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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 29-34页

作者： LIU Kai LI Yi ji Hong WU Xu-guang School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Coordinated multi-point transmission/reception （CoMP） was proposed currently as an effective technology to improve cell-edge throughput in next-generation wireless systems. Most of the existing work discussed clustering methods mostly to maximize the edge user throughput while neglecting the problem of energy efficiency, such as those algorithm clustering base stations （BSs） of better channel condition and BSs of worse channel condition together. In addition, BSs usually increase the transmit power to achieve higher throughput without any considering of interference caused to other users, that may result in energy waste. The authors focus on the throughput maximizing problem while fully considering energy saving problem in CoMP systems. A coefficient is defined to describe the fitness of clusters. Then a sub-carrier allocation algorithm with clustering method is put forward for CoMP downlink, which can save the transmit power of BS and increase the throughput. Furthermore a power allocation scheme is proposed based on non-cooperation game; in which the transmit power is decreased by BSs generally to reach the Nash equation （NE）. Simulation shows that the proposed sub-carrier allocation scheme and power allocation algorithm are better than the existing ones on users＇ throughput while consumes much less energy.

关键词： CoMP energy saving game theory power allocation sub-carrier allocation

Investigation on microscopic invasion characteristics and retention mechanism of fracturing fluid in fractured porous media

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Petroleum Science 2022年第4期19卷 1745-1756页

作者： Qi-An Da Chuan-jin Yao Xue Zhang Xiao-pu Wang Xiao-Huan Qu guang-Lun Lei Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPeople's Republicof China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPeople's Republic of China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao266580ShandongPeople's Republic of China

Reservoir damage caused by guar gum fracturing fluid and slick water seriously affects the subsequent oil and gas production. However, the invasion characteristics and retention mechanisms of fracturing fluids in the fracture-matrix zone are still unclear. In this work, a microscopic model reflecting the characteristics of the fracture-matrix zone was designed. Based on the microfluidic experimental method, the process of fracturing fluid invasion, flowback and retention in the fracture-matrix zone was investigated visually and characterized quantitatively. The factors and mechanisms affecting fracturing fluid retention in the fracture-matrix zone were analyzed and clarified. The results indicated that in the invasion process, the frontal swept range of slick water was larger than that of the guar gum fracturing fluid, and the oil displacement efficiency and damage rate were lower than those of the guar gum fracturing fluid under the same invasion pressure. With the increase in invasion pressure, the damage rate of slick water increased from 61.09% to 82.77%, and that of the guar gum fracturing fluid decreased from 93.45% to83.36%. Before subsequent oil production, the invaded fracturing fluid was mainly concentrated in the medium-high permeability area of the fracture-matrix zone. The main resistance of slick water was capillary force, while that of the guar fracturing fluid was mainly viscous resistance. The fracturing fluid retention was most serious in the low permeability region and the region near the end of the *** experimental and numerical simulation results showed that increasing the production pressure difference could improve the velocity field distribution of the fracture-matrix zone, increase the flowback swept range and finally reduce the retention rate of the fracture fluid. The retention mechanisms of slick water in the fracture-matrix zone include emulsion retention and flow field retention, while those of the guar gum fracturing fluid inc

关键词： Microfluidic experiment Reservoir damage Fracturing fluid Fracture-matrix zone Retention mechanism

Joint use of time-domain and windowed method for design of modulated DFT filter banks

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 91-96页

作者： ZHUANG Ling ji Xiang SHAO Kai WANG guang-yu Chongqing Key Laboratory of Mobile Communications Technology Chongqing University of Posts and Telecommunications

A novel and efficient technique to design modulated discrete Fourier transform （DFT） filter banks is introduced in this paper. The proposed method first relaxes the limits that the synthesis filters are the time-reversed version of the analysis filters and then adopts the time domain formula of the perfect reconstruction property as the solution to design the synthesis filters. The prototype filter in analysis filter banks is designed based on Fourier-Kaiser window approach. Simulation results show that the designed filter banks approximately satisfy the perfect reconstruction with controllable reconstruction errors.

关键词： time-domain formula DFT filter banks prototype filter design filter banks design

基于原位交联增容策略的增强PLA/NR共混物界面相容性和发泡性能研究

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陕西科技大学学报 2025年第1期43卷 73-80,100页

作者：王广静邵亮苏晨阳马春燕姬占有陕西科技大学化学与化工学院中国轻工业轻化工助剂重点实验室陕西西安710021

聚乳酸(PLA)是目前最具发展潜力的生物材料之一,但其韧性差,极大的限制了在塑料领域的发展与应用.已有研究发现天然橡胶(NR)的引入可以改善其韧性差的缺陷,但二者为不相容体系,发泡性能差.因此,本文基于原位交联增容原理,采用1,4-双(叔... 详细信息

