• Title/Summary/Keyword: 특성 손실

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A Case Study for the Determination of Time Distribution of Frequency Based Rainfall (확률강우의 적정시간분포 결정에 관한 연구)

  • Lee, Jeong Ki;Kim, Hung Soo;Kang, In Joo
    • Journal of Wetlands Research
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    • v.6 no.3
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    • pp.71-81
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    • 2004
  • In recent, the heavy rainfall is frequently occurred and the damage tends to be increased. So, more careful hydrologic analysis is required for the designs of the hydraulic or disaster prevention structures. The time distribution of a rainfall is one of the important factors for the estimation of peak flow in hydrologic and hydraulic designs. This study is to suggest a methodology for the estimation of a rainfall time distribution which can reflect the meteorologic and topographical characteristics of Daejeon area. We collect the 34 years' rainfall data recorded in the range of 1969 to 2002 for Daejeon area and we performed the rainfall analysis with the data in between May and October of each year. According to the Huff method, the collected data corresponds to the first quartile which the rainfall is concentrated in the primary stage but the suggested method shows the different rainfall distribution with the Huff method in time. The reason is that the Huff method determines the quartile in each storm event while the suggested one determines it by estimating the dimensionless distribution of rainfall in duration after the accumulation of rainfall in time. The rainfall distributions estimated by two methodologies were applied to the Gabcheon basin in Daejeon area for the estimation of flood flow. Here we use the SCS method for the effective rainfall and unit hydrograph for the flood discharge. As the results, the peak flow for 24-hour of 100-year frequency was estimated as a $3421.20m^3/sec$ by the Huff method and $3493.38m^3/sec$ by the suggested one. We can see the difference of $72.18m^3/sec$ in between two methods and thus we may carefully determine the rainfall time distribution and compute the effective rainfall for the estimation of the peak flow.

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A Study on Comparison of Outdoor Wind Pressure Performance According to Outdoor Exposure and Acceleration Deterioration Methods of Structural Sealants Applied to Curtain Wall (커튼월에 적용된 구조용 실링재의 옥외폭로와 실내복합열화 처리방법에 따른 내풍압성능 비교연구)

  • Jang, Pil Sung;Hong, Soon Gu;Kim, Sung Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.279-287
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    • 2018
  • Sealants are an important element of modern architecture and serve as a building protection against weathering by providing barriers against ingress of moisture, air, and other materials. Exposure to a variety of environments often reduces lifespan due to changes in physical, chemical and mechanical characteristics, and UV, humidity, and temperature expansion are important issues that are directly related to durability. In this study, a combined deterioration test chamber was developed to simulate the environment of the open air as an instrument for verifying the durability of structural sealing materials indoors. In order to replicate special weather conditions, such as yellow dust, acid rain, and contamination by microorganisms, it was deemed impossible to replicate the outdoor environment by 100 %, and the results of the results of the results of the external exposure test of the structural sealant and the combined deterioration testing device. As a result of the displacement test of the outdoor exposure test, it was determined that the sealant was breaking apart and that it would be smooth, and the displacement would be up to three times greater than the initial material value of 1 year. The displacement test results of the combined deterioration test device show the tendency to deteriorate, decreasing the elasticity and tensile characteristics. In the case of denatured silicon, the current 400 cycles have been completed to confirm 12 months of degradation of the external exposure. The deformation of the test specimen cannot be verified with the naked eye, so it is considered that the conditions of the specimen are more stable than the silicon sealant. As a result of the outdoor exposure test, if the combined deterioration test device is structured and proposed in the relevant guidance or specification, the anticipated lifespan of 12 months in the actual use environment can be verified indoors and below 3 months later, economically.

