解耦矩阵对电缆电气量解耦,并采用S变换进行时频域变换,将得到的模量构造模能量,将其作为样本对SVM模型训练。实验结果表明,所提方法对于不同故障类型在不同过渡电阻及不同位置故障下均可进行准确测距。 展开更多
关键词 s变换 sVM模型 相模解耦 模能量 故障定位
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Tunable vacancy defect chemistry on free-standing carbon cathode for lithium-sulfur batteries 被引量:2
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作者 Xi Zhang Xiaohong Liu +1 位作者 Wei Zhang Yingze Song 《Green Energy & Environment》 SCIE EI CSCD 2023年第2期354-359,共6页
The defect chemistry is successfully modulated on free-standing and binder-free carbon cathodes for highly efficient Li-S redox reactions.Such rationally regulated defect engineering realizes the synchronization of io... The defect chemistry is successfully modulated on free-standing and binder-free carbon cathodes for highly efficient Li-S redox reactions.Such rationally regulated defect engineering realizes the synchronization of ion/electron-conductive and defect-rich networks on the threedimension carbon cathode,leading to its tunable activity for both relieving the shuttle phenomenon and accelerating the sulfur redox reaction kinetics.As expected,the defective carbon cathode harvests a high rate capacity of 1217.8 mAh g^(-1)at 0.2 C and a superior capacity retention of61.7%at 2 C after 500 cycles.Even under the sulfur mass loading of 11.1 mg cm^(-2),the defective cathode still holds a remarkable areal capacity of 8.5 mAh cm^(-2). 展开更多
关键词 Li–s chemistry Tunable vacancy defects Free-standing cathode Electrocatalytic activity sulfur redox reaction kinetics
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Comparison of ground truth location of earthquake from InSAR and from ambient seismic noise: A case study of the 1998 Zhangbei earthquake 被引量:8
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作者 Jun Xie Xiangfang Zeng +1 位作者 Weiwen Chen Zhongwen Zhan 《Earthquake Science》 CSCD 2011年第2期239-247,共9页
Because ambient seismic noise provides estimated Green’s function (EGF) between two sites with high accuracy, Rayleigh wave propagation along the path connecting the two sites is well resolved. Therefore, earthquak... Because ambient seismic noise provides estimated Green’s function (EGF) between two sites with high accuracy, Rayleigh wave propagation along the path connecting the two sites is well resolved. Therefore, earthquakes which are close to one seismic station can be well located with calibration extracting from EGF. We test two algorithms in locating the 1998 Zhangbei earthquake, one algorithm is waveform-based, and the other is traveltime-based. We first compute EGF between station ZHB (a station about 40 km away from the epicenter) and five IC/IRIS stations. With the waveform-based approach, we calculate 1D synthetic single-force Green’s functions between ZHB and other four stations, and obtain traveltime corrections by correlating synthetic Green’s functions with EGFs in period band of 10–30 s. Then we locate the earthquake by minimizing the differential travel times between observed earthquake waveform and the 1D synthetic earthquake waveforms computed with focal mechanism provided by Global CMT after traveltime correction from EGFs. This waveform-based approach yields a location which error is about 13 km away from the location observed with InSAR. With the traveltime-based approach, we begin with measuring group velocity from EGFs as well as group arrival time on observed earthquake waveforms, and then locate the earthquake by minimizing the difference between observed group arrival time and arrival time measured on EGFs. This traveltime-based approach yields accuracy of 3 km, Therefore it is feasible to achieve GT5 (ground truth location with accuracy 5 km) with ambient seismic noises. The less accuracy of the waveform-based approach was mainly caused by uncertainty of focal mechanism. 展开更多