聚乳酸(PLA)是目前最具发展潜力的生物材料之一,但其韧性差,极大的限制了在塑料领域的发展与应用.已有研究发现天然橡胶(NR)的引入可以改善其韧性差的缺陷,但二者为不相容体系,发泡性能差.因此,本文基于原位交联增容原理,采用1,4-双(叔丁基过氧异丙基)苯(BIPB)增强PLA和NR的界面相容性,并以超临界二氧化碳(scCO_(2))发泡技术制备了PLA/NR复合发泡材料.探究了不同BIPB含量对复合材料界面相容性、韧性及复合材料发泡行为的影响.结果表明,BIPB的引入显著增强了PLA/NR复合材料的相容性、韧性及发泡性能.当BIPB含量为0.25 phr时,PLA/NR复合材料的断裂伸长率从原来的25.75%增加到35.24%,提升了1.37倍;表观密度从初始的0.565 g·cm^(-3)下降至0.373 g·cm^(-3);平均泡孔尺寸从7.5μm下降至5.0μm.

关键词：聚乳酸天然橡胶 1,4-双(叔丁基过氧异丙基)苯超临界发泡相容性

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Triple puncture for Primary Trigeminal Neuralgia:A Randomized Clinical Trial

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Current Medical Science 2019年第4期39卷 638-644页

作者： Yang-pu ZHANG Yan WANG Wen-guang XIA Ai-qun SONG Department of Physical Medicine and Rehabilitation Hubei Provincial Hospital of Integrated Chinese and Western MedicineWuhan 430015China Sector of P.E. China University of GeosciencesWuhan 430074China Hubei Provincial Hospital of Traditional Chinese Medicine Wuhan 430061China Hubei Province Academy of Traditional Chinese Medicine Wuhan 430074China

To evaluate the effect of triple puncture on primary trigeminal neuralgia (pTN),64 patients with pTN were randomly assigned to two groups:treatment group and control *** participants in the treatment group received triple puncture treatment of 6 times per week for 4 weeks,and those in control group were given carbamazepine (300-600 mg per day) for at least 1 *** and after treatment,the primary outcomes including the total efficiency rate and the VAS pain scores,and the secondary outcomes including the frequency of pain attack and adverse events were ***-two participants finished the study (33 in treatment group and 29 in control group individually).After treatment,the symptoms (mainly pain) of the two groups were *** total efficiency rate in the treatment group and control group was 90.9% and 75.9% *** VAS pain scores and frequency of pain attack were significantly reduced in the treatment group as compared with the control group (Ppuncture can effectively improve the quality of life of patients with pTN and has less side effects.

关键词： triple puncture primary trigeminal neuralgia randomized clinical trial

Remote Sensing Data Processing Process Scheduling Based on Reinforcement Learning in Cloud Environment

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 1965-1979页

作者： Ying Du Shuo Zhang pu Cheng Rita Yi Man Li Xiao-guang Yue School of Computer and Information Engineering Henan UniversityKaifeng475004China Henan Province Engineering Research Center of Spatial Information Processing Henan UniversityKaifeng475004China School of Software Henan UniversityKaifeng475004China Department of Economics and Finance/Sustainable Real Estate Research Center Hong Kong Shue Yan UniversityHong Kong999077China Department of Computer Science and Engineering European University CyprusNicosia1516Cyprus CIICESI-ESTG Politécnico do PortoFelgueiras4610-156Portugal

Task scheduling plays a crucial role in cloud computing and is a key factor determining cloud computing *** solve the task scheduling problem for remote sensing data processing in cloud computing,this paper proposes a workflow task scheduling algorithm—Workflow Task Scheduling Algorithm based on Deep Reinforcement Learning(WDRL).The remote sensing data process modeling is transformed into a directed acyclic graph scheduling ***,the algorithm is designed by establishing a Markov decision model and adopting a fitness calculation ***,combine the advantages of reinforcement learning and deep neural networks to minimize make-time for remote sensing data processes from *** experiment is based on the development of CloudSim and Python and compares the change of completion time in the process of remote sensing *** results showthat compared with several traditionalmeta-heuristic scheduling algorithms,WDRL can effectively achieve the goal of optimizing task scheduling efficiency.

关键词： Cloud computing reinforcement learning remote sensing task scheduling

Dependence of anomalous resistivity on bulk drift velocity of electrons in the reconnecting current sheets in solar flares

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Research in Astronomy and Astrophysics 2010年第11期10卷 1186-1194页

作者： Gui-Ping Wu guang-Li Huang Hai-Sheng ji Department of Physics Southeast University Nanjing 210096 China purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

