• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.1
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• pp.33-39
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• 2007

This paper is aimed at the development of a software that predicts the surface temperature profiles of three-dimensional objects on the ground by considering the spectral solar radiation through the atmosphere. The spectral solar radiation through the atmosphere is modeled by using the well-known LOWTRAN7 code which analyzes the detailed spectral transmission characteristics by considering the atmospheric gas layers. In this paper, the transient temperature distribution over a cylinder is calculated by using the semi-implicit method. The spectral radiative surface properties such as the absorptivity and emissivity of the objects are used to model the effects of the solar irradiation and the surface emission. Both the detailed spectral modeling and the simple total modeling for the solar radiation absorption show fairly good agreement with each other by showing less than 3% difference in surface temperature.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.2
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• pp.124-130
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• 2016

The aim of this study was to suggest the future direction of diagnostic and evaluative pattern identification questionnaire (PIQ) by reviewing the state of development and utilization of PIQ according to Korean classification of disease-U (KCD-U). We surveyed the database of OASIS, NDSL, KISS, DBPIA, and Pub-med to know the kinds of developed and developing PIQ of Korean medicine. We used 'Pattern Identification' and 'Questionnaire' to find suitable papers. The inclusion criteria met 47 cases. The number of PIQ before 2000yrs, between 2001 to 2005, 2006-2010, 2011-2015 were 2, 5, 18, 22cases. The number of PIQ belonged to the disease of Korean medicine, the pathological symptom of korean medicine, the Sasang constitutional pattern identification and etc according to KCD-U were 20(42.6%), 8(17%), 9(19.1%) and 10(21.3%). Twenties among forty seven PIQ were validated, and the rest of them were not validated. The distribution of the numbers of PIQ were significantly different according to KCD-U (p=0.003). The direction of Utilization of PIQ was 36 questionnaires in diagnosing PI, 14 cases in evaluating health state, 4cases in evaluating effects of a treatment and 8 ones in diagnosing Sasang constitutional types. This study reveals the status on validated and non-validated PIQ of Korean medicine and suggests the basic information for the direction of developing PIQ in the future.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.8
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• pp.749-754
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• 2010

Knowledge of the characteristics of airflow in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. In our laboratory, a series of experimental investigations on the nasal airflow was conducted; airflow in models of normal and deformed nasal cavities under both constant and periodic flow conditions was studied by PIV. Some of the patients with asymmetric nasal cavities experience pain or discomfort, while other patients with asymmetric nasal cavities do not experience pain. Airflows inside asymmetric nasal cavities with and without obstructions due to a bent nasal septum are investigated both experimentally by PIV and numerically by using the general-purpose FVM code in order to determine the reason for the above-mentioned discrepancy. The comparisons between two cases are tried. Heat and humidity distribution are investigated numerically.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.6
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• pp.481-486
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• 2011

The evaluation of supercooled water droplet impingement characteristics of full-scale aircraft components in wind tunnels under icing conditions has been severely limited by the relative size of the component and the test facility. The concept of truncated airfoil sections has been suggested in order to extend the operational range of icing tunnels. With proper deflection of the small trailing-edge flap on the truncated airfoil the local pressure distribution may remain very close to that of the full-scale airfoil. In this study the shape of a truncated flapped airfoil is investigated for various deflection angles. To validate the truncated flapped airfoils, air flow and collection efficiency over the truncated airfoil are compared with the results of the full-scale airfoil obtained from the state-of-the-art icing simulation code.

• Journal of Biosystems Engineering
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• v.38 no.2
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• pp.87-94
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• 2013

Purpose: Pineapple is now the third most important tropical fruit in world production after banana and citrus. Phytosanitary irradiation is recognized as a promising alternative treatment to chemical fumigation. However, most of the phytosanitary irradiation studies have dealt with physiochemical properties and its efficacy. Accurate dose calculation is crucial for ensuring proper process control in phytosanitary irradiation. The objective of this study was to optimize phytosanitary irradiation treatment of pineapple in various radiation sources using Monte Carlo simulation. Methods: 3-D geometry and component densities of the pineapple, extracted from CT scan data, were entered into a radiation transport Monte Carlo code (MCNP5) to obtain simulated dose distribution. Radiation energy used for simulation were 2 MeV (low-energy) and 10 MeV (high-energy) for electron beams, 1.25 MeV for gamma-rays, and 5 MeV for X-rays. Results: For low-energy electron beam simulation, electrons penetrated up to 0.75 cm from the pineapple skin, which is good for controlling insect eggs laid just below the fruit surface. For high-energy electron beam simulation, electrons penetrated up to 4.5 cm and the irradiation area occupied 60.2% of the whole area at single-side irradiation and 90.6% at double-side irradiation. For a single-side only gamma- and X-ray source simulation, the entire pineapple was irradiated and dose uniformity ratios (Dmax/Dmin) were 2.23 and 2.19, respectively. Even though both sources had all greater penetrating capability, the X-ray treatment is safer and the gamma-ray treatment is more widely used due to their availability. Conclusions: These results are invaluable for optimizing phytosanitary irradiation treatment planning of pineapple.

