期刊文献+
共找到3,723篇文章
< 1 2 187 >
每页显示 20 50 100
An Analysis of the Bidirectional Shaping Mechanism Between Short-Video Algorithms and Film Narrative Driven by the Attention Economy
1
作者 Zhaoyang Dong Shibo Zhang 《Proceedings of Business and Economic Studies》 2025年第5期32-38,共7页
This study examines the bidirectional shaping mechanism between short-video algorithms and film narratives within the attention economy.It investigates how algorithmic logic influences cinematic storytelling and how f... This study examines the bidirectional shaping mechanism between short-video algorithms and film narratives within the attention economy.It investigates how algorithmic logic influences cinematic storytelling and how films,in turn,contribute to the aesthetic enhancement of short-video content.Drawing on Communication Accommodation Theory and Berry’s Acculturation Theory,along with case analyses and industry data,this research demonstrates that algorithms push films toward high-stimulus,fast-paced narrative patterns—characterized by increased shot density and structural fragmentation—to capture and retain viewer attention.Conversely,films counter this influence by supplying narratively deep and artistically refined content that elevates short-video aesthetics and encourages critical audience engagement.This dynamic reflects a process of mutual adaptation rather than one-sided dominance.The study concludes that such interaction signifies a broader restructuring of cultural production logic,facilitating cross-media convergence while simultaneously posing risks to cultural diversity due to the prioritization of high-traffic content.Balancing this relationship will require policy support,algorithmic transparency,and strengthened industry self-regulation to preserve artistic integrity and cultural ecosystem diversity. 展开更多
关键词 Short-video algorithm Film narrative Bidirectional shaping Cultural production logic Attention economy
在线阅读 下载PDF
Integrating Value Shaping Into Task Design for Enhancing Ideological-Political Education in Foreign Language Courses
2
作者 CHEN Yan-hui 《Sino-US English Teaching》 2025年第2期53-57,共5页
The construction of ideological-political education within foreign language courses requires an integrated approach that encompasses value shaping,knowledge transfer,and competence cultivation.A critical challenge in ... The construction of ideological-political education within foreign language courses requires an integrated approach that encompasses value shaping,knowledge transfer,and competence cultivation.A critical challenge in this domain is the effective design and implementation of tasks that instill values,while also synergizing with acquiring knowledge and enhancing competencies.This paper delves into the philosophical underpinnings and operational principles of value-shaping task design and its practical application within the context of foreign language teaching.Utilizing Contemporary College English(Integrated Coursebook 3)as a case study,the paper explores value shaping-based task design in ideological-political education of foreign language courses,with the aim of providing references for the construction of ideological-political education in foreign language teaching. 展开更多
关键词 value shaping ideological-political construction foreign language course task design
在线阅读 下载PDF
Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
3
作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
在线阅读 下载PDF
Dynamic spatial beam shaping for ultrafast laser processing:a review
4
作者 Cyril Mauclair Bahia Najih +2 位作者 Vincent Comte Florent Bourquard Martin Delaigue 《Opto-Electronic Science》 2025年第8期14-43,共30页
This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strate... This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strategies and highlight the current limitations and challenges in surface and bulk processing.Specifically,we emphasize the delicate balance between high-fidelity beam shaping and energy efficiency,both critical for surface and bulk processing applications.Given the inherent physical limitations of spatial light modulators such as spatial resolution,fill factor,and phase modulation range.We explore techniques developed to bridge the gap between desired intensity distributions and actual experimental beam profiles.We present various laser light modulation technologies and the main algorithmic strategies for obtaining modulation patterns.The paper includes application examples across a wide range of fields,from surgery to surface structuring,cutting,bulk photo-inscription of optical functions,and additive manufacturing,highlighting the significant enhancements in processing speed and precision due to spatial beam shaping.The diverse applications and the technological limitations underscore the need for adapted modulation pattern calculation methods.We discuss several advancements addressing these challenges,involving both experimental and algorithmic developments,including the recent incorporation of artificial intelligence.Additionally,we cover recent progress in phase and pulse front control based on spatial modulators,which introduces an extra control parameter for light excitation with high potential for achieving more controlled processing outcomes. 展开更多
