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Modeling and Investigation of the Wall Thickness Changes and Process Time in Thermo-Mechanical Tube Spinning Process Using Design of Experiments 被引量:1
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作者 Ahmad reza Fazeli Nahrekhalaji Majid Ghoreishi Ebrahim Sharifi Tashnizi 《Engineering(科研)》 2010年第3期141-148,共8页
Tube spinning technology is one of the effective methods of manufacturing large diameter thin-walled shapes. In this research, effects of major parameters of thermo mechanical tube spinning process such as preform'... Tube spinning technology is one of the effective methods of manufacturing large diameter thin-walled shapes. In this research, effects of major parameters of thermo mechanical tube spinning process such as preform's thickness, percentage of thickness reduction, mandrel rotational speed, feed rate, solution treatment time and aging treatment time on the wall thickness changes and process time in thermo-mechanical tube spinning process for fabrication of 2024 aluminum spun tubes using design of experiments (DOE), are studied. The statistical results are verified through some experiments. Results of experimental evaluation are analyzed by variance analysis and mathematic models are obtained. Finally using these models, input parameters for optimum production are achieved. 展开更多
关键词 TUBE SPINNING process time WALL Thickness CHANGES Analysis of Variance (ANOVA) Regression Interaction Effect
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An Improved Algorithm for Segmentation and Determination of Respiratory Phase Times Based on Temporal Processing of Nasal and Mouth Breathing Sound Signals
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作者 Guillermo Kemper Kevin Guerra-Huamán 《Tsinghua Science and Technology》 2025年第6期2522-2543,共22页
This work proposes a computational algorithm to improve the determination of the timing of the respiratory phases.The algorithm was developed using a database of breathing sound signals acquired through properly posit... This work proposes a computational algorithm to improve the determination of the timing of the respiratory phases.The algorithm was developed using a database of breathing sound signals acquired through properly positioned face masks and electret microphones.Most of the proposed works use the frequency domain and decimation in time to detect the respiratory period and phases,as well as some specific pathology.In this work the processing applied is only in time without applying decimation,thus improving the detection of a greater number of respiratory periods.The segmentation is very important since it allows the isolation of phases of the signal to later detect some pathology or to estimate the volume of inspired and exhaled air.The proposed algorithm involves the extraction of signal envelopes with the use of high selectivity filters without decimation and adaptive normalization processes that aim to achieve an adequate detection.In the validation process,the algorithm detection results were compared with the timing of respiratory periods and phases marked by visual inspection.The results show a maximum error of 4.36%for the respiratory period and 3.23%and 3.09%for the expiration and inspiration times,respectively. 展开更多
关键词 envelope detection breathing period breath sound inspiration time expiration time time domain processing
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AN EXPONENTIAL NON-UNIFORM BERRY-ESSEEN BOUND OF SOME TIME INHOMOGENEOUS DIFFUSION PROCESS
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作者 Qiaojing LIU Yaqian LV Baobin WANG 《Acta Mathematica Scientia》 2025年第5期1879-1890,共12页
this paper,we study the exponential non-uniform Berry-Esseen bound for the maximum likelihood estimator of some time inhomogeneous diffusion process.As applications,the optimal uniform Berry-Esseen bound and optimal C... this paper,we study the exponential non-uniform Berry-Esseen bound for the maximum likelihood estimator of some time inhomogeneous diffusion process.As applications,the optimal uniform Berry-Esseen bound and optimal Cramer-type moderate deviations of the Ornstein-Uhlenbeck process andα-Brownian bridge can be obtained.The main methods are the change of measure method and asymptotic analysis technique. 展开更多
关键词 Berry-Esseen bound time inhomogeneous diffusion process Cramer-type mod-erate deviations Ornstein-Uhlenbeck process
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WaveLiteDehaze-Network:A Low-Parameter Wavelet-Based Method for Real-Time Dehazing
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作者 Ali Murtaza Uswah Khairuddin +3 位作者 Ahmad’Athif Mohd Faudzi Kazuhiko Hamamoto Yang Fang Zaid Omar 《CAAI Transactions on Intelligence Technology》 2025年第4期1033-1048,共16页
