• 제목/요약/키워드: Accuracy Rate

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Analyzing the Effect of Characteristics of Dictionary on the Accuracy of Document Classifiers (용어 사전의 특성이 문서 분류 정확도에 미치는 영향 연구)

  • Jung, Haegang;Kim, Namgyu
    • Management & Information Systems Review
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    • v.37 no.4
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    • pp.41-62
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    • 2018
  • As the volume of unstructured data increases through various social media, Internet news articles, and blogs, the importance of text analysis and the studies are increasing. Since text analysis is mostly performed on a specific domain or topic, the importance of constructing and applying a domain-specific dictionary has been increased. The quality of dictionary has a direct impact on the results of the unstructured data analysis and it is much more important since it present a perspective of analysis. In the literature, most studies on text analysis has emphasized the importance of dictionaries to acquire clean and high quality results. However, unfortunately, a rigorous verification of the effects of dictionaries has not been studied, even if it is already known as the most essential factor of text analysis. In this paper, we generate three dictionaries in various ways from 39,800 news articles and analyze and verify the effect each dictionary on the accuracy of document classification by defining the concept of Intrinsic Rate. 1) A batch construction method which is building a dictionary based on the frequency of terms in the entire documents 2) A method of extracting the terms by category and integrating the terms 3) A method of extracting the features according to each category and integrating them. We compared accuracy of three artificial neural network-based document classifiers to evaluate the quality of dictionaries. As a result of the experiment, the accuracy tend to increase when the "Intrinsic Rate" is high and we found the possibility to improve accuracy of document classification by increasing the intrinsic rate of the dictionary.

Validity of predictive equations for resting energy expenditure in Korean non-obese adults

  • Ndahimana, Didace;Choi, Yeon-Jung;Park, Jung-Hye;Ju, Mun-Jeong;Kim, Eun-Kyung
    • Nutrition Research and Practice
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    • v.12 no.4
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    • pp.283-290
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    • 2018
  • BACKGROUND/OBJECTIVES: Indirect calorimetry is the gold-standard method for the measurement of resting energy expenditure. However, this method is time consuming, expensive, and requires highly trained personnel. To overcome these limitations, various predictive equations have been developed. The objective of this study was to assess the validity of predictive equations for resting energy expenditure (REE) in Korean non-obese adults. SUBJECTS/METHODS: The present study involved 109 participants (54 men and 55 women) aged between 20 and 64 years. The REE was measured by indirect calorimetry. Nineteen REE equations were evaluated for validity, by comparing predicted and measured REE results. Predictive equation accuracy was assessed by determining percent bias, root mean squared prediction error (RMSE), and percentage of accurate predictions. RESULTS: The measured REE was significantly higher in men than in women (P < 0.001), but the difference was not significant after adjusting for body weight (P > 0.05). The equation developed in this study had an accuracy rate of 71%, a bias of 0%, and an RMSE of 155 kcal/day. Among published equations, the $FAO_{weight}$ equation gave the highest accuracy rate (70%), along with a bias of -4.4% and an RMSE of 184 kcal/day. CONCLUSIONS: The newly developed equation provided the best accuracy in predicting REE for Korean non-obese adults. Among the previously published equations, the $FAO_{weight}$ equation showed the highest overall accuracy. Regardless, at an individual level, the equations could lead to inaccuracies in a considerable number of subjects.

Clinicopathological Significance and Diagnostic Accuracy of c-MET Expression by Immunohistochemistry in Gastric Cancer: A Meta-Analysis