关键词 ambient seismic noise estimated Green’s function ground truth location Rayleigh wave
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Dynamic Pathology and Antigen Location Study on Broiler Breeders with Coinfection of Marek's Disease Virus and Reticuloendotheliosis Virus 被引量:1
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作者 DIAO Xiu-guo ZHU Guo CHENG Zi-qiang WANG Gui-hua MENG Xiang-kai GAO Ting-ting CUI Zhi-zhong 《Agricultural Sciences in China》 CAS CSCD 2008年第11期1387-1393,共7页
To further understand the generation and development of coinfection of Marek's disease virus (MDV) and reticuloendotheliosis virus (REV) in broiler breeders, and then find the method and optimal time of different... To further understand the generation and development of coinfection of Marek's disease virus (MDV) and reticuloendotheliosis virus (REV) in broiler breeders, and then find the method and optimal time of differential diagnosis for complex clinic multiple infection, the authors studied the pathohistological changes, apoptosis, immunohistochemistry (immunofluorescence), and ultrastructure of tumor tissues of broiler breeders inoculated with MDV and REV. The study showed that proliferation of small lymphocytes was seen in the main organs at the age of 1 week, then immature lymphocytes, all kinds of lymphocytes, primitive reticulum cells, and Marek's disease cells (MDCs) were observed at 2-9 weeks. Apoptosis of lymphocytes could not be seen until the age of 10 weeks in the immune system. Immunohistochemistry detection showed that the positive signs of MDV and REV antigen were observed in the main organs at 2 weeks of age. Multi-morphology lymphocytes, MDV, and REV, mitotic figures and apoptosis of lymphocytes were observed with the help of transmission electron microscopy. MDV cooperating with REV promotes the course of disease of coinfection. Differential diagnosis can be done by immunohistochemistry in the early stage (before 2 weeks), and histopathology in the late stage (post 4 weeks). MDCs, primitive reticulum cells, immature lymphocytes, and two kinds of virions can serve as a basis for bistopathology differential diagnosis. 展开更多
关键词 Marek's disease virus reticuloendotheliosis virus COINFECTION dynamic pathology antigen location
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2023年甘肃积石山M_(S)6.2地震精定位及发震构造研究
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作者 陈科睿 陈继锋 尹欣欣 《地震工程学报》 CSCD 北大核心 2024年第4期932-941,共10页
采用双差定位的方法,对2023年12月18日甘肃省积石山县M_(S)6.2地震的余震(震后一周)进行重定位,最后获得438个地震事件(包含主震)的位置。定位结果显示余震主要呈NNW向分布,长度约为16 km;主震位于余震带的中央偏东北处,余震分布与拉脊... 采用双差定位的方法,对2023年12月18日甘肃省积石山县M_(S)6.2地震的余震(震后一周)进行重定位,最后获得438个地震事件(包含主震)的位置。定位结果显示余震主要呈NNW向分布,长度约为16 km;主震位于余震带的中央偏东北处,余震分布与拉脊山断裂近似平行,与主震的震源机制解吻合;余震的震源深度主要集中在6.5~12 km,主震深度为11.5 km。从沿断裂走向的剖面可以观察到,此次地震的浅地表余震事件较少,因此未造成明显的地表破裂。对发震断裂的分析表明,拉脊山断裂带的走滑速率较低,这可能代表其处于强锁定阶段。此外,地震聚类分析表明,尽管北拉脊山断裂是主要发震断裂,南拉脊山断裂与此次地震的发震构造也存在紧密联系。 展开更多
关键词 积石山M_(s)6.2地震 双差定位 震源机制 发震构造 时空演化
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基于改进YOLOX-s算法的航天太阳电池缺陷检测
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作者 李振伟 张仕海 +2 位作者 屈重年 汝承印 陈康静 《太阳能学报》 EI CAS CSCD 北大核心 2024年第9期276-284,共9页
针对航天太阳电池表面缺陷检测问题,提出基于机器视觉与深度学习的缺陷检测方法。通过航天太阳电池缺陷检测系统获取图像,并依据企业电池片缺陷的分类标准构建航天太阳电池缺陷数据集。采用切片技术获取包含缺陷目标的子图像数据集,解... 针对航天太阳电池表面缺陷检测问题,提出基于机器视觉与深度学习的缺陷检测方法。通过航天太阳电池缺陷检测系统获取图像,并依据企业电池片缺陷的分类标准构建航天太阳电池缺陷数据集。采用切片技术获取包含缺陷目标的子图像数据集,解决卷积和下采样操作信息丢失而导致召回率低的问题。针对不同缺陷采取适当的图像增强方式进行扩充数据集,以避免训练过程中因数据集不足导致的过拟合问题。采用深度可分离卷积、优化损失函数、双线性插值上采样及引入注意力机制等方法对YOLOX-s算法进行改进,以获得综合效果最佳的航天太阳电池缺陷检测模型。通过不同数据集训练及检测精度指标对比,以及消融实验验证改进模型的有效性。通过改进模型与同类主流模型对比实验,验证改进模型在航天太阳电池缺陷检测方面的优越性。 展开更多
