• Journal of the Korean housing association
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• v.10 no.1
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• pp.51-61
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• 1999

Small apartment housings in Korea are dissatisfied due to the growing areas and changing lifestyle of the residents. Many of them currently confronted with slum areas and kinds of housing stock accumulated much more in Korean contexts. An extention of the existing small houses could be an adaptation model to the increasing requirement standards of the house residents. The new model could support diverse identification of the dwelling model in a settlement and many residents could be satisfied with the settlement. This paper deals with the unification typology of two dwelling units to one in order to remodel existing small apartment houses on the 15-pyung areas (N type) constructed by Korea National Housing Corporation in Naju. The proposed type of the merging of the dwellings remove concrete panel walls, make a path through balcony and attach a living areas to the front of the houses in order to make a circulation between the dwellings. A stair hall can be located in-between or inside the merged houses. It can also enhance privacy against conflictive activities in a house and possibly provide space appropriate for three-generation living. It can be devided for the multi-family use. Finally, the merging types of two dwelling units into one can be used as a device to get rid of the monotonous characteristics and gain diversity in the declining stock housing.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.5 s.236
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• pp.770-776
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• 2005

The gains fur NC controller parameter are fixed when the controller is combined with a machine. However, the characteristics of controller could be changed as it has being used by the machine or other environmental conditions. Those result in that the tool positioning accuracy is influenced. The loading torque in servo motor influences on the tool positioning accuracy and it is controlled by the parameter gains. It is required to analyze the torque variation with angular positioning accuracy of the servo motor. This study focus on a measuring method and device for verifying angular positioning accuracy of NC servo motor. We used a high resolution An converter for acquiring analogue signal of rotary encoder in servo motor. The positional accuracy for a nominal tool path, which is generated by the combination of axial movements (X,Y,Z), is analyzed with the servo motor torque. The current variation signal is acquired at the power line using a hall sensor and converted to the loading torque of servo motor. The method of measurement and analysis proposed in this study will be used for determining the gains of parameter in NC controller. This gain tuning is also necessary when the controller is set up at a machine.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.135-140
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• 2010

This paper presents a sensorless speed control of BLDC Motor using terminal voltage of the one phase. Rotor position information is extracted by indirectly sensing the back EMF from only one of the three terminal voltages for a three-phase BLDC motor. Depending on the terminal voltage sensing rotor position, active filter is used for position information. This leads to a significant reduction in the component device of the sensorless circuit. Therefore this is a advantage for the cost saving and size reduction. With indirect sensing methods based on detection of the terminal voltage that require active filtering, the position information needs the six divider section by PLL circuit, the binary counter and johnson counter by the EPLD. Finally, this algorithm can estimate the rotor position information similar to Hall-sensor sticked the three-phase BLDC motor. As a result, the method described that it is not sensitive to filtering delays, allowing the motor to achieve a good performance over a wide speed range. In addition, a simple starting method and a speed estimation approach are also proposed. Experimental and simulation results are included to verify the proposed scheme.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.615-618
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• 2009

In order to apply for transparent conductive oxide(TCO), we deposited ZnO thin film on the glass at room temperature by RF magnetron sputtering method. Deposition conditions for low resistivity were optimized in our previous studies. Under the deposition condition with the RF power of 800 [W]. Sheet resistance and surface roughness of ITO and ZnO thin film were measured by Hall-effect measurement system and AFM, respectively. The sheet resistance of ITO and ZnO thin film were 7.290 [$\Omega$] and 4.882 [$\Omega$], respectively. and surface roughness were 3.634 [nm] and 0.491 [nm], respectively. Green OLED was fabricated with the structure of TPD(400 [$\AA$])/Alq3(600 [$\AA$])/LiF(5 [$\AA$])/Al(1200 [$\AA$]). Turn-on voltage of green OLED applied ITO was 7 [V] and luminance was 7,371 [$cd/m^2$]. And, Turn-on voltage of green OLED applied ZnO was 14 [V] and luminance was 6,332 [$cd/m^2$].

