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Seru Scheduling Problems with Multiple Due-Windows Assignment and Learning Effect

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Journal of Systems Science and Systems Engineering 2022年第4期31卷 480-511页

作者： Yujing Jiang Zhe Zhang Xiaoling song yong Yin School of Economics and Management Nanjing University of Science and TechnologyNanjing210094P.R.China Graduate School of Business Doshisha UniversityKarasuma-ImadegawaKamigyo-kuKyoto602-8580Japan

This paper deals with seru scheduling problems with multiple due windows assignment and DeJong’s learning *** time intervals are assigned to jobs with multiple due windows and learning effect is introduced to characterize the decrease of processing times with the accumulation of the working *** assume that the set of jobs assigned to each due window is independent,and no inclusion exists between due *** objective is to determine the optimal due window positions and sizes,the set of jobs assigned to each due window,and the optimal schedule in each seru to minimize a multidimensional function,which consists of the earliness and tardiness punishment cost,as well as the due window related starting time and size *** find that when the number of jobs and the due windows assigned to each seru are pre-specified in advance,the problem can be solved in polynomial ***,the impacts of the due-window allocation strategy and learning effect on the total cost are respectively discussed based on numerical examples and special *** results show that if each seru is assigned with the same number of due windows,the total cost can be reduced with the increasing ratio of the due-window number to the to-be-processed job ***,with an increasing learning effect,the total cost will be decreased.

关键词： Scheduling seru production system due windows learning effect

Nonlinear Numerical Analysis of Vortex-Induced Vibration of A Three-Dimensional Deepwater Steep Wave Riser with Large Deformation Features

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China Ocean Engineering 2022年第4期36卷 601-613页

作者： CHENG yong song Fu-kai LI Ming-xin School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The cross-flow(CF)vortex-induced vibration(VIV)of a deepwater steep wave riser(SWR)subjected to uniform or shear flow loads is investigated *** model is based on a three-dimensional(3D)nonlinear elastic rod theory coupled with a wake oscillator *** this numerical simulation,the nonlinear motion equations of the riser with large deformation features are established in a global coordinate system to avoid the transformation between global and local coordinate systems,and are discretized with the time-domain finite element method(FEM).A wakeoscillator model is employed to study the vortex shedding,and the lift force generated by the wake flow is described in a van der Pol equation.A Newmark-βiterative scheme is used to solve their coupling equation for the VIV response of the *** developed model is validated against the existing experimental results for the VIV response of the top-tension riser(TTR).Then,the numerical simulations are executed to determine VIV characteristics of the *** effects of both flow velocity and the spanwise length of the flow field on the drag coefficient in the inline(IL)direction and the lift coefficient in the CF direction are investigated *** results indicate that compared with TTR,the low frequency and multi-modal vibration are the main components of the SWR due to the large deformation and flexible *** shear flow,the multi-frequency resonance dominates the VIV response of the SWR,especially at the hang-off segment.

关键词： steep wave riser vortex-induced vibration time domain simulation nonlinear finite element wake oscillator

Convergence of Broadband and Broadcast/Multicast in Maritime Information Networks

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Tsinghua Science and Technology 2021年第5期26卷 592-607页

作者： Jun Du Jian song yong Ren Jintao Wang the Department of Electronic Engineering Tsinghua UniversityBeijing 100084China the Institute for Ocean Engineering Tsinghua UniversityBeijing 100084 Peng Cheng Laboratory Shenzhen 518055China the Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084 the Key Laboratory of Digital TV System of Guangdong Province and Shenzhen City Research Institute of Tsinghua UniversityShenzhen 518057China

Recently,the fifth-generation(5G)of wireless networks mainly focuses on the terrestrial ***,the well-developed emerging technologies in 5G are hardly applied to the maritime communications,resulting from the lack of communication infrastructure deployed on the vast ocean,as well as different characteristics of wireless propagation environment over the sea and maritime user *** satisfy the expected plethora of broadband communications and multimedia applications on the ocean,a brand-new maritime information network with a comprehensive coverage capacity in terms of all-hour,all-weather,and all-sea-area has been expected as a revolutionary paradigm to extend the terrestrial capacity of enhanced broadband,massive access,ultra-reliable,and low-latency to the vast *** considering the limited available resource of maritime communication infrastructure,the convergence of broadband and broadcast/multicast can be regarded as a possible yet practical solution for realizing an efficient and flexible resource configuration with high quality of ***,according to such multi-functionality and all-coverage maritime information network,the monitoring and sensing of vast ocean area relying on massive Ocean of Things and advanced radar techniques can be also *** these issues above,this study proposes a Software Defined Networking(SDN)based Maritime Giant Cellular Network(MagicNet)architecture for broadband and multimedia *** on this network,the convergence techniques of broadband and broadcast/multicast,and their supporting for maritime monitoring and marine sensing are also introduced and surveyed.

