• 제목/요약/키워드: Experimental result

검색결과 13,395건 처리시간 0.05초

초폭굉모드 램가속기의 성능에 대한 이론적 연구 (Analytical Study on Performance of Superdetonative Mode Ram Accelerator)

  • 성근민;정인석
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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    • pp.77-80
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    • 2013
  • An analytical study on performance of superdetonative mode ram accelerator was conducted for understanding the S225 experimental result of ISL. It would be noticeable that ISL S225 experimental result could be analytically simulated with the assumptions of inlet shockwave, equilibrium combustion chemistry, temperature dependent specific heat, and C-J oblique detonation in superdetonative operation mode. As result, the S225 experiment could be affected by heat of aluminum. Also, this study showed that the improper assumption, like isentropic assumption on shockwave, or constant specific heat on combustion, might cause misunderstanding about experimental result.

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초폭굉 모드 램가속기의 성능해석에 대한 이론적 연구 (Analytical Study on Performance Evaluation of Superdetonative Mode Ram Accelerator)

  • 성근민;정인석
    • 한국연소학회지
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    • 제19권1호
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    • pp.1-10
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    • 2014
  • An analytical study on performance evaluation of superdetonative mode ram accelerator was conducted for understanding the experimental result. The quasi-one dimensional continuum, momentum, energy equations were solved under the assumption of inviscid flow. It would be noticeable that experimental result could be analytically simulated with the assumptions of inlet shockwave, temperature dependent specific heat, and additional aluminum combustion due to ablation of aluminum projectile in superdetonative operation mode. The acceleration of ram accelerator was comparable to experimental result with the consideration of the additional aluminum combustion energy by ablation of projectile. As result, the experimental result with the aluminum projectile could be affected by heat of aluminum.

시멘트 경화체 시료의 채취 위치가 정량분석 결과에 미치는 영향에 관한 실험적 연구 (An Experimental study on the effect that sampling position of cement matrix influences Quantitative Analysis result)

  • 진주호;이상현;이한승
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.345-346
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    • 2009
  • 본 연구는 TG/DTA, MIP 장비를 활용한 콘크리트의 미세정량분석시, Ca(OH)$_2$량 및 미세공극구조 분석 결과값의 편차가 큰 것에 주목하여, 시료의 채취 위치가 분석결과에 영향을 미친다고 판단하여 시료의 채취 위치에 따른 미세정량분석 결과를 평가하였다. 그 결과 시료의 채취 위치에 따라 외부(P-1)에서 내부(P-3)일수록 Ca(OH)$_2$이 증가하며 공극량은 감소하는 것을 확인하였다.

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Character Classification with Triangular Distribution

  • Yoo, Suk Won
    • International Journal of Advanced Culture Technology
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    • 제7권2호
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    • pp.209-217
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    • 2019
  • Due to the development of artificial intelligence and image recognition technology that play important roles in the field of 4th industry, office automation systems and unmanned automation systems are rapidly spreading in human society. The proposed algorithm first finds the variances of the differences between the tile values constituting the learning characters and the experimental character and then recognizes the experimental character according to the distribution of the three learning characters with the smallest variances. In more detail, for 100 learning data characters and 10 experimental data characters, each character is defined as the number of black pixels belonging to 15 tile areas. For each character constituting the experimental data, the variance of the differences of the tile values of 100 learning data characters is obtained and then arranged in the ascending order. After that, three learning data characters with the minimum variance values are selected, and the final recognition result for the given experimental character is selected according to the distribution of these character types. Moreover, we compare the recognition result with the result made by a neural network of basic structure. It is confirmed that satisfactory recognition results are obtained through the processes that subdivide the learning characters and experiment characters into tile sizes and then select the recognition result using variances.

