• Nuclear Engineering and Technology
• /
• 제53권11호
• /
• pp.3704-3710
• /
• 2021

The characteristics of the external radiation on the surface of the casks for spent nuclear fuel (SNF) storage by dry method are investigated for the case when the spatial distribution of SNF in the basket changes due to the destruction of the fuel rod claddings. The surface areas are determined, where the changes in fluxes of neutrons, produced by ²⁴⁴Cm actinide, and γ-quanta, produced by long-lived isotopes, are maximum in the result of the decrease in the height of the SNF area. Concrete (VSC-24) and metal (SC-21) casks are considered as examples. The procedure of periodic measurement of the dose rate of neutrons or γ-quanta at the specified points of the cask surface is proposed for identifying the fuel rod cladding destruction. Under normal operation, the decrease in the dose rate produced by neutrons as the function of SNF storage duration is determined by the half-life of ²⁴⁴Cm, and for γ-quanta - by the half-lives of long-lived SNF isotopes. Consequently, a stepwise change in the dose rate of neutrons or γ-quanta, detected by the measurements, as compared to the previous one, would indicate the destruction of the fuel rod claddings.

• 한국자원식물학회지
• /
• 제27권3호
• /
• pp.256-262
• /
• 2014

Viscum album var. coloratum (mistletoe) is considered as one of the endangered plant species in Korea. Our objective is to restore its population and multiplication of plant by ex situ method. In this research we explored the maximum germination (in vitro) of freshly harvested and stored seeds of mistletoe collected in different time intervals. Ex vitro germination after artificial inoculation on the branches of Prunus mume in different physiological conditions was also monitored. The research revealed that the lately harvested seeds (Feb. and March 2014) were superior over early harvested seeds (Nov. 2013 and Jan. 2014) of mistletoe due to the higher percentage of germination (above 93%). According to the data, it is also revealed that the survival and germination rate of mistletoe seeds decreased with the increase in storage duration. In ex vitro germination, the fluctuated temperature of a glass house in natural condition enhanced (four fold) the rate of germination on the branches of Prunus mume than the constant temperature condition in the glass house.

• 원예과학기술지
• /
• 제34권6호
• /
• pp.807-817
• /
• 2016

Many onion growers and researchers assert that differences in soil type, agricultural practices, weather, and duration of prolonged onion cultivation in a particular field could affect onion bulb quality. This study evaluates the bulb quality of onions grown in different regions and determines the correlations between bulb characteristics and postharvest loss during cold and ambient storage. Soil and onion bulbs were collected from fields in six onion growing regions in Korea, during the growing season of 2011-2012. The fresh weight, dry matter content, and carbon (C), sulfur and magnesium contents of the onion bulbs were significantly affected by the location in which they were grown. Bulbs grown in Muan had the greatest number of scales, thinnest scale thickness, and the highest total soluble solids (TSS) and total flavonoids (TF). Bulbs originating from Jecheon had the lowest pyruvic acid (PA), total phenolics and TF. Storage loss of bulbs from the different regions was similar in refrigerated storage, but differed in ambient temperature storage. Bulb fresh weight was positively correlated with scale thickness (r = 0.617) and cold storage loss (CSL; r = 0.398). Dry matter content was positively correlated with C (r = 0.958) and TF (r = 0.256) contents, while it was negatively correlated with CSL (r = -0.424). CSL was primarily affected by the fresh weight, as well as the dry matter, C, and PA contents of the bulbs, while ambient storage loss was primarily influenced by the amount of TSS.

• 한국농공학회논문집
• /
• 제54권6호
• /
• pp.39-44
• /
• 2012

Water supply capacity and operational capability in agricultural reservoirs are expressed differently in the limited storage due to seasonal and local variation of precipitation. Since agricultural water supply and demand basically assumes the uncertainty of hydrological phenomena, it is necessary to improve probabilistic approach for potential risk assessment of water supply capacity in reservoir for enhanced operational storage management. Here, it was introduced the irrigation vulnerability characteristic curves to represent the water supply capacity corresponding to probability distribution of the water demand from the paddy field and water supply in agricultural reservoir. Irrigation vulnerability probability was formulated using reliability analysis method based on water supply and demand probability distribution. The lower duration of irrigation vulnerability probability defined as the time period requiring intensive water management, and it will be considered to assessment tools as a risk mitigated water supply planning in decision making with a limited reservoir storage.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제50권1호
• /
• pp.15-22
• /
• 2001

