OpenCL을 활용한 CPU와 GPU 에서의 CMMB LDPC 복호기 병렬화

박주열,홍정현,정기석,Park, Joo-Yul,Hong, Jung-Hyun,Chung, Ki-Seok 대한임베디드공학회 2016 대한임베디드공학회논문지 Vol.11 No.6

Recently, Open Computing Language (OpenCL) has been proposed to provide a framework that supports heterogeneous computing platforms. By using an OpenCL framework, digital communication systems can support various protocols in a unified computing environment to achieve both high portability and high performance. This article introduces a parallel software decoder of Low Density Parity Check (LDPC) codes for China Multimedia Mobile Broadcasting (CMMB) on a heterogeneous platform. Each step of LDPC decoding has different parallelization characteristics. In this paper, steps suitable for task-level parallelization are executed on the CPU, and steps suitable for data-level parallelization are processed by the GPU. To improve the performance of the proposed OpenCL kernels for LDPC decoding operations, explicit thread scheduling, loop-unrolling, and effective data transfer techniques are applied. The proposed LDPC decoder achieves high performance by using heterogeneous multi-core processors on a unified computing framework.

SNR 예측 정보 기반 적응형 Modified UMP-BP LDPC 복호기 설계

박주열,조걸,정기석,Park, Joo-Yul,Cho, Keol,Chung, Ki-Seok 대한임베디드공학회 2009 대한임베디드공학회논문지 Vol.4 No.4

As 4G mobile communication systems require high transmission rates with reliability, the need for efficient error correcting code is increasing. In this paper, a novel LDPC (Low Density Parity Check) decoder is introduced. The LDPC code is one of the most popular error correcting codes. In order to improve performance of the LDPC decoder, we use SNR (Signal-to-Noise Ratio) estimation results to adjust coefficients of modified UMP-BP (Uniformly Most Probable Belief Propagation) algorithm which is one of widely-used LDPC decoding algorithms. An advantage of Modified UMP-BP is that it is amenable to implement in hardware. We generate the optimal values by simulation for various SNRs and coefficients, and the values are stored in a look-up table. The proposed decoder decides coefficients of the modified UMP-BP based on SNR information. The simulation results show that the BER (Bit Error Rate) performance of the proposed LDPC decoder is better than an LDPC decoder using a conventional modified UMP-BP.

대구도시철도 1호선 전동차 ATP/ATO System 개량 연구

박주열(J. Y. Park),김효상(H. S. Kim),진병삼(B. S. Jin),박재완(J. Y. Park),김봉택(B. T. Kim),이준환(J. H. Lee) 한국도시철도학회 2015 한국도시철도학회논문집 Vol.3 No.2

On-Board Signaling equipment for the rail car is similar as a nerve network of human body which needs high reliability and stability. Daegu metro line 1 was opened to the public on July 1997 and it is providing reliable and stable large-scale transportation for the Daegu citizens up to the present. But, for 18 years of long operation, equipments are being obsolete and it is now facing several problems on maintaining and repairing the product because spare parts of the equipments are no longer manufactured. Specially, ATP/ATO train signaling equipments of Daegu metro line 1 needs to have continuous support and functional upgrade because of relatively long runtime and unstable running environment which is different from ground signaling equipment. In this paper we have improved the difficulties of analysing and preventing recurrence of malfunction on the ordinary train signaling equipment which is unable to save and view the processing information data because limitations of circuit organization and usage of supplier"s hardware & software

