• Title/Summary/Keyword: Discovery

Search Result 3,511, Processing Time 0.024 seconds

The study of instruction on permutation and combination through the discovery method (발견을 통한 순열과 조합 지도방안 연구)

  • Kim, Mi-Jeong;Kim, Yong-Gu;Jung, In-Chul
    • The Mathematical Education
    • /
    • v.48 no.2
    • /
    • pp.113-139
    • /
    • 2009
  • In this study, we apply the discovery method in the instruction of Permutation and Combination, and examine the effect upon the student's emotion after the instruction change. The research progressed through the instruction by the discovery method for two students of highschool Y. This research has been done for about one and half year from November 2006 to February 2008. We draw our research results through a series of processes consisted of videotaping a classroom activities, recording interview details and writing an observation diary, with the aim of the experimental instruction. In the end, we get to the conclusion that students showed a strong positive attitude on the discovery instructional method and that diverse discovery method has supplementary relation in classwork.

  • PDF

Supporting Mobile IP in Ad Hoc Networks with Wireless Backbone (무선 백본 기반 Ad Hoc 네트워크에서의 Mobile IP지원)

  • 신재욱;김응배;김상하
    • Proceedings of the IEEK Conference
    • /
    • 2003.11c
    • /
    • pp.223-226
    • /
    • 2003
  • In this paper, we propose new agent discovery and route discovery schemes to support Mobile IP (MIP) in Ad Hoc networks with wireless backbone. The wireless backbone consisting of stationary wireless routers and Internet gateways (IGs) is a kind of wireless access network of IP-based core network. The proposed scheme utilizes favorable features of wireless backbone such as stable links and no energy constraints. In the agent discovery scheme, backbone-limited periodic Agent Advertisement (AA) and proxy-AA messages are used, which reduce network-wide broadcasting overhead caused by AA and Agent Solicitation messages and decentralize MIP processing overhead in IGs. In order to reduce delay time and control message overhead during route discovery far the destination outside Ad Hoc network, we propose a cache-based scheme which can be easily added to the conventional on-demand routing protocols. The proposed schemes can reduce control overhead during agent discovery and route discovery, and efficiently support MIP in Ad Hoc network with wireless backbone.

  • PDF

Implementation of Policy Based MANET Management System based on Active PDP Discovery (Active PDP Discovery에 기반한 정책 기반 MANET 관리 시스템 구현)

  • Huh, Jee-Wan;Song, Wang-Cheol
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.10 no.11
    • /
    • pp.3176-3182
    • /
    • 2009
  • The PBNM on MANET is being researched to ensure the reliability and efficiency between mobile nodes. Therefore, it is essential to determine the cluster effectively which will perceive the movements of nodes and distribute the policies. In PBNM mechanism, to determine the node cluster for PDP and manage PEP nodes, Active PDP Discovery Protocol is proposed as a mechanism which is more efficient than preexistent techniques. While k-hop cluster selects the PEP nodes which PDP node manages, Active PDP Discovery actively selects the PDP node among the moving PEP node. This method prevents orphan nodes that are not connected to PDP and reduces continual broadcasting messages. This paper implements Active PDP Discovery which determines cluster in the real networks and analyzes its capability, expanding COPS-PR to detect the movement of nodes and adding MNL to PDP node.

Probabilistic Neighbor Discovery Algorithm in Wireless Ad Hoc Networks (무선 애드혹 네트워크에서의 확률적 이웃 탐색 기법)

  • Song, Taewon;Park, Hyunhee;Pack, Sangheon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.39B no.9
    • /
    • pp.561-569
    • /
    • 2014
  • In wireless ad hoc networks, neighbor discovery is essential in the network initialization and the design of routing, topology control, and medium access control algorithms. Therefore, efficient neighbor discovery algorithms should be devised for self-organization in wireless ad hoc networks. In this paper, we propose a probabilistic neighbor discovery (PND) algorithm, which aims at reducing the neighbor discovery time by adjusting the transmission probability of advertisement messages through the multiplicative-increase/multiplicative-decrease (MIMD) policy. To further improve PND, we consider the collision detection (CD) capability in which a device can distinguish between successful reception and collision of advertisement messages. Simulation results show that the transmission probabilities of PND and PND with CD converge on the optimal value quickly although the number of devices is unknown. As a result, PND and PND with CD can reduce the neighbor discovery time by 15.6% to 57.0% compared with the ALOHA-like neighbor discovery algorithm.

