• Title/Summary/Keyword: neighborhood network

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Adaptive Location Management Scheme for PNNI-Based Hierarchical Wireless ATM Networks (PNNI 기반의 계층적 무선 ATM 망에서 적응적 위치 관리 기법)

  • 김도현;조유제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.5A
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    • pp.863-872
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    • 2001
  • 본 논문에서는 PNNI(Private Network to Network Interface) 기반의 무선 ATM 망에서 이웃(neighborhood)과 이동 단말기의 위치 관계를 고려하여 계층화된 위치 등록기에 의한 적응적 위치 관리 기법을 제시한다. 제안된 위치 추적 과정에서는 단말기의 위치 영역을 홈(home) 이웃과 외부(foreign) 이웃으로 구분하고, 홈 이웃에서는 최하위 레벨의 위치 등록기와 홈 위치 등록기에 단말기의 위치를 등록하고 외부 이웃에서는 각 계층의 위치 등록기에 위치를 등록한다. 착신 단말기, 발신 단말기와 착신측 홈 이웃의 위치 관계를 고려하여 최소한의 비용으로 위치 파악 및 호 설정 과정을 수행한다. 그리고, PNNI 기반의 무선 ATM 망에서 제안된 적응적 위치 관리 기법을 기존 LR(Location Registers) 기법과 위치 관리비용 측면에서 성능을 비교하여 우수한 성능을 가지는 것을 알 수 있다.

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A Neural Network Model and Reinforcement Learning for Dynamic Formation Moving and Obstacle Avoidance of Autonomous Mobile Robot (자율이동로봇의 동적 편대 헝성과 장애물 회피를 위한 신경망 구조 및 강화학습)

  • Min, Suk-Ki;Shin, Suk-Young;Kang, Hoon
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2189-2192
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    • 1998
  • The objective of this paper is, based upon the principles of artificial life, to induce emergent behaviors of multiple autonomous mobile robots which form from simple local rules to complex global intelligence. Here, we propose an architecture of neural network learing with reinforcement signals which perceives the neighborhood information and decides the direction and the velocity of movement as mobile robots navigates in a group. As results of the simulations, the optimum weights are obtained in real time, which not only prevent from the collisions between agents and obstacles in the dynamic environment, but also have the mobile robots move and keep in various patterns.

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Strategies for Evolution in Neural Networks based on Cellular Automata (셀룰라 오토마타 기반 신경 회로망의 진화를 위한 전략)

  • Jo, Yong-Goon;Lee, Won-Hee;Kang, Hoon
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2193-2196
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    • 1998
  • Cellular automata are dynamical systems in which space and time are discrete, where each cell has a finite number of states and updates its states by interactive rules among the cell-neighborhood. From the characteristics of self-reproduction and self- organization, it is possible to create a neural network which has the specific patterns or structures dynamically. CAM-Brain is a kind of such neural network system which evolves its structure by adopting evolutionary computations like genetic algorithms (GA). In this paper, we suggest the evolution strategies for the structure of neural networks based on cellular automata.

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Building Change Detection Using Deep Learning for Remote Sensing Images

  • Wang, Chang;Han, Shijing;Zhang, Wen;Miao, Shufeng
    • Journal of Information Processing Systems
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    • v.18 no.4
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    • pp.587-598
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    • 2022
  • To increase building change recognition accuracy, we present a deep learning-based building change detection using remote sensing images. In the proposed approach, by merging pixel-level and object-level information of multitemporal remote sensing images, we create the difference image (DI), and the frequency-domain significance technique is used to generate the DI saliency map. The fuzzy C-means clustering technique pre-classifies the coarse change detection map by defining the DI saliency map threshold. We then extract the neighborhood features of the unchanged pixels and the changed (buildings) from pixel-level and object-level feature images, which are then used as valid deep neural network (DNN) training samples. The trained DNNs are then utilized to identify changes in DI. The suggested strategy was evaluated and compared to current detection methods using two datasets. The results suggest that our proposed technique can detect more building change information and improve change detection accuracy.

A MNDB Protocol for Reliable Directional Broadcast (지향성 브로드캐스트를 위한 MNDB 프로토콜)

  • Cha, Woo-Suk;Kim, Eun-Mi;Bae, Ho-Young;Lee, Bae-Ho;Cho, Gi-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.11 s.353
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    • pp.118-127
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    • 2006
  • The wireless transmission medium inherently broadcasts a signal to all neighbor nodes in the transmission range. Existing asynchronous MAC protocols do not provide a concrete solution for reliable broadcast in link layer. This mainly comes from that an omnidirectional broadcasting causes to reduce the network performance due to the explosive collisions and contentions. This paper proposes a directional broadcast protocol by using neighborhood information in the link layer based o,1 directional antennas, named MNDB (MAC protocol with Neighborhood for reliable Directional Broadcast). This protocol makes use of neighborhood information and DMACA (Directional Multiple Access and Collision Avoidance) scheme through 4-way handshake to support a reliable directional broadcast. To analyze its performance, MNDB protocol si compared with $RMDB^{[1]}$, the protocol 2 of reference [3], and IEEE 802.11 $protocol^{[9]}$, in terms of the number of collisions, the number of dropped packets, the number of redundant packets, and broadcast delay.

