• Membrane Journal
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• v.23 no.1
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• pp.12-23
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• 2013

On the subject of river bed water in Seomjin river, it had accomplished the verifying experiment of membrane filtration pilot plant for evaluating the applicability of its process throughout the prediction of membrane fouling as a function of the pore size of membrane and the determination of optimum coagulant dosage. On the result of the experiment for the evaluation of the membrane fouling as a function of the pore size, a increasing rate of irreversible resistance of membrane pore size $0.1{\mu}m$ and $0.01{\mu}m$ was measured each $0.44{\times}10^{12}/m^2$ and $0.42{\times}10^{12}/m^2$, respectively. And on the result of Flux-test, it showed that the optimum coagulant dosage was measured lower than the it of the Jar-test. The result to be operated in a condition of a permeate flux $1.0{\sim}1.5m^3/m^2{\cdot}day$ without coagulation and a permeate flux $1.0{\sim}2.0m^3/m^2{\cdot}day$ with coagulation was maintained at stable trans-membrane pressure (TMP) value for 6 months up to. Therefore it showed that the stable operation without the coagulation was possible on permeate flux $1.0{\sim}1.5m^3/m^2{\cdot}day$ in the operation of membrane filtration process.

• Korean Security Journal
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• no.32
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• pp.123-150
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• 2012

The purpose of this study was to seek practical intelligences for certain persons who wish to be a guard by studying for what practical public guards' recognition of organization and vocation is. The results of this study were as follows. First, Six study participants presented 'Respect within members', 'Atmosphere like family', 'Premium members', and 'Economic compensation & wealth of budget' as essential requirements for the best guard organization. Second, they also presented 'Systematic daily task & training', 'Exact selection system', and 'Strong cohesion & teamwork' as strong points of their organization. Third, they mentioned 'Internal evaluation system', 'Lack of education contents', and 'Limited position circulation' as weak points of their organization. Fourth, they mentioned that they feel encouraged itself as they work in the best guard organization, while they were skeptical when the citizens did not cooperate with them and they were not fully rewarded for their injury. Fifth, they expressed 'Difficulty of business cooperation', 'Unstable living patterns', 'Inconsistent assessment', and 'Continuing tension' as difficulties for performing the duties and stress causes. Lastly, they recognized of job security and self-esteem as they work in the best guard organization as advantages of a job, while they recognized of controlled life, low salaries and welfare level compared to duty importance and risks as disadvantages of a job. Consequently, students who wish to be a guard should consider job and organization attributes and set their career goals refer to these results.

• Journal of Energy Engineering
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• v.13 no.2
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• pp.118-127
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• 2004

The purpose of this study is experimentally to analyze that intake port swirl, injection system and turbocharger have an effect on the engine performance and the emission characteristics in a V8 type turbocharged intercooler D.I. diesel engine of the displacement 16.7ι, and to suggest the improvement of engine performance. Generally to enhance engine power, TCI diesel engine is put to practically use turbo-charged intercoler in order to increase boost efficiency which is cooled boost air. As results of considering the factors of the intake port of swirl ratio 2.25, compression ratio 17.5, re-entrant 8.5$^{\circ}$ combustion bowl, nozzle hole diameter ${\Phi}$0.33*3+${\Phi}$0.35*2, nozzle protrusion 3.18mm, injection timing BTDC 12$^{\circ}$CA and turbo charger (compressor 0.6A/R+46Trim, turbine 1.0A/R+57Trim) is the best in the full range of operating in the engine performance and the exhaust characteristics of NO$\_$x/ concentration. Therefore their factors are appropriated as intake system, injection and turbocharger system.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.118-127
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• 2010

Resistivity logging instruments are designed to measure the electrical resistivity of a formation, and this can be directly interpreted to provide a water-saturation profile. However, resistivity logs are sensitive to borehole and shoulder-bed effects, which often result in misinterpretation of the results. These effects are emphasised more in the presence of tool eccentricity. For precise interpretation of short- and long-normal logging measurements in the presence of tool eccentricity, we simulate and analyse eccentricity effects by combining the use of a Fourier series expansion in a new system of coordinates with a 2D goal-oriented high-order self-adaptive hp finite-element refinement strategy, where h denotes the element size and p the polynomial order of approximation within each element. The algorithm automatically performs local mesh refinement to construct an optimal grid for the problem under consideration. In addition, the proper combination of h and p refinements produces highly accurate simulations even in the presence of high electrical resistivity contrasts. Numerical results demonstrate that our algorithm provides highly accurate and reliable simulation results. Eccentricity effects are more noticeable when the borehole is large or resistive, or when the formation is highly conductive.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.10
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• pp.971-977
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• 2012

It is well known that the performance of a diesel injector is directly related to the power, emission, and fuel consumption of the diesel combustion engine. In this study, the injection response characteristics of CRDi injectors driven by a solenoid coil and a piezoceramic were investigated by using the AMESim simulation code. Some analytical parameters such as the fuel pressure and hole diameter were considered. From this study, it was shown that the piezo-driven injector had a faster response and had better control capability than the solenoid-driven injector. In addition, it was found that the piezo-driven injector can be utilized more effectively in a multiple injection scheme than a solenoid-driven injector.

