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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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Real-time reliability evaluation based on damaged measurement degradation data 被引量:16
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作者 王小林 蒋平 +1 位作者 郭波 程志君 《Journal of Central South University》 SCIE EI CAS 2012年第11期3162-3169,共8页
A method was proposed to evaluate the real-time reliability for a single product based on damaged measurement degradation data.Most researches on degradation analysis often assumed that the measurement process did not... A method was proposed to evaluate the real-time reliability for a single product based on damaged measurement degradation data.Most researches on degradation analysis often assumed that the measurement process did not have any impact on the product's performance.However,in some cases,the measurement process may exert extra stress on products being measured.To obtain trustful results in such a situation,a new degradation model was derived.Then,by fusing the prior information of product and its own on-line degradation data,the real-time reliability was evaluated on the basis of Bayesian formula.To make the proposed method more practical,a procedure based on expectation maximization (EM) algorithm was presented to estimate the unknown parameters.Finally,the performance of the proposed method was illustrated by a simulation study.The results show that ignoring the influence of the damaged measurement process can lead to biased evaluation results,if the damaged measurement process is involved. 展开更多
关键词 degradation analysis damaged measurement real-time reliability expectation maximization algorithm
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Micro-failure process and failure mechanism of brittle rock under uniaxial compression using continuous real-time wave velocity measurement 被引量:3
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作者 WU Zhi-jun WANG Zhi-yang +2 位作者 FAN Li-feng WENG Lei LIU Quan-sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期556-571,共16页
In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indi... In this study,the micro-failure process and failure mechanism of a typical brittle rock under uniaxial compression are investigated via continuous real-time measurement of wave velocities.The experimental results indicate that the evolutions of wave velocities became progressively anisotropic under uniaxial loading due to the direction-dependent development of micro-damage.A wave velocity model considering the inner anisotropic crack evolution is proposed to accurately describe the variations of wave velocities during uniaxial compression testing.Based on which,the effective elastic parameters are inferred by a transverse isotropic constitutive model,and the evolutions of the crack density are inversed using a self-consistent damage model.It is found that the propagation of axial cracks dominates the failure process of brittle rock under uniaxial loading and oblique shear cracks develop with the appearance of macrocrack. 展开更多
关键词 elastic wave velocity brittle rock failure uniaxial compression test continuous real-time measurement anisotropic damage evolution theory and modelling
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Real-time forward modeling and inversion of logging-while-drilling electromagnetic measurements in horizontal wells 被引量:2
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作者 WANG Lei LIU Yingming +2 位作者 WANG Caizhi FAN Yiren WU Zhenguan 《Petroleum Exploration and Development》 CSCD 2021年第1期159-168,共10页
Based on the pseudo-analytical equation of electromagnetic log for layered formation,an optimal boundary match method is proposed to adaptively truncate the encountered formation structures.An efficient integral metho... Based on the pseudo-analytical equation of electromagnetic log for layered formation,an optimal boundary match method is proposed to adaptively truncate the encountered formation structures.An efficient integral method is put forward to significantly accelerate the convergence of Sommerfeld integral.By asymptotically approximating and subtracting the first reflection/transmission waves from the scattered field,the new Sommerfeld integral method has addressed difficulties encountered by the traditional digital filtering method,such as low computational precision and limited operating range,and realized the acceleration of the computation speed of logging-while-drilling electromagnetic measurements(LWD EM).By making use of the priori information from the offset/pilot wells and interactively adjusting the formation model,the optimum initial guesses of the inversion model is determined in order to predict the nearby formation boundaries.The gradient optimization algorithm is developed and an interactive inversion system for the LWD EM data from the horizontal wells is established.The inverted results of field data demonstrated that the real-time interactive inversion method is capable of providing the accurate boundaries of layers around the wellbore from the LWD EM,and it will benefit the wellbore trajectory optimization and reservoir interpretation. 展开更多
