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991.
Fredrik Wikberg Thomas Olofsson Anders Ekholm 《Construction Management & Economics》2013,31(1-2):196-207
There are two main routes for customers of industrialized house building to follow: either rigid platforms offering preconfigured products, often called ‘type houses’, or more flexible platforms open to customization. The problem in customization is to link customer requirements with system opportunities. In axiomatic design processes, this problem is understood as the transformation of customer requirements in the architectural view into design parameters that are supported by the system. A new method is proposed that allows requirements and constraints of an industrialized building platform to be handled fully in the architectural view through configuration with so-called architectural objects. It is based upon established theories and complies with the rationale of separating platform development from product customization. An experimental study, using standard building information modelling software, shows that a hierarchical structure of architectural objects can support both the development, as well as the configuration process, of the platform. Modularization in the architectural view is believed to be an important first step to capturing user requirements in the development of platforms for a specific market segment. It is also anticipated that if these requirements can be conceptualized as architectural objects the capabilities in different configurator solutions can be made more transparent to the customer. 相似文献
992.
Sandra Pousette Martin Löfgren Birgitta Nilsson Anders Gustafsson 《Packaging Technology and Science》2014,27(9):727-738
There are several reasons why people find it troublesome to use and handle consumer packages. The European Committee for Standardization recently suggested a technical specification (TS) regarding packaging and ease of opening. The present study has expanded the procedure by including consumer satisfaction measurements in two steps and engaging panels comprising two separate age groups. The expanded method, which used six different packages as test objects, engaged 75 panellists, 40 in the older group (65–80 years) and 35 in the younger group (25–40 years). The expanded method not only included the same operations as described in the TS but also included panellists who graded each handling element separately on a ‘smiley’ scale, along with feedback for their grades and an overall judgement of the package handling. The grading feedback differed between the two groups. The younger panellists mainly noted issues that were not connected to openability, while older panellists noted openability as the most influential factor. Further analysis revealed that openability was also a key issue for the younger panellists, despite their claims to the contrary. Satisfaction was the most critical TS element for describing a package as being easy to open. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
993.
Carbazole‐Based Hole‐Transport Materials for Efficient Solid‐State Dye‐Sensitized Solar Cells and Perovskite Solar Cells 下载免费PDF全文
994.
Jessica Bolinsson Martin Ek Johanna Trägårdh Kilian Mergenthaler Daniel Jacobsson Mats-Erik Pistol Lars Samuelson Anders Gustafsson 《Nano Research》2014,7(4):1-18
In this report we explore the structural and optical properties of GaAs/A1GaAs heterostructure nanowires grown by metalorganic vapour phase epitaxy using gold seed-particles. The optical studies were done by low-temperature cathodo- luminescence (CL) in a scanning electron microscope (SEM). We perform a systematic investigation of how the nanowire growth-temperature affects the total photon emission, and variations in the emission energy and intensity along the length of the nanowires. The morphology and crystal structures of the nanowires were investigated using SEM and transmission electron microscopy (TEM). In order to correlate specific photon emission characteristics with variations in the nanowire crystal structure directly, TEM and spatially resolved CL measurements were performed on the same individual nanowires. We found that the main emission energy was located at around 1.48 eV, and that the emission intensity was greatly enhanced when increasing the GaAs nanowire core growth temperature. The data strongly suggests that this emission energy is related to rotational twins in the GaAs nanowire core. Our measurements also show that radial overgrowth by GaAs on the GaAs nanowire core can have a deteriorating effect on the optical quality of the nanowires. Finally, we conclude that an in situ pre-growth annealing step at a sufficiently high temperature significantly improves the optical quality of the nanowires. 相似文献
995.
Johan Isaksson Anders Åsblad Thore Berntsson 《Clean Technologies and Environmental Policy》2014,16(7):1393-1402
In this paper, the influence on the system performance and greenhouse gas (GHG) emissions of different biomass pretreatment methods before gasification and Fischer–Tropsch (FT) crude production was evaluated. Entrained flow gasification has the benefit of producing a practically tar-free synthesis gas with nearly complete carbon conversion. This gasifier type requires a relatively dry fuel, with small particle size, at high pressure. The size can be acquired by milling, which is energy intensive and feeding is challenging. Torrefaction of biomass facilitates milling; it thus requires less electricity, however, the torrefaction process requires heat. Pyrolysis decomposes the biomass into gaseous, liquid, and solid parts, respectively. This further makes feeding easier, but comes with a greater heat demand than torrefaction. The impact of the different pretreatment methods on the overall energy system has been evaluated using process integration methodology. The results show that the excess heat from an FT process with a biomass input of 300 MWHHV can replace the bark boiler in a large chemical pulp and paper mill, producing 350,000 tonnes of bleached paperboard annually. With the preconditions given for this study, thermal pretreatment of biomass may be beneficial in terms of wood-to-FT crude efficiency, with efficiencies up to 68 %, assuming 40 % electrical efficiency. Pretreatment using pyrolysis performed the best in regards to GHG emissions, if CO2 from acid gas removal was vented, while milling, with an annual reduction of around 700,000 tonnes of CO2,eq, had the best results if the CO2 was captured and sequestrated. 相似文献
996.
