• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.111-118
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• 2009

This study is to analyze the performance of SWH(Solar Water Heating) and GSHP(Ground Source Heat Pump) systems by evaluating their energy efficiency and LCC(Life Cycle Cost) as being applied to the OO hall as a selected building in the Army. The OO hall, used as bathrooms, dining rooms, accommodations and offices, has reinforced concrete structure system with three floors above the ground and one underground, and its total floor area is approximately 2,917$m^2$. Two energy simulations are conducted to predict the yearly cooling and heating energy of the selected building: One is for analysis of an air-conditioning energy consumption using the e-Quest program, and another is for two new-renewable energy facilities as a water heating source using the RETScreen. The installed capacity of two new-renewable energy facilities is determined according to the 5% level of total standard construction cost. As a briefly result, SWH system is more energy-effective than GSHP system. Considering the break-even point, it is expected that SWH can take only 3 years 11 months to pay for itself in savings while the investment of GSHP can be recovered in more than 16 years 6 months.

• Journal of the Korea Concrete Institute
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• v.29 no.2
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• pp.169-177
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• 2017

Rather than causing damage from heat, blast, and radiation of a regular nuclear weapon, recently, it is predicted that North Korea has been inventing high altitude electromagnetic pulse (HEMP) missile in order to incapacitate electronic equipment. HEMP shielding facility is used for military purpose today. Despite the electromagnetic shielding effects from high quality compression plates, problems may include such as the possibility of electromagnetic influx resulting in the welding of the compression plates, and difficulties and high cost of construction. Therefore, in this study, a high electrical conducting material was added to the concrete experimental subject to ensure the shielding effect through electromagnetic waves to for the concrete structure, instead of building a shielding facility separately for the structure. Also, among the experimental subjects, 100 ${\mu}m$ of Iron-Aluminum alloy metal spraying coat was applied to two types with the highest shielding effect, and to two types with the lowest shielding effect. The result of the experiment indicates that experimental subjects added with a high electrical conductivity material did not meet the minimum shielding criteria of MIL-STD-118-125-1 standard, but all the experimental material applied to the metal spraying coating satisfied the minimum shielding criteria. In conclusion, it is considered that 100 µm of Iron-Aluminum alloy metal spraying coat contains high efficiency in the HEMP shielding.

• Journal of architectural history
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• v.17 no.2
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• pp.47-66
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• 2008

This research was to analyze the border signal-fire which is the main facility of military protective duty for safety of sea side in chosun dynasty. The results of this research were described separately as follows. 1. Five types of site plan of signal-fire were observed, which is circle, half-circle, oval, round-rectangular. The majorities were circle type in eastern area. 2. Plan configuration of signal-fire stand which is separated with circle, rectangular type roughly was constructed with circle type generally. The height of signal-fire stand was about $2{\sim}3m$. The diameter of signal-fire stand was $8{\sim}10m$. Building base that protect ground moisture and infilteration of rainfall was found in 9 border singal-fire, the height of it was about $0.3m{\sim}2.5m$. 3. Trench was mainly circle type and average width was $3{\sim}4m$. However the depth was almost observed as 1m, originally, it was estimated it has more depth. 4. The height of protective wall remained until present was about 1m, the depth was about average 2.5m. 5. The storage of border signal-fire has rectangular dimension, several types of $1.8{\times}1.2m{\sim}5.7{\times}4.4m$, square(間) of $1{\times}1{\sim}2{\times}1$. The building material was stone and located below or near the signal-fire stand.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.590-596
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• 2020

The fabric used for military winter inner clothing(top) is quilted with padded cotton to provide warmth. This quilting fabric is generally manufactured with yarns that intersect and are sewn substantially between the fabric and cotton. Thus, it is impossible to separate the fabric and cotton once after the quilting fabric is manufactured, which can result in a significant loss of fabric and cotton when separated. In this study, after fabricating the quilting fabric, we investigated a method to stabilize change rate of thickness and increase the warmth keeping property through subsequent processing without damaging the fabric. A relatively method of passing the quilting fabric through a part of the cotton production facility was used generally, and the following results were obtained. This indicates that after the quilting fabric was manufactured, the warmth keeping property was improved through the subsequent processing steps, so that the change rate of thickness due to washing was stabilized.

• Journal of Environmental Science International
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• v.26 no.9
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• pp.1031-1043
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• 2017

Recently severe drought caused the water shortage around the western parts of Chungcheongnamdo province, South Korea. A Diversion tunnel from the Geum river to the Boryong dam, which is the water supply dam for these areas has been proposed to solve this problem. This study examined hydraulic impacts on the Geum river associated with the diversion plan assuming the severe drought condition of 2015 would persist for the simulation period of 2016. The hydraulic simulation model was verified using hydrologic and hydraulic data including hourly discharges of the Geum river and its 8 tributaries, fluctuation of tidal level at the mouth of the river, withdrawals and return flows and operation records of the Geum river barrage since Feb. 1, 2015 through May 31, 2015. For the upstream boundary condition of the Geum river predicted inflow series using the nonlinear regression equation for 2015 discharge data was used. In order to estimate the effects of uncertainty in inflow prediction to the results total four inflow series consisting of upper limit flow, expected flow, lower limit flow and instream flow were used to examine hydraulic impacts of the diversion plan. The simulation showed that in cases of upper limit and expected flows there would be no problem in taking water from the Geum river mouth with a minimum water surface level of EL(+) 1.44 m. Meanwhile, the simulation also showed that in cases of lower limit flow and instream flow there would be some problems not only in taking water for water supply from the mouth of the Geum river but also operating the diversion facility itself with minimum water surface levels of EL(+) 0.94, 0.72, 0.43, and 0.14 m for the lower limit flow without/with diversion and the instream flow without/with diversion, respectively.

