• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.221-226
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• 2000

Hot air heater with light oil burner is the most common heater for greenhouse heating in the winter season in Korea. However, since the thermal efficiency of the heater is about 80∼85%, considerable unused heat amount in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The heat recovery system is made for plant bed or soil heating in the greenhouse. The system consisted of a heat exchanger made of copper pipes, ${\Phi}12.7{\times}0.7t$ located in the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tank. The total heat exchanger area is 1.5$m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to the performance test it could recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690\ell$/hr from the waste heat discharged. The exhaust gas temperature left the heat exchanger dropped to $100^{\circ}C$ from $270^{\circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{\circ}C$ from $21^{\circ}C$ at the water flow rate of $690\ell$/hr. By the feasibility test conducted in the greenhouse, the system did not encounter any difficulty in operations. And, the system could recover 220,235kJ of exhaust gas heat in a day, which is equivalent of 34% of the fuel consumption by the water boiler for plant bed heating of 0.2ha in the greenhouse.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.328-336
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• 2016

Purpose: The heat culture areas of greenhouses have been continuously increasing. In the face of international oil price fluctuations, development of energy saving technologies is becoming essential. To save energy, auxiliary heat source and thermal insulation technologies are being developed, but they lack cost-efficiency. The present study was conducted to save energy by developing a conceptually new semi-basement type greenhouse. Methods: A semi-basement type greenhouse, was designed and constructed in the form of a three quarter greenhouse as a basic structure, which is an advantageous structure to inflow sunlight. To evaluate the performance of the developed greenhouse, a similar structured general greenhouse was installed as a control plot, and heating tests were conducted under the same crop growth conditions. Results: Although shadows appeared during the winter in the semi-basement type greenhouse due to the underground drop, the results of crop growth tests indicated that there were no differences in crop growth and development between the semi-basement type greenhouse and the control greenhouse, indicating that the shadows did not affect the crop up to the height of the crop growing point. The amount of fuel used for heating from January to March was almost the same between the two greenhouses for tests. The heating load coefficients of the experimental greenhouses were calculated as $3.1kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the semi-basement type greenhouse and $2.9kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the control greenhouse. Since the value is lower than the double layer PE (polyethylene) film greenhouse value of $3.5kcal/m^2{\cdot}^{\circ}C{\cdot}h$ from a previous study, Tthe semi-basement type greenhouse seemed to have energy saving effects. Conclusions: The semi-basement type greenhouse could be operated with the same fuel consumption as general greenhouses, even though its underground portion resulted in a larger volume, indicating positive effects on energy saving and space utilization. It was identified that the heat losses could be reduced by installing a thermal curtain of multi-layered materials for heat insulation inside the greenhouse for the cultivation of horticultural products by installing thermal curtain of multi-layered materials for heat insulation inside the greenhouse, it was identified that the heat losses could be reduced.

• Parasites, Hosts and Diseases
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• v.32 no.3
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• pp.171-176
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• 1994

Wistar rats were induced of Pneumowstis cayinii infection by injection with methyl-prednisolone to correlate the cyst counts and numbers of nuclei. Seven sections of the lungs were examined by impression smears and also whole lung homogenates were screened for nucleus counting for each rat. At the first week of the experiment, all of the Impression smears except one were cyst negative but trophic forms were counted around 106. At the third week, the cysts appeared one per 20 Immersion oil lens fields. The nuclei were on the order of 107 at this period, and this amount of Pc is regarded as the limit of cyst detection on Impression smears. When the nuclei were over 109 in the lungs, the cysts were counted about 50 in 20 microscopic fields. The organisms were distributed in the lungs without any predilection focus. The present data suggest that the trophic forms, proliferate first and the cysts appear later in the lungs.

