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energy Efficient Constrained Shortest Path First-Based Joint Resource Allocation and Route Selection for Multi-Hop CRNs

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China Communications 2017年第12期14卷 72-86页

作者： Qianbin Chen Ling Wang Yuanpeng Gao Rong Chai Xiaoge Huang Key Lab of Mobile Communication Technology Chongqing University of Posts and Telecommunications Chongqing 400065 China

Cognitive radio networks(CRNs) are expected to improve spectrum utilization efficiently by allowing secondary users(SUs) to opportunistically access the licensed spectrum of primary users(PUs).In CRNs,source and destination SUs may achieve information interaction in an ad hoc *** the case that no direct transmission link between the SU transmission pairs is available,multi-hop relay SUs can be applied to forward information for the source and destination SUs,resulting in multi-hop *** this paper,we consider a multi-hop CRN consisting of multiple PUs,SU transmission pairs and relay *** the importance of transmission hops and the tradeoff between data rate and power consumption,we propose an energy efficient constrained shortest path first(CSPF)-based joint resource allocation and route selection algorithm,which consists of two sub-algorithms,i.e.,CSPF-based route selection sub-algorithm and energy efficient resource allocation *** specifically,we first apply CSPF-based route selection sub-algorithm to obtain the shortest candidate routes(SCRs) between the SU pair under the transmission ***,an energy efficient resource allocation problem of the SCRs is formulated and solved by applying iterative algorithm and Lagrange dual ***-lation results demonstrate the effectiveness of the proposed algorithm.

关键词： cognitive radio network multi-hop relay resource allocation route selection energy efficiency

energy analysis for damage and catastrophic failure of rocks

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Science China(Technological Sciences) 2011年第S1期54卷 199-209页

作者： XIE HePing 1,2,LI LiYun 2,1,JU Yang 2,PENG RuiDong 2 & YANG YongMing 2 1 Sichuan University,Chengdu 610065,China 2 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China Sichuan University Chengdu China State Key Laboratory of Coal Resources and Safe Mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete China University of Mining and Technology Beijing China

The development history and current state of studies on the characteristics and mechanisms of deformation and failure of rock materials were briefly reviewed from the viewpoint of *** main scope and the achievable objectives of the energy-based research system were *** was validated by experiments that the damage process of rocks can be well described by the rock damage evolution equation established based on energy *** was found from the uniaxial compression and biaxial compression tests that only a small proportion of the total input energy in hard rocks is dissipated before peak load and a large proportion in soft rocks is dissipated before peak *** both hard and soft rocks,the energy dissipated after peak load accounts for a greater *** energy would be required for rock failure under equal biaxial compression than under unequal biaxial *** total absorbed energy is different for rock failure under high-rate loading and low-rate *** fragmented failure pattern usually corresponds to higher energy *** mesoscopic analysis on the damage and failure of bedded salt rocks showed that the energy dissipation is prominent and the total absorbed energy for rock failure is low when cracks propagate in the weak mud interlayer while it is contrary when cracks propagate in the salt *** energy accumulation,transfer,dissipation and release during the failure process of tunnel with impending failure under disturbance were analyzed theoretically based on the elastoplastic mechanics ***,the spatial distribution of energy dissipation and energy release of fractured rocks under unloading was simulated *** was demonstrated that energy is likely to be released from the weakest surface under compression,which triggers the global failure of rocks.

关键词： rock deformation failure energy accumulation energy dissipation energy release

energy distributions of the large-scale horizontal currents caused by wind in the baroclinic ocean

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Science China Earth Sciences 2005年第12期48卷 2267-2275页

作者： ZHOU Lei1, TIAN Jiwei1 & WANG Dongxiao2 1. Physical Oceanography Laboratory, Ocean University of China, Qingdao 266003, China 2. Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangdong 510301, China Physical Oceanography Laboratory Ocean University of China Qingdao China Key Laboratory of Tropical Marine Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangdong China

