• 제목/요약/키워드: Cluster expansion

Search Result 115, Processing Time 0.024 seconds

Selecting Optimal Locations for Bicycle Lanes to Prevent Accidents in Seoul (서울특별시 자전거 안전사고 예방을 위한 자전거 도로 최적 입지 선정: 자전거 전용도로 및 전용차로를 중심으로)

  • Ji-eun Kim;Sumin Nam;ZoonKy Lee
    • The Journal of Bigdata
    • /
    • v.8 no.2
    • /
    • pp.45-54
    • /
    • 2023
  • Seoul's public bicycle system, 'Ttareungyi,' introduced in 2015, has achieved an annual ridership of 40 million in 2022. Similarly, electric scooters, a type of personal mobility device, surpassed one million riders in 2020 due to various sharing platforms. However, the major roadways for these new transportation, bicycle lanes, are notably insufficient compared to other forms of transport. Hence, this study proposes an optimal location selection method for bicycle lanes in Seoul to prevent accidents and enhance bicycle ride safety. The location selection process prioritizes road safety concerning bicycle accident risk. Using regression models, high-risk areas for bicycle accidents are identified. Cluster analysis categorizes these areas into six clusters, each suggesting suitable types of bicycle lanes based on cluster-specific characteristics. We hope that this study will contribute to the improvement of Seoul's transportation environment, including the expansion of dedicated bicycle lanes and lanes for personal mobility devices.

A Study on the Global Diffusion through a Case for the Expansion of the T-DMB into Vietnam (지상파 DMB 베트남 진출 사례를 통한 T-DMB 글로벌 확산 연구)

  • Eun, Jong-Won;Park, Sung-Yul;Yoon, Dong-Sung
    • Journal of the Korean Academic Society of Industrial Cluster
    • /
    • v.4 no.1
    • /
    • pp.1-13
    • /
    • 2010
  • The T-DMB which was developed by the convergence of digital broadcasting technology and communication technology provides us with very good quality of music like CD, and provides TV services in a super express train like the KTX whose velocity is over 300 Km per hour. The T-DMB is diffusing toward the world as a technology which is be able to provide the various convergent services of broadcasting and communication through mobile phone, PDA, dedicated terminal, and so on. A business model needed for the diffusion of the T-DMB toward the world was established and utilized to expand the T-DMB into Vietnam in the paper. In addition, this paper describes a case for the establishment of the T-DMB system in order to provide the paid services in Vietnam. It is expected that the expansion of the T-DMB into Vietnam will make a great contribution to the diffusion of the T-DMB toward the world.

  • PDF

Alveolar restoration following rapid maxillary expansion with and without corticotomy: A microcomputed tomography study in sheep

  • Le, My Huy Thuc;Hayaty, Abu Kasim Noor;Zaini, Zuraiza Mohamad;Dom, Sulaiman Md;Ibrahim, Norliza;Radzi, Zamri Bin
    • The korean journal of orthodontics
    • /
    • v.49 no.4
    • /
    • pp.235-245
    • /
    • 2019
  • Objective: This study examined bone microstructure restoration after rapid maxillary expansion (RME) with and without corticotomy over multiple retention periods. Methods: Eighteen male Dorper sheep were randomly distributed into three groups (n = 6 each group): group 1, RME with corticotomy on the buccal and palatal sides; group 2, conventional RME treatment; and group 3, no treatment. Post-RME, trabecular bone microstructure and new bone formation were evaluated by using microcomputed tomography (microCT) and histomorphometry after a 4- or 12-week retention period. Intergroup differences in bone quality and bone remodeling were analyzed by using two-way analysis of variance with Bonferroni post-hoc test. Results: The bone volume fraction (bone volume [BV]/total volume [TV]) values relative to the control in groups 1 and 2 were 54.40% to 69.88% after the 4-week retention period and returned to approximately 80% after the 12-week retention period. The pooled BV/TV values of the banded teeth in groups 1 and 2 were significantly lower than those of the control after the 4-week retention period (p < 0.05). However, after the 12-week retention period, the pooled BV/TV values in group 2 were significantly lower than those in groups 1 and 3 (p < 0.05). Histomorphological analysis showed that the new bone formation area in group 1 was approximately two to three times of those in group 2 and control. Conclusions: Corticotomy significantly enhanced the restoration of bone quality after the retention periods for banded teeth. This benefit might result from the increased new bone formation after corticotomy.

