• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.569-573
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• 1998

This study was conducted to investigate the differences of textural characteristics and microstructure of sugared chestnuts between heated by a heater and microwave. Raw chestnuts were boiled and infiltrated the sugar in sugar syrup by heating. The content of WSP (water soluble pectin) was increased, but HSP (hydrochloric acid soluble pectin) was decreased by boiling and sugaring. This change was remarkable when it was boiled and sugared by a microwave heating. The hardness, gumminess and chewiness were more decreased in the sugared chestnut boiled and sugared with a microwave than that processed with a heater. Microstructure of sugared chestnut processed with a microwave heating showed the distruction of cell wall.

• International Journal of Air-Conditioning and Refrigeration
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• v.13 no.1
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• pp.51-60
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• 2005

This paper reviews the studies on the pressure drop and the heat transfer in microchannels. Although a lot of studies about the single-phase flow have been done until now, conflicting results are occasionally reported about flow transition from laminar flow to turbulent flow, friction factor, and Nusselt number. Some studies reported the early flow transition due to relatively greater wall effect like surface roughness, but the other studies showed that the flow transition occurred at the Reynolds number of about 2300 and the early flow transition might be due to less accurate measurement of the channel geometry. Also, there have been arguments whether the conventional relation based upon continuum theory can be applied to the fluid flow and the heat transfer in microchannels without modification or not. The studies about the two-phase flow in microchannels have been mostly about investigating the flow pattern and the pressure drop in rectangular channels using two-component, two-phase flow like air/water mixture. Some studies proposed correlations to predict two-phase flow pressure drop in microchannels. They were mostly based on Lockhart-Martinelli model with modification on C-coefficient, which was dependent on channel geometry, Reynolds number, surface tension, and so on. Others investigated the characteristics of flow boiling heat transfer in microchannels with respect to test parameters such as mass flux, heat flux, system pressure, and so on. The existing studies have not been fully satisfactory in providing consistent results about the pressure drop and the heat transfer in microchannels. Therefore, more in-depth studies should be done for understanding the fundamentals of the transport phenomena in the microchannels and giving the basic guidelines to design the micro devices.

• Applied Science and Convergence Technology
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• v.23 no.5
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• pp.248-253
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• 2014

Air Gap Membrane Distillation (AGMD) is one of several technologies that can be used to solve problems fresh water availability. AGMD exhibits several advantages, including low conductive heat loss and higher thermal efficiency, due to the presence of an air gap between the membrane and condensation wall. A previous study by Bhardwaj found that the condensation surface properties (materials and contact angle) affected the total collected fresh water in the solar distillation process. However, the process condition differences between solar distillation and AGMD might result in different condensation phenomena. In contrast, N. Miljkovic showed that a hydrophobic surface has higher condensation heat transfer. Moreover, to the best of our knowledge, there is no study that investigates the effect of condensation surface properties in AGMD to overall process performance (i.e. flux and thermal efficiency). Thus, in this study, we treated the AGMD condensation surface to make it hydrophobic or hydrophilic. The condensation surface could be made hydrophilic by immersing and boiling plate in deionized (DI) water, which caused the formation of hydrophilic aluminum hydroxide (AlOOH) nanostructures. Afterwards, the treated plate was coated using hexamethyldisiloxane (HMDSO) through plasma-enhanced chemical vapor deposition (PECVD). The result indicated that condensation surface properties do not affect the permeate flux or thermal efficiency significantly. In general, the permeate flux and thermal efficiency for the treated plates were lower than those of the non-treated plate (pristine). However, at a 1 mm and 3 mm air gap, the treated plate outperformed the non-treated plate (pristine) in terms of permeate flux. Therefore, although surface wettability effect was not significant, it still provided a little influence.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.7
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• pp.380-394
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• 2015

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.46-57
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• 2014

