This study is concerned with problems of ultrafast and high heat flux heat transfer with phase change. We employ the cubic interpolated propagation (CIP) method coupled with a thermoconvective model to examine the history of large-scale phase change, that is, melting and evaporation, and the mechanisms of heat transfer as a wave. It is found that wave-type heat transfer as a shock wave with phase change can be simulated without a hyperbolic heat conduction equation by means of the CIP method. Melting and evaporation occur in the energy deposition region, and energy is transferred by a shock wave beyond an energy penetration depth. The propagation velocity is hardly damped outside the energy deposition region inside aluminum thin foil, but the peak value in density, pressure, and temperature is damped rapidly. For one of the dissipation process mechanisms, generation of thermal stress can be considered. Further, it is found that the initial velocity of shock wave generated inside the energy deposition region is different for each initial incident laser intensities, though the propagation velocity is constant beyond the energy penetration depth in spite of an initial incident laser intensity. 相似文献
In this paper, we propose a new video conferencing system that presents correct gaze directions of a remote user by switching among images obtained from multiple cameras embedded in a screen according to a local user’s position. Our proposed method reproduces a situation like that in which the remote user is in the same space as the local user. The position of the remote user to be displayed on the screen is determined so that the positional relationship between the users is reproduced. The system selects one of the embedded cameras whose viewing direction towards the remote user is the closest to the local user’s viewing direction to the remote user’s image on the screen. As a result of quantitative evaluation, we confirmed that, in comparison with the case using a single camera, the accuracy of gaze estimation was improved by switching among the cameras according to the position of the local user.
This paper presents an efficient computational algorithm for selecting the optimal generation mix considering CO2 emissions. To demonstrate the effectiveness and feasibility of the proposed method, a fundamental study of the evaluation of the optimal generation mix for controlling CO2 emissions is indicated. Furthermore, by using a parametric analysis which considers load characteristics as parameters, a general trend for the optimal generation mix which is affected by controlling CO2 can be derived. The proposed method is based on an optimization method known as simulated annealing. In the method, solutions in a generation mix problem are equivalent to state of a physical system, and the cost of a solution is equivalent to the energy of a state. The proposed method can easily accommodate not only CO2 emissions but also many practical constraints of generation expansion planning, such as integer solutions of unit capacities, condition of existing units, and so on. Case studies with various annual load patterns (combinations of annual load factors and the shapes of annual load duration curve) are presented and discussed. Consequently, a general trend for selecting generation technologies that should be added to a power system is derived, i.e., a useful guideline for studying generation expansion planning under controlling CO2 emissions can be provided. 相似文献
We have studied the development of a new procedure based on atomic force microscopy (AFM) for the analysis of metaphase chromosome. The aim of this study was to obtain detailed information about the specific locations of genes on the metaphase chromosome. In this research, we performed the manipulation of the metaphase chromosome by using novel AFM probes to obtain chromosome fragments of a smaller size than the ones obtained using the conventional methods, such as glass microneedles. We could pick up the fragment of the metaphase chromosome dissected by the knife-edged probe by using our tweezers-type probe. 相似文献
Fractionated samples of d,l-poly(lactic acid) (PLA) were prepared and the dielectric normal mode relaxation was studied for dilute and semi-dilute solutions of the PLA in a good solvent benzene. Results indicate that in the dilute regime the normal mode relaxation time is proportional to [η]Mw in agreement with the Rouse-Zimm theory, where [η] and Mw denote the intrinsic viscosity and weight average molecular weight, respectively. The dielectric relaxation strength which is proportional to the mean square end-to-end distance 〈r2〉 increases with increasing Mw with the power of 2ν, where ν is the excluded volume parameter determined from [η]. The relaxation time in the semi-dilute regime increases with increasing concentration C due to increases of the entanglement density and the friction coefficient. The relaxation time corrected to the iso-friction state agrees approximately with the dynamic scaling theories. The relaxation strength decreases with increasing concentration indicating that 〈r2〉 decreases on account of the screening of the excluded volume effect. The concentration dependence of 〈r2〉 agrees approximately with the scaling theory proposed by Daoud and Jannink. 相似文献
The Mg-Ca binary alloys in the Mg-Mg2Ca two-phase region show little precipitation hardening by aging. However, the Mg-Ca alloys microalloyed with Al and Zn result in notable age hardening because of the formation of metastable, internally ordered, plate-like Guinier?CPreston (GP) zones on the basal plane. To enhance the age-hardening response, we explored microalloying elements that can alter the habit plane from basal to prismatic. We found that an indium addition causes the homogeneous precipitation of thin plates on prismatic planes, resulting in a pronounced age-hardening response. Based on transmission electron microscopy and atom probe analysis results, we discuss the structure of the GP zones and the possible origin of the habit plane alternation. 相似文献
Cu(In,Ga)Se2 (CIGS) thin films were grown by the three-stage process using a rf-plasma cracked Se-radical beam source. CuGaSe2 (CGS) films grown at a maximum substrate temperature of 550 °C and CuInSe2 (CIS) and CIGS films grown at the lower temperature of 400 °C exhibited highly dense surfaces and large grain size compared with films grown using a conventional Se-evaporative source. This result is attributed to the modification of the growth kinetics due to the presence of active Se-radical species and enhanced surface migration during growth. The effect on CIGS film properties and solar cell performance has been investigated. Enhancements in the cell efficiencies of 400 °C-grown CIS and CIGS solar cells have been demonstrated using a Se-radical source. 相似文献
The first stage 600 kW system of Hokuto Mega-solar Project has been installed in Yamanashi Prefecture, Japan in 2008. The outline and the developing target of the project are introduced first and some results that have been provided so far are discussed in this paper. 相似文献
We designed a simple and efficient inlet system to act as an interface between samples at atmospheric pressure and the high vacuum inside a mass spectrometer. The newly designed stainless steel orifice leak sample inlet system is simple and rugged and fulfills all the basic requirements. With this inlet system coupled with a lithium ion attachment mass spectrometer, it is possible to detect any chemical species at atmospheric pressure, including radical intermediates, on a real-time basis. For illustrative purposes, the sampling efficiency of the inlet probe coupled with a lithium ion attachment mass spectrometer is discussed for laboratory air and polyethylene pyrolysis. 相似文献