Showing papers by "University of Maribor published in 2005"

When and how to develop domain-specific languages

Abstract: Domain-specific languages (DSLs) are languages tailored to a specific application domain. They offer substantial gains in expressiveness and ease of use compared with general-purpose programming languages in their domain of application. DSL development is hard, requiring both domain knowledge and language development expertise. Few people have both. Not surprisingly, the decision to develop a DSL is often postponed indefinitely, if considered at all, and most DSLs never get beyond the application library stage.Although many articles have been written on the development of particular DSLs, there is very limited literature on DSL development methodologies and many questions remain regarding when and how to develop a DSL. To aid the DSL developer, we identify patterns in the decision, analysis, design, and implementation phases of DSL development. Our patterns improve and extend earlier work on DSL design patterns. We also discuss domain analysis tools and language development systems that may help to speed up DSL development. Finally, we present a number of open problems.

A model for integrated assessment of sustainable development

Abstract: The focus of the paper is on consideration of how to use indicators to monitor sustainable development in a relevant and useful manner. Integrated information on sustainable development of a company is very essential for decision-making since it is very difficult to evaluate the performance of the company on the ground of too many indicators. The objective of the work was to design a model for obtaining a composite sustainable development index (ICSD) in order to track integrated information on economic, environmental, and social performance of the company with time. Normalized indicators were associated into three sustainability sub-indices and finally composed into an overall indicator of a company performance. This was applied by determining the impact of individual indicator to the overall sustainability of a company using the concept of analytic hierarchy process. The demonstration of the model used data for a case study company, Henkel, and a set of sustainable development indicators that were classified using the currently most widely accepted approach of the Global Reporting Initiative (GRI). Case study was used to measure ICSD and sustainability sub-indices of the company over the time interval of 6 years. Interpretation of results is given and the utility of ICSD with its relevance for decision-making is pointed out. Using a case study, the paper demonAbbreviations: AHP, analytic hierarchy process; AIChE, American Institute of Chemical Engineers; COD, chemical oxygen demand; CWRT, Center for Waste Reduction Technologies; EMAS, eco-management and auditing scheme; EUR, euro; GRI, Global Reporting Initiative; IChemE, Institution of Chemical Engineers; ISO, International Organization for Standardization; SD, sustainable development; UP, unit of production; VOC, volatile organic compound; WBCSD, World Business Council for Sustainable Development; WCED, World Commission on Environment and Development

The dynamics of human gait

Abstract: We analyse the dynamics of human gait with simple nonlinear time series analysis methods that are appropriate for undergraduate courses. We show that short continuous recordings of the human locomotory apparatus possess properties typical of deterministic chaotic systems. To facilitate interest and enable the reproduction of presented results, as well as to promote applications of nonlinear time series analysis to other experimental systems, we provide user-friendly programs for each implemented method. Thus, we provide new insights into the dynamics of human locomotion, and make an effort to ease the inclusion of nonlinear time series analysis methods into the curriculum at an early stage of the educational process.

Observation of a Near-Threshold ωJ/ψ Mass Enhancement in Exclusive B→KωJ/ψ Decays

Abstract: Reference EPFL-ARTICLE-154584doi:10.1103/PhysRevLett.94.182002View record in Web of Science Record created on 2010-11-05, modified on 2017-12-10

Observation of B+ ---> K(1)(1270)+ gamma

Abstract: We report the observation of the radiative decay B+-->K1(1270)(+) gamma using a data sample of 140 fb(-1) taken at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- collider. We find the branching fraction to be B(B+-->K1(1270)(+)gamma)=(4.3+/-0.9(stat.)+/-0.9(syst.))x10(-5) with a significance of 7.3sigma. We find no significant signal for B+-->K1(1400)(+)gamma and set an upper limit B(B+-->K1(1400)(+)gamma) K+pi+pi-gamma and B0-->K0pi+pi-gamma in the mass range 1 GeV/c(2)

Detecting chaos from a time series

Abstract: The chaotic behaviour of a driven resonant circuit is studied directly from the experimental data. We use basic nonlinear time series analysis methods that are appropriate for undergraduate courses. Mutual information and false nearest neighbours are explained in detail, and used to obtain the best possible attractor reconstruction. For the reconstructed attractor, a determinism test is performed and the largest Lyapunov exponent is calculated. We show that the largest Lyapunov exponent is positive, which is a strong indicator for the chaotic behaviour of the system. To help the reader reproduce our results and to facilitate further applications on other experimental systems, we provide user-friendly programs with graphical interface for each implemented method on our Web page.

Spatial coherence resonance in excitable media.

Abstract: We study the phenomenon of spatial coherence resonance in a two-dimensional model of excitable media with FitzHugh-Nagumo local dynamics. In particular, we show that there exists an optimal level of additive noise for which an inherent spatial scale of the excitable media is best pronounced. We argue that the observed phenomenon occurs due to the existence of a noise robust excursion time that is characteristic for the local dynamics whereby the diffusion constant, representing the rate of diffusive spread, determines the actual resonant spatial frequency. Additionally, biological implications of presented results in the field of neuroscience are outlined.

