• Transactions of the Korean Society of Automotive Engineers
• /
• v.12 no.1
• /
• pp.61-65
• /
• 2004

This paper presents the effect of methanol blended fuel on the engine performance and the reduction of exhaust emissions. In this wort, the combustion effects of methanol blended fuel in the engine was investigated for the conditions of three kinds of mixing ratios. Based on the experimental results, the output characteristics of the engine show the improvement of output performance due to the blended fuel of methanol. Also, the unburned hydrocarbon and carbon monoxide emissions are decreased in accordance with the increase of methanol blended ratio.

• Journal of Korean Society of Forest Science
• /
• v.103 no.1
• /
• pp.137-146
• /
• 2014

We have developed the Forest Carbon Sink Index on afforestation and reforestation activities, a regulation stated in article 26 of the 'Law on the maintenance and enhancement of carbon sink (Carbon Sink Law)', which took effect on March, 2013. According to the legal purpose to evaluate the performance of individual forest carbon offset projects and to compare each other at a certain point, values of the forest carbon sink index were calculated by the scoring method. Three criteria were established based on the Carbon Sink Law: 'Carbon' (real greenhouse gas reduction), 'Human' (socio-economic effect) and 'Nature' (environmental effect). Continuously, 9 indicators from the three criteria were selected by top-down approach; the adequacy of each criteria and indicators were reviewed through on-line Delphi survey; and finally weighted value of each criteria and indicators were assigned. To reflect the characteristics of the domestic forest carbon offset projects, which focus on corporate social responsibility-typed projects, we applied the score weighting method to minimize gaps among criteria and ones among indicators. After applying our newly developed forest carbon sink index to five domestic forest carbon offset projects, we could confirm that the criteria of 'Human' and 'Nature', which criteria are in relatively low weight, can play a role as an actual incentive to reduce negative socio-economic and environmental impacts. Based on performance evaluation of the five forest carbon offset project by the forest carbon sink index, the best or good performance project developers could be rewarded, and further the performance evaluation would work as an incentive to stimulate the involvement of domestic project developers in the field of forest carbon offset project.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.5
• /
• pp.213-218
• /
• 1997

CNG dual fuel engine for heavy duty diesel engine has been equipped to a Korean bus engine and tested to compare th engine performance and the emission characteristics with the existing diesel fueled engine. The results are summarized as follows. Diesel fueled engine has the fuel injection timing of BTDC17°. The injection timing of CNG modified engine is retarded to BTDC14° for reduction of NOx. Performance optimization has been carried out to have engine power equivalent to or better than the diesel fueled engine. Smoke is decreased by 85% by Korean smoke 3 mode test. By 6 mode test CO is increased by 313% and THC is increased by 1407%. NOx is decreased by 27%. Even though THC is increased very much, it's not too serious problem since CO and THC emission of diesel engine are very little compared to gasoline engine and THC don't give bad effect on human health. But the reduction technologies of CO and THC need to be considered.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.159-159
• /
• 2009

In this work, nitrogen and oxygen functionalities was introduced to the graphite nanofibers (GNFs) and their effect on electrocatalytic performance of the GNF supports for direct methanol fuel cells (DMFCs) was invesigated. The nitrogen and oxygen groups were introduced through the urea treatments and acid treatment, respectively. And, PtRu catalysts deposited on modified GNFs were prepared by a chemical reduction method. The catalysts were characterized by means of elemental analysis, nitrogen adsorption, and X-ray photoelectron spetroscopy (XPS). The structure and morphological characteristics of the catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). As a result, the Pt-Ru nanoparticles were impregnated on GNFs with good formation in 3-5 nm. And, the cyclic voltammograms for methanol oxidation revealed that the methanol oxidation peak varied depending on changes of surface functional groups. It was thus considered that the PtRu deposition was related to the reduction of PtRu and surface characteristics of the carbon supports. The changes of surface functional groups were related to PtRu reduction, significantly affect the methanol oxidation activity of anode electrocatalysts in DMFCs.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.42 no.1
• /
• pp.158-166
• /
• 2019

In pursuing carbon emission reduction efforts, companies have focused for the most part on reducing emissions due to the more efficient equipment and facilities. However they overlook a significant source of carbon emissions, one that is driven by operational policies. Currently companies are looking for solutions to reduce carbon emissions associated with their operations. Operational adjustments, such as modifications in order quantities could an effective way in reducing carbon emissions in the supply chain. Also, Cap-and-Trade mechanism is generally accepted as on of the most effective market-based mechanism to reduce carbon emissions. In this paper, we investigate a supply chain with single manufacturer and multiple retailers multi-product inventory model under the cap-and-trade system incorporating the carbon emissions caused by transportation and warehousing activities. Also, we provide an iterative solution algorithm and derive the common order interval and the number of intervals for each product. We show by numerical example that the inventory model incorporating cap & trade mechanism can reduce total cost and carbon emissions compared to the classical inventory model. Using the numerical examples, we also investigates different carbon price on the performance of the inventory model.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2961-2964
• /
• 2011

Greenhouse gas and energy reduction goal management system is announced to reduce national CO2 emission in 2011. The target business sector of the system has to follow the procedure of the system and get the assessment. The percentage of the national CO2 reduction goad is 30 % compared to the amounts of BAU. In railway business sector, 6 bodies are included in this system so that railway industry cannot stay and sustain its better position any more than other transportation industry. Most of the industry except Railway industry is struggling to develop its product more environmentally friendly and get the 3rd party certification like Eco-labelling and Carbon footprint. To get environmental certification, LCA method has to be applied because life cycle approach is needed to respond current environmental requirement. The purpose of this project is to facilitate railway vehicle manufacturer obtaining the environmental certification termed Korea EPD. By doing so, the environmental performance evaluation tool would be developed and modelled within the LCA framework and therefore applied especially for rail vehicle.

