ALBERT

Description: This article addresses the presupposition that mathematics is as effective as claimed and thus remove the quandary of Wigner??s ``miracle,???? leading to a non-Platonist viewpoint. Also revisits Hamming??s four propositions and show how they may indeed largely explain that there is no miracle, given a reduced level of mathematical effectiveness.

Description: The metalorganic chemical vapor deposition (MOCVD) technology for the growth of III–V compound semiconductors has been developed over the past 40+ years to become the dominant epitaxial materials technology for both research and production of light-emitting devices as well as many other optoelectronic devices. Because of the flexibility and control offered by this process, and the material quality produced by MOCVD, many important III–V devices have become commercially viable. This paper will describe the development of MOCVD for the growth of high-quality ultrathin layers and heterojunctions of III–V compound semiconductors, which are now commonly called “quantum wells (QWs),” and the optical devices, which exploit the unique properties of such layers, e.g., QW lasers and light-emitting diodes (LEDs).

Description: The demonstration of direct bandgap alloy semiconductor (GaAsP) visible (red) emitters by Nick Holonyak at General Electric in 1962 began the evolution of high-brightness LED technology. Today, high-brightness LEDs are a growing $12 billion business with applications which include traffic signals, automobiles, camera flash, display backlighting, and general illumination. This paper will discuss the key developments which enabled the evolution from the early red device with performance of less than 0.1 lumen/watt (lm/W) to today's devices with performance in excess of 100 lm/W. LEDs are now replacing conventional light sources for general lighting applications. By 2020, LEDs are expected to be the dominant technology for general illumination; the energy savings will be around 10% of the total electricity utilized, which is the equivalent of 50 large nuclear power plants for the United States alone.

Description: The double-heterostructure (DH) concept for lasers and light-emitting diodes (LEDs) grew out of the prelaser context of increasing the speed of the early bipolar junction transistors. The 1954 idea was to change the energy gap itself, with a graded-gap base, or a wide-gap emitter. This led to the 1957 more general concept of quasi-electric fields and potentials in structures with a position-dependent energy gap. This paper gives a personal chronological account of the evolution of these concepts toward the 1963 proposal of the DH laser, including some blind alleys and blunders along the way.

Description: The vertical-cavity surface-emitting laser (VCSEL) is becoming a key device in high-speed optical local area networks (LANs) and even wide-area networks (WANs). This device is also enabling ultraparallel data transfer in equipment and computer systems, including storage area networks (SANs) and wide optoelectronics fields. In this paper, we will review its physics and the progress of technology covering the spectral band from infrared to ultraviolet by featuring materials and fabrication technology. Performances such as threshold, output power, polarization, modulation, and reliability are introduced. Last, we will touch on its future prospects.

Description: The history of development for gallium–nitride-based light-emitting diodes (LEDs) is reviewed. We identify two broad developments in GaN-based LED technology: first, the key breakthroughs that enabled the development of GaN-based devices on foreign substrates like sapphire (first-generation LEDs), and, second, a new wave of devices benefiting from developments in GaN substrate manufacturing, which has led to native bulk-GaN-based LEDs with unprecedented performance characteristics that portend a disruptive shift in LED output power density and the corresponding cost of generating light.

Description: Semiconductor revolution of the 20th century determined not only technological, but also social development of the modern society. The precursors of modern semiconductor electronics were Oleg Losev's discoveries of “crystadine” and “light-emitting diode (LED)” nearly 100 years ago. Creation of the transistor and semiconductor laser and LED based on the homo p–n structure became the most decisive step. Semiconductor optoelectronics was born with the creation of GaAs and GaAsP lasers and “LED.” The possibility to control the type and level of conductivity and injection in p–n junctions was the seed from which semiconductor electronics developed. Heterostructures—“man-made crystals”—solved a more general problem: the necessity to control electron and photon fluxes in crystals. The development of physics and technology for semiconductor heterostructures resulted in drastic changes in our everyday life. It is hardly possible to imagine our recent life without double-heterostructure (DH) laser-based telecommunication systems, without efficient DH LEDs, heterostructure bipolar transistors, and high electron mobility transistors (HEMTs) for high-frequency applications. DH lasers were introduced in every household with CD players. Heterostructure solar cells have been widely used for space and terrestrial applications. The first proposals for heterostructures in semiconductor devices were made as early as in the 1950s, but the most important experimental results were received at the end of the 1960s when the first ideal AlGaAs heterostructures and low threshold room-temperature lasers, efficient heterostructure LEDs, and solar cells were created. Later semiconductor heterostructure became laboratories of low-dimension electron gases. Molecular-beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) technologies were the basis for the development of new structures, - ncluding superlattices, and for the industrial production of a large family of heterostructure semiconductor devices. Quantum dot (QD)-based optoelectronics as a modern trend in optoelectronics is the subject of a more detailed consideration.

Description: Since the discovery of III–V oxidation by Dallesasse and Holonyak in 1989, significant progress has been made, both technically and commercially, on the use of oxides in compound semiconductor devices. The process-induced modification of refractive index and conductivity allows control of the two carriers of information in optoelectronic systems, the photon and the electron, enabling wide-ranging device applications. Of great technical and commercial importance has been the use of oxidation for the fabrication of high-speed vertical-cavity surface-emitting lasers (VCSELs), first implemented by Deppe's group at The University of Texas at Austin (Austin, TX, USA). Here, the low refractive index III–V oxide's interaction with the optical modes inside the VCSEL creates an optimal overlap of gain and field, enabling lasers with ultralow threshold currents and desirable optical beam properties. The discovery of III–V oxidation, key technical milestones in the fabrication of photonic and electronic devices that use oxidation, and the application to VCSELs are reviewed.

Description: Large GaN single-crystal substrates with low dislocation density are the key materials for the commercial production of GaN-based laser diodes. We developed a new method to reduce the dislocations, named dislocation elimination by the epitaxial-growth with inverse-pyramidal pits (DEEP). A thick GaN film is epitaxially grown on a GaAs substrate with hydride vapor-phase epitaxy and then is separated from the GaAs substrate. The thick GaN layer grows with numerous large inverse-pyramidal pits. As the growth proceeds, dislocations in the GaN film are concentrated to the center of the pit and a wide area with low dislocation density is formed within the pit except the center area. To control the dislocation artificially, the position of the pits is fixed at a predetermined position by means of the selective growth of different polarity GaN film. This process was named as advanced DEEP (A-DEEP). GaN substrates with the A-DEEP method satisfied all the requirements for the violet laser diodes. We continued to develop new GaN substrates such as large-diameter c-plane substrates as well as nonpolar/semipolar GaN substrates. In particular, we overcame the green gap problem and developed the world's first true green laser diodes by selecting an optimal crystal plane.

