• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.2
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• pp.542-558
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• 2023

A digital focus index (DFI) is a value used to determine image focus in scientific apparatus and smart devices. Automatic focus (AF) is an iterative and time-consuming procedure; however, its processing time can be reduced using a general processing unit (GPU) and a multi-core processor (MCP). In this study, parallel architectures of a minimax search algorithm (MSA) are applied to two DFIs: range algorithm (RA) and image contrast (CT). The DFIs are based on a histogram; however, the parallel computation of the histogram is conventionally inefficient because of the bank conflict in shared memory. The parallel architectures of RA and CT are constructed using parallel reduction for MSA, which is performed through parallel relative rating of the image pixel pairs and halved the rating in every step. The array size is then decreased to one, and the minimax is determined at the final reduction. Kernels for the architectures are constructed using open source software to make it relatively platform independent. The kernels are tested in a hexa-core PC and an embedded device using Lenna images of various sizes based on the resolutions of industrial cameras. The performance of the kernels for the DFIs was investigated in terms of processing speed and computational acceleration; the maximum acceleration was 32.6× in the best case and the MCP exhibited a higher performance.

• The Journal of Internal Korean Medicine
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• v.36 no.3
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• pp.228-235
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• 2015

Objectives: The aim of this study was to find an effective medical device to detect cold sensation of hands. Methods: Patients with cold sensation of hands (N=42) were recruited in July 2013. We surveyed patients’ general characteristics, severity of cold sensation, body temperature in Nogung (PC8) and Hyeopbaek (LU4) measured with a digital thermometer, digital infrared thermal imaging, and pulse wave velocity. Results: The relation between severity of cold sensation and temperature in Nogung (PC8) and Hyeopbaek (LU4) was statistically significant. The results showed a higher correlation of severity of cold sensation with Nogung (PC9) than with Hyeopback (LU4) temperature. No other indices were statistical significant. Conclusions: Measuring the Nogung (PC9) temperature is most reasonable for assessing the severity of cold sensation of hands. To generalize this result, however, a large-scale study is warranted.

• Journal of Digital Convergence
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• v.6 no.2
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• pp.41-53
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• 2008

This research is to redefine the concept of Good School and to validate an effective Good Secondary School Scale in Kyung-gi Province and Seoul. As statistical methods, SPSS 13.0 and AMOS 5.0 were used. Item Analysis and Exploratory Factor Analysis(EFA) were conducted to test the reliability of items and the factor structure. And Confirmatory Factor Analysis(CFA) was conducted to test the validity and fitness of the Good School Scale. The outcomes are as follows: First, six factors(school environment, curriculum, teacher, school-based management system, director) will increase the good schooling effectiveness. Second, As a result of Confirmatory Factor Analysis(CFA), the goodness of fit indices(GFI AGFI, CFI, RMSEA) demonstrate statistically significance and fitness of the model. The final Good School Scale supports 6 Good School Factors obtained in main test. Therefore, we can say that this scale can be used as a valid instrument to measure a real Good Schooling Effectiveness at the secondary school situation in Korea.

• International Journal of Contents
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• v.6 no.1
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• pp.26-34
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• 2010

This paper is on the premise that we need objective and measurable researches on quality evaluation of serious game for users' correct selection of games fitting for their purposes, for development of competitive high-quality game, and for stable growth of game industry. At first, we looked into various characteristics of serious game, read the present situation of game market, and proposed the necessity of quality evaluating model for serious game. To guarantee the objectivity of the proposed models, we compared and analyzed various proposals of standard model on the basis of international standard quality-evaluating model, ISO/IEC 9126 S/W. And so we extracted quality-evaluating items for serious game that composed of 8 evaluating areas and 25 sub-attributes, and presented quality-evaluating indices of each area. The proposed quality-evaluating model was added 2 areas and 8 sub-attributes to the international standard model, and the validity of the extracted items' was verified by expert group's questionnaire. Accordingly, we expect that this paper will increase game users' satisfaction, promote the development of high-quality games, and contribute to continuous growth in serious game market.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.209-214
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• 2004

Time Domain Reflectometry with multiplex system has been installed to configure the spatial and temporal characteristics of soil moisture in a mountainous hillslope. An intensive surveying was performed to build a refined digital elevation model and flow determination algorithms with inverse surveying have been applied to establish an efficient soil monitoring system. Steady state wetness index, quasi-dynamic wetness index and fully dynamic wetness index have been calculated. Continuous monitoring of soil moisture data were analyized with wetness indices. Limitations and hydrological interpretations of this approach have beer discussed.