关键词 太阳电池 机器视觉 深度学习 YOLOX-s 缺陷检测
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改进YOLOX-S的偏光片表面缺陷检测算法 被引量:1
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作者 陈乐 周永霞 祖佳贞 《计算机工程与应用》 CSCD 北大核心 2024年第2期295-303,共9页
偏光片是液晶显示器的重要组成部分,其表面缺陷不仅会降低液晶显示器的显示质量,甚至可能造成整个液晶面板的报废。针对偏光片表面缺陷存在尺度差异大、形状变化多样的问题,提出一种改进YOLOX-S的偏光片表面缺陷检测算法。提出自适应平... 偏光片是液晶显示器的重要组成部分,其表面缺陷不仅会降低液晶显示器的显示质量,甚至可能造成整个液晶面板的报废。针对偏光片表面缺陷存在尺度差异大、形状变化多样的问题,提出一种改进YOLOX-S的偏光片表面缺陷检测算法。提出自适应平衡特征金字塔(ABFP)模块充分融合主干网提取的多级特征,并通过单个卷积增加检测分支,进一步增强模型的多尺度检测能力。在ABFP中引入注意力模块CBAM关注重要特征。采用CIo U损失函数的同时使用Mish激活函数替代Si LU激活函数。实验结果表明,改进的算法在偏光片表面缺陷数据集上的m AP_(50)和m AP_(50:95)分别达到92.97%和55.16%,相比YOLOX-S(FPN)提升了1.86和1.34个百分点,每秒检测帧数(FPS)达到50,基本满足工业实时检测的需求。 展开更多
关键词 偏光片表面 缺陷检测 YOLOX-s 自适应平衡特征金字塔 CIoU Mish
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Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors
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作者 DING Ning WANG Siyu +4 位作者 YU Shihua XU Pengcheng HAN Dandan SHI Dexin ZHANG Chao 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1784-1794,共11页
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz... Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities. 展开更多
关键词 crystalline@amorphous heterostructure NiCo2s4@Mos2 hybrid supercapacitor defect design long cycle life
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地震预警台站在地震定位中的应用——以四川泸定M_(S)6.8地震为例
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作者 侯泽宇 马康熙 +2 位作者 朱永莉 王宇航 李萍萍 《四川地震》 2024年第1期19-23,共5页
为了研究预警台站在地震定位中的应用效果,本文以2022年9月5日四川泸定M_(S)6.8地震为例,基于地震预警台站观测资料,使用LOC3D定位方法对主震及2022年9月9日前MS≥3.0余震进行重定位。结果表明:泸定M_(S)6.8地震震中位置与人工目录结果... 为了研究预警台站在地震定位中的应用效果,本文以2022年9月5日四川泸定M_(S)6.8地震为例,基于地震预警台站观测资料,使用LOC3D定位方法对主震及2022年9月9日前MS≥3.0余震进行重定位。结果表明:泸定M_(S)6.8地震震中位置与人工目录结果基本一致;预警台站观测资料的加入能够增加各个方位的台站覆盖率,增加近台数量,提供地震事件S波完整震相,有效地约束地震定位结果中的震源深度,提升了地震定位精度,为地震定位提供更全面有效的数据支撑。 展开更多
关键词 地震定位 地震预警台站 泸定M_(s)6.8地震
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Possible Effects of Location and Handling on Some Fungi Associated with Rotting <i>Citrullus lanatus</i>Thunb. (Watermelon)
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作者 Ayodele Adegboyega Sobowale 《American Journal of Plant Sciences》 2019年第6期1061-1068,共8页
An experiment was conducted to examine probable impact of location and handling on the fungi commonly associated with rotting watermelon (Citrullus lanatus). The rotting watermelon samples were obtained from two vendo... An experiment was conducted to examine probable impact of location and handling on the fungi commonly associated with rotting watermelon (Citrullus lanatus). The rotting watermelon samples were obtained from two vendors each from five different markets (Bodija, Sango, Mokola, Eleyele, Agbowo and Ojoo) in Ibadan, Oyo state. They were placed in different sterile sample bags which were labeled appropriately before bringing them to the Pathology Laboratory, Department of Botany, University of Ibadan. Isolation of fungi from the rotting samples was carried out using pour plate method on acidified Potato Dextrose Agar (APDA). Pathogenicity test was also conducted for the isolated fungi. All experiments were done in duplicates and all plates were incubated at 25&deg;C ± 2&deg;C for 7 days. Pure cultures were obtained and identified and each isolated fungus was recorded as 1 which means present and 0 which means absent. The data obtained were analyzed using SAS version 9.3 at p ≤ 0.05. A total of three fungi were isolated viz., Aspergillus flavus, Saccharomyces cerevisae and Aspergillus niger. Occurrence of A. niger and A. flavus in samples obtained from Bodija, Mokola, Sango and Ojoo markets