Anomalous resistivity is critical for triggering fast magnetic reconnection in the nearly collisionless coronal plasma. Its nonlinear dependence on bulk drift velocity is usually assumed in MHD simulations. However, the mechanism for the production of anomalous resistivity and its evolution is still an open question. We numerically solved the one dimension Vlasov equation with the typical solar coronal parameters and realistic mass ratios to infer the relationship between anomalous resistivity and bulk drift velocity of electrons in the reconnecting current sheets as well as its non- linear characteristics. Our principal findings are summarized as follows： 1） the relationship between the anomalous resistivity and bulk drift velocity of electrons relative to ions may be described as ηmax=0.03724（vd/ve）^5.702Ωm for vd/ve in the range of 1.4-2.0 and ηmax=0.8746（vd/ve）^1.284Ωm for vd/ve in the range of 2.5-4.5;2）if drift velocity is just slightly larger than the threshold of ion-acoustic instability, the anomalous resistivity due to the wave-particle interactions is enhanced by about five orders as compared with classic resistivity due to Coulomb collisions, With the increase of drift velocity from 1.4ve to 4.5Ve, the anomalous resistivity continues to increase 100 times; 3） in the rise phase of unstable waves, the anomalous resistivity has the same order as the one estimated from quasi-linear theory; after saturation of unstable waves, the anomalous resistivity decreases at least about one order as com- pared with its peak value; 4） considering that the final velocity of electrons ejected out of the reconnecting current sheet （RCS） decreases with the distance from the neutral point in the neutral plane, the anomalous resistivity decreases with the distance from the neutral point, which is favorable for the Petschek-like reconnection to take place.

关键词： instabilities -- waves -- Sun: flares -- acceleration of particles

Nonorthogonal Tight-binding Study of the Geometries and Electronic Properties of Ge_n(n=2-20)Clusters

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Chemical Research in Chinese Universities 1999年第1期15卷 54-59页

作者： LI Si-dian ZHAO ji-jun WANG guang-hou Taiyuan TeachersCollege Taiyuan030001 Department of Physics and National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093

The universal parameter nonorthogonal tight binding scheme proposed by Menon and Subbaswamy was used to optimize the geometrical structures, binding energies and electron affinities of small germanium clusters Ge n ( n =2—20). A complete agreement with available ab initio results from the lowest energy structures for Ge 2—Ge 6 was obtained and reasonable structures for these clusters were predicted and compared with those of corresponding silicon clusters in the range of n =7—20 . The averaged discrepancy with experiments in binding energies for n =2—7 is about 6% and the calculated electron affinities agree well with the measured values in the range of n =2—8 as well.

关键词： Germanium cluster Tight binding study Geometry Electronic property

AdS/QCD and Applications of Light-Front Holography

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Communications in Theoretical Physics 2012年第4期57卷 641-664页

作者： Stanley J.Brodsky Guy F.de Téramond CAO pu-guang SLAC National Accelerator Laboratory Stanford University Stanford CA 94309 USA and CPa-Origins Southern Denmark University Odense Denmark Massey University Palmerston North New Zealand Universidad de Costa Rica San Jose Costa Rica

Light-front holography leads to a rigorous connection between hadronic amplitudes in a higher dimensional anti-de Sitter(AdS) space and frame-independent light-front wavefunctions of hadrons in(3 + 1)-dimensional physical space-time,thus providing a compelling physical interpretation of the AdS/CFT correspondence principle and AdS/QCD,a useful framework which describes the correspondence between theories in a modified AdS 5 background and confining field theories in physical *** a first semiclassical approximation,where quantum loops and quark masses are not included,this approach leads to a single-variable light-front Schro¨dinger equation which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular *** coordinate z in AdS space is uniquely identified with a Lorentz-invariant coordinate ζ which measures the separation of the constituents within a hadron at equal light-front *** internal structure of hadrons is explicitly introduced and the angular momentum of the constituents plays a key *** give an overview of the light-front holographic approach to strongly coupled *** particular,we study the photon-to-meson transition form factors(TFFs) FMγ(Q 2) for γ→ M using light-front holographic *** results for the TFFs for the η and η ' mesons are also *** novel features of QCD are discussed,including the consequences of confinement for quark and gluon condensates.A method for computing the hadronization of quark and gluon jets at the amplitude level is outlined.

关键词： gauge/gravity correspondence light-front dynamics strongly coupled QCD meson and baryon spectrum meson and nucleon form factors

A flexible architecture for job management in a grid environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 95-105页

作者： LUAN Cui-ju SONG guang-hua ZHENG Yao ZHANG ji-fa College of Information Engineering Shanghai Maritime University Shanghai 200135 China School of Computer Science and Center for Engineering and Scientific Computation Zhejiang University Hangzhou 310027 China

Job management is a key issue in computational grids, and normally involves job definition, scheduling, executing and monitoring. However, job management in the existing grid middleware needs to be improved in terms of efficiency and flexibility. This paper addresses a flexible architecture for job management with detailed design and implementation. Frameworks for job scheduling and monitoring, as two important aspects, are also presented. The proposed job management has the advantages of reusability of job definition, flexible and automatic file operation, visual steering of file transfer and job execution, and adaptive application job scheduler. A job management wizard is designed to implement each step. Therefore, what the grid user needs to do is only to define the job by constructing necessary information at runtime. In addition, the job space is adopted to ensure the security of the job management. Experimental results showed that this approach is user-friendly and system efficient.

关键词： Grid Job management Job definition reuse Steering of job transfer Job space