버스 기반 다중 처리기에서 서브블록 캐쉬의 성능

송인근 우송대학교 부설 산업연구원 1999 산업연구 Vol.1 No.2

In this paper, we measured the performance of the subblock cache protocol, the larger thwe cache block used, the locality of the cache memory is improved. However, the larger cache blocks increase the bus traffic caused by the unneccessary invalidation of the shared cache blocks incurred by the false sharing and its policy of transferring total cache block instead of partial updated parts on the cache block replacement. the subblock cache protocol addresses these problems based on the distinction between the coherence unit and transfer unit. In this paper, we examine an enhanced subblock cache write misses and also having fewer cache line states than existing subblock cache protocols . simulation results show that the suggested subblock protocol improves the perfomance of the simulated parallel programs due to decreased bus traffic.

데이터 병렬 프로그램에서 순차적 선인출 기법

송인근 우송대학교 2000 우송대학교 논문집 Vol.5 No.-

The data prefetching scheme is an effective technique to reduce the main memory access latency by exploiting the overlap of processor computations with data accesses. However, if the prefetched data replicate the useful existing data in the cache memory and they are not being used in computations. performances of programs are aggravated. This phenomenon results from the lack of correct predictions for data being used in the future. When parallel programs exploit the data arrays for computations, the grain size is useful information for data prefetching scheme because in implies the range of data using in computations. Based on this information, we suggest a new data prefetching scheme exploited by the grain size of the parallel program. Simulation results show that the suggested prefetching scheme improves the performance of the simulated parallel programs due to the reduction of bus transactions as well as useful prefetching operations.

성김도 정책에 의한 병렬 프로그램의 성능 평가

송인근 우송대학교 부설 산업연구원 1999 산업연구 Vol.1 No.1

The performance of parallel programs has suffered from the latencies caused by memory access and synchronization. To explore the effect of these latencies, we execute parallel applications varying the scheduling policies and grain sizes. The variations of the memory access patterms generated by the granularity and scheduling policies may affect the cache behavior and synchronization operatioin of the parallel applications. In this paper, the interactions between grain sizes and scheduling policies are examined through execution-driven simulations. The simulatioin results show that the grain size and scheduling policy selected by the programmers have significant impacts on the cache behavior and synchronization latency in most parallel programs. On the basis of the simulation studies, we suggest the best grain size and scheduling policy for each simulated parallel program, and analyze the causes inducing those results.

FSK-주파수 도약 데이터 통신시스템에서의 디지털 주파수 합성기의 영향분석

송인근 한국정보통신학회 2003 한국정보통신학회논문지 Vol.7 No.5

주파수 도약 대역확산시스템에서의 광대역 주파수 도약을 위해 주파수 합성기가 널리 이용된다. 따라서 본 논문에서는 효과적인 무선 디지털 데이터 전송 성능을 얻기 위한 FH-FSK 통신에 미치는 주파수 합성기의 영향을 분석하였다. 이를 위해 PLL의 성능을 좌우하는 위상 변화, 스퓨리어스의 발생, PLL의 과도응답 특성에 의해 영향을 받는 주파수 도약율 등 여러 가지 파라미터들에 따른 성능을 분석하였다. 전형적인 PLL을 사용한 주파수 도약 시스템에서는 주파수 도약을 위한 반송파 신호를 국부 발진기에서 만들어낸다. 반송파 간격이 협대역인 협대역 무선 통신 시스템일 경우에는 빠른 주파수 도약을 위한 PLL의 구현이 어렵다. 본 논문에서는 이런 문제점을 해결하기 위해 디지털 주파수 합성기/CPM 변조기를 사용하여 빠른 주파수 도약을 위한 PLL 구현이 가능함을 Matlab tool를 사용한 시뮬레이션 결과를 통해 분석할 수 있었다. Agile frequency synthesizers are the common device used for commandable, wide-band frequency hopping in frequency-hopped (FH) communications. In this paper, synthesizer phase transient effect and its compensation methods in an FH/FSK(Frequency Hopped Frequency Shift Keying) system are studied. Models for these analysis are developed and resulting performance degradations are computed. The basic PLL is difficult to implement for fast frequency hopping in narrowband radio communication systems. To solve this problem, digital frequency synthesizer/CPM (Continuous Phase Modulation)modulator is proposed. And it's performance is analyzed theoretically. The analysis show that fast frequency hopping is possible in frequency hopping system that use digital frequency synthesizer/CPM modulator.

