• Title/Summary/Keyword: clean power

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The Characteristics Study of Vehicle Evaporative Emission and Performance according to the Bio-Fuel Application (바이오 연료 적용에 따른 차량 증발가스 및 성능특성 연구)

  • Noh, Kyeong-Ha;Lee, Min-Ho;Kim, Ki-Ho;Kim, Sin;Park, Cheon-Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.874-882
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    • 2017
  • As the interest on the air-pollution is gradually rising up at home and abroad, automotiv e and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward three main issues : evaporative, performance, air pollution. In addition, researcher studied the environment problems of the bio-ethanol, bio-butanol, bio-ETBE (Ethyl Tertiary Butyl Ether), MTBE (Methyl Tert iary Butyl Ether) fuel contained in the fuel as octane number improver. The researchers have many dat a about the health effects of ingestion of octane number improver. However, the data support the con clusion that octane number improver is a potential human carcinogen at high doses. Based on the bio-fuel and octane number improver types (bio-ethanol, bio-butanol, bio-ETBE, MTBE), this paper dis cussed the influence of gasoline fuel properties on the evaporative emission characteristics. Also, this p aper assessed the acceleration and power performance of gasoline vehicle for the bio-fuel property. As a result of the experiment, it was found that all the test fuels meet the domestic exhaust gas standards, and as a result of measurement of the vapor pressure of the test fuels, the bio - ethanol : 15 kPa and the biobutanol : 1.6 kPa. thus when manufacturing E3 fuel, Increasing the biobutanol content reduces evaporation gas and vapor pressure. In addition, Similar accelerating and powering performance was shown for the type of biofuel and when bio-butanol and bio-ethanol were compared accelerated perf ormance was improved by about 3.9% and vehicle power by 0.8%.

Environmental Dispute Adjustment System : Current Status and Issues (환경분쟁조정제도의 현황과 과제)

  • Yoon, Esook;Lee, Choon-Won
    • Journal of Arbitration Studies
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    • v.28 no.1
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    • pp.125-151
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    • 2018
  • Rapid industrial growth based on massive fossil fuel energy consumption has caused serious damages on natural environment and every aspects of human life. As demands for clean and pleasant living circumstance increases, conflicts and disputes around environmental problems have also been widespread. Given the 'environmental rights' is a relatively new legal concept, however, resolving environmental disputes through the traditional legal principles and litigation procedures could be restrictive and, in some sense. inefficient as well as expensive. With efforts to develop new legal principles on environmental disputes, the environmental dispute adjustment system has been introduced as an alternative dispute resolution to the traditional legal dispute procedures. The Korean Environmental Dispute Resolution Commission introduced as the environmental dispute adjustment system has been well established for the past twenty-seven years, given the steadily increasing numbers of applications to the Commission over environmental disputes. However, as most cases are still small in money terms and mainly subject to adjudication, the effectiveness and practical contribution of the Commission in the resolution of environmental disputes have in fact been limited. For the enhancement of the status and roles of the Commission as the prior instrument of the alternative dispute resolution(ADR) in environmental disputes, several suggestions could be considered as follows: First, mediation needs to be more activated than adjudication in order to meet the primary purpose of ADR that resolves environmental disputes according to free will of concerned parties. Second, the scope of mediation could be expanded to the areas including potential environmental damages. Third, the roles and responsibilities of the Environmental Dispute Resolution Commissions at both central and local levels need to be evenly distributed. Fourth, the mechanism and procedures of environmental dispute resolution should be standardized. Fifth, the status of the Environmental Dispute Resolution Commission could be elevated in rank by shifting its current affiliation from the Ministry of Environment to the Office of Prime Minister. Sixth, the organizational structure and human resources of the Commission need to be reinforced. Seventh, the current situation that tends to give priority to litigation procedures when an environment dispute is simultaneously pending in litigation and mediation should be eased and properly adjusted. Eighth, the adoption of mandatory mediation in advance to litigation needs to be discussed. Ninth, the legal authority of the Commission's decisions should be further guaranteed. If above suggestions are thoroughly reviewed and properly adopted, the roles, authority and power of the Environmental Dispute Resolution Commission would be increased in the era when environmental conflicts get widespread, requiring an effective alternative environmental dispute resolution mechanism.

