• Title/Summary/Keyword: R-test

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Color Appearances and Morphological Characteristics of Rice According to the Visual Acceptance (외관 기호도에 의한 쌀의 색택 및 형태관련 특성)

  • Song, Jin;Chun, A-Reum;Kim, Sun-Lim;Kim, Deog-Su;Son, Jong-Rok
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.7
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    • pp.618-623
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    • 2006
  • This study was carried out to select the acceptance test influenced by some quality characteristics of rice, and may provide the basic information on rice grade of appearance quality as distinguished the numerical values. Forty-four Japonica rice varieties mainly cultivated in Korea were evaluated for a consumer acceptance test. Color preferences of rice were highly correlated with appearance quality (r=-0.897**) and redness (r=-0.893**). Especially, appearance quality value resulted from interaction of $redness{\times}yellowness$ values was expected as a specific character used for grade of rice appearance. Shape preferences of rice showed the positive correlation with grain width (r=0.527**) and grain size (r=0.454**). Result of the consumer acceptance test of rice appearance conducted through a cluster analysis revealed five groups. Our study suggests that it may be feasible to be graded by average of quality character among groups, grain width, and grain size in Duncan's multiple range test.

Heat Transfer Characteristics of R-407C During Condensing Inside Horizontal Smooth and Micro-Fin Tubes (수평 평활관 및 전열촉진관내 대체 냉매 R-407C의 응축 열전달 특성에 관한 연구)

  • Roh, Geonsang;Oh, Hookyu
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.2
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    • pp.210-217
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    • 1999
  • This paper reports the experimental results on heat transfer characteristics of R-22 and R-407C(HFC-32/125/134a 23/25/52 wt%) condensing inside horizontal smooth and finned tubes. The test condensers used In the study are double pipe heat exchangers of 7.5 mm ID, 9.5 mm OD smooth tube, and 60 finned micro-fin tube with 8.53 mm ID, 9.53 mm OD. Each of these tubes was 4 000 mm long tubes connected with an U-bend. These U type two-path test tubes are divided In 8 local test sections for the identification of the local condensing heat transfer characterisitcs and pressure drop, U-bend effects on condensing flows. Inlet quality is maintained 1.0, and refrigerant mass velocity is varied from 102.0 to $301.0kg/m^2{\cdot}s$. From the results, it was found that the pressure drop of the R-407C Increased, and heat transfer coefficient decreased compared to those of R-22. In comparison condensing heat transfer characteristics of micro-fm tube with those of smooth tube, increasing of condensing heat transfer coefficient was found outstanding compared to the increasing ratio of pressure drop. Furthermore, pressure drop In U-bend showed at most a 30 % compared to the total pressure drop in the test section.

Experimental study on the strength behavior of cement-stabilized sand with recovered carbon black

  • Chhun, Kean Thai;Choo, Hyunwook;Kaothon, Panyabot;Yune, Chan-Young
    • Geomechanics and Engineering
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    • v.23 no.1
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    • pp.31-38
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    • 2020
  • Soil-cement stabilization is a type of ground improvement method which has been used to improve the engineering properties of soil. The unconfined compression test is the commonly used method to evaluate the quality of the stabilized soil due to its simplicity, reliability, rapidity and cost-effectiveness. The main objective of this study was to evaluate the effect of recovered carbon black (rCB) on the strength characteristic of cement-stabilized sand. Various rCB contents and water to cement ratios (w/c) were examined. The unconfined compression test on stabilized sand with different curing times was also conducted for a reconstituted specimen. From the test result, it was found that the compressive strength of cement-stabilized sand increased with the increase of the rCB content up to 3% and the curing time and with the decrease of the w/c ratio, showing that the optimum rCB concentration of the tested stabilized sand was around 3%. In addition, a prediction equation was suggested in this study for cement-stabilized sand with rCB as a function of the w/c ratio and rCB concentration at 14 and 28 days of curing.

Post-earthquake capacity evaluation of R/C buildings based on pseudo-dynamic tests

  • Kang, Dae-Eon;Yi, Waon-Ho
    • Structural Engineering and Mechanics
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    • v.24 no.1
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    • pp.91-105
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    • 2006
  • In this paper, post-earthquake capacity evaluation method of reinforced concrete buildings was studied. Substructure pseudo-dynamic test and static loading test of first story column in a four-story R/C building was carried out in order to investigate the validity of the evaluation method proposed in the Damage Assessment Guideline (JBDPA 2001). In pseudo-dynamic test, different levels of damage were induced in the specimens by pre-loading, and input levels of seismic motion, at which the specimens reached to the ultimate stage, were examined. From the experimental result, no significant difference in damage levels such as residual crack width between the specimens under static and pseudo-dynamic loading was found. It is shown that the seismic capacity reduction factors ${\eta}$ can provide a reasonable estimation of post-earthquake seismic capacity of R/C buildings suffered earthquakes.

