• Journal of Biosystems Engineering
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• v.43 no.1
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• pp.21-29
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• 2018

Purpose: The objective of this study is to evaluate the performance of the conical solar concentrator (CSC) system, whose design is focused on increasing its collecting efficiency by determining the optimal conical angle through a theoretical study. Methods: The design and thermal performance analysis of a solar concentrator system based on a $45^{\circ}$ conical concentrator were conducted utilizing different mass flow rates. For an accurate comparison of these flow rates, three equivalent systems were tested under the same operating conditions, such as the incident direct solar radiation, and ambient and inlet temperatures. In order to minimize heat loss, the optimal double tube absorber length was selected by considering the law of reflection. A series of experiments utilizing water as operating fluid and two-axis solar tracking systems were performed under a clear or cloudless sky. Results: The analysis results of the CSC system according to varying mass flow rates showed that the collecting efficiency tended to increase as the flow rate increased. However, the collecting efficiency decreased as the flow rate increased beyond the optimal value. In order to optimize the collecting efficiency, the conical angle, which is a design factor of CSC, was selected to be $45^{\circ}$ because its use theoretically yielded a low heat loss. The collecting efficiency was observed to be lowest at 0.03 kg/s and highest at 0.06 kg/s. All efficiencies were reduced over time because of variations in ambient and inlet temperatures throughout the day. The maximum efficiency calculated at an optimum flow rate of 0.06 kg/s was 85%, which is higher than those of the other flow rates. Conclusions: It was reasonable to set the conical angle and mass flow rate to achieve the maximum CSC system efficiency in this study at $45^{\circ}$ and 0.06 kg/s, respectively.

• Culinary science and hospitality research
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• v.22 no.8
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• pp.219-225
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• 2016

This study was conducted to investigate the amount of fat, vitamins and minerals in milk can be affected by hydrodynamic cavitation since cavitation is recently focused on as one of the sterilization methods. Vitamins (vitamin A, $B_2$), minerals (Ca, P, Mg, Zn) and fat contents were measured according to Ministry of Food and Drug Safety's Processing Standards and Component Specifications of Animal Product. Vitamin A & $B_2$ contents decreased approximately 23% & 19%, respectively after cavitation. Minerals content showed no change after cavitation. Also, P and Mg contents were reduced after cavitation to 2 mg/100g and 0.1 mg/100g, showing no change. Milk fat content was 3.46% before cavitation and 3.41% after cavitation, displaying no difference. Hydrodynamic cavitation process displays a possibility to replace existing pasteurizing method, as it does not change vitamin or mineral contents in milk. Therefore, a more clear and systematic research on hydrodynamic cavitation pasteurization is needed to distribute excellent quality milk and to emphasize physiochemical properties and quality change of existing heat pasteurization process.

• Journal of Dairy Science and Biotechnology
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• v.38 no.2
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• pp.89-98
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• 2020

The purpose of this study was to investigate the probiotic properties of lactic acid bacteria (LAB) isolated from a Korean traditional food kimchi. Gram staining was performed by Macrogen (Macrogen, Inc.) for identification of the LAB. Five strains of LAB were identified, including DKGF9 (Lactobacillus plantarum), DKGF1 (L. paracasei ), DKGF8 (L. casei ), DK207 (L. casei ), and DK211 (L. casei ). The biological activities of the isolated strains were assessed. The results showed that heat resistance of the strains was similar to or higher than the commercial strain L. acidophilus LA-5. Indirect testing of the ability of the strains to attach to the mucin layer revealed that DKGF9, DKGF1, and DKGF8 have high binding affinities for the mucous layer. All strains showed antimicrobial activity similar to or higher than the commercial strain LA-5. In proteolysis experiments, the diameters of proteolysis zones of the five strains increased in the period of 24-72 h, with DKGF1 exhibiting the largest zone diameter. Three strains were selected based on their antioxidant activities. Among the five isolated strains, L. paracasei DKGF1 showed potential probiotic activity, and thus, it may be useful for the development of health-promoting products.

