Travelling salesman problem tools for microcomputers

The problem of determining minimum total distance to be travelled by a salesman, who is to visit given cities each only once (i.e. the travelling salesman problem) is one of the most studied problems in computational mathematics. Finding an exact solution is not only intractably difficult, but also exceedingly costly. However, we implemented efficient optimal algorithms for both symmetric and asymmetric distance problems. The programs implemented can solve problems up to 180 cities in reasonable computer time.     

Three-Phase Induction Generator for Single-Phase Line

Hydroelectric generators of less than 20 kilowatts can be in remote areas served only by a single-phase line. For high efficiency and low cost, a three-phase induction generator should be used. This three-phase generator can operate with balanced voltages and currents when the ``phase-splitting' circuit uses two capacitors connetted to two different single-phase voltage sources.     

Electrical characterization of megabit DRAMs. 11. Internal testing

For pt.I. see ibid., vol.8, no.3, p.36-43 (1991). Contactless tools for testing inside dynamic RAMs, including hot-spot detection, emission microscopy, scanning laser microscopy, and submicron electron beam testing, are described. Basic principles and experimental setups are described. The utility of the techniques is assessed     

Chicken acidic leucine-rich EGF-like domain containing brain protein (CALEB), a neural member of the EGF family of differentiation factors, is implicated in neurite formation

Chicken acidic leucine-rich EGF-like domain containing brain protein (CALEB) was identified by combining binding assays with immunological screens in the chicken nervous system as a novel member of the EGF family of differentiation factors. cDNA cloning indicates that CALEB is a multidomain protein that consists of an NH2-terminal glycosylation region, a leucine-proline-rich segment, an acidic box, a single EGF-like domain, a transmembrane, and a short cytoplasmic stretch. In the developing nervous system, CALEB is associated with glial and neuronal surfaces. CALEB is composed of a 140/130-kD doublet, an 80-kD band, and a chondroitinsulfate-containing 200-kD component. The latter two components are expressed in the embryonic nervous system and are downregulated in the adult nervous system. CALEB binds to the extracellular matrix glycoproteins tenascin-C and -R. In vitro antibody perturbation experiments reveal a participation of CALEB in neurite formation in a permissive environment.     

The distribution of HBV, HCV and HGV among livers with fulminant hepatic failure of different aetiology

BACKGROUND/AIMS: The aim of the study was to assess the impact factor of HCV and HGV in fulminant hepatic failure. METHODS: The 5'-untranslated regions of HCV RNA and HGV RNA and a segment of the core antigen sequence of HBV were amplified after extracting the nucleic acids from snap-frozen tissue aliquots from explanted livers of 26 consecutive patients undergoing orthotopic liver transplantation for fulminant hepatic failure preoperatively diagnosed as either autoimmune (n=2), HAV/HBV (n=8), toxic (n=4) or aetiologically unknown (n=12). RESULTS: HCV RNA was detected in five of 26 (19.2%) livers with fulminant hepatic failure. All five HCV RNA-positive livers belonged to the group of non-toxic, non-autoimmune liver failure (n=20), three of them were found in the group of liver failure with unknown aetiology (n=12) and two in the group of HBV-associated liver failure (n=7), making an HCV incidence of 25%, 25% and 28.6%, in the different groups, respectively. HGV RNA was detected in 10 of 17 (58.8%) explants and in all four groups of fulminant hepatic failure as defined preoperatively. HBV DNA was identified in six livers of 26 patients (23.1%) with fulminant hepatic failure. Neither HCV RNA nor HBV DNA was detected in the livers of patients with toxic or autoimmune fulminant hepatic failure. CONCLUSIONS: These results indicate that HBV and HCV, but not HGV, play an aetiologic role in fulminant hepatic failure. HCV-positive cases were concentrated either in the group of otherwise unexplained fulminant hepatic failure or in the group of HBV fulminant hepatic failure. HGV-positive cases, on the other hand, were found within all four preoperatively defined groups, indicating a role as cofactor rather than as single aetiologic agent.     

Review of Forms of feeling: The heart of psychotherapy.

Reviews the book, Forms of feeling: The heart of psychotherapy by Robert F. Hobson. Robert Hobson calls this book his autobiography as a therapist. As such it provides interesting glimpses into some of his more meaningful sessions with clients, illuminating his approach to therapy and enabling the reader to see a master therapist at work. Hobson also presents a new method of therapy, which he calls the conversational model. On this level, his book is considerably less satisfying. Hobson succinctly outlines the general principles of the conversational model and basic skills required of the therapist, but in so doing offers essentially little new information, however valid the points may be. According to Hobson, the conversational model is designed for clients whose problems arise from disturbances in their significant relationships, and those problems are best solved not by talking about them but by being in a relationship such as therapy that provides "a special kind of friendship." Hobson puts great stress on the use of metaphorical language in therapy and learning how to use the language of art as well as of science. He relies heavily on literary quotations, prefacing each section with one or two, and liberally interspersing many more within the pages of text. The net result is not so much illuminating as it is wearisome, and the general tone is slightly pretentious and, when Hobson addresses his "dear Reader" directly, somewhat condescending. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Something completely different: Informatik und Sport

Ohne Zusammenfassung     

Heat transfer mechanisms in gas fluidized beds. Part 3: Heat transfer in circulating fluidized beds

Part 1 of this contribution reported on the effects of system properties on heat transfer between heating or cooling surfaces and bubbling fluidized beds. This investigation produced four correlations which define the respective maximum heat transfer. Part 2 of this study suggests that the heat transfer between exchanger surfaces and bubbling fluidized beds depends on superficial gas velocity, expressed as dimensionless excess gas velocity. The present paper shows that heat transfer coefficients in circulating fluidized beds can be predicted by evaluation of a state diagram, which combines three dimensionless groups: Nusselt number, Archimedes number and a dimensionless pressure gradient. A comparison of coal combustion experiments with own cold model measurements indicates that the radiative component of heat transfer coefficients is only evident at very low dimensionless pressure gradients.     

On confluence versus strong confluence for one-rule trace-rewriting systems

Examples of one-rule trace-rewriting systems are given that are confluent but not strongly confluent. This contrasts with the situation for one-rule string-rewriting systems as well as with the situation for one-rule commutative string-rewriting systems.     

Head-to-head polymers: 33. Bromination of cis-1,4-polybutadiene to head-to-head poly(vinyl bromide)

Cis-1,4-polybutadiene (PB) in a 0.5% solution of a solvent mixture of dichloromethane and 1,2-dibromoethane or tetrahydrofuran was quantitatively brominated with elemental bromine at 0°C under careful exclusion of oxygen to head-to-head poly(vinyl bromide). Partially brominated PB has a structure of random or block sequences of butadiene units in the polymer depending on the bromination solvent but shows no stereospecificity in the CHBrCHBr-dyads. Partially brominated PB with block structure showed a microphase-separated morphology over a wide range of composition. Microphase separation is less pronounced for the more random structure of butadiene units. I.r and ¹³C n.m.r. spectroscopy of the partially brominated PB was used to follow the progress of the bromination.