Disaster debris estimation using high-resolution polarimetric stereo-SAR

AbstractThis paper addresses the problem of debris estimation which is one of the most important initial challenges in the wake of a disaster like the Great East Japan Earthquake and Tsunami. Reasonable estimates of the debris have to be made available to decision makers as quickly as possible. Current approaches to obtain this information are far from being optimal as they usually rely on manual interpretation of optical imagery. We have developed a novel approach for the estimation of tsunami debris pile heights and volumes for improved emergency response. The method is based on a stereo-synthetic aperture radar (stereo-SAR) approach for very high-resolution polarimetric SAR. An advanced gradient-based optical-flow estimation technique is applied for optimal image coregistration of the low-coherence non-interferometric data resulting from the illumination from opposite directions and in different polarizations. By applying model based decomposition of the coherency matrix, only the odd bounce scattering contributions are used to optimize echo time computation. The method exclusively considers the relative height differences from the top of the piles to their base to achieve a very fine resolution in height estimation. To define the base, a reference point on non-debris-covered ground surface is located adjacent to the debris pile targets by exploiting the polarimetric scattering information. The proposed technique is validated using in situ data of real tsunami debris taken on a temporary debris management site in the tsunami affected area near Sendai city, Japan. The estimated height error is smaller than 0.6m RMSE. The good quality of derived pile heights allows for a voxel-based estimation of debris volumes with a RMSE of 1099m3. Advantages of the proposed method are fast computation time, and robust height and volume estimation of debris piles without the need for pre-event data or auxiliary information like DEM, topographic maps or GCPs

The Location of Financial Activities: The Impact of New Technologies and the Financial Crisis

The location of financial activities is traditionally characterized by a great deal of inertia. However, the boom in new information and communication technologies, the globalization of economies and the 2007-08 financial crisis have considerably modified the geography of finance. Financial globalization has, first of all, had a heavy impact on the level of spatial concentration / dispersion of activities. The dynamics have not acted in a uniform way – schematically speaking three levels can be distinguished. On the urban scale, financial activities have been spread out (suburbanization), while on the regional scale or the national scale, due to financial globalization, financial activities have been more tightly grouped. Lastly, on the international scale, a movement of dispersion has mainly been observed, along with a specialization of financial centers. The 2007-08 financial crisis might well accentuate this last effect and cause an upheaval in world hierarchy. Actually, the financial centers that are most elastic to the economic situation – London, New York and tax havens – are massively losing jobs, while the stock markets in Shanghai, Hong Kong and Bombay are now upstaging them as major players.Financial Geography, International Financial Centers, Globalization, Informational Externalities

The Effect of Participation in Government Consortia on the R&D Productivity of Firms: A Case Study of Robot Technology in Japan

This paper examines the effect of participation in government-sponsored R&D consortia on the R&D productivity of firms in the case of robot technology in Japan. We attempt to provide a new empirical analysis and discussions on the issue of government project evaluation by using indicators of the quality of patents, by investigating the impact of the evolution of government programs, and comparing government-sponsored R&D consortia with collaborative R&D among firms. Using indicators of the quality of patents which enables us to provide an estimation of quality-adjusted research productivity, we find that participation in government programs has a positive impact on the research productivity of participating firms, but the impact of participation became much higher after the design of government programs in this field changed in the late 1990s. Also, we find that participation in government-sponsored consortia has a greater impact on research productivity than participation in collaborative R&D among firms. This may support government involvement in R&D as a coordinator of R&D collaboration.industrial policy, robot thchnology, Japanese innovation system, collaborative R&D