• Current Optics and Photonics
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• v.3 no.5
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• pp.429-437
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• 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 $-60{\sim}100^{\circ}C$.

• Journal of Korean Society for Quality Management
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• v.40 no.2
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• pp.145-155
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• 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
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• v.13 no.11
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• pp.1850126.1-1850126.10
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• 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.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1091-1098
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• 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.

• The Journal of Society for e-Business Studies
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• v.3 no.1
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• pp.43-67
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• 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
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• v.19 no.2
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• pp.602-611
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• 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.

• Journal of the military operations research society of Korea
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• v.18 no.2
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• pp.1-22
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• 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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.566-576
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• 2018

As the weapon systems of the Korean Army possess massive firepower and multiple functions, the improvement of their quality through reliability prediction is becoming increasingly important. Currently, the reliability prediction of the weapon systems of the Korean Army is a difficult process, because it is conducted by naively calculating the reliability of their constituent parts. Recently, as various studies using accumulated data are undertaken across various industries, the defense industry is also attempting to analyze the Dark Data which have been accumulated but not yet used. Therefore, it is necessary to apply Post-Logistics Support (PLS) data in order to improve the reliability of the weapon systems and, for this purpose, the Korean Army needs to conduct diverse studies. Especially, the PLS data in the defense industry is very useful for reliability prediction, because the data on the defects reported after the development of the weapon systems are accumulated in this phase. This study examines the existing reliability prediction method conducted using the component parts and proposes a new reliability prediction method using PLS data. This framework can ultimately contribute to improve the prediction accuracy and quality of the weapon systems.

• Journal of Applied Reliability
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• v.15 no.1
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• pp.1-5
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• 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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.90-98
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• 2018

An efficient R&D Methodology with minimized development period and cost needs to be developed due to advanced performance requirements of weapon systems. This will require the performance of logistics support analysis and design verification in the development stages of weapon systems through VR technology. VR technology has been applied to the Integrated Logistics Support (ILS) process as a part of collaborative system. In this study, we propose a development and application plan of ILS based on VR technology during the total life cycle of weapon systems. Moreover Digital Maintenance System (DMS) is introduced as a VR tool with key functions. finally, applications and improvement topics of DMS are suggested for use in ILS development.