무선 ATM 네트워크에서의 적응적 Path Rerouting 핸드오버 기법

송인근 우송대학교 산업연구소 2000 산업연구 Vol.2 No.1

Cellular network architecture on the basis of ATM has been improved in Micro/Pico cell type. The frequent path re-establishment in such cell type is occurred by subscriber's mobility. Hence that increases delay time for connection during handover process. In this paper, crossover switch(COS) search algorithm to reduce delay time, the essential part of path rerouting in ATM networks, is proposed. In order to minimize handover delay factor and weighted sum of network resource increasing factor, this thesis proposed and evaluated new COS search algorithm.

MPEG-­4 부호화기를 위한 스트림 생성기 설계

송인근,서기범 한국정보통신학회 2003 한국정보통신학회논문지 Vol.7 No.8

이 논문에서는 MPEG­4를 부호화하기 위한 스트림 생성기의 효율적인 구조 설계에 대하여 제안한다. 이 모듈은 DCT 및 양자화 모듈로부터 출력된 매크로 블록 단위의 양자화 된 계수를 입력으로 하여 부호화 기의 부호화 모드에 따라 VLC 부호화를 수행하며, MPEG­4 의 오류 은익 방법을 지원하며, 데이터 파티션을 지원한다. 이 구조는 VHDL 을 사용하여 설계하였으며, 포스트 시뮬레이션을 통해 설계된 부호화 기의 성능을 평가하였다. In this paper, we propose the architecture of stream producer for MPEG­4 Video encoding. This module receives the quantized coefficient from DCT and Quantization module in macroblock unit and performs the VLC coding according to the encoding mode, and supports the error concealment mode of MPEG­4 and data partitioning mode. Using the VHDL, we designed the module using this architecture and performed the evaluations of this module by performing the post­-simulation.

PCS를 위한 망 구조

송인근 우송대학교 1996 우송대학교 논문집 Vol.1 No.-

본 논문은 개인무선통신에 대한 기능적인 카테고리와 일반적인 개인 통신망에서 호발생시 이동중인 가입자간 연동과정을 나타내었다. 또한 PCS 망에서 계층적 구조 및 분산 구조를 상호 비교하였으며 이를 바탕으로 PCS 망구조 방식을 제안하였다. Personal Telecommunication(PT) is considered to be one of the most attractive telecommunication services in the future. This paper presents the categorization of PT services and various PT services realization schemes for call setup over PT networks. In addition, the characteristics between hierarchical and distributed network architecture for PCS is compared. As the result of this analysis, hierarchical network architecture to provide the efficient PT services is proposed.

토양세균 군집의 대사 다양성과 16S rDNA의 제한효소 지문분석에 의한 유전적 다양성의 비교

송인근,최영길,김유영,조홍범 한국미생물학회 1999 미생물학회지 Vol.35 No.1

BIOLOG GN microplate를 이용한 유일탄소원의 이용능 비교를 통한 대사적 유사성과 16S rDNA 의 PCR 증폭산물의 제한효소 지문 분석에 따른 유전적 유사성을 5종의 식생토양에 따른 토양미생물 군집을 대상으로 비교하였다. 16S rDNA를 증폭하여 제한효소 지문을 분석한 결과, 토양으로부터 직접 추출하여 증폭한 토양세균 군집의 16S rDNA의 유전적 유사도는 BIOLOG GN microplate를 이용한 대사적 구조와 일치하는 경향을 보았다. 그러나 배양된 종속영양세균 군집의 다양성과는 유전적 유사도가 매우 낮게 나타났다. To investigate soil bacterial diversity according to vegelalioo types, utilizing ability of sole carbon sources and restriction enzyme patterns of 16s rDNA were analyzed. From the both results; five kinds of soil microbial communities were grouped as forest soil (Quercus mongolica and Pinus densi&ra vegetation), grass-agricultured soil and microbial communities of naked soil. But, both soil microbial communities of directily exlracted from ths soil and indirectly extracted from heterotrophic bacteria that cultured soil in LB medium showed very different similarity.

