We propose a new algorithm for routing packets which effectively avoids packet congestion in computer networks. The algorithm
involves chaotic neurodynamics. To realize effective packet routing, we first composed a basic method by a neural network,
which routes packets with shortest path information between two nodes in the computer network. When the computer network has
an irregular topology, the basic routing method does not work well, because most of packets cannot be transmitted to their
destinations due to packet congestion in the computer network. To avoid such an undesirable problem, we employed chaotic neurodynamics
to extend the basic method. Numerical experiments show that our proposed method exhibits good performance for scale-free networks.
We also analyze why the proposed routing method is effective, comparing the proposed method with several stochastic methods.
We introduced the method of surrogate data, a statistical hypothesis testing which is often used in the field of nonlinear
time-series analysis. Analysis of the proposed method by the method of surrogate data reveals that the chaotic neurodynamics
is most effective to decentralize the packet congestion in the computer network. 相似文献
The removal of paint on the surface of waste plastics is difficult by the conventional process; in this research, a new cleaning mechanism using atmospheric plasmas was examined through optical emission spectroscopy, electron spectroscopy for chemical analysis, and scanning electron microscopy. Results indicate that an increase of pulse frequency enables for a short processing time for the removal of the paint film, signifying that the production of radicals in plasma, especially oxygen radicals, can be controlled by pulse frequency.Plasma jets were generated under the experimental conditions of an input power of 250 W to 400 W, a pulse frequency of 2 kHz to 12 kHz, and a plasma gas flow rate of 30 L/min. Examination of the intensity ratio of the reactive species, as measured by emission spectroscopy, showed that the O/N value increased with an increase in pulse frequency. Results of analysis with electron spectroscopy for chemical analysis show that nitrogen atoms and molybdenum in only the paint film decreased through plasma processing. 相似文献
In order to elucidate the role of plasticity on interface crack initiation from a free edge and crack propagation in a nano-component,
delamination experiments were conducted by a proposed nano-cantilever bend method using a specimen consisting of ductile Cu
and brittle Si and by a modified four-point bend method. The stress fields along the Cu/Si interface at the critical loads
of crack initiation and crack propagation were analyzed by the finite element method. The results reveal that intensified
elastic stresses in the vicinity of the interface edge and the crack tip are very different, although the Cu/Si interface
is identical in both experiments. The plasticity of Cu was then estimated on the basis of the nano-cantilever deflection measured
by in situ transmission electron microscopy. The plasticity affects the stress fields; the normal stress near the interface
edge is intensified while that near the crack tip is much reduced. Both the elasto-plastic stresses are close to each other
in the region of about 10 nm. This suggests that the local interface fracture, namely, the crack initiation at the interface
edge and the crack propagation along the interface, is governed by elasto-plastic normal stress on the order of 10 nm. 相似文献
Since circulating tumor cells (CTCs) are tumor cells which are found in the blood of cancer patients, CTCs are potential tumor markers, so a rapid isolation of CTCs is desirable for clinical applications. In this paper, a three-dimensional polystyrene (PS) microfiber fabric with vacuum aspiration system was developed for capturing CTCs within a short time. Various microfiber fabrics with different diameters were prepared by the electrospinning method and optimized for contact frequency with cells. Vacuum aspiration utilizing these microfiber fabrics could filter all cells within seconds without mechanical damage. The microfiber fabric with immobilized anti-EpCAM antibodies was able to specifically capture MCF-7 cells that express EpCAM on their surfaces. The specificity of the system was confirmed by monitoring the ability to isolate MCF-7 cells from a mixture containing CCRF-CEM cells that do not express EpCAM. Furthermore, the selective capture ability of the microfiber was retained even when the microfiber was exposed to the whole blood of pigs spiked with MCF-7 cells. The specific cell capture ratio of the vacuum aspiration system utilizing microfiber fabric could be improved by increasing the thickness of the microfiber fabric through electrospinning time. 相似文献
