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21.
The environmental impacts of packages have been found to be relatively small compared with the food items they contain. Furthermore, from the environmental and operational point of view, the most significant task of the package is to protect the product, which is important to acknowledge in the packaging design process. This study introduces a guiding framework for designing sustainable food packaging. In this approach, the entire life cycle of the product–package combination is taken into consideration. The emphasis is on the prevention of food losses in packaging design as a major environmental criterion. Consideration of the properties of both the package and the product itself when designing the final package will lead to a better end result with smaller product losses and environmental impacts. By using different assessment methods in the different stages of the packaging design, the sustainability of the package can be enhanced. The decision making of the packaging designer is facilitated with methods that are introduced step by step and in a certain order that will also allow for corrective measures through back‐loops in the design process. The purpose is to integrate sustainability aspects at all stages firmly into the design process. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
22.
Since the third wave in human–computer interaction (HCI), research on user experience (UX) has gained momentum within the HCI community. The focus has shifted from systematic usability requirements and measures towards guidance on designing for experiences. This is a big change, since design has traditionally not played a large role in HCI research. Yet, the literature addressing this shift in focus is very limited. We believe that the field of UX research can learn from a field where design and experiential aspects have always been important: design research. In this article, we discuss why design is needed in UX research and how research that includes design as a part of research can support and advance UX design practice. We do this by investigating types of design-inclusive UX research and by learning from real-life cases of UX-related design research. We report the results of an interview study with 41 researchers in three academic research units where design research meets UX research. Based on our interview findings, and building on existing literature, we describe the different roles design can play in research projects. We also report how design research results can inform designing for experience methodologically or by providing new knowledge on UX. The results are presented in a structured palette that can help UX researchers reflect and focus more on design in their research projects, thereby tackling experience design challenges in their own research.  相似文献   
23.
Transesterification of phospholipids in different reaction conditions   总被引:3,自引:0,他引:3  
Transesterification of synthetic dimyristoyl phosphatidylcholine with oleic acid by commercial lipase preparations fromAspergillus niger andRhizomucor miehei was studied in the presence and absence of solvent. A high-performance liquid chromatography method for determination of the modified phosphatidylcholine was developed. Under solvent-free conditions, transesterification could be carried out as efficiently as in toluene, and the degree of hydrolysis was lower than in toluene. Transesterification was influenced by the water content as well as by the fatty acid concentration in the reaction mixture. The optimum water content for transesterification in solvent-free reaction medium was higher than in toluene with both lipases. The yield of modified phosphatidylcholine increased, and the degree of hydrolysis decreased with increasing fatty acid concentration. The maximum yield of modified phospha-tidylcholine, 35% of the original phospholipid, was obtained withR. miehei lipase.  相似文献   
24.
Chemical modification of cotton to improve fibre dyeability   总被引:6,自引:0,他引:6  
A new fibre-reactive quaternary compound containing an acrylamide residue was synthesised and used as a cotton modification reagent. The agent was applied to cotton fabrics using a pad-bake process. It was found that the treated fibre could be dyed with reactive dyes without the addition of salt or alkali. The reactive dyes were almost completely exhausted and showed a high degree of covalent bonding with the pretreated cellulose. The effect of varying the pretreatment conditions was investigated and the optimum conditions for pretreating and dyeing were established.  相似文献   
25.
A new bi-objective genetic programming (BioGP) technique has been developed for meta-modeling and applied in a chromatographic separation process using a simulated moving bed (SMB) process. The BioGP technique initially minimizes training error through a single objective optimization procedure and then a trade-off between complexity and accuracy is worked out through a genetic algorithm based bi-objective optimization strategy. A benefit of the BioGP approach is that an expert user or a decision maker (DM) can flexibly select the mathematical operations involved to construct a meta-model of desired complexity or accuracy. It is also designed to combat bloat – a perennial problem in genetic programming along with over fitting and under fitting problems. In this study the meta-models constructed for SMB reactors were compared with those obtained from an evolutionary neural network (EvoNN) developed earlier and also with a polynomial regression model. Both BioGP and EvoNN were compared for subsequent constrained bi-objective optimization studies for the SMB reactor involving four objectives. The results were also compared with the previous work in the literature. The BioGP technique produced acceptable results and is now ready for data-driven modeling and optimization studies at large.  相似文献   
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27.
Computationally expensive multiobjective optimization problems arise, e.g. in many engineering applications, where several conflicting objectives are to be optimized simultaneously while satisfying constraints. In many cases, the lack of explicit mathematical formulas of the objectives and constraints may necessitate conducting computationally expensive and time-consuming experiments and/or simulations. As another challenge, these problems may have either convex or nonconvex or even disconnected Pareto frontier consisting of Pareto optimal solutions. Because of the existence of many such solutions, typically, a decision maker is required to select the most preferred one. In order to deal with the high computational cost, surrogate-based methods are commonly used in the literature. This paper surveys surrogate-based methods proposed in the literature, where the methods are independent of the underlying optimization algorithm and mitigate the computational burden to capture different types of Pareto frontiers. The methods considered are classified, discussed and then compared. These methods are divided into two frameworks: the sequential and the adaptive frameworks. Based on the comparison, we recommend the adaptive framework to tackle the aforementioned challenges.  相似文献   
28.
The effects of three plasticizers and two plasticizer concentrations on the topography and soiling of poly (vinyl chloride) (PVC) were studied. Palmitic acid and triolein were chosen to represent solid and liquid soils. The feasibility of using infrared spectroscopy to quantify the amount of soil on PVC was examined. The structure of the solid model soil on plasticized PVC was studied with optical microscopy and atomic force microscopy. Palmitic acid formed two different structures on the PVC surface. Both the type and concentration of the plasticizer influenced the structure of the oily soil on plasticized PVC. The wetting of plasticized PVC with the liquid oily soil was compared to wetting with water through the measurement of the contact angles. Plasticized PVC was hydrophobic and oleophilic. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
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30.
Potato starch was oxidized by hydrogen peroxide in alkaline and acidic reaction conditions with copper, iron and tungstate catalysts in order to introduce carboxyl and carbonyl groups to the starch molecule. Carbonyl contents up to 6.6 per 100 glucose units could be obtained, whereas carboxyl content remained low (up to 1.4). Starch yields in the alkaline and acidic reactions were 90 and 99%, respectively. The molecular weight decreased markedly with the degree of oxidation, and was dependent on the catalyst used. Rheological measurements revealed that when the molecular weight of the moderately oxidized starch was high, a very firm gel (G' = 40kPa) was obtained with 25% starch concentration. When the degree of oxidation increased, the storage modulus G' decreased. The more the oxidized starch contained carbonyl groups, the higher was the gelatinization temperature.  相似文献   
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