• KSCI Review
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• v.14 no.2
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• pp.235-244
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• 2006

This paper attacked the unknown DoS which mixed a DoS attack, Worm and the Trojan horse which used IP Source Address Spoofing and Smurf through the SYN Flooding way that UDP, ICMP, Echo, TCP Syn packet operated. the applications that used TCP/UDP in VoIP service networks. Define necessity of a Dynamic Update Engine for a prevention, and measure Miss traffic at RT statistics of inbound and outbound parts in case of designs of an engine at IPS regarding an Self-learning module and a statistical attack spread. and design a logic engine module. Three engines judge attack grades (Attack Suspicious, Normal), and keep the most suitable filtering engine state through AND or OR algorithms at Footprint Lookup modules. A Real-Time Dynamic Engine and Filter updated protected VoIP service from DoS attacks, and strengthened Ubiquitous Security anger, and were turned out to be.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.165-174
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• 2006

This paper attacked the unknown DoS which mixed a DoS attack, Worm and the Trojan horse which used IP Source Address Spoofing and Smurf through the SYN Flooding way that UDP, ICMP, Echo, TCP Syn packet operated, the applications that used TCP/UDP in VoIP service networks. Define necessity of a Dynamic Update Engine for a prevention, and measure Miss traffic at RT statistics of inbound and outbound parts in case of designs of an engine at IPS regarding an Self-learning module and a statistical attack spread, and design a logic engine module. Three engines judge attack grades (Attack, Suspicious, Normal), and keep the most suitable filtering engine state through AND or OR algorithms at Footprint Lookup modules. A Real-Time Dynamic Engine and Filter updated protected VoIP service from DoS attacks, and strengthened Ubiquitous Security anger, and were turned out to be.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.4
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• pp.239-250
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• 1993

The dynamic resilient modulus tests to determine the $M_R$ of the soils require expensive equipments and well trained personnels to obtain reliable test results. These problems inherent in the dynamic resilient modulus testing have been realized as major negative factors to hinder the $M_R$ test from being practically implemented as a routine test. In this regard. it is highly desirable to develop a simpler alternative testing method incorporating inexpensive equipments and easy-to-perform testing procedures. Developed in this study is an alternative $M_R$ test method based on statically repeated loading scheme utilizing the standard static triaxial test equipments. Applicability and limitations of the developed static $M_R$ testing method are investigated for typical subgrade soils in Korea.

• KIISE Transactions on Computing Practices
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• v.21 no.3
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• pp.257-262
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• 2015

As software grows more complex, it contains more bugs that are not recognized by developers. Attackers can then use exploitable bugs to penetrate systems or spread malicious code. As a representative method, attackers manipulated documents or multimedia files in order to make the software engage in unanticipated behavior. Recently, this method has gained frequent use in A.P.T. In this paper, an automatic analysis method to find software security bugs was proposed. This approach aimed at finding security bugs in the software which can arise from input data such as documents or multimedia. Through dynamic taint analysis, how input data propagation to vulnerable code occurred was tracked, and relevant instructions in relation to input data were found. Next, the relevant instructions were translated to a formula and vulnerable input data were found via the formula using an SMT solver. Using this approach, 6 vulnerable codes were found, and data were input to crash applications such as HWP and Gomplayer.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2705-2708
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• 2003

In this paper, we propose a method that applies matrix decomposition technique to the connection of actuator capabilities of each robot to object acceleration limits for multiple cooperative robot systems. The robot systems under consideration are composed of several robot manipulators and each robot contacts a single object to carry the object while satisfying the constraints described in kinematics as well as dynamics. By manipulating kinematic and dynamic equations of both robots and objects, we at first derive a matrix relating joint torques with object acceleration, manipulate the null space of the matrix, and then we decompose the matrix into three parts representing indeterminancy, connectivity, and redundancy. With the decomposed matrix we derive the boundaries of object accelerations from given joint actuators. To show the validity of the proposed method some examples are given in which the results can be expected by intuitive observation.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2713-2716
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• 2003

