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Color Measurement of Segmented Printed Fabric Patterns in Lab Color Space from RGB Digital Images 被引量:7
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作者 Charles Kumah Ning Zhang +1 位作者 Rafiu King Raji Ruru Pan 《Journal of Textile Science and Technology》 2019年第1期1-18,共18页
Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the... Colors of textile materials are the first parameter of quality evaluated by consumers and a key component considered in selecting printed fabric. In the textiles industry, digital printed fabric analysis is one of the basic elements in successfully utilizing a color mechanism scheme and objectively evaluating fabric color alterations. Precise color measurement, however, is mostly used in sample analysis and quality inspection which help to produce reproducible or similar product. It is important that for quality inspection, the color of the product should be measured as a necessary requirement of quality control whether the product is to be accepted or not. Presented in this study is an unsupervised segmentation of printed fabrics patterns using mean shift algorithm and color measurements over the segmented regions of printed fabric patterns. The results established a consistent and reliable color measurement of multiple color patterns and appearance with the established range without any interactions. 展开更多
关键词 COLOR measurement LAB COLOR space RGB COLOR space Region of INTEREST (ROI) Quality Control
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OBSTACLE PROBLEMS ON RCD(K,N)METRIC MEASURE SPACES
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作者 林锶坍 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期1925-1944,共20页
In this paper,we solve the obstacle problems on metric measure spaces with generalized Ricci lower bounds.We show the existence and Lipschitz continuity of the solutions,and then we establish some regularities of the ... In this paper,we solve the obstacle problems on metric measure spaces with generalized Ricci lower bounds.We show the existence and Lipschitz continuity of the solutions,and then we establish some regularities of the free boundaries. 展开更多
关键词 obstacle problem metric measure space Riemannian curvature-dimension condition
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REVERSE CARLESON MEASURES ON GENERALIZED FOCK SPACES
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作者 曹广福 何莉 张艺渊 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期655-667,共13页
In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equ... In this paper,we characterize reverse Carleson measures for a class of generalized Fock spaces F^(p)_(φ),with 0<p<∞and withφsatisfying dd^(c)_(φ)■ω0.As an application of these results,we obtain several equivalent characterizations for invertible Toeplitz operators Tψ,induced by positive bounded symbols φ on F^(2)_(φ). 展开更多
关键词 reverse Carleson measures invertible Toeplitz operators generalized Fock spaces
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Fast Measurement of Dielectric Conductivity for Space Application by Surface Potential Decay Method 被引量:1
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作者 全荣辉 周凯 +2 位作者 方美华 池卫英 张振龙 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期104-106,共3页
Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the... Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the first few hours after irradiation and exponentially slowly for the remaining time. The measurement of dark conductivity with this method usually takes the slow part and needs a couple of days. Integrating the Fowler formula into the deep dielectric charging equations, we obtain a new expression for the fast decay part. The experimental data of different materials, dose rates and temperatures are fitted by the new expression. Both the dark conductivity and the radiation-induced conductivity are derived and compared with other methods. The result shows a good estimation of dark conductivity and radiation-induced conductivity in high-resistivity polymers, which enables a fast measurement of dielectric conductivity within about 600 rain after irradiation. 展开更多
关键词 Fast measurement of Dielectric Conductivity for space Application by Surface Potential Decay Method
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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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A DERIVATIVE-HILBERT OPERATOR ACTING FROM LOGARITHMIC BLOCH SPACES TO BERGMAN SPACES
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作者 Shanli YE Yun XU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1916-1930,共15页
Letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entriesμn,k=μn+k,whereμn=⨜[0,1)tndμ(t),induces,formally,the operator■where■is an analytic function in.We characterize the measuresμf... Letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entriesμn,k=μn+k,whereμn=⨜[0,1)tndμ(t),induces,formally,the operator■where■is an analytic function in.We characterize the measuresμfor which■is bounded(resp.,compact)operator from the logarithmic Bloch space■into the Bergman space■,where 0≤α<∞,0<p<∞.We also characterize the measuresμfor which■is bounded(resp.,compact)operator from the logarithmic Bloch space■into the classical Bloch space■. 展开更多
关键词 derivative-Hilbert operator logarithmic Bloch space Carleson measure
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TIME-SPACE CONCEPT FOR PRECISION MEASUREMENT 被引量:4
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作者 LIU Xiaokang PENG Donglin ZHU Ge WANG Xianquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期112-115,共4页
The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in... The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in cycle mode. Displacement measuring by magnification is achieved with period measurement by magnification. To change the condition that traditional precision measurement depends on machining precision greatly, the concept of measuring space with time and theory of time-space coordinate transformation are proposed. Guided by the idea of measuring space with time, differential frequency measurement system and time grating displacement sensor are developed based on the proposed novel methods. And high-precision measurement is achieved without high-precision manufacture, which embeds the remarkable characteristics of low cost but high precision to the devices. Experiment and test results conform the validity of the proposed time-space concept. 展开更多
关键词 Time-space Precision measurement Control flow Differential frequency Time grating
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TOEPLITZ OPERATORS BETWEEN WEIGHTED BERGMAN SPACES OVER THE HALF-PLANE
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作者 Lixia FENG Yan LI +1 位作者 Zhiyu WANG Liankuo ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1707-1720,共14页
In this paper,by characterizing Carleson measures,we investigate a class of bounded Toeplitz operator between weighted Bergman spaces with Békolléweights over the half-plane for all index choices.
