A heat-flux based “building block” approach for solving heat conduction problems

A numerical approximation of the Green’s function equation based on a heat-flux formulation is given. It is derived by assuming as a functional form of the surface heat flux a stepwise variation with space and time. The obtained approximation is very important in investigation of the inverse heat conduction problems (IHCPs) because it gives a convenient expression for the temperature in terms of the heat flux components. Additionally, it is very important for the unsteady surface element (USE) method which is a modern boundary discretization method. Green’s function approximate solution equation (GFASE) also creates ‘naturally’ fixed groups or modules of work elements called “building blocks” that may be added together to obtain space and time values of temperature. In the current case, they are subject to a partial heating by an applied surface heat flux. The “building block” solution can be derived by using the various analytical and numerical approaches available in heat conduction literature though the exact analysis is preferable, as discussed in the text. Poorly-convergent series deriving from Green’s functions approach are replaced by closed-form algebraic solutions.     

SECULAR SEASONS: LONG-RUN TRENDS IN SPATIAL-TEMPORAL SOCIOECONOMIC BEHAVIOR

ABSTRACT This paper proposes an explanation of unbalanced regional growth and regional inequalities based on the view that human behaviour is motivated either to reduce the physiological state of arousal or to increase it. While arousal reduction is the basis of conventional economic analysis arousal augmentation is seldom considered. This paper argues that arousal augmentation motivates society to seek technological and socioeconomic innovations that trigger economic progress. The mechanism for this progress is seen as a synthesis of spatial growth poles and temporal long waves.     

Organically modified silica sol-mediated capillary electrophoresis

We describe in this paper the use of ormosil (organically modified silica) sols as additives to the run buffer for selectivity manipulations between solutes in capillary electrophoresis. CE systems that contain sol additives in the run buffer can be thought of as pseudocapillary electrochromatography. Three sols based on different types of silanes were studied. Methyltrimethoxysilane (MTMOS)-based sol was found to improve selectivities between various aromatic acids. Aminopropyltrimethoxysilane (APS) sol interacts differently with structural isomers of aromatic acids than does MTMOS. At low pH with APS sol in the run buffer, neutral solutes can be separated, as well. The separation of the neutral solutes seems to be facilitated by the formation of hydrogen bonds between the solutes and the APS sol. APS and N-[3-(trimethoxysilyl)propyl]-ethylenediamine (EDAS) affect the separation of the same compounds differently, thus indicating that even small changes of the functional groups of the sol have pronounced effect on the interactions between the sols and the solutes.     

Comparative evaluation of platforms for parallel Ant Colony Optimization

The rapidly growing field of nature-inspired computing concerns the development and application of algorithms and methods based on biological or physical principles. This approach is particularly compelling for practitioners in high-performance computing, as natural algorithms are often inherently parallel in nature (for example, they may be based on a “swarm”-like model that uses a population of agents to optimize a function). Coupled with rising interest in nature-based algorithms is the growth in heterogenous computing; systems that use more than one kind of processor. We are therefore interested in the performance characteristics of nature-inspired algorithms on a number of different platforms. To this end, we present a new OpenCL-based implementation of the Ant Colony Optimization algorithm, and use it as the basis of extensive experimental tests. We benchmark the algorithm against existing implementations, on a wide variety of hardware platforms, and offer extensive analysis. This work provides rigorous foundations for future investigations of Ant Colony Optimization on high-performance platforms.     

Effects of fiber from tropical corn and forage sorghum silages on intake, digestion, and performance of lactating dairy cows

Tropical corn silage was compared with sorghum silage as a basal forage in the diets of high producing dairy cows. Sorghum and tropical corn silages were each included in place of ground corn at incremental concentrations in the experimental diets. Eight separate diets were fed, four diets containing each silage ranging in forage neutral detergent fiber (NDF) from approximately 25 to 31% and ranging in total NDF from approximately 41 to 45%. Diets were arranged in a 2 x 4 factorial design and were fed to lactating cows (n = 24; pretrial mean milk production = 39 kg/d; body weight = 656 kg; and days in milk = 81). As concentrations of dietary NDF increased, intake and milk production decreased linearly. The impact of dietary NDF on intake was greater for diets based on tropical corn silage than for diets based on sorghum silage. Energy intake and milk production were reduced, but cows consumed more fiber when challenged with higher dietary concentrations of fiber. The in vitro rate and extent of digestion of dietary samples were correlated with intake response. The rate of in vitro fiber digestion was slower for samples that contained tropical corn silage than for samples that contained sorghum silage. In vivo digestibility measurements were influenced by intake and dietary composition. Results of this trial indicated that sorghum silage can have equal or slightly greater nutritional value than tropical corn silage when these forages are fed at equal concentrations of dietary fiber.     