  • Pyo, Jung-Soo;Kang, Guhyun;Cho, Hyunjin
    • Journal of Gastric Cancer
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    • v.16 no.3
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    • pp.141-151
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    • 2016
  • Purpose: The aim of the present study was to elucidate the clinicopathological significance and diagnostic accuracy of immunohistochemistry (IHC) for determining the mesenchymal epidermal transition (c-MET) expression in patients with gastric cancer (GC). Materials and Methods: The present meta-analysis investigated the correlation between c-MET expression as determined by IHC and the clinicopathological parameters in 8,395 GC patients from 37 studies that satisfied the eligibility criteria. In addition, a concordance analysis was performed between c-MET expression as determined by IHC and c-MET amplification, and the diagnostic test accuracy was reviewed. Results: The estimated rate of c-MET overexpression was 0.403 (95% confidence interval [CI], 0.327~0.484) and it was significantly correlated with male patients, poor differentiation, lymph node metastasis, higher TNM stage, and human epidermal growth factor receptor 2 (HER2) positivity in IHC analysis. There was a significant correlation between c-MET expression and worse overall survival rate (hazard ratio, 1.588; 95% CI, 1.266~1.992). The concordance rates between c-MET expression and c-MET amplification were 0.967 (95% CI, 0.916~0.987) and 0.270 (95% CI, 0.173~0.395) for cases with non-overexpressed and overexpressed c-MET, respectively. In the diagnostic test accuracy review, the pooled sensitivity and specificity were 0.56 (95% CI, 0.50~0.63) and 0.79 (95% CI, 0.77~0.81), respectively. Conclusions: The c-MET overexpression as determined by IHC was significantly correlated with aggressive tumor behavior and positive IHC status for HER2 in patients with GC. In addition, the c-MET expression status could be useful in the screening of c-MET amplification in patients with GC.

Effect of impression coping and implant angulation on the accuracy of implant impressions: an in vitro study

  • Jo, Si-Hoon;Kim, Kyoung-Il;Seo, Jae-Min;Song, Kwang-Yeob;Park, Ju-Mi;Ahn, Seung-Geun
    • The Journal of Advanced Prosthodontics
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    • v.2 no.4
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    • pp.128-133
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    • 2010
  • PURPOSE. The purpose of this study was to compare the accuracy of the implant master cast according to the type (pick-up, transfer) and the length (long, short) of the impression copings. MATERIALS AND METHODS. The metal master cast was fabricated with three internal connection type implant analogs (Osstem GS III analog), embedded parallel and with $10^{\circ}$ of mesial angulation to the center analog. Four types of impression coping were prepared with different combinations of types (transfer, pick-up) and lengths (long, short) of the coping. The impressions were made using vinyl polysiloxane (one step, heavy + light body) with an individual tray, and 10 impressions were made for each group. Eventually, 40 experimental casts were produced. Then, the difference in the distance between the master cast and the experimental cast were measured, and the error rate was determined. The analysis of variance was performed using the SPSS (v 12.0) program (${\alpha}$= .05), and the statistical significance was set at P < .05. RESULTS. The ANOVA showed that the pick-up type impression coping exhibited a significantly lower error rate than the transfer type. However, no significant difference was observed with respect to the length of the impression coping. Additionally, no significant difference was observed between the parallel and mesial angulated groups. CONCLUSION. Within the limitations of this study, the pick-up type impression coping exhibited a more accurate implant master cast than the transfer type in parallel group. The accuracy of the implant master cast did not differ for different lengths of impression coping of at least 11 mm. Additionally, the accuracy of the implant cast was not different for the parallel and $10^{\circ}$ mesial angulated groups.

Classification accuracy measures with minimum error rate for normal mixture (정규혼합분포에서 최소오류의 분류정확도 측도)

  • Hong, C.S.;Lin, Meihua;Hong, S.W.;Kim, G.C.
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.4
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    • pp.619-630
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    • 2011
  • In order to estimate an appropriate threshold and evaluate its performance for the data mixed with two different distributions, nine kinds of well-known classification accuracy measures such as MVD, Youden's index, the closest-to- (0,1) criterion, the amended closest-to- (0,1) criterion, SSS, symmetry point, accuracy area, TA, TR are clustered into five categories on the basis of their characters. In credit evaluation study, it is assumed that the score random variable follows normal mixture distributions of the default and non-default states. For various normal mixtures, optimal cut-off points for classification measures belong to each category are obtained and type I and II error rates corresponding to these cut-off points are calculated. Then we explore the cases when these error rates are minimized. If normal mixtures might be estimated for these kinds of real data, we could make use of results of this study to select the best classification accuracy measure which has the minimum error rate.

