• Title/Summary/Keyword: CV measurement

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A Critical Evaluation of Dichotomous Choice Responses in Contingent Valuation Method (양분선택형 조건부가치측정법 응답자료의 실증적 쟁점분석)

  • Eom, Young Sook
    • Environmental and Resource Economics Review
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    • v.20 no.1
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    • pp.119-153
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    • 2011
  • This study reviews various aspects of model formulating processes of dichotomous choice responses of the contingent valuation method (CVM), which has been increasingly used in the preliminary feasibility test of Korea public investment projects. The theoretical review emphasizes the consistency between WTP estimation process and WTP measurement process. The empirical analysis suggests that two common parametric models for dichotmous choice responses (RUM and RWTP) and two commonly used probability distributions of random components (probit and logit) resulted in all most the same empirical WTP distributions, as long as the WTP functions are specified to be a linear function of the bid amounts. However, the efficiency gain of DB response compared to SB response were supported on the ground that the two CV responses are derived from the same WTP distribution. Moreover for the exponential WTP function which guarantees the non-negative WTP measures, sample mean WTP were quite different from median WTP if the scale parameter of WTP function turned out to be large.

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Measurement of ECF for $CaSO_4:Dy$ Thermoluminescent Dosimeters ($CaSO_4:Dy$ 열형광선량계의 소자보정인자(ECF) 산출)

  • Lim, Kil-Sung;Kim, Jang-Lyul
    • Journal of Radiation Protection and Research
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    • v.30 no.4
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    • pp.231-236
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    • 2005
  • Dosimeters are manufactured from same process in the manufacturer but the deviation of TL raw counts exists among the dosimeters. TL raw counts are also gradually degrade due to multiple readings and physical abuse. ECF (Element Correction Factor) correct the degradation and deviation of TL raw counts to the average TL raw counts of reference dosimeters. Procedures for producing ECF of thermoluminescent dosimeters were described In detail. ECFs of 319 reference, control and field dosimeters were measured three times and average of three ECF values was calculated. Also, % CV(Coefficient of Variation) of three ECF values was calculated to verify ECF. ECF & % CV distributions for the field and control dosimeters are presented. TL raw counts of field dosimeters, being used about 6 times for the past 3 years, were almost unchanged, but those of control dosimeters being used more frequently, were degraded about 4.7 %.

Changes of Chloroplast Number per Guard Cell pairs of Leaves by Ploidy Level in Nicotiana tabacum L. cv. BY-4 (담배 식물체[Nicotiana tabacum L. cv. BY-4]의 배수성에 따른 공변세포의 엽록체 수 변화)

  • 배창휴;이연희;양덕춘;민경수;김호일;이호연
    • Korean Journal of Plant Tissue Culture
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    • v.28 no.4
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    • pp.179-184
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    • 2001
  • We evaluated a possibility of the use of chloroplast number per guard cell pairs as a measure for ploidy level in the different ploidy levels of tobacco plant (Nicotiana tabacum L. cv. BY-4) . The guard-cell chloroplast numbers of leaves of haploid plant were a half of wild-type plant. Furthermore, the number of chloroplast per guard cell pairs of the leaves of doubled-haploid plant increased in two times compared with that of haploid plant. In addition, the chloroplast number was not changed in the F$_1$ progenies. The change of the chloroplast number by leaf stage was not observed. The results indicate that there is a strong relationship between ploidy level (2x and 4x) and chloroplast number per guard cell pairs. This relationship was also, observed in both in vitro and pot cultured plants. It was determined that the measurement of chloroplast number in guard cells of leaf epidermis is simple to use and less labour intensive, and hence can be considered a practical alternative to the chromosome counting methods or flow cytometry in the tobacco plant.

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The Effect of Korean Medical Complex Treatment on Functional Dyspepsia Patients : Through Measurement of Functional Dyspepsia Symptoms through NDI-K (Nepean Dyspepsia Index-Korean Version), Pressure Pain Threshold through an Algometer (기능성 소화불량 환자에 대한 한의복합치료 효과 : NDI-K(Nepean Dyspepsia Index-Korean version)를 통한 기능성 소화불량증상, algometer를 통한 압력통각역치 측정을 통하여)

