• 제목/요약/키워드: peak factors

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Performance Factors for Delaying Slope Failure through Hydraulic Experiments of Dam Overtopping (댐 월류 수리실험을 통한 사면붕괴지연 성능인자 도출)

  • Sung Woo, Lee;Dong Hyun Kim;Seung Oh Lee
    • Journal of Korean Society of Disaster and Security
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    • v.17 no.2
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    • pp.1-11
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    • 2024
  • Most reservoirs in South Korea are earthen dams, mainly because they are cost-effective and easy to construct. However, earthen dams are highly vulnerable to seepage and overtopping, making them prone to sudden failure during excessive flooding. Such sudden failures can lead to a rapid increase in flood discharge, causing significant damage to downstream rivers and inhabited areas. This study investigates the effect of riprap placement on the slopes of earthen dams in delaying dam failure. Delaying the failure time is crucial as it allows more time for evacuation, significantly reducing potential casualties, which is essential from a disaster response perspective. Hydraulic experiments were conducted in a straight channel, using two different sizes of riprap for protection. Unlike previous studies, these experiments were performed under unsteady flow conditions to reflect the impact of rising water levels inside the dam. The target dam for the study was a cofferdam installed in a diversion tunnel. Experimental results indicated that the presence of riprap protection effectively prevented slope failure under the tested conditions. Without riprap protection, increasing the size of the riprap delayed the failure time. This delay can reduce peak discharge, mitigating damage downstream of the dam. Furthermore, these findings can serve as critical reference material for establishing emergency action plans (EAP) for reservoir failure.

Basic Studies on the Consumptive Use of Water Required for Dry Field Crops -Tomato and Chinese Cabbage- (밭작물소비수량에 관한 기초적 연구 -토마토 및 가을배추-)

  • 김철기;김진한;최홍규
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.30 no.3
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    • pp.25-37
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    • 1988
  • The purpose of this study is to fmd out the bask data for irrigation plans of tomato and chinese cabbage during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration, the maximum evapotranspiration, optimum irrigation point, total readily available moisture and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soji texture for split plot, and three levels, irrigation points with PF 1.8, PF 2.2, PF 2.6 for tomato and those with PF 1.9, PF 2.3, PF 2.7, for Chinese cabbage, soil textures of silty clay, sandy loam and sandy soil for both tomato and Chinese cabbage, with two replications. The results obtained are summarized as follows 1. There was the highest significant correlation between the evapotranspiration and the pan evaporation, beyond all other meteoralogical factors considered. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2. 1/10 probability values of maximum total pan evaporation during growing period for tomato and Chinese cabbage were shown as 355.8 mm and 233.0 mm, respectively, and those of maximum ten day pan evaporation for tomato and Chinese cabbage, 68.0 mm and 43.8 mm, respectively. 3. The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage of growing period for tomato, and at any growth stage till the late of Septemberfor Chinese cabbage. 4. The magnitude of evapotranspiration and of its coefficient for tomato and Chinese cabbage was occurred in the order of pF 1.8>pF 2.2>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7 respectively in aspect of irrigation point and of silty clay>sandy loam>sandy soil in aspect of soil texture. 5. 1/10 probability value of evapotranspiration and its coefficient during the growing period of tomato were shown as 327.3 mm and 0.92 respectively, while those of Chinese cabbage, 261.0 mm and 1.12 respectively. 6. The time that maximum evapotranspiration of tomato can be occurred is at the date of fortieth to fiftieth after transplanting and the time for Chinese cabbage is presumed to he in the late of septemben At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for tomato is presumed to be 74.8 mm and 1.10 respectively, while those of Chinese cabbage, 43.8 mm and 1.00. 7. In aspect of only irrigaton point, the weight of raw tomato and Chinese cabbage were mcreased in the order of pF 2.2>pF 1.8>pF 2.6 and of pF 1.9>pF 2.3>pF 2.7, respectively but optimum irrigation point for tomato and Chinese cabbage, is presumed to be pF 2.6 - 2.7 if nonsignificance of the yield between the different irrigation treatments, economy of water, and reduction in labour of irrigaion are synthetically considered. 8. The soil moisture extraction patterns of tomato and Chinese cabbage have shown that maximum extraction rate exists at 7 cm deep layer at the beginning stage of growth m any soil texture and that extraction rates of 21 cm to 35 cm deep layer are increased as getting closer to the late stage of growth. And especially the extraction rates of 21 cm deep layer and 35 cm deep layer have shown tendency to be more increased in silty clay than in any other soils. 9. As optimum irrigation point is presumed to be pF Z6-2.7, total readily available moisture of tomato in silty clay, sandy loam and sandy sofl becomes to be 19.06 mm, 21.37 mm and 20.91 mm respectively while that of Chinese cabbage, 18.51 mm, 20.27 mm, 21.11 mm respectively. 10. On the basis of optimum irrigation point with pF 2.6 - 2.7 the intervals of irrigation date of tomato and Chinese cabbage at the growth stage of maximum consumptive use become to be three days and five days respectively.

