期刊文献+
共找到30,946篇文章
< 1 2 250 >
每页显示 20 50 100
Attribution of psychiatric manifestations to systemic lupus erythematosus in Chinese patients:A retrospective study
1
作者 Wen-Qi Geng Xiao-Xi Yang +3 位作者 Jin-Ya Cao Shang-Zhu Zhang Yi-Nan Jiang Jing Wei 《World Journal of Psychiatry》 2025年第2期76-84,共9页
BACKGROUND Not all neuropsychiatric(NP)manifestations in patients with systemic lupus erythematosus(SLE)are secondary to lupus.The clarification of the cause of NP symptoms influences therapeutic strategies for SLE.AI... BACKGROUND Not all neuropsychiatric(NP)manifestations in patients with systemic lupus erythematosus(SLE)are secondary to lupus.The clarification of the cause of NP symptoms influences therapeutic strategies for SLE.AIM To understand the attribution of psychiatric manifestations in a cohort of Chinese patients with SLE.METHODS This retrospective single-center study analyzed 160 inpatient medical records.Clinical diagnosis,which is considered the gold standard,was used to divide the subjects into a psychiatric SLE(PSLE)group(G1)and a secondary psychiatric symptoms group(G2).Clinical features were compared between these two groups.The sensitivity and specificity of the Italian attribution model were explored.RESULTS A total of 171 psychiatric syndromes were recorded in 138 patients,including 87 cases of acute confusional state,40 cases of cognitive dysfunction,18 cases of psychosis,and 13 cases each of depressive disorder and mania or hypomania.A total of 141(82.5%)syndromes were attributed to SLE.In contrast to G2 patients,G1 patients had higher SLE Disease Activity Index-2000 scores(21 vs 12,P=0.001),a lower prevalence of anti-beta-2-glycoprotein 1 antibodies(8.6%vs 25.9%,P=0.036),and a higher prevalence of anti-ribosomal ribonucleoprotein particle(rRNP)antibodies(39.0%vs 22.2%,P=0.045).The Italian attribution model exhibited a sensitivity of 95.0%and a specificity of 70.0%when the threshold value was set at 7.CONCLUSION Patients with PSLE exhibited increased disease activity.There is a correlation between PSLE and anti-rRNP antibodies.The Italian model effectively assesses multiple psychiatric manifestations in Chinese SLE patients who present with NP symptoms. 展开更多
关键词 Systemic lupus erythematosus Neuropsychiatric systemic lupus erythematosus attribution Italian attribution model Referral consultation
暂未订购
A step-by-step Chebyshev space-time spectral method for force vibration of functionally graded structures
2
作者 Haizhou Liu Yixin Huang Yang Zhao 《Acta Mechanica Sinica》 2025年第4期142-155,共14页
This paper proposes a new step-by-step Chebyshev space-time spectral method to analyze the force vibration of functionally graded material structures.Although traditional space-time spectral methods can reduce the acc... This paper proposes a new step-by-step Chebyshev space-time spectral method to analyze the force vibration of functionally graded material structures.Although traditional space-time spectral methods can reduce the accuracy mismatch between tem-poral low-order finite difference and spatial high-order discre tization,the ir time collocation points must increase dramatically to solve highly oscillatory solutions of structural vibration,which results in a surge in computing time and a decrease in accuracy.To address this problem,we introduced the step-by-step idea in the space-time spectral method.The Chebyshev polynomials and Lagrange's equation were applied to derive discrete spatial goverming equations,and a matrix projection method was used to map the calculation results of prev ious steps as the initial conditions of the subsequent steps.A series of numerical experiments were carried out.The results of the proposed method were compared with those obtained by traditional space-time spectral methods,which showed that higher accuracy could be achieved in a shorter computation time than the latter in highly oscillatory cases. 展开更多
关键词 Functionally graded materials space-time spectral method Step-by-step approach Forced vibration
原文传递
Evapotranspiration and Its Components Partitioning Based on an Improved Hydrological Model:Historical Attributions and Future Projections
3
作者 Hong Du Sidong Zeng +1 位作者 Yongyue Ji Jun Xia 《Journal of Earth Science》 2025年第6期2689-2707,共19页
Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water ... Estimation and attribution of evapotranspiration(ET)and its components under changing environment is still a challenge but is essential for understanding the mechanisms of water and energy transfer for regional water resources management.In this study,an improved hydrological model is developed to estimate evapotranspiration and its components,i.e.,evaporation(E)and transpiration(T)by integrated the advantages of hydrological modeling constrained by water balance and the water-carbon close relationships.Results show that the improved hydrological model could captures ET and its components well in the study region.During the past years,annual ET and E increase obviously about 2.40 and 1.42 mm/a,particularly in spring and summer accounting for 90%.T shows less increasement and mainly increases in spring while it decreases in summer.Precipitation is the dominant factor and contributes 74.1%and 90.0%increases of annual ET and E,while the attribution of T changes is more complex by coupling of the positive effects of precipitation,rising temperature and interactive influences,the negative effects of solar diming and elevated CO_(2).In the future,ET and its components tend to increase under most of the Shared Socioeconomic Pathways(SSP)scenarios except for T decreases under the very high emissions scenario(SSP5-8.5)based on the projections.From seasonal perspective,the changes of ET and the components are mainly in spring and summer accounting for 75%,while more slight changes are found in autumn and winter.This study highlights the effectiveness of estimating ET and its components by improving hydrological models within water-carbon coupling relationships,and more complex mechanisms of transpiration changes than evapotranspiration and evaporation changes under the interactive effects of climate variability and vegetation dynamics.Besides,decision makers should pay attention to the more increases in the undesirable E than desirable T. 展开更多
关键词 EVAPOTRANSPIRATION ET components attribution analysis future projections water resources HYDROGEOLOGY
原文传递
Divergent responses of vegetation productivity to soil moisture and vapor pressure deficit across China:Spatiotemporal patterns and climatic attribution
4
作者 SHI Chengyue ZHOU Yuke +2 位作者 CUI Na NIU Lujia YAO Haijun 《Journal of Geographical Sciences》 2025年第7期1405-1431,共27页
Drought significantly constrains vegetation growth and reduces terrestrial carbon sinks.Currently,the spatiotemporal patterns and mechanisms of the differential impacts of soil and meteorological droughts on vegetatio... Drought significantly constrains vegetation growth and reduces terrestrial carbon sinks.Currently,the spatiotemporal patterns and mechanisms of the differential impacts of soil and meteorological droughts on vegetation productivity remain inadequately understood.In this study,we analyzed soil moisture(SM),vapor pressure deficit(VPD),and gross primary productivity(GPP)to investigate their spatiotemporal patterns and the combined effects on GPP over China.The results revealed that:(1)Soil drought and meteorological drought generally exhibited temporally synchronous trends across China.(2)GPP was predominantly affected by the combined and synchronous effects of both SM and VPD,although their effects displayed directional variability differences in certain regions.(3)SM demonstrated a greater relative importance on GPP than VPD across more than half of the regions in China,whereas deciduous broadleaf forests were the only vegetation type primarily affected by VPD.(4)Under the lag effects,both SM and VPD exhibited bidirectional Granger causality with GPP,with the interaction between VPD and GPP proving more pronounced than that of SM.Our research provides valuable insights into the mechanisms through which SM and VPD influence GPP,contributing to improved predictions vegetation productivity and implementing ecological restoration. 展开更多
关键词 soil moisture vapor pressure deficit gross primary productivity spatiotemporal patterns climatic attribution causal analysis
原文传递
Quasi-Orthogonal Space-Time Coding for Backscatter Communications with Multiple-Antenna Tags
5
作者 Cao Shuiling Wang Gongpu +2 位作者 Gao Jie Kuang Lei Chintha Tellambura 《China Communications》 2025年第7期186-194,共9页
