• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.21-29
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• 2012

A dual loop waste heat recovery system with Rankine steam cycles for the improvement of fuel efficiency of gasoline vehicles has been investigated. A high temperature loop (HT loop) only recovers the heat of the exhaust gas. A low temperature loop (LT loop) recovers the residual heat from the HT loop, the coolant heat and the remaining exhaust gas heat. The two separate loops are coupled with a heat exchanger. This paper has dealt with a layout of the dual loop system, the review of the working fluids, and the design of the cycle. The design point and the target heat recovery of the HT boiler, a core part of a HT loop, have been presented. The prototype of the HT boiler was evaluated by experiment. For the performance evaluation of the HT boiler, inlet temperature of the HT boiler working fluid was set equal to the temperature degree of sub-cool of $5^{\circ}C$ at the condensing pressure. The exit condition was the degree of super-heat set at $5^{\circ}C$. The characteristics of the HT boiler such as heat recovery and pressure drops of fluids were evaluated with varying flow rates and inlet temperatures of exhaust gas under various evaporating pressure conditions.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.58-66
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• 2011

A 2-loop waste heat recovery system with Rankine steam cycles for the improvement of fuel efficiency of gasoline vehicles has been investigated. A high temperature loop(HT loop) is a system to recover the waste heat from the exhaust gas, a low temperature loop(LT loop) is for heat recovery from the engine coolant cold relatively. This paper has dealt with a layout of a LT loop system, the review of the working fluids, and the design of the cycle. The design point and the target heat recovery of the LT boiler, a core part of a LT loop, has been presented and analytically investigated. Considering the characteristics of the cycle, the basic concept of the LT boiler has been determined as a shell-and tube type counterflow heat exchanger, the performance characteristics for various design parameters were investigated.

• Smart Structures and Systems
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• v.9 no.5
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• pp.393-410
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• 2012

Conventional geotechnical instrumentation techniques available for monitoring of slopes, especially soil-nailed slopes have limitations such as electromagnetic interference, low accuracy, poor longterm reliability and difficulty in mounting a series of strain sensors on a soil nail bar with a small-diameter. This paper presents a slope monitoring system based on fibre Bragg grating (FBG) sensing technology. This monitoring system is designed to perform long-term monitoring of slope movements, strains along soil nails, and other slope reinforcement elements. All these FBG sensors are fabricated and calibrated in laboratory and a trial of this monitoring system has been successfully conducted on a roadside slope in Hong Kong. As part of the slope stability improvement works, soil nails and a toe support soldier-pile wall were constructed. During the slope works, more than 100 FBG sensors were installed on a soil nail, a soldier pile, and an in- place inclinometer. The paper presents the layout and arrangement of the instruments as well as the installation procedures adopted. Monitoring data have been collected since March 2008. This trial has demonstrated the great potential of the optical fibre monitoring system for long-term monitoring of slope performance. The advantages of the slope monitoring system and experience gained in the field implementation are also discussed in the paper.

• Journal of Digital Convergence
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• v.14 no.3
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• pp.381-389
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• 2016

I conducted this study, trying to improve the methods of Sung-Nam city local tax bills, which was based on my previous study where I suggested methods into developing redesign of tax bills. Local tax bills are labeled to be very intricate and puzzling experience to tax payers. To resolve this issue, several local governments have redesigned their tax bills for citizens; however, it was not effective. Therefore I apply the methods to protect their privacy on tax bills and provide checks on their pay bills. Also I design to distinguish between different taxes and change into a better layout for their legibility and better understanding on tax bills. From my previous study, I utilized suggestions into Sung-Nam local tax bills which changed flaws into improvements and easier understanding of the tax payers. I believe the improvements in Sung Nam local tax bills will pursue the public interest of the community through public service design innovations.

• Journal of Power System Engineering
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• v.12 no.1
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• pp.13-19
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• 2008

In this study, a variable induction and exhaust system is applied to turbocharged diesel engine to improve the volumetric efficiency, especially, in a low and transient engine speed range where much of the pollutant matters are expelled out. The volumetric efficiency is known as one of the most important factor which affects significantly engine performance, fuel economy and further emission and noise level. As the torque increase with the engine speed up, the gas flow in an exhaust pipe become pulsating and then has an effect on boost up capacity of air charging into the cylinder and expelling capacity to atmosphere simultaneously. But at a low and idling speed, the pulsation effect was not so significant. Accordingly, resonator was employed to compensate their loss. The variable induction system consists of the secondary pipe, resonator, intercooler, and torque variance were examined with extended operating conditions. In the mean time, for interpretation and well understanding for the phenomena of wave action that arising during intake and exhaust process between turbocharger and variable intake system, the concept of the combined supercharging was introduced. Some of results are depicted which deal with a pressure history during valve events of induction process. Consequently, by the governing of these phase and amplitude of pulsating wave, it enables us to estimate and evaluate for the intake system performance and also, designing stage of the system layout.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.6
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• pp.427-434
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• 2013

