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121.
Some of the problems associated with assessing the retrofit effectiveness of apartment buildings in urban areas are considered. The retrofit of houses should be followed by the amelioration of their surroundings. The priority order of districts to be renovated depends on the condition of the buildings in a district and on strategic urban development programmes. In order to determine the profitability of investments in housing retrofit, a number of retrofit scenarios should be developed. The authors of this paper offer a new approach to determining the retrofit effectiveness of houses based both on expected energy savings and the increase in market value of renovated buildings. In line with the proposed approach, retrofit scenarios for apartment buildings in Vilnius were developed, i.e. retrofit investment packages for various districts were prepared and arranged in the priority order for their application according to the method of geographical analysis suggested by the authors. 相似文献
122.
Arturas Katelnikovas Jonas Jurkevi?ius Karolis KazlauskasPranciškus Vitta Thomas JüstelAivaras Kareiva Artūras ?ukauskasGintautas Tamulaitis 《Journal of Alloys and Compounds》2011,509(21):6247-6251
Efficiency of sol-gel derived Y3−xAl5O12:Cex3+ (YAG:Ce) and Y3−xMg2AlSi2O12:Cex3+ (YMASG:Ce) phosphors, which are prospective for application in white light emitting diodes (LED), is studied. Sets of samples containing different cerium amount x from 0.015 to 0.06 and sintered at different temperatures (1400-1550 °C) were investigated. Importance of absorption peculiarities in agglomerates of phosphor nanocrystals is demonstrated by studying the excitation wavelength dependence of quantum efficiency and by applying PL measurements in confocal mode. Emission saturation is demonstrated to occur at higher excitation intensities than those typical for operating white LEDs. 相似文献
123.
David Delgado-Gómez David Aguado Jorge Lopez-Castroman Carlos Santacruz Antonio Artés-Rodriguez 《Expert systems with applications》2011,38(5):5129-5132
In this article, an expert system based on support vector machines is developed to predict the sale performance of some insurance company candidates. The system predicts the performance of these candidates based on some scores, which are measurements of cognitive characteristics, personality, selling skills and biodata. An experiment is conducted to compare the accuracy of the proposed system with respect to previously reported systems which use discriminant functions or decision trees. Results show that the proposed system is able to improve the accuracy of a baseline linear discriminant based system by more than 10% and that also exceeds the state of the art systems by almost 5%. The proposed approach can help to reduce considerably the direct and indirect expenses of the companies. 相似文献
124.
Adrian Ieta Hunter Gerlach Thomas E. Doyle Art Pallone Robert Amundson 《Particulate Science and Technology》2013,31(3):238-244
There has been a lot of research on liquid atomization by means of electrospray, particularly because of its many practical applications. Nevertheless, full understanding and control of the electrospray mechanisms are still incomplete. An experimental setup was developed in order to investigate the frequency characteristics of droplet formation and ejection at the tip of Taylor's cone of aqueous electrosprays. Droplet formation and oscillations were monitored using a Kodak Ektapro high-speed camera. The frequency of droplet formation at the tip of the capillary needle was analyzed. Droplet frequency formation appears to exhibit three distinct regimes with an abrupt transition from one regime to another. Droplet formation was recorded at different needle-plate electrode distances. Based on the analysis of experimental data a scaling law for droplet formation was found. 相似文献
125.
Single protein junctions consisting of azurin bridged between a gold substrate and the probe of an electrochemical tunneling microscope (ECSTM) have been obtained by two independent methods that allowed statistical analysis over a large number of measured junctions. Conductance measurements yield (7.3 ± 1.5) × 10(-6)G(0) in agreement with reported estimates using other techniques. Redox gating of the protein with an on/off ratio of 20 was demonstrated and constitutes a proof-of-principle of a single redox protein field-effect transistor. 相似文献
126.
Ginés B. Martínez-Hernández Francisco Artés-Hernández Franciane Colares-Souza Perla A. Gómez Presentación García-Gómez Francisco Artés 《Food and Bioprocess Technology》2013,6(8):2135-2149
The microbial, physical, sensory and nutritional quality of boiled (vacuum and conventional), steamed, pressure cooked, sous vide, microwaved (sous vide and conventional), deep-fried (vacuum and conventional) and grilled kailan-hybrid broccoli (Bimi®) after cooking was studied. Sous vide microwaving greatly decreased microbial counts, achieving very low psychrophilic and enterobacteria counts (1.1 and 0.2 log CFU g?1, respectively). Vacuum boiling and sous vide reduced the stem broccoli firmness by approximately 54–58 %, reaching a pleasant and moderate softening. Sous vide, grilling and steaming induced the lowest stem colour changes. Generally, all cooking treatments showed a good overall sensory quality. The total phenolic content (1,148 mg CAE kg?1 fw) usually increased after cooking, with microwave and grilled treatments registering the highest increases up to 2-fold. Commonly, the total antioxidant capacity (296.6 mg AAE kg?1 fw) increased after cooking by sous vide, microwaving and frying treatments registering the highest increments, by approximately 3.6-fold. Generally, the cooking process reduced the initial vitamin C content, with vacuum and conventional boiling showing the lowest and highest losses with 27 and 62 %, respectively, while vacuum deep frying preserved the initial value (1,737 mg kg?1 fw). As a main conclusion, the studied grilling and vacuum-based cooking treatments resulted in better microbial quality, colour, stem firmness and sensory quality than the remaining ones. This maintained or even improved the total antioxidant content of the new kailan-hybrid broccoli studied. 相似文献
127.
