Journal of Intelligent & Fuzzy Systems - Volume 31, issue 2

Authors: Wang, Nini | Xia, Jun | Yin, Jianchuan | Liu, Xiaodong

Article Type: Research Article

Abstract: Detecting temporal and spatial trends of annual and seasonal land surface temperature (LST) can contribute to study the effect of climate change and climate variability on temperature behaviors both in time and space. The temporal and spatial gridded dataset of monthly mean LST series produced by Berkeley Earth were chosen for the analysis of LST trends. The dynamic programming (DP) based segmentation algorithm is a fast and efficient time series segmentation algorithm which can identify multiple change points in a given time series. Multiple change points of annual and seasonal LST average anomaly time series during the period 1880–2013 (reference …to the 20th century average) were identified by the DP based time series segmentation algorithm. Schwarz’s Bayesian information criterion (BIC) was applied to automatically determine the optimal segmentation order. BIC selected one change point for annual and seasonal average LST except for the autumn season’s. Regardless of the number of change points, at the first segment, trends are always increasing and at the last, they are sharply increasing except for the winter season. Moreover, all the change points locate around El Nin ˜ o years, La Nin ˜ a years, and phase transition years of the Pacific decadal oscillation (PDO). Based on optimal time series segmentation results selected by BIC, the spatial distributions of linear trends (slope estimates) of annual and seasonal LST anomalies corresponding to different homogeneous periods are showed. Comparing to adjacent segment, the recent warming trends not only appear in Greenland and the surrounding area, but also dominate most parts of land surface, and significant warming trends appear in high latitude regions of the Northern Hemisphere. Show more

Keywords: Time series segmentation, temporal-spatial variability, trend analysis, climate change

DOI: 10.3233/JIFS-169041

Citation: Journal of Intelligent & Fuzzy Systems, vol. 31, no. 2, pp. 1121-1131, 2016

Authors: Yu, Jianhang | Zhang, Xiaoyan | Zhao, Zhenhua | Xu, Weihua

Article Type: Research Article

Abstract: The graded rough set and multi-granulation rough set are two significant generalized rough set models which be constructed on the indiscernibility relation. They solve the issues that the degree of overlap between the equivalence class and basic set in different view points of quantitative information. The purpose of this study is that research the good points of graded rough set in the multi-granulation environment which in different granules have different grades based on dominance relation. Three new types of multi-granulation with different grades rough set models are proposed, which include the optimistic, pessimistic and mean multi-granulation with different grades rough …set. Then, their principal structure, basic properties and serval kinds of uncertainty measure methods are investigated as well. Furthermore, an experimental evaluation about urban investment is utilized to verify the proposed properties, which is valuable for applying these theories to deal with practical issues. Show more

Keywords: Different grades, dominance relation, graded rough set, multi-granulation rough set, uncertainty measures

DOI: 10.3233/JIFS-169042

Citation: Journal of Intelligent & Fuzzy Systems, vol. 31, no. 2, pp. 1133-1144, 2016

Authors: Li, Chao | Chu, Xiaogeng | Chen, Yingwu | Xing, Lining

Article Type: Research Article

Abstract: Genetic Algorithms are efficient for the travelling salesman problem, but they have a premature convergence problem resulting in suboptimal solutions. As the initialization step has a profound impact on the algorithm’s performance, this study proposes a knowledge-based initialization technique to learn the patterns of evolved populations, and integrates four heuristic strategies to generate the initial population. Advanced initial solutions and high quality gene blocks can be quickly created with this method. Instances in the TSPLIB library are used to set the parameters and test different initialization methods. The results show that this proposed technique can improve the initial population and …optimization performance of genetic algorithms. Show more

Keywords: Genetic algorithm, travelling salesman problem, initial population, heuristic technique

DOI: 10.3233/JIFS-169043

Citation: Journal of Intelligent & Fuzzy Systems, vol. 31, no. 2, pp. 1145-1152, 2016

Article Type: Research Article

DOI: 10.3233/JIFS-169044

Citation: Journal of Intelligent & Fuzzy Systems, vol. 31, no. 2, pp. 1153-1153, 2016