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Description: The articles in this special issue focus on the history and development of light emitting diode (LED) technology and industry applications over the last fifty years.

Description: In this paper, an account is presented of the semiconductor, because of the energy gap bipolar with electron (e) and hole (h) conductivity, becoming ingeniously with little or no technology (Bardeen and Brattain, Dec. 1947) the transistor, a triode (at first just a germanium “base” crystal and a point contact “emitter” and “collector”), a low impedance “emitter” minority carrier input $({I}_{E})$ into a (the) vital central “base” active region, the base supporting along with essential recombination current ${I}_{B}$ $({I}_{B}〉0)$ carrier transport to a higher impedance “collector” output ${I}_{C}$ ( ${I}_{E}+{I}_{B}+{I}_{C}=0$ , ${I}_{C}/{I}_{E}=alphasim 0.9$ ), hence gain, thus revealing at last that a current $({I}_{B})$ can increase the electron–hole (e–h) population, and as a further consequence, yield band-to-band $({k}_{e}={k}_{h})$ excess carrier recombination radiation (light). The transistor established (1947) a basis for the study of the light-emitting diode (LED). The path to an “ultimate lamp,” the p–n diode laser and LED, is described from semiconductor, to energy gap, e–h bipolarity, transistor, the p–n transition, excess carriers, e–h recombination, direct gap $({k}_{e}={k}_{h})$ crystal, autocatalytic e-h/photon interaction, spectral narrowing, stimulated recombination (laser), need for resonator (cavity Q, how?), direct-gap $({k}_{e}={k}_{h})$ III–V alloy, visible spectrum III–V alloy, III–V alloy gap change $(Delta{E}_{g})$ , quantum-well (QW) e–h recombination, stimulated emission solving the problem of photon extraction ( $rightarrow$ 100% quantum efficiency), the p–n diode “ultimate lamp,” return to the 1947 triode, to the transistor, and the base importance informing the realization of a QW-base transistor laser.

Description: Drastic improvements in the crystal quality of GaN enabled the conductivity control of both p- and n-type nitride semiconductors. This led the production of the high-brightness GaN-based p–n junction blue-light-emitting diode (LED) and the high-performance violet/blue laser diode (LD). The development of blue LEDs has allowed us to complete the set of three primary light colors with semiconductors. Coupled with available high-brightness red LEDs, blue/green LEDs are leading to the development of completely solid-state, full-color displays, traffic lights, signage, and specialized lighting applications. White LEDs composed of nitride-based blue/ultraviolet LEDs are more efficient than fluorescent lamps, and, as such, white LEDs are now being used in TVs, cellular phones, and computer displays. Moreover, white LED lamps are heading toward use in general lighting applications in houses, offices, and factories. Blue LEDs, together with available red LEDs, are also being applied as agricultural lighting sources. Nitride-based violet LEDs are being used for reading/writing data in optical disc systems. These nitride-based devices are robust in harsh environments, enable us to save a significant amount of energy, and provide a route to avoid the use of hazardous materials. The use of these devices will be one of our major weapons in the fight against global warming.

Description: Twenty years after Dr. Holonyak's invention, a compact disc (CD) was introduced to the market in 1982. A laser diode is always in the heart of optical storage systems and a variety of other industrial applications. Innovations in laser diode technologies have brought optical storage evolutions from CD to digital versatile disc (DVD) and then Blu-ray disc (BD) every ten years. Since the most important reason for our success in laser development is our choice of metalorganic chemical vapor deposition (MOCVD) for growing these semiconductor alloys, MOCVD equipment, growth conditions, material properties, and phenomena associated with MOCVD and various alloy lasers grown by MOCVD are described in detail. Reviewing the development history would tell us how the laser diode has created a huge market and why recent innovations will predict future applications.

Description: This paper presents the scaled development of a novel point absorber wave energy converter (WEC) developed by Columbia Power Technologies (COLUMBIA POWER, Corvallis, OR, USA), including numerical analysis and scaled wave tank testing. Four hydrodynamic modeling tools are employed to evaluate and optimize the performance of the WEC, including WAMIT, Garrad Hassan's GH WaveDyne, OrcaFlex, and ANSYS AQWA. Performance and mooring estimates at full scale are evaluated and optimized, followed by the development of 1 : 33, 1 : 15, and 1 : 7 scale physical models. The physical tests of the 1 : 33 and 1 : 15 scale WECs were conducted in the wave basins of Oregon State University's O.H. Hinsdale Wave Research Laboratory, in conjunction with the Northwest National Marine Renewable Energy Center (NNMREC). This paper concludes with the development of the 1 : 7 scale WEC and the associated field testing.

Description: The quantum-well (QW) heterojunction bipolar transistor (HBT) laser [the transistor laser (TL)], inherently a fast switching device, operates by transporting small minority base charge densities $sim!! {hbox {10}}^{16} {hbox {cm}}^{-3}$ over nanoscale base thickness ( $〈$ 900 A) in picoseconds. The base QW acts as an optical “collector,” in addition to the usual electrical collector, that selects out “fast” recombining carriers, resulting in a short lifetime ( $sim$ 29 ps) and higher differential laser gains. Charge and current continuity, together with the boundary conditions imposed by both collectors of the TL lead to a new charge control model, “unpinning” of population inversion beyond lasing threshold, quasi-Fermi level discontinuity across base QW, and a new equivalent circuit model requiring an extension to Kirchhoff's law. With the TL, the HBT becomes more than just a charge control device, but also a photon storage and switching device. The TL, owing to fast recombination speed, its unique three-terminal configuration, and the complementary nature of its optical and electrical collector output signals, enables resonance-free base current and collector voltage modulations, and compact realization of electro–optical applications such as nonlinear signal mixing, frequency multiplication, negative feedback, and optoelectronic logic gates.