A Study on the Importance of Improvement Measures for the Revitalization of Urban Regeneration Projects in General Neighborhood in Pyeongtaek City (평택시 일반근린형 도시재생사업 활성화를 위한 개선방안의 중요도에 관한 연구)

  • Kyung-Joo Kang;Jung-Min Jang
    • Land and Housing Review
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    • v.14 no.2
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    • pp.51-71
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    • 2023
  • Based on the challenges encountered in the urban regeneration projects (general neighborhood-type) of Anjung District and Sinjang District in Pyeongtaek City, this study aims to explore the key factors of improvement measures for urban regeneration projects. Using the first survey conducted among shopping mall owners, employees, and residents, this study finds a significant level of awareness and very strong needs for urban regeneration projects. On the other hand, the overall satisfaction levels are observed to be low across the three factors: social, economic, and cultural. The second expert survey and the subsequent Analytic Hierarchy Process (AHP) analysis conducted for improvement measures reveal notable discrepancies in the prioritization of factors between administrative experts and practical experts. For the importance of administrative experts, the establishment of network-type regional governance was ranked first for the importance, followed by hosting events related to the U.S. military and long-term pre-market operations, and expanding exchange and cooperation between the U.S. Forces Korea and the community. For the importance of working-level experts, hosting U.S. military-related events and long-term pre-market operations was ranked first, while supporting U.S. military-related festivals and developing local natural landscape resources was ranked second. Our findings suggest the need for proactive measures such as attracting commercial facilities to stimulate demand from both the U.S. military and local residents, thereby revitalizing general neighborhood-type urban regeneration projects, developing programs for local tourism, and operating pre-market operations in the long run. Therefore, this study highlights the importance of regional government cooperation for urban regeneration projects.

Efficient Network Selection and Vertical Handover Algorithms for Common Radio Resource Management of Heterogeneous Wireless Networks (이기종 무선망의 통합 자원관리를 위한 효율적인 네트워크 선택과 버티컬 핸드오버 알고리즘)

  • Lee, Kyung-Won;Shin, Choong-Yong;Cho, Jin-Sung
    • Journal of KIISE:Information Networking
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    • v.36 no.3
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    • pp.163-172
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    • 2009
  • Various terminals equipped with multiple interfaces may receive services from wireless networks when they pass through the overlaid heterogeneous networks, and thus the vertical handovers across the wireless networks increases, which will become a big problem in the network resource management. This problem can be efficiently solved by common radio resource management (CRRM). In this paper, we propose two operation algorithms based on network selection jointly with vertical handover as the key CRRM strategies. When a new user tries to get services, the CRRM can choose the best target network according to the proposed Integrated Network Selection Algorithm. When the network cannot satisfy the request from the new users, the proposed Integrated Vertical Handover Algorithm moves existing users to neighborhood networks to accommodate new users. The performance of the proposed algorithms has been validated through extensive simulations.

The Evaluation and the Classification of Zones for Setting Additional Green Spaces (녹지 잠재 영향권역 설정을 통한 녹지단절구역 분류 및 우선순위 선정)

  • Sagong Jung-Hee;Ra Jung-Hwa
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.2 s.109
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    • pp.1-15
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    • 2005
  • The purpose of this paper is to classify zones disrupting green spaces in city and to evaluate of their grades. The results are as follows; L There were 158 green spaces in Dalsu-gu. The 158 green spaces were classified 4 patterns and minutely classified into 9 types. The area of the 'nature park' type was turned out to be $70.1\%$ of the total area of green spaces in Dalsu-gu, then the type was considered as a important part of the green-network in Dalsu-gu. The 9 types such as 'nature park', 'river', 'neighborhood park' and so on were analysed with ecological indexes. 2. Based on the ecological indexes of 'ratio of the green space', 'features of the surrounding matrix' and 'travel distance of the wildlives' , zones disrupting green spaces were ranging widely and re-divided to 236 sectors. 3. The analysis results for classifying the grades were that grade I appeared over industrial complex and housing complex widely. On the other side, grade II and III appeared around or between nature park and neighboring park Consequently, it was necessary to consider the grade and make zones disrupting green spaces into green space for improving green network.

Study on AMI System based on IEEE 802.11s Mesh Technology (IEEE 802.11s 무선메쉬 기반 AMI 시스템에 관한 연구)

  • Kim, Younghyun;Myoung, No-Gil;Kim, Myong-Soo;Lee, Sang-Youm
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.9
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    • pp.100-106
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    • 2013
  • AMI enables bi-directional exchange of information between utilities and consumers in order to maximize energy efficiency. To enable the AMI, it is essentially required to construct stable communication networks. This paper shows the AMI system based on IEEE 802.11s as one of the communication methods. Experimental results show that the wireless mesh network technology achieves a stable communication performance over a wide coverage.

Transient State Analysis of Network Connected to Wind Generation System (풍력발전시스템이 연계된 계통의 과도상태해석)

  • Kim, Se-Ho
    • Journal of the Korean Solar Energy Society
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    • v.23 no.3
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    • pp.29-35
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    • 2003
  • Generator for wind power can be either synchronous or asynchronous (induction) types. Induction and synchronous generators behave in a different way when subjected to severe faults. Induction generators does not have an angle stability limit and short circuit in the neighborhood of an Induction generator causes the demagnetization of the machine when the fault is cleared, the voltage raises slowly, while the grid contributes with reactive power to the generator and the magnetic flux recovers. On the other hand in the synchronous generators the recovery of the voltage is immediate, since the excitation of the rotor angle comes from an independent circuit. This paper shows the result of the transient state analysis in the network connected to wind generation system Several case studies have been conducted to determine the effect of the clearing time of a fault on the network stability. It has been found that the critical clearing time can be as low as 61ms in the case of induction generator compared to 370ms in the case of synchronous generator.