• Title/Summary/Keyword: Cold and Heat

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Evaluation on Thermal Performance of Thermosyphon by Numerical Analysis (열사이펀의 열성능 산정을 위한 수치해석 연구)

  • Jang, Changkyu;Choi, Changho;Lee, Jangguen;Lee, Chulho
    • Journal of the Korean Geotechnical Society
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    • v.30 no.9
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    • pp.57-66
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    • 2014
  • The ground in cold region consists of active and permafrost layers. The active layer at the unstable state may cause ground corrosion and uplift, when the temperature of frozen ground increases due to seasonal changes. The thermosyphon is one of the stabilization methods to maintain the ground stability in the frozen ground. The thermosyphon is a closed two-phase convection device that extracts heat from the ground and discharges it into the atmosphere. In this study, ground freezing experiment using a thermosyphon and simulated ground with the isolation material was conducted to evaluate the thermal performance of the thermosyphon. In order to consider the thermal performance of the thermosyphon, commercial numerical program (TEMP/W) was adopted. Likewise, the thermal performance of thermosyphon and thermal properties of ground were applied in the numerical model. In a series of comparisons with experiment results and numerical study, thermal performance of thermosyphon can be evaluated.

Production of Fibrinolytic Enzyme and Peptides from Alkaline Fermentation of Soybean Curd Residue by Bacillus firmus NA-1 (Bacillus firmus NA-1 균주를 이용한 비지로부터 혈전분해능효소 및 펩타이드 생산)

  • Oh, Soo-Myung;Seo, Ji-Hyun;Lee, Sam-Pin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.6
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    • pp.904-909
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    • 2005
  • To produce functional food ingredient from the soybean curd residue (SCR), alkaline fermentation was performed with SCR from cold processed (D-SCR) or hot processed (P-SCR) tofu. The solid- state fermentation was performed by Bacillus firmus NA-1 at $42^{\circ}C$. The fermentation of heat-treated D- SCR resulted in higher production of peptides and fibrinolytic enzyme compared with D-SCR without heating. The P-SCR showed higher production of peptides, fibrinolytic enzyme, indicating alkaline pH after fermentation for 18 hr. When the moisture content of P-SCR was reduced to $60\%$, the production of peptides and fibrinolytic enzyme were enhanced. The P-SCR fortified with $10\%$ MFS (micronized full-fat soy flour) showed higher fibrinolytic enzyme activity and consistency index by fermentation of Bacillus firmus NA-1 Furthermore, the P- SCR fortified with $20\%$ MFS indicated relatively higher peptide content, fibrinolytic enzyme activity and enhanced flavor. By increasing the addition of MFS, the peptide content of fermented P-SCR was increased significantly, but fibrinolytic enzyme was slightly decreased.

A study of Literature review on the retaining needle (유침(留針)에 관한 문헌적(文獻的) 고찰(考察))

  • Park, Chun-ha;Kim, Jae-hong;Wu, Tung-sun;Park, Eun-ju;Shin, Jung-chul;Han, Sang-gyun;Yun, Yeu-chung;Cho, Myung-rae
    • Journal of Acupuncture Research
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    • v.20 no.1
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    • pp.85-96
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    • 2003
  • Objectives : We were studied the retaining needle to offer basic materials for the study of it. methods: To study the retaining needle, we were reviewed the ancient, the present text and the thesis. Results: 1. There are many ways form general acupuncture technique to needle-embedding therapy by the spending time of the retaining needle. 2. The method retaining needle is divided into Active method of the retaining needle(動留針法) and Passive methoid of the retaining needle(靜留針法) by the existence of Qi-promoting. 3. In case of Deficiency Syndrome, protracted discase, dolorific disorder, convulsive disorder, and Cold Syndrome, the spending time of the retaining needle takes longer, in case of Heat Syndrome and exterior Syndrome, the spending time of the retaining needle takes shorter. 4. In case of acute disease and attack of chronic disease, we can use Active methoid of the retaining needle(動留鍼法) with retaining needle for a long time, in case of chronic disease, we can use Passive methoid of the retaining needle(靜留針法). 5. In case of Young people, a man in the prime of life, and a people who can stand the stimulation of needle, we can make the spending time of the retaining needle be longer and use Active methoid of the retaining needle(動留針法), but in case of a baby and a weak people, we had better shorten the spending time of the retaining needle or not do it. 6. The spending time of the retaining needle must be shorter in spring and summer, must be longer in fall and winter. 7. The spending time of the retaining needle is various by acupuncture point. 8. When the spending time of the retaining needle is too longer, we can injure Vital-qi of a patient, otherwise in opposite situation, Pathogenic is stagnated so pathogenic stage is repeated.

