• 동력기계공학회지
• /
• 제9권4호
• /
• pp.148-154
• /
• 2005

Thermostable property is one of most important characteristics of graphite. Commercial graphites sheet from expanded graphite is using for high-temperature elements. Nowadays the new plant with high performance is developed in field of chemical industries, so the need of graphites is increasing rapidly. In this paper, the thermostable properties of newly developed graphite products with high density is investigated. I introduced the graphite material which developed for these heat tests by NGF method in order to test thermostable properties by comparing to the results of the commercial graphite sheet from expanded graphite in same condition. Through measuring the weight reducing ratio with various specimens in some conditions, I investigated the thermostable characteristics of these materials. It is verified that the graphite products by NGF method has almost same or superior thermostable properties comparing with that of commercial graphite sheet. Also the graphite products by NGF method have possibility of being better in thermostable properties.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2014년도 추계학술대회 논문집
• /
• pp.472-475
• /
• 2014

Abnormal cab vibrations in the Y direction in commercial vehicles during driving(70~90kph) are not common vibrations that happen to vehicles during driving and can be an obstacle to normal driving. This study conducted Operation Deflection Shape(ODS) testing to identify the causes of those abnormal cab vibrations and find solutions for them and also a sine sweep test to find resonance and frequency in the cab suspension system and set directions for improvement. The study also altered the shape of the bush inner part for changes to the rigidity features of the cab bush in the Y direction and revised the design with optimal rigidity in the Y direction, thus improving abnormal cab vibrations in the Y direction during driving.

• ETRI Journal
• /
• 제19권3호
• /
• pp.83-97
• /
• 1997

The CDMA Mobile System (CMS) has been developed by Electronics and Telecommunications Research Institute (ETRI) and field-tested for commercial service deployment in Korea. The project was started in 1989 and completed in 1995 with the CMS commercial test. During the course of development, there had been active technical cooperation with Qualcomm, Inc. and Korean manufacturers. The CMS adopted the basic CDMA concepts conforming to Korean CDMA system which was derived form IS-95. The CMS functions are allocated to subsystems by considering efficiency and expandability. The CMS consists of mobile stations and the infrastructure which is composed of base stations, mobile exchanges and home location register/authentication center. The commercial field tests performed both in Taejon and Seoul have indicated that the CMS capacity is 10 to 15 times larger than that of AMPS. This paper overviews the development history, system characteristics, architecture and test results.

• 한국식생활문화학회지
• /
• 제21권5호
• /
• pp.456-462
• /
• 2006

The object of this research is to assess both the preference and the recognition on commercial cream soup by gender and age group to design reliable proposals for better product. Of 461 questionnaires handed out to residents at Daegu, Busan and Gyeongju in youngnam area. The data were analysed by chi-square test, t-test and one way ANOVA. The results are summarized as following: (1) the response rate of 78.6 percent liked soup because of it's taste, (2) respondents in ages 20${\sim}$30's showed higher preference than respondents in ages 40${\sim}$50's (3) main ingredient is the most important consideration as purchase, (4) vegetable cream soup and mushroom cream soup are shown as highest ranking on the recognition of soup, (5) mushroom cream soup and corn cream soup are shown as highest ranking on the preference of soup.

• Korean Chemical Engineering Research
• /
• 제51권5호
• /
• pp.615-621
• /
• 2013

본 연구에서는 수계 레독스 흐름전지에서 사용하는 멤브레인 특성분석방법을 개선하여 비수계 레독스 흐름 전지를 위한 멤브레인 특성분석방법을 확립하였다. 비수계 레독스 흐름 전지에 적합한 멤브레인 특성을 확인하기 위해 상용 멤브레인의 이온교환능력, 이동수, 이온 전도도, 활물질 투과도, 전지효율 실험 등 특성분석들을 수행하였다. 상용 음이온 교환 멤브레인의 특성분석 실험을 통해 충 방전 효율 및 에너지효율과 이온 선택성의 상관관계를 조사하였다. Neosepta AHA 음이온 교환 멤브레인은 이동수 측정에서 0.81의 값으로 비수계 전해질에서 비교적 낮은 이온 선택성을 보였지만, 충방전 전지효율 평가에서는 92%의 충 방전효율과 86%의 에너지효율을 각각 나타내었다. 또한 이온의 선택성이 없는 다공성 멤브레인은 높은 전류밀도의 비수계 레독스 흐름 전지에 적절함을 알 수 있었다.

