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With the inherent advantages in SOI CMOS technology, minimizing DC and switching floating body effects have enabled high speed digital processors with more than a 25% improvement over bulk silicon CMOS design. Currently, there is a need for a more comprehensive understanding of AC characteristics on SOI CMOS technology for mixed-mode baseband and RF (radio frequency) applications. The objective of this paper is to present a study of unique AC floating body effects and the resultant low-frequency noise overshoot phenomenon in SOI CMOS technology. Further study of their impact on the RF arena will also be discussed.

Multiple input multiple output (MIMO) wireless systems can offer significant diversity and transmit beamforming with receive combining provides a method to achieve this diversity with simple receive processing. The maximum gains in terms of array gain and diversity, however, requires perfect channel knowledge at the transmitter. In the absence of perfect channel knowledge, the channel information can be quantized at the receiver and sent back to the transmitter using a low-rate feedback link. In the case of narrowband channels, considerable work has been done in reducing the feedback information while maintaining bit-error-rate performance close to the case of perfect channel knowledge. This work, however, does not naturally extend to the case of frequency selective channels and leads to an explosion in the feedback overhead. In this paper, orthogonal frequency division multiplexing (OFDM) is considered as a low complexity implementation of MIMO beamforming combining over frequency selective channels. Two broad classes of algorithms are discussed for quantizing channel information - clustering and transform. The clustering algorithms group the subcarriers and choose a common frequency-domain representation of the channel information for each group. Thus the feedback rate depends on the number of groups and not on the number of subcarriers. The transform algorithms quantize the channel information in time-domain where the transform essentially decorrelates the channel information. Both the algorithms provide significant compression of channel information maintaining bit-error-rate performance close to the case of perfect channel knowledge.

Searching for a closed-form exact solution for American put options under the Black-Scholes framework has been a long standing problem in the past; many researchers believe that it is impossible to find such a solution. In this paper, a closed-form exact solution, in the form of a Taylor’s series expansion, of the well-known Black-Scholes 1 equation is presented for the first time. As a result of this analytic solution, the optimal exercise boundary, which is the main difficulty of the problem, is found as an explicit function of the risk-free interest rate, the volatility and the time to expiration.

RANDOM PROCESSES UNDERLYING STRETCHED TIMES AND DIVERGENT TIME SCALES NEAR THE GLASS TRANSITION John. T. Bendler*, John. J. Fontanella*, Michael. F. Shlesinger ** *Physics Department, U.S. Naval Academy, Annapolis, MD 21402-5026 ** Physical Sciences Division, Office of Naval Research, 800 N. Quincy St., Arlington, VA 22217 Abstract A model of relaxation in glassy materials, involving anomalous slow diffusion of defects, is reviewed. The movement of the defects causes a stretched exponential relaxation. If there is an attractive force between defects then as the temperature is lowered, or the pressure increased, the number of mobile defects will decrease. This loss of mobile defects produces a Vogel type law for the singular behavior of the relaxation time scale at a critical temperature. INTRODUCTION It seems obvious and correct that the way to investigate a glass will involve a detailed study of the glassy material. For example, is the glass a tertiary compound, a polymer, or a metallic glass. We note that several important properties of glasses seem to be universal, independent of the specific material composition. We follow an approach of focusing on what type of defects exist, in the glass, and how do they behave. The actual material composition and structure would determine the defect properties. We relate all relaxation phenomena in the glass to the properties of the defects. These properties can depend explicitly on the temperature and pressure. We explore a model where the defect mobility and number determine universal laws. Specifically the stretched exponential relaxation law arises from the defect mobility, and Vogel a type for the singular divergence of a time scale arises from the decrease of the mobile defect population. In this paper we review the mathematical analysis of the defects and do not go into a detailed analysis of experimental data. We will focus on general properties found for many glasses. STRETCHED EXPONENTIAL RELAXATION Experimentally, it has been found that for many glassy materials that relaxation phenomena, including dielectric relaxation, volumetric relaxation, stress relaxation, and magnetization relaxation, all follow a stretched exponential relaxation

In this paper, in order to de-noise a chaotic signal, we compare the time-frequency deconvolution method with the wavelets method. We apply our results on different dynamical systems and show the capability of wavelets' method to reconstruct the attractor of a chaotic time series. Then, we de-noise different data sets in order to re-built their attractor using the wavelets method. The applications concern temperatures and wind fluctuations, electricity spot prices and financial data sets.

