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61.
This study investigated the influence of monthly variation on the composition and properties of raw farm milk collected as part of a full-scale cheese-making trial in a region in northern Sweden. In our companion paper, the contribution of on-farm factors to the variation in milk quality attributes is described. In total, 42 dairy farms were recruited for the study, and farm milk samples were collected monthly over 1 yr and characterized for quality attributes of importance for cheese making. Principal component analysis suggested that milk samples collected during the outdoor period (June–September) were different from milk samples collected during the indoor period. Despite the interaction with the milking system, the results showed that fat and protein concentrations were lower in milk collected during May through August, and lactose concentration was higher in milk collected during April through July than for the other months. Concentrations of free fatty acids were generally low, with the highest value (0.86 mmol/100 g of fat) observed in February and the lowest (0.70 mmol/100 g of fat) observed in June. Plasmin and plasminogen-derived activities varied with sampling month without a clear seasonal pattern. The pH of farm tank milk ranged from 6.60 to 6.82, with the lowest and highest values in September and February, respectively. The highest somatic cell count was observed in August (201 × 103 cells/mL) and the lowest in April (143 × 103 cells/mL). The highest value of gel strength, was recorded in December (88 Pa) and the lowest in July (64 Pa). Rennet coagulation time and gel strength were inversely correlated, with the lowest rennet coagulation time value observed in December. Orthogonal projections to latent structures (OPLS) and discriminant analysis adaptation of OPLS identified casein micelle size and total proteolysis as the milk quality attributes with major responses to sampling month, with smaller casein micelle size and higher total proteolysis associated with the outdoor months. Using discriminant analysis adaptation of OPLS to further investigate causes behind the variation in milk traits revealed that there were factors in addition to feeding on pasture that differed between outdoor and indoor months. Because fresh grass was seldom the primary feed in the region during the outdoor period, grazing was not considered the sole reason for the observed difference between outdoor and indoor periods in raw milk quality attributes.  相似文献   
62.
Remarkable technical progress in the area of structural biology has paved the way to study previously inaccessible targets. For example, large protein complexes can now be easily investigated by cryo-electron microscopy, and modern high-field NMR magnets have challenged the limits of high-resolution characterization of proteins in solution. However, the structural and dynamic characteristics of certain proteins with important functions still cannot be probed by conventional methods. These proteins in question contain low-complexity regions (LCRs), compositionally biased sequences where only a limited number of amino acids is repeated multiple times, which hamper their characterization. This Concept article describes a site-specific isotopic labeling (SSIL) strategy, which combines nonsense suppression and cell-free protein synthesis to overcome these limitations. An overview on how poly-glutamine tracts were made amenable to high-resolution structural studies is used to illustrate the usefulness of SSIL. Furthermore, we discuss the potential of this methodology to give further insights into the roles of LCRs in human pathologies and liquid–liquid phase separation, as well as the challenges that must be addressed in the future for the popularization of SSIL.  相似文献   
63.
The assembly of colloidal semiconductive nanocrystals into highly ordered superlattices predicts novel structure-related properties by design. However, those structure–property relationships, such as charge transport depending on the structure or even directions of the superlattice, have remained unrevealed so far. Here, electric transport measurements and X-ray nanodiffraction are performed on self-assembled lead sulfide nanocrystal superlattices to investigate direction-dependent charge carrier transport in microscopic domains of these materials. By angular X-ray cross-correlation analysis, the structure and orientation of individual superlattices is determined, which are directly correlated with the electronic properties of the same microdomains. By that, strong evidence for the effect of superlattice crystallinity on the electric conductivity is found. Further, anisotropic charge transport in highly ordered monocrystalline domains is revealed, which is attributed to the dominant effect of shortest interparticle distance. This implies that transport anisotropy should be a general feature of weakly coupled nanocrystal superlattices.  相似文献   
64.
Process oriented industrial classification based on energy intensity   总被引:1,自引:0,他引:1  
The Standard Industrial Classification (SIC) code has been used in the United States to categorize manufactured products. This classification is useful for many commercial and business related applications. However, when checked against energy use data collected through the Industrial Assessment Center (IAC) of San Diego State University (SDSU), the energy use profile of the SIC groups showed objectionable deviations within each group, rendering the code less than useful for overall energy based grouping and analyses. In this paper, a Process Oriented Energy Intensity Classification (POEIC) is introduced. When examined with data from about 270 plants of the IAC, this new classification offered more coherent and consistent energy use profile with smaller standard deviation for the selected energy intensity parameters than that of the SIC code.  相似文献   
65.
66.