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Manufacture of Dropwort Extract Using Brown Sugar, Fructose Syrup and Oligosaccharides (흑설탕, 과당, 올리고당을 이용한 미나리 추출물의 제품화)

  • Son, Min-Jung;Cha, Chun-Geun;Park, Jung-Hyun;Kim, Chan-Shick;Lee, Sam-Pin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.9
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    • pp.1485-1489
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    • 2005
  • The dropwort was fermented by steeping with brown sugar, fructose syrup or oligosaccharide at room temperature for 2 month, and then stored at cold room for 6 months. The dropwort extracts prepared with three different sugars showed more than $50^{\circ}$Brix, below pH 4.0 and about $0.7\%$ titratable acidity. The dropwort extract with brown sugar showed $1.6{\times}10^6$ viable cell counts and $21.2\%$ reducing sugar. Formation of $CO_2$ gas was superior to the dropwort fermented with brown sugar or oligosaccharide. The dropwort extract with fructose syrup indicated $9.0{\times}10^3$ viable cell counts and $50.1\%$ reducing sugar. Microorganism present in fermented dropwort extract was effectively pasteurized by the addition of $3\%$ citric acid and heat-treatment at $85^{\circ}C$ for 15 min, resulting in the less production of $CO_2$ gas. The dropwort extracts prepared with brownsugar, fructose syrup or oligosaccharide was suitable for the standardization that required for plant extract in Korea Food Codex.

Acidic and steaming treatments of tteokbokki rice cake to improve its microbial and textural properties (떡볶이 떡의 미생물 안전성 및 식감 향상을 위한 유기산과 증숙 처리)

  • Cheon, Hee Soon;Cho, Won-Il;Lee, Su Jin;Chung, Myong-Soo;Choi, Jun-Bong
    • Korean Journal of Food Science and Technology
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    • v.49 no.5
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    • pp.502-506
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    • 2017
  • To improve the storage and firmness of Tteokbokki tteok Korean-style rice cakes with spicy sauce, steaming of the rice dough, soaking of the rice cake in acidic solution, and heat sterilization were conducted sequentially. The untreated control could be stored for 1 month under cold conditions, but this was extended to 10 months at room temperature ($15-30^{\circ}C$) after immersion in lactic acid solution (pH 4.0) for 20 min and heating to $100^{\circ}C$ for 30 min. The mechanical strength, which was related to firmness, was significantly increased to $11.4kgm/s^2$ compared with the untreated rice cakes ($8.8kgm/s^2$, p<0.05) and the overall descriptions of the sensory evaluation, including texture, was significantly higher than the control (p<0.05). The average size of the pores in the treated rice cakes was smaller than that of the conventional sample and the texture was improved as a result of decreased starch elution from smaller pores.

The Clinical Study on Ordinary Symptoms and Pathological Symptoms of Stroke In-patients based on Sasang Constitutional Medicine (중풍입원환자의 체질별 소증(素證)과 중풍 발생 후 병증(病證)에 관한 임상적 연구)

  • Ham, Tong-Il;Hwang, Min-Woo;Lee, Tae-Kyoo;Kim, Sang-Bok;Lee, Soo-Kyung;Koh, Byung-Hee;Song, Il-Byung
    • Journal of Sasang Constitutional Medicine
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    • v.16 no.3
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    • pp.34-45
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    • 2004
  • 1. Objectives The purpose of this study is to investigate constitutional ordinary and pathological symptoms differences among each constitutional groups of stroke in-patients. 2. Methods 101 stroke in-patients(Soyangin(SY) $n^{a)}=52$, Taeumin(TE) n=39, Soeumin(SE) n=10) hospitalized at Kyung-Hee Oriental medical center from Nov. 2003 to Sept. 2004 were investigated through questionnaire which consists of 18 parts, 289 questions(156 questions concerned ordinary symptoms and 133 pathological symptoms). The answers were analyzed statistically in order to find the questions which represent the significant differences among each constitutional groups. ( a) number of patients) 3. Results As for the ordinary symptoms, majority of the Soyangin group replied that they experienced "frequent dreams during sleep" and "scarce constipation". Majority of the Taeumin group affirmed to "dark redness of face", "dry nose", "low intolerance of heat", "good appetite and digestion", and "frequent overeating experiences". Majority of the Soeumin group affirmed to "pale face", "insomnia", "frequent constipation", "poor appetite and digestion", "small amount of diet", "slow eating", "fond of warm or hot water", and "easily tired(especially after sweating)". As for the pathological symptoms, majority of the Taeumin group affirmed to "frequent optic fatigue", "frequent tinnitus", "frequent bitter mouth", "fond of cold water", "flatulent", "stuffiness in the navel area", "irregular stool habits", "frequent constipation", "large amount of sweat", and "frequent rigidity of neck". Majority of the Soeumin group affirmed to "bad appetite", "fond of warm or hot water", "drink small amount of water", "sensitive during sleep" and "frequent heavy head". 4. Conclusions Through this study, We found statistically significant questions distinguishing the characteristics of each constitutional group.