• Carbon letters
• /
• v.14 no.3
• /
• pp.171-174
• /
• 2013

The high quality contact between graphene and the metal electrode is a crucial factor in achieving the high performance of graphene transistors. However, there is not sufficient research about contact resistance reduction methods to improve the junction of metal-graphene. In this paper, we propose a new method to decrease the contact resistance between graphene and metal using directly grown graphene over a metal surface. The study found that the grown graphene over copper, as an intermediate layer between the copper and the transferred graphene, reduces contact resistance, and that the adhesion strength between graphene and metal becomes stronger. The results confirmed the contact resistance of the metal-graphene of the proposed structure is nearly half that of the conventional contact structure.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.12
• /
• pp.3835-3839
• /
• 2013

A new synthesis route for Pt nanoparticles by direct electrochemical reduction of a solid-state Pt ion precursor ($K_2PtCl_6$) is demonstrated. Solid $K_2PtCl_6$-supported polyethyleneimine (PEI) coatings on the surface of glassy carbon electrode were prepared by simple mixing of solid $K_2PtCl_6$ into a 1.0% PEI solution. The potential cycling or a constant potential in a PBS (pH 7.4) medium were applied to reduce the solid $K_2PtCl_6$ precursor. The reduction of Pt(IV) began at around -0.2 V and the reduction potential was ca. -0.4 V. A steady state current was achieved after 10 potential cycling scans, indicating that continuous formation of Pt nanoparticles by electrochemical reduction occurred for up to 10 cycles. After applying the reduction potential of -0.6 V for 300 s, Pt nanoparticles with diameters ranging from $0.02-0.5{\mu}m$ were observed, with an even distribution over the entire glassy carbon electrode surface. Characteristics of the Pt nanoparticles, including their performance in electrochemical reduction of $H_2O_2$ are examined. A distinct reduction peak observed at about -0.20 V was due to the electrocatalytic reduction of $H_2O_2$ by Pt nanoparticles. From the calibration plot, the linear range for $H_2O_2$ detection was 0.1-2.0 mM and the detection limit for $H_2O_2$ was found to be 0.05 mM.

• Applied Chemistry for Engineering
• /
• v.7 no.5
• /
• pp.999-1005
• /
• 1996

Pt catalyst on carbon black was prepared by colloidal method, ion exchanging method and methanol reducing method. The colloidal method has been used generally. At ion exchanging method, $H^+$ of functional group on carbon surface made by oxidation treatment was exchanged with Pt ion. At methanol reducing method, Pt was impregnated on carbon to reduce by methanol contained with surfactants. With TEM and XRD, Pt particle size impregnated on carbon by various methods was $30{\sim}50{\AA}$. Loading yield was about 100%, loading yield of ion exchanging method was 99.92% by DCP analysis and 99.87% by combustion method. Within 60 hour, current density of oxygen reduction was $460mA/cm^2$ at 0.7V(vs. RHE) at colloidal method. It was the better performance than catalyst prepared by ion exchanging, methanol reducing method. But, it was shown some decrease of performance for long operation time(after 100hour), catalyst prepared by methanol reducing method was shown stable performance.

• Advances in environmental research
• /
• v.7 no.1
• /
• pp.13-28
• /
• 2018

It is currently agreed upon that one of the major challenges in the construction industry is the energy efficiency of existing buildings. The World Meteorological Organisation (WMO) and United Nations (UN) have reported that the concentration of global atmospheric carbon dioxide has increased by an average of 50%, a record speed, from 2015 to 2016. The housing sector contributes to 45% of the UK's carbon emissions. To help tackle some of those issues the recast Energy Performance Building Directive (EBPD) has introduced Nearly Zero Energy Buildings (NZEBs) in the coming years (including buildings that will undergo refurbishment/renovations). This paper will explore the retrofitting of a UK residential dwelling using Thermal Analysis Simulation (TAS, EDSL) software by focusing on building fabric improvements and usage of on-site renewables. The CIBSE Test Reference Year (TRY) weather data has been selected to examine the performance of the building under current and future climate projections. The proposed design variables were finally implemented in the building altogether on TAS. The simulation results showed a reduction in the building's annual energy consumption of $122.64kWh/m^2$ (90.24%). The greatest savings after this were achieved for the annual reduction in carbon emissions and avoided emissions, which were 84.59% and $816.47kg/CO_2$, respectively.