• Journal of Haehwa Medicine
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• v.9 no.1
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• pp.745-761
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• 2000

Literatural study for Delirious speech and Fading murmuring, the results were as follows. 1. Delirious speech and Fading murmuring are given at the speech impediment. Derious speech to be out of language's order and slur the end of his words, and Fading murmuring is to repeat in losing conscious. 2. In constrast with Delirious speech and Fading murmuring, Maniac speech is induced by a general term for manic-depressive psychosis. Luoyan is to say in a feeble voice and mumble in a sleeping condition, and Paraphasia and Solioquy are appeared in a clear mental condition. The speech impediment is caused by damages of the nervous system and speech organ, and Yuyancuoluan is appeared in a feverless condition. 3. The symptoms of Delirious speech are to utter ravings and have a loud and heavy voice, and these resemble the delirium which specially has a speech impediment and muddle in the western medical world. The symptoms of Fading murmuring are to speak ambigously, repeatedly, and illogically and so are similar to the Wernicke dysphasia which is caused by a incomprehensible conversation. 4. The causes of Delirious speech are to spread a stomach heat and the lungs pathogenic qi into heart, not to sweat in cold damage, the Three Yang Combination of syndrome, stomach repletion, yang collapse due to excessive sweat, diarrhea, after diarrhea, heat to enter the blood chamer, feces to remain in the stomach, stasis blood to enter the viscera, to carry anger to extremity, and to be constipated. the cause of Fading murmuring is to despair vacuity desertion of vital essence and energy after a serious illness. 5. The causes of delirium are general infection, postoperative states, and metabolism disorders and those of Wernicke dysphasia are disorders of the blood vessel, brain tumors and traumas. 6. Delirious speech is cured with the discrimination of vacuity and repletion. Baitong Tang(白通湯), Chaihu Guizhi Tang(柴胡桂枝湯), Chaihu Jia Longgu Muli Tang(柴胡加龍骨牡蠣湯) are prescribed in case of vacuity, while Chengqi Tang(承氣湯), Baihu Tang(白虎湯), Liangge San(凉膈散) are in case of repletion. Fading murmuring is treated with Xiao Chaihu Tang(小柴胡湯), Fuzi Tang Jiawei(附子湯加味), Shengmai San(生脈散), and Renshen Sanbai Tang(人蔘三白湯). 7. To acupunture Qimen-Xue(期門穴) is required when it is late to prescribe a medical decoction or the hyperactive liver qi attacking the spleen.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.211-217
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• 1984

To study affinity of proteolytic enzymes to soy proteins, the physicochemical and functional properties of enzymatically modified protein products, kinetic parameters and degree of hydrolysis were measured using trypsin, alcalase (serine type protease) and pronase. Bacterial alcalase and pronase showed much greater affinity to soy protein than animal intestinal trypsin. This effect was very significant when unheated soy isolate was used as a substrate. Specific activities of these enzymes decreased with the increment of substrate concentration (over 2.0%, w/v) when heat denatured soy protein was used as a substrate. However, the decrease in specific activity was negligible at substrate concentrations lower than 2.0%. Polyacrylamide gel electrophoretic results showed that the pattern of 2S protein band changed distinctly in alcalase hydrolysis as compared with those of trypsin and pronase. Protein solubilities of alcalase and pronase hydrolyzates increased by 25-30%, at their pI (pH 5.0) over the control. Virtually no change was observed in solubility by trypsin hydrolysis. Heat coagulability and calcium-tolerance of the protein increased by enzymatic hydrolysis. No clear tendency, however, was observed for emulsion properties, foam expansion and the amount of free -SH groups. The enzyme treatment considerably decreased foam stability.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.26-49
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• 2018

The purpose of this study was to verify the reliability of the solar radiation model and discuss its applicability to the urban area of Seoul for summer heat stress mitigation. We extended the study area closer to the city scale and enhanced the spatial resolution sufficiently to determine pedestrian-level urban radiance. The domain was a $4km^2$ residential area with high-rise building sites. Radiance modelling (SOLWEIG) was performed with LiDAR (Light Detection and Ranging)-based detailed geomorphological land cover shape. The radiance model was evaluated using surface energy balance (SEB) observations. The model showed the highest accuracy on a clear day in summer. When the mean radiation temperature (MRT) was simulated, the highest value was for a low-rise building area and road surface with a low shadow effect. On the other hand, for high-rise buildings and vegetated areas, the effect of shadows was large and showed a relatively low value of mean radiation temperature. The method proposed in this study exhibits high reliability for the management of heat stress in urban areas at pedestrian height. It is applicable for many urban micro-climate management functions related to natural and artificial urban settings; for example, when a new urban infrastructure is planned.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.154-167
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• 2019

As urban heat environment problems occur due to climate change, urban thermal environmental problems such as heat waves and tropical nights are becoming more serious in cities. In South Korea, forest areas favorable for generating cold air account for about 63 percent of the land area. Furthermore, the Jeongmaek, the axis of the main mountain ranges of Korea, is located close to the cities. Hence, the management of cold air is an effective way to improve the thermal environment of Korean cities. We selected the Nak-nam Jeongmaek located in the southern part of Korean Peninsular as well as two cities (Jinju-si and Sancheong-gun) located at the Jeongmaek to analyze its cold air characteristics and suggest management strategies of cold air. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. As a result, the cold air flow generated in the Jeongmaek became clear and the height of cold air layer increased with time. Based on the results, we proposed management plans to maintain and expand the cold air flow. For example, forest areas with active cold air generation were designated as 'cold air conservation areas', and areas requiring management for good cold air flow were as 'cold air management areas'. This study is expected to be useful for establishing systematic urban ventilation plan to improve thermal environment in Korea cities.

