• 한국콘텐츠학회논문지
• /
• 제7권12호
• /
• pp.322-332
• /
• 2007

프랙탈의 특성에 알맞은 변형 방법을 고려하였다. IFS 프랙탈에서 점의 위치 특성은 공간적 좌표뿐만 아니라 코드에 의해서도 표현된다. 코드는 프랙탈 내에서의 점의 주소로 볼 수 있는데, 코드값을 바꾸어 생기는 점의 이동에 프랙탈적 특성이 있으므로, 코드의 정보를 이용한 세 가지 변형 방법을 제안하였다. 즉, 한점의 이동에 사용될 벡터로서 1) 코드 변환을 통해 얻어지는 다른 점에서의 벡터장 값을 이용하는 방법과 2) 코드 정보를 활용하여 변위 벡터를 정하는 방법을 구현하여 본 결과, 연속적 변형의 특징과 프랙탈적 특징을 모두 갖는 변형을 얻을 수 있었다. 또한 3) 변형이 가해질 영역을 코드를 활용하여 제한함으로써, 고사리의 경우, 보다 자연물에 적합한 변형을 얻을 수 있었다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제6권4호
• /
• pp.234-239
• /
• 2006

In the past decade, several tools have been developed to automate the floating-point to fixed-point conversion for DSP systems. In the conversion process, a number of scaling shifts are introduced, and they inevitably alter the original code sequence. Recently, we have observed that a compiler can often be adversely affected by this alteration, and consequently fails to generate efficient machine code for its target processor. In this paper, we present an optimization technique that safely migrates scaling shifts to other places within the code so that the compiler can produce better-quality code. We consider our technique to be safe in that it does not introduce new overflows, yet preserving the original SQNR. The experiments on a commercial fixed-point DSP processor exhibit that our technique is effective enough to achieve tangible improvement on code size and speed for a set of benchmarks.

• Nuclear Engineering and Technology
• /
• 제55권6호
• /
• pp.1966-1973
• /
• 2023

Virtual reality technology has been widely used in the field of nuclear and radiation safety, dose rate computing in virtual environment is essential for optimizing radiation protection and planning the work in radioactive-controlled area. Because the CPU-based gamma dose rate computing takes up a large amount of time and computing power for voxelization of volumetric radioactive source, it is inefficient and limited in its applied scope. This study is to develop an efficient gamma dose rate computing code and apply into fast virtual simulation. To improve the computing efficiency of the point kernel algorithm in the reference (Li et al., 2020), we design a GPU-based computing framework for taking full advantage of computing power of virtual engine, propose a novel voxelization algorithm of volumetric radioactive source. According to the framework, we develop the GPPK(GPU-based point kernel gamma dose rate computing) code using GPU programming, to realize the fast dose rate computing in virtual world. The test results show that the GPPK code is play and plug for different scenarios of virtual simulation, has a better performance than CPU-based gamma dose rate computing code, especially on the voxelization of three-dimensional (3D) model. The accuracy of dose rates from the proposed method is in the acceptable range.

• 전자공학회논문지A
• /
• 제29A권3호
• /
• pp.96-105
• /
• 1992

The use of fixed-point digital signal processors, such as the TMS 320C25, requires scaling of data at each arithmetic step to prevent overflows while keeping the accuracy. A software which automatizes this process is developed for TMS 320C25. The programmers use a model of a hypothetical floating-point digital signal processor and a floating-point format for data representation. However, the program and data are automatically translated to a fixed-point version by this software. Thus, the execution speed is not sacrificed. A fixed-point variable has a unique binary-point location, which is dependent on the range of the variable. The range is estimated from the floating-point simulation. The number of shifts needed for arithmetic or data transfer step is determined by the binary-points of the variables associated with the operation. A fixed-point code generator is also developed by using the proposed automatic scaling software. This code generator produces floating-point assembly programs from the specifiations of FIR, IIR, and adaptive transversal filters, then floating-point programs are transformed to fixed-point versions by the automatic scaling software.

• 정보처리학회논문지D
• /
• 제8D권3호
• /
• pp.273-284
• /
• 2001

실제로 사용되는 주소의 분석을 통해 한글주소의 해석방법을 제안하고, 제안한 주소해석 방법을 이용한 주소 검색시스템의 구현에 대하여 서술한다. 주소 상위 및 하위영역의 일치검증을 각각 순차적으로 수행하는 2단계 과정을 통해 최종 배달점에 대한 순로코드를 발생한다. 우편 번호와 주소 상위영역 일치검증 단계에서는 우편버호를 이용하여 주소사전에서 검색된 주소단어와 인식된 문자 후보들과의 비교를 통해 우편 번호를 검증하게 되며, 주소 상위영역과 주소 하위영역이 분리된다. 주소 상위영역 일치검증 과정의 성능향상을 위해 혼동행렬을 제안하고, 주소 인식결과에 혼동행렬을 적용하여 검증 성공률의 향상을 통해 혼동행렬의 유용성을 확인하였다. 주소 하위영역 검증은 번지정보와 건물명 정보를 이용하여 순로코드를 발생하였다. 부분적으로 완성된 광주와 부산지역의 DPF(Delivery Point File)와 레이블링된 데이터를 이용해 분석 가능한 주소에 대해 높은 정확도를 가지고 순로코드를 발생함을 확인할 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권3호
• /
• pp.941-955
• /
• 2015

