Tight upper bounds for semi-online scheduling on two uniform machines with known optimum

We consider a semi-online version of the problem of scheduling a sequence of jobs of different lengths on two uniform machines with given speeds 1 and s. Jobs are revealed one by one (the assignment of a job has to be done before the next job is revealed), and the objective is to minimize the makespan. In the considered variant the optimal offline makespan is known in advance. The most studied question for this online-type problem is to determine the optimal competitive ratio, that is, the worst-case ratio of the solution given by an algorithm in comparison to the optimal offline solution. In this paper, we make a further step towards completing the answer to this question by determining the optimal competitive ratio for s between \(\frac{5 + \sqrt{241}}{12} \approx 1.7103\) and \(\sqrt{3} \approx 1.7321\), one of the intervals that were still open. Namely, we present and analyze a compound algorithm achieving the previously known lower bounds.

     

Ramsey‐type results for Gallai colorings

A Gallai‐coloring of a complete graph is an edge coloring such that no triangle is colored with three distinct colors. Gallai‐colorings occur in various contexts such as the theory of partially ordered sets (in Gallai's original paper) or information theory. Gallai‐colorings extend 2‐colorings of the edges of complete graphs. They actually turn out to be close to 2‐colorings—without being trivial extensions. Here, we give a method to extend some results on 2‐colorings to Gallai‐colorings, among them known and new, easy and difficult results. The method works for Gallai‐extendible families that include, for example, double stars and graphs of diameter at most d for 2?d, or complete bipartite graphs. It follows that every Gallai‐colored K_n contains a monochromatic double star with at least 3n+ 1/4 vertices, a monochromatic complete bipartite graph on at least n/2 vertices, monochromatic subgraphs of diameter two with at least 3n/4 vertices, etc. The generalizations are not automatic though, for instance, a Gallai‐colored complete graph does not necessarily contain a monochromatic star on n/2 vertices. It turns out that the extension is possible for graph classes closed under a simple operation called equalization. We also investigate Ramsey numbers of graphs in Gallai‐colorings with a given number of colors. For any graph H let RG(r, H) be the minimum m such that in every Gallai‐coloring of K_m with r colors, there is a monochromatic copy of H. We show that for fixed H, RG (r, H) is exponential in r if H is not bipartite; linear in r if H is bipartite but not a star; constant (does not depend on r) if H is a star (and we determine its value). © 2009 Wiley Periodicals, Inc. J Graph Theory 64: 233–243, 2010     

Thermal and spectroscopic studies on a double-salt-type pyridine–silver perchlorate complex having κ1-O coordinated perchlorate ions

Journal of Thermal Analysis and Calorimetry - A simple synthetic method was developed to prepare 4[Agpy2ClO4]·[Agpy4]ClO4 in a low-temperature decomposition process of [Agpy4]ClO4. A detailed...     

Über die Herstellung einiger am Stickstoffatom substituierter 1,3-Propandiol-dicarbamate

Zusammenfassung Während der Untersuchungen über die Chemie der 1,3-Diole wurden zahlreiche N-Monoalkyl- und N,N-Dialkyl-1,3-propandiol-dicarbamate hergestellt. Die 2,2-Dialkyl-1,3-propandiol-dicarbamate sind unter Anwendung von Phosgen erhalten worden. Bei der Synthese der N-Monoalkyl- bzw. der gemischten N,N-Dialkylderivate stellte man zuerst das entsprechende Monocarbamat (V) her, von dem man sodann das gewünschte Endprodukt (VII) durch Umsetzung nach Methode a) oder b) oder c) erhalten konnte.     

Thermoanalytische untersuchungen auf dem gebiet der komplexchemie

This work deals on the one hand with the application of thermal analysis with regards to its use in the chemistry of complex compounds, and on the other hand this paper gives a summary of the results achieved in the field of chemistry of complex compounds.     

Enhanced electron screening in d(d,p)t for deuterated metals

The electron screening effect in the d(d,p)t reaction has been studied for deuterated metals, insulators, and semiconductors, i.e. 58 samples in total. As compared to measurements performed with a gaseous D₂ target, a large effect has been observed in most metals, while a small (gaseous) effect is found, e.g., for the insulators, semiconductors, and lanthanides. The periodic table provides the ordering of the observed small and large effects in the samples. An explanation of the large effects in metals is possibly provided by the classical plasma screening of Debye applied to the quasi-free metallic electrons. The data also provide information on the solubility of hydrogen in the samples.Received: 25 July 2003, Revised: 15 September 2003, Published online: 23 December 2003PACS: 25.10. + s Nuclear reactions involving few-nucleon systems - 25.45.-z ²H-induced reactions - 95.30.-k Fundamental aspects of astrophysicsFor the LUNA Collaboration; supported in part by BMBF (06BO812 and 05CL1PC1/1), GSI (Bo-Rol), DFG (Ro429/31-1 and 436Ung113), OTKA (T034259, T042733, F043408), and Dynamitron-Tandem-Laboratorium Bochum.     

