The Statical Characteristics of the Wall Reattachment Fluidic Devices

This study is concerned with a developed method for obtaining the quantitative relations between the input or output characteristics and the geometric parameters of the wall reattachment fiuidic devices. In this report, it is shown analytically and experimentally that the characteristics can be represented by the functions, dependent on the geometric parameters only, with non dimensional quantities, if the Reynolds number at the main jet nozzle is sufficiently large. Accordingly, the quantitative relations of the geometric parameters may be analyzed more easily

On the Manual Control System

The method of the harmonic analysis of the human operator's characteristics by means of an analog computer is described. The human operator's characteristics in the closed loop system are described by vector locus. The human operator controls in response to the sine wave input so as to make constant the gain in the closed loop system. In accordance with the change of the input frequency, the operator changes his control action. Consequently the transfer function of the human operator's characteristics is too complex and difficult to be described by a linear element

A Study of the Manual Control System

An analysis is attempted of the human operator's responses to the sinusoidal input and the random input. The human operator's characteristics in the closed loop system are represented by the Bode diagram. This diagram shows that the human operator's response to the random input containing only those frequency components lower than 4 rad/s is almost in accordance with his response to the siunsoidal input of the same frequency range

Analysis of Warren's Fluidic Counter

Though the Warren's fluidic counter has a very simple construction, the matching problems of the main jet supply pressure with the input pulse may take place and so there may be some working conditions under which this counter cannot work. Up to now, these matching problem have been hardly investigated. In this study the following things were systematically investigated : the static and dynamic characteristics of the memory and the control flip-flops with different geometric parameters, the behavior of the counter which are constructed by two of them, and finally the fow in the counter. The obtained results are as follows : (1) Under some clear and accurate conditions, the Warren's counter works satisfactory without any au iliary circuit. (2) In the control part, the input pulse flow don't reattach on any side wall, but branches into both output ports. (3) The necessary condition under which the Warren's counter behaves successfully is as follows : (1-2α)Q(i)>Q(ms), where α is the distribution factor of the control part, is the input pulse flow rate and is the switching control flow rate of the memory part

Effects of Pointed Splitter Position on Attached Jet Switching

In this report, the effects of splitter position on the attached jet were experimentally investigated for the purpose of discussing the applicability of a usual mathematical model without splitter. As results, the followings were confirmed, (l) For the splitter distance shorter than the critical distance, the pressure in the bubble lowers and the jet radius of curvature shortens. (2) At the ratio L(s)/D=4~5, the switching control flow rate becomes maximum. And bordering this value, the effects of splitter position on the switching are quite conversely. For the splitter distance longer than the above value, the switching control flow rate decreases, as increasing the distance. (3) For the splitter distance of 1.5~2 times critical distance, the switching is almost never affected by the splitter

Deep 15um AKARI observations in the CDFS: estimating dust luminosities for a MIR-selected sample and for Lyman Break Galaxies and the evolution of L(dust)/L(UV) with the redshift

Deep observations of the CDFS have been secured at 15um with AKARI/IRC infrared space telescope (ESA open time). From these observations, we define a sample of MIR-selected galaxies at 15um and we also obtain 15um flux densities for a sample of LBGs at z=1 already observed at 24um with Spitzer/MIPS. Number counts for the MIR-selected sample show a bump around a 15um flux density of 0.2mJy that can be attributed to galaxies at z>0.4 and at z>0.8 for the fainter part of the bump. This bump seems to be shifted as compared to other works and a possible origin can be the Cosmic variance. Thanks to this dataset, we have tested, on the two above samples at z=1, the validity of the conversions from monochromatic luminosities nu.f(nu) at a rest-frame wavelength of 8um by a comparison with total dust luminosities estimated from Spitzer rest-frame 12um data that we use as a reference. We find that the 8um dust luminosities are not all consistent and that some of them are better when compared to L(dust) evaluated from longer wavelength luminosities. We also find that the rest-frame 8um luminosities provide globally good estimates of L(dust). By comparing our data for the two samples to several libraries of SEDs, we find that models can explain the diversity of the observed f(24)/f(15) ratio quite reasonably for the MIR-selected sample and better for the LBG sample which are less dispersed than the MIR selection. However, when we analyse the luminosity dependence of this ratio, we find important discrepancies. Finally, we revisit the evolution of L(dust)/L(UV) ratio with the redshift z by re-calibrating previous L(dust) at z=2 based on our results and added new data points at higher redshifts. The decreasing trend is amplified as compared to the previous estimate.Comment: Paper accepted for publication in PAS

A Method of Cubic Object Feature Extraction

How to reduce and simplify the calculation for image recognition is a very attractive and important issue in order to realize the real time control of a robot based on the image recognition results. This paper describes a method of extracting 2 - dimensional geometrical features of cubic objects based on the normal vector distributions from the visual information obtained with the laser range finder to reduce the calculation of the image recognition. In this research a laser beam is scanned in the horizontal plane to which the cubic objects stand vertically and the laser spot is detected with a TV camera every sampling time. These spots make an intermittent locus which includes some special lines corresponding to the cubic objects. To extract the features of the cubic objects, we utilize the normal vectors formed on the locus. If some normal vectors distribute in the same direction and the origin of the normal vectors are very close to their neighbor's, these normal vectors can be classified into the same class, -the straight line class. Because the normal vectors on the neighbor surfaces of the cubic objects are vertical to each other, we use this property to determine the pair of straight lines which belong to the cubic objects. Making the histogram based on the normal vectors with the same direction, we obtain the peaks which are supported by the points on the cubic object surfaces. Then, the points can be extracted from the set of points on the whole locus inversely according to the relations with the peaks and the features of the cubic object can be extracted by applying method of least square to these extracted points. The experiments proved the availability of the proposed processing algorithm

Effects of Wall Length and Vent on Attaching Jet and Its Switching

The effects of some geometries peculiar to the wallattachment fluidic devices on the attaching jet flow and the switching mechanism were experimentally made clear. And the propriety of the analytical mOdel, which has been used for the theoretical study of these devices, was investigated. The results can be summarized as follows: 1) The existing analytical model of the attaching jet flow is not applicable to the case of relatively short wall length of vent distance. 2) The attaching jet flow never detaches from a sufficiently long side wall with vent. 3) The switching mechanism of the vent type device is always the opposite wall switching. 4) From the viewpoint of the output characteristics of the device, the vent distance has a lower limit in relation to the vent width

Dynamic Switching of Wall-Reattachment Fluidic Device

Effect of the geometrical configuration of wall-reattachment fluidic device on the switching dynamics, the switching time, and its dispersion, was investigated experimentally by using a large scale model. The results obtained can be summarized as follows: 1) The switching time, its dispersion, and switching probability depend upon the connection of the input to the control port. 2) Effect of the vent and splitter on the jet in dynamic switching is explained commonly by using the margin of a given control flow rate to the switching control flow rate. 3) The switching time ,decreases as input increases, whereas its dispersion remains constant except for small input