• 한국진공학회지
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• 제15권5호
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• pp.518-526
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• 2006

나노 다공성 알루미나 박막을 제작하고 이를 주형으로 사용해서 진공증착에 의해 규칙적으로 배열된 나노우물구조와 나노그물구조의 금속 박막들(알루미늄, 주석, 코발트)을 제작하였다. 원하는 금속물질을 증발시키기 위하여 저항가열 방법을 사용하였으며, 증착은 torr의 기저진공 속에서 수행되었다. 실험결과에 의하면, 나노우물과 나노그물 구조의 박막 중 어떤 구조가 합성되느냐 하는 것은 증착되는 물질의 양에 의해서 큰 영향을 받는다는 사실을 알 수 있었다. 세포의 크기가 100 nm이고 세공 직경이 60 nm인 다공성 알루미나 박막을 사용했을 때는 대략 우물구조를 합성하는데 필요한 질량의 절반이하 정도가 증착되게 되면 그물 구조가 합성되는 경향을 보여주었다.

• 한국화재소방학회논문지
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• 제22권2호
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• pp.91-96
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• 2008

본 연구에서는 화재사례를 기반으로 원적외선 히터에서 출화된 화재의 원인 분석에 관하여 연구하였다. 전기히터의 화재는 열선에 용융 흔적으로 판단하여 과열 사고로 취급하는 오류를 범하기 쉽다. 이에 대해 히터의 화재 원인 규명에 있어서 객관적인 자료를 확보하기 위한 방법으로 정상 제품과 비교하여 다양한 재현 실험 및 분석기기를 이용하여 화재 원인을 분석하였다. 열선에 부착된 용융 흔적은 다른 금속 물질에 의한 층간 단락의 형태를 보이나 SEM/EDX로 성분분포를 분석한 결과 철-크롬-알루미늄이 혼합된 열선의 성분이외에 다른 금속 물질은 발견되지 않았다. 또한 층간단락 및 과전압에 의한 과열 실험을 수행한 결과 정상보다 높은 발열 상태를 보이나 화재 가능성은 없었다. 본 논문에서는 원적외선 히터에서 발생한 화재의 원인 분석을 토대로 하여 소손된 전열기의 화염 특성 및 물리 화학적 특성을 입체 분석하여 전기재해 원인 분석의 과학화에 기여하고자 한다.

• 한국태양에너지학회 논문집
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• 제30권5호
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• pp.56-62
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• 2010

The integration of PV modules into building facades or roof could raise their temperature that results in the reduction of PV system's electrical power generation. Hot air can be extracted from the space between PV modules and building envelope, and used for heating in buildings. PV/thermal collectors, or more generally known as PVT collectors, are devices that operate simultaneously to convert solar energy from the sun into two other useful energies, namely, electricity and heat. This paper compares the experimental performance of BIPVT((Building-Integrated Photovoltaic Thermal) collectors that applied on building roof and facade. There are four different cases: a roof-integrated PVT type and a facade-integrated PVT type, the base models with an air gap between the PV module and the surface, and the improved models for each types with aluminum fins attached to the PV modules. The accumulated thermal energy of the roof-integrated type was 15.8% higher than the facade-integrated regardless of fin attachment. The accumulated electrical energy of the roof-integrated type was 7.6% higher, compared to that of the facade-integrated. The efficiency differences among the collectors may be due to the fact that the pins absorbed heat from the PV module and emitted it to air layer.

• 한국세라믹학회지
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• 제22권3호
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• pp.35-40
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• 1985

The composition of the base glass was determined to be $Na_2O$ 15, $Fe_2O_3$ 35, $B_2O_3$ 0~20, $P_2O_5$ 30~50 by mole percent. The heating temperature for nucleation was determined by means of thermal expansion curve. Crystalline phases were investigated by X-ray diffraction method and I.R Spectra. Electrical conductivities of glass spec-imens were observed in the temperature range 25~20$0^{\circ}C$ The activation energies of these specimens were caculated. The results obtained were as follows : 1) The limit composition of the melts 15mol% $Na_2O$ 35mole% $Fe_2O_5$ 20mole% $B_2O_3$ 30mole% $P_2O_5$ was able to be formed into desired shapes during cooling, . 2) In the measurement of d. c conductivity($\delta$) on the glasses in the system $15Na_2O-35Fe_2O_3$-$B_2O_3$-(50-x) $P_2O_5$ the values decreased by replacing 5 mole% $P_2O_5$ with $B_2O_3$ 3) The d. c conducties of heat treated samples were increased by replacing $P_2O_5$ with $B_2O_3$ 4) $B_2O_3$ contributed to precipitate crystals such as${\gamma}$-$Fe_2O_3$ $Fe_3O_4$ which had the advantage of electronic conduction in heat treated samples. 5) The slope plotted Log($\delta$) versus 1/T in this glass system was linear in the measured temperature range.

