• Nuclear Engineering and Technology
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• 제53권3호
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• pp.833-841
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• 2021

During the postulated severe accident of nuclear reactor, eutectic reaction leads to low-temperature melting of fuel cladding and early failure of core structure. In order to model eutectic melting with the moving particle semi-implicit (MPS) method, the eutectic reaction model is developed to simulate the eutectic reaction phenomenon. The coupling of mass diffusion and phase diagram is applied to calculate the eutectic reaction with the uniform temperature. A heat transfer formula is proposed based on the phase diagram to handle the heat release or absorption during the process of eutectic reaction, and it can combine with mass diffusion and phase diagram to describe the eutectic reaction with temperature variation. The heat transfer formula is verified by the one-dimensional melting simulations and the predicted interface position agrees well with the theoretical solution. In order to verify the eutectic reaction models, the eutectic reaction of uranium and iron in two semi-infinite domains is simulated, and the profile of solid thickness decrease over time follows the parabolic law. The modified MPS method is applied to calculate Transient Reactor Test Facility (TREAT) experiment, the penetration rate in the simulations are agreeable with the experiment results. In addition, a hypothetical case based on the TREAT experiment is also conducted to validate the eutectic reaction with temperature variation, the results present continuity with the simulations of TREAT experiment. Thus the improved method is proved to be capable of simulating the eutectic reaction in the severe accident.

• 대한한의학방제학회지
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• 제24권1호
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• pp.31-43
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• 2016

Objectives Based on related literature, cold and heat, deficiency and excess, true and false, and actually used formulas, paradoxical treatments presented in the 『Plain Questions of Inner Canon of Yellow Emperor』 including ‘treating pseudo-heat symptoms and real cold syndrome with cold herbs, treating pseudo-heat symptoms and real cold syndrome with cold herbs’ were analyzed.Methods Out of literature, paradoxical treatment related classics and papers were investigated and analyzed. Among diseases and syndromes, real cold syndrome with pseudo-heat symptoms, real heat syndrome with pseudo-cold symptoms, real deficiency syndrome with pseudo-excess symptoms, and real excess syndrome with pseudo-deficiency symptoms were reviewed. Among formulas, typical examples of the above mentioned paradoxical treatments were used as examples to analyze paradoxical treatments.Results Treating pseudo-heat symptoms and real cold syndrome with cold herbs is a method that uses herbs with cool and cold nature to treat real cold syndrome with pseudo-heat symptoms and Tongmaeksayeokgajeodamjeuptang is suitable for this method. Treating pseudo-cold symptoms and real heat syndrome with hot herbs is a method that uses herbs with warm and hot nature to treat real heat syndrome with pseudo-cold symptoms and Baekhogainsamtang is suitable for this method.Conclusions Based on the related literature, cold and heat, deficiency and excess, true and false, and actually used formulas examined as mentioned above, the paradoxical treatments presented in the 『Plain Questions of Inner Canon of Yellow Emperor』 are thought to be reasonable paradoxical treatments that fit the diseases and syndromes that actually appeared in our bodies.

• Nuclear Engineering and Technology
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• 제42권1호
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• pp.65-72
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• 2010

The Monte Carlo method for solving heat conduction problems [1-3] is extended for non-constant temperature boundary conditions in this study. The new method can treat problems with any given non-constant boundary temperatures, including heat convection problems with non-constant fluid bulk temperature. A set of problems, particularly the heat transfer problem in a pebble fuel, is analyzed by this new method. In addition, a new method to reduce the statistical errors in kernel fuel regions is introduced when the Monte Carlo method is applied to a pebble fuel.

• Nuclear Engineering and Technology
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• 제39권3호
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• pp.207-214
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• 2007

A new Monte Carlo method for solving heat conduction problems is developed in this study. Differing from other Monte Carlo methods, it is a transport approximation to the heat diffusion process. The method is meshless and thus can treat problems with complicated geometry easily. To minimize the boundary effect, a scaling factor is introduced and its effect is analyzed. A set of problems, particularly the heat transfer in the fuel sphere of PBMR, is calculated by this method and the solutions are compared with those of an analytical approach.

• 한국주조공학회지
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• 제13권4호
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• pp.323-332
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• 1993

An implicit finite difference formulation with three methods of latent heat treatment, such as equivalent specific heat method, temperature recovery method and enthalpy method, was applied to solidification analysis. The Neumann problem was solved to compare the numerical results with the exact solution. The implicit solutions with the equivalent specific heat method and the temperature recovery method were comparatively consistent with the Neumann exact solution for smaller time steps, but its error increased with increasing time step, especially in predicting the solidification beginning time. Although the computing time to solve energy equation using temperature recovery method was shorter than using enthalpy method, the method of releasing latent heat is not realistic and causes error. The implicit formulation of phase change problem requires enthalpy method to treat the release of latent heat reasonably. We have modified the enthalpy formulation in such a way that the enthalpy gradient term is not needed, and as a result of this modification, the computation stability and the computing time were improved.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년도 춘계 학술대회 개요집
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• pp.146-147
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• 2006

In order to prevent the environmental pollution, the dryers are commonly used to treat sludge that one of sewages is polluting the quality of water. Rotary dryer is a good apparatus to treat them. The rotary dryer is the way that is to make substance transmission and heat using hot air between sludge particle and heated gas. In this paper, a numerical analysis was performed for the structural analysis of the 3-pass rotary dryer through the finite elemeny method and an experiment was done for the structural stability. And reasonable relation was found between analysis and experiment.