The Effect of Coal Particle Size on Char-$CO_{2}$ Gasification Reactivity by Gas Analysis (가스분석을 이용한 석탄 입자크기가 촤-$CO_{2}$ 가스화 반응성에 미치는 영향 연구)

  • Kim, Yong-Tack;Seo, Dong-Kyun;Hwang, Jung-Ho
    • Korean Chemical Engineering Research
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    • v.49 no.3
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    • pp.372-380
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    • 2011
  • Char gasification is affected by operating conditions such as reaction temperature, reactants gas partial pressure, total system pressure and particle size in addition to chemical composition and physical structure of char. The aim of the present work was to characterize the effect of coal particle size on $CO_{2}$ gasification of chars prepared from two different types of bituminous coals at different reaction temperatures(1,000-$1,400{^{\circ}C}$). Lab scale experiments were carried out at atmospheric pressure in a fixed reactor where heat was supplied into a sample of char particles. When a flow of $CO_{2}$(40 vol%) was delivered into the reactor, the char reacted with $CO_{2}$ and was transformed into CO. Carbon conversion of the char was measured using a real time gas analyzer having NDIR CO/$CO_{2}$ sensor. The results showed that the gasification reactivity increased as the particle size decreased for a given temperature. The sensitivity of the reactivity to particle size became higher as the temperature increases. The size effects became remarkably prominent at higher temperatures and became a little prominent for lower reactivity coal. The particle size and coal type also affected reaction models. The shrinking core model described better for lower reactivity coal, whereas the volume reaction model described better for higher reactivity coal.

A Study on Inflow Rate According to Shape of Dual Structure Perforated Pipe Applied to Seawater Intake System (해수취수시스템에 적용된 2중구조 유공관의 형태에 따른 취수효율에 대한 연구)

  • Kim, Sooyoung;Lee, Seung Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.6
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    • pp.721-728
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    • 2016
  • 97% of water on earth exists in the form of seawater. Therefore, the use of marine resources is one of the most important research issues at present. The use of seawater is expanding in various fields (seawater desalination, cooling water for nuclear power plants, deep seawater utilization, etc.). Seawater intake systems utilizing sand filters in order to take in clean seawater are being actively employed. For the intake pipe used in this system, assuring equal intake flows through the respective holes is very important to improve the efficiency of the intake and filtering process. In this study, we analyzed the efficiency of the dual structure perforated pipe used in the seawater intake system using 3D numerical simulations and the inflow rate according to the gap of the up holes. In the case of decreasing gaps in the up holes toward the pipe end, the variation of the total inflow rate was small in comparison with the other cases. However, the standard deviation of the inflow rate through the up holes was the lowest in this case. Also, stable flow occurred, which can improve the efficiency of the intake process. In the future, a sensitivity analysis of the various conditions should be performed based on the results of this study, in order to determine the factors influencing the efficiency, which can then be utilized to derive optimal designs suitable for specific environments.

A Study on the Characteristics of Logos in Inner Wear Brand (이너 웨어(Inner Wear) 로고의 특성에 관한 연구)

