• Journal of KIISE:Computing Practices and Letters
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• v.16 no.7
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• pp.759-767
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• 2010

RT-eCos 3.0 is a micro-sized embedded real-time kernel that has been developed based on the open source eCos 3.0 to support the basic task model of the well-known distributed real-time object model, TMO(Time-Triggered Message-triggered Object). In this paper, the design and implementation techniques of the RMMC(Real-time Multicast & Memory replication Channel) that is a standard distributed IPC model of the TMO is described based on the RT-eCos 3.0. And the support technique of the global time for using the same time in a distributed environment using the RMMC is also described. The developed global time based RMMC supports highly abstracted distributed IPC environment in a wide area distributed computing environment with the RT-eCos 3.0.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.2
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• pp.102-106
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• 2003

This paper describes novel low-power high-speed flip-flop called dual edge-triggered NAND keeper flip-flop (DETNKFF). The flip-flop achieves substantial power reduction by incorporating dual edge-triggered operation and by eliminating redundant transitions. It also minimizes the data-to-output latency by reducing the height of transistor stack on the critical path. Moreover, DETNKFF allows negative setup time to provide useful attribute of soft clock edge by incorporating the pulse-triggered operation. The proposed flip-flop was designed using a $0.35{\;}\mutextrm{m}$ CMOS technology. The simulation results indicate that, for the typical input switching activity of 0.3, DETNKFF reduces power consumption by as much as 21 %. Latency is also improved by about 6 % as compared to the conventional flip-flop. The improvement of power-delay product is also as much as 25 %.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.9
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• pp.1364-1372
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• 2017

In this paper, a problem of event-triggered model predictive control is investigated for continuous-time Takagi-Sugeno (T-S) fuzzy systems with input quantization. To efficiently utilize network resources, event-trigger is employed, which transmits limited signals satisfying the condition that the measurement of errors is over the ratio of a certain level. Considering sampling and quantization, continuous Takagi-Sugeno (T-S) fuzzy systems are regarded as a sector bounded continuous-time T-S fuzzy systems with input delay. Then, a model predictive controller (MPC) based on parallel distributed compensation (PDC) is designed to optimally stabilize the closed loop systems. The proposed MPC optimize the objective function over infinite horizon, which can be easily calculated and implemented solving linear matrix inequalities (LMIs) for every event-triggered time. The validity and effectiveness are shown that the event triggered MPC can stabilize well the systems with even smaller average sampling rate and limited actuator signal guaranteeing optimal performances through the numerical example.

• Journal of Computing Science and Engineering
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• v.1 no.1
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• pp.56-73
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• 2007

Demands have been growing in safety-critical application fields for producing networked real-time embedded computing (NREC) systems together with acceptable assurances of tight service time bounds (STBs). Here a service time can be defined as the amount of time that the NREC system could take in accepting a request, executing an appropriate service method, and returning a valid result. Enabling systematic composition of large-scale NREC systems with STB certifications has been recognized as a highly desirable goal by the research community for many years. An appealing approach for pursuing such a goal is to establish a hard-real-time (HRT) component model that contains its own STB as an integral part. The TMO (Time-Triggered Message-Triggered Object) programming scheme is one HRT distributed computing (DC) component model established by the first co-author and his collaborators over the past 15 years. The TMO programming scheme has been intended to be an advanced high-level RT DC programming scheme that enables development of NREC systems and validation of tight STBs of such systems with efforts far smaller than those required when any existing lower-level RT DC programming scheme is used. An additional goal is to enable maximum exploitation of concurrency without damaging any major structuring and execution approaches adopted for meeting the first two goals. A number of previously untried program structuring approaches and execution rules were adopted from the early development stage of the TMO scheme. This paper presents new concrete justifications for those approaches and rules, and also discusses new extensions of the TMO scheme intended to enable further exploitation of concurrency in NREC system design and programming.

