Applicability of the Magnification Equation of Lens for Slope Survey

Photography is often used in geological survey, mining engineering or civil engineering to measure the length or width of an object by placing another object such as a scale, a hammer or a cigarette box next to the object. But, it is difficult to place a scale nearby the object when the object is too far and high or too dangerous to get to. In this study, practical applicability of the magnification equation of lens for indirect calculation of the length of a photographed object was examined. From this study, it was found that the applicable distance for the use of the magnification equation of lens was 84 m, even when the focal length was 36mm, and that the applicable distance was more than 300 m with the lens focal length being longer than 100 mm. Moreover, falling behavior, impact load and energy of a rock fall could be calculated readily using obtained information from a photograph.     

An active low-pass filter using two capacitive double-layer uniformly distributed RC lines

In this paper we propose an active circuit consisting of two capacitive double-layer uniformly distributed RC lines and an operational amplifier, and present conditions under which the circuit works as the low-pass filter. Furthermore, we present a method for designing the low-pass filter and give a design example where simulation results are included.     

Moderately high speed impact of two identical spheres

This paper deals with impacts between two identical spheres in moderately high speed range. Impact of spheres is one of basic problems in mechanical dynamics. Severity of impact is generally characterized by the coefficient of restitution. However, influence of material property on the coefficient of restitution has not been clarified yet. The authors previously investigated direct central impacts of two identical spheres in low speed range and revealed that strain rate sensitivity of material properties could not be ignored even in the low speed impacts. Therefore, this paper investigates the direct central impact of two identical spheres in higher speed range. The impact experiments were performed in range of impact speed 10 m/s–20 m/s by using air-gun setup. It was confirmed that the expressions for the coefficient of restitution and the contact time derived from the low speed impact remained effective in the moderately high speed range. Then numerical simulations by using Finite Element Method (F.E.M) have been carried out, in which the material properties and the strain rate effect were taken into account. The coefficient of restitution, contact time, sphere’s compression and contact circle diameter obtained by experiments and F.E.M. were compared and they matched well. Contact pressure distributions at maximum contact force were investigated. The contact pressure at sphere center varied little with impact speed but the contact pressure increased with impact speed near contact edge. Theoretical expression for prediction of the coefficient of restitution proposed by C. Thornton was examined to the experimental results of this study. To provide an accurate prediction, it is necessary to estimate the contact pressure depending on material properties. Finally, the Meyer analysis was applied to the case of this study and it was found that the Meyer’s law holds in the moderately high speed impact between two identical spheres.     

Ionic liquid enables simple and rapid sample preparation of human culturing cells for scanning electron microscope analysis

Ionic liquid is a kind of salt that stays in a molten state even at room temperature. It does not vaporize at all in vacuum and facilitates electrical conductivity to the sample surfaces for observations with a scanning electron microscope (SEM). In this study, we used an ionic liquid in SEM for the first time to observe fixed human culture cells. The condition for the cell culture using wrapping sheets and SEM settings were varied to elucidate the optimized protocol. Compared to samples prepared by the conventional way, the ionic liquid‐treatment of samples gave SEM images of the cellular ultra structures in more detail, enabling observation of microvilli that made bridges between separated cells. In addition, the ionic liquid treatment is less time consuming as well as less laborious compared with the conventional way that includes dehydration, drying, and conductivity treatments. Totally, we concluded the ionic liquid is a useful reagent for SEM sample preparation. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.     

Three-layer flow membrane system on a microchip for investigation of molecular transport

A stable three-layer flow system, water/organic solvent/water, has been successfully applied for the first time in a microchannel to get rapid transport through an organic liquid membrane. In the continuous laminar flow region, the analyte (methyl red) was rapidly extracted across the microchannel from the donor to the acceptor phase through the organic solvent phase (cyclohexane). Thermal lens microscopy was used to monitor the process. The thickness of the organic phase, sandwiched by the two aqueous phases, was approximately 64 microm, and it was considered as a thin liquid organic membrane. Permeability studies showed the effects of molecular diffusion, layer thickness, and organic solvent-water partition coefficient on the molecular transport. In the microchip, complete equilibration was achieved in several seconds, in contrast to a conventionally used apparatus, where it takes tens of minutes. The thickness of the organic and aqueous boundary layers was defined as equal to the microchannel dimensions, and the organic solvent-water partition coefficient was determined on a microchip using the liquid/liquid extraction system. Experimental data on molecular transport across the organic membrane were in agreement with the calculated permeability based on the three-compartment water/organic solvent/water model. This kind of experiment can be performed only in a microspace, and the system can be considered as a potential biological membrane for future in vitro study of drug transport.     