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The Cultural Landscapes of Wuyi-Gugok of China as seen from the 「Landscape of the Jiuqu River in the Wuyi Mountain」 in British Library (대영도서관 소장 「무이산구곡계전도(武夷山九曲溪全圖)」로 본 중국 무이구곡의 문화경관상)

  • Cheng, Zhao-Xia;Rho, Jae-Hyun;Jiang, Cheng
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.4
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    • pp.11-31
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    • 2019
  • Taking the painting, 「Landscape of the Jiuqu River in the Wuyi Mountain」 as the study object, which was produced in the middle of Qing Dinasty and collected by the British Library, this paper analyzes the scenery names recorded in the painting, and describes the landscape of the mountain, port and ships, architectural elements, civil elements, character, stone inscription and other scenery in the painting. The investigation results of the cultural landscape properties of each Gok are as follows: According to statistics, there are 28 architectural elements in the painting, including 7 pavilions (25%), 4 temples (14.3%), 3 Colleges and Taoist temple (10.7%), 2 Dowon(道院) and villages (7.1%); 29 civil elements, including 9 holes (31%), 6 Historical Sites (20.7%), 3 Stations(臺) (10.3%), 2 Ferries, 2 Bridges, and 2 Ponds (6.9%), 1 Garden, 1 Gate, 1 Mine(坑), 1 Well and 1 Remains(3.4%). These physical factors and civil factors are the important relics reflected the cultural landscape attributes of Wuyi-Gugok in the middle of the 18th century. Among the shape element in each Gok, the 1st Gok have 12 shape elements(21.1%), the 5th Gok 11(19.3%), the 4th Gok 9(15.8%), the 9th Gok 8(14%), the 3rd Gok 7(12.3%), the 6th Gok 4(7%), the 2nd Gok 3(5.3%), the 7th Gok 2(3.5%), and the 8th Gok 1(2%). Through collation, it is found that the 1st Gok, 5th Gok and 4th Gok have more prominent cultural landscape characteristics. In addition, according to the description of scenic spot types in 『Muisanji(武夷山志)』, there are 38 types of scenery description in the painting, of which, the three scenery of big rock, peak, small rock occupy the vast majority. This reflects the Danxia(丹霞) landform characteristics of Wuyi-Gugok. The cultural connotation of Wuyi Mountain expressed and contained in the painting is analyzed and interpreted, and it is found that the Jiuqu(九曲) River in the Wuyi Mountain has Neo-confucianism culture, Taoism culture, Buddhism culture, Tea culture and so on. In addition, among the 171 scenery names shown in the painting, there are altogether 7 stone inscriptions that are consistent with or have the same meaning as the rock inscriptions site, including 3 for inscriptions praising the landscape, 3 for philosophical inscription and 1 for auspicious language inscription, which is considered as the important basis for the mutual textuality between the pictures and the stone inscriptions.

Basic Studies on the Consumptive Use of Water Required for Dry Field Crops (2) -Garlic and Cucumber- (밭작물소비수량에 관한 기초적 연구(II)-마늘 및 오이-)

