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Hybrid DF and SIR Forwarding Strategy in Conventional and Distributed Alamouti Space-Time Coded Cooperative Networks
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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
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Light induced space-time patterns in a superfluid Fermi gas
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作者 Fang Li Shujin Deng +3 位作者 Liang Zhang Jiahui Xia Licheng Yi Haibin Wu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2021年第9期51-55,共5页
Patterns resulted from modulation instability are ubiquitous and have been extensively studied in optics and Bose-Einstein condensates. However, these patterns have not been realized in ultracold Fermi gases, although... Patterns resulted from modulation instability are ubiquitous and have been extensively studied in optics and Bose-Einstein condensates. However, these patterns have not been realized in ultracold Fermi gases, although there has been considerable theoretical interest in this field. Here we report an experimental observation of space-time patterns in a superfluid Fermi gas excited by red-detuned laser light. Longitudinal spatially fluctuated laser beams induce the spontaneous formation of two different kinds of patterns. For strongly interacting Fermi gas, the induced patterns accompanied by phonon excitations demonstrate a striking"X"-type dispersion relation between frequency and wavevector. Then, the propagation of such patterns in the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer crossover is investigated, which is related to the speed of sound and agrees well with theoretical calculations. The observed patterns in noninteracting Fermi gases are stationary without phonon excitations and show a much longer lifetime. 展开更多
关键词 modulation instability phonon excitations space-time patterns
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Space-time Distribution Pattern of Monochamus alternatus in Wanding City
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作者 熊忠平 涂玉 司徒英贤 《Plant Diseases and Pests》 CAS 2010年第2期35-37,共3页
[Objective] The purpose was to study space-time distribution pattern of Monochamus alternatus in Wanding City. [Method] Based on data about insect situation supervision on M. alternatus in Wanding City, using related ... [Objective] The purpose was to study space-time distribution pattern of Monochamus alternatus in Wanding City. [Method] Based on data about insect situation supervision on M. alternatus in Wanding City, using related mathematical statistics methods including linear regression analysis and spatial distribution pattern of insect population, the relationship between emergence period, emergence quantity and temperature of M. alternatus adult, spatial distribution pattern of adults and their life history were studied. [Result] M. alternatus occurred one generation per year in Wanding city, June was the maximum period of adults, which was also the key trapping period. Spatial distribution of M. alternatus was accumulative. [Conclusion] This study provided theoretical basis for further control on M. alternatus for forestry bureau of Wanding City. 展开更多
关键词 Wanding Monochamus alternatus Life history Spatial distribution pattern
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ESTIMATION OF AVERAGE DIFFERENTIAL ENTROPY FOR A STATIONARY ERGODIC SPACE-TIME RANDOM FIELD ON A BOUNDED AREA
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作者 Zhanjie SONG Jiaxing ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1984-1996,共13页
In this paper,we mainly discuss a discrete estimation of the average differential entropy for a continuous time-stationary ergodic space-time random field.By estimating the probability value of a time-stationary rando... In this paper,we mainly discuss a discrete estimation of the average differential entropy for a continuous time-stationary ergodic space-time random field.By estimating the probability value of a time-stationary random field in a small range,we give an entropy estimation and obtain the average entropy estimation formula in a certain bounded space region.It can be proven that the estimation of the average differential entropy converges to the theoretical value with a probability of 1.In addition,we also conducted numerical experiments for different parameters to verify the convergence result obtained in the theoretical proofs. 展开更多
关键词 differential entropy STATIONARY ERGODICITY space-time random field time series
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Robust Space-Time Adaptive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum
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作者 Xiaojing Su Da Xu +1 位作者 Dongsheng Zhu Zhixun Ma 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期65-74,共10页
Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,ca... Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak targets.However,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the algorithm.In this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and P-RAO-DP-TBD.The simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities. 展开更多
关键词 space-time adaptive detection track before detect ROBUSTNESS persymmetric property symmetric spectrum AMF test RAO test
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Space-time analysis of the changing patterns of population pressure on the ecological environment in China 被引量:1
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作者 Dongqi Sun Jinliang Jiang +2 位作者 Jianbin Xu Liang Zhou Yi Hu 《Chinese Journal of Population,Resources and Environment》 2015年第4期341-348,共8页
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat... This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality. 展开更多
关键词 Chinese POPULATION ECO-ENVIRONMENT ECO-ENVIRONMENTAL pressure CHANGING TREND space-time analysis
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Curved Space-Time at the Planck Scale
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期167-179,共13页
