• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.153-161
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• 2020

Due to the recent development of the 4th industrial revolution, Smart Factories that organically link various technologies such as AI, IoT, Cloud, and Big Data are increasing. Based on this, in the industrial environment where the internal process is controlled automatically, high availability should be secured against the loss caused when the internal process of the Smart Factory is stopped due to the determinism and malicious attack necessary to control the device such as PLC. The research and analysis of industrial network equipment and security equipment used in various industries can improve the efficiency and usability of industrial control systems in national infrastructure and can provide important feedback to build related infrastructure. Therefore, we compared industrial network equipment and security equipment in this paper in a variety of ways and expect to be used as a roadmap for developing technologies for industrial network equipment and industrial security equipment based on the results of this paper.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.413-422
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• 2015

This study is conducted for the purpose of conceptualizing a choral communication model. first, the musical communication models analyzed to know how it can apply in the choral music. As a result, we take the music communication is the interaction between composers, performers and audience. But the choral music have properties not found in the general music. The choral music is the need for internal communication process before performing music. First, the conductor is to interpret the music. Next, choral members are shared the interpretation of music. This internal communication be conducted properly, musical communication with the audience will be successful. The trial model provided for in this study will be a guideline for successful communication in the choral music, theoretically or practically.

• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.186-193
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• 2008

The Internet's low cost and ubiquity present an attractive option for real-time distributed control of processes on the factory floor. When integrated with the Internet, the LonWorks open control network can give ubiquitous accessibility with the distributed control nature of information on the factory floor. One of the most important points in real-time distributed control of processes is timely response. There are many processes on the factory floor that require timely response. However, the uncertain time delay inherent in the network makes it difficult to guarantee timely response in many cases. Especially, the transmission characteristics of the LonWorks/IP network show a highly stochastic nature. Therefore, the time delay problem has to be resolved to achieve high performance and quality of the real-time distributed control of the process in the LonWorks/IP Virtual Device Network (VDN). It should be properly predicted and compensated. In this paper, a new distributed control scheme that can compensate for the effects of the time delay in the network is proposed. It is based on the PID controller augmented with the Smith predictor and disturbance observer. Designing methods for output feedback filter and disturbance observer are also proposed. Tracking position control experiment of a geared DC Servo motor is performed using the proposed control method. The performance of the proposed controller is compared with that of the Internal Model Controller (IMC) with the Smith predictor. The result shows that the performance is improved and guaranteed by augmenting a PID controller with both the Smith predictor and disturbance observer under the stochastic time delay in the LonWorks/IP VDN.

• Journal of Korean Medical Science
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• v.33 no.52
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• pp.339.1-339.11
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• 2018

Background: Hip pain is a common musculoskeletal complaint in general practice. Although comprehensive diagnostic approach on hip pain is mandatory for adequate treatment, un- or mis-diagnosis is not rare in primary care. The aim of this study was to analyze descriptively un- or mis-diagnosed hip pain cases referred from primary care to a tertiary hospital, especially in young adults ${\leq}50years\;old$. Methods: We retrospectively analyzed a consecutive cohort of 150 patients (${\leq}50years\;old$) with chronic hip pain (${\geq}6weeks$), which was not diagnosed or misdiagnosed based on the information provided on the referral form. Results: Overall an average 32 cases/month were referred due to hip pain without a diagnosis or with an incorrect diagnosis. Among them, 150 patients were enrolled in this study and 146 (97.3%) could be allocated to a specific disease by using data from routine clinical practice. Four common final diagnoses were femoroacetabular impingement (FAI) syndrome (55.3%), hip dysplasia (HD, 13.3%), referred pain from the lumbar spine (9.3%), and spondyloarthritis (SpA, 7.3%). In patients with FAI syndrome, 37 (44.0%) had pincer-type FAI and 33 (39.8%) had combined-type. Although the pain site or gender was not tightly clustered, the distribution of final diagnosis was significantly different according to hip pain location or gender. Especially, SpA or HD was not observed in younger women subgroup or elder men subgroup, respectively, when stratified by the mean age of participants. Conclusion: Most (> 80%) young patients with hip pain, a difficult issue to diagnosis for many primary physicians, had FAI syndrome, HD, spine lesions, and SpA. This study could give a chance to feedback information about cases with un- or mis-diagnosed hip pain, and it suggests that primary physicians need to be familiar with the diagnostic approach for these 4 diseases.