Tight Bounds for Distributed Minimum-Weight Spanning Tree Verification

This paper introduces the notion of distributed verification without preprocessing. It focuses on the Minimum-weight Spanning Tree (MST) verification problem and establishes tight upper and lower bounds for the time and message complexities of this problem. Specifically, we provide an MST verification algorithm that achieves simultaneously $\tilde{O}(m)$ messages and $\tilde{O}(\sqrt{n} + D)$ time, where m is the number of edges in the given graph G, n is the number of nodes, and D is G’s diameter. On the other hand, we show that any MST verification algorithm must send $\tilde{\varOmega}(m)$ messages and incur $\tilde{\varOmega}(\sqrt{n} + D)$ time in worst case. Our upper bound result appears to indicate that the verification of an MST may be easier than its construction, since for MST construction, both lower bounds of $\tilde{\varOmega}(m)$ messages and $\tilde{\varOmega}(\sqrt{n} + D)$ time hold, but at the moment there is no known distributed algorithm that constructs an MST and achieves simultaneously $\tilde{O}(m)$ messages and $\tilde{O}(\sqrt{n} + D)$ time. Specifically, the best known time-optimal algorithm (using ${\tilde{O}}(\sqrt {n} + D)$ time) requires O(m+n ^3/2) messages, and the best known message-optimal algorithm (using ${\tilde{O}}(m)$ messages) requires O(n) time. On the other hand, our lower bound results indicate that the verification of an MST is not significantly easier than its construction.     

Toward more localized local algorithms: removing assumptions concerning global knowledge

Numerous sophisticated local algorithm were suggested in the literature for various fundamental problems. Notable examples are the MIS and $(\Delta +1)$ -coloring algorithms by Barenboim and Elkin (Distrib Comput 22(5–6):363–379, 2010), by Kuhn (2009), and by Panconesi and Srinivasan (J Algorithms 20(2):356–374, 1996), as well as the $O\mathopen {}(\Delta ^2)$ -coloring algorithm by Linial (J Comput 21:193, 1992). Unfortunately, most known local algorithms (including, in particular, the aforementioned algorithms) are non-uniform, that is, local algorithms generally use good estimations of one or more global parameters of the network, e.g., the maximum degree $\Delta $ or the number of nodes $n$ . This paper provides a method for transforming a non-uniform local algorithm into a uniform one. Furthermore, the resulting algorithm enjoys the same asymptotic running time as the original non-uniform algorithm. Our method applies to a wide family of both deterministic and randomized algorithms. Specifically, it applies to almost all state of the art non-uniform algorithms for MIS and Maximal Matching, as well as to many results concerning the coloring problem (In particular, it applies to all aforementioned algorithms). To obtain our transformations we introduce a new distributed tool called pruning algorithms, which we believe may be of independent interest.     

In vivo performances of pure Zn and Zn–Fe alloy as biodegradable implants

The disadvantage of current biodegradable metals such as Mg and Fe is the release of hydrogen gas in vivo that can cause gas embolism and the production of voluminous iron oxide that can cause inflammation, respectively. Such considerations have turned focus towards Zn as an alternative. This is based on the fact that Zn plays a crucial role in many physiological processes, as well as potentially being biocompatible and capable of with biodegradation. As such, the purpose of the present study was to evaluate the in vivo performance of pure Zinc and Zn–2%Fe implants. The use of iron as an alloying element was aimed at accelerating the corrosion rate of pure zinc by a micro-galvanic effect so as to maintain the post-implantation biodegradation characteristics of the implant. In vivo assessment was carried out using cylindrical disks implanted in the back midline of 16 male Wistar rats for up to 24 weeks. Post-implantation evaluation included monitoring the well-being of rats, weekly examination of hematological parameters: serum Zn levels, red and white blood cell counts and hemoglobin levels, X-ray radiography, histological analysis and corrosion rate assessment. The results obtained in terms of well-being, hematological tests and histological analysis of the rats indicate that the in vivo behavior of pure Zn and Zn–2%Fe implants was adequate and in line with the results obtained by the control group containing inert Ti–6Al–4V alloy implants. The corrosion rate of Zn–2%Fe alloy in in vivo conditions was relatively increased compared to pure Zn due to micro-galvanic corrosion.

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Preparation for cesarean delivery: A multicomponent analysis of treatment outcome.

We evaluated the effects of sensory information about cesarean delivery on prenatal maternal anxiety and on recovery subsequent to delivery by cesarean section. The 42 participants were recruited from a population of obstetric patients. Patients were assigned to either treatment or control groups and identified as sensitizers or repressors. Treatment groups viewed a slide/tape program presenting procedures involved in cesarean delivery. Control groups viewed a program presenting neutral information. Prepared patients classified as sensitizers showed less physiologic arousal during surgery and enhanced postsurgical recovery. Physiologic and self-report measures of anxiety indicated that the intervention itself was not a stressful event. The relations among arousal, subjective anxiety, coping styles, and treatment outcome are discussed and recommendations are made for further investigation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential weighting of common and distinctive components.

We investigated possible explanations of the finding that the relative weight (W) of common components in similarity judgments is higher for verbal than for pictorial stimuli. A serial presentation of stimulus components had no effect on verbal stimuli; it increased the impact of both common and distinctive components of pictorial stimuli but did not affect their relative weight. On the other hand, W was increased by manipulations that reduced the cohesiveness of composite pictures, such as separating, scrambling, and mixing their components. Furthermore, W was decreased by manipulations that enhanced the cohesiveness of composite verbal stimuli by imposing structure on their components. Verbal and pictorial representations of the same stimuli yielded no systematic differences in W. (PsycINFO Database Record (c) 2010 APA, all rights reserved)