• Women's Health Nursing
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• v.14 no.3
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• pp.213-221
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• 2008

Purpose: This study aimed to examine the accuracy and adequacy of research papers reporting statistical testings for correlation and regression. Method: Original research articles utilized correlation and regression analysis were reviewed from the Korean Journal of Women Health Nursing published from the year 2004 to 2006. Thirty-six papers were evaluated in accordance with formatted criteria in respect to an inclusiveness of research title, accuracy of statistical methods and presentation styles, and errors in reporting statistical outcomes. Result: Thirty articles (83.3%) utilized Pearson's correlational analysis, and ten articles did regression analysis. Lack of accurate understanding and interpretation of the statistical method was a main fault. Basic assumptions and diagnostic testings for each statistical method were not performed or described in most of the studies. Some points like consistency of research questions with statistical methods and criteria for sample size were still left out in part. Details of the presentation in the reporting of outcomes were not complied with the guidelines, which need careful concerns of the writers. Errors in English of result tables were found in more than one third of the tables. Conclusion: The outcome would be reflected in the submission guidelines for future writers. To reach the level comparable with internationally recognized nursing journals, concrete knowledge to apply statistical methods should be ensured in the processes of submission, reviews, and editing.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.215-222
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• 2018

This paper reports the development and performance evaluation of a backend system for real-time IVUS (Intravascular Ultrasound) imaging. The developed backend system was designed to minimize the amount of logic and memory usage by means of efficient LUTs (Look-up Tables), and it was implemented in a single FPGA (Field Programmable Gate Array) without using external memory. This makes it possible to implement the backend system that is less expensive, smaller, and lighter. The accuracy of the backend system implemented was evaluated by comparing the output of the FPGA with the result computed using a MATLAB program implemented in the same way as the VHDL (VHSIC Hardware Description Language) code. Based on the result of ex-vivo experiment using rabbit artery, the developed backend system was found to be suitable for real-time intravascular ultrasound imaging.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.904-914
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• 2011

The volumetric errors of CNC machining centers are determined by 21 errors, including 3 linear errors, 6 straightness errors, 3 perpendicular errors, 9 angular errors and non-rigid body errors of the machine tool. It is very time consuming and hard to measure all of these errors in which laser interferometer and other parts are used directly. Hence, as many as 21 separate setups and measurements are needed for the linear, straightness, angular and perpendicular errors. In case of the 5-axis machining centers, two more rotary tables are used. It can make 35 error sources of the movement. Therefore, the measured errors of multi movements of the 5-axis tables are very complicated, even if the relative measured errors are measured. This paper describes the methods, those analyze the error sources of the machining centers. Those are based on shifted diagonal measurements method (SDM), R-test and Double ball bar. In case, the angular errors of machine are small enough comparing with others, twelve errors including three linear position errors, six straightness errors and three perpendicular errors can be calculated by using SDM. To confirm the proposed method, SDM was applied to measuring 3 axes of machine tools and compared with directly measurement of each errors. In addition, the methods for measuring relative errors of multi-axis analysis methods using R-test and Double Ball Bar are introduced in this paper.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.11 s.176
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• pp.135-141
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• 2005

Measurement of five DOF motion errors in a ultra precision feed table was attempted in this study. Yaw and pitch error were measured by using a laser interferometer and roll error was measured by using the reversal method. Linear motion errors in the vertical and horizontal directions were measured by using the sequential two point method. In this case, influence of angular motion errors was compensated by using the previously measured ones by the laser interferometer and the reversal method. The capacitive type sensors and an optical straight edge were used in the reversal method and the sequential two point method. Influence of thermal deformation on sensor jig was investgated and minimized by the periodic measurement according to the variation of room temperature. Deviation of gain between sensors was also compensated using the step response data. 5 DOF motion errors of a hydrostatic table driven by the linear motor werer tested using the measurement method. In the horizontal direction, measuring accuracies for the linear and angular motion were within ${\pm}0.02\;{\mu}m$ and ${\pm}0.04$ arcsec, respectively. In the vertical direction, they were within ${\pm}0.02{\mu}m$ and ${\pm}0.05$ arcsec. From these results, it was found that the introduced measurement method was very effective to measure 5 DOF motion errors of the ultra precision feed tables.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.49-58
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• 2004

The first and perhaps the most critical and perhaps the most important step in the process of predicting future traffic volume in a region (Zone) is to estimate the number of trips generated in from each traffic analysis zone. Most trip generation models for urban transportation planning, and highway in Korea are regression models. In Korea the category analysis has not been tried for last decades since the proper data such as the household travel behavior data have not been collected. Recently, the comprehensive household travel behavior survey such as ${\ulcorner}$1996 The Household Travel Behavior Survey${\lrcorner}$, ${\ulcorner}$2002 The Household Travel Behavior Survey${\lrcorner}$ has been done. In this paper, the cross-classification tables of Seoul Metropolitan Area including the City of Seoul and Kyonggi Province are estimated by the category analysis. The tables are compared with regression models and ${\ulcorner}$2002 The Household Travel Behavior Survey${\lrcorner}$ data in terms of predictive capabilities in Seoul Metropolitan Area. Improvement strategies for trip generation forecast in Seoul Metropolitan Area are proposed.

