• Journal of KIISE:Software and Applications
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• v.37 no.11
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• pp.851-858
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• 2010

Most mobile devices use a NAND flash memory as their secondary memory. A compressed code of the firmware is stored in the NAND flash memory of mobile devices in order to reduce the size and the loading time of the firmware from the NAND flash memory to a main memory. In order to use a demand paging properly, a compressed code should be decompressed very quickly. The thesis introduces a new dictionary based compression algorithm for the fast decompression. The introduced compression algorithm uses a different method with the current LZ method by storing the "exclusive or" value of the two instructions when the instruction for compression is not equal to the referenced instruction. Therefore, the thesis introduces a new compression format that minimizes the bit operation in order to improve the speed of decompression. The experimental results show that the decoding time is reduced up to 5 times and the compression ratio is improved up to 4% compared to the zlib. Moreover, the proposed compression method with the fast decoding time leads to 10-20% speed up of booting time compared to the booting time of the uncompressed method.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.179-191
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• 2012

In 2003, the US Congress enacted the Code Adam Act of 2003. The Act was so-named in memory of six-year-old Adam Walsh, who was abducted from a Sears department store in Florida and was later found murdered in 1981. According to the Act, the designated authority for a public building must establish procedures for locating a child missing in a federal facility in the USA. In this context, the study basically aims to propose a legislative model for a missing children policy in Korean multi-use facilities, critically analyzing the US Code Adam Act. Unlike the Act, the proposed Korean bill requires all multi-use facilities beyond a certain size, including private buildings, to arrange a feasible missing child procedure on their own premises. The bill can impose an administrative fine on facilities which don't have the procedure in place, and further can make the list of the facilities known to the public. In order to encourage voluntary participation from the private sector, the bill finally suggests the Voluntary Certification Scheme through which participating business can take advantage of the certification logo commercially.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.10B
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• pp.1246-1251
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• 2011

In this paper, BPSK-OFDM-based LED communication systems are applied to watermarking techniques, were studied on how to transfer the additional information data with at the same time as the transfer of LED communication data. For watermarking kasami code was used as spreading codes, and spread additional data is controlled by small signal level to be BPSK-OFDM does not affect the optical signal. BPSK-OFDM is added to an optical signal is transmitted. The performance of the spreading code as a kasami code is autocorrelation of the noise-free environment, under the noise environment was confirmed by autocorrelation. BPSK-OFDM-based LED communication system has been applied proposed technique throughout the simulation in analyzed to BER of BPSK-OFDM DER performance and watermark signal level according to signal size level of data. That was availability confirmed for watermarking data transmit techniques data as being analysis detection performance of watermarking information using LED communication according to the code.

• Corrosion Science and Technology
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• v.3 no.5
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• pp.216-221
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• 2004

The operating experience showed that the fatigue is one of the major piping failure mechanisms in nuclear power plants (NPPs). The pressure and/or temperature loading transients, the vibration, and the mechanical cyclic loading during the plant operation may induce the fatigue failure in the nuclear piping. Recently, many fatigue piping failure occurred at the socket weld area have been widely reported. Many failure cases showed that the gap requirement between the pipe and fitting in the socket weld was not satisfied though the ASME Code Sec. III requires 1/16 inch gap in the socket weld. The ASME Code OM also limits the vibration level of the piping system, but some failure cases showed the limitation was not satisfied during the plant operation. In this paper, the fatigue behavior of the socket weld in the nuclear piping was estimated by using the three dimensional finite element method. The results are as follows. (1) The socket weld is susceptible to the vibration if the vibration levels exceed the requirement in the ASME Code OM. (2) The effect of the pressure or temperature transient load on the socket weld in NPPs is not significant because of the very low frequency of the transient during the plant lifetime operation. (3) 'No gap' is very risky to the socket weld integrity for the specific systems having the vibration condition to exceed the requirement in the ASME OM Code and/or the transient loading condition. (4) The reduction of the weld leg size from $1.09*t_1$ to $0.75*t_1$ can affect severely on the socket weld integrity.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.2
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• pp.103-111
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• 2019

