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Influence of Wave Direction on the Dynamic Response of A Submarine Equipment Launch and Recovery System

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China Ocean Engineering 2022年第1期36卷 144-154页

作者： JIN Yong-ping XIE Kun LIU Guang-ping WAN Bu-yan PENG you-duo National-Local Joint Engineering Laboratory of Marine Mineral Resources Exploration Equipment and Safety Technology Hunan University of Science and TechnologyXiangtan 411201China

A launch and recovery system for a seafloor drill was studied using a dynamic model that considered the influences of seawater resistance and the elastic deformation of the cable based on the lumped mass *** influence of wave direction angle on heave,roll,and pitch motions of the ship was analyzed,and those motion characteristics were then used to assess the tension response of the armored umbilical cable at the lifting point under different wave direction *** analyzing the different wave direction angles we found that,when a ship experiences longitudinal waves it will express longitudinal *** a ship encounters transverse waves,it will have transverse *** oblique waves from bow or stern,a ship will have both longitudinal and transverse movement,exhibiting obvious heave and pitch *** waves,in this study,produced the most obvious impact on armored umbilical cable ***,the tension of the armored umbilical cable will change based on the weight of the armored umbilical cable and the seafloor drill in the *** analysis has provided a useful reference for the study of heave compensation and the constant tension automatic control.

关键词： seafloor drill elastic cable lumped mass method motion characteristics analysis

Computation of an Emptiable Minimal Siphon in a Subclass of Petri Nets Using Mixed-Integer Programming

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 219-226页

作者： Shouguang Wang Wenli duo Xin Guo Xiaoning Jiang Dan you Kamel Barkaoui MengChu Zhou the School of Information and Electronic Engineering Zhejiang Gongshang UniversityHangzhou 310018China the Macao Institute of Systems Engineering Macao University of Science and TechnologyMacao 999078China the Department of Computer Science Conservatoire National des Arts et MétiersParis 75141France the Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewarkNJ 07102 USA the Institute of Systems Engineering and Collaborative Laboratory for Intelligent Science and Systems Macao University of Science and TechnologyMacao 999078China

Deadlock resolution strategies based on siphon control are widely *** computational efficiency largely depends on siphon ***-integer programming(MIP)can be utilized for the computation of an emptiable siphon in a Petri net(PN).Based on it,deadlock resolution strategies can be designed without requiring complete siphon enumeration that has exponential *** to this reason,various MIP methods are proposed for various subclasses of *** work proposes an innovative MIP method to compute an emptiable minimal siphon(EMS)for a subclass of PNs named S^(4)*** particular,many particular structural characteristics of EMS in S4 PR are formalized as constraints,which greatly reduces the solution *** results show that the proposed MIP method has higher computational ***,the proposed method allows one to determine the liveness of an ordinary S^(4)PR.

关键词： Automated manufacturing systems deadlocks discrete event system mixed-integer programming(MIP) Petri nets(PN) siphons

Speculation of fluid dynamics equations based on Liutex theory and constitutive relation of symmetric shearing deformation

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Journal of Hydrodynamics 2023年第4期35卷 607-629页

作者： Shuai-chen Zhu duo Wang yang Liu Hongyi Xu Department of Aeronautics and Astronautics Fudan UniversityShanghai200433China

