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A multi-objective multi-memetic algorithm for network-wide conflict-free 4D flight trajectories planning

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Chinese Journal of Aeronautics 2017年第3期30卷 1161-1173页

作者： Su yan Kaiquan CAI School of Electronics and Information Engineering Beihang University Beijing 100191 China beijing Key Laboratory of Network Enabled Collaborative ATM Beijing 100191 China

Under the demand of strategic air traffic flow management and the concept of trajectory based operations（TbO）,the network-wide 4D flight trajectories planning（N4DFTP） problem has been investigated with the purpose of safely and efficiently allocating 4D trajectories（4DTs）（3D position and time） for all the flights in the whole airway *** that the introduction of large-scale 4DTs inevitably increases the problem complexity,an efficient model for strategiclevel conflict management is developed in this ***,a bi-objective N4 DFTP problem that aims to minimize both potential conflicts and the trajectory cost is *** consideration of the large-scale,high-complexity,and multi-objective characteristics of the N4DFTP problem,a multi-objective multi-memetic algorithm（MOMMA） that incorporates an evolutionary global search framework together with three problem-specific local search operators is *** is capable of rapidly and effectively allocating 4DTs via rerouting,target time controlling,and flight level ***,to balance the ability of exploitation and exploration of the algorithm,a special hybridization scheme is adopted for the integration of local and global *** studies using real air traffic data in China with different network complexities show that the proposed MOMMA is effective to solve the N4 DFTP *** solutions achieved are competitive for elaborate decision support under a TbO environment.

关键词： Air traffic flow management 4D trajectory planning Multi-memetic algorithm Multi-objective optimization Network-wide strategic conflict management

Liver mitochondrial and whole-animal level metabolic compensation in a catfish during seasonal acclimatization

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Current Zoology 2011年第1期57卷 109-115页

作者： Yulian yan Xiaojun XIE Institute of Hydrobiology and Water Environment School of Life Science Southwest University Chongqing 400715 China

To examine whether metabolic compensation during seasonal acclimatization at the liver mitochondrial level is consistent with that at the whole-animal level, respiration rates of liver mitochondria and resting metabolic rates in winter- and sum- meracclimatized southern catfish （Silurus meridionalis Chen） were measured. At 12.5, 17.5, 22.5, 27.5 and 32.5~C, the mean values of state 3 respiration rates were 12.21, 13.84, 18.96, 24.78 and 32.01 nmol O2min-1 mg-1 mitochondrial protein in the winter group, and 8.56, 9.20, 17.32, 22.74 and 26.32 nmol 02 min-1 mgq in the summer group, respectively. At the five assay temperatures the resting metabolic rates were 24.86, 42.68, 61.59, 84.10 and 125.65 mg 02 h-1 kgI body mass in the winter group, and 22.89, 40.59, 52.94, 75.13 and 109.35 mg Oz h-1 kg-1 in the summer group, respectively. Total mitochondrial respiration rates in the liver organ were estimated based on state 3 respiration rates, mitochondrial protein content and organ mass, and the mean values were 72.96, 71.87, 112.47, 167.35 and 183.27 nmol Ozmin-lin the winter group, and were 47.89, 47.39, 105.67, 138.18 and 132.29 nmol 02 min-1 in the summer group, respectively. Metabolic compensation caused by seasonal acclimatization occurred at the liver mitochondrial level and compensation at the liver organ level was found to be more efficient because of an in- crease in metabolic capacity of mitochondria and a boost in organ mass. Metabolic compensation at the whole-animal level was not detected. During seasonal acclimatization, the effect of metabolic compensation at liver mitochondrial level is inconsistent with that at the whole-animal level in the southern catfish. This may be due to different degrees of regulation of metabolic mechanisms among various tissues and organs in an acclimatized organism

关键词： Metabolic compensation Mitochondrial respiration Seasonal acclimatization Silurus meridionalis

Dynamic characteristics in an external-cavity multi-quantum-well laser

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Chinese Physics b 2018年第6期27卷 185-194页

作者： Sen-Lin yan Department of Electronic Engineering Nanjing Xiaozhuang University Nanjing 211171 China