Description: The discovery of the visible light-emitting diode (LED) 50 years ago by Holonyak and Bevacqua and the associated demonstration of the viability of the III–V semiconductor alloy created a foundational basis for the field of optoelectronics. Key advances which enabled the progression from the first visible LED to today's III–V photonic integrated circuits (PICs) are described. Furthermore, the current state-of-the-art 500-Gb/s and 1-Tb/s large-scale InP transmitter and receiver PICs and their essential role in the optical communications networks are reviewed.

Description: Presents an advertisement for the IEEE Global History Network.

Description: The articles in special issue focus on advancements in very high resolution remote sensing technologies and applications.

Description: The availability of fine spatial resolution earth observation (EO) data has been always considered as a plus for human settlement monitoring from space. It calls, however, for new and efficient data processing tools, capable to manage huge data amounts and provide information for urban area monitoring, management, and protection. Issues related to data processing at the global level imply multiple-scale processing and a focused data interpretation approach, starting from human settlement delineation using spatial information and detailing down to material identification and object characterization using multispectral and/or hyperspectral data sets. This paper attempts to provide a consistent framework for information processing in urban remote sensing, stressing the need for a global approach able to exploit the detailed information available from EO data sets.

Description: With increased use of precision agriculture techniques, information concerning within-field crop yield variability is becoming increasingly important for effective crop management. Despite the commercial availability of yield monitors, many crop harvesters are not equipped with them. Moreover, yield monitor data can only be collected at harvest and used for after-season management. On the other hand, remote sensing imagery obtained during the growing season can be used to generate yield maps for both within-season and after-season management. This paper gives an overview on the use of airborne multispectral and hyperspectral imagery and high-resolution satellite imagery for assessing crop growth and yield variability. The methodologies for image acquisition and processing and for the integration and analysis of image and yield data are discussed. Five application examples are provided to illustrate how airborne multispectral and hyperspectral imagery and high-resolution satellite imagery have been used for mapping crop yield variability. Image processing techniques including vegetation indices, unsupervised classification, correlation and regression analysis, principal component analysis, and supervised and unsupervised linear spectral unmixing are used in these examples. Some of the advantages and limitations on the use of different types of remote sensing imagery and analysis techniques for yield mapping are also discussed.

Description: Recent advances in spectral–spatial classification of hyperspectral images are presented in this paper. Several techniques are investigated for combining both spatial and spectral information. Spatial information is extracted at the object (set of pixels) level rather than at the conventional pixel level. Mathematical morphology is first used to derive the morphological profile of the image, which includes characteristics about the size, orientation, and contrast of the spatial structures present in the image. Then, the morphological neighborhood is defined and used to derive additional features for classification. Classification is performed with support vector machines (SVMs) using the available spectral information and the extracted spatial information. Spatial postprocessing is next investigated to build more homogeneous and spatially consistent thematic maps. To that end, three presegmentation techniques are applied to define regions that are used to regularize the preliminary pixel-wise thematic map. Finally, a multiple-classifier (MC) system is defined to produce relevant markers that are exploited to segment the hyperspectral image with the minimum spanning forest algorithm. Experimental results conducted on three real hyperspectral images with different spatial and spectral resolutions and corresponding to various contexts are presented. They highlight the importance of spectral–spatial strategies for the accurate classification of hyperspectral images and validate the proposed methods.

Description: Hyperspectral imaging is an important technique in remote sensing which is characterized by high spectral resolutions. With the advent of new hyperspectral remote sensing missions and their increased temporal resolutions, the availability and dimensionality of hyperspectral data is continuously increasing. This demands fast processing solutions that can be used to compress and/or interpret hyperspectral data onboard spacecraft imaging platforms in order to reduce downlink connection requirements and perform a more efficient exploitation of hyperspectral data sets in various applications. Over the last few years, reconfigurable hardware solutions such as field-programmable gate arrays (FPGAs) have been consolidated as the standard choice for onboard remote sensing processing due to their smaller size, weight, and power consumption when compared with other high-performance computing systems, as well as to the availability of more FPGAs with increased tolerance to ionizing radiation in space. Although there have been many literature sources on the use of FPGAs in remote sensing in general and in hyperspectral remote sensing in particular, there is no specific reference discussing the state-of-the-art and future trends of applying this flexible and dynamic technology to such missions. In this work, a necessary first step in this direction is taken by providing an extensive review and discussion of the (current and future) capabilities of reconfigurable hardware and FPGAs in the context of hyperspectral remote sensing missions. The review covers both technological aspects of FPGA hardware and implementation issues, providing two specific case studies in which FPGAs are successfully used to improve the compression and interpretation (through spectral unmixing concepts) of remotely sensed hyperspectral data. Based on the two considered case studies, we also highlight the major challenges to be addressed in the near future in this emerging and fast growing research area.

Description: Melt pond statistics (size and shape) have previously been retrieved from aerial photography and high-resolution visible satellite data. These submeter- or meter-resolution visible data can provide reasonably accurate information on melt ponds, but are greatly constrained by the limited solar illumination and frequent cloud cover in the Arctic region. In this study, we venture into exploring high-resolution synthetic aperture radar (SAR) or imaging radar method for melt pond mapping, which is not severely disrupted by cloud or low solar zenith angle. We analyzed high-resolution airborne SAR images (0.3-m resolution) of midsummer sea ice, acquired from a helicopter-borne SAR system in the northern Chukchi Sea. The pond area and shape (circularity) derived from the airborne SAR images showed that the statistics were comparable to those previously observed from aerial photographs. We argue that high-resolution SAR, together with one-to-one comparison with coincident aerial photographs, can be used to map melt ponds at a level of detail comparable to aerial photography or high-resolution optical satellite remote sensing. Our encouraging results suggest the possibility of using high-resolution SAR (current or future systems) to map melt ponds in the Arctic region.

