• 한국자동차공학회논문집
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• 제22권7호
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• pp.63-69
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• 2014

Domestic automobile companies have adopted drum type brake system for commercial vehicles. However recently those companies have been applying disc-brake system to solve vehicle control-instability and inefficient heat discharge performance of conventional drum brake system for a medium commercial vehicle. Because the kinetic energy of a running commercial vehicle is relatively high, the brake system should discharge lots of heat energy while braking. A ventilated type brake disc has been used to increase heat discharge performance of a brake system. The vent structure of a disc highly affects cooling efficiency. This paper compares thermal characteristics of three types of vent structure in JASO C421 braking condition. It is found that the slant bend type disc has the lowest temperature and thermal stress distributions in the braking condition.

• 드라이브 ㆍ 컨트롤
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• 제17권4호
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• pp.152-159
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• 2020

This study reviews the rear or tag axle steering system's concepts and technology applied to commercial vehicles. Most commercial vehicles are large in size with more than two axles. Maneuvering them around tight corners, narrow roads, and spaces is a difficult job if only the front axle is steerable. Furthermore, wear and tear in tires will increase as turn angle and number of axles are increased. This problem can be solved using rear axle steering technology that is being used in commercial vehicles nowadays. Rear axle steering system technology uses a cylinder mounted on one of rear axles called a steering cylinder. Cylinder control is the primary objective of the real axle steering system. There are two types of such steering mechanisms. One uses master and slave cylinder concept while the other concept is relatively new. It goes by the name of smart axle, self-steered axle, or smart steering axle driven independently from the front wheel steering. All these different types of steering mechanisms are discussed in this study with detailed description, advantages, disadvantages, and safety considerations.

• 한국빅데이터학회지
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• 제5권2호
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• pp.171-186
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• 2020

우리나라의 영세 소상공인과 자영업자의 비중이 주요 선진국에 비해 과도하게 높고 빈번한 창업과 폐업이 반복되어 국가 경제에 막대한 피해를 초래하고 있다. 이러한 문제를 해결하기 위해 소상공인을 위한 다양한 연구가 진행 중이며, 정부는 소상공인을 위해 빅 데이터를 이용한 상권정보 분석 서비스를 제공하고 있다. 상권정보 분석 서비스 중 서울시에서 운영하는 우리마을가게 상권분석서비스는 소상공인 관련 빅 데이터 분석 서비스를 제공하기 위해 지속적인 서비스 개선을 진행하고 있다. 그러나 다양한 기관에서 제공받은 빅 데이터를 통합하여 서비스를 구축하였기 때문에 데이터 신뢰성의 한계, 데이터 분석의 한계, 서비스 구성의 한계가 존재한다. 이러한 한계를 극복하기 위해 본 논문에서는 빅 데이터 기반의 상권 서비스와 연계 분석이 가능한 위치기반 설문조사시스템을 제안한다. 제안된 설문조사시스템은 설문정보와 상권정보를 연계하여 빅 데이터 상권 분석 서비스를 확장할 수 기반을 마련하였다.

• 항공우주시스템공학회지
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• 제5권1호
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• pp.24-29
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• 2011

The industry related to commercial space transport is growing rapidly as a futurity industry all over the world and America is leading them. If this trend continues, domestic individuals or private enterprises may plan for the commercial space transport business by adopting the advanced technology. Therefore it is necessary to make a law to control the business in our country for the industrial development and the growth related to commercial space transport. This paper provides outline for domestic commercial space transport law by the study and analysis of U.S. commercial space transport laws.

• 산업공학
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• 제7권1호
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• pp.67-74
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• 1994

In this study, we propose an integrated CAD(Computer Aided Design) library database in a heterogeneous commercial ECAD(Electronic CAD) environment. To effectively solve engineering problems focused on BOM data extraction we use a software system called schematic capture and company-wide standard electronic part information loaded on different commercial ECADs. We unify many commercial ECADs into one schematic capture and a variety of PCB(Printed Circuit Board) design tools. For this purpose we develope a model for linking CAD symbol library with company-wide standard part information. We also develope a schematic design data conversion scheme and show how to extract PBA level BOM data using our customized schematic capture. This system is being operated in an X-Window based engineering work station and commercial RDBMS base.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.166.1-166
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• 2001

Anti-lock Braking System(ABS) is a device which prevents the wheels form locked up under emergency braking of a vehicle. So it helps the vehicle to maintain the steerability and shortens the braking distance by maintaining optimal frictional force during braking since the tire road slip is controlled in acceptable range. Recently, ABS is accepted as a standard equipment in vehicles, especially in commercial vehicles(bus and trucks). Commercial vehicles don´t use hydraulic lines but use pneumatic lines for braking system mostly. In this paper, ECU(Electronic Control Unit) for the anti-lock braking system of a commercial vehicle which is equipped with a full-air brake system and its control algorithms are presented. In this algorithm wheel speed acceleration flags and wheel slip flags are defined ...

• 한국기계가공학회지
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• 제11권2호
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• pp.40-46
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• 2012

In this study, numerical analysis was conducted to understand the flow characteristics of lubrication system in a manual transmission installed in a commercial vehicle. Also, the analysis was conducted with the purpose of improving the heat and lubricative condition of the transmission. Discharging flow rates on each oil hole outlet according to various engine rotating speed and the length of oil hole branch was calculated. In conclusion, as engine rotating speed is high and the length of oil hole branch is long, the discharging flow rate is high by virtue of the centrifugal force. In addition, this study proposed data for optimal design of lubrication system in manual transmission for a commercial vehicle.

• International Journal of Computer Science & Network Security
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• 제22권4호
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• pp.175-182
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• 2022

The new commercial maritime law in the Kingdom came comprehensive and detailed for all topics related to commercial maritime navigation, thus responding to most of the problems that arise in the field, specifically regarding the ship as the focus of the rules of maritime law. This system defines the ship in law, regulates its civil status, determines how to name it, determine its domicile, and the conditions for acquiring Saudi nationality. It also contained a regulation of the rights granted to ships by ownership, as well as their lease and mortgage, the mechanism of attachment to them to settle debts and the rights in kind dependent on them and controlling the rights of third parties on ships and the procedures for forcibly selling them from precautionary seizure and executive seizure and then forced sale in public auction. Until this research was an effort to present a clear picture about the legal system of the ship in the new Saudi commercial maritime system and confirming the extent of the success of the Saudi legislator with the ship system in highlighting the legal frameworks for this facility prepared for maritime navigation.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권2호
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• pp.144-149
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• 2006

This paper describes a novel automated analysis system for bellows of piping system. An automatic finite element (FE) mesh generation technique, which is based on the fuzzy theory and computational geometry technique, is incorporated into the system, together with one of commercial FE analysis codes and one of commercial solid modelers. In this system, a geometric model, i.e. an analysis model, is first defined using a commercial solid modelers for 3-D shell structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay triangulation technique is introduced as a basic tool for element generation. The triangular elements are converted to quadrilateral elements. Practical performances of the present system are demonstrated through several analysis for bellows of piping system.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권1호
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• pp.58-63
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• 2006

This paper describes a novel automated analysis system for bellows of piping system. An automatic finite element (FE) mesh generation technique, which is based on the fuzzy theory and computational geometry technique, is incorporated into the system, together with one of commercial FE analysis codes and one of commercial solid modelers. In this system, a geometric model, i.e. an analysis model, is first defined using a commercial solid modelers for 3-D shell structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay triangulation technique is introduced as a basic tool for element generation. The triangular elements are converted to quadrilateral elements. Practical performances of the present system are demonstrated through several analysis for bellows of piping system.