• Journal of Korea Water Resources Association
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• v.34 no.4
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• pp.391-401
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• 2001

Several curvature parameters, solar radiation parameter and topographic flow generation parameters have been summarized and calculated to predict the spatial distribution of soil moisture content. The spatial distribution of soil moisture data can be obtained using Global Positioning System(GPS) and portable soil moisture monitoring equipment, Theta-Probe. Correlation analysis has been performed between the parameters of soil moisture prediction and measured data of soil moisture. Multiple regression analysis of soil moisture prediction shows the potential capability and limitations of existing methods of digital terrain analysis.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.81.2-81.2
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• 2011

Motivated by recent attempts to derive geomagnetic activity from hourly mean data in long term studies, we test the recursive Kalman filter method to obtain the regular solar variation curve of the geomagnetic field. Using a simple algorithm, we are able to assign a quiet day curve to every day separately, without the need for additional input parameter(s) to define the geomagnetically quiet days. We derive a digital counterpart AhK of the analog range index Ak at the subauroral Sodankyl$\ddot{a}$ station and compare it to the earlier digital estimate Ah and the local Ak index. We find that the new method outperforms the former estimate in every aspect studied and provides a robust, straightforward manner of estimating and verifying the manually scaled Ak index, based on readily available hourly values. The model is independent of sampling; thus, for shorter term studies where high-sampling data are available, more accurate estimates can also be obtained when needed. Therefore, in contrast to other recent approaches, we do not provide a method to quantify irregular activity directly but derive the actual quiet day curves in the traditional manner. In future applications the same algorithm may be used to define a wide variety of geomagnetic indices (such as Ak, Dst, or AE).

• Journal of Digital Convergence
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• v.9 no.6
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• pp.165-172
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• 2011

In this paper, we introduce an integrated performance evaluation model defined by the three indices (evaluation index for each evaluation stage, performance viewpoint, and performance type) and analyze the utilization and satisfaction of the seven public u-IT services implemented from 2008 to 2009 using the proposed model. From the performance results of the public u-IT services, it was found out that most of the research goals initially set by the public u-IT service support projects were satisfied. Furthermore, we suggest improvement directions and promotion strategies of future projects.

• The KIPS Transactions:PartC
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• v.18C no.4
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• pp.255-264
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• 2011

TV-Anytime is an XML-based standard for description of PVR and digital broadcast services. It is referenced by many standards of digital broadcast service for their schemas and delivery protocols of contents guide. Although its readability and extensibility, TV-Anytime has a big problem which generates massive documents due to its text-based description method. Therefore, various encoding algorithms have been proposed to reduce the size of XML documents. This paper proposes efficient metadata encapsulation architecture based on the optimization information generated at server-side to minimize XML documents. Advanced indexing method is also proposed to reduce resources needed to encapsulate indices and to receive metadata with fast and explicit mechanism.

• Current Optics and Photonics
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• v.6 no.2
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• pp.161-170
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• 2022

Three-dimensional (3D) geometric models are introduced to correct vignetting, and a downhill simplex search is applied to determine the coefficients of a 3D model used in digital microscopy. Vignetting is nonuniform illuminance with a geometric regularity on a two-dimensional (2D) image plane, which allows the illuminance distribution to be estimated using 3D models. The 3D models are defined using generalized polynomials and arbitrary coefficients. Because the 3D models are nonlinear, their coefficients are determined using a simplex search. The cost function of the simplex search is defined to minimize the error between the 3D model and the reference image of a standard white board. The conventional and proposed methods for correcting the vignetting are used in experiments on four inspection systems based on machine vision and microscopy. The methods are investigated using various performance indices, including the coefficient of determination, the mean absolute error, and the uniformity after correction. The proposed method is intuitive and shows performance similar to the conventional approach, using a smaller number of coefficients.