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Development of a toroidal soft x-ray imaging system and application for investigating three-dimensional plasma on J-TEXT
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作者 赵传旭 李建超 +9 位作者 张晓卿 王能超 丁永华 杨州军 江中和 严伟 李杨波 毛飞越 任正康 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期94-99,共6页
A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and locat... A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and located on the vacuum chamber wall at toroidal positionsφof 126.4°and 272.6°,respectively,while one set was established previously atφ=65.50.Each set of SXR arrays consists of three arrays viewing the plasma poloidally,and hence can be used separately to obtain SXR images via the tomographic method.The sawtooth precursor oscillations are measured by T-SXRI,and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions,hence providing measurement of the 3D structure of precursor oscillations.The observed 3D structure is consistent with the helical structure of the m/n=1/1 mode.The experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma. 展开更多
关键词 SXR imaging J-TEXT tokamak three-dimensional measurement MHD
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Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits
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作者 Zuchao Liang Dong Wang +4 位作者 Guanghe Li Guangyu Sun Mingyu Yu Dong Xia Chunjian Ding 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期507-520,共14页
The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of signi... The 2D limit equilibrium method is widely used for slope stability analysis.However,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical effects.Consequently,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope engineering.Using the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding mass.By integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is proposed.Subsequently,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is examined.The analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear failure.The spatial form equation of the sliding mass comprises an ellipsoid and weak plane equation.The analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite slopes.Furthermore,the3D stability coefficient of the composite slope exhibits an exponential correlation with the coordinated development distance,with the coefficient gradually decreasing as the coordinated development distance increases.These findings provide a theoretical guideline for designing similar slope shape parameters and conducting stability analysis. 展开更多
关键词 Composite slope Destabilization mechanism 3D mechanical effect Three-dimensional stability Coordinated development distance
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Volumetric measurement techniques for assessment of cutaneous neurofibromas:A review
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作者 Xinyu Wang Jiayi Xu +2 位作者 Yun Zhu Chengjiang Wei Zhichao Wang 《Chinese Journal of Plastic and Reconstructive Surgery》 2024年第2期83-86,共4页
Cutaneous neurofibroma(cNF)is a prevalent clinical manifestation of neurofibromatosis type 1,significantly affecting the well-being and quality of life of the affected individuals.The adoption of reliable and reproduc... Cutaneous neurofibroma(cNF)is a prevalent clinical manifestation of neurofibromatosis type 1,significantly affecting the well-being and quality of life of the affected individuals.The adoption of reliable and reproducible volumetric measurement techniques is essential for precisely evaluating tumor burden and plays a critical role in the development of effective treatments for cNF.This study focuses on widely used volumetric measurement techniques,including vernier calipers,ultrasound,computed tomography,magnetic resonance imaging,and three-dimensional scanning imaging.It outlines the merits and drawbacks of each technique in assessing the cNF load,providing an overview of their current applications and ongoing research advancements in this domain. 展开更多
关键词 Cutaneous neurofibroma Tumor volume measurement Vernier caliper Ultrasound Computed tomography Magnetic resonance imaging Three-dimensional scanning imaging
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Novel Distance Measures on Hesitant Fuzzy Sets Based on Equal-Probability Transformation and Their Application in Decision Making on Intersection Traffic Control
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作者 Fangwei Zhang Yi Zhao +2 位作者 Jun Ye Shuhong Wang Jingyi Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1589-1602,共14页
The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special... The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special way.Firstly,a probability density function is assigned for any given HFE.Thereafter,equal-probability transformation is introduced to transform HFEs with different cardinal numbers on the condition into the same probability density function.The characteristic of this transformation is that the higher the consistency of the membership degrees in HFEs,the higher the credibility of the mentioned membership degrees is,then,the bigger the probability density values for them are.According to this transformation technique,a set of novel distance measures on HFSs is provided.Finally,an illustrative example of intersection traffic control is introduced to show the usefulness of the given distance measures.The example also shows that this study is a good complement to operation theories on HFSs. 展开更多
