• Journal of Internet of Things and Convergence
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• v.3 no.1
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• pp.25-31
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• 2017

In the future a future type new city and the latest apartment will be built, and the IoT technology will be constructed and combined in large numbers indoors of ordinary households. An air cleaner that makes people in it comfortable is built in, and the suction port that sucks in the air of the air purifier and the discharge port that discharges it are set up around the room and come out. However, this is impossible to adjust because there is only a central switch on / off. Also, consuming a lot of electricity so that many electricity charges are caused by huge electricity consumption will eventually be a waste of resources. This would like to be adjusted and driven through the fine dust detection device to the room built-in air purifier and that has provided a solution to save electricity. In addition, since it exists in and around the room, you can grasp the position of the person and connect to the home network to enhance the convenience. Also, through analysis of the air, we provide a health-check solution that checks the user's health and adjusts it appropriately.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1320-1326
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• 2017

Recently, IoT has been studying a lightweight protocol to satisfy device communication in a limited network environment. MQTT is a typical lightweight protocol. It supports small fixed headers to minimize overhead, and adopts publish/subscribe structure to guarantee real-time performance. However, MQTT does not support prioritization of important data and can not provide QoS in a specific IoT service. In this paper, we propose a message processing method to consider the priority of various IoT services in MQTT. In the proposed method, the priority flag is added to the fixed header of the MQTT in the node to transmit the message, and the broker confirms the priority of the corresponding message and processes it preferentially. Through experiment and evaluation, we confirmed the reduction of end-to-end delay between nodes according to priority.

• The Transactions of the Korea Information Processing Society
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• v.3 no.1
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• pp.191-199
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• 1996

In this paper, We assume that the closed computer system model composed of multiprocessor system is analyzed by BCMP queueing network theory with priority levels. In this system that contains terminals, processors and I/O devices, We show maximum throughput and the number of active terminals in the optimum multiprogramming levels. It is compared the performance with the other. In the result, it is obtained the optimum number of processors and active terminals. Therefore, the system model consisted of the optimum number of processor and multiprogramming level m is analyzed by the servers with a priority level. Each server is applied to the type of server which is characterized terminal, processor I/O device etc.. This model is analyzed by the server with a probability ditribution. Ideal state is proposed by the modeling for priority levels. Finally, we try to increase the performance in overload system.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.8
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• pp.707-712
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• 2014

Aircraft fuel indicator is a device to indicate the amount of fuel remained during flight, where accurate and consistent operation of the indicator should be maintained. Previously the Korean Utility Helicopter fuel indicator sporadically displayed abnormal sign by "8888" during flight, jeopardizing flight safety. Inappropriate EMI/EMC performance was detected during trouble shooting process. The cause of the abnormal display was found to be resulted from unstable power induced by electro-magnetic disturbance and CAN communication error. The aircraft fuel indicator design was improved and the design compatibility was verified to avoid abnormal display.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.498-498
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• 2013

Atmospheric Pressure Plasmas have pioneered a new field of plasma for biomedical application bridging plasma physics and biology. Biological and medical applications of plasmas have attracted considerable attention due to promising applications in medicine such as electro-surgery, dentistry, skin care and sterilization of heat-sensitive medical instruments [1]. Traditional approaches using electronic devices have limits in heating, high voltage shock, and high current shock for patients. It is a great demand for plasma medical industrial acceptance that the plasma generation device should be compact, inexpensive, and safe for patients. Microwave-excited micro-plasma has the highest feasibility compared with other types of plasma sources since it has the advantages of low power, low voltage, safety from high-voltage shock, electromagnetic compatibility, and long lifetime due to the low energy of striking ions [2]. Recent experiment [2] shows three-log reduction within 180-s treatment of S. mutans with a low-power palm-size microwave power module for biomedical application. Experiments using microwave plasma are discussed. This low-power palm-size microwave power module board includes a power amplifier (PA) chip, a phase locked loop (PLL) chip, and an impedance matching network. As it has been a success, more compact-size module is needed for the portability of microwave devices and for the various medical applications of microwave plasma source. For the plasma generator, a 1.35-GHz coaxial transmission line resonator (CTLR) [3] is used. The way of reducing the size and enhancing the performances of the module is examined.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.185-192
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• 1995

