• Title/Summary/Keyword: Sensitivity study

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A Study on the Operating Principle of the Light-emitting and -receiving Part of the Photoelectric Sensitivity Tester (광전식감도시험기의 발광부와 수광부 작동원리에 관한 연구)

  • Yoon, Hun-Ju;Kwon, Seong-Pil;Kim, Hyeong-Gweon;SaKong, Seong-Ho
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.04a
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    • pp.151-154
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    • 2008
  • The advanced technical data collected from home and abroad have properly been analyzed, so that they are useful to improve the photoelectric sensitivity tester. The results of this study have quickly been supplied to the related industry. Our research and development team has verified the response characteristics of the light-emitting and -receiving part of the photoelectric sensitivity tester in order to help the local manufacturer to study, develope and produce their photoelectric detectors.

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Human Sensitivity Responses to Vibrotactile Stimulation on the Hand : Measurement of Absolute Thresholds (진동식 촉각 자극에 대한 손의 절대 민감도 반응)

  • Lee, Seong-Il
    • Journal of the Ergonomics Society of Korea
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    • v.17 no.2
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    • pp.1-10
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    • 1998
  • The objective of this study is to investigate hwnan operator's perceptual and psychophysical responses to vibrotactile stimulation on various parts of the hand. Using a small vibrotactile display, five different loci of the hand along with two other mechanical parameters consisting vibrotactile stimulations, which are vibration frequency and number of active contactors, were examined for the effects on absolute thresholds. All test variables were found to have significant effects on thresholds. It was observed that absolute threshold is a function of vibration frequency and number of active contactors. Tactile sensitivity was the greatest at the vibration frequency of 240 Hz, and the fingertip was found to be the most sensitive locus on the hand. The area of stimulation on the hand was also found to be significant in that the sensitivity increased with the number of active contactors. The results of the study generally supported those of other previous studies. It should also be noted, however, that the conclusions from the study should be limited to the absolute sensitivity, not to the suprathreshold intensities of normal everyday contact with the hands.

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A Study on the Structural Relationship of Perceived Value, Price Sensitivity, and Satisfaction between Brand Image and Purchase Intention in Overseas Direct Purchase (해외직접구매 소비자의 브랜드이미지와 구매의도 간 지각된가치, 가격민감도, 만족도의 구조적 관계 연구)

  • Jeong, Boon-Do;Kim, Ji-Hoon
    • Korea Trade Review
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    • v.44 no.6
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    • pp.169-185
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    • 2019
  • The purpose of this study is to analyze the structural relationships of perceived value, price sensitivity, and satisfaction between brand image and purchase intention of consumers who have experience of overseas direct purchase. This study collected questionnaires used to analyze these structural relationships. Using the R's plspm package, we analyzed the PLS (partial least squares) structural equation model. In order to examine the relationship between perceived value and price sensitivity, the research model was modified and analyzed. As a result, not only the adoption of the research hypothesis, but also the goodness of fit was higher than before the research model modifying, and the relationship between perceived value and price sensitivity was further verified. The modified research model has higher academic value, so it is necessary to select it as the final proposal model.

A Study on Discrimination Sensitivity between EEG Patterns under IAPS(International Affective Picture System) Stimuli (시각 감성평가를 위한 뇌파의 민감성에 대한 연구)

  • Hwang, Min-Cheol;Ryu, Eun-Gyeong;Kim, Cheol-Jung
    • Journal of the Ergonomics Society of Korea
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    • v.17 no.1
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    • pp.1-9
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    • 1998
  • The sensitivity of the emotion evoked visually by IAPS was attempted to be defined using EEG(electroencephalogram). Twenty university students were participated in this study. Their EEG was measured and analyzed in terms of frequency range such as delta, theta, alpha and beta wave. The results showed that alpha increased, but delta and beta decreased with positive emotional progress. Inter-variation between alpha and delta in F4 and beta variation in P3 were indicative of the evaluation sensitivity of human emotion.