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Operational Properties and Microbial Inactivation Performance of Dielectric Barrier Discharge Plasma Treatment System (유전체장벽방전 플라즈마 장치의 조작특성과 살균력)

  • Mok, Chulkyoon;Lee, Taehoon
    • Food Engineering Progress
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    • v.15 no.4
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    • pp.398-403
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    • 2011
  • A dielectric barrier discharge plasma (DBDP) treatment system was fabricated and the optimum operating conditions for the plasma generation were determined in order to explore the potential of cold plasma as a non-thermal proessing technology. The microbial inactivation performance of the system was also evaluated against Staphyloocus aureus. The system consisted of power supply, transformer, electrode assembly and sample treatment plate. The input power was 220 V single phase AC and amplified to 10.0-50.0 kV on a transformer. A pulsed sine wave of frequency 10.0-50.0 kHz was introduced to the electrode embedded in ceramic as a dielectric barrier material in order to generate plasma at atmospheric pressure. Higher currents and consequently greater power were required for the plasma generation as the frequencies increased. A homogeneous and stable plasma was generated at currents of 1.0-2.0, and frequencies of 32.0-35.3 kHz. The optimum electrode-gaps for the plasma generation were 1.85 mm without loaded samples. More power was consumed as the electrode-gaps increased. The practically optimum electrode- gap was, however, 2.65 mm when samples were treated on slide-glasses for microbial inactivation. The maximum temperature increase after 10 min treatment was less than 20$^{\circ}C$, indicating no microbial inactivation effect by heat and thereby insuring a non-thermal method. The DBDP inactivation effect against Staphyloocus aureus increased linearly with treatment time up to 5 min, but plateaued afterward. More than 5 log reduction was achieved by 10 min treatment at 1.25 A.

Study of the Effects of Ambient Temperature and Car Heater Power on the Train Cabin Temperature (외기 온도와 난방 출력의 철도차량 객실 온도에 대한 영향 연구)

  • Cho, Youngmin;Park, Duck-Shin;Kwon, Soon-Bark;Jung, Woo-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.9
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    • pp.5877-5884
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    • 2014
  • Recently, abnormally cold weather has been reported more frequently in winter due to the climate change and abnormal weather changes. On the other hand, the heating capacity of a railcar may be not enough to warm the cabin under severe cold climatic conditions, which is one of the reasons for the passengers' complaints about heating. In this study, the effects of ambient temperature and heater power on the cabin temperature was investigated to obtain the minimum ambient temperature for the tested railcar. The test railcar was placed in a large-climatic chamber, and various ambient temperature conditions were simulated. The effects of the heater output were investigated by monitoring the cabin temperature under a range of heater output conditions. The mean cabin temperature was $14.0^{\circ}C$, which was far lower than the required minimum temperature of $18^{\circ}C$, under a $-10^{\circ}C$ ambient temperature condition with the maximum heat power. When the ambient temperature was set to $0^{\circ}C$ and $10^{\circ}C$, the maximum achievable cabin temperature was $26.1^{\circ}C$ and $34.0^{\circ}C$. Through calculations using the interpolation method, the minimum ambient temperature to maintain an $18^{\circ}C$ cabin temperature was $-6.7^{\circ}C$ for this car. The vertical temperature difference was higher with a higher power output and higher ambient temperature. The maximum vertical temperature difference was higher than $10^{\circ}C$ in some cases. However, the horizontal temperature difference vs. low temperature (< $2^{\circ}C$) was independent of the power output and ambient temperature. As a result, it is very important to reduce the vertical temperature difference to achieve good heating performance.