Quality Changes of Fresh-Cut Tumeric by Packaging Methods during Storage (포장방법에 따른 세절 생울금의 저장 중 품질 변화)

  • Kim, Dong-Hoo;Han, Jin-Soo;Woo, In-Bong;Jung, Jun-Jae;Park, Si-Woo;Heo, Kyung-Chel;Ha, Ju-hyeung;Yoon, Chan-Suk
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.23 no.3
    • /
    • pp.151-162
    • /
    • 2017
  • The purpose of this study was to investigate the quality change of fresh-cut tumeric (Curcuma Longa Linne) according to packaging method during storage time. The fresh-cut tumeric were packaged in three different methods : degassing valve packaging (DVP), $CO_2$ gas absorber packaging (CAP) and micro-perforated packaging (MPP). After the samples were packaged, they were stored for 15 days at 4 and $23^{\circ}C$ respectively. The following parameters were observed to indicate the quality changes of the samples: weight loss, CIE $L^*a^*b^*$ colour difference, variation of gas composition inside the package, curcumin contents and changes in hardness of fresh-cut tumeric. DVP did not effectively release $CO_2$ gas to the outside. MPP was suitable to release $CO_2$ gas. However, MPP showed very fast browning and erosion, because a large amount of oxygen was introduced through the perforated hole on the film. CAP was most effective packaging method to inhibit browning, to prevent expansion of the packaging by $CO_2$ gas and to minimize weight loss of fresh-cut tumeric.

A study on the Wonju Medical Equipment Industry Cluster (원주의료기기산업 클러스터의 형성과정에 관한 연구)

  • Lee, Woo-Chun;Yoon, Hyung-Ro
    • Journal of the Korean Academic Society of Industrial Cluster
    • /
    • v.1 no.1
    • /
    • pp.67-86
    • /
    • 2007
  • Wonju Medical Equipment Industry, despite of its short history, poor sales and weak manpower and so on, have shown remarkable outcomes in a relatively short period. At the end of 2007, totally 79 enterprises (only 4.6% of whole enterprises in Korea) made 10% of the nationwide production and 15% of the nationwide exports with an annual average growth rate of 66.7%, contributing domestic medical equipment industry tremendously. In addition, many leading medical equipment enterprises in various fields already moved or plan to move to Wonju, accelerating Wonju Medical Equipment Cluster. Wonju Medical Equipment Industry Cluster now enters into the growth stage, getting out of the initial business setup stage. Especially, the nomination of Wonju cluster project from the government accelerates networking (e.g. the development of the universal parts, the establishment of the mutual collaboration model among enterprises, and the mutual marketing), making a rapid growth in Wonju Medical Equipment Industry. Wonju Medical Equipment Industry Cluster revealed positive outcomes despite of the weakness in investment size and infra-structure comparing with the other medical industry cluster in the advanced country, while many domestic enterprises pursued their own growth models and thus failed to promote the international competitive power. Wonju Medical Equipment Industry has been developed rapidly. However, there are many challenging problems to support enterprises: small R&D investment and thus weak technology power, difficulties in recruiting R&D engineers, and poor marketing capabilities, financial infrastructure & policies, and network architecture. In order to develop a world-competitive medical equipment industry cluster at Wonju, the complement of infrastructures, the technology innovation, the mutual marketing, and the network expansion to support enterprises are further required. Wonju' s experiences in developing medical equipment industry so far suggest that our own flexible cluster model considering the industry structure and maturity for different regions should be developed, and specific action plans from the local and central governments based on their systematic strategies for industry development should be implemented in order to build world-competitive industry clusters in Korea.

  • PDF

Investment Priority and ImProvements in the Northeast Asia Logostics Hub Road Map (한국의 동북아 물류중심로드맵 투자우선순위와 개선방안)

  • Choe, Seok-Beom
    • Journal of Korea Port Economic Association
    • /
    • v.20 no.2
    • /
    • pp.187-216
    • /
    • 2004
  • Northeast Asia logistics hub strategy was undertaken by Korean Government to gain a national competitive advantage in Northeast Asia. Current Government has Northeast Asian Economic Hub Strategy including construction of SOC in Northeast Asia for promoting peace, promotion of formation of Northeast Asia Community, logistics hub, Financial hub and national innovation for R&D Cluster. To realize Northeast Asian logistics hub, the Northeast Asia logistics hub road map has undertaken as follows: expansion of logistics infra in Incheon Airport, Busan Port and Gwangyang Port, systematic improvements such as adjustment of investment distribution, special logistics companies, transparent customs in logistics transactions, logistics manpower, improvement of system supporting global logistics and attraction of international logistics companies to the logistics center, construction of seamless and paperless logistics information network, Northeast Asia railway infra. The purpose of this paper is to study investment priority and improvements in the Northeast Asia Logistics Hub Road Map and to contribute to gain the national competitive advantage as logistics hub in Northeast Asia

