• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.2
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• pp.28-34
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• 2014

A non-contact type measurement system is specially devised to measure the width of a piston ring groove in the grinding process. This system comprises a line camera with an imaging lens, collimated white light source, and a one axis translation stage. When the measurement system movesalong the diagonal direction of the cylinder, the line camera captures an image. By analyzing such images, the width of the piston ring groove can be determined. The experimental results prove that the proposed system is useful, especially as a monitoring system in grinding piston ring grooves on cylinders with accuracy of several micrometers in an area of dozens of millimeters.

• Journal of Multimedia Information System
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• v.8 no.4
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• pp.285-294
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• 2021

The development process of domestic CG (Computer Graphics) needs to be studied by classifying the technical part and the design part. This paper analyzes how early domestic broadcast equipment evolved and focused on what went through the development process. Domestic broadcasting companies have introduced and used overseas equipment and have begun to develop their own technology. The development process of the early domestic production technology of broadcasting stations was classified into Character Generator, On-line Real-Time Graphic and Sport Coder. It was found that the orientation of broadcasting technology was conclusively focused on visualization, with socio-cultural factors acting along with the evolution of hardware and software. This research is meaningful in reorganizing the history of the development process of domestic CG technology in the early days through previous research (primary verification), newspaper articles and news coverage (secondary verification). This paper looks at what is missing by regaining the past of CG, and argues that with the advent of new technologies today, we must develop through appropriate division of roles and collaboration between engineers and designers.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.5
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• pp.77-87
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• 1995

In-process detection of drill wear is one of the most important technoligies for automatic, unmaned machining systems. In this study, an on-line drill wear estimation model based on spindle/Z-axis motor currents generated during the drilling process is proposed. The theoretical model is obtained by integrating the drilling process model and the servomechanism model. The drilling process model describes the relationship of drill wear and drilling torque/ thrust force, whereas the servomechanism model describes the relationship of drilling torque/ thrust force applied to motor and spindle/Z-axis motor current. Evaluation tests have shown that the proposed model is a good real-time estimator for drill wear.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.4
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• pp.591-598
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• 2012

Denitrification is an important biological mechanism in wastewater treatment process because this process is technically to remove nitrogen from water to air. There have been lots of study about denitrification engineering and molecular biological research about denitrifying bacteria, respectively. However, combination of these researches was unusual and rare. This study is about the correlation between quantity of denitrifying bacteria and denitrification potential, and consists of NUR batch test as analysis method of denitrification potential and quantitative molecular analysis for denitrifying bacteria. Three reactors (A/O, MLE and A/O of nitrogen deficiency) are operated to get activated sludge with various denitrification potential. All samples which were acquired from reactors were measured denitrification potential by NUR test and NUiR test. Also, Real-time PCR was conducted for quantification of denitrifying bacteria composition in activated sludge. The various denitrification potentials were measured in the reactors. The denitrifiaction potential was the highest in MLE process and the reactor of the nitrogen deficiency showed the lowest. Genomic DNA of activated sludge was obtained and consequently, real-time PCRuse the primer sets of nirK and nirS　were conducted to quantify genes involving denitrification reductase production. As the result of real-time PCR, nirK gene showed more significant influence on denitrification potential comapred with nirS gene.

• Journal of Pharmaceutical Investigation
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• v.37 no.6
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• pp.329-338
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• 2007

The quality assurance issue of drug products is more important than the general product because it is highly related to the human health and life. In this reason, the regulatory guide lines have continuously been intensified all around the world. In order to achieve effective quality assurance and real-time product release (RTPR) of drug products, process analytical technology (PAT), which can analyze and control a manufacturing process, has been proposed from the United States. With the PAT process, we can obtain significant process features of materials, quality characteristics and product capabilities from a raw material to the final product in the real-time procedure. PAT can also be utilized to process validation using information system that can analyze the risk of drug products through out an entire product life-cycle. In this paper, we first offered a new concept for the off-line process design methods to prepare the improved quality assurance restrictions and a real-time control method by establishing an information system. We also introduced an automatic inspection system by obtaining surrogate variables based on drug product formulations. Finally, we proposed an advanced PAT concept using validation and feedback principles through out the entire life-cycle of drug product manufacturing processes.

