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61.
62.
Bayesian networks (BN) have been used for decision making in software engineering for many years. In other fields such as bioinformatics, BNs are rigorously evaluated in terms of the techniques that are used to build the network structure and to learn the parameters. We extend our prior mapping study to investigate the extent to which contextual and methodological details regarding BN construction are reported in the studies. We conduct a systematic literature review on the applications of BNs to predict software quality. We focus on more detailed questions regarding (1) dataset characteristics, (2) techniques used for parameter learning, (3) techniques used for structure learning, (4) use of tools, and (5) model validation techniques. Results on ten primary studies show that BNs are mostly built based on expert knowledge, i.e. structure and prior distributions are defined by experts, whereas authors benefit from BN tools and quantitative data to validate their models. In most of the papers, authors do not clearly explain their justification for choosing a specific technique, and they do not compare their proposed BNs with other machine learning approaches. There is also a lack of consensus on the performance measures to validate the proposed BNs. Compared to other domains, the use of BNs is still very limited and current publications do not report enough details to replicate the studies. We propose a framework that provides a set of guidelines for reporting the essential contextual and methodological details of BNs. We believe such a framework would be useful to replicate and extend the work on BNs. 相似文献
63.
Experience with continuous venovenous hemodiafiltration in four newborns: A case series and review of the literature 下载免费PDF全文
Ali Ulas Tugcu Asli Kantar Aslihan Abbasoglu Ayse Ecevit Aylin Tarcan Esra Baskn 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(4):E59-E62
When conventional methods for treating complicated problems such as acute and chronic renal failure or metabolic diseases fail, the therapy of choice is peritoneal dialysis (PD) in neonatal period. However, in cases that involve technical difficulties, such as bulky lesions in the abdomen or complications from previous abdominal surgeries, it is not always possible to place a peritoneal catheter. In such situations, continuous venovenous hemodiafiltration (CVVHDF) can be effective. This case series presents our experience in 2013 with the administration of CVVHDF to four patients in our neonatal intensive care unit who could not undergo PD for various reasons. 相似文献
64.
This investigation is based on the production of lightweight, heat-insulating, water-resistant or water-repellent materials from lightweight aggregates, such as pumice and/or expanded perlite, without using cement or plaster as a binder. The results of this investigation reveal that a H3PO4- or NH4NO3-hardened molasses binder with the addition of 2.5% borax could be an alternative binder for the production of lightweight, heat-insulating materials with moderate tensile strength. When these bricks were exposed to temperatures up to 825 °C, they did not lose their strength but, rather gained strength. Therefore, molasses binder could be an alternative to cement or plaster binder for construction and building materials with specific properties. 相似文献
65.
Tamara V. Basova Irina V. Jushina Ayse G. Gürek Devrim Atilla Vefa Ahsen 《Dyes and Pigments》2009,80(1):67-72
The synthesis, liquid crystalline behavior and self-organizing properties of Cu(II)Pc bearing monoazacrown ether moieties that contain long alkyloxyphenyl N-pivotal groups are described. The Cu(II) phthalocyanine derivative has a hexagonal, columnar structure; optical absorption and vibrational spectroscopy revealed a predominantly co-facial interaction between the chromophores and their orientation parallel to a NaCl surface. It is proposed that such homeotropic alignment is attributable to the ability of the pendant monoazacrown ether groups to coordinate the Na+ ions within the NaCl surface. 相似文献
66.
67.
