• Journal of the Korean institute of surface engineering
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• v.50 no.5
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• pp.392-397
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• 2017

The Young's modulus of a nanoscale titanium (Ti) thin-film was evaluated using a high-speed microcantilever resonating at the megahertz frequency in the present study. A 350 nm thick Ti film was deposited on the surface of a silicon microcantilever, and the morphology of the film was analyzed using the atomic force microscopy. The microcantilever was excited to resonate using an ultrasonic pulser that generates tone burst signals and the resonance frequency shift induced by the deposition of Ti was measured using a Michelson interferometer. The Young's modulus was determined through a modal analysis using the finite element method and the result was validated by the nanoindentation testing, showing good agreement within a relative error of 1.0%. The present study proposes a nanomechanical characterization technique with enhanced accuracy and sensitivity.

• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.74-85
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• 2013

We analyze the efficiency of congestion pricings and transit subsidies in the spatial micro-economic model based on a general equilibrium environment. In this setting, we decompose the total welfare change into component factors and identify the reason of the change in the efficiency caused by policy instruments; these component factors are divided into indirect factors and direct factors including of origin-destination and mode choices. We set up the model as adding mode choice to the standard format in the fashion of Anas and Kim (1996) and extend the methodology proposed by Yu and Rhee (2011) and Rhee (2012) for deriving theoretical and analytical solution. Most of welfare gain comes from the modal shift from car to bus. The relative efficiency of subsidies in relation to the first-best pricing is lower than it of congestion pricings although the change in bus share by subsidies is similar to it by congestion pricing. Subsidies give rise to more modal shift from a car to a bus for long-distance commuting than it caused by congestion pricings. As the increase of bus share for long-distance commuting leads to the increase of cross-commuters passing through CBD, the welfare gain by subsidies is lower than it by congestion pricings.

• Journal of the Korea Society of Computer and Information
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• v.27 no.1
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• pp.157-166
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• 2022

In this study, The goal is to analyze the feasibility of introducing a Piggyback system that can reduce the time and cost incurred by transshipment work and improve the transportation speed when transporting complex cargo by rail. To this end, the feasibility analysis methodology is reviewed through domestic and international literature review. In order to quantitatively derive the feasibility analysis values, a transportation database was applied to develop a freight transport simulation model and a freight demand prediction model for major freight transport O-D routes with a transportation distance of 200 km or more. As a result of analyzing economic feasibility by setting the analysis period to 15 years on the premise that the Piggyback System will be introduced on major cargo transport O-D routes in 2025, the NPV value was positive and the B/C value was 1.18, indicating that the Piggyback system was economical. The proposed research method can be meaningful data for establishing transportation policies that can improve the competitiveness of railroad transportation.

• Korean System Dynamics Review
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• v.10 no.3
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• pp.5-23
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• 2009

Transportation systems around the world are difficult to maintain sustainability that, in a broad sense, is the capacity to endure. By connecting Entropy theory and systems thinking, we find the current problems and seek alternative plans. Distortions of the current transportation system to improve individual's ease and increasing traffic congestion, impose us the heavy energy consumption and will make increase whole entropy. UNEP reports are presented following three reasons that undermine the sustainabillity. The first one is that the prevalent traffic system highlight benefits of accessibility than benefits of mobility, the second, deteriorate excessive energy consumption, and the last reason is that personal vehicles has inhibited the use of public transportation. Alternative ideas to enhance the sustainable transportation system are these; (1) changeover from 'Ease of movement' to 'space efficiency', (2) evolving the smart traffic system instead of the construction or expansion of the road and (3) creating more comfortable the use of mass transportation. In addition, there are another ways that encouraging modal shift that increase traffic of goods, transport over railway lines and waterways, decongesting transport corridors and elevating technology to improve public transportation. The most importantly, we converse our cognitive process to be willing to enjoy uncomfortable and annoying life.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.110-120
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• 2000

In order to improve the vibration characteristics of mid sized passenger car automatic transmission at idle experimental and theoretical studies have been carried out. Idle shake in "D" range occurs by various reasons such as characteristics of body bending resonance between subsystems and engine mounts etc. Using full vehicle finite element analyses and modal tests we introduce the way to reduce the idle shake in the early design stage. It shows that the exciting forces are the 2nd order torque and force of engine. A powertrain system modes in "D" range are entirely effected by the additional boundary conditions of drive line. As a result the frequencies of subsystems are arranged to be lined up at the idle frequency range in order to avoid the resonances with subsystems To reduce the idle shake mounts of radiator are tuned to act as a dynamic damper to 1st bending frequency of the body. In addition a hydraulic mount which is optimized by Phase Shift Method is applied to the rear engine mount.e rear engine mount.