『서예학연구』 20년, 그 연구 성과와 성찰

박주열(Park, Ju-yeol) 한국서예학회 2020 서예학연구 Vol.36 No.-

본 연구는 한국서예학회가 창립된 지 20년이 넘은 시점에서 그간 발행한 논문들을 분류·분석하여 연구된 논문의 연구대상과 연구동향을 파악하고 이를 통해 앞으로 한국 서예학이 나아가야할 방향을 모색하는 것에 목적이 있다. 한국서예학회에서 발행하는 학술지 『서예학연구』는 제35호(2019.9.28. 발간)까지 발간되었다. 2000년 5월 창간호가 발간된 이래로 총 36권의 학술지가 발간되었고, 수록된 논문은 총388편이며, 게재한 연구자의 수는 176명이다. 그간 연구된 논문의 연구대상과 연구동향을 파악하여, 이를 통해 앞으로 한국 서예학이 나아가야할 방향을 찾고자 하였다. 그 결과는 다음과 같다. 첫째로, 한글서예에 대한 연구를 확대할 필요가 있다. 다양한 연구자가 관심을 가지고 참여하여 새로운 시각으로 한글서예를 조명할 필요성이 있다. 둘째는 근·현대 서예에 대한 연구가 필요하다. 근대는 과거와 현대를 이어주는 중요한 시기이므로 이 분야에 대한 연구를 확대하다 보면 현대 사회에서 서예와 서예학이 나아가야할 방향성을 찾을 수 있을 것이다. 셋째로, 서예 교육에 대한 연구가 필요하다. 이를 통해 서예의 가치와 서예 교육의 의의가 제대로 정립되어야 한다. 『서예학연구』에 게재된 논문만을 연구대상으로 삼았기 때문에 학위논문이나 기타 연구소 등의 다양한 연구들을 포함시키지는 못했다. 그러나 388편의 적지 않은 논문을 분류·분석하여 서예학 연구의 발전을 도모하고자 했다는 점에서 이 연구는 의의가 있으며, 이 연구에서 결론지은 제언이 한국 서예학의 발전에 일말의 도움이 되기를 바란다. This study was intended to identify the research subjects and research trend of the published papers and to seek the direction for Korean calligraphy studies to develop by classifying and analyzing the published papers for 20 years since the founding of the Korean Society of Calligraphy. The Study of Calligraphy, published by the Korean Society of Calligraphy, was published until No. 35 (published on Aug. 28, 201). Since the publication of the first issue in May 2000, a total of 36 journals have been published. The number of published papers is 388, and the number of authors is 176. By grasping the research subjects and research trend of the published papers so far, through this, I tried to find the direction for Korean calligraphy to develop, and the results are as follow. First, it is necessary to expand the research on Hangeul calligraphy. There is a need to study Hangeul calligraphy from a new perspective with various researchers participating with interest. Second, studies on the modern and contemporary calligraphy are needed. The modern period is an important time connecting the past and now, so if you expand your research in this field, you will find the direction that calligraphy and calligraphy studies should develop in modern society. Third, it is necessary to study calligraphy education. Through this, the value of calligraphy and the significance of calligraphy education should be properly established. Since only the papers published in The Study of Calligraphy were targeted for this study, it did not include dissertations of Universities and various studies from the calligraphy research institutes. However, this study is still significant in that it attempted to promote the development of calligraphy studies by classifying and analyzing 388 papers, and I hope that the suggestion I concluded in this study will help in the development of Korean calligraphy study.

서위(徐渭)의 이단적(異端的) 서예심미의식(書藝審美意識) 고찰(考察)

박주열 ( Park Juyeol ) 한국동양예술학회 2018 동양예술 Vol.40 No.-

XuWei(徐渭, 1521∼1593) was a talented man who has made various achievements in various fields of art such as poetry, drama, calligraphy and paintings. In the middle and late period of Ming Dynasty, when XuWei has lived, it was confused in the political, social, and economic aspects, and the signs of innovation were shown in each field. He was one of the progressive intellectuals who led the transformation in keeping with the change of the times. In this study, I focused on XuWei who did not afraid of change and established the ingenious art world, and examined his heretical aesthetic consciousness of calligraphy against the trend of the times. XuWei pointed out the evils of the field of literature of the times, such as the retroism and the pseudoclassicism, and argued that the art should reflect the times. He sought to find an alternative to overcome the evils of this retroism in ‘emotion’. His mind was full of wrath and frustration about the absurdity and corruption of society, and he was able to express himself through art. Thus, his poetry revealed a critical awareness of the contradictions of society. His critical consciousness, which emphasized emotion, ultimately manifested itself as an aesthetic consciousness recognizing individuality. Natural Attainment(天成) he emphasized was not the absolute value that applied to everyone, but was to show their own energies. As such, his literary view, critical consciousness, and aesthetic consciousness were all contradictory at the time. If the trend of the times was orthodoxy, all his thoughts and actions were heresy. No matter whether such actions began with a complaint about society or a lamentation about his own situation, he created a big wind of change in the art world of literature, calligraphy and paintings. The fact that he did not afraid of change and pursued it deserves to be highly appreciated even in the present age.

원전 케이블의 열적 손상에 관한 실험적 연구

박주열(Ju-Yeol Park),문선여(Sun-Yeo Mun),조재호(Jae-Ho Cho),황철홍(Cheol-Hong Hwang) 한국화재소방학회 2023 한국화재소방학회 학술대회 논문집 Vol.2023 No.1

언어 변환을 위한 설계 방법

박주열(Ju-Yeol Park),곽동규(Dong-Guy Kawk),고방원(Bang-Won Ko),유재우(Chae-Woo Yoo) 한국정보과학회 2008 한국정보과학회 학술발표논문집 Vol.35 No.1

