• Title/Summary/Keyword: Neighborhood-Based

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A Stigmergy-and-Neighborhood Based Ant Algorithm for Clustering Data

  • Lee, Hee-Sang;Shim, Gyu-Seok
    • Management Science and Financial Engineering
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    • v.15 no.1
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    • pp.81-96
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    • 2009
  • Data mining, specially clustering is one of exciting research areas for ant based algorithms. Ant clustering algorithm, however, has many difficulties for resolving practical situations in clustering. We propose a new grid-based ant colony algorithm for clustering of data. The previous ant based clustering algorithms usually tried to find the clusters during picking up or dropping down process of the items of ants using some stigmergy information. In our ant clustering algorithm we try to make the ants reflect neighborhood information within the storage nests. We use two ant classes, search ants and labor ants. In the initial step of the proposed algorithm, the search ants try to guide the characteristics of the storage nests. Then the labor ants try to classify the items using the guide in-formation that has set by the search ants and the stigmergy information that has set by other labor ants. In this procedure the clustering decision of ants is quickly guided and keeping out of from the stagnated process. We experimented and compared our algorithm with other known algorithms for the known and statistically-made data. From these experiments we prove that the suggested ant mining algorithm found the clusters quickly and effectively comparing with a known ant clustering algorithm.

A Study on Characteristics of cul de sac Road in Old Settlements of Downtown Jeju - Focus on a Collaborative Development based on a neighborhood plan - (제주시 원도심 골목공간의 특성에 관한 연구 - 시가지 재정비 제도를 중심으로 -)

  • Yang, Gon;Yi, Sang-Ho;Yi, Yong Kyu
    • Journal of the Korean Institute of Rural Architecture
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    • v.17 no.2
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    • pp.1-8
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    • 2015
  • The study is to find regional characteristics of the old town of Jeju city, "Mu-gun-sung," through researches of the status of the spatial structure in the cul de sac roads of the area. In particular, the status and characteristics of the area are clearly defined with the typology of the cul de sac roads based on the urban renewal regulations. The results are listed as follows: First, there are buildings from various periods in the area. Second, it is comparatively analyzed that there are the similarities and differences in Collaborative Development based on a neighborhood plan in Japan and Korea which pursue conservative renewals of the cule de sac roads. Third, the status and characteristics of the area are clarified through the analysis of the types of the cul de sac roads.

GIS-oriented Measurement Indicces of Accessibility of the Neighborhood Park in Seoul (GIS를 활용한 서울시 도시근교공원의 접근성 지표에 관한 연구)

  • 허미선;진양조
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.3
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    • pp.42-56
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    • 1996
  • The citizens seek to maximize convenience, pleasantness and safety when they use urban facilities. However, existing practices of urban neighborhood parks have applied not qualitative standards such as adequacy, efficiency, accessibility, equity, or socioeconomic issues but very limited quantitative standards such as area per person. Therefore it is not rare that citizens have lost their accessibility to near-by neighborhood parks. And park regulations based on the distance of lien are supposed to be uniformally accomplished regardless of the consideration about users or geographical special situations. Futhermore, it has been found that some urban neighborhood parks don't reach to the standards given by the regulations. This study tries to accomplished several purposes. The first purpose is to extract the boundary of real user-accessible zones derived from the city survey. Comparing with boundary of real user-accessible zones, the second one is to propose the most efficient measurement indices among many accessibility measurement index. Based upon the above arguments, the last one is to review the propriety of the access distances(e.g., semidiameter) of an urban neighborhood park in a law. The measurement indices of accessibility examined in this study are walking distance, walking time and walking difficulty. The comparison of visual discrimination, the comparison of area and the comparison of differences of maximum distance showed similar results. Each index can also be compared in the size of area and differences of maximum distance. Walking difficulty with the turning showed the best measurement values among the measurement indices. This indicates that walking difficulty with crossing and/or turning may be another important indices in measuring accessibility, while other existing studues have mainly dealt with walking time and distance as accessibility indices. The results of this study also supported that the existing regulations related to park allocation(e.g., access diameter) are close to the findings of this study.

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A Dual-Structured Self-Attention for improving the Performance of Vision Transformers (비전 트랜스포머 성능향상을 위한 이중 구조 셀프 어텐션)

  • Kwang-Yeob Lee;Hwang-Hee Moon;Tae-Ryong Park
    • Journal of IKEEE
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    • v.27 no.3
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    • pp.251-257
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    • 2023
  • In this paper, we propose a dual-structured self-attention method that improves the lack of regional features of the vision transformer's self-attention. Vision Transformers, which are more computationally efficient than convolutional neural networks in object classification, object segmentation, and video image recognition, lack the ability to extract regional features relatively. To solve this problem, many studies are conducted based on Windows or Shift Windows, but these methods weaken the advantages of self-attention-based transformers by increasing computational complexity using multiple levels of encoders. This paper proposes a dual-structure self-attention using self-attention and neighborhood network to improve locality inductive bias compared to the existing method. The neighborhood network for extracting local context information provides a much simpler computational complexity than the window structure. CIFAR-10 and CIFAR-100 were used to compare the performance of the proposed dual-structure self-attention transformer and the existing transformer, and the experiment showed improvements of 0.63% and 1.57% in Top-1 accuracy, respectively.

