• Title/Summary/Keyword: $T_2{^*}$ measurement

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An Analysis on the status of Measurement Investment in Korean Industry (한국산업의 계측투자실태분석)

  • Kim, Dong-Jin;Nam, Gyeong-Hui
    • Journal of Korean Society for Quality Management
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    • v.20 no.2
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    • pp.76-93
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    • 1992
  • The purpose of this study, by surveying the status of firms, measurement-related investment and the defect rate, is to analyze the effect of measurement-related investment and to propose a scheme of efficient measurement-related investment which reduces the defect rate. For this project we obtain the data of the status of the measurement-related investment and the defect rate of 928 firms in Korean manufacturing industry by mailing survey. One of our results shows that the firms which have measurement standard laboratory, i.e, which invest in measurement-related area comparatively high, have the defect rate about 0.8% lower than those firms which don't have measurement standard laboratory. Also we find that the small-and-middle size firms have worse measurement-related facility than the large firms and the firms in the heavy-chemical industry have higher measurement-related investment effect than the firms in the light industry.

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Optimal Rates of Convergence in Tensor Sobolev Space Regression

  • Koo, Ja-Yong
    • Journal of the Korean Statistical Society
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    • v.21 no.2
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    • pp.153-166
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    • 1992
  • Consider an unknown regression function f of the response Y on a d-dimensional measurement variable X. It is assumed that f belongs to a tensor Sobolev space. Let T denote a differential operator. Let $\hat{T}_n$ denote an estimator of T(f) based on a random sample of size n from the distribution of (X, Y), and let $\Vert \hat{T}_n - T(f) \Vert_2$ be the usual $L_2$ norm of the restriction of $\hat{T}_n - T(f)$ to a subset of $R^d$. Under appropriate regularity conditions, the optimal rate of convergence for $\Vert \hat{T}_n - T(f) \Vert_2$ is discussed.

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Performance Test of 2-Dimensional PIV and 3-Dimensional PIV using Standard Images (표준화상을 이용한 2차원 PIV와 3차원 PIV계측 및 성능비교검정)

  • Doh, D.H.;Hwang, T.G.;Song, J.S.;Baek, T.S.;Pyun, Y.B.
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.646-651
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    • 2003
  • Quantitative performance test on the conventional 2D-PIV and the hybrid angular 3D-PIV (Stereoscopic PIV) was carried out. LES Data sets on an impinging jet which are provided on the webpage(http://www.vsj.or.jp/piv) for the PIV Standard Project were used for the generation of virtual images. The generated virtual images were used for the 2D-PIV and 3D-PIV measurements. The measurement results showed that the results obtained by 2D-PIV on average values are closer to the LES data than those obtained by 3D-PIV, but the turbulent properties obtained by 2D-PIV are largely underestimated than those obtained by 3D-PIV.

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A Study on the Measurement of the Normal Tracheal Length in Korea adults (한국성인의 기관 길이 측정에 관한 연구)

  • 나명훈
    • Journal of Chest Surgery
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    • v.28 no.8
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    • pp.766-771
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    • 1995
  • The trachea is defined as the airway from the inferior border of the cricoid cartilage to the top of the carinal spur. This paper would confirm the normal tracheal length of Korean adults through the actual measurement using the fiberoptic bronchoscopy. The subjects of this study were 25 patients, 13 males and 12 females between the age of 20 to 69 without abnormality on the neck, trachea, mediastinum and lung pharenchyme on the preoperative chest X-ray, who received the operations from the period of July to September, 1994. For those patients who had heart diseases, the cardiothoracic ratio was below 50%. The measurement was performed on the patients with endotracheal intubation under the general anesthesia in supine and neutral position. The tracheal length was calculated by the difference between the length from the tip of the endotracheal tube [E-tube to carina and to the needle which was inserted into the E-tube at the lower border of the palpated cricoid cartilage, by inserting the broncoscopy through the E-tube. The result was as follow : 1 The measured tracheal length for men was 11.8 0.2 cm[mean standard deviation and women was 10.5 0.3 cm, and that was longer than this [p<0.01 . The average was 11.2 1.0 cm and the standard error was 0.20 cm. 2 According to the correlation between the tracheal length to weight, height[Ht , age, and body surface area[BSA respectively, the Ht [p=0.003 , age [p=0.055 , and the BSA[p=0.017 were significant, while weight was not [p=0.314 . 3 From the regression analysis of the tracheal length[T.L. to the Ht, Age, and the BSA which were significant, the following equation was derived.i Ht : T.L.= -1.29 + 0.076 x Ht [P=0.003 ii Age: T.L.= 10.04 + 0.028 x Age [P=0.055 iii BSA : T.L.= 5.60 + 3.48 x BSA [P=0.017 iv In multi-regression : T.L. = -4.15 + 0.034 x Age + 0.085 x Ht [P=0.0002]

