• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.2
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• pp.63-75
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• 2013

The Inner Port Phase 2 area of the Pyeongtaek-Dangjin Port is enclosed by a total of three permeable sea-walls, and the disposal site to the east of the Inner Port Phase 2 is also enclosed by two permeable sea-walls. The maximum tidal range measured in the Inner Port Phase 2 and in the disposal site in May 2010 is 4.70 and 2.32 m, respectively. It reaches up to 54 and 27%, respectively of 8.74 m measured simultaneously in the exterior. Regression formulas between the difference of hydraulic head and the rate of interior water volume change, are induced. A three-dimensional numerical hydrodynamic model for the Asan Bay is constructed incorporating a module to compute water discharge through the permeable sea-walls at each computation time step by employing the formulas. Hydrodynamics for the period from 13th to 27th May, 2010 is simulated by driving forces of real-time reconstructed tide with major five constituents($M_2$, $S_2$, $K_1$, $O_1$ and $N_2$) and freshwater discharges from Asan, Sapkyo, Namyang and Seokmoon Sea dikes. The skill scores of modeled mean high waters, mean sea levels and mean low waters are excellent to be 96 to 100% in the interior of permeable sea-walls. Compared with the results of simulation to obstruct the flow through the permeable sea-walls, the maximum current speed increases by 0.05 to 0.10 m/s along the main channel and by 0.1 to 0.2 m/s locally in the exterior of the Outer Sea-wall of Inner Port. The maximum bottom shear stress is also intensified by 0.1 to 0.4 $N/m^2$ in the main channel and by more than 0.4 $N/m^2$ locally around the arched Outer Sea-wall. The module developed to compute the flow through impermeable seawalls can be practically applied to simulate and predict the advection and dispersion of materials, the erosion or deposion of sediments, and the local scouring around coastal structures where large-scale permeable sea-walls are maintained.

• Journal of Digital Convergence
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• v.12 no.4
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• pp.201-211
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• 2014

This study is to identify whether a difference exists between factors that influence the time when independently owned nail shops and franchises commence business. Futhermore, we set out to investigate the criteria for nail shop owners use when selecting franchise nail shops with a relatively high level of customer satisfaction and performance, to discuss the necessity of a franchise agreement. An actual analysis has revealed that there is a difference in factors that influence management at the time of and after the inception of independently owned shops and franchise nail shops. Business performance of franchise shops, as a result of evaluating customer satisfaction or monthly sales, turns out to be higher than independently owned shops. The criteria for selecting franchise stores includes intensity of competitiveness in the same business district, accessibility, ability to keep up with current trends, directors' skills, color scheme, excellence of company logo, interesting interior, reasonable prices compared to the level of cosmetic procedure and efforts to motivate employees. Overall, the deciding factor enabling shops to operate continuously is constant supervision from the headquarters of the franchise company.

• Journal of Korean Society of Archives and Records Management
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• v.4 no.2
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• pp.1-22
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• 2004

This study is about the paper of Mulberry(桑紙). The paper which was usually applied to the ancient bookpaper and documents. But there is a rare record about it today. So the paper was made from the Mulberry(뽕나무) bast fiber using traditional handcraft method. and Paper Mulberry(닥나무) by traditional method. And tested by physical and optical methods in comparisons with Paper Mulberry(닥나무). The ratio of length/width of Mulberry fiber was 475, and its lignin content was lower than the Paper Mulberry. The Mulberry paper had similar forming properties and physical strength to the Paper Mulberry fiber. Therefore, the Mulberry fiber seem to be a good paper fiber for traditional paper. For the aging test, in the thermal acceleration treatment for 72 hours and 144 hours at the temperature of $105^{\circ}C$ incubator, the Mulberry paper was more deteriorative than the Paper Mulberry. In the ultraviolet acceleration treatment for 100 hours and 200 hours the Mulberry paper was less interior to the Paper Mullberry, in the increase of treatment time. And the Mulberry paper was approved to be a good traditional paper in appearance. Furthumore, in considing the sample of bred Mulberry species grown today, its paper is thought to be superio to the paper of Paper Mulberry in symptom of senility in natural ultraviolet light.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.215-225
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• 2015

