• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.123-133
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• 2021

This research aims to examine the effect of carbon emission disclosure on firm value and to reveal environmental performance and industrial type as the moderating variables. This study used 82 samples of companies listed on the Indonesia Stock Exchange (IDX) and receiving awards in the Indonesian Sustainability Reporting Award (ISRA) in 2014-2018. This study used a multiple linear regression analysis to test the hypotheses. The results showed that carbon emission disclosure had a positive and significant effect on firm value as carbon emission disclosure is a form of corporate concern on environment positively responded by the market and becomes the basis for investors to make their considerations in assessing the company sustainability. Besides, environmental performance and industrial type can strengthen the influence relationship of carbon emission disclosure on firm value since environmental performance was assessed based on ISO 14001 certification ensuring that the company has tried to preserve the environmental sustainability by creating a good environmental management system. Moreover, companies categorized into high profile industrial type have tried to change their unfavorable image and avoid lawsuits by performing carbon emission disclosure to gain positive responses from the market.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.6
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• pp.43-50
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• 2010

In this paper, we analyzed radiated emission generated by the split power/ground plane structures in order to reduce EMI in system modules. The magnetic fields and electric fields were simulated and measured on the test boards under various conditions. In order to reduce radiated emission, we have to determine spacing and location of the split ground gap so that input signal frequency does not coincide with the resonance frequency of the split power/ground plane structure and the phase of reflection coefficient is close to $0^{\circ}$ at input signal frequency. Moreover, we found that inserting a stitching capacitor could reduce the radiated emission. Low magnitude of reflection coefficient and the phase close to $0^{\circ}$ are required to reduce radiated emission. It is necessary to properly decide value and location of a stitching capacitor to fulfil those requirements.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.191-206
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• 2018

In this study, the HAPs(Harzard Air Pollutants) emission factor level of Starex and Grand Carnival was tested using PEMS (Portable Emissions Measurement System) on real road driving. As a result of RDE (Real Driving Emission test), the overall vehicle speed pattern showed similar characteristics. The real-road driving test at constant speed revealed emission factor is inversely proportional relationship to constant speed. Results of accelerating with speed limit on the real-road were shown as followings; Uran (less than 45 km/h)>Rural (<45 km/h, less than 80 km/h)>Motorway (>80 km/h). Moreover, the sudden acceleration and deceleration in driving at high speed was the increasing factor to the HAPs emission factor. This tendency is considered to be influenced by the operating environment on real roads.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.5
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• pp.309-317
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• 2000

Demand for new nondestructive evaluations is growing to detect tensile crack growth behavior to predict long term performance of materials and structure in aggressive environments, especially when they are in non-visible area. Acoustic emission technique is well suited to these problems and has drawn a keen interests because of its dynamic detection ability, extreme sensitivity and location of growing defects. In this study, we investigated the strength of fire resistance steel for frame structure by tensile test after degradation treatment and analysed acoustic emission signals obtained from tensile test with time frequency analysis methods. In the T and TN specimens(under $600^{\circ}C$-10min ) consisting of ferrite and pearlite structure, most of acoustic emission events were produced near yield point, mainly due to the dislocation activities during the deformation. However, B specimen under $600^{\circ}C$-10min had a two peak which was attribute to the presence of martensite phase. The first peak is before yield point and the second after yield point. The sources of second acoustic emission peak were the debonding of martensite-martensite interface and the micro-cracking of brittle martensite phase. In $600^{\circ}C$-30min to $700^{\circ}C$-60min, many signals were observed before yield point and were decreased after yield point.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.1
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• pp.68-76
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• 2012

SULEV (Super Ultra Low Emission Vehicle) which is one of the emission standards in Fleet Average System introduced to Korea from 2009 is known as the most severe standard to achieve with internal combustion engine. Considering low sales volume of hybrid vehicles in Korea, vehicle manufacturers are required to develop SULEV technologies for conventional gasoline and LPG vehicles to meet the future Fleet Average standard. In this study, the comparison of emissions has been made between SULEV developed and ULEV LPG vehicles mainly produced in this time. To estimate the emission reduction of SULEV vehicles, CVS-75 and NIER test modes have been used. CVS-75 has been used for emission certification of gasoline and LPG vehicles. NIER modes cover various average vehicle speed and reflect Korean real driving patterns better than CVS-75. The test results show that SULEV LPG vehicles have very high potential to reduce $NO_x$ in regulated emissions, $N_2O$ in green house gases and toluene in VOCs. However, SULEV LPG vehicles don't affect much on the reduction of CO and total green house gases.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3335-3340
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• 2007

The government have been tightening EM regulation gradually but the effect is not good because of rapid increase of vehicles. And medium & heavy duty diesel vehicles, even though the number is small, exhaust very large pollutants(about over 50%). Especially it is more severe about old trucks and buses. Accordingly, CNG vehicle and the retrofit of diesel to CNG must be an alternative in order to protect the atmospheric environment and improve the air quality in the metropolitan area. The main object of this study is to secure the retrofit technology of diesel to CNG vehicle and the management system of CNG engine. we passed the government emission certification test. In addition to this, the mass production for retrofit is also studied. Results of emission and durability test for certification are as follows; there was no problem during 30,000km vehicle durability test and good emission levels satisfying the regulation.

