• Title/Summary/Keyword: Commercial Test

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An Experimental Study on Brake Judder via the Frequency Analysis of the Brake System and Vehicle System of a Commercial Vehicle (상용차량의 브레이크 시스템과 차량 시스템 주파수 분석을 통한 브레이크 저더의 실험적 고찰)

  • Moon, ll-Dong;Kim, Jong-Dae;Oh, Chae-Youn
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.31 no.12
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    • pp.1131-1138
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    • 2007
  • This paper studies experimentally on the building-up process for the amplitude of a commercial truck vibration induced by brake judder. A front axle drum equipped with a drum brake system is utilized for this experiment. A brake dynamo test, a real vehicle ride test and a real vehicle braking test are performed for the analysis of brake judder. The brake dynamo test measures judder by applying brake chamber pressures of 1, 2 and 3 bar at initial brake pad temperatures of $100^{\circ}C$ and $150^{\circ}C$. In order to assess the vertical acceleration at the front axle, the real vehicle ride test on a straight test road with velocities of 20, 40, 60 and 80 km/h is performed. The real vehicle braking test is carried out at the deceleration rate of 0.2g from a velocity of 90km/h for evaluating the vertical, lateral and longitudinal accelerations both at the front axle and at the cab floor under the driver's seat. The magnitudes and frequencies of the measured peak accelerations from the brake dynamo test, the real vehicle ride test and the real vehicle braking test are comparatively analyzed. This paper shows that the vibration produced by brake judder is built up due to the brake system's peak acceleration frequency being close to the vehicle ride mode's frequency.

A Study on the Improving Proposals of the lACS's EMS Test Requirments for the Micro Processor Control Equipments of the Commercial Ship (선박용 프로세서 제어설비의 전자파 내성 시험규격(IACS) 개선안에 관한 연구)

  • 임재열;임준석;민경찬
    • Journal of the Korean Institute of Navigation
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    • v.22 no.4
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    • pp.45-50
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    • 1998
  • A recently constructed commercial ship is a complexive integrated system like a small city in which has a generator, power distributing facilities, various radio equipments and high power circuit breakers are installed. Therfore it could make a malfunction of the microprocessor in the various control units which are so important during the ocean voyage of larger ship. This paper has studied whether is properly required or not on the view of the actual electro magnetic compatibility status on the electromagnetic interference and suceptibility test requirments listed on the IACS (International Association of the Classification Society). Through these results, we are looking forward to the new suggestions of the Electro Magnetic Compatibility test in order to reduce the malfunction in the ship regarding test item, test level, and test condition.

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Quality Analyses and Consumer Acceptability of Gluten-Free Rice Bread and Other Commercially Marketed Bread in Korea (Gluten-Free 쌀빵, 시판 중인 쌀빵 및 밀빵의 품질과 소비자 검사 분석)

  • Kim, Sang Sook;Chung, Hae Young
    • The Korean Journal of Food And Nutrition
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    • v.30 no.2
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    • pp.336-344
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    • 2017
  • The physical characteristics of gluten-free rice bread, commercial rice as well as wheat bread marketed in Korea were delineated, a sensory descriptive analysis performed, and a consumer acceptability study conducted. Both the specific gravity and color of gluten-free rice bread were higher than those of commercial rice and wheat bread. The sensory descriptive analysis revealed that the adhesiveness, fracturability, fermentation odor, and the powdery mouthfeel of gluten-free rice bread were higher than those of commercial rice and wheat bread. In contrast, the sweet odor, sweetness, egg taste, butter taste, and milk taste of gluten-free rice bread were lower than those of commercial rice and wheat bread. The consumer acceptability results revealed differences regarding odor, appearance, taste, texture, and overall acceptance between a blind test and an informed test of gluten-free rice bread, commercial rice, and wheat bread. The consumer acceptability findings were associated with those of the sensory descriptive analysis. In overall, the results indicated that the quality of gluten-free rice bread can be improved by controlling the decrease of adhesiveness, fracturability, and powdery mouthfeel.