This paper describes a new type hydrogen sulfide (H2S) gas sensor using ionic liquid (IL). In this sensor, a reservoir for the IL was integrated on a surface acoustic wave (SAW) resonator. The IL serves as an absorber for H2S gas. Mass change due to this absorption is detected as shift in the resonant frequency. In this study, we fabricated and demonstrated the sensor using the lithium niobate (LiNbO3) SAW resonator with the resonant frequency of 38 MHz. The integrated reservoir was filled by the IL 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]-[PF6]). As an experimental result, we observed the linear correlation between the frequency-shift and the exposure time of the sensor to the H2S gas. 相似文献
Using the micro-pulling-down (μ-PD) method, Tm-doped Lu3Al5O12 (Tm:LuAG) single crystals were grown to examine their scintillation properties. In transmittance spectra, they exhibited about 80% transparency in the wavelengths longer than 320 nm and five absorption lines due to Tm3+ 4f–4f transitions were observed. 241Am α-ray excited radioluminescence spectra were measured and intense 4f–4f emission peaks were observed with the host emission. When excited by 137Cs γ-Ray to obtain pulse height spectra, Tm 1% doped LuAG showed the highest light yield coupled with a photomultiplier (PMT) or a silicon avalanche photodiode (Si-APD). The light yield was estimated to be 5800 and 7300 photons/MeV for PMT and Si-APD, respectively. Decay time profiles consist of two exponential components and the fast and slow components are considered to be attributed to the host and the combination of the host and Tm3+ 4f–4f emission, respectively. 相似文献
Amorphous silicon is the most popular material in the field of semiconductors. However, little is known about its microstructures. To understand the dependence of these microstructures on the fabrication process and on structural relaxation, amorphous silicon samples fabricated by various simulated processes are classified according to structural parameters within the molecular dynamics method.
The results show that the amorphous structures fabricated by the melt-quench method have many odd-membered rings and large bond-angle deviation. The structures fabricated by the molecular-beam epitaxy method involve fewer floating bonds, smaller bond-angle deviations, and fewer six-membered rings in comparison with the melt-quenched structure. Through long-term annealing, both structures are transformed to the most stable structure as described by the Tersoff potential. It is also found that the continuous random network structure does not meet the Tersoff potential. Verification of the results through first-principle calculations shows that well-relaxed amorphous structure can be described by classical molecular dynamics despite the slightly large number of the floating bond and the overestimation of amorphous-phase energy. 相似文献
In this article, a new control scheme named repetitive control is proposed for a class of nonlinear systems described by x(t) = Ax(t) + Bu(t) + n(x(t)) and y(t) = Cx(t), in which the controlled variables follow periodic reference commands. The stability condition is derived by applying the passivity theorem. We show how to apply the repetitive control scheme to the trajectory control of a manipulator. A simple repetitive control scheme is developed for the trajectory control of a manipulator by using nonlinear compensation and feedbacks of position and velocity signals. Experimental results for a three link manipulator verify that the proposed repetitive control reduces the tracking error to a very low level. 相似文献
Transactional memory is being advanced as an alternative to traditional lock-based synchronization for concurrent programming. Transactional memory simplifies the programming model and maximizes concurrency. At the same time, transactions can suffer from interference that causes them to often abort, from heavy overheads for memory accesses, and from expressiveness limitations (e.g., for I/O operations). In this paper we propose an adaptive locking technique that dynamically observes whether a critical section would be best executed transactionally or while holding a mutex lock. The critical new elements of our approach include the adaptivity logic and cost–benefit analysis, a low-overhead implementation of statistics collection and adaptive locking in a full C compiler, and an exposition of the effects on the programming model. In experiments with both micro and macrobenchmarks we found adaptive locks to consistently match or outperform the better of the two component mechanisms (mutexes or transactions). Compared to either mechanism alone, adaptive locks often provide 3-to-10x speedups. Additionally, adaptive locks simplify the programming model by reducing the need for fine-grained locking: with adaptive locks, the programmer can specify coarse-grained locking annotations and often achieve fine-grained locking performance due to the transactional memory mechanisms. 相似文献