• Journal of environmental and Sanitary engineering
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• v.21 no.3 s.61
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• pp.15-26
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• 2006

As traffic in city-centre around the world continues to increase, so levels of atmospheric pollutants continue to rise. High concentrations of NOx can have negative effects on human health, and we must find new ways to reduce their levels in the air we breathe. Nitrogen oxide gas (NOx), consisting of nitrogen monoxide (NO) and nitrogen dioxide $(NO_2)$ produced using $O_3$ oxidation, at a low concentration corresponding to that on roads as a result of exhaust from automobiles, was carried out to evaluate the removal characteristics of NOx through a laboratory-scale biofilter packed with soil as a packing material. A mixture media (yellow soil (30%): soil (40%): compost (10%): a used briquet (20%)) was applied. After about 1day of operation, the removal efficiency for $NO_2$ in all experiments with a constant condition ($25^{\circ}C$ and water humidity (60%)) was over 98%. The retention times of the section between phase I and phase II for formation and reduction of $NO_3$ NO and $NO_2$ on the initial $NO_3$ concentration was 50min $(O_3:195\;ppb),\;55min\;(O_3:925\;ppb),\;65min\;(O_3:1743\;ppb),\;70min\;(O_3:2616\;ppb),\;75min\;(O_3:3500\;ppb)$, respectively The soil biofilter system is a unique technology that purifies urban air by utilizing the natural processes that take place in the soil. Although some of the processes are quite complex, they can broadly be summarized as adsorption onto soil particles, dissolution into soil pore water, and biochemical.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.7-17
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• 2014

Power electronics modules are semiconductor components that are widely used in airplanes, trains, automobiles, and energy generation and conversion facilities. In particular, insulated gate bipolar transistors(IGBT) have been widely utilized in high power and fast switching applications for power management including power supplies, uninterruptible power systems, and AC/DC converters. In these days, IGBT are the predominant power semiconductors for high current applications in electrical and hybrid vehicles application. In these application environments, the physical conditions are often severe with strong electric currents, high voltage, high temperature, high humidity, and vibrations. Therefore, IGBT module packages involves a number of challenges for the design engineer in terms of reliability. Thermal and thermal-mechanical management are critical for power electronics modules. The failure mechanisms that limit the number of power cycles are caused by the coefficient of thermal expansion mismatch between the materials used in the IGBT modules. All interfaces in the module could be locations for potential failures. Therefore, a proper thermal design where the temperature does not exceed an allowable limit of the devices has been a key factor in developing IGBT modules. In this paper, we discussed the effects of various package materials on heat dissipation and thermal management, as well as recent technology of the new package materials.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.257-263
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• 2018

The purpose of this study is to develop an automatic inspection system for a part of the differential drive gear into the transmission. This technology will make using the microvision automatic test equipment and automatic test equipment microlaser. This is that the operator intends to make the defect rate 0 in the inspection stage of the product which has been carelessly processed. The equipment developed in this research project will be applied to many areas. Packaging companies, nut bolt processing company, precisely supplier for printing on top of the semiconductor, SMT, etc. The company wants to sell the vision inspection equipment for various applications. If the defective rate of 0 is achieved through this research project, it is also possible to secure a stable supply from the parent company, and to lay the foundations for exporting based on product reliability. When the automatic inspection system is applied to domestic automobile parts processing companies, the reliability of automobiles in Korea will be greatly increased.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.11
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• pp.1029-1035
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• 2013

This paper proposes a real time lane detection algorithm using LRF (Laser Range Finder) for autonomous navigation of a mobile robot. There are many technologies for safety of the vehicles such as airbags, ABS, EPS etc. The real time lane detection is a fundamental requirement for an automobile system that utilizes outside information of automobiles. Representative methods of lane recognition are vision-based and LRF-based systems. By the vision-based system, recognition of environment for three dimensional space becomes excellent only in good conditions for capturing images. However there are so many unexpected barriers such as bad illumination, occlusions, and vibrations that the vision cannot be used for satisfying the fundamental requirement. In this paper, we introduce a three dimensional lane detection algorithm using LRF, which is very robust against the illumination. For the three dimensional lane detections, the laser reflection difference between the asphalt and lane according to the color and distance has been utilized with the extraction of feature points. Also a stable tracking algorithm is introduced empirically in this research. The performance of the proposed algorithm of lane detection and tracking has been verified through the real experiments.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.6
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• pp.33-37
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• 1980

The information display control system is designed and implemented on an automobile in which the conventional panel displays are replaced by electronic ones. The system hardware consists of three main parts, i. e., (i) the function select keyboard (ii) the central processing unit (iii) the displays, The system software consists of main routine and several interrupt service routine such as keyboaiuand display interrupt service routine:. The main routine handles various sensor inputs to generate the appropriate information for the driver such as running speed, available fuel quantity. coolant temperature, battery voltage, remaining distance to the destination , time of day, and so on. Finally the results of the field test of the system and some associated difficulties of realization problems are discussed.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.125-134
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• 2011

