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Near-Infrared Transit Photometry of Extra-Solar Planet HAT-P-54b 认领
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作者 Yoichi Itoh 《天文学与天体物理学国际期刊(英文)》 2020年第2期89-96,共8页
The results of near-infrared photometric observations of a transit event of an extrasolar planet HAT-P-54b are presented herein. Precise near-infrared photometry was carried out using the Nayuta 2 m telescope at Nishi... The results of near-infrared photometric observations of a transit event of an extrasolar planet HAT-P-54b are presented herein. Precise near-infrared photometry was carried out using the Nayuta 2 m telescope at Nishi-Harima Astronomical Observatory, Japan and Nishi-Harima Infrared Camera (NIC). 170 <em>J-</em>, <em>H-</em>, and <em>Ks</em>-band images were taken in each band in 196 minutes. The flux of the planetary system was observed to decrease during the transit event. While the <em>Ks</em>-band transit depth is similar to that in the <em>r</em>-band, the<em> J</em>- and <em>H</em>-band transits are deeper than those in the <em>Ks</em>-band. We constructed simple models of the planetary atmosphere and found that the observed transit depths are well reproduced by inflated atmosphere containing H<sub>2</sub>S molecule. 展开更多
关键词 Planetary Systems Infrared: Planetary Systems
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耦合魔方——一个分析人地系统耦合机理的多维框架 认领
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作者 刘海猛 方创琳 方恺 《地理学报:英文版》 SCIE CSCD 2020年第3期355-377,共23页
Understanding the interactions between humans and nature in the Anthropocene is central to the quest for both human wellbeing and global sustainability.However,the time-space compression,long range interactions,and re... Understanding the interactions between humans and nature in the Anthropocene is central to the quest for both human wellbeing and global sustainability.However,the time-space compression,long range interactions,and reconstruction of socio-economic structures at the global scale all pose great challenges to the traditional analytical frameworks of human-nature systems.In this paper,we extend the connotation of coupled human and natural systems(CHANS)and their four dimensions—space,time,appearance,and organization,and propose a novel framework:“Coupled Human and Natural Cube”(CHNC)to explain the coupling mechanism between humans and the natural environment.Our proposition is inspired by theories based on the human-earth areal system,telecoupling framework,planetary urbanization,and perspectives from complexity science.We systematically introduce the concept,connotation,evolution rules,and analytical dimensions of the CHNC.Notably there exist various“coupling lines”in the CHNC,connecting different systems and elements at multiple scales and forming a large,nested,interconnected,organic system.The rotation of the CHNC represents spatiotemporal nonlinear fluctuations in CHANS in different regions.As a system continually exchanges energy with the environment,a critical phase transition occurs when fluctuations reach a certain threshold,leading to emergent behavior of the system.The CHNC has four dimensions—pericoupling and telecoupling,syncoupling and lagcoupling,apparent coupling and hidden coupling,and intra-organization coupling and inter-organizational coupling.We mainly focus on the theoretical connotation,research methods,and typical cases of telecoupling,lagcoupling,hidden coupling,and inter-organizational coupling,and put forward a human-nature coupling matrix to integrate multiple dimensions.In summary,the CHNC provides a more comprehensive and systematic research paradigm for understanding the evolution and coupling mechanism of the human-nature system,which expands the analytical dimension of CHA 展开更多
关键词 Coupled Human and Natural Cube human-environment systems social-ecological systems pericoupling and telecoupling climate change URBANIZATION human activity complexity science sustainability science
Abiotic-Biological Hybrid Systems for CO2 Conversion to Value-Added Chemicals and Fuels 认领
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作者 Jiansheng Li Yao Tian +5 位作者 Yinuo Zhou Yongchao Zong Nan Yang Mai Zhang Zhiqi Guo Hao Song 《天津大学学报:英文版》 EI CAS 2020年第4期237-247,共11页