were significantly (P ≤ 0.05) higher than those from the other two markets. Occurrence of S. cerevisae in samples obtained from Bodija and Mokola markets were significantly (P ≤ 0.05) higher than those from the other three markets. Location had significant impact on the occurrence of isolated fungi in the rotting watermelons. However, handling by vendors had no significant impact on occurrence of the isolated fungi. Vendors and consumers are advised to be mindful of place of purchase and to also maintain good general hygiene before consumption. 展开更多
关键词 WATERMELON A. FLAVUs s. cerevisae A. NIGER locations Vendors
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网格搜索定位方法的准确度及其影响因素分析——以2019年四川长宁M_(S)6.0地震为例
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作者 张风雪 胡莉娅 李昱 《四川地震》 2024年第2期24-28,共5页
地震位置的准确度是开展高精度壳幔结构研究的重要基础。由于地震台站间距的稀疏性,地震台网发布的地震位置存在较大的水平误差,其深度的不确定性更是其水平不确定性的数倍之多,地震位置准确度还未达到开展高精度结构研究的要求。因此,... 地震位置的准确度是开展高精度壳幔结构研究的重要基础。由于地震台站间距的稀疏性,地震台网发布的地震位置存在较大的水平误差,其深度的不确定性更是其水平不确定性的数倍之多,地震位置准确度还未达到开展高精度结构研究的要求。因此,研究学者需要综合分析多种影响因素且对地震位置进行合理优化后,才可利用它获得较为可靠的壳幔结构。本研究以2019年长宁M_(S)6.0地震为例,使用基于正演的网格搜索定位方法,定性验证了不完备的方位角和难以准确识别的S震相走时会对震源位置的准确性产生较大影响,定量分析了观测数据量和速度模型与震源深度间的制约关系,这些影响因素基本遵循前人已获得的认知准则。另外,该次研究还发现BJT和ZYT地震台站可能存在较大的授时偏差。 展开更多
关键词 地震定位 长宁Ms6.0地震 定位准则
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Location and moment tensor inversion of small earthquakes using 3D Green's functions in models with rugged topography: application to the Longmenshan fault zone
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作者 Li Zhou Wei Zhang +2 位作者 Yang Shen Xiaofei Chen Jie Zhang 《Earthquake Science》 CSCD 2016年第3期139-151,共13页
With dense seismic arrays and advanced imaging methods, regional three-dimensional (3D) Earth models have become more accurate. It is now increasingly feasible and advantageous to use a 3D Earth model to better loca... With dense seismic arrays and advanced imaging methods, regional three-dimensional (3D) Earth models have become more accurate. It is now increasingly feasible and advantageous to use a 3D Earth model to better locate earthquakes and invert their source mechanisms by fitting synthetics to observed waveforms. In this study, we develop an approach to determine both the earthquake location and source mechanism from waveform information. The observed waveforms are filtered in different frequency bands and separated into windows for the individual phases. Instead of picking the arrival times, the traveltime differences are measured by cross-correlation between synthetic waveforms based on the 3D Earth model and observed waveforms. The earthquake location is determined by minimizing the cross-correlation traveltime differences. We then fix the horizontal location of the earthquake and perform a grid search in depth to determine the source mechanism at each point by fitting the synthetic and observed waveforms. This new method is verified by a synthetic test with noise added to the synthetic waveforms and a realistic station distribution. We apply this method to a series of Mw3.4-5.6 earthquakes in the Longmenshan fault (LMSF) zone, a region with rugged topography between the eastern margin of the Tibetan plateau and the western part of the Sichuan basin. The results show that our solutions result in improved waveform fits compared to the source parameters from the catalogs we used and the location can be better constrained than the amplitude-only approach. Furthermore, the source solutions with realistic topography provide a better fit to the observed waveforms than those without the topography, indicating the need to take the topography into account in regions with rugged topography. 展开更多