Ocean current data for nearly 3 months in the South China Sea (SCS), combined with the NCEP/NCAR reanalysis wind data, are analyzed. The results indicate that the wind en-ergy enters the upper mixed layer in a wide continuous frequency band. In addition, the interac-tion between the low-frequency wind anomaly and the low-frequency current anomaly is the most ‘effective’ way for the energy input from the wind to the upper ocean. However, only the inertial and the near inertial energy propagate downwards through the upper mixed layer. The down-ward-propagating energy is distributed into the barotropic currents, the baroclinic currents and each mode of the baroclinic currents following the normal distributions. The energy change ratios between the barotropic motion to the baroclinic motion induced by the wind present a normal distribution of N (0.0242, 0.3947). The energy change ratios of the first 4 baroclinic modes to the whole baroclinic currents also follow the normal distributions. The first baroclinic mode follows N (0.2628, 0.1872), the second N (0.1979, 0.1504), the third N (0.1331, 0.1633), and the fourth N (0.0650, 0.1540), respectively.

关键词： wind anomaly, ocean current anomaly, energy transportation, wide frequency band, near-inertial fre-quency, energy distribution.

energy Efficient MAC Protocol for Wireless Full-Duplex Networks

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China Communications 2018年第1期15卷 35-44页

作者： Yu Song Wangdong Qi Wenchi Cheng Army Engineering University Nanjing 210007 China National University of Defense Technology Xi'an 710106 China State key Laboratory Services Networks Xidian University Xi'an 710048 China

The wireless full-duplex(FD) nodes can transmit and receive at the same time using the same frequency-band. Currently, the latest FD media access control(MAC) protocols mainly focus on how to convert the physical layer gains of FD nodes to the throughput gain of wireless FD networks, but pay little attention to the energy consumptions of FD nodes. In this paper, we propose an energy efficient FD MAC protocol. According to the values of self-interference cancellation coefficients corresponding to the nodes of each FD pair and the signal propagation attenuation, the proposed protocol can adaptively select the communication mode of the FD pair between the full-duplex and half-duplex. Also, the minimum transmit power for FD nodes can be obtained to achieve high energy efficiency. We develop an analytical model to characterize the performance of our protocol. The numerical results show that the proposed MAC protocol can optimize the system throughput and reduce the transmission energy consumptions of nodes simultaneously as compared with those of the existing works.

关键词： wireless full-duplex networks MAC protocol energy efficient self-interfer-ence cancellation coeff^cient

energy Release Rates for Interface Cracks in Multilayered Structures

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Computer Modeling in Engineering & Sciences 2019年第8期120卷 261-272页

作者： Changwei Huang Philip A.Williams Department of Civil Engineering Chung Yuan Christian UniversityTaoyuan 32023Taiwan Simutech Solution Corporation 14FNo.90Section 2Nanjing E.Rd.Taipei 10406Taiwan

This paper examines the evolution of the interfacial deflection energy release rates in multilayered structures under four-point *** J-integral and the extended finite element method(XFEM)are adopted to investigate the evolution of the interfacial deflection energy release rates of composite *** results not only verify the accuracy of analytical solutions for the steady-state interfacial deflection energy release rate,but also provide the evolutionary history of the interfacial deflection energy release rate under different crack *** addition,non-dimensional parametric analyses are performed to discuss the effects of normalized ratios of the crack length,the elastic modulus,and the thickness on the interfacial deflection energy release *** results demonstrate that the elastic modulus ratio and thickness ratio have a distinct influence on the interfacial deflection energy release rate for multilayered ***,an unstable interfacial crack tends to occur for elastic multilayer beams with higher elastic modulus on the upper sub-beam under bending *** unstable interfacial fracture shows a decreasing interfacial deflection energy release rate with an increasing interfacial crack length.

关键词： Interfacial deflection energy release rate four-point bending J-integral extended finite element method

energy Transfer of Peptide Ions Colliding with a Self-Assembled Monolayer Surface. The Influence of Peptide Ion Size

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Chinese Journal of Chemistry 2019年第3期37卷 237-243页

作者： Meng Gu Li Yang William L Hase Jianmin Sun Jiaxu Zhang MlIT Key Laboratory of Critical Materials Technology for New energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbinHeilongjiang 150001China Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTX79401USA

Summary of main observation and conclusion Atomistic dynamics of protonated polyglycine, glyn-H^+(n = 3, 5, and 7), colliding with a fluorinated octanethiol self-assembled monolayer (F-SAM) surface has been studied by trajectory calculations. The effects of peptide size on the collision processes and energy transfer efficiencies are emphasized and discussed in detail. The simulations show that the fraction of trapping, which is related to the soft-landing process, dramatically drops with the in crease in collisi on energy, but gently increases with the peptide size. The average energy transfer to the peptide ion's internal degrees of freedom, AEint, is compared with previous experiments. The limiting probability Po of energy transfer to the surface is given by fitting a function of Poexp(—b/&). Our results suggest that the efficiencies of energy transfer are less dependent on the masses, even the categories of the peptide ions, and are determined by the character of the surfaces.