ABSTRACT

ICT4D research is faced with the challenge of rapidly changing technologies and increasingly complex social dynamics and development processes. We argue that ICT4D research requires a more acute sense of where our research is situated within a broader picture of development, e.g. with a better understanding of development processes, their ideological nature, the power structures and driving forces, and the mechanisms through which ICTs may be embedded in and shape these processes. Such a reflexivity is crucial not least in justifying our claims of contribution, but also in understanding the implications and potential impact of our research and practice. This editorial seeks to explore key conceptual components in ICT4D and their relationships, including dimensions of development, perspectives of development, conceptions of artefacts, and theory of change. A tentative conceptual schema is presented that connects these conceptual components.  相似文献   
67.
In many industries, the frequency of production ramp-ups has increased due to shorter product life cycles and increased product variety. Production often takes place at globally dispersed facilities for customers in multiple markets, for example, in the automotive industry. Therefore, ramp-up planning must be carried out for a network. The planning problem at hand is to simultaneously optimise the allocation of products of a common product platform to plants, the timing of ramp-ups and ramp-downs, ramp-up duration and shape of capacity and production and transportation volumes with respect to the net present value of the profit. We develop a hierarchical planning framework and place strategic ramp-up planning therein. We provide a mixed integer programming model for this planning problem. Following the example of a German car manufacturer in the premium segment, we conduct a numerical analysis to obtain insights into optimal ramp-up and ramp-down decisions. The results show that it could be beneficial to use both steep and flat ramp-up curves. The impact of flexibility in the choice of ramp-up slots and the number of ramp-up curves provided on the objective value is substantial. The strategic ramp-up planning model outperforms sequential planning approaches.  相似文献   
68.
Packaging and the role it plays in supply chain efficiency are overlooked in most design and development research. An opportunity exists to meet the needs of supply chains to increase efficiency. This research presents three propositions on how to reduce the gap between supply chain needs and satisfaction in interaction with the product and packaging system. It also proposes a supply chain focused packaging design and development method to better satisfy supply chain needs placed on packaging. An extensive literature review was conducted, and a Tetra Pak derived case study was developed. The propositions were formulated and became the basis for improving Tetra Pak's existing packaging design and development method by better integrating supply chain needs. This was accomplished by using an expanded operational life cycle perspective that includes the entire supply chain. The resulting supply chain focused packaging design, and development method enables improved supply chain efficiency while considering the product, the processes and cost. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
69.
Packaging has great potential to contribute to sustainable development through its functions. Previous research has indicated a need for increased knowledge among consumers, suppliers, authorities and media of how packaging functions and features influence sustainable development. Previous research also shows the need for a common terminology of packaging functions and features in order to facilitate and improve communication and understanding in development and decision processes. This conceptual paper sets out to identify, collect, analyse and systemize packaging functions and features and evaluate them based on their indirect contributions to sustainable development. The systemized functions and features are expressed in generic terminology. Three clusters of packaging functions were identified from the literature: protect, facilitate handling and communicate. Nineteen packaging features were also identified. They were grouped under the three functions and elaborated based on their indirect contributions to the environmental, social and economic dimensions of sustainable development. Fourteen potential positive indirect effects were identified including decreased product waste, reduced risk for human health hazards, increased handling and transport efficiency. Decreased product waste was generated by 13 of the features and was thus the most frequently appearing. Reducing waste is thereby indicated to be a manifold matter, but also one of great potential. The proposed terminology can contribute to an increased understanding of how packaging can actually contribute to sustainable development. In a theoretical context, this paper attempts to complement earlier work in sustainable packaging development by its emphasis on the indirect contributions of packaging to sustainable development.  相似文献   
70.
Omnidirectional mobile robots offer interesting features for industrial and service applications, in particular, when operating in tight spaces. Compared to car-like nonholonomic vehicles, they provide a higher degree of maneuverability, and often require less complex path planning and control schemes. Three different types of holonomic wheels that enable omnidirectional motion have been proposed in literature: universal, Mecanum, and ball wheel mechanisms. A problem commonly associated with the first two wheel types is that they induce vibrations in the system due to the discontinuous contact points. In this article, a ball wheel mechanism with superior features including slip measurement, free-wheel modus and attrition sensing is presented. The first prototype was built using additive manufacturing. The requirements for the design and possible improvements for future versions are discussed. Based on the presented ball wheel drive, a design for an omnidirectional mobile robot platform driven by three redundant ball wheel units is proposed. The velocity kinematic model of this mobile base is also addressed. Moreover, motion planning for an individual ball drive is demonstrated by means of an online trajectory generation scheme. The pseudocode of the trajectory planning algorithm implemented in LabVIEW is then presented. Finally, the motion characteristics of the ball drive mechanism are tested and its functionality is evaluated in detail. Measurements obtained from these tests show that the slip between the ball wheel and the ground can be estimated quite accurately. Hence, it is expected that these improved dead-reckoning estimates will result in a higher positioning accuracy of the final base.  相似文献   
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