• Journal of Electrical Engineering and Technology
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• v.3 no.2
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• pp.224-234
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• 2008

Multi-phase machines can be used in variable speed drives. Their applications include electric ship propulsion, 'more-electric aircraft' and traction applications, electric vehicles, and hybrid electric vehicles. Multi-phase machines enable independent control of a few numbers of machines that are connected in series in a particular manner with their supply being fed from a single voltage source inverter(VSI). The idea was first implemented for a five-phase series-connected two-motor drive system, but is now applicable to any number of phases more than or equal to five-phase. The number of series-connected machines is a function of the phase number of VSI. Theoretical and simulation studies have already been reported for number of multi-phase multi-motor drive configurations of series-connection type. Variable speed induction motor drives without mechanical speed sensors at the motor shaft have the attractions of low cost and high reliability. To replace the sensor, information concerning the rotor speed is extracted from measured stator currents and voltages at motor terminals. Open-loop estimators or closed-loop observers are used for this purpose. They differ with respect to accuracy, robustness, and sensitivity against model parameter variations. This paper analyses operation of an MRAS estimator based sensorless control of a vector controlled series-connected two-motor five-phase drive system with current control in the stationary reference frame. Results, obtained with fixed-voltage, fixed-frequency supply, and hysteresis current control are presented for various operating conditions on the basis of simulation results. The purpose of this paper is to report the first ever simulation results on a sensorless control of a five-phase two-motor series-connected drive system. The operating principle is given followed by a description of the sensorless technique.

• The KIPS Transactions:PartD
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• v.17D no.1
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• pp.77-86
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• 2010

Recently, Enterprise Architecture (EA) has emerged as the important keyword in both private and public sectors. With this phenomenon, there are tremendous need for the measures of EA functions, one of the key EA research variables, to provide academic insights and accumulate research findings in this area. Thus far, multiple definitions and concepts for EA functions exist, causing confusion among observers. Thus, in order to clarify the conceptual meaning behind the term "functions of EA" once and for all, this study reviews previous literature and provides conceptual definition. Then, we identify 24 items and rigorously develop and validate the measurement instrument for EA functions, which results in five domains: Infrastructure Systemization, Integration Management, IT Governance Support, Development and Operation Management, and Investment Management.

• The Korean Journal of Pain
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• v.20 no.2
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• pp.123-129
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• 2007

Background: Postoperative pruritus following the administration of epidural narcotics is a very common and undesirable side effect. Therefore, we evaluated the use of a combination of naloxone and sufentanil via patient controlled epidural analgesia to determine if the incidence of pruritus was decreased when compared to the use of sufentanil alone. Methods: Patients scheduled for subtotal gastrectomy under general anesthesia were enrolled in a prospective, double-blinded and randomized trial. All patients received a $20{\mu}g$ epidural bolus of sufentanil in 5 ml of 0.2% ropivacaine. Following administration of the epidural, patients in the sufentanyl group (S) received a continuous epidural comprised of sufentanil ($0.75{\mu}g/ml$) in 0.2% ropivacaine, whereas patients in the naloxone group (N) received an epidural infusion comprised of naloxone ($4{\mu}g/ml$) and sufentanil ($0.75{\mu}g/ml$) in 0.2% ropivacaine. The infusion rate, demand dose and lockout interval were 5 ml/hr, 0.5 ml and 15 minutes respectively. Next, the occurrence of postoperative analgesia and side effects were evaluated by blinded observers. Results: The incidence of pruritus (47.4% versus 20.0%, P = 0.013) and nausea (42 .1 % versus 20.0%, P = 0.043) were lower in group N than in group S. In addition, there were no significant differences observed in the visual analogue scale, the incidence of vomiting or the incidence of sedation. Furthermore, epidural infusion of naloxone at $0.25-0.4{\mu}g/kg/hr$ did not affect the requirement for postoperative sufentanil. Conclusions: Epidural naloxone reduces epidural sufentanil induced pruritus and nausea without reversing its analgesic effects.

