• 산업기술연구
• /
• 제20권B호
• /
• pp.155-162
• /
• 2000

Although Fuzzy Logic Controller(FLC) adopted three terms as input gives better performance, FLC is in general composed of two-term control because of the difficulty in the construction of fuzzy rule base. In this paper, a three-term FLC which is similar to PID control but acts as a nonlinear controller is proposed. To reduce the complexity of the rule base design and to increase efficiency. a simplified fuzzy PID control is induced from a hybrid velocity/position type PID algorithm by sharing a common rule base for both fuzzy PI and fuzzy PD parts. It is simple in structure, easy in implementation, and fast in calculation. The phase plane technique is applied to obtain the rule base for fuzzy two-term control and the resultant rule base is Macvicar-Whelan type. And the membership function is a Gaussian function. The frequency response information is used in tuning of the membership functions. Also a tuning strategy for the scaling factors is proposed based on the relationship between PID gain and the scaling factors. Simulation results show better performance and the effectiveness of the proposed method.

• 한국실내디자인학회논문집
• /
• 제17권2호
• /
• pp.30-38
• /
• 2008

It has been stated that the outer skin of an architecture should be related to and express the interior programs. It was rather moral issue than practicality. In contemporary urban cities, this nicely-linked relationship between exterior and interior has become much more complex and, in many cases, is no more valid. It tends that contemporary architectural skin is somehow separately developed and has its own logic to be independent from what is inside. This research focuses on these sort of logical design process to make unique image of skin in which conceptual thinking, spatialization and materialization are mixed together. More specifically this study articulates' expandable patternization process' based on the notion that it has a crucial role to systematically construct an image of skin. Expandable patternization has a couple of stages to complete an architectural skin. The first element is a single unit and the second is organization or arrangement of units based on a logical process. Lastly, the third is spatialization after relating the skin to the interior programs as well as environmental surroundings. It is found that, although, in most related projects, the architect or designer has followed his or her own preference or design tendencies, many skin projects has based the given unique characteristics from the beginning. This study concludes that skin design is not just an image making, but has an important role to amalgamate various aspects of an architectural projects: programs, concept of architect, environment, structure as well as image.

• Computers and Concrete
• /
• 제6권4호
• /
• pp.281-303
• /
• 2009

The lack of safety of bridge deck structures causes frequent repair and strengthening of such structures. The repair induces great loss of economy, not only due to direct cost by repair, but also due to stopping the public use of such structures during repair. The major reason for this frequent repair is mainly due to the lack of realistic and accurate assessment system for the bridge decks. The purpose of the present research was to develop a realistic expert system, called Bridge Slab-Expert which can evaluate reasonably the condition as well as the service life of concrete bridge decks, based on the deterioration models that are derived from both the structural and environmental effects. The diagnosis assessment of deck slabs due to structural and environmental effects are developed based on the cracking in concrete, surface distress and structural distress. Fuzzy logic is utilized to handle uncertainties and imprecision involved. Finally, Bridge Slab-Expert is developed for prediction of safety and remaining service life based on the chloride ions penetration and fick's second law. Proposed expert system is based on user-friendly GUI environment. The developed expert system will allow the correct diagnosis of concrete decks, realistic prediction of service life, the determination of confidence level, the description of condition and the proposed action for repair.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 D
• /
• pp.2239-2241
• /
• 2003

A new RF control system of Pohang Accelerator Laboratory (PAL) storage ring is a subsystem upgraded PAL control system, which is based upon Experimental Physics and Industrial Control System (EPICS). There are 5 control components, Low Level RF System (LRS), Klystron System, Circulator System, Cavity System, Local Cooling Water System (LCW) at the storage ring of PAL. The new RF control system for the storage ring has been under development for one years, first versions of individual VME (Versa Module Europa) Input/output modules under construction and system integration begun. In this system, VMEbus-based hardware is widely used for front-end controllers (FDS), Input/output controller (IOC). A number of Programmable Logic Controller (PLC) and SUN workstations are also used for Operator Interfaces (OPI) in the control system. This paper describes the development VME I/O module to the new control system and how the design of this new system.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제8권3호
• /
• pp.175-184
• /
• 2008

