• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2003년도 가을 학술발표회 논문집
• /
• pp.89-96
• /
• 2003

This research presents a methodology for processing design provisions by representing the provisions and also by checking the conformance of design entities with the provisions via STEP information technology, which is considered as a canonical component for implementing CALS. The provisions of standards are represented in the .form of EXPRESS schema including various entities, algorithms, global rules, and local rules, while the schema are managed on EXPRESS engine called EXPRESSO.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
• /
• pp.488-491
• /
• 2005

본 논문에서는 인공지능을 이용해서 엔진오일을 자동으로 교환시스템을 제안 하고자 한다. 모범운전자도, 엔진오일을 교환하는 시기를 정확하게 예측하기란 매우 어렵다. 왜냐하면 엔진오일 색깔이 검은색이거나 주행거리가 3000 km 이상이 되었을 때에 엔진오일을 교환해야만 하는 것이 아니기 때문이다. 최적의 엔진오일 교환시기를 예측하기 위해서는 엔진오일 색깔, 엔진오일 점도와 도로조건, 급제동 및 급발진 조건을 고려해야하기 때문이다. 그러므로 본 논문에서는 이러한 문제점을 해결하기 위해서 퍼지규칙 및 신경망을 이용해서 엔진오일교환시기를 예측하는 전문가시스템을 개발하였다.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 1995년도 추계학술대회 95 KFIS Workshop Realization of Human Friendly System Based on Soft Computiong Techniques
• /
• pp.124-140
• /
• 1995

The merit of fuzzy rule based systems stems from their capability of encoding qualitative knowledge of experts into quantitative rules. Recent advancement in automatic tuning or self-organization of fuzzy rules from experimental data further enhances their power, allowing the integration of the top-down encoding of knowledge with the bottom-up learning of rules. In this paper, methods of self-organizing fuzzy rules and of performing defuzzification and inference is presented based on a multi-resolution radial basis function network. The network learns an arbitrary input-output mapping from sample distribution as the union of hyper-ellipsoidal clusters of various locations, sizes and shapes. The hyper-ellipsoidal clusters, representing fuzzy rules, are self-organized based of global competition in such a way as to ensute uniform mapping errors. The cooperative interpolation among the multiple clusters associated with a mapping allows the network to perform a bidirectional many-to-many mapping, representing a particular from of defuzzification. Finally, an inference engine is constructed for the network to search for an optimal chain of rules or situation transitions under the constraint of transition feasibilities imposed by the learned mapping. Applications of the proposed network to skill acquisition are shown.

• Journal of Electrical Engineering and Technology
• /
• 제12권3호
• /
• pp.1219-1226
• /
• 2017

This paper presents the hybrid stepping machine for linear oscillating generators. The focus of the work is the suggestion of the improved model through the comparison of proposed models ; new flux concentrating PMs mover of the hybrid stepping generator is proposed based on the symmetrical and non-symmetrical stator cores of the surface mounted PMs mover, and non-slanted PMs and slanted PMs of the flux concentrating PMs mover. It is achieved using equivalent magnetic circuit considering leakage elements. Finally, this study suggests new hybrid stepping structure of linear oscillating generator.

• 한국자동차공학회논문집
• /
• 제4권1호
• /
• pp.36-54
• /
• 1996

This paper presents a design procedure of engine power system for vehicle. The implementation and operation environment of engine plant is somewhat diversed through the various kind of vehicles. Regarding this point, we adopt a multi-purposed design objective function which can be easily modified to reflect diverse mount design rules which have been recommended and used generally by relating fields. To search the mount parameters which provide the optimal performance, a direct search method based on an orthogonal array is developed and applied. Through several simulated results, the effectiveness of the developed disign tool is investigated and discussed.

• 대한산업공학회지
• /
• 제23권1호
• /
• pp.197-213
• /
• 1997

It is not easy to find a good production schedule which can be used in practice. Therefore, production scheduling simulation with a simple dispatching rule or a set of dispatching rules is used. However, a simple dispatching rule may not create a robust schedule, for the same rule is blindly applied to all internal production processes. The presumption is that there might be a specific combination of appropriate rules that can improve the efficiency of a total production system for a certain type of orders. In order to acquire a better set of dispatching rules, simulation is used to examine the performance of various combinations of dispatching rule sets. There are innumerable combination of rule sets. Hence it takes too much computer simulation time to find a robust set of dispatching rule for a specific production system. Therefore, we propose a concept of the knowledge based simulation to circumvent the problem. The knowledge based simulation consists of knowledge bases, an inference engine and a simulator. The knowledge base is made of rule sets that is extracted from both simulation and human intuition obtained by the simulation studies. For a certain type of orders, the proposed system provides several sets of dispatching rules that are expected to generate better results. Then the scheduler tries to find the best by simulating all proposed set of rules with the simulator. The knowledge-based simulator armed with the acquired knowledge has produced improved solutions in terms of time and scheduling performance.

