• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.19-26
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• 2003

An oscillating digger mechanism was designed, constructed. and tested. The mechanism is consisted of a six-bar linkage, one four-bar linkage was fer the digger blade and the other one fur variable soil-crop separation. Experimental variables were amplitude(3, 6, 9 mm). frequency(11.2, 14.9. 17.0 Hz), and forward speed of tractor(0.91, 1.13, 1.56 km/h). Each combination of these variables was replicated three times to measure the draft and torque for power requirement evaluation. and the broken-up soil height on the soil separation sieve mechanism. Four parameters λ(the ratio of vibration speed to forward velocity), p(the ratio of vibration acceleration to forward velocity), K(the ratio of vibration acceleration to gravitational acceleration), and T(the product of λ and K) were induced from three experimental variables: amplitude, frequency, and tractor speed. And the power requirement and soil separation ability were analyzed by regression. Though λ and K were known to be the representative parameters. T was the most moderate one to explain draft. torque. and soil separation in this study. It was estimated that the T equal to or greater than 2.4 was the minimum recommended value. Figure 18 would be useful fir the selection of amplitude. frequency, or operating tractor speed once any two variables are known.

• Journal of the Korean Society of Systems Engineering
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• v.8 no.1
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• pp.21-28
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• 2012

Development of the system that has required performance is the most important figure and that is the key of project succeed. In order to perform that, systems engineering has come to the fore as a solution. In each step of system engineering process, particularly, requirement analysis and derivation, logical solution, architecture design step are known to affect many of the function and efficiency. Of these, this paper focus on architecture design. We introduce methodology for physical architecture design by applying DSM(Design Structure Matrix) methodology which is based on result of logical solution from MBSE methodology.

• Journal of the Korean Society of Safety
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• v.21 no.2 s.74
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• pp.98-106
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• 2006

The substructure of temporary bridges used during the construction period of main bridges needs to be simple and strong at the same time so that it doesn't block running water. When the water flow is hindered by sub-structure of the bridges, as it happens when H beams with bracing are used, either the water floods or the bridge gets damaged. Therefore, using round beams for the substructure and connect them together is a preventive choice considering the intensive raining in the summer. The bridges using round beams for the substructure have also benefited by fast construction because of fewer bracing and in-situ welding. Because the round-pile-connecting method is relatively new, the safety evaluation of the constructed bridge is an essential procedure before being used in the field. The field evaluation of a bridge including the vehicle loading test and moving load analysis has been conducted and the results showed the safety requirement is satisfied.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1080-1090
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• 2010

A study for improvement of credibility on test & evaluation result of interoperability in battle management information system which focused in C4I systems is very essential in rapid change of battle field environment. Realization of effective operation process with integration of developed IT also core factor for reducing of operational response time such as information gathering from sensor to shooter, time for commander's decision making. Therefore, by required to meet of high technical T&E, meet of complex software's user requirement, long-term system development period, system integration ability's request by various linkage of systems, it is high a M&S dependency to optimal performance, interpoerability's guarantee. Especially credibility on test & evaluation using M&S is very important. This paper will propse a VV&A applied methods using other VV&A case to improve credibility of M&S on test & evaluation.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.11a
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• pp.1482-1485
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• 2012

연구개발 수명주기의 첫 단계에서 도출되는 요구사항은 수명주기 전 단계 수행의 가이드라인 및 기준이 되는 매우 중요한 요소이다. 본 논문은 표준 및 지침을 분석, 정리하여 국방무기체계 개발을 위한 요구사항의 개발 및 관리 프로세스를 정립하고 이를 제대로 적용할 수 있도록 전산지원도구(DOORS)를 개선한 것을 사례를 들어 보여준다.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.1
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• pp.50-57
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• 2021

Engine cool down process is necessary for the liquid rocket engines using cryogenic propellants in order to meet the requirement of engine inlet temperature. This paper evaluates the cool down characteristics of oxidizer supply pipeline and engine in prechill process prior to the engine firing tests, and calculate the quantity of liquid oxygen consumption.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.282-291
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• 2010

In line with current speed-up of railroad, a slab track has been increasingly adopted in a bid to secure the safety of track structure as well as to reduce the maintenance cost, and furthermore, the need for commercialization of domestically-developed swing-nose crossing turnout on slab track has been on the rise. For commercialization of swing-nose crossing turnout on slab which was developed in Korea, a technical and systematic performance evaluation system, considering local environment, shall be established and then the performance evaluation shall be accordingly implemented. This paper was intended to summarize the performance evaluation system, referring to the data available at home and abroad and the results of performance evaluation for domestically-developed swing-nose crossing turnout on slab track carried out to date based on that system. A performance evaluation system comprises the technical requirement appropriateness evaluation(component performance evaluation and design verification), laboratory test and on-site test. For domestically-developed swing-nose crossing turnout on slab track, appropriateness evaluation and laboratory test have been completed and the on-site test of those installed on the 2nd phase of Kyung-Bu HSR is underway now.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.4
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• pp.493-498
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• 2011

In this paper, Transmission performance over MANET(Mobile Ad-hoc Networks) under DDoS Intrusions is evaluated. Intrusion counterplan requirement, which have to be used for MANET under DDoS intrusions, is suggested through this evaluation. VoIP simulator based on NS-2 network simulator is used for performance measurement. MOS, network delay, packet loss rate and call connection rate is measured with this simulation. Finally, requirement of intrusion continuing time shorter then 10 seconds is suggested for VoIP service over MANETs under DDoS intrusions.

• Journal of Korea Multimedia Society
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• v.6 no.4
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• pp.723-735
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• 2003

This research focuses ell an approach for the building of a requirements model for the development of large-scale information systems. It will suggest a set of requirements engineering processes as a procedure of the implementation for building the requirements model. It will also emphasise the evaluation requirements model aimed to refine and complete the requirements model by the different user groups as a cross reference. This paper provides an advanced user-construction requirements within the Event Flow Diagram as a set of requirements engineering process.

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.1894-1903
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• 2003

It is necessary to have a dummy that describes the anthropometry of a victim with accuracy. This study presents three scaled side impact dummies constructed for the use of MADYMO. They represent five, fifty and ninety-five percentile Korean males ranged from the age of 25 through 39. Thirty-five anthropometric data were used to scale input files required for MADYSCALE. Geometries, inertia, joints and other parameters for dummies were scaled based on the configurations of EuroSID-1. This study proposes the lateral impact response requirements for head, thorax and pelvis of Korean side impact dummies. A lateral drop impact test was conducted for the head at the height of 200 mm. Lateral pendulum impact tests were also carried out for thorax and pelvis at three specific impact velocities. All these test results were obtained from simulation based on MADYMO. All the procedures of the three tests followed the requirement of ISO/TR 9790.