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In this paper, a two-dimensional sliding block model --discretized in slices- is presented, in which the geometrical, mechanical and rheological variables of the landslide are considered in order to analyse the soil landslide kinematic behaviour. The movement of the sliding mass is presented as a system of adjacent blocks; the movement strength is given by the Coulombviscous rheological model, where the friction and viscous components are considered, represented by a parallel system of a slider and a damper, respectively. The movement equation of the model corresponds to a second order differential equation, which was solved by the finite difference method, obtaining an explicit equation to know the displacement, velocity and acceleration of each block. An algorithm was developed in MATLAB® software, where movement equations were programmed to obtain results of the sliding kinematics. With the algorithm developed it was possible to make a sensitivity analysis to the parameters of the model. This was implemented in the problem of the sliding block at infinity slope, where it was possible to know the influence of each of the parameters of the model. The model has also been applied to the Hiegaesi landslide occurred in Japan in 1998, where the kinematic behaviour has been analysed in the model, regarding the records reported. However, further research is needed in order to apply the published model for prediction of the kinematic behaviour of landslides due to different limitations discussed in this paper. [ABSTRACT FROM AUTHOR]

Abstract: We developed a new back-projection method that uses teleseismic P-waveforms to integrate the direct P-phase with reflected phases from structural discontinuities near the source and used it to estimate the spatiotemporal distribution of the seismic energy release of the 2011 Tohoku-oki earthquake. We projected a normalized cross-correlation of observed waveforms with corresponding Green''s functions onto the seismic source region to obtain a high-resolution image of the seismic energy release. Applying this method to teleseismic P-waveform data of the 2011 Tohoku-oki earthquake, we obtained spatiotemporal distributions of seismic energy release for two frequency bands, a low-frequency dataset and a high-frequency dataset. We showed that the energy radiated in the dip direction was strongly frequency dependent. The area of major high-frequency seismic radiation extended only downdip from the hypocenter, whereas the area of major low-frequency seismic radiation propagated both downdip and updip from the hypocenter. We detected a large release of seismic energy near the Japan Trench in the area of maximum slip, which was also the source area of the gigantic tsunami, when we used only the low-frequency dataset. The timing of this large seismic energy release corresponded to an episode of smooth and rapid slip near the Japan Trench, and reflects the strong dependence of the seismic energy distribution obtained on the frequency band of the input waveform dataset. The episode of smooth and rapid slip may have been the trigger for a release of roughly all of the accumulated elastic strain in the seismic source region of the 2011 Tohoku-oki earthquake. [Copyright &y& Elsevier]

Summary: This paper investigates whether and how foreign aid facilitates foreign direct investment (FDI) flows into less developed countries. We employ a large data set of source-recipient country pairs and conduct gravity equation-type estimation. Our empirical methodology enables us to examine an effect through which aid from a donor country promotes FDI from the same donor in particular, which we call a “vanguard effect.” We find that foreign aid in general does not have any significant effect on FDI. However, when we allow for differences in the size of aid effects across donor countries, we find robust evidence that foreign aid from Japan in particular has a vanguard effect, i.e., Japanese aid promotes FDI from Japan but does not attract FDI from other countries. [Copyright &y& Elsevier]

Human T-cell leukemia virus type I (HTLV-I) is a retrovirus that causes adult T-cell leukemia, and the distribution of HTLV-I carriers is endemically biased, e.g. in Japan the density of carriers is high in Kyushu and Okinawa. In order to consider population dynamics over long times taking account of an increase and a decrease of a population we propose a continuous-time HTLV-I model. The model describes population dynamics of carrier numbers and that of carrier proportions, and theoretical results about an increase and a decrease of carriers are obtained. The present approach derives an explanation of the biased distribution of carriers in Japan. [ABSTRACT FROM AUTHOR]

