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61.
A method has been developed to determine the boundary conditions of gelation in the water-soluble acid polyelectrolyte-polyvalent metal salt system. In the case of sodium alginate-polyvalent metal chloride system, at chloride concentrations below 0.15mol/l, the gelation capacity increases in the series: Ca2+ <Sr2+ <Ba2+ <Cu2+ < La3+. The constants of ion exchange, resulting in the formation of intermolecular bonds, have been calculated. The gelation capacity of the sodium alginate-calcium chloride system decreases in the presence of urea and chlorides of alkali metals. 相似文献
62.
Dmitry Oshchepkov Irina Chadaeva Rimma Kozhemyakina Karina Zolotareva Bato Khandaev Ekaterina Sharypova Petr Ponomarenko Anton Bogomolov Natalya V. Klimova Svetlana Shikhevich Olga Redina Nataliya G. Kolosova Maria Nazarenko Nikolay A. Kolchanov Arcady Markel Mikhail Ponomarenko 《International journal of molecular sciences》2022,23(5)
63.
George M. Mathews Hugh Durrant-Whyte Mikhail Prokopenko 《Robotics and Autonomous Systems》2009,57(3):310-320
This paper considers the scenario where multiple autonomous agents must cooperate in making decisions to minimise a continuous and differentiable team cost function. A distributed and asynchronous optimisation algorithm is presented which allows each agent to incrementally refine their decisions while intermittently communicating with the rest of the team. A convergence analysis provides quantitative requirements on the frequency agents must communicate that is prescribed by the structure of the decision problem. In general the solution method will require every agent to communicate to and have a model of every other agent in the team. To overcome this, a specific subset of systems, called Partially Separable, is defined. These systems only require each agent to have a combined summary of the rest of the team and allows each agent to communicate locally over an acyclic communication network, greatly increasing the scalability of the system. 相似文献
64.
65.
3D computer graphics models and digitally-controlled manufacturing have come together to enable the design, visualization, simulation, and automated creation of complex 3D objects. In our work, we propose and implement a framework for designing computer graphics objects and digitally manufacturing them such that no adversary can make imitations or counterfeit copies of the physical object, even if the adversary has a large number of original copies of the object, knowledge of the original object design, and has manufacturing precision that is comparable to or superior to that of the legitimate creator of the object. Our approach is to design and embed a signature on the surface of the object which acts as a certificate of genuinity of the object. The signature is detectable by a signature-reading device, based on methods in computer graphics and computer vision, which contains some of the secret information that was used when marking the physical object. Further, the compromise of a signature-reading device by an adversary who is able to extract all its secrets, does not enable the adversary to create counterfeit objects that fool other readers, thereby still enabling reliable copy detection. We implemented a prototype of our scheme end-to-end, including the production of the physical object and the genuinity-testing device. 相似文献
66.
Youssef Travaly Mikhail Baklanov 《集成电路应用》2009,(1):37-40
随着对新化学品和集成方案了解的加深,我们不但可以减轻介电层孔隙率增加引起的负担还可以降低工艺对超低k薄膜的损伤。 相似文献
67.
Bing Dong Mikhail Gorbounov Shui Yuan Tiejun Wu Abhishek Srivastav Trevor Bailey Zheng O’Neill 《Building Simulation》2013,6(3):283-295
This paper presents an integrated energy performance modeling approach that considers heat and mass transfer through building envelope, HVAC (heating, ventilation, and air conditioning) and refrigeration systems of a retail store building with limited measured data. The internal heat gains/losses were estimated based on an Extended Kalman Filter. The simulation coupling strategy among room top units (RTUs), refrigeration display cases and zones is based on the ping-pong coupling strategy. The integrated model was validated against measured data from June to August, 2011. The results show that temperature prediction is within the ±1.5°C error band and the RTU electricity energy use prediction is within the ±10% error band. The difference between measured and simulated annual electricity consumption from the refrigeration system is 3%. Based on further analysis and diagnostics, deviations of model predictions from measured data were found to be partially due to the faults in the RTUs. Such deviation accounts for a 4% saving of the total building electrical energy consumption. 相似文献
68.
Govindan Suresh Kumar Gopalu Karunakaran Easwaradas Kreedapathy Girija Evgeny Kolesnikov Nguyen Van Minh Mikhail V. Gorshenkov Denis Kuznetsov 《Ceramics International》2018,44(10):11257-11264
We report the rapid microwave-assisted hydrothermal synthesis of mesoporous hydroxyapatite (HAp) nanocrystals with controlled size, morphology, and surface area using various organic modifiers as regulators. The products were analyzed for their crystalline nature, phase purity, morphology, particle size and pore size distribution. Results indicated that ascorbic acid, cetyltrimethyl ammonium bromide (CTAB) and polyvinylpyrrolidone (PVP) play an important role to obtain needle like, rod like and fiber like mesoporous HAp nanocrystals with different specific surface area by controlling growth habit of HAp along c-axis. In addition, the prepared samples were B-type carbonated HAp similar to bone minerals. Therefore, the present approach can be a promising way to obtain precursor for making tissue engineering scaffolds, drug/protein delivery carriers and bone fillers with tunable characteristics. 相似文献
69.
Lovász and Schrijver described a generic method of tightening the LP and SDP relaxation for any 0–1 optimization problem.
These tightened relaxations were the basis of several celebrated approximation algorithms (such as for max-cut, max-3sat, and sparsest cut). 相似文献
70.
Michael H. Butterworth Mikhail A. Semenov Andrew Barnes Dominic Moran Jonathan S. West Bruce D. L. Fitt 《Journal of the Royal Society Interface》2010,7(42):123-130
Effects of climate change on productivity of agricultural crops in relation to diseases that attack them are difficult to predict because they are complex and nonlinear. To investigate these crop–disease–climate interactions, UKCIP02 scenarios predicting UK temperature and rainfall under high- and low-CO2 emission scenarios for the 2020s and 2050s were combined with a crop-simulation model predicting yield of fungicide-treated winter oilseed rape and with a weather-based regression model predicting severity of phoma stem canker epidemics. The combination of climate scenarios and crop model predicted that climate change will increase yield of fungicide-treated oilseed rape crops in Scotland by up to 0.5 t ha−1 (15%). In contrast, in southern England the combination of climate scenarios, crop, disease and yield loss models predicted that climate change will increase yield losses from phoma stem canker epidemics to up to 50 per cent (1.5 t ha−1) and greatly decrease yield of untreated winter oilseed rape. The size of losses is predicted to be greater for winter oilseed rape cultivars that are susceptible than for those that are resistant to the phoma stem canker pathogen Leptosphaeria maculans. Such predictions illustrate the unexpected, contrasting impacts of aspects of climate change on crop–disease interactions in agricultural systems in different regions. 相似文献