This paper investigates passivity-based pose control via an obstacle avoidance navigation function for three-dimensional (3-D) eye-in-hand visual feedback systems. Firstly, visual motion observer-based pose control fo...
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Metabolomic analysis can indeed enhance the prime variable dataset for the monitoring of perfusion cultures by providing a higher resolution view of the metabolic state. Metabolic profiles can capture physiological st...
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Metabolomic analysis can indeed enhance the prime variable dataset for the monitoring of perfusion cultures by providing a higher resolution view of the metabolic state. Metabolic profiles can capture physiological state shifts over the course of the perfusion cultures and indicate a metabolic “signature” of the phase transitions, which is not observable from prime variable data. Notably, metabolomics provides orthogonal (to prime variables) evidence that all cultures follow this same metabolic state shift with cell age, independently of bioreactor scale. Additionally, this analysis can increase the information content of process development experiments by helping better understand the impact of changes in bioreactor operating conditions on cell physiology. In this context, metabolic profiling could be integrated into the monitoring of cell physiology in perfusion cultures.
A Pyrex nanochannel device was fabricated using AFM nanolithography in conjunction with MEMS-based microfabrication. The fabrication process began with the patterning of microchannels on a Pyrex substrate using photol...
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Artificial bee colony (ABC) is an optimization algorithm inspired on the intelligent behavior of honey bee swarms. It is suitable to be applied when mathematical techniques are impractical or provide suboptimal soluti...
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Chitin is widely distributed in nature, being the main structural component of the exoskeleton of crustaceans and is non-toxic, biodegradable and biocompatible. These exoskeletons once discarded become an industrial w...
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Chitin is widely distributed in nature, being the main structural component of the exoskeleton of crustaceans and is non-toxic, biodegradable and biocompatible. These exoskeletons once discarded become an industrial waste creating environmental pollutant. In order to find an alternative use, the present work exploits the extraction of the chitosan from chitin that is present in the exoskeletons of shrimps Litopenaeus vannamei and crabs Ucides cordatus and transforms it into high valued products, which can help solving the environmental problem as well to provide extra income to the fishermen. One example is the manufacture of nanomembranes from chitosan for the application in medical textiles. Nanomembranes using electrospinning of chitosan solutions (7% and 5wt%) with 100:0 v/v (TFA/DCM) and 70:30 v/v (TFA/DCM) were produced. Morphological properties of chitin and chitosan were studied using SEM, DRX, and thermal properties through TG/DTG and molecular structure by FTIR analysis. TG/DTG showed thermal decomposition of chitosan samples. X-ray diffraction analysis indicated the semi-crystalline structure of chitosan, and highly crystalline structure for chitin. Morphologies of the nanomembranes were also observed from scanning electron micrographs. Results showed that the nanomembranes with 5% chitosan solutions with 70:30 v/v (TFA/DCM) showed facilitation in the formation of the nanomembranes. The nanomembranes of shrimp and crab with 5% 70:30 v/v (TFA/DCM) had higher breaking tension and breaking extension. With positive results obtained, the present work will help the authorities to organize the fishermen to have consciousness in the collection of exoskeleton waste as well as helping to have a better environment.
Differential Evolution (DE) is a simple and efficient stochastic global optimization algorithm of evolutionary computation field, which involves the evolution of a population of solutions using operators such as mutat...
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Characterization and optimization of material properties during synthesis and processing are frequent problems in materials science and engineering. In the present paper, the use of design of experiments (DOE) to char...
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This paper deals with imperfect preventive maintenance (PM) for a serial production system. PM is carried out periodically at a fixed interval. PM can not restore the machines as new, but between as-good-as-new and as...
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This paper deals with imperfect preventive maintenance (PM) for a serial production system. PM is carried out periodically at a fixed interval. PM can not restore the machines as new, but between as-good-as-new and as-bad-as-old (imperfect). PM decreases virtual age of the machines which may different for one machine to another. The failure occurred between PM is repaired minimally. The optimal coordinated PM interval is obtained to meet the availability target at minimum cost. The coordinated PM results are compared with those of independent PM. Numerical examples are given to illustrate the model solution.
We analyze the geometric structure and mechanical stability of a complete set of isostatic and hyperstatic sphere packings obtained via exact enumeration. The number of nonisomorphic isostatic packings grows exponenti...
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We analyze the geometric structure and mechanical stability of a complete set of isostatic and hyperstatic sphere packings obtained via exact enumeration. The number of nonisomorphic isostatic packings grows exponentially with the number of spheres N, and their diversity of structure and symmetry increases with increasing N and decreases with increasing hyperstaticity H≡Nc−NISO, where Nc is the number of pair contacts and NISO=3N−6. Maximally contacting packings are in general neither the densest nor the most symmetric. Analyses of local structure show that the fraction f of nuclei with order compatible with the bulk (rhcp) crystal decreases sharply with increasing N due to a high propensity for stacking faults, five- and near-fivefold symmetric structures, and other motifs that preclude rhcp order. While f increases with increasing H, a significant fraction of hyperstatic nuclei for N as small as 11 retain non-rhcp structure. Classical theories of nucleation that consider only spherical nuclei, or only nuclei with the same ordering as the bulk crystal, cannot capture such effects. Our results provide an explanation for the failure of classical nucleation theory for hard-sphere systems of N≲10 particles; we argue that in this size regime, it is essential to consider nuclei of unconstrained geometry. Our results are also applicable to understanding kinetic arrest and jamming in systems that interact via hard-core-like repulsive and short-ranged attractive interactions.
An atmospheric pressure plasma system has been developed to prepare zinc oxide (ZnO) thin film on the silicon substrate. The precursor of dry powder of Zinc acetylacetonate hydrate was directly sublimated as vapor and...
An atmospheric pressure plasma system has been developed to prepare zinc oxide (ZnO) thin film on the silicon substrate. The precursor of dry powder of Zinc acetylacetonate hydrate was directly sublimated as vapor and carried by Argon into the downstream of Nitrogen plasma jet. The films deposition process was carried out at low temperature and the substrate temperature was not over 300 oC. The examinations of thin film sample by X-ray diffraction (XRD) showed the major peak at 34o was the hexagonal wurtzite structure of ZnO. The surface morphologies and thickness of the films were evaluated by scanning electron microscopy (SEM). The mean square surface roughness of the ZnO film was only 4.063 nm and a smooth surface of ZnO thin film was obtained.
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