In this paper, the design and layout of a 2.5 Gbps arrayed VCSEL driver for optical transceiver having arrayed multi-channel of integrating module is confirmed. In this paper, a 4 channel 2.5 Gbps VCSEL (vertical cavity surface emitting laser) driver array with automatic optical power control is implemented using $0.18{\mu}m$ CMOS process technology that drives a $1550{\mu}m$ high speed VCSEL used in optical transceiver. To enhance the bandwidth of the optical transmitter, active feedback amplifier with negative capacitance compensation is exploited. We report a distinct improvement in bandwidth, voltage gain and operation stability at 2.5Gbps data rate in comparison with existing topology. The 4-CH chip consumes only 140 mW of DC power at a single 1.8V supply under the maximum modulation and bias currents, and occupies the die area of $850{\mu}m{\times}1,690{\mu}m$ excluding bonding pads.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.61
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• pp.327-358
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• 2014

During the past decade after entering the World Trade Organization (WTO), China has quickened its integration into the global economy while its foreign trade has been further invigorated. On the 10th anniversary of China's accession to the WTO, the Chinese government issues White Paper to give a comprehensive introduction to China's foreign trade development. Through this paper, the Chinese government introduces I. Historic Progress in China's Foreign Trade II. Reform of and Improvements to China's Foreign Trade System III. The Development of China's Foreign Trade Contributes to the World Economy IV. Promoting Basically Balanced Growth of Foreign Trade V. Constructing All-round Economic and Trade Partnerships with Mutually Beneficial Cooperation VI. Realizing Sustainable Development of Foreign Trade. At present, the underlying impact of the international financial crisis, the protracted, arduous and complicated nature of the world economic recovery is manifesting itself, and the global economic structure and trade layout face in-depth readjustment. China will make new adjustments to its foreign trade, in an effort to turn foreign trade from scale expansion to quality and profit improvement, and from mainly relying on its low-cost advantage to enhancing its comprehensive competitive edge, thereby turning China from a big trading country to a strong trading power. China's foreign trade is still hampered by many uncertainties and is bound to meet new difficulties and challenges. During the 12th Five-year Plan period China will open itself wider to the outside world as a driver for further reform, development and innovation, make full use of its advantages, strengthen international cooperation in all respects. And at the same time China integrate itself into the world economy on a wider scale and at a higher level. China is willing to work with its trading partners to cope with the various challenges facing the world economy and trade, and promote its foreign trade to realize a more balanced, coordinated and sustainable development, and share prosperity and mutually beneficial results with its trading partners.

• Journal of the Korean Society for information Management
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• v.1 no.1
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• pp.112-126
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• 1984

Since with the information explosion more and more bibliographic materials are continually being produced, the need for improvement of the design of bibliographic materials is urgent for quicker and easier use. One questionaire survey concerned with user preference on 7 Korean bibliographic materials was carried out and got the result that two of those 7 systems, Annual Index to Korean Periodicals, Theses for the Doctor's & Master's Degree in Korea are used most frequently and there are also lots of user discontent about currency, coverage, subject heading, layout and typography. The other study was an experimental searching on 4 Korean bibliographic materials to find out whose coding system is most efficient in information searching. According to the result all of those 4 bibliographic materials are very low in retrieval ratio and Annual Index to Korean Periodicals shows the lowest retrieval ratio. The conclusion suggests that deeper and wider investigation should be carried out as one of national projects for the most useful and efficient presentation of bibliographic materials.

• Journal of the Korea Institute of Building Construction
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• v.16 no.4
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• pp.381-388
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• 2016

The snow control storage facilities have the physical requirements that are an anti-icing and deicing operations. They are efficiently and quickly performed, and composed of a vehicle depot for the snow removal equipment and truck, anti-icing and deicing chemical storages, and the control utilities. This study is to investigate the planning guidance of foreign countries, and the actual conditions of the snow control chemical storage facilities for expressway, the national highway and the local road, and is to suggest the planning guidelines. As some of the authorities have no fixed structures for the snow control storage, this study analyze the 5 cases constructed lately. From the result of the case studies, the operations performed in the snow control storage facilities and drawback of the facilities are analyzed with respect to layout, size, plan, and structure, and the improvement planning guidance is also suggested.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.277-285
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• 2007

The purpose of this study is to analyze seasonal distribution of insects, birds, fishes, and benthos for Gongji stream in Chuncheon and to explore some strategies towards creating a desirable close-to-nature stream. The number of species occurred in the study stream was 23 for butterflies and 149 for other insects, 23 for birds, 15 for fishes, and 47 for benthos. The study stream was dominated by Artogenia rapae, Polygonia caureum, Cyntia cardui for butterflies, and Passer montanus, Anas crecca, Anas platyrhynchos for birds. The dominant species were Rhynchocypris oxycephalus, Zacco plutypus, Carassius auratus for fishes, and Limnodrilus sp. 2, Chiranumus sp. 2, Hydropsyche KUb for benthos. Attracting insect species of higher density requires planting of host plant species and stabilization of plant coverage against disturbances. To enhance species diversify and density of birds, it is desirable to provide diverse habitats including preservation of downstream wetland and natural vegetation, creation of sand bars and islands with sand and gravel, and restriction or traffic passing and parking. Restoring fish and benthos habitats needs improvement of water quality, layout of gravels and stones on sand-dominant streambed, and use of close-to-nature revetment techniques.