Soonhoi Ha
서울대학교 컴퓨터공학부 · 컴퓨터과학
Soonhoi Ha 교수의 연구실은 하드웨어/소프트웨어 공동설계(HW-SW codesign) 분야에서 주로 활동하며, 실시간 제약 조건을 갖는 멀티미디어 애플리케이션을 대상으로 하이브리드 모델 기반의 설계 환경을 개발하고 있습니다. 데이터플로우 기반의 스케줄링 기법, 컴파일 타임 최적화, 그리고 기능 시뮬레이션에서 시스템 합성에 이르는 원스톱 설계 플로우를 구현한 Peace 및 PeaCE와 같은 코드esign 환경을 핵심 연구 과제로 삼고 있습니다. 특히, 실시간성과 자원 효율성을 동시에 확보하기 위한 동적 반복 구조 처리 및 스케줄링 전략 최적화에 초점을 맞추고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Existent hardware-software (HW-SW) codesign tools mainly focus on HW-SW cosimulation to build a virtual prototyping environment that enables software design and system verification without need of making a hardware prototype. Not only HW-SW cosimulation, but also HW-SW codesign methodology involves system specification, functional simulation, design-space exploration, and hardware-software cosynthesis. The PeaCE codesign environment is the first full-fledged HW-SW codesign environment that provi
Four scheduling strategies for dataflow graphs onto parallel processors are classified: (1) fully dynamic, (2) static-assignment, (3) self-timed, and (4) fully static. Scheduling techniques valid for strategies (2), (3), and (4) are proposed. The focus is on dataflow graphs representing data-dependent iteration. A known probability mass function for the number of cycles in the data-dependent iteration is assumed, and how a compile-time decision about assignment and/or ordering as well as timing
Scheduling dataflow graphs onto processors consists of assigning actors to processors, ordering their execution within the processors, and specifying their firing time. While all scheduling decisions can be made at runtime, the overhead is excessive for most real systems. To reduce this overhead, compile-time decisions can be made for assigning and/or ordering actors on processors. Compile-time decisions are based on known profiles available for each actor at compile time. The profile of an acto
Hardware/software codesign involves various design problems including system specification, design space exploration, hardware/software co-verification, and system synthesis. A codesign environment is a software tool that facilitates capabilities to solve these design problems. This paper presents the peace codesign environment mainly targeting for multimedia applications with real-time constraints. Peace specifies the system behavior with a heterogeneous composition of three models of computati
A noble model-based programming environment of embedded software for MPSoC is proposed. By defining a common intermediate code (CIC), it separates modeling of the software and implementation optimized for target architecture. It also allows us to use diverse models for initial specification. Another feature is to provide multi-phase debugging capabilities: at the modeling stage, at the code generation stage, and at the simulation stage. Preliminary experiments with a Divx player confirm the feas
Scheduling of dataflow graphs onto parallel processors consists of assigning actors to processors, ordering the execution of actors within each processor, and firing the actors at particular times. Many scheduling strategies do at least one of these operations at compile time to reduce run-time cost of scheduling activities. In this thesis, we classify four scheduling strategies, (1) fully dynamic, (2) static-assignment, (3) self-timed, and (4) fully static. These are ordered in decreasing run-t
Scheduling strategies for a multiprocessor DSP (digital signal processor) are classified into four types: fully dynamic, static-assignment, self-timed, and fully static. The concept of static scheduling (self-timed or fully static) is extended to handle nondeterministic actors in the proposed quasi-static scheduling. Quasi-static scheduling minimizes run-time overhead with increased compilation complexity, and is thus adequate for signal processing applications. The proposed scheme is applicable
On behalf of the CODES+ISSS 2007 Organizing and Program Committees, we would like to welcome you to the 5th IEEE/ACM International Conference on Hardware/Software Co-Design and System Synthesis. CODES+ISSS is the premier conference for system-level design, with a focus on the design of embedded systems hardware, software, and tools. This year we continue the tradition of maintaining a high-quality forum for active discussion on current and innovative topics on embedded systems that bring toge