• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.296-302
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• 1995

When heteroscedasticity occurs in random effects linear model, the error variance may depend on the values of one or more of the explanatory variables or on other relevant quantities such as time or spatial ordering. In this paper we derive a score test as a diagnostic tool for detecting non-constant error variance in random effefts linear model based on the model expansion on error variance. This score test is compared to loglikelihood ratio test.

• Journal of the Korean Statistical Society
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• v.29 no.2
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• pp.231-245
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• 2000

This paper considers a linear regression model with space and time data in where the disturbances follow spatially correlated error components. We provide the best linear unbiased predictor for the one way error components. We provide the best linear unbiased predictor for the one way error component model with spatial autocorrelation. Further, we derive two diagnostic test statistics for the assessment of model specification due to spatial dependence and random effects as an application of the Lagrange Multiplier principle.

• Journal of Electrical Engineering and Technology
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• v.9 no.4
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• pp.1418-1425
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• 2014

In ultrasonic medical imaging, spatial compounding of images is a technique where ultrasonic beam is steered to examine patient tissues in multiple angles. In the conventional ultrasonic diagnostic imaging, the steering of the ultrasonic beam is achieved electronically using the phased array transducer elements. In this paper, a spatial compounding approach is presented where the ultrasonic probe element is rotated mechanically and the beam steering is achieved mechanically. In the spatial compounding, target position is computed using the value of the rotation axis and the transducer array angular position. However, in the process of the rotation mechanism construction and the control system there arises the inevitable uncertainties in these values. These geometric parameter errors result in the target position error, and the consequence is a blurry compounded image. In order to reduce these target position errors, we present a spatial compounding scheme where error correcting transformation matrices are computed and applied to the raw images before spatial compounding to reduce the blurriness in the compounded image. The proposed scheme is illustrated using phantom and live scan images of human knee, and it is shown that the blurriness is effectively reduced.

• The Korean Journal of Cytopathology
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• v.14 no.2
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• pp.53-59
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• 2003

Fine needle aspiration cytology (FNAC) has been known as a very sensitive and effective method for preoperative diagnosis. We studied cases preoperatively diagnosed by FNAC and confirmed by the histopathologic examination to define the effectiveness of FNAC. A total of 567 cases including breast, thyroid gland, lymph node, and soft tissue confirmed histologically after FNAC were enrolled, among 2,844 FNAC cases from January 1996 to March 2000. Overall sensitivity and specificity of FNAC were 93% and 100%, respectively. Sensitivity and specificity of FNAC by sites or organs were 91% and 100% in breast, 100% and 100% in thyroid, 97% and 100% in lymph node, and 71% and 100% in soft tissue, respectively. Nine cases showed diagnostic discrepancy; eight cases of sampling error and one case of interpretation error. Five cases, diagnosed as fibrocystic change at FNAC but invasive ductal carcinoma after the histopathologic examination, were categorized as sampling error due to the presence of diffuse fibrosis or deep seated location. One case of breast, diagnosed descriptively as atypical ductal and stromal cells suggesting invasive ductal carcinoma at FNAC but malignant phyllodes tumor histologically, was categorized as interpretation error. Other cases of sampling errors were two cases of soft tissue, a case of lymph node, and a case of salivary gland.

• Imaging Science in Dentistry
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• v.35 no.3
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• pp.115-119
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• 2005

Purpose : To evaluate the magnification error percentage in repeatedly taken panoramic radiographs of same patient and machine. Materials and Methods : 92 panoramic radiographs from 46 patients were traced and 30 horizontal and vertical measurements were made with digital sliding caliper. The results were compared with paired t-test. Results : There was no statistically significant difference between the two measurements. The overall difference as percentage error was $6.19\pm5.60\%$. The largest error as $14.61\pm12.44\%$ was found at condylar height 1, and smallest as $1.86\pm1.61\%$ at mandibular height. Overall vertical error excluding condylar height 1 was $3.76\pm3.97\%$, and the horizontal error $6.88\pm5.92\%$. Conclusion . Repeatedly taken panoramic radiographs of the same patient and machine was reliable since there was no significant percentage error difference but the percentage error ranged from $1.86\pm1.61\%\;to\;14.61\pm12.44\%$ indicating the error depends on the measuring site.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.741-746
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• 1998