关键词 logging-while-drilling electromagnetic measurement horizontal well real-time forward modeling interactive inversion bed boundary
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Real-Time Black Carbon Emissions from Light-Duty Passenger Vehicles Using a Portable Emissions Measurement System 被引量:1
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作者 Xuan Zheng Liqiang He +4 位作者 Xiaoyi He Shaojun Zhang Yihuan Cao Jiming Hao Ye Wu 《Engineering》 SCIE EI CAS 2022年第9期73-81,共9页
Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic... Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic BC.However,there are major uncertainties in the estimates of the BC emissions from on-road light-duty passenger vehicles(LDPVs),and results obtained with the portable emissions measurement system(PEMS)method are particularly lacking.We developed a PEMS platform and evaluated the on-road BC emissions from ten in-use LDPVs.We demonstrated that the BC emission factors(EFs)of gasoline direction injection(GDI)engine vehicles range from 1.10 to 1.56 mg.km^(-1),which are higher than the EFs of port fuel injection(PFI)engine vehicles(0.10–0.17 mg.km^(-1))by a factor of 11.The BC emissions during the cold-start phase contributed 2%–33%to the total emissions.A strong correlation(R^(2)=0.70)was observed between the relative BC EFs and average vehicle speed,indicating that traffic congestion alleviation could effectively mitigate BC emissions.Moreover,BC and particle number(PN)emissions were linearly correlated(R^(2)=0.90),and compared to PFI engine vehicles,the instantaneous PN-to-BC emission rates of GDI engine vehicles were less sensitive to vehicle specific power-to-velocity(VSPV)increase in all speed ranges. 展开更多
关键词 Black carbon Light-duty gasoline vehicles Portable emissions measurement system real-time emissions
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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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New development of hydraulic fracturing technique for in-situ stress measurement at great depth of mines 被引量:3
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作者 Meifeng Cai Hua Peng Hongguang Ji 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期665-670,共6页
In-situ stress measurement using the hydraulic fracturing technique was made at Wanfu Coal Mine in Shandong Province, China. To solve problems caused by great measuring depth and extra thick overburden soil layers in ... In-situ stress measurement using the hydraulic fracturing technique was made at Wanfu Coal Mine in Shandong Province, China. To solve problems caused by great measuring depth and extra thick overburden soil layers in the mine, a series of improved techniques were developed for the traditional hydraulic fracturing technique and equipment to increase their pressure-enduring ability and to ensure safe and flexible removal of the sealing packers with other experimental apparatus. Successful in-situ stress measurement at 37 points within 7 boreholes, which were mostly over 1000 m deep, was completed. Through the measurement, detailed information of in-situ stress state has been provided for mining design of the mine. The improved hydraulic fracturing technique and equipment also provide reliable tools for in-situ stress measurement at great depth of other mines. 展开更多
关键词 hydraulic fracturing in-situ stress measurement coal mine measuring depth
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Device interchangeability on anterior chamber depth and white-to-white measurements: a thorough literature review 被引量:13
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作者 Alberto Domínguez-Vicent Cari Pérez-Vives +2 位作者 Teresa Ferrer-Blasco Santiago García-Lázaro Robert Montés-Micó 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第7期1057-1065,共9页
We have reviewed a set of recently published studies that compared the anterior chamber depth(ACD) and/or white-to-white(WTW) distance obtained by means of different measuring devices.Since some of those studies r... We have reviewed a set of recently published studies that compared the anterior chamber depth(ACD) and/or white-to-white(WTW) distance obtained by means of different measuring devices.Since some of those studies reached contradictory conclusions regarding device interchangeability,this review was carried out in attempting to clarify which clinical devices can or cannot be considered as interchangeable in clinical practice to measure ACD and/or WTW distance,among these devices:A-scan,ultrasound biomicroscopy,Orbscan and Orbscan Ⅱ(Bausch&Lomb Surgical Inc.,San Dimas,California,USA),Pentacam and Pentacam HR(Oculus,Wetzlar,Germany),Galilei(Ziemer,Switzerland),Visante optical coherence tomography(Visante OCT,Carl Zeiss Meditec Inc.,Dublin,California,USA),lOLMaster(Carl Zeiss Meditec,Jena,Germany),and Lenstar LS 900/Biograph(Haag-Streit AG,Koeniz,Switzerland/Alcon Laboratories Inc.,Ft Worth,Texas,USA). 展开更多