Existing orthogonal space-time block coding(OSTBC)schemes for backscatter communication systems cannot achieve a full transmission code rate when the tag is equipped with more than two antennas.In this paper,we propos... Existing orthogonal space-time block coding(OSTBC)schemes for backscatter communication systems cannot achieve a full transmission code rate when the tag is equipped with more than two antennas.In this paper,we propose a quasi-orthogonal spacetime block code(QOSTBC)that can achieve a full transmission code rate for backscatter communication systems with a four-antenna tag and then extend the scheme to support tags with 2i antennas.Specifically,we first present the system model for the backscatter system.Next,we propose the QOSTBC scheme to encode the tag signals.Then,we provide the corresponding maximum likelihood detection algorithms to recover the tag signals.Finally,simulation results are provided to demonstrate that our proposed QOSTBC scheme and the detection algorithm can achieve a better transmission code rate or symbol error rate performance for backscatter communication systems compared with benchmark schemes. 展开更多
关键词 backscatter communications channel coding Internet of Things(IoT) multiple antennas quasi-orthogonal space-time block code
在线阅读 下载PDF
Attribution of regional Hadley circulation intensity changes in the Northern Hemisphere
6
作者 Yi Zheng Bo Sun +4 位作者 Wanling Li Siyu Zhou Jiarui Cai Huixin Li Shengping He 《Atmospheric and Oceanic Science Letters》 2025年第6期37-42,共6页
The discrepancy in the trends of the global zonal mean(GZM)intensity of the Hadley circulation(HCI)between reanalysis data and model simulations has been a problem for understanding the changes in HCI and the influenc... The discrepancy in the trends of the global zonal mean(GZM)intensity of the Hadley circulation(HCI)between reanalysis data and model simulations has been a problem for understanding the changes in HCI and the influence of external forcings.To understand the reason for this discrepancy,this study investigates the trends of intensity of regional HCI of the Northern Hemisphere over the eastern Pacific(EPA),western Pacific(WPA),Atlantic(ATL),Africa(AFR),the Indian Ocean(IDO),and residual area(RA),based on six reanalysis datasets and 13 CMIP6 models.In reanalysis data,the trends in regional HCI over EPA and ATL(WPA and AFR)contribute to(partially offset)the increasing trend in GZM HCI,while the trends in regional HCI over IDO are different in different reanalysis data.The CMIP6 models skillfully reproduce the trends in regional HCI over EPA,ATL,WPA,and AFR,but simulate notable decreasing trends in regional HCI over IDO,which is a key reason for the opposite trends in GZM HCI between reanalysis data and models.The discrepancy in IDO can be attributed to differences in the simulation of diabatic heating and zonal friction between reanalysis data and models.Optimal fingerprint analysis indicates that anthropogenic(ANT)and non-greenhouse gas(NOGHG)forcings are the dominant drivers of the HCI trends in the EPA and ATL regions.In the WPA(AFR)region,NOGHG(ANT)forcing serves as the primary driver.The findings contribute to improving the representation of regional HCI trends in models and improving the attribution of external forcings. 展开更多
关键词 Hadley circulation intensity attribution External forcing Optimal fingerprint method Kuo–Eliassen equation
在线阅读 下载PDF
Hybrid DF and SIR Forwarding Strategy in Conventional and Distributed Alamouti Space-Time Coded Cooperative Networks
7
作者 Slim Chaoui Omar Alruwaili +1 位作者 Faeiz Alserhani Haifa Harrouch 《Computer Modeling in Engineering & Sciences》 2025年第2期1933-1954,共22页
In this paper,we propose a hybrid decode-and-forward and soft information relaying(HDFSIR)strategy to mitigate error propagation in coded cooperative communications.In the HDFSIR approach,the relay operates in decode-... In this paper,we propose a hybrid decode-and-forward and soft information relaying(HDFSIR)strategy to mitigate error propagation in coded cooperative communications.In the HDFSIR approach,the relay operates in decode-and-forward(DF)mode when it successfully decodes the received message;otherwise,it switches to soft information relaying(SIR)mode.The benefits of the DF and SIR forwarding strategies are combined to achieve better performance than deploying the DF or SIR strategy alone.Closed-form expressions for the outage