• Title/Summary/Keyword: deterioration factor

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Induction Period and Oxidative Rancidity of Refrigerated Fish Meat (동결어육(凍結魚肉)의 유도기와(誘導期)와 산화(酸化))

  • Joe, Sang-June;Kim, Dong-Yun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.1
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    • pp.36-41
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    • 1987
  • In the refrigerated storages of fishery products, the lipid oxidation of the meats had been the major deterioration factor. For the effective utilization of mackerel, Scomber japonicus, and yellow corvenia, Pseudosciaena manchuria, which are major costal fish in Korea, and were studied about oxidative rancidity during the refrigerated storage at $-18^{\circ}C$ and the effect of different temperatures upon the cooked meat. We detected the results followed. 1. The Induction period of refrigerated storages had 20 days for fresh meat and 60 days for cooked meat. 2. Peroxide and TBA value of cooked meats had half amount values In the comparison with those of fresh meats, 3. Values of mackerel had double amount than those of yellow corvenia in peroxide and TBA value as if the different values come from different fish species, 4. The rancidative degree of the different temperatures on the samples had the least amount at $-5^{\circ}C$ among several kinds of storage temperatures.

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Influence of Sulfur Fertilization on Quality Characteristics and Antioxidant Activities of Onions during Storage at 4℃ (유황처리가 4℃ 저장 중 양파의 품질 특성 및 항산화 활성에 미치는 영향)

  • Jo, Hyeri;Surh, Jeonghee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.12
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    • pp.1776-1783
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    • 2016
  • Onions cultivated with (SY) or without (SN) sulfur application were stored for up to 36 weeks at $4^{\circ}C$ since harvest, after which they were analyzed for chemical composition and antioxidant activity in relation to sulfur (S) application and storage duration. Compared with SN onions, SY onions showed lower moisture and higher protein, soluble solids, and flavonoid contents at the time of harvest, and moisture and protein contents remained the same until 20 weeks of storage. However, soluble solids decreased while antioxidant activities, including flavonoids content, total reducing capacity, and superoxide dismutase (SOD)-like activity, appreciably increased as storage time increased to 20 weeks, which could be attributed to onion respiration and protective response to environmental stresses, respectively. There were abrupt decreases in flavonoid content and SOD-like activity at 36 weeks, presumably due to severe deterioration. Interestingly, all phenomena observed depending on storage time were independent of S application of onions. The results show that the critical factor influencing the chemical composition and antioxidant activity of onions during storage was postharvest storage duration rather than S application during onion cultivation.

Modified Atmosphere Storage for Extending Shelf Life of Oyster Mushroom and Shiitake (환경가스조절 저장방법을 이용한 느타리버섯과 표고버섯의 유통기간 연장)

  • Han, Dae-Seok;Ahn, Byung-Hak;Shin, Hyun-Kyung
    • Korean Journal of Food Science and Technology
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    • v.24 no.4
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    • pp.376-381
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    • 1992
  • In order to study the effect of modified atmosphere storage on extending shelf life of mushrooms, oyster mushroom and Shiitake were wrapped with polyethylene film (PE, $50\;{\mu}m$), and stored at $0.5^{\circ}C$. Mushrooms packed with conventional hardboard box (4kg) lost marketability within $5{\sim}6$ days due to weight loss, shrinkage, browning, spore formation and/or mycellium growth. PE-packing could prevent or retard the deterioration of the mushrooms in the aspects of appearance, texture, discoloration, and microbial contamination. This situation can be best characterized by the reduced respiration rate resulted from the elevated level of carbon dioxide and the reduced level of oxygen in the bag. Although the appearance of the oyster mushroom was maintained for one month, its shelf life was limited to 15 days because of tissue softening. Discoloration of the pileus of shiitake mushroom appears to be the most important factor to determine its marketability. For example, extension of shelf life of Dongo was limited to 15 days, principally due to the browning of the pileus. Shelf life of Hawgo whose color of the pileus changed little over the experimental period, however, could be extened to more than one month.

