• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.2
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• pp.125-132
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• 2003

This study introduces a simulation model of radar responses from subsurface voids in concrete for their frequency variations. In this model, resolution and attenuation characteristics due to frequency variations are analyzed at each material interface which has different electromagnetic property. This model aims at the selection of best frequency of radar which can analyze the thickness of voids in concrete from radar responses. It can also be applied to estimate the limitation of propagation depth of radar on subsurface voids in concrete. The computed results show the radar images obtained by using a radar signal processing technique using convolution.

• Journal of Internet Computing and Services
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• v.6 no.2
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• pp.25-35
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• 2005

The Rate Monotonic(RM) scheduling algorithm and Earliest Deadline First(EDF) scheduling algorithm are normally used in Real-Time scheduling algorithm. In those scheduling algorithm, we could predict the performance possibility with total utilization value of task group. But. it had problems with prediction of the boundedness in individual task when the utilization value was over in temporary task. In this paper, the suggested scheduling algorithm can predict task when the utilization value was over and it suggested the method of predicting scheduling possibility based on the utilization value of individual task as well. it predicted the boundedness of scheduling possibility test through simulation In Real-Time scheduling algorithm and analyzed the result.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1457-1465
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• 2009

This study was conducted to analyze the food safety management practices and to provide data that could be used to improve food safety management at kindergarten foodservice establishments in Daegu and Gyeongbuk province. Microbiological hazard analysis was conducted from May to July, 2008 at the four foodservice establishments. A total (20 items) of foodservice facilities, cooking utensils, and equipment were tested about total plate counts, coliforms, E. coli, Staphylococcus aureus, Salmonella spp., and Listeria monocytogenes. The microbiological detected levels were higher than the critical limits for prepreparing and cooking knives, chopping boards, working tables (both prepreparing and cooking), refrigerator (inside wall), bart, basket, and tray. E. coli, Salmonella spp., and Listeria monocytogens were not detected in any samples. However, Staphylococcus aureus were detected in rubber gloves for cooking and trench in the bottom at one foodservice establishment. In conclusion, these results suggest that a prerequisite programs guideline should be provided to improve the food safety levels at kindergarten foodservice establishments and the foodservice manager must maintain proper food safety technique for foodservice facilities, cooking utensils, and equipment at kindergarten foodservice establishments to prevent cross-contamination and spread of foodborne pathogens.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.1
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• pp.68-72
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• 2015

Ultrasonic inspection robot systems have been widely researched and developed for the real-time monitoring of structures such as power plants. However, an inspection robot that is operated in a simple pattern has limitations in its application to various structures in a plant facility because of the diverse and complicated shapes of the inspection objects. Therefore, accurate control of the robot is required to inspect complicated objects with high-precision results. This paper presents the idea that the shape and movement information of an ultrasonic inspector's hand could be profitably utilized for the accurate control of robot. In this study, a polymer flex sensor was applied to monitor the shape of a human hand. This application was designed to intuitively control an ultrasonic inspection robot. The movement and shape of the hand were estimated by applying multiple sensors. Moreover, it was successfully shown that a test robot could be intuitively controlled based on the shape of a human hand estimated using polymer flex sensors.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.1
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• pp.12-17
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• 2006

A steam generator of nuclear power plant has thousands of thin tubes. These tubes play an important role in maintaining the pressure boundary between the primary and secondary side of nuclear power plant. The steam generator tube is easy to be damaged because of the severe operating conditions such as the high temperature and pressure. Therefore, tremendous efforts are made to assess the structural integrity of the steam generator tubes. The eddy current test is the most popular non-destructive test to assess the integrity of the tubes. However, the eddy current test has the limitation to size the flaw accurately because the eddy current signal behavior depends on the total volume of flaw. This paper shows the possibility that the ultrasonic test method can be applied to detect the flaws in the steam generator tubes and to measure them quantitatively. From the test results, it is expected that if the ultrasonic test is put to practical use in the steam generator tube inspection, the inspection results will be improved.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.297-304
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• 2014

The present study was designed to investigate the effect of home based exercise program on balance recovery of stroke patients. In total, 20 participants were assigned to a control group(n=10) or exercise group(n=10) between September 2013 and December 2013. In addition to existing physiotherapy, the exercise group received home based exercise program consisting of weight transfer, training endurance, mobility, sensory retraining, lower limb exercise for 30 minutes, 2 times a week, for 8 weeks, every time for 30 minutes. Balance ability was assessed by measuring foot pressure(FP), limit of stability(LOS) and velocity sway(VS) by using Biorescue and by using the functional reaching test(FRT). To compare the improvement level of each group's balance ability, examination of independent sample T was done. Significant differences between control group and exercise group in LOS, VS of affect side and FRT were observed. This study showed that home based exercise program application was effective strategy on balance recovery in a post stroke population.

