• Title/Summary/Keyword: power regulation

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A Study on the Strategies for the Reduction of Port Pollution (환경의 환경오염 저감방안에 관한 연구)

  • Song, Gye-Eui;Han, Chul-Hwan
    • Journal of Korea Port Economic Association
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    • v.23 no.1
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    • pp.95-113
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    • 2007
  • Recently, International institution such as IMO and major maritime countries have introduced various regulations and steps to reduce port pollution. However, recognition of environmental pollution from ports is not sufficient for Korean policy makers and port communities. The purpose of this paper is to examine solutions to port pollution problems and suggests some implications to Korean ports to become a green port. To this aim, necessity of regulation on environmental pollution from port operation; literature survey on port's environmental pollution; current conditions of international port pollution; various regulations and policies governing major ports are conducted in this paper. Our main findings are as follows; first, air pollution from ship can be reduced by providing electric power at docks while at berth, Second, in case of cargo-handling equipment, retire old equipment and switch to cleaner fuel such as low-sulfur fuel and diesel emulsions. Third, offering incentives for the installation of pollution controls and minimizing idling by enforcing idling limits or by installing idle shutoff controls can be recommended for reduction of air pollution of truck and rail at ports.

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A Study on Characters of Heart Rate Variability in Young Overweight and Obese Woman (젊은 비만 여성의 심박변이도 특성에 대한 연구)

  • Lee, Yoon-Jae;Hwang, Deok-Sang;Lee, Chang-Hoon;Lee, Kyung-Sub
    • Journal of Korean Medicine for Obesity Research
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    • v.8 no.1
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    • pp.63-70
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    • 2008
  • Objectives Obesity is the major risk factor of the heart disease and the metabolic disease. The autonomic nervous system is a key contributor in the regulation of energy balance, so the blunted activity may contribute to the maintenance of the obese state. So we evaluated the function of the autonomic nervous system in young overweight and obese women with heart rate variability. Methods The subjects were 26 overweight and obese young women(BMI〉$23kg/m^2$) and 25 lean women who visited Kangnam Kyunghee hospital for obesity management from March 2006 to April 2008. Bioimpedance Analysis (BIA), short-term spectral analysis of heart rate variability (HRV) were performed. Results HRV of obese young group was lower than the lean young group, but there is no statistical significance. BMI had significantly a negative correlation with Low Frequency(LF) of HRV. LF power is mediated by sympathetic nervous system activity. These results indicate a decrease of sympathetic modulation in overweight and obese young women. Conclusions Overweight and obese young women have decreased sympathetic nervous system activity. In clinical practice, an assessement of HRV would be noninvasive and sensitive methods for sympathetic nervous system of young overweight and obese women.

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A Study of Appropriate Devolution of Environmental Administrative Functions in Korea - Focused on the Transition of Environmental Official's Perception between 2001 and 2003 years - (한국 환경행정기능의 정부간 적정배분에 관한 연구 - $2001{\cdot}2003$년 환경행정공무원의 인식에 대한 비교를 중심으로 -)

  • Chung Yong-Taik;Lee Sung-Bock;Kim Jong-O;Son Bu-Soon
    • Journal of environmental and Sanitary engineering
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    • v.20 no.4 s.58
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    • pp.31-37
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    • 2005
  • The objective of this study is to analyze and suggest the policy on devolution of environmental administrative function between central and local government in Korea. This study also research to make the prospect of power from central government to local government's officers by analyzing the characteristics and contents, standards of local devolution and the attitudes of central and local governments on its process from September 2001 to April 2003. The date collected from the more than 675 questionnairs of government officers included as the Ministry of Environment and local government. The date also collected from interview and field survey. The questionnaire had collected in two times between 2001 and 2003. The environmental administrative function has reallocated from central government to local government since 2001. The devolution focused on simple implemental services and institutional delegated services might result in the lack of initiative and locality of local governments. Therefore, devolution should be proceed towards reinforcing the decision-making capacity and financial and manpower of local government. This paper also showed the weakness on speciality and experience on local bureaucratic in Korean society. This study announced that local government's officer has appeared the negative impact on environmental regulation and the conflict between central and local government.

Numerical study on fluid characteristics due to disc shape in a novel mechanical ballast water treatment system (신개념 기계식 선박평형수 처리장치의 디스크 형상에 따른 유동특성에 관한 수치해석 연구)

  • Sohn, Sang-Ho;Kim, Young-Chul;Choi, Kung-Kwan
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.1
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    • pp.19-27
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    • 2015
  • As the recent regulation of Internaional Maritime Organization (IMO) is enforced, the advanced technology of Ballast water treatment system (BWTS) is needed to meet its requirements. Until now, there are two kinds of the BWTS technologies such as physical methods (Membrane and UV) and chemical methods (Chlorin and Ozone). However, these conventional methods have some limitations of auxiliary power, low productivity, residual treatment and etc. In order to overcome these problems, this paper introduces the new kind of BWTS based on mechanical principle and investigates the effect of rotating disc shapes on flow characteristics between rotating and stationary discs by computational fluid dynamics (CFD). Planar and Step types can make the local cavitation generated along radius, and Circular type can increase the intensity of shear stress.

