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71.
Tanja E. J. Vos Felix F. Lindlar Benjamin Wilmes Andreas Windisch Arthur I. Baars Peter M. Kruse Hamilton Gross Joachim Wegener 《Software Quality Journal》2013,21(2):259-288
During the past years, evolutionary testing research has reported encouraging results for automated functional (i.e. black-box) testing. However, despite promising results, these techniques have hardly been applied to complex, real-world systems and as such, little is known about their scalability, applicability, and acceptability in industry. In this paper, we describe the empirical setup used to study the use of evolutionary functional testing in industry through two case studies, drawn from serial production development environments at Daimler and Berner & Mattner Systemtechnik, respectively. Results of the case studies are presented, and research questions are assessed based on them. In summary, the results indicate that evolutionary functional testing in an industrial setting is both scalable and applicable. However, the creation of fitness functions is time-consuming. Although in some cases, this is compensated by the results, it is still a significant factor preventing functional evolutionary testing from more widespread use in industry. 相似文献
72.
Feng Mao James A. Gaunt Chu-Lin Cheng Say Kee Ong 《Canadian Metallurgical Quarterly》2011,137(2):137-145
Organic contaminants may permeate through plastic pipes in water distribution systems and adversely affect the quality of drinking water. In this study, we developed a microscopic visualization technique to investigate the permeation of common organic contaminants (benzene, toluene, ethylbenzene, xylene, and trichloroethene) through polyvinyl chloride (PVC) pipes. By observing the propagation of organic moving fronts in the pipe materials with a light microscope, the technique was able to predict the permeation breakthrough times through PVC pipes that were determined in the pipe-bottle test. The advance of an organic moving front was found to be linearly dependent on the square-root of time and the propagation rate increased with an increase in the external organic chemical activity. Permeation of organic mixtures into PVC pipes was found to be additive in proportion to the permeation rates and volume percents of each component. In combination with a 2-year pipe-bottle test for PVC pipes exposed to premium gasoline, mathematical extrapolations based on the microscopic visualization tests predicted that PVC pipe are likely to resist permeation by commercial gasoline for the service life of the pipe. 相似文献
73.
Chilin Li Xiangxin Guo Lin Gu Dominik Samuelis Joachim Maier 《Advanced functional materials》2011,21(15):2901-2905
Lithium fluoride thin films with various thicknesses have been grown on c‐plane sapphire substrates by radio‐frequency sputtering. The thin films are granular with a preferential [111] orientation of the grains. Thickness‐dependent measurements allow the separation of bulk and interface conductions. The normalized conductance decreases linearly with decreasing LiF layer thickness with a negative extrapolated intercept. DC polarization, AC impedance spectroscopy and electromotive force measurement indicate depletion of lithium ion vacancies as majority charge carriers and hence a negative space‐charge potential. A generalized Mott–Schottky approach within the model of heterogeneous doping fully explains the entire boundary defect chemistry. 相似文献
74.
Joachim von zur Gathen 《Applicable Algebra in Engineering, Communication and Computing》2011,22(3):165-185
A polynomial f (multivariate over a field) is decomposable if f=g °h{f=g circ h} with g univariate of degree at least 2. We determine the dimension (over an algebraically closed field) of the set of decomposables, and an approximation to their number over a finite field. The relative error in our approximations is exponentially decaying in the input size. 相似文献
75.
Joseph Berry Tonio Buonassisi David A. Egger Gary Hodes Leeor Kronik Yueh‐Lin Loo Igor Lubomirsky Seth R. Marder Yitzhak Mastai Joel S. Miller David B. Mitzi Yaron Paz Andrew M. Rappe Ilan Riess Boris Rybtchinski Oscar Stafsudd Vladan Stevanovic Michael F. Toney David Zitoun Antoine Kahn David Ginley David Cahen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(35):5102-5112
76.
Prof. Dr. Andreas Leson Gregor Englberger Daniel Hammer Stefan Makowski Carl‐Friedrich Meyer Michael Leonhard Hans‐Joachim Scheibe Volker Weihnacht 《真空研究与实践》2015,27(4):24-28
Diamond‐like carbon thin films enhance efficiency — laser arc deposition of ta‐C Rising prices for fossil fuels as well as the increasing effects of the climate change due to the emission of greenhouse gases reveal the necessity of saving energy. Low friction coatings have an enormous potential in saving energy. Carbon based coatings — named as DLC coatings — are especially well suited for low friction coatings. In particular hydrogen‐free tetrahedral amorphous carbon (ta‐C) coatings are of great interest due to their extraordinary low wear properties. In addition they show excellent low friction properties and especially in combination with specific lubricants the so‐called super low friction effect. For the deposition of ta‐C coatings PVD methods have to be applied instead of CVD methods as it is the case for conventional DLC coatings. We have developed a deposition method which is based on a pulsed arc steered by a laser (Laser‐Arc). This allows us to use large cathodes resulting in a high long‐term stability. Furthermore, the carbon plasma source can be combined with a filtering unit removing almost all droplets and particles, which usually are characteristic for an arc process. The resulting Laser‐Arc source allows for the deposition of smooth and virtually defect‐free ta‐C coatings with a competitive deposition rate. 相似文献
77.
