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41.
Alicia Valdez Menchaca ;Sergio Castaneda Alvarado ;Gloria Campos Posada ;Alma Domfnguez Lugo ;Alicia Silva Avila ;Samuel Hernandez Donjuan 《通讯和计算机》2014,(1):22-29
Enterprise architecture is a subject that has increased its importance in the small and medium enterprises in the manufacturing sector of the industry in Mexico. The global competitiveness of the markets has influenced the adoption of methodologies that support the strategic alignment of the processes with the goals and strategic objectives of the firms. The components of the business architecture like mission, vision, strategic objectives, products, organizational structure, business prdcesses, clients and geographic region, were collected from the firm of the case study for the design of the architecture. As a result of the practical application, an implementation model has been created and four strategic objectives were established for to improve productivity and competitiveness. This paper is a result of the architecture in a medium size manufacturing company like partial research project of analysis, design and implementing business architecture of an enterprise using ontologies for representing the core elements of the business architecture; the study presents clearly the importance of the strategic planning for the analysis and the detection of the main faults for the success of the achievement of goals and objectives. 相似文献
42.
Carlos R. Michel Narda L. López Contreras Alma H. Martínez-PreciadoAuthor vitae 《Sensors and actuators. B, Chemical》2011,160(1):271
In this work, nanostructured bismuth oxychloride (BiOCl) was prepared by a surfactant-assisted method. Bismuth trichloride and dioctyl sulfosuccinate (AOT) were dissolved in non-aqueous media, producing a fine precipitate. The calcination of the precipitated particles at 180 °C produced 3D hierarchical BiOCl semi-spherical architectures, assembled by microplates. The increase of the calcination temperature to 600 °C produced nanostructured ribbons, which are formed by the stacking of several BiOCl layers. Other microstructures can be formed at different calcination temperatures or by using other surfactants. Thick-films of the as-prepared BiOCl ribbons were made by its direct deposition on alumina substrates. The gas sensing characterization was performed at 300 and 400 °C using alternating current (AC). The tests gases were compressed air, CO, CO2 and O2. Humidity effects were discarded by using the extra dry version of these gases. At 300 °C, reproducible CO gas sensing patterns were obtained; however, the detection of CO2 and O2 produced unreliable results. At 400 °C, reliable gas sensing patterns were obtained in CO, CO2 and O2. According to its gas response, BiOCl behaved as a p-type seminconductor material. 相似文献
43.
Alma López-Avilés MCIWEM 《Water and Environment Journal》2007,21(3):217-226
Conventional methods for the estimation of flood frequency are generally based on the statistical analysis of data series resulting from the measurement of water levels at specific locations, which are translated into discharges (m3/s) using standard stage/discharge relationships. Subsequently, these gauged flows are used to identify the largest flood event experienced by a river or catchment, and to produce growth curves used in the estimation of the return periods of specific flood events, as well as in the calculation of discharges for specific required design events (e.g. return period 1 in 100 year). In areas where gauging data records are scarce, and/or the data series are short or interrupted, geomorphological interpretation of the physical environment, dating of fluvial deposits and flooding episodes and hydraulic reconstruction of past flood events can be used as complementary tools aiding conventional hydrological and flood frequency analysis methods. This paper will discuss the undertaking of this approach in the Guadalope Catchment in northeast Spain. It will examine the findings in relation to the inadequate design of existing structures such as dams, spillways, canals and reservoirs, and will also look at the potential risks associated with flooding at present. 相似文献
44.
45.
A high quality biodiesel was produced from Mexican Jatropha curcas crude oil (JCCO) by a two step catalyzed process. The free fatty acids (FFA) were first esterified with methanol, catalyzed by a solid catalyst: SiO2 pretreated with HF. The catalyst showed a high number of Lewis acid surface sites, and no CO2 or H2O adsorption activity. This catalyst showed a high FFA esterification activity and high stability. After 30 esterification runs, the catalyst activity remained unchanged. During the second step, the triglycerides present in the JCCO were transesterified with methanol catalyzed by NaOH. The chromatographic analysis of the biodiesel obtained, revealed that the process proposed in this investigation led to a very high quality biodiesel, meeting the international requirements for its utilization as a fuel. The combustion gas emissions of the JCCO biodiesel were studied by FTIR spectroscopy using a laboratory combustor. These preliminary results showed low amounts of aromatic and sulfur containing compounds. However, halogenated compounds and dicyclopentadiene were also detected at the combustor exhaust. 相似文献
46.