关键词 anterior camber depth measurement white to white measurement device interchangeability anterior chamber eye
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Techniques for in-situ stress measurement at great depth 被引量:2
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作者 MeifengCai 《Journal of University of Science and Technology Beijing》 CSCD 2004年第6期486-488,共3页
Reliable information of in--situ stress state is necessary for the design andconstruction of most important rock projects. As most rock projects are getting deeper and deeper,traditional techniques of in--situ stress ... Reliable information of in--situ stress state is necessary for the design andconstruction of most important rock projects. As most rock projects are getting deeper and deeper,traditional techniques of in--situ stress measurement are not very suitable. The current techniquesof in--situ stress measurement and their insufficiency for use at great depth are analyzed. Somebasic ideas of the development of new techniques and the improvement of current techniques for useat great depth are provided. 展开更多
关键词 TECHNIQUES in-situ stress measurement at great depth
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A real-time measuring technology for studying distortion of hydraulic turbine blade castings during heat treatment process 被引量:1
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作者 Yu Hailiang Kang Jinwu +3 位作者 Nie Gang Long Haimin Hao Xiaokun Huang Tianyou 《China Foundry》 SCIE CAS 2011年第3期300-304,共5页
During heat treatment process, the distortion behavior inevitably appears in hydraulic turbine blade castings. In this research, a technology was developed for real-time measurement of the distortion in hydraulic turb... During heat treatment process, the distortion behavior inevitably appears in hydraulic turbine blade castings. In this research, a technology was developed for real-time measurement of the distortion in hydraulic turbine blade castings at the still air cooling and forced air cooling stages during heat treatment process. The method was used to measure the distortion behavior at the cooling stages in both normalizing and tempering processes. At the normalization, the distortion at the blade comer near outlet side undergoes four stages with alternating bending along positive and negative directions. At the tempering stage, the distortion could be divided into two steps. The temperature difference between the two surfaces of blade casting was employed to analyze the distortion mechanism. The measured results could be applied to guide the production, and the machining allowance could be reduced by controlling the distortion behavior. 展开更多
关键词 real-time measuring DISTORTION hydraulic turbine blade casting heat treatment
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基于Shuffle-ZoeDepth单目深度估计的苗期玉米株高测量方法
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作者 赵永杰 蒲六如 +2 位作者 宋磊 刘佳辉 宋怀波 《农业机械学报》 EI CAS CSCD 北大核心 2024年第5期235-243,253,共10页
株高是鉴别玉米种质性状及作物活力的重要表型指标,苗期玉米遗传特性表现明显,准确测量苗期玉米植株高度对玉米遗传特性鉴别与田间管理具有重要意义。针对传统植株高度获取方法依赖人工测量,费时费力且存在主观误差的问题,提出了一种融... 株高是鉴别玉米种质性状及作物活力的重要表型指标,苗期玉米遗传特性表现明显,准确测量苗期玉米植株高度对玉米遗传特性鉴别与田间管理具有重要意义。针对传统植株高度获取方法依赖人工测量,费时费力且存在主观误差的问题,提出了一种融合混合注意力信息的改进ZoeDepth单目深度估计模型。改进后的模型将Shuffle Attention模块加入Decoder模块的4个阶段,使Decoder模块在对低分辨率特征图信息提取过程中能更关注特征图中的有效信息,提升了模型关键信息的提取能力,可生成更精确的深度图。为验证本研究方法的有效性,在NYU-V2深度数据集上进行了验证。结果表明,改进的Shuffle-ZoeDepth模型在NYU-V2深度数据集上绝对相对差、均方根误差、对数均方根误差为0.083、0.301 mm、0.036,不同阈值下准确率分别为93.9%、99.1%、99.8%,均优于ZoeDepth模型。同时,利用Shuffle-ZoeDepth单目深度估计模型结合玉米植株高度测量模型实现了苗期玉米植株高度的测量,采集不同距离下苗期玉米图像进行植株高度测量试验。当玉米高度在15~25 cm、25~35 cm、35~45 cm 3个区间时,平均测量绝对误差分别为1.41、2.21、2.08 cm,平均测量百分比误差分别为8.41%、7.54%、4.98%。试验结果表明该方法可仅使用单个RGB相机完成复杂室外环境下苗期玉米植株高度的精确测量。 展开更多
关键词 苗期玉米 株高 单目深度估计 测量方法 混合注意力机制
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High performance hardware architecture for depth measurement by using binocular-camera
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作者 高金良 王鹏 张志杰 《Journal of Measurement Science and Instrumentation》 CAS 2012年第3期211-214,共4页
High performance hardware architecture for depth measurement by using binocular-camera is proposed.In the system,at first,video streams of the target are captured by left and right charge-coupled device(CCD)cameras to... High performance hardware architecture for depth measurement by using binocular-camera is proposed.In the system,at first,video streams of the target are captured by left and right charge-coupled device(CCD)cameras to obtain an image including the target.Then,two different images with two different view points are obtained,and they are used in calculating the position deviation of the image's pixels based on triangular measurement.Finally,the three-dimensional coordinate of the object is reconstructed.All the video data is processed by using field-programmable gate array(FPGA)in real-time.Hardware implementation speeds up the performance and reduces the power,thus,this hardware architecture can be applied in the portable environment. 展开更多
