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Analysis on Structural Control of Coal Distribution in the Northern Qaidam Basin,NW China 被引量:3
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作者 LIU Tianji WANG Tong ZHAN Wenfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期690-696,共7页
The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coa... The distribution of the Jurassic coal measures in the northern Qaidam Basin is obviously controlled by the regional structures. Based on the existing data of coalfield exploration and combined with the analysis of coalfield basement structures, features of the main faults, and the distribution of coal measures, this paper brings forward a scheme of coalfield tectonic divisional units and the definition of the coal-controlling structural styles in the northern Qaidam Basin. The structure control of the distribution of coal measures is further discussed. Several stages of regional tectonic activities since the Indosinian has led to the distribution of coal measures into the characteristics of zonation from the north to south and block from east to west. The results indicate that the structural deformations are the most intense in the front of the three uplifted belts, which are characterized by the combination of thrusts. The coal measures are uplifted to the shallow formations, and are easy to be exploited, but the scale of mines is small because of serious damages by the coal distribution. On the contrary, the stress and strain are weak in the three depressions, with the coal-controlling structural styles being mainly the thrust-fold and thrust-monocline combinations. The distribution of coals in the depressions is relatively stable. The shallower part of the depression will become the key areas for exploration and development of coal resources in the northern Qaidam Basin. 展开更多
关键词 northern Qaidam Basin tectonic units coal-controlling structural styles distribution regularity of coal measures
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A multi-sensor-based distributed real-time measurement system for glacier deformation
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作者 DONG Han-chuan LIU Shuang +4 位作者 PANG Li-li TAO Zhi-gang FANG Li-de ZHANG Zhong-hua LI Xiao-ting 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2913-2927,共15页
Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this stud... Glacier disasters occur frequently in alpine regions around the world,but the current conventional geological disaster measurement technology cannot be directly used for glacier disaster measurement.Hence,in this study,a distributed multi-sensor measurement system for glacier deformation was established by integrating piezoelectric sensing,coded sensing,attitude sensing technology and wireless communication technology.The traditional Modbus protocol was optimized to solve the problem of data identification confusion of different acquisition nodes.Through indoor wireless transmission,adaptive performance analysis,error measurement experiment and landslide simulation experiment,the performance of the measurement system was analyzed and evaluated.Using unmanned aerial vehicle technology,the reliability and effectiveness of the measurement system were verified on the site of Galongla glacier in southeastern Tibet,China.The results show that the mean absolute percentage errors were only 1.13%and 2.09%for the displacement and temperature,respectively.The distributed glacier deformation real-time measurement system provides a new means for the assessment of the development process of glacier disasters and disaster prevention and mitigation. 展开更多
关键词 Glacier disasters Distributed deformation measurement MULTI-SENSOR REAL-TIME LoRa Data adaptive.
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A distributed measurement method for in-situ soil moisture content by using carbon-fiber heated cable 被引量:13
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Guangqing Wei Shen-En Chen Junfan Yan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第6期700-707,共8页
Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a ... Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a distributed measurement system for in-situ soil moisture content (SM-DTS) is introduced.The system is based on carbon-fiber heated cable (CFHC) technology that has been developed to enhancethe measuring accuracy of in-situ soil moisture content. Using CFHC technique, a temperature characteristicvalue (Tt) can be defined from temperatureetime curves. A relationship among Tt, soil thermalimpedance coefficient and soil moisture content is then established in laboratory. The feasibility of theSM-DTS technology to provide distributed measurements of in-situ soil moisture content is verifiedthrough field tests. The research reported herein indicates that the proposed SM-DTS is capable ofmeasuring in-situ soil moisture content over long distances and large areas. 展开更多
关键词 In-situ soil moisture content Distributed measurement Carbon-fiber heated cable (CFHC) Fiber-optic sensing
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Performance evaluation of two types of heated cables for distributedtemperature sensing-based measurement of soil moisture content 被引量:7
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Kun Zhu Guangqing Wei Kai Gu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第2期212-217,共6页
