• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.713-716
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• 2008

In about the concrete application which recycles Ash the research came to be advanced as research in compliance with researchers relation actively in about cement substitutional concrete mixing ratio and burglar quality of existing. The research which it sees as fundamental research the research which it follows in cement substitutional concrete mixing ratio of existing and it researched different Bottom-Ash recycling qualities in about cup aggregate partial substitution Bottom-Ash application.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.1
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• pp.93-100
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• 2017

Four-stroke cycles in an automobile engine are suction stroke, compression stroke, combustion stroke and exhaustion stroke. A normal operation of engine in compression and power stroke must be processed in optimal fuel-air pressure. In this paper we describe a development of measuring equipment for engine cylinder pressure with observing supply current to self motor(start motor). By comparing the current wave on pressure of the 4 or 6 cylinder in engine, a abnormal cylinder state will be found. The validity of the proposed measuring equipment was shown by experiment for real automobile.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.7
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• pp.1817-1823
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• 1998

V.42bis, a type of LZW(Lempel-Ziv-Welch) code, is well-known as theinter national standard is asynchronous data compression. In this paper, we analyze several undesirable phenomena arising from the application of v.42bis to high speed data transmission, and we propose a modified technique to overcome them. the proposed technique determines the proper size of the dictionary, one of important factors affecting the compression ratio, and improves the method of dictionary generation for a higher compression ratio. Furthermore, we analyze the problem of excessive mode changes and solve it to a certain degree by adjusting the threshold for mode change. By doing this, we can achieve smiller variation of the compression ratio in time. This improvement chtributes to easier and better design and control of the buffer in high speed data transmission.

• Journal of the Korea Institute of Building Construction
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• v.23 no.3
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• pp.231-240
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• 2023

In this research, our goal was to explore the potential use of cement mortar augmented with liquid red mud. To facilitate this, we neutralized liquid red mud(LR) - exhibiting a pH of 10-12 - using sulfuric acid to yield sulfuric acid neutralized red mud(SR). We then evaluated the flow, setting time, and compressive strength of the cement mortar combined with liquid red mud, while also performing a thorough examination of its chemical properties through X-ray diffraction(XRD) and scanning electron microscopy(SEM). The flow tests indicated a decrease in flow values for both MS-LR and MS-SR in comparison to the Plain. Analogously, the setting time for MS-LR and MS-SR was found to be abbreviated when juxtaposed with the Plain. With regards to compressive strength, MS-LR demonstrated a surge in strength at the 1-day mark, while MS-SR displayed a diminution at the 1-day and 3-day timepoints compared to the Plain. XRD analysis illustrated that after 28 days, the XRD patterns of Plain and MS-SR bore significant resemblance, though a new peak was detected in MS-LR. SEM imagery highlighted that the microstructures of Plain and MS-SR were alike, but MS-LR manifested a distinct microstructure, characterized by a finely fibrous formation. Based on these observations, we infer that the replacement of cement mortar with liquid red mud neutralized with sulfuric acid contributes to a noticeable enhancement in strength, thereby verifying its suitability for this application.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.2
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• pp.197-204
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• 2011

RCM is used to clarify the complex phenomena of engine combustion. In order to describe engine combustion, several significant experimental studies are considered. Prediction of the peak pressure is very important since it has a significant influence on engine combustion. In addition, peak-temperature variation can be calculated from the measured peak pressure by using the fundamental thermodynamic relation. When the RCM is in operation, heat transfer occurs through the cylinder wall. Because of this phenomenon, it is difficult to determine the peak pressure without employing the case by case experimental method. The goal of this study is to evaluate the peak pressure analytically. We conduct an experiment to confirm the relationship between the peak pressure and some parameters. Using the results of the peak pressure variation experiment, we develop a general equation that be used to calculate the peak pressure as a function of operation time and compression ratio.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.345-348
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• 2013

This paper provides a method for compression and transmission of on-chip bus data. As the data traffic on on-chip buses is rapidly increasing with enlarged video resolutions, many video processor chips suffer from a lack of bus bandwidth and their IP cores have to wait for a longer time to get a bus grant. In multimedia data such as images and video, the adjacent data signals very often have little or no difference between them. Taking advantage of this point, this paper develops a simple bus data compression method to improve the chip performance and presents its hardware implementation. The method is applied to a Video Codec - 1 (VC-1) decoder chip and reduces the processing time of one macro-block by 13.6% and 10.3% for SD and HD videos, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.124-133
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• 2012

Compressive strength in concrete increases with time. Regression analysis with time is conventionally performed for strength evaluation and prediction. In this study, hydrate amount is assumed as a function of hydration rate and porosity, and modeling on compressive strength is carried out considering decreasing porosity with time, which does not need the regression analysis with time. For twenty one mix proportions of HPC (High Performance Concrete), DUCOM (FE program) which can simulate the behavior in early aged concrete is utilized, and porosity from each mix proportions is obtained with time. For HPC with OPC (Ordinary Portland Cement) concrete, modeling on compressive strength is performed considering hydration rate, unit content of cement, and porosity with time. For HPC with mineral admixtures, a long-term parameter which can handle long-term strength development is additionally considered. From the comparison with the previous test results, the applicability of the proposed model is verified.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.69-75
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• 2012

The study was conducted to determine the effects of adding pig blood as an admixture to both mortar and concrete. The mortar tests included the determination of its unit weight, flow and its compressive strength. Moreover, the concrete test includes the determination of air content, slump, bleeding, setting time compressive strength and freeze-thaw resistance of the material. As the test result, the utilization of pig blood, as an additive to both mortar and concrete mixtures causes air entrainment. The mortar flow increased and both the unit weight and the compressive strength of mortar decreased. As the blood replacement rate increases, the air content decreases over time, the setting and amount of bleeding showed a tendency to decline and reduced compressive strength, and the freeze-thaw resistance of the concrete increased.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.3
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• pp.179-187
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• 2000

Fractal theory has strengths such as high compression rate and fast decoding time in application to image compression, but it suffers from long comparison time necessary for finding an optimally similar domain block in the encoding stage. This paper proposes a neural network based block classifier which enhances the encoding time significantly by classifying domain blocks into 4 patterns and searching only those blocks having the same pattern with the range block to be encoded. Size of a block is differently determined depending on the image complexity of the block. The proposed algorithm has been tested with three different images having various featrues. The experimental results have shown that the proposed algorithm enhances the compression time by 40% on average compared to the conventional fractal encoding algorithms, while maintaining allowable image qualify of PSNR 30 dB.

• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.499-502
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• 2001

Fractal image coding suffers from the long search time of domain pool although it provides many properties including the high compression ratio. We find that the normalized variance of a block is independent of contrast, brightness. Using this observation, we introduce a self similar block searching method employing the d-dimensional nearest neighbor searching. This method takes Ο(log/N) time for searching the self similar domain blocks for each range block where N is the number of domain blocks. PSNR (Peak Signal Noise Ratio) of this method is similar to that of the full search method that requires Ο(N) time for each range block. Moreover, the image quality of this method is independent of the number of edges in the image.