We consider a simple pure exchange economy with two assets, one riskless, yielding a constant return on investment, and one risky, paying a stochastic dividend. Trading takes place in discrete time and in each trading period the price of the risky asset is fixed through the market clearing condition. Individual demands are expressed as fractions of traders wealth and depend on traders forecasts about future price movement. Under these assumptions, we derive the stochastic dynamical system that describes the evolution of price and wealth. We study the cases in which one or two agents operate in the market, identifying the possible equilibria and discussing their stability conditions. The main novelty of this paper rests in the abstraction from the precise characterization of agents' beliefs and preferences. In this respect our results generalize several previous contributions in the field. In particular, we show that, irrespectively of agents' behavior, the system can only possess isolated generic equilibria where a single agent dominates the market and continuous manifolds of non-generic equilibria where heterogeneous agents hold finite shares of the aggregate wealth. Moreover, we show that all possible equilibria belong to a one dimensional "Equilibria Market Line". Finally we discuss the role of different parameters for the stability of equilibria and the selection principle governing market dynamics.

The theory of particle transport with branching in a medium randomly varying in time is developed in this paper. We consider an evolution equation for the probability distribution of the number of particles in a multiplying system whose properties jump randomly between two discrete states. A forward type master equation is derived for the probability distributions, and from these, the first two factorial moments are calculated, including the variance. This model can be considered the unification of stochastic methods that were used either for the particle fluctuations in a constant multiplying medium via the master equation technique, or in a fluctuating medium via the Langevin technique. The results obtain show a much richer variety of behaviour than any of the above two methods separately can reconstruct.

In this paper, we presents a comprehensive overview of novel long-period fiber gratings (LPFGs) fabricated by using the high-frequency CO 2 laser pulses technique for low-cost sensing. These LPFGs have not only better fabrication flexibility, better high temperature capability, much lower cost than those fabricated by the UV exposure method due to the use of relatively inexpensive CO 2 lasers and standard telecommunication fibers, but also a number of unique bend, transverse load and torsion characteristics due to the asymmetrical refractive index distribution on the cross-section of the fiber induced by high-frequency CO 2 laser pulses, offering greater potential for multi-parameter measurement.

This is a review paper summarizing the recent reports on low-frequency noise in Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) with high dielectric constant (high-k) gate oxides. Although several such publications have appeared in the literature recently, the only unified theme among them is that the noise in these high-k gate stacks is considerably higher than that observed on conventional SiO 2 gate oxide transistors. In addition, interface- and bulk-dielectric trap-induced correlated carrier number and mobility fluctuations (Unified Model) seem to be the commonly accepted cause of these fluctuations. This report attempts to compile the published data, make comparisons between different high-k dielectrics with respect to 1/f noise characteristics and reach preliminary conclusions. Since there is still room for improvement in processing of high-k materials for MOSFET applications, the review represents merely a slice in time of the progress made, and not meant to be a fundamental, theoretical review.

The presence of thermal noise dictates that an energy barrier is needed to preserve a binary state. Therefore, all electronic devices contain at least one energy barrier to control electron flow. The barrier properties, such as height, length, and shape determine the operating characteristics of electronic devices. Furthermore, changes in the barrier shape require changes in charge density/distribution. Operation of all charge transport devices includes charging/discharging capacitances to change barrier height. In this paper we analyze energy dissipation for several schemes of charging capacitors. A basic assumption of Reversible Computing is that the computing system is completely isolated from the thermal bath, i. e., phonons are not coupled to the motion of the information-bearing particle. An isolated system is a mathematical abstraction never perfectly realized in practice. Coupling of the system to the rest of the world results in thermal noise and errors due to thermal excitations are equivalent to information erasure, and thus computation dissipates energy. Another source of energy dissipation is due to the need of measurement and control. To analyze this side of the problem, the Maxwell's Demon is a useful abstraction. Proposals for adiabatic circuits do not make attempts to isolate the system from the thermal bath, hence the circuits cannot be reversible. We hold that apparent energy savings in models of adiabatic circuits result from neglecting the total energy needed by other parts of the system to implement the circuit. We are not aware of convincing experimental evidences that adiabatic circuits save wall-plug energy.

