• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.472-482
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• 2019

This paper describes the stabilization of underwater TAS winch system Deploy/Recover operation performance. TAS winch installed on the stern of submarine performs to deploy/recover sensor, towing cable and rope tail which is deployed from the stern and separated from submarine itself. Also TAS winch provides transmission path of power to the sensor and data transmitting/receiving path which data are acquired from underwater environment like sound, depth and temperature. At the step of TAS winch evaluation test, sporadic standstill and rotating speed oscillation phenomenon were occurred. Winch motor provides the available torque to deploy/recover TAS and root cause analysis to the winch motor was done to find exact reason to sporadic malfunction. When winch motor was disassembled, eccentricity of rotor, slip-ring and the other composition part for winch motor were found. These might cause magnetic field distortion. To make TAS winch system more stable and block magnetic field distortion, this paper suggests methods to enhance fixing status installed in winch motor. For reliable data acquisition for TAS winch operation, the deploy/recover function of the improved type of TAS winch was verified in LBTS making similar condition with sea status. At the end of stage, improved type of TAS winch was tested on some functions not only deploy/recover function, but sustainability of TAS operation on specific velocity, steering angle of submarine in the sea trial. Improved type of TAS winch was verified in accordance with design requirement. Also, validity of suggested methods were verified by the sea trial.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.3
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• pp.95-105
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• 2019

In recent years, image processing techniques for detecting road surface damaged spot have been actively researched. Especially, it is mainly used to acquire images through a smart phone or a black box that can be mounted in a vehicle and recognize the road surface damaged region in the image using several algorithms. In addition, in conjunction with the GPS module, the exact damaged location can be obtained. The most important technology is image processing algorithm. Recently, algorithms based on artificial intelligence have been attracting attention as research topics. In this paper, we will also discuss artificial intelligence image processing algorithms. Among them, an object detection method based on an region-based convolution neural networks method is used. To improve the recognition performance of road surface damage objects, 600 road surface damaged images and 1500 general road driving images are added to the learning database. Also, supervised learning using background object recognition method is performed to reduce false alarm and missing rate in road surface damage detection. As a result, we introduce a new method that improves the recognition performance of the algorithm to 8.66% based on average value of mAP through the same test database.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.643-650
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• 2021

The purpose of this study was to evaluate the impact of lecture content on the overall academic satisfaction in non-contact online classes. The study was conducted using an online survey of 107 university students attending metropolitan, local and foreign universities for a week from August 25th, 2020 to September 2nd, 2020. The analysis methods used included descriptive statistics and chi-square distribution, Fisher's exact test, linear by linear association, and logistic regression. The result of the study showed a significant decrease in Junior by 0.025 times compared to Senior (p<.05). Furthermore, a significant decrease in the impact of recorded lectures by 0.036 times compared to a hybrid of face-to-face and online lectures (p<.05). Compared to the response 'No', the number of student's responses of 'Yes' increased significantly by 31.358 times (p<.05). Additionally, a significant increase was seen in teaching methods by 19.709 times, and academic satisfaction by 7.989 times(p<.05). In conclusion, the results imply that the quality of lecture content is also important to improve the student's satisfaction with school life, but overall management is required in the areas of appropriate teaching methods, appropriate tuition, and evaluation methods.

• Journal of Korea Society of Industrial Information Systems
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• v.26 no.4
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• pp.19-32
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• 2021

It is well known that any maintenance works for aircrafts must be carried out strictly in accordance with the specified maintenance manuals, especially for military airplanes. According to our previous studies, the largest portion of the maintenance jobs for military aircrafts is found to be related to the assembly/disassembly of various parts, which requires precise understanding of the work procedures as well as correlation between interconnected parts let alone grasping of the exact shapes of parts involved. However, the conventional manuals for aircraft maintenance have failed to provide enough information required for the efficient maintenance except for simple texts and vague pictures, which are far from being sufficient sets of information. On the contrary, unlike incomplete conventional manuals with poor contents, 3D modeling SW could provide us with not only powerful visualization tool even to see through inside any assembly but also freedom to watch parts under test from any angle we want. In addition, the maintenance personnels could learn the precise maintenance procedures through repeatedly watching 3D animated version of the maintenance work as if they were on the field. In this study, we have suggested the efficient procedures to develop 3D manual for aircraft maintenance using 3D modeling SW, Solidworks and implemented a 3D maintenance manual for Integrated Drive Generator(IDG) in Boeing 747. Characteristics of the developed 3D manual has been analyzed in comparison with the conventional ones as well. It is shown that the suggested method could be easily applied to develop a 3D maintenance manual for commercial airplanes since the maintenance works involving assembly/disassembly of major parts are very similar regardless of aircraft types.

