• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.126-130
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• 2006

Programmable Logic Controller(PLC) is the most widely utilized and plays an important role in industrial control system. Sequential Function Chart(SFC) is a graphic language which is suitable for describing a sequential control logic in discrete control system. We can design a distribute control construction and a hierarchical control construction in process control system described by SFC. In hierarchical control structure, we construct each subsystems to synchronize a synchronous signal between subsystems, and the command system gives and takes a synchronous signal with subsystems. Therefore, the system has a low memory efficiency and a low system performance. In this paper, we propose the method that improved the efficiency of memory in hierarchical control construction, and confirm its feasibility through an actual example.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.35-42
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• 2021

The college English teaching-learning model in this study is intended to effectively apply dictogloss activities to enhance competencies such as communication, self-directedness, and cooperation by upgrading the utilization of various online platform functions. Dictogloss is a language teaching and learning activity that combines four functions (listening, speaking, reading, and writing) of communication. College English classes in this study focus on communication-oriented integrated English education. In this study, the teaching and learning is an online-based English integrated teaching-learning method based on constructivism theory. The model presented the roles of learners and teachers according to the seven procedures.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1423-1433
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• 2018

Recently, a permanent magnet synchronous motor of middle and small-capacity has high torque, high precision control and acceleration / deceleration characteristics. But existing control has several problems that include unpredictable disturbances and parameter changes in the high accuracy and rigidity control industry or nonlinear dynamic characteristics not considered in the driving part. In addition, in the drive method for the control of low-vibration and high-precision, the process of connecting the permanent magnet synchronous motor and the load may cause the response characteristic of the system to become very unstable, to cause vibration, and to overload the system. In order to solve these problems, various studies such as adaptive control, optimal control, robust control and artificial neural network have been actively conducted. In this paper, an incremental encoder of the permanent magnet synchronous motor is used to detect the position of the rotor. And the position of the detected rotor is used for low vibration and high precision position control. As the controller, we propose augmented state feedback control with a speed observer and first order deadbeat disturbance observer. The augmented state feedback controller performs control that the position of the rotor reaches the reference position quickly and precisely. The addition of the speed observer to this augmented state feedback controller compensates for the drop in speed response characteristics by using the previously calculated speed value for the control. The first order deadbeat disturbance observer performs control to reduce the vibration of the motor by compensating for the vibrating component or disturbance that the mechanism has. Since the deadbeat disturbance observer has a characteristic of being vulnerable to noise, it is supplemented by moving average filter method to reduce the influence of the noise. Thus, the new controller with the first order deadbeat disturbance observer can perform more robustness and precise the position control for the influence of large inertial load and natural frequency. The simulation stability and efficiency has been obtained through C language and Matlab Simulink. In addition, the experiment of actual 2.5[kW] permanent magnet synchronous motor was verified.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.4
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• pp.231-243
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• 2009

Many DSP systems are streaming applications in which streams of data constantly flow through a set of filters. Dataflow programming paradigm is one of effective methods for representing these streaming applications. Dataflow programming model explicitly exposes parallelisms within an application, which helps compiling of the application onto a multicore platform. We propose SPEX(Signal Processing Extension), a language extension to a standard imperative language based on the parameterized dataflow model. Parameterized dataflow model is a kind of dataflow model that can express a modest fashion of dynamism contrary to the synchronous dataflow that can represent only static dataflow. SPEX facilitates characterizing an application written in conventional imperative languages such C/C++ as a streaming application. SPEX is comprised of a few keywords augmented to the conventional C++ syntax for representing dataflow paradigm. SPEX also restricts the syntax and semantics of C++ in order to fit the program within a certain streaming programming category. In this paper, we focus on the capability of SPEX in representing streaming computations within filters and streaming communications among filters.

• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2430-2441
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• 2000

A visual concurrent programming environment, called ESTGVP is designed and implemented, which is easy to understand, highly portable, and can represent parallel behaviors. For our purpose, a conventional state transition graph is extended so as to enable both of synchronous and asynchronous parallel operations. We call it extended state transition graph (ESTG). ESTGVP uses the ESTG and texts for programming, and makes it easy programming sequential and parallel behaviors. Also, it is easy to understand the control structure of a program because ESTGVP is a visual programming environment based on the graph. ESTGVP is written in Tel language and thus it is highly portable on various operating systems. It consists of three major components; edition, transformation and execution. If necessary, ESTG can be transformed into C or Tel language, and its execution is based on Tel.

• Proceedings of the KSPS conference
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• 2006.05a
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• pp.77-81
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• 2006

This paper presents a technique of imposing the prosodic features of a native speaker's utterance onto the same sentence uttered by a non-native speaker. Three acoustic aspects of the prosodic features were considered: the fundamental frequency (F0) contour, segmental durations, and the intensity contour. The fundamental frequency contour and the segmental durations of the native speaker's utterance were imposed on the non-native speaker's utterance by using the PSOLA (pitch-synchronous overlap and add) algorithm [1] implemented in Praat[2]. The intensity contour transfer was also done in Praat. The technique of transferring one or more of these prosodic features was elaborated and its implications in the area of language education were discussed.

• The Journal of the Acoustical Society of Korea
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• v.15 no.3E
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• pp.60-65
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• 1996

This paper describes on the Korean continuous speech recognition system for flight reservation. It adopts a frame-synchronous One-Pass DP search algorithm driven by syntactic constraints of context free grammar(CFG). For recognition, 48 phoneme-like units(PLU) were defined and used as basic units for acoustic modeling of Korean. This modeling was conducted using a HMM technique, where each model has 4-states 3-continuous output probability distributions and 3-discrete-duration distributions. Language modeling by CFG was also applied to the task domain of flight reservation, which consisted of 346 words and 422 rewriting rules. In the tests, the sentence recognition rate of 62.6% was obtained after speaker adaptation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.4
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• pp.523-528
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• 2015

A new algorithm for a coordinative control method is proposed with respect to voltage control and system stabilization of local substations. This is accomplished using control cooperation between a static synchronous compensator (STATCOM) and the existing voltage compensation equipment in the steady state and emergency state of a power system. A real-time system analysis was developed by combining a system analysis program with InTouch, which has primarily been used in factory automation for verification. PSS/E was used for the load flow calculation software, Python for language, Intouch as an HMI program, and MS SQL for the database. To test this system, the system in the vicinity of the Migeum and the Migeum substations was modeled and simulated.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.3
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• pp.76-81
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• 2011

Intrusion prevention systems (IPS) are important solution about solved problems for inside system security or outsider attacks. When introduce this system, first consideration item is secured rather than multiple function. Colored Petri Nets (CPNs) used that in order to secured verification for user authentication function of intrusion prevention system security model. CPNs is a graphical modeling language suitable for modeling distributed, concurrent, deterministic or non-deterministic systems with synchronous. Like these CPNs was expressed every possible state and occurrence graph. Secured of IPS security model was verified because expression every state using CPN tool and as a result of analyzing the occurrence graph was without a loop or interruption.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.361-372
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• 2004

Collaborative and distributed engineering web services are emerging as a viable alternative to the traditional design and engineering process automation. Existing approaches have limitations in supporting long-running engineering transactions, automatic engineering process orchestration and choreography, synchronous and asynchronous conversation, and geometric abstraction for transmission and sharing. In this paper, we present a process-centric engineering web service methodology to overcome these limitations by utilizing BPEL-based (Business Process Execution Language) process templates and coordination broker-based conversation support. This paper discusses the synchronization of engineering web services which can be either peer-centric or process-centric to support long-running engineering transactions and conversation. The process orchestration and choreography broker works as a service dispatching and aggregation mediator for executing process templates, which enables the individual activity or the engineering process to dynamically select and invoke one of the alternative web services through the run-time process brokering. Further, the paper presents how to support collaboration over the running process using conversation policy.