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981.
982.
Véronique Verrez-Bagnis Marc Jér?me 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(3):230-235
Paramyosin is a muscle protein which is characteristic of all invertebrates but which is not present in vertebrate muscles. Given the functional importance of paramyosin, the purpose of this paper was to study the physico-chemical properties, including the amino acid composition and rheological behaviour, of purified paramyosin and to investigate its mode of interaction with myosin. Paramyosin was purified from the limpet (Patella caerula) by an ethanol precipitation step. It was soluble at ionic strengths below 0.05 m NaCl and its maximum solubility at neutral pH occurred at approximately 0.4 M NaCl. At this high ionic strength, the pH dependence of solubility was such that paramyosin passed quickly into solution when pH exceeded pH 5, the transitional pH value. By using an immunological method, it was shown that interactions between paramyosin and myosin occurred, even in the presence of actin. The molecular assembly of both proteins was probably specified by hydrophobic interactions, as well as by interactions enhanced by divalent cations. The changes in the dynamic shear storage modulus (G) started between 40°C and 50°C, and reached a maximum at about 75°C. 相似文献
983.
The wearable revolution is already present in society through numerous gadgets. However, the contest remains in fully deployable wearable (bio)chemical sensing. Its use is constrained by the energy consumption which is provided by miniaturized batteries, limiting the autonomy of the device. Hence, the combination of materials and engineering efforts to develop sustainable energy management is paramount in the next generation of wearable self-powered electrochemical devices (WeSPEDs). In this direction, this review highlights for the first time the incorporation of innovative energy harvesting technologies with top-notch wearable self-powered sensors and low-powered electrochemical sensors toward battery-free and self-sustainable devices for health and wellbeing management. First, current elements such as wearable designs, electrochemical sensors, energy harvesters and storage, and user interfaces that conform WeSPEDs are depicted. Importantly, the bottlenecks in the development of WeSPEDs from an analytical perspective, product side, and power needs are carefully addressed. Subsequently, energy harvesting opportunities to power wearable electrochemical sensors are discussed. Finally, key findings that will enable the next generation of wearable devices are proposed. Overall, this review aims to bring new strategies for an energy-balanced deployment of WeSPEDs for successful monitoring of (bio)chemical parameters of the body toward personalized, predictive, and importantly, preventive healthcare. 相似文献
984.
Nele Noels Marc Moeneclaey 《International Journal of Satellite Communications and Networking》2020,38(1):16-30
A new issue of the satellite telecommand synchronization and channel coding sublayer protocol includes LDPC‐coded communication link transmission units (CLTUs) that contain a 64‐bit start sequence. The novel data structures allow operation at lower signal‐to‐noise ratios than before and offer improved protection against jamming attacks. This paper considers the corresponding CLTU frame synchronization process. We derive practical algorithms to locate the start sequence in the presence of high noise levels and pulsed jamming. The different algorithms are compared in terms of implementation complexity and performance under various jamming conditions. It is shown that among the considered frame synchronizers, those involving a full search over the entire observation window provide the desired accuracy, ie, they guarantee a frame synchronization error probability that is significantly smaller than the codeword error rate, for codeword error rates near a target value of 10?4. Among these synchronizers, the full‐search hard‐decision–directed correlation‐based algorithm has the lowest complexity. 相似文献
985.
Guillaume Gouget Fabrice Mauvy U‐Chan Chung Sbastien Fourcade Mathieu Duttine Marc‐David Braida Thierry Le Mercier Alain Demourgues 《Advanced functional materials》2020,30(11)
Pure ionic conductors as solid‐state electrolytes are of high interest in electrochemical energy storage and conversion devices. They systematically involve only one ion as the charge carrier. The association of two mobile ionic species, one positively and the other negatively charged, in a specific network should strongly influence the total ion conduction. Nb5+‐ (4d0) and Ti4+‐based (3d0) derived‐perovskite frameworks containing Na+ and O2? as mobile species are investigated as mixed ion conductors by electrochemical impedance spectroscopy. The design of Na+ blocking layers via sandwiched pellet sintered by spark plasma sintering at high temperatures leads to quantified transport number of both ionic charge carriers tNa+ and tO2?. In the 350–700 °C temperature range, ionic conductivity can be tuned from major Na+ contribution (tNa+ = 88%) for NaNbO3 to pure O2? transport in NaNb0.9Ti0.1O2.95 phase. Such a Ti‐substitution is accompanied with a ≈100‐fold increase in the oxygen conductivity, approaching the best values for pure oxygen conductors in this temperature range. Besides the demonstration of tunable mixed ion conduction with quantifiable cationic and anionic contributions in a single solid‐state structure, a strategy is established from structural analysis to develop other architectures with improved mixed ionic conductivity. 相似文献
986.