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Effects of Kangaroo Care on Growth in Premature Infants and on Maternal Attachment (캥거루식 돌보기가 미숙아의 성장과 모아애착에 미치는 효과)

  • Jang, Me-Young
    • Child Health Nursing Research
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    • v.15 no.4
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    • pp.335-342
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    • 2009
  • Purpose: This study, using a pre-post test design of non-equivalence comparative group, was done to determine effects of Kangaroo care (KC) on growth in premature infants and on maternal attachment (MA). Methods: Fifty-three premature infants were assigned to the KC (24) or control group (CG) (29). Data were collected from July 2007 to June 2008. KC was given for 60 min at a time, Monday, Wednesday, and Friday for 10 times. Weight, height, and head circumference (HC) of premature infants were checked before the program started. Following the initial measurement, the program was given and measurements were taken again at the end of the program. For measurement of attachment between mother and infant, data collection was done using structured self-reported questionnaires. Results: KC group had a higher weight (t=2.565, p=.013), height (t=2.182, p=.034) and HC (t=2.468, p=.017) than the CG. Compared to the CG, the KC had significantly higher scores in MA (t=2.026, p=.048). Conclusion: The results of this study suggest that the practice of KC in the nursing environment might actively promote attachment between mother and infant as well as acceleration of growth for premature infants as one of the most efficient nursing intervention.

Temperature-Range-Dependent Optimization of Noninvasive MR Thermometry Methods (온도범위에 따른 비침습적 자기공명 온도측정방법의 최적화)

  • Kim, Jong-Min;Kumar, Suchit;Jo, Young-Seung;Park, Joshua Haekyun;Kim, Jeong-Hee;Lee, Chulhyun;Oh, Chang-Hyun
    • Journal of Biomedical Engineering Research
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    • v.36 no.6
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    • pp.241-250
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    • 2015
  • Noninvasive temperature monitoring is feasible with Magnetic Resonance Imaging (MRI) based on temperature sensitive MR parameters such as $T_1$ and $T_2$ relaxation times, Proton Resonance Frequency shift (PRFs), diffusion, exchange process, magnetization transfer contrast, chemical exchange saturation transfer, etc. While the temperature monitoring is very useful to guide the thermal treatment such as RF hyperthermia or thermal ablation, the optimization of the MR thermometry method is essential because the range of temperature measurement depends on the choice of the measurement methods. Useful temperature range depends on the purpose of treatment methods, for example, $42^{\circ}C$ to $45^{\circ}C$ for RF hyperthermia and over $50^{\circ}C$ for thermal ablation. In this paper, MR thermometry methods using $T_1$ and $T_2$ relaxation times and PRFs-based MR thermometry are tried on a 3.0 T MRI system and their results are reported and compared. In addition, the scanning protocol and temperature calculation algorithms from $T_1$ and $T_2$ relaxation times and PRFs are optimized for the different temperature ranges for the purpose of RF hyperthermia and/or thermal ablation.

Properties of Photoluminescience for AgInS2/GaAs Epilayer Grown by Hot Wall Epitaxy

  • Lee, Sang-Youl;Hong, Kwang-Joon
    • Transactions on Electrical and Electronic Materials
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    • v.5 no.2
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    • pp.50-54
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    • 2004
  • The AgInS$_2$epilayers with chalcopyrite structure grown by using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on the AgInS$_2$/GaAs was derived as the Varshni's relation of E$\_$g/(T) = 2.1365 eV - (9.89${\times}$10$\^$-3/ eV/K) T$^2$/(2930+T eV). After the as-grown AgInS$_2$/GaAs was annealed in Ag-, S-. and In-atmosphere, the origin of point defects of the AgInS$_2$/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of $V_{Ag}$, $V_s$, $Ag_{int}$, and $S_{int}$ obtained from PL measurement were classified to donors or accepters type. And, we concluded that the heat-treatment in the S- atmosphere converted the AgInS$_2$/GaAs to optical p-type. Also, we confirmed that the In in the AgInS$_2$/GaAs did not form the native defects because the In in AgInS$_2$did exist as the form of stable bonds.

