• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.45-45
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• 2000

This paper proposes a remote control system that combines computer network and an autonomous mobile robot. We control remotely an autonomous mobile robot with vision via the internet to guide it under unknown environments in the real time. The main feature of this system is that local operators need a World Wide Web browser and a computer connected to the internet communication network and so they can command the robot in a remote location through our Home Page. The hardware architecture of this system consists of an autonomous mobile robot, workstation, and local computers. The software architecture of this system includes the server part for communication between user and robot and the client part for the user interface and a robot control system. The server and client parts are developed using Java language which is suitable to internet application and supports multi-platform. Furthermore, this system offers an image compression method using motion JPEG concept which reduces large time delay that occurs in network during image transmission.

• The Journal of Internal Korean Medicine
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• v.21 no.1
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• pp.31-38
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• 2000

Background : Nowadays asthma is considered to be the inflammatory disease characterized by airway hyperresponsiveness and pulmonary eosinophilia, and mediated by Th lymphocytes expressing the Th2 cytokine pattern. In many recent studies, molecular biological methods have been used to investigate the role of cytokines in pathogenesis and new therapeutic targets of asthma. Objective : We aimed to identify the effect of Armeniacae Arnarum Semen and Platycodi Radix on the transcriptional activities of cytokine IL-4, IL-5 and IL-6 involved in asthma model. Materials and Methods : RBL-2H3 cell lines were used. Cells were stimulated with calcium inophore for maximal gene expression. After 24 hours of Armeniacae Arnarum Semen and Platycodi Radix-treatment, total cellular RNAs were collected using Trizol solution method. Then transcriptional activities of IL-4, IL-S and IL-6 were measured by RT-PCR with electrophoresis. Results : In IL-4 study, Armeniacae Arnarum Semen treated group showed 48.4% of transcriptional activities compared to the control group and Platycodi Radix treated group showed 45.4% of transcriptional activities compared to the control group. In IL-5 study, Armeniacae Arnarum Semen treated group showed 52.7%of transcriptional activities compared to the control group and Platycodi Radix treated group showed 60.2% of transcriptional activities compared to the control group. In IL-6 study, Armeniacae Amarum Semen treated group showed 42.3% of transcriptional activities compared to the control group and Platycodi Radix treated group showed 69.1% of transcriptional activities compared to the control group. Conclusion : This study shows that Armeniacae Arnarum Semen and Platycodi Radix have the inhibitory effect on the transcription of IL-4, IL-5 and IL-6 gene expression in RBL-2H3 cell lines. Advanced studies are required to investigate the mechanisms of inhibition by herbal medicine in asthma model.

• 한국가시화정보학회:학술대회논문집
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• 2007.11a
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• pp.92-96
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• 2007

Internal flow characteristics for an automobile HVAC have been investigated using a high-resolution PIV technique. The PIV system consists of a 2-head Nd:YAG laser(125 mJ), a high-resolution CCD camera($2K\;{\times}\;2K$), optics and a synchronizer. An automobile HVAC module was used directly. Only the casing was remodeled transparently for capturing flow image and laser sheet beam illumination. Time-averaged velocity field were measured in three temperature control mode. For three temperature control modes, the internal flow characteristics for an automobile HVAC system were evaluated from PIV results..

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.8
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• pp.530-537
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• 2010

With the advancement of technology, the density of IT equipment, heat load and power consumption continue to increase in high density internal-load dominated buildings as datacenters. To improve the HVAC system's energy performance and efficiency, there is a need to find methods of using outside air. Through cooling tower control that is based on outside wet-bulb temperature, the water-side economizer made it possible to achieve a maximum energy performance improvement of about 16.6% over the basic chilled water system, whereas the air-side economizer, through control based on outdoor air enthalpy, made it possible to achieve about 42.4% improvement.