A Study on the Characteristics of Chamdrilling for SCM415 Steel (SCM415강에 대한 캄드릴링 특성연구)

  • Kim, Jin-su
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.5
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    • pp.27-34
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    • 2021
  • This study analyzes machining characteristics and presents optimal cutting conditions by measuring the surface roughness, dimensional accuracy, and dimension straightness based on the feed rate after processing the inner diameter hall of SCM415 steel using an automatic CNC(Computerized Numerical Control) lathe. The testing material was cut using an 11.8 mm-diameter Chamdrill after mounting the 32 mm-diameter round bar on an automatic CNC lathe. The cut depth was set at 3 mm, and the cutting speed was fixed at 1500 rpm. The surface roughness, dimensional accuracy, and dimension straightness of 15 testings were measured by changing the feed rate to 0.05, 0.1, and 0.15 mm/rev, respectively. It was difficult to process more than 15 tests during the maching due to noise or break. Additionally, the optimum cutting of SCM415 steel showed excellent surface roughness in the 10th and 11th of testing at cutting speed and feed speed of 1500 rpm and 0.05 mm/rev, respectively. The dimensional accuracy was measured in three dimensions after drilling, which showed good results with an average range of 0.0138-0.0208 mm. Moreover, the lower the feed speed, the higher the accuracy. Additionally, the measurement results of the dimensional straightness showed that the straightness is the straightness was the best at the 1th and 2th cutting regardless of the feed speed.

Comparing the accuracy of saddle position and traditional position in head-up cardiopulmonary resuscitation (Head-up CPR 시 처치자의 위치에 따른 심폐소생술 정확도 비교)

  • Yoon, Byoung-Gil;Park, Jung-Hee
    • The Korean Journal of Emergency Medical Services
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    • v.23 no.2
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    • pp.99-107
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    • 2019
  • Purpose: This study aimed to identify the position for the most accurate head-up cardiopulmonary resuscitation (CPR) by comparing saddle position CPR (SPCPR) and traditional CPR (TCPR). Methods: Sixty certified persons who completed a basic life support provider course between May 1 and June 21, 2019 were enrolled in the study. The participants were asked to perform 2 minutes of CPR, and the depth of chest compression, rate, position, full release, and hands off time were assessed. Accuracy was evaluated based on data collected from a smart phone application connected to the manikin via bluetooth and analyzed using frequency, percentage, t-test, analysis of variance and ${\chi}^2$. Results: The accuracy of chest compression was statistically significantly higher for SPCPR, 63.03%[${\pm}8.75$] for SPCPR and 55.50%[${\pm}10.17$] for TCPR [t=3.074, p=.003]. The depth of chest compression was statistically significantly greater for SPCPR, 4.51cm[${\pm}0.45$] for SPCPR and 4.16cm[${\pm}0.61$] for TCPR [t=2.503, p=.015]. The rate of chest compression was statistically significantly higher for TCPR, 105/min[${\pm}10.79$] for SPCPR and 111/min[${\pm}11.57$] for TCPR [t=-2.008, p=.049]. Accuracy of position of chest compression was statistically significantly higher for SPCPR, 96.10%[${\pm}13.73$] for SPCPR and 79.93%[${\pm}30.34$] for TCPR [t=2.659, p=.011]. Accuracy of full release was higher with SPCPR, with 86.30%[${\pm}30.53$] for SPCPR and 71.10%[${\pm}36.05$] for TCPR, but the difference was not statistically significant [t=1.762, p=.083]. Conclusion: Saddle position CPR was found to be more accurate than TCPR in the performance of manual head-up CPR.