In this paper, we discuss the theory of entanglement amplifiers. We first describe non-degenerate optical parametric oscillator as an entanglement amplifier and present an input-output calculation for the entanglement of the output fields. We show that two bright output entanglement beams can be produced from this system. We then show that a correlated spontaneous emission laser can be used to implement an entanglement amplifier.

Functional requirements for modern narrow-band and wide-band wireless and lightwave communication systems place stringent demands on speed and noise behavior of circuits and devices used to design them. MOS technology in the nanometer regime continues to be the low-cost high-performance workhorse driving innovations for these applications. In this paper, we trace the developments in the modeling of noise in MOS transistors as the device channel lengths shrink by a factor or a thousand from tens of micrometers to tens of nanometers. The impact of scaling on classical noise mechanisms is explained. Also, generation of new noise sources as a result of scaling are also described. This leads to a better physical understanding of the noise behavior of these devices. Methods of eliminating some of these noise sources by suitable choice of materials and modifications in device structure are explained. Application of this understanding to the practical design and layout of low-noise high-performance circuits is illustrated. As a result, the noise performance of MOS devices has improved by almost an order of magnitude making them an ideal choice for low-noise communication electronics design. Research continues as the channel lengths shrink further.

In optical communications the transportable bandwidth has exceeded Tbps per fiber, as a result of a dense grid of optical channels in the fiber, known as dense wavelength division multiplexing and which does not come without a price. Degradations and interactions due to non-linear and linear effects degrade the signal thus decreasing signal integrity and channel performance. Channel performance is greatly improved with error detecting and correcting codes that detect up to sixteen errors and correct up to eight within a block of information. However, estimation is limited to BER after monitoring many blocks, which takes valuable time particularly when the traffic per channel is huge. As a consequence, there is a need for fast estimation of the signal integrity and channel performance to ensure that the expected performance metrics are maintained. In this paper, we describe a statistical sampling methodology for the estimation of performance parameters such as BER, SNR, and Q-factor in a very short interval and for all-practical purposes in real-time.

Canalization is a form of network robustness found in genetic regulatory networks that results in a reduction of the variation of phenotypic expression relative to the complexity of the genome. Recently, it was discovered that canalization can evolve in a complex network through a self-organization of node (gene) behavior resulting from a competition of a network's nodes that selects for a diversity of behavior [K.E. Bassler, C. Lee, and Y. Lee, Phys. Rev. Lett. 93, 038101 (2004)]. Previously, this "self-organized" mechanism for the evolution of canalization has been studied only in deterministic model systems. This paper considers the effects of stochastic noise in the signals exchanged between nodes on the self-organized evolution of canalization. We find that small levels of stochastic noise increase the amount of canalization produced. At higher levels of noise, the amount of canalization produced levels off and reaches a maximum value, before it reduces at large levels of noise.

Standard macroeconomics, based on a reductionist approach centered on the representative agent, is badly equipped to explain the empirical evidence where heterogeneity and industrial dynamics are the rule. In this paper we show that a simple agent-based model of heterogeneous financially fragile agents is able to replicate a large number of scaling type stylized facts with a remarkable degree of statistical precision.

This paper firstly presents a novel optical sensor technology developed to locate, from above ground, the lateral position of a buried dielectrically sheathed optical cable. Then, optical sensor methods for the distributed sensing and longitudinal positioning of time-varying acoustic disturbances are presented. It is hoped to present results of a novel field-trial capable OTDR based system in the verbal presentation.

The DARPA Dynamic Optical Tags (DOTs) program has as its goal the development of a low cost, small, robust, persistent, low probability of intercept, 2-way tagging, tracking, and locating device that also supports error free data rates in excess of 100 kbps and can be interrogated at ranges up to and beyond 1Km. The program has selected several promising candidates for this device and is in the process of evaluating individually their performance against predetermined milestones to ascertain whether the technology is feasible and the program should continue for further development. In all cases the candidate devices operate as retro-reflecting optical modulators. Upon interrogation by a laser at the correct wavelength and with the correct code, the tags will proceed to modulate the return retro-reflection. While data for the candidate devices are not yet in hand, nevertheless this paper will provide an overview of the nature of the devices under investigation and speculate on how these devices could be employed for both national security applications.