This study contemplated the gardening culture from the pictures, which the scholars of late Joseon Dynasty, the aspects of garden landscapes and garden use behaviors are drawn as follows. 1. The yard by the detached house for men and guest in front of the premises(Sarang Madang) and backyard were the major places for Ahoi(social gatherings of the scholars). The mansions had interests in the management of the outer garden beyond the house wall with building structures like the pavilions on the high walls and side gates. This management and the selection of location anticipating in advance of the management are noteworthy. 2. Only house gardens had plant pots with flowers and the small flower bed(Hwa-O) at Sarang Madang occasionally had plant pots without flowers and oddly shaped stone pots and equipped pine branch eaves and traditional awnings made of plant material like a trellis. 3. The oddly shaped stones were significant landscape elements in the gardens of houses and villas. Some of them were depicted as the Taihu stone and this draws attention to the question of whether the Taihu stone was actually used in the garden of late Joseon Dynasty. 4. The gardens in villas accommodated the borrowed scenery with various materials like wooden fences, bamboo or reed fences, mud walls. They also had the artificial gardens with some odd shaped stones, old pines, bamboos, Japanese apricots, willows, paulownia trees, lotuses and plantains in the secured Madangs. 5. Gyeong Hwa Sa Jog(The scholars of the ruling class adapted to the 18th century's new historical aspect) of late Joseon Dynasty built the villas at the beautiful scenery closed to the their houses. 6. The Gardens around pavilions were located high closed to the mountain streams with nature like beautiful forests, oddly formed rocks, precipitous cliffs and viewing stones. The back side of the pavilion was enclosed by bamboo forests and the front had pines, ginkgoes and willows as shade trees. 7. The beautiful scenery which was preferred as the place for Ahoi was basically with fantastic peaks and precipitous cliffs which forms the distant view harmonized with a waterfall. Broad and flat rocks at the summit of a mountain which commands a bird's-eye view or on a mountain streamside with pine forest, willows and plum trees were chosen as the optimal places for Ahoi. 8. Pine trees were presumed to be more preferable than other species in the garden, especially an single planted old pine tree accented symbolism. 9. Portable tea braziers for boiling tea were adopted in all four types of the gardens. 10. The gardens mixed with auspicious landscape elements were the places of the arts for an unworldliness Ahoi through GeumGiSeoHwa(enjoying strings, go, writing and painting) and boiling tea.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.3
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• pp.224-238
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• 2008

The aim of this study is to confirm the physicochemical property and hazard of thinner (012), which is a diluent of enamel paint used for floor coating for waterproofing and oil painting for the outer wall. The literatures of physicochemical property and hazard of thinner were surveyed and its physicochemical property were evaluated. And then, the inhalation toxicity of thinner affecting the central nervous system and reproductive organs in rats were examined by subchronic (6 h./day. 5 days/ week for 13 weeks) inhalation test. 1) According to the 13-week subchronic inhalation test, there were no significant changes in clinical test and body weight. However, a significant evidence of toxicity was observed in the hematological test and organ weight such as heart, kidney, liver and brain (p<0.01) in the 200 ppm and 1,000 ppm exposure groups in a dose response manner. In the histopathology analysis, there were no significant evidence of toxicity. Therefore, thinner was not classified as an organ targeted toxic agent. In case of Harmfulness, it could be classified as a chronic toxic agent 3($500 ppm/4hr, rat). 2) The reproductive toxicity such as extension of the period of estrous cycle, reduction of serum estradiol concentration and increase of frequency of the abnormal sperm was observed in the 1,000 ppm exposed animals. 3) The result of the physicochemical property of the test material showed that the specific gravity was 0.793, boiling point $155.8^{\circ}C$, steam pressure 2.1 kPa, ignition point $34.5^{\circ}C$, and spontaneous ignition point $280^{\circ}C$. The endothermic and exothermic values were 371.4 J/g and 159.1 J/g. respectively. The explosion limit was 214 mg/l. These data showed that thinner could be classified as an explosion agent level 1.2 and ignitive liquid agent 3 ($23-60^{\circ}C$) according to the notification No. 2008-1 of the Labor Ministry, "Classifying Standard of Chemical Materials."

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1033-1044
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• 2015

During the Joseon period, kimchi was mostly made by heating the ingredients. Since salt was pricey at the time, in order to save salt and time, people used a method that involved destroying the cell wall by heating the vegetables. However, this method is no longer passed down. Thus, in this paper, we re-discovered how kimchi was made through heating while analyzing the recipes for kimchi during the Joseon period. There were 27 kinds of kimchi made through blanching. To keep the vegetables from becoming soggy, 2 kinds of kimchi were made by putting the ingredients in potassium aluminum sulfate water and 3 kinds were made through blanching the ingredients in limewater. There were 7 kinds of kimchi made by heating in vinegar, 5 kinds by boiling the ingredients, 6 kinds by stir-frying the ingredients, 2 kinds by stir-frying the ingredients with salt, and 3 kinds by steaming the ingredients. In order to eradicate unwanted germs, leaving only Lactobacillus, 25 kinds of kimchi were made by draining the boiled mixture. A total of 17 kinds of kimchi were made by heating the kimchi pot with compost including that of horses. For elders with weak teeth and poor digestion, 7 kinds of kimchi were made after heating, including 3 kinds of sukkkakdugi (cubed radish kimchi made with boiled radish). 3 kinds of chaekimchi (julienned kimchi) and 3 kinds of chaekkakdugi (kimchi with julienned radish) for elders existed as well.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.35-40
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• 2008