Although the image dehazing problem has received considerable attention over recent years,the existing models often prioritise performance at the expense of complexity,making them unsuitable for real-world application... Although the image dehazing problem has received considerable attention over recent years,the existing models often prioritise performance at the expense of complexity,making them unsuitable for real-world applications,which require algorithms to be deployed on resource constrained-devices.To address this challenge,we propose WaveLiteDehaze-Network(WLD-Net),an end-to-end dehazing model that delivers performance comparable to complex models while operating in real time and using significantly fewer parameters.This approach capitalises on the insight that haze predominantly affects low-frequency infor-mation.By exclusively processing the image in the frequency domain using discrete wavelet transform(DWT),we segregate the image into high and low frequencies and process them separately.This allows us to preserve high-frequency details and recover low-frequency components affected by haze,distinguishing our method from existing approaches that use spatial domain processing as the backbone,with DWT serving as an auxiliary component.DWT is applied at multiple levels for better in-formation retention while also accelerating computation by downsampling feature maps.Subsequently,a learning-based fusion mechanism reintegrates the processed frequencies to reconstruct the dehazed image.Experiments show that WLD-Net out-performs other low-parameter models on real-world hazy images and rivals much larger models,achieving the highest PSNR and SSIM scores on the O-Haze dataset.Qualitatively,the proposed method demonstrates its effectiveness in handling a diverse range of haze types,delivering visually pleasing results and robust performance,while also generalising well across different scenarios.With only 0.385 million parameters(more than 100 times smaller than comparable dehazing methods),WLD-Net processes 1024×1024 images in just 0.045 s,highlighting its applicability across various real-world scenarios.The code is available at https://github.com/AliMurtaza29/WLD-Net. 展开更多
关键词 discrete wavelet transform real time image processing single image dehazing
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A dynamic programming algorithm for scheduling problems on earliness award and tardiness penalty with time-dependent processing time 被引量:1
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作者 余英 孙世杰 何龙敏 《Journal of Shanghai University(English Edition)》 CAS 2008年第3期204-209,共6页
In this paper, a single-machine scheduling model with a given common due date is considered. Job processing time is a linear decreasing function of its starting time. The objective function is to minimize the total we... In this paper, a single-machine scheduling model with a given common due date is considered. Job processing time is a linear decreasing function of its starting time. The objective function is to minimize the total weighted earliness award and tardiness penalty. Our aim is to find an optimal schedule so as to minimize the objective function. As the problem is NP-hard, some properties and polynomial time solvable cases of this problem are given. A dynamic programming algorithm for the general case of the problem is provided. 展开更多
关键词 scheduling SINGLE-MACHINE linear decreasing processing time EARLINESS TARDINESS
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New multi-DSP parallel computing architecture for real-time image processing 被引量:4
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作者 Hu Junhong Zhang Tianxu Jiang Haoyang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期883-889,共7页
The flexibility of traditional image processing system is limited because those system are designed for specific applications. In this paper, a new TMS320C64x-based multi-DSP parallel computing architecture is present... The flexibility of traditional image processing system is limited because those system are designed for specific applications. In this paper, a new TMS320C64x-based multi-DSP parallel computing architecture is presented. It has many promising characteristics such as powerful computing capability, broad I/O bandwidth, topology flexibility, and expansibility. The parallel system performance is evaluated by practical experiment. 展开更多
关键词 parallel computing image processing REAL-time computer architecture
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Processing Time Prediction Method Based on SVR in Semiconductor Manufacturing 被引量:1
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作者 朱雪初 乔非 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期98-101,共4页