• Journal of Broadcast Engineering
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• v.8 no.4
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• pp.399-409
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• 2003

In this paper, we present an Event Reporting which is one of the major items of MPEG-21 and exemplify two digital data broadcasting use case scenarios, and according1y we propose the Event Reporting message structure for MPEG-21 broadcasting contents that is based on these use case scenarios. Every interaction with a Digital Item in the multimedia framework can be called an Event. The need to standardize Event Reporting within the Multimedia Framework arise from the need to monitor and communicate amongst Peers and Users the Events relating to Digital Items and/or the programs and devices that operate on them at any given time. However, there are a number of difficulties in providing an accurate report about an Event. Different observers of the Event may have vastly different perspectives. In this paper, we describe a structure and vision of the Event Reporting. Besides we show the activities on MPEG-21 Event Reporting standardization.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.6
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• pp.267-272
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• 2016

Microscope cell image is an important indicator for obtaining the biological information in a bio-informatics fields. Since human observers have been examining the cell image with microscope, a lot of time and high concentration are required to analyze cell images. Furthermore, It is difficult for the human eye to quantify objectively features in cell images. In this study, we developed HCS algorithm for automatic analysis of cell image using an OpenCV library. HCS algorithm contains the cell image preprocessing, cell counting, cell cycle and mitotic index analysis algorithm. We used human cancer cell (MKN-28) obtained by the confocal laser microscope for image analysis. We compare the value of cell counting to imageJ and to a professional observer to evaluate our algorithm performance. The experimental results showed that the average accuracy of our algorithm is 99.7%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.369-369
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• 2007

The physical and visual evaluation of the identical X-rays are analyzed for medical image clarity with CD-RAD Phantom on this study. The method of measurement is to research CD-RAD by X-rays and to acquire images through image processing equipment, the image analyses are carried out by physical evaluation with statistical method through CD-RAD analyser program, and the visual evaluation of the identical X-rays is carried out by blind test for 20 observers. The result of it is that IQF value of the physical evaluation of Contrast-detail curve is 25 and IQF value of the visual evaluation is 30, so it is revealed that the physical evaluation is superior to the visual one. The special qualities of medical images have much importance of the transmission capacity of information to the image analyser, so it is concluded that 0비ective methods of the physical and visual analyses should be carried out side by side.

• Journal of Veterinary Clinics
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• v.37 no.4
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• pp.169-174
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• 2020

The purpose of this study was to establish normal values for the thoracic limb joint reference angles in Shih Tzu dogs and to describe the standardized CT methodology for measuring the joint reference angle of the humerus. Five pairs of thoracic limbs of Shih Tzu dogs were collected for the CT scans in this study. Three blinded observers measured the joint reference angle of the humerus and radius for each dog by using CT scans in the frontal, sagittal, and axial planes. The means (± SDs) for the average of the right and left humeral joint reference angles were as follows: mMPHA, 83.74 ± 3.95°; mLDHA, 85.04 ± 2.57°; mCaPHA, 46.75 ± 2.20°; mCrDHA, 79.47 ± 1.97°; and HTA, 19.16 ± 2.38°. Means (± SD) for the average of right and left of the radial joint reference angles were as follows: aMPRA, 85.04 ± 1.58°; aLDRA, 87.59 ± 1.37°; aCrPRA, 84.60 ± 1.46°; aCdDRA, 84.27 ± 1.79°; and RTA, 20.91 ± 3.00°. The intraclass correlation coefficients (ICCs) of the joint reference angles for the inter- and intraobserver reliability were good to excellent, except those for the mCrHA and HTA were moderate. Our results suggest that the method of measuring joint reference angles of other long bones by using CT can be applied to thoracic limbs and can extract valid values for one specific breed.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.5
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• pp.1121-1129
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• 1988