  • Rho, Gi-Hwan;Choi, Gyu-Ho;Lee, Sang-Hyun;Choi, Seo-Hyung;Noh, Hyeon-Min
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.36 no.3
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    • pp.100-104
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    • 2022
  • The purpose of this study is to observe the effectiveness of the Korean medical complex treatments for functional dyspepsia (FD). And we observed NDI-K (Nepean dyspepsia index-Korean version) and algometer on acupoints to confirm the treatment effectiveness. In this retrospective study, we investigated 77 patients with FD symptoms who admitted to 00 Korean Hospital for 2 weeks from April 14, 2020 to March 31, 2021. All patietns were treated with herbal medicines, acupuncture, pharmacopuncture, moxa treatment, aroma therapy, So-jeok and So-jeok II therapy. On the day of admission and discharge, NDI-K, algometer on acupoints (CV12, CV10, ST25, ST27, SP14) were examined twice. Among the NDI-K values, all 14 items except for poor breathing were decreased statistically significantly. The algometer values were increased statistically significantly in all acupoints (CV12, CV10, ST25, ST27, SP14). These results suggest that Korean medical treatment can be useful in the treatment of FD.

Comparison of Precision for Available Phosphate Measurement between Lancaster and Soiltek KA-1 Spectrophotometric Method (Lancaster 법과 Soiltek KA-1 분광광도계를 이용한 유효인산 측정법의 정밀도 비교)

  • Hyun, Hae-Nam;Lim, Han-Cheol;Eom, Ki-Cheol;Kim, Yoo-Hak
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.3
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    • pp.268-273
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    • 1999
  • To measure the precision of Soiltek$^{(R)}$ KA-1 spectrophotometric measurement of soil available phosphate, standard deviation, C;V, and relative sensitivity were investigated, comparing to Lancaster method. Available phosphate concentration measured by Soiltek$^{(R)}$ KA-1 spectrophotometric method was highly correlated with Lancaster method($r=0.998^{***}$) and the slop of regression equation was close to 1.0. There were no differences in standard deviation. CV, and relative sensitivity for soil available phosphate concentrations measured by two methods. Regarding to convenience of experimental procedure and instrumental operation, and time saving analysis, Soiltek$^{(R)}$ KA-1 spectrophotometric measurement for soil available phosphate is highly recommended.

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Assessment of Gait Ability of Subjects With Chronic Ankle Instability During an Inter-trial Variability Gait Task According to Changes in Gait Speed

  • Jeonghan Kwon;Jongduk Choi
    • Physical Therapy Korea
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    • v.30 no.4
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    • pp.268-274
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    • 2023
  • Background: Ankle sprains occur frequently among humans who undertake various body movements. Diverse walking environments and dual tasks, that can affect ankle sprains, have been studied. However, there is a lack of research on inter-trial variability according to the changes in gait speed. Objects: The purpose of this study was to compare the adaptive ability of walking between the subjects with chronic ankle instability and healthy adults while performing a walking task with different walking speeds. Methods: In this study, 24 people in the chronic ankle instability group and 24 people in the healthy ankle group were selected as subjects. The length of the pre-measurement and the actual walking measurement were both set to 4.6 m. Once the subjects entered the measurement section, they changed their gait speed according to the randomly assigned speed change. Gait was measured twice and the average value was used for the analysis. Results: The coefficient of variation (CV) of cycle time in subjects with chronic ankle instability showed a significant difference in all cases except when the subjects changed their speed from preferred to slow and from slow to preferred. The CV of step length demonstrated a significant difference in all cases except for the change from slow to preferred and from preferred to fast. The cycle time and step length differential showed a significant difference only when the subjects changed the speed from slow to fast. Conclusion: The subjects with chronic ankle instability were found to have significantly reduced walking adaptability while performing inter-trial variability tasks with different gait speeds compared to healthy subjects.

A General Procedure for Estimating the General Parameter Using Auxiliary Information in Presence of Measurement Errors

  • Singh, Housila P.;Karpe, Namrata
    • Communications for Statistical Applications and Methods
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    • v.16 no.5
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    • pp.821-840
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    • 2009
  • This article addresses the problem of estimating a family of general population parameter ${\theta}_{({\alpha},{\beta})}$ using auxiliary information in the presence of measurement errors. The general results are then applied to estimate the coefficient of variation $C_Y$ of the study variable Y using the knowledge of the error variance ${\sigma}^2{_U}$ associated with the study variable Y, Based on large sample approximation, the optimal conditions are obtained and the situations are identified under which the proposed class of estimators would be better than conventional estimator. Application of the main result to bivariate normal population is illustrated.