  • Lee, Min-Gyung;Rha, Soo-Im
    • The Research Journal of the Costume Culture
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    • v.14 no.5
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    • pp.790-801
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    • 2006
  • This study analyzed features of elements that compose a logo of inner wear brands to get the following results: First, it was found that "elegance" was the most frequently used word to express the concept of inner wear brands to be followed by words like dignity, high-end and aristocratic, words emphasizing femininity, such as feminine, romantic and sexy, words emphasizing practicality, such as convenient, practical, modern, functional and reasonable, and words emphasizing hygiene, such as clean, healthy and hygienic. This suggests that consumers nowadays pursue image more than functional aspects in the shopping of inner wear and consumers' pursuit of such values is reflected in the concept of inner wear brands. Second, unlike logos for outerwear brands that generally used initials of brand name, word-type logos for inner wear brands used the full name of brands, thus suggesting that they put more emphasis on delivery of information rather than on the symbolic aspect. In case of combining characters with concrete objects, they were found generally to use objects that give an soft, elegant and feminine image, such as flowers, woman's head and ribbons. Third, colors in the series of pink and red seemed to be used to convey the concept of inner wear brands that pursue such images as romanticism, femininity, elegance and sensibility, while colors in the series of blue, black and grey for such concepts as functionality, practicality, simplicity, health, hygiene and refinement. With reference to typeface used in the design of logos, unlike outerwear brands of which 83% use sans serif typeface for logos, relatively high percentage of inner wear was found to use typefaces of serif series to stress feminine flexibility and delicacy and give the image of elegance and classical tenderness. With reference to language used in logo naming for inner wear brands, 33 brands were found to use English and only three brands used Korean among the 36 brands surveyed. Even with inner wear brand logos that have Korean name, it was found that they used English in the use of logo marks. Like the result of previous studies, the result of this study indicates that methods to design brand logos for clothing should be incessantly sought in a way to build brand power as an important component to represent concept or function of brands and reinforce brand image.

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Brief Review of Silicon Solar Cells (실리콘 태양전지)

  • Yi, Jun-Sin
    • Journal of the Korean Vacuum Society
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    • v.16 no.3
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    • pp.161-166
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    • 2007
  • Photovoltaic (PV) technology permits the transformation of solar light directly into electricity. For the last five years, the photovoltaic sector has experienced one of the highest growth rates worldwide (over 30% in 2006) and for the next 20 years, the average production growth rate is estimated to be between 27% and 34% annually. Currently the cost of electricity produced using photovoltaic technology is above that for traditional energy sources, but this is expected to fall with technological progress and more efficient production processes. A large scale production of solar grade silicon material of high purity could supply the world demand at a reasonably lower cost. A shift from crystalline silicon to thin film is expected in the future. The technical limit for the conversion efficiency is about 30%. It is assumed that in 2030 thin films will have a major market share (90%) and the share of crystalline cells will have decreased to 10%. Our research at Sungkyunkwan University of South Korea is confined to crystalline silicon solar cell technology. We aim to develop a technology for low cost production of high efficiency silicon solar cell. We have successfully fabricated silicon solar cells of efficiency more than 16% starting with multicrystalline wafers and that of efficiency more than 17% on single crystalline wafers with screen printing metallization. The process of transformation from the first generation to second generation solar cell should be geared up with the entry of new approaches but still silicon seems to remain as the major material for solar cells for many years to come. Local barriers to the implementation of this technology may also keep continuing up to year 2010 and by that time the cost of the solar cell generated power is expected to be 60 cent per watt. Photovoltaic source could establish itself as a clean and sustainable energy alternate to the ever depleting and polluting non-renewable energy resource.

The Effect on Firm's Performance of Employee Stock Option (종업원의 주식보상시스템이 기업성과에 미치는 영향)

  • Park, Jong-Hyuk
    • Management & Information Systems Review
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    • v.28 no.1
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    • pp.71-97
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    • 2009
  • In this study, I compare the ability of alternative accounting method for employee stock option to reflect firm value using the Ohlson's(1995) valuation model for 200 firms. The each methods, I compare are employee stock option expense recognition based on the K-GAAP disclosures, and asset recognition at the grant date based on the SFAS No. 123 Exposure Draft: Accounting for stock-based compensation. The model include: (1) a model that uses reported earnings, equity book value, and compensation expense based on the K-GAAP disclosures; (2) a model that uses pro-forma earnings, equity book value and adds a measure of the unrecognized asset arising form granting of employee stock options. Finding form estimating equations that the K-GAAP method for calculating compensation has no explanatory power, and the SFAS No.123 Draft Exposure method for arising asset and fair value compensation better captures than market's perception of the economic impact of stock options on firm values. However, the correlation of employee stock option compensation expense is positive. These results suggest that incentive benefits derived from employee stock option plans outweigh the cost associated with plan. In addition, I couldn't find evidence that company in KOSDAQ that have high growth potential benefit more from employee stock option plan compared to lager, more mature firm in SEC.

