• Title/Summary/Keyword: Experimental result

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

  • Sung, Kunmin;Jeung, In-Seuck
    • 한국연소학회:학술대회논문집
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    • 2013.06a
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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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Analytical Study on Performance Evaluation of Superdetonative Mode Ram Accelerator (초폭굉 모드 램가속기의 성능해석에 대한 이론적 연구)

  • Sung, Kunmin;Jeung, In-Seuck
    • Journal of the Korean Society of Combustion
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    • v.19 no.1
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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.

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

  • Jin, Joo-Ho;Lee, Sang-Hyun;Lee, Han-Seung
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.345-346
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    • 2009
  • This research focused on large variation of the result of Ca(OH)$_2$ quantity by TG/DTA test or micro-pore size by MIP test. Assume that sample postion has influenced on experimental result, therefore, relationship between sampling position and the experimental result was studied As a result of the research, it is obvious that samples from inside(P-3) shows more Ca(OH)$_2$ and less porosity than samples from outside(P-1).

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Character Classification with Triangular Distribution

  • Yoo, Suk Won
    • International Journal of Advanced Culture Technology
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    • v.7 no.2
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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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    • v.18 no.4
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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.

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

  • Yon, Je-Sun;Lee, Bong-Jun;Ahn, Tae-Young
    • Proceedings of the KIEE Conference
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    • 2003.07b
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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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Effect of Microcurrent Electrostimulation on the Burn of Rats (미세전류 전기자극이 흰쥐의 화상에 미치는 영향)

  • Kim, Se-Hoon;Kim, Jung-Woo;Park, Jang-Sung
    • Journal of the Korean Academy of Clinical Electrophysiology
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    • v.6 no.1
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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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Experimental Verification of Unwinding Behavior of Fiber-Optic Cable and Prediction of High-Speed Unwinding (광 케이블 풀림 거동의 실험적 검증 및 고속 풀림 거동 예측)

  • Kim, Kun Woo;Lee, Jae Wook;Kim, Hyung Ryul;Yoo, Wan Suk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.3
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    • pp.243-250
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    • 2014
  • Fiber-optic cables towed by underwater vehicles have an important role in enhancing the mission capability of a mother ship. In general, fiber optic cables are unwound in water for securing unwinding stability and preventing unwinding-related problems. Therefore, in this study, the numerically simulated result is verified against the experimental result in water, and the cable-unwinding motion is predicted based on the increase in unwinding velocity. The experimental apparatus is composed of a water tank and a winder, and a high-speed camera is used for photographing the cable-unwinding motion. The numerical result defined in the Cartesian coordinate system is solved using a transient-state unwinding equation of motion. The numerical result agrees well with the experimental result, and it can predict cable-unwinding behaviors in according to an increase in the unwinding velocity.

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

  • 김귀분
    • Journal of Korean Academy of Nursing
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    • v.32 no.6
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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.

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

  • 이재봉;김지현;박윤서;선희복
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.2
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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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