Description: Frequency-domain synthetic aperture radar (SAR) image formation algorithms are of lower computation cost (both in number of elementary operations and in required memory storage) than direct time-domain integration, and do not make the narrowband (monochromatic) assumption. Both advantages are critical to very-high-resolution imaging because a lower complexity yields a drastic computation time decrease as cross-range resolution increases, and the narrowband assumption is more and more a concern as range resolution (hence bandwidth) increases. Though an exact formulation exists ( $omega$ - $k$ algorithm) for a perfect linear uniform acquisition trajectory, in a real-life airborne case, the unavoidable trajectory deviation from a straight line needs to be compensated. This motion compensation (MoComp) operation is much more complicated in the case of frequency-domain processing. An efficient technique for this purpose is presented. This method keeps the parallel processing aspect, and has been programmed both for multithread on multicore/symmetrical multiprocessor central processing units (CPUs) and for graphic processor units (GPUs).

Description: Markov models represent a wide and general family of stochastic models for the temporal and spatial dependence properties associated to 1-D and multidimensional random sequences or random fields. Their applications range over a wide variety of subareas of the information and communication technology (ICT) field, including networking, automation, speech processing, genomic-sequence analysis, or image processing. Focusing on the applicative problem of land-cover mapping from very-high-resolution (VHR) remote sensing images, which is a relevant problem in many applications of environmental monitoring and natural resource exploitation, Markov models convey a great potential, thanks to their capability to effectively describe and incorporate the spatial information associated with image data into an image-classification process. In this framework, the main ideas and previous work about Markov modeling for VHR image classification will be recalled in this paper and processing results obtained through recent methods proposed by the authors will be discussed.

Description: Hyperspectral sensors record the reflectance from the Earth's surface over the full range of solar wavelengths with high spectral resolution. The resulting high-dimensional data contain rich information for a wide range of applications. However, for a specific application, not all the measurements are important and useful. The original feature space may not be the most effective space for representing the data. Feature mining, which includes feature generation, feature selection (FS), and feature extraction (FE), is a critical task for hyperspectral data classification. Significant research effort has focused on this issue since hyperspectral data became available in the late 1980s. The feature mining techniques which have been developed include supervised and unsupervised, parametric and nonparametric, linear and nonlinear methods, which all seek to identify the informative subspace. This paper provides an overview of both conventional and advanced feature reduction methods, with details on a few techniques that are commonly used for analysis of hyperspectral data. A general form that represents several linear and nonlinear FE methods is also presented. Experiments using two widely available hyperspectral data sets are included to illustrate selected FS and FE methods.

Description: Active learning, which has a strong impact on processing data prior to the classification phase, is an active research area within the machine learning community, and is now being extended for remote sensing applications. To be effective, classification must rely on the most informative pixels, while the training set should be as compact as possible. Active learning heuristics provide capability to select unlabeled data that are the “most informative” and to obtain the respective labels, contributing to both goals. Characteristics of remotely sensed image data provide both challenges and opportunities to exploit the potential advantages of active learning. We present an overview of active learning methods, then review the latest techniques proposed to cope with the problem of interactive sampling of training pixels for classification of remotely sensed data with support vector machines (SVMs). We discuss remote sensing specific approaches dealing with multisource and spatially and time-varying data, and provide examples for high-dimensional hyperspectral imagery.

Description: The current increase of spatial as well as spectral resolutions of modern remote sensing sensors represents a real opportunity for many practical applications but also generates important challenges in terms of image processing. In particular, the spatial correlation between pixels and/or the spectral correlation between spectral bands of a given pixel cannot be ignored. The traditional pixel-based representation of images does not facilitate the handling of these correlations. In this paper, we discuss the interest of a particular hierarchical region-based representation of images based on binary partition tree (BPT). This representation approach is very flexible as it can be applied to any type of image. Here both optical and radar images will be discussed. Moreover, once the image representation is computed, it can be used for many different applications. Filtering, segmentation, and classification will be detailed in this paper. In all cases, the interest of the BPT representation over the classical pixel-based representation will be highlighted.

Description: This paper addresses change detection in multitemporal remote sensing images. After a review of the main techniques developed in remote sensing for the analysis of multitemporal data, the attention is focused on the challenging problem of change detection in very-high-resolution (VHR) multispectral images. In this context, we propose a framework that aims at defining a top–down approach to the design of the architecture of novel change-detection systems for multitemporal VHR images. The proposed framework explicitly models the presence of different radiometric changes on the basis of the properties of multitemporal images, extracts the semantic meaning of radiometric changes, identifies changes of interest with strategies designed on the basis of the specific application, and takes advantage of the intrinsic multiscale/multilevel properties of the objects and the high spatial correlation between pixels in a neighborhood. This framework defines guidelines for the development of a new generation of change-detection methods that can properly analyze multitemporal VHR images taking into account the intrinsic complexity associated with these data. In order to illustrate the use of the proposed framework, a real change-detection problem has been considered, which is described by a pair of VHR multispectral images acquired by the QuickBird satellite on the city of Trento, Italy. The proposed framework has been used for defining a system for change detection in the two images. Experimental results confirm the effectiveness of the developed system and the usefulness of the proposed framework.

Description: This paper reflects the polarimetric synthetic aperture radar (POLSAR) data utilization for near-real-time earthquake and/or tsunami damage assessment in urban areas. In order to show the potential of the fully polarimetric high-resolution polarimetric SAR (POLSAR) image data sets, a four-component scattering power decomposition scheme has been developed and applied to monitor near-real-time earthquake and tsunami disaster damages. The test site for natural disaster damages has been selected: parts of the coastal area affected by the March 11, 2011, 9.0 magnitude earthquake that struck off Japan's northeastern coast and triggered a super-tsunami. The color-coded images of the scattering power decomposition scheme are a simple and straightforward tool to interpret the changes over the earthquake/tsunami affected urban areas and man-made infrastructures. This method also holds other types of natural (typhoon or tornado) and man-made disaster assessment applications. It is found that the double-bounce scattering power is the most promising of the input parameters to detect automated disaster affected urban areas at pixel level. It is also observed that the very-high-resolution POLSAR images are required for superior urban area monitoring over the oriented urban blocks with respect to the illumination of radar.

