• Title/Summary/Keyword: quantitative evaluation method

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Evaluation of Friction Shear Factor By the Lubricating Methods in Warm Forging (온간 단조에서 윤활 분사 방법에 따른 마찰 상수값의 평가)

  • 정덕진;김동진;김병민
    • Transactions of Materials Processing
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    • v.10 no.4
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    • pp.319-328
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    • 2001
  • Quantitative evaluation of the tribological conditions at the tool-workpiece interface in metal forming is usually accomplished by the ring compression test. This paper describes an experimental investigation into friction factor under warm forming conditions according to the lubricants and the lubricating methods using the ring compression test. Four different lubricants, two water based graphite and two oil based graphite lubricants, and three different lubricating methods were applied in the experiments. Calibration curves with the friction shear factor were obtained using FEM analysis and verified by the experimental results. The influence of lubricant and lubricating methods on friction are discussed. In the ring compression test, the lower friction factor got to spray the oil based lubricant on die and billet in warm forging temperature.

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A Study on the Evaluation of the Corrosive Environment of Reinforcement Bar by Concrete Layer Resistivity (콘크리트 층간비저항에 의한 철근의 부식환경 평가에 관한 연구)

  • Lim, Young-Chul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2012.11a
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    • pp.43-44
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    • 2012
  • Deterioration factors such as CO2 and chloride ions cause steel corrosion in RC structures. The diffusion of these factors depends on the water content in concrete. To examine the moisture condition of concrete, this research considers the availability of the steel effect ratio, which is calculated by Resistivity Estimation Model (REM). It is concluded that the steel effect ratio is expected to be available as a quantitative evaluation method in the assessment of concrete layer resistivity.

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DEVELOPMENT OF NUCLEAR ENERGY AND RADIATION TEXTBOOKS FOR ELEMENTARY, MIDDLE, AND HIGH SCHOOL STUDENTS

  • Han, Eun Ok;Kim, Jae Rok;Choi, Yoon Seok;Lochhead, James
    • Journal of Radiation Protection and Research
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    • v.40 no.3
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    • pp.132-146
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    • 2015
  • To develop tailored elementary, middle, and high school textbooks suitable for understanding the nuclear energy and radiation, quantitative and qualitative research was carried out in parallel, which included nine steps to ensure the validity of content and structure. The elementary, middle, and high school students wanted to acquire information used in their daily lives, including the definition of nuclear energy and radiation, principles and status of nuclear power generation, and information about irradiated food, medical radiation, and radiation in life. In the evaluation of the effects of textbook contents according to the educational requirements of each school level, high suitability frequencies (>80%) were shown for the human character, education goals, curriculum goals, evaluation method, and education time. At some levels, the high suitability frequencies (>70%) were shown for the education grade, education type, and textbook type.

Spectral Characteristics and Nasalance Scores of Hypernasality in Patient with Cleft Palate

  • Soh, Byung-Soo;Shin, Hyo-Keun;Kim, Hyun-Gi
    • Speech Sciences
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    • v.12 no.1
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    • pp.27-35
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    • 2005
  • Differential instrumentation for the diagnoses of individuals with Cleft palate has been used to objectively measure speech problems. The Cepstrum Method was used to study the vocal tract transfer function. The vocal tract transfer function and the source spectrum should be considered in the evaluation of nasal resonance. The aim of this study was to collect quantitative data on the acoustic Instrumentation used for evaluating hypernasality. Normal subjects (9 male, 21 female; 37 male children, 20 female children) and individuals with VPI (13 male, 8 female; 16 male children, 9 female) participated in this study. The vowel /i/ was selected to gauge the severances of hypernasality Spectral and Cepstral studies using CSL was used to identify the acoustic characteristics. Cepstrum analysis shows significant differences in quefrency and amplitude. The quefrency of normal groups was shorter than that of the VPI groups, while the amplitude of normal groups was lower than that of the VPI groups. This may have significance in the evaluation 'of nasal resonance.

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A Corrosion Resistance Evaluation of Welded AISI 304 Stainless Steel by Electrochemical Methods. (전기화학적 방법에 의한 AISI 304 스테인리스강 용접부의 내식성 평가)

  • 백신영;김관휴
    • Journal of Advanced Marine Engineering and Technology
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    • v.14 no.1
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    • pp.83-89
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    • 1990
  • Electrochemical methods have been proposed as non-destructive, rapid and quantitative means for determining the degree of sensitization associated with Chromium depleted zones surrounding precipitates of Cr carbide and formation of secondary phase in stainless steel. In this study, the specimen of AISI 304 stainless steel and its welded sections, which welded by TIG, MIG, $CO_2$ and ARC, were tested corrosion resistance by electrochemical methods in 0.5N HCl and 1N $H_2SO_4$ with or without 0.01N KSCN. The results were confirmed that electrochemical methods could be used as a test method of corrosion resistance evaluation for the welded AISI 304 stainless steel.