Abiotic-biological hybrid systems that combine the advantages of abiotic catalysis and biotransformation for the conversion of carbon dioxide(CO2)to value-added chemicals and fuels have emerged as an appealing way to ... Abiotic-biological hybrid systems that combine the advantages of abiotic catalysis and biotransformation for the conversion of carbon dioxide(CO2)to value-added chemicals and fuels have emerged as an appealing way to address the global energy and environmental crisis caused by increased CO2 emission.We illustrate the recent progress in this field.Here,we first review the natural CO2 fixation pathways for an in-depth understanding of the biological CO2 transformation strategy and why a sustainable feed of reducing power is important.Second,we review the recent progress in the construction of abiotic-biological hybrid systems for CO2 transformation from two aspects:(i)microbial electrosynthesis systems that utilize electricity to support whole-cell biological CO2 conversion to products of interest and(ii)photosynthetic semiconductor biohybrid systems that integrate semiconductor nanomaterials with CO2-fixing microorganisms to harness solar energy for biological CO2 transformation.Lastly,we discuss potential approaches for further improvement of abiotic-biological hybrid systems. 展开更多
关键词 CO2 conversion Abiotic-biological hybrid systems Microbial electrosynthesis systems Photosynthetic semiconductor biohybrid systems
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Energy Efficient Scheduler of Aperiodic Jobs for Real-time Embedded Systems 认领
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作者 Hussein El Ghor El-Hadi MAggoune 《国际自动化与计算杂志:英文版》 EI CSCD 2020年第5期733-743,共11页
Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of execution.Schedulability improvement is no l... Energy consumption has become a key metric for evaluating how good an embedded system is,alongside more performance metrics like respecting operation deadlines and speed of execution.Schedulability improvement is no longer the only metric by which optimality is judged.In fact,energy efficiency is becoming a preferred choice with a fundamental objective to optimize the system's lifetime.In this work,we propose an optimal energy efficient scheduling algorithm for aperiodic real-time jobs to reduce CPU energy consumption.Specifically,we apply the concept of real-time process scheduling to a dynamic voltage and frequency scaling(DVFS)technique.We address a variant of earliest deadline first(EDF)scheduling algorithm called energy saving-dynamic voltage and frequency scaling(ES-DVFS)algorithm that is suited to unpredictable future energy production and irregular job arrivals.We prove that ES-DVFS cannot attain a total value greater than C/ˆSα,whereˆS is the minimum speed of any job and C is the available energy capacity.We also investigate the implications of having in advance,information about the largest job size and the minimum speed used for the competitive factor of ES-DVFS.We show that such advance knowledge makes possible the design of semi-on-line algorithm,ES-DVFS∗∗,that achieved a constant competitive factor of 0.5 which is proved as an optimal competitive factor.The experimental study demonstrates that substantial energy savings and highest percentage of feasible job sets can be obtained through our solution that combines EDF and DVFS optimally under the given aperiodic jobs and energy models. 展开更多
关键词 Real-time systems energy efficiency aperiodic jobs SCHEDULING dynamic voltage scaling low-power systems embedded systems
船舶管路系统中与压力有关的模型研究 认领
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作者 Daniel Molina Pérez Lemuel C.Ramos-Arzola Amadelis Quesada Torres 《船舶与海洋工程学报:英文版》 CSCD 2020年第2期266-274,共9页
This paper aims to evaluate the feasibility of pressure-dependent models in the design of ship piping systems.For this purpose,a complex ship piping system is designed to operate in firefighting and bilge services thr... This paper aims to evaluate the feasibility of pressure-dependent models in the design of ship piping systems.For this purpose,a complex ship piping system is designed to operate in firefighting and bilge services through jet pumps.The system is solved as pressure-dependent model by the piping system analysis software EPANET and by a mathematical approach involving a piping network model.This results in a functional system that guarantees the recommendable ranges of hydraulic state variables(flow and pressure)and compliance with the rules of ship classification societies.Through this research,the suitability and viability of pressure-dependent models in the simulation of a ship piping system are proven. 展开更多
关键词 Pressure-dependent models Ship piping systems Bilge systems Firefighting systems Piping network models
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Structural Properties of Homomorphism Dilation Systems 认领
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作者 Deguang HAN David R.LARSON +1 位作者 Bei LIU Rui LIU 《数学年刊:B辑英文版》 SCIE CSCD 2020年第4期585-600,共16页