probability and symbol error rate(SER)are derived for coded cooperative communication with HDFSIR and energy-harvesting relays.Additionally,we introduce a novel normalized log-likelihood-ratio based soft estimation symbol(NL-SES)mapping technique,which enhances soft symbol accuracy for higher-order modulation,and propose a model characterizing the relationship between the estimated complex soft symbol and the actual high-order modulated symbol.Further-more,the hybrid DF-SIR strategy is extended to a distributed Alamouti space-time-coded cooperative network.To evaluate the~performance of the proposed HDFSIR strategy,we implement extensive Monte Carlo simulations under varying channel conditions.Results demonstrate significant improvements with the hybrid technique outperforming individual DF and SIR strategies in both conventional and distributed Alamouti space-time coded cooperative networks.Moreover,at a SER of 10^(-3),the proposed NL-SES mapping demonstrated a 3.5 dB performance gain over the conventional averaging one,highlighting its superior accuracy in estimating soft symbols for quadrature phase-shift keying modulation. 展开更多
关键词 Cooperative communication soft information relaying soft symbols modeling cooperative diversity gain distributed Alamouti space-time code
在线阅读 下载PDF
LUAR:Lightweight and Universal Attribute Revocation Mechanism with SGX Assistance towards Applicable ABE Systems
8
作者 Fei Tang Ping Wang +3 位作者 Jiang Yu Huihui Zhu Mengxue Qin Ling Yang 《Computers, Materials & Continua》 2026年第3期1628-1646,共19页
Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a piv... Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a pivotal role in maintaining security.However,existing key revocation mechanisms face two major challenges:(1)High overhead due to ciphertext and key updates,primarily stemming from the reliance on revocation lists during attribute revocation,which increases computation and communication costs.(2)Limited universality,as many attribute revocation mechanisms are tailored to specific ABE constructions,restricting their broader applicability.To address these challenges,we propose LUAR(Lightweight and Universal Attribute Revocation),a novel revocation mechanism that leverages Intel Software Guard Extensions(SGX)while minimizing its inherent limitations.Given SGX’s constrained memory(≈90 MB in a personal computer)and susceptibility to side-channel attacks,we carefully manage its usage to reduce reliance while mitigating potential collusion risks between cloud service providers and users.To evaluate LUAR’s lightweight and universality,we integrate it with the classic BSW07 scheme,which can be seamlessly replaced with other ABE constructions.Experimental results demonstrate that LUAR enables secure attribute revocation with low computation and communication overhead.The processing time within the SGX environment remains stable at approximately 55 ms,regardless of the complexity of access policies,ensuring no additional storage or computational burden on SGX.Compared to the Hardware-based Revocable Attribute-Based Encryption(HR-ABE)scheme(IEEE S&P 2024),LUAR incurs a slightly higher computational cost within SGX;however,the overall time from initiating a data request to obtaining plaintext is shorter.As access policies grow more complex,LUAR’s advantages become increasingly evident,showcasing its superior efficiency and broader applicability. 展开更多
关键词 attribute-based encryption attribute revocation LIGHTWEIGHT UNIVERSALITY
在线阅读 下载PDF
The validation of quality attributes in Primary Human Hepatocytes Standard
9
作者 Zhaoliang Peng Jiaying Wu +7 位作者 Xi Zhang Xinyang Jia Zhitao Wu Hao Dai Da Huang Xin Cheng Guoyu Pan Ruimin Huang 《Cell Regeneration》 2026年第1期102-113,共12页
