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Improvement and Implementation to Enhance the Effectiveness of the Total Pollution Load Control System (수질오염총량관리제 실효성 제고를 위한 제도개선 및 추진 방향)

  • Seok-Gyu Kim;Seung-Young Oh;Su-Young Park;Eun-Hye Na;Yong-Seok Kim
    • Journal of Korean Society on Water Environment
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    • v.39 no.4
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    • pp.343-355
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    • 2023
  • After the implementation of the total pollution load control system, the effect of improving river water quality by expanding investments in basic environmental facilities, inducing operational efficiency, and reducing the load of various pollutants was clear. However, since the implementation of the system, the management of non-point pollutants has been neglected; management focused on specific substances (biochemical oxygen demand (BOD) and total phosphorus (T-P)) and lacked specific cause analysis and action plans, failed to establish a relationship between water quality and pollution load, failed to reflect stakeholder demands for river water quality management, and failed to apply technical conditions. Therefore, to overcome the limitations raised and achieve a practical and efficient advanced total pollution system, the current system was partially improved and will continue to be improved. This study analyzed the performance and limitations of the total pollution system and introduced recent improvements and the contents that are being improved. The main contents included reducing emissions and reduction monitoring, using water quality tele-monitoring system (TMS) data and self-measurement data, adding population-inducing facilities, and adjusting regional development projects from 20 to 30 multi-family housing units, currentizing each pollutant source according to the roadmap. If the system is improved in a developmental direction and responds to various changes, it will be a more practical and effective policy.

A Study on System Engineering of Light Rail Transit Private Investment Projects (경량전철 민간투자사업의 시스템엔지니어링 연구)

  • Cha, Gi-Ho;Park, Jin-Jae;Lee, Jae-Hyeong;Chu, Dong-Su
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.517-544
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    • 2011
  • Promote competition in local government and the construction of a subway construction in the vicious cycle of debt due to the operating deficit as a greater burden on local finances was leave. This government policy of public transport in the center of the metro construction costs affordable and to respond appropriately to public transport demand new transit LRT(Light rail Transit) by introducing the current Busan was the opening of Line 4, yongin line, Busan - Gimhae line, parliamentary and barge construction or ready for the opening. What is light rail, compared to the existing subway and cheaper construction cost, the existing road or bridge that runs along the track is installed, etc. Manless system construction cost and operating expenses as a possible new railway transportation has been a leading state-of-the-art mad. However, the domestic business system engineering of light rail-related companies in the developed countries are doing to advance to the national to the local engineering skills of the self-free, hurry will have to be secured. Therefore, this paper applies local light rail project on the status of the systems engineering analysis and based on this source of the latest engineering technology-intensive systems engineering to provide direction to the development of technology.

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Challenges in neuro-machine interaction based active robotic rehabilitation of stroke patients

  • Song, Aiguo;Yang, Renhuan;Xu, Baoguo;Pan, Lizheng;Li, Huijun
    • Advances in robotics research
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    • v.1 no.2
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    • pp.155-169
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    • 2014
  • Study results in the last decades show that amount and quality of physical exercises, then the active participation, and now the cognitive involvement of patient in rehabilitation training are known of crux to enhance recovery outcome of motor dysfunction patients after stroke. Rehabilitation robots mainly have been developing along this direction to satisfy requirements of recovery therapy, or focusing on one or more of the above three points. Therefore, neuro-machine interaction based active rehabilitation robot has been proposed for assisting paralyzed limb performing designed tasks, which utilizes motor related EEG, UCSDI (Ultrasound Current Source Density Imaging), EMG for rehabilitation robot control and feeds back the multi-sensory interaction information such as visual, auditory, force, haptic sensation to the patient simultaneously. This neuro-controlled and perceptual rehabilitation robot will bring great benefits to post-stroke patients. In order to develop such kind of robot, some key technologies such as noninvasive precise detection of neural signal and realistic sensation feedback need to be solved. There are still some grand challenges in solving the fundamental questions to develop and optimize such kind of neuro-machine interaction based active rehabilitation robot.

