• Current Optics and Photonics
• /
• 제3권5호
• /
• pp.429-437
• /
• 2019

Temperature adaptability is an important metric for evaluating the performance of an optical system. The temperature characteristics of the optical system are closely related to the material and shape of its lens. In this paper, we establish a mathematical model relating the temperature characteristics to the shape and material of the lens. Then a novel assembly structure that can solve the lens constraint and positioning problem is proposed. From those basics, the correctness of the theoretical model and the effectiveness of the assembly structure are verified through simulated analysis of the imaging quality of the optical system, whose operating temperature range is $-60{\sim}100^{\circ}C$.

• 품질경영학회지
• /
• 제40권2호
• /
• pp.145-155
• /
• 2012

The purpose of this study is to suggest the direction of improving service quality in the defense logistics support. For this, this study compares and analyzes the perceived service quality between customer(using unit) and defense logistics support unit by using SERVPERF model. Supply, military meals, and maintenance are carrying out the mission as core function of defense logistics support and also encounter with customer. In this empirical analysis, the service quality is composed of four factors, and there are significant difference in perception level of service quality between them. Also, the relationship between factors of service quality and revisit intention shows significant difference statistically, and the customer orientation and responsiveness are key affecting factors on revisit intention.

• Nano
• /
• 제13권11호
• /
• pp.1850126.1-1850126.10
• /
• 2018

Flexible strain sensors, as the core member of the family of smart electronic devices, along with reasonable sensing range and sensitivity plus low cost, have rose a huge consumer market and also immense interests in fundamental studies and technological applications, especially in the field of biomimetic robots movement detection and human health condition monitoring. In this paper, we propose a new flexible strain sensor based on thick CVD graphene film and its low-cost fabrication strategy by using the commercial adhesive tape as flexible substrate. The tensile tests in a strain range of ~30% were implemented, and a gage factor of 30 was achieved under high strain condition. The optical microscopic observation with different strains showed the evolution of cracks in graphene film. Together with commonly used platelet overlap theory and percolation network theory for sensor resistance modeling, we established an overlap destructive resistance model to analyze the sensing mechanism of our devices, which fitted the experimental data very well. The finding of difference of fitting parameters in small and large strain ranges revealed the multiple stage feature of graphene crack evolution. The resistance fallback phenomenon due to the viscoelasticity of flexible substrate was analyzed. Our flexible strain sensor with low cost and simple fabrication process exhibits great potential for commercial applications.

• 한국군사과학기술학회지
• /
• 제13권6호
• /
• pp.1091-1098
• /
• 2010

Victory and defeat of the war depends on follow-on logistics support. The spending time of follow-on logistics support at combat area is greatly influenced by the degree of combat intensity. The main purpose of this study is to compose a optimal supply route for operational sustainability of combat unit at combat area using transport vehicles. This study suggests a composition of optimal supply route for follow-on logistics support which considers the degree of combat intensity. A mathematical programming model and a genetic algorithm suggest to minimize the total spending time of follow-on logistics support. The suggested mathematical programming model is verified by using CPLEX 11.1. This study computes supply route, total spending time, total travel distance, and the number of transport vehicle.

• 한국전자거래학회지
• /
• 제3권1호
• /
• pp.43-67
• /
• 1998

Logistics is by no means a new subject area. The concept of logistics goes way become more complex as technology advances, and logistics requirements have increased accordingly. In 1964, when ILS philosophy formally came into being, ILS was defined in general terms and did not describe what actions an ILS program should accomplish. ILS philosophy have been developed from 1964 through 1980. In 1982, United States Department of Defense formulated a new concept, CALS. CALS is the strategy that the US defense development to management the transition to integration and automated interchange in defense system engineering, manufacturing, and logistic support. Its goal is to use the inherent features of digitized data to revolutionize the function of data -gathering, data storage and data - transfer techologies associared with the development of defense systems. The Result will be systems that are cheaper, more reliable, and easier to maintain. To define CALS's character, the purpose of this papers compare two concepts - CALS and ILS. The elements of CALS consist of standads and EDI. The elements of ILS include LCC(Life Cycle Cost), LSA(Logistics Support Analysis), LSAR(Logistics Support Analysis Rcord), Aquisition Cycle.

• Journal of Power Electronics
• /
• 제19권2호
• /
• pp.602-611
• /
• 2019

The major drawbacks of magnetic resonant coupled wireless power transfer (WPT) to the embedded sensors on spindles are transmission instability and low efficiency of the transmission. This paper proposes a novel double-loop coil design for wirelessly charging embedded sensors. Theoretical and finite-element analyses show that the proposed coil has good transmission performance. In addition, the power transmission capability of the double-loop coil can be improved by reducing the radius difference and width difference of the transmitter and receiver. It has been demonstrated by analysis and practical experiments that a magnetic resonant coupled WPT system using the double-loop coil can provide a stable and efficient power transmission to embedded sensors.

