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961.
Water Resources Management - New requirements for water supply companies enforce the implementation of risk analysis and assessment methods on many levels of their operation. The approach... 相似文献
962.
This paper deals with the efficient computation of solutions of robust nonlinear model predictive control problems that are formulated using multi-stage stochastic programming via the generation of a scenario tree. Such a formulation makes it possible to consider explicitly the concept of recourse, which is inherent to any receding horizon approach, but it results in large-scale optimization problems. One possibility to solve these problems in an efficient manner is to decompose the large-scale optimization problem into several subproblems that are iteratively modified and repeatedly solved until a solution to the original problem is achieved. In this paper we review the most common methods used for such decomposition and apply them to solve robust nonlinear model predictive control problems in a distributed fashion. We also propose a novel method to reduce the number of iterations of the coordination algorithm needed for the decomposition methods to converge. The performance of the different approaches is evaluated in extensive simulation studies of two nonlinear case studies. 相似文献
963.
Modern information technologies have revolutionized agriculture in many ways. Today, positioning systems along with Internet of Things technologies enable Smart Faming with site-specific applications and interconnected machinery. Current machines and implements are equipped with multiple sensors and actors that are embedded in the machine’s Controller Area Network (CAN) using ISOBUS. In operation, such components continuously produce and exchange internal and environmental sensor information. However, CAN communication is not secure and privacy issues arise whenever different actors are involved in collaborative tasks. In this paper, we present CAN’t, a modular privacy framework for collaborative Smart Farming. The core of the framework is a special proxy that allows to apply privacy filters to selected CAN/ISOBUS data streams. Moreover, it allows to agree on the accessible level of information content for each actor. We implemented a proof-of-concept prototype based on low-cost commercial off-the-shelf hardware. Its evaluation comprises technical and privacy aspects. By using real-world ISOBUS traces as well as a commercial CAN hardware simulator, the feasibility of our approach is shown. 相似文献
964.
This paper provides an overview of the influences that different economic objectives have on the efficiencies of those optimal process designs obtained by using single- and multi-objective optimizations. Optimizations of monetary criteria, like the profit, lead to operationally and environmentally more efficient but economically less attractive designs than optimization of non-monetary economic objectives, like the internal rate of return. The net present value produces compromise designs with intermediate efficiencies and environmental impacts. These differences are significant only if the processes’ mathematical models are sufficiently accurate for establishing appropriate trade-offs between investment and cash flow. The Pareto curves obtained by different economic objectives vary regarding the maximum environmental impacts and in the intervals of the environmental indicators. The composed criteria that combine the economic and environmental indicators into one single objective produce smaller differences between optimum designs that are closer to those designs with minimum possible environmental impacts. 相似文献
965.
Controller Area Network (CAN) technology is nowadays ubiquitous in vehicular applications and is also gaining popularity in other contexts, for instance, embedded and industrial automation systems. The recent standardization of CAN with flexible data rate (CAN FD), as well as other academic proposals, have highlighted the usefulness of enhancing the CAN physical and data link layers to attain better performance and other features. This paper describes a portable software-defined CAN controller called SDCC. Besides being handy as a research tool for experimenting with novel protocol concepts at the data link layer, SDCC is also fully capable of real-time execution. Hence, it can interact with real-world CAN devices through a physical bus interface. 相似文献
966.
Francisca Holgado Gloria Márquez-Ruiz María Victoria Ruiz-Méndez Joaquín Velasco 《International Journal of Food Science & Technology》2020,55(2):833-840
The effect of oil droplet size (ODS) on the oxidative stability (OS) of dried microencapsulated oils has been scarcely studied, and results are contradictory. A few studies have shown increased OS when the ODS was reduced and this was attributed to a decrease in the surface oil content (SOC). Yet, in such studies, only the total oil fraction was evaluated. In the present work, the free (FO) and encapsulated oil (EO) fractions of freeze-dried microencapsulated sunflower oil were analysed to study the effect of changes in the ODS by using different homogenisation pressure (15 or 70 MPa) in the emulsification step. The OS of both the free and encapsulated fractions increased when the ODS was significantly reduced in two samples with different encapsulation matrix, namely caseinate/lactose and maltodextrin/sucrose/gelatine. A reduction in the SOC would explain the increased stability of the FO, but not that of the EO. An additional protective role of the interfacial film could have been involved. In conclusion, if the encapsulation matrix and the interfacial region are effective as oxygen barriers, a reduction in the ODS of the parent emulsion by an increase in the homogenisation pressure will result in capsules more stable against lipid oxidation. 相似文献
967.
