• Journal of the Korean Society of Food Science and Nutrition
• /
• v.20 no.3
• /
• pp.266-271
• /
• 1991

The salted and dried mullet roe was manufactured by the conventional processing method. The processing conditions were the salting with soybean sauce of 10% NaCl, 1.2cm of thickness, 3m/sec of air velocity, 70% of RH and $20^{\circ}C$ of wind-drying temperature for 20 days. The fractional compositions of free and bound lipids were classified in neutral, Glyco - and phospholipids of the processed roe. The fatty acid content of glycolipids was measured during processing and storage. Major fatty acids of glycolipids were $C_{16:0},\;C_{18:1}\;and\;C_{18:2}$ whose total amount was 7.71mg/100mg occupying 77% of the total fatty acids of glycolipids. The ratio of unsaturated fatty acid to the saturated fatty acid of bound glycolipids was 2.09 and that of free glycolipids was as low as about 0.92. The rations of the polyenoic acids to the monoenoic acids were very low as 0.10-0.78. The essential fatty acids of bound glycolipids were 4.32mg/100mg and a very much decreased content of 1.46mg/100mg at 9 week storage time.

• KIEAE Journal
• /
• v.13 no.5
• /
• pp.89-96
• /
• 2013

Green roofs can reduce surface water runoff, provide a habitat for wildlife moderate the urban heat island effect, improve building insulation and energy efficiency, improve the air quality, create aesthetic and amenity value, and preserve the roof's waterproofing. Green roofs are mainly divided into three types : intensive, simple-intensive, and extensive. Especially, extensive roof environment is a harsh one for plant growth; limited water availability, wide temperature fluctuations, high exposure to wind and solar radiation create highly stressed environment. This study, aimed at extensive green roof, was carried out on the rooftop of the library at Seoul Women's Univ. from October to November, 2012 and from March to August, 2013. To suggest the most effective vegetation model for biodiversity and heat island mitigation, surface temperatures were monitored by each vegetation model. We found that herbaceous plants of Aster sphathulifolius, Aceriphyllum rossii and Belamcanda chinensis, shrub of Syringa patula 'Miss Kim', Thymus quinquecostatus var. japonica, Sedum species can mixing each other. Among them, the vegetation models including Sedum takesimense, Aster sphathulifolius, Thymus quinquecostatus var. japonica was more effective on the surface temperature mitigation, because the species have the tolerance and high ratio of covering, and also in water. Especially, in the treatment of bark mulching, they helped to increase the temperature of vegetation models. In the case of summer, temperature mitigation of vegetation models were no significant difference among vegetation types. Compared to surface temperature of June, July and August were apparent impact of temperature mitigation, it shows that temperature mitigation are strongly influenced by substrate water content.

• Aerospace Engineering and Technology
• /
• v.3 no.2
• /
• pp.217-228
• /
• 2004

This paper presents the rotating test techniques and the results of the roating test of the small-scaled hingeless rotor system with composite paddle blades in hover and forward flight conditions. The small-scaled rotor system was designed using froude-scaled properties of full scale rotor system. Metal flexures and composite flexures were made as hub flexures by the same dynamic properties of rotor system. The rotating tests of hingeless rotor system installed in GSRTS at KARI were carried out to get lead-lag damping ratios and aerodynamic loads of the hingeless rotor system. MBA(Moving Block Analysis) technique was used for the estimation of lead-lag damping ratio. 6-components balance was installed between hub and main shaft and straingauges on blades were instrumented for the measurements of aerodynamic loads of rotor system. Tests were performed on the ground and in the wind tunnel according to the test conditions of hover and forward flight, respectively.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.22 no.4
• /
• pp.551-561
• /
• 1998