In this paper, a VSC(Voltage Sag Corrector) is discussed for the purpose of power quality enhancement. A fast detecting technique of voltage sag is accomplished through the detection of instantaneous value on synchronous reference frame. A robust characteristic against the noise is available by inserting the first order low pass filter in the detection circuit. The formula and the filter design process is described properly with the mathematical equations. Because the VSC system supply the active power to load, it is required to design the proper size of the energy storage system, In this paper, the capacitor bank is used as an energy storage system, and the size of the capacitor is designed from the point of view of input/output energy as the output power rating and the amplitude and duration time of the voltage sag. The simulation is accomplished by PSCAD/EMTDC.

• Journal of Preventive Medicine and Public Health
• /
• 제31권4호
• /
• pp.708-718
• /
• 1998

To investigate the effect of smoking and drinking habit on the health status in lead using industries, 2,785 male workers in lead using industries (7 storage battery industries, 7 secondary smelting and related industries, and 4 primary metal and other manufacturing industries) were selected for this study. This study was carried out as a part of periodic health examination. Selected study variables were zinc protoporphyrin in whole blood (ZPP), SGOT and SGPT for laboratory test. Questionnaire for lead related symptoms and smoking and drinking habit was provided to all the workers and filled up by themselves and reconfirmed by physician. The results obtained were as follows; 1. The overall smoking and drinking rate of study population were 69.8% and 73.6%, respectively. While the smoking and drinking rate of storage battery workers were 68.8% and 72.3%, those of secondary smelting industries and other industries were 66.0% & 66.4% and 74.6 & 80.3% respectively. 2. While the mean values of blood ZPP of lead exposed workers were significantly higher than other group, those of SGOT of storage battery workers were significant higher than other worker. But there were no differences of mean values of other variables. 3. Smoking habit did not affect on the mean value of blood ZPP of workers in special health examination group, but there were significant differences of blood ZPP and SGOT between drinker and non-drinker. 4. Symptom prevalence of lead exposure were higher in drinking and smoking group than non-drinking and non-smoking group. 5. In multiple regression analysis of the total lead related symptoms, blood ZPP, SGOT, and SGPT as dependent variable, respectively, and age, work duration, blood ZPP, pack year and amount of alcohol drinking as independent variables, work duration, pack year, amount of alcohol drinking, age contributed to total symptoms; and age, work duration, pack year contributed to blood ZPP; and age, amount of alcohol drinking, work duration contributed to SGOT; and pack year contributed to SGPT.

• 한국작물학회지
• /
• 제32권2호
• /
• pp.137-143
• /
• 1987

단옥수수를 수확한 후 저장온도에 따라 맛을 유지할 수 있는 저장기간을 알아보기 위하여 보통단옥수수 2품종(Great Bell. Golden Cross Bantam)과 초당옥수수(Crisp Super Sweet 720) 1 품종을 공시하여 출사 후 20일과 25일에 수확하였다. 저장온도는 냉동(영하 2$0^{\circ}C$), 0, 5. 10, 15, 20, $25^{\circ}C$C이었고 저장기간은 1, 3, 5. 7일이었으며 저장온도와 기간에 따른 가용성 고형물, 당함량, 맛의 노화 및 이들 상호간의 관계를 조사하였으며 그 결과를 요약하면 다음과 같다. 1. 가용성 고형물은 1$0^{\circ}C$이하에서는 크게 변하지 않았으나 15$^{\circ}C$ 이상에서는 저장기간이 길어질수록 현저히 감소하였다. 2. 전당함양은 1$0^{\circ}C$ 이하에서는 감소가 적었으나 15$^{\circ}C$ 이상에서는 저장기간이 길어질수록 급격히 감소하였는데 fructose와 glucose보다는 수확시 함량이 많았던 sucrose가 주로 감소하였다. 3. 맛은 냉동저장하면 크게 저하되지 않으나 $0^{\circ}C$에 저장한 것보다 좋지 않았다. 맛을 유지할 수 있는 저장기간은 1$0^{\circ}C$ 이하에서는 7일, 15$^{\circ}C$에서는 3일, $25^{\circ}C$에서는 1~2일이었다. 4. 가용성 고형물과 맛, 전당함량과 맛과는 모두 정의 상관이 있었다.