关键词 weighted Bergman spaces Békolléweights Carleson measure Toeplitz operators
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The Fundamental Definitions in Radar Measurement Principle and Theory of Space and Time
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作者 Lin JinFirst Academy, Ministry of Aero -Space Industry, P.R China P.O.Box 142-30-409, Beijing 100854,China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第3期11-22,共12页
Fundamental definitions of distance and velocity in radar measurement principle are examined and revised from strict theoretical point of view. Synchronization scheme - for clocks in uniform, translatory relative moti... Fundamental definitions of distance and velocity in radar measurement principle are examined and revised from strict theoretical point of view. Synchronization scheme - for clocks in uniform, translatory relative motion is introduced as theoretical foundation for GPS and GLONASS type navigation and positioning technology. Traditional definitions of two-way radar measurement, based on arithmetic mean vlaue concept, turn out to be special cases of revised definitions for one-way radar measurement, based on geometric mean concept, derived from synchronization of moving clocks in accordance with the principle of relativity. The essential physical meaning of Lorentz transformation is interpreted in terms of radar measured parameters. Invariance or absoluteness of four dimensional interval turns out to be invariance or absoluteness of geometric mean time interval. The Lorentz factor turns out to be ratio of geometric mean and arithmetic mean time intervals in terms of radar measured parameters. Theoretical results are illustrated transparently by numerical examples. A crucial experiment for direct testing of the second postulate of special relativity by means of GPS of GLONASS type technology is proposed in this paper. 展开更多
关键词 Radar measurement Theory of space and time Special relativity GPS GLONASS.
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Three Measurement Methods of Two-photon Absorption Cross-section
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作者 LI De-sheng DAI Qin +1 位作者 MA Yu-guang WANG Xi-jun 《Semiconductor Photonics and Technology》 CAS 2006年第4期276-279,共4页
Through the experimental design and theoretical analysis, three technologies used for characterizing the two-photon absorption(TPA) properties, such as nonlinear transmission experiment and theory, Z-scan technology a... Through the experimental design and theoretical analysis, three technologies used for characterizing the two-photon absorption(TPA) properties, such as nonlinear transmission experiment and theory, Z-scan technology and two-photon induced fluorescence method, are introduced. The properties of the three experiments to be utilizable and realizable under desirable limitation are simply analyzed. The advantages of the measurements for TPA characterization are also analyzed. 展开更多
关键词 TPA TPA cross-section measurement method FLUORESCENCE
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Model-Following Designs Using Direct State Derivative Measurement Feedback in Novel Reciprocal State Space Form
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作者 Yuan-Wei Tseng Rong-Ching Wu 《Journal of Applied Mathematics and Physics》 2019年第2期394-409,共16页
The paper introduces effective and straightforward algorithms of both explicit and implicit model-following designs with state derivative measurement feedback in novel reciprocal state space form (RSS) to handle state... The paper introduces effective and straightforward algorithms of both explicit and implicit model-following designs with state derivative measurement feedback in novel reciprocal state space form (RSS) to handle state derivative related performance output and state related performance output design cases. Applying proposed algorithms, no integrators are required. Consequently, implementation is simple and low-cost. Simulation has also been carried out to verify the proposed algorithms. Since acceleration can only be modeled as state derivative in state space form and micro-accelerometer which is the state derivative sensor is getting more and more attentions in many microelectromechanical and nanoelectromechanical systems (MEMS/NEMS) applications, the proposed algorithms are suitable for MEMS/NEMS systems installed with micro-accelerometers. 展开更多
关键词 Reciprocal STATE space Form STATE DERIVATIVE measurement Feedback EXPLICIT Model-Following DESIGN IMPLICIT Model-Following DESIGN
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Some Fundamental Problems of Geodynamics and Application of Earth Observations by Space-Based Measurements 被引量:2
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作者 Ma Zongjin,Zhang Peizhen,Hong Hanjin,and Gao Xianglin Institute of Geology,SSB,Beijing 100029,China 《Earthquake Research in China》 1997年第1期7-17,共11页