关键词 Hesitant fuzzy sets equal-probability mapping distance measure intersection traffic control cardinality theory
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Review of low timing jitter mode-locked fiber lasers and applications in dual-comb absolute distance measurement 被引量:9
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作者 Haosen Shi Youjian Song +6 位作者 Runmin Li Yuepeng Li Hui Cao Haochen Tian Bowen Liu Lu Chai Minglie Hu 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2018年第4期205-217,共13页
Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperatur... Passively mode-locked fiber lasers emit femtosecond pulse trains with excellent short-term stability. The quantum-limited timing jitter of a free running femtosecond erbium-doped fiber laser working at room temperature is considerably below one femtosecond at high Fourier frequency. The ultrashort pulse train with ultralow timing jitter enables absolute time-of-flight measurements based on a dual-comb implementation, which is typically composed of a pair of optical frequency combs generated by femtosecond lasers. Dead-zone-free absolute distance measurement with sub-micrometer precision and kHz update rate has been routinely achieved with a dual-comb configuration, which is promising for a number of precision manufacturing applications, from large step-structure measurements prevalent in microelectronic profilometry to three coordinate measurements in large-scale aerospace manufacturing and shipbuilding. In this paper, we first review the sub-femtosecond precision timing jitter characterization methods and approaches for ultralow timing jitter mode-locked fiber laser design. Then, we provide an overview of the state-of-the-art dual-comb absolute ranging technology in terms of working principles, experimental implementations, and measurement precisions. Finally, we discuss the impact of quantum-limited timing jitter on the dual-comb ranging precision at a high update rate. The route to highprecision dual-comb range finder design based on ultralow jitter femtosecond fiber lasers is proposed. 展开更多
关键词 TIMING JITTER MODE-LOCKED lasers Dual-comb ABSOLUTE distance measurement
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Distance Measurement Model Based on RSSI in WSN 被引量:25
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作者 Jiuqiang Xu Wei Liu +2 位作者 Fenggao Lang Yuanyuan Zhang Chenglong Wang 《Wireless Sensor Network》 2010年第8期606-611,共6页
The relationship between RSSI (Received Signal Strength Indication) values and distance is the foundation and the key of ranging and positioning technologies in wireless sensor networks. Log-normal shadowing model (LN... The relationship between RSSI (Received Signal Strength Indication) values and distance is the foundation and the key of ranging and positioning technologies in wireless sensor networks. Log-normal shadowing model (LNSM), as a more general signal propagation model, can better describe the relationship between the RSSI value and distance, but the parameter of variance in LNSM is depended on experiences without self-adaptability. In this paper, it is found that the variance of RSSI value changes along with distance regu- larly by analyzing a large number of experimental data. Based on the result of analysis, we proposed the relationship function of the variance of RSSI and distance, and established the log-normal shadowing model with dynamic variance (LNSM-DV). At the same time, the method of least squares(LS) was selected to es- timate the coefficients in that model, thus LNSM-DV might be adjusted dynamically according to the change of environment and be self-adaptable. The experimental results show that LNSM-DV can further reduce er- ror, and have strong self-adaptability to various environments compared with the LNSM. 展开更多
关键词 WSN DYNAMIC Variance DISTANCE MEASUREMENT RSSI Log-Normal SHADOWING Model
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Multi-objective strategy to optimize dithering technique for high-quality three-dimensional shape measurement 被引量:2
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作者 Ning Cai Zhe-Bo Chen +1 位作者 Xiang-Qun Cao Bin Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期381-386,共6页
Dithering optimization techniques can be divided into the phase-optimized technique and the intensity-optimized technique. The problem with the former is the poor sensitivity to various defocusing amounts, and the pro... Dithering optimization techniques can be divided into the phase-optimized technique and the intensity-optimized technique. The problem with the former is the poor sensitivity to various defocusing amounts, and the problem with the latter is that it cannot enhance phase quality directly nor efficiently. In this paper, we present a multi-objective optimization framework for three-dimensional(3D) measurement by utilizing binary defocusing technique. Moreover, a binary patch optimization technique is used to solve the time-consuming issue of genetic algorithm. It is demonstrated that the presented technique consistently obtains significant phase performance improvement under various defocusing amounts. 展开更多