To construct user profiles automatically, an extraction method for representative keywords from a set of documents is needed. In our previous works, we suggested such a method and showed its usefulness. Here, we apply it to the classification problem and observe how much it contributes to performance improvement. The method can be used as a linear document classifier with few modifications. So, we first evaluate its performance for that case. The method is also applicable to some non-linear classification methods such as GIS (Generalized Instance Set). In GIS algorithm, generalized instances are built from training documents by a generalization function and then the K-NN algorithm is applied to them, where the method can be used as a generalization function. For comparative works, two famous linear classification methods, Rocchio and Widrow-Hoff algorithms, are also used. Experimental results show that our method is better than the others for the case that only positive documents are considered, but not when negative documents are considered together.

• Advances in concrete construction
• /
• 제11권1호
• /
• pp.1-9
• /
• 2021

This article discusses the issue of optimizing controller design issues, in which the artificial intelligence (AI) evolutionary bat (EB) optimization algorithm is combined with the fuzzy controller in the practical application of the building. The controller of the system design includes different sub-parts such as system initial condition parameters, EB optimal algorithm, fuzzy controller, stability analysis and sensor actuator. The advantage of the design is that for continuous systems with polytypic uncertainties, the integrated H2/H∞ robust output strategy with modified criterion is derived by asymptotically adjusting design parameters. Numerical verification of the time domain and the frequency domain shows that the novel system design provides precise prediction and control of the structural displacement response, which is necessary for the active control structure in the fuzzy model. Due to genetic algorithm (GA), we use a hierarchical conditions of the Hurwitz matrix test technique and the limits of average performance, Hierarchical Fitness Function Structure (HFFS). The dynamic fuzzy controller proposed in this paper is used to find the optimal control force required for active nonlinear control of building structures. This method has achieved successful results in closed system design from the example.

• 드라이브 ㆍ 컨트롤
• /
• 제19권2호
• /
• pp.17-26
• /
• 2022

Recently, automatic transmissions caused a good improvement in the shift quality of a forklift. An advanced shift control algorithm, which was based on TCU firmware, was applied with embedded control technology and microcontrollers. In the clutch-to-clutch shifting, one friction element is released and the other friction element is activated. During this process, if the release and application timings are not synchronized, an overrun or tie-up occurs and ultimately leads to a shift shock. The TCU, which measures only the speed of the forklift, inevitably applies the open-loop shift control. In this situation, the speed ratio does not change during the clutch fill. The torque phase occurs until the clutch is disengaged. In this study, an offline shift logic of the learning control was proposed. It induced a synchronous shift when the learning control progressed. During this process, the reference current trajectory of the release clutch was corrected and applied to the next upshift. We considered the results of the overrun/tie-up characteristics of the upshift performed immediately before. The vehicle test proved that the deviation in shift quality, which was caused by the difference in the mechanical characteristics of the clutch, could be improved by the learning control.