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Effect of New Mattress System with Vegetation Base Materials on the Vegetation Coverage of Stream bank (계안 복원을 위한 매트리스형 식생기반재 돌망태 공법의 계안사면 피복효과)

  • Choi, Hyung Tae;Jeong, Yong-Ho;Park, Jae-Hyeon
    • Journal of Korean Society of Forest Science
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    • v.101 no.2
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    • pp.175-184
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    • 2012
  • This study was conducted to develop new mattress systems with vegetation base materials for protecting stream bank and rapid rehabilitation. Vegetation base materials are primarily compounded with fine soil, organic composts and peat moss as plant fibers, a water retainer and a soil improver. Peat moss can usually provide necessary natural fibers and organic materials in soil. Especially, peat moss can absorb up to 25 times its own weight in water and is therefore valued as a water retainer to prevent drying effect of vegetation base materials which can harm the growth of vegetation in mattresses. Normally mattress systems resist the lateral earth pressures or stream power by their own weight. Therefore, filled materials must have suitable weight, compressive strength and durability to resist the loading, as well as the effects of water and weathering. In this project, 100 to 200-mm clean, hard stones were basically specified, and about 50-mm rubbles were also used. Test application of new mattress system carried out in the stream bank of a small stream in the Gwangreung experimental forest, belonging to Korea Forest Research Institute (KFRI) in December 16th, 2006. As a result of the monitoring of vegetation coverage of test application plots (each plot size is 4 by 2 m), the coverage of all plots reached 100% in the end of May, 2007 (approximately 50 days passed after the first gemination of vegetation). The coverage of the plots using big hard stones and organic composts and the plots containing peat moss increased more rapidly. The results show that peat moss is effective to retain soil moisture and establish more sound environment for vegetation gemination.

The Co-Combustion Characteristics of Coal and Wood Pellet in a 25W Lab-scale Circulating Fluidized Bed Reactor (25W급 순환유동층반응기에서 석탄과 우드펠릿의 혼소 특성 연구)

  • Kim, Jin Ho;Yang, Sang Yeol;Kim, Gyu Bo;Jeon, Chung Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.8
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    • pp.683-691
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    • 2015
  • Circulating Fluidized Bed(CFB) combustion has the several advantages which are the fuel flexibility, the economy, the efficiency and the environment. It is necessary to apply a renewable energy to produce electricity due to the Renewable Portfolio Standard(RPS) mandates recently. So, in this study, co-combustion with a coal and a wood pellet was investigated to evaluate the combustibility and the environment as function of blending ratio of them in a Lab-scale CFB reactor. To investigate the characteristics of the co-combustion, the blending ratio which is the weight of wood pellet by the total calorific value of the supplied, was considered. Bed material was a river sand(No. 7). As increasing the blending ratio, the exhausted gas emissions such as CO, NOx, HC and SOx were decreased. But in case of wood pellet over 30%, CO, HC and SOx emission were increased. And the gas temperatures at the downstream were decreased.

Experimental Investigation into the Combustion Characteristics on the Co-firing of Biomass with Coal as a Function of Particle Size and Blending Ratio (바이오매스(우드펠릿) 혼소율 및 입자크기에 따른 연소 특성에 관한 연구)

  • Sh, Lkhagvadorj;Kim, Sang-In;Lim, Ho;Lee, Byoung-Hwa;Kim, Seung-Mo;Jeon, Chung-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.1
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    • pp.31-37
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    • 2016
  • Co-firing of biomass with coal is a promising combustion technology in a coal-fired power plant. However, it still requires verifications to apply co-firing in an actual boiler. In this study, data from the Thermogravimetric analyzer(TGA) and Drop tube furnace(DTF) were used to obtain the combustion characteristics of biomass when co-firing with coal. The combustion characteristics were verified using experimental results including reactivity from the TGA and Unburned carbon(UBC) data from the DTF. The experiment also analyzed with the variation of the biomass blending ratio and biomass particle size. It was determined that increasing the biomass blending ratio resulted in incomplete chemical reactions due to insufficient oxygen levels because of the rapid initial combustion characteristics of the biomass. Thus, the optimum blending condition of the biomass based on the results of this study was found to be 5 while oxygen enrichment reduced the increase of UBC that occurred during combustion of blended biomass and coal.