• Journal of Korean Society for Quality Management
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• v.15 no.2
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• pp.10-19
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• 1987

Statistical control charts are useful tools to monitor and control the manufacturing processes and are widely used in most Korean industries. Many Korean companies, however, do not always obtain desired results from the traditional control charts by Shewhart such as the $\overline{X}$-chart, X-chart, $\widetilde{X}$-chart, etc. This is partly because the quality charterstics of the process are not distributed normally but are skewed due to the intermittent production, small lot size, etc. In the Shewhart $\overline{X}$-chart, which is the most widely used one in Korea, such skewed distributions make the plots to be inclined below or above the central line or outside the control limits although no assignable causes can be found. To overcome such shortcomings in nonnormally distributed processes, a distribution-free type of confidence interval can be used, which should be based on order statistics. This thesis is concerned with the design of control chart based on a sample median which is easy to use in practical situation and therefore properties for nonnormal distributions may be easily analyzed. Control limits and central lines are given for the more famous nonnormal distributions, such as Gamma, Beta, Lognormal, Weibull, Pareto, and Truncated-normal distributions.

• Nuclear Engineering and Technology
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• v.40 no.1
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• pp.69-76
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• 2008

Most pressurized water reactors use Venturi flow meters to measure the feedwater flow rate. However, fouling phenomena, which allow corrosion products to accumulate and increase the differential pressure across the Venturi flow meter, can result in an overestimation of the flow rate. In this study, a soft-sensing model based on fuzzy support vector regression was developed to enable accurate on-line prediction of the feedwater flow rate. The available data was divided into two groups by fuzzy c means clustering in order to reduce the training time. The data for training the soft-sensing model was selected from each data group with the aid of a subtractive clustering scheme because informative data increases the learning effect. The proposed soft-sensing model was confirmed with the real plant data of Yonggwang Nuclear Power Plant Unit 3. The root mean square error and relative maximum error of the model were quite small. Hence, this model can be used to validate and monitor existing hardware feedwater flow meters.

• The Journal of Korean Physical Therapy
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• v.33 no.1
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• pp.16-20
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• 2021

Purpose: This study examined the effects of the type of video contents used for action observations on the ability to control posture. Methods: The participants were 48 healthy adults. The two hands of the participants were crossed on both shoulders, and the other foot was placed in a straight line in front of the target to allow them to watch a video of the monitor. The videos were presented in random order with three video contents (natural, stable balance posture, and unstable balance posture) consisting of 30 seconds each. A 15-second resting time was given between each video. During action observation using various video content forms, the posture control ability was measured using a TekScan MetScan^® system. Results: The results revealed statistically significant differences in the area of movement and the distance by COP and distance by the type of action-observation videos, and the distance by the anteroposterior and mediolateral sides (p<0.05). The stable balance posture and unstable balance posture video showed significant differences in the distance by the COP, anteroposterior, and mediolateral distance. (p<0.05) Conclusion: This study suggests that choosing the contents of the videos is important during action-observation training, and action-observation training can help improve postural control.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.1218-1221
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• 2011

The development of the internet and information management has enabled new applications which include: Electronic medical record (EMR), intelligent transportation, environmental monitoring, etc. In this paper, we design and implement the Continuity Care Record(CCR) Data Stream management server that compiled with DSMS and DBMS in EMR system for processing, monitoring the incoming CCR data stream and storing the processed result with high-efficiency. The proposed system enables users not only to query stored CCR information from DBMS, but also enables to execute continue query for the real-time CCR Data Stream. By using of CCR Viewer Application users can view or update their personal health records even compare self health care records with standard health care records in order to monitor the healthy status, and the on line updating information would be minimized and medical error.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.2
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• pp.41-49
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• 2024

This paper discusses the modeling and implementation of a worker location system at a shipbuilding site. The importance of worker location in an industrial environment is highlighted as a critical element in the prevention of industrial accidents. The paper presents a worker tracking system that integrates power line and beacon communication to accurately track worker position. Through experiments, the paper demonstrates how to monitor the changes in worker location based on different scenarios and how to access the status of worker location using the manager's web service. The paper can be used for the design of a system that will provide real-time location information to safety managers for the improvement of worker safety management.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.101-107
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• 2020