This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the me... This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the metric tensor, is considered to be made up of a dynamic lattice of extremely small, localized fields that form a perfectly elastic Lorentz symmetric space-time at the global (macroscopic) scale. This theoretical model of space-time at the Planck scale leads to a somewhat surprising result in which matter waves in curved space-time radiate thermal gravitational energy, as well as an equally intriguing relationship for the anomalous dispersion of light in a gravitational field. 展开更多
关键词 Schwarzschild space-time Continuum Mechanics Planck Lattice Gravitational Radiation
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Virtually coupled train set control subject to space-time separation:A distributed economic MPC approach with emergency braking configuration
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作者 Xiaolin Luo Tao Tang +1 位作者 Le Wang Hongjie Liu 《High-Speed Railway》 2024年第3期143-152,共10页
The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calcula... The emerging virtual coupling technology aims to operate multiple train units in a Virtually Coupled Train Set(VCTS)at a minimal but safe distance.To guarantee collision avoidance,the safety distance should be calculated using the state-of-the-art space-time separation principle that separates the Emergency Braking(EB)trajectories of two successive units during the whole EB process.In this case,the minimal safety distance is usually numerically calculated without an analytic formulation.Thus,the constrained VCTS control problem is hard to address with space-time separation,which is still a gap in the existing literature.To solve this problem,we propose a Distributed Economic Model Predictive Control(DEMPC)approach with computation efficiency and theoretical guarantee.Specifically,to alleviate the computation burden,we transform implicit safety constraints into explicitly linear ones,such that the optimal control problem in DEMPC is a quadratic programming problem that can be solved efficiently.For theoretical analysis,sufficient conditions are derived to guarantee the recursive feasibility and stability of DEMPC,employing compatibility constraints,tube techniques and terminal ingredient tuning.Moreover,we extend our approach with globally optimal and distributed online EB configuration methods to shorten the minimal distance among VCTS.Finally,experimental results demonstrate the performance and advantages of the proposed approaches. 展开更多
关键词 Virtually coupled train set space-time separation Economic model predictive control Distributed model predictive control Emergency braking configuration
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Space-time Dynamics of Dendroctonus valens Population in China and Spatial Sampling Technique based on Its Spatial Distribution Pattern
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作者 Pan Jie Wang Tao +2 位作者 Zong Shixiang Wen Junbao Luo Youqing 《Plant Diseases and Pests》 CAS 2015年第3期20-24,38,共6页
Red turpentine beetle (RTB), Dendroctongs valens LeConte, is a destructive forest invasive species in China, it mainly attacks Pings tabuliformis and P. bungeana. So far it has spread rapidly to the provinces of Sha... Red turpentine beetle (RTB), Dendroctongs valens LeConte, is a destructive forest invasive species in China, it mainly attacks Pings tabuliformis and P. bungeana. So far it has spread rapidly to the provinces of Shanxi, Hebei, Henan, Shanxi and Beijing since its first outbreak in Shanxi Province in 1998, and has caused extensive tree mortality. Space-time dynamics of D. valens population and spatial sampling technique based on its spatial distribution pattern were ana- lyzed using geostatistical methods in the pure P. tabuliforis forests and mixedwood stands which were at different damage levels. According to the spatial distribu- tion of D. valeas population, the specific spatial sampling technique was also studied, and then was compared with traditional sampling technique. The spatial sam- piing technique combined with sampling theory and the biological characteristics of D. valens population, which not only could calcnlate the error of the sampling, but also could discuss the optimal sampling number and the optimum size of plot according to different damage levels and different stand types. This helps to explain population expansion and colonization mechanism of D. valens, and to provide a good reference for adopting snitable control measures. 展开更多
关键词 Dendroctonus valens Spatial distribution pattern GEOSTATISTICS space-time dynamics Spatial sampling
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Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)
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作者 Peh Keong TEH Seyed ZEKAVAT 《International Journal of Communications, Network and System Sciences》 2009年第6期469-479,共11页
In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (a... In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas. 展开更多
关键词 Antenna Array Beam pattern SWEEPING Transmit Diversity space-time Block CODES and space-time TRELLIS Coding
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Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study
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作者 Bijnya Birajita Panda Chitaranjan Mishra +3 位作者 Bhagabat Nayak Avik Kumar Roy Logesh Balakrishnan Priyadarshini Mishra 《World Journal of Clinical Cases》 SCIE 2025年第1期29-37,共9页
BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have ... BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no research.AIM To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic intervention.METHODS A cross-sectional survey was disseminated among ophthalmologists all over India.The survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up patterns.RESULTS A total of 180 ophthalmologists responded to the survey.Most practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was advised.The most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid surgeries.Sixty-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease patients.CONCLUSION Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular conditions.Many ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract surgery.Eyelid conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections. 展开更多
关键词 Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns SURVEY
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Quality of Life and Long-Term Complications of Diabetic Patients in Bangladesh: Does Treatment Pattern Differ the Quality of Life of Diabetic Patients?