Nurdan Sayın 《Bulletin of Engineering Geology and the Environment》2013,72(3-4):579-587
This study was conducted to investigate the radioactive potential hazard of granite, which is widely used as building material in Turkey. Natural radiation levels of 18 various, globally-distributed industrial granite samples imported by Turkey, were analyzed using gamma-ray spectrometer. The results are compared with the formerly published findings of granite samples from Turkey. Radioactivity levels of 238U, 232Th, and 40K natural radioactive series elements of the selected 18 specimens were measured, which were from 2.4 ± 0.5 to 88.8 ± 3.6 Bq kg?1 for 238U, from 2.4 ± 0.7 to 273 ± 0.9 Bq kg?1 for 232Th, and from 169 ± 24 to 1,479 ± 94 Bq kg?1 for 40K. Radium equivalent activities (Raeq) were calculated for the granite samples to assess their radiation hazards in the construction of dwellings. The Raeq values of granite samples varied in the range of 39.05–570 Bq kg?1, only one sample exceeded the safe limit value of 370 Bq kg?1 set by the OECD-NEA (Nuclear Energy Agency. Exposure to radiation from natural radioactivity in building materials. Report by NEA Group of Experts 1979). Absorbed dose rates in air were found between 18.74 and 261 nGy h?1 and radiogenic heat production values were calculated in the range of 0.45–6.53 μW m?3. All rock samples used in this study were also analysed mineralogically and defined their compositions. 相似文献
78.
79.
Jong-Min Park Mi Yeon Kim Joachim Jose Min Park 《International journal of molecular sciences》2022,23(1)
A regenerable immunoaffinity layer comprising covalently immobilized orientation-controlled antibodies was developed for use in a surface plasmon resonance (SPR) biosensor. For antibody orientation control, antibody-binding Z-domain-autodisplaying Escherichia coli (E. coli) cells and their outer membrane (OM) were utilized, and a disuccinimidyl crosslinker was employed for covalent antibody binding. To fabricate the regenerable immunoaffinity layer, capture antibodies were bound to autodisplayed Z-domains, and then treated with the crosslinker for chemical fixation to the Z-domains. Various crosslinkers, namely disuccinimidyl glutarate (DSG), disuccinimidyl suberate (DSS) and poly (ethylene glycol)-ylated bis (sulfosuccinimidyl)suberate (BS(PEG)5), were evaluated, and DSS at a concentration of 500 μM was confirmed to be optimal. The E. coli-cell-based regenerable HRP immunoassay was evaluated employing three sequential HRP treatment and regeneration steps. Then, the Oms of E. coli cells were isolated and layered on a microplate and regenerable OM-based HRP immunoassaying was evaluated. Five HRP immunoassays with four regeneration steps were found to be feasible. This regenerable, covalently immobilized, orientation-controlled OM-based immunoaffinity layer was applied to an SPR biosensor, which was capable of quantifying C-reactive protein (CRP). Five regeneration cycles were repeated using the demonstrated immunoaffinity layer with a signal difference of <10%. 相似文献
80.
Mario Fleischer Lukas Schumann Anne Hartmann Reuben Scott Walker Liliana Ifrim Dorothea von Zadow Jonas Lüske Joachim Seybold Martin Kriegel Dirk Mürbe 《Journal of the Royal Society Interface》2022,19(187)
Speaking and singing are activities linked to increased aerosol particle emissions from the respiratory system, dependent on the utilized vocal intensity. As a result, these activities have experienced considerable restrictions in enclosed spaces since the onset of the COVID-19 pandemic due to the risk of infection from the SARS-CoV-2 virus, transmitted by virus-carrying aerosols. These constraints have affected public education and extracurricular activities for children as well, from in-person music instruction to children’s choirs. However, existing risk assessments for children have been based on emission measurements of adults. To address this, we measured the particle emission rates of 15 pre-adolescent children, all eight to ten years old, with a laser particle counter for the test conditions: breathing at rest, speaking, singing and shouting. Compared with values taken from 15 adults, emission rates for breathing, speaking and singing were significantly lower for children. Particle emission rates were reduced by a factor of 4.3 across all conditions, whereas emitted particle volume rates were reduced by a factor of 4.8. These data can supplement SARS-CoV-2 risk management scenarios for various school and extracurricular settings. 相似文献