• Journal of the Korea Society of Computer and Information
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• v.13 no.2
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• pp.211-220
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• 2008

The home network technology which used USN is developing quickly. Use yet line to a lot of part as home network technology. Recently be leap into prominence to technology core of home network as wireless technology a ZigBee. ZigBee Perceive with cognition from tag and sensor as use USN, and processing, save, integration, and provide information. Implement the access control system which used technology BigBee with design at these papers. The wireless-based construction that used ZigBee. The influence that can let you implement early a Ubiquitous society is technology there being. Also, show by a large spinoff in an allied industry field, and improve the quality of life, and invention calls value added of leading edge IT service and product. The implementation of mobile base on access control system using zigbee method is expected to be helpful for the convenience in home network use.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.675-684
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• 2012

Recently, a heavy rainfall under climate change causes the flood exceeded river's conveyance. Flood control methods under the limited river width are the increase of embankment, the construction of storage pockets and diversion channel, the dredging of river bed. Hwasun flood control reservoir of washland is designed as the storage pockets and the regulating gate for the control of water level. In this study, the propriety of design was investigated through hydraulic experiments for the circumstances to exclude the constant flood discharge during operation period. In the results, the over flow rate of side weir exceeded the flow of design and indicated to be able to discharge the designed flow in the regulating gate opened 1.1 m. The high velocity 7.1 m/s behind the gate has investigated to reduce under 3.3 m/s by the baffle block.

• Fire Science and Engineering
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• v.27 no.4
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• pp.1-6
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• 2013

When the pressurization system that uses difference of pressure for smoke control is designed, the factors influencing on the pressure field in building should be applied to design process and the stack effect is one of the main factors. Numerical analysis based on network model in 20-story building is carried out to analyze the pressurization system of smoke control in consideration of stack effect. Calculations are conducted for three conditions, that is, stack effect only, pressurization only and stack effect plus pressurization. Results including the detailed pressure field and flow rate at each floor are represented and the stack effect are effectively visualized. Meanwhile, the pressure of stairwell is increased as much as the summation of the stack effect and pressurization, and the problem induced by rise of pressure is pointed out.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1350-1352
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• 2003

For developing a 100 kW MCFC power generation system, Several design parameters for a fuel cell stack and system analysis results by Cycle Tempo, a processing computer soft ware, were described. Approximately two substacks with 90 cells are required to generate 100 kW at a current density of $125\;mA/cm^2$ with $6000\;cm^2$ of cells. An overall heat balance was calculated to predict exit temperature. The 100 kW power is expected only under pressurized operation condition at 3 atm. Recycle of cathode gas by more than 50% is recommended to run the stack at $125\;mA/cm^2$ and 3 atm. Manifolds should be designed based on gas flow rates for the suggested operating condition. The fuel cell power generation system was designed conceptually with several choices of utilization of anode exhaust gas. To operate and evaluate the MCFC system, control and measurement system and operation mode are designed before 100 MCFC system construction. In system control schematics, OS, PLC and MMI were consisted and have roles for MCFC system control. For operation of 100 kW MCFC system, NS, PS PR mode were considerated step by step and simulated.

• Journal of Information Management
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• v.40 no.3
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• pp.1-21
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• 2009

This study aims to suggest some idea for construction of headings in authority records to improve conventional method for authority control. The reference structure between established form and other forms was replaced by the link structure based on access points and adopting standard authority numbers was considered. Additional elements such as work information to distinguish homonym and notational system of the headings to promote sharing of authority records were also addressed. Authority records management system was constructed to test structure of headings suggested in this study, too. Through this research, we confirmed that management, identification, and sharing of authority records were considerably improved compared with the conventional authority control system.

• Parasites, Hosts and Diseases
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• v.53 no.2
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• pp.147-154
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• 2015

