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基于全面量测的透明配电网数据化运维技术研究 被引量:1
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作者 彭依明 黄春艳 杨晨雨 《机电工程技术》 2023年第6期217-221,共5页
目前配电网存在数据采集不全、设备状态不可见、运维困难的问题。为此,在剖析透明配电网的概念及其3个基本特征的基础上,设计一款集成度高、应用范围广的数据采集终端,可用于各类配电设备的信息采集和通信。提出一种透明配电网的数据化... 目前配电网存在数据采集不全、设备状态不可见、运维困难的问题。为此,在剖析透明配电网的概念及其3个基本特征的基础上,设计一款集成度高、应用范围广的数据采集终端,可用于各类配电设备的信息采集和通信。提出一种透明配电网的数据化运维平台架构和实现模式,覆盖基础层、数据层、应用层与客户端4个层级,可支撑配电网运行数据从采集到分析到应用的全过程流转。结果表明:通过分析利用运行数据,透明配电网可以实现智能运维和辅助决策,可有效提升配电网的运维效率和管理水平。 展开更多
关键词 全面 透明配电网 数据化 运维 数据采集终端
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烽火通信显露锋芒,全面领跑FTTH市场
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《通信世界》 2007年第35期12-12,共1页
烽火通信凭借一大批颇具影响力的FTTH商用工程积累,市场占有率和品牌影响力均居行业首位,已成为FTTH市场的领跑者。
关键词 烽火通信 市场占有率 中国电信 品牌影响力 规模部署 广东电信 行业标准 北京通信 武汉电信 全面测
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The Isospectrum Problem of Compact Hypersurfaces on a Sphere
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作者 徐森林 庞华栋 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期1-6,共6页
In this paper, we discuss the isospectrum of totally umbilical hypersurfaces with totally geodesic hypersurfaces on a sphere.
关键词 ISOSPECTRUM totally umbilical hypersurface totally geodesic hypersurface
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Climate warming and sea level rise
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作者 岳军 Dong YUE +2 位作者 吴桑云 耿秀山 赵长荣 《Marine Science Bulletin》 2012年第1期28-41,共14页
Based on a large number of actual data, the author believe that the modem global warming and sea level rise resulted from climate warming after the cold front of the Little Ice Age about 200 years ago and the developm... Based on a large number of actual data, the author believe that the modem global warming and sea level rise resulted from climate warming after the cold front of the Little Ice Age about 200 years ago and the developmnet of the sea level rise phase. In the past 30 years, the rate of sea level rise was increasing, which is under the background of the average temperature uplift 0.2F°(0.11℃)every 10 years in succession from the 1980s to the past 10 years this century. On the basis of the absolute and relative sea-level rise rate that was calculated from the tidal data during the same period at home and abroad in the last 30 years, in accordance with the resolutions of the 2010 climate conference in Cancun, at the same time, considering the previous prediction and research, the world's sea levels and the relative sea level in Tianjin, Shanghai, Dongying, Xiamen, Haikou and other coastal cities that have severe land subsidence in 2050 and 2100 are calculated and evaluated. 展开更多
关键词 global warming sea level rise RATE PREDICTION EVALUATION
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An Effective Long String Searching Algorithm towards Component Security Testing 被引量:2
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作者 Jinfu Chen Lili Zhu +4 位作者 Zhibin Xie Michael Omari Hilary Ackah-Arthur Saihua Cai Rubing Huang 《China Communications》 SCIE CSCD 2016年第11期153-169,共17页
In the execution of method invocation sequences to test component security,abnormal or normal information is generated and recorded in a monitor log. By searching abnormal information from monitor log,the exceptions t... In the execution of method invocation sequences to test component security,abnormal or normal information is generated and recorded in a monitor log. By searching abnormal information from monitor log,the exceptions that the component has can be determined. To facilitate the searching process,string searching methods could be employed. However,current approaches are not effective enough to search long pattern string. In order to mine the specific information with less number of matches,we proposed an improved Sunday string searching algorithm in this paper. Unlike Sunday algorithm which does not make use of the already matched characters,the proposed approach presents two ideas — utilizing and recycling these characters. We take advantage of all matched characters in main string,if they are still in the matchable interval compared with pattern string,to increase the distance that pattern string moves backwards. Experimental analysis shows that,compared to Sunday algorithm,our method could greatly reduce the matching times,if the scale of character set constituting both main string and pattern string is small,or if the length of pattern string is long. Also,the proposed approach can improve the search effectiveness for abnormal information in component security testing. 展开更多
关键词 component testing security detection monitor log abnormal information string-searching
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肿瘤突变负荷在EGFR突变型晚期非小细胞肺癌中的临床研究进展 被引量:3
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作者 何夕 焦晓栋 臧远胜 《中国癌症杂志》 CAS CSCD 北大核心 2021年第1期69-75,共7页
表皮生长因子受体(epidermal growth factor receptor,EGFR)-酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)的应用使EGFR突变型非小细胞肺癌(non-small cell lung cancer,NSCLC)患者的生存显著改善,但仍有部分患者疗效及预后不佳,... 表皮生长因子受体(epidermal growth factor receptor,EGFR)-酪氨酸激酶抑制剂(tyrosine kinase inhibitor,TKI)的应用使EGFR突变型非小细胞肺癌(non-small cell lung cancer,NSCLC)患者的生存显著改善,但仍有部分患者疗效及预后不佳,寻求预测此类患者疗效及预后的标志物迫在眉睫。肿瘤突变负荷(tumor mutational burden,TMB)前期主要应用于免疫治疗获益人群的筛选及疗效预测,近期在EGFR突变型NSCLC中也有相应的探索性研究。就TMB的检测与挑战及其在EGFR突变型晚期NSCLC中的最新应用研究进展进行综述。 展开更多
关键词 非小细胞肺癌 肿瘤突变负荷 表皮生长因子受体 二代 全面基因组 预后
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A Dataset of Global Ocean Surface Currents for 1999-2007 Derived from Argo Float Trajectories: A Comparison with Surface Drifter and TAO Measurements 被引量:6
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作者 XIE Jiping ZHU Jiang 《Atmospheric and Oceanic Science Letters》 2009年第2期97-102,共6页