Road surface measurement is an essential process for quantifying the degree and displacement of roughness in road surface management. For safer road surface management and quick maintenance, it is important to accurately measure the road surface while mounted on a vehicle. In this paper, we propose a sophisticated road surface measurement system that can be measured on a moving vehicle. The proposed road surface measurement system supports more accurate measurement of the road surface by using a high-performance line laser sensor. It is also possible to measure the transverse and longitudinal profile by matching the position information acquired from the RTK, and the velocity adaptive update algorithm allows a manager to monitor in a real-time manner. In order to evaluate the proposed system, the Gocator laser sensor, MRP module, and NVIDIA Xavier processor were mounted on a test mobile and tested on the road surface. Our evaluation results demonstrate that our system measures accurate profile base on the MSE. Our proposed system can be used not only for evaluating the condition of roads but also for evaluating the impact of adjacent excavation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.556-560
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• 2002

In this paper, we propose a remote controller for robot manipulator using local area network(LAN) and internet. To do this, we develope a server-client system as used in the network field. The client system is in any computer in remote place for the user to log-in the server and manage the remote factory. the server system is a computer which controls the manipulator and waits for a access from client. The server system consists of several control algorithms which is needed to drive the manipulator and networking system to transfer images that shows states of the work place, and to receive a Tmp data to run the manipulator The client system consists of 3D(dimension) graphic user interface for teaching and off-line task like simulation, external hardware interface which makes it easier for the user to teach. Using this server-client system, the user who is on remote place can edit the work schedule of manipulator, then run the machine after it is transferred and monitor the results of the task.

• Asian Journal of Atmospheric Environment
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• v.10 no.1
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• pp.1-12
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• 2016

Numerous researchers have proposed that surface area is a more appropriate indicator than mass for evaluating pulmonary inflammatory responses caused by exposure to fine and ultrafine particles. In this study, measurements of surface area concentrations of aerosols were conducted in Yokohama, Japan, using the diffusion charging method. $PM_{2.5}$ mass concentration and black carbon concentration in $PM_{2.5}$ were also measured. The 24-hour continuous measurement campaigns were conducted 39 times from March to November, 2014. The surface area concentration was more closely correlated with the black carbon concentration than with the $PM_{2.5}$ mass concentration. It is considered that the abundance of black carbon particles significantly affects the surface area concentration of $PM_{2.5}$. The strength of the correlation between the surface area and black carbon concentrations varied considerably among the measurement campaigns. A relatively weaker afternoon correlation was observed compared with the other time zones (morning, evening, and night). We consider that these phenomena are due to the transportation/formation of the particles other than black carbon that affects surface area concentration and/or the variation of the surface condition of the black carbon particles.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.474-486
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• 2015

This paper proposes a multi-objective optimal placement method of Phasor Measurement Units (PMUs) in large electric transmission systems. It is proposed for minimizing the number of PMUs for complete system observability and maximizing measurement redundancy of the buses, simultaneously. The measurement redundancy of the bus indicates that number of times a bus is able to monitor more than once by PMUs set. A high level of measurement redundancy can maximize the system observability and it is required for a reliable power system state estimation. Therefore, simultaneous optimizations of the two conflicting objectives are performed using a binary coded firefly algorithm. The complete observability of the power system is first prepared and then, single line loss contingency condition is added to the main model. The practical measurement limitation of PMUs is also considered. The efficiency of the proposed method is validated on IEEE 14, 30, 57 and 118 bus test systems and a real and large- scale Polish 2383 bus system. The valuable approach of firefly algorithm is demonstrated in finding the optimal number of PMUs and their locations by comparing its performance with earlier works.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1150-1156
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• 2004

The GMO (Genetically Modified Organism) labeling system on raw materials has been in Korea since March 2001, and genetically modified organisms (GMOs)-derived foods since July 2001. Therefore, we designed a multiplex PCR method to ascertain the validity of the labeling system and to monitor the status of circulation for genetically modified maize (GM Maize). Five lines of GM Maize (GA21, TC1507, Mon810, NK603, and Bt176) were used, and specific primer pairs were designed to detect each line. Using this method, the different lines of GM Maize were monitored from raw products and processed foods in Korean market. Some of the maize processed foods and raw materials were shown to contain more than one foreign gene. This method was found to be effective for-detecting five different GM Maize in a single reaction.