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作者 A. B. M. Nahid Hasan Abu Saleh +7 位作者 Mst. Roni Khatun Md. Sharif Uddin Miah Taufikul Islam Mst. Tasnima Akter Shikha G. M. Yousuf Mahadi Prosenjit Basak Golam Rabby Mst. Rokshana Rabeya 《Journal of Diabetes Mellitus》 2025年第1期71-91,共21页
Background: Diabetes Mellitus (DM) is a growing health issue in Bangladesh, with significant complications affecting the quality of life (QoL). This study aims to assess long-term complications, treatment patterns, an... Background: Diabetes Mellitus (DM) is a growing health issue in Bangladesh, with significant complications affecting the quality of life (QoL). This study aims to assess long-term complications, treatment patterns, and QoL of diabetic patients during COVID-19. Methods: A cross-sectional study was conducted on 385 diabetic patients (aged 18-80) from tertiary hospitals in Dhaka and Mymensingh between May and October 2022. Data were collected via a semi-structured questionnaire on sociodemographics, complications, treatment patterns, and QoL (SF-12 scale). Chi-square tests, ANOVA, and linear regression were used for inferential analysis. Results: The sample predominantly included middle-aged males (41 - 55 years) with type 2 diabetes. Diabetic retinopathy (34.5%), polyneuropathy (32.2%), and hypertension (52.3%) were the most common complications. Oral medications were used by 59.7% of patients, with 29.1% on insulin. Chi-square analysis showed a significant association between treatment adherence and complications (p β = 0.45, p Conclusion: Complications in diabetic patients significantly affect QoL in Bangladesh. Treatment adherence, especially with oral medications, positively impacts QoL. There is a need for improved access to diabetes care to manage complications and enhance the overall well-being of diabetic patients. 展开更多
关键词 Diabetes Mellitus Quality of Life Long-Term Complications Treatment patterns BANGLADESH
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Quantitative Assessment of Generative Large Language Models on Design Pattern Application
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作者 Dae-Kyoo Kim 《Computers, Materials & Continua》 2025年第3期3843-3872,共30页
Design patterns offer reusable solutions for common software issues,enhancing quality.The advent of generative large language models(LLMs)marks progress in software development,but their efficacy in applying design pa... Design patterns offer reusable solutions for common software issues,enhancing quality.The advent of generative large language models(LLMs)marks progress in software development,but their efficacy in applying design patterns is not fully assessed.The recent introduction of generative large language models(LLMs)like ChatGPT and CoPilot has demonstrated significant promise in software development.They assist with a variety of tasks including code generation,modeling,bug fixing,and testing,leading to enhanced efficiency and productivity.Although initial uses of these LLMs have had a positive effect on software development,their potential influence on the application of design patterns remains unexplored.This study introduces a method to quantify LLMs’ability to implement design patterns,using Role-Based Metamodeling Language(RBML)for a rigorous specification of the pattern’s problem,solution,and transformation rules.The method evaluates the pattern applicability of a software application using the pattern’s problem specification.If deemed applicable,the application is input to the LLM for pattern application.The resulting application is assessed for conformance to the pattern’s solution specification and for completeness against the pattern’s transformation rules.Evaluating the method with ChatGPT 4 across three applications reveals ChatGPT’s high proficiency,achieving averages of 98%in conformance and 87%in completeness,thereby demonstrating the effectiveness of the method.Using RBML,this study confirms that LLMs,specifically ChatGPT 4,have great potential in effective and efficient application of design patterns with high conformance and completeness.This opens avenues for further integrating LLMs into complex software engineering processes. 展开更多
关键词 Design patterns large language models pattern application pattern-based refactoring quantitative assessment
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Influence of the Scandinavian Pattern on Summer Extreme Precipitation over the Eastern Slopes of the Tibetan Plateau
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作者 Quanliang CHEN Ziqi ZHANG +2 位作者 Yang LI Yujing LIAO Dandan DONG 《Advances in Atmospheric Sciences》 2025年第3期438-452,共15页