A dataset of surface current vectors with error estimate from 1999 to 2007 is derived from the trajectories of the Array for Real-time Geostrophic Oceanography (Argo) drifting on surface over the global ocean. The err... A dataset of surface current vectors with error estimate from 1999 to 2007 is derived from the trajectories of the Array for Real-time Geostrophic Oceanography (Argo) drifting on surface over the global ocean. The error of the estimated surface currents is about 4.7 cm s-1 which is equivalent to the accuracy of the currents determined from the surface drifters. Geographically, the Argo-derived surface currents can fill many gaps left by the Global Drifter Program due to the greater number of floats, and can provide a complementary in situ observational system for monitoring global ocean surface currents. The surface currents from the Argo floats are compared with the surface drifter-derived currents and the Tropical Atmosphere Ocean program (TAO) measurements. The comparisons show good agreement for both the current amplitude and the direction of surface currents. Results indicate the feasibility of obtaining ocean surface currents from the Argo array and of combining the surface currents from Argo and the ocean surface drifters for in situ mapping of the global surface currents. The authors also make the dataset available to users of interest for many types of applications. 展开更多
关键词 surface currents Argo floats the Tropical Atmosphere Ocean program surface drifter
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Allowance of Lateral Breakthrough Error for Super Long Tunnels from 20km to 50km
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作者 ZHANGZhenglu ZHANGSonglin 《Geo-Spatial Information Science》 2004年第3期198-203,共6页
Up to now there is no specification about the allowance of lateral breakthrough error for super long tunnel from 20 km to 50 km. On the basis of the design of GPS networks located outside and inside tunnel traverse ne... Up to now there is no specification about the allowance of lateral breakthrough error for super long tunnel from 20 km to 50 km. On the basis of the design of GPS networks located outside and inside tunnel traverse network, we propose a method for calculating the influence value caused by control surveying errors. Through a lot of simulative calculations and combination with piercing practice of super tunnels in Wan Jiazai Project, Shanxi province, we present an allowance table of lateral breakthrough error for super long tunnels from 20 km to 50 km. 展开更多
关键词 super long tunnel lateral breakthrough error ALLOWANCE
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A new forecast model for the carbon-monoxide concentration in the upper corner of mining face 被引量:2
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作者 DENG Jun ZHAI Xiao-wei YAN Zheng-xin 《Journal of Coal Science & Engineering(China)》 2011年第1期39-42,共4页
The CO gas in the upper comer along with the work of mining face in different coal-seam of Lingwu coal-field has deeply affected judgment for the degree of the coal spontaneous combustion and safety work. For this iss... The CO gas in the upper comer along with the work of mining face in different coal-seam of Lingwu coal-field has deeply affected judgment for the degree of the coal spontaneous combustion and safety work. For this issue, a new calculation and forecast model of the carbon monoxide concentration in the upper comer of mining face was deduced for analyzing and calculating the date from the lab and test-in-place, during this course using the knowledge of heat transfer, fluid dynamics, and mathematics. The model took into account the characteristics of the coal spontaneous combustion, coal mining conditions, and other correlate factors, so the CO concentration of the upper comer safe under the normal condition, and it is in danger when the coal reached spontaneous combustion, which can be calculated accurately with the model and compared with the measured concentration with a tolerance of less than 12%. 展开更多
关键词 spontaneous combustion of coal carbon monoxide "three zone" in gob
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Development of an automated system for continuous monitoring of powered roof support in longwall panel 被引量:1
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作者 ATULKumar DHEERAJKumar +1 位作者 SINGHU.K. GUPTAP.S. 《Journal of Coal Science & Engineering(China)》 2010年第4期337-340,共4页
Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a po... Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a powered support in a mechanized Iongwall sublevel caving face. The logging system can be programmed for logging the data from the sensors at different logging intervals ranging from 16 h to 1 ms for logging variation in hydraulic pressures in legs and convergence of the support during progressive face advance. For recording dynamic loads, the data logger can be programmed to start fast logging, say at 10 ms intervals, when the pressure in a leg reaches a pre-specified threshold value, and continue fast logging until the pressure drops below this threshold value. This fast logging automatically stops when the pressure drops below this threshold value. 展开更多
关键词 data logging system CONVERGENCE leg pressure software analysis
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Detection of Total Phenols, Essential and Toxic Elements in Latvian Whole Grain Bread
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作者 Natalia Bobere Anton Podjava Ida Jakobsone 《Journal of Chemistry and Chemical Engineering》 2012年第1期1-6,共6页
A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flo... A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (ETAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD 5 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation. 展开更多
关键词 Essential and toxic elements whole grain bread flame photometry FAAS ETAA total phenols spectrophotometry.
