检索结果-南通市图书馆

Top—Higgs ht^0 and the Process γγ→ZZ

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2003年第6期39卷 681-684页

作者： YUEChong-xing ZHAOXian-lin ZHANGYan-Ming LIHong DepartmentofPhysics LiaoningnormaluniversityDalian116029China DepartmentofPhysics HenanEducationInstituteZhengzhou450014China CollegeofPhysicsandInformationengineering HenannormalUniversityXinxiang453002China

In the context of topcolor-assisted technicolor(TC2) models,we calculate the s-channel contributions of the top-Higgs ht^0 to the process γγ→*** find that,for reasonable ranges of the paramters,ht^0 can give significant contributions to this process,when the top-Higgs mass approximately equals to the center-of-mass energy s and the free parameter ε=0.01,the cross section can reach 161 *** may be detected in the γγ collisions based on the future e+e- ***,the process γγ→ZZ may be used to probe the top-Higgs and further test TC2 models in γγ collisions.

关键词： TC2模型粒子物理学希格斯介子 Higgs介子横截面相互作用 QCD 量子色动力学夸克

Self-assembly Behavior of Metal Halide Perovskite Nanocrystals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2022年第18期40卷 2239-2248页

作者： Zhuoying Yang Shaomin Peng Fan lin Pengfei Wang Guichuan xing lin Yu Key Laboratory of Clean Chemistry Technology of Guangdong Regular Higher Education Institutions Guangdong Provincial Key Laboratory of Plant Resources BiorefinerySchool of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhouGuangdong510006 China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacaoSAR999078 China

The self-assembled metal halide perovskite(MHP)nanocrystal superlattices have attracted many researchers due to their exceptional optical and electrical *** bottom-up self-assembly can be facile to generate ideal and periodic *** superlattices’stability can be improved and the photoluminescence lifetime can be extended by an order of ***,due to lack of a comprehensive and systematic understanding of the internal interactions on self-assembled processes now,superlattices cannot be obtained controllably and play full use of their ***,gaining a deep insight of interaction forces about self-assemblies is the premise of designing and controlling the degree of self-assembly so as to prepare ideal *** this review,the definitions and functions of driving forces including van der Waals forces,electrostatic interactions and hydrogen bonds are ***,we aim to explore the dominant factors affecting the driving forces,which can make a difference in the process of MHP *** on current researches,we emphasize on three aspects−the core of nanocrystals,surface ligands and solvents−to clarify their critical roles in controlling the driving ***,the outlooks and perspectives of how to facilitate the MHP self-assembly and their application on blue light emitting diodes are discussed.

关键词： Metal halide perovskite Self assembly Nanostructures Surface ligand|Solvent effects

Novel hyperbranched polyimides from 2,6,12-triaminotriptycene

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第9期19卷 1127-1130页

作者： Zhen Xu xing Quan Xiong lin Cheng Department of Materials Science ＆ Engineering Huaqiao University Quanzhou 362021 China

The monomer 2,6,12-triaminotriptycene was synthesized and the structure was confirmed by IR and 1H NMR spectra. Hyperbranched polyimides modified with different terminal groups were obtained from precursors, anhydride- and aminoterminated hyperbranched poly（amic acid）s from polymerization of A2 ＋ B3 system. From gel permeation chromatograrn （GPC） characterization, representative products had high molecular weight. All polymers had good solubility in CHCl3, DMF and tetrahydrofuran （THF）, and performed no detective Tgs in the range of 50-300 ℃ and high Tds above 455 ℃ when 5% weight loss.

关键词： Triptycene Hyperbranched polymer Polyimides

Comparison of multinomial logistic regression and logistic regression： which is more efficient in allocating land use？

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2014年第4期8卷 512-523页

作者： Yingzhi lin Xiangzheng DENG xing LI Enjun MA School of Mathematics and Physics China University of Geosciences Wuhan 430074 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

Spatially explicit simulation of land use change is the basis for estimating the effects of land use and cover change on energy fluxes, ecology and the environment. At the pixel level, logistic regression is one of the most common approaches used in spatially explicit land use allocation models to determine the relationship between land use and its causal factors in driving land use change, and thereby to evaluate land use suitability. However, these models have a drawback in that they do not determine/ allocate land use based on the direct relationship between land use change and its driving factors. Consequently, a multinomial logistic regression method was introduced to address this flaw, and thereby, judge the suitability of a type of land use in any given pixel in a case study area of the Jiangxi Province, China. A comparison of the two regression methods indicated that the proportion of correctly allocated pixels using multinomial logistic regression was 92.98%, which was 8.47% higher than that obtained using logistic regression. Paired t-test results also showed that pixels were more clearly distinguished by multinomial logistic regression than by logistic regression. In conclusion, multinomial logistic regression is a more efficient and accurate method for the spatial allocation of land use changes. The application of this method in future land use change studies may improve the accuracy of predicting the effects of land use and cover change on energy fluxes, ecology, and environment.