关键词 spatial light modulator ultrafast laser processing spatial beam shaping laser surface structuring laser bullk structuring
在线阅读 下载PDF
Discussion on Artistry and Techniques of Role Shaping in Drama Performance
5
作者 Ruixuan Liang 《Journal of Contemporary Educational Research》 2025年第5期326-331,共6页
Role shaping in dramatic performance is a fusion of art and skills,which involves the deep digging of character,the delicate expression of emotion,and the logical construction of behavior.Actors not only analyze the s... Role shaping in dramatic performance is a fusion of art and skills,which involves the deep digging of character,the delicate expression of emotion,and the logical construction of behavior.Actors not only analyze the script and understand the emotions of the role to create a multi-dimensional,three-dimensional character image,but also need to use the skills of sound,form,lines,and so on,to convey the role’s internal emotions and psychological changes.This process tests the artistic accomplishment and skill level of the actors,and requires them to have keen observation and rich imagination and creativity.Through the analysis of the role of Yu Ji in the Peking Opera Farewell My Concubine,it shows the deep integration of artistry and skill,highlighting the unique charm of dramatic performance. 展开更多
关键词 Role shaping Emotion expression Dramatic skill
在线阅读 下载PDF
Multiple Kalman filters model with shaping filter GPS real-time deformation analysis 被引量:6
6
作者 李丽华 彭军还 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3674-3681,共8页
In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GP... In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GPS real-time deformation series with a high sampling rate contain coloured noise, the multiple Kalman filter model requires the white noise, and the multiple Kalman filters model is augmented by a shaping filter in order to reduce the colored noise; secondly, the multiple Kalman filters model with shaping filter can detect the deformation epoch in real-time and improve the quality of GPS measurements for the real-time deformation applications. Based on the comparisons of the applications in different GPS time series with different models, the advantages of the proposed model were illustrated. The proposed model can reduce the colored noise, detect the smaller changes, and improve the precision of the detected deformation epoch. 展开更多
关键词 multiple Kalman filters model Kalman filter shaping filter deformation detection
在线阅读 下载PDF
Digitalization of inverting filter shaping circuit for nuclear pulse signals 被引量:9
7
作者 Huai-Qiang Zhang Hong-Tao Shi +1 位作者 Zhuo-Dai Li Yu-Wen Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第9期16-24,共9页
In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a ... In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping circuits.Because these circuits facilitate changing the phase of a pulse signal,they are widely used in processing nuclear pulse signals.In this study,the transfer functions of four types of inverting filter shaping circuits,namely the common inverting filter shaping,improved inverting filter shaping,multiple feedback low-pass filter shaping,and third-order multiple feedback low-pass filter shaping,in the Laplacian domain,are derived.We establish the numerical recursive function models and digitalize the four circuits,obtain the transfer functions in the Z domain,and analyze the filter performance and amplitude-frequency response characteristics in the frequency domain.Based on the actual nuclear pulse signal of the Si-PIN detector,we realize four types of inverting digital shaping.The results show that under the same shaping parameters,the common inverting digital shaping has better amplitude extraction characteristics,the third-order multiple feedback low-pass digital shaping has better noise suppression performance,and the multiple feedback digital shaping takes into account both pulse amplitude extraction and noise suppression performance. 展开更多
关键词 Nuclear pulse signal Inverting filter shaping circuit Digital shaping Amplitude-frequency response
在线阅读 下载PDF
Driving Behavior Shaping Model in Road Traffic System 被引量:2
8
作者 王武宏 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期331-336,共6页
In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analys... In order to give a new way for modeling driving behavior, identifying road traffic accident causation and solving a variety of road traffic safety problems such as driving errors prevention and driving behavior analysis, a new driving behavior shaping model is proposed, which could be used to assess the degree of effect of driving error upon road traffic safety. Driver behavior shaping model based on driving reliability and safety analysis could be used to identify the road traffic accident causation, to supply data for driver's behavior training, to evaluate driving procedures, to human factor design of road traffic system. 展开更多
