We argue that the detection of entailment and contradiction relations between texts is a minimal metric for the evaluation of text understanding systems. Intensionality, which is widespread in natural language, raises a number of detection issues that cannot be brushed aside. We describe a contexted clausal representation, derived from approaches in formal semantics, that permits an extended range of intensional entailments and contradictions to be tractably detected.

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Recent trends in broadband access technology show the demand to extend the used frequency bands up to hundreds of MHz. Access cables are not built for such high frequencies, and measurements of access cables in this frequency range show a significant change of the cable characteristics compared to low frequencies.The novel modeling approach presented here is designed to be used for evaluation of transmission technologies for fiber-copper hybrid networks, so called FTTdp (Fiber To The distribution point), which enables service providers to serve customers with data rates in the GBit/s range without the requirement to install fiber to the home.

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Increasing deployment of digital subscriber line (DSL) technology operating in the long wave, medium wave and sometimes short wave frequency ranges, has raised the question of how such systems interact with rival radio frequency sources and equipment. Two of the major standards bodies in the field, ITU and ETSI, imposed by the standardization of such promising technologies like ADSL, SHDSL and VDSL, have recently begun to elaborate performance tests for radio frequency interference (RFI) scenarios for inclusion into their standards documents. Existing outdoor loops of the copper telephone network can have large dimensions, are often unshielded and sometimes not even twisted, thus, they can act like antennas for both RFI egress and ingress. The RFI egress issue requires basic knowledge of the relationship between a given current distribution () on a twisted pair communication cable and the electromagnetic field , generated by that current distribution at a given distance. This problem is reciprocal to the RFI ingress issue, which requires knowledge of the relationship between a disturbing high-frequency electric field in the surroundings of a twisted pair cable, and the terminal voltage of that cable across a load impedance. This contribution provides the theoretical background to the field theoretical problem and supplies simple yet accurate approximation formulae for the prediction of RFI egress and RFI ingress.