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车联网中基于雾计算的最小化功率开销任务卸载策略

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中国电子科学研究院学报 2019年第7期14卷 774-780页

作者：刘通重庆工程职业技术学院重庆邮电大学

LTE-V有LTE-V-Direct和LTE-V-Cell两种网络连接模式。为了解决智能车辆在两种模式下产生的大量数据请求导致的网络拥塞问题,考虑了一种在宏蜂窝基站和车辆处均部署雾计算服务器的网络结构LVF(LTE-V-Fog)。同时为了降低LVF系统的能量开销... 详细信息

LTE-V有LTE-V-Direct和LTE-V-Cell两种网络连接模式。为了解决智能车辆在两种模式下产生的大量数据请求导致的网络拥塞问题,考虑了一种在宏蜂窝基站和车辆处均部署雾计算服务器的网络结构LVF(LTE-V-Fog)。同时为了降低LVF系统的能量开销,在保证网络时延的前提下,提出了一种LTE-V网络中最小化系统功率开销的LTOS(LTE-V Task Offloading Strategy)优化策略。并以时延和功耗为限制条件,构建了最小化功率开销的数学优化模型,使用模拟退火算法对优化模型进行求解。仿真结果证明此策略在缩短任务执行时延的基础上,能够有效节约系统功耗。

关键词： LTE-V 雾计算任务卸载功耗时延

Experimental and Theoretical Study on Thermal Stability of Mixture R1234ze(E)/R32 in Organic Rankine Cycle

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Journal of Thermal Science 2023年第4期32卷 1595-1613页

作者： liu Jinyu liu Yu liu Chao XIN Liyong YU Wei Key Laboratory of Low-Grade Energy Utilization Technologies and Systems Ministry of EducationSchool of Energy and Power EngineeringChongqing UniversityChongqing400030China

The use of Organic Rankine Cycle(ORC)for renewable energy utilization and industrial waste heat recovery is currently attracting growing *** working fluids in ORC may face thermally decompose during the working *** thermal stability and pyrolysis mechanism of R1234ze(E)/R32 mixtures was studied by ReaxFF-MD simulations and DFT *** experimental results indicated that the pyrolysis temperature range is 230℃-250℃ for R1234ze(E),270℃-290℃ for R32 and 230℃-250℃ for R1234ze(E)/R32 *** cleavage of C-H,C-C bond is the main decomposition pathway of pure R32,R1234ze(E),*** decomposition rate of R32 is significantly slower than that of R1234ze(E).In the mixture R1234ze(E)/R32,R1234ze(E)can significantly promote the decomposition of R32,while R32 has a slight inhibitory effect on the decomposition of R1234ze(E).The CF3 radicals generated by the decomposition of R1234ze(E)significantly reduced the energy barrier of R32 decomposition and promoted the decomposition rate of *** H and F radical in the system is more inclined to react with R32 than R1234ze(E)due to their lower energy *** increase of the pressure and mass ratio of R1234ze(E)in the mixture system has a great promoting effect on the pyrolysis of the mixtures.

关键词： R1234ze(E)/R32 pyrolysis ReaxFF-MD DFT

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反应溅射制备AlN薄膜靶中毒机制的研究

真空科学与技术学报 2011年第6期31卷 739-742页

作者：佟洪波柳青辽宁石油化工大学机械工程学院抚顺113001

反应磁控溅射方法制备AlN薄膜是一种很普遍的方法,但采用该方法制备在衬底上形成符合计量比的AlN化合物时,在靶材表面也会形成该化合物。这就是所谓的靶中毒现象,该现象会导致溅射产额降低从而引起沉积速率下降,因此是一种不利的影响。... 详细信息

反应磁控溅射方法制备AlN薄膜是一种很普遍的方法,但采用该方法制备在衬底上形成符合计量比的AlN化合物时,在靶材表面也会形成该化合物。这就是所谓的靶中毒现象,该现象会导致溅射产额降低从而引起沉积速率下降,因此是一种不利的影响。为了调查靶中毒的机制,本文采用TRIDYN程序来研究制备AlN薄膜时靶表面化合物的形成过程。结果表明化学吸收和离子注入是中毒层形成的两个主要的机制,但是该两种机制对中毒贡献的程度是不同的。通常情况下可以只考虑离子注入机制。本文还讨论了减小靶中毒的措施,在低压下可以极大地降低靶中毒程度,但为了得到符合化学计量比的AlN薄膜,需要提高衬底和靶材的面积比。

关键词：反应溅射 TRIDYN程序 AlN薄膜靶中毒

Collectorless flotation of marmatite with pine oil

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Rare Metals 2017年第2期36卷 147-154页

作者： Zheng-Bin Deng Xiong tong Alejandro López Valdivieso Xiao Wang Xian Xie Faculty of Land and Resource Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming 650093China Yunnan Province Engineering Research Center for Reutilization of Metal Tailings Resources Kunming 650093China Laboratory of Surface Chemistry Institute of Metallurgy Universidad Autonoma de San Luis PotosiC.P.78210 San Luis PotosiMexico

The interaction between pine oil and marmatite without collectors and activators was investigated by flotation,scanning electron microscope and energy-dispersive spectrometer（SEM-EDS）,infrared（IR） spectroscopy,Zeta potential,and first-principle theory *** flotation results show that marmatite exhibits considerable floatability with the addition of pine ***-EDS results show that carbon atomic ratios on the surface are significantly high,which suggests that the flotation of marmatite is caused by the adsorption of pine *** evidence of the adsorption mechanism was given by IR,and Zeta potential examining pine oil depends on the physical adsorption on the surface *** first-principle theory calculations indicate that pine oil molecule adsorbs on Zn and Fe atom surfaces by ionic bond and covalent bond of adsorption energies of-1.23and-1.51 eV,respectively.P orbital of O atom,s orbital of Zn atom,and d orbital of Fe are the major participants.

关键词： Pine oil Marmatite Collectorless flotation

Evaluation of meteorological predictions by the WRF model at Barrow, Alaska and Summit, Greenland in the Arctic in April 2019

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Advances in Polar Science 2023年第4期34卷 352-367页

作者： ZHANG tong CAO Le LI Simeng WANG Jiandong China Meteorological Administration Aerosol-Cloud-Precipitation Key Laboratory Nanjing University of Information Science&TechnologyNanjing 210044China

Accurate meteorological predictions in the Arctic are important in response to the rapid climate change and insufficient meteorological observations in the *** this study,we adopted a high-resolution Weather Research and Forecasting(WRF)model to simulate the meteorology at two Arctic stations(Barrow and Summit)in April *** results were also evaluated by using surface measurements and statistical *** addition,weather charts during the studied time period were also used to assess the model *** results demonstrate that the WRF model is able to accurately capture the meteorological parameters for the two Arctic stations and the weather systems such as cyclones and anticyclones in the ***,we found the model performance in predicting the surface pressure the best while the performance in predicting the wind the worst among these meteorological ***,the wind predictions at these Arctic stations were found to be more accurate than those at urban stations in mid-latitude regions,due to the differences in land features and anthropogentic heat sources between these *** addition,a comparison of the simulation results showed that the prediction of meteorological conditions at Summit is superior to that at *** reasons for the deviations in temperature predictions between these two Arctic stations are uncertainties in the treatments of the sea ice and the cloud in the *** respect to the wind,the deviations may source from the overestimation of the wind over the sea and at coastal stations.

关键词： Arctic WRF meteorological parameters synoptic patterns model assessment

Testing X-ray measurements of galaxy cluster gas mass fraction using the cosmic distance-duality relation

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Research in Astronomy and Astrophysics 2013年第9期13卷 1013-1024页

作者： Xin Wang Xiao-Lei Meng Yong-Feng Huang tong-Jie Zhang School of Astronomy and Space Science Nanjing University Department of Astronomy Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Kavli Institute for Theoretical Physics China Chinese Academy of Sciences