• The Transactions of the Korea Information Processing Society
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• v.7 no.12
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• pp.3804-3814
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• 2000

This paper presents an efficient implementation of a run-time monitor which checks the satisfaction of the timing constraints of real-time object-oriented programs based on a real-time object model called TMO(Time-triggered Messagedtriggered Object). An execution environment of TMO programs on Windows as, WTMOS(Windows TMO System) has been utilized for the implementation and an experimental application for thermostatic control has been developed to analyze the performance of the run-time monitor. We suggest a methodology for application programmers to specify the target methods with the monitoring conditions and an implementation technique which incurs the small cost by effectively distributing the functions of the monitor into the WTMOS and a TMO object.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10b
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• pp.487-489
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• 1998

원자력 발전소와 같이 환경적으로 큰 재난을 가져 올 수 있는 시스템에서는 전체 시스템을 구축하기 전에 구축하고자 하는 시스템의 안전성을 보장할 수 있는지의 여부와 그러한 시스템의 조작자들의 훈련을 위해 실시간 시뮬레이션이 반드시 필요하다. 본 논문에서는 원자력 발전소의 SIS(Safety Injection System)를 실시간 객체 TMO(Time-triggered Message Triggered Model)를 이용 모델링하는 기법과, 분산 실시간 객체 플랫폼인 WTMOS위에서 구현된 SIS 시뮬레이션 시스템에 대해 기술하였다.

• Journal of the Korean Society of Systems Engineering
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• v.13 no.1
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• pp.1-6
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• 2017

A stores management software which is embedded in the stores management system requires high-level reliability and real-time processing. It also required to implement and verify protocols which requires timing constraints to control various weapons. In this paper, we propose design methodology to design a stores management software and its support middleware based on the TMO (Time-triggered Message-triggered Object) model.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.143-145
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• 1999

정시 서비스를 제공하는 실시간 시스템을 설계할 때 일반성을 지니도록 하기 위하여 실시간 객체인 TMO(Time-triggered Message-triggered Object) 모델이 연구되었으며 이러한 객체를 수행하기 위한 객체 모델 수행 플렛폼이 다양한 환경에서 개발되었다. 본 논문에서는 최근 들어 많은 주목을 받고 있는 리눅스 환경에서 설계 및 구현된 미들웨어 형태의 실시간 객체 모델 수행 플렛폼 LTMOS(Linux TMO System)에 대해 기술한다. 응용 프로그램 개발자가 실시간 시스템을 TMO 모델로 디자인하면 LTMOS는 TMO의 메쏘드를 리눅스의 쓰레드로 매핑하여 리눅스 커널의 실시간 스케쥴링을 받도록 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.226-228
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• 2003

TMO 기반 실시간 이동 정보 생성 시뮬레이터는 적시성이 요구되는 이동 시뮬레이터를 위해 TMO (Time-triggered Message-triggered Object) 모델을 사용하여 적시에 이동 결과를 얻어낼 수 있는 도구이다. 이 TMO 기반 실시간 이동 정보 생성 시뮬레이터는 TMO 모델상에 이동구역을 처리하기 위한 맵 구조와 이동되어질 정보의 이동을 위한 간단한 이동 알고리즘을 내장하고 있다. 본 논문은 이러한 TMO 기반 실시간 이동 정보 생성 시뮬레이터의 구성 및 기능에 관하여 기술한다.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10a
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• pp.566-568
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• 1999

본 논문에서는 실시간 시스템의 시간 제약이 제대로 만족되는가를 시스템 수행 중에 감시하는 수행시간 모니터를 구현하기 위한 환경으로 실시간 객체 모델인 TMO(Time-triggered Message-triggered Object) 모델과 Windows 98NT 상의 TMO 프로그램 실행 환경인 WTMOS(Windows TMO System)를 이용한다. 모니터의 대상과 모니터하는 조건을 TMO 프로그램에 명시하는 방법이 연구되었고 정의된 모니터 기능을 WTMOS 내부와 TMO 형태의 응용 객체로 분산시켜서 적은 비용으로 모니터 시스템을 구축하는 효과적인 방법이 개발되었다.