• 대기
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• 제24권4호
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• pp.457-470
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• 2014

Thermodynamic conditions related with localized torrential rainfall in the middle west region of Korean peninsula are examined using radar rain rate and radiosonde observational data. Localized torrential rainfall events in this study are defined by three criteria base on 1) any one of Automated Synoptic Observing System (ASOS) hourly rainfall exceeds $30mmhr^{-1}$ around Osan, 2) the rain (> $1mmhr^{-1}$) area estimated from radar reflectivity is less than $20,000km^2$, and 3) the rain (> $10mmhr^{-1}$) cell is detected clearly and duration is short than 24 hr. As a result, 13 cases were selected during the summer season of 10 years (2004-13). It was found that the duration, the maximum rain area, and the maximum volumetric rain rate of convective cells (> $30mmhr^{-1}$) are less than 9hr, smaller than $1,000km^2$, and $15,000{\sim}60,000m^3s^{-1}$ in these cases. And a majority of cases shows the following thermodynamic characteristics: 1) Convective Available Potential Energy (CAPE) > $800Jkg^{-1}$, 2) Convective Inhibition (CIN) < $40Jkg^{-1}$, 3) Total Precipitable Water (TPW) ${\approx}$ 55 mm, and 4) Storm Relative Helicity (SRH) < $120m^2s^{-2}$. These cases mostly occurred in the afternoon. These thermodynamic conditions indicated that these cases were caused by strong atmospheric instability, lifting to overcome CIN, and sufficient moisture. The localized torrential rainfall occurred with deep moisture convection result from the instability caused by convective heating.

• Fisheries and Aquatic Sciences
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• 제20권7호
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• pp.13.1-13.7
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• 2017

In order to evaluate the maximal storable period of the raw crab for a non-thermal muscle separation, the quality changes of the leg meat of red snow crab (Chionoecetes japonicus) during freeze storage were investigated. Fresh red snow crabs were stored at $-20^{\circ}C$ for 7 weeks, and the leg muscle was separated by a no heating separation (NHS) method every week. During the storage, considerable loss of the leg muscle did not occur and microbiological risk was very low. In contrast, discoloration appeared at 2-week storage on around carapace and the leg muscle turned yellow at storage 3-week. In physiochemical parameters, protein and free amino acids gradually decreased with storage time, expected that proteolytic enzymes still activated at $-20^{\circ}C$. At 4-week storage, the sensory acceptance dropped down below point 4 as low as inedible and notable inflection points in pH and acidity were observed. The volatile base nitrogen was low, though a little increase was recorded. These results suggested that the maximal storable period at $-20^{\circ}C$ of the raw material was within 2 weeks and it was depended on external factor such as the discoloration. The present study might be referred as basic data for approaches to solve quality loss occurred in non-thermal muscle separation.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.8-8
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• 2002

TiC core/(Ti,Mo)C rim structure in TiC-$Mo_2C$-Ni base cermet which is generally prepared by sintering below 145$0^{\circ}C$ had been believed to be generated by the solid diffusion of Mo atoms 1 into TiC grains (D. Moskowitz and M.Humenik, 1r.:1966). Afterward, it was clarified that the c core/rim structure is generated by solution/re-precipitation mechanism : (1) $Mo_2C$ grains and s small TiC grains dissolve into the Ni liquid, (2) the dissolved Mo, Ti and C atoms migrate to the s surface of TiC coarse grains, (3) the Mo, Ti and C precipitate on the surface of TiC coarse g grains and form (Ti,Mo)C solid solution rim, and (4) the Ostwald ripening (grain growth by s solution/re-precipitation mechanism) of TiC-core/(Ti,Mo)-rim grains continues, and thus the w width of (Ti,Mo)C rim (at the same time, the grain size) increases with sintering time, etc. ( (H.Suzuki, K.Hayashi and O.Terada: 1973). The TiC-core was found not to disappear even by s sintering at 190$0^{\circ}C$ (ibid.: 1974) Recently, FeSi core/$Fe_2Si_5$-rim structure in Fe-66.7at%Si thermoelectric aIloy was found to also h hardly shrink and disappear by long heating at an appropriate temperature (1999: M.Tajima and K K.hayashD. Then, the authors considered its cause, and clarified experimentaIly that the disappearance of FeSi-core/$Fe_2Ski_5$-rim structure could be attributed to the exhaustion of diffusion-contributable vacancies in core/rim structure (N.Taniguchi and K.Hayashi:2001). At p present, the authors and my coworker are investigating whether the non-disappearance of TiC c core can be explained also from the new hypothesis "Exhaustion of diffusion-contributable v vacancies in corelrim structure".ure".uot;.

