• ETRI Journal
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• v.21 no.4
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• pp.52-64
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• 1999

QoS monitoring is a kind of real-time systems which allows each level of the system to track the ongoing QoS levels achieved by the lower network layers. For these systems, real-time communications between corresponding transport protocol objects is essential for their correct behavior. When two or more entities are employed to perform a certain task as in the case of communication protocols, the capability to do so is called interoperability and considered as the essential aspect of correctness of communication systems. This paper describes a formal approach on modeling and interoperability test case generation of a real-time QoS monitoring protocol. For this, we specify the behavior of flow monitoring of transport layer QoS protocol, i.e., METS protocol, which is proposed to address QoS from an end-to-end's point of view, based on QoS architecture model which includes ATM net work in lower layers. We use a real-time Input/Output finite State Machine to model the behavior of real-time flow monitoring over time. From the modeled real-time I/OFSM, we generate interoperability test cases to check the correctness of METS protocol's flow monitoring behaviors for two end systems. A new approach to efficient interoperability testing is described and the method of interoperability test cases generation is shown with the example of METS protocol's flow monitoring. The current TTCN is not appropriate for testing real-time and multimedia systems. Because test events in TTCN are for message-based system and not for stream-based systems, the real-time in TTCN can only be approximated. This paper also proposes the notation of real-time Abstract Test Suite by means of real-time extension of TTCN. This approach gives the advantages that only a few syntactical changes are necessary, and TTCN and real-time TTCN are compatible. This formal approach on interoperability testing can be applied to the real-time protocols related to IMT-2000, B-ISDN and real-time systems.

• Journal of Institute of Control, Robotics and Systems
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• v.2 no.1
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• pp.60-66
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• 1996

Model Based Predictive Control(MBPC) has been widely used in predictive control since 80's. GPC[1] which is the superset of many MBPC strategies a popular method, but GPC has some weakness, such as insufficient stability analysis, non-applicability to internally unstable systems. However, CRHPC[2] proposed in 1991 overcomes the above limitations. So we chose RHPC based on CRHPC for electric furnace control. An electric furnace which has nonlinear properties and large time delay is difficult to control by linear controller because it needs nearly perfect modelling and optimal gain in case of PID. As a result, those controls are very time-consuming. In this paper, we applied RHPC with equality constraint to electric furnace. The reults of experiments also include the case of RHPC with monotonic weighting improving the transient response and including unmodelled dynamics. So, This paper proved the practical aspect of RHPC for real processes.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.699-704
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• 2004

As being inconvenient to apply reinforced concrete structure to high-rise buildings, it is applied steel structured system. Therefore light-weight wall systems are applied as partition wall to reduce the self-load of the building. But, the required performances of a light-weight wall are not evaluated systematically. As a field survey result, partition walls of house-to-house were not showed their respected performances, so the dwellers are feel so worse the quality of the whole building. In steel-structured high-rise buildings especially, occupant's dissatisfaction concerned indoor noise was high because curtain wall systems having a high air-tight performance isolate the outdoor noise making masking effect. Therefore wall systems which have high performances of sound insulation and air-tightness are required in high-rise buildings. As a result, a new drywall system was presented and the performance was verified with field test.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.855-860
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• 2001

As being inconvenient to apply reinforced concrete structure to high-rise buildings. it is applied steel structured system. Therefore light-weight wall systems are applied as partition wall to reduce the self-load of the building. But. the required performances of a light-weight wall are not evaluated systematically. As a field survey result. partition walls of house-to-house and room-to-room were not showed their respected performances. so the dwellers are feel so worse the quality of the whole building. In steel-structured high-rise buildings especially. occupant's dissatisfaction concerned indoor noise was high because curtain wall systems having a high air-tight performance isolate the outdoor noise making masking effect. Also to suppress indoor air movement. stact effect must be concerned. Therefore wall systems which have high performances of sound insulation and air-tightness are required in high-rise buildings.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.17
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• pp.9-14
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• 1988

A (s, S) inventory policy is studied for a continuous inventory model in which lead times are dependent on the ordering quantity. The model assumes that at most one order is outstanding and demands occur in a compound poison process. The steady-state probability distributions of the inventory levels are derived so as to determine the long-run expected average cost. And the computational procedure is presented.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.4
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• pp.287-295
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• 2014

Smart manufacturing (SM) considered as a new trend of modern manufacturing helps to meet objectives associated with the productivity, quality, cost and competiveness. It is characterized by decentralized, distributed, networked compositions of autonomous systems. The model of SM is inherited from the organization of the living systems in biology and nature such as ant colony, school of fish, bee's foraging behaviors, and so on. In which, the resources of the manufacturing system are considered as biological organisms, which are autonomous entities so that the manufacturing system has the advanced characteristics inspired from biology such as self-adaptation, self-diagnosis, and self-healing. To prove this concept, a cloud machining system is considered as research object in which internet of things and cloud computing are used to integrate, organize and allocate the machining resources. Artificial life tools are used for cooperation among autonomous elements in the cloud machining system.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.1
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• pp.43-50
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• 2020

Many companies around the world are applying CMMI to improve the organization's ability to perform projects, and many others are pushing to obtain CMMI certification as more and more of them are offered as preconditions for participation in projects or supply product. Organizations with high maturity such as CMMI Level 4~5, analyze the accumulated R&D data of the organization and establish the performance management model so that R&D performance is continuously managed. So this paper shows the R&D performance management model made by LIGNex1 which is certificated with CMMI Level 5 organization and the case applied to the project, including its effectiveness.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.5
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• pp.621-626
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• 2003

In this paper, we modeled a virtual life (VL) that reacts to the user s action according to its own behavioral characteristics and grows itself. We established some conditions with which such a VL is designed. Genetic Algorithm is used for the growth process that changes the VL s properties. In this process, the parameter values of the VL s properties are encoded as one chromosome, and the GA operations change this chromosome. The VL s reaction to the user s action is determined by these properties as well as the general expectation of each reaction. These properties are evaluated through 5 fitness measures so as to deal with multi-objective criteria. Here, we present the simulation of the growth Process, and show some experimental results.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.120-124
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• 1991

In this paper, we consider the maneuvering detection and target tracking problem in uncertain linear discrete-time systems. The maneuvering detection is based on X$^{2}$ test[2,71, where Kalman filters have been utilized so far. The target tracking is performed by the maneuvering input compensation based on a maximum likelihood estimator. KF has been known to diverge when some modelling errors exist and fail to detect the maneuvering and to track the target in uncertain systems. Thus this paper adopt the FIR filter[l], which is known to be robust to modelling errors, for maneuvering detection and target tracking problem. Various computer simulations show the superior performance of the FIR filter in this problem.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.132-140
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• 2009

The Cradle(R) is specialized systems engineering tool that developed by 3SL(Structure Software System Limited) that has headquarters in U.K. and U.S.A.. It is recognized as the fastest growing Computer-Aided Systems Engineering Tool(CASE Tool). We built up requirements management database by using Cradle(R) on urban maglev program in Korea. So Cradle(R) provide a network function, is available accesses of clients in external organization that is associated on urban maglev program by the internet. However the network function of Cradle(R) require an opening of some a specific network ports and may causes a decreasing network speed. In this paper, we propose the method to establish an user environment of a requirements management database that overcome constraints on network condition.