• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.728-737
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• 2019

In this study, the minimized on-board computer (OBC) module for integrated navigation is developed, which provides satellites' relative position information in formation flying and cluster operation situations. The scalability is considered to apply the user-selected wireless communication module and Global Positioning System (GPS) receiver for navigation, while considering to meet the structural design standard of nano-satellites. As a result of the product development and production, the processing speed of integrated navigation and real-time data synchronization is satisfied for cluster operation nano-satellites by using micro controller unit (MCU). From a heat/vacuum, vibration and radiation test, the OBC was confirmed to be operated in space environments. From these results, a mass production system of OBC was made which is a key part of development on satellite formation flying and cluster/constellation missions that the community demands are increasing.

• Nuclear Engineering and Technology
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• v.41 no.4
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• pp.531-544
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• 2009

This paper is intended to provide key issues and current research outcomes on accelerator-based Boron Neutron Capture Therapy (BNCT). Accelerator-based neutron sources are efficient to provide epithermal neutron beams for BNCT; hence, much research, worldwide, has focused on the development of components crucial for its realization: neutron-producing targets and cooling equipment, beam-shaping assemblies, and treatment planning systems. Proton beams of 2.5 MeV incident on lithium target results in high yield of neutrons at relatively low energies. Cooling equipment based on submerged jet impingement and micro-channels provide for viable heat removal options. Insofar as beam-shaping assemblies are concerned, moderators containing fluorine or magnesium have the best performance in terms of neutron accumulation in the epithermal energy range during the slowing-down from the high energies. NCT_Plan and SERA systems, which are popular dose distribution analysis tools for BNCT, contain all the required features (i.e., image reconstruction, dose calculations, etc.). However, detailed studies of these systems remain to be done for accurate dose evaluation. Advanced research centered on accelerator-based BNCT is active in Korea as evidenced by the latest research at Hanyang University. There, a new target system and a beam-shaping assembly have been constructed. The performance of these components has been evaluated through comparisons of experimental measurements with simulations. In addition, a new patient-specific treatment planning system, BTPS, has been developed to calculate the deposited dose and radiation flux in human tissue. It is based on MCNPX, and it facilitates BNCT efficient planning based via a user-friendly Graphical User Interface (GUI).

• Journal of Animal Reproduction and Biotechnology
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• v.38 no.2
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• pp.84-88
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• 2023

Because multiple ovulation embryo transfer (MOET) in cattle includes several benefits such as wide spreading of genetically superior offspring for long distance, this biotechnological method has been widely applied to Hanwoo. When the recipients are not stayed close after embryo recovery from donor, the embryos are moved to other farms via several vehicles (car, train, and airplane). However, air travel induces lesser oxygen level, increased vibration, lower air pressure, higher noise, and increased exposure of cosmic radiation to living things than ground level. It was still unknown that fresh embryos obtained from multiple ovulation of Hanwoo could maintain their fertility after being transported via air plane, the present case report introduced a clinical case of MOET in Hanwoo after shipping fresh embryos via air transportation. The donor was multi-ovulated via follicle-stimulating hormone series of injection, which was followed by a gonadotrophin-releasing hormone injection and artificial insemination twice. The embryos were recovered by the uterine flushing, packed in ministraws, transported to recipients for 6 h including 1 h air flight, and then transferred to the synchronized recipients. During pregnancy diagnosis of early gestation period, 5 of 7 recipients (71.4%) presented no heat signs and showed fetal sacs with fluid under transrectal ultrasonography. After normal gestation period, all recipients naturally delivered healthy calves (male n = 2 and female n = 3) without abortion, stillbirth, and premature birth. The present case report indicated that transportation of fresh embryos for MOET via domestic flight in Korea did not affect to their fertility.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.2
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• pp.175-179
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• 2006

Welders are exposed to a number of hazards including metal fumes, toxic gases, electricity, heat, noise, and radiation such as ultraviolet and infrared light. We encountered a patient who developed non-cardiogenic pulmonary edema within a day after cutting copper pipe with an oxyethylene torch. The patient was a 26-year-old welder. He complained of dyspnea, generalized myalgia, and febrile sensation the following morning. The patient's chest X-ray and chest CT scan showed extensively distributed and ill-defined centrilobular nodules. Both his symptoms and chest X-ray abnormalities improved spontaneously. We attributed the patient's symptoms to non-cardiogenic pulmonary edema due to nitrogen dioxide, reasoning that: 1) the pipe consisted only of copper, according to material safety data sheet (MSDS); 2) a previous report in the literature demonstrated increased nitrogen dioxide levels under similar conditions; 3) the patient's clinical course and radiologic findings were very reminiscent of non-cardiogenic pulmonary edema following accidental exposure to nitrogen dioxide.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.5
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• pp.474-480
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• 2011

Space Imaging Sensor operated on LEO is affected from the Earth IR and Albedo as well as the Sun Radiation. The Imaging Sensor exposed to extreme environment needs thermal control subsystem to be maintained in operating/non-operating allowable temperature. Generally, units are periodically dissipated on spacecraft panel, which is designed as radiator. Because thermal design of the imaging sensor inside a spacecraft is isolated, heat pipes connected to radiators on the panel efficiently transfer dissipation of the units. First of all, preliminary thermal design of radiating area and heater power is performed through steady energy balance equation. Based on preliminary thermal design, on-orbit thermal analysis is calculated by SINDA, so calculation for thermal design could be easy and rapid. Radiators are designed to rib-type in order to maintain radiating performance and reduce mass. After on-orbit thermal analysis, thermal requirements for Space Imaging Sensor are verified.