A Study on Developing the Performance Evaluation Indicators of Defense R&D Test Development Projects (국방연구개발 시험개발사업 성과평가지표 개발에 관한 연구)

  • Lee, Hyung-Jun;Kim, Woo-Je;Kim, Chan-Soo
    • IE interfaces
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    • v.23 no.1
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    • pp.78-88
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    • 2010
  • In this paper we develop a model for the performance evaluation of defense R&D test development projects based on analytic hierarchy process. First, evaluation indicators are collected through the related literature survey and a delphi inquiry method. Second, stepwise multiple linear regression is used for developing a hierarchical structure for analytic hierarchy process in the evaluation model, which can make the selected evaluation indicators of the hierarchical structure independent. Also we verify the effectiveness of proposed indicators of the performance evaluation by comparing with the existing evaluation indicators. The developed indicators for the performance evaluation is more reasonable and practical than the previous indicators on defense R&D test development projects.

A study on the characteristics of deterioration in 6.6kV CV cable (6.6kV CV케이블의 경년열화 특성연구)

  • Kim, K.H.;Sun, J.H.;Kim, Y.B.;Cho, Y.O.
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.636-639
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    • 1993
  • This paper is discribed the results of insulation characteristic tests that are DC leakage current, test, tan${\delta}$ test, AC breakdown test and observation of tree in the used 6.6kV CV cables. In the correlation of these tests, the tan${\delta}$ test stands for the main deterioration factor of cable insulation.

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A study on prediction of oil concentration in the R-407C and R-410A refrigeration system (대체냉매 R-407C와 R-410A를 사용하는 냉동시스템의 오일농도 예측에 관한 연구)

  • 이종문;김창년;박영무
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.3
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    • pp.384-390
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    • 1999
  • A vibrating U-Tube decimeter has been evaluated as a sensor for measuring the concentration of oil in the liquid line of a refrigeration system. Calibration and performance tests were conducted under simulated liquid-line conditions for R-407C/POE oil and R-410A/POE oil mixtures in oil concentration from 0 to 15 weight percent. Test temperatures ranged from 20 to 5$0^{\circ}C$. As a result of test, oil concentration correlations are presented in terms of specific gravity at each constant temperature. These equations enable to predict the oil concentration without any extraction of the mixture, and can be applied for R-407C/POE oil and R-410A/POE oil mixtures.

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Reduction of sunroof wind noise using tube-type deflector (튜브형 디플렉터를 이용한 썬루프 바람소리 저감)

  • Shin Seong-ryong;Ih Kang Duck;Jung Seung Gyoon
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.219-220
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    • 2004
  • 최근 중대형 세단이나 SW 차량의 썬루프 개구량이 증대되고 사양의 고급화가 진행되면서 기존의 판형 디플렉터를 대신하여 새로이 튜브형 디플렉터의 이용이 늘어나고 있다. 본 연구에서는 실차 무향 풍동을 이용한 실차 썬루프 바람소리 실험을 통하여 튜브형 디플렉터의 특성을 확인하였다. 튜브형 디플렉터의 성능에 영향을 줄 수 있는 인자들의 최적화를 통하여 초기 설계 사양 및 경쟁차보다 우수한 썬루프 바람소리 성능을 얻을 수 있었다.

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The effect of N-Acyl Groups on the Anticonvulsant Activities of N-Acyl -$\alpha$- amino-N-methylglutarimides (N-Acyl-$\alpha$-aminoglutarimide계 화합물의 항경련 활성에 대한 N-Acyl기의 영향)

  • 손기천;최종원;신은화;박민수
    • YAKHAK HOEJI
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    • v.45 no.1
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    • pp.7-15
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    • 2001
  • For the purpose of defining the effects of N-acyl groups on the anticonvulsant activities of N-acyl-$\alpha$-amino-glutarimides, various (R)- and (S)-N-acyl-$\alpha$-aminoglutarimide were prepared from the corresponding N-Cbz-glutamic acid and were evaluated their anticonvulsant activities in the MES and PTZ test, including their neurotoxicities. Among the tested compounds, only (R) N-cinnamoyl-$\alpha$-amino-N-methylglutarimide showed anticonvulsant activity in the MES and PTZ test. And the other tested compounds was active in the only PTZ test. The order of anticonvulsant activities in the PTZ test was as followes; for the (R) series, N-4-methoxycinnamoyl = cinnamoyl > N-4-nitrobenzoyl > N-benzoyl > N-phenylacetyl; for the (S) series, N-4-methoxycinnamoyl = N-3-nitrobenzoyl > N-4-nitrobenzoyl = N-cinnamoyl = N-phenylacetyl. From the above results, it was conceivable that the substituted N-acyl group had important effects on the anticonvulsant activities of these compounds. However stereoisomeric deferences in the anticonvulsant activities were not exhibited clearly.

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Development of GPS Baseband Chip (GPS Baseband Chip 개발)

  • Cho, Jae-Bum;Lee, Tae-Hyoung;Lee, Yoon-Jick;Heo, Jung-Hun;Jung, Hwi-Sung;Jeong, Jun-Young;Yoon, Suk-Ki;Kim, Hak-Soo;Cho, Dong-Sik;Choi, Hoon-Soon
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2313-2315
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    • 2003
  • This paper presents the development methods which Samsung GPS baseband chip is called S3E4510X. Specification of S3E4510X and design methodology of baseband architecture is presented with a study of their effects. Also GPS core block and software are described in detail. We designed and implemented the test board with RF module for evaluating performance via static test dynamic test and each performance factors using live signal and CPS simulator. Test results show that our development GPS baseband chip have effectively performance for mobile handset Location Based Service (LBS) and its practical use for navigation.

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