Direction for Development of Energy Regeneration Device for DC Electric Railway System (DC전철구간의 에너지회생장치 개발 방향)

  • Kim, Yong-Ki;Bae, Chang-Han;Han, Moon-Seob;Yang, Young-Chul;Jang, Su-Jin
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.804-808
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    • 2007
  • when electric traction system used DC 1500V runs on decline of rail road track and slows down, Dc voltage goes beyond regular voltage. In this case extra power is forcibly wasted by resister because rectifier of substation and electric train including power converter and so on are out of order. This paper described a DC electric railway system, which can generate the excessive DC power form DC bus line to AC source in substation for traction system. The proposed regeneration inverter system for DC traction can be used as both an inverter and an active power filter(APF). As a regeneration inverter mode, it can recycle regenerative energy caused by decelerating tractions and as an active power filter mode, it can compensate for harmonic distortion produced by the rectifier substation. In addition, electric traction system products harmonic current and voltage distortion and reactive power because power converter is used so regeneration inverter normally runs such as active power filter(APF) for improving power quality. From the viewpoint of both power capacity and switching losses, the system is designed on the basis of three phase PWM inverters and composed of parallel inverters, output transformers, and an LCL filter.

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Current Status of Intensive Observing Period and Development Direction (집중관측사업의 현황과 발전 방향)

  • Kim, Hyun Hee;Park, Seon Ki
    • Atmosphere
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    • v.18 no.2
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    • pp.147-158
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    • 2008
  • Domestic IOP (intensive observing period) has mostly been represented by the KEOP (Korea Enhanced Observing Period), which started the 5-yr second phase in 2006 after the first phase (2001-2005). During the first phase, the KEOP had focused on special observations (e.g., frontal systems, typhoons, etc.) around the Haenam supersite, while extended observations have been attempted from the second phase, e.g., mountain and downstream meteorology in 2006 and heavy rainfall in the mid-central region and marine meteorology in 2007. So far the KEOP has collected some useful data for severe weather systems in Korea, which are very important in understanding the development mechanisms of disastrous weather systems moving into or developing in Korea. In the future, intensive observations should be made for all characteristic weather systems in Korea including the easterly in the central-eastern coastal areas, the orographically-developed systems around mountains, the heavy snowfall in the western coastal areas, the upstream/downstream effect around major mountain ranges, and the heavy rainfall in the mid-central region. Enhancing observations over the seas around the Korean Peninsula is utmost important to improve forecast accuracy on the weather systems moving into Korea through the seas. Observations of sand dust storm in the domestic and the source regions are also essential. Such various IOPs should serve as important components of international field campaign such as THORPEX (THe Observing system Research and Predictability EXperiment) through active international collaborations.

A Study on Characteristics of Hydrogen Leakage in Hydrogen Town Governor Room (수소타운 정압기실 내 수소 누출 특성 연구)

  • NAM, TAE-HO;KIM, DONG-HWAN;LEE, JUNG-WOON;LEE, SEUNG-KUK;LEE, YEON-JAE
    • Journal of Hydrogen and New Energy
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    • v.27 no.6
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    • pp.685-692
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    • 2016
  • Hydrogen will be a future eco-friendly energy source that can replace current fossil fuels However when hydrogen gas leaks and people inhale a lot of hydrogen gases, they can have fatal effects fell into comas. Therefore, we need to develop a safety technology and related guidelines for reducing risks of hydrogen leakage. In this regard, we carried out demonstration tests assuming a situation of hydrogen leakage. Before the experiments, we analyze the standards for governor facilities to check vent positions and sensor positions. Then, we select four types of ventilation structures and proceeds with the experiments of hydrogen leakage at 1 LPM and 1.5 LPM. Based on the experimental results, we propose the direction on optimization of vent positions and sensor positions in the hydrogen leakage situation.

DC-DC Converter for Integrated Voltage Control Method (전압 적분 제어법에 의한 DC-DC 컨버터)

  • 이현우;서기영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.10
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    • pp.1590-1597
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    • 1993
  • Power conversion system generally requires bidirectional converter. A storage energy of reactor is suppressed by regeneration of surplus electic energy in converter to power source. When an electric isolation in the power conversion system is required. the most suitable position for the isolation is the DC-Link part. A transformer in the DC part is minimized because of high repetition frequency. This paper proposes that power conversion system becomes bidirectional DC-DC converter with electric isolation by intergrated voltage control method. It is intergrated voltage control that makes system construciton simple, has control errow little quantity ans gets output response Quick. And the power-switches which should be operated is selected automatically without a detection of the current-direction.

