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TMAHS:a truthful multi-unit double auction framework for heterogeneous spectrum in secondary market
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作者 Li Xin Xie Gang Gao Jinchun 《中国邮电高校学报:英文版》 EI CSCD 2019年第1期82-94,共13页
Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity.In real communication system,such as broadband communication,the utilization of spectr... Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity.In real communication system,such as broadband communication,the utilization of spectrum resource is various because of different requirements and complex application scenarios.So,these schemes cannot be directly applied to the above wireless communication system.To solve this problem,a new model where sellers/buyers can sell/buy multi-unit for heterogeneous spectrum was proposed and a truthful multi-unit double auction framework was designed for heterogeneous spectrum trading.A valuation function is first applied to represent the buyer's true valuation of the sub-band and reflect the buyer's satisfaction degree and a novel concept termed'virtual player'was introduced.Then the buyer group was constructed based on the conflict graph to reuse the same spectruin among interference-free buyers in both spatial and temporal domains.The winner determination strategy and algorithm of clearing price were designed elaborately.According to the theoretical analysis,the scheme can satisfy three critical economic properties:truthfulness,individual rationality,and budget balance.Finally,simulation results show that the proposed scheme can achieve better user satisfaction,auction efficiency and spectrum reuse rate for the real communication system.The proposed auction framework is practical and effective. 展开更多
关键词 SPECTRUM AUCTION double AUCTION SPECTRUM REUSE HETEROGENEOUS SPECTRUM MULTI-UNIT VALUATION function
Optimal Energy-Efficient Transmission for Hybrid Spectrum Sharing in Cooperative Cognitive Radio Networks 预览
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作者 Linna Hu Rui Shi +3 位作者 Minghe Mao Zhiyu Chen Hongxi Zhou Weiliang Li 《中国通信:英文版》 SCIE CSCD 2019年第6期150-161,共12页
In order to improve the energy efficiency(EE)in cognitive radio(CR),this paper investigates the joint design of cooperative spectrum sensing time and the power control optimization problem for the secondary user syste... In order to improve the energy efficiency(EE)in cognitive radio(CR),this paper investigates the joint design of cooperative spectrum sensing time and the power control optimization problem for the secondary user systems to achieve the maximum energy efficiency in a cognitive network based on hybrid spectrum sharing,meanwhile considering the maximum transmit power,user quality of service(QoS)requirements,interference limitations,and primary user protection.The optimization of energy efficient sensing time and power allocation is formulated as a non-convex optimization problem.The Dinkelbach’s method is adopted to solve this problem and to transform the non-convex optimization problem in fractional form into an equivalent optimization problem in the form of subtraction.Then,an iterative power allocation algorithm is proposed to solve the optimization problem.The simulation results show the effectiveness of the proposed algorithms for energy-efficient resource allocation in the cognitive network. 展开更多
关键词 cognitive radio networks COOPERATIVE SPECTRUM SENSING ENERGY-EFFICIENCY HYBRID SPECTRUM sharing power control SENSING time optimization
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Observational constraints on running vacuum model
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作者 张进军 Chung-Chi Lee 耿朝强 《中国物理C:英文版》 SCIE CAS CSCD 2019年第2期132-137,共6页