关键词 three-dimensional(3D) SHAPE measurement MULTI-OBJECTIVE dithering GENETIC algorithm
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A novel algorithm for distance measurement using stereo camera 被引量:2
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作者 Elmehdi Adil Mohammed Mikou Ahmed Mouhsen 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第2期177-186,共10页
Distance estimation can be achieved by using active sensors or with the help of passive sensors such as cameras.The stereo vision system is generally composed of two cameras to mimic the human binocular vision.In this... Distance estimation can be achieved by using active sensors or with the help of passive sensors such as cameras.The stereo vision system is generally composed of two cameras to mimic the human binocular vision.In this paper,a Python-based algorithm is pro-posed to find the parameters of each camera,rectify the images,create the disparity maps and finally use these maps for distance measurements.Experiments using real-time im-ages,which were captured from our stereo vision system,of different obstacles posi-tioned at multiple distances(60-200 cm)prove the effectiveness of the proposed program and show that the calculated distance to the obstacle is relatively accurate.The accuracy of distance measurement is up to 99.83%.The processing time needed to calculate the distance between the obstacle and the cameras is less than 0.355 s. 展开更多
关键词 computer vision disparity maps distance measurement PYTHON stereoscopic processing
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Evaluating the contribution of satellite measurements to the reconstruction of three-dimensional ocean temperature fields in combination with Argo profiles 被引量:1
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作者 Jian Chen Hengqian Yan +3 位作者 Senliang Bao Xindong Cui Chengzu Bai Huizan Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第2期65-79,共15页
Assimilation systems absorb both satellite measurements and Argo observations.This assimilation is essential to diagnose and evaluate the contribution from each type of data to the reconstructed analysis,allowing for ... Assimilation systems absorb both satellite measurements and Argo observations.This assimilation is essential to diagnose and evaluate the contribution from each type of data to the reconstructed analysis,allowing for better configuration of assimilation parameters.To achieve this,two comparative reconstruction schemes were designed under the optimal interpolation framework.Using a static scheme,an in situ-only field of ocean temperature was derived by correcting climatology with only Argo profiles.Through a dynamic scheme,a synthetic field was first derived from only satellite sea surface height and sea surface temperature measurements through vertical projection,and then a combined field was reconstructed by correcting the synthetic field with in situ profiles.For both schemes,a diagnostic iterative method was performed to optimize the background and observation error covariance statics.The root mean square difference(RMSD)of the in situ-only field,synthetic field and combined field were analyzed toward assimilated observations and independent observations,respectively.The rationale behind the distribution of RMSD was discussed using the following diagnostics:(1)The synthetic field has a smaller RMSD within the global mixed layer and extratropical deep waters,as in the Northwest Pacific Ocean;this is controlled by the explained variance of the vertical surface-underwater regression that reflects the ocean upper mixing and interior baroclinicity.(2)The in situ-only field has a smaller RMSD in the tropical upper layer and at midlatitudes;this is determined by the actual noise-to-signal ratio of ocean temperature.(3)The satellite observations make a more significant contribution to the analysis toward independent observations in the extratropics;this is determined by both the geographical feature of the synthetic field RMSD(smaller at depth in the extratropics)and that of the covariance correlation scales(smaller in the extratropics). 展开更多
关键词 satellite measurements ARGO three-dimensional reconstruction ocean temperature
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Three-Dimensional Measurement and Reconstruction of Fabric Drape Shape 被引量:1
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作者 沈毅 尹红媛 刘玄木 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期39-42,共4页
This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes... This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics. 展开更多
关键词 fabric drape non-contact measurement structurelight image process three-dimension reconstruction.
