• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.61-65
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• 2010

초저온 추진제를 사용하는 액체로켓용 인젝터의 개발을 위해서는 단일 인젝터의 수류/연소시험을 통해 인젝터의 수력학적 특성 및 혼합, 미립화 등의 분무특성에 대한 연구가 필수적이다. 본 연구에서는 대학실험실 급에서 운용할 수 있는 범위의 가압식 초저온 추진제 공급장치 및 LabVIEW를 이용한 Cyclogram 제어 및 데이터 수집장치 등을 구축하였다. 제작된 시험장치를 이용하여 스월-동축인젝터의 $LN_2-GN_2$ 초저온 수류시험 및 분무 가시화를 수행하였다. 또한 LOX-$GCH_4$ 추진제 조합의 연소시험을 위한 연소기와 추력대를 설계 및 제작하였다.

• Restorative Dentistry and Endodontics
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• 제39권1호
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• pp.68-73
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• 2014

When a tooth shows discoloration and does not respond to the cold test or electric pulp test (EPT) after a traumatic injury, its diagnosis can be even more difficult due to the lack of proper diagnostic methods to evaluate its vitality. In these case reports, we hope to demonstrate that ultrasound Doppler might be successfully used to evaluate the vitality of the tooth after trauma, and help reduce unnecessary endodontic treatments. In all three of the present cases, the teeth were discolored after traumatic injuries and showed negative responses to the cold test and EPT. However, they showed distinctive vital reactions in the ultrasound Doppler test during the whole observation period. In the first case, the tooth color returned to normal, and the tooth showed a positive response to the cold test and EPT at 10 wk after the injury. In the second case, the tooth color had returned to its normal shade at 10 wk after the traumatic injury but remained insensitive to the cold test and EPT. In the third case, the discoloration was successfully treated with vital tooth bleaching.

• 한국해양공학회지
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• 제21권2호
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• pp.60-66
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• 2007

The first Korean cold room facility for ice mechanics experiments was assembled in 2004. Since then, the $4m{\times}6m$ cold room facility has been used, extensively under various environmental and loading conditions. After reviewing published references on cold room testing methods and also by trial and error, the standard procedures for testing and preparing laboratory ice material were established for the measurement of basic ice properties. In this paper, laboratory experimental techniques with the cold room facility and standard procedures established for ice material properties are introduced. Test specimens include laboratory-grown fresh water ice and frozen soils. Tests are carried out for unconfined compressive strength. Preparation and dimension of the specimen are the most important issues arising in cold room tests. The details of specimen preparation, testing procedure and strength test results are also discussed.

• 대한한의진단학회지
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• 제12권1호
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• pp.131-141
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• 2008

Background: In relation to a diagnosis of Korean Medicine, heat-cold is one of the most important indicators for evaluation. In spite of this importance, there has not been the study that tries to examine the change of indicators in an electrogastrography (EGG) according to the heat-cold patternization. Objective: The objective of this study is to establish the correlation between the heat-cold patternization and indicators of EGG by means of Standardized Questionnaire for Heat-Cold Patternization. Method: To conduct this study, we used the method as follows: Before conducting EGG, subjects were requested to give answers to the questionnaire which was developed by Kim. Before EGG, subjects were demanded to fast for more than 8 hours and then eat the test meal. Before eating the test meal(test meal: two slices of bread, 4oz of apple juice), EGG signals were detected for 30 minutes, and then subjects could eat the test meal for 10 minutes. After eating the test meal, EGG signals were detected for 30 minutes. Results: 1. There was a negative correlation between heat score and the power ratio of channel 1 and channel 2 of EGG. There was a positive correlation between cold score and the power ratio of channel 1 of EGG. 2. There was a positive correlation between heat score and pre-prandial gastric arrhythmia in the channel 1, 2 and 4 of EGG. There was a negative correlation between cold score and post-prandial gastric arrhythmia in the channel 1, 2 and 3 of EGG. 3. There was a negative correlation between heat score and normal pre-prandial gastric slow wave in the channel 1, 2 and 4 of EGG. There was a positive correlation between cold score and normal post-prandial gastric slow wave in the channel 3 of EGG. Conclusions: From the results above, we could conclude as follows: Indicators of EGG and cold score presented a positive correlation, and heat score displayed a negative correlation. As a result, to apply EGG to a diagnosis of functional indigestion, the application of EGG to subjects who have heat patternization would increase the reliability of a diagnosis.

• 한국작물학회지
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• 제34권2호
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• pp.134-141
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• 1989

보리종실의 샐리적 특성을 포장출아력과 비교함으로써 포장유묘출아율과 수량의 예측에 적합한 검정방법을 구명하고자 맥주보리 2품종과 쌀보리 2품종을 인위노화처리시켜 고온발아검정(warm germination test), 저온발아검정(cold germination test), Tetrazolium 유모세검정(TZ vigor test), 전기전도도검정(electroconductivity test)의 결과를 포장출아율 및 수량과 비교 검토 하였다. 고온발아검정과 저온발아검정이 포장출아율 예측에 효과적인 검정법으로 나타났으며, 이들의 관계는 맥주보리에서는 Y(포장출아율)=-2.962+0.229X$_1$ (% warm germination) -0.001X$_2$ (vigor, WGT) +0.354X$_3$ (vigor, CT) -0.558X$_4$ (% cold germination)으로 나타났다. 다중화귀방정식의 결정계수는 맥주보리의 경우 고온발아검정에서의 발아율만으로 포장출아율을 64%예측할 수 있었다. 고온발아유묘세, 저온발아유묘세, 저온발아율은 각각 4, 7, 9%씩 결정계수를 높혔다. 네가지 검정치의 누가적 예측효율은 맥주보리에서 84%, 쌀보리 54%였다. 수량에서는 포장출아율에서 보다 맥주보리, 쌀보리 공히 예측효과가 낮게 나타났다.

