Investigation of environmental change pattern in Japan

The author has identified the following significant results. In the Plains of Tokachi, where the scale of agricultural field was comparatively large in Japan, LANDSAT data with its accuracy have proved to be useful enough to observe the actual condition of agricultural land use and changes more accurately than present methods. Species and ages of grasses in pasture were identified and soils were classified into several types. The actual land cover and ecological environment were remarkably changeable at the rapidly industrialized area by the urbanization in the flat plane and also by the forest works and road construction in the mountainous area. The practical use of the recognition results was proved as the base map of the field survey or the retouching work of the vegetation and land use. There was a 10% cut in cost, labor, and time. Vegetation cover in Tokyo districts was estimated by both the multiregression model and the parametric model. Multicorrelation coefficient between observed value and estimated value was 0.87 and standard deviation was + or - 15%. Vegetation cover in Tokyo was mapped into five levels with equal intervals of 20%

Optical Thin Films and Structures

The book is devoted to the design, application and characterization of thin films and structures, with special emphasis on optical applications. It comprises ten papers—five featured and five regular—authored by scientists all over the world. Diverse materials are studied and their possible applications are demonstrated and discussed—transparent conductive coatings and structures from ZnO doped with Al and Ga and Ti-doped SnO2, polymers and nanosized zeolite thin films for optical sensing, TiO2 with linear and nonlinear optical properties, organic diamagnetic materials, broadband optical coatings, CrWN glass molding coatings, and silicon on insulator waveguides

Physical Modeling of Photoelectrochemical Hydrogen Production Devices

Solar-powered water splitting with photoelectrochemical (PEC) devices is a promising method to simultaneously harvest and store solar energy at a large scale. Highly efficient small prototype PEC devices reported recently demonstrate a move from basic material research toward design and engineering of complete devices and systems. The increased interest in engineering calls for a better understanding about the operational details of PEC devices at different length scales. The relevant physical phenomena and the properties of typical materials are well-known for separate device components, but their interaction in a complete PEC cell has received less attention. Coupled physical models are useful for studying these interactions and understanding the device operation as a whole and for optimizing the devices. We review the central physical processes in solar-powered water splitting cells and the physical models used in their theoretical simulations. Our focus is in particular on how different physical processes have been coupled together to construct device models and how different electrode and device geometries have been taken into account in them. Reflecting on the literature we discuss future opportunities and challenges in the modeling of PEC cells.Peer reviewe

Quantitative Estimation of Surface Soil Moisture in Agricultural Landscapes using Spaceborne Synthetic Aperture Radar Imaging at Different Frequencies and Polarizations

Soil moisture and its distribution in space and time plays an important role in the surface energy balance at the soil-atmosphere interface. It is a key variable influencing the partitioning of solar energy into latent and sensible heat flux as well as the partitioning of precipitation into runoff and percolation. Due to their large spatial variability, estimation of spatial patterns of soil moisture from field measurements is difficult and not feasible for large scale analyses. In the past decades, Synthetic Aperture Radar (SAR) remote sensing has proven its potential to quantitatively estimate near surface soil moisture at high spatial resolutions. Since the knowledge of the basic SAR concepts is important to understand the impact of different natural terrain features on the quantitative estimation of soil moisture and other surface parameters, the fundamental principles of synthetic aperture radar imaging are discussed. Also the two spaceborne SAR missions whose data was used in this study, the ENVISAT of the European Space Agency (ESA) and the ALOS of the Japanese Aerospace Exploration Agency (JAXA), are introduced. Subsequently, the two essential surface properties in the field of radar remote sensing, surface soil moisture and surface roughness are defined, and the established methods of their measurement are described. The in situ data used in this study, as well as the research area, the River Rur catchment, with the individual test sites where the data was collected between 2007 and 2010, are specified. On this basis, the important scattering theories in radar polarimetry are discussed and their application is demonstrated using novel polarimetric ALOS/PALSAR data. A critical review of different classical approaches to invert soil moisture from SAR imaging is provided. Five prevalent models have been chosen with the aim to provide an overview of the evolution of ideas and techniques in the field of soil moisture estimation from active microwave data. As the core of this work, a new semi-empirical model for the inversion of surface soil moisture from dual polarimetric L-band SAR data is introduced. This novel approach utilizes advanced polarimetric decomposition techniques to correct for the disturbing effects from surface roughness and vegetation on the soil moisture retrieval without the use of a priori knowledge. The land use specific algorithms for bare soil, grassland, sugar beet, and winter wheat allow quantitative estimations with accuracies in the order of 4 Vol.-%. Application of remotely sensed soil moisture patterns is demonstrated on the basis of mesoscale SAR data by investigating the variability of soil moisture patterns at different spatial scales ranging from field scale to catchment scale. The results show that the variability of surface soil moisture decreases with increasing wetness states at all scales. Finally, the conclusions from this dissertational research are summarized and future perspectives on how to extend the proposed model by means of improved ground based measurements and upcoming advances in sensor technology are discussed. The results obtained in this thesis lead to the conclusion that state-of-the-art spaceborne dual polarimetric L-band SAR systems are not only suitable to accurately retrieve surface soil moisture contents of bare as well as of vegetated agricultural fields and grassland, but for the first time also allow investigating within-field spatial heterogeneities from space