Primary human hepatocytes(PHH)are used as the FDA-recognized"gold standard"for liver-related studies in vitro.The world’s first PHH group standard(T/CSCB 0008–2021,CSCB standard)was released by Chinese Soc... Primary human hepatocytes(PHH)are used as the FDA-recognized"gold standard"for liver-related studies in vitro.The world’s first PHH group standard(T/CSCB 0008–2021,CSCB standard)was released by Chinese Society for Cell Biology in 2021.In order to justify this standard,six key quality attributes of ten different batches from commercial PHHs,including cell viability,cell morphology,cell markers,albumin secretion,drug metabolism function and bile secretion,were characterized using the designated test methods in the standard.The PHHs from various batches all exhibited typical hepatocytic morphology,high cell viability,and sufficient albumin secretion;whereas,tremendous variations in cell markers,drug metabolism functions,and bile secretion were unexpectedly detected across the board.Flow cytometric assessment of hepatocyte markers revealed the percentages of ALB^(+)or HNF4A^(+)cells in six batches of PHHs,ranging from 49.4%to 98.9%and from 37.7%to 91.4%,respectively.Single cell transcriptomic analysis also revealed significant cell heterogeneity across the different batches,with the proportions of hepatocytes ranging from 69.2%to 98.9%.Considerable heterogeneity in drug metabolism functions across the batches were also found in substrate clearance rate(SCR)and metabolite formation rate(MFR)for six representative CYP450 enzymes,while the results didn’t influence current SCR attribute of CYP3A4.Metabolic capacity and purity are two independent attributes for PHH.The varied biliary excretion indexes around criteria(30%)indicated heterogeneity of PHH biliary excretion capacity.These results confirmed the robustness of most quality attributes in current CSCB standard,while highlighting the need to refine remaining parameters to enhance its practical applicability. 展开更多
关键词 Primary human hepatocyte Cell quality attribute Hepatocyte marker Single cell transcriptomic analysis Drug metabolism function
暂未订购
Scalable transcoding for video transmission over space-time OFDM systems 被引量:2
10
作者 钱团结 孙军 +2 位作者 解蓉 苏鹏程 王嘉 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期405-410,共6页
A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channe... A new scheme combining a scalable transcoder with space time block codes (STBC) for an orthogonal frequency division multiplexing (OFDM) system is proposed for robust video transmission in dispersive fading channels. The target application for such a scalable transcoder is to provide successful access to the pre-encoded high quality video MPEG-2 from mobile wireless terminals. In the scalable transcoder, besides outputting the MPEG-4 fine granular scalability (FGS) bitstream, both the size of video frames and the bit rate are reduced. And an array processing algorithm of layer interference suppression is used at the receiver which makes the system structure provide different levels of protection to different layers. Furthermore, by considering the important level of scalable bitstream, the different bitstreams can be given different level protection by the system structure and channel coding. With the proposed system, the concurrent large diversity gain characteristic of STBC and alleviation of the frequency-selective fading effect of OFDM can be achieved. The simulation results show that the proposed schemes integrating scalable transcoding can provide a basic quality of video transmission and outperform the conventional single layer transcoding transmitted under the random and bursty error channel conditions. 展开更多
关键词 scalable transcoding DOWN-SAMPLING space-time codes orthogonal frequency division multiplexing
在线阅读 下载PDF
天津市工业部门碳排放强度研究:基于LMDI-Attribution分析方法 被引量:22
11
作者 赵涛 田莉 许宪硕 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2015年第7期40-47,共8页
引入对数平均迪式分解模型及其归因分析(LMDI-Attribution)方法,从细分行业角度对2000-2012年天津市工业部门的碳排放强度变化进行研究,首先对碳排放强度作产业结构、能源强度和排放因子三因素LMDI乘法分解,其后,基于三个分解因素在2000... 引入对数平均迪式分解模型及其归因分析(LMDI-Attribution)方法,从细分行业角度对2000-2012年天津市工业部门的碳排放强度变化进行研究,首先对碳排放强度作产业结构、能源强度和排放因子三因素LMDI乘法分解,其后,基于三个分解因素在2000-2006年和2006-2012年两个时间段对碳排放强度下降的影响效应,对其作归因分析,量化36个细分行业对分解因素影响效应的贡献。得到以下主要结论:天津市工业部门的碳排放强度从2000-2012年累计下降了66.87%,产业结构和能源强度是其下降的主导因素,累计影响值分别为-44.53%和-47.39%,排放因子对其下降起抑制作用,累计影响值为15.39%;产业结构对碳排放强度的影响主要依赖于高耗能行业产值占比的变化,化工行业和黑色金属行业产值的占比越高,产业结构的减排效应越差,因此在调整产业结构时,应大力发展服务业和高新技术产业,严格控制高耗能行业发展;黑色金属行业和非金属矿物制品业是能源强度效应变化的主导行业,由于技术进步和能源效率的提高,黑色金属行业的负值贡献在2006-2012年相对前七年增大了2.56倍,非金属矿物制品业从最大的正值贡献行业转为第二大负值贡献行业,使得2006-2012年能源强度对碳排放强度的拉低影响相对前七年增大了近1倍;排放因子对碳排放强度下降的抑制作用在2006年之后呈现减弱的趋势,主要是因为"十一五"期间化工行业能源结构优化与能源再利用体系的建立,有效抑制了排放因子对碳排放强度的拉升作用。综上可见,黑色金属行业、化工行业和非金属矿物制品业是天津市碳排放强度分解因素变化的主要贡献行业,以这些高耗能行业为主要研究对象,根据行业特点及其所处的发展阶段,严格控制其粗放型发展、鼓励新技术研发、循环利用资源及优化用能结构等措施,针对性的制定节能减排办法,才能在保持经济快速发展的同时做到碳排放强度的降低。 展开更多
关键词 工业 碳排放强度 LMDI-attribution 天津