A severe noise in industrial field can be sometimes generated from unexpected installation error and misunderstanding of industrial machinery. To solve the noise problem, the diagnostic tool is generally applied to identify the noise source and to detect the fault of machinery. And then, the suitable control countermeasure corresponding to the diagnostic results is presented. In this paper, two control cases an noise problem of the Incineration Plant and the Pump are introduced.

• Journal of Drive and Control
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• v.15 no.4
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• pp.30-38
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• 2018

Electronic control units (ECUs) are currently popular, and have evolved further towards the high-end application of autonomous vehicles in the automotive industry. Such digital technologies have also become widespread, in agriculture and construction equipment. Likewise, transmission control of high-speed tracked vehicles is based on the transmission control unit (TCU), performing complex gear change control functions, and diagnostic algorithms (a TCU's self-diagnostic and reporting capability of malfunction data through CAN communication). Since all functions of TCU are implemented by embedded-software, it is hardly possible to analyze specifications by reverse engineering. In this paper a real-time transmission simulator adaptable to TCU is presented, for analysis of diagnosis algorithm and standards. Signal simulation circuits are deliberately designed considering electrical characteristics of TCU inputs and various analysis tools, such as analog input auto scan function, and global output enable switch, are implemented in software. Test results from hardware-in-the-loop simulator verify tolerance time for each error, as well as cause of fault, error reset conditions.

• Journal of Biomedical Engineering Research
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• v.24 no.4
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• pp.247-257
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• 2003

This paper proposes a three-dimensional (3D) segmentation algorithm for extracting a diagnostic object from ultrasound images by using a LoG operator In the proposed algorithm, 2D cutting planes are first obtained by the equiangular revolution of a cross sectional Plane on a reference axis for a 3D volume data. In each 2D ultrasound image. a region of interest (ROI) box that is included tightly in a diagnostic object of interest is set. Inside the ROI box, a LoG operator, where the value of $\sigma$ is adaptively selected by the distance between reference points and the variance of the 2D image, extracts edges in the 2D image. In Post processing. regions of the edge image are found out by region filling, small regions in the region filled image are removed. and the contour image of the object is obtained by morphological opening finally. a 3D volume of the diagnostic object is rendered from the set of contour images obtained by post-processing. Experimental results for a tumor and gall bladder volume data show that the proposed method yields on average two times reduction in error rate over Krivanek's method when the results obtained manually are used as a reference data.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.2
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• pp.23-28
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• 2003

This research explains visualization of diagnostic system of 3D CAD data, IGES (Initial Graphics Exchange Specification), by using JNI(Java Native Interface) to connect between C++ and Java programming. The diagnostic system is to analyze IGES clearly by identifying errors and anomalies with respect to the diagnosis of geometry and topology of entities. The output of the system is IGES file including . error information which can be visualized with different colors by several commercial visualization systems. The paper focuses on the visualization of the result IGES which can be extended to web based application over internet.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.10
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• pp.218-225
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• 2003

A diagnostic system has been developed which reports modeling errors generated when exchanging CAD data using IGES (Initial Graphics Exchange Specification) format. The system determines whether the CAD data contains errors. It also helps to define the criteria for determining the integrity and interoperability of CAD data with downstream applications of another CAD/CAM/CAE/PDM systems. The methodology of our algorithms is to analyze IGES model data by identifying errors and anomalies with respect to the diagnosis of geometry and topology. The GUI (Graphic User Interface) of the developed system helps users to input values and to visualize diagnostic results at real time.