• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.5C
• /
• pp.422-434
• /
• 2002

We propose 3-layered hierarchical fiber-optic backbone transmission network composed of B-DCS, Backbone ring, Edge ring for efficient transmission of high capacity traffic and consider design method to ensure network survivability of each layer at affordable cost. Mathematical ring-construction cost minimization using MIP(Mixed Integer Programming) models results in NP-complete problem. So, it is hard to solve it within reasonable computing time. on a large-scale network. Therefore we develop heuristic algorithms solving WSCAP(Working and Spared Channel Assignment Problem) for B-DCS, MRLB(Multi-Ring Load Balancing) problem for Backbone ring, and ORLB(Overlayed Ring Load Balancing) problem for Edge ring and show their usefulness through case study.

• Convergence Security Journal
• /
• v.10 no.3
• /
• pp.29-41
• /
• 2010

Survelliance and Reconnaissance Sensor Network(SRSN) which can collect various tactical information within battlefield in real time plays an important role in NCW environment, of sensor to shooter architecture. However, due to the resource-limited characteristics of sensor nodes and the intrinsic attributes of sensor network such as wireless communication, the SRSN may be vulnerable to various attacks compared to traditional networks. Therefore, in this paper, we propose a new group key management scheme to guarantee confidentiality, integrity, availability, and authentication during the operation of the SRSN. Proposed scheme generates and distributes the group key based on the topological characteristic of the SRSN and the probabilistic key sharing. The communication cost for distributing the group key is O(logn).

• Journal of Korea Game Society
• /
• v.8 no.2
• /
• pp.47-55
• /
• 2008

This paper introduces that SSFE(Skeleton System for Facial Expression) to deform facial expressions by rigging of skeletons does same functions with 14 facial muscles based on anatomy. A three dimensional animation tool (MAYA 8.5) is utilized for making the SSFE that presents deformation of mesh models implementing facial expressions around eyes, nose and mouse. The SSFE has a good reusability within diverse human mesh models. The reusability of SSFE can be understood as OSMU(One Source Multi Use) of three dimensional animation production method. It can be a good alternative technique for reducing production budget of animations. It can also be used for three dimensional animation industries such as virtual reality and game.

• Journal of Energy Engineering
• /
• v.12 no.2
• /
• pp.109-117
• /
• 2003

Because of the difficulty of acquiring new generation sites and right-of-way, additional units have been added to the existing generation sites and the transmission system has been developed into highly meshed configuration. This structural characteristics may cause restriction on the reliable operation of power systems. In other to meet with this problem, the enhancement of system analysis techniques and establishment of appropriate measures have been required in this situation. In addition the deregulation of electric power industry in Korea would require better tools for power system analysis and control. In this paper, exciter system models, speed governor system models and PSS models of EUROSTAG for stability study are developed. Comparison with simulation results of PSS/E is performed for verification of EUROSTAG models.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2008.05a
• /
• pp.426-430
• /
• 2008

Though the air-conditioners in each train model have almost identical function, there is incompatibility between them because of their different electric capacity and parts, even spares manufactures are different in the manufactured year. It cause over cost in the maintenance and repair of the each air-conditioner. In this paper, all the air-conditioners in each train model have been classified by their capacity and features so that grasp the operation status and the repair process of the air-conditioners, and draft systematically cost-effective solutions. By finding a way to deal with the emergency repair and extending the air-conditioner life though improvement of checking up progress, increase of passenger revenue can be reached considerably.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.11
• /
• pp.5866-5871
• /
• 2013

DMSMS(Diminishing Manufacturing Sources and Material Shortage) of weapon systems is caused by required increase in system life cycle and reduction of military electronic parts market share. This problem causes serious problems about Combat readiness and Life-cycle cost. In this paper, we review the method for managing the DMSMS and then suggest effective alternatives to reduce the risk of DMSMS for weapon systems, such as systematic DMSMS management system and quantitative design refresh planning considering the DMSMS.

• The Journal of the Korea Contents Association
• /
• v.10 no.4
• /
• pp.115-122
• /
• 2010

Most of intelligent services provided today work based on the users' location. Numerous devices for indoor localization services have their own characteristic functions and operating systems, we need the interoperability and diversity of middleware to connect and control these devices. The indoor localization method using existing inertial sensors are relatively less efficient because of additional cost according to the size of space. Accordingly, the indoor user localization method proposed in this study supports integrated services using OSGi framework, an open source project, and solves problems in inertial sensor based on accurate distance to a specific object measured using ultrasonic sensor. Furthermore, it reduces errors resulting from difference in response rate by adding the reliability item.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.9
• /
• pp.1395-1403
• /
• 1993

Protocol conformance is crucial to inter-operability and cost effective computer communication. Given a protocol specification, the task of checking whether an inplementation conforms to the specification is called conformance testing. The efficiency and fault coverage of conformance testing are largely dependent on how test cases are chosen. Some states may have more one UIO sequence when the protocol is represented by FSM (Finite State Machine). The length of test sequence can be minimized if the optimal test sequences are chosen. In this paper, we construct the depth-tree to find the maximum overlapping among the test sequence. By using the resulting depth-tree, we generate the minimum-length test sequence. We show the example of the minimum-length test sequence obtained by using the resulting depth-tree.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.11
• /
• pp.5987-5992
• /
• 2013

The authors suggest the extension IFC schema of drainage facilities for the purpose of establishment the information model standard for the roads. IFC entities, types and properties for drainage facilities are defined by the analysis of road design documents for extraction physical component and design information IFC schema is able to be extended through the result of this research. Futhermore, IFC for additional road facilities is able to be used as construction process control, quantity take off, and simulation applications with the interoperability of the IFC.

• Environmental and Resource Economics Review
• /
• v.4 no.1
• /
• pp.155-196
• /
• 1994

본 연구는 두만강지역의 에너지 자원개발에 관한 연구에서 전력산업을 중심으로 다루었으며 연구범위는 연변 조선족 자치주 수도 연길과 러시아의 군사항 블라디보스톡 그리고 북한의 청진을 잇는 대삼각지대(Tumen River Economic Development Area: TREDA)로 하였다. TREDA내에 2020년의 국가별 총전력수요는 중국 9,052 Gwh, 북한 8,989 Gwh, 러시아 15,662 Gwh이며, 1991년-2020년간의 년평균 증가율은 중국 8.4%, 북한 5.9%, 러시아 3.1%로 전망된다. 따라서 발전소 건설계획은 3개국(중국-북한-러시아)전력계통연계 방안이 가장 경제적인 것으로 나타났으며, 송변전계통은 각국이 주파수가 상이하여 전력계통의 연계가 경제적, 기술적으로 타당성 검토가 곤란하나 계통연계시 기존 설비의 보완 및 설비운용면에서 제도적 보완책이 필요한 것으로 사료된다. 전기요금은 국가에서 통제, 결정하여 왔다. 그러나 두만강개발특구는 자유무역경제특구이므로 시장경제체제에 의한 발전소 건설 계획을 전제로 한 한계비용이 68원/Kwh일때 자원의 효율적 배분과 사회 후생을 극대화할 수 있다는 것이다. 단기적으로 TREDA사업초기에는 환경설비를 갖춘 재래식 석유 및 석탄화력 발전소가 투자 부담면에서 유리하나 향후 환경규제를 대비하기 위해서는 원자력발전의 건설도 환경영향을 최소화할 수 있는 방안으로 모색될 수 있을 것이다.