[ $T_2$ ]-relaxation Time Measurement of ex vivo $^1H$ MR Metabolite Peaks for Evaluation of Human Stomach Cancer

  • Mun Chi-Woong;Choi Ki-Sueng;Shin Oon-Jae;Yang Young-Ill;Chang Hee-Kyung;Hu Xiaoping;Eun Chung-Ki
    • Journal of Biomedical Engineering Research
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    • v.27 no.2
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    • pp.53-58
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    • 2006
  • In this study, transverse relaxation time (T2) measurement and the evaluation of the characteristics of the spectral peak related to stomach tissue metabolites were performed using ex vivo proton magnetic resonance spectroscopic imaging (MRSI) at 1.5-T MRI/S instruments. Thirty-two gastric tissues resected from 12 patients during gastric cancer surgery, of which 19 were normal tissue and 13 were cancerous tissue, were used to measure the $T_2$ of the magnetic resonance spectroscopy (MRS) peaks. The volume of interest data results from the MRSI measurements were extracted from the proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and were statistically analyzed. MR spectra were acquired using the chemical shift imaging (CSI) point resolved spectroscopy (CSI-PRESS) technique with the parameters of pulse repetition time (TR) and echo times (TE) TR/(TE1,TE2)=1500 msec/(35 msec, 144 msec), matrix $size=24{\times}24$, NA=1, and voxel $size=2.2{\times}2.2{\times}4mm^3$. In conclusion, the measured $T_2$ of the metabolite peaks, such as choline (3.21ppm) and lipid (1.33ppm), were significantly decreased (p<0.01 and p<0.05, respectively) in the cancerous stomach tissue.

Turbidity Calibration of Borehole Roughness Measurement System (BKS-LRPS) Usable in Water (수중에서 사용가능한 굴착공 벽면거칠기 측정 시스템(BKS-LRPS)의 굴착공 내 혼탁도 보정에 관한 연구)

  • Park, Bong-Geun;Choi, Yong-Kyu;Kim, Myung-Hak;Kwon, Oh-Kyun;Nam, Moon-S.
    • Journal of the Korean Geotechnical Society
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    • v.24 no.10
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    • pp.25-32
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    • 2008
  • Based on recent studies, the side resistance of rock socketed drilled shafts was affected by unconfined compressive strength of rock, socket roughness, rock types and joints, and initial normal stress. Especially, the socket roughness was affected by rock types and joints, drilling methods, and diameters of pile. In this study, a new roughness measurement system (BKS-LRPS, Backyoung-KyungSung Laser Roughness Profiling System) usable in water was developed. Based on the laboratory model tests, an EMD (Effective Measurement Distances) according to various turbidity was proposed as $EMD=1149.2{\times}T_{b}^{-0.64}$.

Annealing effects of AgInS$_2$/GaAs Epilayer grown by Hot Wall Epitaxy

  • K. J. Hong;Park, C.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.823-827
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    • 2001
  • The AgInS$_2$epilayers with chalcopyrite structure grown by using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on the AgInS$_2$/GaAs was derived as the Varshni's relation of Eg(T)=2.1365 eV-(9.89${\times}$10$\^$-3/ eV)T$^2$/(2930+T). After the as-grown AgInS$_2$/GaAs was annealed in Ag-,S-, and In-atmosphere, the origin of point defects of the AgInS$_2$/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of V$\_$Ag/, V$\_$s/, Ag$\_$int/, and S$\_$int/ obtained from PL measurement were classified to donors or acceptors type. And, we concluded that the heat-treatment in the S-atmosphere converted the AgInS$_2$/GaAs to optical p-type. Also, we confirmed that the In in the AgInS$_2$/GaAs did net from the native defects because the In in AgInS$_2$did exist as the form of stable bonds.

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