• Korean Journal of Environment and Ecology
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• v.33 no.3
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• pp.366-374
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• 2019

This study aims to analyze the characteristics of ventilation corridor and propose its utilization strategies in Jeonju city in order to discuss how to utilize urban ventilation corridors as a planning factor for reducing heat wave impact and fine particle pollution. For these purposes, cold air characteristics such as cold air flow and height of cold air in Jeonju area located in the Honam Jeongmaek were analyzed and major ventilation corridors were specified. Based on them, we proposed mountain management strategies for securing and utilizing ventilation corridors. We used KALM (Kaltluftabflussmodell), a cold air simulation model developed in Germany and identified both the cold air flow and the height of cold air layer generated during 6 hours at night. As a result, the cold air flow generated in the forests located in the northeast and east sides of the Jeonju city became clear and the height of cold air layer increased in the valley terrain and farmland areas with time. In particular, Jeonju City has an ideal structure of urban ventilation corridor. Based on the results, the area where the cold air generation is active was designated as the 'cold air conservation area', and the area requiring the management for the good cold air flow was as the 'cold air management area'. This study is expected to be used as basic data of policy making and research for reducing heat wave impact and fine particle pollution such as climate change adaptation policy and urban forest plans for ventilation corridor composition.

• Korean Journal of Poultry Science
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• v.51 no.2
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• pp.73-82
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• 2024

The gut microbiome of broilers is a critical factor in overall health and productivity. However, high summer temperatures and high stocking density (conventional farm condition) may cause stress to broilers, resulting in an imbalance in the gut microbiome. This study was conducted to compare the gut microbiome of broilers between spring and summer in welfare (Bosung, Jeollanam-do, South Korea) and conventional farms (Jangsu, Jeollabuk-do, South Korea). A total of 31 broilers were assigned to the following groups: conventional farm in spring (n = 8); conventional farm in summer (n = 8); welfare farm in spring (n = 7); welfare farm in summer (n = 8). Cecal digesta were collected from eight broilers from each farm, and microbiome analysis was performed using 16S rRNA gene sequencing. Beta diversity analysis indicated clear differences in cecal microbiome composition between spring and summerin both welfare and conventional farm. At the phylum level, analysis of conventional farm revealed a higher proportion of Bacteroidetes in spring than in summer. At the genus level, broilers exhibited a higher abundance of Bacteroides and Alistipesin spring compared to summer. In contrast, the difference in microbial flora composition observed in welfare farm was relatively small compared to conventional farm. In conclusion, the results of this study suggest that heat stress can negatively affect the caecum microbiome of broilers. However, improvements in the housing environment can mitigate the effects of heat stress.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.4
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• pp.191-203
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• 2013

Purpose: This review is to figure out evidence that suggest effectiveness of Korean Medicine treatments against cervical dysplasia. Methods: Studies on cervical cancer and cervical dysplasia were searched through 6 databases: Korean Studies Information Service System(KISS), National Discovery for Science Leaders (NDSL), Korea Institute of Science and Technology Information (Korean TK), Oriental Medicine Advanced Searching Integrated System (OASIS), the Journal of Korean Medicine, and the Journal of Korean Obstetrics & Gynecology. After that, the articles were extracted with reference point of Korean Traditional Medicine. Results: 37 articles were included lastly according to selection criteria. 3 of them were case reports on cervical dysplasia, and 34 were in-vitro studies on Human Papilloma Virus (HPV) positive cancer cell. In case reports, acupuncture, moxibustion, medical herbs and pharmacoacupuncture were used for treatments of cervical dysplasia with about 3 months. Experimental studies on cervical cancer cell showed that several herbs function with clear heat, eliminate stasis (淸熱解毒, 化瘀消腫) have anti-cancer effects inducing apoptosis. Conclusions: The results of articles are not enough to use in practice. Therefore, we indicates more advanced research methodology as follows: development of Korean Medicine treatment protocol with oral and external, in-vivo experimental study, and evaluation immunity index.