Oriol Marc Martínez-Fernández Silverio Behutiye Woubshet Farré Carles Kozik Rafał Seppänen Pertti Vollmer Anna Maria Rodríguez Pilar Franch Xavier Aaramaa Sanja Abhervé Antonin Choraś Michał Partanen Jari 《Software Quality Journal》2020,28(3):931-963
Software Quality Journal - Quality requirements (QRs) are a key artifact needed to ensure the quality and success of a software system. Despite their importance, QRs rarely get the same degree of... 相似文献
987.
Many applications in geometry processing require the computation of local parameterizations on a surface mesh at interactive rates. A popular approach is to compute local exponential maps, i.e. parameterizations that preserve distance and angle to the origin of the map. We extend the computation of geodesic distance by heat diffusion to also determine angular information for the geodesic curves. This approach has two important benefits compared to fast approximate as well as exact forward tracing of the distance function: First, it allows generating smoother maps, avoiding discontinuities. Second, exploiting the factorization of the global Laplace–Beltrami operator of the mesh and using recent localized solution techniques, the computation is more efficient even compared to fast approximate solutions based on Dijkstra's algorithm. 相似文献
988.
Christoph Hannebauer Marc Hesenius Volker Gruhn 《Empirical Software Engineering》2018,23(5):2795-2828
Program comprehension is an important skill for programmers – extending and debugging existing source code is part of the daily routine. Syntax highlighting is one of the most common tools used to support developers in understanding algorithms. However, most research in this area originates from a time when programmers used a completely different tool chain. We examined the influence of syntax highlighting on novices’ ability to comprehend source code. Additional analyses cover the influence of task type and programming experience on the code comprehension ability itself and its relation to syntax highlighting. We conducted a controlled experiment with 390 undergraduate students in an introductory Java programming course. We measured the correctness with which they solved small coding tasks. Each test subject received some tasks with syntax highlighting and some without. The data provided no evidence that syntax highlighting improves novices’ ability to comprehend source code. There are very few similar experiments and it is unclear as of yet which factors impact the effectiveness of syntax highlighting. One major limitation may be the types of tasks chosen for this experiment. The results suggest that syntax highlighting squanders a feedback channel from the IDE to the programmer that can be used more effectively. 相似文献
989.
Pantelic Vera Postma Steven Lawford Mark Jaskolka Monika Mackenzie Bennett Korobkine Alexandre Bender Marc Ong Jeff Marks Gordon Wassyng Alan 《International Journal on Software Tools for Technology Transfer (STTT)》2018,20(1):95-117
International Journal on Software Tools for Technology Transfer - Although widely used in embedded systems design, Matlab/Simulink is not considered a state-of-the-art design environment by the... 相似文献
990.
Xiaopeng Zhang Guanbo Bao Weiliang Meng Marc Jaeger Hongjun Li Oliver Deussen Baoquan Chen 《Computer Graphics Forum》2017,36(8):402-417
We present a level of detail (LOD) method designed for tree branches. It can be combined with methods for processing tree foliage to facilitate navigation through large virtual forests. Starting from a skeletal representation of a tree, we fit polygon meshes of various densities to the skeleton while the mesh density is adjusted according to the required visual fidelity. For distant models, these branch meshes are gradually replaced with semi‐transparent lines until the tree recedes to a few lines. Construction of these complete LOD models is guided by error metrics to ensure smooth transitions between adjacent LOD models. We then present an instancing technique for discrete LOD branch models, consisting of polygon meshes plus semi‐transparent lines. Line models with different transparencies are instanced on the GPU by merging multiple tree samples into a single model. Our technique reduces the number of draw calls in GPU and increases rendering performance. Our experiments demonstrate that large‐scale forest scenes can be rendered with excellent detail and shadows in real time. 相似文献