• Journal of Korean Society of Rural Planning
• /
• v.26 no.3
• /
• pp.39-47
• /
• 2020

While agricultural water has been declared free in Korea to ensure access to these limited resource since the year 2000, farmers have however developed lackadaisical behavior towards water saving leading to its scarcity. To overcome this problem, a variety of experience-oriented education model was developed for farmers to promote the adoption of water conservation, and preventive measure against the drought impacts. In this study, farmers' awareness and their attitudinal behavior of agricultural water savings were investigated. The monitoring of water supply structure and the repair facilities in Pohang and Yeongdeok areas were conducted. The field visits and behavioral surveys showed a high degree of over-use and illegal water withdrawals by the farmers due to poor water-saving and management practices. We found that most of the KRC employees strongly admitted the necessity of water-saving education. On the other hand, the farmers showed good interest in the implementation of water-saving awareness through education. Besides this, most farmers agreed to adopt water-saving practices in the fields. Farmers also acknowledged the recklessness of water use was due to the aging of waterways, poor water management, and illegal water consumption. The majority of the farmers responded against imposing the water-use tariffs. However, there was a low response to paying the water-use charge. Aging agricultural facilities and the lack of institutional penalties or incentives were the major obstacles in achieving efficient water-saving. Considering the current drought frequency, urgent water-saving education of farmers was deemed necessary to prepare the farming community against the water shortages. Based on the results of this study, we have to identify the irrigation practices of farmers and provide water-saving education to enforce more efficient use and management of agricultural water.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.465-470
• /
• 2009

This study investigated the water saving technology for the toilet stool system in a water closet. Since in 21st century water would be the prospected factor to measure the wealth of a country instead of the oil, water saving technologies in the toilet stool in a closet system is getting more important than the cleaning stool and the reducing noise performances. According to the statistics in Korea the percentage of using water in toilet is about 27% to the total amount of water used. Therefore, this study theoretically approached the possible amount of water saving and suggested the new variable position straight trap device in the toilet stool system.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.10 no.1
• /
• pp.33-39
• /
• 2011

This paper considers a performance analysis of set-top box (STB) power saving schemes. STB converts the signal into content which is then displayed on the television (TV) screen, and there are typically two operation modes: on mode and stand-by mode. The total energy consumption (TEC), a typical measure of power consumption of STB, is defined by the sum of power consumption in each mode. Recently there are some works of STB power saving schemes that transit STB operation modes efficiently, and the mode transition time point of those schemes can be different. Thus it is required to develop a performance evaluation method that reflects mode transition time points of each scheme to get TEC correctly. This paper proposes a performance evaluation method for STB power consumption using Poisson process to consider the mode transition time point. By modeling STB mode transitions as events of Poisson process, the average time duration of STB mode is computed and accordingly the effect of power saving is evaluated. The performance evaluation result shows that the proposed method achieves 1 to 19% improvement in power consumption compared with a conventional performance evaluation method.

• Journal of Advanced Marine Engineering and Technology
• /
• v.38 no.9
• /
• pp.1057-1063
• /
• 2014

Concerning $CO_2$ reduction from International Societies, lots of laboratories and relevant societies suggest many reports on how to reduce fuel consumption from their specific ways. Undoubtedly, cutting costs is the final desired destination for owner outcome, but many questions there are on the way yet: how is this measure working? how efficient is it? On what size of ship would it work best and be the most effective? etc. Fuel cost is one of the major cost elements for ship owners and/or operators. And by reducing fuel consumption owners and/or operators will reduce both their costs and the environmental impact from their ship. This paper is aim to address how the measures work for saving fuel consumption through improve propulsion efficiency, installation cost and benefit can be calculated easily in the return on investment for estimated one year operation, and finally their compatibility with other fuel saving measure devices.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.10
• /
• pp.161-167
• /
• 2015

This paper presented an occupancy-based energy saving system for appliance energy saving in smart house. The developed system is composed of a sensing system and a home gateway system. The sensing system is set of wireless sensor nodes which have pyroelectric infrared (PIR) sensor to detect a motion of human and set of smart plugs which measure the current using CT (current transformer) sensor and send the current to home gateway wirelessly. We measured current consumption of appliances in real time using smart plugs, and checked the occupation of residents using occupancy sensors installed on the door and room. The proposed system saves electric energy to switch off the supply power of unnecessary usages in the unoccupied spaces. Experiments conducted have shown that electric energy usage of appliances can be saved about 34% checked by using occupation.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.50 no.1
• /
• pp.67-74
• /
• 2014