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Preservation of Noodles Adding the Wheat Flour Ferment Cultured by Lactobacillus acidophilus (Lactobacillus acidophilus를 배양한 밀가루 발효물이 면의 저장성에 미치는 영향)

  • Cha, Wook-Jin;Lee, Jeong-Hoon;Lee, Si-Kyung
    • Korean Journal of Food Science and Technology
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    • v.39 no.2
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    • pp.164-168
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    • 2007
  • The principal objective of this study was to determine the effects of wheat flour ferment cultured with Lactobacillus acidophilus, specifically with regard to the preservation of noodles. The results showed that the addition of ferment to wheat flour during noodle preparation reduced the pH of the noodles, and no significant difference was observed in the L and ${\Delta}E$ values of the noodles adding 5% ferment. Total bacterial levels were decreased in the wet noodles to which more than 10% ferment was added, by a factor of log $10^3$ as compared to the levels seen in the control during storage. Deterioration became apparent at 4 days of storage in regular wet noodles, but did not occur until 6 days in the wet noodles to which 5% ferment was added, and not until 8 days of storage in the noodles to which 10% ferment was added. Cooked noodles deteriorated at 8 days after the beginning of storage, but the addition of 5% and 10% ferment extended that time to 12 days and 14 days, respectively. It was concluded that flour ferment cultured with L. acidophilus exerts favorable preservation effects on noodles and breads.

Road Maintenance Planning with Traffic Demand Forecasting (장래교통수요예측을 고려한 도로 유지관리 방안)

  • Kim, Jeongmin;Choi, Seunghyun;Do, Myungsik;Han, Daeseok
    • International Journal of Highway Engineering
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    • v.18 no.3
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    • pp.47-57
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    • 2016
  • PURPOSES : This study aims to examine the differences between the existing traffic demand forecasting method and the traffic demand forecasting method considering future regional development plans and new road construction and expansion plans using a four-step traffic demand forecast for a more objective and sophisticated national highway maintenance. This study ultimately aims to present future pavement deterioration and budget forecasting planning based on the examination. METHODS : This study used the latest data offered by the Korea Transport Data Base (KTDB) as the basic data for demand forecast. The analysis scope was set using the Daejeon Metropolitan City's O/D and network data. This study used a traffic demand program called TransCad, and performed a traffic assignment by vehicle type through the application of a user equilibrium-based multi-class assignment technique. This study forecasted future traffic demand by verifying whether or not a realistic traffic pattern was expressed similarly by undertaking a calibration process. This study performed a life cycle cost analysis based on traffic using the forecasted future demand or existing past pattern, or by assuming the constant traffic demand. The maintenance criteria were decided according to equivalent single axle loads (ESAL). The maintenance period in the concerned section was calculated in this study. This study also computed the maintenance costs using a construction method by applying the maintenance criteria considering the ESAL. The road user costs were calculated by using the user cost calculation logic applied to the Korean Pavement Management System, which is the existing study outcome. RESULTS : This study ascertained that the increase and decrease of traffic occurred in the concerned section according to the future development plans. Furthermore, there were differences from demand forecasting that did not consider the development plans. Realistic and accurate demand forecasting supported an optimized decision making that efficiently assigns maintenance costs, and can be used as very important basic information for maintenance decision making. CONCLUSIONS : Therefore, decision making for a more efficient and sophisticated road management than the method assuming future traffic can be expected to be the same as the existing pattern or steady traffic demand. The reflection of a reliable forecasting of the future traffic demand to life cycle cost analysis (LCCA) can be a very vital factor because many studies are generally performed without considering the future traffic demand or with an analysis through setting a scenario upon LCCA within a pavement management system.