关键词 field-programmable gate array(FPGA) binocular-camera Laplacian of Gaussian filtering depth measurement
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Study on <i>in Vitro</i>Accurate Measurement Method of PICC Insertion Depth
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作者 Na Wang Muhong Deng 《Open Journal of Nursing》 2020年第11期1155-1161,共7页
Objective to study an in vitro accurate measurement method for the placement depth of PICC. Methods 270 patients undergoing PICC catheterization under ultrasound guidance in outpatient PICC catheterization from March ... Objective to study an in vitro accurate measurement method for the placement depth of PICC. Methods 270 patients undergoing PICC catheterization under ultrasound guidance in outpatient PICC catheterization from March to September 2019 were selected by convenient sampling. By using the random number table method, the subjects were divided into group A (horizontal L-type measurement method) and Group B (characteristic index measurement calculation) by 1:1, with 135 cases in each group. X-ray chest radiograph was taken after catheterization in both groups, and the indwelling position of the catheter was adjusted according to the X-ray chest radiograph. The correlation between PICC predicted length and ideal depth and patient satisfaction were compared between the two groups. Results The success rate of PICC catheter tip insertion in group B was 97.78%, while that in control group A was 82.22%, the difference was statistically significant (P < 0.05). The satisfaction degree of patients in group B was significantly higher than that in group A. The differences were statistically significant (P < 0.05). Conclusion Improving the success rate of the precise depth of PICC catheter placement can significantly reduce the incidence of complications, waste of human and material resources caused by adjusting the catheter position, and significantly improve patient satisfaction. 展开更多
关键词 PICC PLACEMENT depth Characteristic Index measurement and Calculation Method
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3D Depth Measurement for Holoscopic 3D Imaging System
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作者 Eman Alazawi Mohammad Rafiq Swash Maysam Abbod 《Journal of Computer and Communications》 2016年第6期49-67,共19页
Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Fea... Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Feature-Edge (AFE) descriptor algorithm is required that provides an individual feature detector for integration of 3D information to locate objects in the scene. The AFE descriptor plays a key role in simplifying the detection of both edge-based and region-based objects. The detector is based on a Multi-Quantize Adaptive Local Histogram Analysis (MQALHA) algorithm. This is distinctive for each Feature-Edge (FE) block i.e. the large contrast changes (gradients) in FE are easier to localise. The novelty of this work lies in generating a free-noise 3D-Map (3DM) according to a correlation analysis of region contours. This automatically combines the exploitation of the available depth estimation technique with edge-based feature shape recognition technique. The application area consists of two varied domains, which prove the efficiency and robustness of the approach: a) extracting a set of setting feature-edges, for both tracking and mapping process for 3D depthmap estimation, and b) separation and recognition of focus objects in the scene. Experimental results show that the proposed 3DM technique is performed efficiently compared to the state-of-the-art algorithms. 展开更多
关键词 Holoscopic 3D Image Edge Detection Auto-Thresholding depthmap Integral Image Local Histogram Analysis Object Recognition and depth measurement
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Case Depth Measurement of Induction Hardening Using Image Processing
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作者 Kitti Pongsathaporn Pramuk Jenkittiyon +1 位作者 Siriporn Daopiset Somnuk Watanasriyakul 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期564-566,共3页