A Study on Functional Requirements for the Establishment of Evidence Values of Electronic Records Focused on eDiscovery (전자기록의 증거적 가치 수립을 위한 기능요건에 관한 연구: 미국 eDiscovery 적용을 중심으로)

  • Choi, Kippeum;Lee, Gemma;Oh, Hyo-Jung
    • Journal of the Korean Society for information Management
    • /
    • v.38 no.2
    • /
    • pp.201-226
    • /
    • 2021
  • Discovery's collection was originally paper documents, but with the advent of the digital age, its collection expanded. Resolving the issue of ESI has now become important in litigation. Therefore, this study analyzes the requirements of each domain for electronic records to be recognized as evidence. It also explained the factors that should be considered in record management. In addition, eDiscovery in the United States was selected as an advanced case to utilize records as evidence. This study investigated the Commentary on Legal Holdings: The Trigger & The Process and analyzed which functions must be considered in order for electronic records to be preserved as evidence. To this end, we analyze the functional requirements of the eDiscovery solution. Through this, necessary functional requirements are derived to help implement the system in preparation for eDiscovery.

Multiple token-based neighbor discovery for directional sensor networks

  • Nagaraju, Shamanth;Gudino, Lucy J.;Sood, Nipun;Chandran, Jasmine G.;Sreejith, V.
    • ETRI Journal
    • /
    • v.42 no.3
    • /
    • pp.351-365
    • /
    • 2020
  • Directional sensor networks (DSNs) can significantly improve the performance of a network by employing energy efficient communication protocols. Neighbor discovery is a vital part of medium access control (MAC) and routing protocol, which influences the establishment of communication between neighboring nodes. Neighbor discovery is a challenging task in DSNs due to the limited coverage provided by directional antennas. Furthermore, in these networks, communication can only take place when the beams of the directional antennas are pointed toward each other. In this article, we propose a novel multiple token-based neighbor discovery (MuND) protocol, in which multiple tokens are transmitted based on an area exploration algorithm. The performance of the protocol is evaluated using the Cooja simulator. The simulation results reveal that the proposed MuND protocol achieves lower neighbor discovery latency, with a 100% neighbor discovery ratio, and has a relatively low communication overhead and low energy consumption.

Implementation of an Efficient Service Discovery Protocol for Directory Facilitator Based on CALM Agent (CLAM 에이전트 기반 Directory Facilitator를 위한 효율적인 서비스 디스커버리 프로토콜 구현)

  • Lee, Seung-Hyun;Shin, Dong-Ryeol;Jang, Kyung-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.11 no.6
    • /
    • pp.275-282
    • /
    • 2011
  • Current service discovery protocols such as UPnP, Jini, SLP provide the basic function which is message exchange pattern, service representation and description, in service discovery. They does not guarantee service interoperability among service discovery. Therefore, in this paper, we design and implement CLAM (Component-based Autonomic Layered Middleware) agent platform to enable an efficient service discovery through extension of DF agent function in FIPA-compliant specification. Also, we propose an efficient service discovery mechanism using DHT-Chord algorithm to guarantee scalability and interoperability in DF agent.

Evaluating and Comparing the Search & Discovery Features: Focusing on the Public Libraries OPACs and the Internet Bookstores (탐색과 디스커버리 기능 평가 연구 - 공공도서관 OPAC과 인터넷 서점을 중심으로 -)

  • Han, Seunghee
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.50 no.1
    • /
    • pp.493-511
    • /
    • 2016
  • Discovery is an emerging concept to enhance the search capabilities of library resources with the Next Generation Library Catalog. This paper defined the Discovery feature based on the information search behavior, and then derived the elements that make up its function. After that, the 11 regional representatives libraries' OPACs and 3 Internet bookstores are evaluated and compared against Search & Discovery capabilities. As a result, the Internet bookstores were superior to the libraries' OPACs for all the elements that make up the Discovery functions. This study verified that the public libraries OPACs are still concentrating on known item search, and it is hard for the users to meet a serendipity which is gained through the Discovery functions.