• Journal of the Korean Geotechnical Society
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• v.22 no.12
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• pp.5-14
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• 2006

In general, the dredged ground was composed of a big difference of sediment shape through segregating sedimentary of finer soil in case of reclaiming by dredged coarse soils. Therefore, this study was performed to evaluate the change of settling velocity of flow, and the density of sedimentary which is based on settling tests and self-weight consolidation tests, and consolidation test by seepage force according to the percentage of coarse of Kunsan dredge soils. The Yano's method has been applied to estimate the settlement of self-weight consolidation in finer soils at design but it only considers pouring water content and elevation of interface, therefore the other method needs to be introduced for the exact prediction of the settlement of coarse soil in which the segregation sedimentation is occurring. In this study, the settlement of self-weight consolidation was calculated by the change of the density of segregating sedimentary of coarse and finer soils which was analyzed by Yano's method to extend a serious of researches. The self-weight consolidation by Yano's method will not reflect the segregated settling in dredging coarse soil under 40% of #200 passing percentage. As a result, the evaluation technique of settlement of self-weight consolidation considering a change of the density of segregating sedimentary is suggested as a reasonable method that considers the sediment shape of coarse soil.

• The Journal of the Society of Stroke on Korean Medicine
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• v.13 no.1
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• pp.43-51
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• 2012

Object : The purpose of this study was to evaluate the relationship between pattern identification (PI) and stroke risk factors, such as hypertension, diabetes mellitus, dyslipidemia, stroke history, obesity, abdominal obesity and metabolic syndrome. Methods : 46 patients with acute ischemic stroke were recruited from May 2012 to November, 2012. We analyzed the data of 32 patients, and pattern identification was identified by resident and specialist of Korean medicine. We analized patient's PI and risk factor by Fisher's exact test. Results : We found that Dampness-phlegm group was more related with patient's metabolic syndrome than non Dampness-Phlegm group. And Yin deficiency group had less relationship with patient's metabolic syndrome, obesity, abdominal obesity and dyslipidemia than non Yin deficiency group. Conclusions : According to the analysis, these results provide evidence for relationship between the Dampness-phlegm group, Yin deficiency and metabolic syndrome.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.62-68
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• 2016

Purpose In a cyclosporine experiment using a robotic liquid handing system has found a deviation of its standard curve and low reproducibility of patients's results. The difference of the test is that methanol is mixed with samples and the extractions are used for the test. Therefore, we assumed that the abnormal test results came from using methanol and conducted this test. In a manual of a robotic liquid handling system mentions that we can choose several setting parameters depending on the viscosity of the liquids being used, the size of the sampling tips and the motor speeds that you elect to use but there's no exact order. This study was undertaken to confirm pipetting ability depending on types of liquids and investigate proper setting parameters for the optimum dispensing ability. Materials and Methods 4types of liquids(water, serum, methanol, PEG 6000(25%)) and $TSH^{125}I$ tracer(515 kBq) are used to confirm pipetting ability. 29 specimens for Cyclosporine test are used to compare results. Prepare 8 plastic tubes for each of the liquids and with multi pipette $400{\mu}l$ of each liquid is dispensed to 8 tubes and $100{\mu}l$ of $TSH^{125}I$ tracer are dispensed to all of the tubes. From the prepared samples, $100{\mu}l$ of liquids are dispensed using a robotic liquid handing system, counted and calculated its CV(%) depending on types of liquids. And then by adjusting several setting parameters(air gap, dispense time, delay time) the change of the CV(%)are calcutated and finds optimum setting parameters. 29 specimens are tested with 3 methods. The first(A) is manual method and the second(B) is used robotic liquid handling system with existing parameters. The third(C) is used robotic liquid handling system with adjusted parameters. Pipetting ability depending on types of liquids is assessed with CV(%). On the basis of (A), patients's test results are compared (A)and(B), (A)and(C) and they are assessed with %RE(%Relative error) and %Diff(%Difference). Results The CV(%) of the CPM depending on liquid types were water 0.88, serum 0.95, methanol 10.22 and PEG 0.68. As expected dispensing of methanol using a liquid handling system was the problem and others were good. The methanol's dispensing were conducted by adjusting several setting parameters. When transport air gap 0 was adjusted to 2 and 5, CV(%) were 20.16, 12.54 and when system air gap 0 was adjusted to 2 and 5, CV(%) were 8.94, 1.36. When adjusted to system air gap 2, transport air gap 2 was 12.96 and adjusted to system air gap 5, Transport air gap 5 was 1.33. When dispense speed was adjusted 300 to 100, CV(%) was 13.32 and when dispense delay was adjusted 200 to 100 was 13.55. When compared (B) to (A), the result increased 99.44% and %RE was 93.59%. When compared (C-system air gap was adjusted 0 to 5) to (A), the result increased 6.75% and %RE was 5.10%. Conclusion Adjusting speed and delay time of aspiration and dispense was meaningless but changing system air gap was effective. By adjusting several parameters proper value was found and it affected the practical result of the experiment. To optimize the system active efforts are needed through the test and in case of dispensing new types of liquids proper test is required to check the liquid is suitable for using the equipment.