关键词 driving errors driving behavior shaping factors driving reliability and safety analysis road traffic safety
在线阅读 下载PDF
A comparative study of optimization algorithms for wavefront shaping 被引量:4
9
作者 Zahra Fayyaz Nafiseh Mohammadian +2 位作者 M.Reza Rahimi Tabar Rayyan Manwar Kamran(Mohammad)Avanaki 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第4期74-82,共9页
By manipulating the phase map of a wavefront of light using a spatial light modulator,the scattered light can be sharply focused on a specific target.Several iterative optimization algo-rithrns for obtaining the optim... By manipulating the phase map of a wavefront of light using a spatial light modulator,the scattered light can be sharply focused on a specific target.Several iterative optimization algo-rithrns for obtaining the optimumn phase map have been explored.However,there has not been a comparative study on the performance of these algorithms.In this paper,six optimization algorithms for wavefront shaping inchuding continuous sequential,partitioning algorithm,transmission matrix estimation method,particle swarm optimization,genetic algorithm(GA),and simulated annealing(SA)are discussed and compared based on their efficiency when introduced with various measurement noise levels. 展开更多
关键词 Wave front shaping algorithms OPTIMIZATION turbid media wavefront shaping
原文传递
Seismic attenuation compensation with spectral-shaping regularization
10
作者 QiZhen Du WanYu Wang +1 位作者 WenHan Sun Li-Yun Fu 《Earth and Planetary Physics》 EI CSCD 2022年第3期259-274,共16页
Because of the viscoelasticity of the subsurface medium,seismic waves will inherently attenuate during propagation,which lowers the resolution of the acquired seismic records.Inverse-Q filtering,as a typical approach ... Because of the viscoelasticity of the subsurface medium,seismic waves will inherently attenuate during propagation,which lowers the resolution of the acquired seismic records.Inverse-Q filtering,as a typical approach to compensating for seismic attenuation,can efficiently recover high-resolution seismic data from attenuation.Whereas most efforts are focused on compensating for highfrequency energy and improving the stability of amplitude compensation by inverse-Q filtering,low-frequency leakage may occur as the high-frequency component is boosted.In this article,we propose a compensation scheme that promotes the preservation of lowfrequency energy in the seismic data.We constructed an adaptive shaping operator based on spectral-shaping regularization by tailoring the frequency spectra of the seismic data.We then performed inverse-Q filtering in an inversion scheme.This data-driven shaping operator can regularize and balance the spectral-energy distribution for the compensated records and can maintain the low-frequency ratio by constraining the overcompensation for high-frequency energy.Synthetic tests and applications on prestack common-reflectionpoint gathers indicated that the proposed method can preserve the relative energy of low-frequency components while fulfilling stable high-frequency compensation. 展开更多
关键词 seismic attenuation compensation spectral-shaping regularization data-driven shaping operator offset-related inverse-Q filter
在线阅读 下载PDF
Numerical Simulation of Multi-track and Multi-layer Temperature Field on Laser Direct Metal Shaping 被引量:8
11
作者 LONG Risheng~(1,2) LIU Weijun~1 (1.Advanced Manufacture Lab,Shenyang Institute of Automation,Shenyang 110016,China, 2.Graduate School,Chinese Academy of Sciences,Beijing 100039,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期1111-1116,共6页
To improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping(LDMS),it is of great significance to understand the distribution regularities of transient temperature field during LDMS proce... To improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping(LDMS),it is of great significance to understand the distribution regularities of transient temperature field during LDMS process.Based on the“el- ement birth and death”technique of finite element method,a three-dimensional multi-track and multi-layer model for the transient temperature field analysis of LDMS is developed by ANSYS Parametric Design Language(APDL)for the first time.In the fab- ricated modal,X-direction parallel reciprocating scanning paths is introduced.Using the same process parameters,the simulation results show good agreement with the microstructure features of samples which fabricated by LDMS. 展开更多
关键词 LASER DIRECT METAL shaping transient temperature field numerical simulation
在线阅读 下载PDF
Convex shaping process simulation during counter-rotating electrochemical machining by using the finite element method 被引量:11
12
作者 Wang Dengyong Zhu Zengwei +1 位作者 Wang Hongrui Zhu Di 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第2期534-541,共8页