在线阅读 下载PDF
EM-based detection scheme for differential unitary space-time modulation
12
作者 杜正锋 陈杰 +1 位作者 潘文 高西奇 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期484-488,共5页
The performance loss of an approximately 3 dB signal-to-noise ratio is always paid with conventional differential detection compared to the related coherent detection. A new detection scheme consisting of two steps is... The performance loss of an approximately 3 dB signal-to-noise ratio is always paid with conventional differential detection compared to the related coherent detection. A new detection scheme consisting of two steps is proposed for the differential unitary space-time modulation (DUSTM) system. In the first step, the data sequence is estimated by conventional unitary space-time demodulation (DUSTD) and differentially encoded again to produce an initial estimate of the transmitted symbol stream. In the second step, the initial estimate of the symbol stream is utilized to initialize an expectation maximization (EM)-based iterative detector. In each iteration, the most recent detected symbol stream is employed to estimate the channel, which is then used to implement coherent sequence detection to refine the symbol stream. Simulation results show that the proposed detection scheme performs much better than the conventional DUSTD after several iterations. 展开更多
关键词 unitary space-time modulation differential detection expectation maximization (EM) algorithm
在线阅读 下载PDF
基于space-time的二叉树表示动态环境中的路径规划
13
作者 唐平 何卓华 杨宜民 《计算机工程》 CAS CSCD 北大核心 2002年第5期59-60,74,共3页
研究具有空间和时间的三维动态环境下的机器人路径规划分析了四叉树表示二维空间的搜索算法,在此基础上,提出采space-time,用二叉树表示二维空间的方法时间信息中增加加速度利用二叉树遍历方法和算法设计一个在动态障碍物环境下进行路... 研究具有空间和时间的三维动态环境下的机器人路径规划分析了四叉树表示二维空间的搜索算法,在此基础上,提出采space-time,用二叉树表示二维空间的方法时间信息中增加加速度利用二叉树遍历方法和算法设计一个在动态障碍物环境下进行路径规划的新算法并,,A*,,在足球机器人系统中进行仿真,实现了较好的路径规划。 展开更多
关键词 移动机器人 数据结构 space-time 二叉树 动态环境 路径规划
在线阅读 下载PDF
Design of super-orthogonal space-time trellis codes based on trace criterion
14
作者 耿嘉 曹秀英 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期456-460,共5页
A design of super-orthogonal space-time trellis codes (SOSTTCs) based on the trace criterion (TC) is proposed for improving the design of SOSTTCs. The shortcomings of the rank and determinant criteria based design... A design of super-orthogonal space-time trellis codes (SOSTTCs) based on the trace criterion (TC) is proposed for improving the design of SOSTTCs. The shortcomings of the rank and determinant criteria based design and the advantages of the TC-based design are analyzed. The optimization principle of four factors is presented, which includes the space-time block coding (STBC) scheme, set partitioning, trellis structure, and the assignment of signal subsets and STBC schemes in the trellis. According to this principle, systematical and handcrafted design steps are given in detail. By constellation expansion, the code performance can be further improved. The code design results are given, and the new codes outperform others in the simulation. 展开更多
关键词 super-orthogonal space-time trellis codes trace criterion handcrafted and systematical design
在线阅读 下载PDF
基于LMDI-Attribution的江苏省水足迹效率变化驱动力分析 被引量:1
15
作者 姜翔程 王睿 《资源与产业》 2022年第4期30-41,共12页
在长江经济带各省市中,江苏省水足迹总量和人均量最大,缺水程度最严重,较低的水资源可持续发展能力制约了江苏省经济社会的发展。从水足迹视角,聚焦江苏省水足迹效率变化,分析水足迹效率变化的驱动因素和大小,为江苏省水资源可持续发展... 在长江经济带各省市中,江苏省水足迹总量和人均量最大,缺水程度最严重,较低的水资源可持续发展能力制约了江苏省经济社会的发展。从水足迹视角,聚焦江苏省水足迹效率变化,分析水足迹效率变化的驱动因素和大小,为江苏省水资源可持续发展提出建议。基于2010—2019年江苏省水足迹计算结果,扩展Kaya恒等式构造出驱动水足迹效率变化的实际用水效率、水资源利用技术水平和水足迹结构3个因素,借助LMDI-Attribution模型计算各因素驱动力大小,并得到三大用水部门的具体贡献度。结果表明:研究期间江苏省水足迹效率增长幅度较大,从2010年的32.78元/m~3增加到2019年的88.91元/m~3,增幅为171.25%,其中实际用水效率为水足迹效率变化的最大驱动力,贡献了167%,其次为技术水平,贡献了26.15%;由于农业部门水足迹占比增大,水足迹结构对变化的影响为-21.67%;从用水部门来看,工业部门和生活部门的实际用水效率是最关键的驱动力,分别为91.19%和75.07%,农业部门仅为0.73%;技术水平驱动力中贡献最大的为生活部门的21.40%,其次为工业部门的4.79%,而农业部门为-0.04%;水足迹结构驱动力中仅农业部门是正向的,为0.06%,生活部门为-2.13%,工业部门为-19.60%。建议江苏省建立健全节水型农业体系,提高农业用水效率,降低农业部门水足迹所占比例,保持各用水部门灰水足迹的下降趋势,限制高污染企业的投资建设,支持绿色企业的发展;刺激省内消费需求,不断优化对外贸易结构,提升水资源可持续发展能力。 展开更多
关键词 水足迹 驱动力 LMDI分解 归因分析 江苏省
原文传递
Method of combining space-time block coding with adaptive beamforming
16
作者 沈克勤 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期254-259,共6页