A distillation tower is one of the important facilities which separates and refines a crude oil stream according to certain boiling points. Its operation efficiency can affect the productivity of a refinery substantially. The objective of this study is to elucidate some operational information on the internal conditions of a distillation tower from a measurement of density profile by using a sealed gamma-ray source and a radiation detector. Gamma radiation counts were measured by a BGO detector positioned diametrically outside the tower-wall, opposite to the gamma source(Co-60) as the detector and the source were lowered concurrently. From the results, structural abnormality of the trays was not found inside the tower. Considering the flow distribution patterns, however, a vapor phase was dominantly formed at the upper part of the tower and a liquid phase at the lower part. From the gamma scanning of the distillation tower, it is anticipated that the gamma absorption technique can be used as an important tool for confirming the structural soundness of trays and investigating flow distribution in refinery facilities.

• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.87-102
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• 2019

Pallancata Ag mine is located at the Ayacucho region 520 km southeast of Lima. The geology of mine area consists of mainly Cenozoic volcanic-intrusive rocks, which are composed of tuff, andesitic lava, andesitic tuff, pyroclastic flow, volcano clasts, rhyolite and quartz monzonite. This mine have about 100 quartz veins in tuff filling regional faults orienting NW, NE and EW directions. The Ag grades in quartz veins are from 40 to 1,000 g/t. Quartz veins vary from 0.1 m to 25 m in thickness and extend to about 3,000 m in strike length. Quartz veins show following textures including zonation, cavity, massive, breccia, crustiform, colloform and comb textures. Wallrock alteration features including silicification, sericitization, pyritization, chloritization and argillitization are obvious. The quartz veins contain calcite, chalcedony, adularia, fluorite, rutile, zircon, apatite, Fe oxide, REE mineral, Cr oxide, Al-Si-O mineral, pyrite, sphalerite, chalcopyrite, galena, electrum, proustite-pyrargyrite, pearceite-polybasite and acanthite. The temperature and sulfur fugacity ($f_{s2}$) of the Ag mineralization estimated from the mineral assemblages and mineral compositions are ranging from 118 to $222^{\circ}C$ and from $10^{-20.8}$ to $10^{-13.2}atm$, respectively. The relatively low temperature and sulfur-oxygen fugacities in the hydrothermal fluids during the Ag mineralization in Pallancata might be due to cooling and/or boiling of Ag-bearing fluids by mixing of meteoric water in the relatively shallow hydrothermal environment. The hydrothermal condition may be corresponding to an intermediate sulfidation epithermal mineralization.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.395-401
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• 2002

The combination of early heading time, maturing time and short grain-filling period is very important to develop early varieties in winter barley. The 4 parental half diallel crosses (parents, $F_1$s, $F_2$s) were cultivated at the field. The heading date was from April 3 to 26, maturing date from May 15 to 27 and grain-filling period from 31 days to 42 days, showing that the varietal differences about the 3 traits were remarkable. According to half diallel cross analyses, Dongbori 1 for heading time (late heading) was dominant, but Oweolbori (early heading) was recessive, showing partial dominance with high additive component of genetic variance. Dongbori 1 for maturing time was dominant, but Oweolbori was recessive, showing partial dominance with high additive variance. Reno for grain-filling period (short grain-filling period) was dominant, but Oweolbori (long grain-filling period) was recessive with additive, and partial dominance. There were highly significant mean squares for both GCA and SCA effects on the heading and maturing times, and GCA/SCA ratios for all traits were high, showing the additive gene effects more important. Sacheon 6 and Oweolbori had greater GCA effects for early heading and maturing times, and Dongbori 1 and Reno had greater GCA effects for late times. GCA effects were highly significant in $F_1$ and $F_2$ generations, showing high GCA/SCA ratios (7.02). The heading and maturing times in field were positively correlated with antifreeze proteins concentrations, accumulation, resistance to photoinhibition and winter survival, respectively) but the grain-filling period did negatively correlated with the trails.