• 한국축산식품학회지
• /
• 제37권3호
• /
• pp.440-448
• /
• 2017

This study was conducted to establish the shelf life of $1^{++}$ grade Hanwoo beef by evaluating the changes in meat quality and storage stability under distribution conditions similar to those during export to Hong Kong and China. Four muscles of the loin, striploin, tenderloin, and top round muscles were obtained from 10 animals of $1^{++}$ grade Hanwoo steers. The distribution conditions were 0, 7, or 14 d of aging at $2^{\circ}C$ and continuous storage at $-18^{\circ}C$ for 0, 3, 6, or 9 mon. The lightness (CIE $L^*$) values decreased as the duration of freezer storage increased (p<0.05). The water-holding capacity of 4 muscles increased as the aging time increased when they were frozen for 3 mon (p<0.05). The cooking loss values of the four muscles were significantly increased as the duration of freezer storage increased (p<0.05). The Warner-Bratzler shear force values were significantly decreased in the loin, striploin, and top round muscles as the aging time increased (p<0.05). The changes in volatile basic nitrogen (16.67-18.49 mg%) and thiobarbituric reactive substance values (0.75-0.82 mg MA/kg meat) were significantly increased when the meat was frozen for 9 mon after 14 d of aging. On the basis of these observations, the shelf life of $1^{++}$ grade Hanwoo beef during distribution should be limited to less than 9 mon of freezer storage at $-18^{\circ}C$ after 14 d of aging at $2^{\circ}C$.

• 한국방재학회 논문집
• /
• 제5권2호
• /
• pp.17-28
• /
• 2005

본 연구의 목적은 소규모 유역에서 홍수 저류시설물과 홍수 조절시설물 사이의 임계지속기간을 평가하는데 있다. 4개 소규모 유역을 통하여 수문분석을 실시하였으며, 유효우량은 NRCS 유효우량 산정방법으로 산정하였다. 홍수 저류시설물과 홍수 조절시설물의 임계지속기간은 허용방류량 고정개념을 이용하여 평가하였다. 허용방류량 고정개념을 이용한 경우 최대 저류비를 발생시키는 시간분포는 Huff 2분위 시간분포로 나타났으며, 자연방류형 단일저류지에서 홍수 조절시설물의 임계지속기간은 홍수 저류시설물의 임계지속기간과 유사한 것으로 나타났다.

• 한국식품조리과학회지
• /
• 제30권4호
• /
• pp.444-453
• /
• 2014

$15^{\circ}Bx$ 흑마늘 추출액 1%에 울금(ST1), 백년초(ST2), 아스파라거스(ST3) 및 알로에(ST4) 분말을 각각 0.3%씩 첨가한 소시지를 제조하여 $8^{\circ}C$에서 4주간 저장하면서 품질 변화를 살펴보았다. 색도는 흑마늘 추출물이 첨가된 대조구에 비해 백년초 분말을 첨가한 ST2에서 명도, 적색도가 가장 높게 측정되었으며, 황색도는 아스파라거스 분말을 첨가한 ST3에서 높게 측정되었다. 전단가는 저장 0일에 대조구가 $854.19{\pm}38.21cm/kg^2$으로 가장 높게 측정이 되었다. 산도는 pH와 유사한 경향으로 ST4가 가장 높았으며 대부분의 처리구가 저장 2주까지 증가하다가 감소하는 경향이었다. 총당은 저장 0일에 ST4가 $17.46{\pm}0.92mg/100g$으로 가장 높은 함량이었으며 전체적으로 저장기간의 경과에 따라 증가하였다. TBARS 함량은 처리구가 대조구에 비해 낮아지는 경향을 보였으나 전체적으로 저장기간이 경과함에 따라 모든 시료에서 유의적으로 증가하였다. ABTS 라디칼 소거능은 $1000{\mu}g/mL$ 농도에서 저장 0일에 $89.11{\pm}0.66{\sim}99.22{\pm}0.09%$의 높은 소거능을 보였다. 결과적으로 화학적 및 물리적 특성 결과와 비교했을 시 흑마늘에 특화작물의 첨가가 상품화 가능성이 있는 것으로 판단되었다.