Study on the Effect of Acupuncture at Jeonjung($CV_{17}$) on the Heart Rate Variability in Healthy Adults (단중혈(膻中穴) 침자극이 정상 성인의 심박변이도에 미치는 영향)

  • Park, Jin-Soo;Ahn, Min-Seob;Lee, Jeong-Ju;Choi, Byoung-Sun;Park, Min-Cheol;Yang, Hyun-Ju;Park, Ga-Young;Kim, Min-Chul;Jo, Eun-Heui
    • Journal of Acupuncture Research
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    • v.28 no.2
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    • pp.13-25
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    • 2011
  • Objectives : This study was accomplished to investigate the effects of acupuncture at Jeonjung($CV_{17}$) on the heart rate variability(HRV) in healthy adults. And based on that, we tried to find out how acupuncture at Jeonjung($CV_{17}$) effects on the activity and balance of the autonomic nervous system. Methods : We investigated on 74 healthy volunteers consisted of 24 subjects in acupuncture group, 24 subjects in sham acupuncture group and 24 subjects in control group. On the other hand, two volunteers were ruled out by standard of elimination. The study was established by randomized trial. Acupuncture was applied at Jeonjung($CV_{17}$) during 10 minutes in acupuncture group and minimal acupuncture was applied at the same area in sham acupuncture group. No treatment was executed in control group. We measured HRV 3 times : baseline measurement and after treatment in acupuncture group and sham acupuncture group (after rest in control group) twise. The SPSS 15.0 for Windows was used to analyze the data by paired t-test, Wilcoxon signed ranks test (in group) and One-Way ANOVA, Kruskal-Wallis test (between the groups). Results: 1. In acupuncture group, Mean HRT, PSI, Normalized HF decreased significantly. SDNN, Ln (TP), Ln (LF), Ln (VLF), Normalized LF and LF/HF ratio increased significantly. RMSSD, Ln(HF) were not affected. 2. In sham acupuncture group, all indicators were not affected. 3. In control group, mean HRT, Ln(TP) decreased significantly. SDNN, RMSSD, PSI, Ln(LF), Ln(HF), Ln(VLF), normalized LF, normalized HF and LF/HF ratio were not affected. Conclusions : We suggest that acupuncture at Jeonjung($CV_{17}$) increases the activity of autonomic nervous system and makes effects on the balance of the autonomic nervous system.

Vision-based Automatic System for Non-contact Measurement of Morphometric Characteristics of Flatfish

  • Jeong, Seong-Jae;Yang, Yong-Su;Lee, Kyounghoon;Kang, Jun-Gu;Lee, Dong-Gil
    • Journal of Electrical Engineering and Technology
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    • v.8 no.5
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    • pp.1194-1201
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    • 2013
  • This paper introduces a vision-based automatic system (VAMS) for non-contact measurement of morphometric characteristics of flatfish, such as total length (TL), body width (BW), height (H), and weight (W). The H and W are simply measured by a laser displacement and a load cell, respectively. The TL and BW are measured by a proposed morphological image processing algorithm. The proposed algorithm cans measurement, when the tail of flatfish is deformed, and when it is randomly oriented. In the experiment, the average and maximum measurement errors were recorded, and standard deviations and coefficients of variation (CVs) for the measurements were calculated. From those results, when flatfish the TL measurements had an average of 266.844 mm, a standard deviation of 0.351 mm, a CV of 0.131%, and a maximum error of 0.87 mm with straightened flatfish ($TL_A$ : 267 mm, $BW_A$ : 141 mm), and when flatfish of different sizes were measured, the errors in the TL and BW measurements were both about 0.2 %. Using a single conveyor, the VAMS can process up to 900 fishes per hour. Moreover, it can measure morphometric characteristics of flatfish with a TL of up to 500 mm.

Development of Material Deformation Measurement System using Machine Vision (머신 비전을 활용한 재료 변형 측정 기술 개발)

  • E. B. Mok;W. J. Chung;C. W. Lee
    • Transactions of Materials Processing
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    • v.32 no.1
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    • pp.20-27
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    • 2023
  • In this study, the deformation of materials was measured using the video and tracking API of OpenCV. Circular markers attached to the material were selected the region of interests (ROIs). The position of the marker was measured from the area center of the circular marker. The position and displacement of the center point was measured along the image frames. For the verification, tensile tests were conducted. In the tensile test, four circular markers were attached along the longitudinal and transverse directions. The strain was calculated using the distance between markers both in the longitudinal and transverse direction. As a result, the stress-strain curve obtained using machine vision is compared to the stress-strain curve obtained from the DIC results. RMSE values of the strain from the machine vision and DIC were less than 0.005. In addition, as a measurement example, a bending angle and springback measurement according to bending deformation, and a moving position measurement of a punch, a blank holder, and a die by time change were performed. Using the proposed method, the deformation and displacement of the materials were measured precisely and easily.