Journal of Intelligent & Fuzzy Systems - Volume 14, issue 1

Authors: Al-Jamal, Rami | Manoli, Samir | Brito, Alejandro E. | Kosheleva, Olga

Article Type: Research Article

Abstract: In communications, often, statistical characteristics of the noise vary so much that, in essence, we can only have interval estimates for this noise. We show that under this interval uncertainty, the optimal multiplexing technique consists of using Walsh functions. This result provides a new theoretical explanation for the success of Walsh-based multiplexing techniques which are actively used in cellular phones and in other types of wireless communication.

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 1-6, 2003

Authors: Yager, Ronald R. | Kreinovich, Vladik

Article Type: Research Article

Abstract: In this paper, we develop a relationship between two approaches to combining evidence: the Ordered Abelian Group (OAG) approach and the uninorm approach. We show that while there exist uninorms that are not extended OAG's it turns out that for operations which are continuous (in some reasonable sense), these two approaches coincide.

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 7-12, 2003

Authors: Oudshoff, A.M. | Bosloper, I.E. | Klos, T.B. | Spaanenburg, L.

Article Type: Research Article

Abstract: Automatic knowledge discovery from texts (KDT) is proving to be a promising method for businesses today to deal with the overload of textual information. In this paper, we first explore the possibilities for KDT to enhance communication in virtual communities, and then we present a practical case study with real-life Internet data. The problem in the case study is to manage the very successful virtual communities known as 'clubs' of the largest Dutch Internet Service Provider. …It is possible for anyone to start a club about any subject, resulting in over 10,000 active clubs today. At the beginning, the founder assigns the club to a predefined category. This often results in illogical or inconsistent placements, which means that interesting clubs may be hard to locate for potential new members. The ISP therefore is looking for an automated way to categorize clubs in a logical and consistent manner. The method used is the so-called bag-of-words approach, previously applied mostly to scientific texts and structured documents. Each club is described by a vector of word occurrences of all communications within that club. Latent Semantic Indexing (LSI) is applied to reduce the dimensionality problem prior to clustering. Clustering is done by the Within Groups Clustering method using a cosine distance measure appropriate for texts. The results show that KDT and the LSI method can successfully be applied for clustering the very volatile and unstructured textual communication on the Internet. Show more

Keywords: knowledge discovery in text, clustering, virtual community, latent semantic indexing, web portal

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 13-24, 2003

Authors: Baǧiş, Aytekin

Article Type: Research Article

Abstract: In this paper a new and efficient control method based on the integration of classical proportional-derivative controller and a fuzzy logic controller proposed for real-time operation of spillway gates of a reservoir during any flood of any magnitude up to the probable maximum flood. In order to demonstrate the high performance of the proposed method, we simulate the control system using different probable overflow hydrographs. The results of the proposed control method are compared with the …results of the conventional control methods. The results obtained from the simulations indicate that the proposed method exhibits high performance over the conventional reservoir flood operation with much more desirable results. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 25-36, 2003

Authors: Dounis, A.I. | King, R.E.

Article Type: Research Article

Abstract: This paper presents a design procedure for a class of optimized semi-active controllers for structures subjected to seismic activity. The structure is controlled through a single force applied to a controllable electromagnetic damper placed on the first storey of the structure. The restraining control force is computed in real-time using a fuzzy sliding mode control algorithm. The parameters of the controller are optimized using a global stochastic search based on the Metropolis simulated annealing algorithm. …The resultant disturbance mitigation of the proposed controller has been verified through extensive simulation of a multi-storey structure using realistic earthquake data. In this paper a new form of semi-active controller is proposed. The proposed fuzzy sliding mode controller possesses three parameters whose optimum values are computed using simulated annealing. Through simulation of a six storey structure subjected to known earthquake tremors it is shown that the performance of the proposed controller is superior to other semi-active control scheme that have been proposed thus far. Show more

Keywords: fuzzy sliding mode control, semi-active devices, simulated annealing, earthquakes, structure control, magnetorheological and electrorheological dampers

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 37-47, 2003

Authors: Al-Assaf, Yousef

Article Type: Research Article

Abstract: This paper considers the use of MultiResolution Wavelets Analysis (MRWA) to classify speech for multifunctional control applications. While the classification problem is the focus of this paper, the ultimate goal is to improve speech analysis and their application performances. The proposed method performance was compared to that of temporal-time domain features with ANN classification. Results have shown that MRWA resulted in higher recognition rate and consistent output demonstrating higher reliability.

Keywords: speech analysis, classification, neural networks, wavelets analysis

Citation: Journal of Intelligent & Fuzzy Systems, vol. 14, no. 1, pp. 49-58, 2003