• Journal of Biosystems Engineering
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• 제33권5호
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• pp.309-316
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• 2008

The goal of this study was to develop prediction models to estimate the storage days of tomato. The transmittance spectral data measured on tomato were preprocessed through normalization, SNV, Savitzky-Golay, and Norris Gap and then were used to build the prediction models using partial least square (PLS) method. For the experiments, the tomato samples of different varieties were collected at different harvest time. The samples were taken right after harvest from the field and then were stored in a low-temperature storage room in which room temperature was maintained at $10^{\circ}C$. The transmittance spectral data of the tomato samples were measured at three-day intervals for 16 days. The performance of the prediction models was affected by the preprocessing techniques as well as the varieties and harvest time of the tomato. The best model was found when SNV was applied. The accuracy of the best model was 90.2%. It can be concluded that the transmittance spectra are useful information for predicting the period of storage of tomato.

• Journal of Biosystems Engineering
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• 제42권1호
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• pp.62-68
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• 2017

Purpose: The storage life of pearl millet-based, deep fried, ready-to-eat snacks, packaged in aluminum-laminated polyethylene having a thickness of $50{\mu}m$ (with and without nitrogen) was evaluated under storage conditions of $38{\pm}2^{\circ}C$ and 90% RH. Methods: The moisture content, free fatty acids (FFA), peroxide value, and crispness of the snack were evaluated throughout the storage period. The moisture content, FFA, and peroxide value increased with an increase in storage period, but the increase was less in packages flushed with nitrogen gas. The crispness decreased with an increase in the storage period, for snacks both with and without nitrogen packages. However, the decrease was less in nitrogen-flushed packages. FFA and peroxide values were strongly correlated with the moisture content of the snack. The storage life of the snack was found to be 60 and 45 days in packages with and without nitrogen respectively. Conclusions: The snack's predicted storage life, for snacks with and without nitrogen packages, was determined as 294 and 254 days respectively.

• 상하수도학회지
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• 제19권2호
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• pp.173-180
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• 2005

In this study, quantity and quality of collected rainwater by the ground collection system were investigated and the Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in the collection system was 9516 L(38.2%) and the quantity of infiltrated rainwater in the collection system was 9946 L(40.2%) through $25m^2$ area for the study period, respectively. Average turbidity of collected rainwater in collection system was 2.2 NTU, and average turbidity of infiltrated rainwater in collection system was 2.3 NTU for study period, respectively. The predicted amount by the model and the actual collected amount were 9842.4 L and 9516 L, which were very close showing that prediction was excellent. The optimal rainwater storage tank volume was simulated with a certain consumption condition for various cities with different rainfall patterns.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.307-307
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• 2022

• 상하수도학회지
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• 제18권1호
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• 설비공학논문집
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• 제12권11호
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• pp.982-993
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• 2000

This paper describes an optimal control scheduling of an encapsulated ice storage system with a chiller of nominal chiller 34RT(103,200kcal/hr) and an ice storage tank of 170RT-hrs(514,080 kcal). The optimization technique used in the study is dynamic programing. The objective function is summed cost during a day including charge and discharge periods. Control strategies being used commercially are chiller priority and storage priority control. In chiller priority control, the chiller is allowed to run at full capacity during the day, subject to limitations of the building load, and the ice is only melted when and if the load exceeds the chillers full capacity. In contrast to chiller priority control, the aim in storage priority control is to melt as much as ice as possible during the day time period. The system simulation calculates the operation costs for the three control strategies in the condition of the same cooling load and the same ice storage system. The simulation period is a day, assuming that initially the tank is stored fully and the cooling load is perfectly predicted for the scheduling. Also Final state of the tank is to be charged fully.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.611-612
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• 2015

Prediction algorithm of the energy storage system in accordance with the load pattern can cause economic loss in case of a failure prediction. In this paper, we compare the electricity charge between industrial power system with ESS - this case's operation is based on Non-prediction operation method. - and without ESS. In addition, we derive the payback period.