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Integrity evaluations of bogie frame using ultrasonic-fractography analysis (초음파-파면해석에 의한 대차 프레임의 건전성 평가)

  • 윤인식;권성태;정우현;박덕신;김경국
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.461-467
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    • 2000
  • This study proposes the integrity evaluation of bogie frame using ultrasonic waves-fractography analysis. Analysis objectives in this study are to investigate fracture planes of damaged zone by the A-scan method. The surface condition of fracture plane shows degree of degradation by stress concentration. The detection of the natural defects in bogie frame is performed using the characteristics of echodynamic pattern in ultrasonic signal. Results of ultrasonic testing agree fairly well with those of actual fracture plane. In quantitative fractography analysis, microstructures of actual fracture plane turned out to be intergranular and transgranular fracture, Proposed ultrasonic-fractography analysis in this study can be used for the integrity evaluation of the bogie frame

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Failure Evaluation of The Digital Substation Based on Fault Tree Analysis (FTA에 기반한 디지털 변전소의 고장 분석)

  • Kim, Sung-Hun;Park, Ji-yeol;An, Yong-Ho;Kim, Seok-Kon;Lee, Seung-Hak;Lee, Dong-Ju
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.553-554
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    • 2015
  • This paper presents the selection method of Minimal Cut Sets(MCS) for substation reliability evaluation. We used the Quality solution in order to model the FT for the substation equipment. Quantitative analysis is performed to estimate the probability of top event occurrence and unreliability of the substation component. In this result, it means that reliability indices which can be predict get electricity services and better maintenance in substation management.

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A Digital Signal Processing System for Analysis of Skeletal Muscle EMG Signal (골격근의 근전도 신호 분석을 위하 디지탈 신호처리 시스템의 설계)

  • 전철완
    • Journal of Biomedical Engineering Research
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    • v.17 no.2
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    • pp.155-164
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    • 1996
  • In the clinical environment, measurements of some characteristics of the skeletal muscle are currently used to assess the severity of a neuromuscular disease or in some cases to assist in making a diagnosis. But a quantitative method of evaluation has not yet been introduced satisfactorily. In this paper, the skeletal EMG(biceps muscle, masseter muscle) analysis has been processed both in the time and in the frequency domain by designing the digital signal processing system based on pentium PC and transputer (IMS 7805). The experiment have been performed in five normal subjects, and various parameters have been statistically tested and compare4 As a results, the effective parameters obtained for the evaluation of skeletal EMG electrical activity are turn analysis, MiTi, MiTa, IEMG, PDF in the time domain, and are mean frequency, median frequency, skewness, kurtosis, muscle fatigue slope in the frequency domain. The designed H/W and S/W in this study can be used effectively for the establishment of EMG data base and for clinical research.

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Data envelopment analyses on evaluating efficiencies of satellite communication and broadcasting R&D outcomes in Korea

  • Ahn, Jae-Kyoung;Ahn, Do-Seob;Ku, Bon-Jun
    • Journal of Satellite, Information and Communications
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    • v.3 no.2
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    • pp.54-59
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    • 2008
  • Traditionally R&D evaluation has been performed by experts who can understand the contents of the study area very well. Recently extensive application of quantitative evaluation methods have been attempted for introducing the administrative management system that poses greater importance on records and results. More objective reviews on the R&D outcomes are called for gaining public supports. In this paper a bibliometrical analysis is to be performed to evaluate satellite communication and broadcasting public R&D outcomes for last 7 years. Data envelopment analysis method is selected for evaluating the efficiencies of multiple outputs (papers, patents, royalties, technology transfers) where multiple inputs (number of researchers and R&D expenses) are given. R&D outcomes from 22 research institutes are being compared and satellite communication and broadcasting R&D efforts turn out to be highly efficient.

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Wall Thickness Measurement of Respiratory Airway in CT Images: Signal Processing Aspects

  • Park, Sang-Joon;Kim, Jong-Hyo;Kim, Kwang-Gi;Lee, Sang-Ho
    • Proceedings of the IEEK Conference
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    • 2007.07a
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    • pp.279-280
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    • 2007
  • Airway wall thickness is an important bio-marker for evaluation of pulmonary diseases such as stenosis, bronchiectasis. Nevertheless, an image-based analysis of the airway tree can provide precise and valuable airway size information, quantitative measurement of airway wall thickness in CT images involves various sources of error and uncertainty. So we have developed an accurate airway wall measurement technique for small airways with three-dimensional (3-D) approach. To illustrate performance of these techniques, we used airway phantom that consisted of 4 acryl tubes with various inner and outer diameters. Results show that evaluation of interpolation and deconvolution methods of airways in 3-D CT images, and significant improvement over the full-width-half-maximum method for measurement of not only location of the luminal and outer edge of the airway wall but airway wall thickness.

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