Motion of an antiviral compound in a rhinovirus capsid under rotational symmetry boundary conditions

A molecular dynamics (MD) simulation of a complex of a rhinovirus protein shell referred to as a "capsid" and an anti-rhinovirus drug, WIN52084s, was performed under the rotational symmetry boundary conditions. For the simulation, the energy parameters of WIN52084s in all-atom approximations were determined by ab initio calculations using a 6-31G* basis set and the two-conformational two-stage restricted electrostatic potential fit method. The motion of WIN52084s and the capsid was focused on in the analysis of the trajectory of the simulation. The root mean square deviations of WIN52084s from the X-ray structure were decomposed to conformational, translational, and rotational components. The translation was further decomposed to radial, longitudinal, and lateral components. The conformation of WIN52084s was rigid, but moving in the pocket. The easiest path of motion for WlN52084s was on the longitudinal line, providing a track for the binding process required of the anti-rhinovirus drug to enter the pocket. The conformation of the pocket was also preserved in the simulation, although the position of the pocket in the capsid fluctuated in the lateral and radial directions.     

Detection method of the Kuroshio front using the satellite-derived chlorophyll-a images

Satellite-derived sea surface temperature (SST) has been providing high-resolution information of the oceanic front. However, in summer, increasing surface heating effects make SSTs uniform and the SST front disappears. The purpose of the present study is to examine applicability of satellite-derived surface chlorophyll-a (Chl-a) for detection of the Kuroshio front in the ocean south of Japan during the summer season.The Kuroshio surface front is formed between the Kuroshio water (KW) and the coastal water (CW) in the study area. Investigating accumulated in situ observations of SST and Chl-a, it is shown that the difference of Chl-a between KW and CW is increased in summer though that of SST becomes small. Using 76 pairs of cloud-free satellite-derived SST and Chl-a images with 0.01° spatial resolution, their seasonal variations are investigated through two-dimensional (2-D) histograms of Chl-a and SST. In summer, SST ranges from 25 to 30 °C and Chl-a ranges 0.03 to 0.4 mg/m³. Two peaks in the summer 2-D histogram correspond to wider KW and CW areas with rather uniform Chl-a and SST distributions. The peak values are extracted from the 2-D histograms and used to determine a threshold value dividing the KW and CW surface Chl-a during summer. It is found that the Chl-a concentration of 0.17 mg/m³ divides the extracted peaks into two groups, i.e., CW and KW except for a few peaks.The proposed Kuroshio-front detection method using the Chl-a images and the threshold value is examined using the satellite images and in situ data. The threshold contour superimposed in the summer Chl-a image distinctly separates the two representative waters in the ocean south of Japan. The front positions determined by the satellite-derived Chl-a, in situ SST, and in situ surface salinity transects along observation lines crossing the Kuroshio front agree with each other. Applying a traditional Kuroshio front index of temperature at 200 m depth, the capability of new Chl-a threshold in dividing two waters around the near-front area is quantitatively examined. Producing 74 match-ups of the satellite-derived Chl-a and 200-m temperature in the frontal zone, the dividing capability is evaluated quantitatively using the traditional Kuroshio-axis index. The detection capability of the proposed method is 82%, which can be considered high enough for practical applications.     

Market micro-structure analysis by multiagent simulation in X-Economy -- comparison among technical indices

We are developing an agent and server library referred to as X-Economy, by which we can execute multiagent simulations and network games for financial and economic systems. To this end, we analyzed the characteristics of network games in a financial context and compared them with traditional ones. X-Economy has also provided a new research direction in market micro-structure analysis. We executed several kinds of multiagent simulations for technical traders (indices) and obtained non-trivial suggestions regarding the relationship between the market randomness and the effectiveness of technical indices. For instance, the performance of complex technical indices seemed to deeply depend on the characteristics and nature of a market when a market became complex, i.e. it moved far from the Wiener process.