关键词： multinomial logistic regression land usechange logistic regression land use suitability land useallocation

Formation of the CME Leading Edge Observed in the 2003 February 18 Event

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 741-750页

作者： xing-Ming Bao Hong-Qi Zhang Jun lin National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge MA 02138 USA

This work investigates a typical coronal mass ejection （CME） observed on 2003 February 18, by various space and ground instruments, in white light, Ha, EUV and X- ray. The Ha and EUV images indicate that the CME started with the eruption of a long filament located near the solar northwest limb. The white light coronal images show that the CME initiated with the rarefaction of a region above the solar limb and followed by the formation of a bright arcade at the boundary of the rarefying region at height 0.46 Re above the solar surface. The rarefying process synchronized with the slow rising phase of the eruptive filament, and the CME leading edge was observed to form as the latter started to accelerate. The lower part of the filament brightened in Ha as the filament rose to a certain height and parts of the filament was visible in the GOES X-ray images during the rise. These brightenings imply that the filament may be heated by the magnetic reconnection below the filament in the early stage of the eruption. We suggest that a possible mechanism which leads to the formation of the CME leading edge and cavity is the magnetic reconnection which takes place below the filament after the filament has reached a certain height.

关键词： Sun coronal mass ejections (CMEs) - Sun filaments - Sun flares

QoS multicast routing scheme using QGA in IP/DWDM networks

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 95-100页

作者： xing Huan-lai BAI lin JI Yue-feng Key Laboratory of Optical Communications and Lightwave Techno ogies Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies multi-constraints least-cost multicast routing problem in internet protocol over dense wavelength division multiplexing （IP/DWDM） networks. To address this problem, an individual-difference-based quantum genetic algorithm （IDQGA） is proposed. This algorithm considers individual differences among chromosomes by introducing an adaptive rotation angle step determination scheme and a grouping-based quantum mutation operation. Simulations are conducted over network topologies. The results indicate that compared with other heuristic algorithms, IDQGA has better optimal performance on solving quality of service （QoS） multicast routing problem in IP/DWDM networks and is characterized by strong robustness, high success ratio and excellent capability on global searching.

关键词： IP-over-DWDM multicast QoS quantum genetic algorithm

Structural, magnetic and electronic properties of the iron-chalcogenide AxFe2-ySe2 （A=K, Cs, Rb, and TI, etc.） superconductors

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2011年第4期6卷 410-428页

作者： Dai-xiang Mou lin Zhao xing-jiang Zhou National Laboratory for Superconductivity Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

The latest discovery of a new iron-chalcogenide superconductor AXFe2-ySe2 （A =K, Cs, Rb, and Tl, etc.） has attracted much attention due to a number of its unique characteristics, such as the possible insulating state of the parent compound, the existence of Fe-vacancy and its ordering, a new form of magnetic structure and its interplay with superconductivity, and the peculiar electronic structures that are distinct from other Fe-based superconductors. In this paper, we present a brief review on the structural, magnetic and electronic properties of this new superconductor, with an emphasis on the electronic structure and superconducting gap. Issues and future perspectives are discussed at the end of the paper.

关键词： superconductor iron-chalcogenides electronic structure photoemission Fermi science superconducting gap crystal structure magnetic structure

Steiner Tree Based Optimal Resource Caching Scheme in Fog Computing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2015年第8期12卷 161-168页

作者： SU Jingtao lin Fuhong ZHOU Xianwei Lü xing School of Computer and Communication Engineering University of Science and Technology Beijing School of Science Beijing Jiaotong University

Fog Computing is a new platform that can serve mobile devices in the local area. In Fog Computing, the resources need to be shared or cached in the widely deployed Fog clusters. In this paper, we propose a Steiner tree based caching scheme, in which the Fog servers, when caching resources, first produce a Steiner tree to minimize the total path weight(or cost) such that the cost of resource caching using this tree could be minimized. Then we give a running illustration to show how the Fog Computing works and we compare the traditional shortest path scheme with the proposed one. The outcome shows that the Steiner tree based scheme could work more efficiently.

关键词： steiner Tree resource caching fogcomputing architecture

Amygdala-Inspired Affective Computing: to Realize Personalized Intracranial Emotions with Accurately Observed External Emotions

在线全文

学校读者我要写书评

暂无评论

China Communications 2019年第8期16卷 115-129页

作者： Chao Gong Fuhong lin Xianwei Zhou xing Lü School of Computer and Communication Engineering University of Science and Technology Beijing

Artificial intelligence technology has revolutionized every industry and trade in recent years. However, its own development is encountering bottlenecks that it is unable to implement empathy with human emotions. So affective computing is getting more attention from researchers. In this paper, we propose an amygdala-inspired affective computing framework to realize the recognition of all kinds of human personalized emotions. Similar to the amygdala, the instantaneous emergency emotion is first computed more quickly in a low-redundancy convolutional neural network compressed by pruning and weight sharing with hashing trick. Then, the real-time process emotion is identified more accurately by the memory level neural networks, which is good at handling time-related signals. Finally, the intracranial emotion is recognized in personalized hidden Markov models. We demonstrate on Facial Expression of Emotion Dataset and the recognition accuracy of external emotions(including the emergency emotion and the process emotion) reached 85.72%. And the experimental results proved that the personalized affective model can generate desired intracranial emotions as expected.

关键词： affective computing emotion recognition personalized machines external emotions intracranial emotions