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1.
The usage of cling wraps is emerging as an easy and cost-effective approach to protect fresh-cut fruits and vegetables from dust, whilst improving visual appeal on retail counters. This study focused on developing an alternate, protein-based packaging material as a food grade cling wrap for food packaging applications. Zein-based cling wraps were produced, and their physical and mechanical characteristics were evaluated and compared with conventionally used chitosan biopolymer films and commercial synthetic polymer films. Antioxidant potential of the prepared films was studied, and the effectiveness of the developed films as anti-browning cling wraps was evaluated using studies conducted on fresh-cut apple slices at ambient conditions. Anti-browning effects were in par with polymeric counterparts; however, zein cling wraps could better prevent weight loss in apple slices. Zein-based films can be adopted as biodegradable food grade cling wraps as an alternative to chitosan and synthetic polymeric materials.  相似文献   
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We introduce an effective computer aided learning visual tool (CALVT) to teach graph-based applications. We present the robot motion planning problem as an example of such applications. The proposed tool can be used to simulate and/or further to implement practical systems in different areas of computer science such as graphics, computational geometry, robotics and networking. In the robot motion planning example, CALVT enables users to setup the working environment by creating obstacles and a robot of different shapes, specifying starting and goal positions, and setting other path or environment parameters from a user-friendly interface. The path planning system involves several phases. Each of these modules is complex and therefore we provide the possibility of visualizing graphically the output of each phase. Based on our experience, this tool has been an effective one in classroom teaching. It not only cuts down, significantly, on the instructor’s time and effort but also motivates senior/graduate students to pursue work in this specific area of research.  相似文献   
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This paper deals with internal challenges that the human factors/ergonomics (HFE) research faces when wishing to strengthen its contribution to development of work systems. Three established characteristics of high-quality HFE, i.e., HFE takes a systems approach, HFE is design-driven, and HFE focuses on two closely related outcomes, performance and well-being, are taken as a starting point of a methodological discussion, in which conceptual innovations, e.g. adopting the technology-in-use perspective, are proposed to support development of HFE towards the high-quality aims. The feasibility of the proposed conceptual choices is demonstrated by introducing a naturalistic HFE analysis approach including four HFE functions. The gained experience of the use of this approach in a number of complex work domains allows the conclusion that becoming design-driven appears as that most difficult quality target for HFE to reach. Creating an own design discipline identity in a multi-voiced collaboration is the key internal challenge for human factors/ergonomics.  相似文献   
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International Journal of Control, Automation and Systems - The system of multiple agents working in coordination for a given task has several advantages on faster completion, fault-tolerance, etc....  相似文献   
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This paper addresses the limits of net discourse in virtual communities. I will analyse incidents of death that shattered the 'rhetorical vision' of one particular virtual community, Xena: Warrior Palace. The observations will trace some characteristics of the community's vision of itself, how vulnerable that vision can be and how it can be maintained or revised after some unexpected occurrence shatters it. I argue that even though the rhetorical vision of virtual community can be imagined, it has to stay in touch with the 'real world' in order to have real influence on constructed online culture.  相似文献   
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The most common form of cancer for women is breast cancer. Recent advances in medical imaging technologies increase the use of digital mammograms to diagnose breast cancer. Thus, an automated computerized system with high accuracy is needed. In this study, an efficient Deep Learning Architecture (DLA) with a Support Vector Machine (SVM) is designed for breast cancer diagnosis. It combines the ideas from DLA with SVM. The state-of-the-art Visual Geometric Group (VGG) architecture with 16 layers is employed in this study as it uses the small size of 3 × 3 convolution filters that reduces system complexity. The softmax layer in VGG assumes that the training samples belong to exactly only one class, which is not valid in a real situation, such as in medical image diagnosis. To overcome this situation, SVM is employed instead of the softmax layer in VGG. Data augmentation is also employed as DLA usually requires a large number of samples. VGG model with different SVM kernels is built to classify the mammograms. Results show that the VGG-SVM model has good potential for the classification of Mammographic Image Analysis Society (MIAS) database images with an accuracy of 98.67%, sensitivity of 99.32%, and specificity of 98.34%.  相似文献   
9.
Samples of the electron-doped superconductor precursor Nd2-x-yCexLayCuO4 with 0x0.2 and y=0.5, I have been synthesized with a sol-gel method. While the as-prepared samples are in the normal state, oxygen reduction results in superconducting samples. The dependence of Tc upon Ce-doping x and oxygen content (4-) was determined in detail. It turned out that the internal pressure exerted by the La ions results in an extended superconducting range in x and compared to Nd2-xCexCuO4- Elastic neutron scattering was used to investigate the dependence of structural features upon doping. Upon oxygen reduction a non-isotropic shrinking of the unit cell (lattice parameter a increases, c decreases) and indications for interstitial oxygen were found. The local electronic surrounding of the Nd ions was observed via the crystal-field splitting by inelastic neutron scattering and turned out to be inhomogeneous. Such electronic inhomogeneities were previously measured for other high-Tc superconductors.  相似文献   
10.
In recent years the use of new technical equipment and the Internet by middle-aged people has increased. This paper presents middle-aged people’s (45 years old or older) usage of new technical equipment and analyses how their (2704 persons) symptoms are associated with the equipment. Over 70% of Finland’s middle-aged population use mobile phones daily and less than 30% use desktop computers at leisure. For example, over 80% of middle-aged people had sometimes or often experienced pain, numbness or aches in the neck and about 70% had aches in the hip and lower back. The use of new technical equipment among the group of people who are outside working life was smaller than the people’s usage in general. In the future, when new technical equipment is developed, it is important to take into account, that people (outside working life) do not use, e.g., the Internet as much as people in general. The working environment will be much more ergonomic also at home and the Internet services will be easy to use for almost everyone, even those who have little experience or knowledge of computers and the Internet.  相似文献   
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