Reciprocal systems based on superimposition joints, i.e. where un-notched bars sits on the top or in the bottom of each other, could be regarded as being intrinsically three-dimensional because of their natural out-of plane development. This paper presents seven of these three-dimensional configurations, conceived and built by the students of the Master of Science in “Architectural Design” at Aalborg University. They have been developed as an integral part of a 2-week workshop, organized and run by the authors during the fall semester 2011. Since physical models are instruments that trigger the exploration of new typologies because of the direct interaction they provide with the designer the students were called to deal with the issue of three-dimensionality in reciprocal systems through scale models and actual scale prototypes. 相似文献
968.
Crossmodal correspondence is of scientific and commercial interest in regard to the packaging of food and beverages. Research has shown that colors and shapes can be associated with certain aromas, but these interactions have been less extensively studied with authentic visual stimuli (i.e., packaging), or with complex food odors in a matrix. This study investigated odor-color-shape crossmodal interactions with complex odor stimuli (wine odors) and wine labels. The present research used projective mapping with 3D shapes and colors, along with a wine label matching study, to test whether chardonnay odors of different character (buttery, citrus, floral, smoky, and vegetable) were associated with certain colors and shapes. In the projective mapping experiment, most chardonnay odors were grouped similarly; however, the vegetable-forward wine was more associated with sharper shapes. In the label experiment, yellow labels tended to be better matched with all odors, except the vegetable-forward wine, which was matched equally to all colors. These findings indicate that, regardless of odor character, chardonnay is mostly associated with a yellow colored label. Interestingly, results also indicated that not all correspondences aligned with the most common color association of an odor character’s (i.e., vegetative was not strictly associated with green, nor smoky with brown, etc.). Significant correlations were found between stimuli liking and matching scores, speaking to the role of hedonics in correspondences. Overall, the present research demonstrates evidence for odor-color-shape correspondences in complex odors and realistic visual stimuli, but not as strongly as in controlled environments and simplistic stimuli. 相似文献
969.
In this study, a novel route for the modification of sunflower oil-based partial triglycerides with styrene (St) was described. For this purpose, in the first step, copolymers of St and 4-chloromethyl styrene (P(St-co-CMS)) were synthesized by free radical polymerization (FRP) and controlled/living radical polymerization (nitroxide mediated radical polymerization (NMRP)) methods. In the second step, chloro groups of these samples were transformed into azido groups by using NaN3/DMF and then azido groups were coupled with propargyl alcohol to achieve hydroxyl functional polystyrene chain (PSt-OH) via Cu(I)-catalyzed 1,3-dipolar azide-alkyne cycloaddition (CuAAC) “click” chemistry approach. Finally, alcohol groups of PSt-OH and the partial glyceride (PG) were combined by the reaction with toluene 2,4-diisocyanate (TDI). As a result, styrenated urethane oil (PG-TDI-PSt) was obtained as an oil-based binder. The structures were determined by FT-IR, 1H NMR and GPC analyses, and film properties of the products were examined according to the related standards. (PG-TDI-PSt) gave good film properties, and therefore could be considered as an applicable oil-based binder. 相似文献
970.
Synthesis of a novel zwitterionic bisphosphonate cyclopolymer containing residues of alendronic acid
The reaction of 4-(diallylammonio)butanoate, H3PO3 and PCl3 in CH3SO3H created water-insoluble 4-diallylamino-1-hydroxybutylidene-1,1-bisphosphonic acid I, a novel monomer that contained residues of the osteoporosis drug alendronic acid. Monomer (±) I, a zwitterionic tetraprotic acid, in the presence of 2 equivs. NaOH(aq) and the initiator ammonium persulfate, underwent cyclopolymerization to yield water-soluble poly(zwitterion–dianion) (± =) II. Under the influence of pH, II was equilibrated to water-soluble poly(zwitterion–trianion) (± ≡) III, polytetraanion (= =) IV, poly(zwitterion–anion) (± −) V, cationic polyelectrolyte (+) VI and water-insoluble polyzwitterion (±) VII. The solution properties of backbone charges were investigated, and protonation constants of several centers in IV were determined. Polymers that contained residues of alendronic acid should have applications in various fields, including the field of medicine. 相似文献