• 한국국방경영분석학회지
• /
• 제18권2호
• /
• pp.1-22
• /
• 1992

Computer-aided logistics support system is recognized an essential system to reduce supply and maintenance cost, and to improve readiness of weapon system or operationable composite machines. According to these trends, this paper focuses on the design scheme and the computerization strategy of information management system for Integrated Logistics Support (ILS) work. Suggested system. LAMIS(Logistics support Analysis Management Information System) is a total system that composed of Logistics Support Analysis Management information system (LSAM), Configuration Management Information System (CMIS), Maintenance Management Information System (MMIS), Project Management System (PMS) and Information Retrival System(IRS) etc. Also, LAMIS is a computerized tool that improves current supply and maintenance support program, that attempts to reliable requirment analysis of logistics support elements, and that supports to use the existing technical specification of similar one when weapon system acquisition project is started newly. When LAMIS implication is completed, it can be applied to logistics support of defense or commercial site. Straightway, LAMIS will be enhanced with computer - aided design system, engineering drawing system, interactive electronic technical manual system, electronic data interchange system, and three dimensional simulation system to weapon system configuration. When that is done, LAMIS is CALS system.

• 한국산학기술학회논문지
• /
• 제19권1호
• /
• pp.566-576
• /
• 2018

우리 군의 무기체계는 강력한 화력과 다양한 기능을 보유하고 있으며, 이에 따라 무기체계 신뢰도 예측을 통한 품질 향상의 중요성 역시 점점 커지고 있다. 현재 우리 군의 무기체계 신뢰도 예측은 무기체계를 구성하는 부품들의 신뢰도들의 단순 합계를 통해 이루어지기 때문에 정확한 신뢰도 산출이 어렵다. 따라서 군은 신뢰도 향상을 위해 다양한 연구를 수행할 필요가 있다. 최근 다양한 산업에서 축적된 데이터를 활용한 많은 연구가 시도됨에 따라, 방위산업에서도 축적되고 있지만 활용되지 않은 다크(Dark) 데이터에 관한 분석을 시도하고 있다. 특히, 방위산업의 후속군수지원 단계는 무기체계의 신뢰도 향상을 위한 후속군수지원(PLS) 데이터를 활용할 필요가 있다. 본 연구는 부품단위의 기존 신뢰도 예측 방법에 대한 현황과 문제점을 검토하고, 후속군수지원의 결함 데이터의 적용방안을 제시한다. 이로 인해 무기체계 개발 시 신뢰도 예측의 정확성과 품질 향상에 도움이 될 것으로 기대한다.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제15권1호
• /
• pp.1-5
• /
• 2015

This note suggests three approaches to improve reliability in developing weapon systems. The high complexity of the weapon systems make it hard to analyze and predict of those reliability. Current situations of the reliability have been reviewed in terms of logistics support analysis (LSA), warranty policy, maintenance and development. Three suggestions are notified to improve the reliability considering the complexity of the weapon systems.

• 한국산학기술학회논문지
• /
• 제19권12호
• /
• pp.90-98
• /
• 2018

최근 무기 체계에 대한 성능 요구 사양이 강화됨에 따라 연구 개발 초기 단계에서부터 개발 기간 단축 및 비용 최소화와 함께 효율적인 연구 방안 모색이 요구되고 있다. 이의 일환으로 무기 체계 개발 단계에서 가상현실 기술을 활용하여 군수지원 분석과 설계 검증을 수행할 수 있다. 또한 실질적 협업 체계 구축의 일환으로 종합 군수지원(ILS, Integrated Logistics Support) 개발 분야에서는 군수 지원성 향상을 목적으로 한 가상현실 기술의 적용이 대두되고 있다. 이에 본 연구에서는 무기 체계 전 수명주기 동안 가상현실 기술을 적용한 ILS 개발 및 적용 방안을 제안하고자 한다. 또한 현재 개발 중인 무기 체계에서 이를 수행하기 위해 개발한 가상현실 도구인 디지털 정비절차 검증장치(DMS, Digital Maintenance System)의 주요 기능 및 ILS 개발 단계별 적용 방안을 소개하고, DMS의 효율적인 ILS 적용을 위한 향후 발전 과제에 대해서도 제시하고자 한다.