In dual-channel networks (DCNs), all frequency hopping (FH) sequences used for data channels are chosen from the original FH sequence used for the control channel by shifting different initial phases. As the number of data channels increases, the hitting frequency point problem becomes considerably serious because DCNs is non-orthogonal synchronization network and FH sequences are non-orthogonal. The increasing severity of the hitting frequency point problem consequently reduces the resource utilization efficiency. To solve this problem, we propose a novel hitting frequency point collision avoidance method, which consists of a sequence-selection strategy called sliding correlation (SC) and a collision avoidance strategy called keeping silent on hitting frequency point (KSHF). SC is used to find the optimal phase-shifted FH sequence with the minimum number of hitting frequency points for a new data channel. The hitting frequency points and their locations in this optimal sequence are also derived for KSHF according to SC strategy. In KSHF, the transceivers transmit or receive symbol information not on the hitting frequency point, but on the next frequency point during the next FH period. Analytical and simulation results demonstrate that unlike the traditional method, the proposed method can effectively reduce the number of hitting frequency points and improve the efficiency of the code resource utilization.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
• /
• pp.119-122
• /
• 2000

Recently, many complex DSP (Digital Signal Processing) algorithms have being realized on RISC CPU due to good compilation, low power consumption and large memory space. But, real-time implementation of multiple DSP algorithms on RISC requires the minimum and efficient memory usage and the lower occupancy of CPU. In this thesis, the original floating-point code of MPEG-1 audio decoder is converted to the fixed-point code and then optimized to the efficient assembly code in time-consuming function in accord with RISC feature. Finally, compared with floating-point and fixed-point, about 30 and 3 times speed enhancements are achieved respectively. And 3~4 times memory spaces are spared.

• 대한수학회보
• /
• 제51권4호
• /
• pp.1175-1186
• /
• 2014

We construct new binary optimal self-dual codes of length 50. We develop a construction method for binary self-dual codes with a fixed-point-free automorphism of order 2. Using this method, we find new binary optimal self-dual codes of length 52. From these codes, we obtain Lee-optimal self-dual codes over the ring $\mathbb{F}_2+u\mathbb{F}_2$ of lengths 25 and 26.

• 한국항행학회논문지
• /
• 제16권3호
• /
• pp.488-494
• /
• 2012

본 논문은 악성코드가 사용하는 자기방어기법을 방식에 따라 분류하고, 악의적인 코드를 보호하는 방법의 일종인 패킹에 대해 소개하였으며, 패킹을 이용하는 악성코드를 보다 빠르게 분석할 수 있는 방안을 제시하였다. 패킹기법은 악의적인 코드를 은닉하고 실행 시에 복원하는 기술로서 패킹된 악성코드를 분석하기 위해서는 복원 후의 진입점을 찾는 것이 필요하다. 기존에는 진입점 수집을 위하여 악성코드의 패킹 관련 코드를 자세히 분석하여야만 했다. 그러나 본 논문에서는 이를 대신하여 악성코드를 생성한 표준 라이브러리 코드 일부를 탐색하는 방법을 제시하였다. 제시한 방안을 실제로 구현하여 보다 신속히 분석할 수 있음을 증명하였다.

• International Journal of Internet, Broadcasting and Communication
• /
• 제15권2호
• /
• pp.218-226
• /
• 2023

In Korea, we still use function point based cost estimations for software size and cost of a project. The current problem is that we make difficultly calculating function points with requirements and also have less accurate. That is, it is difficult for non-experts to analyze requirements and calculate function point values with them, and even experts often derive different function points. In addition, all stakeholders strongly make the validity and accuracy of the function point values of the project before /after the development is completed. There are methods for performing function point analysis using source code [1][2][3][4] and some researchers [5][6][7] attempt empirical verification of function points about the estimated cost. There is no research on automatic cost validation with source code after the final development is completed. In this paper, we propose automatically how to calculate Function Points based on natural language requirements before development and prove FP calculation based on the final source code after development. We expect validation by comparing the function scores calculated by forward engineering and reverse engineering methods.