关键词： Maritime Giant Cel ular Network(Magic Net) integrated broadcast-multicast-unicast communications maritime multimedia services Ocean of Things(OoT) al-coverage

Formation and Relative Stabilities of Core-Shelled L12-Phase Nano-structures in Dilute Al–Sc–Er Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1627-1634页

作者： Chaomin Zhangi yong Jiang Xiuhua Guo Kexing song School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023People's Republic of China School of Materials Science and Engineering Central South UniversityChangsha 410083China Henan Province Key Laboratory of Nonferrous Metal Material Science and Processing Technology Luoyang 471023People's Republic of China Collaborative Innovation Center of Nonferrous Metals Luoyang 471023Henan ProvinceChina Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology Luoyang 471023Henan ProvincePeople's Republic of China

First-principles thermodynamic calculations were carried out at the interface level for understanding the precipitation of coherent L12-phase nano-structures in dilute Al–Sc–Er *** energetics,relevant to bulk substitution,interface formation,interfacial coherent strain and segregation,were calculated and used to evaluate the nucleation and relative stabilities of various possible L12 *** matrix-dissolved solute Er(or Sc)can substitute Sc(or Er)in L12-Al3Sc(or Al3Er).The inter-substitution between L12-Al3Sc and Al3Er is not energy *** L12-Al3(Er x Sc 1.x)precipitates tend to form the Al3Er-core and Al3Sc-shell structure with a sharp core/shell *** possible formation mechanisms were proposed and *** eff ects of Er/Sc ratio and aging temperature on the relative stabilities of L12-phase nanostructures in Al were also discussed.

关键词： Al–Sc–Er alloy L12 phase Core-shell Interface First-principles

Coverless Steganography for Digital Images Based on a Generative Model

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Computers, Materials & Continua 2018年第6期55卷 483-493页

作者： Xintao duan Haoxian song Chuan Qin Muhammad Khurram Khan Henan Normal University XinxiangHenan 453007China University of Shanghai for Science and Technology Shanghai 200093China Center of Excellence in Information Assurance(CoEIA) King Saud UniversityRiyadhSaudi Arabia

In this paper,we propose a novel coverless image steganographic scheme based on a generative *** our scheme,the secret image is first fed to the generative model database,to generate a meaning-normal and independent image different from the secret *** generated image is then transmitted to the receiver and fed to the generative model database to generate another image visually the same as the secret ***,we only need to transmit the meaning-normal image which is not related to the secret image,and we can achieve the same effect as the transmission of the secret *** is the first time to propose the coverless image information steganographic scheme based on generative model,compared with the traditional image *** transmitted image is not embedded with any information of the secret image in this method,therefore,can effectively resist steganalysis *** results show that our scheme has high capacity,security and reliability.

关键词： Generative model coverless image steganography steganalysis steganographic capacity security.

Autonomous mission reconstruction during the ascending flight of launch vehicles under typical propulsion system failures

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Chinese Journal of Aeronautics 2022年第6期35卷 211-225页

作者： Zhengyu song Yin LIU yong HE Cong WANG China Academy of Launch Vehicle Technology Beijing 100076China Beijing Institute of Astronautical Systems Engineering Beijing 100076China Beijing Aerospace Automatic Control Institute Beijing 100854China

In recent years, Chinese Long March(LM) launchers have experienced several launch failures, most of which occurred in their propulsion systems, and this paper studies Autonomous Mission Reconstruction(AMRC) technology to alleviate losses due to these failures. The status of the techniques related to AMRC, including trajectory and mission planning, guidance methods,and fault tolerant technologies, are reviewed, and their features are compared, which reflect the challenges faced by AMRC technology. After a brief introduction about the failure modes of engines that can occur during flight, and the fundamentals of trajectory planning and joint optimization of the target orbit and flight path, an AMRC algorithm is proposed for geostationary transfer orbit launch missions. The algorithm evaluates the residual performance onboard, and plans new objectives and corresponding flight path by iterative guidance mode or segmented state triggered optimization methods in real-time. Three failure scenarios that have occurred during previous LM missions are simulated to check the robustness of the algorithm: imminent explosion risk of the boosters’ engines, thrust drop during the first stage of flight, and being unable to start the engine during the second stage. The payloads would fall from space according to the current design under these conditions, but they were saved with the AMRC algorithm in the simulations, which allowed the rocket to get into the target orbit as intended or the payloads were deployed in other orbits without crashing. Although spaceflight can be very unforgiving, the AMRC algorithm has the potential to avoid the total loss of a launch mission when faced with these kinds of typical failures.