We propose a consistency test for some recent X-ray gas mass fraction （fgas） measurements in galaxy clusters, using the cosmic distance-duality relation, Ttneory = DL（1 ＋ Z）-2/da, with luminosity distance （DL） data from the Union2 compilation of type Ia supernovae. We set Z/theory = 1, instead of assigning any red- shift parameterizations to it, and constrain the cosmological information preferred by fga8 data along with supernova observations. We adopt a new binning method in the reduction of the Union2 data, in order to minimize the statistical errors. Four data sets of X-ray gas mass fraction, which are reported by Allen et al. （two samples）, LaRoque et al. and Ettori et al., are analyzed in detail in the context of two theoretical models of fgas. The results from the analysis of Alien et al.＇s samples demonstrate the feasibility of our method. It is found that the preferred cosmology by LaRoque et al.＇s sample is consistent with its reference cosmology within the 1σ confidence level. However, for Ettori et al.＇s fgas sample, the inconsistency can reach more than a 3σ confidence level and this dataset shows special preference to an ΩA = 0 cosmology.

关键词： X-rays: galaxies: clusters -- cosmology: distance scale -- galaxies: clus-ters: general -- cosmology: observations -- supernovae: general

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基于CT图像的自动肺实质分割方法

东北大学学报（自然科学版） 2008年第7期29卷 965-967,975页

作者：贾同孟琭赵大哲王旭东北大学信息科学与工程学院辽宁沈阳110004

在肺癌、肺气肿等肺部疾病计算机辅助诊断方法中,肺实质分割是最核心的步骤.提出一种基于三维CT图像序列的新的自动肺实质分割方法,综合利用了阈值分割、区域增长及数学形态学等算法,并在特定体层通过图搜索算法精确定位左右肺前后连接... 详细信息

在肺癌、肺气肿等肺部疾病计算机辅助诊断方法中,肺实质分割是最核心的步骤.提出一种基于三维CT图像序列的新的自动肺实质分割方法,综合利用了阈值分割、区域增长及数学形态学等算法,并在特定体层通过图搜索算法精确定位左右肺前后连接线狭窄区域,有效解决了肺实质边缘结节易分割遗漏及左右肺分离的难题.通过多组胸部CT序列图像的实验证明,该方法对于肺实质分割非常精确有效.

关键词：计算机辅助诊断图像分割肺结节检测肺实质分割 CT图像

Fishbone Instability Excited by Electrons in a Tokamak

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Chinese Physics Letters 2001年第9期18卷 1227-1229页

作者： VAN Long-Wen DONG Jia-Qi DING Xuan-tong liu Yi GUO Gan-Cheng WANG En-Yao HL-1M team Southwestern Institute of Physics P.O.Box 432Chengdu 610041

Fishbone instability excited by electrons in tokamak plasma is investigated theoretically and experimentally. The analysis of mode precession resonance indicates that the instability can be excited by barely trapped supratlermal electrons. The fishbone instability of electrons is more easily excited in the region of negative magnetic shear than that of positive magnetic shear and it is first observed by using electron cyclotron resonance heating in an HL-1M tokamak.

关键词： tokamak Electron excited

Lifetime of Doubly Charmed Baryons

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Communications in Theoretical Physics 2008年第4期49卷 993-1000页

作者： CHANG Chao-Hsi LI tong LI Xue-Qian WANG Yu-Ming CCAST （World Laboratory） P.O. Box 8730 Beijing 100080 China Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China Department of Physics Nankai University Tianjin 300071 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918 Beijing 100049 China

In this work, we evaluate the lifetimes of the doubly charmed baryons Ξcc^＋ ,Ξcc^＋＋, and Ωcc^＋. We carefully calculate the non-spectator contributions at the quark level, where the Cabibbo-suppressed diagrams are also included. The hadronic matrix elements are evaluated in the simple non-relativistic harmonic oscillator model. Our numerical results are generally consistent with that obtained by other authors who used the diquark model. However, all the theoretical predictions on the lifetimes are one order larger than the upper limit set by the recent SELEX measurement. This discrepancy would be clarified by the future experiment. If more accurate experiment still confirms the value of the SELEX collaboration, there must be some unknown mechanism to be explored.

关键词： doubly charmed baryons harmonic oscillator model