关键词 source mechanism inversion seismic location 3D strain Green's tensors Tibetan plateau TOPOGRAPHY
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GoTa Digital Trunking System and It's Location Service
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作者 Wu Shiyong (CDMA Division of ZTE Corporation,Nanjing 210012,China) 《ZTE Communications》 2004年第2期36-38,共3页
1 GoTa System Features andLocation Service1.1 GoTaGoTa, the abbreviation of“Global OpenTrunking Architecture”, is anew-generation digital trunkingcommunication system based on theCDMA2000 1x technology. It makes use... 1 GoTa System Features andLocation Service1.1 GoTaGoTa, the abbreviation of“Global OpenTrunking Architecture”, is anew-generation digital trunkingcommunication system based on theCDMA2000 1x technology. It makes use of manyadvantages of the CDMA technology and makesimprovement and optimization for the digitaltrunking communication system. It cansimultaneously realize multipte services including 展开更多
关键词 GoTa Digital Trunking system and It’s location service CDMA ZTE GsM
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基于同步挤压S变换的谐振接地系统单相接地故障区段定位方法
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作者 权立 颜琬滢 +2 位作者 王毅钊 侯泽权 蒋劲轩 《电网与清洁能源》 CSCD 北大核心 2024年第10期59-66,共8页
谐振接地系统单相接地的故障特征微弱,故障区段难以定位。根据健全与故障区段电流低频能量差异大的特点,利用同步挤压S变换挤压、重组低频区段电流,增强故障特征辨识度;计算各区段能量比值,将能量比值最大的判为故障区段,提出基于同步挤... 谐振接地系统单相接地的故障特征微弱,故障区段难以定位。根据健全与故障区段电流低频能量差异大的特点,利用同步挤压S变换挤压、重组低频区段电流,增强故障特征辨识度;计算各区段能量比值,将能量比值最大的判为故障区段,提出基于同步挤压S变换的故障区段定位方法。以全频区段电流重组信号的峭度因子构建保护启动判据。不同故障条件影响下,大量PSCAD仿真测试了所提启动和区段定位方法的性能及可行性,现场数据验证了所提方法的有效性。 展开更多
关键词 谐振接地系统 故障区段定位 单相接地故障 同步挤压s变换
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Location Attractiveness as a Major Factor in Museum Visitors'Choice and Satisfaction
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作者 Federica Codignola 《Management Studies》 2017年第2期75-90,共16页
This paper is intended to give a contribution to the debate on the functional relationship between the museum and the local territory; more specifically, the aim of this study is to understand the role of a museum loc... This paper is intended to give a contribution to the debate on the functional relationship between the museum and the local territory; more specifically, the aim of this study is to understand the role of a museum location in attracting visitors and influencing their processes of choice and satisfaction. The study follows, in particular, a previous study conducted by Mariani and Mussini (2013) based on Fondazione di Venezia data, with a view to better contextualization level. Previous studies have examined the role of museums in enhancing the image of a destination and in attracting and conveying additional tourists' fluxes, arguing that although not all museums are a destination of choice for visitors, a great museum or a strong exhibition program still does represent a national and international attraction. This paper overturns this argument investigating whereas an appealing location (such as a tourist destination) can influence prospective visitors about the level of attractiveness of a pay cultural event taking place therein. A questionnaire was developed and data were collected at the Palazzo Ducale in Venice, Italy, in 2007, during the art exhibition "Venezia e l'Islam 829-1797", via 501 face-to-face visitors interviews. The research model analyzes data through the conjoint analysis and the descriptive statistics. Results show that the exhibition location has been a relevant factor in influencing the visitors' decision process linked to the attendance of the event. Data show that, for the majority of visitors, the exhibition had been located