关键词： Autonomous mission reconstruction Closed-loop guidance State triggered indices Rescue orbits Launch vehicles

Coordination states of metal ions in molten salts and their characterization methods

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1261-1277页

作者： Xin song Shaolong Li Shanshan Liu yong Fan Jilin He Jianxun song School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals Laboratory Zhengzhou UniversityZhengzhou 450001China College of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China

The macroscopic characteristics of molten salts are governed by their *** on the structures of molten salts provides the foundation for a full understanding of the physicochemical properties of molten salts as well as a deeper analysis of the microscopic electrolysis process in molten *** about the microstructure of matter can be obtained with the help of several speculative and experimental *** this review,the advantages and disadvantages of the various test procedures used to determine the microstructures of molten salts are *** typical coordination configurations of metal ions in molten salt systems are also ***,the impact of temperature,anions,cations,and metal oxides(O2-)on the structures of molten salts is discussed in *** accuracy and completeness of the information on molten salt structures need to be investigated by the integration of multiple methods and interdisciplinary *** on the microstructure and coordination of molten salts deepens the understanding of the elementary elements of the microstructure of *** paper,which is based on the review of the coordination states of metal ions in molten salts,is hoped to inspire researchers to explore the inter-relationship between the microstructure and macroscopic properties of materials.

关键词： microstructure salts coordination

Performance Analysis of the Effects of Microgrooved Surface on A Marine Current Turbine with Underwater Mooring Platform

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China Ocean Engineering 2022年第5期36卷 755-766页

作者： DANG Zhi-gao MAO Zhao-yong song Bao-wei YANG Guang-yong School of New Energy Nanjing University of Science and TechnologyJiangyin 214443China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory for Unmanned Underwater Vehicle Northwestern Polytechnical UniversityXi’an 710072China Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China

Marine current turbine(MCT),which is designed for the power supply of underwater mooring platform(UMP),is investigated in this *** reduce its flow noise,the microgrooved surface is applied at the suction surface of the turbine *** analyses of the effects of the UMP on MCT with microgrooved surface in different working conditions are *** transient turbulent flow field is obtained by incompressible large eddy simulation(LES),and then the Ffowcs Williams and Hawkings(FW-H)acoustic analogy is adopted to forecast the flow noise generated from the pressure fluctuations and loadings of the UMP shell and MCT blade *** numerical methods are first validated with experimental data and good agreements are ***,the influence of several key parameters on the performance of the MCT is then systematically studied,including interval distance,angle of pitch and angle of *** each case,the hydrodynamic parameters(thrust coefficient,torque coefficient and power coefficient),the vortical structures behind the model and the overall sound pressure level(OASPL)directionality are ***,the noise reduction effect of the microgrooved surface is also *** present investigation could provide an overall understanding for the performance of MCT combined with UMP.

关键词： marine current turbine underwater mooring platform microgrooved surface large eddy simulation flow noise

Reductive recovery of manganese from low-grade manganese dioxide ore using toxic nitrocellulose acid wastewater as reductant

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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 990-999页

作者： yong-tao Zhang Zhi-gang Dan Ning duan Bao-ping Xin School of Petroleum and Environment Engineering Yan'an University School of Materials Science & Engineering Beijing Institute of Technology Technology Center for Heavy Metal Cleaner Production Engineering Chinese Research Academy of Environmental Sciences

The hydrometallurgical strategy of extracting Mn from low-grade Mn ores has attracted attention for the production of electrolytic manganese metal(EMM). In this work, the reductive dissolution of low-grade Mn O2 ores using toxic nitrocellulose acidic wastewater(NAW) as a reductant was investigated for the first time. Under the optimized conditions of an Mn O2 ore dosage of 100 g·L-1, an ore particle size of-200 mesh, concentrated H2 SO4-to-NAW volume ratio of 0.12, reaction temperature of 90°C, stirring speed at 160 r·min-1, and a contact time of 120 min, the reductive leaching efficiency of Mn and the total organic carbon(TOC) removal efficiency of NAW reached 97.4% and 98.5%, respectively. The residual TOC of 31.6 mg·L-1 did not adversely affect the preparation of EMM. The current process offers a feasible route for the concurrent realization of the reductive leaching of Mn and the treatment of toxic wastewater via a simple one-step process.

关键词： low-grade manganese dioxide ore nitrocellulose acid wastewater sulfuric acid leaching Mn reductive dissolution electrolytic manganese metal