Description: During the last decade, synthetic aperture radar (SAR) became an indispensable source of information in Earth observation. This has been possible mainly due to the current trend toward higher spatial resolution and novel imaging modes. A major driver for this development has been and still is the airborne SAR technology, which is usually ahead of the capabilities of spaceborne sensors by several years. Today's airborne sensors are capable of delivering high-quality SAR data with decimeter resolution and allow the development of novel approaches in data analysis and information extraction from SAR. In this paper, a review about the abilities and needs of today's very high-resolution airborne SAR sensors is given, based on and summarizing the longtime experience of the German Aerospace Center (DLR) with airborne SAR technology and its applications. A description of the specific requirements of high-resolution airborne data processing is presented, followed by an extensive overview of emerging applications of high-resolution SAR. In many cases, information extraction from high-resolution airborne SAR imagery has achieved a mature level, turning SAR technology more and more into an operational tool. Such abilities, which are today mostly limited to airborne SAR, might become typical in the next generation of spaceborne SAR missions.

Description: The classification of high-resolution and fully polarimetric SAR/ISAR data has gained a lot of attention in remote sensing and surveillance problems and is addressed by decomposing the radar target Sinclair matrix. In this paper, the Sinclair matrix has been projected onto the circular polarization basis and is decomposed into five parameters that are invariant to the relative phase $Phi$ , the Faraday rotation $Omega$ , and the target orientation $Psi$ without any information loss. The physical interpretation of these parameters, useful for target classification studies, is found in the wave-particle nature of radar scattering phenomenon given the circular polarization of elemental packets of energy. The proposed deterministic target decomposition is based on the left-orthogonal special unitary SU(2) basis, decomposing the signal backscattered by point targets, represented by the target vector, via six special unitary SU(4) rotation matrices, and by providing full resolution and lossless analysis. Comparisons between the proposed deterministic target decomposition and the Cameron, Kennaugh, Krogager, and Touzi decompositions are also pointed out. Generally, the proposed decomposition provides simpler interpretation, faster parameter extraction, and better generalization properties for the analysis of nonreciprocal or random targets. Several polarimetric SAR/ISAR data sets of UWB data, airborne fully polarimetric EMISAR data, and spaceborne RADARSAT2 are used for illustrating the effectiveness and the usefulness of this decomposition for the classification of point targets. Results are very promising for application use in the next generation of high-resolution spaceborne and airborne Pol-SAR and Pol-ISAR systems.

Description: Smart homes hold the potential for increasing energy efficiency, decreasing costs of energy use, decreasing the carbon footprint by including renewable resources, and transforming the role of the occupant. At the crux of the smart home is an efficient electric energy management system that is enabled by emerging technologies in the electricity grid and consumer electronics. This paper presents a discussion of the state of the art in electricity management in smart homes, the various enabling technologies that will accelerate this concept, and topics around consumer behavior with respect to energy usage.

Description: A home network is one of the next-generation information and communication technology (ICT)-centered applications, and this paper discusses the current state of relating technologies and various aspects necessary for better home network realization. It is necessary to discuss the technologies for a good home network, but it is also important to consider this from the different aspects other than technologies. Cost, power consumption, maintainability, and relevant data volume are such view points, and they support better ecological home network. This paper first discusses the technology components which support realization of a home network. They are network technologies, varieties of devices, software-based systems and standards, and home gateway, the key component of a better home network. Then, the author shows several considerations from the ecological viewpoints such as cost saving, energy saving, human load saving, and data volume saving. The real technology and business for a home network is still in an evolving stage, and it is necessary to discuss the implementation issues for a home network. Home gateway is an important component for managing a home network, and the author proposes a home gateway architecture suitable for better implementation of a home network as a whole.

Description: Discusses the teaching styles of older professors [age 65 years and older] and their younger counterparts in university education.

Description: The articles in this special issue focus on the development and applications supported by smart home technologies.

Description: The Multimedia over Coax Alliance (MoCA) publishes a home networking specification that is the deployed standard for the majority of service providers in North America. It is also being adopted in other parts of the world. MoCA enables highly robust, secure, and low-latency communication at net throughputs of over 400 Mb/s on the home coaxial cable. Its primary use is for the distribution of premium content video, including applications such as multiroom DVR. This paper presents a historical, market, and technical overview of MoCA.

Description: The IEEE 802.1 Audio/Video Bridging Task Group has created a series of IEEE standards that specify methods used to provide the appropriate quality of service (QoS) for audio/video (A/V) streams in a heterogeneous network. This paper describes the requirements for such a network and summarizes the methods described in these standards and how they are used in some example higher layer protocols.

Description: Many researches and standardizations have been done for controlling and managing home networks and appliances during past ten years. Such activities and technologies include the Universal Plug and Play (UPnP)/Digital Living Network Alliance (DLNA), the Energy Conservation and Homecare Network (ECHONET), and the Continua Health Alliance. Such technologies control and manage specific home appliances. However, there have been no technologies and standards for controlling and managing heterogeneous home appliances in a consolidated manner. In addition, there are no standards that fully define technologies for controlling and managing home appliances outside home from mobile phones and cloud servers. In addition to the Internet, new networks such as home networks and sensor networks are emerging. Overlay networking is one of the most suitable technologies for communications among home appliances, home gateways (HGWs), mobile phones, and cloud servers over such heterogeneous networks. Metadata is also an important technology for describing various home appliances in a consistent manner. We have designed overlay networking protocols and metadata for controlling and managing heterogeneous home appliances. Peer-to-Peer Universal Computing Consortium (PUCC) was established to deploy our overlay networking and metadata technologies toward de facto standardization. We explain PUCC overlay networking technologies, and their application to home appliances control from a mobile phone, and describe PUCC activities.

Description: In the last few years, small-cell technology has moved from the realm of academic research to large commercial networks with millions of deployed units. This paper discusses the challenges in deploying and maintaining a large-scale residential small-cell network. The paper first discusses the need for residential small cells to provide ubiquitous coverage in homes located in poor coverage areas of the conventional macrocell, and then describes the architectures of current and next-generation residential small-cell networks, and how these large networks are effectively provisioned and managed. The paper is air interface agnostic and is based on the experience of the authors in commercial deployment of both UMTS and CDMA2000 femtocell networks.