Computerized bone age estimation system based on China-05 standard

  • Yin, Chuangao;Zhang, Miao;Wang, Chang;Lin, Huihui;Li, Gengwu;Zhu, Lichun;Fei, Weimin;Wang, Xiaoyu
    • Advances in nano research
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    • v.12 no.2
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    • pp.197-212
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    • 2022
  • The purpose of this study is to develop an automatic software system for bone age evaluation and to evaluate its accuracy in testing and feasibility in clinical practice. 20394 left-hand radiographs of healthy children (2-18 years old) were collected from China Skeletal Development Survey data of 1998 and China Skeletal Development Survey data of 2005. Three experienced radiologists and China-05 standard maker jointly evaluate the stages of bone development and the reference bone age was determined by consensus. 1020 from 20394 radiographs were picked randomly as test set and the remaining 19374 radiographs as training set and validation set. Accuracy of the automatic software system for bone age assessment is evaluated in test set and two clinical test sets. Compared with the reference standard, the automatic software system based on RUS-CHN for bone age assessment has a 0.04 years old mean difference, ±0.40 years old in 95% confidence interval by single reading, a 85.6% percentage agreement of ratings, a 93.7% bone age accuracy rate, 0.17 years old of MAD, 0.29 years old of RMS; Compared with the reference standard, the automatic software system based on TW3-C RUS has a 0.04 years old mean difference, a ±0.38 years old in 95% confidence interval by single reading, a 90.9% percentage agreement of ratings, a 93.2% bone age accuracy rate, a 0.16 years of MAD, and a 0.28 years of RMS. Automatic software system, AI-China-05 showed reliably accuracy in bone age estimation and steady determination in different clinical test sets.

On a Study of Measurement Method of Utterance Velocity for the Reduction of Transmission Rate in CELP Vocoder. (LSP 파라미터를 이용한 발성측정법)

  • 장경아;배명진
    • Proceedings of the IEEK Conference
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    • 2000.11d
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    • pp.199-202
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    • 2000
  • Speaking Rate has variety depends on the situation and habit of speakers. It has been many studied about speaking rate In speaker recognition. The study of speaking rate in speech recognition is one of considerable matter when It is recognized the speakers and it is measured by many speech data base and complicate estimation for accuracy. In this paper, conventional vocoder process the speech signal when encoding and transmitting without regard to speaking rate so in order to apply the speaking rate for vocoder It should be considered the simpler algorithm and less computation amount than the conventional method of speaking rate used In speech recognition. We proposed the speaking rate algorithm which is used the simple parameter with Line Spectrum Pair (LSP). The proposed peaking rate method is measured by the information of LSP in speech. We measured the variety rate of phenomenon about utterances which have different velocity, respectively. As a result, It has distinct variation rate of phenomenon between utterances uttered fast and slow and the rate is 42.8% higher in case of uttered fast than in case of uttered slow.

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A Study on the Position Accuracy Improvement Applying the Rectangular Navigation in the Hyperbolic Navigation System Area. (쌍곡선항법시스템을 이용한 직각항법에 의한 측위정도 향상에 관한 연구)

  • 김우숙;김동일;정세모
    • Journal of the Korean Institute of Navigation
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    • v.13 no.1
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    • pp.1-10
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    • 1989
  • Nowadays Hyperbolic Navigation System-LORAN, DECCA, OMEGA, OMEGA-is available on the ocean, and Spherical Navigation System, GPS (Global Positioning System) is operated partially. Hyperbolic Navigation System has the blind area near the base line extention because divergence rate of hyperbola is infinite theoretically. The Position Accuracy is differ from the cross angle of LOP although each LOP has the same error of quantity. GDOP(Geometric Dilution of Precisoin) is used to estimate the position accuracy according to the cross angle of LOP and LOP error. Hyperbola and ellipse are crossed at right angle everywhere. Hyperbola and ellipse are used to LOP in Rectangular Navigation System. The equation calculating the GDOP of rectangular Navigation System is induced and GDOP diagram is completed in this paper. A scheme that can improve the position accuracy in the blind area of Hyperboic Navigation System using the Rectangular Navigation System is proposed through the computer simulation.

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