  • 김철기;김진한;정하우;최홍규;권영헌
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.31 no.3
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    • pp.41-56
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    • 1989
  • The purpose of this study is to find out the basic data for irrigation plans of garlic and cucumber during the growing period, such as total amount of evapotranspiration, coefficients of evapotranspiration at each growth stage, the peak stage of evapotranspiration and the maximum evapotranspiraton, optimum irrigation point, total readily available moisture, and intervals of irrigation date. The plots of experiment were arranged with split plot design which were composed of two factors, irrigation point for main plot and soil texture for split plot, and three levels ; irrigation points with pP 1.7-2.1, pP 2.2-2.5, pP 2.6-2.8, for garlic and those with pP 1.9, pF 2.3, pP 2.7, for cucumber, soil textures of silty clay, sandy loam and sandy soil for both garlic and cucumber, with two replications. The results obtained are summarized as follows 1.There was the highest significant correlation between the avapotranspiration of garlic and cucumber and the pan evaporation, beyond all other meteorological factors considered, as mentioned in the previous paper. Therefore, the pan evaporation is enough to be used as a meteorological index measuring the quantity of evapotranspiration. 2.1/10 probability values of maximum total pan evaporation during growing period for garlic and cucumber were shown as 495.8mm and 406.8mm, respectively, and those of maximum ten day pan evaporation for garlic and cucumber, 63.8mm and 69.7mm, respectively. 3.The time that annual maximum of ten day pan evaporation can be occurred, exists at any stage between the middle of May and the late of June(harvest period) for garlic, and at any stage of growing period for cucumber. 4.The magnitude of evapotranspiration and of its coefficient for garlic and cucumber was occurred in the order of pF 1.7-2.1>pF 2.2-2.5>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF2.7 respectively in aspect of irrigation point and of sandy loam>silty clay>sandy soil in aspect of soil texture for both garlic and cucumber. 5.The magnitude of leaf area index was shown in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 for garlic and of pF 1.9>pF 2.3>pF 2.7 for cucumber in aspect of irrigation point, and of sandy loam>sandy soil>silty clay in aspect of soil texture for both garlic and cucumber. 6.1/10 probability value of evapotranspiration and its coefficient during the growing period for garlic were shown as 391.7mm and 0.79 respectively, while those of cucumber, 423.lmm and 1.04 respectively. 7.The time the maximum evapotranspiration of garlic can be occurred is at the date of thirtieth before harvest period and the time for cucumber is presumed to be at the date of sixtieth to seventieth after transplanting, At that time, 1/10 probability value of ten day evapotranspiration and its coefficient for garlic is presumed to be 65.lmm and 1.02 respectively, while those of cucumber, 94.8mm and 1.36 respectively. 8.In aspect of irrigation point, the weight of raw garlic and cucumber were increased in the order of pF 2.2-2.5>pF 1.7-2.1>pF 2.6-2.8 and of pF 1.9>pF 2.3>pF 2.7 respectively. Therefore, optimum irrigation point for garlic and cucumber is presumed to be pF 2.2-2.5 and pF 1.9 respectively, when the significance of yield between the different irrigation treatments is considered. 9.Except the mulching period of garlic that soil moisture extraction patterns were about the same, those of garlic and cucumber have shown that maximum extraction rate exists at 7cm deep layer at the beginning stage after removing mulching for garlic and at the beginning stage of growth for cucumber and that extraction rates of 21cm to 35cm deep layer are increased as getting closer to the late stage of growth. 10.Total readily available moisture of garlic in silty clay, sandy loam, sandy soil become to be 18.71-24.96mm, 19.08-25.43mm, 10.35- 13.80mm respctively on the basis of the optimum irrigation point with pF 2.2-2.5, while that of cucumber, 11.8lmm, 12.03mm, 6.39mm respectively on the basis of the optimum irrigation point with pF 1.9. 11.The intervals of irrigation date of garlic and cucumber at the growth stage of maximum consumptive use become to be about three and a half days and one and a half days respectively, on the basis of each optimum irrgation point.

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Factors for persistent growth hormone deficiency in young adults with childhood onset growth hormone deficiency (소아청소년기 성장호르몬결핍증의 성인기 지속에 영향을 미치는 요인)

  • Lee, Young Ah;Chung, Hye Rim;Lee, Se Min;Kim, Jae Hyun;Kim, Ji Hyun;Lee, Sun Hee;Shin, Choong Ho;Yang, Sei Won
    • Clinical and Experimental Pediatrics
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    • v.52 no.2
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    • pp.227-233
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    • 2009
  • Purpose : Growth hormone (GH) replacement after retesting is necessary because impairment of body composition and cardiovascular health has been more severe in adult patients with persistent GH deficiency (GHD) from childhood to adulthood. This study aimed to investigate the factors for persistent GHD and define a highly probable group of persistent GHD in young adults with childhood-onset GHD. Methods : GHD was reassessed by insulin tolerance test (ITT) in 55 adult patients (39 males, 16 females) with childhood-onset GHD. Twelve patients presented with idiopathic GHD and 43 patients presented with organic GHD caused by tumors involving the hypothalamus-pituitary (H-P) region (n=33), other brain tumors (n=3), meningitis (n=3), leukemia (n=2) and others (n=2). Results : Forty-nine (89.1%) of 55 patients had persistent GHD. IGF-I was positively correlated with log of peak GH (r=0.57, P<0.001). There was no difference in the proportion of persistent GHD between idiopathic and organic GHD. The percentage of patients with persistent GHD was 40%, 80%, and 95.6% for patients with zero, one, two or more additional pituitary hormone deficiencies (PHDs), respectively (P=0.002). The probability of persistent GHD was higher in patients with diseases involving the H-P region (P=0.003). GHD persisted in 15 of 18 patients treated with cranial irradiation. Conclusion : We suggest that the probability of persistent GHD in adulthood was high in patients with 2 or more additional PHDs, and diseases involving the H-P region.