The Scandinavian(SCA)pattern is an important climate signal in regulating the variability of summer extreme precipitation(SEP)over the eastern slopes of the Tibetan Plateau(ESTP).There is a strong negative correlation... The Scandinavian(SCA)pattern is an important climate signal in regulating the variability of summer extreme precipitation(SEP)over the eastern slopes of the Tibetan Plateau(ESTP).There is a strong negative correlation between the SCA pattern and SEP over the ESTP,with a correlation coefficient of-0.57.Moisture budget analysis showed that the dynamic component anomalies of both the zonal and vertical moisture advection induced by the SCA pattern play the dominant roles in extreme precipitation variability over the ESTP.These anomalies are solely linked to variations in zonal wind and vertical velocity.The anomalies of the SCA pattern propagate downstream through Rossby waves,leading to the formation of cyclonic circulations over northern East Asia and the Iranian Plateau.The westerlies on the southern side of these cyclonic circulations play a crucial role in influencing the development of significant anomalous westerlies over the ESTP.The anomalous westerlies bring climatologically moist air from the Tibetan Plateau(TP)to the ESTP,resulting in positive zonal moisture advection anomalies over the area.Furthermore,these anomalous westerlies transport climatologically warm air from the TP to the ESTP,leading to significant warm advection anomalies and vertical upward motion anomalies over the ESTP.The upward motion carries lower-tropospheric moisture upward,resulting in positive vertical moisture advection anomalies over the ESTP.The combination of these positive zonal and vertical moisture advection anomalies eventually leads to excessive SEP. 展开更多
关键词 atmospheric circulation extreme precipitation Scandinavian pattern moisture budget
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Spatiotemporal patterns and spatial dislocation with economic level of China’s ecological resilience
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作者 Zedong Yang Hui Sun +1 位作者 Xuechao Xia Xuefeng Zhang 《Chinese Journal of Population,Resources and Environment》 2025年第1期40-48,共9页
Ensuring a harmonious coexistence between man and nature is crucial for China’s economic and social development.However,with increasing industrialization and urbanization,there is a growing mismatch between China’s ... Ensuring a harmonious coexistence between man and nature is crucial for China’s economic and social development.However,with increasing industrialization and urbanization,there is a growing mismatch between China’s ecological resilience(ER)and economic level(EL)of development,which poses a notable social threat.Currently,the link between ER and EL in China remains unclear,especially in terms of spatial dislocation(SD),referring to the disconnect between the locations where environmental impacts occur and those where economic benefits or activities are concentrated.Therefore,this paper aims to provide theoretical support and an empirical basis for policy-based solutions to address this gap.Based on the SD theory,this study systematically discusses the temporal changes,spatial patterns,and SD characteristics of China’s ER and EL using spatial auto-correlation and barycentric analysis to analyze data from 30 provinces covering the period 2011-2021.The key results are as follows.China’s ER shows a general trend of growth;however,its distribution is uneven.The spatial pattern generally decreases from the southeastern coastal provinces to the northwest.Moreover,a gradually increasing positive correlation is observed between the ER and EL,but this correlation varies by region,with some showing regional linkages and others developing independently.Finally,the dislocation index of ER and EL presents divergent results based on region-the eastern and central regions primarily show a high level of dislocation,whereas the western and northeastern regions show a low level of dislocation.The results provide a comprehensive overview of the spatiotemporal patterns in the association between ER and EL in China.The results emphasize that to balance sustainable regional development and ecological governance,a region-specific approach must be employed,prioritizing innovation-driven strategies for high ER in more developed regions and market-oriented strategies in less developed regions. 展开更多
关键词 Ecological resilience Economic level Spatiotemporal pattern Spatial dislocation
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Spatiotemporal distribution patterns of macrobenthic communities and their relationship with environmental factors in the Shengsi Archipelago(Zhejiang,China)
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作者 Lingxiang Jin Yibo Liao +6 位作者 Peisong Yu Yanbin Tang Qinghe Liu Rongliang Zhang Lu Shou Jiangning Zeng Quanzhen Chen 《Acta Oceanologica Sinica》 2025年第1期113-126,I0001-I0011,共25页
Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced b... Macrobenthic organisms are commonly employed as biomonitors for environmental risk assessment.In this study,we aimed to investigate the spatial and temporal patterns of the macrobenthic community,which is influenced by environmental factors of sediments and bottom water layer.We sampled a total of 12,11,10,and 11 stations in the Shengsi Archipelago during June 2010,August 2010,November 2020,and April 2021 respectively.A total of 124 species of macrobenthos were identified,with polychaetes being the dominant group.The abundance,biomass,and diversity indices exhibited no significant temporal differences.Similarly,biodiversity did not exhibit a clear spatial gradient,likely due to the small study area and the absence of significant differences in key factors such as depth.However,the stations with the lowest biodiversity values consistently appeared in the southwest region,possibly due to the impact of human activities.Significant differences in the macrobenthic community were observed between all months except between June and August,and mollusk Endopleura lubrica and polychaete Sigambra hanaokai were important contributors to these differences according to the results of the Similarity Percentages analysis.Suspended particulate matter(SPM)was identified as the primary driving factors of macrobenthic variability.In summary,the community structure underwent temporal changes influenced by complex current patterns,while biodiversity remained relatively stable.This study contributes to our understanding of the key environmental factors affecting macrobenthic communities and biodiversity.It also provides valuable data support for the long-term monitoring of macrobenthos and the environment in the Shengsi Archipelago. 展开更多
关键词 macrobenthic community Shengsi Archipelago distribution pattern BIODIVERSITY environmental factors
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End-to-End Audio Pattern Recognition Network for Overcoming Feature Limitations in Human-Machine Interaction
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作者 Zijian Sun Yaqian Li +2 位作者 Haoran Liu Haibin Li Wenming Zhang 《Computers, Materials & Continua》 2025年第5期3187-3210,共24页
In recent years,audio pattern recognition has emerged as a key area of research,driven by its applications in human-computer interaction,robotics,and healthcare.Traditional methods,which rely heavily on handcrafted fe... In recent years,audio pattern recognition has emerged as a key area of research,driven by its applications in human-computer interaction,robotics,and healthcare.Traditional methods,which rely heavily on handcrafted features such asMel filters,often suffer frominformation loss and limited feature representation capabilities.To address these limitations,this study proposes an innovative end-to-end audio pattern recognition framework that directly processes raw audio signals,preserving original information and extracting effective classification features.The proposed framework utilizes a dual-branch architecture:a global refinement module that retains channel and temporal details and a multi-scale embedding module that captures high-level semantic information.Additionally,a guided fusion module integrates complementary features from both branches,ensuring a comprehensive representation of audio data.Specifically,the multi-scale audio context embedding module is designed to effectively extract spatiotemporal dependencies,while the global refinement module aggregates multi-scale channel and temporal cues for enhanced modeling.The guided fusion module leverages these features to achieve efficient integration of complementary information,resulting in improved classification accuracy.Experimental results demonstrate the model’s superior performance on multiple datasets,including ESC-50,UrbanSound8K,RAVDESS,and CREMA-D,with classification accuracies of 93.25%,90.91%,92.36%,and 70.50%,respectively.These results highlight the robustness and effectiveness of the proposed framework,which significantly outperforms existing approaches.By addressing critical challenges such as information loss and limited feature representation,thiswork provides newinsights and methodologies for advancing audio classification and multimodal interaction systems. 展开更多
关键词 Audio pattern recognition raw audio end-to-end network feature fusion
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Effects of dietary Lactobacillus postbiotics and bacitracin on the modulation of mucosaassociated microbiota and pattern recognition receptors affecting immunocompetence of jejunal mucosa in pigs challenged with enterotoxigenic F18^(+)Escherichia coli
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作者 Marcos Elias Duarte Zixiao Deng Sung Woo Kim 《Journal of Animal Science and Biotechnology》 2025年第1期282-299,共18页
Background Enterotoxigenic Escherichia coli(E.coli)is a threat to humans and animals that causes intestinal dis-orders.Antimicrobial resistance has urged alternatives,including Lactobacillus postbiotics,to mitigate th... Background Enterotoxigenic Escherichia coli(E.coli)is a threat to humans and animals that causes intestinal dis-orders.Antimicrobial resistance has urged alternatives,including Lactobacillus postbiotics,to mitigate the effects of enterotoxigenic E.coli.Methods Forty-eight newly weaned pigs were allotted to NC:no challenge/no supplement;PC:F18^(+)E.coli chal-lenge/no supplement;ATB:F18^(+)E.coli challenge/bacitracin;and LPB:F18^(+)E.coli challenge/postbiotics and fed diets for 28 d.On d 7,pigs were orally inoculated withF18^(+)E.coli.At d 28,the mucosa-associated microbiota,immune and oxidative stress status,intestinal morphology,the gene