• Journal of the Korean Society for Heat Treatment
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• v.8 no.2
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• pp.127-136
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• 1995

The simultaneous addition of Al and Cr to the surface of Ni-and Fe-base alloy provides enhanced resistance to oxidation and corrosion in high temperatures. However, because of the large differences in thermodynamic stabilities of the volatile halides of Al and Cr, the codeposition of Al and Cr by halideactivated pack cementation is only possible for very specific, limited combinations of conditions. In this study, the experiments on the combinations of various metallic source powders and activators were conducted in order to obtain codeposition layers of Al and Cr on Ni with adequate composition by pack cementation. When Cr-Al masteralloy was used as a source powder, it was not easy to control Al and Cr content sensitively in the coating layers. On the other hand, when pure Cr and Al powder was used, ${\beta}$-NiAl layer containing about 20wt % Cr was obtained.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.1
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• pp.8-19
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• 2017

This study on "Wenbingtiaobian" covers identifying pattern of prescription, understanding system of multiple syndrome differentiations, characteristics of treatment and medicinal substances. The source books are "Korean translation of Wenbingtiaobian", "Modern Shanghanlun", "Jinkuiyaolueyishi", "Chinese Medicine Formulas". "Wenbingtiaobian" has system of multiple patterns including three energizer syndrome differentiation, classification of disease, six meridian syndrome differentiation and wei-qi-ying-xue syndrome differentiation. That describes cause, location, nature, power and transmutation of disease. Wei-qi-ying-xue pattern is meaningful to warm-heat disease and three energizer pattern is relevant to dampness-heat disease. The warm disease shows mostly yang brightness bowel syndrome and patterns of three yin viscera. In aspect of the heat disease, qi aspect pattern makes up the largest number of syndrome differentiation and have sometimes with bowel excess or fluid deficiency. And treatment for wei aspect pattern is primarily 'outthrust the pathogen with pungent-cool'. Deficiency cold pattern and cold pattern with dampness occupy most of cold patterns. And many dampness patterns are dampness-heat pattern in middle energizer and 'inhibited lung qi transforming' is major mechanism. Patterns with fluid deficiency in qi aspect syndrome appear mostly in upper or middle energizer and in xue aspect syndrome appear mostly in lower energizer and they form 20% of all syndrome differentiations. The treatment of clearing heat uses pungent-cool(cold) for upper energizer, sweet-cold for middle energizer, sweet(salty)-cold for lower energizer. The treatment of tonifying yin uses mostly salty-cold for middle or lower energizer. The treatment of outthrusting pathogen is applied to all the wei-qi-ying-xue aspect combined with other treatments by using pungent-cool(cold) and light herbs. Understanding diseases in the respect of syndrome differentiation can enhance understanding of modern diseases from a perspective of Korean Traditional Medicinal(KTM) and can make clinical application of KTM treatments easy. Data from this study are expected to be basic for standardization and systemization of KTM.

• The Journal of Korean Medicine
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• v.42 no.3
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• pp.153-164
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• 2021

Objectives: The aim of this study is to investigate the effect of Heat-sensitive Moxibustion on Benign Prostatic Hyperplasia Methods: We searched articles from Academic Journals(CAJ) online databases, Oriental Medicine Advanced Searching Integrated System (OASIS), Searching key words were '前列腺增生', '熱敏灸' and '열민구', '전립선비대'. The search range included randomized controlled trials (RCTs). Among the articles published to 2020, 10 articles were found. After review the title, abstract and original, 3 articles were selected finally to rule out treatment combined with completely different treatments. Result: The Heat-sensitive moxibustion at acupoints in the treatment of Benign prostatic hyperplasia were significantly superior to control group after treatment in the symptoms of patients, IPSS, QOL, PVR and Qmax(P<0.05). The Heat-sensitive moxibustion can significantly reduce the incidence of temporary urinary incontinence after Transurethral resection of the prostate(TURP) and improve life quality and satisfaction of patients(P<0.05). The individualized desensitization saturated time and amount of Heat-sensitive moxibustion is superior effective to general amount and time of traditional moxibustion in the total effective rate, IPSS, Ru and Qmax(P<0.01) for Benign prostatic hyperplasia. Conclusion: Heat sensitive moxibustion directly transfer heat to the source of a disease. So it can be considered as a good treatment for Benign prostate hypertrophy. It was also shown a better effect on BPH compared to traditional moxibustion, According to the thermo principles of tumor, if the tumor cell's death temperature of 43℃ is reached, that can cause tumor degeneration. Therefore I think Heat sensitive moxibustion can be applied to various tumor disease. The results of this study could be applied to clinical treatment of BPH. However, additional large-scale clinical researches should be conducted.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.13 no.3
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• pp.16-22
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• 2017