We investigate the power spectra of the CMB temperature and matter density in the running vacuum model(RVM) with the time-dependent cosmological constant of A=3 vH2+ Λ0, where H is the Hubble parameter. In this model... We investigate the power spectra of the CMB temperature and matter density in the running vacuum model(RVM) with the time-dependent cosmological constant of A=3 vH2+ Λ0, where H is the Hubble parameter. In this model, dark energy decreases in time and decays to both matter and radiation. By using the Markov chain Monte Carlo method, we constrain the model parameter v as well as the cosmological observables. Explicitly, we obtain v ≤1.54× 10-4(68% confidence level) in the RVM with the best-fit χRVM2 =13968.8, which is slightly smaller thanχΛCDM2= 13969.8 in the ΛCDM model of v = 0. 展开更多
关键词 MATTER power SPECTRUM running VACUUM MODEL CMB temperature SPECTRUM COSMOLOGICAL constant
A Dynamic Distributed Spectrum Allocation Mechanism Based on Game Model in Fog Radio Access Networks 预览
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作者 Yao Yu Shumei Liu +1 位作者 Zhongshi Tian Siyu Wang 《中国通信:英文版》 SCIE CSCD 2019年第3期12-21,共10页
With the explosive growth of highspeed wireless data demand and the number of mobile devices,fog radio access networks(F-RAN)with multi-layer network structure becomes a hot topic in recent research.Meanwhile,due to t... With the explosive growth of highspeed wireless data demand and the number of mobile devices,fog radio access networks(F-RAN)with multi-layer network structure becomes a hot topic in recent research.Meanwhile,due to the rapid growth of mobile communication traffic,high cost and the scarcity of wireless resources,it is especially important to develop an efficient radio resource management mechanism.In this paper,we focus on the shortcomings of resource waste,and we consider the actual situation of base station dynamic coverage and user requirements.We propose a spectrum pricing and allocation scheme based on Stackelberg game model under F-RAN framework,realizing the allocation of resource on demand.This scheme studies the double game between the users and the operators,as well as between the traditional operators and the virtual operators,maximizing the profits of the operators.At the same time,spectrum reuse technology is adopted to improve the utilization of network resource.By analyzing the simulation results,it is verified that our proposed scheme can not only avoid resource waste,but also effectively improve the operator’s revenue efficiency and overall network resource utilization. 展开更多
关键词 FOG radio access networks(F-RAN) game theory SPECTRUM REUSE technology base station DYNAMIC COVERAGE SPECTRUM PRICING and allocation
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基于Unity 3D的光谱实验教学系统研究 预览
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作者 刘钊 徐富新 《计算机技术与发展》 2019年第6期119-124,共6页
在教学中运用虚拟现实技术是当今的一个热门话题。教育正在进入网络的时代,这既是一种趋势,也是教育的未来。对实验室进行虚拟化技术的研发,通过先进的计算机技术以更好地满足对教学的需求。文中将建模软件3DMax和虚拟仿真软件Unity3D... 在教学中运用虚拟现实技术是当今的一个热门话题。教育正在进入网络的时代,这既是一种趋势,也是教育的未来。对实验室进行虚拟化技术的研发,通过先进的计算机技术以更好地满足对教学的需求。文中将建模软件3DMax和虚拟仿真软件Unity3D应用于物理实验教学,结合虚拟现实的特点,设计了光栅光谱虚拟仿真实验系统,给出了系统的整体结构和部分实现的关键技术,模拟一个真实的实验环境。该系统采用基于Bmob后端云服务器,以节约成本,提高开发效率。实验内容结合了3D和互动仿真的两大优点,界面直观、操作简单,通过对MVC登录设计、实验操作交互技术、动态光谱图技术的研究,结合实验实际需求,使得光学实验变得简单。学生能够更快掌握原理,熟悉实验操作来缩短真实实验周期,提高实验教学的效率,达到良好的实验教学效果。 展开更多
关键词 3DMax UNITY3D 虚拟仿真 物理实验 光谱
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蓝光与眼睛 预览
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作者 成知函 John Hayes(指导) 《中国眼镜科技杂志》 2019年第3期110-112,共3页
蓝光是光谱中波长为400nm~500nm的可见光。蓝光可分为短波蓝光即有害蓝光,和长波蓝光即有益蓝光。短波蓝光危害人们的视力,并导致特定疾病,而长波蓝光则有助于人们维护正常的生理功能,调节生物节律,并治疗特定疾病。目前防控蓝光的方法... 蓝光是光谱中波长为400nm~500nm的可见光。蓝光可分为短波蓝光即有害蓝光,和长波蓝光即有益蓝光。短波蓝光危害人们的视力,并导致特定疾病,而长波蓝光则有助于人们维护正常的生理功能,调节生物节律,并治疗特定疾病。目前防控蓝光的方法正在逐渐发明与完善中。 展开更多
关键词 短波蓝光 长波蓝光 光谱 视力
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Carbon deposition in porous nickel/yttria-stabilized zirconia anode under methane atmosphere 预览