• Journal of the Korean Society of Radiology
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• v.84 no.1
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• pp.3-14
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• 2023

Breast Imaging Reporting and Data System (BI-RADS) is a communication and data tracking system that standardizes and controls the quality of reporting by presenting lexicon descriptors, assessment categories, and recommendations for managing breast lesions. Using standardized terminology recommended by BI-RADS, radiologists can concisely and reproducibly communicate breast imaging results to clinicians. They can also provide the estimated malignant probability of the lesions found and guide management for them by determining the final assessment category. The limitations of BI-RADS 5th edition currently in use are that there are some areas for which standardized terminologies still need to be established, and that the diagnostic criteria of MRI assessment categories 3 and 4 are ambiguous compared to those for mammography or ultrasound. The next revision of BI-RADS is expected to include solutions for overcoming current limitations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.6B
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• pp.630-640
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• 2009

The thesis suggests hand-held equipment to overhaul for mobile TFT LCD/OLED module of high-performance. The established module equipment to overhaul could distinguish outputting video data to module for distinguishing flicker, but it is impossible with low system. In this thesis, supporting system could check the various supplement functions from bringing equipment to overhaul without changing design of FPGA or H/W the module various size for equipment to overhaul for module of high-performance coincidently. The system includes hand-held equipment to overhaul, test software embedded and software a base personal computer and have designed to output, save, and certify all contents of module test of hand-held equipment to overhaul to interface universal serial bus. Setting up 9 items that represent for efficient verification of the proposed system have been possible confirmation with TFT LCD/OLED module of high-performance, establishment scan time, creation gamma, changing register, supporting interface, and multi inch modules.

• 한국노년학
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• v.40 no.2
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• pp.325-340
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• 2020

Early diagnosis and intervention of dementia is critical to minimize future risk and cost for patients and their families. The purpose of this study was to develop and validate Figure-Copy Test(FCT), as a new dementia screening test, that can measure neurological damage and cognitive impairment, and then to examine whether the grading precesses for screening can be automated through machine learning procedure by using FCT imag es. For this end, FCT, Korean version of MMSE for Dementia Screening (MMSE-DS) and Clock Drawing Test were administrated to a total of 270 participants from normal and damaged elderly groups. Results demonstrated that FCT scores showed high internal constancy and significant correlation coefficients with the other two test scores. Discriminant analyses showed that the accuracy of classification for the normal and damag ed g roups using FCT were 90.8% and 77.1%, respectively, and these were relatively higher than the other two tests. Importantly, we identified that the participants whose MMSE-DS scores were higher than the cutoff but showed lower scores in FCT were successfully screened out through clinical diagnosis. Finally, machine learning using the FCT image data showed an accuracy of 73.70%. In conclusion, our results suggest that FCT, a newly developed drawing test, can be easily implemented for efficient dementia screening.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.103-107
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• 2000

Traditionally, EPT and thermal tests were used as diagnostic methods for pulp vitality test. The thermal and electrical stimulation tests are the methods to determine the vitality of a tooth based on its neuronal response. These have certain limitations, one of them is the difficulty of approaching the correct result in case of treatment of children. The reason is management problem caused by the unpleasant stimulation. Also, the response from patients are not objective, and false positive or false negative could be happened. Recently, laser doppler flowmetry and pulse oximeter which evaluate vascular integrity are introduced in an effort of overcoming to limitation of traditional methods. The principle of pulse oximeter is to and out level of oxygen saturation by ratio of the two pulses between emitted light and detected light penetrating them to the termination of body, such as ears or fingers. From this point of view, it can be applied to a tooth to determine its vitality. The objective of this study lies mainly on varifying pulse oximeter as a method of determining tooth vitality and providing basic data of its clinical implementation. The result of the research showed that level of oxygen saturation in vital teeth was average of 96.3% and 0.0% in pulpless teeth. As a comprehensive result, pulse oximeter could be an useful diagnostic equipment in determining of tooth vitality.