An economic and efficient system for measuring drop sizes was developed. Pattern recognition technique was used with conventional oil-bath sampling and photographic method. The system was designed to measure and count relatively large number of drops in a very short time, and also to filter out abnormal images such as drops in contact or overlap as well as odd-shaped foreign materials. In this measuring system, most important error originates from the process of converting the original image to the binary image. If the photograph contains a large number of spray drops, the relative size of the pixel to the drops is not infinitesimally small; thus the proper choice of threshold level to convert the original image to the binary image becomes very important. In present case, most of the images lay in one of the two separate bands of brightness level and the arithmetic mean of the most popular brightness levels from each band was chosen as the threshold level. Present image processing system reduces the subjective error by the observers in counting and measuring drops and turns out to be substantially effective. The processing time can be further reduced by improving the hardware system concerned with the digital image coding.

• Journal of Korean Neurosurgical Society
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• v.39 no.4
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• pp.256-259
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• 2006

Objective : Having a reliable and reproducible measurement technique to measure the sagittal contour in vertebral fractures is paramount to clinical decision making. This study is designed to determine the most reliable measurement technique in osteoporotic vertebral compression fracture. Methods : Fifteen lateral radiographs of thoracic and lumbar fractures were selected and measured on two separate occasions by three spine surgeons using six different measurement techniques [Centroid, Harrison Posterior Tangent Methods and 4 different types of modified Cobb method]. The radiograph quality was assessed and the center beam location was determined. Statistical analysis including ANOVA for repeated measures was carried out using the SAS software [v 8.0]. Results : The inter and intraobserver variance of the Cobb method 4 and Harrison posterior tangent method were significantly lower than the other four methods. The intraobserver correlation coefficients were the most consistent using the Cobb method 4 [0.982]. which was followed by the Harrison posterior tangent [0.953] and Cobb methods 1 [0.874]. The intraobserver agreement [% of repeated measures within 5 degrees of the original measurement] ranged from 42% to 98% for each technique for all three observers, with the Cobb method 4 showing the best agreement [97.8%] followed by the Harrison posterior tangent method [937%]. Conclusion : The Cobb method-4 and Harrison posterior tangent methods, when applied to measuring the kyphosis, are reliable and have a similar small error range. The Cobb method 4 shows the best overall reliability. However, the centroid method and Cobb method using a fractured endplate do not produce an accurate result due to inter and intraobserver differences in determining the baseline.

• Restorative Dentistry and Endodontics
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• v.40 no.1
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• pp.58-67
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• 2015

Objectives: This study aimed to compare the accuracy of conventional intraoral (CI) radiography, photostimulable phosphor (PSP) radiography, cone beam computed tomography (CBCT) and multidetector computed tomography (MDCT) for detection of strip and root perforations in endodontically treated teeth. Materials and Methods: Mesial and distal roots of 72 recently extracted molar were endodontically prepared. Perforations were created in 0.2, 0.3, or 0.4 mm diameter around the furcation of 48 roots (strip perforation) and at the external surface of 48 roots (root perforation); 48 roots were not perforated (control group). After root obturation, intraoral radiography, CBCT and MDCT were taken. Discontinuity in the root structure was interpreted as perforation. Two observers examined the images. Data were analyzed using Stata software and Chi-square test. Results: The sensitivity and specificity of CI, PSP, CBCT and MDCT in detection of strip perforations were 81.25% and 93.75%, 85.42% and 91.67%, 97.92% and 85.42%, and 72.92% and 87.50%, respectively. For diagnosis of root perforation, the sensitivity and specificity were 87.50% and 93.75%, 89.58% and 91.67%, 97.92% and 85.42%, and 81.25% and 87.50%, respectively. For detection of strip perforation, the difference between CBCT and all other methods including CI, PSP and MDCT was significant (p < 0.05). For detection of root perforation, only the difference between CBCT and MDCT was significant, and for all the other methods no statistically significant difference was observed. Conclusions: If it is not possible to diagnose the root perforations by periapical radiographs, CBCT is the best radiographic technique while MDCT is not recommended.