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作者 Zhi-yuan Chen Li-jun Wang +3 位作者 Xiao-jia Du Zai-hong Sun Fu-shen Li Kuo-Chih Chou 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第3期350-359,共10页
A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exc... A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exceeded 700℃. The reactivity of carbon decreased with increasing deposition temperature. Filamentous carbon was deposited from 400 to 600℃, whereas flake carbon was deposited at 700 and 800℃. With increasing temperature, the intensity ratio of the D band over the sum of the G and D bands was constant at the beginning and then decreased with the transformation of the carbon morphology. The crystallite size increased from 2.9 to 13 nm with increasing temperature. The results also indicated that the structure of the deposited carbon was better ordered with increasing deposition temperature. In comparison with pure Ni powders, the interaction between the YSZ substrate and Ni particles could not only modify the carbon deposition kinetics but also reduce the temperature effect on the structure and reactivity variation of carbon. 展开更多
关键词 solid oxide FUEL cell COKING RAMAN spectrum HYDROCARBON FUEL ANODE
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Influence of rooftop telecommunication tower on set back-step back building resting on different ground slopes 预览
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作者 Amit Thakur Deepankar Kumar Ashish Surender Kumar Verma 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第2期351-362,共12页
In the hilly region due to scarcity of the plain area, buildings like set back-step back are more often used and also as a big surge in the telecommunication industries, rooftop tower adaptation is very common story n... In the hilly region due to scarcity of the plain area, buildings like set back-step back are more often used and also as a big surge in the telecommunication industries, rooftop tower adaptation is very common story nowadays. In the present study an analogy has been drawn to find out the influence of the rooftop telecommunication tower on the setback-step back building resting on ground at 20° and 30° slopes. A dynamic analysis has been performed and compared on the 4 legged angled section telecommunication tower which is located on the roof top of set back-step back building by varying positions of tower with the existing host structure built up on ground slope of 20° and 30° in both directions(X and Y). 展开更多
关键词 rooftop telecommunication tower SET back-step BACK BUILDING response spectrum analysis steel RC frame earthquake SAP2000
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The Plasmonic Resonances of a Bowtie Antenna 预览
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作者 Eric Bonnetier Charles Dapogny +1 位作者 Faouzi Triki Hai Zhang 《分析理论与应用:英文刊》 CSCD 2019年第1期85-116,共32页
Metallic bowtie-shaped nanostructures are very interesting objects in optics,due to their capability of localizing and enhancing electromagnetic fields in the vicinity of their central neck.In this article,we investig... Metallic bowtie-shaped nanostructures are very interesting objects in optics,due to their capability of localizing and enhancing electromagnetic fields in the vicinity of their central neck.In this article,we investigate the electrostatic plasmonic resonances of two-dimensional bowtie-shaped domains by looking at the spectrum of their Poincare variational operator.In particular,we show that the latter only consists of essential spectrum and fills the whole interval[0,1].This behavior is very different from what occurs in the counterpart situation of a bowtie domain with only close-totouching wings,a case where the essential spectrum of the Poincare variational operator is reduced to an interval oess strictly containing in[0,1].We provide an explanation for this difference by showing that the spectrum of the Poincare variational operator of bowtie-shaped domains with close-to-touching wings has eigenvalues which densify and eventually fill the remaining parts of[0,1]\σess as the distance between the two wings tends to zero. 展开更多