It has become important for unutilized energy to be used for air conditioning of building. Economic evaluation on energy system by using treated sewage water as heat source, which is one of unutilized energy, was performed. The floor area of the subject building and the distance between heat source equipment and sewage treatment plant was assumed $30,000m^2$ and 200m. Absorption chiller-heater system was used for comparing to the energy efficient system, and payback period method was applied to carry out economic evaluation. Although the operating cost of this system is reduced compared to general heat source system, the ratio is not meaningful compared to the initial investment cost increase, and payback period was calculated to be about 36.1 years. However, when calculated based on the 2014 rate of electricity and city gas, it will be greatly reduced to 3.1 years. International commodity prices are constantly changing, and therefore national policy on the spread of unutilized energy should be maintained.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.229-234
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• 2008

Korea Electric Power Corporation (KEPCO) has started the nation's first biogas-microturbine project in the city of Gongju as an effort to encourage the utilization of wasted biogas containing useful energy source in the form of $CH_4$. The goal of the project is to set up the biogas microturbine co-generation system for utilizing biogas as an energy source and improving the economics of the wastewater treatment plant. Wastewater treatment processes were investigated in depth to find improvement possibility. Changes in internal recirculation ratio and pre-treatment degree are needed to optimize plant operation and biogas production. Biogas pre-treatment system satisfies Capstone's fuel condition requirement with the test result of 99.9% and 90.2% of hydrogen sulphide and ammonia is removal performance. Installation of microturbine and manufacture of heat exchanger to warm anaerobic digester has been done successfully. Expected economic profit produced by the system is coming from energy saving including electricity 115,871kWh/year and heat contained in exhaust gas 579GJ/year.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.30-38
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• 2016

In this research, a 6W white LED package with a Glass Remote Phosphor was developed to improve the life of an LED package. The Glass Remote Phosphor was fabricated by the Phosphor in Glass (PiG) method, wherein phosphor YAG:Ce was mixed with glass frit and then heat treated. A paste with 75wt.% of a phosphor substance and 25wt.% glass frit was coated on a glass substrate two times using the screen-printing technique and heat-treated at $800^{\circ}C$ ; this structure gave a luminous efficacy of 136.1lm/W, color rendering index of 74Ra, and color temperature of 5,342K, thus satisfying the requirements as a light source for lighting. Moreover, an IES LM-80 accelerated life test was conducted on the same LED package for 6,000h in order to estimate the L70 lifetime based on IES TM-21. The results showed guaranteed lifetimes of 213,000h at $55^{\circ}C$, 245,000h at $85^{\circ}C$, and 209,000h at $95^{\circ}C$.