• Explosives and Blasting
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• v.34 no.3
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• pp.10-16
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• 2016

Recently, transition from open pit to underground mining in limestone mines is an increasing trend in Korea due to environmental issues such as noise, dust and vibrations caused by crushers and equipment. The severe damages in the surrounding rock mass of underground opening caused by explosive blasting may lead to rock fall hazards or casualties. It is well known that variables which mainly affect blast-induced rock falls in underground mining are: blast vibration level, joint orientation and distribution and shape of the cross sections of underground structures. In this study, UDEC program, which is a DEM code, is used to simulate blast vibration-induced rock fall in underground openings. Variation of joint space, joint angle and joint normal stiffness was considered to investigate the effect of joint characteristics on the blast vibration-induced rock fall in underground opening. Finally, jointed rock mass models considering blast-induced damage zone were examined to simulate the critical blast vibration value which may cause rock falls in underground opening.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.295-304
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• 2017

The Ramsar protected area in Ungok wetland, which has been designated since 2011, was described by syntaxonomy and synchorology. Phytocoenon was identified and named by a traditional method of the $Z{\ddot{u}}rich$-Montpellier School and Code of Phytosociological Nomenclature. Habitat-based vegetation classification has identified into twelve syntaxa consisting of 88 taxa in seven vegetation types: Juncus effusus var. decipiens-Salix koreensis community, Caricis-Salicetum subfragilis, Galium spurium var. echinospermon-Phragmites japonica community, Phragmitetum australis, Scirpetum fluviatilis, Leersia japonica-Typha angustifolia community, Juncus diastrophanthus-Juncus effusus var. decipiens community, Leersicetum japonicae, Nymphoido indicae-Trapetum japonicae (typicum, marsiletosum quadrifoliae subass. nova hoc loco, variante Euryale ferox), Nelumbo nucifera community, Utricularia tenuicaulis community, Potamogetonetum crispi. Actual vegetation map was made by using topographical map of scale 1 : 5,000. Habitat-based management on the Ungok wetland vegetation was required, in which there are composed of two major areas such as the back-swamp vegetation and the limnetic vegetation zone.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2917-2923
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• 2015

The three dimensional inelastic response characteristics of the standard school buildings depending on hysteresis models are reviewed. Three artificial earthquake records in accordance with KBC(Korea Building Code) are used and the inelastic response characteristics such as story shear force, story drift ratio, story displacement, hinge distribution state are reviewed with four hysteresis models. As results, story shear force is increased by maximum 27% and story drift ratio is increased by maximum 30% according to hysteresis models. Modified Takeda Model shows maximum story shear and story drift raio in longitudinal and short direction, expecting higher safety. Story shear shows minimum value with Clough Model in both directions and story drift ratio shows minimum with Takeda model in longitudinal and with Clough model in short direction, so these models are expected to decrease the safety ratio.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.9
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• pp.27-34
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• 2004

A computational study on the supersonic flow around the lateral jet controlled missile has been performed. For this purpose a three dimensional Navier-Stokes computer code(AADL3D) has been developed and case studies have been performed by comparing the normal force coefficient and the moment coefficient of a missile body for several parameters such as angles of attack, circumferential jet positions, and spouting jet angles. Missile surface is divided into four regions with respect to the center of gravity, and the normal force and moment distribution at each region are compared. The results show different behavior of the normal force and moment variation according to each parameter. Furthermore, it is shown that the pitching moment can be minimized through proper combination of each parameter.

• The Journal of Korean Medicine
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• v.36 no.3
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• pp.98-110
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• 2015

Objectives: The purpose of this study was to analyze the medical cost of facial paralysis in payer perspective and to estimate the practice pattern of patient using 2011 Health Insurance Review & Assessment Service-National Patients Sample(HIRA-NPS). Methods: Basic statistical system was used for descriptive analysis of NPS dataset. A table for general information (table20) was extracted by disease code, and social demographic characteristics, distribution of the use among inpatients and outpatients, utilization of each kind of medical care institutions, medical cost were analyzed. Subgroup analysis was conducted for assuming the practice pattern of korean medicine and western medicine. Results: A total of 8,219 people and 64,345 claims data were identified as having facial paralysis. Proportion of outpatient was 95.23%, inpatient 0.84% and patient using both services 3.93%. Mean patient charges was 44,229 won per outpatient, 178,886 won per inpatient and 523,542 won per patient using both services. Utilization of korean medical care institutions was 68.81%(claims), 40.46%(patients), utilization of western medical care institutions was 31.19%(claims), 59.54%(patients). The amount charged by korean medical care institutions was 52.61% and western medical care institutions was 47.39%. Cost per claim was higher than those of the korean treatment and cost per patient of western treatment was lower than those of the korean treatment. Conclusions: The research assessed the medical cost and practice pattern associated with facial paralysis. These findings could be used in health care policy and subsequent studies.