Effects of Stressful Life Events on Patients with Recurrent Ahthous Ulcer. (SRRS를 이용한 재발성 아프타성 구내궤양 환자의 생활변화에 관한 연구)

  • Ko, Myung-Yun;Kim, Young-Ae;Ok, Soo-Min;Heo, Jun-Young;Jeong, Sung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.37 no.4
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    • pp.195-203
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    • 2012
  • Recurrent aphthous ulcer(RAU) is the most frequent form of oral ulceration with a prevalence in the general population ranging between 5% and 60%. The peak age of onset is between 10 and 19 years of age, and it can persist into adulthood and throughout the patient's lifespan, with no gender predilection. The disease is characterized clinically into three types: minor aphthous ulcer, major aphthous ulcer and herpeticform ulcers. The cause of RAU is unknown and thought to be multifactorial with many triggers or precipitating factors that include familial tendency or genetic predisposition, allergy, medications, hormones, stress or anxiety, and immunologic abnormalities. The need for consideration of psychological factors in the pathogenesis of oral disease has been increasingly acknowledged over the last decades and many studies have highlighted the psycho-social impact of oral conditions. In this study, we tried to evaluate the influence of emotional stress in RAU. There were thirty patients with a clinical diagnosis of RAU and other subjects who did not show any signs of systemic disorders include RAU. They are evaluated by using modified Holmes and Rahe's Social Readjustment Rating Scale (SRRS). As a result, a significantly higher level of stress was found in the RAU patients than the control group. Therefore it can be concluded that psychological stressors play an important role in the RAU.

Environmental Factors Affecting the Start and End of Cicadae Calling - The Case Study of Hyalessa fuscata and Cryptotympana atrata - (매미과 울음 시작 및 종료에 영향을 미치는 환경요인 - 참매미, 말매미를 대상으로 -)

  • Kim, Yoon-Jae;Ki, Kyong-Seok
    • Korean Journal of Environment and Ecology
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    • v.32 no.3
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    • pp.342-350
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    • 2018
  • The purpose of this study was to identify the environmental factors that affect the beginning and end of calling by Hyalessa fuscata and Cryptotympana atrata, which are dominant cicada species in the central urban areas of Korea. The study area was Banpo Apartments in Seoul. The research period included two months, being from the end of July to the end of August 2015. We analyzed the start and end time of cicada calling, and on average H. fuscata started calling at 5:21 am and C. atrata started at 7:40 am. The average end time of calling was 6:31 pm for H. fuscata and 7:51 pm for C. atrata. From the scatter plot and box plot results, H. fuscata started calling at 05:00 am, whereas C. atrata consistently stopped calling at 20:00 pm compared to H. fuscata. Multiple regression analysis of the start and end time of cicada calling showed that sunrise time was a factor affecting the start of H. fuscata calling. The end time of H. fuscata calling was affected by sunset time and total cloud cover. The starting time of C. atrata calling was mostly affected by temperature and sunrise time. The effect of temperature was greater than that of sunrise time. The end time of C. atrata calling was strongly affected by sunset time, whereas peak temperature was also shown to affect the end time. From the above results, sunrise and sunset are thought to be the critical factor affecting the start and end time of H. fuscata calling. Therefore, H. fuscata started calling with sunrise, and the end time was also affected by sunset. Temperature was the factor most affecting the start of C. atrata calling and sunset was identified as the factor affecting the end time. Therefore, the start time of C. atrata calling shows variation with daily temperature changes, and C. atrata stop calling simultaneously with sunset.