• Journal of KIBIM
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• v.9 no.4
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• pp.51-61
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• 2019

In the general manufacturing sector, prototyping used to reduce the risks that can arise with new conceptual products. However, in AEC area, it does not mass-produce a building, so the prototype itself becomes a building. Therefore, it is challenging to have prototyping of the same scale as the real thing, and the prototyping process in architecture is very inefficient. The prototyping process in the design stage typically assumes making a scaled model, partial model, or digital model. However, it is difficult for these models to correspond to the actual building and the environment of time and space such as scale, material, environment, load, physical properties and deformation, corrosion, etc., unlike the actual building. When using the digital twin concept in the prototyping process, it is possible to measure performance from the design stage to the operation stage. The digital twin was found by a method for monitoring based on physical twins and real-time linkage in the operation stage. Therefore, if the digital twin concept is applied at the design stage, it is possible to predict performance using not only current performance but also history information using real-time information. In order to apply the digital twin concept to the prototyping design process, we analyze the theoretical considerations and the prototyping design process of the digital twin, analyze the cases and research results where the prototyping design was applied, Provide an applied prototyping design process. The proposed process is tested through a pilot project and analyzed for potential use.

• International Journal of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.26-34
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• 2018

In this paper, we propose a scheduling scheme that can efficiently serve I/O requests having deadlines in flash storage. The I/O requests with deadlines, namely, real-time requests, are assumed to be issued for streaming services of continuous media. Since a Web-based streaming server commonly supports downloads of HTMLs or images, we also aim to quickly process non-real-time I/O requests, together with real-time ones. For this purpose, we adopt the well-known rate-reservation EDF (RR-EDF) algorithm for determining scheduling priorities among mixed I/O requests. In fact, for the use of an EDF-style algorithm, overhead of task's switching should be low and predictable, as with its application of CPU scheduling. In other words, the EDF algorithm is inherently unsuitable for scheduling I/O requests in HDD storage because of highly varying latency times of HDD. Unlike HDD, time for reading a block in flash storage is almost uniform with respect to its physical location. This is because flash storage has no mechanical component, differently from HDD. By capitalizing on this uniform block read time, we compute bandwidth utilization rates of real-time requests from streams. Then, the RR-EDF algorithm is applied for determining how much storage bandwidth can be assigned to non-real-time requests, while meeting deadlines of real-time requests. From this, we can improve the service times of non-real-time requests, which are issued for downloads of static files. Because the proposed scheme can expand flexibly the scheduling periods of streams, it can provide a full usage of slack times, thereby improving the overall throughput of flash storage significantly.

• Spatial Information Research
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• v.17 no.3
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• pp.319-328
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• 2009

The growth of sensor and wireless communication technology enable us to monitor the status of things in real-time. There are many attempts to apply the real-time monitoring in various fields. Especially, the real-time monitoring in facility management fields has attracted much attentions recently. But it is difficult to apply recent technologies including sensor, wireless communication and Geospatial information technologies, etc, to the real situation directly. One of the reasons is that facility managers who are familiar with existing processes may resist the change induced by new technologies. So it is necessary to close the gap between new technologies and existing processes by improving the existing processes prior to putting them in the field. In this paper, we suggest the management process improvement focused on the district heating facilities.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.1
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• pp.9-14
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• 2003

In this study we suggest real-time simulator that could describe rent system without ordinary DSP card. This simulator is composed of 80196kc-16bit ordinary microprocessor, which is widely used up to now and personal computer. DSP card that has calculated complex numerical equation is replaced by personal computer and 80196kc generates control signals independently out of the personal computer. In all process personal computer is synchronized with one-board microprocessor (80196kc) within sampling time in the closed loop system. This makes it possible to be described in hydraulic servo system in real time.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.472-477
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• 1996

This paper presents a new approachtothe design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles. Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme, adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaaptive feedforward controller, feedback controller, and PID type time-varying auxillary control elements. The prpposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.