The fluid kinematics of Liutex decomposes a velocity gradient tensor(VGT)of∇v into four components,including rotation(R),stretching/compressing(SC),anti-symmetric shear(Santi-sym)and symmetric shear(Ssym),as oppose to the traditional Cauchy-Stokes decomposition where a VGT was decomposed into the strain rate and vorticity *** current study limpidly clarified the physical meanings of these deformations in the newly-proposed decomposition from the perspectives of both fluid kinematics and *** in-depth understanding the physical connotations of these deformations,the present study further suggests that the Ssym be the only deformation appropriately correlated to the stress tensor,leading to the establishment of a new constitutive relation for Newtonian fluids with the modified model assumptions originated from Stokes in ***,the present research finds that the“principal decomposition”proposed by Liu is not mathematically unique when a VGT has three real eigenvalues(TR).Within the context,a new decomposition method is introduced to avoid the non-uniqueness issue arising from using the principal decomposition to establish fluid dynamics *** on the modified Stokes assumptions and the novel VGT decomposition method,a set of new fluid dynamics momentum equations are obtained for Newtonian *** added stress tensor of Fadd is identified as the key difference between the newly-derived governing equations and the conventional Navier-Stokes(N-S)equations,which is caused by excluding the SC correlation to the stress tensor in the new constitutive ***,a preliminary analysis of Fadd is conducted using the existing channel turbulence direct numerical simulations(DNS)data based on the traditional N-S *** Fadd is found widely existing in turbulence and is of the same order of magnitude with the other force ***,the Fadd is expected to have some nonnegligible effects on altering the current DNS data based on

关键词： Constitutive relation Liutex principal decomposition Newtonian fluid Navier-Stokes equations fluid kinematics fluid dynamics

Sediment settlement rate and consolidation time of flling reclamation in coal mining subsidence land

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International Journal of Coal Science & Technology 2022年第3期9卷 232-246页

作者： Linghua duo Zhenqi Hu Kun yang Yanan Li Faculty of Geomatics East China University of TechnologyNanchang 30013China School of Environment and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Institute of Land Reclamation and Ecological Restoration China University of Mining and Technology(Beijing)D11 Xueyuan RoadHaidian DistrictBeijing 100083China

With the continuous growth of the population and the continuous reduction of cultivated land,China’s food security is greatly *** addition,China’s coal mining has been mainly underground mining,causing land subsidence and damaging existing cultivated *** efect intensifes the contradiction between the growth of the risk population and the reduction of cultivated *** reclamation of mining subsidence land with Yellow River sediment is often used as an efective way to improve the recovery rate of cultivated *** the reclamation time and realizing continuous flling are signifcant *** work presented in this paper studied the sediment settlement rate and consolidation time by combining theory,feld flling and reclamation tests and numerical simulations.A feld flling test study was carried out in the lowlands of Jibeiwang Village,Qihe County,Shandong Province,*** calculating the drainage consolidation time,the consolidation factor of 0.015656 m^(2)/d,and the time factor for sediment consolidation of 0.575 were *** sediment consolidation time for this test was 9.18 *** calculation of sediment deposition rate and consolidation time is of great practical signifcance to guide the Yellow River sediment flling,realize continuous flling,and save reclamation time and cost.

关键词： Yellow River sediment Mining subsidence land Filling reclamation Consolidation time

Recent advances in energy storage mechanism of aqueous zinc-ion batteries

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Journal of Energy Chemistry 2021年第3期30卷 712-726页

作者： duo Chen Mengjie Lu Dong Cai Hang yang Wei Han Sino-Russian International Joint Laboratory for Clean Energy and Energy Conversion Technology College of PhysicsJilin UniversityChangchun 130012JilinChina International Center of Future Science Jilin UniversityChangchun 130012JilinChina

Aqueous rechargeable zinc-ion batteries(ZIBs)have recently attracted increasing research interest due to their unparalleled safety,fantastic cost competitiveness and promising capacity advantages compared with the commercial lithium ion ***,the disputed energy storage mechanism has been a confusing issue restraining the development of *** a lot of efforts have been dedicated to the exploration in battery chemistry,a comprehensive review that focuses on summarizing the energy storage mechanisms of ZIBs is ***,the energy storage mechanisms of aqueous rechargeable ZIBs are systematically reviewed in detail and summarized as four types,which are traditional Zn^(2+)insertion chemistry,dual ions co-insertion,chemical conversion reaction and coordination reaction of Zn^(2+)with organic ***,the promising exploration directions and rational prospects are also proposed in this review.

