• Journal of Information Display
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• v.1 no.1
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• pp.42-47
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• 2000

The relationship between driving voltage and the amount of wall charge in the address period of surface discharge type AC Plasma Display Panel has been investigated. The amount of wall charge on each electrode is obtained simultaneously from the current profiles after applying only one addressing discharge pulse. The wall charge $Q_y$ on the scan electrode Y is almost the sum of $Q_x$ on the address electrode X and $Q_z$ on the sustain electrode Z. The $Q_y$ increased with the driving voltage regardless of the kind of electrode, whereas the addressing $T_d$ decreased. The $Q_x$ and $Q_y$ are increased considerably by blocking voltage $V_z$, whereas $Q_x$ is decreased. The $V_z$ dependence of $Q_x$ $Q_y$ and ${\varrho}_z$ in addressing discharge was $-13{\times}10^{-2}$ (pc/$V_z$), and $60{\times}10^{-2}$ ($pc/V_z$) and $70{\times}10^{-2}(pc/V_z)$, respectively.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.2
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• pp.154-163
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• 2013

Adhesive bonding and plastic welding have been widely used to join two plastic materials together. The goal of this paper is to determine a proper joining technology of a pair of flat panel (FP) photobioreactor (PBR) case. The material of the FP PBR case is polycarbonate (PC) plate. Two types of adhesion, including acryl adhesive and two-part epoxy adhesive, as well as two types of plastic welding technology, including ultrasonic welding and thermal welding, are employed for joining of PC plates. In order to influence of the adhesion and welding conditions on the joining characteristics of the PC plates in operational conditions of the FP PBR case, the morphology in the vicinity of the joined region as well as the water and pressure resistance characteristic are investigated. In addition, the variation of the bonding strength of the joined region and deformation behaviors in the vicinity of the joined region according to the adhesion and welding conditions is examined via the lap-shear test. From the results of basic experiments, proper joining technologies are chosen. Using the chosen joining technologies, the FP PBR case are fabricated to perform full-scale durability experiment. The results of the full-scale durability experiment have been shown that the chosen joining technologies can be applicable to fabricate the FP PBR case.

• Journal of Digital Convergence
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• v.19 no.1
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• pp.11-22
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• 2021

The COVID-19 pandemic has led to distance learning in primary and secondary school. Little has been known whether home ICTs environment is appropriate for the distance learning. This paper aims to assess the current state of ICTs environment at home for the distance learning of children. Using 2012 and 2019 Korean Media Panel Survey, we investigated the number of smart devices owned by households and found differences in ownership by household characteristics. The results showed that the majority of household owned more than one smart devices per child. However, the difference in the proportion of households with less than one device per child varied depending on whether smartphone was included in smart devices. These results imply that public intervention is needed to prevent educational inequality caused by the home ICTs environment for the distance learning.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.137-140
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• 2009

Nowadays, the high performance composite materials are famous for the new construction materials as the construction buildings are bigger and higher. Out of them of all, the fiber reinforced concrete and mortar have been studied to develop and strengthen the performances of concrete, such as tensile strength, durability and the resistibility of crack. Also, it is considered that precast concrete is important alternatives of dry process for saving time, upgrading the material's quality and the productivity. Thus, PC panel is being produced for the use of dry wall as well as exterior finishing materials and it requires lots of tests and studies to be conducted to meet the various functional conditions. According to this study, it is considered that PVA fiber might be more effective than nylon fiber for developing the exterior PC panels.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.1-8
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• 2010

Clients require easy to use of product and operating and industry safety according to the change of a market and a factory. For overcoming it, this paper developed controller of take-out robots that take high speed and superprecision and supplement a week point as use the system based on network. development controller classify teaching pendant and center server PC. Center server PC service the information about all process to supervisor. Teaching pendant is the bridge that service various faculties such as control, user recognition, metallic pattern operation to the user using injection molding. The controller development for taking out injection molded body classify software and hardware. The development of software is divided into three step which is application program, user interface and device driver. the simple device driver is not classified and included in application program. The hardware induce the touch panel and wireless network and construct the effective process control and internet connection. The inject ion cycle of existing system was five second but advanced system has the inner four cycle, process efficiency and product operation through wireless network.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1351-1361
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• 1999

