First-order logic (FOL) is undecidable — that is, no algorithm exists that can decide whether a formula of FOL is valid or not. However, there are various fragments of FOL that are known to be decidable. FO, the two-variable fragment of FOL, is one of such languages [1,2]. FO is a first-order language where formulas have maximally two variables, no function symbols, but possibly do have equalit...

Several models have been proposed for scheduling the preventive maintenance (PM) of complex repairable systems in industry. These are often application-speci"c and some make unrealistic assumptions about stationarity of the process and quality of repairs. We investigate two principal types of general model, which have wider applicability. The "rst considers "xed PM intervals and is based on the...

The both Atlantic side relations from the ancient time had been faced with too much challenge but the continuing of this relation is due to the common political and economical interests. The upper Atlantic and the two organizations (NATO, EU) still exist to gain the essential goals and the political and security connection which are boosting with the economical integration at the same time. But...

the both atlantic side relations from the ancient time had been faced with too much challenge but the continuing of this relation is due to the common political and economical interests. the upper atlantic and the two organizations (nato, eu) still exist to gain the essential goals and the political and security connection which are boosting with the economical integration at the same time. but...

in order to reduce herbicide utilization, a 3-year field experiment was carried out with integration of mechanical and chemical weed control methods; in mechanical method, three types of blades (curred- bed knife, square- turn knife and sweep) were used. chemical control was done with chloridazon (wp 80%) and desmedipham (ec 15.7%) in two spraying sheme: once band sparying with 2 l h-1 & twice ...

The reuse and integration of Open Source Software (OSS) components provided by OSS communities is becoming an economical and strategic need for today’s organizations. The integration of OSS components provides many benefits, but also risks and challenges. One of the most important risks is the lack of effective and timely OSS community support for dealing with possible integration problems. For...

Information processing in the cerebral cortex requires the activation of diverse neurons across layers and columns, which are established through the coordinated production of distinct neuronal subtypes and their placement along the three-dimensional axis. Over recent years, our knowledge of the regulatory mechanisms of the specification and integration of neuronal subtypes in the cerebral cort...

The integration of distributed sources into existing networks brings up several technical, economical and regulatory questions. In terms of physical integration, protection is one of the major issues. Therefore new protection schemes for both distributed generators (DG) and utility distribution networks have been developed in the recent years, but there are still open questions. This document i...

Enterprise computing often takes the form of automation islands, and lots of business operations must be built on these islands. Then reusing existing components and creating integrated, flexible, reliable applications which can be combined for maximum productivity have become the imperative for an enterprise to survive and thrive in the new competitive and dynamic business environment. In the ...

This paper examines the storage application and its optimal placement for the social cost and transmission congestion relief of wind integration. Probability density functions (PDFs) are used to characterize the uncertainties of wind speed and load. A probabilistic optimal power flow (POPF) is developed using two-point estimation which incorporates the storage system either as a variable load o...