• Women's Health Nursing
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• v.17 no.2
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• pp.187-194
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• 2011

Purpose: This study investigated the statistical methods and the results had reported correlation/regression analysis in the studies of Korean Journal of Women Health Nursing (KJWHN). Methods: We reviewed 45 studies using correlation/regression analysis for the suitability of the statistical methods and the research purposes, the criteria for analysis of figures, tables and charts had published in the KJWHN from vol 13 (1) in 2007 to vol 15 (4) in 2009. Results: Forty three studies were fitted to their statistical methodology and their research purposes. Eleven studies considered the minimum sample size. Fourteen regression studies used multiple regression and 12 studies used forward method for variable entry. Only one study among the 17 regression studies accomplished scatter plots and residuals examination. Sixteen studies in correlation studies and six studies in regression studies showed some errors in either the title, variables, category of figures, tables and charts. In the regression study, all reported $R^2$ and ${\beta}$ values except one. Conclusion: It was found that there were still statistical errors or articulation errors in the statistical analysis. All reviewers need to be reviewed more closely for detecting errors not only during reviewing process of the manuscript but also periodic publication for the quality of this academic journal.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.3
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• pp.285-291
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• 2014

Recently, many researchers have paid attention to the study on generation of new linked data from tables by using linked open data (e.g. RDF, OWL). This paper proposes a new method for such generation of linked data. A pattern-based method intrinsically has a conflict problem among patterns. For instance, several patterns, mapping a single header of a table into different properties of linked data, conflict with each others. Existing studies have sacrificed precision by applying a statistically dominant pattern or have ignored conflicting patterns to increase precision. The proposed method finds appropriate patterns for all headers in a given table by connecting patterns applied to the headers. Experiments using DBPedia and Wikipedia showed results that conflicts of patterns are effectively resolved by the proposed method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2341-2349
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• 2015

The commonly used Goldschmidt's floating-point divider algorithm performs two multiplications in one iteration. In this paper, a tentative error corrected K'th Goldschmidt's floating-point number divider algorithm which performs K times multiplications in one iteration is proposed. Since the number of multiplications performed by the proposed algorithm is dependent on the input values, the average number of multiplications per an operation in single precision and double precision divider is derived from many reciprocal tables with varying sizes. In addition, an error correction algorithm, which consists of one multiplication and a decision, to get exact result in divider is proposed. Since the proposed algorithm only performs the multiplications until the error gets smaller than a given value, it can be used to improve the performance of a divider unit. Also, it can be used to construct optimized approximate reciprocal tables.

• Informatization Policy
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• v.17 no.2
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• pp.86-103
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• 2010

This paper computes the economic impact of handset subsidies using the recent Input-Output Tables and compares the results with other alternatives which telecommunications companies can choose. The first scenario is that telecommunications companies give handset subsidies to consumers and sales agents. The second is that the companies do not give the subsidies to them, but instead spend the same amount of subsidy on facility investment. The third is that the companies lower the prices of their mobile communications services and consumers spend the saved expenses on other goods and services. The result is that the production, value added, import, job, employment inducement coefficients of the first scenario is larger than those of the second and third scenarios. The reason is as follows. The handset subsidy results in the incentive to consumers for handset purchase or the incentive for sales agents to sell the telecommunication services of the companies. The former has larger production and import inducement effect, and the latter also has larger value-added, job, and employment inducement effect than those of other scenarios.

• KSBB Journal
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• v.18 no.5
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• pp.356-362
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• 2003

This study defines the biotechnology industry, examines its position in the domestic economy, and analyses its structure with I-O tables of year 1985, 1990 and 1995. Structural decomposition analysis is used in order to estimate the impact of different sources of growth. We classifies Korean biotechnology industry into 6 sectors, based on the survey of domestic biotechnology industry by Bioindustry Association of Korea. Empirical results indicate that each sector of bioindustry has various sources of growth and industrial demand has led the growth in all sectors except for food-bio and agriculture-bio. For the growth of the industry, each sector needs to cope with the change of the private demand and to improve the import and export structure.