Laundry wastewater treatment using coagulation and membrane filtration

Abstract: This paper presents the results obtained from laundry wastewater treatment using conventional methods namely precipitation/coagulation and the flocculation process with adsorption on granular-activated carbon (GAC) and an alternative method, membrane filtrations, namely ultrafiltration (UF) and reverse osmosis (RO). Chemical analyses showed that parameter values of untreated wastewater like temperature, pH, sediment substances, total nitrogen and phosphorous, COD, BOD5, and the amount of anion surfactants had been exceeded in regard to Slovenian regulation. These regulations can be used as requirements for wastewater reuse and make treated wastewater an available source for the existing water supply. The study of conventional treatment was based on a flocculation with Al2(SO4)3·18H2O and adsorption on GAC. Membrane filtrations were studied on a pilot wastewater treatment plant: ultrafiltration (UF) and reverse osmosis (RO) units. The membranes used in this experiment were ceramic UF membrane and spiral wounded – polyethersulfone – RO membranes. The quality of the wastewater was improved by both methods and the specifications of a concentration limit for emission into water were confirmed. The disadvantage of GAC is that there is no possibility of any kind of selection, which is essential for recycling and re-use, while permeate coming from RO met the required regulation as well as requirements for reusing in washing process. However, the economical analyses showed that the membrane filtrations are more expensive compared to the GAC treatment process.

Improved measurement of the electroweak penguin process B→Xs+-

Abstract: Reference EPFL-ARTICLE-154446doi:10.1103/PhysRevD.72.092005View record in Web of Science Record created on 2010-11-05, modified on 2017-05-12

All-fiber high-sensitivity pressure sensor with SiO~2 diaphragm

Abstract: The design and fabrication of a miniature fiber Fabry–Perot pressure sensor with a diameter of 125??m are presented. The essential element in the process is a thin SiO2 diaphragm that is fusion spliced at the hollow end of an optical fiber. Good repeatability and high sensitivity of the sensor are achieved by on-line tuning of the diaphragm thickness during the sensor fabrication process. Various sensor prototypes were fabricated, demonstrating pressure ranges of from 0 to 40 kPa to 0 to 1 MPa. The maximum achieved sensitivity was 1.1?rad?40?kPa at 1550 nm, and a pressure resolution of 300 Pa was demonstrated in practice. The presented design and fabrication technique offers a means of simple and low-cost disposable pressure sensor production.

Dalitz analysis of the three-body charmless decays B+→K+π+π- and B+→K+K+K-

Abstract: We report results on the Dalitz analysis of three-body charmless B+ -> K+ pi(+) pi(-) and B+-> K+ K+ K- decays based on a 140 fb(-1) data sample collected with the Belle detector. Measurements of branching fractions for quasi-two-body decays to scalar-pseudoscalar states: B+ -> f(0)(980)K+, B+ -> K-0(*)(1430)(0)pi(+), and to vector-pseudoscalar states: B+ -> K-*(892)(0)pi(+), B+ -> rho(0)K(+), B+ -> phi K+ are presented. Upper limits on decays to some pseudoscalar-tensor final states are reported. We also report the measurement of the B+ -> chi(c0)K(+) branching fraction in two chi(c0) decays channels: chi(c0) -> pi(+)pi(-) and chi(c0) -> K+K-.

Disodium guanosine 5'-monophosphate self-associates into nanoscale cylinders at pH 8: a combined diffusion NMR spectroscopy and dynamic light scattering study.

Abstract: We report a combined NMR and dynamic light scattering (DLS) study on the size of supramolecular structures formed by disodium guanosine 5‘-monophosphate, Na2(5‘-GMP), at pH 8. In general, two distinct types of aggregate species are present in an aqueous solution of Na2(5‘-GMP). One type consists of stacking 5‘-GMP monomers, and the other contains stacking G-quartets. Both types of aggregates can be modeled as rodlike cylinders. The cylinder diameter is 10 and 26 A for monomer aggregates and quartet aggregates, respectively. For Na2(5‘-GMP) concentrations between 18 and 34 wt %, the cylinders formed by stacking G-quartets have an average length between 8 and 30 nm, corresponding to a stack of ∼24−87 G-quartets. These nanoscale aggregates are significantly larger than what had previously been believed for Na2(5‘-GMP) self-association at pH 8. The length of both types of 5‘-GMP aggregates was found to increase with Na2(5‘-GMP) concentration but was insensitive to the added NaCl in solution. While the aggrega...

