• Title/Summary/Keyword: Test procedures

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A Study on Implementation of an Underwater Vehicle HILS/MILS System in Synthetic Environment (합성환경 하에서의 수중운동체 HILS/MILS 구현 기법 연구)

  • 남경원
    • Journal of the Korea Institute of Military Science and Technology
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    • v.5 no.2
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    • pp.132-148
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    • 2002
  • In this paper, development procedures of an Underwater Vehicle HILS/MILS System in SE(Synthetic Environment) are described. As this System is developed, we can obtain the more powerful tool which can be used to test and verify operational logics and algorithms of an Underwater Vehicle as well as its hardware in various tactical situations.

An Experimental Study on Hydraulic Characteristics in Seaclike Closure Gap (방조제 체절구간에서의 수리특성에 관한 실험적 연구)

  • 나정우;권순국
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.28 no.4
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    • pp.57-65
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    • 1986
  • A new method of determining the discharge coefficients and velocity which are very important factor to calculate the weight of riprap materials in the seadike closure gap can be derived through the hydraulic model test. On the basis of the results of this study, general hydraulic aspects between gradual horizontal and vertical closure method are compared, and also discharge and velocity computation procedures are presented.

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Tests For and Against a Positive Dependence Restriction in Two-Way Ordered Contingency Tables

  • Oh, Myongsik
    • Journal of the Korean Statistical Society
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    • v.27 no.2
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    • pp.205-220
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    • 1998
  • Dependence concepts for ordered two-way contingency tables have been of considerable interest. We consider a dependence concept which is less restrictive than likelihood ratio dependence and more restrictive than regression dependence. Maximum likelihood estimation of cell probability under this dependence restriction is studied. The likelihood ratio statistics for and against this dependence are proposed and their large sample distributions are derived. A real data is analyzed to illustrate the estimation and testing procedures.

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Exact Activity Overlapping Method for Time-cost Tradeoff

  • Gwak, Han-Seong;Lee, Dong-Eun
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.109-110
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    • 2015
  • This paper presents a computational method that identifies an exact set of optimal overlap rates between critical activities to meet job site specific needs by using rework cost-slope. The procedures to compute the exact solution are provided in peudocode algorithm. The method is coded into Exact Concurrent Construction Scheduling system that allows practitioners to make more informed decision in accordance with the site-specific condition involved in the overlapping of critical activities. Test cases verify the validity of the computational method and the usability of the system.

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Proposal of Concrete Pull Off Bond Strength Measurement Method for Bridge Deck Overlay (교면 덧씌우기 콘크리트의 인발부착강도(引拔附着强度) 시험법(試驗法) 제안(提案))

  • Kim, Seong-Hwan;Kim, Dong-Ho;Kim, Hyun-Oh;Lee, Bong-Hak
    • Journal of Industrial Technology
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    • v.23 no.A
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    • pp.149-156
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    • 2003
  • The development and maintenance of a sound bond are essential requirements of concrete repair and replacement. The bond property of a overlay to its substrate concrete during the lifetime is one of the most important performance requirements which should be quantified. A standard or a verified bond strength measurement method is required at field for screening, selecting materials and quality control for overlay or repair materials, but no test method has been adopted as a standard. In this study, a concrete pull off bond strength measurement method for field application is proposed and evaluated. This study compares the splitting tensile test, slant shear test, nipple pipe direct tensile test, flexural adhesion test, briquette tensile test, jumbo nail pull-out test and core pull-off test with their test procedures. From these comparison and investigation, core pull-off test is selected as a main topic of this study because of it's suitability for in situ testing, simplicities in field application and clearness at interface boundary condition. Thus, the proposed core pull off test is evaluated to be the most appropriate method for field application in a simple manner. The fracture surface and fracture mode could be easily determined by visual observation of failure surface of the field specimen. The core pull off test was found to be sensitive to surface condition and latex contents at latex modified concrete.

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Failure Analysis of Aircraft Software Test Cases from a Perspective of Requirements Traceability (요구사항 추적성 관점에서 항공기 탑재 소프트웨어 시험 사례 실패 분석)

  • Kim, Sung-Sub;Cho, Hee-Tae;Lee, Seonah
    • KIPS Transactions on Software and Data Engineering
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    • v.9 no.11
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    • pp.357-366
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    • 2020
  • As the proportion and complexity of software embedded in aircraft increase, risk factors such as mission failure, function failure and performance failure due to software errors also increase. In the mission-critical software systems such as aircraft software, managing requirement traceability is essential to maintain the software systems with minimal period and cost. However, the development company is not accurately complying with the guideline for managing requirement traceability due to various reasons such as development cost and schedule. Therefore, it is not easy to systematically establish and maintain requirement traceability. In the paper, we analyze actual test cases of aviation software systems from the viewpoint of requirements traceability in order to learn if there are failure cases of test cases due to the absence of systematic traceability management activities. We also check the risks associated with the failure cases according to the type and severity of the cases. As a result of analyzing a total of 7 aircraft-mounted software, failure cases could be divided into three types: omission of requirements, lack of connection between requirements and test procedures, and omission of test procedures. There were a total of 18 failure cases, 6 for each type. The numbers of high, middle and low risks were 1, 13 and 4, respectively, where the number of middle risks is largest.