A Study on the Propagation of Measurement Uncertainties into the Result on a Turbine Performance Test

  • Cho, Soo-Yong;Park, Chanwoo
    • Journal of Mechanical Science and Technology
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    • 제18권4호
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    • pp.689-698
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    • 2004
  • Uncertainties generated from the individual measured variables have an influence on the uncertainty of the experimental result through a data reduction equation. In this study, a performance test of a single stage axial type turbine is conducted, and total-to-total efficiencies are measured at the various off-design points In the low pressure and cold state. Based on an experimental apparatus, a data reduction equation for turbine efficiency is formulated and six measured variables are selected. Codes are written to calculate the efficiency, the uncertainty of the efficiency, and the sensitivity of the efficiency uncertainty by each of the measured quantities. The influence of each measured variable on the experimental result is figured out. Results show that the largest uncertainty magnification factor (UMF) value is obtained by the inlet total pressure among the six measured variables, and its value is always greater than one. The UMF values of the inlet total temperature, the torque, and the RPM are always one. The uncertainty percentage contribution (UPC) of the RPM shows th, lowest influence on the uncertainty of the turbine efficiency, but the UPC of the torque has the largest influence to the result among the measured variables. These results are applied to find the correct direction for meeting an uncertainty requirement of the experimental result in the planning or development Phase of experiment, and also to offer ideas for preparing a measurement system in the planning phase.

개방형 DC-DC 컨버터의 손실 분석에 관한 연구 (A Study on Loss Analysis of Open-Frame Type DC-DC Converter)

  • 연제선;이봉준;안태영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1193-1195
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    • 2003
  • In this paper, to analyze efficiency characteristic, one of important factors in design of DC-DC converter prototype, theoretically derived power loss of individual components generating in DC-DC converter and compared theoretical results with experimental results. For evaluation of results, active clamp type Forward DC-DC converter with synchronous rectifier was composed of experimental converter. Efficiency result measured in experimental converter was compared with theoretical efficiency result derived in this paper. In comparative result, a fact that derived theoretical value and experimental value comparatively correspond have been able to verify.

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미세전류 전기자극이 흰쥐의 화상에 미치는 영향 (Effect of Microcurrent Electrostimulation on the Burn of Rats)

  • 김세훈;김정우;박장성
    • 대한임상전기생리학회지
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    • 제6권1호
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    • pp.81-89
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    • 2008
  • Purpose: This study aims to examine effect of microcurrent electrostimulation on burn healing by electric intensity and of which the electric intensity on the acute burn being cured with microcurrent electrostimulation therapy. Methods: 28 Sprague Dawley Rats is classified into a control group of 8 rats, an experimental group I of 10 rats and an experimental group II of 10 rats. The control group is not cured, the experimental group I is exposed to 10 Hz, and $100{\mu}A$ with microcurrent electrostimulation, and the experimental group II is exposed to 10 Hz, $300{\mu}A$ for 15 minutes a day. The next day, 2th, 4th, and 6th day after rats is burned. Result: There are not significant differences of length change of the burn cure between the control group, the experimental group I, and the experimental group II by a period. However, systematically hair follicle cell on the 2th day and epidermal cell on the 6th day turn up in the experimental group I, and the experimental group II. Inquiry: Nancy(1994) did not obtain the desired result when the skin of a pig is exposed to 0.1 Hz, and $100{\mu}A$ for wound healing. In the result of the study, when burn length is measured on the 2th, 4th, and 6th to see the length change of acute burn, there is not significant differences among 3 groups. Conclusion: Statistically, there is not significant differences of the length change between 3 groups. However, systematically the burn is cured faster in the experimental group I, and the experimental group II than in the contrast group.