A Longitudinal Study of the Relationship Between Health Behavior Risk Factors and Dependence in Activities of Daily Living (건강위험행태인자와 일상생활 의존성과의 관련성에 대한 추적자료 분석)

  • Jung, Sang-Hyuk;Ostbye, Truls;Park, Kyoung-Ok
    • Journal of Preventive Medicine and Public Health
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    • v.39 no.3
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    • pp.221-228
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    • 2006
  • Objectives: The purpose of this study was to shed further light on the effect of modifiable health behavior risk factors on dependence in activities of daily living, defined in a multidimensional fashion. Methods: The study participants were 10,278 middle aged Americans in a longitudinal health study, the Health and Retirement Survey (HRS). A multi-stage probability sampling design incorporating the effect of population sizes (Metropolitan and non-metropolitan), ethnicity (the non- Hispanic White, the Hispanic, and the Black), and age (age 51-61) was utilized. Basic Activities of Daily Living (ADL) were measured using five activities necessary for survival (impairment in dressing, eating, bathing, sleeping, and moving across indoor spaces). Explanatory variables were four health behavior risk factors included smoking, exercise, Body Mass Index (BMI), and alcohol consumption. Results: Most participants at baseline were ADL independent (1992). 97.8% of participants were independent in all ADL's at baseline and 78.2% were married. Approximately 27.5% were current smokers at baseline, and the subjects reported moderate or heavy exercise were 74.8%. All demographic characteristics and behavioral risk factors were significantly associated with the ADL status at Wave 4 except alcohol consumption. Risk behaviors such as current smoking, sedentary life style and high BMI at Wave 1 were associated with ADL status deterioration; however, moderate alcohol consumption tended to be more related to better ADL status than abstaining at Wave 4. ADL status at Wave 1 was the strongest factor and the next was exercise and smoking affecting ADL status at Wave 4. People who were in ADL dependent at Wave 1 were 15.17 times more likely to be ADL dependent at Wave 4 than people who were in ADL independent at Wave 1. Concerning smoking cigarettes, people who kept only light exercise or sedentary life style at Wave 1 were 1.70 times more likely to be died at Wave 4 than the people who did not smoke at Wave 1. Conclusions: All demographics and health behaviors at wave 1 had consistently similar OR trends for ADL status to each other except alcohol consumption. Smoking and exercise in health behaviors, and age and gender in demographics at Wave 1 were significant factors associated with ADL group separation at Wave 4.

A Study on Factors Effecting the Hair Care of Female University Students (여대생의 모발건강관리행위에 영향을 미치는 요인에 관한 연구)

  • Cho, Sung-Sun;Moon, In-Ok
    • The Journal of Korean Society for School & Community Health Education
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    • v.3
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    • pp.1-13
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    • 2002
  • Female university students generally have a lower intake of nutrition compared to other age groups due to their adverse interests in their appearance. Drinking, smoking, too much weight control, accumulation of psychological and physical stress are causes of inadequate diet. The result is deterioration of hair health. Establishment of good diet and hair care is the foundation of a healthy hair in adulthood. For this reason, there is a great need for a healthy hair care. The data from a questionnaire survey was analyzed with 800 female undergraduate students responding. Seventeen universities were included in the study, 8 of which were from Seoul, 6 from other large cities and 3 from smaller towns. The objective of this study is to investigate the correlations of these factors and to provide preliminary data for developing an effective hair care education program. Results include the following: 1. Knowledge score of hair care based on general characteristics were higher for students in larger cites compare to small cites or regions. Also, students in higher academic year, more allowance, interest in their apparence and family income showed higher knowledge in this field. These factors had meaningful effect on the statistics of this study. 2. Attitude score towards hair care based on general characteristics were higher for students in larger cites compare to small cites or regions. Also, students in higher academic year, more allowance, interest in their apparence and family income showed higher knowledge in this field. These factors had meaningful effect on the statistics of this study. 3. Behavior score towards hair care was higher for students with greater family income, allowance, interest in appearance. These factors had meaningful effect on the statistics of this study. 4. The correlation study between knowledge, attitude and behavior showed that higher the knowledge and attitude, better the behavior. 5. The analysis of factors effecting hair care behavior showed that interest in health, acknowledgement of current hair condition, total family income were a viable factor in predicting hair care behavior. The predictability of regression model is 38.9 %($R^2$) Therefore, in order to maximize the hair care behavior, consistent and systematic study should be earned out to develope an effective education program to improve health interest.