Recently, the importance of energy saving and alternative energy is significantly increasing due to energy depletion and the phase change material (PCM) research for saving energy is also actively investigating. In this research, the membrane emulsification using SPG membrane was used to make various microencapsulated phase change material (MPCM) particles which were comprised of $Rubitherms^{(R)}$ (RT-21 and RT-24) core and silica coating. We investigated the pressure of the dispersion phase, the concentration of surfactant, and the ratio of $Rubitherm^{(R)}$ and silica to prepare various MPCM particles. The DSC and TGA were used to examine the heat stability and latent heat properties. Also, PSA, SEM, and optical microscopy were used to confirm the size of $Rubitherm^{(R)}$ particles and the thickness of silica shell. The average of particle size was $7-8{\mu}m$. And, FT-IR was also used to enforce the qualitative analysis. Finally, the MPCM particles obtained from membrane emulsification showed monodispersed size distribution and the heat stability and latent heat were kept up to 80% compared to pure $Rubitherm^{(R)}$. So, it can be effectively used for wallpaper, buildings and interior products for energy saving as PCMs.

• Journal of the Korean association of regional geographers
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• v.9 no.4
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• pp.519-533
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• 2003

The U.S. Conservation Reserve Program (CRP) resulted in the conversion of approximately 14.8 million ha(36.5 million acres) of cropland to grassland, woodland, and other conservation uses throughout the U.S. between 1986 and 1992. One of the major results of CRP has been the addition of millions of hectares of potential wildlife habitat. primarily as grassland. In this study, we examined regional changes in landscape structure caused by the introduction of CRP. Utilizing multi-seasonal Landsat Thematic Mapper imagery, we produced maps of cropland and grassland for the pre- and post- CRP enrollment periods for a six-county region in southwest Kansas. We then applied post-classification differencing to identify regions of cropland that had been converted to CRP. Using the FRAGSTATS spatial pattern analysis program, we calculated a variety of spatial statistics to analyze changes in landscape structure due to CRP. The major impact of CRP in the six-county study area has been the reversal of an overall trend of grassland habitat fragmentation. From the standpoint of potential wildlife habitat, the introduction of CRP has greatly increased the number of patches, mean patch size, and the interior or core area of grassland patches. In addition, CRP has increased connectivity and aggregation between grassland patches, potentially important factors for species of conservation interest, particularly those that require larger expanses of unbroken habitat. Finally, the distance between neighboring patches of grassland has decreased, reducing travel distance between patches. Clearly, the introduction of CRP has substantially modified the spatial structure of the southwest Kansas landscape, with important implications for wildlife habitat.

• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.64-76
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• 2013

In this study, eco-friendly hybrid composite boards were manufactured from green tea, three kinds of charcoals and wood fiber for developing interior materials to reinforce the strength performances and the functionalities in addition to performances of the green tea-wood fiber hybrid boards. The effects for the kind and the component ratio of raw materials on mechanical properties were investigated. Bending strength performances of hybrid composite boards were highest in the hybrid composite boards composed of green tea, fine charcoal and wood fiber on average. However, the difference caused by the kind of charcoals was not large. These values were was markedly improved than those of green tea - wood fiber hybrid composite boards reported in previous researches. And it was found that the bending strength performance decreased with increasing component ratios of green tea and charcoals. The difference between urea resins used as the binder showed the higher value in hybrid composite boards using $E_1$ grade urea resin than in those using $E_0$ grade urea resin, but the difference between hybrid composite boards manufactured by both resins decreased markedly than the green tea - wood fiber hybrid composite boards reported in previous research. The internal bond strength of hybrid composite boards was in the order of hybrid composite boards with fine charcoal, activated charcoal and black charcoal, and it was found that the hybrid composite boards with fine charcoal had a similar values to control boards composed of only wood fiber.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.111-121
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• 2018

RIn this research, digital elevation models, true-ortho image and 3-dimensional digital complied data was generated and evaluated using unmanned aircraft vehicle stereoscopic images by applying photogrammetric principles. In order to implement stereoscopic vision, digital Photogrammetric Workstation should be used necessarily. For conducting this, in this study GEOMAPPER 1.0 is used. That was developed by the Ministry of Trade, Industry and Energy. To realize stereoscopic vision using two overlapping images of the unmanned aerial vehicle, the interior and exterior orientation parameters should be calculated. Especially lens distortion of non-metric camera must be accurately compensated for stereoscope. In this work. photogrammetric orientation process was conducted using commercial Software, PhotoScan 1.4. Fixed wing KRobotics KD-2 was used for the acquisition of UAV images. True-ortho photo was generated and digital topographic map was partially produced. Finally, we presented error analysis on the generated digital complied map. As the results, it is confirmed that the production of digital terrain map with a scale 1:2,500~1:3,000 is available using stereoscope method.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.2
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• pp.127-134
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• 2020