• Journal of the Korea Fashion and Costume Design Association
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• v.16 no.4
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• pp.229-235
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• 2014

This study conducted a research on burn-out printing convergence technology for cellulose blend knit fabrics. Printing technology, which forms color pattern on the fabric, can be generally classified into four according to printer or printing method, e.g. screen printing, roller printing, rotary printing, digital printing. However, these printing methods are flat in design or pattern, which have limitation to overcome monotonousness of fabric, so that recently burn-out process method, which expresses three-dimensional pattern effect by treating chemical on the surface of fabric as the method to appeal its esthetics to the customers. Particularly, in case of cellulose/polyester composite material, first, it is proceeded in 2 processes, by dyeing cellulose or polyester fabric and burning out cellulose fabric, in this process, due to pollution caused by disperse dye migration, color of polyester fabric part could be discolored, which has high falt risk. This research considered coloring burn-out technique, which simultaneously proceed dyeing and burn-out by reducing dyeing and burn-out process to 1 stage, which were proceeded in 2 stages previously. As the research result, it was confirmed that reasonable depth of roller was 0.04~0.06mm in roller printing process, heat treatment condition of burn-out far-infrared radiation was $185^{\circ}C{\times}30m/min$. Color fastness to washing was confirmed to be 4-5 grade, color fastness to rubbing, 3-4 grade, color fastness to light, 4 grade. Also, it was confirmed that energy reduction effect appeared 38.19%, in case of energy cost per yard compared to the existing production, also, 19.74%, in case of production cost.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.6
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• pp.158-169
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• 2004

A method for predicting the short-term dynamic line ratings in overhead transmission lines using real-time weather forecast data is proposed in this paper. Through some inspections for the 3-hour interval forecasting factors such as ambient temperature, wind speed grade and weather code given by KMA(Korea Meteorological Administration), correlation properties between forecast weather data and actual measured data are analyzed. To use these variable in determining the dynamic line ratings, they are changed into suitable numerical values. Furthermore adaptive neuro-fuzzy systems to improve reliabilities for wind speed and solar heat radiation ate designed It was verified that the forecast weather data can be used to predict the line rating with reliable. As a result it can be possible that the proposed predicting system can be effectively utilized by their anticipation a short-time in advance.

• Journal of Dairy Science and Biotechnology
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• v.23 no.2
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• pp.93-98
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• 2005

Effects of heat and gamma irradiation on chemical, microbiological, and immunological changes of raw milk were compared. Free fatty acid content of milk showed increasing tendency according to the increase of heating temperature and irradiation dose, and showed similarity in UHT (ultra high temperature) and 5 kGy irradiation. Total bacterial counts and coliforms were not detected after treatment of LTLT (low temperature long time), HTST (high temperature short time), UHT, and irradiation from 1 to 10 kGy in the milk with initial microbial load at $10^3$ CFU/mL initially, but after 7 day storage, were not detected in UHT milk and that irradiated at 3 kGy or above. Heat treatment decreased (p<0.05) arginine, asparate, iso-leucine, lysine, and methionine content compared to raw milk while irradiation decreased (p<0.05) asparate, histidine, iso-luecine, leucine, and lysine content, which means irradiation could change primary structure of milk proteins. It was concluded that f kGy gamma irradiation treatment of raw milk could give a similar effect to UHT treatment in chemical and microbiological viewpoint, and may reduce allergenicity of raw milk.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.848-852
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• 2012

Vegetation can make not only to lower the urban ambient air temperature (UAAT) by crop evapotranspiration (ET) and increasing solar radiation albedo, but also to reduce the urban air pollution by $CO_2$ uptake and $O_2$ emission in addition to the reducing ozone concentrations by aid of lower the UAAT. To evaluate the effect of vegetation on urban heat island mitigation (UHIM), the climate change of 6 cities during 30 years are analysed, and the amount of ET, $CO_2$ uptake, $O_2$ emission and ozone concentrations are estimated in Korea. The most hot season is the last part of July and the first part of August, and the highest average UAAT of a period of ten days was $35.03^{\circ}C$ during 30 years (1979 - 2008). The mean values of maximum ET of rice and soybean in urban area during urban heat island phenomena were 6.86 and $6.00mm\;day^{-1}$, respectively. The effect of rice and soybean cultivation on lowering the UAAT was assessed to be 10.5 and $3.0^{\circ}C$ in Suwon, respectively, whereas the differences between the UAAT and canopy temperature at urban paddy and upland in Ansung were 2.6 and $2.2^{\circ}C$. On the other hand, the urban-garden in Suwon city had resulted in lowering the UAAT and the surface temperature of buildings to 2.0 and $14.5^{\circ}C$, respectively. Furthermore, the amounts of $CO_2$ uptake by rice and soybean were estimated to be 20.27 and $15.54kg\;CO_2\;10a^{-1}day^{-1}$, respectively. The amounts of $O_2$ emission by rice and soybean were also assessed to be 14.74 and $11.30kg\;O_2\;10a^{-1}day^{-1}$, respectively. As other cleaning effect of air pollution, the ozone concentrations could be also estimated to reduce 21.0, 8.8, and 4.0 ppb through rice-, soybean cultivation, and urban gardening during most highest temperature period in summer, respectively.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.155-162
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• 1995

To find out the relationship between duration of sunshine and mean air temperature, monthly climatic data were analyzed in several locations in Korea. Even though mean air temperature was high in summer, duration of sunshine was shorter than winter in Kangneung. Net radiation showed a positive correlation with duration of sunshine and its regression coefficient was the highest in July. An increasing rate of sensible heat flux according to the increment of sunshine hours was significantly high in April and October, but was low in July. In spring and fall, duration of sunshine was positively correlated with the daily temperature difference, but in summer and winter it was negatively correlated with maximum temperature and with the minimum temperature, respectively. In January, one hour increase in sunshine hour lowered the mean air temperature by 1 to $1.7^{\circ}C$.