The wide spread of multimedia system demands a large area viewing display device which can inform a message to many people in open area. This paper is about the design of a large area viewing LED panel control system. The control system runs on 16 bit microprocessor MC68EC000 and has following functions: 16 line clock and time, 2 channel priority interrupt, 2 channel direct memory access, 2 channel 12 bit clock and timer, 2 channel infrared remocon receiver, 2 channel RS-232C with 16 byte FIFO, IBM PC/AT compatible keyboard interface, ISA bus, battery backuped real time clock, battery backuped 256 byte SRAM and watch dog timer. The core circuits are implemented to ASIC, considering lower cost, higher reliability, higher performance, smaller dimension, and lower power consumption. This is verified by simulation and fabricated in 0.6 um CMOS SOG processes. The total gate count is 39,083 and the clock frequency is 48 MGz. The fabricated ASIC is mounted on test board.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.131-138
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• 2001

Total number of seven experimental specimens of size 4.6m$\times$2.4m are designed in full scale with due considerations given to the constructability as well as economic applications. Each specimen is made with different shapes of trusses or hooks along the interfacial surface between precast panel and topping concrete to maintain appropriate shear resistance. Structural performances in terms of strength and ductility under flexural load are examined for each specimen with different types of interfacial shear resistance reinforcements. Experimentally obtained flexural strength are also compared with those of analytical predictions. Based on experimental and analytical studies, design equations are suggested for the developed precast prestressed concrete half-slab systems.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.441-444
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• 2003

Polymer concrete has more useful than cement concrete in the strength and durability. So, it is widely utilizing as panel for wall, manhole for communication, foundation and underground connection box, etc. But polymer concrete is a defect that is disadvantageous in economical aspect because cost of resin is expensive. Polymer concrete (PC) using unsaturated polyester resins based on recycled polyethylene terephthalate(PET) plastic waste were used in our study for grasping its mechanical properties such as compressive strength, tensile strength, flexural strength and chemical resistance was tested by dealing with 20% HCl, 30% NaOH. As a result of it, compressive, tensile and flexural strength of PC indicated 752kgf/$\textrm{cm}^2$, 80kgf/$\textrm{cm}^2$ and 243kgf/$\textrm{cm}^2$ kind of satisfaction successively. Also, properties of chemical resistance are superior to those of cement concrete.

• Structural Engineering and Mechanics
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• v.37 no.2
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• pp.177-196
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• 2011

An economic, structurally effective and practically applicable strengthening technique was developed for reinforced concrete (RC) framed buildings. The idea of the technique is to convert the existing hollow brick infill wall into a load carrying system acting as a cast-in-place RC infill wall by bonding relatively thin high strength precast concrete PC panels to the plastered hollow brick infill. For this purpose, a total of eight one-third scale, one bay, one story frames were tested under reversed-cyclic lateral loads. Test frames were designed and constructed with common deficiencies observed in practice. Four different panel types were used for strengthening. Test results showed that both strength and stiffness of the frames were significantly improved by the introduction of PC panels. Experimental results were compared with the analytical approaches suggested by the authors.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.395-397
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• 1996

The existing CPC(Center Position Controller) has unstably performed because of dusts on reflection panel, CCD protector contamination due to high temperature in furnace or other parameters. The reason is that the existing CPC has a Z80 processor as a CPU and only performs low level image processing as a simple edge detector. So the improvement of control system through the development of robust edge detection algorithm overcoming changes of measuring environment is needed. For this, in this study we carefully analyze the image of the strip rolled in occasion that measuring environment is changing, develop the optimal edge detection algorithm to solve the problems, generate the control signal suitable for the existing CPC(Center Position Controller), and propose the capability of application to the actual environment.