Recently, there has been a significant interest in employing Terahertz (THz) technology, spectroscopy and imaging for standoff detection applications. There are three prime motivations for this interest: (a) THz radiation can detect concealed weapons since many non-metallic, non-polar materials are transparent to THz radiation, (b) target compounds such as explosives, and bio/chemical weapons have characteristic THz spectra that can be used to identify these compounds and (c) THz radiation poses no health risk for scanning of people. This paper will provide an overview of THz standoff detection of explosives and weapons including discussions of effective range, spatial resolution, and other limitations. The THz approach will be compared to alternative detection modalities such as x-ray and millimeter wave imaging. Keywords: Terahertz, imaging, stand-off, explosive, weapon, interferometric, synthetic aperture 1. INTRODUCTION Over the past several years, there has been an increased interest in the potential of terahertz (THz) detection for imaging of concealed weapons, explosives, chemical and biological agents. There are three major factors contributing to this interest: (a) Terahertz radiation is readily transmitted through most non-metallic and non-polar mediums, thus enabling THz systems to "see through" concealing barriers such as packaging, corrugated cardboard, clothing, shoes, bookbags, etc. in order to probe the potentially dangerous materials contained within. (b) Many materials of interest for security applications including explosives, chemical agents, and biological agents have characteristic THz spectra that can be used to fingerprint and thereby identify these concealed materials. For example, many explosives (for example C-4, HMX, RDX, TNT) have characteristic transmission/ reflection spectra in the THz range

The terahertz (1 THz = 10 12 Hz, 3 mm or 33 cm -1 ) region of the electromagnetic spectrum is typically defined in the frequency range 100 GHz to 10 THz, corresponding to a wavelength range of 3 mm to 30 microns. Following the development of coherent sources and detectors in the early eighties, there has been growing interest in the role of terahertz technology in global homeland security. The terahertz region offers a huge expanse of unused bandwidth. The ability of terahertz radiation to probe intermolecular interactions, large amplitude vibrations and rotational modes, in addition to showing polarization sensitivity makes terahertz radiation a unique and diverse region of the electromagnetic spectrum. Terahertz radiation is also able to ‘see through’ common materials, such as clothing, thick smoke and dust, which are often considered as opaque in other regions of the electromagnetic spectrum. This paper reviews the role of terahertz technology in homeland security and associated limitations of this field. Keywords: terahertz, spectroscopy, explosives, biological, chemical, sensing, bacillus anthracis, false alarm rate, sensitivity, specificity

Since the terrible events of 11 Sep 2001 the response to security vulnerabilities has been to throw “Guns, Gates and Guards” at the problem. Three years later and it is clear that, although this may have had a short-term effect, it is unsustainable and unaffordable in the long term. The war on terrorism is going to be fought for a very long time. Defending against terrorism and enhancing the resilience and robustness of society and its processes now requires constant vigilance. Only technology can provide that vigilance at an efficiency that can provide certainty of detection and fast response. A technology led approach, integrating with people and their processes calls for innovation and a new generation of technology that fuses the physical world with the logical world. This approach is measurable in terms of capability and investment, in the way that the previous Newtonian security approach of cause and effect is not. This paper will address this new security environment and the different approach that R&D has to take to ensure that life and Democracy thrive and terrorism is defeated.

This paper describes a passive millimeter-wave image scanner that leverages technologies previously developed for a video-rate passive millimeter-wave camera (PMC) [1, 2]. The imager has a prime focus elliptical frequency scanned antenna operating in the 75-93 GHz millimeter-wave band, a low noise receiver and a vertical beam former that allows the instantaneous capture of 128 pixel (vertical) column images in 1/30th of a second, with 2-3 K sensitivity. Two dimensional images are created by mechanically rotating the antenna, which produces a 128x60 raster image in 2 seconds. By integrating (averaging) images over a longer time period, we have demonstrated a sub-degree temperature resolution. This sensor has proven itself as a low cost tool for studying the potential of W-band passive imaging for various applications.

