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Spatio-temporal Evolution and Optimization of Landscape Ecological Risk in Karst Mountainous Areas
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作者 Fangfang DENG Zhongfa ZHOU +4 位作者 Denghong HUANG Yang ZHANG Fuxianmei ZHANG Shuanglong DU Yue YANG 《Meteorological and Environmental Research》 2024年第1期16-26,共11页
[Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore ... [Objective]The ecological vulnerability and landscape ecological risk of karst mountainous areas have increased as a result of enhanced disturbance of natural resources by human activities.This paper aimed to explore the characteristics of ecological risk evolution under different landscape patterns in the region,with a view to providing reference for land classification protection,sustainable use of resources and regional ecological risk optimization in karst mountainous areas.[Method]Taking Huangping County,a typical karst mountainous area,as an example,eight evaluation factors of natural and landscape patterns were selected to construct a landscape ecological risk evaluation model,to quantitatively explore the spatio-temporal evolution of landscape ecological risk and the trend of risk level transfer in the study area from^(2)010-2018,and to reveal the complex relationship between ecological risk and topography in karst mountainous areas.[Result]①From 2010 to 2018,land use types changed to different degrees,with the most amount of woodland transferred out(1627.37 hm^(2))and the most amount of construction land transferred in(1303.93 hm^(2));a total of 3552.31 hm^(2) of land was transferred,with a change ratio of 2.13%,and there was a significant conversion between construction land,arable land,and woodland.②From 2010 to 2018,the landscape ecological risk in the study area changed significantly,and the landscape ecological risk index decreased from 0.3441 to 0.1733,showing an upward and then downward trend;the landscape ecological risk of the whole region was dominated by low-risk and lower-risk zones,and the ecological risk level generally shifted from a high level to a low level,and the ecological environment was improved.③There was a negative correlation between ecological risk and topographic position,and high-risk zones were mainly distributed among low topographic zones;with the change of time,the advantage of risk level for the selection of topography was gradually weakened,and the influence of anthropogenic factors on the ecological risk of the landscape was becoming more and more prominent.[Conclusion]This paper can provide theoretical basis for land use optimization and ecological protection in karst mountainous areas. 展开更多
关键词 Karst mountainous area Landscape pattern Landscape ecological risk index Terrain distribution index
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Optimizing Big Data Retrieval and Job Scheduling Using Deep Learning Approaches
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作者 Bao Rong Chang Hsiu-Fen Tsai Yu-Chieh Lin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期783-815,共33页
Big data analytics in business intelligence do not provide effective data retrieval methods and job scheduling that will cause execution inefficiency and low system throughput.This paper aims to enhance the capability... Big data analytics in business intelligence do not provide effective data retrieval methods and job scheduling that will cause execution inefficiency and low system throughput.This paper aims to enhance the capability of data retrieval and job scheduling to speed up the operation of big data analytics to overcome inefficiency and low throughput problems.First,integrating stacked sparse autoencoder and Elasticsearch indexing explored fast data searching and distributed indexing,which reduces the search scope of the database and dramatically speeds up data searching.Next,exploiting a deep neural network to predict the approximate execution time of a job gives prioritized job scheduling based on the shortest job first,which reduces the average waiting time of job execution.As a result,the proposed data retrieval approach outperforms the previous method using a deep autoencoder and Solr indexing,significantly improving the speed of data retrieval up to 53%and increasing system throughput by 53%.On the other hand,the proposed job scheduling algorithmdefeats both first-in-first-out andmemory-sensitive heterogeneous early finish time scheduling algorithms,effectively shortening the average waiting time up to 5%and average weighted turnaround time by 19%,respectively. 展开更多
关键词 Stacked sparse autoencoder Elasticsearch distributed indexing data retrieval deep neural network job scheduling
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Effect of terrain on landscape patterns and ecological effects by a gradient-based RS and GIS analysis 被引量:5