• Tunnel and Underground Space
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• v.12 no.4
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• pp.248-258
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• 2002

The sixth underground pumped powerhouse cavern is now under construction in Korea. For the stability analysis for the caverns of the five underground powerhouses, finite element method was used. For the analysis, in-situ rock stress were measured by overcoring method. The stress measurement showed that initial horizontal to vertical stress ratio was 1.07-1.32 in low powerhouse sites. Rock mass strength and elasticity were assumed from rock core properties through engineering processes. So the ratio of input elasticity fur the analysis were about 0.16-0.55 to rock core elasticity. In most of the analysis, elasto-plastic condition with Mohr-Coulomb failure criteria were applied. But in one case, viscoelastic condition was applied, too. The input cohesion and internal friction angle were approximately 0.12-0.22, 0.6-0.87 to rock core strength parameters, respectively.

• The Journal of Natural Sciences
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• v.6 no.1
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• pp.103-108
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• 1993

Zeolites were discovered as a natural mineral more than two hundred ago. In the beginning, the mineral was used as ion-exchange material and adsorbent. After the end of World War II , however, a variety of zeolites have become available in large amounts because of the establishment of low temperature synthesis and the discobery of natural zeolite deposits of sedimentary origin. Various uses of xeolite were developed utilizing the unique crystal strucrure and function of these minerals. In connection with this development remakable progress has also been made in basic stuides on the related geology and mineralogy, crystallization from sols and gels, structure, ion exchange, adsorption and cataiysis. As a result, zeolites, which had been known only as mineral specimens displayed in museums. established a firm position among the high-technology masterials with excellent functional capabilities.

• Journal of Broadcast Engineering
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• v.26 no.1
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• pp.61-69
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• 2021

Image outpainting is a very interesting problem in that it can continuously fill the outside of a given image by considering the context of the image. There are two main challenges in this work. The first is to maintain the spatial consistency of the content of the generated area and the original input. The second is to generate high quality large image with a small amount of adjacent information. Existing image outpainting methods have difficulties such as generating inconsistent, blurry, and repetitive pixels. However, thanks to the recent development of deep learning technology, deep learning-based algorithms that show high performance compared to existing traditional techniques have been introduced. Deep learning-based image outpainting has been actively researched with various networks proposed until now. In this paper, we would like to introduce the latest technology and trends in the field of outpainting. This study compared recent techniques by analyzing representative networks among deep learning-based outpainting algorithms and showed experimental results through various data sets and comparison methods.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.09a
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• pp.55-71
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• 2005

Jeju Island is mainly composed of basaltic lava flows and subordinate amounts of volcaniclastic sedimentary rocks. Jeju Province operates the monitoring wells for seawater intrusion problems around Jeju Island to evaluate of groundwater resources in coastal area. Various surveys and monitoring have been performed in boreholes, and also conventional geophysical well loggings conducted to identify basalt sequences and assess seawater intrusion problems. Various conventional geophysical well logs, including radioactive logs, electrical log, caliper log, and temperature and conductivity log and heat-pulse flowmeter log were obtained in 29 boreholes. The results of geophysical well loggings for saturated rocks are interesting and consistent. Natural gamma logs are useful in basalt sequences to sedimentary interbeds, unconsolidated U formation, and seoguipo formation with higher natural gamma log regardless of saturated or unsaturated basalts. Neutron logs are very effective to discriminate among individual lava flows, flow breaks, and sedimentary interbeds in saturated formation. In hyalocastite, porosity is high and resistivity is low, and we think that hyalocastite is a major pathway of fluid flow. In trachybasalt, porosity has a wide range and resistivity is high. In sedimentary interbeds, unconsolidated U formation and seoguipo formation, porosity is high and resistivity is low. The temperature logs in eastern area in Jeju are useful to interpret the hydrogeological unit and evaluate seawater intrusion in Suan area.

• Korean Security Journal
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• no.33
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• pp.229-260
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• 2012

The purpose of this study is to categorize the past Chiefs of Presidenteal Security Service so far based on their level of expertise and authority so that we can identify some specific reasons as to why some of them are recognized as successful while others are not, and that the categorization will be a guideline to future successful administration. In order to do so, a quantitative research has been implemented through meetings of a group security science expert who has been in security business for substantial amount of time. The result is as following: Authoritative/professional: 2nd Chief of P.S.S. Park, Jong-Gyu, 5th Chief of P.S.S. Jang, Se-Dong, 7th Chief of P.S.S. Lee, Hyeon-Wu, 8th Chief of P.S.S. Choi, Seok-Rip. Authoritative/Non-professional: 1st Chief of P.S.S. Hong, Jong-cheol, 3rd Chief of P.S.S. Cha, Ji-cheol, 6th Chief of P.S.S. Ahn, Hyeon-Tae, 14th Chief of P.S.S. Kim, In-Jong. Non-authoritative/professional: 4th Chief of P.S.S. Jeong, Dong-Ho, 9th Chief of P.S.S. Park, Sang-Beom, 13th Chief of P.S.S. Yom. Sang-Guk. Non-authoritative/Non-professional: 10th Chief of P.S.S. Kim, Gwang-Seok, 11th Chief of P.S.S. Ahn, Ju-Seop, 12th Chief of P.S.S. Kim, Se-Ok. This categorization research on the Chief of P.S.S. suggests that any president, to be a successful one, must choose the Chief of P.S.S. based on his/her expertise in order to secure national security.