Description: Application of wireless technologies in the smart home is dealt with by pointing out advantages and limitations of available approaches for the solution of heterogeneous and coexisting problems related to the distributed monitoring of the home and the inhabitants. Some hot challenges facing the exploitation of noninvasive wireless devices for user behavior monitoring are then addressed and the application fields of smart power management and elderly people monitoring are chosen as representative cases where the estimation of user activities improves the potential of location-aware services in the smart home. The problem of user localization is considered with great care to minimize the invasiveness of the monitoring system. Wireless architectures are reviewed and discussed as flexible and transparent tools toward the paradigm of a totally automatic/autonomic environment. With respect to available state-of-the-art solutions, our proposed architecture is based also on existing wireless devices and exploits, in an opportunistic way, the characteristics of wireless signals to estimate the presence, the movements, and the behaviors of inhabitants, reducing the system complexity and costs. Selected and representative examples from real implementations are presented to give some insight on state-of-the-art solutions also envisaging possible future trends.

Description: Reports on the development and production of the IBM System/360 system processor which was introduced in 1964. The April 1964 announcement of IBM System/360 was revolutionary in content and unprecedented in scope. It replaced all five of IBM??s (6-b byte) computer product lines with one strictly compatible family, using a new hybrid-integrated-circuit technology and a new 8-b byte architecture. Six processor models offering a 50-fold performance range were accompanied by 54 different peripheral devices, with a pioneering standard interface providing full interchangeability. The software package included communications network capabilities, 16 different language compilers, and a graduated-function, multiprogramming, disk-based operating system.

Description: This paper focuses on how smart technologies integrated in a one-family home, and particularly a window, offer unique challenges and opportunities for designing buildings with the best possible environments for people and nature. Toward an interdisciplinary and multidimensional approach, we address the interaction between daylight defined in technical terms and daylight defined in aesthetic, architectural terms. Through field tests of a Danish carbon-neutral home and an analysis of five key design parameters, we explore the contradictions and potentials in smart buildings, using the smart window as an example of how quality of life and technical advances are synthesized and when they contradict. We focus on the need to define quantitative and qualitative values and synthesize these in a multidimensional design approach, toward allowing the house to adapt to a changing climate, satisfy the human needs of the occupants, together with meeting calculated energy requirements. Thus, integrating windows as key design elements in energy-positive buildings addresses aesthetic as well as technical potentials. This integration of factors from different fields can both support and counterbalance one another in the design process. We maintain that a hybrid approach to the energy design is central. The study illuminates an approach of the design of smart houses as living organisms by connecting technology with the needs of the occupants with the power and beauty of daylight.

Description: Electric vehicles (EVs) are regarded as one of the most effective tools to reduce the oil demands and gas emissions. And they are welcome in the near future for general road transportation. When EVs are connected to the power grid for charging and/or discharging, they become gridable EVs (GEVs). These GEVs will bring a great impact to our society and thus human life. This paper investigates and discusses the opportunities and challenges of GEVs connecting with the grid, namely, the vehicle-to-home (V2H), vehicle-to-vehicle (V2V), and vehicle-to-grid (V2G) technologies. The key is to provide the methodologies, approaches, and foresights for the emerging technologies of V2H, V2V, and V2G.

Description: A century of revolutionary growth in aviation has made global travel a reality of daily life. Aircraft and air transport overcame a number of formidable challenges and hostilities in the physical world. Success in this arduous pursuit was not without leveraging advances of the “cyber” layer, i.e., digital computing, data storage and networking, and software, in hardware, infrastructures, humans, and processes, within the airframe, in space, and on the ground. The physical world, however, is evolving continuously in the 21st century, contributing traffic growth and diversity, fossil fuel and ozone layer depletion, demographics and economy dynamics, as some major factors in aviation performance equations. In the next 100 years, apart from breakthrough physical advances, such as aircraft structural and electrical designs, we envision aviation's progress will depend on conquering cyberspace challenges and adversities, while safely and securely transitioning cyber benefits to the physical world. A tight integration of cyberspace with the physical world streamlines this vision. This paper proposes a novel cyber–physical system (CPS) framework to understand the cyber layer and cyber–physical interactions in aviation, study their impacts, and identify valuable research directions. This paper presents CPS challenges and solutions for aircraft, aviation users, airports, and air traffic management.

Description: Provides a listing of current staff, committee members and society officers.

Description: Advertisement: Members share fascinating first-person stories of technological innovations. Come read and contribute your story.

Description: Provides an overview of the technical articles and features presented in this issue.

Description: In this paper, we survey faster-than-Nyquist (FTN) signaling, an extension of ordinary linear modulation in which the usual data bearing pulses are simply sent faster, and consequently are no longer orthogonal. Far from a disadvantage, this innovation can transmit up to twice the bits as ordinary modulation at the same bit energy, spectrum, and error rate. The method is directly applicable to orthogonal frequency division multiplex (OFDM) and quadrature amplitude modulation (QAM) signaling. Performance results for a number of practical systems are presented. FTN signaling raises a number of basic issues in communication theory and practice. The Shannon capacity of the signals is considerably higher.

Description: Legacy networks, both fixed and mobile, which were originally designed for voice communications, are progressively migrating to new infrastructures that promise to revolutionize the services offered. In this paper, we will cover this new generation of personal communication services, with an emphasis on the family of Internet protocol (IP)-based multimedia subsystem (IMS)-aided infrastructure that relies on the session initiation protocol (SIP). As a benefit, the end users will enjoy a new generation of personal communications services that are accessible anywhere and anytime. These services are directly related to the end users rather than to their diverse devices. It is anticipated that the new deployments of next-generation networks (all-IP based) will accelerate the adoption of the IMS technology.

Description: Discusses the special features, applications, and services provided by identity management-based cognition smartphone technologies.

Description: The articles in this special issue provide a timely and comprehensive review of recent progresses, applications, and challenges spurred by the marine energy generation and transmission technology developments. It is intended for a broad audience interested in gaining comprehensive understanding of technical issues and opportunities that may exist in this important emerging field.

Description: This paper provides an overview of the current state of the technology of offshore wind-based power generation and the technological challenges with emphasis on the electrical parts. First, a brief review of the core control functions, their correlation with operational behavior, and the grid-supporting capability of the machine during normal operation as well as during contingency situations are provided. This is followed by the discussion of basic considerations in wind farm collector design, including topology, grounding options, and outlay of the offshore substation. Then, issues related to offshore turbine foundation and typical dimensions of the offshore substation platform are discussed. The platform is designed to accommodate the main and grounding transformers, the switch gear, and other assorted accessories. Next, options for the transmission link from the offshore plant to the grid onshore are reviewed. Finally, a discussion of issues related to grid integration together with currently applicable special grid code requirements concludes the paper.