Art Deco is a decorative and eclectic design style, popularized at the interwar period. The term Art Deco derives from the Exposition Internationale des Arts D$\acute{e}$coratils et Industriels Modernes held in Paris in 1925. The aim of the exposition was to create new modern aesthetics. This exposition introduced the modern decorative and industrial art to the world and influenced all designers of area, including architects, interior designers, industrial designers, craftsmen, fashion designers, etc. Art Deco designers applied inspirations from a variety of sources and movements such as the Cubist abstract, the Neoclassical refinement, Egyptian exotic elements, Babylonian and Aztec temples, the machine aesthetic, avant-garde movements, etc to their modern works. Art Deco style rapidly spread all over the design areas nationwide in America. In Art Deco architecture, in particular, its inception was French but its domination was American. Skyscrapers, airplanes, automobiles, ocean liners, jazz, Hollywood film, streamline, and native Indian symbols are the defining features of American Art Deco. This study began from questions on how these features are expressed and stylized to decoration elements as the modern aesthetics in American Art Deco architecture. Thus, the purpose of the study is to find out the ornamental and eclectic factors of Art Deco style and to define a concept of the modernity and the regionalism of Art Deco architecture in America. This article provides an overview of the decoration style of Art Deco architecture in America through the analysis of ornamental and eclectic factors reflecting diverse roots. It also analyzes the wide variety of building examples of American Art Deco which represent regionalism. In addition, this study focuses on Art Deco architecture in Miami, Florida. Miami is one of typical cities that has the most unique regional aspects of 1920's to 1940's in Art Deco architecture. Miami Art Deco architecture reveals the tropical and nautical references such as streamlined and curved walls, exotic animal motifs, flora and fauna motifs, and marine motifs: use of glass block, porthole window, terra-cotta, and pastel color stucco.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.849-854
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• 2013

Many researches on green ship with increasing on economics, efficiency and convenience have been carried out consistently. One of them is development of diesel engines with electronic control. While small duty one for automobiles had been adopted mainly already, disseminating heavy duty one for ships has trouble due to safety and reliability. In order to solve these problem in this study, performance of electronic control and cam type engine installed in parallel on training ship HANBADA of korea maritime university was analyzed and compared. It is certain that specific fuel oil consumption of the electronic control type is lower than cam type and excellent at lower engine load, especially. And the electronic control type shows more effective characteristic at sea trial on specific fuel oil consumption.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.6
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• pp.465-473
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• 2008

Type II compressed natural gas(CNG) storage vessels for automobiles have been acknowledged for their excellence and have recently become established in local regions. Their supply is not only to automakers in Korea such as Hyundai Motors but they are being increasingly exported. Although the available products have undergone safety evaluations and are certified by an authorized institution they are still short of the optimal design that is possible for such storage vessels. This research investigates the shape and thickness of the dome with the aim of optimizing the type II CNG storage vessels by using a finite element analysis technique. CNG storage vessels can be largely divided into 3 parts namely, the hear part, the cylinder part and the dome part. The head part is designed by means of a hot spinning process and this method is safer than that used in the design of the dome part even though its shape is similar. The thickness of the liners and reinforcing materials was optimized based on the requirements of the cylinder and dome parts. In addition, the shape of the dome, which is most suitable for Type II CNG storage vessels, is proposed by a process of review and analysis of various existing shape, and then conducting a structural stability evaluation to ensure the optimal design plan.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.10
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• pp.975-981
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• 2017

Savings in weight using lightweight materials such as aluminum alloy can lead to increase fuel economy. However, compared to steel, aluminum alloys have a lower strength for an equivalent life cycle. To reduce the weight of automobiles, research is being performed on the fabrication of lighter and stronger torque struts without having to sacrifice the safety of automotive components. In this study, a weight reduction design process for torque struts is proposed that is based on varying von-Mises stress contours using an aluminum alloy (A356) having a tensile strength of 245 MPa, instead of STKM11A steels. The optimized design can reduce the weight of the original steel torque strut by over 42% and it can contribute to the design of light-weight components and to the safe design of torque struts.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.10
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• pp.915-921
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• 2017

Recently, studies to reduce vibration and noise of automobiles have been actively conducted. However, previous studies did not concentrate on the optimization of the mount system with passive or active mounts. This study analytically studies an active mounting system with three active structural paths between source and receiver and the feasibility has been verified. Active mounting system has a coupled structure of piezoelectric stack actuators and passive mounts. A dynamic model of the whole system is prepared and the control force and phase of the stack actuators in each path are determined to target full isolation of each path. Its performance on vibration attenuation is investigated and based on it, optimized combinations of passive and active paths for the best attenuation are presented.