Distributed temperature sensing(DTS)using heated cables has been recently developed for distributed monitoring of in-situ soil moisture content.In this method,the thermal and electrical properties of heated cables hav... Distributed temperature sensing(DTS)using heated cables has been recently developed for distributed monitoring of in-situ soil moisture content.In this method,the thermal and electrical properties of heated cables have a significant influence on the measurement accuracy of soil moisture content.In this paper,the performances of two heated cables,i.e.the carbon-fiber heated cable(CFHC)and the metalnet heated cable(MNHC),are studied in the laboratory.Their structures,uniformity in the axial direction,measurement accuracy and suitability are evaluated.The test results indicate that the MNHC has a better uniformity in the axial direction than CFHC.Both CFHC and MNHC have high measurement accuracy.The CFHC is more suitable for short-distance measurement(500 m),while the MNHC can be used for longdistance measurement(>500 m). 展开更多
关键词 Soil moisture content Carbon-fiber heated cable(CFHC) Metal-net heated cable(MNHC) Distributed measurement Optical fiber
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Distributed sampling measurement method of network traffic in high-speed IPv6 networks
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作者 Pan Qiao Pei Changxing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期835-840,共6页
With the advent of large-scale and high-speed IPv6 network technology, an effective multi-point traffic sampling is becoming a necessity. A distributed multi-point traffic sampling method that provides an accurate and... With the advent of large-scale and high-speed IPv6 network technology, an effective multi-point traffic sampling is becoming a necessity. A distributed multi-point traffic sampling method that provides an accurate and efficient solution to measure IPv6 traffic is proposed. The proposed method is to sample IPv6 traffic based on the analysis of bit randomness of each byte in the packet header. It offers a way to consistently select the same subset of packets at each measurement point, which satisfies the requirement of the distributed multi-point measurement. Finally, using real IPv6 traffic traces, the conclusion that the sampled traffic data have a good uniformity that satisfies the requirement of sampling randomness and can correctly reflect the packet size distribution of full packet trace is proved. 展开更多
关键词 network measurement traffic sampling IPV6 distributed measurement Shannon entropy
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Research on Collaboration Theory of Distributed Measurement System and Real-Time of Communication Platform
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作者 SHENYan 《Journal of Electronic Science and Technology of China》 2005年第1期95-95,共1页
关键词 distributed measurement system agent technology swarm intellgence Particle Swarm Optimization algorithm Collaboration model Switched Ethernet Real-time Scheduling AEROENGINE
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On-board measurement of particle numbers and their size distribution from a light-duty diesel vehicle:Influences of VSP and altitude 被引量:12
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作者 Jia Liu Yunshan Ge +6 位作者 Xin Wang Lijun Hao Jianwei Tan Zihang Peng Chuanzhen Zhang Huiming Gong Ying Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第7期238-248,共11页
In this study,the particle size-resolved distribution from a China-3 certificated light-duty diesel vehicle was measured by using a portable emission measurement system(PEMS).In order to examine the influences of ve... In this study,the particle size-resolved distribution from a China-3 certificated light-duty diesel vehicle was measured by using a portable emission measurement system(PEMS).In order to examine the influences of vehicle specific power(VSP) and high-altitude operation,measurements were conducted at 8 constant speeds,which ranged from 10 to 80 km/hr at10 km/hr intervals,and two different high altitudes,namely 2200 and 3200 m.The results demonstrated that the numbers of particles in all size ranges decreased significantly as VSP increased when the test vehicle was running at lower speeds(〈 20 km/hr),while at a moderate speed(between 30 and 60 km/hr),the particle number was statistically insensitive to increase VSP.Under high-speed cruising conditions,the numbers of ultrafine particles and PM2.5were insensitive to changes in VSP,but the numbers of nanoparticles and PM10 surged considerably.An increase in the operational altitude of the test vehicle resulted in increased particle number emissions at low and high driving speeds;however,particle numbers obtained at moderate speeds decreased as altitude rose.When the test vehicle was running at moderate speeds,particle numbers measured at the two altitudes were very close,except for comparatively higher number concentrations of nanoparticles measured at 2200 m. 展开更多
关键词 On-board measurement Particle number Size distribution Diesel VSP High altitude
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Vertical distribution of aerosol optical properties based on aircraft measurements over the Loess Plateau in China 被引量:6