• 한국농공학회논문집
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• 제49권4호
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• pp.3-12
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• 2007

The purpose of this paper is to analyze the relationship between meteorological factors and agricultural reservoir storage, and predict the reservoir storage by multiple regression equation selected by high correlated meteorological factors. Two agricultural reservoirs (Geumgwang and Gosam) located in the upsteam of Gongdo water level gauging station of Anseong-cheon watershed were selected. Monthly reservoir storage data and meteorological data in Suwon weather station of 21 years (1985-2005) were collected. Three cases of correlation (case 1: yearly mean, case 2: seasonal mean dividing a year into 3 periods, and case 3: lagging the reservoir storage from 1 month to 3 months under the condition of case 2) were examined using 8 meteorological factors (precipitation, mean/maximum/minimum temperature, relative humidity, sunshine hour, wind velocity and evaporation). From the correlation analysis, 4 high correlated meteorological factors were selected, and multiple regression was executed for each case. The determination coefficient ($R^{2}$) of predicted reservoir storage for case 1 showed 0.45 and 0.49 for Geumgwang and Gosam reservoir respectively. The predicted reservoir storage for case 2 showed the highest $R^{2}$ of 0.46 and 0.56 respectively in the period of April to June. The predicted reservoir storage for 1 month lag of case 3 showed the $R^{2}$ of 0.68 and 0.85 respectively for the period of April to June. The results showed that the status of agricultural reservoir storage could be expressed with couple of meteorological factors. The prediction enhanced when the storage data are divided into periods rather than yearly mean and especially from the beginning time of paddy irrigation (April) to high decrease of reservoir storage (June) before Jangma.

• 한국식품조리과학회지
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• 제15권2호
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• pp.127-132
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• 1999

건면을 7개월 동안 저장하면서 수분활성도, 호화양상, 색깔의 변화 및 조리면의 특성변화를 측정하여 이들 지표항목으로부터 적절한 shelf-life를 예측하였다. 저장기간중의 수분활성도는 0.43~0.56 정도로 저장온도 및 기간에 따라 일률적인 변화를 보이지 않았다. 아밀로그람에 의한 최고점도, breakdown 값은 저장기간이 증가함에 따라 증가하였다. 한편 저장기간에 따른 건면류의 색차(color difference)는 저장기간 및 저장온도에 따라 비례적으로 증가되는 경향을 보였으며, 이는 관능검사와 좋은 상관관계를 보여 건면의 품질지표로 이용할 수 있었다. 건면의 색택의 변화에 대한 활성화에너지는 75.21 kJ/mo1 이었으며, 온도계수(Q$_{10}$ value)는 $25^{\circ}C$~35$^{\circ}C$에서 2.76, 35$^{\circ}C$~45$^{\circ}C$에서 2.51이었다. 건면의 저장한계 기간은 $25^{\circ}C$에서 27.9개월 정도인 것으로 나타났다.

• 산업식품공학
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• 제21권4호
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• pp.312-317
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• 2017

감모율에 영향을 주는 인자를 파악하고 온습도 변화, 제상수, VPD방법을 이용해 감모율을 예측하였으며 실제 감모율과 비교분석을 진행하였다. 저장고 내부의 습도변화를 이용하여 예측한 결과 질소주입과정보다 유닛쿨러의 운전과정에서 발생하는 응축 결상 수분배출 과정이 지배적인 영향을준다. 또한 온습도를 이용한 감모율 예측방법이 실제 감모율과 가장 근사값을 나타냈다. 제상수를 이용해 예측한 결과 감모량은 유닛쿨러의 운전율이 높아질수록 많아졌으며 온습도를 이용한 예측방법보다 운전특성에 따른 감모율 변화가 더 뚜렷하게 나타났다. 이때 유닛쿨러의 운전율은 외기온도와 비례하였으며, 저장고 내부에서 응축된 수분량의 계측이 어렵기 때문에 실제 감모율과 오차가 발생한 것으로 보인다. VPD를 이용한 감모율 예측은 증산계수(K-value)의 영향이 지배적이며, 보고되어진 본 연구에서 이용한 후지사과의 증산계수값(42)에 대한 검증이 필요하다. 본 연구에서 후지사과의 K-value를 30으로 수정하였을 때 가장 근사한 예측값을 계산할 수 있었다.