The prediction problem of the actual value of the dynamic parameters in the simulation model in semiconductor manufacturing was discussed. Considering the fact that the default value of processing time of one certain ... The prediction problem of the actual value of the dynamic parameters in the simulation model in semiconductor manufacturing was discussed. Considering the fact that the default value of processing time of one certain equipment in the simulation model was not the same as its actual value,a general data driven prediction model of the processing time was built based on support vector regression( SVR),with the utilization of manufacturing information in manufacturing execution system( MES). The processing time of one certain equipment was highly related to the status of the equipment itself and the wafers being processed. To uncover the relationship of the processing time with the information of historical products,process flow,technical standard of silicon wafers and manual intervention,data were extracted from MES and used to build a prediction model. This model was employed on an ion implantation equipment as a case, and the effectiveness of the proposed method was shown by comparing with other approaches. 展开更多
关键词 SEMICONDUCTOR MANUFACTURING SUPPORT VECTOR regression(SVR) processING time prediction
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SELF-INTERSECTION LOCAL TIME OF ADDITIVE LEVY PROCESS 被引量:2
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作者 钟玉泉 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期261-268,共8页
This article discusses the problem of existence of jointly continuous self-intersection local time for an additive levy process. Here, 'local time' is understood in the sense of occupation density, and by an a... This article discusses the problem of existence of jointly continuous self-intersection local time for an additive levy process. Here, 'local time' is understood in the sense of occupation density, and by an additive Levy process the authors mean a process X = {X(t),t∈ R+N} which has the decomposition X = Xi X2 … XN, each Xl has the lower index αl, α= min{α1,…, αN}. Let Z = (Xt2 - Xt1, …, Xtr - Xtr-1). They prove that if Nrα > d(r-1), then a jointly continuous local time of Z, i.e. the self-intersection local time of X, can be obtained. 展开更多
关键词 Additive Levy process local time self-intersection local time Levy process isotropic stable process
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LOCAL TIME ANALYSIS OF ADDITIVE LVY PROCESSES WITH DIFFERENT LVY EXPONENTS 被引量:2
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作者 钟玉泉 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1155-1164,共10页
Let X1 XN be independent, classical Levy processes on R^d with Levy exponents ψ1,…, ψN, respectively. The corresponding additive Levy process is defined as the following N-parameter random field on R^d, X(t) △=... Let X1 XN be independent, classical Levy processes on R^d with Levy exponents ψ1,…, ψN, respectively. The corresponding additive Levy process is defined as the following N-parameter random field on R^d, X(t) △= X1(t1) + ... + XN(tN), At∈N. Under mild regularity conditions on the ψi's, we derive estimate for the local and uniform moduli of continuity of local times of X = {X(t); t ∈R^N}. 展开更多
关键词 additive Levy processes local time HSlder laws
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High Accuracy Time of Flight Measurement Using Digital Signal Processing Techniques for Subsea Applications 被引量:2
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作者 Muhammad Ashraf Hamza Qayyum 《Journal of Signal and Information Processing》 2011年第4期330-335,共6页
The techniques widely used in ultrasonic measurements are based on the determination of the time of flight (T.o.F). A short train of waves is transmitted and same transducer is used for reception of the reflected sign... The techniques widely used in ultrasonic measurements are based on the determination of the time of flight (T.o.F). A short train of waves is transmitted and same transducer is used for reception of the reflected signal for the pulse-echo measurement applications. The amplitude of the received waveform is an envelope which starts from zero reaches to a peak and then dies out. The echoes are mostly detected by simple threshold crossing technique, which is also cause of error. In this paper digital signal processing is used to calculate the time delay in reception i.e. T.o.F, for which a maximum similarity between the reference and the delayed echo signals is obtained. To observe the effect of phase uncertainties and frequency shifts (Doppler), this processing is carried out, both directly on the actual wave shape and after extracting the envelopes of the reference and delayed echo signals. Several digital signal processing algorithms are considered and the effects of different factors such as sampling rate, resolution of digitization and S/N ratio are analyzed. Result show accuracy, computing time and cost for different techniques. 展开更多
