• Journal of Korean Society on Water Environment
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• v.31 no.3
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• pp.235-240
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• 2015

To evaluate the unit load generation and discharge, pig cage test was conducted. Feed intake, drink amount, and urine generation increased growth stage (heavy weight) of the pig more great. However, the sum of the urine and manure did not show a significant difference in the growth stages of pigs. Because of the limit of the experiment, e.g., research period, high pigpen temperature, breed-related stress and etc., it could not be derived the results of the four seasons. Therefore, in order to generalize the results, the feed intakes were calibrated using a NRC (National Research and nutritional requirements of pigs from the Commission) standards. The finalized unit load generation and generation amounts of manure and urine were estimated at BOD 104.1 g/head/d, T-N 21.2 g/head/d, T-P 4.9 g/head/d, manure 0.96 L/d, urine 1.66 L/d with consideration of revised feed intake. Compare to the former research results of MOE (Ministry of Environment, 1999) and NIAS (National Institute of Animal Science, 2008), the generation amounts of manure and urine were similar to the NIAS's values. In case of unit load generation, BOD and T-N were almost similar in all of them. However, the T-P unit load generation of MOE was more difference, e.g., 2.5 times high, compare to this study.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.5
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• pp.17-27
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• 2018

The objective of this study is to identify the priority area where the nonpoint source pollution (NPS) management is required and to set up the load reduction goals for the identified priority area. In this study, the load duration curve (LDC) was first developed using the flow and water quality data observed at 286 monitoring stations. Based on the developed LDC, the priority area for the NPS pollution management was determined using a three-step method. The 24 watersheds were finally identified as the priority areas for the NPS pollution management. The water quality parameters of concern in the priority areas were the total phosphorus or chemical oxygen demand. The load reduction goals, which were calculated as the percent reduction from current loading levels needed to meet target water quality, ranged from 67.9% to 97.2% during high flows and from 40.3% to 69.5% during moist conditions, respectively. The results from this study will help to identify critical watersheds for NPS program planning purposes. In addition, the process used in this study can be effectively applied to identify the pollutant of concern as well as the load reduction target.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.307-310
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• 2005

Most of the electric power in the power system of South Korea is flowing from the south area to the north area, Seoul, in the capital of South Korea. Almost of the needs of the electric power in the capital area are about 43% of the total loads and generation plants are mainly located in the south area of South Korea. As mentioned the earlier characteristic, transmission congestion is one of the important research issues. Because of the limits of the power flows from the south to the north which are anticipated to be increased more and more in the future, these congestion situations may cause a serious voltage stability problem in emergency of the power system. Accordingly, we are interested in an interruptible load control program so as to solve this problem in emergency. This problem can be solved by an interruptible load management in emergency, however, the systematic and effective mechanism has not been presented yet. In this paper, the algorithm of interruptible load management plan using the line sensitivity to the loads for the transmission congestion management in emergency is presented. The proposed method is applied to 6-Bus sample system and their results are presented.

• Journal of Electrical Engineering and Technology
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• v.2 no.1
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• pp.42-49
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• 2007

For electricity markets to function in a truly competitive and efficient manner, it is not enough to focus solely on improving the efficiencies of power supply. To recognize price-responsive load as a reliability resource, the customer must be provided with price signals and an instrument to respond to these signals, preferably automatically. This paper attempts to develop the Windows-based load management system in competitive electricity markets, allowing the user to monitor the current energy consumption or billing information, to analyze the historical data, and to implement the consumption strategy for cost savings with nine possible scenarios adopted. Finally, this modeling framework will serve as a template containing the basic concepts that any load management system should address.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1455-1463
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• 2017

Global economy has recorded low growth, low consumption, high unemployment rate, high risk, short boom and long recession. As a result, maritime economy declines and the reduction of maintenance costs is inevitable. Thus, Studies such as green ship, eco ship, and smart ship are being actively conducted to save energy of ship. Power management system that use batteries in green ship is an important research area. In this paper, we analyze the heavy load control of a power management system of a general ship using only a generator, and study a heavy load control algorithm for a battery connected power management system. To study this, a structure of battery connected power management system is proposed and a battery connected power simulator was constructed based on the proposed system. Through the simulator, the operation of the battery according to the heavy load control is defined and confirmed in the battery connected power management system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.1
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• pp.16-22
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• 2016

