• 산업경영시스템학회지
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• 제21권47호
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• pp.1-10
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• 1998

Testing high reliability devices under nomal operating condition is difficult, because the devices are not likely to fail in the relatively short time available for tests. For most applications it is necessary to accelerate the causes of failure by increasing a stress above its nomal value. Previous accelerated life test(ALT) plans have shown how to find optimum allocation, lowest stress and sample size subject to minimizing the variance of mean life estimator. In these ALT plans, the highest acceptable test-stress was assumed to be specified in advance by the experimenter but there is no guidance for selecting it. This assumption is, however, inappropriate for many applications. Testing devices at too-high stress levels can invalidate the extrapolation model, or introduce failure mechanisms that are not anticipated under nomal operating conditions. In this paper, we propose new 4:2:1 compromise plans using Min-Max method to minimize this risk and present minimized test-stress levels(max, middle, min), and find sample allocation based on Min-Max 4:2:1 compromise plans. In result, we compare previous 4:2:1 compromise plans specified maximum test-stress with Min-Max 4:2:1 compromise plans minimized maximum test-stress.

• International Journal of Computer Science & Network Security
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• 제23권6호
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• pp.169-175
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• 2023

Ethical hackers are using different tools and techniques to encounter malicious cyber-attacks generated by bad hackers. During the software development process, development teams typically bypass or ignore the security parameters of the software. Whereas, with the advent of online web-based software, security is an essential part of the software development process for implementing secure software. Security features cannot be added as additional at the end of the software deployment process, but they need to be paid attention throughout the SDLC. In that view, this paper presents a new, Ethical Hacking - Software Development Life Cycle (EH-SDLC) introducing ethical hacking processes and phases to be followed during the SDLC. Adopting these techniques in SDLC ensures that consumers find the end-product safe, secure and stable. Having a team of penetration testers as part of the SDLC process will help you avoid incurring unnecessary costs that come up after the data breach. This research work aims to discuss different operating systems and tools in order to facilitate the secure execution of the penetration tests during SDLC. Thus, it helps to improve the confidentiality, integrity, and availability of the software products.

• 과학기술학연구
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• 제13권1호
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• pp.77-109
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• 2013

현재 의료체계의 주된 변화로 근거중심의학(Evidence-based Medicine: EBM)의 전지구적확산을 꼽을 수 있다. 최근 STS 연구들은 EBM이 실제 의학 실행 속에서 어떻게 사용되고 작동하는지에 대한 검토를 수행했는데, 이 글은 이러한 맥락 속에서 전립선암 특이항원(Prostate-specific Antigen: PSA) 의 조기진단 검사 도구 사용 여부를 둘러싸고 미국에서 벌어진 논쟁을 추적한다. 본 연구는 EBM이 PSA 검사 조기진단의 지지자와 반대자 양측에서 논쟁의 자원으로 이용되었으며, 그 과정에서 '확고한 과학적 기준'을 제시할 것으로 기대되던 EBM의 과학적 증거 위계가 행위자들의 의도에 따라 사실상'유연하게' 해석되고 동원되었음을 보일 것이다. 나아가, 이 글은 현재 EBM이 PSA 검사 반대자를 지지하는 것처럼 보이는 일은 삶의 질이라는 가치가 EBM의 체계 내에 주요한 변수로 부상하는 역사적 맥락에 의해 만들어진 결과임을 드러낼 것이다. 본 사례 연구는 EBM 시대에 의료기술에 관한 논쟁을 검토하는 연구자들이 EBM이라는 대상을 주어진 것으로 간주하기 보다는 논쟁 속에서 맥락화하여 논쟁과 함께 분석해야 함을 시사한다.

• 대한가정학회지
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• 제41권11호
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• pp.135-150
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• 2003

This research was to verity the effects of ICT teaching method in high school home economics. The research questions for this study were as follows: 1. Is the ICT teaching method effective in increasing students' interest in home economics and consciousness on traditional culture in teaming the unit of ‘Korean traditional culture of home life’？ 2. Is the ICT teaching method effective in improving students' achievement test and performance assessment in teaming the unit of ‘Korean traditional culture of home life’？ This study is carried out with following procedure: developing the homepage and lesson plans for ICT teaching, constructing questionnaire, and testing its reliability, pre-testing, treatment for 8 weeks, and post-testing. Two groups were arranged for 8 weeks experiment from May 7,2001 through June 30,2001. Sixteen hours of ICT teaching and 8 hours of traditional lecture for experiment group whereas 8 hours of ICT teaching and 16 hours of traditional lecture for comparison group were input. SAS program was used for statistical analysis, and independent sample t-test and matched pairs t-test were peformed for answering research questions. The results of this study were as following: 1. Sixteen hours of ICT teaching and 8 hours of traditional lecture for experiment group was effective in increasing consciousness on traditional culture and performance assessment. 2. Eight hours of ICT teaching and 16 hours of traditional lecture for comparison group was not effective in learning home economics. This means that at least 2 hours of ICT teaching is demanding for effective learning. This study concluded that ICT teaching will be effectively applied in high school home economic with well developed ICT teaching materials. And home economics educators should continuously put effort in developing curricular, teaching materials, and teaching methods to raise students' interest in home economics.