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Experimental Study on Signal Sensing of a High Sensitive Fiber Optic Hydrophone (실험을 통한 소형 고감도 광섬유 하이드로폰의 감지성능 연구)

  • 김정석;윤형규;설재수
    • Journal of KSNVE
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    • v.9 no.6
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    • pp.1152-1156
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    • 1999
  • In this study, a fiber optic air-backed mandrel hydrophone has been constructed and performance of acoustic signal detection has been measured. The hydrophone is based on a Mach-Zehnder interferometer with 35 m of sensing fiber. The sensitivity is measured up to -128 dB re rad/$\mu$ Pa in range from 1.4 kHz to5 kHz. A system with this design of hydrophone may be applied to detect low frequency underwater acoustic signals.

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Sensitivity Study of Thermal Stresses in Mass Concrete Structures (매스 콘크리트 구조물의 수화열 및 응력 해석의 민감도 분석)

  • 차수원;김광수
    • Journal of the Korean Society of Safety
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    • v.16 no.4
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    • pp.160-167
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    • 2001
  • Cracking in connote structures is one of the main issues of structural design next to ensuring the load-bearing capacity. Thermal analysis is used to prevent thermal mucking, but concrete properties are uncertain variable, and analysis results have uncertainty, too. In this study, sensitivity analysis is performed to investigate the effect of conductivity, specific heal and pouring temperature. The results show that lower conductivity and higher specific heat increase the maximum temperature and maximum tensile stress. The structure with internal restraint is mostly influenced by the change of conductivity and specific heat.

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Calibration of the Pyranometer Sensitivity Using the Integrating Sphere

  • Kim, Bu-Yo;Lee, Kyu-Tae;Zo, Il-Sung;Lee, Sang-Ho;Jung, Hyun-Seok;Rim, Se-Hun;Jang, Jeong-Pil
    • Asia-Pacific Journal of Atmospheric Sciences
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    • v.54 no.4
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    • pp.639-648
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    • 2018
  • The pyranometer for observing the solar radiation reaching the surface of the earth is manufactured by various companies around the world. The sensitivity of the pyranometer at the observatory is required to be properly controlled based on the reference value of the World Radiometric Center (WRC) and the observatory environment; otherwise, the observational data may be subject to a large error. Since the sensitivity of the pyranometer can be calibrated in an indoor or outdoor calibration, this study used a CSTMUSS-4000C Integrating Sphere by Labsphere Inc. (USA) to calibrate the sensitivity of CMP22 pyranometer by Kipp&Zonen Inc. (Netherlands). Consequently, the factory sensitivity of CMP22 was corrected from $8.68{\mu}V{\cdot}(Wm^{-2})^{-1}$ to $8.98{\mu}V{\cdot}(Wm^{-2})^{-1}$, and the result from the outdoor calibration according to the observatory environment was $8.90{\mu}V{\cdot}(Wm^{-2})^{-1}$. After the indoor calibration of the pyranometer sensitivity, the root mean square error (RMSE) of the observational data at the observatory on a clear day without clouds (July 13, 2017) was $7.11Wm^{-2}$ in comparison to the reference pyranometer. After the outdoor calibration of the pyranometer sensitivity based on these results, the RMSE of the observational data was $1.74Wm^{-2}$ on the same day. Periodic inspections are required because the decrease of sensitivity over time is inevitable in the pyranometer data produced at the observatory. The initial sensitivity after indoor calibration ($8.98{\mu}V{\cdot}(Wm^{-2})^{-1}$) is important, and the sensitivity after outdoor calibration ($8.90{\mu}V{\cdot}(Wm^{-2})^{-1})$ can be compared to the data at the Baseline Surface Radiation Network (BSRN) or can be used for various studies and daily applications.