  • PDF

User Query Expansion Through Keyword Similarity Ranking Algorithm Us ins Cluster ing Methods (클러스터링 기법을 이용한 키워드 유사도 순위화 알고리즘에 따른 사용자 질의 확장)

  • 이상훈;김기태
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2003.04c
    • /
    • pp.479-481
    • /
    • 2003
  • 본 논문에서는 여러 가지 클러스터링 기법들을 사용하여 키워드 유사도롤 순위화하여 사용자의 질의를 확장하는 기법을 제안한다. 클러스터링 기법에는 연관(Association) 클러스터링, 메트릭(Metric) 클러스터링, 스칼라(Scalar) 클러스터링 기법을 사용하고, 이들간의 가중치를 적절히 조절하여 검색 시스템을 만든다. 사용자의 질의가 주어졌을 때, 질의 키워드와 연관된 키워드들을 순위화 하여 사용자에게 보여주고, 사용자의 추가입력을 받아서 질의를 확장한다. 사용자가 적당한 질의어로 판단하여 확장된 질의로 검색을 수행할 때까지 이 과정을 반복한다. 실험에서 사용한 문헌집합은 Korea Herald의 2003년 1월과 2월의 경제 관련 기사들을 수집하여 사용하였고, 실험을 거쳐서 질의를 확장한 결과 만족할 만한 결과가 도출되었다.

  • PDF

THE DYNAMICAL EVOLUTION OF GLOBULAR CLUSTERS WITH STELLAR MASS LOSS

  • Kim, Chang-Hwan;Chun, Mun-Suk;Min, Kyung-W.
    • Journal of Astronomy and Space Sciences
    • /
    • v.8 no.1
    • /
    • pp.11-23
    • /
    • 1991
  • The dynamical evolution of globular clusters is studied using the orbit-averaged multicomponent Fokker-Planck equation. The original code developed by Cohn(1980) is modi-fied to include the effect of stellar evolutions. Plommer's model is chosen as the initial density distribution with the initial mass function index $\alpha$=0.25, 0.65, 1.35, 2.35, and 3.35. The mass loss rate adopted in this work follows that of Fusi-Pecci and Renzini(1976). The stellar mass loss acts as the energy source, and thus affects the dynamical evolution of globular clusters by slowing down the evolution rate and extending the core collapse time Tcc. And the dynamical length scale $$R_c, $$R_h is also extended. This represents the expansion of cluster due to the stellar mass loss.

  • PDF

A STUDY ON THE NURBS GRID GENERATION AND GRID CONTROL (NURBS를 이용한 격자생성 및 제어기법)

  • Yoon, Yong-Hyun
    • Journal of computational fluids engineering
    • /
    • v.12 no.3
    • /
    • pp.20-28
    • /
    • 2007
  • A fast and robust method of grid generation to multiple functions has been developed for flow analysis in three dimensional space. It is based on the Non-Uniform Rational B-Spline(NURBS) of an approximation method. Many of NURBS intrinsic properties are introduced and much more easily understood. The grid generation method, details of numerical implementation. examples of application, and potential extensions of the current method are illustrated in this paper. The object of this study is to develop the surface grid generation and the grid cluster techniques capable of resolving complex flows with shock waves, expansion waves, shear layers. The knot insert method of Non-Uniform Rational B-Spline seems well worked. In addition, NURBS has been widely utilized to generate grids in the computational fluid dynamics community. Computational examples associated with practical configurations have shown the utilization of the algorithm.

A Study on the Developing Strategies of Knowledge based Industry in ChunChon Area for the Digital Age. (디지털시대 춘천지역 지식기반산업의 발전방안에 관한 연구)

  • Kim, Chi-Ho;La, Kong-Woo;Min, Tae-Hong
    • International Commerce and Information Review
    • /
    • v.8 no.3
    • /
    • pp.3-21
    • /
    • 2006
  • This study aims to explore the developing strategies of knowledge based industry in ChunChon Area. This study suggests several strategies for promoting local development in Chunchon Area as follows ; first, building of local innovation system in chunchon area and convergence and diffusion of knowledge based industries. second, making of industrial environment suitable to developing knowledge based industries. third, the establishment of overall industrial supporting systems. fourth, expansion of industrial infra and prevention of the brain drain. fifth, transformation of industrial complex into innovation clusters. The result of this study will be useful for the chief executives officers to make more rational decision making for industrial developing strategies is related to the Knowledge based Industries. The paper also strives to provoke debate in this area with to encouraging further research on the topic.

  • PDF