Case depth measurement of the induction hardened steel parts is necessary for quality control. Vickers microhardness test is the most industrially accepted method to identify the case depth. But this method is a time ... Case depth measurement of the induction hardened steel parts is necessary for quality control. Vickers microhardness test is the most industrially accepted method to identify the case depth. But this method is a time consuming one and it requires expensive equipment. The aim of this study is to develop a different method to determine the case depth using image processing. The surface hardened steel samples were cross cut, ground and etched with Nital. The etched macrosectioned specimens were scanned by a scanner. The scanned images were evaluated by the developed software. The principle of the software is to identify the gray level difference. The effective case depths of the surface hardened specimens obtained by Vickers microhardness test and the developed method were compared. It was found that the deviation of the developed method was ±0.12 mm at the case depth range of 0.6 - 2.0 mm and mm at the case depth range of 2.1 - 4.3 mm. The measuring time was only 20% of Vickers microhardness test. The deviation range is much lower than the tolerance case depth specification for induction hardening in general. 展开更多
关键词 图像处理 表面硬化深度 感应淬火 质量控制
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A Trusted Measurement Scheme Suitable for the Clients in the Trusted Network 被引量:3
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作者 GONG Bei ZHANG Jianbiao +1 位作者 YE Xiaolie SHEN Changxiang 《China Communications》 SCIE CSCD 2014年第4期143-153,共11页
The trusted network connection is a hot spot in trusted computing field and the trust measurement and access control technology are used to deal with network security threats in trusted network.But the trusted network... The trusted network connection is a hot spot in trusted computing field and the trust measurement and access control technology are used to deal with network security threats in trusted network.But the trusted network connection lacks fine-grained states and real-time measurement support for the client and the authentication mechanism is difficult to apply in the trusted network connection,it is easy to cause the loss of identity privacy.In order to solve the abovedescribed problems,this paper presents a trust measurement scheme suitable for clients in the trusted network,the scheme integrates the following attributes such as authentication mechanism,state measurement,and real-time state measurement and so on,and based on the authentication mechanism and the initial state measurement,the scheme uses the realtime state measurement as the core method to complete the trust measurement for the client.This scheme presented in this paper supports both static and dynamic measurements.Overall,the characteristics of this scheme such as fine granularity,dynamic,real-time state measurement make it possible to make more fine-grained security policy and therefore it overcomes inadequacies existing in the current trusted network connection. 展开更多
关键词 trusted computing trusted network AUTHENTICATION state measurement real-time measurement
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Measurement and Analysis of PDDs Profile and Output Factors for Small Field Sizes by cc13 and Micro-Chamber cc01 被引量:1
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作者 Muhammad Kamran Rasheed Nasir Nauman Amjad +1 位作者 Aasia Razzaq Tariq Siddique 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第1期36-56,共21页
Small radiation fields are abundantly used in modern radiotherapy techniques like in IMRT and SRS. In order to commission these techniques, dosimetric data for small fields is required. The purpose of this study is to... Small radiation fields are abundantly used in modern radiotherapy techniques like in IMRT and SRS. In order to commission these techniques, dosimetric data for small fields is required. The purpose of this study is to compare dosimetric measurements with two different ion chambers cc13, and cc01 for smaller fields. Dosimetric measurements are beam profile, output factor, pdds, and collimator factor. Dosimetric data is acquired in water phantom for two different photon beam energies 6 MV and 15 MV with zero gantry angle. In beam profiles cc13 chamber, measure wider penumbra as compare to cc01. And this wider measurement of penumbra occurs for smaller as well as for larger field sizes. Accumulated relative error in the measurement of penumbra for number of field sizes and 6 MV at dmax, and at 10 cm depth are 34.32% and 27.72% respectively. Accumulated relative error in the measurement of penumbra for number of field sizes and 15 MV at dmax, and at 10 cm depth are 28.49% and 23.92%. In case of output factor for smaller fields cc13 underestimates the output factor relative to cc01, with non-linear increase for smaller fields. But for larger fields, this increase in output factor is almost linear difference of two chambers is decreased. For very smaller fields × 2 cm, relative error in output factor of cc13 and cc01 is greater than 5% and rapidly increases with decreasing field size. But for lager fields, this relative error is negligible. In measurement of pdds after the buildup region difference occurs in the response of two chambers cc13 and cc01 for smaller fields. For field sizes ≤2 cm × 2 cm average cc13-cc01 at various depths 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, and 80 cm is almost greater than 0.5 cm. And similarly as output factor, this difference (cc13-cc01) increases with field size decreasing. 展开更多