This paper was studied to understand the characteristics of heat transfer coefficients and surface temperature distributions around a circular combustion chamber within the heat-intercept duct of kerosene fan heater. The experiment was carried out in the heat-intercept duct of kerosene fan heater attached to the blow-down-type subsonic wind tunnel with a test section of 240 mm * 240 mm * 1200 mm. The purpose of this paper was to obtain the basic data related with normal combustion for new design from conventional kerosene fan heater, and to investigate the effect of surface temperature, local and mean heat transfer coefficients versus flow-rate of convection axial fan according to the variations of heat release conditions from kerosene fan heater during normal combustion. Consequently it was found that (i) the revolution of convection axial fan during combustion had a smaller value than that of non-combustion because of the thermal resistance due to the high temperature in the heat-intercept duct, (ii) the pressure ratio P$_{2}$/P$_{1}$ had a comparatively constant value of 0.844 according to the revolution increase of turbo fan and the heating performance of kerosene fan heater had a range of 1,494 ~ 3,852 kcal/hr, (iii) the local heat transfer coefficient around a circular combustion chamber had a comparatively larger scale in the range of 315 deg. < .theta. < 45 deg. than that in the range of 90 deg. < .theta. < 270 deg. as a result of heat transfer difference between front and back of a circular combustion chamber, and (iv) the mean heat transfer coefficient around a circular combustion chamber increased linearly like a H$_{m}$=95.196Q+104.019 in condition of high heat release according to the increase of flow-rate of axial fan.n.

• Wind and Structures
• /
• v.23 no.2
• /
• pp.109-125
• /
• 2016

Flow interference is investigated between two tripped cylinders of identical diameter D at stagger angle ${\alpha}=0^{\circ}{\sim}180^{\circ}$ and gap spacing ratio $P^*$ (= P/D) = 0.1 ~ 5, where ${\alpha}$ is the angle between the freestream velocity and the line connecting the cylinder centers, and P is the gap width between the cylinders. Two tripwires, each of diameter 0.1D, were attached on each cylinder at azimuthal angle ${\beta}={\pm}30^{\circ}$, respectively. Time-mean drag coefficient ($C_D$) and fluctuating drag ($C_{Df}$) and lift ($C_{Lf}$) coefficients on the two tripped cylinders were measured and compared with those on plain cylinders. We also conducted surface pressure measurements to assimilate the fluid dynamics around the cylinders. $C_D$, $C_{Df}$ and $C_{Lf}$ all for the plain cylinders are strong function of ${\alpha}$ and $P^*$ due to strong mutual interference between the cylinders, connected to six interactions (Alam and Meyer 2011), namely boundary layer and cylinder, shear-layer/wake and cylinder, shear layer and shear layer, vortex and cylinder, vortex and shear layer, and vortex and vortex interactions. $C_D$, $C_{Df}$ and $C_{Lf}$ are very large for vortex and cylinder, vortex and shear layer, and vortex and vortex interactions, i.e., the interactions where vortex is involved. On the other hand, the interference as well as the strong interactions involving vortices is suppressed for the tripped cylinders, resulting in insignificant variations in $C_D$, $C_{Df}$ and $C_{Lf}$ with ${\alpha}$ and $P^*$. In most of the (${\alpha}$, $P^*$ ) region, the suppressions in $C_D$, $C_{Df}$ and $C_{Lf}$ are about 58%, 65% and 85%, respectively, with maximum suppressions 60%, 80% and 90%.

• Korean journal of applied entomology
• /
• v.10 no.1
• /
• pp.43-48
• /
• 1971

This experiment was conducted to determine the most effective type of Bight·trap for pine catepillar moths (Dendrolimus spectabilis B.) and to investigate the environmental factors affecting the attractiveness of the moths.. The various types of light traps made used of: black light, white light, fluorescent light, yellow light, and red light and the environmental factors considered were rainfall, wind velocity and collecting time. All the traps were operated from 8 in the evening to midnight. The results obtained are summarized as follows; The most effective attraction of moths ($62\%$ of total number attracted) was observed with blacklight-lamp and the most abundant attraction of the moths was found from 8 to 10 in the evening. Attractiveness in terms of sex ratio attracted from 8 to 10 in the evening was found to the .approximately 7 female to 1 male, Environmental factors considered were found to have no influences in attractiveness of the moths in this experiment.