关键词： Zinc-ion batteries Energy storage mechanism Rechargeable aqueous battery Zn-MnO_(2)battery Electrolytic battery

Different Outcome of Myeloid Sarcoma with Spinal Cord Compression Preceding Acute Myeloid Leukemia:Report of Two Cases and Review of Literatures

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Chinese Journal of Cancer Research 2010年第2期22卷 156-162页

作者： Qiang Yin yang-yang Zhou duo Chen Wen-liang Li Key Laboratory of Cancer Prevention and Therapy Department of Neurosurgery and Neuro-oncology Tianjin Medical University Cancer Hospital Tianjin 300060 China Department of Neurosurgery Shengjing Hospital Affiliated to China Medical University Shenyang China

Myeloid sarcomas （MS） preceding acute myeloid leukemia （AML） are rare, which presenting as acute spinal cord compression is even rare. Here we report two new cases of myeloid sarcoma patients, whose outcomes were different. Twenty-seven patients with spinal MS preceding AML have been reported to date, including the two cases presented in this article. Surgical decompression was performed in 25 of the 27 patients, and 23 of these received additional anti-AML therapy. Considering our patients and the published cases in the literature we suggest that immunohistochemical study plays an essential role in arriving at a correct diagnosis of MS, and that emergency surgery to resect spinal MS is an available treatment to make neural function recovery, and that the disease must be treated with intensive chemotherapy similar to that used to treat AML as soon as possible after resection or irradiation of the tumor.

关键词： Spine Myeloid sarcoma Immunhistochemistry Acute myeloid leukemia

Metal Spray Forming Process Examined Using Mathematical Model

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Journal of Iron and Steel Research International 2008年第2期15卷 46-50页

作者： ZHANG Yin HE you-duo FAN Jun-fei REN San-bin School of Rare Earth Inner Mongolia University of Science and Technology Baotou 014010 Nei Monggol China Baoshan Iron and Steel Co Ltd Research Institute Shanghai 201900 China

The metal spray forming process was examined using the mathematical model simulation by Baosteel＇s test and developed *** mathematical model comprised of the probability and statistical analysis of the droplet mass b... 详细信息

关键词： spray forming droplet mathematical model billet

Train model acceleration and deceleration

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Science China Technological Sciences 2013年第3期56卷 642-647页

作者： yang QianSuo SONG JunHao LI duo ZHANG Jie yang GuoWei State Key Laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of Sciences

In order to accelerate a heavy train model with great dimensions to a speed higher than 300 km h?1 in a moving train model testing system,compressed air is utilized to drive the train model *** gas from an air gun pushes the piston in an accelerating tube *** piston is connected to the trailer through a rope,and the trailer pulls the train model to the desired *** the testing section,the train model enters the deceleration *** speed of the train model gradually decreases because of the braking force of the magnetic braking device on the bottom of the train model and the steel plates fixed on the floor of this *** dissipation of kinetic energy of the trailer is also based on a similar *** feasibility of these methods has been examined in a 180 m-long moving train model testing *** speed of the trailer alone reaches up to 490 km ***,a 34.8 kg model accelerates up to 350 km h?1;the smooth and safe stopping of the model is also possible.

关键词： moving train model acceleration deceleration magnetic braking air gun compressed air

A new barycenter code discriminator for multi-access interference

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Science China(Information Sciences) 2014年第2期57卷 113-121页

作者： WANG YongQing LI Cong XU duo yang Na School of Information and Electronics Beijing Institute of Technology

The performance of code tracking loop in direct sequence spread spectrum system decreases because of multi-access *** order to solve this problem,this paper presents a new code discriminator based on barycenter *** calculating the barycenter of code phase by multiple PN code branches’correlation results,PN code phase error can be *** analysis of new discriminator’s performance is given,and it is indicated that the code tracking loop using this algorithm can also solve the problems of low ranging precision and large mean deviation caused by multi-access *** efciency of the proposed algorithm is verified by simulation and measurements and the new discriminator is used in an aerospace engineering project successfully.

关键词： direct sequence spread spectrum code tracking loop code discriminator barycenter tracking