关键词 Neumann-Poincaréoperator CORNER SINGULARITY SPECTRUM RESONANCE
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激光解离四氯化碳的光谱研究 预览
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作者 付鹏 臧学平 《宿州学院学报》 2019年第4期64-66,共3页
利用激光溅射-超声分子束冷却技术的方法,对四氯化碳的激光解离光谱进行了研究,实验中发现了C+、Cl35+、Cl37+、CCl35+、CCl37+、CCl235+、CCl237+和CCl335+、CCl337+等离子信号。对其解离过程和原因进行了分析,发现不同通道的产物离子... 利用激光溅射-超声分子束冷却技术的方法,对四氯化碳的激光解离光谱进行了研究,实验中发现了C+、Cl35+、Cl37+、CCl35+、CCl37+、CCl235+、CCl237+和CCl335+、CCl337+等离子信号。对其解离过程和原因进行了分析,发现不同通道的产物离子峰值信号不同,氯同位素产物离子信号强度与其自然界中的丰度比相吻合。实验表明产物离子主要是多光子吸收产生共振及离子间碰撞电离产生的。 展开更多
关键词 激光解离 多光子吸收 四氯化碳 光谱
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Correlation of Gut Microbiome Between ASD Children and Mothers and Potential Biomarkers for Risk Assessment
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作者 Ning Li Junjie Yang +14 位作者 Jiaming Zhang Cheng Liang Ying Wang Bin Chen Changying Zhao Jingwen Wang Guangye Zhang Dongmei Zhao Yi Liu Lehai Zhang Jun Yang Guimei Li Zhongtao Gai Lei Zhang Guoping Zhao 《基因组蛋白质组与生物信息学报:英文版》 CAS CSCD 2019年第1期26-38,共13页
Variation of maternal gut microbiota may increase the risk of autism spectrum disorders(ASDs)in offspring.Animal studies have indicated that maternal gut microbiota is related to neurodevelopmental abnormalities in mo... Variation of maternal gut microbiota may increase the risk of autism spectrum disorders(ASDs)in offspring.Animal studies have indicated that maternal gut microbiota is related to neurodevelopmental abnormalities in mouse offspring,while it is unclear whether there is a correlation between gut microbiota of ASD children and their mothers.We examined the relationships between gut microbiome profiles of ASD children and those of their mothers,and evaluated the clinical discriminatory power of discovered bacterial biomarkers.Gut microbiome was profiled and evaluated by 16S ribosomal RNA gene sequencing in stool samples of 59 mother-child pairs of ASD children and 30 matched mother-child pairs of healthy children.Significant differences were observed in the gut microbiome composition between ASD and healthy children in our Chinese cohort.Several unique bacterial biomarkers,such as Alcaligenaceae and Acinetobacter,were identified.Mothers of ASD children had more Proteobacteria,Alphaproteobacteria,Moraxellaceae,and Acinetobacter than mothers of healthy children.There was a clear correlation between gut microbiome profiles of children and their mothers;however,children with ASD still had unique bacterial biomarkers,such as Alcaligenaceae,Enterobacteriaceae,and Clostridium.Candidate biomarkers discovered in this study had remarkable discriminatory power.The identified patterns of mother-child gut microbiome profiles may be important for assessing risks during the early stage and planning of person?alized treatment and prevention of ASD via microbiota modulation. 展开更多
关键词 AUTISM spectrum DISORDERS GUT MICROBIOME Biomarker Mother-child pair Microbiota-gut-immunebrain axis
The Normalized Laplacian Spectrum of Subdivision Vertex-Edge Corona for Graphs
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作者 Muchun LI You ZHANG Fei WEN 《数学研究及应用:英文版》 CSCD 2019年第3期221-232,共12页
A subdivision vertex-edge corona G1S?(∪ G3E) is a graph that consists of S(G1),|V(G1)| copies of G2 and |I(G1)| copies of G3 by joining the i-th vertex in V(G1) to each vertex in the i-th copy of G2 and i-th vertex o... A subdivision vertex-edge corona G1S?(∪ G3E) is a graph that consists of S(G1),|V(G1)| copies of G2 and |I(G1)| copies of G3 by joining the i-th vertex in V(G1) to each vertex in the i-th copy of G2 and i-th vertex of I(G1) to each vertex in the i-th copy of G3.In this paper, we determine the normalized Laplacian spectrum of G1S?(G2V∪ G3E) in terms of the corresponding normalized Laplacian spectra of three connected regular graphs G1, G2 and G3. As applications, we construct some non-regular normalized Laplacian cospectral graphs. In addition, we also give the multiplicative degree-Kirchhoff index, the Kemeny’s constant and the number of the spanning trees of G1S?(G2V∪ G3E) on three regular graphs. 展开更多