Inspired by some recent development on the theory about projection valued dilations for operator valued measures or more generally bounded homomorphism dilations for bounded linear maps on Banach algebras,the authors ... Inspired by some recent development on the theory about projection valued dilations for operator valued measures or more generally bounded homomorphism dilations for bounded linear maps on Banach algebras,the authors explore a pure algebraic version of the dilation theory for linear systems acting on unital algebras and vector spaces.By introducing two natural dilation structures,namely the canonical and the universal dilation systems,they prove that every linearly minimal dilation is equivalent to a reduced homomorphism dilation of the universal dilation,and all the linearly minimal homomorphism dilations can be classified by the associated reduced subspaces contained in the kernel of synthesis operator for the universal dilation. 展开更多
关键词 Linear systems Linearly minimal homomorphism dilation systems Principle and universal dilations Equivalent dilation systems
Performance Improvement of Discrete-time Linear Control Systems Subject to Varying Sampling Rates Using the Tikhonov Regularization Method 认领
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作者 Fernando Agustin Pazos Anibal Zanini Amit Bhaya 《国际自动化与计算杂志:英文版》 EI CSCD 2020年第3期453-463,共11页
Methods to stabilize discrete-time linear control systems subject to variable sampling rates,i.e.,using state feedback controllers,are well known in the literature.Several recent works address the use of the Tikhonov ... Methods to stabilize discrete-time linear control systems subject to variable sampling rates,i.e.,using state feedback controllers,are well known in the literature.Several recent works address the use of the Tikhonov regularization method,originally designed to attenuate the noise effects on ill-posed problems,with the aim of improving performance and stabilizing approximately controllable dynamical systems.Inspired by these works,we propose the use of a feedback controller designed using the Tikhonov method to regularize discrete-time linear systems subject to varying sampling rates.The goal is to minimize an error function,thus improving the performance of the closed loop system and reducing the possibility of instability.Illustrative examples show the effectiveness of the proposed method. 展开更多
关键词 Discrete-time switched systems Tikhonov regularization varying sampling rates discrete-time control systems networked control systems
文章速递Hepatocellular carcinoma Liver Imaging Reporting and Data Systems treatment response assessment: Lessons learned and future directions 认领
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作者 Anum Aslam Richard Kinh Gian Do +7 位作者 Avinash Kambadakone Bradley Spieler Frank H Miller Ahmed M Gabr Resmi A Charalel Charles Y Kim David C Madoff Mishal Mendiratta-Lala 《世界肝病学杂志:英文版(电子版)》 CAS 2020年第10期738-753,共16页
Hepatocellular carcinoma(HCC)is a leading cause of morbidity and mortality worldwide,with rising clinical and economic burden as incidence increases.There are a multitude of evolving treatment options,including locore... Hepatocellular carcinoma(HCC)is a leading cause of morbidity and mortality worldwide,with rising clinical and economic burden as incidence increases.There are a multitude of evolving treatment options,including locoregional therapies which can be used alone,in combination with each other,or in combination with systemic therapy.These treatment options have shown to be effective in achieving remission,controlling tumor progression,improving disease free and overall survival in patients who cannot undergo resection and providing a bridge to transplant by debulking tumor burden to downstage patients.Following locoregional therapy(LRT),it is crucial to provide treatment response assessment to guide management and liver transplant candidacy.Therefore,Liver Imaging Reporting and Data Systems(LI-RADS)Treatment Response Algorithm(TRA)was created to provide a standardized assessment of HCC following LRT.LIRADS TRA provides a step by step approach to evaluate each lesion independently for accurate tumor assessment.In this review,we provide an overview of different locoregional therapies for HCC,describe the expected post treatment imaging appearance following treatment,and review the LI-RADS TRA with guidance for its application in clinical practice.Unique to other publications,we will also review emerging literature supporting the use of LI-RADS for assessment of HCC treatment response after LRT. 展开更多
关键词 Hepatocellular carcinoma Liver Imaging Reporting and Data Systems Treatment Response Algorithm Locoregional therapy Liver Imaging Reporting and Data Systems Treatment Response equivocal Arterial phase hyper enhancement Stereotactic body radiotherapy
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文章速递Event-Triggered Finite-Time <i>H</i><sub>∞</sub>Control for Switched Stochastic Systems 认领
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作者 Aiqing Zhang 《应用数学与应用物理(英文)》 2020年第10期2103-2114,共12页