Precision geo-location (absolute accuracy of 20 cm or less) is required of high-resolution lidar data (1 m or less post spacing) for general surveying needs and high-quality visualization. Current open-loop airborne-hardware pointing-technology supports precision geo-location at short range (less than a few km). Precision geo-location at longer range can be achieved with more complex pointing-hardware but at substantial cost. This paper introduces the concept of multi-look lidar that has the potential for achieving long-range precision geo-location but at substantially reduced cost. In this concept, lidar data are collected at multiple look-angles that are consistent with Position-Dilution-Of-Precision (PDOP) requirements. The data are registered, triangulated, and block-adjusted with a dense set of self-generated control points. An analytic model is presented that shows that the error performance is independent of range. A flight test is described that validates the multi-look-lidar concept. Potential system-implementations are also described that can have minimal impact on hardware or conventional flight operations.

Over the last two decades, researchers investigated various approaches for detection and classification of targets in forward looking infrared (FLIR) imagery using correlation based techniques. In this paper, a novel technique is proposed to recognize and track single as well as multiple identical and/or dissimilar targets in real life FLIR sequences using a combination of extended maximum average correlation height (EMACH) and polynomial distance classifier correlation filter (PDCCF). The EMACH filters are used for the detection stage and PDCCF filter is used for the classification stage for improving the detection and discrimination capability. The EMACH and PDCCF filters are trained a priori using target images with expected size and orientation variations. In the first step, the input scene is correlated with all the detection filters (one for each desired or expected target class) and the resulting correlation outputs are combined. The regions of interest (ROI) are selected from the input scene based on the regions with higher correlation peak values in the combined correlation output. In the second step, PDCCF filter is applied to these ROIs to identify target types and reject clutters/backgrounds based on a distance measure and a threshold. Moving target detection and tracking is accomplished by applying this technique independently to all incoming image frames. Independent tracking of target(s) from one frame to the other allows the system to handle complicated situations such as a target disappearing in few frames and then reappearing in later frames. This method has been found to yield robust performance for challenging FLIR imagery in terms of faster and accurate detection and classification as well as tracking of the targets.

There are many vital issues which are impacting our daily lives and will continue to haunt us as long as we live on this planet of ours. These issues range from food supply availability, drought, coastal zone erosion, volcanoes, hurricanes, terrorism, global warming, earthquakes, water resources, air quality, public health, and agriculture production. Such societal needs are directly linked to our geometric population growth, and abundance of automobiles, industrial emissions, industrial waste and extensive fishing of our oceans and elimination of our ecology. The questions which require serious thoughts, research, coordination, and resources to understand, plan and strike a sensible balance in our daily lives and the above issues are tough to deal with. However, with the advent of remote sensing technologies, tremendous progress has been made in applying space-based and airborne data and products in solving real societal problems. Several of these problems, such as coastal zone erosion, air quality, severe weather, water availability and quality, public health, fires, land slides and others are intricately related; and in the long run can have serious consequences if not properly addressed by scientists, regulatory bodies and policy makers. Although it is a much involved and tangled web to unravel, nevertheless we have an excellent start in understanding some of the phenomena and hopefully can mitigate some of the severe effects by advancing our scientific knowledge. This paper briefly discusses the applications of remote sensing data from Terra, Aqua, and other NASA satellites how to deal with such complex problems; it provides an excellent start.

The eleven universities of the State University System of Florida (SUS-FL) have established a consortium to address the full range of homeland security and domestic preparedness requirements for both Florida and the U.S. The Consortium has established the Florida Homeland Security Institute to provide an effective and efficient mechanism to coordinate, mobilize, combine, and form into teams the diverse, cross-disciplinary expertise, facilities, and established large base of technology development activities within the SUS-FL institutions and their established associates at industrial companies, governmental labs, and other universities. The Florida Consortium and Institute may provide a model for other state university systems for how to combine established resources effectively to address specific homeland security and domestic preparedness needs. This paper describes the Consortium and Institute goals, structure, and operations, with examples of how it has functioned in its brief existence as an effective mechanism for integrating the wide range of university, industry, and government capabilities within the state for addressing homeland security requirements.