Design Strategies of a Shaver for Men based on Consumers' Sensitive Images of Preference (소비자 선호 감성이미지 기반 남성용면도기 디자인 전략)

  • Lee, Yu-Ri;Yang, Jong-Youl
    • Science of Emotion and Sensibility
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    • v.10 no.3
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    • pp.393-402
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    • 2007
  • The purpose of this study is to provide the design direction based on consumer sensitivity through the structure between product design preferences - sensitivity image - design elements. For the purpose, we selected men's shaver products for this study subject and collected 164 shavers' pictures released between 2001-2007 years. Then, we carried out a pilot test for collection of sensitivity images about shavers, made a survey using semantic differential method and analyzed the survey. According the result, consumers preferred the sensitivity images "luxury, attractive, stable", design elements satisfied the preference images were "form of body is not a circular arcs or a polygon, material is steel, button is push style, and a color of body is not brown." This study can provide a base of the causal relationship between design preferences - sensitivity image - design elements and a design process to predict consumer sensitivity-oriented design.

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Comparison of 99mTc-DMSA Renal Scan and Power Doppler Ultrasonography for the Detection of Acute Pyelonephritis and Vesicoureteral Reflux

  • Bae, Hee Jung;Park, Yong-Hoon;Cho, Jae Ho;Jang, Kyung Mi
    • Childhood Kidney Diseases
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    • v.22 no.2
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    • pp.47-51
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    • 2018
  • Purpose: Urinary tract infection (UTI) is one of the common infectious diseases in children. Several imaging modalities can be used to confirm the presence of acute pyelonephritis (APN). Among them the 99mTcdimercaptosuccinic acid renal scan (DMSA scan) is used as a gold standard for diagnosis. Ultrasonography technology is evolving. Therefore, in this study, we investigated the sensitivity and specificity of Power Doppler ultrasonography (PDU) compared to the results from the previous study. Methods: There were 260 patients included in this study, aged between 1 and 12 months old. The patients were admitted to the Yeungnam University Medical Center between January 2008 and December 2015. All patients underwent both DMSA scan and PDU within 5days of admission. Voiding cystourethrography (VCUG) was performed in 195 patients with abnormal DMSA scan or PDU. Results: The diagnostic sensitivity of APN using PDU was 45.5% and specificity was 85.5% in 260 patients following detection of a defect on DMSA scan that was defined as APN. The diagnostic sensitivity and specificity of PDU for VUR were 65.5 % and 60.1%, respectively. The diagnostic sensitivity and specificity of DMSA scan for VUR were 95.7% and 14.1%, respectively. Conclusion: PDU has a high specificity but low sensitivity, so there are limitations in using it to replace a DMSA scan for the diagnosis of APN in children. DMSA scan and PDU have different sensitivity and specificity in diagnosis of VUR, respectively. Therefore, we suggest that the sensitivity and specificity of each test can be helpful in diagnosing APN and VUR when used in conjunction.

An Empirical Study on Factors Affecting Price Sensitivity and Choice of Internet Bookstores (인터넷 서점유형의 선택에 영향을 미치는 요인에 관한 탐색적 연구)

  • Oh, Jeong-Eun;Lee, Seung-Chang;Lee, Ho-Geun
    • Information Systems Review
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    • v.4 no.2
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    • pp.133-153
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    • 2002
  • Internet lowers the search cost to acquire information about products and sellers price information. Because consumers can easily compare prices among different Internet retailers, the price competition among merchants in Internet has been intensified. For online retailers, it is important to differentiate their sites from competitors based upon services rather than prices. This study investigates which factors influence on consumers price sensitivity in Internet book markets and examines whether consumers price sensitivity has any effect on the type of preferred Internet bookstore (hybrid or pure online book stores). Survey is conducted to empirically investigate the relationship among the various consumer attitudes and price sensitivity. The result shows that price search and price importance have effect on the choice of Internet bookstore. Consumers with higher price sensitivity preferred to purchase books from pure Internet bookstores rather than hybrid (click-and-mortar) bookstores. This study provides an exploratory framework that tries to understand consumer behavior about price sensitivity that might provide some marketing implications to lessen the price competition of Internet retailers.