• International Area Studies Review
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• v.16 no.3
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• pp.293-321
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• 2012

This study aims to examine how institutions has been formed to deepen interdependence and to keep check in trade on the border regions of East Sea Rim between the macro structure and micro behaviors. The transitional nations such as China, Russia, and North Korea adjacent to the East Sea Rim exhibits unique characteristics in terms of transaction governance structure. While the regional economy in northeast China is still overwhelmed by the stated-owned enterprises(SOEs), it strongly encourages the private economic trade to form institutional economy through the border trade port and peddler trade market. Thus trade is shaped by the mixed governance. In far east Russia, whereas the SOEs are in charge of exporting oil, gas etc., private firms and small scale traders are importing household items, so that it can also be called as the mixed governance, while informal social networks simultaneously work. In North Korea, for the trade, since the firms are mainly required to have the permits from the different levels of government, it is regarded as the hierarchical governance. The institutional economics seems to well explain the changing agencies and their influence on the trade among the regions in the East Sea Rim.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.1
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• pp.85-92
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• 2021

The stratum corneum is formed from keratinocytes and intercellular lipids, with ceramide as the main component of intercellular lipids. Ceramides are one of the important components of the intercellular lipids to form a lamellar structure, but they are insoluble and therefore are not suitable for direct application to the skin. Thus, it was intended to apply ceramide to the formulation of pluronic lecithin organogel (PLO gel), which received constant attention among drug delivery systems. A suitable oil for formulation was selected and a PLO gel containing ceramide was manufactured. Liquid crystal formation and variation were observed using polarized microscopes, and viscoelastic analysis was performed to find out the viscoelastic behavior of the PLO gel. Small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) analysis were performed to confirm the structures in the formulation. Results showed that the size and stability of the liquid crystal differed depending on the content ratio of ceramide and lecithin in the PLO gel containing ceramide. Furthermore, viscoelastic analysis showed the stability of the formulation, and SAXS/WAXS analysis confirmed that the PLO gel without ceramide had hexagonal structure of the quadrilateral system array, and the PLO gel with ceramide had the lamellar structure of the quadrilateral system array.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.18-31
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• 2021

Linoleum is a resilient, hygienic, and eco-friendly floor covering. It was developed in England by Frederick Walton in 1863. Made of cork flour, linseed oil, and burlap as its main materials, the flexible and waterproof linoleum became globally popular in the early 20th century. Unlike the vinyl coverings, the burlap-backed linoleum was used not only in commercial spaces but also in household areas like kitchens, bathrooms, and even living rooms. As a global product, linoleum was imported and used in Korean palaces like Deoksugung and Changdeokgung in the early modern period. According to the record Deoksugung Won-Ahn, linoleum was applied to the major buildings, including Hamnyeongjeon, Deokhongjeon, and Jeonggwanheon, and various other venues. The linoleum used in these places are mainly monochrome blue and brown color, which probably means that they are from England. The trade records in the early 20th century show that linoleum was imported mainly from England and America. The Ewangjik building floor plan in the Changdeokgung Palace shows that linoleum was used extensively. There are even some originals, which were laid in 1920 and left in the Changdeokgung Palace. When Daejojeon and Huijeongdang were rebuilt in 1920, the interior was outfitted with western features and linoleum was used in areas such as bathrooms, the tonsorial parlor, and one of the rooms on the west side of Huijeongdang. In situ in the Daejojeon and Huijeongdang areas in the Changdeokgung Palace are monochrome, patterned black, and stylized floral tile patterned, which are closely similar to American products made by ALC and Armstrong company. This study will help us better understand linoleum's characteristics, its uses and the material itself. It will also form the basis for the restoration of Changdeokgung Palace as well as other modern interiors with linoleum flooring in the future.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.403-410
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• 2020

The purpose of this study was to determine whether olfactory stimulation would improve spasticity, balance ability and quality of life in stroke patients. Twenty-one stroke patients were recruited and were randomly divided into two groups: olfactory stimulation group (n=10) and sham stimulation group (n=11). Participants in both groups received conventional physical therapy for 30 minutes before the intervention. Additionally, subject in the olfactory stimulation group performed olfactory stimulation using lavender oil for 6 minutes (2 minx3 set), five times a week for two weeks, while the sham stimulation group conducted olfactory stimulation using water for the same amount of time. Composite-Spasticity-Score was used to assess spasticity level of ankle plantar-flexors. Dynamic balance was measured using a TUG. Postural-sway distance was measured using a force platform. Quality of life were measured by SF-36. There was no significant difference within group and between the groups in the spasticity. Significant improvement in postural-sway and TUG were observed in the olfactory stimulation group compared to the sham stimulation group (p<0.05). The Mental Componnt Summary of the SF 36 in the olfactory stimulation group improved significantly greater than the sham stimulation group (p<0.05). Our findings indicate that olfactory stimulation is beneficial and effective to improve balance ability and quality of life in stroke patients.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.503-516
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• 2021

