A basis for the design of a multiattribute heuristic for single resource project scheduling

Two important characteristics of a project network are the network's topology and the amount of resources available. Most published project scheduling procedures take one or both of these two characteristics into account. Project scheduling procedures that are robust over variations of network characteristics are desirable. The degree of robustness is generally gauged by one or more measures of performance.

The objective of this paper is to compare a set of priority rules that are useful for a single resource project scheduling problem. The set of networks suggested by Patterson (1973) is used along with the set of performance measures proposed by Khattab and Choobineh 1991. The result of this comparison allows one to design a multiattribute heuristic for a single resource project scheduling problem.     

The 'Conceptual Change In Science' project

Abstract This paper outlines the work of the Conceptual Change in Science project, funded as part of the ESRC InTER programme. The aims of this research project are to clarify and describe the process of change in learners' conceptual understandings of natural phenomena. The domain of reasoning selected for study is that of mechanics. Computer software which may be useful in exploring and developing pupils' reasoning and promoting conceptual change in this domain is being developed and evaluated. The group that is carrying out the research is based at the Universities of Leeds, Glasgow and the Open University.     

A Narrowband Pulse-Echo Technique for In Vivo Ultrasonic Attenuation Estimation

The principles of a narrowband technique for pulse echo attenuation measurements are presented. Experiments are described which compare the attenuation in tissue-mimicking phantoms, measured by known methods, to the attenuation measured by the present technique. The effects of various experimental parameters on the results are investigated. The attenuation in spleens of canine models and in livers of human volunteers is presented.     

Life stress and adjustment: Effects of life events experienced by young adolescents and their parents.

A longitudinal design was used to test the effects of life events experienced by young adolescents and their parents. The criteria were the adolescents' depression, anxiety, and self-esteem. The longitudinal analysis revealed a significant effect for the adolescents' controllable, but not uncontrollable, negative events. However, causal analyses revealed that this effect was the result of the significant relation between initial adjustment and the subsequent occurrence of controllable life stress (e.g., school suspension). The longitudinal analysis also revealed the stress-protective role of positive events, but only with respect to girls' self-esteem. There was no longitudinal support for the role of the parents' negative life events. These findings do not support the etiological importance of an accumulation of relatively discrete negative events experienced by early adolescents and their parents, but they do suggest the need (a) to conceptualize (controllable) life stress as a dependent variable in future research on developmental psychopathology; (b) to examine gender differences in early adolescent life stress; and (c) to develop more sophisticated measures of family life stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changing the hydrogen content of alloy steel in relation to the technology used to cool cast slabs

Results are reported from the production of two trial heats of alloy steel in which the cast slabs were cooled in a thermostatted chamber and in a dense stack. It is shown that cooling slabs in such a chamber makes it possible to reduce the hydrogen content of the steel 30% compared to slabs that are cooled while stacked.     

A contribution to the theory of parametric excitation of thermomechanical oscillations

The conditions for a rather fast increase in parametric thermomechanical oscillations have been revealed by using numerical solutions of some types of Hill's equation. It is shown that the occurrence of a real parametric resonance is essentially determined by the character of thermal modulations. It is hypothesized that the indicated trends are observed in oscillations of any physical nature.Stavropol State Pedagogical Institute, Stavropol. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, No. 3, pp. 294–298, September, 1992.     

Reconfigurable arrays by phase-only control

Due to space or cost reasons, a single array antenna can be required to radiate more than one pattern, each pattern being selected by an electronic control, in which only the phase can be modified. A synthesis method for such a problem that is able to determine both the common amplitude and the various phases in an integrated way is presented. Moreover, the approach is flexible enough to take into account additional constraints and allows an efficient implementation. Some test cases showing the effectiveness of the method are presented     

Contact resistance for small contacts [MOSFET]

An asymptotic analysis for current flow to small contacts in MOSFET source/drain regions is obtained. The formula for end resistance is compared with numerical simulations. It shows good agreement for contacts whose width is smaller than half the diffusion width     

High-frequency performance of submicrometer channel-length siliconMOSFETs

Polycide-gate silicon n-channel MOSFETs were fabricated on the basis of a standard 0.5-μm MOS technology and measured over the 1.5-26.5-GHz frequency range, in order to investigate the effects of channel-length reduction on device behavior at high frequency. Excellent microwave performances were obtained with a maximum operating frequency (f_max) and a unity-current-gain frequency f _t near 20 GHz for 0.5-μm-gate-length NMOS devices. An equivalent circuit for a MOSFET with its parasitic elements was extracted from measured S-parameter data. The influence of gate resistance, gate-to-drain overlap capacitance, substrate conductivity, and the transit-time effect between the source and drain on microwave characteristics was analyzed