There has been considerable interest in the use of the Submillimeter/THz (SMM/THz) spectral region for gas analysis and detection. This has been driven both by the importance of the application and the THz-TDS community. In this paper we will discuss and compare the attributes of an attractive alternative: cw submillimeter spectroscopy. Particular attention will be paid to sensitivity, specificity, and the investigations of harsh environments. A particularly simple system approach, the FAst Scan Submillimeter Spectroscopy Technique (FASSST), will be discussed and a compact and potentially very low cost implementation described. Results will be presented which include the analyses of complex mixtures of gases with absolute specificity.

A biological(bio)-molecular inspired electronic architecture is presented that offers the potential for defining nanoscale sensor platforms with enhanced capabilities for sensing terahertz (THz) frequency bio-signatures. This architecture makes strategic use of integrated biological elements to enable communication and high-level function within densely-packed nanoelectronic systems. In particular, this architecture introduces a new paradigm for establishing hybrid Electro-THz-Optical (ETO) communication channels where the THz-frequency spectral characteristics that are uniquely associated with the embedded bio-molecules are utilized directly. Since the functionality of this architecture is built upon the spectral characteristics of bio-molecules, this immediately allows for defining new methods for enhanced sensing of THz bio-signatures. First, this integrated sensor concept greatly facilitates the collection of THz bio-signatures associated with embedded bio-molecules via interactions with the time-dependent signals propagating through the nanoelectronic circuit. Second, it leads to a new Multi-State Spectral Sensing (MS3) approach where bio-signature information can be collected from multiple metastable state conformations. This paper will also introduce a new class of prototype devices that utilize THz-sensitive bio-molecules to achieve molecular-level sensing and functionality. Here, new simulation results are presented for a class of bio-molecular components that exhibit the prescribed type of ETO characteristics required for realizing integrated sensor platforms. Most noteworthy, this research derives THz spectral bio-signatures for organic molecules that are amenable to photo-induced metastable-state conformations and establishes an initial scientific foundation and design blueprint for an enhanced THz bio-signature sensing capability.

There is a need for ever more effective security screening to detect an increasing variety of threats. Many techniques employing different parts of the electromagnetic spectrum from radio up to X- and gamma-ray are in use. Terahertz radiation, which lies between microwave and infrared, is the last part to be exploited for want, until the last few years, of suitable sources and detectors. Terahertz imaging and spectroscopy has been shown to have the potential to use very low levels of this non-ionising radiation to detect and identify objects hidden under clothing. This paper describes recent work on the development of prototype systems using terahertz to provide new capabilities in people screening - both at security checkpoints and stand-off detection for remote detection of explosives and both metallic and non-metallic weapons.

Electro-Active Paper (EAPap) has been investigated as an attractive EAP material for artificial muscles due to its many advantages such as lightweight, availability, low cost, large displacement output, low actuation voltage and low power consumption. The EAPap is based on cellulose material, and is shown to involve primarily transport of ions in response to an external electric field. Depending on the electrode material, EAPap has shown actuation displacement in the range of 2-4mm, at a few volts. Drawbacks of EAPap actuators include a low force output and a dependence on humidity. To address these limitations, a hybrid EAPap actuator is developed by incorporating an electrode fabricated using single-wall carbon nanotubes (SWNT)/Polyaniline (PANI) with different dopants. SWNT is dispersed in 1-Methy-2-pyrrolidone (NMP), and the resulting solution is used as a solvent for PANI and the various dopants. The SWNT/PANI/NMP solution is then deposited on the EAPap by spin coating. The coated EAPap is dried in a vacuum oven. Raman spectroscopy, X-Ray diffractometry and SEM tests are taken to confirm that the SWNT/PANI/dopant electrode material is successfully prepared by in situ polymerization. The actuation output of the SWNT/PANI/EAPap samples is tested in an environmental chamber in terms of free displacement and blocked force. When the SWNT/PANI/Cl- coated hybrid actuator is excited with 7Vp-p, a maximum displacement of 3.1mm and a maximum power output of 0.29mW are obtained. The hybrid actuator shows an improved actuation force as a result of enhanced stiffness of EAPap.

