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991.
992.
Silvia Gillermina Ceballos-Maga?a Jose Marcos Jurado Roberto Mu?iz-Valencia Angela Alcázar Fernado de Pablos María Jesus Martín 《Food Analytical Methods》2012,5(2):260-265
The elemental profile of tequila samples from the three main production areas of the State of Jalisco, namely Amatitlan, Guadalajara,
and Tequila, was used to carry out their geographical characterization. With this aim, the concentration of Al, Ba, Ca, Cu,
Fe, K, Mg, Mn, Na, S, Sr, and Zn was determined by inductively coupled plasma atomic emission spectroscopy. Principal component
analysis was addressed to visualize data trends. The number of input variables was reduced by means of backward stepwise linear
discriminant analysis and support vector machines were used to construct an adequate classification model. The best classification
performance was obtained by a linear support vector machine model with 100% of prediction ability. 相似文献
993.
Pampean region agroecosystems are devoted to agricultural and farming activities, but in the crop field matrix there are relicts of remnant natural habitats. Poultry farms mainly harbour commensal species as house mice and rats, which are rarely present in surrounding habitats. We assessed if neighbourhood to poultry farms affect the presence of Mus musculus in crop fields and their borders, and if rodent community in poultry farms is influenced by the species present in surrounding crop fields and borders. We found that habitat had a significant effect on the abundance of M. musculus. This species showed higher abundance in poultry farms than in crop field borders. Calomys laucha was the unique native species that was captured in farm sheds. We found higher abundance of native species in crop field borders than in crop fields independent of the proximity to the poultry farms. We conclude that rodent communities in poultry farms are little influenced by the surroundings, and show a dominance of M. musculus independently of the presence of native rodent species in neighbour habitats. On the other hand, farms do not export M. musculus to surrounding habitats, and borders only function as corridors for dispersal among farms, while crop fields are rarely used. 相似文献
994.
What Business Owners Expect From a Crisis Manager? A Competency Model: Survey Results From Czech Businesses 下载免费PDF全文
This competency model of a crisis manager has been developed based on cooperation with managers and experts in the field of crisis management. The brainwriting method was used to generate an overview of the competencies expected of a crisis manager. Using a mind map three basic groups of competencies were developed. The participants used Saaty's method to determine the significance of individual competencies. The different attributes of individual competencies according to the level of their development were established. Finally all individual competencies were assigned a target value which indicates the expected level of competence for the position of a crisis manager. The model of competencies is a practical tool for the establishment of crisis management system in a company. 相似文献
995.
María-José De la Haba Dolores Pérez-Marín Diego Rial-Huerta María-Teresa Sánchez 《Food Analytical Methods》2014,7(3):606-615
Texture-related parameters were assessed in intact green asparagus at harvest and during postharvest storage using near-infrared spectroscopy combined with MPLS and LOCAL algorithms. Three spectrophotometers were evaluated for this purpose: a monochromator (range, 400–2,500 nm), a diode-array Vis–NIR spectrophotometer (range, 400–1,700 nm), and a handheld micro-electro-mechanical system (MEMS) spectrophotometer (range, 1,600–2,400 nm). Three hundred green asparagus spears (cv. “Grande”) were used to obtain calibration models based on reference data and NIR data. Results for maximum shear force showed that LOCAL algorithm improved the predictive capacity of models constructed using all three NIRS instruments, increasing r 2 by 24, 16, and 56 % and reducing the SEP(c) values by 11, 8, and 14 %, respectively. For cutting energy, the LOCAL also improved the predictive capacity of the models (r 2 increased by 3 % for the monochromator and the diode-array instrument and by 6 % for the MEMS device; and the SEP(c) decreased by 3 % in the three instruments). It is worth noting that while the monochromator and diode-array instruments displayed similar predictive capacity for the parameters tested, the MEMS instrument achieved slightly poorer results but has clear advantages for the measurement of texture in intact asparagus, being economical, portable, and easy to use in situ. 相似文献
996.
José L. Rodríguez Rosanna M. Minardi Erica P. Schulz Olga Pieroni Pablo C. Schulz 《Journal of surfactants and detergents》2012,15(2):147-155
The composition of the mixed micelles formed by benzethonium chloride and dodecyl trimethyl ammonium bromide in water were
experimentally determined by a combination of surfactant ion-selective electrodes and UV–Vis spectroscopy measurements. Results
were compared with the computed compositions from three theories on mixed micelles available in the literature (Regular Solution,
Motomura’ and Georgiev’s). The basis of the Junquera and Aicart method and the determination of the micelle aggregation number
(N) by pyrene fluorescence quenching, i.e., the constancy of N and the mixed micelle composition when the total concentration is changed, were not supported by our experimental results. Experimental micelle compositions were statistically equal to those computed
by Regular Solution Theory. The mixed micelle composition and the quantity of non-micellized surfactant molecules change with
concentration above the critical micelle concentration, and therefore do not support the assumptions used in the Junquera
and Aicart procedure and in the determination of N by pyrene fluorescence quenching. The reason why the latter procedure gives N values similar to those obtained from other techniques is discussed. 相似文献
997.
