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91.
Training has been identified as an effective tool in the development of human resources, especially in the current context of change. This work aims to analyse the realisation and demand on training courses in the Rioja wine sector in Spain. A representative sample of companies in the sector was interviewed using a questionnaire. Two types of analysis were conducted: univariate and a factorial analysis of variance. These analyses allow using a hypothesis test in which three independent variables are controlled – zone, ownership, and winery size. The results show that the realisation and demand for training are focused on topics related to wine production, and not on marketing. No significant differences were found regarding the realisation and demand for training and the independent variables. 相似文献
92.
Goyanes Manuel Demeter Márton Grané Aurea Albarrán-Lozano Irene Gil de Zúñiga Homero 《Scientometrics》2020,125(3):2299-2322
Scientometrics - With today’s research production and global dissemination, there is growing pressure to assess how academic fields foster diversity. Based on a mathematical problem/solve... 相似文献
93.
Organizations are demanding an efficacious knowledge management. Consequently, they are increasing their system innovation investments to turn information into useful knowledge for decision making obtained from heterogeneous Knowledge Sources (KSOs) such as databases, documents, and even ontologies. Methodological Resources (MRs) for the required knowledge discovering and recovering purposes have gradually become more elaborated and mature in the framework of Knowledge Engineering. Particularly, in the Ontology Learning (OL) field, there is a lack of integrated and open methodologies that could involve all the optional KSOs. In this sense, a systemic perspective is introduced combining MRs associated to diverse KSOs to improve the quality of an integral and continuous Knowledge Acquisition (KA) process. The main contributions provided by this work are on one hand, a novel Systemic Methodology for OL (SMOL) from heterogeneous KSOs which is applied for a case study and on the other hand, an evaluation of SMOL. 相似文献
94.
This paper deals with the power generation efficiency analysis of a proposed offshore wind farm topology, consisting of a SLPC (single large power converter) that simultaneously controls a group of generators. This common converter can operate at a VF (variable frequency) or at a CF (constant frequency). The results are compared with the conventional onshore wind farm scheme, where individual power converters are connected to each turbine, guaranteeing maximum power generation for the entire wind farm. A methodology to analyze different wind speed and direction scenarios, and to compute the optimal electrical frequency for each one, is presented and applied to different case studies depending on the wind farm size. In order to obtain more realistic values of wind speeds, the wake effect amongst wind turbines is considered. A wake model considering single, partial and multiple wakes inside a wind farm and taking into account different wind directions, is presented. Both wind farm topologies are analyzed by means of simulations, taking into account both wind speed variability in wind farms and the number of wind turbines. The possible resulting benefits of simplifying the MPCs (multiple power converters) of each turbine, namely saving costs, reducing losses and maintenance and increasing the reliability of the system, are analyzed, focusing on the total power extraction. The SLPC-VF scheme is also compared with a CF scheme SLPC-CF, and it is shown that a significant power increase of more than 33% can be obtained with SLPC-VF. 相似文献
95.
Paulo A.N. Dias José A.C. Alves Duncan Paul Fagg Marco S. Reis Maria H. Gil 《乙烯基与添加剂工艺杂志》2012,18(2):95-104
A new material has been developed consisting of pieces of wood embedded within a matrix of acrylic polymer, resulting in a transparent or semitransparent wood‐based product. This material presents quite appealing aesthetic features, thereby opening new possibilities for decorative applications. Because acrylic and methacrylic monomers are in the liquid state at room temperature, it is possible to introduce wood (in the current case, walnut wood) into a mixture of acrylic (hydroxypropyl acrylate) and/or methacrylic monomers (methyl methacrylate and 2‐hydroxyethyl methacrylate) along with a plasticizer (dioctyl phthalate) in the presence of a chemical initiator (benzoyl peroxide). A transparent polymeric matrix with dispersed wood is then obtained through bulk free‐radical polymerization. Introducing this reaction mixture along with pieces of wood into a mold results in a wood‐polymer composite. A 24?1 experimental fractional factorial design was implemented to study the importance of the composition of these materials on several relevant properties. The sheets produced were characterized by tensile testing, dynamic mechanical thermal analysis, thermal gravimetric analysis, and heat deflection temperature. The models obtained for predicting each property pointed to valuable insights regarding the influential constituents. In particular, our results suggested that monomers to be used in future applications of this material should be selected in terms of their cost and the desired flexibility for the final product, not in terms of their polarity. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers 相似文献
96.
