• 조명전기설비학회논문지
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• 제20권4호
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• pp.49-55
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• 2006

PLC를 사용한 공정제어에서 일반적으로 LD 언어로 가장 많이 프로그램한다. 그러나 최근에는 SFC 언어에 대한 연구가 활발히 이루어지고 있다. PLC를 사용한 공정제어에서 SFC 언어로 프로그램할 때는 처음부터 마지막까지 하나의 루틴으로 설계하는 것이 일반적이다. 이러한 방법은 설계하기가 무척 힘들고, 흔히 실수하는 경우가 많다. 본 논문에서는 개별 서브시스템을 설계하고, 각 서브시스템을 결합하는 방법을 제안하였고, 실례를 통해 그의 타당성을 확인하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.307-312
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• 2008

Local damage may cause sequential collapse of structure, which is called progressive collapse. Current progressive collapse analysis is based on the mean value of design variables. This deterministic approach has a low reliability as it doesn't consider uncertainty of variables. In this study the sensitivity of design variables for progressive collapse of structure is evaluated by Monte Calro simulation and Tornado diagram. The analysis results show that the behaviour of model structures is highly sensitive to variation of the yield force of beams and the structural damping ratio.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.7-10
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• 2002

The diagnosis of faults of machine tool, which is controlled by CNC and PLC, is generally based on ladder diagram of PLC. Because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching for logical relation to fault reasons is required a lot of fault experiences and times, because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault lastly and correctly. The diagnosed reasons for fault are tele-serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권1호
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• pp.106-106
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• 1999

When we design real-time software target system is analyzed and then we structure sequential executive modules into concurrent tasks. As a result of the analysis, control flow and dataflow diagram based on the RTSA notation is produced. This diagram is structured into concurrenttasks under the condition that performance problem is not serious. The criteria structuring concurrenttasks are introduced as Concurrent Design Approach for Real-Time System(CODARTS) by Gomaa.But structuring concurrent tasks using the criteria of CODARTS is somewhat difficult because thecriteria are dependent on designer's experience. CODARTS is an wide-range and abstractmethodology. As a result, the design can be inconsistent and peoples can understand it differently Inthis paper, we restructure the CODARTS methodology, propose a revised CODARTS structure andrepresent the task structuring steps for this new framework to overcome the understanding andinconsistency problems. The revised CODARTS framework and task structuring steps can be used toautomate the design of real time concurrent software systems. Finally, we show an example of taskstructuring in revised CODARTS framework.

• 한국정밀공학회지
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• 제20권10호
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• pp.89-97
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• 2003

The faults diagnosis of machine tool, which is controlled by CNC(Computer Numerical Control) and PLC(Programmable Logic Controller), is generally based on ladder diagram of PLC because sequential controls for CNC and servo motor are mostly processed in PLC. However, when fault is occurred, a searching of logical relationship for fault reasons is required a lot of diagnosis experiences and times because PLC program has step structure. In this paper, FDS(Fault Diagnosis System) is developed and implemented to machine tool with open architecture controller in order to find the reason of fault fast and correctly. The diagnosed reasons for fault are remote serviced on web through developed RSS(Remote Service System). The operationability and usefulness of developed system are evaluated on specially manufactured machine tool with open architecture CNC. The results of this research can be the model of remote monitoring and fault diagnosis system of machine tool with open architecture CNC.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2002년도 춘계학술발표논문집 (하)
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• pp.1013-1016
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• 2002

제어 시스템에 사용되는 흐름 제어 언어로는 IL(Instruction List), ST(Structured Text), FBD(Function Block Diagram), SFC(Sequential Function Chart), LD (Ladder Diagram)가 있다. 일반적으로 제어 시스템에 탑재하여 사용하는 언어는 상기 언어 중 두 종류 이하의 특정 언어로 제한되어 있다. 이러한 제약을 보완하기 위해, 모든 흐름 제어 언어를 통합 분석할 수 있는 통합 분석기가 필요하다. 본 논문에서는 흐름 제어 언어의 통합 분석 처리가 가능하도록 그래픽 표현의 FBD 를 문자 표현의 EST(Extended Structured Text)로 변형하는 규칙과 문자 표현의 EST 를 IL 로 변형하는 규칙을 제시한다. 언어간의 변형 과정에서 FBD 를 ST 로 표현할 수 없는 부분을 EST 로 정의한다. 또한 본 논문에서 제안된 EST 를 기반으로 통합 분석기의 구조를 제시한다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.65-78
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• 2017

Single Event Transient has a critical impact on highly integrated logic circuits which are currently common in various commercial and consumer electronic devices. Reliability against the soft and intermittent faults will become a key metric to evaluate such complex system on chip designs. Our previous work analyzing soft errors was focused on parallelizing and optimizing error propagation procedures for individual transient faults on logic and sequential cells. In this paper, we present a new propagation technique where a fault binary decision diagram (BDD) continues to merge every new fault generated from the subsequent logic gate traversal. BDD-based transient fault analysis has been known to provide the most accurate results that consider both electrical and logical properties for the given design. However, it suffers from a limitation in storing and handling BDDs that can be increased in size and operations by the exponential order. On the other hand, the proposed method requires only a visit to each logic gate traversal and unnecessary BDDs can be removed or reduced. This results in an approximately 20-200 fold speed increase while the existing parallelized procedure is only 3-4 times faster than the baseline algorithm.

• 조명전기설비학회논문지
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• 제22권4호
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• pp.153-158
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• 2008

PLC를 사용한 제어 시스템을 설계할 때 여러 종류의 표준언어중 LD언어가 가장 많이 사용되지만, SFC를 사용하면 제어의 흐름을 알기 쉽고 유지보수가 용이하며, 프로그램의 기술성이 뛰어나다. 그러나 SFC 언어는 조건처리시 큰 메모리를 요구한다는 단점이 있다. 따라서 SFC로 설계된 시스템은 자기진단기능을 부가하려면 메모리가 상당히 커야 하고, 속도가 늦은 단점이 있다. 이러한 문제점을 해결하기 위해 본 논문에서는 자기진단 기능을 효율적으로 처리하는 방법을 제시하고, 실례를 통해 타당성을 확인하였다.

• Communications for Statistical Applications and Methods
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• 제13권3호
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• pp.755-764
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• 2006

Most graphical methods for categorical data can describe the structure of data and represent a measure of association among categorical variables. Among them the polyhedron plot represents sequential relationships among hierarchical log-linear models for a multidimensional contingency table. This kind of plot could be explored to describe the differences among sequential models. In this paper we suggest graphical methods, containing all the information, that reflect the relationship among all log-linear models in a certain hierarchical structure. We use the ideas of a correlation diagram.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.894-899
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• 1991

GRAFCET is the program language for a sequential control and utilized in the description of sequence of a process. This study is to implement GRAFCET editor and compiler for personnel computer. The GRAFCET editor module is developed to use as menu-driven method based on the graphic screen and the graphic symbol. So, users can use it interactively. The GRAFCET compiler module analyzes the already drawed GRAFCET diagram, then translates it to Z80 assembly code. After generating Z80 machine code from assembly code, we can send the outputed machine code file to Z80 one-board computer through RS232C. We have developed the GRAFCET programming tool to utilize under IBM PC/AT with the VGA monitor, and it may be contribute to low cost automation system.