현재 컴퓨터 응용프로그램을 개발하기 위해 많은 프로그래밍 언어가 존재한다. 사용자는 사용 목적에 따라 그에 맞는 새로운 프로그래밍 언어를 학습하고 사용한다. 그러나 프로그래밍 언어를 학습하고 사용하기 위해서는 많은 시간과 노력이 필요하기 때문에 사용자의 언어 학습의 비용과 시간을 줄이기 위해 두 언어간에 변환을 가능하게 해주는 방법이 필요하다. 본 논문에서는 기존의 어휘 분석, 구문 분석 등의 여러 단계를 거치는 방법과는 다른 토큰 매핑 테이블과 XML로 기술한 변환 규칙을 통한 새로운 언어변환을 위한 설계 방법을 제시함으로써 재사용성과 생산성을 높일 수 있는 것으로 기대된다.

Mg다이캐스팅에서 사출조건 변화가 자동차 차체부품 품질에 미치는 영향

박주열(Jooyul Park),김용현(Yonghyun Kim) 한국자동차공학회 2013 한국자동차공학회 부문종합 학술대회 Vol.2013 No.5

철도신호를 위한 단일칩 개발에 관한 연구

박주열(Park Joo-Yul),김효상(Kim Hyo-Sang),이준환(Lee Joon-Hwan),김봉택(Kim Bong-Taek),정기석(Chung Ki-Seok) 한국철도학회 2008 한국철도학회 학술발표대회논문집 Vol.- No.-

As the railway transportation is getting faster and its operation speed has increased rapidly, its signal control has been complicated. For real time signal processing it is very important to prohibit any critical error from causing the system to malfunction. Therefore, handling complicated signals effectively while maintaining fault-tolerance capability is highly expected in modern railway transportation industry. In this paper, we suggest an SoC (Sytem-on-Chip) design method to integrate these complicated signal controlling mechanism with fault tolerant capability in a single chip. We propose an SoC solution which contains a high performance 32-bit embedded processor, digital filters and a PWM unit inside a single chip to implement ATO"s, ATC"s, ATP"s and ATS"s digital signal-processing units. We achieve an enhanced reliability against the calculation error by adding fault tolerance features to ensure the stability of each module.

메모리 사용을 최적화한 부분 병렬화 구조의 CMMB 표준지원 LDPC 복호기 설계

박주열(Joo-Yul Park),이소진(So-Jin Lee),정기석(Ki-Seok Chung),조성민(Seong-Min Cho),하진석(Jin-Seok Ha),송용호(Yong-Ho Song) 大韓電子工學會 2011 전자공학회논문지SD (Semiconductor and devices) Vol.48 No.1

본 논문에서는 CMMB (China Mobile Multimedia Broadcasting) 표준의 LDPC(Low Density Parity Check) 부호 복호기를 효과적으로 구현하는 방법을 제안한다. 본 논문은 AGU(Address Generation Unit)와 Index 행렬을 이용하여 효율적으로 주소 값을 생성함으로써, 메모리 사용량을 줄이고 복잡도를 감소시켰다. 또한 LDPC 부호 복호기의 throughput을 향상시키기 위해 한 클럭에 여러 메시지를 전달하는 부분 병렬 구조를 사용하였고, 하나의 주소를 사용하여 병렬적으로 동작이 가능하도록 노드 그룹핑을 진행하였다. 제안하는 LDPC 부호 복호기는 Verilog HDL로 구현하였으며, Synopsys사의 Design Compiler를 이용하여 Chartered 0.18㎛ CMOS cell library 공정으로 합성하였다. 제안된 복호기는 455K(in NAND2)의 크기를 가지며, 185MHz의 클럭에서 1/2 부호는 14.32 Mbps의 throughput을 갖고, 3/4 부호는 26.97Mbps의 throughput을 갖는다. 또한, 기존의 CMMB용 LDPC의 메모리와 비교하여 0.39% 의 메모리만 사용된다. In this paper, we propose a memory efficient multi-rate Low Density Parity Check (LDPC) decoder for China Mobile Multimedia Broadcasting (CMMB). We find the best trade-off between the performance and the circuit area by designing a partially parallel decoder which is capable of passing multiple messages in parallel. By designing an efficient address generation unit (AGU) with an index matrix, we could reduce both the amount of memory requirement and the complexity of computation. The proposed regular LDPC decoder was designed in Verilog HDL and was synthesized by Synopsys’ Design Compiler using Chartered 0.18㎛ CMOS cell library. The synthesized design has the gate size of 455K (in NAND2). For the two code rates supported by CMMB, the rate-1/2 decoder has a throughput of 14.32 Mbps, and the rate-3/4 decoder has a throughput of 26.97 Mbps. Compared with a conventional LDPC for CMMB, our proposed design requires only 0.39% of the memory.