• Journal of the Korean GEO-environmental Society
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• v.2 no.3
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• pp.17-35
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• 2001

In this study, we conducted a combined adsorption-sequential extraction analysis(CASA) to investigate temperature effects of single adsorption of lead, copper, zinc and cadmium on natural clays. As a result, it was found that in a single adsorption of lead and copper, about 50% of adsorption was occluded in carbonate phase, and in case of cadmium, about 80% of adsorption was occluded in exchangeable phase. At temperature below $25^{\circ}C$ about 60% of zinc was occluded in exchangeable phase but above $40^{\circ}C$ about 50% of zinc was occluded in carbonate phase. The effect of temperature on each occluded phase was largely observed in Fe-oxide, Mn-oxide and organic occluded phases. Besides, the adsorption of metals on natural clays was an endothermic reaction with the exception of exchangeable phase adsorption.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.32-38
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• 2009

The hatching rate of the eggs of Triops longicaudatus (LeConte), an endangered tadpole shrimp species in Korea, was experimented in different levels of temperature (10, 15, 20, 25, 30, 35, 40, 45, and $50^{\circ}C$) under 24 L photoperiod conditions in incubator. Eggs of T. longicaudatus in this study were obtained from the adults collected from Andong-si, Gyeongsangbuk-do, Korea, in July 2006. The highest hatching rate was the 80.0 (${\pm}9.43$)% in average at $35^{\circ}C$. The thermal threshold for hatching was derived at $6.66^{\circ}C$. However, eggs were not hatched both at $10^{\circ}C$ and at $50^{\circ}C$ during the experimental period.

• Bulletin of the Society of Naval Architects of Korea
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• v.11 no.1
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• pp.35-44
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• 1974

열박음(shrink fitting)으로 인(因)한 동심형(同心形) 구멍을 가진 복합(複合)실린더의 과도적(過渡的) 온도분포(溫度分布), 열응력(熱應力) 및 열변형도(熱變形度)를 이론해석(理論解析)하였다. 온도분포해석(溫度分布解析)에서 외부(外部) 실린더는 균일온도(均一溫度)로 가열(加熱)되어, 실온(室溫)의 내부(內部) 실린더와 접촉면(接觸面)에서 일어나는 열전도(熱傳導)에 의(依)하여 냉각(冷却)되고, 외부(外部) 표면(表面)은 대기중(大氣中)에 노출(露出)된 상태(狀態)로 취급(取扱)하였다. 열응력(熱應力)은 평면변형도조건(平面變形度條件)을 만족(滿足)하는 것으로 생각하였으며, 물성(物性)은 온도(溫度)에 무관(無關)한 상수(常數)로 취급(取扱)하였다. 온도분포(溫度分布)는 열전도문제(熱傳導問題)만을 고려(考慮)함으로서도 유효(有效)한 해(解)를 얻을 수 있으며 열응력(熱應力)은 접촉면(接觸面)에서부터 형성(形成)되며, 반경방향응력(半徑方向應力)은 시간(時間)이 경과(經過)함에 따라 압축응력(壓縮應力)이 증가(增加)하여 접촉면(接觸面)에서 최대치(最大値)를 갖고, 원주방향응력(圓周方向應力)은 접촉면(接觸面)에서 초기(初期)부터 거의 최종상태(最終狀態)와 같은 크기를 갖음을 알 수 있다. 균일온도분포(均一溫度分布)가 이루어지면 열응력(熱應力)의 형성(形成)은 완료(完了)되게 되며, 이때의 열응력(熱應力)의 크기와 분포경향(分布傾向)은 평면응력조건(平面應力條件)을 사용(使用)하였다는 사실(事實)을 고려(考慮)하면 $Lam\acute{e}$의 이론해(理論解)와 일치(一致)함을 알 수 있었다.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.332-337
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• 2023

This study aimed to assess the effect of temperature alterations on the preservation of egg quality and determine suitable temperature management practices for unwashed eggs contaminated with Salmonella Enteritidis on their shells in an actual distribution environment. Unwashed eggs inoculated with Salmonella Enteritidis were stored for 7 d under six different conditions, constant temperature storage at 25℃ and five different temperature-changing storage conditions. For the temperature-changing conditions, the eggs were initially stored at 25℃, and then the temperature was changed to either 10 or 35℃. The indicators of egg quality, air cell height, weight loss, and specific gravity were preserved in the initial measurements when the storage temperature was lowered from 25 to 10℃ from day 3 to 4 after inoculation with Salmonella Enteritidis. In addition, the thick albumen ratio did not show significant alteration caused by the storage conditions when compared with that of fresh eggs. These findings indicate that lowering the storage temperature from 25 to 10℃ is appropriate for the safety management of unwashed eggs during actual distribution.

