• Journal of Advanced Marine Engineering and Technology
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• 제33권3호
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• pp.373-377
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• 2009

It is well known that SOx and NOx concentration has a considerable influence on the $N_2O$ emission of the greenhouse gas properties. The quantity of SOx generated during combustion, on fuel specific basis, is directly related to the sulfur content of the fuel oil. However, restricting the fuel oil sulfur content is only a partial response to limiting the overall quantity of SOx emissions, as there remains no over control on the fuel oil consumption other than the commercial pressure which have always directed the attention. This study was carried out as a new basic experiment method of emission control, manly targeted to the vessel. In the experiment, where the scrubbing was achieved through spray tower with high alkaline water made from the electrolysis of seawater, the combined action was to neutralize the exhaust gases (SOx, PM, CO etc.), dilute it, and wash it out. The results showed that SOx reduction of around 95 percent or over could be achieved when using in the high alkaline water, and also leaded to a reduction in the stability of the each pollutant components including the PM (Particulate Matter). The results suggest that the seawater electrolysis method has a very effective reduction of emissions without heavy cost, or catalysts particularly on board.

• 동력기계공학회지
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• 제17권1호
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• pp.27-35
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• 2013

SCR (Selective Catalytic Reduction) on DPF (Diesel Particulate Filter) is a multi-functional after-treatment device which integrates soot filtration and DeNOx function into a single can. Because of its advantage in package and cost, the SCR on DPF is considered as a potential candidate for future application. It inherently employes wall flow type monolithic reactor so ash included in exhaust gas may deposit inside the inlet channel of this device. This study is intended to identify the impact of ash deposit on SCR reaction under wall flow type monolithic reactor. Simulation approach is used so relevant species transport equations for wall flow type monolith is derived. These equations can be solved together with momentum conservation equations and give solution for conversion performance. Both ash deposit and clean catalyst case are simulated and comparison of these two cases gives an insight for the impact of ash deposit on conversion performance. Ash deposit can be classified as ash layer and ash plug. and impact of ash deposit is described along with different morphology of ash deposit.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1615-1622
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• 2010

Recently, there has been an increase in interest from the aspects of transshipment and connection between the means of transportation. Not only for passengers but also for freight transportation as the need for transportation efficiency is growing while the importance of logistic railway transportation is emerging. The domestic freight transportation is carried out by roads, railroads, ships, and port. However, as other means of transportation, except road, is impossible for Door to Door Service, multimodal transportation accompanied by road transportation is carried out. Here, even though 'transshipment' occurs, because of the lack of basic data regarding this, it is difficult to reflect it in the demand forecasting. With respect to the Korean freight O-D, it was very difficult to have equivalent comparison on the competitiveness and availability of transportation services between the point of departure and the final destination. Taking into account the study of implementation of logit model considering the time and cost of transshipment of multimodal transportation and the transshipment resistance value upon selecting means of freight transportation on multimodal transportation was comparatively insufficient. This study consisted of questionnaire targeting shippers, and based on this, transshipment resistance value was calculated by deriving utility function. By doing so, I intend to examine the effect 'transshipment' has on selecting the means of transportation occurring from freight transportation.

• 한국도로학회논문집
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• 제19권3호
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• pp.83-90
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• 2017

PURPOSES : In this study, systematic road snow-removal capabilities were estimated based on previous historical data for road-snowremoval works. The final results can be used to aid decision-making strategies for cost-effective snow-removal works by regional offices. METHODS : First, road snow-removal historical data from the road snow-removal management system (RSMS), operated by the Ministry of Land, Infrastructure and Transport, were employed to determine specific characteristics of the snow-removal capabilities by region. The actual owned amount and actual used amount of infrastructure were analyzed for the past three years. Second, the regional offices were classified using K-means clustering into groups "close" to one another. Actual used snow-removal infrastructure was determined from the number of snow-removal working days. Finally, the correlation between the de-icing materials used and infrastructure was analyzed. Significant differences were found among the amounts of used infrastructure depending on snowfall intensity for each regional office during the past three years. RESULTS:The results showed that the amount of snow-removal infrastructure used for low heavy-snowfall intensity did not appear to depend on the amount of heavy snowfall, and therefore, high variation is observed in each area. CONCLUSIONS:This implies that the final analysis results will be useful when making decisions on snow-removal works.

• 한국주거학회논문집
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• 제26권5호
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• pp.113-121
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• 2015

Several housing improvement programs for low-income have done by Ministry of Health & Welfare, Ministry of Trade, Industry & Energy, Ministry of Security and Public Administration, Ministry of Environment, and Ministry of Land, infrastructure and Transport up to now. Each program practiced separately based on each agency's function and territory, but there are also negative opinion on beneficiary duplication, beneficiary omission, and the inefficient execution of the government budget. This study analyzes the housing improvement programs of each agency on the aspects of coordination, and suggests the integration system with coordination and delivery system. We selected 3 indexes such as similarity, integration effect and availability for integration system and analyzed the effects of integrated programs into one based on cost, repair effect and management. We proposed that the similar housing improvement programs of each agency should be coordinated for integration. But it is not easy to integrate similar programs into one program, therefore similar programs which support the house owner are needed to integrate into housing benefit except same beneficiary who owned own house.

