• Journal of Information Processing Systems
• /
• v.15 no.4
• /
• pp.890-903
• /
• 2019

The single carrier frequency domain equalization (SC-FDE) technology is an important part of the broadband wireless access communication system, which can effectively combat the frequency selective fading in the wireless channel. In SC-FDE communication system, the accuracy of timing synchronization directly affects the performance of the SC-FDE system. In this paper, on the basis of Schmidl timing synchronization algorithm a timing synchronization algorithm suitable for FPGA (field programmable gate array) implementation is proposed. In the FPGA implementation of the timing synchronization algorithm, the sliding window accumulation, quantization processing and amplitude reduction techniques are adopted to reduce the complexity in the implementation of FPGA. The simulation results show that the algorithm can effectively realize the timing synchronization function under the condition of reducing computational complexity and hardware overhead.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2001.05a
• /
• pp.175.2-175
• /
• 2001

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.11a
• /
• pp.1037-1041
• /
• 2007

With the advent of sound field simulator, many sound fields have been reproduced by obtaining the impulse responses of specific acoustic spaces like famous concert hall, opera house. This sound field reproduction has been done by the linear convolution operation between the sound input signal and the impulse response of certain acoustic space. However, the conventional finite impulse response based linear convolution operation always makes real-time implementation of sound field generator impossible due to the large amount of computational burden. This paper introduces the fast convolution method using perceptual redundancy in the processed signals, input audio signal and room impulse response. Temporal and spectral psycho-acoustic filters considering masking effects are implemented in the proposed convolution structure. It reduces the computational burden of convolution methods for realtime implementation of a sound field generator. The conventional convolutions are compared with the proposed one in views of computational burden and sound quality. In the proposed method, a considerable reduction in the computational burden was realized with acceptable changes in sound quality.

• Journal of Satellite, Information and Communications
• /
• v.10 no.3
• /
• pp.84-88
• /
• 2015

In this paper, we present that design and implementation of digital extreme-low-frequency (ELF) magnetic meter including wireless monitoring feature. In our lifetime, it is necessary to study how much magnetic field effects to human body. In this paper, we use 3-axis coil-type magnetic sensor, magnetic measurement range is 0.03~10uT and frequency range is 40~180Hz. As magnetic sensor characteristic, frequency loss is occurred that compensated using digital equalize based on DSP processor. Measurement value can be monitored on PC through Wifi communication and measurement error is observed within 6%.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.2
• /
• pp.231-237
• /
• 2008

With the advent of sound field simulator, many sound fields have been reproduced by obtaining the impulse responses of specific acoustic spaces like famous concert hall, opera house. This sound field reproduction has been done by the linear convolution operation between the sound input signal and the impulse response of certain acoustic space. However, the conventional finite impulse response based linear convolution operation always makes real-time implementation of sound field generator impossible due to the large amount of computational burden. This paper introduces the fast convolution method using perceptual redundancy in the processed signals, input audio signal and room impulse response. Temporal and spectral real-time masking blocks are implemented in the proposed convolution structure. It reduces the computational burden of convolution methods for real-time implementation of a sound field generator. The conventional convolutions are compared with the proposed one in views of computational burden and sound quality. In the proposed method, a considerable reduction in the computational burden was realized with acceptable changes in sound quality.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.3
• /
• pp.527-532
• /
• 2021

In this paper, we propose an efficient finite field computation method for Rainbow algorithm, which is the only multivariate quadratic-equation based digital signature among the current US NIST PQC standardization Final List algorithms. Recently, Chou et al. proposed a new efficient implementation method for Rainbow on the Cortex-M4 environment. This paper proposes a new multiplication method over the finite field that can reduce the number of XOR operations by more than 13.7% compared to the Chou et al. method. In addition, a multiplicative inversion over that can be performed by a 4x4 matrix inverse instead of the table lookup method is presented. In addition, the performance is measured by porting the software to which the new method was applied onto RaspberryPI 3B+.