• Journal of Ship and Ocean Technology
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• v.10 no.3
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• pp.36-48
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• 2006

The train ferry, accommodating trains roll on and off, is often called as 'Railway on the Sea' or 'Blue High-way' since she can connect the railways or roads segregated by the sea and improve the accessibility and continuity of land transport systems. The ferry is especially appropriate to the intermodal transport routes mostly passing through the land but have relatively short sea segment. As the train ferry can considerably reduce the cost and time for cargo handling and modal shift and unnecessitates excessive initial investment on infrastructures such as large harbor cranes or vast container yards, introduction of train Ro-Ro ferries lessen the total transport cost for door-to-door transportation with full exploitation of the existing railway system. All the ports placed in Shandong, Liaoning and Jiangsu provinces of China are connected to the hinterlands via well developed railway and road systems. Therefore, realization of the Incheon-Yantai train ferry system will link Korea railways to TCR and the 4,131-kilometer-long Longhai-Lanxin Railway, along the famous Eurasian Continental Bridge. In the present paper, the Incheon-Yantai train ferry will be introduced as a good example of an efficient multimodal short sea shipping system for Northeast Asia.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.229-240
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• 2008

With the effectuation of Kyoto Protocol, one of the important movement throughout the world is reducing the emission of greenhouse gas which is the main reason of making global warming. The actual factor of greenhouse gas is CO2, and in year of 2002 20% of total CO2 emission was produced only through transportation throughout the South Korea. In the contrary, the recycling of municipal wastes in South Korea was 44.0% in 2002, but it will be targeted upto 53.5% in 2011. All of these show environment-conscious logistics should be implemented together throughout the each stage of distribution with the development of product and service. This study applied survey research for the activities affecting to the emission of CO2 and packaging wastes produced from transportation and packaging stages in logistics area. For this, survey questionary was constructed with five specific areas - strategy, transportation & distribution, custody, packaging, and information. Based on the 148 returned survey questionaries, this study analyzed 52 categories and finally suggests necessary modal shift, collaboration & co-operation in logistics, LCA(life-cycle assessment), and other promoting policies for the environment-conscious logistics in effective way.

• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.685-697
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• 2016

Railroad is considered as an eco-friendly transportation mode because it emits lower greenhouse gases and air pollutants and consumes less energy compared to trucking. To promote rail freight, many countries have implemented various policies, while South Korea has implemented few substantial policies. This study aims to compare and analyze rail freight policies of various countries in order to suggest policy implications to South Korea. We analyze relevant policies of 9 countries; these are classified into 5 categories, and we provide policy implications for facilitating rail freight infrastructure and equipments, grants for the transportation cost using freight rail, and road freight restriction policy.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.209-213
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• 2013

The expense Our country's land logistics system is becoming backlog day by day. The greenhouse gas which it discharges specially from the vehicle causes a ecocide and traffic expense to make. The traffic energy curtailment which the government enforces during that time and environment-friendly green goods policy lost the effect. Therefore, This research propose the car-ferri network which is the most effective logistics system substitutes the land logistics system. This research will contribute improving the north and south logistics network of Pusan and Seoul region and will be able to reduce a various goods expense.

• The monthly packaging world
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• s.240
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• pp.42-61
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• 2013

물류 표준화의 핵심은 수송, 보관, 포장, 상/하역, 정보/보안의 물류활동간의 호환성과 연계성의 확보이다. 국제표준 채택을 의무화하고 있는 WTO/TBT 협정을 차치하더라도 물류표준화의 정도는 국가의 물류경쟁력을 결정짓는 가장 중요한 척도라고 할 수 있다. 특히 한 중 일 3국의 경우 교역랑만 5조 3,236억불로 전 세계 교역량의 17.6%(2010년 기준), GDP 합계 12조3443억 달러로(2010년 기준) 세계전체 GDP 62조 9093억 달러 중 19.6%, 해운물동량은 전 세계 물동량의 60% 이상을 차지하고 있는 상황에서 물류경쟁력은 곧 국가경쟁력으로 보아도 무방하다. 아직도 국내에서는 물류분야 간 연계와 첨단정보기술이 결합된 현장중심의 융 복합 표준이 미비하고 대부분의 경우 해외국가들이 자신들의 입장대로 추진하거나 선점한 표준을 따라가기 바쁜 실정이었다. 스마트물류표준화는 이러한 현실에서 탈피하여 글로벌 물류표준을 선도하고 국내 현실에 적합한 현장물류표준을 반영하자는 취지에서 출발한다. 스마트물류는 i-ULS(Intelligent-Unified Logistics System) 체계, 즉 IT와 각 물류기술을 융합하여 표준화시키는 것은 물론 기존 표준을 산업현실에 맞게 반영해 나가는 것이 국가표준코디네이터로서의 주요한 목표가 되고 있다. 본 고는 전년도 스마트물류 표준화로드업에 작성된 표준화기술 중 산업체 설문을 통하여 10대 주요 표준화 트렌드를 선정하여 정리한 것이다. 10대 표준화 기술로는 순환물류포장시스템, 실시간 위치추적기술, 스마트컨테이너(Smart Freight Containers), 해상용 컨테이너 모니터링 시스템(CTMS), 글로벌 포장 표준모듈, 친환경물류 표준지표, 스마트물류 포장용기, 스마트그린물류센터(Passive Warehouse), 모바일 RFID 물류 적용 기술, Modal Shift(전환교통) 등이 선정되었다. 이번 4월호 특집에서는 10대 표준화 전략트렌드 가운데, 스마트물류에 대해 알아보도록 한다.