• Magazine of the Korea Concrete Institute
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• v.7 no.1
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• pp.117-125
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• 1995

Bond test was carried out to assess the effect of several variables on bond characteristics between reinforcing bar and concrete. Key variables are concrete compressive strength($f_c$'=340, 460, 6513, 904kg/$cm^2$), concrete cover (25, 38, 51, 105, IlOmm), and bar diameter(Dl3 and D22). Confining effect and bar spacing are not taken into account. Thirty-two specimens subjected to uniaxial tension were tested under hypothesis uniform bond stress distribution along the reinforcing bar embeded in concrete. Failure mode was examined and local bond stress versus slip relationship diagrams were represented to show effect of the above variables, also test results(u1timate bond stress) were compared with bond and development provisions of the ACI Building Code(AC1 318-89) and proposed equations from previous research. According to analysis, borld stress and ultimate bond stress increased although compressive strength increased beyond the ACI Building Code upper limit. Therefore in calculating development length. compressive strength effect(exceeding 700kg /$cm^2$) should be accounted.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.3
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• pp.15-20
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• 2007

Low temperature processed ZnO-TFTs on glass below $270^{\circ}C$ for plastic substrate applications were fabricated and their electrical properties were investigated. Films in ZnO-TFTs with bottom gate configuration were made by RF magnetron sputtering system except for $SiO_2$ gate oxide deposited by ICP-CVD. ZnO channel films were grown on glass with various Ar and $O_2$ flow ratios. All of the fabricated ZnO-TFTs showed perfectly the enhancement mode operation, a high optical transmittance of above 80% in visible ranges of the spectrum. In the ZnO-TFTs with pure Ar process, the field effect mobility, threshold voltage, and on/off ratio were measured to be $1.2\;cm^2/Vs$, 8.5 V, and $5{\times}10^5$, respectively. These characteristic values are much higher than those of the ZnO-TFTs of which ZnO channel layers were processed with additional $O_2$ gas. In addition, ZnO-TFT with pure Af process showed smaller swing voltage of 1.86v/decade compared to those with $Ar+O_2$ process.

• Journal of the Korea Concrete Institute
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• v.24 no.5
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• pp.517-524
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• 2012

In this study, the effects of the inelastic shear behavior of beam-column joint and the vertical distribution of lateral load are evaluated considering higher modes on the response of RC OMRF using the pushover analysis. A structure used for the analysis was a 5-story structure located at site class SB and seismic design category C, which was designed in accordance with KBC2009. Bending moment-curvature relationship for beam and column was identified using fiber model. Also, bending moment-rotation relationship for beam-column joint was calculated using simple and unified joint shear behavior model and moment equilibrium relationship for the joint. The results of pushover analysis showed that, although the rigid beam-column joint overestimated the stiffness and strength of the structure, the inelastic shear behavior of beam-column joint could be neglected in the process of structural design since the average response modification factor satisfied the criteria of KBC2009 for RC OMRF independent to inelastic behavior of joint.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.4
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• pp.31-43
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• 1999

The main goal of this paper is to design a high performance SVP(Stack based Video Processor) for network applications. The SVP is a comprehensive scheme; 'better' in the sense that it is an optimal selection of previously proposed enhancements of a stack machine and a video processor. This can process effectively object-based video data using a S-RISC(Stack-based Reduced Instruction Set Computer) with a semi -general-purpose architecture having a stack buffer for OOP(Object-Oriented Programming) with many small procedures at running programs. And it includes a vector processor that can improve the MPEG coding speed. The vector processor in the SVP can execute advanced mode motion compensation, motion prediction by half pixel and SA-DCT(Shape Adaptive-Discrete Cosine Transform) of MPEG-4. Absolutors and halfers in the vector processor make this architecture extensive to a encoder. We also designed a VLSI stack-oriented video processor using the proposed architecture of stack-oriented video decoding. It was designed with O.5$\mu\textrm{m}$ 3LM standard-cell technology, and has 110K logic gates and 12 Kbits SRAM internal buffer. The operating frequency is 50MHz. This executes algorithms of video decoding for QCIF 15fps(frame per second), maximum rate of VLBV(Very Low Bitrate Video) in MPEG-4.

• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.499-505
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• 2006

Bioventing efficiency was compared in a continuous and an intermittent(6hr injection and 6hr rest) air injection mode. Two lab-scale columns which packed with 5 kg of soil artificially contaminated by diesel oil were operated. The columns were maintained at the $25^{\circ}C{\pm}2.5$ in order to minimize the effect of exterior temperature variation. The flow rate of air injection mode were maintained constantly at the flow rate of 10 ml/min. The moisture of the columns was stably maintained at $60{\sim}80%$ of field capacity. The nutrient compounds were added to make C:N:P ratio as 100:10:l. The continuous and intermittent injection modes showed 67.56% and 69.63% reduction of initial TPH concentration during 90 days, respectively. Two venting modes showed similar results in the analysis of the trends of the hydrocarbon utilizing bacterial counts for operating periods. The carbon dioxide production rate of the continuous injection mode was higher than that of intermittent injection mode. The loss of diesel oil by volatilization in the continuous and intermittent injection modes were about 5% and 1%, respectively. The lower volatilization loss in the intermittent injection mode suggested that the biodegradation of TPH in the intermittent injection mode was greater than that of the continuous mode. These results suggested that the intermittent injection mode is more efficient than the continuous venting mode.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3C
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• pp.175-182
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• 2011

This paper presents a novel eight-parallel 128/256-point mixed-radix multi-path delay commutator (MRMDC) FFT/IFFT processor for orthogonal frequency-division multiplexing (OFDM) systems. The proposed FFT architecture can provide a high throughput rate and low hardware complexity by using an eight-parallel data-path scheme, a modified mixed-radix multi-path delay commutator structure and an efficient scheduling scheme of complex multiplications. The efficient scheduling scheme can reduce the number of complex multipliers at the second stage from 88 to 40. The proposed FFT/IFFT processor has been designed and implemented with the 90nm CMOS technology. The proposed eight-parallel FFT/IFFT processor can provide a throughput rate of up to 27.5Gsample/s at 430MHz.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.2
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• pp.42-47
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• 2014

A finger-gesture game controller using the single camera is implemented in this paper, which is based on the recognition of the number of fingers and the index finger moving direction. Proposed method uses the CAMShift algorithm to trace the end-point of index finger effectively. The number of finger is recognized by using a double circle tracing method. Then, HSI color mode transformation is performed for the CAMShift algorithm, and YCbCr color model is used in the double circle tracing method. Also, all processing tasks are implemented by using the Intel OpenCV library and C++ language. In order to evaluate the performance of the proposed method, we developed a shooting game simulator and validated the proposed method. The proposed method showed the average recognition ratio of more than 90% for each of the game command-mode.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.317-318
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• 1998

The purpose of this study is to design and develop the circuit of the dual mode syringe pump. Syringe pump is used in intensive care unit, delivery room, pediatric room, operating theater and other fields of hospital at present. Normally the syringe pump delivers one medicine in one case, but in case of intensive care unit, it is necessary to deliver more than two kinds of medicines at a time. Therefore we have designed dual mode syringe pump. We used RISC type microcontroller, PIC17C44 as master controller, and PIC16C73 as slave cpu using for the low power consumption. The performance of system is evaluated by analysis of the linearity and accuracy which is the most important factors in application. While the proposed system shows a acceptable linearity and accuracy, a further research about reducing the errorr should be done.

• Journal of Elementary Mathematics Education in Korea
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• v.2 no.1
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• pp.61-80
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• 1998

Whereas research on telelearning in educational technology area is lively done, that in mathematics education area is not. Related to the open education, telelearning has 4 models: the distance classroom model, the front-end system design, the knowledge construction model, and the teaching model based on data. S/W, C/W, and H/W are the components of telelearning system. For an effective mathematics telelearning system, H/W and S/W which use multimedia with complex multimode information such as text, graphics, animation, video, and audio are necessary. Examples of telelearning systems on going are MIPOS, SDS telelearning system, telelearning system of the Naechon Elementary School, and Doorae Multimedia Application Development Platform.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.637-647
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• 1997

As stated in Part(I), the use of the isolator is meant to protect a structure from seismic risk, by concentrating the inelastic deformations to relatively cheap and replaceable devices while the rest of the structures remains elastic. This research has been carried out to investigate the effects of various structural parameters and isolator characteristics on the seismic response of Base Isolated Bridges. Simplified analysis method for practical design is developed by using the results. The Proposed Code-Type approach method can be used to estimate the inertial forces accurately, not only at the isolator but throughout the height of the Base-Isolated Bridges. The proposed method is recommended to use in preliminary design tool or even a final design tool for Base Isolated Bridges. For the validation of simplified design method, examples with artificial earthquake time history and design response spectrum for P.C Box Bridge with bilinear hysteretic steel damper are evaluated.