关键词 normalized Laplacian spectrum cospectral GRAPHS SPANNING trees SUBDIVISION vertex-edge CORONA
基于程序谱的方法级别错误定位技术 预览
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作者 徐迟 苏小红 王甜甜 《智能计算机与应用》 2019年第2期251-254,共4页
自动化的软件错误定位是软件调试过程中的一个热点问题,旨在更高效地发现软件中的错误。然而,目前的软件错误定位技术大多是针对语句级别的定位,而语句级别的定位精度不是很高,一旦定位失败,程序员就会很难发现软件中的错误。为了进一... 自动化的软件错误定位是软件调试过程中的一个热点问题,旨在更高效地发现软件中的错误。然而,目前的软件错误定位技术大多是针对语句级别的定位,而语句级别的定位精度不是很高,一旦定位失败,程序员就会很难发现软件中的错误。为了进一步地提高软件错误定位的效率,本文提出了一种基于程序谱的方法级别错误定位技术。方法级别的错误定位相比于语句级别的错误定位,其优势在于,方法级别定位的效率会更高,可以首先确定bug语句存在于待测程序的某个方法中,然后通过人工调试的方法进一步确定bug语句的具体位置。本文首先提出了一种基于程序谱的方法级别错误定位方法,随后,对本文的方法进行了实验分析。实验表明,本文方法能够有效提高方法级别错误定位的精度。 展开更多
关键词 错误定位 程序谱 方法级别
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Multi-Strategy Dynamic Spectrum Access in Cognitive Radio Networks:Modeling,Analysis and Optimization 预览
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作者 Yi Yang Qinyu Zhang +3 位作者 Ye Wang Takahiro Emoto Masatake Akutagawa Shinsuke Konaka 《中国通信:英文版》 SCIE CSCD 2019年第3期103-121,共19页
Dynamic spectrum access(DSA)based on cognitive radios(CR)technique is an effective approach to address the“spectrum scarcity”issue.However,traditional CR-enabled DSA system employs only single DSA strategy,which mig... Dynamic spectrum access(DSA)based on cognitive radios(CR)technique is an effective approach to address the“spectrum scarcity”issue.However,traditional CR-enabled DSA system employs only single DSA strategy,which might not be suited to the dynamic network environment.In this paper,we propose a multi-strategy DSA(MS-DSA)system,where the primary and the secondary system share spectrum resources with multiple DSA strategies simultaneously.To analyze the performance of the proposed MS-DSA system,we model it as a continuous-time Markov chain(CTMC)and derive the expressions to compute the corresponding performance metrics.Based on this,we define a utility function involving the concerns of effective throughput,interference quantity on primary users,and spectrum leasing cost.Two optimization schemes,named as spectrum allocation and false alarm probability selection,are proposed to maximize the utility function.Finally,numerical simulations are provided to validate our analysis and demonstrate that the performance can be significantly improved caused by virtues of the proposed MS-DSA system. 展开更多
关键词 COGNITIVE RADIO networks dynamic SPECTRUM access multi-strategy performance analysis optimization
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Spectrum Density Factor of Photons and Its Application in the Casimir Force
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作者 高先龙 孟烨铭 +1 位作者 吴飓昊 汪克林 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期397-402,共6页
The observables of continuous eigenvalues are de?ned in an in?nite-dimensional ket space. The complete set of such eigenstates demands a spectrum density factor, for example, for the photons in the free space and elec... The observables of continuous eigenvalues are de?ned in an in?nite-dimensional ket space. The complete set of such eigenstates demands a spectrum density factor, for example, for the photons in the free space and electrons in the vacuum. From the derivation of the Casimir force without an arti?cial regulator we determine the explicit expression of the spectrum density factor for the photon ?eld to be an exponential function. The undetermined constant in the function is ?xed by the experimental data for the Lamb shift. With that, we predict that there exists a correction to the Casimir force. 展开更多