Description: The direct-drive wave energy conversion (WEC) system adopts direct-drive power takeoff technique and the linear permanent magnet generate (LPMG) is coupled directly to the floater, which leads to simple configuration and high efficiency. This type of device usually has common features in term of structure, model, optimal control strategy, and power conditioning. Taking the AWS as the example, the models of the direct-drive WEC are first presented, and recommendations are also proposed for their applications. To extract maximum power from the wave, the AWS has to be regulated in resonance with the wave. Different types of control strategy using mechanical and electrical devices have been developed. Their features and applications are compared and discussed. An optimal control strategy, which enables AWS extracting maximum power from the irregular wave, is proposed. Since the floater reciprocates, not only the magnitude but also the direction of the translator motion speed changes. In this condition, the frequency, terminal voltage, and output active power of the LPMG vary. These features may not satisfy the requirements of the grid code for the integration of wave generation into power grid. Hence, the power conditioner is very important for the integration of the AWS into the power grid. The power conditioners are developed to integrate the AWS into the power grid, and the application of the energy storage in smoothing the output power of the AWS is also studied.

Description: Due to its higher capacity factor and proximity to densely populated areas, offshore wind power with integrated energy storage could satisfy $>$ 20% of U.S. electricity demand. Similar results could also be obtained in many parts of the world. The offshore environment can be used for unobtrusive, safe, and economical utility-scale energy storage by taking advantage of the hydrostatic pressure at ocean depths to store energy by pumping water out of concrete spheres and later allowing it to flow back in through a turbine to generate electricity. The storage spheres are an ideal complement to energy harvesting machines, such as floating wind turbines (FWTs). The system could provide near-base-load-quality utility-scale renewable energy and do double duty as the anchoring point for the generation platforms. Analysis indicates that storage can be economically feasible at depths as shallow as 200 m, with cost per megawatt hour of storage dropping until 1500 m before beginning to trend upward. The sweet spot occurs when the concrete wall thickness to withstand the hydrostatic pressure provides enough ballast mass, and this will depend on the strength of used concrete and reinforcement. In addition, the required concrete would use significant amounts of fly ash from coal-fired power plants, and the spheres can serve as artificial reefs.

Description: This paper gives a historical overview of the development of the U.K. marine energy sector from its academic beginnings in the early 1970s. It includes discussion on government support policies and where the sector might develop up to and beyond the end of this decade. The paper also presents two very different projects: the European Marine Energy Centre in Orkney, U.K., and the forthcoming All Waters Current and Wave Test Facility in Edinburgh, U.K., as examples of capital investment in the sector.

Description: There are very ambitious plans in Europe for changing the energy infrastructure in order to reduce greenhouse gas emissions. This involves scenarios where renewable energy sources by 2050 will meet almost 100% of the electric power demand. This has spurred offshore wind farm development activities in the North Sea due to the vast wind energy potential in this region and the potential lack of suitable onshore sites in the future. Large-scale wind farms in the North Sea pose grid integration challenges such as the need for long-distance subsea power transmission and tackling the impact of wind power variation on alternating current (ac) grids. These challenges can be properly managed by the use of meshed high-voltage direct current (HVDC) grids. Three of the regional groups (RGs) in the European Network of Transmission System Operators for Electricity (ENTSO-E), namely Regional Group Great Britain (RG-GB), Regional Group Nordic (RG-N), and Regional Group Continental Europe (RG-CE), surround the North Sea area. A meshed North Sea HVDC interconnection between offshore wind farms and these three asynchronous ac grids can also enable market integration of the otherwise separate regions. This, in turn, results in better utilization of generation and transmission infrastructures, improved security of power supply, and maximized utilization of renewable energy resources. In this paper, a test scenario of a meshed North Sea HVDC grid is studied to demonstrate the potential of such a system for enhancing power supply security of the ac grids. Simulation studies of the test case show that with proper control techniques, a meshed North Sea HVDC grid can mitigate the effect of wind power variation by facilitating exchange of primary and secondary reserves between asynchronous ac grids.

Description: A number of review articles have synthesized current expert opinion regarding interactions of ocean energy generation technologies with environmental parameters and their potential effects and impacts. Fewer articles have documented such interactions, as operational devices and or demonstration sites at which to make such observations are limited. In this paper, we discuss how the perceived risk or impact of ocean renewable energy development on coastal communities (both the human and marine biological communities) is a function not only of actual physical interactions but also depends on the regulatory environment and how potentially impacted coastal resources are valued by stakeholders. In this paper, we review potential environmental effects of ocean energy, identify applicable federal regulations that address potentially affected ecological components, and highlight observations about stakeholder concerns from experiences in Oregon. Understanding the societal lens through which potential environmental effects are viewed is important for developers to move forward as it will be the regulators and local communities who will determine if projects are permitted.

Description: The primary control on the magnitude of the power losses induced by wind turbine wakes in large wind farms is the hub-height wind speed via its link to the turbine thrust coefficient. Hence, at low to moderate wind speeds (between cut-in and rated turbine wind speeds) when the thrust coefficient is high, wake losses are proportionally larger and decrease to be virtually undetectable at wind speeds above rated wind speeds. Wind direction is also critical. Not only does it determine the effective spacing between turbines but also the wind speed distribution is primarily determined by synoptic forcing and typically has a predominant direction from which wind speeds tend to be higher (from southwest for much of the central United States and northern Europe). Two other interlinked variables, turbulence intensity (TI), and atmospheric stability also dictate wake losses. Quantifying, understanding, modeling, and predicting this complex and interdependent system is therefore critical to understanding and modeling wind farm power losses due to wakes, and to optimizing wind farm layout. This paper quantifies the impact of these variables on the power loss due to wakes using data from the large offshore wind farms located at Horns Rev and Nysted in Denmark.

