• The Journal of the Acoustical Society of Korea
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• v.29 no.4
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• pp.223-228
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• 2010

High-frequency bottom loss measurements for grazing angle of $82^{\circ}$ in frequency range 17-40 kHz were made in Jinhae bay in the southern part of Korea. Observations of bottom loss showed the strong variation as a function of frequency, which were compared to the predicted values using two-layered sediment reflection model. The geoacoustic parameters including sound speed, density and attenuation coefficient for the second sediment layer were predicted from the empirical relations with the mean grain size obtained from sediment core analysis. The geoacoustic parameters for the surficial sediment layer were inverted using Monte Carlo inversion algorithm. A sensitivity study for the geoacoustic parameters showed that the thickness of surficial sediment layer was most sensitive to the variation of the bottom loss.

• Journal of Science Education
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• v.39 no.3
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• pp.343-357
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• 2015

The present study aims to analyze the extent of the use of STS contents in the areas of 'Evolution of Life' and 'Health of Humanity and Scientific Technology' in 'Science' textbooks and to determine whether they meet the goals of the curriculum revised in 2009. The analysis of the 7 types of textbooks according to the STS topics areas indicated big differences between textbooks as little as 16.67% and as much as 58.33%. Also, among the topics associated with STS, 'Space Development and National Defense' and 'Environmental Problems' were not included. In the STS activity areas, the areas of 'Structured Debate,' 'Interpretation of Data,' 'Research and Investigation' showed great frequency. On the other hand, the STS activity areas of 'Field Activities,' 'Problem-solving and Decision-making,' 'Role Playing,' 'Simulation,' 'Case Study,' and 'Research Design' showed small frequency. Analysis of the STS contents for each area indicated 67.57% for the contents relevant to 'the applicability of science' accounting for the largest part whereas 'Understanding of Occupations related to Science' accounted for 1.63%, showing a great difference in their frequency. Seven standards except 'the applicability of science' were included each contents beyond 10% or less than 10% proportion. The STS contents included in the life science area of the 7 types of convergence-style 'Science' textbooks for the high-school accounted for an average of 20.75%, from as little as 12.35% to as much as 26.90%, depending on the publishes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.648-654
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• 2018

Currently, the Defense Agency for Technology and Quality (DTaQ), which is responsible for the quality assurance of military supplies, divides munitions into four categories, in order to conduct its governmental quality assurance activities, including product examination, process review and system audit. However, these 4 categories may differ depending on the related organizations' (e.g. Defense Acquisition Program Administration, munitions manufacturing) military requirements. Therefore, in this study, appropriate classification criteria for munitions are suggested for the sake of the efficient procurement, production and quality assurance of military supplies. We investigated the item classification system of the Public Procurement Service, which is a similar organization to the DTaQ. We also compared the appropriate classification criteria with those of related organizations and identified the current status of munitions classification data according to the current standard. In addition, application samples are presented using the proposed quality assurance classification criteria. Finally, the classification criteria of military supplies proposed in this paper will contribute to improving the efficiency of government quality assurance activities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.417-422
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• 2017

One of the most frightening aspects of weapons of mass destruction (WMD) is their ability to cause death in very small quantities without being visible to the public. The military authorities are making considerable effort to ensure the survivability of the combatants in the event of NBC(Nuclear, Biological and Chemical) contamination. Therefore, in this study, modules were developed for the measurement of the positive pressure and for the detection of the chemicals used for the control of the various shut-off valves used in an NBC shelter. In addition, a high performance gas tight shut-off valve was developed that can overcome the disadvantages associated with manual manufacturing, such as the occurrence of defective products and high manufacturing cost. By applying the positive pressure measurement and chemical detection modules, this valve was able to be used to control the facility. The developed gas-tight shut-off valve maintained airtight characteristics at a pressure loss of 28[Pa] at the prescribed wind velocity and an internal pressure of 30[kPa]. It is expected to be possible to control the gas-tight shut-off valve through the remote measurement of the positive pressure, thereby ensuring the foreign independence of import substitution and defense related technology in the future. In addition, by installing these valves in all of the intake ports or exhaust ports connected to the outside of the NBC shelter, it is possible to prevent the damage resulting from the rapid inflow of the storm pressure caused by conventional weapons and nuclear explosions, thereby protecting the people and equipment in the shelter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.146-152
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• 2016

The purposes of this study were to investigate the effects of professional soldiers' family healthiness on the organizational effectiveness of the military and test for any differences in the structural modeling path caused by the mediating effects of empowerment depending on whether they lived with their families or not. Data were collected with a self-administered survey distributed to 480 professional soldiers after the approval of the Ministry of National Defense. The data collected were then analyzed using descriptive statistics, structural equation modeling, and multi-group analysis. The analysis results show that the family healthiness of all of the professional soldiers had direct or indirect effects on their organizational effectiveness via empowerment and that family healthiness was a variable with a very large explanatory power for organizational effectiveness. Both family healthiness and empowerment had effects on the organizational effectiveness of the solders that were living with their families and those who lived separately from their families. The levels of family healthiness, empowerment, and organizational effectiveness were all high among the professional soldiers that were living with their families and all low among those who were not. Increasing the family healthiness and empowerment was found to enhance the organizational effectiveness in all of the models, and a higher organizational effectiveness would be expected from professional soldiers living with their families. These findings led to a proposal that various plans should be prepared to help professional soldiers live with their families and provide them with family welfare support.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.4
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• pp.42-50
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• 2009