• Journal of Environmental Health Sciences
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• v.17 no.1
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• pp.136-162
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• 1991

This thesis is a study on the change and the process of the development of the hygiene administration during the period of modernization of our nation which promoted by the open door policy of our country chiefly under the pressure of the foreign countries. During that period Korea had reorganized the old political system radically and introduced the western medical system. Through the close study of literature concerning the system of the hygiene administration, the laws of health and hygiene, the environmental sanitation organizations and their practical activities the author obtained the conclusions as following 1. The government passed around 40 laws of health and hygiene from the time when the bureau of hygiene was founded in 1894 to the annex of Korea to Japan. Most of the laws were believed to be established by the enforecement of Japanese government. When the epidemics were prevailing, a decree for the prevention of the epidemics was proclaimed by the Japanese president of the headquarters of national police. It is shown well that the sovereignty of Korea had been deprived. 2. After the armex of Korea to Japan, the hygiene police and the general police belonging to the bureau of national police shared the tasks of health and hygiene. This was a temporary system which had existed just during the colonial period. As for the water-supply which is the most important facility among the various environmental hygiene facilities, the rate of supply was remarkably high in Japanese rather than in Korean. 3. During the period of American military administration, it is notable that the division of hygiene in the bureau of national police was replaced by the bureau of hygiene. This period is regarded as the turning point when hygiene administration was operated by means of education along with the introuction of American system of public health. 4. Ever since the foundation of the republic government, the laws of health and hygiene which had been established during the colonial period have been put into operation without rriuch change except several regulations concerning food.

• Composites Research
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• v.23 no.2
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• pp.17-23
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• 2010

The stealth technology can increase the survivability of aircrafts or warships and enhance the capability of mission completion in hostile territory. The purpose of this paper is to present the low observable structure with curved surfaces made by fiber-reinforced composites and to show the possibility of developing omnidirectional stealth platforms for military applications. In this study, we developed a radar absorbing structures(RAS) based on a circuit analog absorber to reduce the radar cross section(RCS) of an object with curved surfaces. Firstly, the RAS with a periodic square patterned conducting polymer layer was designed and simulated using a commercial 3-D electromagnetic field analysis program. Secondly, the designed semi-cylindrical structure with low RCS was fabricated using fiber-reinforced composites and conducting polymer. To make the periodic pattern layer, acts as resistive sheet, the intrinsic conducting polymer paste containing PEDOT with a polyurethane binder was used. Finally, the radar cross section was measured to evaluate the radar absorbing performances of the fabricated RAS by the compact range facility in POSTECH.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.1
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• pp.98-104
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• 2016

With the development of modern science and technology, weapon systems such as tanks, submarines, combat planes, radar are also dramatically advanced. Among these weapon systems, the ballistic missile, one of the asymmetric forces, could be considered as a very economical means to attack the core facilities of the other country in order to achieve the strategic goals of the country during the war. Because of the current ballistic missile threat from the North Korea, establishing a missile defense (MD) system becomes one of the major national defense issues. This study focused on the optimization of air defense artillery units' deployment for effective ballistic missile defense. To optimize the deployment of the units, firstly this study examined the possibility of defense, according to the presence of orbital coordinates of ballistic missiles in the limited defense range of air defense artillery units. This constraint on the defense range is originated from the characteristics of anti-ballistic missiles (ABMs) such as PATRIOT. Secondly, this study proposed the optimized mathematical model considering the total covering problem of binary integer programming, as an optimal deployment of air defense artillery units for defending every core defense facility with the least number of such units. Finally, numerical experiments were conducted to show how the suggested approach works. Assuming the current state of the Korean peninsula, the study arbitrarily set ballistic missile bases of the North Korea and core defense facilities of the South Korea. Under these conditions, numerical experiments were executed by utilizing MATLAB R2010a of the MathWorks, Inc.

• Korean Security Journal
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• no.53
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• pp.255-279
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• 2017

The development of North Korea's nuclear weapons has worsened to the sixth nuclear test in 2017, and despite the sanctions of the international community including our government, we have not been able to offer clear solutions and alternatives, and the current measures are not enough in case of North Korea is using nuclear weapons. This study suggests how we should be prepared against the use of nuclear weapons under the premise that North Korea will never give up development of nuclear weapons under any circumstances. The first chapter outlines the current status of our preparedness if North Korea makes a nuclear attack. The second chapter analyzes and evaluates the power of nuclear weapons and North Korea's nuclear weapons threat. In the third chapter, we analyze North Korea nuclear attack and analyze the wartime emergency situation and civil defense posture. Finally, in order to implement the solutions presented in the text, we will identify priorities and summarize further developments.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.713-716
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• 2010

Slosh and vibration effects of fuel inside of fuel tank can be occurred due to the acceleration and flight speed during the rotorcraft flight. It can lead to the failure of internal fuel component and fuel tank skin can be damaged. This is directly related to human survival. Military specification (MIL-DTL-27422D) specifies that stability of aircraft fuel tank and internal component against slosh &vibration load shall be verified through the qualification test procedures. This report shows the establishment of slosh and vibration test facility and KUH fuel tank qualification test result.