• 국제강구조저널
• /
• 제18권4호
• /
• pp.1284-1296
• /
• 2018

Carbon fiber reinforced polymer (CFRP), plates bonding repair method is one of the simple repair methods for cracked steel structures. In this study, the influence of width of CFRP plates on bending fatigue life of out-of-plane gusset joint strengthened with CFRP plates was investigated from the experimental and numerical point of view. In the bending fatigue test of cracked out-of-plane gusset joint strengthened with CFRP plates, the effect of width of CFRP plates on crack growth life was clarified experimentally. Namely, it was revealed that the crack growth life becomes larger with increasing the width of CFRP plates. In the numerical approach, the stress intensity factor (SIF) at the surface point of a semi-elliptical surface crack was estimated based on the linear fracture mechanics. Furthermore, the extended fatigue life of cracked out-of-plane gusset joint strengthened with CFRP plates was evaluated by using the estimated SIF at the surface point and the empirical formula of the aspect ratio of semi-elliptical crack. As the results of numerical analysis, the estimated fatigue life of the specimen strengthened with CFRP plates showed the good agreement with the test results.

• 품질경영학회지
• /
• 제47권3호
• /
• pp.437-451
• /
• 2019

Purpose: The purpose of this study is to improve the quality of the PGM system by improving the structure and production process of slip-ring rotary joint for radar. Methods: The improvement measures for each cause are established through failure analysis of broken items. Specifically, changing in the housing to improve the heating system. Changing the transportation method to prevent damage to equipment during transport. Changing work process of the attenuator ring to prevent damage. etc. Results: The results of this study are as follows; improving the heating system reduces heat generated by the attenuator by about 7 degrees and obtain additional temperature margins. Reduction of defect rate because of adding X-band rotary joint run-out measurement test, ESS of slip-ring rotary joint and Transportation improvement(reinforced flight boxes, tube protection, etc). Getting stable VSWR values by improving work process of attenuator overheating due to a bad bonding process. Conclusion: Through this study, improvements were made to slip-ring rotary joint that failed repeatedly for various reasons. As a result of the application of the improvements, the same fault does not occur until now, so we can see that the quality of PGM has improved.

• 한국정보통신학회논문지
• /
• 제22권10호
• /
• pp.1355-1360
• /
• 2018

헬스케어 산업은 빅데이타, ICT(Information and Communications Technologies), IT 기기 등의 결합으로 서비스 범위가 확대되고 관리가 생애주기 전반에 걸쳐 이뤄질 것으로 예상된다. 본 논문은 헬스케어의 한 분야로 엄지손가락에 대한 손허리손가락관절굽힘과 손가락뼈사이관절굽힘에 대하여 알아보도록 한다. 손허리손가락관절굽힘은 엄지 손허리손가락 관절을 구부리는 것을 말하고 손가락뼈사이관절굽힘은 엄지손가락뼈사이 관절을 구부리는 것을 말한다. 관절을 구부릴 때 일정한 정해진 각도에 미달하거나 통증을 느끼면 이상이 발생한 것이다. 또한 엄지손가락관절의 이상에 대한 예방법과 치료법도 제시하였다. 50대 50명을 대상으로 엄지손가락 관절에서 손허리손가락관절굽힘과 손가락뼈사이관절굽힘에 대한 실험을 수행하였다. 본 시스템은 몸의 일부에 한정되어 있지만, 이를 부분적으로 확대해 나간다면 빅데이타 헬스케어시스템 구축의 기반이 될 것이다.

• Management Science and Financial Engineering
• /
• 제4권2호
• /
• pp.15-42
• /
• 1998

A joint problem of order delivery, setup reduction, and cost-sharing in a two-echelon inventory system in which a vendor supplies multiple products to a group of buyers is studied here. The basic premise is that buyers have independently implemented setup reduction programs to acquire benefits from small order sizes. Doing so, however, causes the buyers' individually optimal order cycles to be differ from that of the vendor. In conjunction with this, two models are considered. In the first model, a multi-buyers single product situation is considered in which the vendor implements a joint supply cycle policy. However, buyers, as the dominant party, insist after implementing the individually optimal setup reduction that the vendor accept their individually optimal order schedules. In the second model. a multi-products, single buyer situation is considered in which the buyer implements a joint order policy. Here, the vendor, as the dominant party, refuses to cooperate fully with the buyer's individually reduced joint order schedule, and designs his own individually optimal setup reduction mix for each product under a given budget constraint. This led to a study of an integrated Setup Reduction/Break-even Pricing Policy for each situation to eliminate mismatches in individually optimal cycle times.