This paper investigates the problem of event-triggered finite-time <i>H</i><sub>∞</sub> control for a class of switched stochastic systems. The main objective of this study is to design an eve... This paper investigates the problem of event-triggered finite-time <i>H</i><sub>∞</sub> control for a class of switched stochastic systems. The main objective of this study is to design an event-triggered state feedback <i>H</i><sub>∞</sub> controller such that the resulting closed-loop system is finite-time bounded and satisfies a prescribed <i>H</i><sub>∞</sub> level in some given finite-time interval. Based on stochastic differential equations theory and average dwell time approach, sufficient conditions are derived to ensure the finite-time stochastic stability with the prescribed <i>H</i><sub>∞</sub> performance for the relevant closed-loop system by employing the linear matrix inequality technique. Finally, the desired state feedback <i>H</i><sub>∞</sub> controller gain matrices can be expressed in an explicit form. 展开更多
关键词 Average Dwell Time Event-Triggering Scheme Finite-Time Stochastic Stability (FTSS) Linear Matrix Inequalities (LMIS) Switched Stochastic Systems
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Most Intense X-Ray Lines of the Helium Isoelectronic Sequence for Plasmas Diagnostic 认领
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作者 Ibrahima Sakho 《现代物理(英文)》 2020年第4期487-501,共15页
We report accurate wavelengths for the three most intense lines (resonance line: 1s2 1S0 - 1s2p 1P1, intercombination line: 1s2 1S0 - 1s2p 3P1 and forbidden line: 1s2 1S0 - 1s2s 3S1) along with wavelengths for the 1s2... We report accurate wavelengths for the three most intense lines (resonance line: 1s2 1S0 - 1s2p 1P1, intercombination line: 1s2 1S0 - 1s2p 3P1 and forbidden line: 1s2 1S0 - 1s2s 3S1) along with wavelengths for the 1s2 1S0 - 1snp1P1 and 1S0 - 1snp3P2 (2 ≤ n ≤ 25) transitions in He-like systems (Z = 2 – 13). The first spectral lines that belong to the above transitions are established in the framework of the Screening Constant per Unit Nuclear Charge method. The results obtained agree excellently with various experimental and theoretical literature data. The uncertainties in wavelengths between the present calculations and the available literature data are less than 0.004&Aring;. A host of new data listed in this paper may be of interest in astrophysical and laboratory plasmas diagnostic. 展开更多
关键词 HE-LIKE Systems SEMI-EMPIRICAL Screening Constant Per Unit Nuclear Charge Excited States X-RAY Spectra
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Global Sensitivity Analysis in Physiological Systems 认领
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作者 Tahmineh Azizi Robert Mugabi 《应用数学(英文)》 2020年第3期119-136,共18页
Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that ... Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that caused to do a lot of efforts to make them more accurate. Current work studies the process of drug and nanoparticle (NPs) distribution throughout the body which consists of a system of ordinary differential equations. We use a tri-compartmental model to study the perfusion of NPs in tissues and a six-compartmental model to study drug distribution in different body organs. We have performed global sensitivity analysis by LHS Monte Carlo method using PRCC. We identify the key parameters that contribute most significantly to the absorption and distribution of drugs and NPs in different organs in body. 展开更多
关键词 Global Sensitivity Analysis LATIN HYPERCUBE Sampling (LHS) Partial RANK Correlation Coefficient (PRCC) PHYSIOLOGICAL Systems Drug and NPS Distribution
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Affine transformation based formation maneuvering for discrete-time directed networked systems 认领
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作者 XU Yang LUO DeLin +1 位作者 YOU YanCheng DUAN HaiBin 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第1期73-85,共13页
For the tracking control problems of affine formation maneuvers with discrete leader-following multi-agent systems, various distributed control schemes based on the directed graphs are designed in this paper. Consider... For the tracking control problems of affine formation maneuvers with discrete leader-following multi-agent systems, various distributed control schemes based on the directed graphs are designed in this paper. Consider the single and double-integrator models, different types of formation maneuvers can be achieved subject to the states of leaders with the novel characteristic of affine localizability. Meanwhile, the properties of affine transformation and signed Laplacian are introduced, which simplify the structures of controllers with distinct constraints to a great extent. Moreover, the convergence analysis of proposed protocols is proven. Static, constant and time-varying target formations can be tracked successfully. In the end, corresponding numerical simulations are carried out to certify the validity of theoretical results. 展开更多
关键词 multi-agent SYSTEMS AFFINE formation MANEUVER discrete SYSTEMS directed graph SIGNED LAPLACIAN