• 무역상무연구
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• 제75권
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• pp.49-69
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• 2017

Making a international contract of sale is not a simple work. International Trade parties(seller and buyer) may choose trade terms such as FOB or CIF to simplify their contracts and avoid misunderstanding of international commercial practice. Incoterms is the international rules for the interpretation of the trade terms, and firstly regulated by the ICC in 1936. The latest version is Incoterms 2010. Incoterms 2010 governs certain responsibilities between the seller and the buyer under the international contract of sale. Moreover, Incoterms 2010 provides the standard of division of costs relating to contract of carriage. But we should note that Incoterms 2010 is not the part of contract of carriage. The writer points out that there is no consistence principle in distributing the special costs under the contract of carriage like unloading cost from the transport vehicle. To avoid the dispute between the parties, it is more safe for international traders to fully and completely understand on the customs and practice of carriage of goods. Incoterms 2010 provides more detailed method of delivery of goods than CISG and RAFTD. Concerning the method of delivery of goods, CISG and RAFTD simply provide that the seller shall place the goods at the discharge of buyers. The writer suggests the basic principles to allocate the special costs of delivery of goods according to the trade terms under Incoterms 2010.

• 통상정보연구
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• 제10권1호
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• pp.97-115
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• 2008

This paper is to review how Korean trading companies perform and promote the digital transformation through the e-networking with global market, and how much they extend the volume of export, and make the company grow inward or outward in order to enhance the effects of economic growth in Korea. It is suggested that global agreement on e-Trade(or u-Trade) should be made in order to expand the global e-networking practices and to ensure transferring of transport documents(or business documents). Moreover, it also suggested that networking on the global trading partners such as government authorities, diplomatic offices abroad, overseas Koreans, students studying abroad, Korean merchants abroad, etc. should be made in single window for improving and upgrading the image of Korean trading companies. By making of global e-network platform between overseas business partners, trading companies are able to expect various synergy effects such as improving the satisfaction of their customers, promoting the global transactions, reducing the operation and transaction cost, helping fording overseas buyers, and extending export volume and sales profit, etc. Customers can also obtain the information about trading goods easily and rapidly, and cut down the transaction stage using information exchange with partners. All of the trading partners in the world can maintain their business partnership as long as they use the global e-network.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.464.1-464.1
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• 2014

Among numerous material candidates, Cu(InxGa1-x)(SySe2-y) (CIGS) thin films have emerged as promising material candidates for thin film solar cell applications due to the high energy conversion efficiency and relatively low fabrication cost. The CIGS thin film solar cells consist of several materials, including Mo back contacts, ZnO-based window layers, and CdS buffer layers. All these materials have different crystal structures and contain quite distinct chemical elements, and hence the device characterization requires careful analyses. Most of all, identification of the major trap states resulting in the carrier recombination processes is a key step toward realization of high efficiency CIGS solar cells. We have carried out electrical investigations of CIGS thin film solar cells to specify the major trap states and their roles in photovoltaic performance. In particular, we have used the temperature-dependent transport characterizations and admittance spectroscopy. In this presentation, we will introduce some exemplary studies of DC and AC electrical characteristics of the CIGS solar cells.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.134.2-134.2
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• 2014

Photonic crystal solar cells have the potential for addressing the disparate length scales in polymer photovoltaic materials, thereby confronting the major challenge in solar cell technology: efficiency. One must achieve simultaneously an efficient absorption of photons with effective carrier extraction. Unfortunately the two processes have opposing requirements. Efficient absorption of light calls for thicker PV active layers whereas carrier transport always benefits from thinner ones, and this dichotomy is at the heart of an efficiency/cost conundrum that has kept solar energy expensive relative to fossil fuels. This dichotomy persists over the entire solar spectrum but increasingly so near a semiconductor's band edge where absorption is weak. We report a 2-D, photonic crystal morphology that enhances the efficiency of organic photovoltaic cells relative to conventional planar cells. The morphology is developed by patterning an organic photoactive bulk heterojunction blend of Poly(3-(2-methyl-2-hexylcarboxylate) thiophene-co-thiophene) and PCBM via PRINT, a nano-embossing method that lends itself to large area fabrication of nanostructures. The photonic crystal cell morphology increases photocurrents generally, and particularly through the excitation of resonant modes near the band edge of the organic PV material. The device performance of the photonic crystal cell showed a nearly doubled increase in efficiency relative to conventional planar cell designs. Photonic crystals can also enhance performance of other optoelectronic devices including organic laser.

• Environmental Engineering Research
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• 제25권4호
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• pp.605-613
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• 2020

This study is to investigate the possibility of using activated carbon prepared from Iraqi date-pits (ADP) which are produced from palm trees (Phoenix dactylifera L.) as low-cost reactive material in the permeable reactive barrier (PRB) for treating lead (Pb⁺²) from the contaminated groundwater, and then compare the results experimentally with other common reactive materials such as commercial activated carbon (CAC), zeolite pellets (ZP). Factors influencing sorption such as contact time, initial pH of the solution, sorbent dosage, agitation speed, and initial lead concentration has been studied. Two isotherm models were used for the description of sorption data (Langmuir and Freundlich). The maximum lead sorption capacities were measured for ADP, CAC, and ZP and were found to be 24.5, 12.125, and 4.45 mg/g, respectively. The kinetic data were analyzed using various kinetic models particularly pseudo-first-order, pseudo-second-order, and intraparticle diffusion. COMSOL Multiphysics 3.5a depend on finite element procedure was applied to formulate transmit of lead (Pb⁺²) in the two-dimensional numerical (2D) model under an equilibrium condition. The numerical solution shows that the contaminant plume is hindered by PRB.