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351.
A group of machines for processing a set of jobs in a manufacturing system is often located in a serial line. An efficient strategy for locating these machines such that the total travel distance or the cost of transporting the jobs is minimized is desired. In this research, the assumption of a linear line with equally spaced machine location is relaxed. This research addressed problems of locating unique machines. It is found that the machine distances possess unique properties in this type of a problem. Utilizing these properties, heuristic strategies are proposed to obtain efficient solution where optimal methods are expected to be computationally prohibitive. A lower bound for the optimum solution is also proposed. Results are encouraging. 相似文献
352.
R. Carroll 《Theoretical and Mathematical Physics》2007,152(1):904-914
Quantization using quantum potentials is described in terms of momentum fluctuations, and it is related to Fisher information
and entropy.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 1, pp. 32–44, July, 2007. 相似文献
353.
We introduce the concept of C0-systems, which can be used to represent syntactic objects of graph-based formal systems with inheritance.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 4, pp. 159–170, 2004. 相似文献
354.
355.
S.N. Vdovichev B.A. Gribkov S.A. Gusev E. Il’ichev Yu.N. Nozdrin G.L. Pakhomov A.V. Samokhvalov R. Stolz A.A. Fraerman 《Journal of magnetism and magnetic materials》2006
The effect of an array of ferromagnetic nanoparticles on the field-dependent critical current of the short overlap Josephson junction is experimentally studied. Large reversible variations of the maximum critical current are observed depending on the magnetic state of the particles. The pronounced commensurability effects are detected which are proved by the additional peaks of magnetic field induced diffraction pattern. 相似文献
356.
A. Bartnik H. Fiedorowicz R. Jarocki L. Juha J. Kostecki R. Rakowski M. Szczurek 《Applied physics. B, Lasers and optics》2006,82(4):529-532
The first results of experiments on direct photo-etching of heated PTFE using a 10 Hz X-ray source based on a laser-irradiated gas puff target are presented. X-ray radiation in the wavelength range from 6 to 20 nm was produced as a result of irradiation of a double-stream gas puff target with Nd:YAG laser pulses of energy 0.8 J and time duration 3 ns. The resulting X-ray pulses with energy of about 100–200 mJ were used to irradiate samples of PTFE to create microstructures by direct photo-etching. Strong enhancement of the photo-etching process was observed for samples heated up to 300 °C. PACS 52.38.Ph; 81.65.Cf; 61.82.Pv 相似文献
357.
M. R. Bedilov R. M. Bedilov A. R. Matnazarov M. M. Sabitov Zh. O. Kamalova 《Physics of the Solid State》2006,48(9):1629-1633
The effect of accumulation on the formation of multiply charged ions in optically opaque solids as a function of the number and the angle of incidence of laser pulses is investigated by mass spectrometry. It is revealed that the accumulation effect manifests itself at prethreshold power densities q = 108–109 W/cm2 irrespective of the angle of incidence of laser radiation α = 18°–85° and at subthreshold power densities q > 1010 W/cm2 in the case of grazing incidence of laser radiation at an angle α = 85°. The accumulation effect brings about an increase in the maximum charge multiplicity Z max of tungsten ions and a decrease in the number of impurity ions and in their intensity. No accumulation effect is observed at subthreshold power densities when laser radiation is incident at an angle α = 18°. 相似文献
358.
The impedance spectra of Pb5Ge3O11 single crystals are measured in the frequency range from 5 Hz to 13 MHz at temperatures of 600 to 800 K in dry air and in
a dry or wet nitrogen gas. It is found that the temperature and the gas composition significantly affect the electrical properties
of the compound. The data obtained are used to discuss the origin of crystal lattice defects and their influence on charge
transfer. It is concluded that the conduction is mixed in character (p-type electronic and ionic due to oxygen ions). The proton conduction is shown experimentally to be feasible. The possible
mechanisms of proton transport in Pb5Ge3O11 are discussed. 相似文献
359.
R. Knizikevi?ius 《Applied Surface Science》2006,253(3):1581-1583
The ion-beam-assisted etching of silicon in Cl2 environment is considered. The theoretically calculated dependences of silicon etching rate on the flux of Cl2 molecules at different ion current densities are compared with experimentally measured. The composition of the adsorbed layer is determined. It is found that SiCl2 molecules prevail in the adsorbed layer. The reciprocal of relative concentration of SiCl2 molecules in the adsorbed layer linearly depends on the ion-to-neutral flux ratio. 相似文献
360.
Highly ordered composite nanowires with multilayer Ni/Cu and NiFe/Cu have been fabricated by pulsed electrodeposition into
nanoporous alumina membrane. The diameter of wires can be easily varied by pore size of alumina, ranging from 30 to 100 nm.
The applied potential and the duration of each potential square pulse determine the thickness of the metal layers. The nanowires
have been characterized by transmission electron microscopy (TEM), magnetic force microscopy (MFM), and vibrating sample magnetometer
(VSM) measurements. The MFM images indicate that every ferromagnetic layer separated by Cu layer was present as single isolated
domain-like magnet. This technique has potential use in the measurement and application of magnetic nanodevices. 相似文献