Spatial decoherence induced by small-world connectivity in excitable media

Abstract: We study effects of different network topologies on the noise-induced pattern formation in a two-dimensional model of excitable media with FitzHugh–Nagumo local dynamics. In particular, we show that the introduction of long-range couplings induces decoherence of otherwise coherent noise-induced spatial patterns that can be observed by regular connectivity of spatial units. Importantly, already a small fraction of long-range couplings is sufficient to destroy coherent pattern formation. We argue that the small-world network topology destroys spatial order due to the lack of a precise internal spatial scale, which by regular connectivity is given by the coupling constant and the noise robust excursion time that is characteristic for the local dynamics. Additionally, the importance of spatially versus temporally ordered neural network functioning is discussed.

Miniature fiber-optic pressure sensor with a polymer diaphragm

Abstract: The fabrication and experimental investigation of a miniature optical fiber pressure sensor for biomedical and industrial applications are described. The sensor measures only 125 µm in diameter. The essential element is a thin polymer diaphragm that is positioned inside the hollow end of an optical fiber. The cavity at the fiber end is made by a simple and effective micromachining process based on wet etching in diluted HF acid. Thus a Fabry–Perot interferometer is formed between the inner fiber–cavity interface and the diaphragm. The fabrication technique is described in detail. Different sensor prototypes were fabricated upon 125 µm-diameter optical fiber that demonstrated pressure ranges from 0 to 40 and from 0 to 1200 kPa. A resolution of less than 10 Pa was demonstrated in practice. The fabrication technique presented facilitates production of simple and low-cost disposable pressure sensors by use of materials with that ensure the required biocompatibility.

Enzymatic reactions in dense gases

Abstract: The developments on applications of supercritical fluids as alternative solvents for biocatalytic processes that have taken place over the past two decades have been reviewed. An overview of process parameters influencing enzyme activity and stability, the influence of process parameters on reaction rates and productivity are presented. Applications of various types of reactors for enzymatic reaction in dense fluids, limitations of using enzymes as biocatalyst in supercritical fluids as well as future trends are presented. Main advantages of using dense gases as solvents for biocatalyzed reactions are the tunability of solvent properties and simple down stream processing features that can be readily combined with other unit operations. Although many enzymes are stable in supercritical fluids (SCFs) one should pay considerable attention to finding the correct reaction conditions for each substrate/enzyme/SCF system. One of the persistent problems is the instability and deactivation of enzymes under pressure and temperature. At present the most stable enzymes are hydrolases (lipases and esterases) for which pressure effect is lower than temperature deactivation.

Acrylic Acid “Reversed” PolyHIPEs

Abstract: An oil-in-water high internal phase emulsion I consisting of acrylic acid, water, and a crosslinker (N,N'-methylene bisacrylamide) as the water phase, and toluene as the oil phase was successfully stabilised to sustain thermal initiation of radical polymerisation resulting in porous open-cellular monolithic material. The type of initiator used influenced the average pore size ranging from approx. 708 nm to approx. 1 087 nm, as determined by mercury porosimetry.

Application of measurements of transepithelial electrical resistance of intestinal epithelial cell monolayers to evaluate probiotic activity.

Abstract: Among five potentially probiotic lactobacilli investigated, Lactobacillus plantarum MF1298 and Lactobacillus salivarius DC5 showed the highest increase in the transepithelial electrical resistance (TER) of polarized monolayers of Caco-2 cells, and this increase was shown to be dose dependent. Furthermore, preincubation with MF1298 attenuated a decrease in TER induced by Listeria monocytogenes.

A novel type of proximity focusing RICH counter with multiple refractive index aerogel radiator

Abstract: A proximity focusing ring imaging Cherenkov detector, with the radiator consisting of two or more aerogel layers of different refractive indices, has been tested in 1 – 4 GeV / c pion beams at KEK. Essentially, a multiple refractive index aerogel radiator allows for an increase in Cherenkov photon yield on account of the increase in overall radiator thickness, while avoiding the simultaneous degradation in single photon angular resolution associated with the increased uncertainty of the emission point. With the refractive index of consecutive layers suitably increasing in the downstream direction, one may achieve overlapping of the Cherenkov rings from a single charged particle. The impact of the observed improvement on the π / K separation at the upgraded Belle detector is discussed.

Nonlinear time series analysis of the human electrocardiogram

Abstract: We analyse the human electrocardiogram with simple nonlinear time series analysis methods that are appropriate for graduate as well as undergraduate courses. In particular, attention is devoted to the notions of determinism and stationarity in physiological data. We emphasize that methods of nonlinear time series analysis can be successfully applied only if the studied data set originates from a deterministic stationary system. After positively establishing the presence of determinism and stationarity in the studied electrocardiogram, we calculate the maximal Lyapunov exponent, thus providing interesting insights into the dynamics of the human heart. Moreover, to facilitate interest and enable the integration of nonlinear time series analysis methods into the curriculum at an early stage of the educational process, we also provide user-friendly programs for each implemented method.

Observation of an isotriplet of excited charmed baryons decaying to Λ c + π

Abstract: Reference EPFL-ARTICLE-154564doi:10.1103/PhysRevLett.94.122002View record in Web of Science Record created on 2010-11-05, modified on 2017-12-10