• 전기전자학회논문지
• /
• 제17권3호
• /
• pp.332-338
• /
• 2013

BPEL은 작업의 순서를 기술하는 워크플로우의 표준으로서, 웹 서비스를 기반으로 하는 분산 컴퓨팅 환경의 많은 응용 분야에 적용되고 있다. BPEL의 요구사항이 복잡해지면서 규칙기반의 엔진이 요구되고 있다. 본 논문은 BPEL 문법을 그대로 이용하면서 규칙을 추가하기 위해 규칙을 기술할 수 있는 R4BPEL 문서를 제안하고 규칙 웹 서비스를 이용하여 BPEL에 규칙을 사용할 수 있도록 제안한다. BPEL 엔진에 규칙 기능을 추가하기 위해서는 BPEL 엔진을 새롭게 개발하거나 수정해야 하는데, 이 방법은 많은 비용이 많이 필요하다. 제안하는 방법은 기존의 범용 BPEL 시스템에 규칙 웹 서비스와 R4BPEL 문서 분석기를 추가하여 손쉽게 규칙 기반의 BPEL 환경을 구성할 수 있다. 본 논문에서는 제안하는 시스템에서의 BPEL 문서와 기존 방식의 BPEL 문서를 비교하여 제안하는 시스템의 규칙 기반 BPEL 문서가 단순함을 보인다.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 추계 학술대회 학술발표 논문집
• /
• pp.49-52
• /
• 2003

In this research, we propose a mechanism to develop an inference engine and expert systems based on relational database and SQL (structured query language). Generally, former researchers had tried to develop an expert systems based on text-oriented knowledge base and backward/forward (chaining) inference engine. In these researches, however, the speed of inference was remained as a tackling point in the development of agile expert systems. Especially, the forward inference needs more times than backward inference. In addition, the size of knowledge base, complicate knowledge expression method, expansibility of knowledge base, and hierarchies among rules are the critical limitations to develop an expert systems. To overcome the limitations in speed of inference and expansibility of knowledge base, we proposed a relational database-oriented knowledge base and forward inference engine. Therefore, our proposed mechanism could manipulate the huge size of knowledge base efficiently, and inference with the large scaled knowledge base in a short time. To this purpose, we designed and developed an SQL-based forward inference engine using relational database. In the implementation process, we also developed a prototype expert system and presented a real-world validation data set collected from medical diagnosis field.

• Journal of Advanced Marine Engineering and Technology
• /
• 제9권2호
• /
• pp.159-169
• /
• 1985

The calculation of torsional vibration for marine diesel engine propulsion shafting is normally carried out by equalizing exciting energy to damping energy, or using the dynamic magnifier. But, with these methods, the vibration amplitudes are calculated only for resonance points and vibration amplitudes of other running speeds of engine are determined by the estimation. Recently, many energy-saving ships have been built and on these ships, two-stroke, supercharged, super-long stroke diesel engines which have a small number of cylinders are usually installed. In these cases, the first order critical-torsional vibrations of these engine shaftings appear ordinarily near the MCR speed and the stress amplitudes of their vibration skirts exceed the limit stress defined by the rules of classification society. To predict the above condition in the design stage, the synthesized vibration amplitudes of all orders which are summed up according to their phase angles must be calculated from the drawings of propulsion shaft systems. In this study, a theoretical method to fulfill the above calculation is derived and a computer program is developed according to the derived method. And a shafting system of two-stroke, super-long stroke diesel engine which was installed in a bulk carrier is analyzed with this method. The measured values of this engine shafting are compared with those of calculated results and they show a fairly good agreement.

• Journal of Mechanical Science and Technology
• /
• 제14권6호
• /
• pp.655-665
• /
• 2000

We propose an efficient algorithm for the purpose of satisfying a wide range of design constraints represented with equality and inequality equations as well as production rules. The algorithm employs simulated-annealing and a production rule inference engine and works on design constraints represented with networks. The algorithm fulfills equality constraints through constraint satisfaction processes like variable elimination while taking into account inequality constraints and inferring production rules. It can also reduce the load of the optimization procedure if necessary. We demonstrate the implementation of the algorithm with the result on machine tool design.