• Steel and Composite Structures
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• 제27권5호
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• pp.545-554
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• 2018

This study presents a novel method of improving the strength and stiffness of cold-formed steel (CFS) beams. Flexural members are primary members in most of the structures. Hence, there is an urgent need in the CFS industry to look beyond the conventional CFS beam sections and develop novel techniques to address the severe local buckling problems that exist in CFS flexural members. The primary objective of this study was to develop new CFS composite beam sections with improved structural performance and economy. This paper presents an experimental study conducted on different CFS composite beams with simply supported end conditions under four point loading. Material properties and geometric imperfections of the models were measured. The test strengths of the models are compared with the design strengths predicted by using Australian/New Zealand Standard for cold-formed steel structures. Furthermore, to ensure high precision testing, a special testing rig was also developed for testing of long span beams. The description of test models, testing rig features and test results are presented here. For better interpretation of results, a comparison of the test results with a hot rolled section is also presented. The test results have shown that the proposed CFS composite beams are promising both in terms of better structural performance as well as economy.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.25-28
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• 2010

한국항공우주연구원에서는 30톤급 액체로켓엔진 연소기 개발 기술을 바탕으로 설계 제작된 75톤급 기술검증시제의 수류시험 및 점화시험을 수행하였다. 수류시험을 통해 시험설비 공급라인의 수력학적 특성 및 냉각 케로신 충전시간을 파악하였다. 수류시험 결과로 점화절차를 결정하여, 점화시험을 성공적으로 수행하였다. 점화시험을 통해 획득한 자료와 시험 기법은 향 후 연소시험을 위해 활용될 것이다.

• Journal of Nutrition and Health
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• 제36권8호
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• pp.859-869
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• 2003

The purpose of this study was to compare the effects of soup temperature on hunger, energy, and nutrient intake. The hot meal consisted of 400 g of hot beef-vegetable soup (75$^{\circ}C$), Yubu Chobap, Bulgogi, cucumber pickle and radish pickle. The cold meal component were the same as the hot meal except 300 g of water (8$^{\circ}C$) and boiled vegctables (100 g), instead of the hot beef-vegetable soup ot the hot meal. Thirst, core temperature and blood pressure were also measured before and after consumption the test meals in a within-subjects, repeated measures design. 30 women consumed 17% more kilocalories, 13% more protein and lipid and 16% more carbohydrate in the cold meal than in the hot meal. The core temperature at the end of the test meal was higher in the hot meal than in the cold meal. Energy and nutrient intake were inversely correlated with the hunger scores within 1 hour after the hot meal, however those are not related with each other in the cold meal. So hunger feeling might be disturbed in the cold meal. It is concluded that energy and nutrient consumptions were higher in the cold meal, partly because of the distrubed hunger feeling in the cold meal.

• Pediatric Infection and Vaccine
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• 제5권2호
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• pp.302-307
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• 1998

Hemolytic anemia due to cold agglutinin disease is a known complication of Mycoplasma pneumoniae infection but is rarely observed, particularly in children. A case of Mycoplasma pneumonia complicated with hemolytic anemia is presented. A 7 year-old girl was adimitted because of fever, cough, sputum and pale appearance. Chest X-ray showed pneumonic consolidation of Rt. upper lobe, lingular division. Laboratory studies disclosed the following values : Hb 5.3g/dL, Hct 11.1%, reticulocyte 2.9%, indirect Coombs test negative, direct Coombs test(monovalent) Anti-C3d positive, Anti-IgG negative, Anti-IgM negative, cold agglutinin titer 1 : 256, mycoplasma antibody titer 1 : 640, total bilirubin 1.0mg/dL. Initial PBS before wanning showed agglutination of red blood cells. The diagnosis of cold agglutinin hemolytic anemia complicating mycoplasma pneumonia was made. And treatment with roxithromycin, prednisolone and avoiding cold exposure was initiated, and complete recovery ensued. We report a case of cold agglutinin hemolytic anemia complicating mycoplasma pneumonia in children.

• 대한의용생체공학회:의공학회지
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• 제30권3호
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• pp.199-204
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• 2009

Iridium oxide films (IROFs) have been extensively studied as a material for electrical stimulation of neurons, as iridium oxide has higher charge storage capacity than other metal films. More recently, sputtered iridium oxide film (SIROF) has been studied, because it can be made more conveniently than activated iridium oxide film (AIROF). Typically, the SIROFs are grown at temperatures from 400 to 600 $^{\circ}C$. However, such high temperatures cannot be used when the iridium oxide (IrOx) film is to be deposited on a flexible polymer material, such as polyimide. In this paper, we show that we can still obtain excellent characteristics in SIROFs grown without heating (cold SIROF), by optimizing the growth conditions. We show that the oxygen flow rate is a critical parameter for controlling the surface properties of a cold SIROF. At an oxygen flow rate of 12 seem, the cold SIROF exhibited a charge storage capacity (CSC) of 60 mC/cm$^2$, which is comparable to or better than other published values for iridium oxide films including heated SIROFs. The film produced under these conditions also had the minimum impedance value of all cold SIROFs deposited for this study. A stability test and biocompatibility test also demonstrated the superiority of the optimized cold SIROF.