Fernando Valdés Roberto Iglesias Felipe Espinosa Miguel A. Rodríguez 《Applied Intelligence》2012,37(2):267-279
This paper describes an innovative routing strategy for intelligent transportation units willing to perform merging manoeuvres with a moving convoy. In particular, we consider a transportation unit located inside a city (pursuer unit), and which wishes to join a convoy that is constantly moving around the city. We first describe a solution that considers idealistic conditions, i.e., the traveling time along each street is constant. We then go on to improve our first approach to deal with the realistic random nature of the traveling times experienced by the pursuer and by the convoy leader. Our search strategy applies Dynamic Programming to achieve a meeting point that is optimal in two ways: on one hand, the optimal destination is the one closest to the current pursuer??s position; on the other hand, the optimal meeting point must minimize the time that elapses until the pursuer meets the convoy (considering that the pursuer must always arrive first). Calculating the optimal path to every possible destination is highly inefficient, error prone and time consuming. On the contrary, we propose an efficient search strategy that will achieve the meeting point and the path to it, both optimally and in a very short time. This enables the real-time application of our approach either for finding new solutions or for re-planning old ones owing to unexpected real-conditions. 相似文献
998.
The study explored the feasibility of using Web keyword analysis as an alternative to link analysis and tested the feasibility in a multi-industry environment. The keyword is the organization??s name, in this case the company name. American companies from five industries were included in the study. The study found that the Web visibility of a company as measured by the number of Webpages on which the company name appears correlates with the company??s business measures (revenue, profits, and assets). The correlation coefficients are similar to that between the inlink counts and the business measures. This suggests that the keyword count (searched by the company name) could replace inlink count as an alternative indicator of some commonly used business measures. The co-word (the co-occurrence of the names of two companies on Webpages) count was used as a measure of the relatedness of the two companies. Multidimensional scaling (MDS) analysis was applied to the co-word matrices and generated MDS maps that showed relationships among companies in a multi-industry context. Keyword data were collected from three different types of Websites (general Websites, blog sites, and Web news sites) and results were compared. The study found blog sites to be the better source to collect data for this type of study. The comparison of MDS maps generated from co-link data and the blog co-word data showed that the co-word analysis is as effective as co-link analysis in mapping business relationships. The value of the study is not limited to the business sector as the co-word method could be applied to analysing relationships among other types of organizations. 相似文献
999.
Characterization of a water-based paint for corrosion protection 总被引:1,自引:0,他引:1
Paula Dias Catarina Carneiro Luísa Andrade José Sousa João Machado Adélio Mendes 《Journal of Coatings Technology and Research》2012,9(3):365-374
Corrosion of steel rebars in reinforced concrete is one of the major problems in the construction industry. Carbonation reactions
of concrete with carbon dioxide and, mainly, the chloride salts action are the main causes responsible for concrete degradation.
Protective coatings help to improve the durability of concrete structures by acting as a physical barrier against the corrosion
agents. Waterborne paints are usually used for concrete protection rather than solvent-based paints since they are less pollutant.
The aim of this work is to investigate the influence of the pore size and porosity on the permeability of the paints films
toward sodium chloride. Three characterization methods from membrane science were implemented to characterize paint coatings.
The time-lag method was used to determine the permeability toward the sodium chloride and toward helium and argon, these for
approximately 100% relative humidity. From the seven waterborne paints formulated, only one was found to be suitable for surface
protection of reinforced concrete, since its permeability toward NaCl was smaller than 10−14 m2 s−1, the threshold value required by National Laboratory of Civil Engineering (LNEC) in Portugal. For the formulated paints,
it was observed that the average pore size correlates well with the permeability toward sodium chloride. This is an important
result since obtaining the permeability toward sodium chloride of corrosion protective paints is very time consuming, while
the average pore size can be obtained in a much shorter time. 相似文献
1000.
José Juan Carbajal-Hernández Luis P. Sánchez-Fernández Jesús A. Carrasco-Ochoa José Fco Martínez-Trinidad 《Expert systems with applications》2012,39(12):10571-10582
The continuous monitoring of physical, chemical and biological parameters in shrimp culture is an important activity for detecting potential crisis that can be harmful for the organisms. Water quality can be assessed through toxicological tests evaluated directly from water quality parameters involved in the ecosystem; these tests provide an indicator about the water quality. The aim of this study is to develop a fuzzy inference system based on a reasoning process, which involves aquaculture criteria established by official organizations and researchers for assessing water quality by analyzing the main factors that affect a shrimp ecosystem. We propose to organize the water quality parameters in groups according to their importance; these groups are defined as daily, weekly and by request monitoring. Additionally, we introduce an analytic hierarchy process to define priorities for more critical water quality parameters and groups. The proposed system analyzes the most important parameters in shrimp culture, detects potential negative situations and provides a new water quality index (WQI), which describes the general status of the water quality as excellent, good, regular and poor. The Canadian water quality and other well-known hydrological indices are used to compare the water quality parameters of the shrimp water farm. Results show that WQI index has a better performance than other indices giving a more accurate assessment because the proposed fuzzy inference system integrates all environmental behaviors giving as result a complete score. This fuzzy inference system emerges as an appropriated tool for assessing site performance, providing assistance to improve production through contingency actions in polluted ponds. 相似文献