A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then con... A method of space-time block coding (STBC) system based on adaptive beamforming of cyclostationarity signal algorithm is proposed.The method uses cyclostationarity of signals to achieve adaptive beamforming,then constructs a pair of low correlated transmit beams based on beamform estimation of multiple component signals of uplink.Using these two selected transmit beams,signals encoded by STBC are transmitted to achieve diversity gain and beamforming gain at the same time,and increase the signal to noise ratio (SNR) of downlink.With simple computation and fast convergence performance,the proposed scheme is applicable for time division multiple access (TDMA) wireless communication operated in a complex interference environment.Simulation results show that the proposed scheme has better performance than conventional STBC,and can obtain a gain of about 5 dB when the bit error ratio (BER) is 10-4. 展开更多
关键词 space-time coding GAIN adaptive beamforming cyclostationary signal transmit diversity
在线阅读 下载PDF
Distribution of high-risk human papillomavirus genotype prevalence and attribution to cervical precancerous lesions in rural North China 被引量:37
17
作者 Shuang Zhao Xuelian Zhao +5 位作者 Shangying Hu Jessica Lu Xianzhi Duan Xun Zhang Feng Chen Fanghui Zhao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第4期663-672,共10页
Objective: Precise prevention is more desired for cervical cancer due to the huge population, high prevalence of human papillomavirus(HPV) infection in China and the vision of screen-and-treat strategies in low-and mi... Objective: Precise prevention is more desired for cervical cancer due to the huge population, high prevalence of human papillomavirus(HPV) infection in China and the vision of screen-and-treat strategies in low-and middleincome countries(LMICs). Considerations of combining type-specific prevalence and attribution proportion to high-grade cervical intraepithelial neoplasia are informative to more precise and effective region-specific cervical cancer prevention and control programs. The aim of the current study was to determine the genotype distribution of HPV and attribution to cervical precancerous lesions among women from rural areas in North China.Methods: A total of 9,526 women participated in the cervical cancer screening project in rural China. The samples of women who tested positive for HPV were retested with a polymerase chain reaction(PCR)-based HPV genotyping test. The attribution proportion of specific high-risk human papillomavirus(HR-HPV) types for different grades of cervical lesions was calculated by using the type contribution weighting method.Results: A total of 22.2%(2,112/9,526) of women were HR-HPV positive and HPV52(21.7%) was the most common HR-HPV genotype, followed by HPV58(18.2%), HPV53(18.2%) and HPV16(16.2%). The top three genotypes detected in HR-HPV-positive cervical intraepithelial neoplasia(CIN)1 were HPV16(36.7%), HPV58(20.4%), HPV56(15.3%). Among CIN2+, the most frequent genotypes were HPV16(75.6%), HPV52(17.8%),HPV58(16.7%). HPV16, 56, 58, 53, 52, 59, 68, and 18 combined were attributed to 84.17% of all CIN1 lesions,and HPV16, 58, and 52 combined were attributed to 86.98% of all CIN2+ lesions.Conclusions: The prevalence of HR-HPV infection among women from rural areas in North China was high and HPV16, HPV58, HPV52 had paramount attributable fraction in CIN2+. Type-specific HPV prevalence and attribution proportion to cervical precancerous lesions should be taken into consideration in the development of vaccines and strategy for screening in this population. 展开更多
关键词 Human PAPILLOMAVIRUS CERVICAL intraepithelial NEOPLASIA GENOTYPE DISTRIBUTION attribution proportion CERVICAL cancer
暂未订购
Attribution of the Langshan Tectonic Belt: Evidence from zircon U-Pb ages and Hf isotope compositions 被引量:6
18
作者 Chuang Bao Yuelong Chen +1 位作者 Xiangkun Zhu Junxiang Zhao 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第2期539-551,共13页