• Asia pacific journal of information systems
• /
• v.4 no.2
• /
• pp.247-263
• /
• 1994

This paper reports the results of a field study investigating the effect of user participation and attitude on the success of information system implementation during the system development process. The theoretical framework for this research is based on the organizational change theory, in which the attitude affects the effects of user's participation. User participation and attitude were defined as independent variables and the performance of system implementation as dependent variable. User participation was defined as a direct participation by end users in the process of the new information system development. This was measured by user's participation/non-participation. User attitude refers to user's opinions or feelings before a new system is developed. This was measured by user's favor toward a system. The performance of system implementation was measured by the surrogate variable, the degree of individual satisfaction on developed system. To achieve the objective of this research, a field research method utilizing questionnaires were employed. They were distributed to 221 users present during and/or after system development. Among 185 questionnaires returned, 175 questionnaires were used for analysis. The major findings can be summarized as follows: First, there was no significant effect of user participation on user satisfaction. Second, there was a significant effect of user attitude on user satisfaction. Third, there was no significant interaction effect of user participation and attitude on user satisfaction. It is worth to note that the user's participation did not have any significant effect on the user's satisfaction. It seems the reason for the above result is due to user's involuntary participation. In fact, the user does not have much leverage in the process of system development, which may result in poor performance of user participation. Since user attitude is an important factor in the success of system implementation, however, a method to overcome unfavorable attitude of user should proceed all others.

• Journal of Korean Society of Rural Planning
• /
• v.23 no.2
• /
• pp.19-28
• /
• 2017

While the significance and need of landscape assessment for rural area has been recognised, an appropriate method has not been established due to the lack of statutory ground and policy status in Korea. For that reason, current studies have been limited to dominantly amenity field survey in specific rural areas and stayed in academic. In particular, the majority of research on rural landscape amenity or character assessment methodologies so far has been attempted with quantitative processes. Such quantitative methods produced sometimes, heavily overlapped, conflicted, and not much meaningful characterisation and classification. Moreover, such results could not only have been reflected to policy implementation but provide vision for rural areas. Therefore, this study offers new facets for landscape character assessment methods through the lens of practitioners' qualitative survey methods and moreover, seek a policy implementation of newly developed methodologies. In order to carry out such analysis, the study employed a case study of England's Landscape Character Assessment and survey location was Gateshead Council, Northeast of England. The study suggests meaningful qualitative landscape character assessment method and review of its policy implementation.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.4
• /
• pp.1655-1666
• /
• 2015

This paper proposes a new approach of Field Programmable Gate Array (FPGA) controlled digital implementation of shunt active power filter (SAPF) under steady state and dynamic operations. Typical implementations of SAPF uses microprocessor and digital signal processor (DSP) but it limited for complex algorithm structure, absence of feedback loop delays and their cost can be exceed the benefit they bring. In this paper, the hardware resources of an FPGA are configured and implemented in order to overcome conventional microcontroller or digital signal processor implementations. This proposed FPGA digital implementation scheme has very less execution time and boosts the overall performance of the system. The FPGA controller integrates the entire control algorithm of an SAPF, including synchronous reference frame transformation, phase locked loop, low pass filter and inverter current controller etc. All these required algorithms are implemented with a single all-on chip FPGA module which provides freedom to reconfigure for any other applications. The entire algorithm is coded, processed and simulated using Xilinx 12.1 ISE suite to estimate the advantages of the proposed system. The coded algorithm is also defused on a single all-on-chip Xilinx Spartan 3A DSP-XC3SD1800 laboratory prototype and experimental results thus obtained match with simulated counterparts under the dynamic state and steady state operating conditions.

• Journal of information and communication convergence engineering
• /
• v.15 no.2
• /
• pp.97-103
• /
• 2017

Implementation of faster pairing calculation is the basis of efficient pairing-based cryptographic protocol implementation. Generally, pairing is a costly operation carried out over the extension field of degree $k{\geq}12$. But the twist property of the pairing friendly curve allows us to calculate pairing over the sub-field twisted curve, where the extension degree becomes k/d and twist degree d = 2, 3, 4, 6. The calculation cost is reduced substantially by twisting but it makes the discrete logarithm problem easier if the curve parameters are not carefully chosen. Therefore, this paper considers the most recent parameters setting presented by Barbulescu and Duquesne [1] for pairing-based cryptography; that are secure enough for 128-bit security level; to explicitly show the quartic twist (d = 4) and sextic twist (d = 6) mapping between the isomorphic rational point groups for KSS (Kachisa-Schaefer-Scott) curve of embedding degree k = 16 and k = 18, receptively. This paper also evaluates the performance enhancement of the obtained twisted mapping by comparing the elliptic curve scalar multiplications.