Although great-progress has been made in the earth sciences,some fundamental problems of geodynamics remain unsolved.They are concerned with the whole earth as well as regional tectonics,such as the west Pacific and Q... Although great-progress has been made in the earth sciences,some fundamental problems of geodynamics remain unsolved.They are concerned with the whole earth as well as regional tectonics,such as the west Pacific and Qinghai-Xizhang plateau.The new generation of earth observation by space-based measurement will contribute to solving these problems of geodynamics.In this regard,some specific plans about application of these techniques are suggested in this paper. 展开更多
关键词 GEODYNAMICS WEST PACIFIC Qinghai-Xizhang PLATEAU space-BASED measurement
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Time-and-space resolved measurements of the emission uniformity of carbon fibre cathode in high-current pulsed discharge
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作者 刘列 李立民 +2 位作者 徐启福 程国新 苌磊 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期251-257,共7页
The remaining challenges, confronting high-power microwave (HPM) sources and pulsed power generators, stim- ulate the developments of robust relativistic electron beam sources. This paper presents a carbon fibre cat... The remaining challenges, confronting high-power microwave (HPM) sources and pulsed power generators, stim- ulate the developments of robust relativistic electron beam sources. This paper presents a carbon fibre cathode which is tested in a single pulsed power generator. The distribution and the development of cathode plasma are observed by time-and-space resolved diagnostics, and the uniformity of electron beam density is checked by taking x-ray images. A quasistationary behaviour of cathode plasma expansion is observed. It is found that the uniformity of the extracted electron beam is satisfactory in spite of individual plasma jets on the cathode surface. These results show that carbon fibre cathodes can provide a positive prospect for developing a high-quality electron beam. 展开更多
关键词 cold cathode emission uniformity x rays time-and-space resolved measurement
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Protective Measures for Space Environment of Time-honored Brands——With Xi'an City as a Study Case
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作者 谷秋琳 《Journal of Landscape Research》 2010年第7期15-17,22,共4页
Based on the field survey and analysis of representative traditional time-honored shops in Xi'an City,specific measures for protecting their space environment were put forward,and the sustainable preservation and ... Based on the field survey and analysis of representative traditional time-honored shops in Xi'an City,specific measures for protecting their space environment were put forward,and the sustainable preservation and development pattern of such intangible cultural heritages in the future urban development was established. 展开更多
关键词 Time-honored brands INTANGIBLE CULTURAL heritages space environment Protective measures
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CARLESON MEASURES FOR BESOV-SOBOLEV SPACES WITH APPLICATIONS IN THE UNIT BALL OF C^n 被引量:3
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作者 彭茹 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1219-1230,共12页
This paper is devoted to give the connections between Carleson measures for Besov-Sobolev spaces Bp^σ(B) and p-Carleson measure in the unit ball of C^n. As applications, we characterize the Riemann-Stieltjes operat... This paper is devoted to give the connections between Carleson measures for Besov-Sobolev spaces Bp^σ(B) and p-Carleson measure in the unit ball of C^n. As applications, we characterize the Riemann-Stieltjes operators and multipliers acting on Bp(B) spaces by means of Carleson measures for Bp^σ(B). 展开更多
关键词 Carleson measures Besov-Sobolev spaces Riemann-Stieltjes operators MULTIPLIERS
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CARLESON MEASURES,RIEMANN-STIELTJES OPERATORS AND MULTIPLIERS ON F(p,q,s)SPACES IN THE UNIT BALL OF C^n 被引量:3
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作者 彭茹 吴悠 邓方文 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期635-654,共20页
This paper is devoted to characterizing the Riemann-Stieltjes operators and pointwise multipliers on F(p, q, s) spaces in the unit ball of C^n which contain many classical function spaces, such as the Bloch space, B... This paper is devoted to characterizing the Riemann-Stieltjes operators and pointwise multipliers on F(p, q, s) spaces in the unit ball of C^n which contain many classical function spaces, such as the Bloch space, BMOA and Q8 spaces. The boundedness and compactness of these operators on F(p, q, s) spaces are characterized by means of an embedding theorem, i.e., F(p,q, s) spaces boundedly embedded into the tent-type spaces Tp,s^∞(μ) 展开更多
关键词 Carleson measures F(p q s) spaces tent-type spaces Riemann-Stieltjes operators MULTIPLIERS
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Measuring the space between vagina and rectum as it relates to rectocele 被引量:3
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作者 Jin Liu Li-Dong Zhai +2 位作者 Yun-Sheng Li Wan-Xiang Liu Rui-Hua Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第24期3051-3054,共4页