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作者 Junxia Li Xingang Liu +9 位作者 Liang Yuan Yan Yin Zhanqing Li Peiren Li Gang Ren Lijun Jin Runjun Li Zipeng Dong Yiyu Li Junmei Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第8期44-56,共13页
Vertical distributions of aerosol optical properties based on aircraft measurements over the Loess Plateau were measured for the first time during a summertime aircraft campaign, 2013 in Shanxi, China. Data from four ... Vertical distributions of aerosol optical properties based on aircraft measurements over the Loess Plateau were measured for the first time during a summertime aircraft campaign, 2013 in Shanxi, China. Data from four flights were analyzed. The vertical distributions of aerosol optical properties including aerosol scattering coefficients(σsc), absorption coefficients(σab),Angstr?m exponent(α), single scattering albedo(ω), backscattering ratio(βsc), aerosol mass scattering proficiency(Q sc) and aerosol surface scattering proficiency(Q sc′) were obtained. The mean statistical values of σsc were 77.45 Mm-1(at 450 nm), 50.72 Mm-1(at 550 nm), and32.02 Mm-1(at 700 nm). The mean value of σab was 7.62 Mm-1(at 550 nm). The mean values ofα, βsc and ω were 1.93, 0.15, and 0.91, respectively. Aerosol concentration decreased with altitude. Most effective diameters(ED) of aerosols were less than 0.8 μm. The vertical profiles of σsc,, α, βsc, Q sc and Q sc′ showed that the aerosol scattering properties at lower levels contributed the most to the total aerosol radiative forcing. Both α and βsc had relatively large values, suggesting that most aerosols in the observational region were small particles. The mean values of σsc, α, βsc, Q sc, Q sc′, σab and ω at different height ranges showed that most of the parameters decreased with altitude. The forty-eight hour backward trajectories of air masses during the observation days indicated that the majority of aerosols in the lower level contributed the most to the total aerosol loading, and most of these particles originated from local or regional pollution emissions. 展开更多
关键词 Vertical distribution Optical properties Aircraft measurements The Loess Plateau
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Investigation of the heat distribution in dry friction systems during fade and recovery using fiber-optic sensing and infrared technology
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作者 Albert ALBERS Thomas KLOTZ +1 位作者 Chris FINK Sascha OTT 《Friction》 SCIE EI CAS CSCD 2022年第3期422-435,共14页
The design of dry-running friction pairings and systems determines not only their installation space and costs,but also their reliability under critical load conditions,for example in emergencies,in the case of faults... The design of dry-running friction pairings and systems determines not only their installation space and costs,but also their reliability under critical load conditions,for example in emergencies,in the case of faults,and in the event of misuse.While knowledge of the contact pattern is highly important for the development of clutches and brakes,the contact-related measurement of the temperature of these systems has not yet been solved in a satisfactory manner.Despite its importance,the temperature distribution has only been measured in a few studies.Typically,temperature measurements of complete clutches and brakes are carried out using thermocouples only.In this study,a new innovative test setup is presented.This setup is able to measure the heat distribution of the lining and the steel disk of a brake with high spatial resolution by means of fiber optic sensing technology and thermography.As a novelty,it enables measurement of the heat distribution and allows to correlate it with the fade and recovery behavior.Contrary to the expectations,the contact pattern is heterogeneous in circumferential direction.Possible causes are discussed using simulation results.Along with surface analysis,the new setup contributes to the investigation of the causes of fade and recovery. 展开更多
关键词 dry-running clutch and brake fade and recovery high-resolution spatial temperature distribution measurement
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Saturated Hydraulic Conductivity from Field Measurements Compared to Pedotransfer Functions in a Heterogeneous Arable Landscape 被引量:1
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作者 Florian Winter Markus Disse 《Journal of Earth Science》 SCIE CAS CSCD 2010年第6期923-930,共8页
A high degree of uncertainty with regard to soil parameterisation limits the significance of physically-based simulation of distributed flood control measures, which affect the runoff generation process, such as land-... A high degree of uncertainty with regard to soil parameterisation limits the significance of physically-based simulation of distributed flood control measures, which affect the runoff generation process, such as land-use changes or differing soil tillage practices. In this study, the soil measurement data from the hillslope scale at the Scheyern research farm were compared to demonstrate this uncertainty. To account for the spatial variability of soils in the investigation area of Scheyern, different approaches were applied to estimate soil hydraulic properties and saturated hydraulic conductivity, and were compared to field measurements 展开更多
关键词 hydraulic conductivity pedotransfer function hood infiltrometer UNCERTAINTY distributed flood control measures.
