• 한국안전학회지
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• 제31권4호
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• pp.55-63
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• 2016

A dust explosion is a phenomenon of strong blast wave propagation involving destruction which results from dust pyrolysis and rapid oxidation in a confined space. There has been some research done to find individual explosion characteristics and common physical laws for various dust types. However, there has been insufficient number of studies related to the heat of combustion of materials and the oxygen consumption energy about materials in respect of dust explosion characteristics. The present study focuses on the relationship between dust explosion characteristics of wood dust samples and oxygen consumption energy. Since it is difficult to estimate the weight of suspended dust participating in explosions in dust explosion and mixtures are in fuel-rich conditions concentrations with equivalent ratios exceeding 1, methods for estimating explosion overpressure by applying oxygen consumption energy based on unit volume air at standard atmospheric pressure and temperature are proposed. In this study an oxygen consumption energy model for dust explosion is developed, and by applying this model to TNT equivalent model, initial explosion efficiency was calculated by comparing the results of standardized dust explosion experiments.

• 기술사
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• 제5권19호
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• pp.3-16
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• 1972

1. Purposes and importances of the study. In gaining heating resources by combustion of briquette, which is the necessaries of every day's life, victims occur from poisonous affection of combustion gas (carbon mono-oxide) in every year and this gas attributable to increase death rate proportion to the high demand of briquette usage. It arise great problem ill point of national sanitation. Therefore, the study has a big aim to accomplish depressing CO gas or stimulating comlete combustion by both the methods of physical improvement of present combustion devices and chemical improvement by using V$_2$O$\sub$5/ catalyst to depress CO gas or fasten complete combustion Progress. Sucessful result of this study will not only to decrease the death rate but also to contribute fearless handling of briquette combustion so as to perform improving public Welfare. 2. Contents and scope of study. A. comparison of present and improved fuel hole device. B. Examination of effectness of improved elements. C. Effectness of miffed usage of catalyst. D. Comparison of Catalyst effectness. E. Examination of effectness of black slate containing V$_2$O$\sub$5/. 3. Results and recommendations of the study A. Absolute necessity of supplying secondary air by improved combustion device. B. Oxide Vanadium (V$_2$O$\sub$5/) has the greatest effectness to eliminate CO gas. C. Most effective catalyst of V$_2$O$\sub$5/ containing slate comes from "Samgoe" coal mine. D. By plastering catalyst on the cover plate of fire hole, it stimulate chemical reaction of re-combustion and preserving heat. E. Recommend to continute further precise study to practice with low-cost and handy devices to be applied the study results.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.745-748
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• 2008

과거 건설 구조물은 사용 하중을 견딜만한 성능과 사용성, 부식에 대한 저항성 정도만이 요구되었다. 그러나 9.11 사건 이후 이러한 관점은 바뀌어, 폭발에 의한 충격 하중 및 그와 동시에 발생할 수있는 화재로 인한 열에 견딜 수 있는 구조물의 저항 성능이 기본적인 요구 조건으로써 중요시되고있다. 전 세계가 연일 테러의 위협 아래 놓여있는 현 시점에서 구조물의 내폭 성능은 매우 중요한 부분이라 할 수 있다. 이에 본 연구에서는 기존의 건설 재료로써 폭넓게 사용되고 있는 시멘트 복합체 혹은 콘크리트에인장 강도 및 연성이 뛰어난 FRP composite을 결합시켜 내폭 성능이 우수하고 기존 구조물 및 신설구조물에 모두 시공이 가능한 최적화된 분절 복합체(Segmented Composite) 및 층 구조(Layered Structure)를 개발하고, 그 성능을 평가하고자 한다. 이러한 내폭 성능의 향상을 통해, 열과 충격 하중, 동하중 및 high strain에 의한 구조물의 붕괴를 줄이고 붕괴 시점을 보다 늦출 수 있다면, 이로인해 발생되는 인명 피해 및 경제적 손실을 최소화시킬 수 있을 것이다.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년 춘계학술발표대회 논문집
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• pp.278-283
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• 2009