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PIV Studies on Turbulence Structure in Air/Water Interface with Wind-Induced Water Waves
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作者 M. Sanjou, I. Nezu A. Toda 《Journal of Energy and Power Engineering》 2011年第11期1063-1067,共5页
When wind appears over the free surface, water waves and turbulence are generated by an interfacial shear stress. In particular, turbulent diffusion promotes significantly mass and momentum transport beneath the inter... When wind appears over the free surface, water waves and turbulence are generated by an interfacial shear stress. In particular, turbulent diffusion promotes significantly mass and momentum transport beneath the interface between the water and air significantly in ocean and lakes, and thus it is very important for global environment problems to reveal such turbulence property and coherent structure. Simultaneous measurements of velocities and free-surface elevation allow us to conduct reasonably the phase analysis of the coherent structure in interfacial shear layer. Furthermore, multi-point measurements such as PIV are very powerful to detect the space-time structure of coherent motions. Therefore, in the present study, we developed a specially designed PIV system which can measure the velocity components and surface-elevation fluctuation simultaneously by using two sets of high-speed cameras to reveal the coherent structure in the interfacial shear layer. 展开更多
关键词 Air/water interface wind-induced water waves PIV measurements.
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C_∞ Compactness for Minimal Submanifolds in the Unit Sphere 被引量:1
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作者 徐森林 梅加强 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第2期191-198,共8页
In this paper we study the C3 compactness for minimal submanifolds in the unit sphere. We obtain two compactness theorems. As an application, we prove that there is a positive number δ(n), such that if the square of ... In this paper we study the C3 compactness for minimal submanifolds in the unit sphere. We obtain two compactness theorems. As an application, we prove that there is a positive number δ(n), such that if the square of the length of the second fundamental form of a minimal subrnanifold in the unit sphere is less than 2n/3+δ(n), it must be totally geodesic or diffeomorphic to a Veronese surface. 展开更多
关键词 minimal submanifold totally geodesic compactness theorem.