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.5
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• pp.792-799
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• 2017

The real time unmanned monitoring system of an equipment's internal parts and condition requires the monitoring device to be able to stop at a set location on the rail. However, due to the slip between the driving surface and the roller, an error occurs between the actual position and the command position. In this paper, a method to compensate the position error due to the roller slip is proposed. A proximity sensor located at both ends of the rail detects the starting point and the maximum position pulse, linearly compensating the error between the angular position of the motor and the mechanically fixed starting and maximum position pulse of the rail in forward and reverse direction. Moreover, unlike the existing servo position controller, the motor adopts the position detection method of Hall sensor in BLDC (Brushless DC) and applies an algorithm for low-speed driving so that a stable position control is possible. The proposed rail guided unmanned monitoring system with driving slip compensator was tested to verify the effectiveness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.77-78
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• 2006

In order to increase the efficiency of LED, transparent electrodes should be also developed. also suitable anti-reflection coating (ARC) is necessary for practical device applications. In our paper, Al-doped ZnO (AZO) films were fabricated by sputtering on GaP substrate(wavelength:620nm). Choosing optimum substrate temperature and sputtering rate, high quality AZO films were formed. We confirmed that the surface and electrical properties, which implemented using the methods of AFM, Hall measurement. The properties of AZO thin films especially depended on the thickness. We presumed that the change of the increase the external quantum efficiency of LED according to the AZO thin film of thickness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.232-232
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• 2006

SiC single crystal Ingots were prepared onto different seed material using sublimation PVT techniques and then their crystal quality was systematically compared. In this study, the conventional SiC seed material and the new SiC seed material with an inserted SiC epitaxial layer on a seed surface were used as a seed for SiC bulk growth. The inserted epitaxial layer was grown by a sublimation epitaxy method called the CST with a low growth rate of $2{\mu}m/h$ N-type 2"-SIC single crystals exhibiting the polytype of 6H-SiC were successfully fabricated and carrier concentration levels of below $10^{17}/cm^3$ were determined from the absorption spectrum and Hall measurements. The slightly higher growth rate and carrier concentration were obtained in SiC single crystal Ingot grown on new SiC Seed materials with the inserted epitaxial layer on the seed surface, maintaining the high quality.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2207-2210
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• 2005

Guest guidance system based on the compact battery-less information terminal, Aimulet, which has been developed by the authors of the National Institute of Advanced Industrial Science and Technology (AIST), Japan. Conventional Aimulet, which is Aimulet ver.1 or CoBIT, has features of location and direction sensitive information service device without batteries. On the other hand, the Aimulet has two subjects, one is multiplex and demultiplex of some contents, and the other is operation under sunshine. Former subject is of solved by the wavelength multiplex technique using LED emitter with different wavelength and dielectric optical filters. Latter subject is solved by new micro spherical solar cells with a visible-light-eliminating optical filter and a new design of light irradiation. These techniques are applied to the EXPO 2005, Aichi Japan and introduced in public. Aimulet GH is Former technique is applied on Aimulet GH, which is used in Orange Hall of the Global House, scientific museum with a fossil of a frozen mammoth.

• International journal of advanced smart convergence
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• v.5 no.3
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• pp.32-39
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• 2016

With the help of a small wearable device, patients reside in an isolated village need constant monitoring which may increase access to care and decrease healthcare delivery cost. As the number of patients' requests increases in simultaneously manner, the web service gateway located in the village hall encounters limitations for performing them successfully and concurrently. The gateway based RESTful technology responsible for handling patients' requests attests an internet latency in case a large number of them submit toward the gateway increases. In this paper, we propose the design tasks of the web service gateway for handling concurrency events. In the procedure of designing tasks, concurrency is best understood by employing multiple levels of abstraction. The way that is eminently to accomplish concurrency is to build an object-oriented environment with support for messages passing between concurrent objects. We also investigate the performance of event-driven architecture for building web service gateway using node.js. The experiments results show that server-side JavaScript with Node.js and MongoDB as database is 40% faster than Apache Sling. With Node.js developers can build a high-performance, asynchronous, event-driven healthcare hub server to handle an increasing number of concurrent connections for Remote Healthcare Monitoring System in an isolated village with no access to local medical care.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.140-142
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• 2003

ZnO thin films are demanded for device applications, so ZnO buffer layer was used to improve for good properties of ZnO thin film. In this study, the structural, electrical and optical properties of ZnO thin films deposited with various buffer thickness was investigated by X-ray diffraction (XRD), Hall measurements, Photoluminescence(PL). ZnO buffer layer and ZnO thin films on sapphire($Al_{2}O_{3}$) substrate have been deposited $200^{\circ}C$ and $400^{\circ}C$ respectively by pulsed laser deposition. It is observed the variety of lattice constant of ZnO thin film by (101) peak position shift with various buffer thickness. It is founded that ZnO thin film with buffer thickness of 20 nm was larger resistivity of 200 factor and UV/visible of 2.5 factor than that of ZnO thin films without buffer layer. ZnO thin films with buffer thickness of 20 nm have shown the most properties.