An Analysis of Clinical Characteristics on the Medical book of Koryŏ Dynasty, Hyang'yak Kugŭppang (鄕藥救急方, Medical Recipes of Local Botanicals for Emergency Use) (고려 의서 『향약구급방』의 임상 의학 특징 분석)

  • Oh, Chaekun;Kim, Sanghyun;Yi, Kiebok;Jeon, Jongwook;Shin, Dongwon
    • Herbal Formula Science
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    • v.28 no.3
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    • pp.289-300
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    • 2020
  • Objectives : In this paper, We pointed out medico-historical meaning of Hyang'yak Kugŭppang (鄕藥救急方, Medical Recipes of Local Botanicals for Emergency Use), a medical book of Koryŏ Dynasty, breaking from the existing analysis view based on Hyang'yak (鄕藥), local herbs produced in Korean Peninsula. Methods : For that purpose, we analyzed the clinical characteristics of the diseases and symptoms, strategies of treatment, therapeutic tools, drug formulations, composition of herbal formulas in Hyang'yak Kugŭppang. Results : The following characteristics were confirmed in Hyang'yak Kugŭppang. First, it contained a way to cope with the diseases and symptoms that do not have to check the exterior, interior, cold, and heat. Also, it introduced basic strategies such as reducing, facilitating flow, draining downward, warming, or tonifying, etc. It mainly included herbal medicine as the therapeutic tools, and introduced formulas composed by single herb than complex recipes. It suggested external applications more than internal use, and proposed formulations in the form of decoctions or powders, etc. The herbs of formulas were used by experience without explanations of nature & taste, efficacy of each herbs. Conclusions : Hyang'yak Kugŭppang is a book of medical recipes for emergency use that has been distributed to help gentries, even if they do not have professional medical knowledge, to instantly cope with diseases and symptoms with medicines that are easy to obtain. Previous researches has analyzed the value of Hyang'yak Kugŭppang as a collection of information of hyang'yak, and used it as a historical basis of the uniqueness of Korean medicine. Since Hyang'yak Kugŭppang is not a book specialized for herbs, but rather a clinical medical book that introduces recipes for specific symptoms of diseases, if we pay attention to the clinical characteristics of Hyang'yak Kugŭppang, it will provide an opportunity to describe Koryŏ or Korean medicine in a new way.

Effects of Annealing Temperature on Interface Properties for Al/Mild Steel Clad Materials (어닐링 온도 변화가 Al/연강 클래드재의 계면 특성에 미치는 영향)

  • Jeong, Eun-Wook;Kim, Hoi-Bong;Kim, Dong-Yong;Kim, Min-Jung;Cho, Young-Rae
    • Korean Journal of Materials Research
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    • v.22 no.11
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    • pp.591-597
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    • 2012
  • For heat exchanger applications, 2-ply clad materials were fabricated by rolling of aluminum (Al) and mild steel sheets. Effects of annealing temperature on interface properties, especially on inter-layer formation and softening of strain hardened mild-steel, for Al/mild steel clad materials, were investigated. To obtain optimum annealing conditions for the Al/mild steel clad materials, annealing temperature was varied from room temperature to $600^{\circ}C$. At the annealing temperature about $450^{\circ}C$, an inter-layer was formed in an island-shape at the interface of the Al/mild steel clad materials; this island expanded along the interface at higher temperature. By analyzing the X-ray diffraction (XRD) peaks and the energy dispersive X-ray spectroscopy (EDX) results, it was determined that the exact chemical stoichiometry for the inter-layer was that of $Fe_2Al_5$. In some samples, an X-layer was formed between the Al and the inter-layer of $Fe_2Al_5$ at high annealing temperature of around $550^{\circ}C$. The existence of an X-layer enhanced the growth of the inter-layer, which resulted in the delamination of the Al/mild-steel clad materials. Hardness tests were also performed to examine the influence of the annealing temperature on the cold deformability, which is a very important property for the deep drawing process of clad materials. The hardness value of mild steel gradually decreased with increasing annealing temperature. Especially, the value of hardness sharply decreased in the temperature range between $525^{\circ}C$ and $550^{\circ}C$. From these results, we can conclude that the optimum annealing temperature is around $550^{\circ}C$ under condition of there being no X-layer creation.