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The Effects of Explicit Metapragmatic Instruction on Chinese English Language Learners' Acquisition of Compliment Responses
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作者 ZHOU Wen DENG Jun 《Chinese Journal of Applied Linguistics》 SCIE 2017年第2期167-180,229,共15页
The present study investigated the effects of explicit metapragmatic instruction on foreign language learners' performance of compliment responses (CRs). Eighty-two non-English major students participated in this s... The present study investigated the effects of explicit metapragmatic instruction on foreign language learners' performance of compliment responses (CRs). Eighty-two non-English major students participated in this study. They were randomly assigned to two groups, an experimental group that received explicit metapragmatic instruction on compliment responses and a control group that did not. A pretest-posttest research design was adopted. The data were collected through a written discourse completion task (WDCT) with six scenarios concerning the topics of appearance, performance, and personality. The results revealed that learners who received explicit instruction dramatically decreased their use of Accept strategy and increased Combination (CB) strategy at the macro level; more specifically, a decrease in Appreciation and an increase in Accept + Accept at the micro level. The learners of the control group made little progress in their performance. The study sheds light on pragmatics learning in an EFL setting and provides implications for pragmatics pedagogy. 展开更多
关键词 compliment response explicit metapragmatic instruction written discourse completion task
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Ocean surface wave measurements from fully polarimetric SAR imagery 被引量:6
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作者 XIE Tao William PERRIE +4 位作者 HE YiJun LI HaiYan FANG He ZHAO ShangZhuo YU WenJin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第10期1849-1861,共13页
A new method for the retrieval of ocean wave parameters from SAR imagery is developed,based on the shape-from-shading(SFS)technique.Previously,the SFS technique has been used in the reconstruction of 3D landform infor... A new method for the retrieval of ocean wave parameters from SAR imagery is developed,based on the shape-from-shading(SFS)technique.Previously,the SFS technique has been used in the reconstruction of 3D landform information from SAR images,in order to generate elevation maps of topography for land surfaces.Here,in order to retrieve ocean wave characteristics,we apply the SFS methodology,together with a method to orient the angular measurements of the azimuth slope and range slope,in the measurement of ocean surface waves.This method is applied to high resolution fine-quad polarization mode(HH,VV,VH and HV)C-band RADARSAT-2 SAR imagery,in order to retrieve ocean wave spectra and extract wave parameters.Collocated in situ buoy measurements are used to validate the reliability of this method.Results show that the method can reliably estimate wave height,dominant wave period,dominant wave length and dominant wave direction from C-band SAR images.The advantage of this method is that it does not depend on modulation transfer functions(MTFs),in order to measure ocean surface waves.This method can be used in monitoring ocean surface wave propagation through open water areas into ice-covered areas,especially the marginal ice zone(MIZ)in polar oceans. 展开更多
关键词 polarimetric SAR imagery ocean surface wave shape from shading
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Seatbelt paths of the pregnant women sitting in the rear seat of a motor vehicle
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作者 Masahito Hitosugi Takeshi Koseki +3 位作者 Yuka Kinugasa Tomokazu Hariya Genta Maeda Yasuki Motozawa 《Chinese Journal of Traumatology》 CAS CSCD 2017年第6期343-346,共4页
Purpose: Seatbelt use during pregnancy is important to improve maternal and fetal survival after motor vehicle collisions. However, because the rear seatbelt of a motor vehicle tends to make contact with the neck, ev... Purpose: Seatbelt use during pregnancy is important to improve maternal and fetal survival after motor vehicle collisions. However, because the rear seatbelt of a motor vehicle tends to make contact with the neck, even if it is adequately used, some pregnant women sitting in the rear seat opt not to fasten the belt. The purpose of this study is to explore seatbelt-neck contact for pregnant women sitting in the rear seat of a motor vehicle. Methods: We carried out an anthropometric study. Japanese women who were _〉30 weeks pregnant (n = 12) sat in the left side of the rear seat of a typical mid-size passenger sedan and fastened the seatbelt. Seating posture was investigated by measuring the coordinates of the anthropometric data points of the pregnant women (head, shoulder, hip joint, and knee joint). The belt path was analyzed by measuring the clearance between the belt and the sternum or navel. Results: Among the 12 pregnant women at 33.9 week _+ 3.3 week gestation, the shoulder belt deviated to the right side and subsequently contacted to the neck in four pregnant women (Contact group). The height of the Contact group was significantly shorter than that of Non-contact group (152.3 cm ~ 3.0 cm vs. 159.0 cm + 3.3 cm, p = 0.008). Regarding the relative position of the seatbelt to the subject's body, the distances from the top of the sternum to the center of the shoulder belt were significantly shorter in Contact group (3.9 cm ~ 3.5 cm) than that in the Non-contact group (8.0 cm ~ 1.6 cm, p = 0.03). However, no significant difference was found for the distance from the umbilicus to the center of the lap belt. Conclusion: Our findings show that because of short height and late term of pregnancy with protrusion of the abdomen, the shoulder belt deviates to the right or left, avoiding the protruded uterus, and subsequently makes contact with the neck. Seatbelt systems for rear seats need to be developed to improve passenger safety, especially for pregnant women. 展开更多
关键词 Pregnant women Rear seat Seatbelt ANTHROPOMETRY Motor vehicles
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ON A CONJECTURE OF K. OGIUE FOR KAEHLER HYPERSURFACES
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作者 SHANG WEIMING 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1994年第1期69-74,共6页
An affirmative answer to a conjecture of K. Ogiue formulated in [2] is given, namely, thefollowing result is proved:Let Ma (n ≥ 2) be a complete Kaehler hypersurface immersed in a complex projective spaceCPn+1. Ifeve... An affirmative answer to a conjecture of K. Ogiue formulated in [2] is given, namely, thefollowing result is proved:Let Ma (n ≥ 2) be a complete Kaehler hypersurface immersed in a complex projective spaceCPn+1. Ifevery sectional curvature of Mn is positive, then Mn is totally geodesic in CPn+1. 展开更多
关键词 Kaehler hypersurfaces Conjecture of K. Ogiue Sectional curvature.
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