• 대한한의학회지
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• 제41권3호
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• pp.81-97
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• 2020

Objectives: The objective of this study is to review the methods of combining acupoints of HANGYEOK(Cooling Mode) and YEOLGYEOK(Heating Mode) in Saam Acupuncture Method. Methods: We searched and investigated the journals and literatures by OASIS(Korea Institute of Oriental Medicine) and relevant searching engines with the key word "Saam, Hangyeok, Yeolgyeok". Unfortunately there was no relevant articles on this theme except six literatures. Six literatures with the key words relevant to Saam and acupuncture were selected and analyzed according to each composition of acupuncture prescription especially focusing on HANGYEOK and YEOLGYEOK. Results: Analyzing HANGYEOK and YEOLGYEOK of 12 meridians, two different methods emerged. In HANGYEOK to treat Heat Pattern, one method is to tonify Water points and directly sedate Fire points. The other is also to tonify Water point, but sedate Earth points instead of Fire points. It is assumed that Earth sedation method is to eradicate the underlying Fire. In only Heart meridian and Pericardium meridian there is one method to treat Heat Pattern: Water tonification and Fire Sedation. In YEOLGYEOK to treat Cold Pattern, there is one method to tonify Fire points and sedate Water points. In Pericardium meridian and Triple Energizer meridian there are some different combination of acupoints depending on literatures. Conclusions: Considering HANGYEOK and YEOLGYEOK in Saam Acupuncture Method, two methods are mainly discussed in HANGYEOK; Water Tonification Fire Sedation and Water Tonification Earth Sedation. To remove the underlying Fire, it is regarded that Water Tonification Earth Sedation is appropriate and close to Saam's thought.

• 한국한의학연구원논문집
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• 제2권1호
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• pp.454-484
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• 1996

There are many factors to evoke pain, for example cold, heat, seven emotion, digestion, fatigue, venemous worms, deficiency of blood etc., and its pathogenesis is complicated. Treatments for pain in oriental medicine are as follows. 1. Pharmacotherapy is a method to treat pain by different effects of herbal medicine, for example, regulating vital energy, activating blood circulation, eliminating phlegm, and dispelling the cold evil etc. 2. Acupuncture and moxibustion therapy is a kind of external application, it has a distinct effect in relieving pain. Recently its operation method has been more developed, so new acupuncture therapies are used in clinics. There are electroacupuncture, auricular acupuncture and injection of drugs at an acupuncture points etc. 3. Oriental physiotherapy is a treatment method to stimulate acupuncture points and meridians. (1) Hot pack, Paraffin bath, Microwave, Ultrasound, Short wave, Infra-red etc. are used to treat cold syndrome by dispersing cold by warming the channels. (2) E.S.T., I.C.T., T.E.N.S., S.S.P., cupping treatment etc. are used to treat disorders of vital energy. (3) Health ion, Carbon, T.D.P., etc are used to treat conic and deficiency syndrome.

• 동력기계공학회지
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• 제10권2호
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• pp.36-40
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• 2006

In order to prevent the environmental pollution, the dryers are commonly used to treat sludge that one of sewages is polluting the quality of water. Generally, the drying method is various as to the property of material and use. Rotary dryer is a good apparatus to treat them. It is the way that is to make substance transmission and heat using hot air between sludge particle and heated gas. In this paper, we developed a 3-pass rotary dryer for a design program for the 3-pass rotary dryer with various conditions. The working conditions of dryer are a raw sludge feed rate, input & output water content and operation time etc.

• 대한한의학방제학회지
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• 제27권1호
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• pp.65-71
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• 2019

Objective : This study aims to diversify interpretation of formulas from "Onbyungjobyun" by analyzing various formulas from "Onbyungjobyun" as basic formulas. Method : This study found herbal communities of combination by analyzing herbal combinations based on network analysis of formulas from "Onbyungjobyun", and has analyzed each community of combination as basic formulas. Result : The results of network analysis showed a total of 3 herbal communities of combination; first was medicinal herbs from Eungyo-san(銀翹散), Jeungaek-tang(增液湯), Bokmaek-tang(復脈湯), Gyeji-tang(桂枝湯), Sogeonjung-tang (小建中湯) series; second was medicinal herbs from Angungwoohwang-hwan(安宮牛黃丸); third was medicinal herbs from Baekho-tang(白虎湯), Jaseol-dan(紫雪丹), Sayeok-tang(四逆湯) series. Conclusion : The formulas from "Onbyungjobyun" are consisted of herbal communities of combination; that treat warm-heat pathogen and supplies yin essence or yang qi; treat reverse transmission to the pericardium(逆傳心包); and treat heat in the qi phase in Onbyeong and cold-dampness in the middle energizer.