• Tunnel and Underground Space
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• v.14 no.6 s.53
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• pp.411-422
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• 2004

Sinkhole subsidence occurs over abandoned mine workings and can be detrimental to human lives, damage to properties and other surface structures. In this study, simulation of sinkhole development process is performed using special finite element procedure. Especially, creation of mine voids due to roof falls and generation of goaf from broken rocks are simulated using active-passive-active finite elements. An active or solid element can be made passive or void once the tensile failure criterion is satisfied in the specified sinkhole formation zone. Upon completion of sinkhole development process, these passive elements in again be made active to simulate goal region. Several finite element models are analyzed to evaluate the relationships between sinkhole formation with width of gallery. depth of mine, roof condition and bulking factor of roof rocks. This study demonstrates that the concept of passive elements in numerical analysis can be used effectively for analyzing sinkhole formation or roof fall phenomenon in general.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1591-1597
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• 2003

In this paper, Active Resonator Oscillator using active inductor and active capacitor with HEMTs(agilent ATF­34143) is designed and fabricated. Active inductor with ­25$\Omega$ and 2.4nH in 5.5GHz frequency band and Active capacitor with ­14$\Omega$ and 0.35pF is designed. Active Resonator Oscillator for LO in ISM band(5.8GHz) is designed with active inductor and active capacitor. Active Resonator Oscillator has been simulated by Agilent ADS 2002C. Active Resonator oscillator implemented on the substrate which has the relative dielectric constant of 3.38, the height of 0.508mm, and metal thickness of 0.018mm. This Active Resonator Oscillator shows the oscillation frequency of 5.68GHz with the output power of ­3.6㏈m and phase noise of ­81㏈c/Hz at the offset frequency of 100KHz.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.6
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• pp.3-12
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• 2005

To provide visitors with the various services, Many web sites distribute many ActiveX controls to them because ActiveX controls can overcome limits of HTML documents and script languages. However, PC can become dangerous if it has unsecure ActiveX controls, because they can be executed in HTML documents. Nevertheless, many web sites provide visitors with ActiveX controls whose security are not verified. Therefore, the verification is needed by third party to remove vulnerabilities in ActiveX controls. In this paper, we introduce the process and the technique to fad vulnerabilities. The existing proof codes are not valid because ActiveX controls are different from normal application and domestic environments are different from foreign environments. In this paper, we introduce the technique to prove vulnerabilities in ActiveX control.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.1
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• pp.13-20
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• 2006

Active packaging is one of the innovative concepts which actively change the condition of the packaged products. Active packaging technique controls the environment inside the packaging in order to extend the shelf life of the product and improve its quality or safety. Active packaging are based on major contents of scavenging concepts, releasing concepts, and other active packaging concepts such as removal or indicating systems. In recent years, experimental developments using active packaging concepts between polymeric packaging materials and the contact surfaces of food products are widely studied in order to make extensive commercial applications. Well-developed packaging markets in USA, Japan, and Europe are already being successfully applied in active packaging concepts. This paper reviews the concepts of active packaging and current information of active packaging technologies. The status of domestic technologies in active packaging were analyzed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.938-944
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• 1994

Active damping has been shown to offer increased suspension performance in terms of vehicle isolation, suspension packaging, and road-tire contract force. Many semi-active damping strategies have been introduced to approximate the response of active damping with the modulation of passive damping parameters. This study investigates the characteristics of semi-active suspension control through the simulation of passive, skyhook active, and semi-active damping models. A quarter car model is studied with the conrolled damping replacing both passive and active damping. A new semi-active scheme is suggested to eliminate the abrupt changes in semi-active damping force. It is shown that the new strategy performs almost identically to the so called "force controlled" semi-active law without steep changes in damping force or body acceleration.eleration.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10c
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• pp.144-146
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• 2000

전자 상거래를 지원하는 클러스터 컴퓨팅 시스템은 장시간에 걸쳐 대량의 트랜잭션을 처리해야 하며, 빈번한 통신두절 및 데이터 유실 가능성이 높기 때문에, 현재 이와 같은 시스템의 가용도를 개선.확보하기 위한 연구가 활발하다. 본 논문에서는 Active/Active 클러스터 시스템의 소프트웨어적인 결함 발생을 미연에 방지할 수 있는 능동적 결함허용 기법인 소프트웨어 재활(rejuvenation) 방법을 적용하여, 가용도 및 시스템 가동 중단으로 인한 손실비용에 계산하였으며, 이를 통하여 소프트웨어 재활을 하면 할수록, Active/Active 클러스터 시스템의 가용도와 손실비용이 모두 감소하는 추세에 있음을 확인하였다.