This paper outlines our studies of bifurcation, quasi-periodic road to chaos and other dynamic characteristics in an external-cavity multi-quantum-well laser with delay optical feedback. The bistable state of the laser is predicted by finding theoretically that the gain shifts abruptly between two values due to the feedback. We make a linear stability analysis of the dynamic behavior of the laser. We predict the stability scenario by using the characteristic equation while we make an approximate analysis of the stability of the equilibrium point and discuss the quantitative criteria of bifurcation. We deduce a formula for the relaxation oscillation frequency and prove theoretically that this formula function relates to the loss of carriers transferring between well regime and barrier regime, the feedback level, the delayed time and the other intrinsic parameters. We demonstrate the dynamic distribution and double relaxation oscillation frequency abruptly changing in periodic states and find the multi-frequency characteristic in a chaotic state. We illustrate a road to chaos from a stable state to quasi-periodic states by increasing the feedback level. The effects of the transfers of carriers and the escaping of carriers on dynamic behavior are analyzed, showing that they are contrary to each other via the bifurcation diagram. Also,we show another road to chaos after bifurcation through changing the linewidth enhancement factor, the photon loss rate and the transfer rate of carriers.

关键词： bifurcation chaos multi-quantum-well laser optical feedback

Teleportation of Unknown Atomic Entangled States Using GHZ Class States

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Communications in Theoretical Physics 2008年第3期49卷 639-642页

作者： ZHAO yan Department of Physics Anhui Medical University Hefei 230032 China

We propose two physical schemes, which can teleport unknown atomic entangled states from user A （Alice） to user b （bob） via GHZ class states as quantum channel The two schemes are both based on cavity QED techniques. In the two schemes, teleportation and distillation procedures can be realized simultaneously. The second teleportation scheme is more advantageous than the first one.

关键词： teleportation unknown atomic entangled states cavity QED technique GHZ class state detuned interaction strong classical driving field

Multi-component assembly of luminescent rare earth hybrid materials

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Journal of Rare Earths 2019年第2期37卷 113-123页

作者： Qiuping Li bing yan School of Materials and Chemical Engineering Ningbo University of Technology School of Chemical Science and Engineering Tongji University

This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building units, including the other photoactive species. It covers the multi-component luminescent rare earth hybrids which was assembled with different(a) organic-inorganic polymeric units,(b)nanoporous units,(c) nanoparticle composites or(d) other developing special units. Finally, future challenges and opportunities in this field are discussed. Herein it mainly focuses on the work of yan's group in recent years.

关键词： Multi-component assembly Rare earth ions Hybrid materials Luminescence

MODELING SPATIAL AND TEMPORAL VARIATION OF A POLLUTANT IN WATER ENVIRONMENT USING THE CUbIC SPLINE SCHEME

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Journal of Hydrodynamics 2006年第6期18卷 688-697页

作者： yan Min KAHAWITA Rene College of Architecture and Civil Engineering Zhejiang University of Technology Hangzhou 310014 China Department of Civil Geological and Mining Engineering Ecole Polytechnique de Montréal Université deMontr6al Quebec H3C 3A7 Canada Department of Civil Geological and Mining Engineering Ecole Polytechnique de Montréal Université de Montréal Quebec H3C 3A7 Canada

The cubic spline integration scheme has been successfully applied for the first time to obtain solutions for the two-dimensional shallow water wave and transport equations. Its principal advantages are its high accuracy, low computational cost, and flexibility of application. The study quantitatively analyzed and predicted the variation in time and space of a solid pollutant in water environment. The infiltration, adsorption, solubility, advection, and diffusion related factors at different spatial and temporal scales were taken into consideration in the model. Experiments were conducted in this study to examine the capabilities of the cubic spline scheme, The correspondence between the numerical results and the experimental data was fair, The results were also compared with the numerical results obtained using finite difference schemes with good agreement.