A common control model used to implement computer integrated manufacturing(CIM) is based on the hierarchical decomposition of the shop floor activities, in which supervisory controllers are responsible for all the interactions among subordinates. Although the hierarchical control philosophy provides for easy understanding of complex systems, an emerging manufacturing paradigm, agile manufacturing, requires a new control structure necessary to accommodate the rapid development of a shop floor controller. This is what is called CSCW(computer supported cooperative work)-based control or component-based heterarchical control. As computing resources and communication network on the shop floor become increasingly intelligent and powerful, the new control architecture is about to come true in a modern CIM system. In this paper, CSCW-based control is adopted and investigated, in which a controller for a unit of device performs 3 main functions - planning, scheduling and execution. In this paper, attention is paid to a planning function and all the detailed planning activities for CSCW-based shop floor control are identified. Interactions with other functions are also addressed. Generally speaking, planning determines tasks to be scheduled in the future. In other words, planning analyzes process plans and transforms process plans into detailed plans adequate for shop floor control. Planning is also responsible for updating the process plan and identifying/resolving replanning activities whether they come from scheduling or execution.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.251-258
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• 2016

Recently, the demand for fast storage devices is rapidly increasing in cloud platforms, social network services, etc. Despite the development of fast storage devices, the traditional Linux I/O stack is not able to exploit the full extent of the performance improvement since it has been optimized for disk-based storage devices. In this paper, we propose an optimized I/O stack which can fully utilize the I/O bandwidth and latency of fast storage devices. To this end, we design a new I/O interface to replace the current block I/O interface and optimize our I/O interface. Our optimized I/O interface bypasses operations/layers in block I/O subsystems of the current Linux I/O stack to fully exploit fast storage devices. We also optimize the Linux file systems such as ext2 and ext4 to run on our I/O interface. We evaluate our I/O stack with multiple benchmarks and the experimental results show that our I/O stack achieves 1.7 times better throughput compared to traditional Linux I/O stack.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1849-1856
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• 2012

This paper proposes a method to track the center of pupil and perform the remote control for interface based on the substituted commands according to movements of pupil under smart phone environment. The proposed method, which is a remote control through the movement of eyes, may be helpful for the handicapped people or users who want a more convenient input method. A method based on webcam, which is representative one among the previous methods to track pupil of user, has a few limitations on distance and angle between location of user and webcam. However, this paper uses smart phone that is convenient to carry. The proposed method can perform the remote control through tracking of pupil using wireless network without any restriction on the location of users. Thus, the method is effectively applied for controlling the smart TV that should be controlled on the distance as well as the remote control for PC.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.619-622
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• 2007

PDA provides an opportunity for users to study anytime and anywhere because it is portable and convenient thanks to its relatively small size. However, users may face difficulties to fully recognize the characters provided through lecture videos, due to its low resolution and small scaled screen. This thesis proposes a system of remote lecture in which the size of videos can be adjusted and transmitted on the basis of contents necessary for study, using detection of region-of-interest(ROI) image, and a method of image scaling in a bid to solve such a problem of PDAs. The experiment on 802.11b wireless network shows that the proposed system is able to provide more optimized lecture videos than in existing method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.11
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• pp.2433-2440
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• 2009

Whole system and network for supply of electric power and electricity safety are essential element. Electricity safety technology need rating for product and research about certification as product development that is done electric power u-IT cotton flannel mixed with development of u-IT, u-City base technology consists. Study on serve to develop electricity safety integration supervision system to apply product to u-City electric power appliance and cotton flannel mixed of u-IT appliance, Connection badness sensing instrument made device built-in electric power u-IT cotton flannel mixed in outlet that is used most in electric power appliance terminal. Using sensor on ZigBee, RFID performance estimation of communication module about function of product for remote safety check of electricity safety integration supervision system. A performance experiment and estimation in electric leakage, high voltage, Arc, fire detection diagnosis system and certification KS, electricity safety about product that get fitness finding.