关键词 SONAR SIGNAL processING time of FLIGHT
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A Flexible DSP-Based Network forReal-Time Image-Processing 被引量:5
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作者 MAOHai-cen ZHANGTian-xu JIANGHao-yang WANGYue-huan 《Wuhan University Journal of Natural Sciences》 CAS 2004年第6期921-926,共6页
This paper proposed a general purpose real-time image processing system based on a flexible DSP-based Network, which is implemented by a high bandwidth communication channel, links. The links is realized using FPGA an... This paper proposed a general purpose real-time image processing system based on a flexible DSP-based Network, which is implemented by a high bandwidth communication channel, links. The links is realized using FPGA and provides a bandwidth of 12. 8 Gbit/s. Using the links, The topologic of multi-DSP system can be changed online to meet the variabilities of the parallel algorithm of image processing. The system can be assembled with utmost tens of boards and maintain the high communication speed. Analysis of the system adaptivity to image processing is testified followed by actual results. Key words real-time image processing - multi-DSP - flexible - scalable - FPGA - links CLC number TP 303 Foundation item: Supported by the National Natural Science Foundation of China (60135020)Biography: MAO Hai-cen(1973-), male, Ph.D. candidate, research direction: artificial intelligence, expert system, pattern recognition and image processing 展开更多
关键词 real-time image processing MULTI-DSP FLEXIBLE SCALABLE FPGA LINKS
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A Class of Single Machine Scheduling Problems with Variable Processing Time
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作者 周荷芳 周贤伟 《Journal of Modern Transportation》 2001年第1期93-100,共8页
In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and... In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and so on. The complexity of the problem is determined. [WT5HZ] 展开更多
关键词 single machine scheduling problem NP-HARD variable processing time complexity theory
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Strong NP-Hardness of Single Machine Scheduling Problems with Variable Processing Time
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作者 周贤伟 杜文 朱健梅 《Journal of Modern Transportation》 1998年第2期78-88,共11页
In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' ... In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' of the job on position i and a “normal' processing time of the job. The criteria considered is to minimize scheduled length of all jobs. A lemma is proposed and proved. In no deadline constrained condition, the problem belongs to polynomial time algorithm. It is proved by using 3 partition that if the problem is deadline constrained, its complexity is strong NP hard. Finally, a conjuncture is proposed that is to be proved. 展开更多
关键词 single machine scheduling problem variable processing time strong NP hardness.
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Intercross real-time control strategy in alternating activated sludge process for short-cut biological nitrogen removal treating domestic wastewater 被引量:4
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作者 AKIO TAKIGAWA 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期957-963,共7页
To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,per... To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,performing short-cut nitrogen removal from real domestic wastewater was operated under different control strategies for more than five months.A fixed-time control(FTC) study showed that bending-points on pH and oxidation-reduction potential(ORP)profiles accurately coincided with the major biologic... 展开更多
关键词 alternating activated sludge process CONTINUOUS-FLOW real-time control NITRIFICATION
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ABSOLUTE CONTINUITY OF THE OCCUPATION TIME PROCESSES WITH RESPECT TO LEBESGUE MEASURE FOR SUPER-BROWNIAN MOTION
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作者 王永进 《Acta Mathematica Scientia》 SCIE CSCD 1994年第S1期1-7,共7页
Some properties of Super-Brownian motion have been approached by Dawson & Hochberg [1], Iscoe [2] & L3], Konno & Shiga [4] and so on. In this paper, we limit our attention to the occupation time processes ... Some properties of Super-Brownian motion have been approached by Dawson & Hochberg [1], Iscoe [2] & L3], Konno & Shiga [4] and so on. In this paper, we limit our attention to the occupation time processes of the Super-Brownian motion,and try to give an intuitive proof for their absolute continuity with respect to the Lebesgue measure on Rd (d≤3) when the initial measure of the Super-Brownian motion has the absolute continuity. 展开更多
关键词 Super-process Occupation time process Absolute continuity.