A study on the greenhouse gas emission from ships with training ship HANBADA (실습선 한바다호를 이용한 선박부문 온실가스 배출량 산정에 관한 연구)

  • Lee, Sang Deuk;Koh, Dae Kwon;Jung, Suk Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.3
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    • pp.240-245
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    • 2014
  • As the seriousness of the global environment pollution is gaining our attention recently, researches on application of greenhouse gas emission of ship are being carried globally. However domestic study on greenhouse gas emission from ship was not carried out in various fields. In this study, quantitative data which was presented by greenhouse gas emission of training ship HANBADA and greenhouse gas emission was calculated by Tier 1 method based on total fuel consumption and amount of shore power. Actual voyage data for 1year in 2012 was used to analysis the greenhouse gas emission. This study showed how many weight of gases were exhausted per 1 gross tonnage and per 1trainee in the training ship. There is a need of further research to reduce pollutant and to respond to international environment regulation consistently.

Mild stimulation of stomach 36 acupuncture point by organic nanoscale SP6 patch improves cellular physiologic functional status of different organs

  • Nazeran, Homer;Blake-Greenberg, Sherry;Haltiwanger, Emily
    • CELLMED
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    • v.2 no.1
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    • pp.10.1-10.6
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    • 2012
  • Acupuncture works by stimulating peripheral sensory nerves and their endings causing an increase in cutaneous blood flow and microcirculation, as well as release of neurotransmitters, neuropeptides, and hormones. SP6 Patch is a nanoscale nontransdermal device that mildly stimulates Stomach 36 (zusanli) and other acupuncture points. As stimulation of these points has been indicated to have an effect on hypothalamic function, it is of great research interest to investigate the effect of SP6 Patch on the physiology of organs that are affected by hypothalamic regulation. Bioelectrical tissue impedance data indicative of cellular physiologic organ function, using an Electro Interstitial Scan (EIS) system, were acquired from hypothalamus, pancreas, liver, intestines, kidneys, thyroid and adrenal glands in 10 (1 male, 9 females) volunteers while wearing the SP6 Patch daily for 1 week. EIS testing was performed at baseline with no patch, 30 min after wearing the patch, and after wearing the patch 12 h/day for 1 week. Subjects were instructed to keep well hydrated during the study period. All subjects served as their own control. The hypothesis was: The SP6 Patch worn 12 h/day on the Stomach 36 acupuncture point for 1 week, may significantly improve cellular physiologic functional status of different organs measured by EIS. All tested organs achieved significant improvement in their functional physiologic status after wearing the SP6 Pach 12 h/day for 1 week compared to baseline with an overall average statistical power > 89%. Based upon these results the hypothesis was accepted as true.

An Experimental Study on the Performance and Characteristics of Emission for an S.I. Engine with Methanol-Reformulated Fuel (메탄올 개질 연료를 이용한 S.I. 엔진의 성능 및 배기 배출물 특성에 관한 연구)

  • Jang, Yeong-Jun;Choe, Seung-Hwan;Ha, Cheol-Ho;Jeon, Chung-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.9
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    • pp.1193-1200
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    • 2001
  • There are many regulation test methods to be related with engine emissions such as CVS-75, D-13, ECE-15 modes and so on. Most of these modes are consisted of lots of transient conditions that have rapid acceleration, deceleration and cranking modes. In this experimental research, the engine characteristics of cranking, accelerating and power output in a S.I. engine were studied to compare with neat gasoline and alternative fuels of M30 (methanol 30%, aromatic series 32%, non-aromatic 38%) and M50 (methanol 50%, aromatic 30%, non-aromatic 20%) for performance and exhaust emissions. The results show that reformulated methanol fuels are better emissions reduction of 15.7% over than that of neat gasoline fuel especially in HC and CO emissions at cranking mode. And the accelerating performances coincide with the results of distillation curve. CO concentration for M50 fuel is varied in a just little for the condition of slow acceleration. At wide-open throttle condition, brake specific energy consumption of reformulated fuels is increased and thermal efficiency is some what lower than that of gasoline fuel.