This paper addresses the load usage scheduling in the HEMS for residential power consumers. The HEMS would lead the residential users to change their power usage, so as to minimize the cost in response to external information such as a time-varying electricity price, the outside temperature. However, there may be a consumer's inconvenience in the change of the power usage. In order to improve this, it is required to understand the pattern of load usage according to the external information. Therefore, this paper suggests a methodology to model the load usage pattern, which classifies home appliances according to external information affecting the load usage and models the usage pattern for each appliance based on a copula function representing the correlation between variables. The modeled pattern would be reflected as a constraint condition for an optimal load usage scheduling problem in HEMS. To explain an application of the methodology, a case study is performed on an electrical water heater (EWH) and an optimal load usage scheduling for EHW is performed based on the branch-and-bound method. From the case study, it is shown that the load usage pattern can contribute to an efficient power consumption.

• Journal of Korean Society on Water Environment
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• v.30 no.6
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• pp.622-631
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• 2014

The purpose of this research was to find a proper disposal rainfall extent to improve water quality. SWMM was applied to select catchment area and tested first flush load and rainfall extent. BOD 40mg/L was selected to dispose the first flush and sewer overflow with the same as the criteria of Sewerage Act. Design rainfall, BOD load ratio of first flush sewer overflow, and the ratio of disposal flow were analyzed under various rainfall distribution. BOD load and design rainfall to treat overflow in situation of first flush extent with 4.3~17.4% were 56~87% and 3.8~6.8 mm/day, respectively. In urban area, first flush loads were not correspond to land activities, but tend to increase with increasing rainfall amount and drainage area. The more the distribution of rainfall is similar to Huff-frontal or central distribution of rainfall, the more increase the first flush loads.

• Journal of the Korea Safety Management & Science
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• v.19 no.1
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• pp.203-210
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• 2017

Companies are pursuing the management of small quantity batch production or JIT(Just-in-time) system for improving the delivery response and LOB(Line Balancing) in order to satisfy consumers' increasing demands in the current global economic recession. And in order to improve the growth of production for reducing manufacturing cost, improvements of the Load Balancing have become an important reformation factor. Thus this paper is aimed at warehouse which procures materials on the assembly line in procurement logistics of automotive logistics and proceed with research on heuristic algorithm development which can increase the Load Balancing of workers. As a result of this study, when applied the primary target value, it was verified that the whole workers decreased from 28 to 24. Furthermore, when specified the secondary target value and applied algorithm once more, it was verified that the Load Balance Ratio was improved from 44.96% to 91.7%.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.17-18
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• 1991

In electric Industry, the improvement of load factor by flattening load has been considered to be more important than any other tasks and has received wide concern and interest. Especially while annual peak load had occurred early evening in winter during past decades, but we found the trend has changed so that annual peak load occurred during the daytime in summer since 1981. In this paper we introduce various method for the load management.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2007.11a
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• pp.477-481
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• 2007

The purpose of this study is to provide the ideal forecasting model of cadastral survey work load through the Economeatric Analysis of Time Series, Granger Causality and VAR Model Analysis, it suggested the forecasting reference materials for the total amount of cadastral survey general work load. The main result is that the derive of the environment variables which affect cadastral survey general work load and the outcome of VAR(vector auto regression) analysis materials(impulse response function and forecast error variance decomposition analysis materials), which explain the change of general work load depending on altering the environment variables. And also, For confirming the stability of time series data, we took a unit root test, ADF(Augmented Dickey-Fuller) analysis and the time series model analysis derives the best cadastral forecasting model regarding on general cadastral survey work load. And also, it showed up the various standards that are applied the statistical method of econometric analysis so it enhanced the prior aggregate system of cadastral survey work load forecasting.