• 품질경영학회지
• /
• 제43권3호
• /
• pp.289-298
• /
• 2015

Purpose: This study examined the problem of crack formation in the fire control system(FCS) of the K11 objective individual combat weapon(OCIW), using design of experiment analysis. Three hypothesis were considered. The first hypothesis is that bolted joint has an effect on impulse caused by firing the weapon and the second hypothesis is that a short time interval of shooting has an effect on impulse and lastly, the third hypothesis is that a positive correlation has between the bolted joint of the FCS and the impulse. Methods: The relationship between the bolted joint and the impulse cause by firing the weapon were examined experimentally. The first and second hypothesis was tested using correlation analysis and the t-test. Results: Using ANOVA, the first null hypothesis was rejected and the alternative hypothesis was accepted. ANONA confirmed the second null hypothesis. Correlation analysis dismissed the last null hypothesis. A positive correlation between the bolted joint and the impulse caused by shooting the weapon was verified. Conclusion: The bolted joint of the K11 FCS and the barrel of the K11 affect the impulse caused by firing the weapon. A positive correlation was established between the bolted joint of the FCS and the impulse on firing the K11 OICW.

• International Journal of Computer Science & Network Security
• /
• 제21권11호
• /
• pp.271-275
• /
• 2021

The article assesses the role of the human factor in management, analyzes the personnel policy, as well as the style and methods of management at the enterprise. The purpose of the article is to study the place and role of personnel management in the general management system of an organization. Particular tasks of the research have been solved: the place and role of personnel management in the system of general management theory have been determined; determined the place of personnel management in the system of modern sciences.

• International Journal of Air-Conditioning and Refrigeration
• /
• 제12권2호
• /
• pp.97-107
• /
• 2004

Wall/floor intersection is important parts of a building envelope system. These intersections can be sources of thermal bridging effects and/or moisture condensation problems. This paper provides a detailed analysis of the thermal performance of wall/floor intersection. In particular, two-dimensional steady-state and transient solutions of the heat conduction within the wall/floor joint are presented. Various insulation configurations are considered to determine the magnitude of heat transfer increase due to wall/floor joint construction.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2001년도 춘계학술대회 논문집
• /
• pp.24-29
• /
• 2001

Despite of the introduction some sorts of the contract and the bid method like CM(Construction management) that will be efficient to manage the construction project. Korean agencies limit to control project management to do large public constructions. In the case of Taiwan, THSRC is apply J/V system in the public construction project, they are accomplishing that expend optimal the cost and save the construction time. To success J/V it has two factors, one is risk management and another is sharing information of construction project. Therefore, we will study to introduce J/V system to our construction project.

• 항공우주시스템공학회지
• /
• 제17권6호
• /
• pp.108-117
• /
• 2023

지금까지 해외 수출용 KT-1 군용 고정익 항공기에 통합된 임무 소프트웨어는 해외업체와 국제 공동개발을 통하여 개발이 되었으며, 감항인증을 위해 DO-178B를 기반으로 하는 해외업체의 개발 환경과 절차를 준수함으로써 소프트웨어의 신뢰성을 인정받을 수 있었다. 하지만, 최근에는 해외 수출 시 DO-178C 인증을 요구하고 있으며, 국내 소요군에 납품 시 방사청 무기체계 소프트웨어 개발 및 관리 매뉴얼 준수를 위해 신뢰성 시험을 필수적으로 요구하고 있다. 본 논문은 기 개발된 KT-1 수출형 항공기 체계통합 사업의 국제 공동개발에 있어 국내 감항인증을 받기 위한 문제점을 기술하고 DO-178C와 무기체계 소프트웨어 개발 및 관리 매뉴얼을 모두 준수하기 위한 해결방안을 찾아서 최적의 소프트웨어 신뢰성 시험 방안을 제시한다.

• 대한환경공학회지
• /
• 제39권11호
• /
• pp.650-654
• /
• 2017

화학물질의 취급량 증가에 따라 화학물질 관리 제도를 전면적으로 개편하는 움직임이 국제적으로 일어나고 있다. 한국 역시 화학물질 관리 제도를 전면 개편하여 화학물질관리법과 화학물질 등록 및 평가에 관한 법률이 제정되었다. 하지만 화학물질관리법의 경우, 법 시행 4년째를 앞두고 여러 개선사항이 드러나고 있다. 따라서 본고에서는 화학물질관리법의 제언한 개선사항에 대한 보완점을 연구하고 그에 맞는 발전방향을 제시하여 화학물질관리법이 오랫동안 안전한 화학물질 관리제도로서 대내외에 널리 도입되고 연구되었으면 하는 바람이다.