The efficiency of sample-based indices proposed to quantify the spatial distribution of trees is influenced by the structure of tree stands, environmental heterogeneity and degree of aggregation. We evaluated 10 commo...The efficiency of sample-based indices proposed to quantify the spatial distribution of trees is influenced by the structure of tree stands, environmental heterogeneity and degree of aggregation. We evaluated 10 commonly used distance-based and 10 density-based indices using two structurally different stands of wild pistachio trees in the Zagros woodlands, Iran, to assess the reliability of each in revealing stand structure in woodlands. All trees were completely stem-mapped in a nearly pure（40 ha） and a mixed（45 ha） stand. First, the inhomogeneous pair correlation function [g（r）] and the Clark-Evans index（CEI） were used as references to reveal the true spatial arrangement of all trees in these stands. The sampled data were then evaluated using the 20 indices.Sampling was undertaken in a grid based on a square lattice using square plots（30 m 9 30 m） and nearest neighbor distances at the sample points. The g（r） and CEI statistics showed that the wild pistachio trees were aggregated in both stands, although the degree of aggregation was markedly higher in the pure stand. Three distance- and six density-based indices statistically verified that the wild pistachio trees were aggregated in both stands. The distance-based Hines and Hines statistic（ht） and the densitybased standardised Morisita（Ip）, patchiness（IP） and Cassie（CA） indices revealed aggregation of the trees in the two structurally different stands in the Zagros woodlands and the higher clumping in the pure stand, whereas the other indices were not sensitive enough.展开更多
We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provi...We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provide a new criterion of iterate acceptance. The convergence can be ensured under some conditions. The numerical result shows that this method is practical and efficient.展开更多
Performance-based seismic design(PBSD) aims to assess structures at different damage states. Since damage can be directly associated to displacements, seismic design with consideration of displacement seems to be logi...Performance-based seismic design(PBSD) aims to assess structures at different damage states. Since damage can be directly associated to displacements, seismic design with consideration of displacement seems to be logical. In this study, simple formulae to estimate the peak floor displacement patterns of eccentrically braced frames(EBFs) at different performance levels subjected to earthquake ground motions are proposed. These formulae are applicable in a PBSD and especially in direct displacement-based design(DDBD). Parametric study is conducted on a group of 30 EBFs under a set of 15 far field and near field accelerograms which they scaled to different amplitudes to adapt various performance levels. The results of thousands of nonlinear dynamic analyses of EBFs have been post-processed by nonlinear regression analysis in order to recognize the major parameters that influence the peak displacement pattern of these frames. Results show that suggested displacement patterns have relatively good agreement with those acquired by an exact nonlinear dynamic analysis.展开更多
Foeused on the lack of proper organization for patterns in the development of pattern based software, a POMSDP model with layered tree structure for organizing patterns during the process of development was put torwar...Foeused on the lack of proper organization for patterns in the development of pattern based software, a POMSDP model with layered tree structure for organizing patterns during the process of development was put torward. The model and its interrelated eoneepts were strictly defined and introduced by applying the theory of set, symbolie logic and pattern, which ensures the correctness, maturity and expansibility of the model. The expansibility of the model was discussed mainly. The basic realization and the application in the automatic query system were presented. Based on the existing software development methods, the POMSDP model resolves the problem of chaos in the application of patterns, strengthens the controllability of the system, and facilitates the improvement, maintenance, expansion, and especially the reengineering of the software system.展开更多
Recently, the National Typhoon Center （NTC） at the Korea Meteorological Administration launched a track-pattern-based model that predicts the horizontal distribution of tropical cyclone （TC） track density from Jun...Recently, the National Typhoon Center （NTC） at the Korea Meteorological Administration launched a track-pattern-based model that predicts the horizontal distribution of tropical cyclone （TC） track density from June to October. This model is the first approach to target seasonal TC track clusters covering the entire western North Pacific （WNP） basin, and may represent a milestone for seasonal TC forecasting, using a simple statistical method that can be applied at weather operation centers. In this note, we describe the procedure of the track-pattern-based model with brief technical background to provide practical information on the use and operation of the model. The model comprises three major steps. First, long-term data of WNP TC tracks reveal seven climatological track clusters. Second, the TC counts for each cluster are predicted using a hybrid statistical-dynamical method, using the seasonal prediction of large-scale environments. Third, the final forecast map of track density is constructed by merging the spatial probabilities of the seven clusters and applying necessary bias corrections. Although the model is developed to issue the seasonal forecast in mid-May, it can be applied to alternative dates and target seasons following the procedure described in this note. Work continues on establishing an automatic system for this model at the NTC.展开更多
Shuyang,an industrial base of wrapped yarn,enjoys the largest number of equipment and largest production in China or even in the world.Shuyang intelligent knitting industrial park was laid a foundation on March 10,and...Shuyang,an industrial base of wrapped yarn,enjoys the largest number of equipment and largest production in China or even in the world.Shuyang intelligent knitting industrial park was laid a foundation on March 10,and factory workshops in 130,000 square meters are topped off in less than three months in the first construction stage,which is 6 months earlier than planned.What is more unexpected is that they are sold out展开更多