The IoT-driven large-scaled systems consist of connected things with on-chip executable embedded software. These light-weighted embedded things have limited hardware space, especially small size of on-chip flash memory. In addition, on-chip embedded software in flash memory is not easy to update in runtime to equip with latest services in IoT-driven applications. It is becoming important to develop light-weighted IoT devices with various software in the limited on-chip flash memory. The remote instruction execution in cloud via IoT connectivity enables to provide high performance software execution with unlimited software instruction in cloud and low-power streaming of instruction execution in IoT edge devices. In this paper, we propose a Cloud-IoT asymmetric structure for providing high performance instruction execution in cloud, still low power code executable thing in light-weighted IoT edge environment using remote instruction execution. We propose a simulated approach to determine efficient partitioning of software runtime in cloud and IoT edge. We evaluated the instruction cloudification using remote instruction by determining the execution time by the proposed structure. The cloud-connected instruction set simulator is newly introduced to emulate the behavior of the processor. Experimental results of the cloud-IoT connected software execution using remote instruction showed the feasibility of cloudification of on-chip code flash memory. The simulation environment for cloud-connected code execution successfully emulates architectural operations of on-chip flash memory in cloud so that the various software services in IoT can be accelerated and performed in low-power by cloudification of remote instruction execution. The execution time of the program is reduced by 50% and the memory space is reduced by 24% when the cloud-connected code execution is used.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.7
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• pp.956-962
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• 2020

Recently, as the size of data used in an embedded system increases, the need for an ECC decoding operation to robustly receive a massive data is emphasized. In this paper, we propose a method to accelerate the execution of computations that derive syndrome vectors when ECC decoding is performed using Hamming code in an embedded system with a built-in GPU. The proposed acceleration method uses the matrix-vector multiplication of the decoding operation using the CSR format, one of the data structures representing sparse matrix, and is performed in parallel in the CUDA kernel of the GPU. We evaluated the proposed method using a target embedded board with a GPU, and the result shows that the execution time is reduced when ECC decoding operation accelerated based on the GPU than used only CPU.

• Journal of the Korea Society for Simulation
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• v.18 no.3
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• pp.1-11
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• 2009

This paper illustrates a case study of PLC logic simulation in a car manufacturing system. It was developed to simulate and verify PLC control program for automobile panel AS/RS. Because car models become varied, the complexity of supply problem is increasing in the car manufacturing system. To cope with this problem, companies use the AS (automated storage) and RS (retrieval system) but it has logical complexity. Industrial automated process uses PLC code to control the AS/RS, however control information and control codes (PLC code) are difficult to understand. This paper suggests a PLC simulation environment, using 3D models and PLC code with realistic data. Data used in this simulation is based on realistic 3D model and I/O model, using actual size and PLC signals, respectively. The environment is similar to a real factory; users can verify and test the PLC code using this simulation before the implementation of AS/RS. Proposed simulation environment can be used for test run of AS/RS to reduce implementation time and cost.

• Journal of Software Assessment and Valuation
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• v.15 no.1
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• pp.55-62
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• 2019

The needs for small size and low power consumption of information devices is being implemented with SOC technology that implements the program on a single chip in Internet of Thing. Copyright disputes due to piracy are increasing in semiconductor chips as well, arising from disputes in the chip implementation of the design house and chip implementation by the illegal use of the source code. However, since the final chip implementation is made in the design house, it is difficult to protect the copyright. In this paper, we deal with the analysis method for extracting similarity and the criteria for setting similarity judgment in the dispute of source code written in HDL language. Especially, the chip which is manufactured based on the same specification will be divided into the same configuration and the code type.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1152-1157
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• 2004

Temporal behavior of the laser induced incandescence (LII) signal is often used for soot particle sizing, which is possible because the cooling behavior of a laser heated particle is dependent on the particle size. In present study, LII signals of soot particles are modeled using two non-linear coupled differential equations deduced from the energy- and mass-balance of the process. The objective of this study is to see the effects of particle size, laser fluence on soot temperature characteristics and cooling behavior. Together with this, we focus on validating our simulation code by comparing with other previous results. Results of normalized LII signals obtained from various laser fluence conditions showed a good agreement with that of Dalzell and Sarofim's. It could be found that small particles cool faster at a constant laser fluence. And it also could be observed that vaporization is dominant process of heat loss during first 100ns after laser pulse, then heat conduction played most important role while thermal radiation had little influence all the time.

• Journal of Korea Multimedia Society
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• v.14 no.1
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• pp.94-102
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• 2011

To alleviate the size and bandwidth requirement in JPEG2000 system, a new Embedded Compression(EC) algorithm with minor image quality drop is proposed. For both random accessibility and low latency, very simple and efficient hadamard transform based compression algorithm is devised. We reduced LL intermediate memory and code-block memory to about half size and achieved significant memory bandwidth reductions(about 52~73%) through proposed multi-mode algorithms, without requiring any modification in JPEG2000 standard algorithm.