• Advances in materials Research
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• 제9권3호
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• pp.189-202
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• 2020

The objective of the present work is to investigate the effect of cutting parameters (Vc, fz and ap) on tool life and the level of vibrations velocity in the machined part during face milling operation of hardened AISI 52100 steel. Dry-face milling has been achieved in the annealed (28 HRc) and quenched (55 HRc) conditions using multi-layer coating micro-grain carbide inserts. Statistical analysis based on the Response surface methodology (RSM) and ANOVA analysis have been conducted through a plan of experiments methodology using a reduced Taguchi table (L9) in order to obtain engineering models for tool life and vibration velocity in the workpiece for both heat treatment conditions. The results show that the cutting speed has a dominant influence on tool life for both soft and hard part. Cutting speed and feed per tooth is the most significant parameters for vibration levels. Comparing the experimental values with those predicted by the developed engineering models of tool life and levels of vibrations velocity, a good correlation has been obtained (between 97% and 99%) in annealed and hard conditions.

• Journal of the Korean Data and Information Science Society
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• 제10권1호
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• pp.173-191
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• 1999

본 논문에서는 시각화된 회귀진단 툴을 소개하고자 한다. 시각화된 회귀진단 툴은 회귀진단에 필요한 여러 가지 통계량들과 다양한 잔차그림을 메뉴방식에 의해서 쉽게 구할 수 있게 하였으며, 또한 프로그램을 한글화하여 일반 사용자들이 보다 쉽게 사용할 수 있도록 개발된 프로그램이다. 특히 다양한 잔차그림을 쉽게 그릴 수 있게 하여 데이터의 분석결과를 시각화할 수 있도록 하므로써 그래프를 통한 회귀분석 교육에 활용하고자 한다. 이 툴을 개발하기 위해서 시각화 언어인 델파이 3.0을 사용하였다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.247-250
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• 2007

There are three main kinds of service standards for 3G(Third-Generation) wireless communication as WCDMA, CDMA2000 and TD-SCDMA(Time Division-Synchronous Code Division Multiple Access). Compare with WCDMA and CDMA2000, TD-SCDMA system has distinguished technical characters. It is a TDD(Time Division Duplexing) based technology and deploys several advanced but in some respects complex technologies such as smart antenna, joint-detection and baton-handoff, etc. Therefore to analyze and design TD-SCDMA wireless network, it needs more efficient and systematic simulation tool. General simulation tool has so many analysis functions including path loss prediction, capacity and coverage analysis. For more suitable for TD-SCDMA, new additional technologies have to be implemented in simulation tool. Especially as the wireless network highly advancing focused on data service, it more needs to research and develop on the reliability of the simulation tool. In this paper, to give the concrete process and skill about how to implement TD-SCDMA simulation tool, we define the kinds of simulation tool and list basic analysis functions available for TD-SCDMA network design at first. And then we explain how to consider the effects of new technologies of TD-SCDMA and give the solutions about theses considerations.

• 한국생산제조학회지
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• 제19권5호
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• pp.596-602
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• 2010

In this study, a fmite element model was developed for analysis of feeding a structure in open loop control The finite element analysis (FEA) can simulate dynamic behavior of the structure of a machine tool rapidly traveling with a screw feeding driving system. The feeding mechanism was implemented with screw element of the FEA tool used in this study. The procedure was developed for the dynamic transient FEA. First, motion parameters such as jerk and velocity were introduced for the structure to be fed in open loop control When its traveling distance was determined, set-points for the distance were generated based on the motion parameters. The set-points were applied to the FE model constructed for the traveling structure. The FEA was executed and evaluated. In this study, the FEA procedure was applied to the column of a machine tool and the dynamic behavior of the column was evaluated. The FEA helps in evaluation of the motion characteristics of a structure. The convergence time of the structure vibration posterior to feeding termination can be estimated and the stiffness of the flexible structure is also evaluated against jerk, and acceleration. It provides the feeding force which is helpful in selection of the feeding motor.

• International Journal of Precision Engineering and Manufacturing
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• 제6권1호
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• pp.65-72
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• 2005

Drilling process is one of the most common, yet complex operations among manufacturing processes. The performance of a drill is largely dependent upon drilling forces, Many researches focused on the effects of drill parameters on drilling forces. In this paper, an effective theoretical model to predict thrust and torque in drilling is presented. Also, with the predicted forces, the stress analysis of the drill tool is performed by the finite element method. The model uses the oblique cutting model for the cutting lips and the orthogonal cutting model for the chisel edge. Thrust and torque are calculated analytically without resorting to any drilling experiment, only by tool geometry, cutting conditions and material properties. The stress analysis is performed by the commercial FEM program ANSYS. The geometric modeling and the mesh generation of a twist drill are performed automatically. From the study, the effects of the variation of the geometric features of the drill and of the cutting conditions of the drilling on the drilling forces and the stress distributions in the tool are calculated analytically, which can be applicable for designing optimal drill geometry and for improving the drilling process.