High supersonic aircraft are exposed to high temperature environments by aerodynamic heating during supersonic flight. Thermal protection system structures such as double-panel structures are used on the skin of the fuselage and wings to prevent the transfer of high heat into the interior of an aircraft. The thin-walled double-panel skin can be exposed to acoustic loads by supersonic aircraft's high power engine noise and jet flow noise, which can cause sonic fatigue damage. Therefore, it is necessary to examine the behavior of supersonic aircraft skin structure under thermal-acoustic load and to predict fatigue life. In this paper, we designed and fabricated thermal-acoustic test equipment to simulate thermal-acoustic load. Thermal-acoustic testing of the titanium specimen under thermal-acoustic load was performed. The analytical model was verified by comparing the thermal-acoustic test results with the finite element analysis results.

• Journal of the Korean Society of Costume
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• v.55 no.5 s.95
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• pp.108-119
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• 2005

The objective of the study is was investigate the condition of the battle dress uniform worn by male members of the Korean Police Special Weapons Attack Team(KP-SWAT), identify problems, and provide basic raw materials for developing improved design of BDU. For this purpose, the researcher conducted a questionnaire survey on 92 male members of SWAT (Special Weapon Attack Team) units in Seoul using a questionnaire developed through observation and interview. Also, the body sizes of male SWAT members were measured. According to the results of body size measurements, male SWAT members generally require uniforms with a target bust girth, armhole, biceps circumference, thigh and calf circumference, longer jacket length, sleeve length, and trouser length to the knee. According to the results of the questionnaire survey, they reported dissatisfaction with the fit. In addition, they said that the Pockets are positioned too low for convenient use. Many subjects reported that their trousers were too short because of the rubber rings at the bottom of the legs. In addition, many subjects requested the alteration of the inconveniences caused by the designs finished with velcro on the bottom collar of the upper uniform, the marks and ensigns of the upper uniform, the bottom of the upper and lower uniform, and several pockets. Furthermore, there were many complaints concerning how they had to wear their uniform. The most frequently worn out and the body parts most often injured in field training and operations, they were reported, on the upper uniform, as the elbow, collar, neck, armpit, shoulder, and sleeve hem in that order, and on the lower uniform, the knee, interior calf, waist (belt rings), buttocks (rear pockets), and the bottom of the trousers (ankle) in that order As for questions concerning priorities in the improvements of the operational uniform and preferred design, the subjects recommended improvement in safety (protectiveness), workability (motional flexibility), design (shape), fit (size), comfort, ease in terms of putting on and taking off, etc., and the majority preferred two-piece designs ($67.4\%$), followed by one-piece ($30.4\%$), or both ($2.2\%$).

• Horticultural Science & Technology
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• v.32 no.4
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• pp.473-483
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• 2014

In this work, the effects of shade combination, shade height and wind regime on greenhouse climate were quantified. A two-dimensional (2-D) computational fluid dynamics (CFD) model was developed based on an 11-span plastic greenhouse in eastern China for wind almost normal to the greenhouse orientation. The model was first validated with air temperature profiles measured in a compartmentalized greenhouse cultivated with mature lettuce (Lactuca sativa L., 'Yang Shan'). Next, the model was employed to investigate the effect of shade combinations on greenhouse microclimate patterns. Simulations showed similar airflow patterns in the greenhouse under different shade combinations. The temperature pattern was a consequence of convection and radiation transfer and was not significantly influenced by shade combination. The use of shade screens reduced air velocity by $0.02-0.20m{\cdot}s^{-1}$, lowered air temperature by $0.2-0.8^{\circ}C$ and raised the humidity level by 0.9-2.0% in the greenhouse. Moreover, it improved the interior climate homogeneity. The assessment of shade performance revealed that the external shade had good cooling and homogeneity performance and thus can be recommended. Furthermore, the effects of external shade height and wind regime on greenhouse climate parameters showed that external shade screens are suitable for installation within 1 m above roof level. They also demonstrated that, under external shade conditions, greenhouse temperature was reduced relative to unshaded conditions by $1.3^{\circ}C$ under a wind speed of $0.5m{\cdot}s^{-1}$, whereas it was reduced by merely $0.5^{\circ}C$ under a wind speed of $2.0m{\cdot}s^{-1}$. Therefore, external shading is more useful during periods of low wind speed.