This paper presents a dynamic manipulability analysis method of the limb moving in viscous fluid. The key idea of the presented method is that the boundary of joint velocity can be converted to the velocity-dependant dynamic manipulability polytope through the coriolis, centrifugal and drag terms in dynamic equation. The velocity-dependant dynamic manipulability polytope is added to the inertial and restoring force manipulability polytope to get overall manipulability polytope of the limb moving in the fluid Each of the torque and velocity bounds arc considered in the infinite norm sense in joint space, and the drag force of a limb moving in fluid viscous is modeled as a quadratic form An analysis example with proposed analysis scheme is presented to validate the method.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2721-2724
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• 2003

This paper deals with a manipulability analysis of multi-legged walking robots in acceleration domain, that is the dynamic manipulability analysis of walking robot. Noting that the kinematic structure of the walking robot is basically the same with that of the multiple serial robot system holding one object, the analysis method for cooperating robot is converted to that of walking robot. With the proposed method, the bound of achievable acceleration of the moving body is easily derived from the given bounds on the capabilities of Joint torques. Several walking robot examples are analyzed with proposed method under the assumption of hard contact, and presented in the paper to validate the method.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2725-2728
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• 2003

The manipulability of robot provides useful Information for the design and path planning of robots. This paper shows an influence of joint velocities to acceleration of robot end-effector using a dynamic manipulability polytope. The main idea of this paper is that the dynamic manipulability polytope of robot can be divided to three intermediate polytope, the torque-dependant polytope, velocity-dependent polytope, and gravity-dependant polytope. The velocity-dependant polytope is made from the limits of robot joint velocities while the torque-dependant polytope is made from the limits of the joint torques. Combining of these two intermediate polytopes and considering the gravity-dependant polytope, the overall dynamic manipulability polytope of robot is obtained. This investigation will be useful on the field of space robot and high-speed application.

• CDE review
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• v.2 no.1
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• pp.26-32
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• 1996

신규 차종의 개발시 차량의 exterior/interior의 design concept은 운전석주변의 driving package layout을 어떻게 구성하느냐에 따라 좌우되는 경향이 있다. 그것은 user가 그 차량의 선악의 판단함에 있어서 운전석 주변의 design 및 상품성이 큰 요인으로 작용하여 운전석 주변의 부품과 인간과의 적절한 조화를 이루어야 차량의 concept와 일치하는 최적의 design으로 user의 감성을 얻을 수 있는 것이다. 따라서 본 고에서는 신규 차종의 초기 개발 단계에서 최적의 design 및 상품성을 얻기 위한 보다 효과적인 driving package layout을 설정하기 위해 1차적 3차원 인체모형(3DM, 3-Dimensional Manikin)을 구성하고자 한다. 3DM은 human engineering에 의한 인체 치수와 각 관절의 운동방향 및 범위를 이용하여 인체의 동적 해석을 model을 도상 구현하고 이러한 3DM을 활용하여 조작성, 편의성 등의 package layout을 가시화 해 보고자 한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.351-356
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• 1993

최근의 프로세스 공업화에 있어서 생산Line의 장치나 기계류는 점차 대형화, 고속화,연속화,복잡화되고 있다. 또한, 기계가공공업,자동차공업,기계,전자부품의 가공조립등의 생산설비는 각설비가 고도로 자동화되고 있는 실정으로 공장 전체의 유기체적인 제어 및 감독을 필요로 하고 있다. 마찬가지로 기계부품제작산업도 CNC.FMS등으로 점차 조작화,자동화됨에 따라 공작기계 장치나 기계류등의 이상이나 고장으로 생산 및 품질에 미치는 영향도 종래와 비교할 수 없을 정도로 중요시 되고 있는 실정이다, 이와같이 설비의 안전성을 도모하고 고신뢰도를 부여하기위해서는 기계설비의 이상 및 고장진단이 필수적이며, 공장 자동화와 함께 공작기계자체의 고장 및 이상진단을 실시하고, 검출된 신호의 크기등으로 고장상태를 판정해야만 한다. 공작기계에서 동적인 회전시스템을 이루는 주축용베어링의 손상은 제작하고자 하는 제품의 정밀도 표면거칠기등의 저하 뿐만아니라 시스템 전체의 기능까지도 떨어뜨리는 요인이 될수 있으므로 베어링 상태를 진단하여 송상유무를 판단하는것은 필수적이라 생각된다.