• Journal of Information Processing Systems
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• 제15권4호
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• pp.890-903
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• 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.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.175.2-175
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• 2001

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1037-1041
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• 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.

• 한국위성정보통신학회논문지
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• 제10권3호
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• pp.84-88
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• 2015

본 논문은 극저주파 자계 세기를 무선 모니터링하기 위한 디지털 자계측정기의 설계 및 구현에 대해 기술한다. 우리 실생활에 극 저주파대역의 자기장이 노출되어 있어 인체에 자기장이 얼마나 영향을 미치는가에 대한 연구의 필요성이 있으며 그에 따른 측정 장비의 수요가 증가하고 있다. 본 논문에서는 3-축 코일형 자계센서를 사용하였으며, 자계의 측정 범위는 0.03~10uT, 주파수 범위는 40~180Hz이다. 자계 세기의 측정과 주파수 특성을 보상하는 등화기능은 DSP 기반의 디지털 방식으로 설계하였으며, 측정 값은 와이파이 통신을 이용하여 PC 모니터링 할 수 있도록 설계 및 구현하였고 측정오차는 6% 이내로 실용성을 확인하였다.

• 한국소음진동공학회논문집
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• 제18권2호
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• pp.231-237
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• 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.

• 정보보호학회논문지
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• 제31권3호
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• pp.527-532
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• 2021

본 논문에서는 미국 NIST PQC 표준화 Final List 알고리즘 중 유일한 다변수이차방정식(multivariate quadratic equation) 기반의 전자 서명인 Rainbow 알고리즘에서의 효율적인 유한체 연산 방법을 제안한다. Chou 등은 최근 Rainbow를 Cortex-M4에서 구현하기 위한 새로운 효율적 구현 방법을 제시하였다. 본 논문은 Chou 등이 제안한 방법을 개선하여 기존 대비 XOR 연산의 숫자를 13.7% 이상 감소할 수 있는 새로운 곱셈 방법을 제안한다. 또한, 테이블 룩업(Table Lookup)으로 수행되던 상에서의 역원 연산을 4x4 행렬 역원으로 치환하여 연산하는 방법을 제시한다. 또한, 새로운 구현을 RaspberryPI 3B+상에서 구현하여 성능을 측정하였다.

• 사물인터넷융복합논문지
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• 제10권3호
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• pp.1-6
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• 2024

산업계를 중심으로 최근에는 위치에 구애받지 않고 다양한 서비스를 자유롭게 이용하고자 하는 수요가 급증하면서, 비용 효율적이고 구축이 용이한 wireless mesh network (WMN) 솔루션이 다시 주목받고 있다. 본 논문에서는 3차원 WMN을 위한 라우팅 솔루션인 Autonomous Load-balancing Field-based Anycast routing+ (ALFA++)의 구현 이슈를 심도 있게 살펴본다. 이후에는 저가 상용 장치를 활용하여 구축한 대학 캠퍼스 건물 내 802.11 기반 3차원 WMN 테스트베드에서 ALFA+의 성능을 평가하고 이를 통해 궁극적으로 ALFA+의 실제 활용 가능성을 검증한다. 기존 대부분의 연구는 가상환경 기반 시뮬레이션을 통한 성능평가를 한 반면, 본 연구에서는 실환경 테스트베드에서 상용 장치를 활용한 성능평가 수행을 위해 필요한 구현 관련 상세정보를 소개하고 실환경 테스트베드에서의 결과를 기반으로 ALFA+의 실질적인 가치를 평가했다는 점에서 큰 의미가 있다.

• Asia pacific journal of information systems
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• 제4권2호
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• pp.247-263
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• 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.

• 농촌계획
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• 제23권2호
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• pp.19-28
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• 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
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• 제10권4호
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• pp.1655-1666
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• 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.