In counter-rotating electrochemical machining (CRECM), a revolving cathode tool with hollow windows of various shapes is used to fabricate convex structures on a revolving part. During this process, the anode workpi... In counter-rotating electrochemical machining (CRECM), a revolving cathode tool with hollow windows of various shapes is used to fabricate convex structures on a revolving part. During this process, the anode workpiece and the cathode tool rotate relative to each other at the same rotation speed. In contrast to the conventional schemes of ECM machining with linear motion of a block tool electrode, this scheme of ECM is unique, and has not been adequately studied yet. In this paper, the finite element method (FEM) is used to simulate the anode shaping process during CRECM, and the simulation process which involves a meshing model, a moving boundary, and a simulation algorithm is described. The simulated anode profiles of the convex structure at different processing times show that the CRECM process can be used to fabricate convex structures of various shapes with different heights. Besides, the variation of the inter-electrode gap indicates that this process can also reach a relative equilibrium state like that in conventional ECM. A rectangular convex and a circular convex are successfully fabricated on revolving parts. The experimental results indicate relatively good agreement with the simulation results. The proposed simulation process is valid for convex shaping prediction and feasibility studies as well. 展开更多
关键词 COUNTER-ROTATING Convex shaping process Electrochemical machining Finite element method Inter-electrode gap
原文传递
Additive Manufacturing of Ceramic Structures by Laser Engineered Net Shaping 被引量:8
13
作者 NIU Fangyong WU Dongjiang +1 位作者 MA Guangyi ZHANG Bi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第6期1117-1122,共6页
Ceramic is an important material with outstanding physical properties whereas impurities and porosities generated by traditional manufacturing methods limits its further industrial applications.In order to solve this ... Ceramic is an important material with outstanding physical properties whereas impurities and porosities generated by traditional manufacturing methods limits its further industrial applications.In order to solve this problem,direct fabrication of Al2O3 ceramic structures is conducted by laser engineered net shaping system and pure ceramic powders.Grain refinement strengthening method by doping Zr O2 and dispersion strengthening method by doping Si C are proposed to suppress cracks in fabricating Al2O3 structure.Phase compositions,microstructures as well as mechanical properties of fabricated specimens are then analyzed.The results show that the proposed two methods are effective in suppressing cracks and structures of single-bead wall,arc and cylinder ring are successfully deposited.Stable phase ofα-Al2O3 and t-Zr O2 are obtained in the fabricated specimens.Micro-hardness higher than 1700 HV are also achieved for both Al2O3 and Al2O3/Zr O2,which are resulted from fine directional crystals generated by the melting-solidification process.Results presented indicate that additive manufacturing is a very attractive technique for the production of high-performance ceramic structures in a single step. 展开更多
关键词 LASERS net shaping ALUMINA CERAMICS additive manufacturing
在线阅读 下载PDF
Shaping Taste: The Molecular Discovery of Rice Genes Improving Grain Size, Shape and Quality 被引量:7
14
作者 Nicholas P.Harberd 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2015年第11期597-599,共3页
Modern-day human life is absolutely dependent upon the food that we derive from our crop plants. We eat grains, fruits, roots, tubers and other structures, all of which are constructed via coordinated organ growth. Wh... Modern-day human life is absolutely dependent upon the food that we derive from our crop plants. We eat grains, fruits, roots, tubers and other structures, all of which are constructed via coordinated organ growth. Whilst plant organ identity is first established in apical meristems (vegetative and floral shoot meristems and root meristems), and in other meristematic regions, the final size and shape of organs are defined by subsequent coordination of organ expansion in longitudinal and transverse axes. 展开更多
关键词 QTLs shaping Taste The Molecular Discovery of Rice Genes Improving Grain Size Shape and Quality gene
原文传递
Preparation and shaping of solid acid SO_4^(2-)/TiO_2 and its application for esterification of propylene glycol monomethyl ether and acetic acid 被引量:8
15
作者 Zhixian Huang Yixiong Lin +2 位作者 Ling Li Changshen Ye Ting Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第9期1207-1216,共10页