• The KIPS Transactions:PartC
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• v.11C no.3
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• pp.361-370
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• 2004

All active nudes which have no physically direct connection with each other in If network must be able to compose and manage network topology Informations. Besides one active program can be performed by the active nodes when every active packet for this program is transmitted without any loss of packets. Also the active packets should be transmitted effectively to minimize the transmission delay and securely from threatens. In this thesis, the discovery scheme of active nodes is adapted for active nodes in IP networks to compose and manage the topology information. The scheme for the efficient, reliable and secure transmission of active packets is also proposed. The sequence number is assigned to every active packet. If a receiver detects the loss of active packet checking the sequence number, the receiver requests the retransmission of the lost packet to the previous active node. kiter receiving an active packet and adapting security and reliability schemes, intermediate active nodes not only copy and send the Packet Instantly but also apply some suity mechanisms to it. And the active packet transmission engine is proposed to provide these transmission schemes The simulation of the adapted active node discovery scheme and the proposed active packet transmission engine is performed. The simulation results show that the adapted active node discovery scheme is efficient and the proposed active engine has the low latency and the high performance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.6
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• pp.113-119
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• 2009

In recent years, to provide visitors with the various and dynamic services, many ActiveX Controls are developed and distributed in most of the web sites such as e-Government Internet banking Portal in Korea. However, unsecure ActiveX Controls may be critical security threats on Internet User. Although hacking incidents increase sharply for these vulnerable ActiveX Controls, there are not enough national security actions or policies. Thus, in this paper we propose the technical method to design 'Security model for ActiveX Control Managemnet through Security Authentication' to be able safe and useful security management in three aspects of development distribution using.

• Proceedings of the Korea Association of Information Systems Conference
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• 2003.05a
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• pp.253-270
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• 2003

본 연구는 마이크로소프트사가 개발한 ActiveX 콘트롤 기술을 이용하여 동적인 홈페이지를 제작하는 사례를 설계하고 구현 해 봄으로써 ActiveX 콘트롤의 사용가치와 이의 활용방안을 알아보고자 함에 있다. 이를 위해 첫째, 비주얼베이직과 자바를 이용한 웹프로그래밍 기술과 ActiveX 콤포넌트의 기능을 알아보고 둘째, 웹프로그래밍의 역사와 ActiveX프로그램과의 관련성과 현재 대두되고 있는 XML웹서비스기술과의 비교를 통하여 웹프로그래밍기술을 이해하고 셋째, ActiveX콘트롤 패드를 이용하여 실제로 동적홈페이지를 구성하는 사례를 설계하고 구현해 봄으로써 이의 활용가치를 알아보고자 하였다. 연구결과 자바 애플릿에 대응하는 기술로 마이크로소프트가 OLE기술을 확장하여 만든 ActiveX콘트롤은 프로그램의 재사용, 개발시간단축과 프로그램의 기능과 품질향상에 기여하여 인터넷 내지 인트라넷용 프로그램개발 등에 쉽게 이용될 수 있는 가능성을 보여 주었으나 플랫폼 독립적이지 못하고 윈도우에서만 사용 가능한 제한점을 보여주었다.

• The KIPS Transactions:PartC
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• v.8C no.2
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• pp.173-181
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• 2001

하드웨어 기술의 발전으로 인해 컴퓨터 하드웨어의 결함 발생률은 상수 값이거나 점차 작아지는 경향이 있다. 반면에 하드웨어에 탑재된 소프트웨어의 복잡성 및 크기는 이전에는 상상할 수 없을 정도로 방대해져가고 있기 때문에, 소프트웨어의 결함 발생으로 인한 컴퓨터 시스템의 장애 발생 가능성은 점차 더 높아지고 있다. 본 논문에서는 Active/Active 클러스터 시스템의 가용도 개선을 위해서 소프트웨어적인 결함 발생을 미연에 방지할 수 있는 능동적 결함허용 기법인 소프트웨어 재활(rejuvenation) 방법에 대하여 연구하였다. 소프트웨어 재활 과정 및 여분서버로 작업전이(switchover) 과정을 semi-Markov 프로세스로 모델링 한 후, 수학적 분석을 통해 구한 Active/Active 클러스터 시스템의 bud형 상태 확률을 이용하여, 다양한 운영 조건하의 가용도 및 손실비용을 계산하였으며, 이를 통하여 소프트웨어 재활을 통한 Active/Active 클러스터 시스템의 가용도 개선 가능성을 확인하였다.