Abstract-This paper investigates the correlation between max- imum temperature increases and peak spatial-average specific ab- sorption rates (SARs), calculated by different average schemes and masses. For evaluating the effect of mass on the correlation prop- erly, a three-dimensional Green's function is presented. From our computational investigation, no best average mass for peak spatial- average SAR exist from the aspect of the correlation with maximum temperature increase. This is attributed to the frequency dependent penetration depth of EM waves. Maximum temperature increase in the head including the pinna is reasonably correlated with peak spatial-average SARs for most average schemes and masses consid- ered in this paper. Maximum temperature increase in the head only (excluding the pinna) is reasonably correlated with peak 1O-g SARs for the average schemes considered in this paper. The rationale for this result is explained using the Green's function. The point to be stressed here is that the slope correlating them is largely dependent on the average scheme and mass. Additionally, good agreement is observed in the slopes obtained by using two head models, which have been developed at Osaka University and Nagoya Institute of Technology. However, weak correlation is observed for the brain, which is caused by the difference of the positions where peak SAR and maximum temperature increase appear. The 95th percentile values of the slope correlating maximum temperature increases in the head or brain and peak spatial-average SAR are quantified for different average schemes and masses. [ABSTRACT FROM AUTHOR]

Although a reflector antenna with a single reflecting surface called a doubly curved reflector, based on a reflector shaping technology that uses geometrical optics approximation, was effective in synthesizing a fan-beam, there was ambiguity in the reflector design technique. This paper shows that an exact and unique solution in the sense of geometrical optics is obtainable as a solution of an ordinary differential equation. It then generalizes the doubly curved reflector design method, extending it to the synthesis of a curved fan-beam whose beam footprint has curvature. [ABSTRACT FROM AUTHOR]

In this note we extend the Gaussian estimation of two factor CKLS and CIR models recently considered in Nowman, K. B. (2001, Gaussian estimation and forecasting of multi-factor term structure models with an application to Japan and the United Kingdom, Asia Pacif. Financ. Markets 8, 23–34) to include feedback effects in the conditional mean as was originally formulated in general continuous time models by Bergstrom, A. R. (1966, Non-recursive models as discrete approximations to systems of stochastic differential equations, Econometrica 34, 173–182) with constant volatility. We use the exact discrete model of Bergstrom, A. R. (1966, Non-recursive models as discrete approximations to systems of stochastic differential equations, Econometrica 34, 173–182) to estimate the parameters which was first used by Brennan, M. J. and Schwartz, E. S. (1979, A continuous time approach to the pricing of bonds, J. Bank. Financ. 3, 133–155) to estimate their two factor interest model but incorporating the assumption of Nowman, K. B. (1997, Gaussian estimation of single-factor continuous time models of the term structure of interest rates, J. Financ. 52, 1695–1706; 2001, Gaussian estimation and forecasting of multi-factor term structure models with an application to Japan and the United Kingdom, Asia Pacif. Financ. Markets 8, 23–34). An application to monthly Japanese Euro currency rates indicates some evidence of feedback from the 1-year rate to the 1-month rate in both the CKLS and CIR models. We also find a low level-volatility effect supporting Nowman, K. B. (2001, Gaussian estimation and forecasting of multi-factor term structure models with an application to Japan and the United Kingdom, Asia Pacif. Financ. Markets 8, 23–34). [ABSTRACT FROM AUTHOR]

The ringing choke converter is widely used as an electronic power supply with a small capacity. A number of works have been published on the feedback systems for adjustment of output voltage. NO sufficient analysis, however, has been undertaken on the static and dynamic characteristics. In this paper, a nonlinear differential equation describing the basic operation is first derived. Next, from a small signal model obtained from this differential equation, a loop transfer function of the converter is derived. Further, the transfer function for an input variation and a load variation under regulation have been derived. As a result, the characteristic equation becomes linear and it is shown that the converter is extremely stable. The dynamic characteristic parameters of the ringing choke converter are found different from those of the conventional reactor current discontinuity mode converter. Both the gain bandwidth product of the loop transfer function and that of the transfer function of the output voltage fluctuations for the input voltage fluctuations under regulation are smaller in the ringing choke converter than in the reactor current discontinuous mode converter. It is found that the ringing choke converter is less susceptible to the input voltage fluctuations and operates with a greater stability than the reactor current discontinuous mode converter. [ABSTRACT FROM AUTHOR]

The article presents a study which uses a deterministic model to describe the process of deforestation using differential equation in modeling deforestation by human population interactions. It applies theoretical relation and possible models to the grid cell data in Hiroshima Prefecture in Japan and relative appropriateness of the model was evaluated by Akaike's information criterion (AIC). It demonstrates that the theoretical relation agrees among many other models in comparison.