Most of steam power plants in Korea are using the method of heating the feed water whenever the ambient temperature around the power plant area below $5^{\circ}C$ to prevent freezing water flowing in the pipe in winter time. But this kind of heat supplying system is not useful to save energy. If we take the method that the temperature of the each pipe is controled by direct measure of temperature by attaching sensor on the outside surface of the feed water tubes, then we can expect that a plenty of energy can be saved. In this study, the computer simulation is used to compare the energy consumption loads of both systems. Energy saving rate is calculated for the location of Incheon area in winter season. Four convection heat transfer coefficients for the ambient air and three initial flowing water temperature inside the tube were used. The result shows that the temperature control system using sensor represents more than 95% of energy saving rate in Incheon area. Even in the severe January weather condition, the energy saving rate is almost 75% in two days basis and even 83% in one day basis.

• Journal of Energy Engineering
• /
• v.23 no.2
• /
• pp.199-206
• /
• 2014

ESCO industry should guarantee the energy saving performance in response to changes of regulations ESCO. In this point, the application of the M&V is important task on energy saving performance. Therefore, we need to examine the contents of practice for the M&V in developed countries. Between energy user and ESCO, it is important to provide and measure the energy saving performance by guarantee of energy savings performance contracts. After 2013 ESCO business began focusing on guaranteed savings contracts. For this reason, we need to take M&V cases recommended from IPMVP and applied in United States and Japan. Therefore, we should be ready about M&V application for the real conditions of ESCO.

• Journal of the Korean Society for Precision Engineering
• /
• v.32 no.4
• /
• pp.345-351
• /
• 2015

Machine tools usually consume more energy in cooling systems than in spindle motors. This is largely because circulation pumps in the cooling systems are continuously powered to measure the temperature of spindle motors. In this paper, energy saving algorithms are proposed, which modify this behavior of the circulation pumps in such a way that the circulation pumps run only when it is likely that the information on the temperature is critical to bang-bang control of compressors in cooling systems. A mathematical model is established that explains heat transfer phenomena near the spindle motors. The power consumptions are measured for individual components in a machine tool, and the parameters that appear in the mathematical model are estimated. Computer simulations are performed with the estimated parameters, and the results are compared with the experimental ones. It turns out that a large amount of energy can be saved by using the proposed method.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06d
• /
• pp.360-365
• /
• 2010

In this paper, we present a distributed algorithm for detecting dynamic event regions in wireless sensor network with the consideration on energy saving. Our model is that the sensing field is monitored by a large number of randomly distributed sensors with low-power battery and limited functionality, and that the event region is dynamic with motion or changing the shape. At any time that the event happens, we need some sensors awake to detect it and to wake up its k-hop neighbors to detect further events. Scheduling for the network to save the total power-cost or to maximize the monitoring time has been studied extensively. Our scheme is that some predetermined sensors, called critical sensors are awake all the time and when the event is detected by a critical sensor the sensor broadcasts to the neighbors to check their sensing area. Then the neighbors check their area and decide whether they wake up or remain in sleeping mode with certain criteria. Our algorithm uses only 2 bit of information in communication between sensors, thus the total communication cost is low, and the speed of detecting all event region is high. We adapt two kinds of measure for the wake-up decision. With suitable threshold values, our algorithm can be applied for many applications and for the trade-off between energy saving and the efficiency of event detection.

• Journal of Distribution Science
• /
• v.20 no.7
• /
• pp.73-86
• /
• 2022

Purpose: Considering the COVID-19 pandemic and the increasing number of online food delivery applications (OFDA), this study aims to assess the distribution of the presence of Indonesian OFDA and to measure the factors that influence the spending habits of OFDA users. Research design, data and methodology: Two hundred and nine OFDA users from Jakarta's Generation Z were surveyed via a questionnaire. The data were analyzed using Structural Equation Modeling and SMART PLS 3.0. Results: OFDAs were introduced into Indonesia in the recent past with varying degrees of popularity determined by the number of downloads. Users' intention to use was not determined by the speed of the introduction of an OFDA. This study also reveals that previous experience of the service, the orientation of time and price savings had a significant effect on spending habits. A moderating role of the saving variable on time and price was not demonstrated. Conclusions: The results of the study suggest that, in COVID-19 pandemic conditions, the spending habits of Generation Z are not based on impulse, thrift, or extravagance. The pandemic shaped specific motivations in spending habits, namely prioritizing need. This study has limitations, including the small sample size and the use of internal variables.