• Korean Journal of Optics and Photonics
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• v.29 no.6
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• pp.241-246
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• 2018

In this paper, a low-cost optical temperature sensor is implemented, using a fiber Bragg grating (FBG) as the temperature probe and a low-cost VCSEL with temperature-dependent output wavelength as the light source. To analyze the wavelength of the reflected light from the FBG, an interrogation was applied using a method of referring to the internal temperature according to the output wavelength of the VCSEL. When the temperature of the VCSEL was adjusted from 14 to $52.2^{\circ}C$, the output wavelength varied from 1519.90 to 1524.25 nm. The degree of wavelength tuning according to temperature was $0.114nm/^{\circ}C$. The variable wavelength repeatability error according to temperature was ${\pm}0.003nm$, and the temperature measurement error was ${\pm}0.18^{\circ}C$. As a result of measuring the temperatures from 22.3 to $194.2^{\circ}C$, the value of the internal temperature change of the light source according to the applied temperature ${\Delta}T$ was $0.146^{\circ}C/{\Delta}T$, the change in reflected wavelength of the temperature probe according to applied temperature ${\Delta}T$ was measured at $16.64pm/^{\circ}C$. and the temperature measurement error of the sensor was ${\pm}1^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.921-927
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• 2015

The aim of this study was to investigate the effect of die temperature and repeated extrusion on physical properties of extruded white ginseng (EWG). The die temperature was adjusted to 100, 120, and $140^{\circ}C$, and extrusion was repeated under the same conditions with their corresponding samples. Specific mechanical energy input decreased as die temperature increased during extrusions. The secondary extruded white ginseng (SEWG) at a die temperature of $120^{\circ}C$ showed a higher expansion index than other extrudates. Elevation of both die temperature and repeated extrusion increased the specific length of extrudates. The highest apparent elastic modulus, breaking strength, and water solubility index obtained from SEWG at a die temperature of $100^{\circ}C$ were $7.53{\times}10^8N/m^2$, $7.49{\times}10^5N/m^2$, and 39.02%, respectively. When die temperature increased, water absorption index (WAI) decreased. The WAI of SEWG was higher than that of EWG. In conclusion, repeated extrusion affected physical properties of white ginseng and could be applied to produce improved quality of ginseng products.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.556-561
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• 1996

주증기관 파단사고가 발생하여 서로 다른 온도 및 유속을 갖는 냉각재가 원자로 용기에 유입 될 때 downcomer 및 lower plenum 에서의 혼합현상을 3차원 열수력 분석코드 COMMIX-lB［1］로 모사하여 노심입구에서의 온도분포를 결정하고, 결정된 온도분포를 이용하여 주증기관 파단사고에 대한 열적여유도를 분석하였다. 분석은 주증기관 파단사고시 노심입구온도의 비대칭성이 가장 큰 고리 1호기를 선택하여 수행되었으며, 15주기 교체노심 설계 결과와 비교하여 열적 여유도가 다소 증가함을 확인하였다.

• Product Safety
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• s.182
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• pp.54-57
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• 2009

전기기기는 통상 사용 후 고온부로 인해 회로적 과부하, 부품 고장 및 절연 파괴 등 어떠한 위험요서에 노출되어서는 안 된다. 또한 통상온도 상승 시험 후 감전 및 상해 대한 추가 시험이 반드시 뒤 따르게 되어 있다. 따라서 전기기기의 안전성을 판단하기 위해서 통상온도 상승 시험은 기본 사항이며, 필수적이라 할 수 있다. 본고에서는 전기용품안전기준 K60335-1의 제1부 규격과 개별 규격을 근거로하여, 통상 상태 즉 정상 상태 일 때 일반적인 온도 상승 시험장법 및 적합성에 대해서 설명한다. 또한 각 전기기기별로 온도 시험을 위해서 설치 조건, 동작 시간 및 적합성에 대해서 제시하고자 한다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.12a
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• pp.166-169
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• 2002

본 논문에서는 사출성형기의 배럴의 정밀 온도제어에 대해 논의하였다 현재 사출성형기의 온도제어는 온도 편차가 2도 내외이며, 예열후 안정화되는데 걸리는 시간이 길다는 단점이 있다. 향후 마이크로-나노 시스템 제작 공정에 있어서 대량생산 방법으로 사출성형이 주목받을 것으로 기대된다. 특히 온도 제어의 경우는 사출시 인가해야 할 온도가 녹는점 및 glassy 온도에서 유지가 되면서 충분히 유동을 가지는 온도를 지속적으로 유지를 해야하므로 사출 후 정밀성에 중요한 요소가 된다. 마이크로-나노 사출공정은 극 미세 사출이며 온도, 압력에 따른 재료 특성 변화가 발생할 수 있으므로 이를 최적의 조건으로 제어할 수 있어야 한다. 본 연구에서는 실제 사출성형기와 PC based PLC를 이용한 온도제어기를 구현하고 실험하였다. 이를 통해 기존의 온도제어의 단점을 줄이고, 제어성능을 극대화하여 향후 마이크로-나노 시스템에 적용 가능한 정밀 온도제어기를 제안한다.

• Membrane Journal
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• v.23 no.3
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• pp.245-250
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• 2013

In this study, the pervaporation separation characteristics were investigated for the iso-propyl alcohol (IPA)-water system using PDMS dense membranes. The ratio, 9:1 and 10:1, of the basic material based on RTV-655 and crosslinking agent were used to prepare dense membranes at the reaction temperatures, 40, 60, and $80^{\circ}C$. And these resulting membranes were characterized by pervaporation technique in terms of permeabilities and separation factors for the feed composition of IPA 85 wt% at the operating temperatures, 25, 35, 45, and $55^{\circ}C$. Typical results of permeabilities $148g/m^2{\cdot}hr$ at $55^{\circ}C$ for 9:1 membrane and the selectivity 17 at $55^{\circ}C$ for 10:1 membrane were obtained, respectively.