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Some Chemical Properties in Sandy Soil Horizons of Degraded Apple Orchards (사질계(砂質系) 노후화(老朽化) 사과원(園) 토양(土壤)의 층위별(層位別) 수종(數種) 화학성분(化學成分) 분포(分布) 특성(特性))

  • Kang, Shin-Jyung;Choi, Jyung
    • Korean Journal of Soil Science and Fertilizer
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    • v.27 no.3
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    • pp.215-219
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    • 1994
  • This experiment was tried for finding out some soil chemical problems when new apple trees were replanted in old orchards. Soil samples were collected from the soil horizons in the old apple orchards cultivated over 40 years and reference soils. The non-cultivated reference soils were located near the old apple orchards and each of the soils was showed as the same pedon with each of the cultivated soils. The results were as follows : Soil pH showed a tendency to decrease in low horizons of the cultivated soils whereas increase in those of the uncultivated soils. As a comparision with each chemical component, the content of exchangeable Ca or total Mn was likely to be deficient in the cultivated soils. But all components except those were not like that. Total exchangeable cations in the cultivated soils were lower than in uncultivated soils. The pH in the cultivated soils showed very high positive correlation with total exchangeable cations. From those result, it was assumed that lower pH in lower horizon which would be originated from low content of total exchangeable cations, reacts as a factor for the deterioration of old apple orchard soil.

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A Plan for Establishing IOT-based Building Maintenance Platform (S-LCC): Focusing a Concept Model on the Function Configuration and Practical Use of Measurement Data (IOT 기반 건축물 유지관리 플랫폼 구축(S-LCC) 방안 : 기능구성과 계측 데이터 활용을 위한 개념 모델을 중심으로)

  • Park, Tae-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.611-618
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    • 2020
  • The reliability of the results of LCC analysis is determined by accurate analytical procedures and energy data from which the uncertainty is removed. Until now, systems that can automatically measure these energy data and produce databases have not been commercialized. Therefore this paper proposes a concept model of an S-LCC platform that can automatically collect and analyze electric energy consumption data of equipment systems using the IOT, which is the core tool in the Fourth Industrial Revolution and operates the equipment system efficiently using the analyzed results. The proposed concept model was developed by the convergence of existing BLCS and IOT and was comprised of five modules: Facility Control Module, LCC Analysis Module, Energy Consumption Control Module, Efficiency Analysis Module, and Maintenance Standard Reestablishment Module. Using the results of LCC analysis deduced from this system, the deterioration condition of an equipment system can be identified in real-time. The results can be used as the baseline data to re-establish standards for the maintenance factor, replacement frequency, and lifetime of existing equipment, and establish new maintenance standards for new equipment. If the S-LCC platform is established, it would increase the reliability of LCC analysis, reduce the labor force for entering data and improve accuracy, and would also change disregarded data into big data with high potential.

Removal of Algogenic Organic Matter in Drinking Water Treatment Process (정수처리공정에서 조류유래 유기물질의 제거)

  • Park, Se-Jin;Cha, Il-Kwon;Yoon, Tai-Il
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.4
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    • pp.377-384
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    • 2005
  • Algae causes not only the eutrophication of lake, but also the deterioration of drinking water process. Especially, algogenic organic matters(AOM) are assumed as disinfection by-products(DBPs) precursors like humic and fulvic acids. In this study, it was investigated the characteristics changes of algogenic organic matter(AOM) by prechlorination and coagulation treatment. Evaluation of enhanced coagulation and applicability of UV oxidation process were also evaluated as the drinking water treatment system for the eutrophicated water source. prechlorination was effective process for algae removal but caused releasing of dissolved organic matter(DOC) into water due to the destruction of algae's cell. In coagulation treatment with Fe(III) coagulant, reaction pH is an important factor for the removal of AOM and triholomathanes(THMs). At pH 5, removal efficiency of DOC and THMs were dramatically improved by 50% and 28%, respectively, in comparison with the conventional coagulation treatment at about pH 7. Photo-Fenton($UV/H_2O_2/Fe^{3+}$) process among the UV oxidations is the most effective system to remove AOM, but its removal efficiency was lower than that of enhanced coagulation treatment at pH 5.