• Korean Medical Education Review
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• v.23 no.3
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• pp.185-193
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• 2021

Students must be familiar with clinical skills before starting clinical practice to ensure patients' safety and enable efficient learning. However, performance is mainly tested in the third or fourth years of medical school, and studies using the validity framework have not been reported in Korea. We analyzed the validity of a performance test conducted among second-year students classified into content, response process, internal structure, relationships with other variables, and consequences according to Messick's framework. As results of the analysis, content validity was secured by developing cases according to a pre-determined blueprint. The quality of the response process was controlled by training and calibrating raters. The internal structure showed that (1) reliability by generalizability theory was acceptable (coefficients of 0.724 and 0.786, respectively, for day 1 and day 2), and (2) the relevant domains had proper correlations, while the clinical performance examination (CPX) and objective structured clinical examination (OSCE) showed weaker relationships. OSCE/CPX scores were correlated with other variables, especially grade point average and oral structured exam scores. The consequences of this assessment were (1) making students learn clinical skills and study themselves, while causing too much stress for students due to lack of motivation; (2) reminding educators of the need to apply practical teaching methods and to give feedback on the test results; and (3) providing an opportunity for faculty to consider developing support programs. It is necessary to develop the blueprint more precisely according to students' level and to verify the validity of the response process with statistical methods.

• Progress in Medical Physics
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• v.23 no.2
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• pp.91-98
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• 2012

Verification of internal organ motion during treatment and its feedback is essential to accurate dose delivery to the moving target. We developed an offline based internal organ motion verification system (IMVS) using cine EPID images and evaluated its accuracy and availability through phantom study. For verification of organ motion using live cine EPID images, a pattern matching algorithm using an internal surrogate, which is very distinguishable and represents organ motion in the treatment field, like diaphragm, was employed in the self-developed analysis software. For the system performance test, we developed a linear motion phantom, which consists of a human body shaped phantom with a fake tumor in the lung, linear motion cart, and control software. The phantom was operated with a motion of 2 cm at 4 sec per cycle and cine EPID images were obtained at a rate of 3.3 and 6.6 frames per sec (2 MU/frame) with $1,024{\times}768$ pixel counts in a linear accelerator (10 MVX). Organ motion of the target was tracked using self-developed analysis software. Results were compared with planned data of the motion phantom and data from the video image based tracking system (RPM, Varian, USA) using an external surrogate in order to evaluate its accuracy. For quantitative analysis, we analyzed correlation between two data sets in terms of average cycle (peak to peak), amplitude, and pattern (RMS, root mean square) of motion. Averages for the cycle of motion from IMVS and RPM system were $3.98{\pm}0.11$ (IMVS 3.3 fps), $4.005{\pm}0.001$ (IMVS 6.6 fps), and $3.95{\pm}0.02$ (RPM), respectively, and showed good agreement on real value (4 sec/cycle). Average of the amplitude of motion tracked by our system showed $1.85{\pm}0.02$ cm (3.3 fps) and $1.94{\pm}0.02$ cm (6.6 fps) as showed a slightly different value, 0.15 (7.5% error) and 0.06 (3% error) cm, respectively, compared with the actual value (2 cm), due to time resolution for image acquisition. In analysis of pattern of motion, the value of the RMS from the cine EPID image in 3.3 fps (0.1044) grew slightly compared with data from 6.6 fps (0.0480). The organ motion verification system using sequential cine EPID images with an internal surrogate showed good representation of its motion within 3% error in a preliminary phantom study. The system can be implemented for clinical purposes, which include organ motion verification during treatment, compared with 4D treatment planning data, and its feedback for accurate dose delivery to the moving target.

• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.398-413
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• 2016

This work describes the design and development of a new drying system for a rollover carwash machine with the support of numerical tools. The drying system is composed of a pair of stationary vertical dryers and a moveable horizontal dryer that can adjust itself to the contour of a vehicle. After the definition of the dryers' concept, their performance was assessed individually to check their internal flow pattern and to improve their airflow distribution. These issues are expected to provide feedback on redesign and geometric optimization of the dryers. After redesign of the dryers separately, the behaviour of the complete drying system was studied on actual vehicle models, representative of the shortest and tallest dimensions that can be washed with the existing carwash machine sector. The drying efficiency of the whole system was studied by calculation of shear stress distribution on various surfaces of a given vehicle. The results allowed concluding that the overall drying performance of the design system is very good and assure adequate drying on most vehicles surfaces. The results obtained from numerical studies were then validated with experimental measurements and a good agreement was found between the two. The procedure employed in this work can be applied to support the design and analysis of other mechanical drying systems.

• Journal of Families and Better Life
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• v.26 no.1
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• pp.137-147
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• 2008

This study aimed to explore the plausible application of Coaching in the major of family resource management. For this purpose, first, this study reviewed the historical background of the coaching. In the contents, the concepts and principles of coaching were identified. Second, The recent application of coaching to the various areas such as finns, centers, occupation and the academical fields in Korea as well other countries were investigated. Finally, this study connected the nature and emphasis of the family resource management with the philosophy of coaching, which focuses on the internal strength of his/their own change and development in an/a individual/organization. Also, the process of family resource management and coaching models which were regarded as the similar ones in the phases consisted of situation perception, exploring alternatives, planning, implementing and feedback. On the basis of these contexts, this study suggested the plausible classes applied coaching which are able to be introduced in the under-graduated and graduated courses.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.651-657
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• 2012

In many control fields high position performance is essentially required in reducing the over-shoot phenomena which is produced by improving the quick response in starting and in minimizing the variation of the response characteristic on disturbance and load variation In this paper, the design method for a position control is suggested for constructing the PI-PD controllers by using an internal PD feedback loop in PI and PD control system. Applying this method to the position control system used a DC servo motor as a driver, the transfer PI and PD controllers are designed simultaneously and the coefficients of these controllers are determined by using the transfer function of a plant and a proportional coefficient from mathematical technique. From the result of computer simulation in PI-PD control system by applying this control technique, we can verify the usefulness of this method in rejecting of over-shoot of starting, compensating of response variation on the load variation, and shorting the settling time.

• International Journal of Aeronautical and Space Sciences
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• v.10 no.1
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• pp.91-97
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• 2009

It is undertaken systematization of results of satellite and ground observation parameters characterizing a current condition and climatic variability of two selected geographical areas. One of them covers territory of Azerbaijan and another covers a wide area of Caspian See region. Average values and mean square deviations of following values are investigated: outgoing long wave radiation during a day and night (in nebulosity and cloudless). absorbed within a day of the stream of a sunlight of the system in "a terrestrial surface-atmosphere". degree of a covering by clouds of the selected areas during a day and at night, ground temperature values of air. pressure and speed of a wind. Monthly average values of corresponding parameters create a basis of suggested investigations. It has been presented features of a time course of investigated parameters for each month and year in the whole due to the continuously observations since 1982-2000. The scientific problem consists that there are no existed models which authentically would be cover the main aspects of a realities specified changes: they are identified by economic activities. growth of the population and other features of development of a human society or internal fluctuations of biogeophysical/climatic system. Possibilities of predictability of biosphere and climate changes depend on available timely supervision. adequacy of construction of appropriate models. understanding of mechanisms of direct and feedback influences in such complicated systems.