Development of The New High Specific Speed Fixed Blade Turbine Runner

  • Skotak, Ales;Mikulasek, Josef;Obrovsky, Jiri
    • International Journal of Fluid Machinery and Systems
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    • v.2 no.4
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    • pp.392-399
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    • 2009
  • The paper concerns the description of the step by step development process of the new fixed blade runner called "Mixer" suitable for the uprating of the Francis turbines units installed at the older low head hydropower plants. In the paper the details of hydraulic and mechanical design are presented. Since the rotational speed of the new runner is significantly higher then the rotational speed of the original Francis one, the direct coupling of the turbine to the generator can be applied. The maximum efficiency at prescribed operational point was reached by the geometry optimization of two most important components. In the first step the optimization of the draft tube geometry was carried out. The condition for the draft tube geometry optimization was to design the new geometry of the draft tube within the original bad draft tube shape without any extensive civil works. The runner blade geometry optimization was carried out on the runner coupled with the draft tube domain. The blade geometry of the runner was optimized using automatic direct search optimization procedure. The method used for the objective function minimum search is a kind of the Nelder-Mead simplex method. The objective function concerns efficiency, required net head and cavitation features. After successful hydraulic design the modal and stress analysis was carried out on the prototype scale runner. The static pressure distribution from flow simulation was used as a load condition. The modal analysis in air and in water was carried out and the results were compared. The final runner was manufactured in model scale and it is going to be tested in hydraulic laboratory. Since the turbine with the fixed blade runner does not allow double regulation like in case of full Kaplan turbine, it can be profitably used mainly at power plants with smaller changes of operational conditions or in case with more units installed. The advantages are simple manufacturing, installation and therefore lower expenses and short delivery time for turbine uprating.

A Study of GDI+MPI Engine Operation Strategy Focusing on Fuel Economy and Full Load Performance using DOE (실험계획법에 의한 가솔린 GDI+MPI 엔진의 연비 및 성능향상 관점에서의 운전영역별 연료분사 전략에 관한 연구)

  • Kim, Dowan;Lee, Sunghwan;Lim, Jongsuk
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.3
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    • pp.42-49
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    • 2014
  • The gasoline direct injection (GDI) system is considerably spreading in automotive market due to its advantages. Nevertheless, since GDI system emit higher particle matter (PM) due to its combustion characteristics, it is difficult to meet strengthened emission regulation in near future. For this reason, a combined GDI with MPI system, so-called, dual injection (DUI) system is being investigated as a supplemental measure for the GDI system. This paper focused on power and fuel consumption effect by injection mode strategy of DUI system in part load and idle engine operating condition. In this study, port fuel injectors are installed on 2.4 liters GDI production engine in order to realize DUI system. And, at each injection mode, DOE (design of experiment) method is used to optimize engine control parameters such as dual injection ratio, start of injection timing, end of injection timing, CAM position and so on. As a consequence, DUI mode shows slightly better or equivalent fuel efficiency compared to conventional GDI engine on 9 points fuel economy mode as well as MPI mode shows less fuel consumption than GDI mode during idle operation. Furthermore, DUI system shows improvement potential of maximum 2.0% fuel consumption and 1.1% performance compared to GDI system in WOT operating condition.

Air Pollutants Control Technique Trends for Transportation Sources in Korea (우리나라 이동오염원의 제어기술의 동향과 발전방안)

  • Kim, Jeong-Soo;Eom, Myung-Do
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.4
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    • pp.477-485
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    • 2013
  • The major source of harmful air pollutants in Korea have been shifted as economy grows. Particulate matter(PM) and Sulfur dioxide ($SO_2$) emitted from industries and coal-fired domestic sectors were important pollutants in 1970's and later industrializing period of Korea. Then the characteristic of pollution was changed into so-called "developed country type pollution". Vehicles have been responsible for significant amount of Nitric oxide ($NO_x$) pollution and consequent Ozone formation in urban area since 1990's. Variety of control measures have been introduced to deal with the vehicle emissions in Seoul Metropolitan Area (SMA). Emission control technologies have successfully reduced pollutants from vehicles. Three-way catalyst for vehicles fueled by gasoline and liquefied petroleum gas (LPG), for example, has achieved large amount of pollutants. Compressed natural gas (CNG) urban bus have penetrated existing diesel bus market and reduces PM and $NO_x$ emissions in many Korean cities. However, diesel vehicles are still reaming as a critical emission source of urban area. Diesel vehicles gain more popularity than ever because of their better fuel efficiency and driving power. Unfortunately, it is widely known that the pollutant emissions of diesel vehicles are much larger than those of gasoline and LPG vehicles. In this note, we briefly introduce the trends of emission control strategies which are accomplished by automotive industries for about last ten years. Emission regulation, cleaner fuel, diesel particulate filter (DPF) and other measures are discussed from technical as well as legislative perspectives.