Ubiquitous computing technology is widely used in not only our everyday lives but also in education, medical care, military, environment and administration. RFID system, the basis of ubiquitous, is in the spotlight which can be an alternative solution of a bar code recognition system and magnetic system as they basically have practicality and security issues. An electronic authentication named smart-key system is recently concerned by an alternative solution of the security unit for an automobile. RFID system which has a general purpose is also in the limelight by an application technology. In this paper we designed vehicle smart key system with general-propose RFID system that is already in use. First, we designed control unit and RFID card reader for vehicle smart key system. Then we propose an algorithm and prove that the vehicle key system is controllable by showing the result of implementing and testing, after installing. Also security level is enlarged by proposing a authentication protocol between RFID reader and control unit.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.11
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• pp.1094-1103
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• 2012

Recently, software industry regarding national defense increases system development of distributed simulation system of M&S based to overcome limit of resource and expense. It is one of key technologies for offering of mutual validation among objects and reuse of objects which are discussed for developing these systems. RTI, implementation of HLA interface specification as software providing these technologies uses Federation Object Model for exchanging information with joined federates in the federation and each federate has a characteristic that is supposed to have identical FOM in the federation. This technology is a software which is to provide the core technology which was suggested by the United state's military M&S standard framework. Simulator, virtual simulation, and inter-connection between military weapons system S/W which executes on network which is M&S's core base technology, and it is a technology which also can be used for various inter-connection between S/W such as game and on-line phone. These days although RTI is used in military war game or tactical training unit field, there is none in Korea. Also, it is used in mobile-game, distribution game, net management, robot field, and other civilian field, but the number of examples are so small and informalized. Through this developing project, we developed the core technique and RTI software and provided performance of COTS level to improve communication algorithms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.546-551
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• 2020

Generally, surface vessels have many compartments for operation and living quarters, and each compartment is an important space for the ship's survivability. During ship construction, a compartment leak test is necessary and is carried out on each vessel. However, the current test method is in doubt when looking at the actual test results. The reason is that only one pressure gauge is used for the measurement to check the air, so an uncomprehended phenomenon is detected during group compartment leak tests. From this point of view, an improved test device and method are needed. In this study, a multi-channel data acquisition device with multiple pressure sensors is proposed to detect each compartment's pressure variation or pressure drop. This test is a more confidential compartment leak test than the current method, and the test device can show real-time pressure detection values of each of the pressure sensors, which are installed in each compartment, including unmanned space.

• Journal of the Korean Chemical Society
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• v.45 no.3
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• pp.256-263
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• 2001

The STS contents, emphasized in the 6th curriculum, in the chemistry parts of general science textbooks were analyzed. The STS contents of textbooks showed average of 24.4%. The chapter in "modern science and technology" were included 45.5% in STS contents, 38.7% in "environment", 29.1% in energy, and 14.0% in "materials". When the STS contents were analyzed by STS topics of Piel, the results are as follows; 38.3% on environmental quality and utilization of natural source, 29.6% on effect of technological developments, 7.9% on energy, and 0.6% on human engineering. However, there were no topics on population, space research and national defense. When the STS contents were analyzed by student activities of SATIS, most of the activities were research and case study. There were few field activities of role play, problem solving and decision making, and research design.

• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.237-266
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• 2009

In 1631 A.D. Jeong Duwon, an ambassador of the Joseon dynasty was sent to the Ming dynasty. There he met $Jo\tilde{a}o$ Rodrigues, a Jesuit missionary, in Dengzhou of Shandong peninsula. The missionary gave the ambassador a number of results of latest European innovations. A detailed description on this event was written in 'Jeong's official report regarding a message from an European country'(西洋國奇別狀啓), which is an important literature work to understand the event. Since the document was written in classical Chinese, we make a comprehensive translation to Korean with detailed notes. According to the report, the items that Rodrigues presented include four books written in Chinese that describe European discoveries about the world, a report on the tribute of new cannons manufactured by Portuguese in Macao, a telescope, a flintlock, a Foliot-type mechanical clock, a world atlas drawn by Matteo Ricci, an astronomical planisphere, and a sun-dial. We discuss the meaning of each item in the Korean history of science and technology. In particular, Jeong's introduction is an important event in the history of Korean astronomy, because the telescope he brought was the first one to be introduced in Korean history. Even though king Injo and his associates of the Joseon dynasty were well aware of the value as military armaments of new technologies such as telescopes, cannons, and flintlocks, they were not able to quickly adopt such technologies to defend against the military threat of Jurchen. We revisit the reason in view of the general history of science and technology of east-Asian countries in the 17th century.