This study aims to figure out the old people's needs for modification of their housing to maintain an independent lifestyle despite their health status and living arrangements. The total of 438 residents take part in the questionnaire survey research through the quota sampling method grouped by age (60-64 group, 65-69 group, 70-74 group, and over 75 group), sex (male and female), and house type (apartment houses and others). The results are as follows. (1) The old people's most inspired modification needs in interior spaces are remodeling the heating controls in the living room and the bedroom, ventilation facilities and storage spaces in the kitchen, non-slip tile flooring and ventilation facilities in bathroom, an easy door-lock, non-slip tile flooring, a draft cut-off, and storage spaces in the entrance. Besides they require emergency alarm, easy door and window locks, fire and gas alarm, and furniture with easy handling. It is necessary to supply the aged with the appropriate heating controls for their sensitivity to heat, with enough storage spaces for the increased possessions, and with diverse safety systems reflected blunting of mobility and sensibility. (2) As they grow older, the aged require more remote controls and safety facilities such as emergency alarm, easy locks and furniture with distinguishable colors. Male elderly is more concerned with safety, while female elderly do with convenience due to their different time spending in the house. The elderly residents in the apartment houses require the heating controls, a draft cut-off, and storage space less than other types of houses. Thus modification of the heating controls, a draft cut-off, and storage space are regards as basic needs for the elderly residents in non-apartment houses.

• 한국수소및신에너지학회논문집
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• 제23권1호
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• pp.73-82
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• 2012

A 2-dimensional heterogeneous reactor model was developed and simulated for a tube reactor of packed bed where the steam-$CO_2$ combined reforming reaction of natural gas proceeded to produce synthesis gas. Under the reactor feeding rate, 45 $Nm^3$/h, of the reactant gas stream, the 2-dimensional heterogeneous reactor model showed the similar results to those from the ASPEN simulator although there were some discrepancies between the two in the temperature and the $H_2$/CO ratio of the reformed gas at the reactor exit. The calculated enthalpy difference between the reformed gas at the reactor exit and the reactant gas fed to the reactor was closely correspondent to the total amount of heat transferred to the reactor interior from the furnace. This supports that the 2-dimensional heterogeneous reactor model was reasonably established and the numerical solution was properly obtained.

• 대한한의학방제학회지
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• 제17권1호
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• pp.61-74
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• 2009

This report describes 46 studies related to prescriptions which are mainly used Semen Arecae from Dongeuibogam. The following conclusions were reached through investigations on the prescriptions that use Semen Arecae as a main component. 19.6% of a malaria, 17.4% of an evacuation problem, recorded the largest number of clinical frequency of the prescriptions in therapeutic use when Semen Arecae was taken as a main component in prescriptions Prescriptions that utilize Semen Arecae as the main ingredient are used in the treatment of a malaria, an evacuation problem and a malignant dermatosis. they are also used for treating 11 different types of diseases. The prescriptions are compounded with Semen Arecae as a main component which can be applied to an affection by wind-cold, a heat(fire) syndrome, a cold-stroke, a phlegm-retention syndrome, a constipation induced by apoplexy, a stagnation of vital energy, an asthenia of the spleen and the stomach, a convulsion caused by improper diet, a parasitic infestation and a traumatic disease. The dosage of Semen Arecae is 2.5pun(nearly 0.94g) to 3don(nearly 11.25g), however 1don(nearly 3.75g) has been taken the most for clinical application. When Semen Arecae is combined with basic prescriptions such as Ijintang and Bulium, it applies symptoms of malaria. In addition, when Semen Arecae is combined with basic prescriptions such as Daemainhwan, Soseungkitang and Samatang, it utilizes an evacuation problem.

• 동의생리병리학회지
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• 제23권5호
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• pp.964-968
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• 2009

The purpose of this study is to select the major pulse indicators and evaluate their significance in discriminating the subtypes of Pattern Identifications (PI) from stroke patients. Decision tree analysis was carried out using clinical data collected from 835 stroke patients with the same subtypes diagnosed identically by two experts with more than 3 year clinical experiences. Among the 10 pulse indicators, 6 major pulse indicators (slow, rapid, strong, weak, slippery, and fine pulse) were selected by decision tree analysis. The accumulated distributions of six pulse indicators in each PI showed that strong was major pulse indicator in Fire-Heat pattern, slippery in Dampness Phlegm pattern, weak in Qi Deficiency pattern. But there were two major combinations in Yin deficiency pattern, weak or fine with rapid pulse and weak or fine without rapid pulse. Therefore, it is suggested that 6 pulse indicators can be used for discrimination of PI in stroke patients, though the combination studies between these pulse indicators and the other PI indicators are left for further study.