关键词 SPECTRUM DENSITY FACTOR CASIMIR force Lamb shift
Vibration and acoustic radiation of bogie area under random excitation in high-speed trains 预览
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作者 Dongzhen Wang Jianmin Ge 《现代交通学报:英文版》 2019年第2期120-128,共9页
Based on the experiments on a platform with real vehicle structure and finite element simulation, the vibration and interior acoustic radiation under random excitations of high-speed trains’ bogie area were studied. ... Based on the experiments on a platform with real vehicle structure and finite element simulation, the vibration and interior acoustic radiation under random excitations of high-speed trains’ bogie area were studied. Firstly, combined with line tests, a vehicle body with a length of 7 m was used as the research object. By comparing the results of experiment and simulation, the accuracy of the finite element model was verified. Secondly, the power spectral density curves at typical measuring points in bogie area were obtained by processing and calculating the line test data, which was measured when the vehicle ran at high speeds, and the standard vibration spectrum of the bogie area was obtained by the extreme envelope method. Furthermore, the random vibration test and simulation prediction analysis of the real vehicle structure were carried out to further verify the accuracy of the noise and vibration prediction model. Finally, according to the vibration and acoustic radiation theory, the indirect boundary element method was adopted to predict the acoustic response of the real vehicle. The analysis shows that the simulated power spectral density curves of acceleration and sound pressure level are highly consistent with the experimental ones, and the error between the simulated prediction and the experimental result is within the allowable range of 3 dB. 展开更多
关键词 HIGH-SPEED TRAINS Standard vibration SPECTRUM Indirect boundary element method RANDOM EXCITATION Acoustic radiation
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后工业时代的社会时间悖论 预览
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作者 杨洁高 孙尚诚 《武汉理工大学学报:社会科学版》 2019年第3期48-53,共6页
社会时间不同于自然时间,它是质性的,是人类生存方式的产物。社会实在差异决定了社会时间模式差异。基于群体类型化,社会时间分为八类;基于谱系学,社会时间分为四类。后工业时代的社会时间既包容所有类别,又不受分类约束。在由时尚形式... 社会时间不同于自然时间,它是质性的,是人类生存方式的产物。社会实在差异决定了社会时间模式差异。基于群体类型化,社会时间分为八类;基于谱系学,社会时间分为四类。后工业时代的社会时间既包容所有类别,又不受分类约束。在由时尚形式确立的现在时间轴心作用下,后工业时代社会时间按悖论方式展开。后工业时代的基本社会时间悖论是资本主义经济时间悖论。这一悖论的生存矛盾螺线体现的是不断加大的时间压力,时间压力使其它社会矛盾隐藏于过去、现在、未来的时间矛盾之中,而现代消费将使时间矛盾尖锐。 展开更多
关键词 社会时间 类型 谱系 社会时间悖论 时间压力
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Reliability and validity of the translated Chinese version of Autism Spectrum Rating Scale (2-5 years)
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作者 Hao Zhou Chun-Pei Li +7 位作者 Yi Huang Xiao-Bing Zou Xue-Rong Luo Li-Jie Wu Lan Zhang Xiu Xu Wei-Li Yan Yi Wang 《世界儿科杂志(英文版)》 2019年第1期49-56,共8页
Background Early autism screening is of great value,but there is lack of a screening tool of early age (2-5 years) in China.The Autism Spectrum Rating Scale (ASRS,2-5 years) is a newly developed autism screening tool ... Background Early autism screening is of great value,but there is lack of a screening tool of early age (2-5 years) in China.The Autism Spectrum Rating Scale (ASRS,2-5 years) is a newly developed autism screening tool in the USA.This study aimed to evaluate the reliability and validity of the translated Chinese version of ASRS (C_ASRS) in Chinese children population before its application in China for early autism screening.Methods Caregivers of general children aged 2-5 years from 17 kindergartens and autism spectrum disorder (ASD) cases from five special education schools in five cities were recruited to complete the C_ASRS.1910 valid questionnaires from kindergarteners and 192 from ASD cases were included for analyses.Results The item reliability (Cronbach's alpha) was more than 0.80 in the screening scale and DSM-5 