In this paper, we investigate the stability of patterns embedded as the associative memory distributed on the complex-valued Hopfield neural network, in which the neuron states are encoded by the phase values on a unit circle of complex plane. As learning schemes for embedding patterns onto the network, projection rule and iterative learning rule are formally expanded to the complex-valued case. The retrieval of patterns embedded by iterative learning rule is demonstrated and the stability for embedded patterns is quantitatively investigated.
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
We study a partial differential equation modeling the self-motion of camphor particles atop a water surface. The model equation is presented in the form of a reaction-diffusion system where source terms are expressed by delta functions. The resulting system is a point mass model for diffusing particles, where the role of the delta functions is to express camphor source locations. In our model, point sources interact with each other and move by the gradient of the concentration field. We will discuss analytical properties of the model equation. In particular, we will study properties of traveling pulse solutions, whose existence are reduced to the solution of an ordinary differential equation, coupled with a boundary value problem. The existence and stability of solutions will be shown and we will compare our findings with those which have utilized characteristic function source terms.
PL
W pracy przedstawiono różniczkowe równania cząstkowe opisujące ruch własny cząstek kamfory na powierzchni wody. Równania modelu zaprezentowano w formie systemu reakcji- dyfuzji, w którym człon źródła jest wyrażony jako funkcje delta. Otrzymany system jest modelem punktowej masy dyfuzji cząstek, w którym rolą funkcji delta jest określenie położenia źródeł kamfory. W opracowanym modelu punktowe źródła działają wzajemnie na siebie i poruszają się zgodnie z gradientem pola stężenia. W publikacji omówiono analityczne własności opracowanych równań. Szczególny nacisk położono na badania własności rozwiązania w postaci ruchomego pulsu, którego istnienie ograniczono do rozwiązania zwyczajnych równań różniczkowych sprzężonych z problemem brzegowym. Wykazano istnienie i stabilność rozwiązania. Wyniki badań zostaną porównane z analogicznymi rozwiązaniami wykorzystującymi funkcje charakterystyczne dla członów źródłowych.
3
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
In this paper the influences of atmospheric gas such as oxygen or argon upon seizure are investigated. The hydrostatic journal bearings are used as a test apparatus. Oxygen and argon were used as a lubricant in bearing test process. Bronze bearings finished by lapping are used under the combination with steel shafts finished by honing. It was clarified that the process of gas makes an important role for frictional force, origin of debris and the seizure. On the other hand, plastic deformation of the asperities of surface roughness by rubbing action seemed to be a main reason for seizure of similar materials of steel. The surface finishing influences upon the origin of debris and the seizure superior to atmospheric gas.
4
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
We proposed a new type hydrostatic journal bearing with a floating bush to decrease the frictional torque. The characteristics of proposed bearing are calculated and we found out the optimum design parameter. Moreover, we fabricated the test bearing and measured the characteristics of bearing. The calculated results and the measured results are relatively coincide with each other.
5
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Influences of the surface finishes upon seizure are investigated experimentally by using hydro-static air bearings as an experimental apparatus. Bronze and steel bearings finished by lapping and turning are used under the combination with steel shafts finished by honing. It was clarified that bronze bearings finished by lapping came to seizure more easily than the one finished by turning and the wear debris played an important role in this case. On the other hand, plastic deformation of the asperities of surface roughness by rubbing action seemed to be a main reason for seizure of similar materials of steel.
This paper presents a hydrodynamic lubrication theory for journal bearings lubricated with ferro-fluid. A two-dimensional lubrication equation considering the magnetic force, the angular momentum of particle and the change of the apparent viscosity depend on the magnetic fields is proposed. According to this equation, the characteristics of the finite length journal bearings lubricated with ferro-fluid are investigated.
The thermal decomposition of BaTiO(C₂O₄)₂ 4H₂O and formation of BaTiO₃ were investigated by thermogravimetric analysis (TGA), differential thermal analysis combined with mass-spectroscopy (DTA-MS), high-temperature X-ray diffraction (XRD), and in situ scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TGA and DTA-MS showed that the dehydration occurred in a temperature range of 25 ÷ 240°C, followed by the decomposition of BaTiO(C₂O₄)₂ 4H₂O to BaCO₃, TiO₂, CO and CO₂ in a range of 240 ÷ 470°C. A porous structure showing the escape of CO and CO₂ gases was observed in an SEM image of a specimen at 400°C. Only diffuse peaks appeared in XRD charts in 200 ÷ 500°C, indicating that the BaCO₃ and TiO₂ are amorphous and/or micro-crystalline. XRD also disclosed that hexagonal BaTiO3 crystallites were formed by the solid-state reaction of the BaCO₃ and TiO₂ in range of 500 ÷ 650°C and then transformed to cubic crystals above 650°C. The direct formation of cubic BaTiO₃ crystals also occurred as a retareded reaction of the BaCO₃ and TiO₂ above 730°C.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.