3D Physical Simulation of Water Flooding Characteristics of Buried Hill Reservoir with Different Fracture Systems 认领
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作者 Xiaolin Zhu Zhiqiang Meng +2 位作者 Pingzhi Gong Guanglong Li Xinran Wang 《电力能源(英文)》 2020年第5期1-13,共13页
In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional ... In order to understand the water-flooding characteristics of different fracture systems in metamorphic rock buried hill reservoirs and the mechanism of improving water-flooding development effect, a three-dimensional physical model of fractured reservoirs is established according to the similarity criterion based on the prototype of metamorphic buried hill reservoirs in JZ Oilfield in Bohai Bay Basin. Combined with the fractured reservoir characteristics of JZ Oilfield, the water displacement characteristics of the top-bottom staggered injection-production well pattern in different fracture network mode and different fracture development degree of buried hill reservoir are studied. The experimental results show that: 1) the more serious the fracture system irregularity is, the shorter the water-free oil production period is and the lower the water-free oil recovery is. After water breakthrough of production wells, the water cut rises faster, and the effect of water flooding development is worse;2) under the condition of non-uniform fracture development, the development effect of the bottom fracture undeveloped is better than that of the middle fracture undeveloped. Water injection wells are deployed in areas with relatively few fractures, while oil wells are deployed in fractured areas with higher oil recovery and better development effect. 展开更多
关键词 METAMORPHIC Buried Hill Reservoir DIFFERENT FRACTURE SYSTEMS 3D Physical Simulation Water FLOODING CHARACTERISTICS
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Resilient Fault Diagnosis Under Imperfect Observations–A Need for Industry 4.0 Era 认领
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作者 Alejandro White Ali Karimoddini Mohammad Karimadini 《自动化学报:英文版》 SCIE EI CSCD 2020年第5期1279-1288,共10页
In smart industrial systems,in many cases,a fault can be captured as an event to represent the distinct nature of subsequent changes.Event-based fault diagnosis techniques are capable model-based methods for diagnosin... In smart industrial systems,in many cases,a fault can be captured as an event to represent the distinct nature of subsequent changes.Event-based fault diagnosis techniques are capable model-based methods for diagnosing faults from a sequence of observable events executed by the system under diagnosis.Most event-based diagnosis techniques rely on perfect observations of observable events.However,in practice,it is common to miss an observable event due to a problem in sensorreadings or communication/transmission channels.This paper develops a fault diagnosis tool,referred to as diagnoser,which can robustly detect,locate,and isolate occurred faults.The developed diagnoser is resilient against missed observations.A missed observation is detected from its successive sequence of events.Upon detecting a missed observation,the developed diagnoser automatically resets and then,asynchronously resumes the diagnosis process.This is achieved solely based on postreset/activation observations and without interrupting the performance of the system under diagnosis.New concepts of asynchronous detectability and asynchronous diagnosability are introduced.It is shown that if asynchronous detectability and asynchronous diagnosability hold,the proposed diagnoser is capable of diagnosing occurred faults under imperfect observations.The proposed technique is applied to diagnose faults in a manufacturing process.Illustrative examples are provided to explain the details of the proposed algorithm.The result paves the way towards fostering resilient cyber-physical systems in Industry4.0 context. 展开更多
关键词 Cyber-physical systems discrete event systems fault diagnosis imperfect communication imperfect observation Industry 4.0 RESILIENCE
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Use of GIS and Remote Sensing Technology as a Decision Support Tool in Flood Disaster Management: The Case of Southeast Louisiana, USA 认领
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作者 Yaw A. Twumasi Edmund C. Merem +7 位作者 John B. Namwamba Ronald Okwemba Tomas Ayala-Silva Kamran Abdollahi Onyumbe E. Ben Lukongo Joshua Tate Kellyn La Cour-Conant Caroline O. Akinrinwoye 《地理信息系统(英文)》 2020年第2期141-157,共17页