关键词： energy Transfer Peptide Ions Colliding

energy model for the Zr-based metallic glass alloy melt with clusters

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Science China(Physics,Mechanics & Astronomy) 2007年第4期50卷 460-466页

作者： YANG YuanSheng LI HuiQiang TONG WenHui Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

An energy model for the melt of bulk metallic glass (BMG) with clusters was estab- lished, the Gibbs free energy and interfacial energy for the Zr-Al-Ni ternary alloy melt with Zr2Ni clusters were calculated, and the effects of the clusters on the Gibbs free energy, interfacial energy and nucleation rate were analyzed. The results showed that the existence of the clusters in the Zr-Al-Ni ternary alloy melt enables the Gibbs free energy to decrease in the composition range where bulk metallic glass forms easily, makes the interfacial energy increase and changes the distribu- tion of the interfacial energy with the alloy composition. Because of the clusters in the melt, the Gibbs free energy of the Zr66Al8Ni26 alloy melt decreases about 0.3-1 kJ/mol and the interfacial energy between the melt and crystal nucleus increases about 0.016 J/m2. The nucleation rate of the undercooled Zr66Al8Ni26 alloy melt de- creases evidently under the influence of the clusters on Gibbs free energy and the interfacial energy, and the maximum of the nucleation rate in the melt with the Zr2Ni clusters is only about 107 mol1s1.

关键词： bulk metallic glass cluster Gibbs free energy interfacial energy

energy Conditions and Conservation Laws in LRS Bianchi Type Ⅰ Spacetimes via Noether Symmetries

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Communications in Theoretical Physics 2019年第3期71卷 298-306页

作者： Sumaira Saleem Akhtar Tahir Hussain Department of Mathematics University of Peshawar

In this paper, we have completely classified the locally rotationally symmetric(LRS) Bianchi Type Ⅰ spacetimes via Noether symmetries(NS). The usual Lagrangian corresponding to LRS Bianchi Type Ⅰ metric is used to find the set of determining equations. To achieve a complete classification, these determining equations are generally integrated to find the components of NS vector field and the metric coefficients. During this procedure, several cases arise which give different Noether algebras of dimension 5,..., 9, 11, and 17. A comparison is established between the obtained NS and the Killing and homothetic vectors. Corresponding to all NS generators, the conservation laws are stated by using Noether's theorem. The metrics which we have obtained as a result of our classification are shown to be anisotropic or perfect fluids which satisfy certain energy conditions.

关键词： Bianchi type I model Noether symmetry conservation Laws energy conditions

energy measurement system of a large-aperture high power laser experiment platform

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High Power Laser Science and Engineering 2013年第Z1期1卷 126-131页

作者： Yanwen Xia Yue Liang Sen Li Junpu Zhao Zhitao Peng Hongguang Li Hua Liu Zhihong Sun Kuixing Zheng Xiaofeng Wei Research Center of Laser Fusion CAEP Xi'an Institute of Optics and Fine Mechanics Chinese Academy of Sciences

An energy measurement system in a large-aperture high power laser experiment platform is introduced. The entire measurement system includes five calorimeters, which carry out the energy measurement of the fundamental frequency before the frequency conversion unit, remaining fundamental frequency, remaining second-harmonics, third-harmonics,as well as the energy balance measurement after the frequency conversion unit. Combinational indirect calibration and direct calibration are employed to calibrate the sampling coefficients of the calorimeters. The analysis of the data showed that, regarding the energy balance coefficients, combinational calibration approach gives a higher precision, and leads to an energy balance with 1%; and regarding the energy sampling coefficients for the various wavelengths after the frequency conversion, the results from direct and combinational calibration are consistent. The uncertainties for all energy sampling coefficients are within 3%, which guarantees the reliability of the energy measurement for the laser facility.

关键词： Laser diagnostics pulse energy calorimeter high power laser