Characterization of the Earth\u27s surface and atmosphere for multispectral and hyperspectral thermal imagery

The goal of this research was to develop a new approach to solve the inverse problem of thermal remote sensing of the Earth. This problem falls under a large class of inverse problems that are ill-conditioned because there are many more unknowns than observations. The approach is based on a multivariate analysis technique known as Canonical Correlation Analysis (CCA). By collecting two ensembles of observations, it is possible to find the latent dimensionality where the data are maximally correlated. This produces a reduced and orthogonal space where the problem is not ill-conditioned. In this research, CCA was used to extract atmospheric physical parameters such as temperature and water vapor profiles from multispectral and hyperspectral thermal imagery. CCA was also used to infer atmospheric optical properties such as spectral transmission, upwelled radiance, and downwelled radiance. These properties were used to compensate images for atmospheric effects and retrieve surface temperature and emissivity. Results obtained from MODTRAN simulations, the MODerate resolution Imaging Spectrometer (MODIS) Airborne Sensor (MAS), and the MODIS and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) (MASTER) airborne sensor show that it is feasible to retrieve land surface temperature and emissivity with 1.0 K and 0.01 accuracies, respectively

Colour and Colorimetry Multidisciplinary Contributions Vol. XIb

It is well known that the subject of colour has an impact on a range of disciplines. Colour has been studied in depth for many centuries, and as well as contributing to theoretical and scientific knowledge, there have been significant developments in applied colour research, which has many implications for the wider socio-economic community. At the 7th Convention of Colorimetry in Parma, on the 1st October 2004, as an evolution of the previous SIOF Group of Colorimetry and Reflectoscopy founded in 1995, the "Gruppo del Colore" was established. The objective was to encourage multi and interdisciplinary collaboration and networking between people in Italy that addresses problems and issues on colour and illumination from a professional, cultural and scientific point of view. On the 16th of September 2011 in Rome, in occasion of the VII Color Conference, the members assembly decided to vote for the autonomy of the group. The autonomy of the Association has been achieved in early 2012. These are the proceedings of the English sessions of the XI Conferenza del Colore

Measurement techniques and instruments suitable for life-prediction testing of photovoltaic arrays

Array failure modes, relevant materials property changes, and primary degradation mechanisms are discussed as a prerequisite to identifying suitable measurement techniques and instruments. Candidate techniques and instruments are identified on the basis of extensive reviews of published and unpublished information. These methods are organized in six measurement categories - chemical, electrical, optical, thermal, mechanical, and other physicals. Using specified evaluation criteria, the most promising techniques and instruments for use in life prediction tests of arrays were selected