Monolithically integrated bacteriorhodopsin-GaAs/GaAlAs phototransceiver

A monolithically integrated bacteriorhodopsin-semiconductor phototransceiver is demonstrated for the first time to the authors' knowledge. In this novel biophotonic optical interconnect, the input photoexcitation is detected by bacteriorhodopsin (bR) that has been selectively deposited onto the gate of a GaAs-based field-effect transistor. The photovoltage developed across the bR is converted by the transistor into an amplified photocurrent, which drives an integrated light-emitting diode with a Ga0.37Al0.63As active region. Advantage is taken of the high-input impedance of the field-effect transistor, which matches the high internal resistance of bR. The input and output wavelengths are 594 and 655 nm, respectively. The transient response of the optoelectronic circuit to modulated input light has also been studied.     

Electrochemical microgravimetric study on microcrystalline particles of phenazine attached to gold electrodes

Phenazine solid crystals have been attached to gold electrodes and investigated by cyclic and potential step electrochemical quartz crystal microbalance (ECQM) measurements in the presence of aqueous acidic media. The freshly deposited phenazine layers exhibit a break-in phenomenon. The number of potential cycles required for the layer to be fully electroactive depends on its thickness and also on the nature and concentration of the supporting electrolyte as well as on the scan rate. After the break-in, a considerable amount of solvent molecules remains embedded in the surface layer. The protonated and unprotonated forms of phenazine, whose relative amounts depend on the pH of the contacting solutions, are reduced at different potentials; however, the stable product of the first electron transfer is the respective phenazylium salt. During the second reduction step 5,10-dihydrophenazine and charge-transfer complexes of different compositions are formed. Both the current and microgravimetric responses supplied evidences for the structural rearrangements of the solid phases that accompany the redox reactions. The large separation of the reduction and oxidation peaks relates to the additional energy needed to create the solid/solid interface between the reduced and unreduced or partially reduced forms. The chronoamperometric response shows the characteristics of nucleation and growth kinetics. The phase transformation proceeds with the release of hydration water, and the EQCM response is affected by the strain that develops as a consequence of the phase transformation.Dedicated to Prof. Zbigniew Galus on the occasion of his 70th birthday in recognition of his outstanding contributions to electrochemistry     

Urine steroid profile of judo competitors affected by acute physical exercises

A heterogeneous group of 10 male and 15 female judo players are utilized in this study. The subjects complete a standardized maximal treadmill exercise test. Urine samples are collected at the pre- and postexercise stages. The urine steroids are measured using a gas chromatography-mass spectrometry instrument. In rest and after exercise, significantly higher testosterone and epitestosterone concentrations in males (p < 0.01) are found. The etiocholanolone-dehydroepiandrosterone (DHEA) ratio is significantly lower in males than females (p < 0.05). In both males and females, etiocholanolone concentration significantly decreases with the effect of exercise (p < 0.05). 11-OH etiocholanolone concentration also significantly decreases, but only in females (p < 0.05). Positive correlation is found between the changes of the etiocholanolone and epitestosterone concentration caused by exercise.     

METAPRINT: a metabolic fingerprint. Application to cassette design for high-throughput ADME screening

METAPRINT, a metabolic fingerprint, has been developed by predicting metabolic pathways and corresponding potential metabolites. Calculated drug-likeness parameters (log P and MW) have been incorporated into METAPRINT to allow the encoding of metabolic diversity within a chemical library. The application of METAPRINT in the design of cassette dosing experiments is demonstrated using a library of alpha-1a antagonists synthesized at Glaxo Wellcome. Results obtained by Ward's clustering algorithm suggest that METAPRINTs are able to discriminate between low- and high-clearance compounds. Cassette design was performed by maximizing the intracassette Euclidean distances between compounds in METAPRINT space, using simulated annealing. Calculated distances in METAPRINT space were in accordance with experimental data.