• 한국기계가공학회지
• /
• 제17권2호
• /
• pp.130-136
• /
• 2018

This study develops a seat with electric motor technology for a one-ton grade commercial vehicle. While applying electric motor technology, the FMVSS 210 seat frame strength test is also conducted to examine the product's weak parts. The seat frame strength test used the FMVSS 210 test standard and the ANSYS program was used to simulate the test and identify weak parts in the deformation and strain values. The test results showed that the cushion frame and slide rail connection bracket were fractured at loads of about 10,000 N. Similarly, the maximum stress and strain values in the bracket were obtained in the simulation results. On this basis, it was evaluated that the connection part bracket was a considerably weak part in the case of the first model, and changing the shape of the bracket and reinforcing the strength were required. In addition, the seat belt anchorage test results and simulation results were compared to assure their validity. In the comparison results, the error for each is about 5-10%. Therefore, the simulation performed in this study is considered to have produced reasonably accurate results.

• 설비공학논문집
• /
• 제25권8호
• /
• pp.438-442
• /
• 2013

The alternative refrigerant R436B is applied, to assess the application feasibility for a commercial cooling water system. The characteristic stability was verified by Sealed glass tube test and Autoclave test. R436B is chemically stable with the compressor material. The Oil miscibility test shows the usual compressor oil mixed well with R436B. Through the life acceleration test, the cooling performance is maintained. Though slight changes in oil and capillary tube diameter were found, they were within the permitted range. R436B should be applied to commercial cooling water systems as a simple replacement for the usual refrigerant.

• 한국자동차공학회논문집
• /
• 제22권5호
• /
• pp.35-43
• /
• 2014

The automobile industry requires technological innovations to reduce fuel consumption with the public interest in environmental conservation in recent years. Thus, the hybrid system is applied not only to passenger cars but also commercial vehicles. The purpose of this paper is to develop engine ECU_ILS to develop commercial hybrid vehicles. In order to develop the engine and vehicle, the dynamometer and exhaust gas analyzer is needed. However, a lot of time and cost are required. In contrast, the model-based development environment that can be applied to a variety of test conditions can reduce development time. Therefore, a HILS system environment that can consider the behavior of actual vehicles for evaluation of the control logic, fuel consumption and exhaust gas is required. This engine ECU_ILS system was developed in this study, can analyze parameter such as the fuel injection rate, fuel injection time, fuel consumption and exhaust gas like the actual vehicle test using map data. Also, this system is expected to be able to analyze the characteristic of vehicle behavior and the development of peripheral device in relation to engine and vehicles. This HILS system can be used to develop control strategies of commercial hybrid vehicle systems in the future.

• 한국항해학회지
• /
• 제20권3호
• /
• pp.137-162
• /
• 1996

Today diving activity and technology are indispensable for underwater technology and offshore engineering. And then diving business is still more important to business of subsea. This study surveyed the issue of diving activity in Korea as for compared foreign diving activity. This paper analyzed the status of diving business that include commercial and sport-leisure diving business and development of commercial divers in Korea. This paper reputed the object, the necessity and the character of commercial divers. For the purpose of this study is considered in order to analyze the environment of commercial divers and propose the planning for industrial diving business. Under the present circumstance in Korea this development planning study may be restricted. but the effective planning to activate Korean commercial diving business is abstracted as follows; First, establishment of new course, grade, certificate and licence test for diver is a pre-requisite factor for the successful enactment. Second, the political assistance of concerned government authority is needed. Third, establishment of Korean diving school and medical center for divers are strongly required. Forth, setting up the department of diving activity in university.

• 한국자동차공학회논문집
• /
• 제16권5호
• /
• pp.44-48
• /
• 2008

This paper describes on studies of the heavy duty engine calibration for better fuel economy based on real driving conditions. Using testbed validated software simulation of the engine and turbocharger system, an alternative turbocharger specification, with potential to improve fuel economy was identified. Secondly, the engine calibration was modified to optimize vehicle fuel economy over a typical customer drive cycle whilst still meeting the steady-state (testbed) emissions legislation. These results were confirmed by field testing of a vehicle equipped with the updated specifications. This study found good agreements between the prediction and the field test on the vehicle fuel economy improvements of the express bus with updated calibration and turbocharger.