• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.7
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• pp.635-640
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• 2015

In this paper, we report a non-explosive separation device for a small satellite which utilize a shape memory alloy actuator. Based on previous research, we try to increase the reliability of the proposed device by changing some components. It enables the proposed device to activate under high preload. Also, we confirm it generates low shock which is main advantage of non-explosive separation device. Finally, vibration test which mimics launching environment and thermal vacuum test which mimics space environment are carried out respectively. After each environment test, we confirm the proposed device is successfully activated. Conclusively, we develop a non-explosive separation device which can activate with low shock under high preload after shock and environment tests(vibration and thermal vacuum tests).

• Journal of Aerospace System Engineering
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• v.1 no.4
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• pp.22-27
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• 2007

The 150 gal Ion EFT(External Fuel Tank) used to enlarge the aircraft operation range was adopted an import equipment in T-50 FSD phase. But in Production phase the EFT was planed to develop for the stable ILS(Integrated Logistics Support) and technical ability improvement by using the composite materials. The design for configuration and fuel system is intended to maintain compatibility with aircraft systems and the development test is performed on component, assembly and aircraft. This study is conducted to provide the technology of design and test for the 150 gallon composite EFT in LRU level. The test results show that the composite EFT is satisfied with structural, functional and environment requirements which are described in specification.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.143-151
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• 2006

Currently, there are researches about environment-friendly road construction plans led by the Ministry of Construction and Transportation in progress. Therefore, in order to create the revegetation techniques of thin layer-soil combination media hydroseeding measures by actively using native herbs and native woody plants instead of using imported foreign grasses as a concept of sustainable environment-friendly land development, this thesis is going to identify problems that can appear when applying the thin- layer-soil-media hydroseeding measures by the suggested in the "Slope revegetation design and guidelines" proposed by the Ministry of Construction and Transportation, and to propose improvement plans for the problems.To this aim, a seeding mixture selection test was conducted by the goal of slope restoration, and a test group for artificial slope was created. As for a test for June sowing, it was intended to identify appropriate combination quantity by conducting a test that differentiates the combination quantity, and as for a test for September sowing, an artificial slope test was conducted by creating an artificial bank for earth and soil and applying 1~2cm and 3~4cm thickness after differentiating the seed combination volume and slope aspects.

• KIEAE Journal
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• v.12 no.3
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• pp.69-75
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• 2012

Developing reliable measures of the environment is important to increase our understanding of the environmental effects on walking among seniors. As a preliminary study for developing an instrument for measuring walkability of seniors' environment, the purpose of this study are to identify important assessment indicators associated with seniors' walking and to test their reliability using inter-rater and intra-rater reliability methods. A set of assessment indicators was identified through literature review, and field studies by trained raters were conducted in three senior centers located in Seongnam area in order to test reliability of the audit tool. The results indicated high percent agreement for most indicators and overall 91.6% and 86.1% of items assessed had good or medium inter-rater and intra-rater reliability, respectively. The reliable assessment indicators would provide reliable data for use in community-based audits of built environment in relation to walking among older adults. The findings showed that the indicators of aesthetics had lower reliability compare to safety, convenience, and access. Rater training with various images would improve rater agreement while reduce rater bias.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.4
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• pp.165-172
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• 2016

A Global Navigation Satellite System (GNSS), which is typically exemplified by the Global Positioning System (GPS), employs a open signal structure so it is vulnerable to spoofing electronic attack using a similar malicious signal with that used in the GPS. It is necessary to require a spoofing test evaluation environment to check the risk of spoofing attack and evaluate the performance of a newly developed anti-spoofing technique against spoofing attacks. The present paper proposed a simulation method of spoofing environment based on simulator that can be implementable in a test room and analyzed the spoofing simulation performance using commercial GPS receivers. The implemented spoofing simulation system ran synchronized two GPS simulator modules in a single scenario to generate both of spoofing and GPS signals simultaneously. Because the signals are generated in radio frequency, a commercial GPS receiver can be tested using this system. Experimental test shows the availability of this system, and anti-spoofing performance of a commercial GPS receiver has been analyzed.

• Biomedical Science Letters
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• v.11 no.4
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• pp.447-453
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• 2005

A total of 108 strains of MRSA (Methicillin-resistant Staphylococcus aureus) clinical isolates was collected from $121^{st}$ general hospital (U.S. military hospital), Korean healthcare facility from January to March in 2005 and Wonju Christian hospital in 1999. Antimicrobial susceptibility test by Vitek System and MIC test using oxacillin and cephalothin stripes by E-test were executed. PCR based detection of mecA gene was performed on the all of MRSA clinical isolates, too. MRSA clinical isolates were characterized with antimicrobial resistance patterns, PCR based detection of mecA gene and validation of the multiplex PCR strategy of SCCmec among clinical isolates.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.391-396
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• 2005

Salt water spray test and salt water immersion test were experimentally conducted in order to investigate the durability of fiber reinforced composites under salt water environment. The specimens were made of glass fabric reinforcement and phenolic resin. Mechanical test was performed to obtain mechanical properties such as tensile properties, flexural properties, and shear properties by varying with exposure times. Also dynamic mechanical test and FTIR were conducted to investigate a change in chemical structure as well as thermal analysis properties such as storage shear modulus, loss shear moduls, and tan ${\delta}$. According to the results, salt water environment has effected on mechanical properties and thermal analysis properties and especially the durability of glass fabric/phenolic composites were severely affected on salt water immersion environment rather than salt water spray environment.

• Convergence Security Journal
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• v.22 no.1
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• pp.3-9
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• 2022

The role of the integrated development environment is very important in software development of a development project. After many developers develop different modules, software product is completed through compile, debugging, integration, testing, and distribution. However, bugs and various issues in the development process cause problems such as quality deterioration of software product and dissatisfaction with requirements. So the need for automated testing to avoid these problems and improve quality has increased. In this study, we propose test automation modules of four perspectives to improve quality throughout the test automation in an integrated development environment. Each automation module operates through the tool chain of an integrated build framework implemented on the devops.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.2
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• pp.29-36
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• 2004

As Lately movie industry and related market becomes larger and people have had more spare time, people's interest in multiplex grows higher, This paper studies relationships between physical service environment and customer's satisfaction in multiplex. The number of subjects in this study is 346 persons stayed at four multiplexes, among which we obtained valid responses from 326 persons through questionnaire investigation. We held hypotheses for the relationships, and for the testing, used methods are Spearman's correlation, Mann-Whitney test, etc, and for statistical analysis, SPSS 10.1 software was used. Thus, we found statistically significant results, that is, the relation between physical service environment and customer's satisfaction is positive: the higher evaluation about physical service environment is, the more customer's universal satisfaction is. Information about the significant relation's intensity of many indicators in physical service environment, which is given in this paper, can be used for attaining higher customer satisfaction and spreading more effective management activities in multiplex.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.6
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• pp.591-601
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• 2020

After North Korea's sixth nuclear test, the operational environment on the Korean Peninsula has fundamentally changed, and the South Korean military faces various security challenges, including a reduction in military service resources and shorter military service periods. In particular, the South Korean military is seeking a new paradigm in military construction amid changes in the defense acquisition environment linked to the push for defense reform 2.0 and the utilization of the fourth industrial revolution. Therefore, this study considered strategies for improving the operational test and evaluation of weapons systems suitable for changes in the defense acquisition environment to effectively prepare for existing military threats and future warfare patterns. For this purpose, external environment analysis and internal capabilities were diagnosed using PEST Analysis and SPRO Analysis, and improvement strategies were derived through SWOT analysis.