This study describes a previously unidentified Neoproterozoic mafic dyke emplaced in the northern flank of the Langshan Tectonic Belt. This dyke intruded into the micaquartz schist of the Zhaertaishan Group, and yield... This study describes a previously unidentified Neoproterozoic mafic dyke emplaced in the northern flank of the Langshan Tectonic Belt. This dyke intruded into the micaquartz schist of the Zhaertaishan Group, and yielded an age of 908 ± 8 Ma. The youngest U-Pb ages of micaquartz schist from the Zhaertaishan Group in the Langshan area were 1118 ± 33 Ma,1187 ± 3 Ma and 1189 ± 39 Ma,suggesting that the depositional age of the protolith of the schist was between 908 ± 8 Ma and 1118 ± 33 Ma. In addition, 436 U-Pb age data and 155 Lu-Hf isotopic data from six samples in the Langshan Tectonic Belt and one Permian greywacke from the Wuhai area show distinct differences between the northern and southern flanks of the Main Langshan area. The U-Pb ages of the northern flank are primarily Meso-Neoproterozoic; similar ages have not been identified in the southern flank to date.Moreover, two-stage Hf model ages of the northern flank feature three age peaks at ~900 Ma,~1700 Ma and ~2600 Ma; this differs from Hf model ages of the southern flank, which feature one strong age peak at ~2700 Ma. These results suggest that the northern and southern flanks of the Main Langshan area have different geochronologic characteristics and should be divided further. Based on the U-Pb ages and Hf model ages, the northern and southern flanks of the Main Langshan area are named the North and South Langshan Tectonic Belts. Comparison of the U-Pb age and two-stage Hf model age distributions from the North Langshan Tectonic Belt, South Langshan Tectonic Belt, Alxa Block and the North China Craton(NCC) reveal that the North Langshan Tectonic Belt is similar to the Alxa Block and that the South Langshan Tectonic Belt is similar to the NCC. In addition, the zircon U-Pb age of 860 ±7 Ma commonly observed in the Alxa Block was detected in the Permian greywacke from the Wuhai area of the NCC, which suggests that the amalgamation of the North and South Langshan Tectonic belts(i.e.,the amalgamation of the Alxa Block and the NCC), occurred between Devonian and late Permian. 展开更多
关键词 Langshan TECTONIC BELT attribution Alxa Block North China CRATON U-PB Hf isotopic composition
在线阅读 下载PDF
Attribution retraining group therapy for outpatients with major depression disorder,generalized anxiety disorder,and obsessive-compulsive disorder:a pilot study 被引量:7
19
作者 Chun Wang Jie Zhang +2 位作者 Jijun Li Ning Zhang Yalin Zhang 《The Journal of Biomedical Research》 CAS 2011年第5期348-355,共8页
The aim of this present study is to examine the efficacy of attribution retraining group therapy (ARGT) and to compare the responses of outpatients with major depression disorder (MDD), generalized anxiety disord... The aim of this present study is to examine the efficacy of attribution retraining group therapy (ARGT) and to compare the responses of outpatients with major depression disorder (MDD), generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD). We carried out a prospective uncontrolled intervention study with a 8-weeks of ARGT on sixty three outpatients with MDD, GAD or OCD. Hamilton rating scale for depression, Hamilton rating scale for anxiety, Yale-Brown obsessive-compulsive scale, attribution style questionnaire, self-esteem scale, index of well-being, and social disability screening schedule were administered before and after treatment. Significant improvement in symptoms and psychological and social functions from pre- to posttreatment occurred for all participants. The changes favored MDD patients. Our study suggested that ARGT may improve the symptoms and psychological-social functions of MDD, GAD, and OCD patients. MDD patients showed the best response. 展开更多
关键词 attribution retraining group psychotherapy major depression disorder generalized anxiety disorder obsessive-compulsive disorder
在线阅读 下载PDF
ON MARKOV CHAINS IN SPACE-TIME RANDOM ENVIRONMENTS 被引量:7
20
作者 胡迪鹤 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期1-10,共10页
In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTR... In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTRE(+) by an initial distribution Φ and a random Markov kernel (RMK) p(γ). In Section 3, the authors es-tablish several equivalence theorems on MCSTRE and MCSTRE(+). Finally, the authors give two very important examples of MCMSTRE, the random walk in spce-time random environment and the Markov br... 展开更多
关键词 Random Markov kernel Markov chain in space-time random environemnt random walk in space-time random environment Markov branching chain in space-time random environment
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部