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作者 Wenfeng Gong Haibo Wang +2 位作者 Xiaofeng Wang Wenyi Fan Philip Stott 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期1061-1072,共12页
Terrain is an important environment factor that plays a vital role in human development by influencing the spatial layout of land use patterns. The terrain niche index, combined with slope and elevation, can comprehen... Terrain is an important environment factor that plays a vital role in human development by influencing the spatial layout of land use patterns. The terrain niche index, combined with slope and elevation, can comprehensively present detailed information about spatial differences in terrain and is superior to single terrain factors. We applied remote sensing and geographical information system to terrain gradient, used the non-dimensional distribution index to examine spatial distribution characteristics of various landscape types, and analyzed the ecological effects of landscape were quantitatively on terrain gradients. Eco-environment quality (EEQ) was evaluated using the forestry operation area as the evaluation unit. The spatial distributions in various landscapes were significantly influenced by terrain factors, especially by bodies of water, cropland and residential land. The spatial distribution varied greatly in different terrain gradients for similar landscape types. The areas associated with good, intermediate and poor EEQ were occupied primarily by natural landscape, semi-natural and largely artificial landscapes, respectively. 展开更多
关键词 Terrain niche index Spatial distribution characteristics Distribution index Eco-environment quality
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Improvement on the Effectiveness of Marine Stock Enhancement in the Artificial Reef Area by a New Cage-Based Release Technique 被引量:1
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作者 ZHANG Junbo HE Yufeng +6 位作者 GUO Zhixing JI Shuheng ZHANG Shuo TANG Yanli SHENG Huaxiang WAN Rong KITAZAWA Daisuke 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第4期992-998,共7页
The release technique,affecting the survival rate of fish species released for stock enhancement,plays a vital role in the effectiveness of the enhancement.In order to improve the probability of released fish settling... The release technique,affecting the survival rate of fish species released for stock enhancement,plays a vital role in the effectiveness of the enhancement.In order to improve the probability of released fish settling down to bottom,a new cage-based release technique was designed and tested via a water tank with artificial reef models.Two coral reef fish species,Sebastes schlegelii and Paralichthys olivaceus were assessed using this technique.Fish behavior and distribution in water tank were recorded and compared with the traditional release release techniques.Results showed that in the case of cage-based release technique:1)when the release process is just finished,the distribution index(DI)of juveniles S.schlegelii and P.olivaceus were 97.8%and 98.9%at reef area,40%and 71.1%at release point,respectively,which was higher than those using two alternative techniques;2)its impact duration was less than that in the other two conditions,where the DI within 4 hours was higher after releasing,especially for S.schiegelii.These findings indicated that the new cage-based technique could release the fish into the specified location,and has a potential to mitigate the stress reaction of fish caused by releasing process. 展开更多
关键词 release technique cage-based device distribution patterns distribution index stock enhancement
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Fabrication of long-period fiber gratings by CO_2 laser in fiber under tension 被引量:1
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作者 刘云启 涂文涛 +1 位作者 杨丹 王廷云 《Journal of Shanghai University(English Edition)》 CAS 2011年第1期1-6,共6页
We demonstrate experimentally fabrication of CO2 laser written long-period fiber gratings (LPFGs) in single-mode fiber (SMF) under tension. New transmission dips can be generated due to the frozen-in stress in the... We demonstrate experimentally fabrication of CO2 laser written long-period fiber gratings (LPFGs) in single-mode fiber (SMF) under tension. New transmission dips can be generated due to the frozen-in stress in the fiber under tension. Dynamics analysis of laser writing process is performed to study the mechanism of the grating inscription. Experimental results show that the wavelength shift of new generated resonance dips can shift towards the longer or shorter wavelength with the increase of laser scanning cycles for gratings with different pitches. 展开更多
关键词 long-period fiber grating (LPFG) frozen-in viscoelasticity writing dynamics analysis asymmetric index distribution
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Quantitative Analysis on Distribution of Modifier in Microstructure of SBS Modifi ed Asphalt 被引量:1