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Information fusion of train speed and distance measurements based on fuzzy adaptive Kalman filter algorithm 被引量:1
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作者 FAN Ze yuan DONG Yu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第3期286-292,共7页
The measurement accuracy of speed and distance in high speed train directly affects the control precision and driving efficiency of train control system. To improve the capability of train self control, a combined spe... The measurement accuracy of speed and distance in high speed train directly affects the control precision and driving efficiency of train control system. To improve the capability of train self control, a combined speed measurement and positioning method based on speed sensor and radar which is assisted by global positioning system(GPS) is proposed to improve the accuracy of measurement and reduce the dependence on the ground equipment. In consideration of the fact that the filtering precision of Kalman filter will decrease when the statistical characteristics are changing, this paper uses fuzzy comprehensive evaluation method to evaluate the sub filter, and information distribution coefficients are dynamically adjusted according to filtering reliability, which can improve the fusion accuracy and fault tolerance of the system. The sub filter is required to carry on the covariance shaping adaptive filtering when it is in the suboptimal state. The adjustment factor of error covariance is obtained according to the minimized cost function, which can improve the matching degree between the measured residual variance and the system recursive residual. The simulation results show that the improved filter algorithm can track the changes of the system effectively, enhance the filtering accuracy significantly, and improve the measurement accuracies of train speed and distance. 展开更多
关键词 information fusion federated Kalman filter fuzzy comprehensive evaluation train speed and distance measurements
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Feature Selection Based on Distance Measurement 被引量:1
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作者 Mingming Yang Junchuan Yang 《Journal of New Media》 2021年第1期19-27,共9页
Every day we receive a large amount of information through different social media and software,and this data and information can be realized with the advent of data mining methods.In the process of data mining,to solv... Every day we receive a large amount of information through different social media and software,and this data and information can be realized with the advent of data mining methods.In the process of data mining,to solve some high-dimensional problems,feature selection is carried out in limited training samples,and effective features are selected.This paper focuses on two Relief feature selection algorithms:Relief and ReliefF algorithm.The differences between them and their respective applicable scopes are analyzed.Based on Relief algorithm,the high weight feature subset is obtained,and the correlation between features is calculated according to the mutual information distance measure,and the high redundant features are removed to obtain the feature subset with higher quality.Experimental results on six datasets show the effectiveness of our method. 展开更多
关键词 Feature selection mutual information distance measurement RELIEF
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Optimization of measurement distance of (109)~Cd K XRF system for obese subjects 被引量:1
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作者 HUANG Shi-Bin +3 位作者 McNEILL F E 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第1期86-88,共3页
The precision of results obtained from the ^109Cd K XRF in vivo measurement system of bone lead for obses subjects with high BMI( body mass index)was poor.The main factor affecting the precision was the distance betwe... The precision of results obtained from the ^109Cd K XRF in vivo measurement system of bone lead for obses subjects with high BMI( body mass index)was poor.The main factor affecting the precision was the distance between tibia and detector.Compared with the standard phantom,a large phantom was used to simulate the obese subject in the measurements at different distances to the detector.The counts of Compton scattering increased highly because of the tissue overlying and surrounding tibia of the obese subject.When the distance between leg and detector was too small,the instrument would produce the distorted X-ray spectra,so that the obtained data were inaccurate,In order to ensure good measuremtn precision and accuracy,the distance between leg and detector should be maintained at 25mm during the counting period.Meanwhile,the dead time displayed instantly on the instrument should be controlled to around 30%. 展开更多
关键词 X射线 荧光光谱 XRF 镉109 优化 人体 镉积累 测量
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A method for phase reconstruction in optical three-dimensional shape measurement
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作者 乔闹生 贺志 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期267-270,共4页
In optical three-dimensional shape measurement, a method of improving the measurement precision for phase reconstruction without phase unwrapping is analyzed in detail. Intensities of any five consecutive pixels that ... In optical three-dimensional shape measurement, a method of improving the measurement precision for phase reconstruction without phase unwrapping is analyzed in detail. Intensities of any five consecutive pixels that lie in the x-axis direction of the phase domain are given. Partial derivatives of the phase function in the x- and y-axis directions are obtained with a phase-shifting mechanism, the origin of which is analysed. Furthermore, to avoid phase unwrapping in the phase reconstruction, we derive the gradient of the phase function and perform a two-dimensional integral along the x- and y-axis directions. The reconstructed phase can be obtained directly by performing numerical integration, and thus it is of great convenience for phase reconstruction. Finally, the results of numerical simulations and practical experiments verify the correctness of the proposed method. 展开更多