scale,and 0.51-0.81 in the treatment scale.ASD cases scored higher on total score and most subscales compared to the kindergarteners (Cohen's d ranging from 1.34 to 3.37).C_ASRS showed good discriminatory validity with an area under the receiver operating characteristic curve of 0.850 (95% confidence interval:0.819-0.881).The cutoff ≥ 60 achieved sensitivity of 65.63% and specificity of 85.63% in discriminating autism children from the general population.Conclusion The results indicate that C_ASRS (2-5 years) could be used as an early level-2 screening tool for autism screening in China and should be further revised for level-1 screening. 展开更多
关键词 AUTISM AUTISM SPECTRUM RATING SCALE Chinese RELIABILITY Validity
Autism spectrum disorders: autistic phenotypes and complicated mechanisms
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作者 Xi-Cheng Zhang Li-Qi Shu +1 位作者 Xing-Sen Zhao Xue-Kun Li 《世界儿科杂志(英文版)》 2019年第1期17-25,共9页
Background Autism spectrum disorder (ASD),a pervasive developmental neurological disorder,is characterized by impairments in social interaction and communication,and stereotyped,repetitive patterns of interests or beh... Background Autism spectrum disorder (ASD),a pervasive developmental neurological disorder,is characterized by impairments in social interaction and communication,and stereotyped,repetitive patterns of interests or behaviors.The mechanism of ASDs is complex,and genetic components and epigenetic modifications play important roles.In this review,we summarized the recent progresses of ASDs focusing on the genetic and epigenetic mechanisms.We also briefly discussed current animal models of ASD and the application of high-throughput sequencing technologies in studying ASD.Data sources Original research articles and literature reviews published in PubMed-indexed journals.Results Individuals with ASDs exhibit a set of phenotypes including neurological alteration.Genetic components including gene mutation,copy-number variations,and epigenetic modifications play important and diverse roles in ASDs.The establishment of animal models and development of new-generation sequencing technologies have contributed to reveal the complicated mechanisms underlying autistic phenotypes.Conclusions Dramatic progress has been made for understanding the roles of genetic and epigenetic components in ASD.Future basic and translational studies should be carried out towards those candidate therapeutic targets. 展开更多
关键词 AUTISM spectrum disorders Genetics EPIGENETICS CNV Next-generation sequencing
Alkyl group functionalization-induced phonon thermal conductivity attenuation in graphene nanoribbons
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作者 王彩云 鲁爽 +1 位作者 于晓东 李海鹏 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期522-526,共5页
We calculated the room-temperature phonon thermal conductivity and phonon spectrum of alkyl group-functionalized zigzag graphene nanoribbons(ZGNRs) with molecular dynamics simulations. The increase in both chain lengt... We calculated the room-temperature phonon thermal conductivity and phonon spectrum of alkyl group-functionalized zigzag graphene nanoribbons(ZGNRs) with molecular dynamics simulations. The increase in both chain length and concentration of alkyl groups caused remarkable reduction of phonon thermal conductivity in functionalized ZGNRs. Phonon spectra analysis showed that functionalization of ZGNR with alkyl functional groups induced phonon–structural defect scattering, thus leading to the reduction of phonon thermal conductivity of ZGNR. Our study showed that surface functionalization is an effective routine to tune the phonon thermal conductivity of GNRs, which is useful in graphene thermal-related applications. 展开更多
关键词 graphene nanoribbons(GNRs) thermal CONDUCTIVITY PHONON spectrum surface FUNCTIONALIZATION molecular dynamics simulations
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