• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.95-104
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• 2003

The material properties of rubber was determined by the experiments of uniaxial tension, uniaxial compression, planer tension, equi-biaxial tension and volumetric compression. In compression test, it is difficult to obtain the pure state of compression stress and strain due to friction force between the specimen and compression platen. In this study, the stress and strain data from the equi-biaxial tension test were converted to compression stress and strain and compared to a pure state of simple compression data when friction was zero. The compression test device with the tapered platen was proposed to overcome the effect of friction. It was fumed out that the relationship of the stress and strain using the tapered platen was in close agreement with the pure compressive state.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.11
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• pp.581-588
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• 2004

Power qualify monitoring system is devoted to more concern than before, because the innovation of industrial technology needs more accurate instruments and more advanced power quality. This paper was studied on using data of the protective relay by Power Quality Monitor. This paper was proposed the wave storage condition and monitoring clauses of the protective relay as a power quality monitoring device. The protective relay will have problem to save data for PQM analysis because the protective relay memory is limited. Therefore this paper was proposed new a data compression of data got from the protective relay. This method is wave compression comparison algorithm using the DFT. The compression rate is higher than any other established method. This method can be real time storage. This algorithm is verified using the comparison among other compression rate and proved by Real Time Digital Simulator (RTDS).

• IEMEK Journal of Embedded Systems and Applications
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• v.11 no.2
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• pp.79-86
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• 2016

In wireless sensor networks, increasing the sensing rate of each node to improve the data accuracy usually incurs a decrease of network lifetime. In this study, an energy-adaptive data compression scheme is proposed to efficiently control the sensing rate in an energy-harvesting wireless sensor network (WSN). In the proposed scheme, by utilizing the surplus energy effectively for the data compression, each node can increase the sensing rate without any rise of blackout time. Simulation result verifies that the proposed scheme gathers more amount of sensory data per unit time with lower number of blackout nodes than the other compression schemes for WSN.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.5
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• pp.39-54
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• 2012

Picture Archiving and Communication System (PACS) has been planted as one of the key infrastructures with an overall improvement in standards of medical informationization and the stream of digital hospitalization in recent days. The kind and data of digital medical imagery are also increasing rapidly in volume. This trend emphasizes the medical image compression for storing large-scale medical image data. Digital Imaging and Communications in Medicine (DICOM), de facto standard in digital medical imagery, specifies Run Length Encode (RLE), which is the typical lossless data compressing technique, for the medical image compression. However, the RLE is not appropriate approach for medical image data with bilateral symmetry of the human organism. we suggest two preprocessing algorithms that detect interested area, the minimum bounding rectangle, in a medical image to enhance data compression efficiency and that re-code image pixel values to reduce data size according to the symmetry characteristics in the interested area, and also presents an improved image compression technique for brain CT imagery with high bilateral symmetry. As the result of experiment, the suggested approach shows higher data compression ratio than the RLE compression in the DICOM standard without detecting interested area in images.

• Journal of Korea Spatial Information System Society
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• v.7 no.3 s.15
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• pp.45-53
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• 2005

Nowadays, using the mobile communication devices, such as a mobile phone, PDA, telematics device, and so forth, are increasing. The large parts of the services with these mobile devices are the position tracking and the route planning. For offering these services, it is increasing the use of the spatial data on the mobile environment. Although the storage of mobile device expands more than before, it still lacks the necessary storage on the spatial data. In this paper, lossy compression technique on the spatial data is suggested, and then it is analyzed the compression ratio and the amount of loss data by the test. Suggested compression technique on the spatial data at this paper is applied to the real-data, and others methods, suggested at the previous studies, is applied to same data. According as the results from both are compared and analyzed, compression technique suggested at this study shows better performance when the compression result is demanded the high position accuracy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.6
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• pp.515-520
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• 2004

Core-based system-on-a-chip (SoC) designs present a number of test challenges. Two major problems that are becoming increasingly important are long application time during manufacturing test and high volume of test data. Highly efficient compression techniques have been proposed to reduce storage and application time for high volume data by exploiting the repetitive nature of test vectors. This paper proposes a new test data compression technique for SoC testing. In the proposed technique, compression is achieved by partitioning the test vector set and removing repeating segment. This process has $O(n^{-2})$ time complexity for compression with a simple hardware decoding circuitry. It is shown that the efficiency of the proposed compression technique is comparable with sophisticated software compression techniques with the advantage of easy and fast decoding.

• International Journal of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.22-30
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• 2024

Image compression-decompression methods have become increasingly crucial in modern times, facilitating the transfer of high-quality images while minimizing file size and internet traffic. Historically, early image compression relied on rudimentary codecs, aiming to compress and decompress data with minimal loss of image quality. Recently, a novel compression framework leveraging colorization techniques has emerged. These methods, originally developed for infusing grayscale images with color, have found application in image compression, leading to colorization-based coding. Within this framework, the encoder plays a crucial role in automatically extracting representative pixels-referred to as color seeds-and transmitting them to the decoder. The decoder, utilizing colorization methods, reconstructs color information for the remaining pixels based on the transmitted data. In this paper, we propose a novel approach to image compression, wherein we decompose the compression task into grayscale image compression and colorization tasks. Unlike conventional colorization-based coding, our method focuses on the colorization process rather than the extraction of color seeds. Moreover, we employ the Denoising Diffusion Null-Space Model (DDNM) for colorization, ensuring high-quality color restoration and contributing to superior compression rates. Experimental results demonstrate that our method achieves higher-quality decompressed images compared to standard JPEG and JPEG2000 compression schemes, particularly in high compression rate scenarios.

• IEMEK Journal of Embedded Systems and Applications
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• v.7 no.3
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• pp.157-162
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• 2012

In this paper, we propose a flight data storing system for effective data processing. Since the flight data contains critical information and their sizes are vast, encryption and compression would be needed to manage the flight data in effect. And we implemented the flight data storing system using an embedded board with DSP based on DPCM compression and AES encryption. Especially, we applied the reordering technique to advance the security function. From the simulations for two type data of voice and avionics, we found the developed system is well performed.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.425-430
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• 2003

The material properties of rubber was determined by the experiments of uniaxial tension, uniaxial compression, planer tension, equi-biaxial tension and volumetric compression. In compression test, it is difficult to obtain the pure state of compression stress and strain due to friction force between the specimen and compression platen. In this study, the stress and strain data from the equi-biaxial tension test were converted to compression stress and strain and compared to a perfect state of simple compression data when friction was zero. The compression test device with the tapered platen was proposed to overcome the effect of friction. It was turned out that the relationship of the stress and strain using the tapered platen was in close agreement with the pure compressive state.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.8
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• pp.3641-3655
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• 2016

Wireless sensor networks (WSNs) provide a promising approach to monitor the physical environments, to prolong the network lifetime by exploiting the mutual correlation among sensor readings has become a research focus. In this paper, we design a hierarchical network framework which guarantees layered-compression. Meanwhile, a data sorting-based adaptive spatial compression scheme (DS-ASCS) is proposed to explore the spatial correlation among signals. The proposed scheme reduces the amount of data transmissions and alleviates the network congestion. It also obtains high compression performance by sorting original sensor readings and selectively discarding the small coefficients in transformed matrix. Moreover, the compression ratio of this scheme varies according to the correlation among signals and the value of adaptive threshold, so the proposed scheme is adaptive to various deploying environments. Finally, the simulation results show that the energy of sorted data is more concentrated than the unsorted data, and the proposed scheme achieves higher reconstruction precision and compression ratio as compared with other spatial compression schemes.