Effects of Membrane-filtered Powder of Sunmul on the Quality Characteristics of Noodles (막분리한 순물의 농축분말 첨가가 국수의 품질에 미치는 영향)

  • Chung, Hai-Jung;Choi, Min-Hee;Kim, Woo-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.199-204
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    • 2006
  • This study was conducted to investigate the quality characteristics of noodles prepared with the addition of nanofiltered (NF) powder of sunmul. Noodles were prepared with different levels $(0\%,\;1.5\%,\;3\%\;and\;5\%,\;w/w)$ of NF powder and physico-chemical properties were examined. Results of rapid visco analyzer showed that peak, trough, final viscosity and set back decreased as the NF powder level increased. The weight and volume of cooked noodles increased with the addition of NF powder. Turbidity of soup also increased as the amount of NF powder increased, indicating higher cooking loss. The color of wet and cooked noodles became greenish yellow as the NF powder level increased. Hardness, springiness, gumminess and brittleness of cooked noodles decreased with the increasing amount of NF powder. Results of sensory evaluation showed that noodles prepared with up to $3\%$ addition of NF powder was considered to be as acceptable as noodles prepared without NF powder.

Assessment of Dietitian's Nutritional Quality Management for School Food Service (학교급식 영양사의 영양적 품질관리 수행도 평가)

  • Ryu, Kyung;Woo, Chang-Nam;Kim, Woon-Ju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.238-247
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    • 2006
  • The purpose of this study was to evaluate school dieticians' performance of nutritional quality control, and further to establish effective and objective standards of nutritional quality control. Data for this study came from 200 school dieticians' responses in the Chungbuk area. The total quality management (TQM)-based questionnaire was structured. The questionnaire consisted of the following four fields (1) performance of nutritional quality control, (2) performance of stepwise food production to maximize nutrient preservation rate, (3) management of documents and records related to nutritional quality control, and (4) other relating matters. The items of the questionnaire were measured on a five-point Likert scale which ranged from 'strongly agree' to 'strongly disagree'. First, the analysis indicated that school dieticians performed 'least' on human resource management', 'mediocre' on nutritional quality control, and best on 'leadership'. Second, the analysis on performance of stepwise food production to maximize nutrient preservation rate showed that dieticians considerably endeavored to maximize nutrients of cooked food, but it was found out that the most of nutrient destruction can be caused by heating during cooking. Third, the result showed that the systematic use of documents and records for nutritional quality control was not sufficiently accomplished, especially in the production phase of food. In addition, the measure by the Pearson correlation coefficient indicated that there was a significant relationship between performance of nutritional quality control and performance of stepwise food production to maximize nutrient preservation rate, and between performance of nutritional quality control and management of documents and records related to nutritional quality control. Finally, the findings of this study suggest that more effort should be exerted to carefully establish TQM-based standards for the improvement of nutritionary quality.

A Study on the Quality Characteristics of the Bread with Samultang (사물탕을 첨가한 식빵의 품질 특성)

  • Oh, Hyun-Kyung;Shin, Mal-Shick;Lim, Hyeon-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.5
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    • pp.643-650
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    • 2007
  • It has been known that Samultang has positive effects on blood circulation and erythrocyte formation. Samultang was composed of four ingredients, Angelica gigas Nikai, Rahmanniae Radix Preparata, Paeonia lactiflora Pallas, and Cnidium officinale Makino. Five types of bread were prepared by replacing water with Samultang for dough proportionally. Control (C) did not have Samultang and the other four experimental bread contained Samultang: S-I (25% of water was substituted by Samultang), S-II (50% substituted), S-III (75% substituted), and S-IV (100% substituted). Moisture, protein, and ash contents of Samultang were $97.34{\pm}0.11%,\;0.42{\pm}0.04%,\;and\;1.40{\pm}0.16%$, respectively. Replacing water with Samultang decreased pH and increased significantly wet gluten content of the dough. Substitution of Samultang for water incremented redness and yellowness of the dough and bread and increased hardness. It also raised the contents of ash and protein. Although it was not significant, in addition, moisture loss of the bread during storage seemed to be lessened by replacing water with Samultang. However, total volume and specific loaf volume of the bread, baking loss rate, and the other textural characteristics except hardness were not affected by substituting water with Samultang. Due to the above results, sensory evaluation of volume and gumminess of the bread were improved significantly by substituting Samultang for water. The bread replaced 25% of the water with Samultang was ranked as the best by the test of sensory evaluation. These results imply that adding Samultang instead of water to dough for bread might bring positive effects on quality characteristics of the bread without any adverse influences. Therefore, it might be worth developing functional bread using Samultang.