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Removal of Flooding in a PEM Fuel Cell at Cathode by Flexural Wave

  • Byun, Sun-Joon;Kwak, Dong-Kurl
    • Journal of Electrochemical Science and Technology
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    • v.10 no.2
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    • pp.104-114
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    • 2019
  • Energy is an essential driving force for modern society. In particular, electricity has become the standard source of power for almost every aspect of life. Electric power runs lights, televisions, cell phones, laptops, etc. However, it has become apparent that the current methods of producing this most valuable commodity combustion of fossil fuels are of limited supply and has become detrimental for the Earth's environment. It is also self-evident, given the fact that these resources are non-renewable, that these sources of energy will eventually run out. One of the most promising alternatives to the burning of fossil fuel in the production of electric power is the proton exchange membrane (PEM) fuel cell. The PEM fuel cell is environmentally friendly and achieves much higher efficiencies than a combustion engine. Water management is an important issue of PEM fuel cell operation. Water is the product of the electrochemical reactions inside fuel cell. If liquid water accumulation becomes excessive in a fuel cell, water columns will clog the gas flow channel. This condition is referred to as flooding. A number of researchers have examined the water removal methods in order to improve the performance. In this paper, a new water removal method that investigates the use of vibro-acoustic methods is presented. Piezo-actuators are devices to generate the flexural wave and are attached at end of a cathode bipolar plate. The "flexural wave" is used to impart energy to resting droplets and thus cause movement of the droplets in the direction of the traveling wave.

The Impact of Recreational Sports Enthusiasts' Willingness to Engage in the Leisure Consumption

  • Dong-Ho SEONG
    • The Journal of Industrial Distribution & Business
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    • v.15 no.2
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    • pp.31-39
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    • 2024
  • Purpose: The present research guides to a middle ground where recreational sports and enjoyment justify the basic concept of leisure consumption, exploring an exciting field of study, where participation is the motivational source of recreational sports fans for transferring into the motivation of leisure activities and leisure consumption. Research design, data and methodology: This research took a close look at the current literature to investigate impacts of recreational sports enthusiasts' willingness to engage in the leisure consumption. The screening and excluding procedure took a place to select a qualified prior resources and the present author finally obtained a total of 19 highly relevant papers. Results: The evaluation of the presented research shows that the enthusiasts' participation in avocational sports has four significant implications on their lifestyle and leisure consumption. These impacts are categorized as follows: Economic influence, Psychological influence, Social influence, and Environmental influence. Conclusions: In sum, this study has shown the various ways and magnitude in which willingness to participate in leisure affects its consumption by the recreational sports enthusiast. These impacts have brought critical implications for the viability of the sport leisure business in the industry, particularly in urging it to be the right strategic direction to cater to this market segment.

Current Status of Domestic and Overseas Research of the Characteristics and Use of Deep Sea Water (해양심층수의 특성과 이용 및 국내외 연구현황)

  • Chung, Kap-Taeck;Lee, Sang-Hyun
    • The Korean Journal of Food And Nutrition
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    • v.21 no.4
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    • pp.592-598
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    • 2008
  • Deep sea water is found more than 200 m under the surface. As no sunlight reaches, no photosynthesis takes place, and it has very little organic matter or bacteria. In addition, deep sea water maintains a consistently low temperature throughout the year, and it does not mix with the water found closer to the surface, which means that its cleanliness is preserved. It is a long-term mature sea water resource that is rich in minerals. This paper examined the physical characteristics and the uses of deep sea water, a subject that has been attracting a great deal of public attention recently, together with the current status of domestic research into it and the direction of research in the USA and Japan, focusing on the existing literature. The aim of this paper was to provide are source to researchers in the field. Since the 1970s, scientists around the world have recognized the importance of deep sea water, and have been conducting research into it. In the USA, deep sea water has been researched with the view of its application to cooling, alternative energy, farming, and the development of new materials. In Japan, about 10 local self-governing bodies are currently promoting research and business relating to deep sea water, which has resulted in a number of products that have been released to the market. In Korea, the ministry of land transport and marine affairs has been studying deep sea water since 2000, and full-scale national R&D projects have been performed by 24 organizations, including KORDI, through industrial/academic cooperation. Large companies are participating in deep sea water research projects in several ways. A study of data foundusing NDSL relating to domestic studies of deep sea water found 50 theses, 177 domestic patents, 6 analyses, 2 reports, and 2 etc. in other areas.