?mer D?nmez Fahrettin Sarcan Ayse Erol Mustafa Gunes Mehmet ?etin Arikan Janne Puustinen Mircea Guina 《Nanoscale research letters》2014,9(1):141
We report the observation of thermal annealing- and nitrogen-induced effects on electronic transport properties of as-grown and annealed n- and p-type modulation-doped Ga1 - xInxNyAs1 - y (x = 0.32, y = 0, 0.009, and 0.012) strained quantum well (QW) structures using magnetotransport measurements. Strong and well-resolved Shubnikov de Haas (SdH) oscillations are observed at magnetic fields as low as 3 T and persist to temperatures as high as 20 K, which are used to determine effective mass, 2D carrier density, and Fermi energy. The analysis of temperature dependence of SdH oscillations revealed that the electron mass enhances with increasing nitrogen content. Furthermore, even the current theory of dilute nitrides does not predict a change in hole effective mass; nitrogen dependency of hole effective mass is found and attributed to both strain- and confinement-induced effects on the valence band. Both electron and hole effective masses are changed after thermal annealing process. Although all samples were doped with the same density, the presence of nitrogen in n-type material gives rise to an enhancement in the 2D electron density compared to the 2D hole density as a result of enhanced effective mass due to the effect of nitrogen on conduction band. Our results reveal that effective mass and 2D carrier density can be tailored by nitrogen composition and thermal annealing-induced effects.
PACS
72.00.00; 72.15.Gd; 72.80.Ey 相似文献68.
The free‐radical‐initiated copolymerization of 2‐(4‐acetylphenoxy)‐2‐oxoethyl‐2‐methylacrylate (AOEMA) and 2‐(4‐benzoylphenoxy)‐2‐oxoethyl‐2‐methylacrylate (BOEMA) with 2‐[(4‐fluorophenyoxy]‐2‐oxoethyl‐2‐methylacrylate (FPEMA) were carried out in 1,4‐dioxane solution at 65°C using 2,2′‐azobisisobutyronitrile as an initiator with different monomer‐to‐monomer ratios in the feed. The monomers and copolymers were characterized by FTIR and 1H‐ and 13C‐NMR spectral studies. 1H‐NMR analysis was used to determine the molar fractions of AOEMA, BOEMA, and FPEMA in the copolymers. The reactivity ratios of the monomers were determined by the application of Fineman‐Ross and Kelen‐Tudos methods. The analysis of reactivity ratios revealed that BOEMA and AOEMA are less reactive than FPEMA, and copolymers formed are statistically in nature. The molecular weights (M w and M n) and polydispersity index of the polymers were determined using gel permeation chromatography. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with an increase in the mole fraction of FPEMA in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of FPEMA in the copolymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
69.
Although ambient processing is the key to low-cost organic solar cell production, high-vacuum thermal evaporation of LiF is often a limiting step, motivating the exploration of solution processing of LiF as an alternative electrode interlayer. Submonolayer films are realized with the assistance of polymeric micelle reactors that enable LiF particle deposition with controlled nanoscale surface coverage. Scanning Kelvin probe reveals a work function tunable with nanoparticle coverage with higher values than that of bare indium tin oxide (ITO). 相似文献
70.
Ruchan Deniz Gibbins Havva Ayse Aksoy Guldem Ustun 《International Journal of Food Science & Technology》2012,47(5):1055-1062
Aqueous enzymatic oil extraction of safflower seeds was assisted by Alcalase 2.5L and Celluclast 1.5L. Enzyme type and amount, pH, time, temperature, churning rate, dilution ratios and particle size were varied to determine their influence on the oil amount. The amount of oil recovered was higher using seeds ground to a particle size of <0.6 mm. Response surface methodology was employed for the optimisation of aqueous enzymatic oil extraction conducted with Celluclast 1.5L. When the extraction was assisted by Celluclast 1.5L, the maximum oil amount and yield were 33.3 (% w/w) and 79.7 (% w/w), respectively. The optimum conditions were 48.3 °C; 0.25 mL enzyme g?1 substance; pH, 4.84; resulting oil amount and yield were 28.2 (% w/w) 65 (% w/w), respectively. The predicted critical values were experimentally verified, and an oil amount of 27.1 (% w/w) was achieved. The enzyme treatment did not have any determining effect on the physicochemical properties of extracted oil. 相似文献