Combination Effect of Various Freezing and Thawing Techniques on Quality and Nutritional Attributes of Onions (다양한 냉·해동 방법에 따른 양파의 이화학적 특성 및 영양성분 변화)

  • Jung, You-Kyoung;Jang, Min-Young;Hwang, In-Guk;Yoo, Seon-Mi;Min, Sang-Gi;Jo, Yeon-Ji;Chun, Ji-Yeon;Choi, Mi-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.10
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    • pp.1492-1503
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    • 2015
  • This study evaluated the combination effect of various freezing and thawing techniques on the quality and nutritional aspects of onions. Onions were frozen by natural air convection freezing (NCF), air blast freezing (ABF), and liquid nitrogen freezing (LNF). Onions were frozen for 76 min by NCF, 9 min by ABF, and 9 min by LNF. The freezing treatment was stopped when the core temperature reached $-12^{\circ}C$ for NCF and ABF, and $-120^{\circ}C$ for LNF. Frozen samples were thawed through natural air convection thawing, running water thawing, sonication thawing (ST), or microwave thawing. The quality and nutritional aspects of frozen-thawed onions were evaluated by measuring thawing loss, pH, texture, water content, color, and SEM image. ST was found to cause the least loss in onion sample among the tested thawing methods, whereas the freezing methods did not cause any significant loss. In our experiment, thawing is found to be a more critical technique when compared to that of freezing. There were no clear quantifications or trends of pH and water content among different freezing and thawing techniques. The highest total color difference (${\Delta}E$) was observed in the NCF sample. For morphological observation, ABF gave the smallest ice crystal size, as well as minimum cell collapse. Loss of vitamin C, free sugar, and organic acid content was lower in the ABF and ST sample, when compared to other trials. In our study, we found that combination of ABF and ST could preserve the quality and nutritional aspects of frozen-thawed onions better than other methods.

Quality Characteristics of Sponge Cake with Addition of Protease (단백질가수분해효소를 첨가한 스펀지케이크의 품질 특성)

  • Yoon, Seongjun;Cho, Namji;Moon, Sung-Won;Kim, Misook;Lee, Youngseung;Yoon, Ok Hyun;Jeong, Yoonhwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.5
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    • pp.761-766
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    • 2015
  • This study investigated the effect of protease on quality characteristics of sponge cake. Protease was used at levels of 0.0005 U (PC-1), 0.0010 U (PC-2), 0.0015 U (PC-3), and 0.0020 U (PC-4) for sponge cake preparation. Amylogram showed the setback was significantly decreased in comparison with the control (P<0.05). Height and baking loss rate of control sponge cake were $4.24{\pm}0.18cm$ and $12.01{\pm}0.29%$, respectively. PC-3 and PC-4 showed increased heights of $5.22{\pm}0.16$ and $5.24{\pm}0.11cm$ as well as slightly increased baking loss rates of $12.71{\pm}0.31%$ and $12.89{\pm}0.61%$, respectively. Specific volume and color difference measurements of control showed a specific volume of $3.53{\pm}0.06mL/g$, crust color difference of $53.05{\pm}0.28$, and crumb color difference of $29.84{\pm}0.52$. Measurements of specific volume, crust color, and crumb color of PC-3 and PC-4 were $4.18{\pm}0.02mL/g$, $56.19{\pm}0.84$, $29.05{\pm}0.43$, $4.21{\pm}0.02mL/g$, $56.85{\pm}0.43$, and $29.45{\pm}0.47$, respectively. Firmness measurements showed that the control had the highest firmness. PC-3 and PC-4 were effective at improving the shelf-life of sponge cake as indicated by reduced firmness. Sensory evaluation results demonstrated that all samples scored higher than the control. Throughout the results, the addition of protease increased volume and improved quality characteristics of sponge cake.