Yongju Bang Joongwon LeeSeung Ju Han Jeong Gil SeoMin Hye Youn Ji Hwan SongIn Kyu Song 《International Journal of Hydrogen Energy》2012
A series of mesoporous nickel–alumina xerogel catalysts (denoted as CNAX) were prepared by a single-step carbon-templating sol–gel method using different amount of carbon template (X), and they were applied to the hydrogen production by steam reforming of liquefied natural gas (LNG). Textural properties of CNAX catalysts were improved with increasing the amount of carbon template. CNAX catalysts exhibited diffraction peaks corresponding to nickel aluminate phase, while CNA18 and CNA24 catalysts showed additional bulk nickel oxide phase. From TPR measurements, it was revealed that the interaction between nickel species and alumina in the CNAX catalysts became weakened with increasing the amount of carbon template. Crystallite size of metallic nickel in the reduced CNAX catalysts showed a volcano-shaped trend with respect to the amount of carbon template. In the steam reforming of LNG, CNAX (X = 0, 6, 12, and 18) catalysts exhibited a stable catalytic performance during the reaction, while CNA24 catalyst showed a significant catalyst deactivation. Crystallite size of metallic nickel served as an important factor determining the catalytic performance in the steam reforming of LNG. Initial LNG conversion and initial hydrogen yield increased with decreasing crystallite size of metallic nickel of the catalysts. Among the catalysts tested, CNA12 catalyst with the smallest crystallite size of metallic nickel showed the best catalytic performance. 相似文献
97.
98.
Witold Gładkowski Grzegorz Kiełbowicz Anna Chojnacka Marta Gil Tadeusz Trziszka Zbigniew Dobrzański Czesław Wawrzeńczyk 《Food chemistry》2011
The effect of feed supplementation with humic-fat preparations on the fatty acid composition of egg yolk phospholipid fractions was studied. The Lohmann Brown was the experimental hen strain and two feeding mixtures were applied – the standard feed and the mixture supplemented with humic-fat preparations. The fatty acid profile of yolk lipids was significantly affected (P = .05) by the supplementation of feed and total increase of n-3 polyunsaturated fatty acids (PUFA) was established. A different distribution of n-3 PUFA in egg yolk lipid fractions was observed: α-linolenic acid (18:3) was found in the triacylglycerol fraction, whereas docosahexaenoic acid (22:6) was detected in the phospholipid fractions. Supplementation of the hen’s diet with humic-fat preparations resulted in the production of n-3 enriched eggs with decreased n-6/n-3 ratio in all phospholipid fractions in comparison to the eggs from the control group. 相似文献
99.
We present a novel approximation of a global illumination technique called contour‐based polygonal ambient occlusion, an approach that darkens by only using a depth texture as screen‐space ambient occlusion without additional information such as a normal buffer. We introduce a discrete level structure to calculate the amount of occlusion by using the contour level, an integer value derived from the depth difference of neighboring texels. We use the uniform sampling to define the positions of the neighboring texels in the depth texture. Our method does not depend on geometric complexity because our method works in screen space and works well for both static and dynamic scenes without any precomputation. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
100.
S. M. Reshetnikov F. Z. Gil’mutdinov E. M. Borisova O. R. Bakieva 《Protection of Metals and Physical Chemistry of Surfaces》2016,52(7):1121-1127
Using the method of recording anode potentiodynamic curves in neutral and mildly alkaline borate buffer solutions, the corrosion and electrochemical behavior of iron-armco samples bombarded with oxygen ions is studied. It is shown by the method of X-ray photoelectron spectroscopy that, during such bombardment, implantation of oxygen into the surface layers of iron occurs. Therein, iron oxides of variable composition and various forms of adsorbed and absorbed oxygen are formed. These oxygen formations contribute to transfer of the iron surface to a more corrosion-resistant, passive state. 相似文献