• Journal of Power System Engineering
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• v.17 no.3
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• pp.82-88
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• 2013

For commercialized servo drives of the motion stage to include embedded controller, external terminal is provided for tracking command and encoder output, but internal terminal is not for control input. Thus, it is difficult to combine out signal of embedded controller with that of external compensator such as disturbance observer. In this study, for precise tracking control of motion stage without hardware change of the servo drive, tacking control system is composed of an inner loop of servo drive and an outer loop of disturbance observer. Then, the control system is designed so that the output response of actual plant corresponds with nominal model's in transient state as well as in steady state. Finally, the experiment results show that the designed control system is effective to reconcile actual plant behavior with nominal model under nonlinear friction and parameter perturbation.

• International journal of advanced smart convergence
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• v.11 no.4
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• pp.28-40
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• 2022

Although precise temperature control in the heat treatment process is a key factor in process reliability, there are many cases where there is no separate heat source control optimization system in the field. To solve this problem, the program monitors the temperature data according to the heat source change through sensor communication in a recursive method based on multiple variables that affect the process, and the target heat source value and the actual heat treatment heat source to match the internal air temperature and material temperature. A control optimization system was constructed. Through this study, the error rate between the target temperature and the atmosphere (material surface) temperature of around 10.7% with the existing heat source control method was improved to an improved result of around 0.1% using a process optimization algorithm and system.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.433-439
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• 2015

Enclosures for CCTV internal short circuit are prevented due to wetting to maintain a constant humidity and temperature, to avoid condensation due to temperature difference, a constant temperature and humidity requirements of the equipment, such as high-temperature resistant and a constant temperature of the structure, degree of energy utilization is optimized for developing this corresponding housing automatic control system and humidity is required. Device being an expensive imaging equipment in side of the enclosure according to the temperature conversion from a hazard protection, there is a need for a constant temperature and humidity control apparatus that can prevent a short-circuit failure. This is a system in which the accessory device is absolutely required for the storage and transmission of an image in recording reliability and field conditions.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.3
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• pp.137-148
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• 2020

The purpose of this study is to investigate factors influencing risk assessment of material misstatement in Vietnamese enterprises listed on stock market. Expert interview method was conducted to discover the scales for three variables including information system, trademark, and risk assessment of material misstatement. Survey method was used to examine the impacts of eight factors on risk assessment of material misstatement. Data is collected from 317 auditors who have excellent experience in auditing financial statements of companies listed on stock market. Then, data is processed by descriptive statistics, reliability analysis, factor extracted analysis, correlative regression analysis, and analysis variance of residual change. The research findings showed that business characteristic, stakeholder pressure, and economic environment have positive relationships with risk assessment of material misstatement. Three variables including operation control and monitor, control environment, and information system negatively affect to risk assessment. Specially, business characteristic and information system, which are elements in internal control, have strongest impact on risk assessment. One the other hand, assessment of internal control plays an important role not only in the audit plan stage but also throughout the stages of the audit implementation and ending. Therefore, appropriate solutions are proposed to carry out all audit stages.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.1
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• pp.83-95
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• 2010

This paper considers a firm that operates make-to-stock and make-to-order facilities in successive stages. The make-to-stock facility produces components which are consumed by the external market demand as well as the internal make-to-order operation. The make-to-order facility processes customer orders with the option of acceptance or rejection. In this paper, we address the problem of coordinating how to allocate the capacity of the make-to-stock facility to internal and external demands and how to control incoming customer orders at the make-to-order facility so as to maximize the firm's profit subject to the system costs. To deal with this issue, we formulate the problem as a Markov decision process and characterize the structure of the optimal inventory allocation and customer order control. In a numerical experiment, we compare the performance of the optimal policy to the heuristic with static inventory allocation and admission control under different operating conditions of the system.

• Journal of Platform Technology
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• v.10 no.4
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• pp.62-69
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• 2022

Flight control systems installed on unmanned aircraft require thorough verification from the design stage. This verification is made through the integrated flight control test environment. Typically, a debugger is used to monitor the internal state of a flight control computer in real time. Emulator with a real-time memory monitor and trace is relatively expensive. The JTAG Emulator is unable to operate in real time and has limitations that cannot be caught up with the processing speed of latest high-speed processors. In this paper, we describe the results of the development of internal monitoring software for drone flight control computer processors based on NUTTX/PIXHAWK. The results of this study show that the functions provided compared to commercial debugger are limited, but it can be sufficiently used to verify the flight control system using this system under limited budget.