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A Genetic Algorithm for Single Machine Scheduling with Fuzzy Processing Time and Multiple Objectives
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作者 吴超超 顾幸生 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期185-189,共5页
In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm... In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm which is suitable for solving these problems is proposed. As illustrative numerical examples, twenty jobs processing on a machine is considered. The feasibility and effectiveness of the proposed method have been demonstrated in the simulation. 展开更多
关键词 SCHEDULING single machine genetic algorithms fuzzy processing time multiple objectives
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A Recursive Method of Time-Frequency Analysis for the Signal Processing of Flutter Test with Progression Variable Speed 被引量:1
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作者 宋叔飚 裴承鸣 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第3期213-217,共5页
Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed (FTPVS), a new method of recursive time-frequency analysis is presented. The time-varying system is tr... Focused on the non-statlonarity and real-time analysis of signal in flutter test with progression variable speed (FTPVS), a new method of recursive time-frequency analysis is presented. The time-varying system is tracked on-line by building a time-varying parameter model, and then the relevant parameter spectrum can be obtained. The feasibility and advantages of the method are examined by digital simulation. The results of FTPVS at low-speed wind-tunnel promise the engineering application perspective of the method. 展开更多
关键词 flutter test with progression variable speed (FTPVS) non-stationary signal processing recursive time-frequency analysis (RTFA)
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A Class of Single Machine Scheduling Problemwith Variable Processing Time
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作者 ZHOU Xian-wei DU Wen LI Wen-quan 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第1期27-35,共9页
In this paper,single machine scheduling problems with variable processing time areraised.The criterions of the prolem considered are minimizing scheduling length of all jobs,flowtime and number of tardy jobs and so on... In this paper,single machine scheduling problems with variable processing time areraised.The criterions of the prolem considered are minimizing scheduling length of all jobs,flowtime and number of tardy jobs and so on.The complexity of the problem is determined. 展开更多
关键词 single machine scheduling problem:NP-hard variable processing time complexitytheory
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Modeling and Design of Real-Time Pricing Systems Based on Markov Decision Processes 被引量:4
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作者 Koichi Kobayashi Ichiro Maruta +1 位作者 Kazunori Sakurama Shun-ichi Azuma 《Applied Mathematics》 2014年第10期1485-1495,共11页
A real-time pricing system of electricity is a system that charges different electricity prices for different hours of the day and for different days, and is effective for reducing the peak and flattening the load cur... A real-time pricing system of electricity is a system that charges different electricity prices for different hours of the day and for different days, and is effective for reducing the peak and flattening the load curve. In this paper, using a Markov decision process (MDP), we propose a modeling method and an optimal control method for real-time pricing systems. First, the outline of real-time pricing systems is explained. Next, a model of a set of customers is derived as a multi-agent MDP. Furthermore, the optimal control problem is formulated, and is reduced to a quadratic programming problem. Finally, a numerical simulation is presented. 展开更多
关键词 MARKOV DECISION process OPTIMAL Control REAL-time PRICING System
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Range walk and array rotation in space-time adaptive processing:effects and compensations 被引量:2
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作者 Jinping Sun Guohua Wang Shiyi Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期537-543,共7页
This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing(STAP) in airborne multi-channel early-warning radar.Based on this clutter mod... This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing(STAP) in airborne multi-channel early-warning radar.Based on this clutter model,STAP performance is then analyzed from the perspective of covariance matrix tapering(CMT).For STAP performance degradation due to array rotation,a determinate compensation method is proposed based on the CMT method.Numerical examples are provided to verify the analysis and the proposed compensation method. 展开更多
关键词 RADAR space-time adaptive processing CLUTTER covariance matrix tapering.
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