A Study on the Profitability of the Commercial Bank in Terms of Interest Rate Marketization : Based on FMOLS Model (FMOLS 모형을 이용한 상업은행 수익성에 대한 연구 : 금리 시장화의 시각에서)

  • He, Yugang
    • The Journal of Industrial Distribution & Business
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    • v.9 no.8
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    • pp.41-50
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    • 2018
  • Purpose - As an important participant in the financial markets, the commercial bank will be impacted by the interest rate marketization. Owing to the special condition of China, this paper tries to explore the impact of operating mechanisms between interest rate marketization and the profitability of the commercial Bank. Research design, data and methodology - This paper applies time series data from 2005 to 2016. Due to the short period of time series, autocorrelation often occurs. Therefore, the fully modified least squares(FMOLS) will be used to conduct an empirical analysis. The reason is that it can move off the autocorrelation between variables and disturbance term. And FMOLS also can make estimated cointegrating parameters closed to normal distribution. More importantly, in order to avoid spurious regressions, the Augmented Dickey-Fuller Test will be used to verify the stationarity of all variables. The total return of asset is treated as the profitability of commercial bank. The net interest spread is treated as a measurement of interest rate marketization. Both are regarded as dependent variables. The non-interest income or gross revenues and impaired loans or gross loans are treated as independent variables. The sixteen representative listed commercial banks are divided into three categories (state-owned, share-holding and city-owned) to conduct an estimation. Results - Via empirical analysis, the findings show that the net interest spread has a positive effect on the profitability of the commercial bank. More specifically, 1% increase in the net interest spread will lead 0.157% increase in the profitability of state-owned commercial bank, 0.269% increase in the profitability of share-holding commercial bank and 0.263% increase in the profitability of city-owned commercial bank. If regarding the sixteen listed commercial city as a whole, 1% increase in the net interest spread will lead 0.267% increase in the profitability of the commercial bank. Conclusions - As the interest rate marketization, the importance of interest rate on the profitability of commercial bank has become more and more significant. The empirical evidences also prove that the net interest spread can bring about the change of the commercial bank's profitability. Therefore, policy-makers of commercial banks should fully understand the operating mechanism between them.

Dynamo Test Research for Performance Verification of CV-NCM Cast Iron Brake Disk (CV-NCM 주철재 제동디스크의 성능 검증을 위한 다이나모 시험연구)

  • Gil, Hyeong-Gyeun;Ko, Tae-Whan;Cho, Dong-Hyun;Han, Seong-Ho
    • Proceedings of the KSR Conference
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    • 2006.11b
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    • pp.274-280
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    • 2006
  • The study is to analyze dynamo test results for various commercial pads in order to verify the performance of brake disk with CV-NCM cast iron. The developed brake disk will apply to 200 km/h tilting trains that is being developed as one part of project for speed-up on Korean existing railroad. The test program is made out suitably for braking condition and performance of test equipment by referring UIC 541-3. Two kinds of resin pad and one kind of foreign sintered pad suitable for 200 km/h trains are used as various commercial pad for the dynamo test. The data aquisition for the maximum and smallest temperature, hot spot, etc. on disk and pad is performed by using the thermocouples and thermal imaging cameras. From this research, we obtained braking characteristics between CV-NCM cast iron disk and pad of various material and will be utilized usefully as basis data of performance optimization of developing sintered pad.

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Ultimate Strength Analysis of Ring-stiffened Cylinders Using Commercial Softwares (상용소프트웨어를 이용한 원환보강 원통의 최종강도 해석(I))

  • 박치모;이승훈
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.271-274
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    • 2000
  • Despite the increasing necessity of accurate estimation of ring-stiffened cylinders' ultimate strength, the complex structural behavior of cylinders has made their design mainly depend on empirical formulas mostly based on insufficient test data rather than theoretical background. This paper has developed the imperfection method which enables the ultimate strength analysis of buckling sensitive structures by combining two general functions of common commercial finite element softwares, linear elastic buckling analysis and nonlinear stress analysis. Developed method was applied to two of the world most renowned commercial softwares, MSC/NASTRAN and ABAQUS, for the analysis of ring-stiffened cylinders and unexpectedly big difference in their analysis results was found. This tells that many widely used commercial softwares has their different strong points and week points and the choice of commercial software should be cautiously made after thorough inspection. This paper ends with some useful information about which of the aforementioned two softwares is more appropriate respectively for linear elastic buckling analysis and ultimate strength analysis of ring-stiffened cylinders.