A study on the Urban Growth Model of Gimhae City Using Cellular Automata (셀룰라 오토마타를 이용한 김해시의 도시성장모형에 관한 연구 - 1987~2001년을 중심으로 -)

  • Lee, Sung Ho;Yun, Jeong Mi;Seo, Kyung Chon;Nam, Kwang Woo;Park, Sang Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.7 no.3
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    • pp.118-125
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    • 2004
  • The purpose of this study is to decide an appropriate neighborhood and a transition rule of cellular automata by analyzing the past growth process of urban areas in Gimhae. With cellular automata which can manage the change based on the dynamic model and time, this study analyzes the urban growth of Gimhae from 1987 to 2001. Also, through the simulation of different types for neighborhood and transition rules, we can find the appropriate neighborhood and the transition rule for Gimhae. In conclusion, the forecast of physical urban growth pattern is more accurate under conditions when the number of matrixes for the neighborhood is small, the shape of the neighborhood is rectangular, "${\alpha}$" value, which control the pace of urban growth, is low and the transition possibility ($P_{ij}$) is high.

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An Analysis of Keywords Related to Neighborhood Healing Gardens Using Big Data (빅데이터를 활용한 생활밀착형 치유정원 연관키워드 분석)

  • Huang, Zhirui;Lee, Ai-Ran
    • Land and Housing Review
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    • v.13 no.2
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    • pp.81-90
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    • 2022
  • This study is based on social needs for green healing spaces assumed to enhance mental health in a city. This study proposes development directions through the analysis of modern social recognition factors for neighborhood gardens. As a research method, web information data was collected using Textom among big data tools. Text Mining was conducted to extract elements and analyze their relationship through keyword analysis, network analysis, and cluster analysis. As a result, first, the healing space and the healing environment were creating an eco-friendly healthy environment in a space close to the neighborhood within the city. Second, neighborhood gardens included projects and activities that involved government, local administration, and citizens by linking facilities as well as living culture and urban environments. These gardens have been reinforced through green welfare and service programs. In conclusion, friendly gardens in the neighborhood for the purpose of public interest, which are beneficial to mental health, are green infrastructures as a healing environment that can produce positive effects.

An Experimental Study of Image Thresholding Based on Refined Histogram using Distinction Neighborhood Metrics

  • Sengee, Nyamlkhagva;Purevsuren, Dalaijargal;tumurbaatar, Tserennadmid
    • Journal of Multimedia Information System
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    • v.9 no.2
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    • pp.87-92
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    • 2022
  • In this study, we aimed to illustrate that the thresholding method gives different results when tested on the original and the refined histograms. We use the global thresholding method, the well-known image segmentation method for separating objects and background from the image, and the refined histogram is created by the neighborhood distinction metric. If the original histogram of an image has some large bins which occupy the most density of whole intensity distribution, it is a problem for global methods such as segmentation and contrast enhancement. We refined the histogram to overcome the big bin problem in which sub-bins are created from big bins based on distinction metric. We suggest the refined histogram for preprocessing of thresholding in order to reduce the big bin problem. In the test, we use Otsu and median-based thresholding techniques and experimental results prove that their results on the refined histograms are more effective compared with the original ones.

a improved neighborhood selection of simulated annealing technique for test data generation (테스트 데이터 생성을 위한 개선된 이웃 선택 방법을 이용한 담금질 기법 기술)

  • Choi, Hyun Jae;Lee, Seon Yeol;Chae, Heung Seok
    • Journal of Software Engineering Society
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    • v.24 no.2
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    • pp.35-45
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    • 2011
  • Simulated annealing has been studied a long times. And it is one of the effective techniques for test data generation. But basic SA methods showed bad performance because of neighborhood selection strategies in the case of large input domain. To overcome this limitation, we propose new neighborhood selection approach, Branch Distance. We performs case studies based on the proposed approach to evaluate it's performance and to compare it whit basic SA and Random test generation. The results of the case studies appear that proposed approach show better performance than the other approach.

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Neighborhood Reduction in Local Search based on Geospatial Relation for Multi Depot Vehicle Routing Problems

  • Tamashiro, Hiroshi;Nakamura, Morikazu;Tamaki, Shiro;Onaga, Kenji
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.595-598
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    • 2002
  • This paper proposes neighborhood reduction techniques in local search of the customer decomposition subproblem in the Multi Depots Vehicle Routing Problem with Time Windows (MDVRPTW) by using geospatial relation among depots and customers. The neighborhood of the customer decomposition subproblem can be simply and well defined but it should include excessively bad solution candidates. Our techniques find such candidates by using information of the problem domain, geographical relation. We use our techniques in Tabu Search and evaluate the effectiveness in computer experiment.

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A Study on the Fatigue Crack Growth Characteristics for the Weldment of Carbon steel-Stainless steel (탄소강-스테인리스강 용접부의 피로균열진전 특성에 관한 연구)

  • 권재도;김우현;김길수;박중철;배용탁;김중형
    • Journal of Welding and Joining
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    • v.16 no.4
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    • pp.47-54
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    • 1998
  • Various equipments in plants are welded with two different materials and it is required to investigate the effects of fatigue crack propagation on the neighborhood of a welded portion. The characteristics of fatigue crack growth in the base metal of carbon and stainless steel, in the carbon and stainless steel sides located in the neighborhood of welded portion (carbon/stainless steel), respectively and welded portion, are investigated. The results show that the crack growth in the welded portion (carbon/stainless steel) is an average value of the crack growths in the carbon and stainless steel respectively located in the neighborhood of the welded portion. It is found that the crack growth in the welded portion is not significantly different from those in the carbon and stainless steel sides. Hence it can be concluded that the structure welded with two different materials wold not impede the integrity based on the fatigue crack growth.

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