关键词 phase reconstruction optical three-dimensional shape measurement measurement pre-cision
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A fast and precise three-dimensional measurement system based on multiple parallel line lasers
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作者 Yao Wang Bin Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第2期276-284,共9页
This paper conducts a trade-off between efficiency and accuracy of three-dimensional(3 D)shape measurement based on the triangulation principle,and introduces a flying and precise 3 D shape measurement method based on... This paper conducts a trade-off between efficiency and accuracy of three-dimensional(3 D)shape measurement based on the triangulation principle,and introduces a flying and precise 3 D shape measurement method based on multiple parallel line lasers.Firstly,we establish the measurement model of the multiple parallel line lasers system,and introduce the concept that multiple base planes can help to deduce the unified formula of the measurement system and are used in simplifying the process of the calibration.Then,the constraint of the line spatial frequency,which maximizes the measurement efficiency while ensuring accuracy,is determined according to the height distribution of the object.Secondly,the simulation analyzing the variation of the systemic resolution quantitatively under the circumstance of a set of specific parameters is performed,which provides a fundamental thesis for option of the four system parameters.Thirdly,for the application of the precision measurement in the industrial field,additional profiles are acquired to improve the lateral resolution by applying a motor to scan the 3 D surface.Finally,compared with the line laser,the experimental study shows that the present method of obtaining 41220 points per frame improves the measurement efficiency.Furthermore,the accuracy and the process of the calibration are advanced in comparison with the existing multiple-line laser and the structured light makes an accuracy better than 0.22 mm at a distance of 956.02 mm. 展开更多
关键词 three-dimensional shape measurement multiple parallel line lasers fast and precise measurement parameter calibration
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On the Probable Cause of the Discrepancies between Hipparcos and VLBI Pleiades Distance Measurements
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作者 Ernst Karl Kunst 《Natural Science》 2014年第17期1293-1295,共3页
It will show, a recent extension of special relativity on the grounds of a novel concept of velocity, which also predicts the speed of transversal motions on the plane of the sky to increase with enduring observation ... It will show, a recent extension of special relativity on the grounds of a novel concept of velocity, which also predicts the speed of transversal motions on the plane of the sky to increase with enduring observation time, to fully explain the differences of the observational results of the former experiments referring to the distance of the Pleiades from Earth. 展开更多
关键词 PLEIADES DISCREPANCIES in Distance Measurements DUALITY of Velocity Dependent on One-Way or Two-Way Measurement TRANSVERSAL Motions on the Plane of the Sky Duration of Observation
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Target Detection Improvement in Distance Measurement System Using Two Rotatable Cameras for FPSO
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作者 Yoshinobu Hagiwara Akio Kita Akimasa Suzuki Yongwoon Choi Kazuhiro Watanabe 《Journal of Mechanics Engineering and Automation》 2013年第5期290-297,共8页
This paper describes target detection improvement in a distance measurement system using two rotatable cameras for floating production, storage and offloading (FPSO) facilities. The authors have developed a distance... This paper describes target detection improvement in a distance measurement system using two rotatable cameras for floating production, storage and offloading (FPSO) facilities. The authors have developed a distance measurement system that consists of two rotatable cameras on a ship and a target on a wharf for the automatic berthing of ships. This system measures a distance by detecting and tracking the target on the wharf using the two rotatable cameras on the ship. Our goal is to apply this distance measurement system to an automatic relative positioning system for a ship at an FPSO facility. In this application, the shape of the target in the images captured by the cameras is deformed by their relative positions and attitudes, which increases the measurement errors. To solve this problem, we propose a target detection method that improves the target deformations. The proposed target detection method is able to detect the deformed targets using a target database that is created by image conversion with the perspective projection of a reference target. By using the proposed target detection method, the distance measurement error is decreased. Experimental results on a miniature scale and in an indoor environment confirmed that the measurement error of the relative distance is decreased by using the proposed target detection method. 展开更多
关键词 Distance measurement stereo camera image matching DATABASE ship.