Feasibility of hearing aid gain self-adjustment using speech recognition (말소리 인지를 이용한 보청기 이득 자가 조절의 실현)

  • Yun, Donghyeon;Shen, Yi;Zhang, Zhuohuang
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.1
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    • pp.76-86
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    • 2022
  • Personal hearing devices, such as hearing aids, may be fine-tuned by allowing the users to conduct self-adjustment. Two self-adjustment procedures were developed to collect the listener preferred gains in six octave-frequency bands from 0.25 kHz to 8 kHz. These procedures were designed to allow rapid exploration of a multi-dimensional parameter space using a simple, one-dimensional user control interface (i.e., a programmable knob). The two procedures differ in whether the user interface controls the gains in all frequency bands simultaneously (Procedure A) or only the gain in one frequency band (Procedure B) on a given trial. Monte-Carlo simulations suggested that for both procedures the gain preference identified by simulated listeners rapidly converged to the ground-truth preferred gain profile over the first 20 trials. Initial behavioral evaluations of the self-adjustment procedures, in terms of test-retest reliability, were conducted using 20 young, normal-hearing listeners. Each estimate of the preferred gain profile took less than 20 minutes. The deviation between two separate estimates of the preferred gain profile, conducted at least a week apart, was about 10 dB ~ 15 dB.

Reliability Acceptance Sampling Plans with Sequentially Supplied Samples (시료가 축차적으로 공급되는 상황에서의 신뢰성 샘플링검사 계획)

  • Koo, Jung-Seo;Kim, Min;Yum, Bong-Jin
    • Journal of Korean Institute of Industrial Engineers
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    • v.33 no.1
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    • pp.76-85
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    • 2007
  • A reliability acceptance sampling plan (RASP) consists of a set of life test procedures and rules for eitheraccepting or rejecting a collection of items based on the sampled lifetime data. Most of the existing RASPs areconcerned with the case where test items are available at the same time. However, as in the early stage ofproduct development, it may be difficult to secure test items at the same time. In such a case, it is inevitable toconduct a life test using sequentially supplied samples.In this paper, it is assumed that test items are sequentially supplied, the lifetimes of test items follow anexponential disthbution, failures are monitored continuously, arrival times of test items are known, and thenumber of test items at each arrival time is given. Under these assumptions, RASPs are developed by deter-mining the test completion time and the critical value for the maximum likelihood estimator of the mean lifetimesuch that the producer and consumer risks are satisfied. Then, the developed plans are compared to thetraditional Type-I censored RASPs in terms of the test completion time. Computational results indicate that thetest completion time of the developed RASP is shorter than that of the traditional Type-I censored plan in mostcases considered. It is also found that the superiority of the developed RASP becomes more prominent as theinter-arrival times of test items increase and/or the total number of test items gets larger.

Detection of antibodies in swine serum to Aujeszky's disease virus using agar-gel immunodiffusion test (Agar-gel immunodiffusion test를 이용한 돼지 혈청중 Aujeszky's disease virus 항체 검출에 관한 연구)

  • Cho, Hyo-gueon;Jun, Moo-hyung
    • Korean Journal of Veterinary Research
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    • v.30 no.3
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    • pp.297-307
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    • 1990
  • To establish an agar-gel immunodiffusion (AGID) test for detection of antibodies to Aujeszky's disease virus(ADV) in swine, the precipitating antigens were prepared by four procedures using the Aujeszky's disease virus, NYJ-1-87 strain isolated from the affected piglets in Korea. The optimal condition for AGID test and the properties of the antigens were investigated. To determine the optimal concentration of antigens, four antigens were experimentally prepared by concentrating the viral fluids by 1/30 to 1/200. It was proved that the antigen precipitated with ammonium sulfate at concentration of 1/100 was the most efficient to detect ADV antibodies by AGID test. When the relationship between the concentration of the antigens and the size of precipitating in radial immunodiffusion test was investigated, a high correlation coefficiency at r=0.95 (y=0.23x+23.4) was estimated, In study on the effects of various buffered salt solutions and agars on the sensitivity of AGID test by using the experimental ADV antigens, it was found that 0.05M tris buffer without sodium chloride at pH 7.2 induced the most distinctive precipitating lines, and that there was no significant differences in the sensitivity between the agarose and Noble's special agar. When the efficiency of AGID test was compared with serum neutralization(SN) test, the sensitivity of AGID test was 100% in SN titer over 1 : 16, 91.7% in SN titer of 1 : 8 and 57.1% in SN titer of 1 : 4. The specificity of AGID test compared with the sera with SN titer under 1 : 2 was 98.4%. Protein analysis of the antigens by SDS-PAGE indicated that antigen I and antigen III showed a specific band of polypeptides with molecular weight of 116 K in comparison with the control antigen. Antigen IV, treated with tween-80 and ammonium sulfate, revealed specific polypeptides bands at the molecular weights 45K, 98K and 150 K.

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Trouble Shooting for Fully Automatic Flight Test of Small Scaled Tiltrotor UAV (축소형 틸트로터 무인기의 전자동 비행시험을 위한 문제해결과정)

  • Kang, Young-Shin;Park, Bum-Jin;Yoo, Chang-Sun;Koo, Sam-Ok;Lee, Jang-Ho
    • Aerospace Engineering and Technology
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    • v.8 no.1
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    • pp.1-9
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    • 2009
  • The ground integration test of Smart UAV has been performed according to the flight test plan. The flight test of full scaled model will be performed followed by 4 DOF ground rig test and a tethered hover test. Smart UAV is the first indigenous tiltrotor aircraft which can fly with fast cruise speed and take off or land vertically. In order to prove the flight control law of Smart UAV, the 40% scaled airplane was developed and have been tested. During flight test of small scaled model, many unique and unexpected problems occurred. After clearing these problems, fully automatic flight test was performed successfully. The experiences about many trouble shooting and resolving the problems would be basic material to avoid the unexpected but similar flight test problems hidden behind of the full scaled Smart UAV. This paper presents the detailed procedures of trouble shootings to solve the unique problems which occurred during the flight test of small scaled tiltrotor UAV.

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