International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems

This paper deals with aggregation operators. A new form of idempotency, called asymptotic idempotency, is introduced. A critical discussion of the basic notion of aggregation operator, strictly connected with asymptotic idempotency, is provided. Some general construction methods of symmetric, asymptotically idempotent aggregation operators admitting a neutral element are illustrated.

Linguistic information aggregation has received great attention from researchers, and a variety of operators have been developed for aggregating linguistic information. All the existing linguistic information aggregation operators only consider the situations where all the aggregated linguistic arguments are independent, i.e., they only consider the addition of the importance of individual linguistic arguments, however, in some actual situations, the considered linguistic arguments may be correlative. In this paper, we focus on this issue. Motivated by the idea of the well-known Choquet integrals,¹ we propose two new linguistic information aggregation operators called the linguistic correlated averaging operator and linguistic correlated geometric operator. In the special cases where the aggregated linguistic arguments are independent, the linguistic correlated averaging operator can be reduced to a variety of traditional linguistic averaging aggregation operators; while the linguistic correlated geometric operator can be reduced to a variety of the traditional linguistic geometric aggregation operators. Furthermore, we extend the above results to accommodate uncertain linguistic environments, and illustrate them with a practical problem.

The purpose of this paper is to present a new rough set model for generating negative rules from the incomplete information system. A negative rule indicates that if an object does not satisfy the attribute-value pairs in the condition part, then we can exclude the decision part from such object. The proposed rough set model is constructed on the basis of a difference relation. Such difference relation is a binary relation without any constraints. Moreover, to simplify the negative rules generated from the difference relation-based rough approximations, the concepts of lower, upper approximate and rough reducts are also proposed. Some numerical examples are employed to substantiate the conceptual arguments.

Construction firms that work on a contractual basis are generally more concerned with short-term rather than long-term financial strategies. The main focus in short-term financial strategies is on working capital management (WCM). Cash management is a major factor for achieving good liquidity and profitability. In this study we take into consideration the cash component of working capital management based on the target cash balance. We develop a practical model that should allow Taiwan construction firms to utilize the currently available cash and assets at any point in time in the most rational way. To help understand the issues involved, we first introduce a model developed by Miller and Orr. The relationship between project duration and progress towards completion is most effectively represented in practical construction management by the S-curve. Thus, in this study we plot the fuzzy S-curve regression based on the Takagi-Sugeno (T-S) fuzzy model. The practicality of the model is demonstrated using project cash flow and progress payment records from a sample project. The data are obtained from the Taipei City Government's Department of Rapid Transit Systems. Some tentative conclusions concerning the model are also given.

We prove for outer continuous belief measures defined on compact spaces strong and weak laws of large numbers as Kolmogorov's one for measures. These results contribute to M. Marinacci's (Journal of Economic Theory84 (1999) 145–195) though with different methods.

This study examines the feasibility of applying adaptive fuzzy sliding mode control (AFSMC) strategies to reduce the dynamic responses of bridges constructed using a lead rubber bearing (LRB) isolation hybrid protective system. Recently developed control devices for civil engineering structures, including hybrid systems and semi-active systems, have been found to have inherent nonlinear properties. It is thus necessary to develop non-linear control methods to deal with such properties. Generally, controller fuzziness increases the robustness of the control system to counter uncertain system parameters and input excitation, and the non-linearity of the control rule increases the effectiveness of the controller relative to linear controllers. Adaptive fuzzy sliding mode control (AFSMC) is a combination of sliding mode control (SMC) and fuzzy control. The performance and robustness of these proposed control methods are all verified by numerical simulation. The results demonstrate the viability of the presented methods. The attractive control strategy derived there-from is applied to seismically excited bridges using LRB isolation.

The need of developing appropriate noise prediction models for finding out the accurate status of noise levels (>90 dBA) generated from various opencast mining machineries is overdue. The measured sound pressure levels (SPL) of equipments are not accurate due to instrumental error, attenuation due to geometrical aberration, atmospheric attenuation etc. Some of the popular noise prediction models e.g. VDI and ENM have been applied in mining and allied industries. Among these models, VDI2714 is simple and less complex model. In this paper, a neuro-fuzzy model is proposed to predict the machinery noise in an opencast coal mine. The proposed model is trained with VDI2714 and the model output is seen very closely to matching with VDI2714 output. The model proposed has a mean square error of 2.73%. This model takes CPU time of nearly 0.0625 sec where as it takes 0.5 sec for VDI2714 i.e. approximately twelve times faster.

In this study, using fuzzy-rough set and intuitionistic fuzzy set approaches, we propose a cognitive structural model for the concept of life for which a certain definition can not be made because of scientific uncertainty as well as moral, legal, and theological aspects. Total 191 first-year students from seven different high schools in a large western city in Turkey participated in the study. An open-ended conceptual understanding (CULC) test, developed by the researcher, was used for data collection. Semi-structured interviews were carried out with 14 students and their biology teachers to clarify ambiguous points in students' responses to the CULC test. The results of analyses indicated that students constructed the concept of life by associating it predominantly with 'human'. Motion appeared as the most frequently associated term with the concept of life. The results suggest that the life concept has been constructed using animistic-anthropocentric cognitive schemes. In the next step, we evaluated the data obtained from the CULC test using the fuzzy-rough set and intuitionistic fuzzy set theories. Consequently, we propose an 'animistic-anthropocentric structural model' about cognitive construction of the concept of life.

This section is maintained by Vladik Kreinovich. Please send your abstracts (or copies of papers that you want to see reviewed here) to vladik@utep.edu, or by regular mail to: Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA.