A quantitative analysis of indicators of scientific performance

Condensing the work of any academic scientist into a one-dimensional indicator of scientific performance is a difficult problem. Here, we employ Bayesian statistics to analyze several different indicators of scientific performance. Specifically, we determine each indicator’s ability to discriminate between scientific authors. Using scaling arguments, we demonstrate that the best of these indicators require approximately 50 papers to draw conclusions regarding long term scientific performance with usefully small statistical uncertainties. Further, the approach described here permits statistical comparison of scientists working in distinct areas of science.     

Optical and electrical properties of zinc oxide films prepared by spray pyrolysis

Zinc oxide thin films were prepared on glass substrates from an aqueous solution of zinc acetate by spray pyrolysis. These films were characterized using X-ray diffraction, scanning electron microscopy and optical transmission. The films were highly transparent to the visible radiation and electrically conductive. Films deposited at optimum conditions exhibited a resistivity of 3·15×10⁻³ Ωm along with a transmittance of 98% at 550 nm.     

Organizing drug injectors against AIDS: Preliminary data on behavioral outcomes.

Describes a project based on organizing drug injectors to change their subculture in ways that promote lower risk behaviors. Initial and follow-up interviews were conducted with 368 Ss. Findings indicate a decline in high-risk behaviors such as renting or borrowing used syringes and an increase in risk-reducing behaviors such as using new syringes and condoms. Almost half the Ss entered drug abuse treatment during the follow-up period; 60% taught others to use bleach to decontaminate injecting equipment. Risk reduction was greater among Ss who attended group meetings. Thus, organizing drug injectors is a feasible intervention that should be adopted elsewhere. Drug injectors can take on responsibility in combating AIDS. All evaluations of interventions should measure Ss' efforts to spread the message to others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Solid-solution composition and powder high-speed steel properties

Translated from Poroshkovaya Metallurgiya, No. 4(316), pp. 52–54, April, 1989.     

Unified overhead-aware schedulability analysis for slot-based task-splitting

Hard real- time multiprocessor scheduling has seen, in recent years, the flourishing of semi-partitioned scheduling algorithms. This category of scheduling schemes combines elements of partitioned and global scheduling for the purposes of achieving efficient utilization of the system’s processing resources with strong schedulability guarantees and with low dispatching overheads. The sub-class of slot-based “task-splitting” scheduling algorithms, in particular, offers very good trade-offs between schedulability guarantees (in the form of high utilization bounds) and the number of preemptions/migrations involved. However, so far there did not exist unified scheduling theory for such algorithms; each one was formulated in its own accompanying analysis. This article changes this fragmented landscape by formulating a more unified schedulability theory covering the two state-of-the-art slot-based semi-partitioned algorithms, S-EKG and NPS-F (both fixed job-priority based). This new theory is based on exact schedulability tests, thus also overcoming many sources of pessimism in existing analysis. In turn, since schedulability testing guides the task assignment under the schemes in consideration, we also formulate an improved task assignment procedure. As the other main contribution of this article, and as a response to the fact that many unrealistic assumptions, present in the original theory, tend to undermine the theoretical potential of such scheduling schemes, we identified and modelled into the new analysis all overheads incurred by the algorithms in consideration. The outcome is a new overhead-aware schedulability analysis that permits increased efficiency and reliability. The merits of this new theory are evaluated by an extensive set of experiments.     

Sorption of polar and nonpolar aromatic organic contaminants by plant cuticular materials: role of polarity and accessibility

In both forest and agricultural soils, plant derived cuticular materials can constitute a significant part of soil organic matter. In this study, the sorption of nonpolar (naphthalene and phenanthrene) and polar (phenol and 1-naphthol) aromatic organic pollutants to aliphatic-rich cuticularfractions of green pepper (Capsicum annuum) (i.e., bulk (PC1), dewaxed (PC2), nonsaponifiable (PC3), nonsaponifiable-nonhydrolyzable (PC4), and dewaxed-hydrolyzed residue (PC5)) were examined to better understand the influence of polarity and accessibility on their sorption behavior. The polarity and structures of cuticular fractions were characterized by elemental analysis, Fourier transform infrared spectroscopy, and solid-state 13C NMR. The sorption isotherms fit well to the Freundlich equation. Sorption of the tested organic compounds to PC4, which had more condensed domains, was nonlinear (Freundlich N(s) values of 0.766-0.966). For naphthalene and phenanthrene, the largest sorption capacity (K(oc)) occurred in PC5, which contained the highest paraffinic carbons (63%) and the lowest polarity: approximately 2 and aproximately 3 times higher than the respective carbon-normalized octanol-water partition coefficient (K(owc)), indicating that PC5 was a powerful sorption medium. For phenol and 1-naphthol, the largest K(oc) values occurred in PC4 with polar aromatic cores: approximattely 17 and approximately 7 times higher than the respective K(owc), suggesting that PC4 was much more accessible and compatible to polar aromatic pollutants than nonpolar aromatic pollutants. There was little or no correlation of K(oc) with either aliphatic or aromatic components of the tested aliphatic-rich sorbents because the polarity and accessibility apparently played a regulating role in the sorption of organic contaminants.     

On transient heat losses from buried district heating pipes

The theory of steady‐state heat loss determination from buried heating pipes has been reviewed as well as previous approaches to treat transient heat losses in the case of constant water temperatures. A new method has been developed to find an undisturbed ground temperature by which the transient heat loss can be calculated by the use of the steady‐state heat loss equations. By numerical simulations, as well as by experiment, the position of this undisturbed ground temperature has been found. The position of this ground temperature is closer to the ground surface in the case of uninsulated pipes—or pipes with the insulation in poor condition—than in the case of insulated pipes. For pre‐insulated pipes the position corresponds approximately to the top of the pipe casing. Copyright © 2000 John Wiley & Sons, Ltd.     

An efficient algorithm for the link allocation problem on ATM-basedpersonal communication networks

The personal communication network (PCN) is an emerging wireless network that promises many new services for the telecommunication industry. The proliferation of demands for extending wireless services to integrated services which supports the transmission of data and multimedia information has resulted in the need for broadband wireless systems that are able to provide service capabilities similar to those of wireline networks. The ATM cell-relay paradigm is one possible approach to provide broadband wireless transmission with PCNs using the ATM switching networks for interconnection of PCN cells. In an ATM-based PCN, the communication path between a pair of mobile terminals might be elongated due to the mobility of the terminals. The link allocation problem is that of allocating backbone links among ATM switches to reduce the effects of terminal mobility on the performance of ATM-based PCNs. Huang and Wang (1997) have shown that this problem is NP-complete. In this paper, we propose a new efficient heuristic algorithm for the link allocation problem. One novel feature of our algorithm is that we are able to derive sufficient conditions under which our algorithm is able to guarantee optimal solutions. Our empirical study shows that the average lengths of communication paths obtained by our algorithm are shorter than those obtained by Huang and Wang's algorithm. In addition, the number of successfully established paths obtained by our algorithm is significantly more than that obtained by the aforementioned