The primary objective of this paper was to identify flood-prone areas in Southeast of Louisiana to help decision-makers to develop appropriate adaptation strategies and flood prediction, and mitigation of the effects ... The primary objective of this paper was to identify flood-prone areas in Southeast of Louisiana to help decision-makers to develop appropriate adaptation strategies and flood prediction, and mitigation of the effects on the community. In doing so, the paper uses satellite remote sensing and Geographic Information System (GIS) data for this purpose. Elevation data was obtained from the National Elevation Dataset (NED) produced by the United States Geological Survey (USGS) seamless data warehouse. Satellite data was also acquired from USGS Earth explorer website. Topographical information on runoff characteristics such as slope, aspect and the digital elevation model was generated. Grid interpolation TIN (triangulated irregular network) was carried from the digital elevation model (DEM) to create slope map. Image Drape was performed using ERDAS IMAGINE Virtual GIS. The output image was then draped over the NED elevation data for visualization purposes with vertical exaggeration of 16 feet. Results of the study revealed that majority of the study area lies in low-lying and very low-lying terrain below sea level. Policy recommendation in the form of the need to design and build a comprehensive Regional Information Systems (RIS) in the form of periodic inventorying, monitoring and evaluation with full support of the governments was made for the study area. 展开更多
关键词 GIS Remote Sensing FLOOD Disaster MANAGEMENT Regional Information Systems (RIS) SOUTHEAST LOUISIANA
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Post-Processing Time-Aware Optimal Scheduling of Single Robotic Cluster Tools 认领
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作者 Qing Hua Zhu Yan Qiao +1 位作者 NaiQi Wu Yan Hou 《自动化学报:英文版》 EI CSCD 2020年第2期597-605,共9页
Integrated circuit chips are produced on silicon wafers.Robotic cluster tools are widely used since they provide a reconfigurable and efficient environment for most wafer fabrication processes.Recent advances in new s... Integrated circuit chips are produced on silicon wafers.Robotic cluster tools are widely used since they provide a reconfigurable and efficient environment for most wafer fabrication processes.Recent advances in new semiconductor materials bring about new functionality for integrated circuits.After a wafer is processed in a processing chamber,the wafer should be removed from there as fast as possible to guarantee its high-quality integrated circuits.Meanwhile,maximization of the throughput of robotic cluster tools is desired.This work aims to perform post-processing time-aware scheduling for such tools subject to wafer residencytime constraints.To do so,closed-form expression algorithms are derived to compute robot waiting time accurately upon the analysis of particular events of robot waiting for singlearm cluster tools.Examples are given to show the application and effectiveness of the proposed algorithms. 展开更多
关键词 CLUSTER tool DISCRETE EVENT SYSTEMS optimization ROBOTIC SYSTEMS SCHEDULING
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The First-Order Comprehensive Sensitivity Analysis Methodology (1st-CASAM) for Scalar-Valued Responses: I. Theory 认领
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作者 Dan Gabriel Cacuci 《美国计算数学期刊(英文)》 2020年第2期275-289,共15页
This work presents the first-order comprehensive adjoint sensitivity analysis methodology (1st-CASAM) for computing efficiently, exactly, and exhaustively, the first-order sensitivities of scalar-valued responses (res... This work presents the first-order comprehensive adjoint sensitivity analysis methodology (1st-CASAM) for computing efficiently, exactly, and exhaustively, the first-order sensitivities of scalar-valued responses (results of interest) of coupled nonlinear physical systems characterized by imprecisely known model parameters, boundaries and interfaces between the coupled systems. The 1st-CASAM highlights the conclusion that response sensitivities to the imprecisely known domain boundaries and interfaces can arise both from the definition of the system’s response as well as from the equations, interfaces and boundary conditions defining the model and its imprecisely known domain. By enabling, in premiere, the exact computations of sensitivities to interface and boundary parameters and conditions, the 1st-CASAM enables the quantification of the effects of manufacturing tolerances on the responses of physical and engineering systems. Ongoing research will generalize the methodology presented in this work, aiming at computing exactly and efficiently higher-order response sensitivities for coupled systems involving imprecisely known interfaces, parameters, and boundaries. 展开更多
关键词 Adjoint Sensitivity Analysis (1st-CASAM) Response Sensitivities for Coupled Nonlinear Systems Imprecisely Known Interfaces Imprecisely Known Parameters Imprecisely Known Boundaries