• The Journal of Korean Society for School & Community Health Education
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• v.9 no.1
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• pp.85-97
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• 2008

Objectives: This study was designed to understand the oral health knowledge & conduct of middle-school students, search for the learning objective and the educational method in line with the subjects and of utilizing as the basic data for an effective oral health-care program. Methods: The samples to achieve the purpose of this research are composed of 139 students in middle-school, OO county. Chungcheongbuk-do, the number of male students 64, and female students 75. Data were statistically analyzed by frequency analysis, $x^2$-test or Fisher's exact test by using SPSS WIN Ver. 12.0. Results: Among items on oral-health knowledge in middle-school students. the awareness ratio on a cause and preventive method for oral disease was surveyed to be lower than the awareness ratio on symptoms of oral disease. As a result of examining by comparing knowledge and behavior on the time of tooth brush. both awareness and behavior were the level of 50% or less than it. In particular, 46.2% perceived after lunch. but practice just accounted for 33.0%. The frequency of tooth brush a day was the largest in a case(47.5%) of doing twice a day. However. there was also the response (5.8%) with saying of brushing once or not brushing even once. Thus, the practice of tooth brush was surveyed to be very low even if being a minority of students. The frequency of taking a light meal was 68.8% in less than twice a day. However, even students of taking more than five times were surveyed to be 9.8%. Out of the whole-body health in over 50%-59.9%. the oral health was surveyed to be perceived to be very important. Compared to the awareness level on importance of a tooth, the ratio of visiting a dentistry was analyzed to be very low. Conclusions: The study results suggest that the school oral-health project was examined to have the necessity of being expanded and carried out even in middle-and-high schools, by which the specific oral-health promotion program including oral-health education in this period is developed.

• Journal of dental hygiene science
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• v.8 no.3
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• pp.123-129
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• 2008

The purpose of this study was to investigate the actual conditions of the subjective oral malodor perception of the survey subjects. Through the subjective questionnaire method over about 3 months from June to August in 2007, the data was collected targeting 275 adults. Statistical methods used were Chi-square test, Fisher's exact test and One-way ANOVA. And, the following results were obtained. 1. When having seen the ratio of those who were conscious of oral malodor, the adults, who responded with saying of feeling oral malodor at present and at ordinary times, accounted for 68.4% and 79.3%, respectively. And, the adults, who responded with saying of not feeling, were indicated to be 31.6%(at present) and 20.7%(at ordinary times), respectively. 2. Almost 83.5% of total people answered that they had most severe oral malodor at the time of awakening and 51.9% of subjects answered tongue contributed to the their oral malodor. 3. About the type of oral malodor, although 37.2% of the group thought the type of oral malodor was a food smell and fetid smell was second general burning smell occurred the time of hunger(22.5%). 4. In the answers of hoping for treatment of oral malodor, 66.9% of the people showed positive response to dental treatment for controlling their oral malodor. Especially 7.3% of subjects showed very big desire for treatment. 5. In the level of oral malodor that is felt now according to the time of a meal, the case of within 1 hour after having a meal was responded to be not felt the oral malodor with 44.7%. And, there was response with saying of not feeling oral malodor in 37.6% as for 1-2 hours, 16.3% as for 2-3 hours, 14.8% as for 3-4 hours, and 23.7% as for more than 4 hours. Thus, the level of oral malodor according to the time of a meal showed the statistically significant difference(p<0.01). Through the results of this study, it could be known about whether or not being conscious of oral malodor in general people, the main cause and region for oral malodor, the importance and practicing method of tongue brush through literature. Accordingly, there is necessity of further researching and comparing whether or not being conscious of oral malodor by diversely surveying relevancy with factors of causing oral malodor based on the objective oral malodor measurement value. The future diverse researches are thought to be necessarily performed in order to prevent or reduce oral malodor.

• Childhood Kidney Diseases
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• v.13 no.1
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• pp.49-55
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• 2009

Purpose : We aimed to compare the frequency of positive repeat urine cultures 48 hours after antimicrobial treatment between anatomically normal and abnormal urinary tract Infection (UTI) groups to determine the potential clinical usefulness of the tests. Methods : We reviewed medical records of 930 patients under age 14, who had been admitted for UTI at Gyeongsang National University Hospital from January 1, 1998 to August 1, 2008. The eligible patients were divided into two groups the anatomically normal UTI group and the anatomically abnormal UTI group. Statistical analyses were performed with variables consisting of the sex ratio, age distribution and the frequency of positive repeat urine cultures of each group. Results : The sex ratio of the anatomically normal UTI group was M:F=1.9:1, whereas that of the anatomically abnormal UTI group was M:F=3.5:1 (P=0.019). For age distribution, it was found that the mean age of the anatomically normal UTI group was $0.82{\pm}1.83$ years, whereas that of the anatomically abnormal UTI group was $1.18{\pm}2.57$ years (P=0.113). The frequency of positive repeat urine cultures in the anatomically normal UTI group was 3/279 (1.1%), whereas that of the anatomically abnormal UTI group was 1/90 (1.1%) (P=0.675). Conclusion : We conclude that performing a repeat urine culture is not justified in terms of clinical usefulness, and it is unreasonable to use the results as an index of therapeutic success. A follow-up urine culture is unnecessary in patients with both the anatomically normal and abnormal UTI group.