• The KIPS Transactions:PartA
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• v.11A no.7 s.91
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• pp.483-488
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• 2004

For real-time applications, the underlying operating system (0S) should support timeliness guarantees of real-time tasks. However, most of current operating systems do not provide timely management facilities in an efficient way. There could be two approaches to support timely management facilities for real-time applications: (1) by modifying 0S kernel and (2) by Providing a middleware without modifying 0S. In our approach, we adopted the middleware approach based on the TMO (Time-triggerred Message-triggered Object) model which is a well-known real-tine object model. The middleware, named TMSOM (TMO Support Middleware) has been implemented on various OSes such as Linux and Windows XP/NT/98. In this paper, we mainly consider TMOSM implemented on Linux(TMOS/Linux). Although the real-time schedul-ing aIgorithm used in current TMOSM/Linux can produce an efficient real-time schedule, it can be improved for periodic real-time tasks by considering several factors. In this paper, we discuss those factors and propose an improved real-time scheduling algorithm for periodic real-time tasks, In order to simulate the performance of our algorithm, we measure timeliness guarantee rate for periodic real-time tasks. The result shows that the performance of our algorithm is superior to that of existing algorithm. Additionally, the proposed algorithm can improve system performance by making the structure of real-time middleware simpler.

• The Journal of the Korea Contents Association
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• v.16 no.5
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• pp.217-228
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• 2016

Linux it self does not support real-time. To solve this problem RTiK-Linux was designed to support real-time in the kernel space. However, since the user space does not support real-time, it is not easy to develop application. In this paper, we designed and implemented a RTiK-middleware to support real-time in the user space. RTiK-middleware provides real-time scheduling for user space through signal request period after to register process information with request period using apis on application. To evaluate the performance of the proposed RTiK-middleware, we measured the periods of generated real-time threads using RDTSC instructions, and verified that RTiK-middleware operates correctly within the error ranges of 1ms.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.4 s.23
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• pp.58-67
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• 2005

To overcome limitations of test scope, schedule and cost, M&S(Modeling & Simulation) technique has been applied for T&E(Test and Evaluation) of the state-of-art weapon systems. This paper proposes an air defense simulation software framework to reduce both redundancy an[1 programming errors in system simulator. The proposed framework consists of a 'model' and a 'middleware' The 'middleware' is a reliable communication service layer that supports not only HLA(High Level Architecture) which is an international standard in M&S but also TCP/IP, UDP and etc. The main role of 'model' is to schedule and to run the real-time distributed simulation. The proposed framework has been applied to M-SAM(Middle range Surface to Air Missile) system simulator. The proposed framework's scheduling and communication performance results are satisfactory and were measured by hardwired NTP(Network Timer Protocol) time-stamp with GPS(Global Positioning System) timer for better precision.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.98-100
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• 2005

This paper, proposes concept of personal robot middleware core also called streaming layer. Based on openness and portability, the streaming layer is proposed in order to meet requirements of different kinds of applications. The streaming layer architecture provides effective management of data flows and allows integration of different systems with ease regardless software of hardware platform. With extensibility support additional features can be build in without affect to performance. Therefore, heterogeneous network support, real-time communications, embedded boards support can be easily achieved. In order to achieve high performance together with portability into different platforms, the most functions has to be implemented in C language, while critical parts, such as scheduling, priority assignment has to be made using native functions of tested platforms.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4C
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• pp.295-307
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• 2002

The IEEE 1394 protocol is a de facto standard in multimedia digital home network. It supports several advanced features such as hot plugging, dynamic network reconfiguration, isochronous transmission and so on. Since the IEEE 1394 was adapted in the field of multimedia service with QoS guarantee, back bone network protocol with reel-time digital instrumentation and control sub networks, and physical layer protocol for real-time middleware such as real-time CORBA, the additional real-time features has been required in device driver implementation because of the necessity of the predictability enhancement. To guarantee the real-time features, the device driver of the IEEE 1394 should support the priority based packet processing and also need a isochronous buffer management mechanism to deal with the periodic isochronous communication. In this paper, we proposed a new software architecture of the IEEE 1394 device driver for supporting the real-time characteristics such as priority based packet processing, priority based scheduling and so on.

• Journal of Intelligence and Information Systems
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• v.17 no.1
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• pp.1-16
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• 2011

The real-time ubiquitous environment is required to be able to process a series of sensor data within limited time. The whole sensor data processing consists of several phases : getting data out of sensor, acquiring context and responding to users. The ubiquitous computing middleware is aware of the context using the input sensor data and a series of data from database or knowledge-base, makes a decision suitable for the context and shows a response according to the decision. When the real-time ubiquitous environment gets a set of sensor data as its input, it needs to be able to estimate the delay-time of the sensor data considering the available resource and the priority of it for scheduling a series of sensor data. Also the sensor data of higher priority can stop the processing of proceeding sensor data. The research field for such a decision making is not yet vibrant. In this paper, we propose a queuing time computation algorithm for sensor data processing in real-time ubiquitous environment.