• Korean Journal of Materials Research
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• v.19 no.9
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• pp.457-461
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• 2009

Recently, metal molding has become essential not only for automobile parts, but also mass production, and has greatly influenced production costs as well as the quality of products. Its surface has been treated by carburizing, nitriding and induction hardening, but these existing treatments cause considerable deformation and increase the expense of postprocessing after treatment; furthermore, these treatments cannot be easily applied to parts that requiring the hardening of only a certain section. This is because the treatment cannot heat the material homogeneously, nor can it heat all of it. Laser surface treatment was developed to overcome these disadvantages, and, when the laser beam is irradiated on the surface and laser speed is appropriate, the laser focal position is rapidly heated and the thermal energy of surface penetrates the material after irradiation, finally imbuing it with a new mechanical characteristic by the process of self-quenching. This research estimates the material characteristic after efficient and functional surface treatment using HPDL, which is more efficient than the existing CW Nd:YAG laser heat source. To estimate this, microstructural changes and hardness characteristics of three parts (the surface treatment part, heat affect zone, and parental material) are observed with the change of laser beam speed and surface temperature. Moreover, the depth of the hardened area is observed with the change of the laser beam speed and temperature.

• Korean Journal of Materials Research
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• v.19 no.4
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• pp.207-211
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• 2009

In this study, we attempted to develop a convenient aluminizing process, using Al-Ti mixed slurry as an aluminum source, to control the Al content of the aluminized layer as a result of a one-step process and can be widely adopted for coating complex-shaped components. The aluminizing process was carried out by the heat treatment on disc and rod shaped S45C steel substrates with Al-Ti mixed slurries that were composed of various mixed ratios (wt%) of Al and Ti powders. The surface of the resultant aluminized layer was relatively smooth with no obvious cracks. The aluminized layers mainly contain an Fe-Al compound as the bulk phase. However, the Al concentration and the thickness of the aluminized layer gradually decrease as the Ti proportion among Al-Ti mixed slurries increases. It has also been shown that the Al-Ti compound layer, which formed on the substrate during heat treatment, easily separates from the substrate. In addition, the incorporation of Ti into the substrate surface during heat treatment was not observed.

• Journal of Dairy Science and Biotechnology
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• v.35 no.2
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• pp.121-133
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• 2017

A small amount of milk is sold as 'untreated' or raw in the US; the two most commonly used heat-treatments for milk sold in retail markets are pasteurization (LTLT, low-temperature long time; HTST, high-temperature short time) and sterilization (UHT, ultra-high temperature). These treatments extend the shelf life of milk. The main purpose of heat treatment is to reduce pathogenic and perishable microbial populations, inactivate enzymes, and minimize chemical reactions and physical changes. Milk UHT processing combined with aseptic packaging has been introduced to produce shelf-stable products with less chemical damage than sterile milk in containers. Two basic principles of UHT treatment distinguish this method from in-container sterilization. First, for the same germicidal effect, HTST treatments (as in UHT) use less chemicals than cold-long treatment (as in in-container sterilization). This is because Q10, the relative change in the reaction rate with a temperature change of $10^{\circ}C$, is lower than the chemical change during bacterial killing. Based on Q10 values of 3 and 10, the chemical change at $145^{\circ}C$ for the same germicidal effect is only 2.7% at $115^{\circ}C$. The second principle is that the need to inactivate thermophilic bacterial spores (Bacillus cereus and Clostridium perfringens, etc.) determines the minimum time and temperature, while determining the maximum time and temperature at which undesirable chemical changes such as undesirable flavors, color changes, and vitamin breakdown should be minimized.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1657-1668
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• 1998

In the analysis of a mushy solidification system with natural convection using a fixed grid method, the enthalpy method has been used to account for the release of latent heat. The variable viscosity, Darcy source, and hybrid methods have been employed for the velocity suppression in a mushy region. The choice of the values of solid viscosity and permeability constant in conjunction with the Darcy source term plays an important role in forming the location and shape of the phase boundaries. In this work the effects of these major parameters related to steady-state behavior in the system of mushy solidification are investigated through a simple test problem. The effective specific heat based on the spatial gradients of the enthalpy and temperature is adopted for the treatment of the release of latent heat. The effects of the Prandtl and Rayleigh numbers on the shape of mushy region are examined using the hybrid method.