• Horticultural Science & Technology
• /
• v.31 no.2
• /
• pp.239-245
• /
• 2013

Occupational exposure and risk assessment were conducted to evaluate the safety of operators when insecticide acetamiprid was applied to apple orchard using a speed sprayer. Dermal patches, cotton gloves, socks, and masks were used to monitor the dermal exposure, and personal air pump with solid sorbent was used to measure the potential inhalation exposure. In validation to analytical methods, the limit of detection and limit of quantitation were 0.25 ng and 1 ng, respectively. Good reproducibility (coefficient variation < 4%), linearity (coefficient determination > 0.999), and recovery (85.3-118.2%) were obtained. Trapping efficiency of solid sorbent was 96.4% while breakthrough did not occur. Only hand exposure was measured on the gloves during mixing/loading to give $33-1,132{\mu}g$. Exposure amount of operator 3 among 4 workers was noticeably high. The total volumes of spray liquid for operators were $535-1,235mL{\cdot}h^{-1}$, corresponding to 0.03-0.08% of the applied spray solution. Highest contaminated parts of body were thighs, chest, and lower legs. The inhalation exposure ratio to the total application amount was significantly low. However, wind seemed to affect the inhalation exposure of operator. For risk assessment, margin of safety was calculated by the application of cloth and dermal penetration rate to obtain values of much larger than 1 in all cases. Therefore, health risk of operators during treatment of acetamiprid in apple orchard could be of least possibility.

• Journal of Ocean Engineering and Technology
• /
• v.27 no.4
• /
• pp.76-82
• /
• 2013

Motion reduction of an offshore structure at resonant frequency is essential for avoiding critical damage to the topside and mooring system. A damping plate has a distinct advantage in reducing the motion of a floating structure by increasing the added mass and the damping coefficient. In this study, the heave motion responses of a circular cylinder with an impermeable and a permeable damping plate attached at the bottom of the cylinder were investigated thru a model test. The viscous damping coefficients for various combinations of porosity were obtained from a free-decay test by determining the ratio between any pair of successive amplitudes. Maximum energy dissipation occurred at a porous plate with a porosity P = 0.1008. Experimental results for regular and irregular waves were compared with an analytical solution by Cho (2011). The measured heave RAO and spectrum reasonably followed the trends of the predicted values. A significant motion reduction at resonant frequency was pronounced and the heaving-motion energy calculated by the integration of the area under the heave motion spectrum was reduced by more than 75% by the damping plate. However, additional energy dissipation by eddies of strong vorticity and flow separation inside a porous damping plate was not found in the present experiments.

• Journal of Oral Medicine and Pain
• /
• v.42 no.4
• /
• pp.89-101
• /
• 2017

Purpose: The purpose of this study is to investigate the prevalence of temporomandibular disorders (TMDs) in children and adolescents, their characteristic contributing factors, the characteristic features of symptoms and symptoms, and the response to treatment. Methods: We studied the researches, that were the results of the searches for words such as temporomandibular disorder, TMD, children, adolescents, and juvenile through PubMed and DBpia. Results: According to a study conducted in Busan, the ratio of adolescents increased from 18.3% to 21% in 2008 compared to 2000, and the proportion of boys increased from 38.58% to 45.38%. One of the characteristic contributing factors for adolescents is the macrotrauma such as jaw trauma, vehicle accidents, sports, physical abuse, forceful intubation, and third molar extraction. The second is a microtrauma from parafunctional habit such as bruxism, clenching, hyperextension, wind instrument, and fingernail biting that can cause joint overload, cartilage breakdown, synovial fluid alterations, and other changes within the joint. The diagnosis of TMDs in juvenile adolescents is not significantly different from that of adults. Medical history, clinical examination and radiological examinations are required. Conclusions: In the temporomandibular joint history and assessment, all comprehensive dental history examination is required, including head and neck pain, mandibular dysfunction, previous orofacial trauma, history of present illness with an account of current symptoms. For the treatment and management of temporomandibular arthritis in juvenile adolescents, understanding the characteristics of TMDs in juvenile adolescents and thoroughly analyzing appropriate diagnosis and possible contributing factors through comprehensive history taking & examination, conservative treatment, including fast and active cautions education, will be essential.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.6
• /
• pp.468-477
• /
• 2014

In this research, how a solar powered HALE (high altitude long endurance) UAV (Unmanned Aerial Vehicle) can climb and reach mission altitude, 18km, starting from the ground using only solar energy. A glider type aircraft was assumed as a baseline configuration which has wing area of $35.98m^2$ and aspect ratio of 25. Configuration parameters, lift and drag coefficients were calculated using OpenVSP and XFLR5 that are NASA open source programs, and climb flights were predicted through energy balance between available energy from solar power and energy necessary for a climb flight. Minimum time climb flight was obtained by minimizing flight velocities at each altitude and total time and total energy consumption to reach the mission altitude were predicted for different take off time. Also, aircraft moving distances due to westerly wind and flight speed were calculated.