Various constituents in clinical specimens, particularly feces, can inhibit the PCR assay and lead to false-negative results. To ensure that negative results of a diagnostic PCR assay are true, it should be properly monitored by an inhibition control. In this study, a cloning vector harboring a modified target DNA sequence (${\approx}375bp$) was constructed to be used as a competitive internal amplification control (IAC) for a conventional PCR assay that detects ${\approx}550bp$ of the Cryptosporidium oocyst wall protein (COWP) gene sequence in human feces. Modification of the native PCR target was carried out using a new approach comprising inverse PCR and restriction digestion techniques. IAC was included in the assay, with the estimated optimum concentration of 1 fg per reaction, as duplex PCR. When applied on fecal samples spiked with variable oocysts counts, ${\approx}2$ oocysts were theoretically enough for detection. When applied on 25 Cryptosporidium-positive fecal samples of various infection intensities, both targets were clearly detected with minimal competition noticed in 2-3 samples. Importantly, both the analytical and the diagnostic sensitivities of the PCR assay were not altered with integration of IAC into the reactions. When tried on 180 randomly collected fecal samples, 159 were Cryptosporidium-negatives. Although the native target DNA was absent, the IAC amplicon was obviously detected on gel of all the Cryptosporidium-negative samples. These results imply that running of the diagnostic PCR, inspired with the previously developed DNA extraction protocol and the constructed IAC, represents a useful tool for Cryptosporidium detection in human feces.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.217-225
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• 2005

Because of the limitation of controllable operation variables for the wastewater treatment process with variable hydrodynamic flow patterns, it may preclude the use of this type of nutrient removal activated sludge process. As the operation variables, only temperature and dissolved oxygen (DO) have been used to operate the process. This study made an effort to improve treatment efficiency and operability of the process by the following methodologies: 1) process and operation data analysis using process simulation, 2) determination of optimal control logic or algorithm using a pilot-scaled experimental apparatus and its operations, and 3) application of experimental and simulation results to find the optimal process operation modes. In this study, it was found that the optimal operation mode named 'save mode' in the basis of process variables, such as the ammonia-nitrogen concentration of inlet flow, temperature and flow rate, can reduce the operation cost comparing with the present normal operation mode. And the stable conditions in nitrification were also shown by the proportional control of DO with the inlet air flow rate of blower and the mixing rate of mechanical aeration.

• Journal of Drive and Control
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• v.12 no.3
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• pp.36-43
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• 2015

An autonomous vehicle control algorithm based on Ackerman Geometry is known to be reliable in low tire slip situation. However, vehicles at high speed make lateral errors due to high tire slip. In this paper, considering the tire slip of vehicles, the steering angle is determined based on the Ackerman Geometry and is supplemented tire slip angle by the Stanley steering algorithm. In addition, to prevent the tire slip, the algorithm, which restricts steering if a certain level of slip occurs, is used to reduce the lateral error. While many studies have been extended to include vehicle slip, studies also need to be carried out on the tire slip depending on hardware performance. The control algorithm of autonomous vehicles is compensated considering the sensor noise and the performance of steering actuator. Through the various simulations, it was found that the performance of steering actuator was the key factor affecting the performance of autonomous driving. Also, it was verified that the usefulness of steering algorithm considering the tire slip and performance of steering actuator.

• Journal of Drive and Control
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• v.12 no.3
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• pp.52-59
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• 2015

An electro hydraulic poppet valve (EHPV) and a variable orifice poppet are assembled in a single block, which is referred to as a RHINO but is also generally called a pilot-operated flow control valve. In this study, we analyzed the structure and the operating principle for a RHINO applied in a 21-ton electric excavator system. The RHINO was experimentally tested to measure the dynamic responses and the pressure energy loss. In this test, we investigated the variation in the conductance coefficient according to the increase in the supply pressure under a constant current and a variation in the flow rate according to the increase in the current. Then, the geometrical shapes and the spring stiffness of the RHINO were considered to develop an analysis model. The characteristics (current-force and hysteresis) for the solenoid based on the experimental data were reflected in the analysis model that was developed, and the reliability of the analysis model was also verified by comparing the experimental and analytical results. The developed model is thus considered to be reliable for use in a wide range of applications, including optimum design, sensitivity analysis, parameter tuning, etc.

• Plant Journal
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• v.13 no.4
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• pp.48-50
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• 2017

A program for analyzing the transient behaviors of industrial gas turbines was developed. Each component (compressor, combustor, turbine and ducts)of gas turbine is modeled as a fully module to enhance the expandability of the program. We used object-oriented programing for this purpose. The mass and energy balance equations are solved numerically by Multivariable Newton Raphson method. The characteristic maps for the compressor and turbine were used for predicting the performance of a gas turbine engine. Combustion in the combustor is assumed to be complete combustion. PID control is used to maintain constant rotational speed and turbine exhaust temperature by the control of the fuel flow rate and the changing of the compressor inlet guide vane angle at the same time. It was confirmed that stable control of the gas turbine was possible, even for a rapid load change.