AIM:To measure the normal space between the posterior wall of the vagina and the anterior wall of the respectively rectum using computed tomography(CT) and reveal its were relationship to rectocele. METHODS:A total of... AIM:To measure the normal space between the posterior wall of the vagina and the anterior wall of the respectively rectum using computed tomography(CT) and reveal its were relationship to rectocele. METHODS:A total of twenty female volunteers without rectocele were examined by CT scan.We performed a middle level continuous horizontal pelvic scan from the upper part to the lower part and collected the measurement data to analyze the results using t-test. RESULTS:Twenty volunteers were enrolled in the study. The space between the posterior wall of the vagina and the anterior wall of the rectum was measured at three levels(upper 1/3,middle,lower 1/3 level of vagina). The results showed that the space from the posterior wall of the vagina to the anterior wall of the rectum at the upper 1/3 level and the middle level was 3.896 ±0.3617 mm and 4.6575±0.3052 mm,respectively. When the two groups of data were compared,we found the space at the upper 1/3 level was shorter than at the middle level(P<0.01).Moreover,at the lower 1/3 level the space measured was 10.058±0.4534 mm.The results revealed that the space at the lower 1/3 level was longer than that at the middle level(P<0.01). CONCLUSION:These measurement data may be helpful in assessing rectocele clinical diagnosis and functional outcomes of rectocele repair. 展开更多
关键词 measurement space RECTOCELE Computed tomography
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CARLESON MEASURES AND THE GENERALIZED CAMPANATO SPACES OF VECTOR-VALUED MARTINGALES 被引量:2
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作者 Lin YU Ruhui WANG Shoujiang ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1779-1788,共10页
In this paper, the so-called(p,Ф)-Carleson measure is introduced and the rela-tionship between vector-valued martingales in the general Campanato spaces Lp,Ф(X) and the (p, Ф)-Carleson measures is investigate... In this paper, the so-called(p,Ф)-Carleson measure is introduced and the rela-tionship between vector-valued martingales in the general Campanato spaces Lp,Ф(X) and the (p, Ф)-Carleson measures is investigated. Specifically, it is proved that for q ∈ [2, ∞), the measure d# :-=││ dfk││^qdP dm is a (q, Ф)-Carleson measure on Ω × N for every f ∈ Lq,Ф(X) if and only if X has an equivalent norm which is q-uniformly convex; while for p C (1, 2], the measure dμ :=││dfk││^pP dm is a (p, Ф)-Carleson measure on Ω ×N implies that f ∈ Lp,Ф(X) if and only if X admits an equivalent norm which is p-uniformly smooth. This result extends an earlier result in the literature from BMO spaces to general Campanato spaces. 展开更多
关键词 Carleson measures BMO martingales generalized Campanato spaces uni-formly convex (smooth) Banach spaces
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BOUNDEDNESS OF FRACTIONAL INTEGRALS IN HARDY SPACES WITH NON-DOUBLING MEASURE—In Memory of Professor Sun Yongsheng 被引量:2
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作者 Wengu Chen Yixin Lai 《Analysis in Theory and Applications》 2006年第2期195-200,共6页
Let μ be a Borel measure on R^d which may be non doubling. The only condition that μ must satisfy is μ(Q) ≤ col(Q)^n for any cube Q belong to R^d with sides parallel to the coordinate axes and for some fixed ... Let μ be a Borel measure on R^d which may be non doubling. The only condition that μ must satisfy is μ(Q) ≤ col(Q)^n for any cube Q belong to R^d with sides parallel to the coordinate axes and for some fixed n with 0 〈 n ≤ d. The purpose of this paper is to obtain a boundedness property of fractional integrals in Hardy spaces H^1(μ). 展开更多
关键词 fractional integral Hardy space non-doubling measure
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Risk measures with comonotonic subadditivity or convexity on product spaces 被引量:1
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作者 WEI Lin-xiao MA Yue HU Yi-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第4期407-417,共11页
In this paper, by an axiomatic approach, we propose the concepts of comonotonic subadditivity and comonotonic convex risk measures for portfolios, which are extensions of the ones introduced by Song and Yan (2006). ... In this paper, by an axiomatic approach, we propose the concepts of comonotonic subadditivity and comonotonic convex risk measures for portfolios, which are extensions of the ones introduced by Song and Yan (2006). Representation results for these new introduced risk measures for portfolios are given in terms of Choquet integrals. Links of these newly introduced risk measures to multi-period comonotonic risk measures are represented. Finally, applications of the newly introduced comonotonic coherent risk measures to capital allocations are provided. 展开更多
关键词 Choquet integral comonotonic subadditivity risk measure comonotonic convex risk measure multi-period risk measure capital allocation product space.
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