Patterned-based time series segmentation (PTSS) is an important task for many time series data mining applications. In this paper, according to the characteristics of PTSS, a generalized model is proposed for PTSS. Fi...Patterned-based time series segmentation (PTSS) is an important task for many time series data mining applications. In this paper, according to the characteristics of PTSS, a generalized model is proposed for PTSS. First, a new inter-pretation for PTSS is given by comparing this problem with the prototype-based clustering (PC). Then, a novel model, called clustering-inverse model (CI-model), is presented. Finally, two algorithms are presented to implement this model. Our experimental results on artificial and real-world time series demonstrate that the proposed algorithms are quite effective.展开更多
基金supported by Vice Chancellor for Research,Shiraz University,IranErasmus Mundus scholarship for travel to Goettingen,Germany
文摘The efficiency of sample-based indices proposed to quantify the spatial distribution of trees is influenced by the structure of tree stands, environmental heterogeneity and degree of aggregation. We evaluated 10 commonly used distance-based and 10 density-based indices using two structurally different stands of wild pistachio trees in the Zagros woodlands, Iran, to assess the reliability of each in revealing stand structure in woodlands. All trees were completely stem-mapped in a nearly pure（40 ha） and a mixed（45 ha） stand. First, the inhomogeneous pair correlation function [g（r）] and the Clark-Evans index（CEI） were used as references to reveal the true spatial arrangement of all trees in these stands. The sampled data were then evaluated using the 20 indices.Sampling was undertaken in a grid based on a square lattice using square plots（30 m 9 30 m） and nearest neighbor distances at the sample points. The g（r） and CEI statistics showed that the wild pistachio trees were aggregated in both stands, although the degree of aggregation was markedly higher in the pure stand. Three distance- and six density-based indices statistically verified that the wild pistachio trees were aggregated in both stands. The distance-based Hines and Hines statistic（ht） and the densitybased standardised Morisita（Ip）, patchiness（IP） and Cassie（CA） indices revealed aggregation of the trees in the two structurally different stands in the Zagros woodlands and the higher clumping in the pure stand, whereas the other indices were not sensitive enough.
文摘We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provide a new criterion of iterate acceptance. The convergence can be ensured under some conditions. The numerical result shows that this method is practical and efficient.
文摘Performance-based seismic design(PBSD) aims to assess structures at different damage states. Since damage can be directly associated to displacements, seismic design with consideration of displacement seems to be logical. In this study, simple formulae to estimate the peak floor displacement patterns of eccentrically braced frames(EBFs) at different performance levels subjected to earthquake ground motions are proposed. These formulae are applicable in a PBSD and especially in direct displacement-based design(DDBD). Parametric study is conducted on a group of 30 EBFs under a set of 15 far field and near field accelerograms which they scaled to different amplitudes to adapt various performance levels. The results of thousands of nonlinear dynamic analyses of EBFs have been post-processed by nonlinear regression analysis in order to recognize the major parameters that influence the peak displacement pattern of these frames. Results show that suggested displacement patterns have relatively good agreement with those acquired by an exact nonlinear dynamic analysis.
文摘Foeused on the lack of proper organization for patterns in the development of pattern based software, a POMSDP model with layered tree structure for organizing patterns during the process of development was put torward. The model and its interrelated eoneepts were strictly defined and introduced by applying the theory of set, symbolie logic and pattern, which ensures the correctness, maturity and expansibility of the model. The expansibility of the model was discussed mainly. The basic realization and the application in the automatic query system were presented. Based on the existing software development methods, the POMSDP model resolves the problem of chaos in the application of patterns, strengthens the controllability of the system, and facilitates the improvement, maintenance, expansion, and especially the reengineering of the software system.
基金funded by the Korea Meteorological Administration Research and Development Program under Grant CATER 2012-2040supported by the BK21 project of the Korean government
文摘Recently, the National Typhoon Center （NTC） at the Korea Meteorological Administration launched a track-pattern-based model that predicts the horizontal distribution of tropical cyclone （TC） track density from June to October. This model is the first approach to target seasonal TC track clusters covering the entire western North Pacific （WNP） basin, and may represent a milestone for seasonal TC forecasting, using a simple statistical method that can be applied at weather operation centers. In this note, we describe the procedure of the track-pattern-based model with brief technical background to provide practical information on the use and operation of the model. The model comprises three major steps. First, long-term data of WNP TC tracks reveal seven climatological track clusters. Second, the TC counts for each cluster are predicted using a hybrid statistical-dynamical method, using the seasonal prediction of large-scale environments. Third, the final forecast map of track density is constructed by merging the spatial probabilities of the seven clusters and applying necessary bias corrections. Although the model is developed to issue the seasonal forecast in mid-May, it can be applied to alternative dates and target seasons following the procedure described in this note. Work continues on establishing an automatic system for this model at the NTC.
文摘Shuyang,an industrial base of wrapped yarn,enjoys the largest number of equipment and largest production in China or even in the world.Shuyang intelligent knitting industrial park was laid a foundation on March 10,and factory workshops in 130,000 square meters are topped off in less than three months in the first construction stage,which is 6 months earlier than planned.What is more unexpected is that they are sold out
文摘Patterned-based time series segmentation (PTSS) is an important task for many time series data mining applications. In this paper, according to the characteristics of PTSS, a generalized model is proposed for PTSS. First, a new inter-pretation for PTSS is given by comparing this problem with the prototype-based clustering (PC). Then, a novel model, called clustering-inverse model (CI-model), is presented. Finally, two algorithms are presented to implement this model. Our experimental results on artificial and real-world time series demonstrate that the proposed algorithms are quite effective.