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광 케이블 풀림 거동의 실험적 검증 및 고속 풀림 거동 예측 (Experimental Verification of Unwinding Behavior of Fiber-Optic Cable and Prediction of High-Speed Unwinding)

  • 김건우;이재욱;김형렬;유완석
    • 대한기계학회논문집A
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    • 제38권3호
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    • pp.243-250
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    • 2014
  • 유도체의 발사로 인해 스풀로부터 풀리는 광 케이블은 모함과의 통신을 통해 작전 수행 능력을 향상시키는 역할을 한다. 일반적으로 광 케이블의 풀림은 거동의 안정성 확보 및 풀림 불량 방지를 위하여 수중에서 진행된다. 따라서 본 연구에서는 실험을 통해 스풀로부터 풀리는 광 케이블의 거동특성을 확보하고 이를 풀림 거동 해석 결과와 비교함으로써 해석의 신뢰성을 검증한다. 실험 장치의 구성은 수조와 감김 장치로 구성되며, 고속카메라를 통해 케이블의 풀림 거동을 촬영하였다. 해석결과를 제시하기 위한 과도 상태 운동 방정식은 직교 좌표계를 사용하여 정의한 뒤, 실험 결과와의 비교를 통해 해석 결과의 타당성을 검증하였으며, 풀림 속도의 증가에 따른 풀림 거동을 예측하였다.

암환자의 불안관리를 위한 이압요법 적용 효과 (The Effect of Auricular Acupressure Therapy on Anxiety of Cancer Pateint)

  • 김귀분
    • 대한간호학회지
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    • 제32권6호
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    • pp.888-896
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    • 2002
  • The purpose of this study wsa to necessitate auricular acupressure therapy as an independent nursing intervention on cancer paitents by confirming its effectiveness. Method: The experimental study was unequivalently controlled pre-post measure study. The subjects were 40 cancer patients who were hospitalized in K medical center in Seoul. The experimental group (20) and the control group (20) were randomly assigned. As measured tools, Spielberger's State-trait Anxiety (1976) measured tool by Kim's transplation (1978). The auricular acupressure therapy was applied to experimental group, and the pre-post measure was performed to both group. The data was analyzed by using SPSS computer program that included descriptive statistics, 2-test, and t-test. Result: 1) The experimental group with the auricular acupressure therapy showed lower trait anxiety scores in comparison with the control group (t= 8.036, p=.000). 2) The experimental group which applied the auricular acupressure therapy showed lower state anxiety scores in comparison with the control group (t= 19.616, p=.000). This result showed that cancer patients with the auricular acupressure therapy applied cancer patients decreased state anxiety and trait anxiety. Therefore , effectiveness of the auricular acupressure therapy was confirmed through this study. Conclusion: According to the result, anxiety of cancer pateint should be decreased and controlled by the auricular acupressure therapy as independent nursung intervension. In addition, the auricular acupressure therapy will provide effective independent nursing intervention that will decrease anxiety on patient with other disease and will improve quality of their lives.

GA-Fuzzy Algorithm에 의한 세탁기 모터의 제어 (Control of the Washing Machineos Motor by the GA-Fuzzy Algorithm)

  • 이재봉;김지현;박윤서;선희복
    • 한국지능시스템학회논문지
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    • 제5권2호
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    • pp.3-12
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    • 1995
  • A controller utilizing fuzzy logic is developed to control the speed of a motor in a washing machine by choosing an appropriate phase. Due to the hardship imposed on obtaining a result from a relation established for inputs, present speed and present rate of speed, and ouput, a phase, of the system that can be tested against an experimental result, it is impossible to apply a genetic algorithm to fine-tune the fuzzy logic controller. To avoid this difficulty, a proper assumption that the parameters of an if-part of a primary fuzzy logic controller have a functional relationship with an error between computed values and experimental ones in made. Setting up of a fuzzy relationship between the parameters and the errors is then achieved through experimentally obtained data. Genetic Algorithm is then applied to this secondary fuzzy logic controller to verify the fuzzy logic. In the verification process, the primary fuzzy logic controller is used in obtaining experimental results. In this way the kind of difficulty in obtaining enough experimental values used to verify the fuzzy logic with genetic algorithm is gotten around. Selection of the parameters that would produce the least error when using the secondary fuzzy logic controller is done with applying genetic algorithm to the then-part of the controller. In doing so the optimal values for the parameters of the if-part of the primary fuzzy logic controller are assumed to be contained. The experimental result presented in the paper validates the assumption.

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