Adenocarcinoma of the Uterine Cervix (자궁경부선암의 방사선 치료)

  • Chung Eun Ji;Shin Hyun Soo;Lee Hyung Sik;Kim Gwi Eon;Loh John Juhn-Kyu;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.9 no.2
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    • pp.277-284
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    • 1991
  • Survival data, prognostic factors, and patterns of failure were retrospectively analyzed for a total of 76 patients with adenocarcinoma of the uterine cervix treated between January 1981 and December 1987, which represents $4.1\%$ of all primary cervical carcinomas treated, at Department of Radiation Oncology, Yensei Cancer Center, Yonsei University College of Medicine. The mean age of the patients was 49 years (range, $27\~79$ years) and the peak incidence was in the group 50 to 59 years of age. More half of the patients were postmenopausal (46/76= $60.5\%$). Most patients ($76\%$) had abnormal vaginal bleeding either alone or in combination with other symptoms. The proportion of stage IIb was $43.4\%$. There were 4 major histologic subtypes: pure adenocarcinoma (48/76=$63.2\%$), adenosquamous carcinoma (20/76=$26.3\%$), papillary (5/76=$6.6\%$) and clear cell carcinoma (3/76=$3.9\%$). Of the many clinicopathologic variables evaluated for prognosis, the most significant prognostic factors were stage of disease and the size of tumor. The overall 5-year survival rate was $68\%$, and the 5-year survival rates for stage Ib, II and III were $90\%,\;66\%\;and\;54\%$, respectively. Control of pelvic tumors was achieved in $93.8\%,\;90.2\%\;and\;50.0\%$ of cases of stage Ib, II and III disease, respectively. In present study, treatment modalities (radiation therapy alone/combined operative and radiation therapy) did not affect the local control of tumor and the survival.

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Seasonal Variations of Nitrifying Bacteria in Agricultural Reservoir (농업용 저수지에서의 질화세균의 계절적인 변화)

  • Lee, Hee-Soon;Lee, Young-Ok
    • Korean Journal of Ecology and Environment
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    • v.35 no.3 s.99
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    • pp.152-159
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    • 2002
  • The seasonal variations of nitrifying bacterial population sampled from 3 sites in Moon-Chon reservoir were analyzed by in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes from August 2000 until July 2001. In addition, physico-chemical parameters such as temperature, pH, chi-a and DOC were measured to determine correlations between those factors and the size of nitrifying bacterial populations. Total bacterial numbers varied in the range of $0.8{\sim}1.5{\times}10^6\;cells/ml$ independent of sites and had the maximal values in March at all 3 stations. The ratio of eubacteria to total bacteria ranged from 44.9% to 79.5%, and the ratio of each nitrifying bacteria to eubacterial numbers reached only $1.0{\sim}7.4%$. The variations of ammonia-oxidizing bacteria ranged from $1.1{\times}10^4$ to $3.0{\times}10^4\;cells/ml$ without noticeable peak values whereas those of nitrite-oxidizing bacteria varied in $1.3{\sim}5.7{\times}10^4\;cells/ml$ with the increasing tendency in winter regardless of the sites. Moreover it was observed that the numbers of nitrite-oxidizing bacteria were higher than those of ammonia-oxidizing bacteria. Total bacterial numbers correlated with water temperature (r = 0.355, p<0.05) and DOC (r = 0.58G, p<0.01) positively whereas nitrite-oxidizing bacteria correlated with temperature (r = -0.416, p<0.05) and pH (r = -0.568, p = 0.001) negatively. In addition, DOC represented good correlations with eubacterial numbers (r = 0.448, p<0.01). These results indicate that temperature, DOC and pH might be one of the main factors affecting variations of bacterial populations in the aquatic ecosystem. It was also suggested that FISH method is a useful tool for detection of slow growing nitrifying bacteria.

Optimization of sterilization conditions for the production of retorted steamed egg using response surface methodology (반응표면분석을 이용한 레토르트 계란찜의 살균조건 최적화)

  • Cheigh, Chan-Ick;Mun, Ji-Hye;Chung, Myong-Soo
    • Korean Journal of Food Science and Technology
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    • v.50 no.3
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    • pp.331-338
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    • 2018
  • The purpose of this study was to determine the optimum sterilization conditions for the production of retorted steamed egg using response surface methodology. Sterilization processes for eighteen conditions using varying sterilization temperature ($X_1$), time ($X_2$), and method ($X_3$) as the independent variables were carried out through a $3^2{\times}2$ experimental factorial design. Quality evaluations after sterilization included measurements of $F_0$ value ($Y_1$), peak stress ($Y_2$), pH ($Y_3$), color value ($Y_{4-6}$), and organoleptic test [preference for appearance ($Y_7$), overall acceptability ($Y_8$), and preference for texture ($Y_9$) and egg taste ($Y_{10}$)]. Dependent variables ($Y_{1-10}$) of eighteen conditions were more affected by temperature and time than by the sterilization method. Eight factors were selected among the dependent variables as significant factors related to the quality of the steamed egg. Finally, by establishing an optimum range of each dependent variable and contour analysis, the optimum sterilization conditions for the production of steamed egg were determined to be $120^{\circ}C$ for 25 min using a 2-step sterilization process.