关键词 PERCENTAGE depth Dose PDD Intensity Modulation Radiotherapy IMRT STEREOTACTIC Radio Surgery SRS measurement of Output Factor SCP
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Designing similarity measurement with distance measure and application on laterally directional mode flight test 被引量:1
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作者 PARK Wook-je LEE Sang-min LEE Sang-hyuk 《Journal of Central South University》 SCIE EI CAS 2012年第4期1032-1039,共8页
Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obt... Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obtained through analyzing the certainty and uncertainty of fuzzy membership functions,which were designed based on well-known Hamming distance.It was applied to the fault detection of primary control surface stuck of uninhabited aerial vehicle(UAV).At post-failure control surface,if the UAV is controllable and trimmable using other control surfaces,the UAV is able to fly or return to the safety region through reconfiguration of flight control system.To detect the fault,similarity measure computations were carried out.This result could be applicable with the real-time parameter estimation method.By monitoring the value of coefficients due to the control surface deviation,it becomes aware that the control surface fault occurs or not.The control surface stuck position and value were separated by comparing the trim value with the reference value.This is the advantage of increasing in reliability without adding sensors or with additional low cost. 展开更多
关键词 similarity measure fault detection and isolation real-time parameter estimation control surface stuck
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Cold Atom Cloud with High Optical Depth Measured with Large Duty Cycle
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作者 张骏 顾振杰 +2 位作者 钱鹏 韩枝光 陈洁菲 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期96-99,共4页
We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluat... We present a cold atom system with a dark-line two-dimensional magneto-optical trap, to increase the atomic density by suppressing the atomic radiation pressure. Optical depth (OD) and duty cycle are used to evaluate the system performance. We demonstrate a 100% increase in OD with the dark line, and obtain an ultrahigh OD of 264 with 10% for the duty cycle. Also, with an efficient dark line region, the OD could maintain above i00 with duty cycle as high as 30%. The cold atomic ensemble with an ultrahigh OD with a 10%-30% duty cycle is particularly advantageous in quantum i^formation processing and communication. 展开更多
关键词 Cold Atom Cloud with High Optical depth measured with Large Duty Cycle MOT OD
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Establishment of a Real-time Fluorescent Quantitative PCR Assay for Detection of Genetically Modified Maize Line MON88017
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作者 Jun SONG Dong WANG 《Agricultural Biotechnology》 CAS 2017年第1期15-19,22,共6页
In order to improve the standardized technical systems of quantitative analyses for genetically modified organisms (GMOs) and products, ensure bio-safety and reduce ecological risk in China, a real-time fluorescent ... In order to improve the standardized technical systems of quantitative analyses for genetically modified organisms (GMOs) and products, ensure bio-safety and reduce ecological risk in China, a real-time fluorescent quantitative PCR assay was established for detection of genetically modified maize line MON88017. The established method was evaluated based on the specificity, sensitivity, accuracy and measurement uncertainty. The results showed that the established method had strong specificity in detection of genetically modified maize line MON88017. 1.50% MON88017 sample was detected with 29 replica- tions. The average measured value ( 1. 541% ) was close to the actual value ( 1.50% ) and the relative deviation was 2.70%. The variation coefficient of the measured value was 0.110 g ; the recovery was 100.00% and the measurement uncertainty was 0. 096. The limit of detection for genetically modified maize line MON88017 with the established method was 5 copies at the 97.5% confidence level. Thus, the real-time fluorescent quantitative PCR assay established in this study exhibited high specificity, accuracy and sensitivity, which could provide technical support for the safety supervision of genetically modified organ- isms and products in China. 展开更多
关键词 Genetically modified maize real-time fluorescent quantitative PCR SPECIFICITY Sensitivity ACCURACY measurement uncertainty
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