THERMOPHOTOVOLTAIC DEVICES AND INFRARED PHOTODETECTORS BASED ON INTERBAND CASCADE STRUCTURES

Mid-infrared (IR) optoelectronic devices form the basis for many practical applications such as thermophotovoltaic (TPV) energy conversion, gas sensing, thermal imaging, medical diagnostics, free-space communications, infrared countermeasures and IR illumination. The mid-IR device family based on interband cascade (IC) structures includes IC lasers (ICLs), ICTPV cells and IC infrared photodetectors (ICIPs). These are special types of multistage devices whose operation is made possible by the unique properties of the 6.1 Å material system: InAs, GaSb and AlSb, and their related alloys. One of the key properties is the type-II broken-gap alignment between InAs and GaSb. In multistage ICTPV cells and ICIPs, electrons must undergo multiple interband excitations in order to travel between the electrical contacts. This means that the transport of a single electron requires multiple photons, which reverses the situation in ICLs where a single electron can generate multiple photons. Counterintuitively, this transport feature in ICTPV cells and ICIPs is conducive to improving device performance by enhancing the open-circuit voltage in ICTPV cells and suppressing the noise in ICIPs. Furthermore, the collection efficiency of photo-generated carriers in multistage IC devices can be significantly improved by thinning the absorbers in individual stages. Collectively, these advantages make IC structures an attractive choice for narrow bandgap optoelectronic devices, especially for operation at high temperatures. One focus of this dissertation is to outline and demonstrate the advantages provided by IC structures, both in theory and experiment. Another focus of this dissertation is to obtain a better understanding of the physics of IC devices and gain insights into their operation. Theoretical studies of single-absorber and multistage ICTPV cells are presented. The limitations in efficiency are understood by considering several important practical factors. These factors are identified to be closely associated with a short carrier lifetime, high dark saturation current density, small absorption coefficient, and limited diffusion length. The multistage IC architecture is shown to be able to overcome the diffusion length limitation that is responsible for the low quantum efficiency (QE) in single-absorber TPV cells. This ability of the IC architecture offers the opportunity to enhance conversion efficiency by about 10% for wide ranges of aL (product of absorption coefficient and diffusion length) and bandgaps, resulting in a particle conversion efficiency approaching 100%. The illustrated theoretical advantage of multistage IC structures is confirmed experimentally in a comparative study of three fabricated TPV devices, one with a single absorber and two that are multistage IC structures. The bandgap of the InAs/GaSb type-II superlattices (T2SLs) in the three devices is close to 0.2 eV at 300 K. The extracted collection efficiency is considerably higher in multistage IC devices than in the single-absorber device. To further investigate the prospects of IC TPV cells, detailed characterization and performance analyses of two sets of four IC devices with similar bandgaps are performed. The four different configurations enable a comparative study that shows how device performance is affected by material quality variations, as well as by current mismatch between stages and collection efficiency. The carrier lifetime advantage of IC devices over another family of cascade devices, namely quantum cascade (QC) devices, is manifested in the saturation current density (J0). The values of J0 extracted using a semi-empirical model, are more than one order of magnitude lower in IC devices than in QC devices. The significance of J0 on the performances of IR detectors and TPV cells is apparent in a comparison of the measured detectivity (D*) and the estimated open-circuit voltage (Voc). To extract the carrier lifetime in IC devices, a simple and effective electrical method is developed. This method is more generally applicable and considers the parasitic shunt and series resistances found in practical devices. It provides a simple way to extract the carrier lifetime in InAs/GaSb T2SLs in a wide range of operating temperatures. The effect of current mismatch on the performance of ICIPs is investigated using two sets of devices with current-matched and noncurrent-matched configurations. It is shown that current matching is necessary to achieve maximum utilization of absorbed photons for an optimal responsivity. The detectivities of both sets of devices are comparable largely due to the occurrence of a substantial electrical gain in noncurrent-matched ICIPs. The electrical gain is shown to be a ubiquitous property for noncurrent-matched ICIPs through the study of another three devices. To unlock the mechanism underlying electrical gain, a theory is developed for a quantitative description and the calculations are in good agreement with the experimental results

Depigmentation

Depigmentation, lightening of the skin and mucosa, can be caused by local or systemic conditions, and there may be partial or complete loss of pigment. Although depigmented patches may not matter in Caucasians, it is very serious for pigmented skin.Depigmentation can also be a therapeutic goal for cosmetic treatment. Many vitiligo patients who received depigmentation treatment experienced paradoxical jealousy because of their clean white skin. To improve facial blemishes, many people spend their money on laser, chemical peel, and cosmetic treatments. In this book, we focus on two opposite sides of depigmentation: diseases of depigmentation and therapeutic depigmentation presented by global experts