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作者 殷巍 杨群 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期740-744,共5页
A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the prepar... A method was developed to make a quantitative analysis of the microstructure of asphalt modified with styrene-butadiene-styrene block(SBS) copolymer. Moreover, both mixed and branched SBS were employed in the preparation of modified asphalt. By sampling specimens from the top, middle, and bottom, a number of microscope slides were made and 400 times micro images were gained. Binarized with the software of MATLAB, the images then went to the process of distribution test, when four typical distributions were employed to investigate the distribution of modifi er spread in asphalt. The distribution characteristic and its parameter were both found. The results show that asphalt phase clearly obeys Poisson distribution, and its parameter, λ, is bond up with the condition SBS performs in. Based on this parameter, indexes can be set up to evaluate the structure of the mixture and its performance as well. Compared with that modifi ed with mixed SBS, the asphalt modifi ed with branched SBS has better performance but worse stability, for it is easier to segregate. 展开更多
关键词 SBS modifi ed asphalt microstructure quantitative index distribution characteristic
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The monitoring of burden distribution uniformity and even sintering technology
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作者 MA Luowen 《Baosteel Technical Research》 CAS 2009年第2期27-30,共4页
After expanding the capacity by widening the trolley of the No. 3 sintering machine, severe uneven sintering occurred in the trolley' s lateral distribution, which affected the output and quality of sinter. In this s... After expanding the capacity by widening the trolley of the No. 3 sintering machine, severe uneven sintering occurred in the trolley' s lateral distribution, which affected the output and quality of sinter. In this study, the quantitative evaluation indices of the burden uniform distribution in the width direction of the sintering machine is introduced for the first time. By measuring the temperature of discharged gas, a plane temperature field is constructed. Through analyzing the temperature field and the burden layer' s differential thermal equilibrium, a mathematical model for evaluating the indices, which is an online reflection of the degree of uniform distribution, is built. Following the improvements in burden distribution equipment ,the optimization of the ignition system and the dynamic adjustment of the process ,the problem of uneven sintering in lateral distribution has been solved, and the quality and the yield of sinter have been improved. 展开更多
关键词 uniform distribution index temperature field mathematical model
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Optimum Simultaneous Allocation of Renewable Energy DG and Capacitor Banks in Radial Distribution Network
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作者 Sivasangari Rajeswaran Kamaraj Nagappan 《Circuits and Systems》 2016年第11期3556-3564,共10页
Nowadays the optimal allocation of distributed generation (DG) in the distribution network becomes the popular research area in restructuring of power system. The capacitor banks introduced in the distribution network... Nowadays the optimal allocation of distributed generation (DG) in the distribution network becomes the popular research area in restructuring of power system. The capacitor banks introduced in the distribution networks for reactive power compensation also have the capacity to minimize the real and reactive power losses occurred in the system. Hence, this research integrates the allocation of renewable energy DG and capacitor banks in the radial distribution network to minimize the real power loss occurred in the system. A two-stage methodology is used for simultaneous allocation of renewable DG and capacitor banks. The optimum location of renewable energy DG and capacitor banks is determined using the distributed generation sitting index (DGSI) ranking method and the optimum sizing of DG and capacitor banks is found out for simultaneous placement using weight improved particle swarm optimization algorithm (WIPSO) and self adaptive differential evolution algorithm (SADE). This two-stage methodology reduces the burden of SADE and WIPSO algorithm, by using the DGSI index in determining the optimal location. Hence the computational time gets reduced which makes them suitable for online applications. By using the above methodology, a comprehensive performance analysis is done on IEEE 33 bus and 69 bus RDNs and the results are discussed in detail. 展开更多
关键词 distributed Generation Capacitor Banks Real Power Loss Radial Distribution Network distributed Generation Sitting index WIPSO SADE