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The Removal of Surfactants and Commercial Detergents by Oenanthe javanica (미나리를 이용한 계면활성성분 및 합성세제 제거에 관한 연구)

  • 김경민;최한영;신정식;나규환;이장훈
    • Journal of Environmental Health Sciences
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    • v.23 no.4
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    • pp.115-120
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    • 1997
  • The purpose of thesis was to investigate the removal efficiency of surfactants and commercial detergents by Oenanthe javanica that is one of aquatic plants in Korea. The experiment is concerned with measuring the concentrations of surfactants and commercial detergents in different media: 1) in pure water, 2) in water containing Oenanthe javanica, 3) in water containing Oenanthe javanica and commercial nutrients. The surfactants used in this research include linear alkylbenzene sulfonates (LAS), $\alpha$-sulfo fatty acid methyl esters(MES), and alkylbenzene sulfonates(ABS). Two commercial detergents designated as A and B were in the forms of power and liquid. The results showed that LAS and MES were more effectively removed by Oenanthe javanica probably because these have a chain of linear carbon than on ABS with a branched carbon structure. In the case of commercial detergents, when the except was performed on the basis of surfactants proportion, the removal trends were similar to LAS and MES. The 5-day cultivating test with initial concentration of 0.5-1.0 ppm surfactants showed that less than 10% was removed if no nutrients an Oenanthe javanica were added. When Oenanthe javanica was added into the sample solution containing surfactants, the removal efficiency was increased 100% for the solution containing 0.5-1.0 ppm 60-70% for 5-10 ppm. In addition, chlorisis on Oenanthe javanica was observed due to surfactants and commercial detergents for all three cases. To test the dependence of population density on nutrients, the initial population density was made 300 g/0.4 m$^2$. Throughout the 5-day experiment, the on Oenanthe javanica grew 20-25% with 0.5-1.0 ppm without the synthetic nutrients but by 5% with a high concentrations of 5-10 ppm. The population density was appeared to be independent of synthetic nutrients. The leaves were to be grown with synthetic nutrients, while roots were grown without synthetic nutrients. Based on this research, the fundamental data concerning cultivation and an adequate adjustment of the water condition can provide for the utilization of Oenanthe javanica in real water treatment system.

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An Effectiveness Analysis of Commercial Vehicle's Loading Pattern and Prevention of Overloading with On-board Truck Weight Sensors (화물차량 부착 중량센서 적용을 통한 운행패턴 및 과적 예방 효과 분석)

  • Kim, Jong Woo;Jho, Youn Beom;Jung, Young Woo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.17 no.6
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    • pp.153-172
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    • 2018
  • Overloading of Commercial vehicles have been an important area of transportation as one of the main causes of pavement damage, bridge collapse, severe traffic accident, etc. In this study, we analyzed the effects of overweight prevention by analyzing overweight driving patterns and using weight sensors. First, we analyzed relevant literatures of overweight and surveyed the commercial weight sensors. Then we chose the typical type of overweight vehicles based of overweight enforcement data analysis. MEMs inclinometer weight sensor were installed to 10 test vehicles and data was collected by weight sensors and gps in real time. As a result of gross vehicle weight and axle weight analysis, it was found weight sensor could decrease overweight rate. However, since the number of samples of test vehicles is insufficient to represent the whole commercial vehicle, further studies are deemed possible through the extension test.

Information Content of Commercial Paper Credit Rating Changes In Korea (우리나라 기업어음등급평가의 정보효과 검증)

  • 박범호;최호석
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2000.10a
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    • pp.89-92
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    • 2000
  • The purpose of this thesis is to investigate the information content of commercial paper credit rating changes of Korean firms. The result shows neither sinificant daily abnormal returns nor significant cumulative daily abnormal returns over the test window. This ind icates that commercial paper rating changes are not informative to investors. A sensitivity analysis conducted for the portfolio of subsample shows a similar result. This thesis, however, may contribute to the better operation of Korean financial market by providing several directions to establish credit-based financial transactions.

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Investigation of Elemental Mercury Oxidation on Commercial SCR Catalysts in Flue Gas of Fossil Fired Power Plant (상용 SCR 촉매상에서 화력발전소 배기가스 중 원소수은의 산화반응연구)

  • Lee, Seung-Min;Lee, Jung-Bin
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.3
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    • pp.245-252
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    • 2010
  • For the purpose of evaluating to remove elemental mercury using SCR (Selective Catalytic Reduction) catalysts, the result of the concentration variation of elemental mercury in lab experiment and field measurement was compared. The effect of the elemental mercury oxidation on commercial catalysts was studied in simulated gas. Three species of SCR catalyst, $V_2O_5-TiO_2$ type, were selected. The elemental mercury reduced 30% without HCl gas in SCR operating condition. But the width of reduction increased 60% at 20 ppm HCl gas. According to the result of field measurement, reduction rate of elemental mercury at SCR outlet showed 60%. The total mercury concentration decreased about 20%. The results were similar to the lab test. The results of chemical analysis of test sample showed increase of mercury concentration but surface change was not observed.