Protein turnover studies on a proteome scale based on metabolic isotopic labeling can provide a systematic understanding of mechanisms for regulation of protein abundances and their transient behaviors. At this time, these large-scale studies typically utilize a simple kinetic model to extract protein dynamic information. Although many high-quality, protein isotope incorporation data are available from those experiments, accurate and additionally useful protein dynamic information cannot be extracted from the experimental data by use of the simple kinetic models. In this paper, we describe a formal connection between data obtained from elemental isotope labeling experiments and the well-known compartment modeling, and we demonstrate that an appropriate application of a compartment model to turnover of proteins from mammalian tissues can indeed lead to a better fitting of the experimental data. 相似文献
47.
48.
Eugene Zakar Ronald Polcawich Madan Dubey Jeff Pulskamp Alma Wickenden John Conrad 《组合铁电体》2013,141(1):697-706
The application of a Pt/PZT/Pt sandwich structure in place of a polysilicon material for a xylophone magnetometer bar can greatly improve the sensitivity of the device. This is the first time a piezoelectric activation has been used to resonate a xylophone bar comprised of SiO2/Ta/Pt/PZT/Pt. Both optical beam and scanning laser Doppler vibrometer methods were used for characterizing the bar deflection. A fabrication process for freely suspended xylophone magnetometer bars is presented. When the device was placed in a vacuum ambient the Quality factor improved to a value of 1800. 相似文献
49.
Bradley Katherine C.; Haas Alma R.; Meisel Robert L. 《Canadian Metallurgical Quarterly》2005,119(1):224
This study examined the effects of sexual experience in female hamsters (Mesocricetus auratus) on copulatory interactions with male hamsters. Female sexual experience improved the copulatory efficiency of sexually naive males, an effect that persisted for at least 6 weeks without further sexual behavior testing. In a 2nd study, dopamine lesions made in the region of the nucleus accumbens prior to sexual experience specifically blocked the effects of the female's sexual experience on the hit rate of naive males. These results suggest that sexual experience in female hamsters increases the efficiency of copulatory interactions with males, that these effects persist in the absence of further sexual experience, and that dopamine neurotransmission in the basal forebrain underlies this effect of sexual experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Alma Antonia Pérez-Mondragón Carlos Enrique Cuevas-Suárez Nayely Trejo-Carbajal Evandro Piva Adriana Fernandes da Silva Ana María Herrera-González 《应用聚合物科学杂志》2020,137(16):48576
The objective of this work was to synthesize two bio-based monomers, using the resorcinol as raw material, and its effect as bisphenol A glycidyl dimethacrylate (Bis-GMA) eluents on different chemical–physical and biological properties of experimental photopolymerizable composite resins. The acrylic 1,3-phenylen diacrylic (1,3-FDA) and methacrylic 1,3-phenylen dimethacrylic (1,3-FDMA) monomers were synthesized and fully characterized through FTIR and 1H-NMR spectroscopies. Experimental photopolimerizable composites were formulated using Bis-GMA/1,3-FDA or Bis-GMA/1,3-FDMA as organic matrix. The materials were compared with a Bis-GMA/TEGDMA resin-based composite used as control. Polymerization kinetics was evaluated by means of FTIR spectroscopy. Polymerization stress was directly measured through a polymerization stress tester. The cell viability of the composites was evaluated using the MTT assay. One-way analysis of variance and Tukey's test were used for statistical analysis. The materials formulated with the 1,3-FDA monomer showed higher Rpmax values and lower polymerization stress values (p < 0.05), while the flexural strength, water sorption, and solubility remained similar to the TEGDMA composite. Conversely, the materials formulated with the 1,3-FDMA monomer showed a lower degree of conversion and statistically lower flexural strength (p < 0.05). All materials exhibited a cellular viability close to 100%. Concerning the study conditions, the acrylic 1,3-FDA monomer could be considered an alternative to TEGDMA in the formulation of photopolymerizable dental composite resins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48576. 相似文献