• International Journal of Aeronautical and Space Sciences
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• 제16권3호
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• pp.360-369
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• 2015

A methodology for determining the design allowables of composite laminates by using lamina level test data and finite element analysis (FEA) is proposed and verified in this paper. An existing method that yields the laminate design allowables by using the complete test results for laminates was improved to reduce the expensive and time-consuming tests. Input property samples for FEA were generated after considering the statistical distribution characteristics of lamina level test data., and design allowables were derived from several FEA analyses of laminates. To apply and verify the proposed method, Hexcel 8552 IM7 test data were used. For both un-notched and open-hole laminate configurations, it was found that the design allowables obtained from the analysis correctly predicted the laminate test data within the confidence interval. The potential of the present simulation to substitute the laminate tests was demonstrated well.

• 감성과학
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• 제15권2호
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• pp.223-230
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• 2012

This study researched the relationship between the element of "Favorable and Friendly" emotion on product design and the consumer's reaction to it. The emotional elements used here were proposed in the existing study. The research method was divided into 1st test and 2nd test. In the 1st test result, Favorable was related to "want to own, simple, new product and high-class", and also connected with "digital product, gaming product and computers". The products related to Friendly had association with the items about "interesting, cute, familiar, warmth and soft", and also connected with "simple product (toylike, household items, etc), low-price product, product which likes a friend, soft product, kitchen product and beauty treatments product, and so on". In the 2nd test, the preference of emotional product was high than general product, and it was known from the evaluation about design preference and design elements. If the preference was high following the order as: "Formativeness> Trend> Aesthetics> Color", the difference among the scores were small. And then the result about the relationship of emotional design factor "Favorable & Friendly" and evaluation of design preference & design elements was extraction.

• 품질경영학회지
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• 제27권3호
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• pp.79-93
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• 1999

The common accelerated life test(ALT) consists of test methods applying a constant stress, higher than the use condition stress, to items. There we, however, situations for which a progressive stress ALT, in which the stress on a test item is continuously increased with time, Is more convenient to perform testing and simpler in analyzing data than a constant stress ALT. When a product under constant stress s follows a Weibull distribution with parameters $\theta$(5) and $\beta$, maximum likelihood(ML) estimators of parameters involved in the model are obtained and their asymptotic distributions are derived under stress bounded ramp tests in which the stress is increased linearly from use condition stress to the stress upper bound. The optimum test plans are also found which minimize the asymptotic variance of the ML estimator of the log mean life at design constant stress. For selected values of the design parameters, tables useful for finding optimal test plans are given. The effect of the pre-estimates of design parameters is studied.

• 로봇학회논문지
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• 제9권3호
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• pp.160-169
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• 2014

Odometry using wheel encoder is a common relative positioning technique for wheeled mobile robots. The major drawback of odometry is that the kinematic modeling errors are accumulated when the travel distance increases. Therefore, accurate calibration of odometry is required. In several related works, various schemes for odometry calibration are proposed. However, design guidelines of test tracks for odometry calibration were not considered. More accurate odometry calibration results can be achieved by using appropriate test track because the position and orientation errors after the test are affected by the test track. In this paper, we propose the design guidelines of test tracks for odometry calibration schemes using experimental heading errors. Numerical simulations and experiments clearly demonstrate that the proposed design guidelines result in more accurate calibration results.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.479-483
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• 2012

본 논문은 액체산소와 케로신을 추진제로 하는 한국형발사체 1단 엔진의 성능평가를 위한 엔진 지상연소시험설비 개발 현황을 기술하였다. 한국형발사체 75톤급 엔진 지상 연소시험설비의 설계 요구조건에 기반한 설계 규격 및 설비 구성을 제시하였다. 엔진 지상 연소시험설비 기본설계 결과는 향후 한국형발사체 75톤급 엔진 지상 연소시험설비의 상세설계 및 구축을 위한 기본 자료로 활용될 예정이다.

• 한국분무공학회지
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• 제20권3호
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• pp.195-201
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• 2015

This study discusses a fuel injector test bench containing a mechanical type fuel supply system for heavy duty diesel engine. The main focus of this study was to evaluate the design stability of the test bench, which basically measures the injector durability of a multi-hole heavy duty injector by using pure diesel as a test fuel. In this experiment, diesel spray was controlled by a specially designed control box and all the experiments were carried out to measure e.g. fuel injection pressure and fuel injection quantity to understand the injection status which is interlinked with the stability factor of total test bench design. Also, the durability test was performed to understand the heavy duty operation lastingness of the designed system and the flow rate of the installed distributor pump in the fuel supply system of this studying test bench was compared with LO-1 and LO-2 pump. The results of the above mention tests revealed that the injector test bench design and control system can serve the purpose for heavy duty injector.

• 한국군사과학기술학회지
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• 제20권1호
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• pp.55-62
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• 2017

For evaluating a large caliber ammunition tests, indoor ballistic test range is required to reduce the noise and fragments occurring during the test. To ensure the reliability of the indoor ballistics test range design, we carried out the analysis of the indoor test range using the AUTODYNE hydrodynamic code before its construction. The 120 mm tank ammunition is adopted as a reference model and we analysed the characteristics of the pressure distribution at fire area, the structure design at impact area, the over-pressure applied to the tunnel, and the sabot stopper design. The results of the analysis were applied to the design of the indoor ballistic test range.

• 한국군사과학기술학회지
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• 제16권6호
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• pp.779-788
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• 2013

The load requirements should be known to design mechanical structure. This paper proposes a generation method of load requirements using U.S. military specification to design the external mounting structure of the helicopters of which the flight environments such as aerodynamic forces and inertia forces are unknown. In this study, the load requirements which were applied at the design of the pod structure for helicopter captive flight test could be computed by using this method. The validation of proposed method was confirmed from the test flight using developed pod system.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 기초기술학술발표회
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• pp.31-42
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• 2002

The Design criteria are different from one another due to the different engineering properties of rock in the every nation. Most of the test results of the rock-socketed piers were loaded two times of the design load capacities because they would be used in the foundation of the bridge or the building. So we have much difficulties in study of the load capacities of the rock-socketed piers by the test result in Korea. When we design the rock-socket piers, every designer uses the different formula, and makes different results. Recently the demand of the large bridges and the huge buildings has been increased. The adequate design criterion of the rock-socketed pier is urgently needed to design them reasonable. In this paper we analyzed the various design criteria and proposed the adequate design criterion which is based on the test results of the rock-socked piers in Korea.

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.305-314
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• 2003

The ROPS of an agricultural tractor is designed to protect its driver when the tractor overturns. Although the current OECD tests to determine whether the ROPS meets the requirements of the OECD regulation are desirable, they need long time to test. We experimental time and effort by using CAE. We conducted a finite element analysis for the ROPS design of a Dae-Dong tractor cabin in an attempt to reduce the design and manufacturing time. This study shows the interpretative skill using MARC(v.2000) for designing ROPS and difference between the results of testing and FEA. Design process is generally divided into two phases: a concept and a detail design. The concept design uses simple analysis to predict structural behavior, whereas the detail design involves a finite element analysis performed by the results of the concept design. This study focused on the detail design and used Patran(v.2000r2) and MARC(v.2000) of the MSC software corporation. The model consisted of 4812 elements and 4582 nodes. Four tests. specified in the OECD standards, were performed: (1) longitudinal loading test (2) rear crushing test (3) side loading test (4), and front crushing test. Independent analyses were also performed for each test, along with a sequential analysis. When compared, the results of the independent and sequential analyses were found to be similar to the test results.