AE Benamou T Art DJ Marlin CA Roberts P Lekeux 《Canadian Metallurgical Quarterly》1998,11(2-3):231-235
Recurrent airway obstruction (RAO) is an asthma-like condition of the horse that represents a major cause of morbidity and loss of performance. The exact pathogenesis of asthma in man is unclear but the role of endothelin (ET) is currently under investigation, thus sparking interest in the bronchoconstrictive and vasoconstrictive properties of endothelin in the equine-specific disease entity. In this study, we investigated the levels of ET-1 in systemic blood, as well as in bronchoalveolar lavage (BAL) from horses with RAO. We also studied how these values might correlate with those of lung function tests and pulmonary artery pressure. Five horses with RAO were evaluated both in remission and in crisis and compared to five control horses. RAO horses had significantly (P<0.05) higher systemic ET-1 levels than control horses. They also had a negative arteriovenous ET-1 difference that may correspond to a net uptake of ET-1 in the lung. RAO horses in crisis had increased amounts of immunoreactive ET in BAL fluid compared to normal control subjects. Additionally, the reduction in lung function seen in RAO horses in crisis was significantly correlated with lower epithelial lining fluid ET-1 levels. Our results demonstrate that endothelin may contribute to the pathogenesis of asthma. 相似文献
128.
B Artén 《Canadian Metallurgical Quarterly》1998,95(28-29):3161-3162
129.
F Rollin H Amory D Desmecht A Linden T Art F Lomba P Lekeux 《Canadian Metallurgical Quarterly》1997,44(2):79-90
In the genus Eulemur (Malagasy lemurs) karyotype diversification has occurred mainly through Robertsonian mechanisms of chromosome fusion (Rumpler et al., 1976). Eulemur coronatus is the sole species to have the largest genome size, due to a very large amount of C-heterochromatin, mostly located at the pericentromeric regions of the largest chromosomes (Warter and Rumpler, 1985). This increase in C-heterochromatin was thought to be due to DNA amplification (Ronchetti et al., 1993). The aim of this work was to investigate whether the large C-heterochromatin of Eulemur coronatus might have derived by amplification of the smaller C-heterochromatin of Eulemur macaco, a closely related species with smaller genome size. To obtain information on the overall base composition of the total genomes, on the relative interspersion of AT and GC base paris along the DNA molecule and on the structural differences in C-heterochromatin, we used a quantitative cyto-chemical approach, based on fluorescence resonance energy transfer (FRET) between DNA-specific fluorochromes (i.e. the AT-specific Hoechst 33258, and the non base-specific dye, propidium iodide). Micro-spectrofluorometry and image analysis were used to investigate both the overall FRET efficiency and its spatial distribution along the chromosome arms. FRET efficiency values of the DNA in C-heterochromatin were significantly different in the two Eulemur species, indicating a different qualitative composition of repetitive DNA. This suggests that the repetitive DNA of Eulemur coronatus cannot have originated by amplification in toto of the repetitive DNA sequences of Eulemur macaco. 相似文献
130.
Navia-Vázquez A. Pérez-Cruz F. Artés-Rodríguez A. Figueiras-Vidal A.R. 《Journal of Signal Processing Systems》2004,37(2-3):223-235
Many learning algorithms have been used for data mining applications, including Support Vector Classifiers (SVC), which have shown improved capabilities with respect to other approaches, since they provide a natural mechanism for implementing Structural Risk Minimization (SRM), obtaining machines with good generalization properties. SVC leads to the optimal hyperplane (maximal margin) criterion for separable datasets but, in the nonseparable case, the SVC minimizes the L 1 norm of the training errors plus a regularizing term, to control the machine complexity. The L 1 norm is chosen because it allows to solve the minimization with a Quadratic Programming (QP) scheme, as in the separable case. But the L 1 norm is not truly an “error counting” term as the Empirical Risk Minimization (ERM) inductive principle indicates, leading therefore to a biased solution. This effect is specially severe in low complexity machines, such as linear classifiers or machines with few nodes (neurons, kernels, basis functions). Since one of the main goals in data mining is that of explanation, these reduced architectures are of great interest because they represent the origins of other techniques such as input selection or rule extraction. Training SVMs as accurately as possible in these situations (i.e., without this bias) is, therefore, an interesting goal. We propose here an unbiased implementation of SVC by introducing a more appropriate “error counting” term. This way, the number of classification errors is truly minimized, while the maximal margin solution is obtained in the separable case. QP can no longer be used for solving the new minimization problem, and we apply instead an iterated Weighted Least Squares (WLS) procedure. This modification in the cost function of the Support Vector Machine to solve ERM was not possible up to date given the Quadratic or Linear Programming techniques commonly used, but it is now possible using the iterated WLS formulation. Computer experiments show that the proposed method is superior to the classical approach in the sense that it truly solves the ERM problem. 相似文献