• Journal of the Korean Wood Science and Technology
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• 제41권5호
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• pp.385-391
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• 2013

X-ray computed tomography is a very powerful nondestructive technique in safety inspection of historic timber building. But, in field, various testing condition makes it difficult to carry out X-ray CT testing. Limited size in X-ray digital detector is one of the problems. In this study, a pitch pine disk with two holes was used to know how imperfection in X-ray projection affects CT image resolution. Using various number of projections, CT image was reconstructed by filtered back projection method, and then it was investigated how many projection is required to identify the holes in different location. Two artificial holes could be differently detected according to their location in cross section of specimen. One hole in center part of specimen was identified using more than 9 radiographs, but the other one which located in outer part of cross section could not be detected until more than 36 projections were used. Even though there is data missing in outer part of cross section due to limited size of detector, the center part of CT image could be reconstructed well and the resolution of outer part became higher with increase of the number of projections. For field application, the number of projections for CT image reconstruction needs to be decided with consideration of another nondestructive testing and the location of interest.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.997-1002
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• 2007

A guideway vehicle is used in automobile, semiconductor and LCD manufacturing industries to transport products efficiently. Since the operating speed of the guideway vehicle should be increased for maximum productivity, the weight of the vehicle has to be reduced. This may cause parts in the system to fail before the life of the system. Therefore estimation of the fatigue life of the parts becomes an important problem. In this study, the fatigue life of the driving wheel in the guideway vehicle is estimated using a S-N curve. To obtain the fatigue life of a part, the S-N curve, load time history applied on a driving wheel and material property are required. The S-N curve of the driving wheel is obtained using the fatigue experiment on wheels. Load time history of the wheel is obtained from multibody dynamics analysis. To obtain the material properties of the driving wheel, which is composed of aluminum with urethane coating, a compression hardware testing has been done with the static analysis of the FE model. The fatigue life prediction using computational analysis model guarantees the safety of the vehicle at the design stage of the product.

• 한국소음진동공학회논문집
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• 제25권3호
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• pp.176-183
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• 2015

This research proposes a method to estimate the fatigue life of SSD(solid-state drive) due to the effect of dummy solder ball under forced vibration. A finite element model of the SSD was developed to simulate the forced vibration and a modal testing was performed to verify the developed finite element model. Fatigue life of the SSD under vibration was experimentally determined according to JEDEC standard in which the SSD was excited by a sinusoidal sweep vibration within the narrow frequency band around the first natural frequency until the SSD fails. Basquin's equation was introduced to estimate the fatigue life of the SSD due to the effect of dummy solder balls. It shows that the dummy solder balls are effective elements of the SSD to increase the fatigue life of an SSD by increasing 700 times of the fatigue life of the given SSD.

• 한국신뢰성학회지:신뢰성응용연구
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• 제18권3호
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• pp.260-270
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• 2018

Purpose: The purpose of this study is to evaluate the life of the capsule, which is a core part of the heat storage cooling system. This paper will develop a life test mode that can reproduce environment conditions through the analysis of capsule shrinkage and expansion characteristics. Methods: In order to determine the life test mode of the capsule, this paper analyzed the case of field failures and analyzed the deformation characteristics according to the pressure fluctuation of the capsule. The method to find out whether the field failure and deformation analysis results are consistent is the testing with the construction of the repetition pressure test equipment and the thermal cycle test to reproduce the freezing and thawing characteristics. Results: In this study, failure mode analysis and analysis of freezing and thawing characteristics regarding to the capsule positions were completed. Based on this test & analysis results, this paper have been able to determine the main parameters for determining the life test mode, the freezing and thawing time. Conclusion: Determining the lifetime mode of the capsule can be used to improve the life and performance of the thermal storage system.

• 한국신뢰성학회지:신뢰성응용연구
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• 제5권2호
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• pp.273-287
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• 2005

Accelerated life test models and procedure are developed to assess the reliability of Refrigerator door switch. The main function of door switch is to operate bulb lamp and fan motor in the refrigerating room. The accelerated life test method and test equipments are developed using the relationship between stresses and life characteristics of the products. Using the developed accelerated life test method, the parameters of the ALT model and life time distribution are estimated and the reliability of the Door S/W at use condition if assessed. The proposed accelerated life test method and procedure may be extended and applied to testing similar kinds of products to reduce test time and costs of the tests remarkably.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권3호
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• pp.208-215
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• 2016

Purpose: ASRP for the domestic development guided missiles requires not only for the reliability evaluation of the products in storage but also for the life cycle management of the products including development prototypes and initial production items. Methods: For this purpose, it should be performed to build a performance database before and after the accelerated aging test with shelf life items including development prototypes and initial production items, based on which the lifetime prediction should also be carried out. In addition, HILS must be applied for the acceptance test with the initial and follow-up production items, and also for ASRP for the long-term storage products in order to secure systematic quality assurance. Results: The results for the life cycle reliability Improving of domestic development of guided missiles are DB building of prescription Item performance, active application of HILS, Management associated with guided missiles life cycle and to Secure technology data about the introduction of foreign guided missiles. Conclusion: Furthermore, it is demanded that DTaQ, the managing agency of ASRP, actively take part in the process to maintain reliability engagement consistency over the life cycle of guided missiles.