• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.598-607
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• 2010

One of constraints in the application of unit-load method to estimate non-point pollution loads in the total water pollutant load management system (TWPLMS) is the limited numbers of applicable unit-loads. Since only 7 unit-loads are currently available for total 28 land-use categories in the national land register data, each unit-loads inevitably have to represent several land-use categories regardless of their actual land coverage characteristics. As a way to minimize the problem, this study suggested a nested application of the available unit-loads based on the analysis of high resolution aerial images taken in the Kyeongan watershed. Statistical analysis of three selected land-use categories such as school, apartment complex, and golf course showed that there exit significant (95% confidence level) relationships between the registered land-uses and actual land coverages. The school and apartment complex currently considered as 100% ground have only 65% and 80% of ground characteristics, respectively. Golf course, which is considered as 100% pasture, has about 5% of ground area. This indicates that the unit-load method using in TWPLMS can give over estimated non-point pollutant loads for the school and apartment complex (19.8~54.4%) but under estimation for the golf course (80.9%).

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.531-534
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• 1989

In this paper, the way that input voltage and input line current as a control variable is provided as one unit is projected. Till no, have denied with three phase balanced load. But, in that case, total power factor compensation is difficult, for to control each phase at unbalanced load. Therefor, in this paper suggest of the scheme that three phase unbalanced load is controlled by each phase and input total power factor is compensated unit input factor. therefore, in this paper suggest that three phase unbalanced load is controlled and the method in compensation of unit input factor to be attended by unbalanced load. Besides, the object of control is calculating quantity for input voltage and input line current for the point at issuse make to improve of control method at unbalanced load. As a result, control system of each phase could maintain as a unit input total power factor has been state diviation error of 2% with unbalanced load.

• Journal of Environmental Impact Assessment
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• v.24 no.5
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• pp.407-419
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• 2015

The unit load of paddy field was estimated by several methods and compared in this study. Four year field study was conducted at the paddy fields located in Yeongsan river and Sumjin river basins. The unit load was estimated by four methods; (1) averaging field monitored load; (2) NIER (National Institute of Environmental Research) method which use EMC(Event Mean Concentration) and runoff ratio of rainfall groups with rainfall weighting factors; (3)method using EMC determined by best fit probability distribution; (4)method using arithmetic mean EMC and runoff ratio. The result of this study showed that the unit loads of water quality constituents by field monitoring was similar to those of NIER method whereas those by probability distribution(log-normal, gamma) method were less than unit loads of NIER method. The unit loads by arithmetic mean EMC and runoff ratio were larger than those by NIER method. The unit load by NIER method showed higher BOD, COD, SS, lesser T-N, and similar T-P values when compared to unit loads determined by MOE in 1995.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.63-69
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• 2009

This paper provides the engineer with a simple design method dealing with situations arise where in-situ reinforced concrete joints are cast between hollow core units. Using finite element method, hollow core slabs with wide in-situ RC joints under point load and line loads are analysed. In addition, some important behavioural characteristics of the floor slab subjected to line and point loads are investigated. In-situ reinforced concrete joint causes reduction of load distribution for remote units because distance to the remote units from the point of load is increased, while the portion of load distribution carried by loaded unit increases. Also, it was turned out load distribution factors for point load and line loads are almost same. Finally, we suggest a simple analytical method, which can determine load distribution factors using normalized deflections by regression analysis for design purposes.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.1
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• pp.183-193
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• 2024

Recurrent Neural Network technology that learns past patterns and predicts future patterns using technology for recognizing and classifying objects is being applied to various industries, economies, and languages. And research for practical use is making a lot of progress. However, research on the application of Recurrent Neural Networks for evaluating and predicting the safety of mechanical structures is insufficient. Accurate detection of external load applied to the outside is required to evaluate the safety of mechanical structures. Learning of Recurrent Neural Networks for this requires a large amount of load data. This study applied the Gated Recurrent Unit technique to examine the possibility of load learning and investigated the possibility of applying a stacked Auto Encoder as a way to secure load data. In addition, the usefulness of learning mechanical loads was analyzed with the Gated Recurrent Unit technique, and the basic setting of related functions and parameters was proposed to secure accuracy in the recognition and prediction of loads.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.279-286
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• 2017

In this study, the characteristics of non-point source pollution runoff and the possibility of using new unit load were investigated by using pollutant load based on monitoring data considering baseflow. For this purpose, the components of hydrograph were separated by using digital filter method and the numerical integration method was applied to calculate the non-point source pollutant load for nine rainfall events in Juwon river in the Geum River basin. As a result of this study, the mean contribution rate of non-point pollutant was 31.34% for BOD, 58.94% for T-N, and 50.42% for T-P and BOD was more influenced by baseflow pollutant. Also, it was analyzed the pollutant load using the new unit load is closer to the observation load than the old unit load. This result implies that it is necessary to manage not only pollutant load due to direct runoff but also pollutant load due to baseflow runoff for efficient water quality management of the watershed.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.12
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• pp.591-596
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• 2002

This Paper Presents a new methodology for Direct Load Control(DLC) and Unit Commitment. To consider economical effect of DLC, we developed 3-Dimensional dynamic programming which can combine unit commitment and DLC. Traditional dynamic programming has 2-Dimensional which consist of state and stage, but newly developed dynamic programming has DLC state, U.C. state, and stage. As a result, economical DLC and unit commitment schedule of the power system is possible. This method is applied to the test system, and the usefulness of the method is verified.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.225-231
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• 2016

Peak load rate(i.e., maximum daily flow/average daily flow) has not been considered for industrial water demand planning in Korea to date, while area unit method based on average daily flow has been applied to decide capacity of industrial water treatment plants(WTPs). Designers of industrial WTPs has assumed that peak load would not exist if operation rate of factories in industrial sites were close to 100%. However, peak load rates were calculated as 1.10~2.53 based on daily water flow from 2009 to 2014 for 9 industrial WTPs which have been operated more than 9 years(9-38 years). Furthermore, average operation rates of 9 industrial WTPs was less than 70% which means current area unit method has tendency to overestimate water demand. Therefore, it is not reasonable to consider peak load for the calculation of water demand under current area unit method application to prevent overestimation. However, for the precise future industrial water demand calculation more precise data gathering for average daily flow and consideration of peak load rate are recommended.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.337-340
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• 2000

In this paper, the effects of the uncertain hourly load demand are stochastically analyzed especially by the consideration of the average over generation of the Unit Commitment(UC) results. In order to minimize the effects of the actual load profile change, a new UC algorithm is proposed. The proposed algorithm calculates the UC results with the lower load level than the one generated by the conventional load forecast. In case of the worse load forecast, the deviation of the conventional UC solution can be overcome with the lower load level and the more hourly reserve requirements. The proposed method is tested with sample systems, which shows that the proposed method can be used as the basic guideline for selecting the potimal load forecast applying to UC problem.

• 전기의세계
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• v.14 no.4
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• pp.8-17
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• 1965

Firstly, this study has analyzed the following factors affecting the optimum specifications and design of distributive transformers: 1. Facilities installation cost per unit power output. 2. Facilities operating & maintenance cost per unit power output. 3. Production cost per unit power output. 4. Load factor. 5. Loss factor. Secondly, it has clarified the relations between the following factors and the specifications and design of distributive transformers; 1. No-load loss., 2. Load loss., 3. Voltage regulation., 4. Exciting current. Finally, it has determined the method of the most economic design for the transformers using the above factors and relations, and, for optimum the illustrative purpose, suggested their optimum specifications, way of evaluation, and merits by means of typical example.