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Image Processing of Corona Virus Using Interferometry
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作者 Abdallah Mohamed Hamed 《Optics and Photonics Journal》 2016年第5期75-86,共12页
A new method of image processing of corona virus based on two and multiple beam interference is suggested. The method is based on measuring the fringe shift with respect to the background interference pattern. The int... A new method of image processing of corona virus based on two and multiple beam interference is suggested. The method is based on measuring the fringe shift with respect to the background interference pattern. The interested application of the corona virus image in confocal microscopy is getting depth information since it has the property of optical sectioning. An accurate measurement of the fringe shift is obtained using multiple beam interference since contrast is higher than that for two beam interference. The refractive index of the corona virus image is deduced from the fringe shift. A MATLAB code is used for the processing of all images. 展开更多
关键词 INTERFERENCE Image Processing Refractive index Distribution of Corona Virus
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Wideband reverberation suppression in beams domain based on angular distribution index
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作者 LI Xuan MA Xiaochuan +1 位作者 HAO Chengpeng YAN Shefeng 《Chinese Journal of Acoustics》 CSCD 2016年第4期384-393,共10页
Based on the properties of wideband source’s spatial spread,an algorithm for reverberation suppression in beams domain is proposed.In an effective observation range,a compact bank of receiving spatial beams is operat... Based on the properties of wideband source’s spatial spread,an algorithm for reverberation suppression in beams domain is proposed.In an effective observation range,a compact bank of receiving spatial beams is operated to transform the data from element domain to beam domain.Angular Distribution Index(ADI) is obtained by comparing to a reference value which is computed by Monte Carlo Integration.ADI decreases with a stronger target echo.Hence,choosing an appropriate threshold of ADI,the target echo can be separated from reverberation by cutting off the high AD components.The filter is compatible with the procedures of beamforming and detection for the current sonar.The computation complexity of the filter is low.The relationships between ADI and frequency,bandwidth,signal-reverberation ratio,are illustrated by a simulation example.The processing results based on the lake-trial and sea-trial data show that reverberation can be significantly suppressed,and threshold choosing for wideband ADI filter is fault tolerant. 展开更多
关键词 ADI Wideband reverberation suppression in beams domain based on angular distribution index LFM
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Potential of exclosure on aboveground biomass carbon stock and ecological fitness of woody species in Jabi Tehnane district, northwestern Ethiopia 被引量:1
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作者 Melkamu Terefe Asmare Abdella Gure 《Ecosystem Health and Sustainability》 SCIE 2019年第1期79-85,I0017,共8页
Assessment of ecological fitness of woody species across land use is critical issues in degraded land restoration.However,little is known about AGBC stored capacity,important value and distribution index of woody spec... Assessment of ecological fitness of woody species across land use is critical issues in degraded land restoration.However,little is known about AGBC stored capacity,important value and distribution index of woody species grows in exclosure and adjacent open lands.Therefore,this research is aimed to(i)analyse impact of exclosure on AGBC(ii)ecological fit species.A random sampling method was employed.Forty sample plots(50m*50m)were used.AGBC stocks(mean±SE)of woody species in adjacent open grazing and exclosure land use of GW site was 0.11±0.07 and 1.24±0.27Mg ha^(-1) respectively.While in adjacent open grazing and exclosure land use of WG site,the value was 0.27±0.03 and 2.79±0.27Mgha^(-1) respectively.In both site exclosure land uses,the proportion of rare,occasional and common woody species were better than their adjacent open grazing land.Cupressus lustanica from open grazing and Vernonia auriculifera from exclosure land use of WG as well as Croton macrostachyus from open grazing and Leucaena leucocephala fromexclosure land use of GWsite were recorded as top ecologically fit species.It is recommended to protect degraded lands via integrating ecologically adapted native species and fully used their diversity to achieve the potential benefits of land restoration. 展开更多
关键词 Aboveground biomass carbon distribution index EXCLOSURE important value index
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