• 한국태양에너지학회 논문집
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• 제36권5호
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• pp.73-89
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• 2016

To assure maximum economic benefits and the energy performance of solar water heating systems, the proper sizing of components and operating conditions need to be optimized. In recent years, a number of studies to design optimally solar water heating systems have been tried. This paper presents a design method for optimizing the various capacity-related and installation-related design variables based on life cycle cost using a genetic algorithm. The design variables considered in this study included the types and numbers of solar collector and auxiliary heaters; the types of storage tanks and heat exchangers; the solar collector slope; mass flow rates of the fluid on the hot and cold sides. The suggested method was applied for optimizing a solar water heating system for an elementary school in Seoul, South Korea. In addition, the effectiveness of the proposed optimization method was assessed by analyzing the obtained optimal solutions of six case studies, each of which was simulated with different solar fractions. It is observed that a trade-off between the equipment cost and the energy cost results in an optimal design that yields the lowest life cycle cost. Therefore, it could be helpful to apply the optimal solar water heating system by comparing the various design solutions obtained by using the optimization method instead of the engineer's experience and intuition.

• 대한한의학방제학회지
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• 제11권1호
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• pp.45-55
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• 2003

From the study of the symptom, pathology in prescription of Ha-Tong from The Bangyakhapeun. I have reserched 163 prescription. It can be concluded as follows. 1. Prescription about Fecal disease which was the most as 11.66% of the whole, following order Internal disease(6.75%), Uterus Disease(5.52%) Sick-by-Cold Disease(5.52%), Eye Disease(4.91%), Blood Disease(4.91%), Unbalanced humoral status Disease(4.91%), Gynecologic Disease(4.91%). 2. The Fecal Disease divide diarrhea and dysentery; The Internal Disease divides with Sik-sang(食傷) Chu-sang(酒傷), Sik-juck-yu-sang-han(食積類傷寒), Carbonic acid, Vomiting acid; The Uterus Disease divides with Urinnary Disadvantage, Urinary retention, Incontinence; The Sick-by-Cold Disease divides with yang-myung-byung(陽明病), sang-han-goi-jng(傷寒壞證), sang-han-bun-gal(傷寒煩渴), sang-han-sum-ou, sang-han-hyul-jng(傷寒血證), sang-han-ja-ri(傷寒自利), sang-han-bun-jo-jng(傷寒煩燥證). 3. The Diarrhea and Dysentery many used o-ryung-san, hwng-gum-jak-yak-tang(黃芩芍藥湯) hyang-ryun-hwan(香連丸) etc, and The Internal Disease many used pyung-we-san(平胃散) as a basic prescripton. 4. The organ problem use the Sil-yuol(實熱) of the liver, stomach, lung, uterus, small intestine; six natural factors problem used the Sil-jng(實證) of the wind, fire, heat, cold, dampness; And used Unbalanced humoral status, lntrnal hurt, qi and blood, seven extream feeling.

• 대한한의학방제학회지
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• 제26권2호
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• pp.147-170
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• 2018

Objectivs : This report describes the studies as follows through the research of 163prescribtions in low-chapter from Bangyakhappyun. Methods : Analysis the 163prescribtions of basic prescribtions, therapeutic area, symptoms and pathology. Result : Many prescriptions are contained in the diseases areas such as defecate diseases, women diseases, internal diseases, exogenous febrile diseases. And prescriptions in the low-chapter are used in the areas such as eye, aggregation, mouth and tongue, teeth, hand, back, neck, emergency. Eighty-five basic prescriptions are analyzed from the low-chapter and the ratio of nineteen prescriptions containing Ijintang, Pyeongwisan, Oryungsan, Samultang, Sunggitang, Jichultang are over 60%. The efficacy classifications containing basic prescriptions frequently used are researched in the following order: heat-clearing and fire-purging formulae, digestant formulae, phlegm-dispelling formulae, qi-regulating formulae and blood-activating formulae. And tonifying and replenishing formulae are rarely used. Most of the prescriptions in the low-chapter are used for the excess syndrome and few of them are used for the deficiency syndrome. And six excesses, food damage, phlegm are the major causes of excess syndrome. Conclusions : As s result of study on analysis all prescriptions in low-chapter from Bangyakhappyun. We can understand more about basic prescriptions, symptoms of prescriptions and pathology.