Frode Eika Sandnes Tek Beng Tan Anders Johansen Edvin Sulic Eirik Vesterhus Eirik Rud Iversen 《Universal Access in the Information Society》2012,11(4):421-431
Touch-based interaction is becoming increasingly popular and is commonly used as the main interaction paradigm for self-service kiosks in public spaces. Touch-based interaction is known to be visually intensive, and current non-haptic touch-display technologies are often criticized as excluding blind users. This study set out to demonstrate that touch-based kiosks can be designed to include blind users without compromising the user experience for non-blind users. Most touch-based kiosks are based on absolute positioned virtual buttons which are difficult to locate without any tactile, audible or visual cues. However, simple stroke gestures rely on relative movements and the user does not need to hit a target at a specific location on the display. In this study, a touch-based train ticket sales kiosk based on simple stroke gestures was developed and tested on a panel of blind and visually impaired users, a panel of blindfolded non-visually impaired users and a control group of non-visually impaired users. The tests demonstrate that all the participants managed to discover, learn and use the touch-based self-service terminal and complete a ticket purchasing task. The majority of the participants completed the task in less than 4?min on the first attempt. 相似文献
997.
The influence of two diets with different fatty acid compositions has been studied with regard to overall pork quality and significance of specific fatty acids on sensory attributes in fried chops and oven roasts. Twenty castrates and 20 females were in a balanced experimental set-up fed with a standard diet supplemented with α-tocopherol (200mg/kg feed) where the fat source was either 3% of palm oil or 3% rapeseed oil. After slaughter, despite differences in lipid composition and sensory attributes, no significant difference in overall meat quality parameters and flavour precursors was found. Comparison of the two diets showed that supplementation with rapeseed oil resulted in a significantly higher content of C18:3n-3 (polar lipid (PL), neutral lipid (NL)), C18:2n-6c (NL) and C20:2 (NL) in LD and C18:1n-9c, C18:2n-6c, C18:3n-3, C20:3n-3, C22:5n-3 in backfat, while supplementation with palm oil resulted in a higher content of C16:0 (NL), C16:1 (PL), C18:1n-9t (NL) in LD and C16:0, C17:0, C18:0, C16:1, C20:4n-6 in backfat. A positive and significant correlation between the contents of C18:2n-6c, C20:3n-6 in the PL fraction and the sensory attributes fried meat odour and sweet odour were found in fried pork chops from female pigs. Likewise, positive correlations were seen between the content of C18:1n-9c in the PL fraction and sensory attributes such as sourish odour, piggy odour and piggy flavour in whole oven roasts. These data substantiate the view that specific fatty acids in the PL fraction influences flavour attributes in pork. 相似文献
998.
999.
Matthias Bues Achim Pross Oliver Stefani Silvia Frey Doreen Anders Jakub Späti Anna Wirz‐Justice Ralph Mager Christian Cajochen 《Journal of the Society for Information Display》2012,20(5):266-272
Abstract— In commodity LC flat‐panel displays, the traditional CCFL backlight is being replaced more and more by LEDs. The typical spectrum of LED‐lit displays shows a significantly higher amount of blue light in the range around 464 nm. Blue light in this wavelength area suppresses the melatonin level in humans and thus effects the biological clock. Our hypothesis was that the amount of blue light reaching the human eye from a LED‐backlit display is sufficient to have a significant effect on the biological clock. The results of clinical user studies comparing the effects of LED‐ vs. CCFL‐backlit displays on humans, resulting from the emitted amount of 464‐nm light, will be presented. It was found that the LED‐backlit display causes significant suppression of melatonin, which effects the biological clock of the test persons, indicating the necessity for displays with a controllable 464‐nm emission. A technical concept for a display with such functionality will be presented. 相似文献
1000.
XML graphs have shown to be a simple and effective formalism for representing sets of XML documents in program analysis. It has evolved through a six year period with variants tailored for a range of applications. We present a unified definition, outline the key properties including validation of XML graphs against different XML schema languages, and provide a software package that enables others to make use of these ideas. We also survey the use of XML graphs for program analysis with four very different languages: Xact (XML in Java), Java Servlets (Web application programming), XSugar (transformations between XML and non-XML data), and XSLT (stylesheets for transforming XML documents). 相似文献