expression of pattern recognition receptors(PRR),and intestinal barrier function were measured.Data were analyzed using the MIXED procedure in SAS 9.4.Results PC increased(P<0.05)Helicobacter mastomyrinus whereas reduced(P<0.05)Prevotella copri and P.ster-corea compared to NC.The LPB increased(P<0.05)P.stercorea and Dialister succinatiphilus compared with PC.The ATB increased(P<0.05)Propionibacterium acnes,Corynebacterium glutamicum,and Sphingomonas pseudosanguinis compared to PC.The PC tended to reduce(P=0.054)PGLYRP4 and increased(P<0.05)TLR4,CD14,MDA,and crypt cell proliferation compared with NC.The ATB reduced(P<0.05)NOD1 compared with PC.The LPB increased(P<0.05)PGLYRP4,and interferon-γand reduced(P<0.05)NOD1 compared with PC.The ATB and LPB reduced(P<0.05)TNF-αand MDA compared with PC.Conclusions TheF18^(+)E.coli challenge compromised intestinal health.Bacitracin increased beneficial bacteria show-ing a trend towards increasing the intestinal barrier function,possibly by reducing the expression of PRR genes.Lac-tobacillus postbiotics enhanced the immunocompetence of nursery pigs by increasing the expression of interferon-γand PGLYRP4,and by reducing TLR4,NOD1,and CD14. 展开更多
关键词 Escherichia coli IMMUNOCOMPETENCE Intestinal health pattern recognition receptors PIGS
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Research on the Evolution of the Spatiotemporal Patterns and Influencing Factors of China’s Agricultural Green Resilience
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作者 Chen Yihui Li Minjie 《Contemporary Social Sciences》 2025年第1期15-30,共16页
This paper created an evaluation index system for agricultural green resilience,consisting of five dimensions:resistibility,recoverability,adaptability,innovatability,and reconstructability.We used the entropy method ... This paper created an evaluation index system for agricultural green resilience,consisting of five dimensions:resistibility,recoverability,adaptability,innovatability,and reconstructability.We used the entropy method to measure the agricultural green resilience levels of 30 provinces(municipalities/autonomous regions)in China from 2007 to 2021 and employed spatial Markov chains and geographic detectors to reveal the dynamics and evolution of the patterns and influencing factors of the agricultural green resilience.The study shows that the level of agricultural green resilience in China displayed a slight upward trend from 2007 to 2021,but the overall level remained low.Spatially,a distribution pattern of“eastern China>central China>northeastern China>western China”was observed.The transfer process for agricultural green resilience exhibited a“path dependence”characteristic that maintained its initial state,while it also showed a“trickle-down effect.”This means that the regions adjacent to provinces(municipalities/autonomous regions)with higher levels of agricultural green resilience tend to have an increased probability of an upward movement in their ranking.However,such movements are not leapfrogging and only occur at the adjacent levels.The spatial differentiations in the agricultural green resilience levels are primarily driven by the technological innovation capacity and market maturity,with interactions between these factors exhibiting both dual-factor enhancements and nonlinear enhancements.Accordingly,efforts should be made to strengthen support for the less-developed regions,increase research and development investment in the agricultural sector,and improve the market systems for agricultural products to enhance agricultural green resilience. 展开更多
关键词 AGRICULTURE green resilience spatiotemporal patterns spatial Markov chains geographic detector
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An Investigation into Dust Migration Patterns in Small-Section Tunnels and Large Steep-Sloped Inclined Shafts
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作者 Baoli Zang Liyang Shao +2 位作者 Yang Li Hao Ran Liangwen Wei 《Fluid Dynamics & Materials Processing》 2025年第3期555-571,共17页
This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gatheri... This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gathering and transmission trunk line project in the Weiyuan and Luzhou blocks.To gain deeper insights into dust migration patterns,numerical simulations were conducted.The study further analyzed dust migration behavior in small-section tunnels and large steep-sloped shafts,taking into account various factors such as ventilation distance,tunnel slope,and section size.The results indicate that optimal ventilation occurs at distances of 15 and 13 m.Additionally,dust concentration was notably lower when the tunnel slope was 0°,suggesting that a flat slope is more advantageous for construction projects where the outlet wind speed remains constant.Moreover,as the tunnel’s cross-sectional size increases,dust concentration decreases significantly,further underscoring the benefits of larger tunnel sections in mitigating dust accumulation. 展开更多
关键词 Small cross-section tunnels tunnel ventilation dust movement patterns
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