The solid acid SO_4^(2-)/TiO_2 was prepared by immersion method and applied for synthesis of propylene glycol methyl ether acetate(PMA) through esterification reaction of propylene glycol monomethyl ether(PM)and aceti... The solid acid SO_4^(2-)/TiO_2 was prepared by immersion method and applied for synthesis of propylene glycol methyl ether acetate(PMA) through esterification reaction of propylene glycol monomethyl ether(PM)and acetic acid(HAc). The optimal catalyst preparation condition was determined by orthogonal analysis of parameters in a five-factor and four-level test. The obtained solid acid catalysts were characterized in detail by means of X-ray powder diffraction, thermogravimetry, pyridine adsorbed IR analysis, scanning electron microscopy, and BET surface area method. Synthesis of PMA was studied in this paper through experimental investigation of reaction conditions such as temperature, molar ratio of reactants, catalyst dosage and agitation speed. Based on its possible reaction mechanism, a pseudo-homogeneous kinetic model was established and its activation energies E_a^+ and E_a^-,65.68 × 10~3J·mol^(-1) and 57.78 × 10~3J·mol^(-1), were estimated. To prepare shaped solid acid catalyst SO_4^(2-)/TiO_2, the shaping method of impregnation–shaping–impregnation was applied. The optimal molding formulation of solid acid catalyst, obtained from the orthogonal test, was found to be binder 7 wt%, reinforcing agent 20 wt%, pore forming material 2.5 wt%, and lubricant 4 wt%.The results of performance test of catalyst demonstrated that the shaped solid acid catalyst exhibited high activity and stability. 展开更多
关键词 Propylene glycol methyl ether acetate Solid acid shaping Kinetic modeling
在线阅读 下载PDF
Application of pole-zero cancellation circuit in nuclear signal filtering and shaping algorithm 被引量:9
16
作者 Huai-Ping Wang Jian-Bin Zhou +5 位作者 Xiao-Ping Ouyang Xian-Guo Tuo Xu Hong Yi Liu Jie Yu You-Xian Jin 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第8期85-94,共10页
In radiation measurement and digital nuclear spectrum systems,traditional nuclear signal processing circuits in nuclear electronics have been gradually replaced by digital algorithm modules with the application of hig... In radiation measurement and digital nuclear spectrum systems,traditional nuclear signal processing circuits in nuclear electronics have been gradually replaced by digital algorithm modules with the application of highperformance programmable hardware logic devices(such as FPGA or DSP).Referring to the digital realization method of inverse RC integral circuit systems,the function of the pole-zero cancellation(PZC)circuit was analyzed,a new modified cascade equivalent model of PZC was established,and the time-domain digital PZC(DPZC)recursive algorithm was derived in detail in this study.Two parameters kIand k_(D)are included in the new algorithm,where kIshould match the exponential decay time constant of the input signal to realize the pole-zero compensation,while the decay time constant of the output signal can be changed with the adjustable parameter k_(D)(which is larger than the decay time constant of the input signal).Based on the new DPZC algorithm module,two trapezoidal(triangular)shaping filters were designed and implemented.The amplitude–frequency characteristics of the output signal of the proposed trapezoidal shaping algorithm and the convolution trapezoidal shaping algorithm were compared,with fixed peaking time.The results show that the trapezoidal shaping algorithm based on DPZC can better suppress high-frequency noise.Finally,based on the Na I(Tl)scintillator(u75 mm×75 mm)detector and^(137)Cs source,the effect of the k_(D)value on the energy resolution of the DPZC trapezoidal(triangular)shaping algorithm was studied.The experimental results show that,with an increase in k_(D),the energy resolution of the system improved and reached the maximum when k_(D)was greater than 10,and the optimal energy resolution of the system was 7.72%. 展开更多
关键词 Pole-zero cancellation C–R inverse system Trapezoidal/triangular shaping Amplitude–frequency characteristics Energy resolution
在线阅读 下载PDF
Signal modeling and impulse response shaping for semiconductor detectors 被引量:7
17
作者 Xue-Yuan Wang Jian-Bin Zhou +4 位作者 Ming Wang Huai-Ping Wang Xu Hong Yi Liu Ping Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第4期72-82,共11页
The output-signal models and impulse response shaping(IRS)functions of semiconductor detectors are important for establishing high-precision measurement systems.In this paper,an output-signal model for semiconductor d... The output-signal models and impulse response shaping(IRS)functions of semiconductor detectors are important for establishing high-precision measurement systems.In this paper,an output-signal model for semiconductor detector systems is proposed.According to the proposed model,a multistage cascade deconvolution IRS algorithm was developed using the C-R inverse system,R-C inverse system,and differentiator system.The silicon drift detector signals acquired from the analog-to-digital converter were tested.The experimental results indicated that the shaped pulses obtained using the proposed model had no undershoot,and the average peak base width of the output shaped pulses was reduced by 36%compared with that for a simple model proposed in a previous work[1].Offline processing results indicated that compared with the traditional IRS algorithm,the average peak base width of the output shaped pulses obtained using the proposed algorithm was reduced by 11%,and the total elapsed time required for pulse shaping was reduced by 26%.The proposed algorithm avoids recursive calculation.If the sampling frequency of the digital system reaches 100 MHz,the proposed algorithm can be simplified to integer arithmetic.The proposed IRS algorithm can be applied to high-resolution energy spectrum analysis,highcounting rate energy spectrum correction,and coincidence and anti-coincidence measurements. 展开更多
