• 한국식품저장유통학회지
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• 제5권2호
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• pp.111-117
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• 1998

Biochemical property changes of garlic during various storages and marketing after storage were investigated. Content of enzymatic pyruvic acid increased by room and low temperature storage but decreased by CA and MA storage. Fructan contents decreased rapidly by low temperature storage, but restrained decrement by CA and MA storage. Free sugar increased during storage, but did slowly by room temperature storage. Green pigment development was observed when garlics stored for 90days at low temperature were processed into crushed form. This discoloration was small for garlics stored in CA and MA, and never occurred for room temperature stored garlics. When marketed after storage, content of enzymatic pyruvic acid decreased in garlic stored in room and low temperature storage, but increased in garlics which decreased during CA and MA storage. Fructan contents deceased but free sugar contents continuously increased with marketing period. Green pigment development decreased in crushed garlic after 30days at room temperature marketing, but increased in low temperature marketing with marketing time progress.

• 한국화재소방학회논문지
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• 제13권1호
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• pp.3-10
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• 1999

천연섬유분진의 연소특성을 조사하고자 국내 방적공장의 집진기에서 직접 포집된 천연섬유분진을 열시차 및 열중량 분석기를 이용하여 온도에 따른 분해 특성을 조사하였고, 자연발화 시험기를 이용하여 시료의 입도분포 및 시료량에 따른 천연섬유의 연소특성을 시간에 따른 온도의 변화로 측정하였다. 또한 자연발화 시험기 내부의 공기흐름에 따른 연소특성을 조사하고자 송풍과 무풍 상태에서의 자연발화 또는 훈소특성을 조사하였다. 열분석 결과 승온속도가 증가할수록 발열개시온도가 현저히 낮았고 발열량도 크게 증가하였다. 또한, 천연섬유 분진은 시료량과 입도가 증가할수록 발열개시온도가 낮아지고 있으며, 연소형태는 모두 훈소 상태를 보였다. 시험기 내부가 송풍상태일 때 보다 무풍상태로 실험하였을 때 발열개시온도가 약간 낮으며, 발열량도 크게 나타났다.

• 한국자동차공학회논문집
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• 제17권5호
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• pp.31-38
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• 2009

Supercharging system was adopted to investigate the influence of boost pressure on operating range and exhaust emissions by using a supercharger at low temperature diesel combustion (LTC) condition in a 5-cylinder 2.7 L direct injection diesel engine. The experimental parameters such as injection quantity, injection timing, injection pressure and exhaust gas recirculation (EGR) rate were varied to find maximum operating range in LTC condition. As a result of adopting increased boost pressure in LTC, wider operating range was achieved compared with naturally aspirated condition due to increased mixing intensity. Increased boost pressure resulted in lower hydrocarbon (HC) and carbon monoxide (CO) emissions due to increased swirl rate and mixing intensity, which induced complete combustion. Moreover, increased boost pressure in LTC resulted in much lower soot emissions compared with high speed direct injection (HSDI) condition.

• 한국환경과학회지
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• 제17권5호
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• pp.485-491
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• 2008

The present study examined the relation between land cover condition and temperature in various types of urban green spaces. The diagram of temperature distribution showed that high-temperature zones are formed around paved areas, and low temperature zone around planted areas and grassy areas. Even in planted areas where low-temperature zones were formed, temperature was different according to hierarchical structure. That is, temperature was relatively low in areas covered with arbor + sub-arbor. With regard to land cover ratio, the increase of planted areas and grassy areas had an effect on the fall of temperature and the effect was higher in order of planted areas and grassy areas. On the contrary, paved areas and bare areas had an effect on the rise of temperature. According to the results of factor analysis, in case of the highest temperature, planted area and grassy area were put together into a factor lowering temperature, paved area and temperature into a factor raising temperature, and bare area alone into a factor of low significance. In case of the lowest temperature, grassy area and bare area were put together into a factor, and the validity of the factor analysis was proved by the analysis of urban heat islands. An increase in the number of trees by height was effective in lowering temperature, and the effect was high in order to arbor and sub-arbor, and the source of coldness in planted area was tall trees.

• 한국화재소방학회논문지
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• 제15권2호
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• pp.1-5
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• 2001

전분 분말의 온도에 따른 열적 안정성을 조사하기 위하여 시차주사열량계(DSC, Differential Scanning Calorimeter) 빛 열중량 분석기(TGA, Thermogravimetric Analysis)를 이용하여 온도에 따른 발열개시 온도, 발열량 등을 조사하였으며, 자연발화 시험기를 이용하여 시료량에 따른 전분 분말의 연소특성을 시간에 따른 온도의 변화를 측정하여 연소개시시간 및 연소시 상승하는 온도를 측정함과 동시에 육안으로 연소특성을 조사하고자 하였다. 한편 자연발화 시험기 내부의 공기흐름에 따른 연소특성을 조사하기 위하여 송풍과 무풍 상태에서의 연소특성을 조사하고자 하였다. 선분 분말의 열분석 결과 승온속도가 증가할 수록 발열개시온도가 저온부로 이동하고 있으며, 발열량도 크게 증가하였다. 또한, 자연발화 실험결과 전분의 양이 증가할수록 훈소 개시온도가 낮아지고, 연소형태는 모두 훈소였다. 자연발화 시험기 내부가 송풍상태일 때 보다 무풍상태로 실험하였을 경우 훈소 개시시간이 다소 빨라지고 있으며, 발열최고온도도 크게 나타났다.