• 한국철도학회논문집
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• 제12권4호
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• pp.450-456
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• 2009

최근의 컴퓨터 기술의 발달에 따라 열차제어시스템들이 컴퓨터 소프드웨어에 의존성이 더옥 증가되고 있으며, 이에 따라 이러한 열차제어시스템 소프트웨어의 안전성과 선뢰성에 대한 테스팅이 더욱 증요하게 되었다. 본 논문에서는 이러한 열차제어시스템 소프트웨어를 위한 Metrics 분석 자동화 도구를 제안하였으며, 또한 구현결과를 제시하였다. S/W Metrics는 철도시스템 소프트웨어관련 국제표준에서 언급되고 있는 Metrics를 대상으로 하였으며, 철도 소프트웨어 소스코드의 Metrics를 자동으로 분석하여 그 결과를 사용자에게 다양한 형태로 제시할 수 있도록 구현하였다. 자동화 도구는 열차제어시스템 소프트웨어 평가단계에서도 활용될 수 있고 또한 소프트웨어 개발단계에서도 유용하게 활용될 수 있을 것으로 예상된다.

• 대한안전경영과학회지
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• 제19권4호
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• pp.133-140
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• 2017

The Ministry of Science, ICT and Future Planning made law for Pre-Hazard Risk Analysis in December 31, 2014 to protect researchers from continuing accidents in laboratory. Conducted before an experiment, Pre-Hazard Risk Analysis finds hazards of the experiment and rules to manage the hazards.So the Pre-Hazard Risk Analysis can support laboratory safety system by prevent accidents in laboratory. Pre-Hazards Risk Analysis is newly created system so that executors need Guidelines to perform this analysis properly. This study is to develop guide tool for Pre-Hazard Risk Analysis by analyzing other risk assessment systems; PSM, Off-site Consequence Assessment, laboratory safety system. Also, this study suggested how to establish database for Pre-Hazard Risk Assessment by analyse KRAS.

• 한국통신학회논문지
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• 제38C권5호
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• pp.420-427
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• 2013

최근 안전한 소프트웨어 개발을 위해 소프트웨어의 소스코드를 분석하여 보안취약점의 원인이 되는 소프트웨어 보안약점을 식별해 주는 정적분석 도구가 많이 활용되고 있다. 최적의 정적분석 도구를 선택하기 위해서는 도구가 보유한 보안약점 규칙 및 분석기능이 중요한 요소가 된다. 따라서, 본 논문은 정적분석 도구가 보유한 규칙 및 분석 성능을 평가하기 위해 개발한 시험코드를 제시하고자 한다. 시험코드는 SQL 삽입 등 43개 보안약점이 존재하는 소스코드로 정적분석 도구가 보유한 보안약점 규칙과 이를 기반으로 한 도구의 분석기능의 적절성을 평가하기 위해 사용될 수 있다.

• 정보보호학회논문지
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• 제26권5호
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• pp.1185-1189
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• 2016

현대 사회에서는 임베디드 장비의 수가 급증하고 있다. 그러나 급증하는 임베디드 장비와 동시에 악용 가능한 취약점과 백도어 등이 계속해서 발견되고 있어 이에 대한 분석의 필요성이 끊임없이 제기되고 있는 실정이다. 이에 따라 본 논문에서는 임베디드 장비 펌웨어의 정적 분석 환경 구축을 위해 필요한 기준 주소 정보를 추출하는 도구를 개발하고, 이를 사용하여 정적 분석 환경을 구축함으로써 펌웨어 내부 문자열의 파싱과 참조를 가능하게 하고, 증가된 함수식별 개수 등을 통해 도구의 타당성을 증명한다.

• 한국정밀공학회지
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• 제15권8호
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• pp.116-125
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• 1998

In this paper, main target is to select parameters for prediction of tool wear and detection of tool fracture. The research about choosing parameter for prediction of tool wear is done by using force ratios. Also current sensor, tool-dynamometer, and accelerometer are used for researching detection method of tool fracture. Experiment is done using Taguchi's method in medium machining conditions. Parameter which is best for prediction of tool wear and detection of tool fracture by deviation analysis is selected. In this paper, tool wear means flank wear.