• 한국염색가공학회지
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• 제26권2호
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• pp.88-98
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• 2014

This study is to assess the photocatalytic degradation of PET and Nylon 6 films containing nano-sized $TiO_2$ powders of anatase and rutile types. The PET and Nylon 6 films containing six kinds of the nanoparticles were prepared by melt casting method using a heating press machine. Reflectance in visible region and water contact angles of the irradiated PET and Nylon 6 composite films decreased with increasing UV/$O_3$ irradiation. Also the enhanced hydrophilicity has a close relationship with the increase in the Lewis base parameter, which indicates more oxidized polymer surfaces. The photocatalytic degradation of the nanocomposite films increased with increasing $TiO_2$ content and UV energy, which is more significant with the anatase types rather than the rutile types. The amide linkages in the Nylon 6 seemed to be more susceptible to the UV light compared to the ester groups in the PET, particularly in the presence of the $TiO_2$ photocatalysts. The photoscission and photodegradation of the polymers in the composites produced more degraded structure assisted by the photocatalytic activity of the $TiO_2$ nanoparticles. Also the composite films can bleach the methylene blue dyes more easily under the UV/$O_3$ irradiation, suggesting the photobleaching activity of the $TiO_2$ nanoparticles.

• 한국식품조리과학회지
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• 제8권2호
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• pp.95-105
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• 1992

This study was carried on the Seasoning Oil production by Autoclaving Method in order to research a developed method. The Raw, Extract states of seasoning vegetables-Garlic, Onion and Ginger were added 40, 60% (w/w) of total amounts to corn salad oil. All samples treated with various conditions were determined physicochemical characteristics by Acid value, Peroxide value, Iodine value, Refractive Index, and Volatile Carbonyl Compound Content during incubating $(40{\pm}2^{\circ}C)$ and heating $(185{\pm}2^{\circ}C)$. The results were obtained as follws; 1. During incubation at $40{\pm}2^{\circ}C$, the order of antioxidative effects among seasoning vegetables was Ginger>Garlic>BHA>Onion and Extract state were more effective man Raw state. also the antioxidative effects of the seasoning vegetables were increased proportionally with the concentration in the Seasoning Oils. 2. In the case of heat treatment $(185{\pm}2^{\circ}C)$, AV, POV, IV and RI of each Seasoning Oil were changed very sharply. The antioxidative effect and Carbonyl Compound Content according to heat treatment differed from the type and concentration of seasoning vegetables in oil. Ginger had the most excellent antioxidative effect among seasoning vegetables, and m any case, the adding states of seasoning vegetables into oils were more effective in Extract man Raw states. 3. According to those results, each Seasoning Oil made from Garlic, Onion, Ginger was shown to have antioxidative properties specially in Ginger-Extract-Seasoning Oil. also the Autoclaving Method was thought to be rational method in preparation of Seasoning Oil.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.127-132
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• 2011

Worldwide, the building energy simulation becomes inevitable step for predicting the energy consumption in building. In simulation process, the expertise is required for the accurate analysis results. In Korea, however, most of user use the inconsistent data with Korea circumstance. In this step, we need to construct the standard input data matched building in Korea. In this study, electricity consumption of apartments in Daejeon is analyzed. The yearly data of a apartment complexes of 2009 are analyzed as monthly, daily(week and weekend), timely, and completion year. With this result, we are able to predict the demand pattern of electricity in a house and make the schedule by demand pattern. The results of this study are followed. The averaged amount of electricity consumption in winter is higher than summer because of the high capacity of heating equipment. All of the house has electric base load from 0.26kWh to 0.5kWh. The average of the electricity consumption of month is shown as 326.7kWh. A week is seperated as 4 part such as week, weekend, Saturday and Sunday. During week, the average of timely electricity consumption is shown as 0.442kWh. The Saturday consumption is 0.453kWh. The Sunday is 0.461kWh.