Quality Characteristics of Pound Cake with Addition of Cashew Nuts (캐슈를 첨가한 파운드케이크의 품질특성)

  • Choi, Soon-Nam;Chung, Nam-Yong
    • Korean journal of food and cookery science
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    • v.26 no.2
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    • pp.198-205
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    • 2010
  • In this study, the effect of added cashew nuts on the quality characteristics of pound cake were investigated. The weight and volume of the cake increased with the addition of cashew nuts concentration, whereas the dough yield and baking loss decreased. Furthermore, the hardness, penetration and, degree of retrogradation significantly decreased during storage with the addition of cashew nuts. As the cashew concentration was increased, the lightness and redness values of the crumb decreased and the yellowness values increased. In terms of sensory evaluation, when compared to the control group, the cashew nuts pound cake was superior in taste, flavor, chewiness and overall acceptability.

Genetic Variance and Combining Ability of Shattering and Growth Characters by Diallel Crosses of Sesame (이면교잡에 의한 참깨의 탈립성 및 생육형질의 유전변이와 조합능력)

  • Kim, Dong-Hwi;Kang, Chul-Whan;Shim, Kang-Bo;Park, Chang-Hwan;Lee, Sung-Woo;Seong, Nak-Sul
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.7
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    • pp.652-657
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    • 2006
  • Combining ability and heterosis for $F_{1}$ population obtained $5{\times}5$ half diallel cross in sesame were estimated for six quantitative characters. The parental varieties used for diallel cross were Yangbaek and Ansan of normal type, Suwon 177 and 195 of placenta adhesion type (PA) and SIG960320-5-1-1 of indehiscent type (ID). PA and ID type are shattering-resistant sesames and Yangbaek and Ansan are shattering sesames. The high heterosis of $F_{1}$ hybrids was expressed in the number of capsules per plant (NC), grain yield per plant (GY) and number of branches per plant (NB). Shattering.ate (SR) showed high positive heterosis toward increase of seeds shattering in all the combination of $F_{1}$ generation which was presumed because the characters connected with shattering resistance of seeds were governed by recessive gene. At the analysis of combining ability, highly significant general combining ability (GCA) effects were observed on all the characters in $F_{1}$ generation, significant specific combining ability (SCA) effects were observed on the NC, GY and SR. GCA variances were greater than SCA variance, which suggested that additive gene effects were greater than other nonadditive gene effects. Considering the estimated GCA effects, Suwon 195 (PA type) was found to be good parent for SR and GY, SIG960320-5-1-1 (ID type) was poor for GY and plant height. SCA effect for NC was great in Yangbaek/Suwon 195, SCA for GY was great in Ansan/SIG960320-5-1-1, and SCA for decrease of SR was great in Ansan/Suwon177.

Overview of Real-time Visibility System for Food (Livestock Products) Transportation Systems on HACCP Application and Systematization (축산물 유통단계의 HACCP 적용과 체계화를 위한 실시간 관제시스템에 대한 현황)

  • Kim, Hyoun-Wook;Lee, Joo-Yeon;Hong, Wan-Soo;Hwang, Sun-Min;Lee, Victor;Rhim, Seong-Ryul;Paik, Hyun-Dong
    • Food Science of Animal Resources
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    • v.30 no.6
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    • pp.896-904
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    • 2010
  • HACCP is a scientific and systematic program that identifies specific hazards and gives measurements in order to control them and ensure the safety of foods. Transportation of livestock and its products is one of the vulnerable sectors regarding food safety in Korea, as meats are transported by truck in the form of a carcass or packaged meat in a box. HACCP application and its acceleration of distribution, in particular transportation, are regarded as important to providing consumers with ultimately safe livestock products. To achieve this goal, practical tools for HACCP application should be developed. Supply chain management (SCM) is a holistic and strategic approach to demand, operations, procurement, and logistics process management. SCM has been beneficially applied to several industries, notably in vehicle manufacture and the retail trade. HACCP-based real-time visibility system using wireless application (WAP) of the livestock distribution is centralized management system that enables control of temperature and HACCP management in real-time for livestock transportation. Therefore, the application of HACCP to livestock distribution (transportation, storage, and sale) can be activated. Using this system, HACCP management can be made easier, and distribution of safe livestock products can be achieved.