关键词 Output-signal model Impulse response shaping C-R inverse system R-C inverse system Integer arithmetic
在线阅读 下载PDF
Time-to-go weighted optimal trajectory shaping guidance law 被引量:7
18
作者 王辉 林德福 程振轩 《Journal of Beijing Institute of Technology》 EI CAS 2011年第3期317-323,共7页
For maneuvering target, the optimal trajectory shaping guidance law which can simultaneously achieve the designed specifications on miss distance and final impact angle was deduced using optimal control theory based o... For maneuvering target, the optimal trajectory shaping guidance law which can simultaneously achieve the designed specifications on miss distance and final impact angle was deduced using optimal control theory based on the time-to-go weighted function. Based on the same cost function, the closed-form solutions of the guidance law were derived when the initial displacement of missile, final impact angle, heading error and target maneuver was introduced into the lag-free guidance system. To validate the closed-form solutions, the simulation of the lag-free system was done and the simulation results exactly matched the closed-form solutions and only when the exponent is greater than zero, the final acceleration approaches to zero. 展开更多
关键词 trajectory shaping guidance optimal control TIME-TO-GO close-form solution
在线阅读 下载PDF
Shaping of metal-organic frameworks through a calcium alginate method towards ethylene/ethane separation 被引量:4
19
作者 Jinlong Li Xiaoqing Wang +3 位作者 Puxu Liu Xiaohua Liu Libo Li Jinping Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期17-24,共8页
The separation of ethylene and ethane is a crucial,challenging and cost-intensive process in chemical engineering.Metal-organic frameworks(MOFs)are a class of novel porous adsorbents used for the separation of ethylen... The separation of ethylene and ethane is a crucial,challenging and cost-intensive process in chemical engineering.Metal-organic frameworks(MOFs)are a class of novel porous adsorbents used for the separation of ethylene/ethane mixtures.However,MOFs are normally crystalline powders that cause multiple problems,such as dust,abrasion and heat/mass loss,as well as significant pressure drops on the adsorption bed resulting in a sudden stop in production.To solve these issues,we have prepared four different sphere-shaped adsorbents,including Mg-gallate,Co-gallate,MUV-10(Mn)and MIL-53(Al)using a calcium alginate method to achieve excellent ethylene/ethane separation performance.The performance of the sphere-shaped adsorbents has been validated using mechanical strength measurements,powder X-ray diffraction,scanning electron microscopy,thermogravimetric analysis,gas adsorption isotherms and dynamic breakthrough experiments.The excellent mechanical strength of these sphere-shaped adsorbents meets the criteria for industrial application in gas separation.Thus,the energy consumption and operating cost will be further reduced in the ethylene production process.We believe that this shaping method will open a prosperous route to the development of MOFs toward higher technology levels and their commercial application. 展开更多
关键词 Metal-organic frameworks Alginates shaping Mechanical properties ADSORPTION SEPARATION
在线阅读 下载PDF
A thorough study on genetic algorithms in feedback-based wavefront shaping 被引量:5
20
作者 Daixuan Wu Jiawei Luo +1 位作者 Zhaohui Li Yuecheng Shen 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第4期94-104,共11页
Feedback-based wavefront shaping focuses light through scattering media by employing phase optimization algorithms.Genetic algorithms(GAs),inspired by the process of natural selection,are well suited for phase optimiz... Feedback-based wavefront shaping focuses light through scattering media by employing phase optimization algorithms.Genetic algorithms(GAs),inspired by the process of natural selection,are well suited for phase optimization in wavelfront shaping problems.In 2012,Conkey et al.first introduced a GA into feedback-based wavefront shaping to find the optimum phase map.Since then,due to its siuperior performance in noisy environment,the GA has been widely adopted by lots of implementations.However,there have been limited studies discussing and optimizing the detailed procedures of the GA.To fill this blank,in this study,we performed a thorough study on the performance of the GA for focusing light through scattering media.Using numerical tools,we evaluated certain procedures that can be potentially improved and provided guidance on how to choose certain parameters appropriately.This study is beneficial in improving the performance of wavefront shaping systems with GAs. 展开更多
关键词 Genetice algorithm wavefront shaping scattering media adaptive optics
原文传递
上一页 1 2 187 下一页 到第
使用帮助 返回顶部