Autonomous fire detection and suppression system requires advanced technology for complex detection technology and injection/control technology for accurate hitting by fire location. Also, foam spraying should be included to respond to oil fires. However, when a single spray monitor is used in common, water and foam spray properties appear different, so for accurate fire suppression, research on the spray trajectory and distance will be required. In this study, experimental studies and numerical analysis studies were combined to analyze the foam spray characteristics through the spray monitor developed for the establishment of an autonomous fire extinguishing system. For flow analysis of foam injection, modeling was performed using OpenFOAM analysis software, and the commonly used foaming agent (Aqueous Film-Forming Foam) was applied for foam properties. The injection distance analysis was performed according to the injection pressure and the injection angle according to the form of the foam, and at the same time, the results were verified and presented through the injection experiment.

• Journal of Korean Home Economics Education Association
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• v.34 no.2
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• pp.115-128
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• 2022

Soseon means a table setting without meat and fish. It seems to have been influenced by Buddhism and is mentioned in Joseon Dynasty records. This study aimed to investigate the use of Soseon and its relationship with Buddhism in Joseon, which emphasized Confucianism and refused Buddhism. This study was conducted on the Joseon Dynasty Annals database and records of royal food literature during the Joseon Dynasty. In Joseon, Soseon was seen in 186 cases and its cases were found during the early days than the late days of the same Dynasty. It was carried out at funerals for subjects and relatives(61.82%). national ceremonies(21.51%), envoy receptions(11.29%), and auspicious ceremony(5.38%). Meat dishes were replaced by tofu, seaweed, rice cakes, and cookies in the Soseon for national rituals. The table setting of Soseon consisted of a main dish, side dishes, and desserts. A comparison of the Soseon table setting between Gilrye and Hyungrye showed Chae, Gaejang and Dasik belonged only Gilrye table setting. The major food was Noodles, Tang, Chae, Yumilgwa, Yugwa, Dasik, rice cakes and fruits. Soseon menu was cooked flour, tofu, seaweed, shiitake, pine nut, sesame oil, honey, etc. Tofu, flour, and seaweed were referred to in the documents in relation to Buddhism. This study shows that the Soseon is a vegetarian diet form in Joseon affected by Buddhism from Goryeo. Therefore, this study is expected to be used as basic data for the study of Buddhist food culture of royal rituals in the Joseon Dynasty.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.5
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• pp.449-463
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• 1990

To obtain the basic informations on quality improvement, seed protein and amino acid composition were analyzed in 460 strains of perilla germplasm. Among the tested strains, total protein content ranged from 17.9% to 28.1 % with the 23.6% of varietal means. Form the experiment, Namji, Sandong, and Eunjin were selected as high protein strains of which content was as high as 28.1%. In protein content, collected strains from Jeonnam province showed highest, and was not significantly different by maturity, but this characteristics showed differences by seed coat color and 1,000 seed weight. The significantly negative correlation was observed between protein content and seed setting ratio. However it was observed that significant and high positive correlation between protein and oil content. A calibration for an Infra-Alyzer 450 using log reflectance readings at 2208, 1982, 1940 and 1722nm could be used without adjustment for the measurment of the protein content in perilla with a standard deviation of differences against micro-kjeldahl of 0.27%. The amino acid composition of perilla was similar to the other oilseed crops, and showed a relatively high lysine and methionine content. Further, amino acid composition of perilla seed was exellently characterized with bal ance and higher than FAO recommendation. Major amino acids were indentified as a glutamic acid and arginine in perilla seed protein.