• 환경영향평가
• /
• 제16권6호
• /
• pp.467-483
• /
• 2007

Environmental Impact Assessment (EIA) is a kind of planning technique to seek ways to minimize environmental impact, a scheme to encourage sustainable development. With the launch of the Ministry of Environment in 1980, the EIA was introduced in Korea. Its full operation was initially driven by regulations on documenting EIA reports in 1981, which was piloted as a decision-making scheme where final decision were made at the development department after considering opinions suggested by the Ministry of Environment. At that time, dominance of the economic logic overwhelmed environ-friendly opinions, but thanks to the fourth revision of the Environmental Conservation Law in 1986, private projects came to be included on the EIA list. This was a turning point for the EIA to become a regulatory system. Local governments are also conducting the EIA regardless of the national-level EIA. In order to prevent and resolve increasingly severe environmental problems in Seoul in advance due to various construction projects, the Seoul Metropolitan Government, for the first time as a local government in Korea, legislated city decrees to introduce the EIA which has been underway from September 1, 2002. In particular, the Seoul government, unlike the Ministry of Environment, has included construction works on the list of evaluation projects, adopting the scoping and screen procedure scheme. In addition, complementing operational setbacks, the city government has revised and implemented decrees and enforcement laws on the Impact Assessment on Environment, Transportation and Disasters by shortening the consultation period, eliminating the submission of reports on construction, and expanding the waiver requirements in consultation over the reports. Therefore, development measures for the EIA scheme of the Seoul Metropolitan Government will be the target of the research. To that end, the up-to-date data of the Ministry of Environment, the Seoul government and local governments was collected, and latest materials from the EU, previous research and the Internet were gathered for analyses. By doing so, the flow of the EIA was reviewed, and the EIA schemes of local governments under the national EIA were analyzed. Furthermore, based on the Seoul government's recent data on the EIA based on the decrees, the background and legislation of the Seoul government's EIA were analyzed along with the developments for the environmental organizations. Setbacks were derived from the implementation period, evaluation procedures, consultation period and details of the EIA, and corresponding development measures were proposed.

• 한국지리정보학회지
• /
• 제4권1호
• /
• pp.34-46
• /
• 2001

GIS를 공간의사지원시스템(SDSS)으로 활용하는데 있어서 기존의 단순중첩에 의한 불린(Boolean) 분석기법은 정보의 과도한 손실과 요소간 가중치를 반영하지 못하는 문제점이 있었다. 이 연구의 목적은 토지정보시스템을 활용하면서 퍼지논리와 AHP기법을 활용하여 적지분석에 관한 사례연구를 하고자 하는 것이다. 포항시 테크노파크의 사례분석 결과에 의하면, 기존의 불린분석에 의한 적지 분석에서는 분석항목간의 가중치 차이가 반영되지 못하였고, 주거용도, 상업연구용도, 공원녹지용도의 적지로 8.0~16.1%의 지역을 분석해 내었다. 퍼지논리와 AHP분석을 병행한 경우에는 분석항목의 중요도에 따른 가중치가 적용되었고, 해당 지역의 적합도를 4등분하였을 때에 32.9~37.4%에 이르는 지역을 가장 적합한 지역으로 분석해 내었으며, 다음 차순의 지역에 관한 정보까지 제공받을 수 있었다. 이를 통해서 퍼지논리와 AHP분석을 활용한 방법이 객관적이면서 융통성있는 분석을 할 수 있는 방법임을 확인할 수 있었다.

• 한국사회복지학
• /
• 제56권1호
• /
• pp.181-201
• /
• 2004

사회복지시설은 역사적으로 다양하고도 심각한 문제를 표출시켜 왔는데, 지역복지를 상위분야로 한 각 대안들이 국내에서 사회복지시설을 지역복지실천의 영역에서 제외시키고 있다. 그러나 사회복지시설의 본연의 역할에 비추어 볼 때, 이러한 대안들은 논리적인 문제를 안고 있다고 할 수 있다. 이러한 문제인식 하에서 본고는 일본에서의 지역복지 중 지역복지의 구성내용, 지역복지에서의 사회복지시설에 대한 규정, 지역복지 범주에서 논의되고 있는 시설사회화론을 이론적으로 제시한다는 연구목적을 제시하였다. 연구결과에 의하면, 지역복지의 중요한 요소로서, 그리고 지역복지를 발전시키는 추진력으로서 사회복지시설이 규정되고 있다는 점과 시설사회화론 또한 지역복지를 발전시키기 위한 주요한 실천이론으로서 논의되고 있으며, 지역개방 측면만이 아니라 이를 포괄한 시설의 근본적인 개혁의 논리로서 제시되고 있다는 점이 밝혀졌다.