참나무과 2종 삼림토양의 환경요인 및 효소활성도 비교분석

송인근,최영길 ( In Geun Song,Yong Keel Choi ) 한국환경생물학회 1997 환경생물 : 환경생물학회지 Vol.15 No.2

Physicochemical environmental factors and enzyme activities were compared between two forest soils in which different species of family Quercoideae were present. Two species are Quercus mongolica and Quercus dentata. Soil pH were ranged 6.2∼6.6 in both forest soils. Moisture content and total organic matter were 1.4 and 1.3 times higher in the surface soil of Q. mongolica forest than the other, repectively. Cellulase activities at the surface soils were 4.71 times and 2.1 times higher than 25㎝ depth soils of Q. mongolica and Q. dentata forest, respectively. Between the surface soil of two vegetational forest, cellulase activity of Q. mongolica forest was 1.69 times than the other. Cellulase activity was correlated with the soluble sugar (R^2=0.623). Protease acitivity was 1.4 times higher in surface soil of Q. mongolica than the other. But, it was 10 fold higher in 25㎝ depth lower soil of Q. dentata forest than Q. mongolica. Phosphatase activities were similar in 25㎝ depth soils of two vegetational forest. But, phosphatase including acidic phosphatase (ACPase), neutral phosphatase (NEPase), alkaline phosphatase (ALPase) showed higher activities in surface soil of Q. mongolica forest compared to Q. dentata forest. Among the 3 kinds of pH dependent phosphatases, ACPase showed close correlationship with protease (R^2= 0.659).

토양 세균 군집의 유일탄소원 이용에 의한 지문분석

송인근,최영길,안영범,신규철,조홍범 한국미생물학회 1999 미생물학회지 Vol.35 No.1

BIOLOG GN microplate를 이용하여 6종의 식생 토양에 따른 토양미생물 군집의 유일탄소원 이용능을 비교 분석하였다. 전체적으로 축합물, 아미노산, 카르복실산 화합물을 잘 이용하였으나, amide의 경우 낮은 이용능을 보였다. 대응분석을 통해 6종류의 식생 토양에 따른 토양미생물 군집은 크게 삼림토양, 초지-경작지토양, 비식생 토양의 3가지 그룹의 대사적 다양성의 차이를 보이는 집단으로 분류되었다. 다차원 척도법 분석을 통해 신갈나무 삼림토양의 미생물 군집은 소나무와 떡갈나무 삼림토양의 미생물 군집과는 또 다른 그룹으로 분리되었다. 이러한 식생토양형에 다른 미생물 군집의 대사 다양성의 차이로 볼 때, 식생의천이에 따라 식생에 영향을 받는 미생물 군집의 대사 다양성 또한 식생의 천이에 대응하여 변화하고 있음을 확인하였다. This study was carried out utilzing ability of sole carbon sources in soil microbial communities used by Biolog GN microplate. Cluster analysis showed that soil microbial cornmuties were categorized into three groups as forest, non-forest soil and naked soil of microbial group. Soil microbial commutites in a forest soil of Qirercus mongoIica was divided into another group microbial communites in Qirercus dendata vegetation soil and Pinus dnzsqlora vegetation soil by Multidimensional scaling(MDS). Generally, sole carbon utilzing abilties were higher in order of polymer, amino acids and carboxylic acids, but it was lower in amides substrates carbon group. From the result: it was supposed that metabolic diversity of microbial communities was corresponded to vegetation succession.