Description: Marine energy, especially tidal current and ocean wave resources, bear immense potential for generating renewable power toward meeting global electricity needs. A number of conversion technologies have been successfully demonstrated worldwide and precommercial/commercial deployments are expected to appear in the near future. While electric power utilities foresee renewable technologies as a viable alternative to fossil fuels, marine energy technologies are generally excluded in their energy planning processes. Lack of technological preparedness and unavailability of device information are two major obstacles in that regard. This article provides an insight on how such novel schemes of power generation can be analyzed under conventional network planning exercises using generic information. The first study focuses on wave power integration along the coasts of Oregon, USA for the year 2019 and analyzes the Northwest electrical network. The second study considers both tidal current and ocean wave resources in South Korea for the years 2017 and 2022. The primary objective of these high-level grid scenario analysis is to identify the practical potential for longer term large-scale wave and/or tidal power generation, particularly focusing on the transmission networks. Steady-state (overloading and voltage deviations/collapses), time-domain (angular stability and dynamic voltage recovery characteristics), and small-signal (eigenvalue) stability analysis are carried out for these systems. Subsequent to establishing a number of study scenarios, N-1 contingencies and various suitable violation criteria are prepared, which are used in identifying the underlying network bottlenecks, especially within the coastal areas. Simplified generic dynamic models of tidal current and ocean wave devices are developed for the time-domain analysis. It is expected that similar studies, once conducted by the interested utilities, will equip them better toward considering marine energy in their- future portfolios. In addition, device manufacturers and project developers will have greater confidence in the emerging marine energy market.

Description: Presents an historial review of the development and history of the motion picture industry. One of the most influential technologies of the past 100 years has been motion pictures. A photographic technique for capturing action became a new medium, a significant part of the economy, and a dominant part of popular culture. A long series of technical advances created the medium and allowed it to grow to express the visions of filmmakers and to provide entertainment for most of the world??s population.

Description: The photo of Harold A. Peterson was published incorrectly as the photo of Harold O. Peterson (ibid, vol. 96, no. 9, Sep 2008, 1551-1554). The correct photo of Harold O. Peterson is shown.

Description: The rapid increase in renewable energy generation from wind has increased concerns about the impacts that wind arrays have on the marine environment and what these impacts mean for society. One method for identifying the impacts of offshore wind farms (OWFs) on human welfare is through the assessment and valuation of ecosystem services. Using an ecosystem services approach, this paper reviews the impacts of OWFs on the ecosystem services delivered by marine environments. During the construction phase, supporting services such as reduced energy capture and nutrient cycling are changed due to the introduction of hard substrate and the reduction in soft sediment habitat at turbine bases. This may lead to changes in all other ecosystem services, both negative and positive. Quantifying these changes, however, is a challenge partly due to data limitations and a lack of clear understanding of the impacts of OWFs on the marine ecosystems. Scientific effort needs to quantitatively explore the impacts of OWFs on ecosystem functionality and the gathering of data that enables the assessment of changes to ecosystem services. Data needed to better quantify and value the impacts of OWFs on ecosystem services are suggested. The development of methods which integrate socioeconomic valuation of ecosystem services into the evaluation of renewable energy devices compliments efforts in assessing the environmental impacts and should enable a holistic assessment of the impact of renewable energy production and greenhouse gas mitigation technologies on the U.K. carbon footprint.

Description: This paper examines the potential to create an energy-independent smart network for an island community utilizing ocean and wind energy. The analysis involves the simulation of an extensive electrification of the heat and transport sectors on the island and the use of renewable energy to maximize the fuel and emission savings. This study involves a full renewable resource assessment for both wind and ocean devices. It also includes the design of a smart-network control algorithm to optimize the timing of electric vehicle charging and heat pump usage to exploit available renewable energy and minimize cost. Results indicate a dramatic reduction in total energy consumption through the electrification of the heat and transport sectors. For the case study system, it is recommended that efficiency measures be adopted prior to the deployment of more advanced demand technologies and that air-source heat pumps be prioritized over electric vehicle deployment due to the nature of energy demand on the island and the capital costs involved.

Description: Provides a listing of current committee members and society officers.

Description: This paper discusses far-field wireless powering for low-power wireless sensors, with applications to sensing in environments where it is difficult or impossible to change batteries and where the exact position of the sensors might not be known. With expected radio-frequency (RF) power densities in the 20–200- $mu$ W/cm $^{2}$ range, and desired small sensor overall size, low-power nondirective wireless powering is appropriate for sensors that transmit data at low duty cycles. The sensor platform is powered through an antenna which receives incident electromagnetic waves in the gigahertz frequency range, couples the energy to a rectifier circuit which charges a storage device (e.g., thin-film battery) through an efficient power management circuit, and the entire platform, including sensors and a low-power wireless transmitter, and is controlled through a low-power microcontroller. For low incident power density levels, codesign of the RF powering and the power management circuits is required for optimal performance. Results for hybrid and monolithic implementations of the power management circuitry are presented with integrated antenna rectifiers operating in the 1.96-GHz cellular and in 2.4-GHz industrial–scientific–medical (ISM) bands.

Description: Beam control and/or beamforming technologies involving phased arrays can be used to enable highly efficient microwave power transmission (MPT) systems. In Japan, several field MPT experiments using a phased array have been conducted over the years. In 1992, a joint collaborative group successfully conducted a fuel-free flight experiment using phased-array technology, which was referred to as the MIcrowave Lifted Airplane eXperiment. In 2008, Kobe University (Kyoto, Japan) and a U.S. research group successfully conducted an MPT experiment using a phased array that resulted in power transmission over a distance of 150 km. Furthermore, Kyoto University proposed and demonstrated a magnetron-based phased array and conducted MPT from an airship to the ground in spring 2009. In FY2010, Kyoto University developed new highly efficient phased arrays for MPT and solar power satellites. This study provides an overview of past and present Japanese MPT experiments using phased-array technologies.

Description: Efficient wireless power transfer across tissue is highly desirable for removing bulky energy storage components. Most existing power transfer systems are conceptually based on coils linked by slowly varying magnetic fields (less than 10 MHz). These systems have many important capabilities, but are poorly suited for tiny, millimeter-scale implants where extreme asymmetry between the source and the receiver results in weak coupling. This paper first surveys the analysis of near-field power transfer and associated strategies to optimize efficiency. It then reviews analytical models that show that significantly higher efficiencies can be obtained in the electromagnetic midfield. The performance limits of such systems are explored through optimization of the source, and a numerical example of a cardiac implant demonstrates that millimeter-sized devices are feasible.