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Comparison of four scanning mobility particle sizers at the Fresno Supersite 被引量:2
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作者 John G. Watson Judith C. Chow +4 位作者 David A. Sodeman Douglas H. Lowenthal M.-C. Oliver Chang Kihong Park Xiaoliang Wang 《Particuology》 SCIE EI CAS CSCD 2011年第3期204-209,共6页
Size distributions of ambient aerosols at the Fresno Supersite were measured with four commercially available scanning mobility particle sizers (SMPS). TSI nano, TSI standard, Grimm, and MSP instruments were colloca... Size distributions of ambient aerosols at the Fresno Supersite were measured with four commercially available scanning mobility particle sizers (SMPS). TSI nano, TSI standard, Grimm, and MSP instruments were collocated at the Fresno Supersite and particle size distributions were measured continuously from August 18 through September 18, 2005. For particles with diameters between 10 and 200 nm, differences among hourly-average ambient particle concentrations ranged from 0% between the TSI nano and Grimm in the 30-50 nm size range to 39% between the Grimm and MSP in the 10-30 nm size range. MSP concentrations were 10-33% lower than those measured with the TSI standard for particles smaller than 200 nm. The TSI nano and TSI standard agreed to within 5% in their overlapping size range (10-84 nm). The TSI nano and Grimm agreed to within 40% for 5-10 nm particles. 展开更多
关键词 Aerosol measurement SMPS Fresno Supersite Size distribution Ultrafine particles
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Regional moment-independent sensitivity analysis with its applications in engineering 被引量:8
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作者 Changcong ZHOU Chenghu TANG +2 位作者 Fuchao LIU Wenxuan WANG Zhufeng YUE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1031-1042,共12页
Traditional Global Sensitivity Analysis(GSA) focuses on ranking inputs according to their contributions to the output uncertainty.However,information about how the specific regions inside an input affect the output ... Traditional Global Sensitivity Analysis(GSA) focuses on ranking inputs according to their contributions to the output uncertainty.However,information about how the specific regions inside an input affect the output is beyond the traditional GSA techniques.To fully address this issue,in this work,two regional moment-independent importance measures,Regional Importance Measure based on Probability Density Function(RIMPDF) and Regional Importance Measure based on Cumulative Distribution Function(RIMCDF),are introduced to find out the contributions of specific regions of an input to the whole output distribution.The two regional importance measures prove to be reasonable supplements of the traditional GSA techniques.The ideas of RIMPDF and RIMCDF are applied in two engineering examples to demonstrate that the regional moment-independent importance analysis can add more information concerning the contributions of model inputs. 展开更多
关键词 Cumulative distribution function Moment-independent Probability density function Regional importance measure Sensitivity analysis Uncertainty
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Temperature Field of PC Box Girder Bridge Based on GPRS Temperature Collection System
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作者 YANG Zeying LIU Jing +2 位作者 QU Jianbo ZHOU Xiangshan LI Lixin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第3期269-276,共8页
In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete(PC) curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote r... In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete(PC) curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote real-time temperature collection system to collect temperature data on site, and further uses the software ANSYS for analysis. Based on the comparisons between the measured data and the simulation results, the following conclusions can be drawn: 1 Our temperature monitoring system is reliable; 2 The corresponding measured data of the web plate and flange plate exposed to the sun, vary more severely than that at other positions, so these plates need higher standard design and construction requirements; 3 In the cold wave where still is sunshine, the box girder temperature effect behaves as sine-like curve. 展开更多
关键词 bridge engineering concrete curved box girder bridge temperature distribution and temperature effect measured data and finite element analysis
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