elsewhere, they would not have visited it. Thus, an appealing location or a structured tourist destination may function as an attractive platform that may contribute to enforce the overall visitor's satisfaction with regard to his or her attendance to a cultural event. Furthermore, such a fact depends on specific objective variables (e.g., level of education, age), although no significant differences were reported between segments based on other socio-demographic characteristics such as sex. To conclude, arts and cultural managers should market and position cultural events in locations that can function as attractive, thus as emotionally driven experience consumption sites. Furthermore, they should consider both the cognitive and the emotional aspects of visitor's experience when designing and planning their events, as well as when assessing visitor's satisfaction. Cognitive and emotional aspects should be considered simultaneously when measuring visitors' satisfaction. In shaping visitors' satisfaction, emotions, such as the pleasure to be in a particular location, are more significant than cognitive aspects, such as the theme of the exhibition. 展开更多
关键词 cultural management arts management museum management cultural event museum attendance visitor's satisfaction location attractiveness conjoint analysis
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Location Optimization of a Coal Power Plant to Balance Costs against Plant’s Emission Exposure
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作者 Najam Khan Ekaterina Koromyslova 《American Journal of Operations Research》 2019年第1期31-58,共28页
The goal of the research is to develop a methodology to minimize the public’s exposure to harmful emissions from coal power plants while maintaining minimal operational costs related to electric distribution losses a... The goal of the research is to develop a methodology to minimize the public’s exposure to harmful emissions from coal power plants while maintaining minimal operational costs related to electric distribution losses and coal logistics. The objective is achieved by combining EPA Screen3, ISC3 and Japanese METI-LIS model equations with minimum spanning tree (MST) algorithm. Prim’s MST algorithm is used to simulate an electric distribution system and coal transportation pathways. The model can detect emission interaction with another source and estimate the ground level concentrations of emissions up to distances of 25 kilometers. During a grid search, the algorithm helps determine a candidate location, for a new coal power plant, that would minimize the operational cost while ensuring emission exposure is below the EPA/NIOSH thresholds. The proposed methodology has been coded in form of a location analysis simulation. An exhaustive search strategy delivers a final candidate location for a new coal power plant to ensure minimum operational costs as compared to the random or greedy search strategy. The simulation provides a tool to industrial zone planners, environmental engineers, and stakeholders in coal-based power generation. Using operational and emissions perspectives, the tool helps ascertain a list of compromise locations for a new coal power plant facility. 展开更多
关键词 MCDA-Operations Research location Analysis Prim’s Algorithm ATMOsPHERIC POLLUTION Modelling TRANsPORTATION Cost
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Rough Set Theory Based Map Matching Scheme for Mobile Location System
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作者 Ruyun Zhang Peng Li Shanshan Wang 《通讯和计算机(中英文版)》 2010年第3期39-43,共5页
关键词 移动定位系统 粗糙集理论 地图匹配 统计 移动用户 无线网络 道路驾驶 数据通信
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