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The First-Order Comprehensive Sensitivity Analysis Methodology (1<sup>st</sup>-CASAM) for Scalar-Valued Responses: II. Illustrative Application to a Heat Transport Benchmark Model 认领
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作者 Dan Gabriel Cacuci 《美国计算数学期刊(英文)》 2020年第2期290-310,共21页
This work illustrates the application of the 1<sup>st</sup>-CASAM to a paradigm heat transport model which admits exact closed-form solutions. The closed-form expressions obtained in this work for the sens... This work illustrates the application of the 1<sup>st</sup>-CASAM to a paradigm heat transport model which admits exact closed-form solutions. The closed-form expressions obtained in this work for the sensitivities of the temperature distributions within the model to the model’s parameters, internal interfaces and external boundaries can be used to benchmark commercial and production software packages for simulating heat transport. The 1<sup>st</sup>-CASAM highlights the novel finding that response sensitivities to the imprecisely known domain boundaries and interfaces can arise both from the definition of the system’s response as well as from the equations, interfaces and boundary conditions that characterize the model and its imprecisely known domain. By enabling, in premiere, the exact computations of sensitivities to interface and boundary parameters and conditions, the 1<sup>st</sup>-CASAM enables the quantification of the effects of manufacturing tolerances on the responses of physical and engineering systems. 展开更多
关键词 First-Order Comprehensive Adjoint Sensitivity Analysis Methodology (1st-CASAM) Response Sensitivities for Coupled Systems Involving Imprecisely Known Interfaces Parameters And Boundaries Coupled Heat Conduction and Convection
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A Historical Perspective on Development of Systems Engineering Discipline:A Review and Analysis 认领
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作者 Niamat Ullah Ibne Hossain Raed M.Jaradat +2 位作者 Michael A.Hamilton Charles B.Keating Simon R.Goerger 《Journal of Systems Science and Systems Engineering(系统科学与系统工程学报:英文版)》 SCIE EI CSCD 2020年第1期1-35,共35页
Since its inception,Systems Engineering(SE)has developed as a distinctive discipline,and there has been significant progress in this field in the past two decades.Compared to other engineering disciplines,SE is not af... Since its inception,Systems Engineering(SE)has developed as a distinctive discipline,and there has been significant progress in this field in the past two decades.Compared to other engineering disciplines,SE is not affirmed by a set of underlying fundamental propositions,instead it has emerged as a set of best practices to deal with intricacies stemming from the stochastic nature of engineering complex systems and addressing their problems.Since the existing methodologies and paradigms(dominant patterns of thought and concepts)of SE are very diverse and somewhat fragmented.This appears to create some confusion regarding the design,deployment,operation,and application of SE.The purpose of this paper is 1)to delineate the development of SE from 1926-2017 based on insights derived from a histogram analysis,2)to discuss the different paradigms and school of thoughts related to SE,3)to derive a set of fundamental attributes of SE using advanced coding techniques and analysis,and 4)to present a newly developed instrument that could assess the performance of systems engineers.More than Two hundred and fifty different sources have been reviewed in this research in order to demonstrate the development trajectory of the SE discipline based on the frequency of publication. 展开更多
关键词 SYSTEMS Engineering(SE) HISTORY DEVELOPMENT SYSTEMS ENGINEERING attributes performance measures
Life: A Huge Archive Electronic Archive Has Become an Urgent Necessity in the Face of Enormous Technological Advances 认领
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作者 Ahmed Yousef Laarfi 《电脑和通信(英文)》 2020年第4期1-10,共10页
Smart devices collaborate in increasing the quantity of information hugely. Therefore, traditional archiving couldn’t support this explosion of information. The electronic archive will lead to many advantages such as... Smart devices collaborate in increasing the quantity of information hugely. Therefore, traditional archiving couldn’t support this explosion of information. The electronic archive will lead to many advantages such as faster access, privacy and security, data accessibility, and distribution of authorities between administrative levels. This paper will discuss electronic archiving and whether it is a necessity or an administrative luxury. This research shed some light on three main topics, which are general archiving, distributed database systems, and a case study. 展开更多
关键词 ARCHIVING Distributed Database Systems INDEXING And Retrieving Data ELECTRONIC ARCHIVING
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