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Three-Dimensional Velocity Distribution Measurement Using Ultrasonic Velocity Profiler with Developed Transducer
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作者 Naruki Shoji Hiroshige Kikura +1 位作者 Hideharu Takahashi Wongsakorn Wongsaroj 《Journal of Flow Control, Measurement & Visualization》 2022年第1期32-55,共24页
This study describes an ultrasonic velocity profiler that uses a <span style="white-space:normal;"><span style="font-family:;" "="">new ultrasonic array transducer with u... This study describes an ultrasonic velocity profiler that uses a <span style="white-space:normal;"><span style="font-family:;" "="">new ultrasonic array transducer with unique 5-element configuration</span></span><span style="white-space:normal;"><span style="font-family:;" "="">, with all five elements acting as transmitters and four elements as receivers. The receivers are designed to reduce the amount of uncertainty. As the fluid moves through this setup, four Doppler frequencies are obtained. The multi-dimensional velocity information along the measurement line can be reconstructed. The transducer has a compact geometry suitable for a wide range of applications, including narrow flow areas. The transducer’s basic frequency and sound pressure are selected and evaluated to be compatible with the application. First, to confirm the measurement ability, the measurement of the developed system in two-dimensional flow is validated by comparing it to the theoretical data. The uncertainty of measurement was within 15%. Second, the three-dimensional measurement in turbulent and swirling flow is proved experimentally to check the applicability of the proposed technique.</span></span> 展开更多
关键词 Doppler Frequency Liquid Velocity Three-Dimensional Measurement Transducer Design ULTRASONIC
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Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology
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作者 胡永成 《外科研究与新技术》 2011年第2期125-125,共1页
Objective To discuss the measurement of bone tumor volume on the basis of three dimensional images segmentation technology. Methods Twenty patients with lacunar bone tumor from Tianjin Hospital and Tongji Hospital wer... Objective To discuss the measurement of bone tumor volume on the basis of three dimensional images segmentation technology. Methods Twenty patients with lacunar bone tumor from Tianjin Hospital and Tongji Hospital were included in the 展开更多
关键词 BONE Digital measurement of bone tumor volume by CT three-dimensional reconstruction technology CT
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On Similarity Measures and Distance Measures of Fuzzy Soft Sets 被引量:3
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作者 刘雅雅 秦克云 王玲 《Chinese Quarterly Journal of Mathematics》 2015年第3期349-357,共9页
In this paper we introduce several new similarity measures and distance measures between fuzzy soft sets, these measures are examined based on the set-theoretic approach and the matching function. Comparative studies ... In this paper we introduce several new similarity measures and distance measures between fuzzy soft sets, these measures are examined based on the set-theoretic approach and the matching function. Comparative studies of these measures are derived. By introducing two general formulas, we propose a new method to define the similarity measures and the distance measures between two fuzzy soft sets with different parameter sets. 展开更多
关键词 FUZZY SOFT SET SIMILARITY MEASURE DISTANCE MEASURE
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