关键词： numerical model cubic spline scheme,hydraulics environment pollution

Total Quantum Statistical Entropy of Reissner-Nordstrom black Holes： in Dirac Field Case

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Communications in Theoretical Physics 2005年第3期43卷 445-448页

作者： XUDian-yan InstituteofMicroelectronicsandDepartmentofComputerScienceandTechnology PekingUniversityBeijing100871China

The total quantum statistical entropy of Reissner-Nordstrom black holes inDirac field case is evaluated in this article. The space-time of the black holes is divided intothree regions: region 1 (r > r_o), region 2 (r_o > r > r_i), and region 3 (r_i > r > 0), where r_ois the radius of the outer event horizon, and Ti is the radius of the inner event horizon. The totalquantum statistical entropy of Reissner-Nordstrom black holes is S = S_1 + S_2 + S_3, where S_i (i= 1,2,3) is the entropy, contributed by regions 1,2,3. The detailed calculation shows that S_2 isneglectfully small. S_1 = w_t(π~2/45)k_b(A_o/ε~2β~3), S_3 = -w_t(π~2/45)k_b(A_i/ε~2β~3), whereA_o and A_i are, respectively, the areas of the outer and inner event horizons, w_t = 2~s[1 -2~(-(s+1))], s = d/2, d is the space-time dimension, here d = 4, s = 2. As r_i approaches r_o in theextreme case the total quantum statistical entropy of Reissner-Nordstrom black holes approacheszero.

关键词： total quantum statistical entropy Reissner-Nordstrom black hole

Effect of metal nanoparticle doping concentration on surface morphology and field emission properties of nano-diamond films

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Chinese Physics b 2021年第6期30卷 617-624页

作者： Yao Wang Sheng-Wang Yu yan-Peng Xue Hong-Jun Hei yan-Xia Wu yan-yan Shen Institute of New Carbon Materials Taiyuan University of TechnologyTaiyuan 030024China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China

Nano-diamond particles are co-deposited on Ti substrates with metal(Ti/Ni) nanoparticles(NPs) by the electrophoretic deposition(EPD) method combined with a furnace annealing at 800℃ under N_(2) atmosphere. Modifications of structural and electron field emission(EFE) properties of the metal-doped films are investigated with different metal NPs concentrations. Our results show that the surface characteristics and EFE performances of the samples are first enhanced and then reduced with metal NPs concentration increasing. both the Ti-doped and Ni-doped nano-diamond composite films exhibit optimal EFE and microstructural performances when the doping quantity is 5 mg. Remarkably enhanced EFE properties with a low turn-on field of 1.38 V/μm and a high current density of 1.32 mA/cm^(2) at an applied field of 2.94 V/μm are achieved for Ni-doped nano-diamond films, and are superior to those for Ti-doped ones. The enhancement of the EFE properties for the Ti-doped films results from the formation of the TiC-network after annealing. However, the doping of electron-rich Ni NPs and formation of high conductive graphitic phase are considered to be the factor, which results in marvelous EFE properties for these Ni-doped nano-diamond films.

关键词： diamond films metal doping electrophoretic deposition field emission properties

Applying a bilingual model to mine e-commerce satisfaction sentiment

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Journal of Management Analytics 2014年第4期1卷 285-300页

作者： Gongjun yan Wu He Hui Shi Danda b.Rawat College of business University of Southern IndianaEvenasvilleIN 47712USA Old Dominion University NorfolkVA 23529USA Georgia Southern University StatesboroGA 30460USA

In recent years we have witnessed that e-commerce has become an internationalphenomenon in which sellers often need to do business with buyers who usedifferent languages. As customers, including international customers, often makepurchase decisions based on online reviews, comments and recommendationsmade by other customers, understanding the sentiment of online commentsbecomes necessary for sellers who want to provide customized recommendationsto users for a higher level of customer satisfaction. To this end, we have recentlydeveloped a bilingual model to handle both English and Chinese user commentsposted on e-commerce websites. This paper addresses several key issues includingChinese segmentation, data mining models and systematic design. An experimentin mining user satisfaction sentiment with English and Chinese online usercomments illustrates the value of our developed bilingual model.

关键词： E-commerce text mining bilingual model recommendation system e-commerce business intelligence sentiment analysis