• Plant Resources
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• 제8권3호
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• pp.217-224
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• 2005

We tested the hypothesis that alpine plants have special physiological and biochemical mechanisms in addition to their structural adaptation in order to survive under extreme conditions. The photosynthetic organs of Pinus pumila were used to examine the seasonal changes in sugar concentration, antioxidative enzyme, and lipid peroxidation. The concentrations of sucrose, glucose, fructose and reducing sugar were the highest in the leaves in April. But sugar contents in buds and inner barks did not respond sensitively on temperature change. Meanwhile superoxide dismutase (SOD) activity responded sensitively on the change of temperature and SOD in all tissues maintained high activity in April. Meanwhile anthocyanin content increased rapidly in June but the increase of anthocyanin content was not enough to prevent their tissues from the damage by the exposure of high temperature or other stress. In conclusion, under low temperature condition, P. pumila increased the concentration of soluble sugars and SOD activity in their tissues in order to overcome extreme environmental condition. But in summer, these stress defense system against high temperature might be disturbed slightly. This results in the increase of malondialdehyde (MDA) contents in three tissues by lipid peroxidation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계합동학술대회 논문집
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• pp.153-157
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• 2002

This paper deals with the relationships between MgO manufacturing condition and misfiring at low temperature. The characteristics of MgO are affected by substrate temperature and MgO deposition current. In this study. the. substrate temperature was varied from $100^{\circ}C$ to $200^{\circ}C$. And the MgO deposition current was varied from 5mA to 20mA. As a result. the misfiring at low temperature was decreased in the panels with substrate temperature $200^{\circ}C$ and MgO deposition current 5mA. These results may be explained that the higher substrate temperature and lower MgO deposition current makes the denser film formation.

• Journal of Forest and Environmental Science
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• 제34권1호
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• pp.61-65
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• 2018

To know if small changes in rearing water temperature and density affect the number of bacterial and fungal colonies in metamorphosed frogs, Dybowski's frog tadpoles were reared from Gosner 25-26 stages at either low ($1^{\circ}C$ low to ambient water temperature), ambient, or high ($1^{\circ}C$ high) water temperature (each 15 tadpoles in 20 L water) condition and at either low (10 tadpoles/20 L water), medium (20 tadpoles), or high (30 tadpoles) density condition. Immediately after metamorphosis, we sampled bacteria and fungi from skin, liver, and heart of six metamorphosed frogs, randomly selected for each treatment group. After separate incubation of bacteria and fungi on 3M Petrifilm plates, we counted the number of bacterial and fungal colonies appeared on the plates and compared the numbers among the temperature and density treatment groups. For temperature treatment, high-temperature group had fewer bacterial colonies, while low-temperature group had more fungal colonies than the other two groups. For density treatment, low-density group had fewer bacterial colonies than the other two groups, but the number of fungal colonies were not different among the groups. Our results suggest that small increased rearing water temperature and lowered rearing density could potentially reduce pathogens in farming frogs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.61-64
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• 1998

We have investigated the effects of ultraviolet (UV) light irradiation condition and imidization temperature for the generation of pretilt angle in nematic liquid crystal (NLC) on the two kinds of the polyimide (PI) surfaces. High pretilt angle of NLC is generated with oblique p-polarized UV light irradiation of 30$^{\circ}$ on PI surface for 20 min. Also, the high pretilt angle of NLC is generated with oblique p-polarized UV light irradiation of 10-30$^{\circ}$ on PI surface at 20min. The pretilt angle of NLC decreases with increasing the imidization temperature on all rubbed PI surfaces ; the pretilt angle of NLC with oblique p-polarized UV light irradiation of 30$^{\circ}$on PI surface decreases with increasing the imidization temperature. The high pretilt angle of NLC is observed due to high photo-depolymerization reaction by low surface energy at low imidization temperature. We suggest that the pretilt angle of NLC is strongly attributed to the photo-depolymerization reaction with the UV light irradiation condition and imidization temperature.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.155-160
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• 2001

The low NOx characteristics have been investigated to develop the combustor for micro turbine. The lean premixed combustion technology was applied to reduce the NOx emission. The test was conducted at the condition of high temperature and ambient pressure. The combustion air which has the temperature of $450\sim650K$ were supplied to the combustor through the air preheater. The temperature and emissions of NOx and CO were measured at the exit of combustor, The exit temperature and NOx were increased and CO was decreased with increasing inlet air temperature. The premixing chamber can be operated very lean condition of equivalence ratio around 0.35. The NOx was decreased with decreasing the equivalence ratio. The CO was decreased with decreasing the equivalence ratio, but the CO was increased with decreasing the equivalence ratio below 0.4. But, at the very lean condition of equivalence ratio below 0.35 both NOx and CO were increased because of the flame unstability. The NOx was decreased and CO was increased with increasing inlet air flowrate. This results can be used to determine the size of combustor. Consequently the performance of combustor shows the possibility of the application to the gas turbine system.