• Journal of ILASS-Korea
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• v.23 no.4
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• pp.234-243
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• 2018

Since September 2017, a small diesel vehicle certification test mode has been enhanced from NEDC to WLTC. The main reason for the change of the certification test mode is that the certification test mode of the emission control standard of the diesel vehicle does not sufficiently reflect various driving patterns of the actual roads. Several automakers have developed after-treatment systems such as LNT, SCR, and DPF to meet enhanced emissions regulations. In this study, four small diesel cars were selected for sale in Korea, and the exhaust gas measurement test was performed in the WLTC mode, which reflects the driving characteristics of the actual roads. As a result of test, LNT vehicle exceeded Euro 6 NOx regulation and SCR vehicle satisfied Euro 6 NOx regulation. In addition, both LNT and SCR systems showed high NOX emission characteristics due to speed, RPA and Vxa. For the PN, all test vehicles were fitted with a DPF and met the Euro 6 PN regulations, with similar PN emissions results in LNT and SCR system.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.3
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• pp.276-285
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• 2010

Recently the Korean government has tried to cut down the $PM_{10}$ concentration by the Special Law for Air Quality Improvement. But the concentrations of $PM_{10}$ have exceeded the air quality standard at most monitoring stations. Primary $PM_{10}$ emitted from various sources and emission data have large uncertainty. The biomass burning is one of the major sources of $PM_{10}$ emission. The biomass burning is composed of wood stove usage, meat cooking and agricultural combustion etc.. Activity data and emission factors for the biomass burning are limited, and it is hard to calculate the air pollution emissions from these sources. In this study, we tried to estimate the air pollution emission from residential wood stove usage. The number of total wood stoves is estimated by the survey of wood stove manufacturer. And air pollution emission factors for the wood stove are investigated using the flue gas measurement by U.S. EPA particulate test method (Method 5G). As the results, the $PM_{10}$ and CO emission factors of wood stove are estimated as 7.7 g/kg-wood and 78.8 g/kg-wood respectively. The annual $PM_{10}$ and CO emissions from wood stove are calculated as 1,200~3,600 ton/year and 12,600~36,400 ton/year in Korea. It is confirmed that wood stove is the one of major sources of biomass burning, and the survey for activity data and the measurement for emission factors are needed for reducing the uncertainty of these emission data.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.4
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• pp.539-553
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• 2004

Up to the present time, many methods to estimate emissions from a particular diesel engines have wholly depended on the quantity of diesel fuel consumed. Then, the recommended emission factors were normalized by fuel consumption, and further total activity was estimated by the total fuel consumed. One of main purposes in the study is newly to develop emission factors for the railroad diesel rolling stock (RDRS) and to estimate a total amount of major gaseous pollutants from the RDRS in Korea. Prior to develop a Korean mode emission factor. the emission factor from the USEPA was simply applied for comparative studies. When applying the USEPA emission factors, total exhaust emissions from the RDRS in Korea were estimated by 28,117tons of NOx, 2,832.3tons of CO, and 1,237.5tons of HC, etc in 2001. In this study, a emission factor for the RDRS, so called the KoRail mode (the Korean Railroad mode) has been developed on the basis of analyzing the driving pattern of the Gyeongbu-Line especially for the line-haul mode. Explicitly to make the site specific emission factors, many uncertainty problems concerning weighting factors for each power mode, limited emission test, incomplete data for RDRS, and other important input parameters were extensively examined. Total exhaust emissions by KoRail mode in Korea were estimated by 10,960tons of NOx, and 4,622tons of CO, and so on in the year of 2001. The emissions estimated by the USEPA mode were 2.6 times higher for NOx, and 1.6 times lower for CO than those by the KoRail mode. As a conclusion, based on the emission calculated from both the USEPA mode and the KoRail mode, the RDRS is considered as one of the significant mobile sources for major gaseous pollutants and thus management plans an(1 control strategies for the RDRS must be established to improve air quality near future in Korea.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.2
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• pp.184-192
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• 2001

In this paper, we analyze the result of the conduced emission and susceptibility tests performed on the KOMPSAT-I ETB Platform. The ETB platform consists of the EM (Engineering Model) boxes developed to perform the electrical functional test. During the conducted emission test, we measured the instant waveform in time domain when each switch was turn on, and spectrum of the noise in the frequency range of 10 Hz up to100 MHz fur the steady state of the ETB. During the conducted susceptibility test, no malfunction and no serious damage of the electronic box were observed when a simulated noise waveform was applied to the DC power bus. The simulated waveform was obtained by adding the 6 dB-system margin to the worst case waveform measured from the conducted emission. This test was performed as co-development of the KOMPSAT-I with TRW in USA.