Three tokens in Herman’s algorithm

Herman’s algorithm is a synchronous randomized protocol for achieving self-stabilization in a token ring consisting of N processes. The interaction of tokens makes the dynamics of the protocol very difficult to analyze. In this paper we study the distribution of the time to stabilization, assuming that there are three tokens in the initial configuration. We show for arbitrary N and for an arbitrary timeout t that the probability of stabilization within time t is minimized by choosing as the initial three-token configuration the configuration in which the tokens are placed equidistantly on the ring. Our result strengthens a corollary of a theorem of McIver and Morgan (Inf. Process Lett. 94(2): 79–84, 2005), which states that the expected stabilization time is minimized by the equidistant configuration.     

Trends in Reverse-Current Change in Tunnel MIS Diodes with Calcium Fluoride on Si(111) Upon the Formation of an Extra Oxide Layer

Semiconductors - The currents flowing in metal–CaF2–n-Si and metal–SiO2–CaF2–n-Si structures with the same (about 1.5 nm) fluoride thickness are compared in the...     

Algorithmic probabilistic game semantics

We present a detailed account of a translation from probabilistic call-by-value programs with procedures to Rabin’s probabilistic automata. The translation is fully abstract in that programs exhibit the same computational behaviour if and only if the corresponding automata are language-equivalent. Since probabilistic language equivalence is decidable, we can apply the translation to analyse the behaviour of probabilistic programs and protocols. We illustrate our approach on a number of case studies.     

Probability of seminal vesicle involvement in localized prostatic carcinoma. Significance in conformal radiotherapy

PURPOSE: The development of objective criteria for selecting patients for seminal vesicle irradiation on radical radiotherapy for prostate cancer will be important for successful planning of 3D conformal radiotherapy. MATERIALS AND METHODS: Based on morphometric studies from radical prostatectomy specimens, new imaging modalities with potential in the investigation of patients with gross seminal vesicle involvement and clinical factors with potential in the identification of patients with subclinical disease the development of objective guidelines is possible. RESULTS: Clinical tumor stage as determined by digital rectal examination, diagnostic tumor biopsy (Gleason Score), and pretherapy serum prostate-specific antigen value were significant factors for the probability of involvement of seminal vesicles. Studies show that seminal vesicle involvement is unlikely if the PSA is < 4 ng/ml or 4 to 10 ng/ml and Gleason Score < 7 and stage < or = T2b. In contrast, involvement of seminal vesicles is highly likely with levels above 20 ng/ml. In patients with PSA levels between 10 and 20 ng/ml and Gleason Score < 7 ultrasonographic findings with regard to tumor volume and localization will be useful to determine the extent of the target volume. For treatment planning a significant reduction in the volumes of irradiation to the rectum and bladder is evident when seminal vesicles were excluded. CONCLUSION: Prospective use of the objective criteria will be useful in the selection of patients for seminal vesicle involvement and should be an integral part in 3D conformal radiotherapy of prostate cancer.     

Expert system applications in software engineering

This paper presents an overview of research in expert systems and artificial intelligence as they relate to software engineering. The paper begins with a review of current thinking regarding the software process. This is followed by a discussion of artificial intelligence (AI) and the paradigms it uses. Six current projects are described: three are concerned with programming in the large and three with programming in the small. These six projects provide a representative sample of the AI research now underway in the software engineering domain. The paper concludes with some observations regarding when and how the concepts represented by these projects will be available for application to operational projects.     

Assignment of raw material and authentication of spirits by gas chromatography, hydrogen- and carbon-isotope ratio measurements I. Analytical methods and results of a study of commercial products

Gas chromatography and the determination of natural isotope ratios are powerful analytical methods which can be used to check the authenticity of alcoholic beverages and to detect any adulteration. To check the origin and the authenticity of commercial fruit spirits, whiskies, etc., 197 samples were analysed by gas chromatography, ²H-NMR and ¹³C isotope mass spectrometry. The discrimination between different varieties was demonstrated by bivariate and multivariate discriminant analysis using different concentrations of volatile compounds such as methanol, butan-1-ol, 2- and 3-methyl-butanol, benzaldehyde and hexanol as well as isotopic data like (D/H)_I, (D/H)_II and ¹³C/¹²C isotopomers of ethanol. The results show that by using multivariate discriminant analysis it is possible to distinguish not only between different groups of spirits, e.g. those made of stone-fruit, malaceous fruit, grain and corn, but also between individual varieties, such as cherry, plum, mirabelle and apple. If the detection of highly rectified ethyl alcohol of agricultural origin and the identification of its raw materials are required, then natural isotope ratios are the only discriminant analytical parameters available.