One year of continuous measurements of visibility, temperature and relative humidity at the Hong Kong International Airport at Chek Lap Kok (CLK) are combined with the concentrations of the respirable suspended particulates (RSP) measured in Tung Chung near the Airport to extract annual and seasonal characteristics of the aerosols. The knowledge of aerosol characteristics obtained is used in the development of inversion methods for aerosol extinction retrieval from Lidar data. In this paper, the details fo aerosol characteristics and retrieved aersosol extinction profiles are presented. This additional data product requires no additional hardware to the existing Lidar, but only additional computational research efforts. The knowledge of spatil aerosol distributions during haze episodes will be valuable to aviation meteorologists at Chek Lap Kok. Long term visibility studies using Lidar of this kind will help our understanding of the air pollution problem in a coastal urban city like Hong Kong.

Asian dust storms are one of the significant events which influence the environment, climate, as well as land and ocean ecology in East Asian, and at least western Pacific. Understanding these dust storms, about their spatial and temporal variabilities and the characteristics of mineral dust aerosols is of first priority. Owing to limited observation facilities and coarse spatial resolution, so far, our knowledge about Asian dust storms is still very limited, in particular mesoscale structure and mineral dust aerosol's optical depth spectra in severe situation when a lot of instruments are ineffective. In present paper, based on surface meteorological observation relatively high spatial and temporal resolution (about 100 km resolution and 1 hr), we investigated the mesoscale variability of spring dust storms with case study and statistical investigation. Also, base on our solar spectral observation over Beijing, the optical depth spectra of mineral dust aerosols are given with case study and statistics. Comparisons are also made with other related observations in eastern Asia. These results will be useful for estimation of atmospheric dust loading and their transport over eastern part of Northern China.

The one of the most important technique of satellite ocean color remote sensing is the radiance measurement accuracy because the water leaving radiance is only about 5% to 10% of the total radiance arrived at sensor at the satellite altitude. It is necessary to guarantee the accuracy of water leaving radiance measurement of about 5%(relative error) to meet the reversed accuracy of ocean color factors (such as chlorophyll suspended material and so on) within relative error about 30 in open sea (Case I water). When sensor has been in the orbit it is important to take orbit calibration to make up some deficits of the pre-launch calibration in the laboratory. Two kinds of data could be used for orbit calibration one is in-situ measurement date so-called in-situ field calibration and another is other satellite data with higher radiance measurement accuracy so called crossing-calibration. China has launched the third spaceship SZ-3 in March 2002. The main remote sensing sensor is the Chinese Moderate Imaging Spectroradiometer (CMODIS) which has total 34 channels (30 channels of 2Onm interval in the spectral range of 0.403-1.O43μm and four infrared channels with 2.15-2.25um, 8.4-8.5um, 10.3-11.3um and 11.5-12.5um. Following SZ-3 China had the first ocean color satellite HY-1A in May of the same year whose main sensor is for ocean color measurement, called as Chinese Ocean Color and Temperature Scanner, COCTS, providing 8 visible and near-infrared channels similar to SeaWiFS. In this paper, first, the methodology and procedure of satellite cross-calibration are discussed in detail, with taking an example of CMODIS. Then the results of this orbit cross-calibrated by American ocean sensor, Sea Wide Field-of-View Sensor (SeaWiFS), for CMODIS and COCTS are presented with comparing the normarization from pre-lunched Lab-calibration and in-situ measurement.

A Mie lidar was used to make observation of Asian dust over Hefei (31.90° N, 117.16° E) in the every spring from 1998 through 2004. This paper presents main features of vertical distribution and temporal variation of Asian dust extinction coefficient at 532 nm wavelength during the seven years. There were two kinds of vertical distributions of Asian dust extinction coefficients. One indicated that the Asian dust particles intruded into the local boundary layer, causing the very thick dust layer with depth of about 3-4 km. The other showed that the Asian dust passed over Hefei area just above the boundary layer. The aerosol extinction coefficients in the elevated dust layer within the middle troposphere from 3 to 6 km were unusual large. Seasonal average aerosol extinction coefficient profiles showed that larger aerosol extinction coefficients from 1 km to 10 km altitude range were observed in the springtime rather than in any other season.

New high-sensitivity solid-state magnetoresistive (MR) sensor technologies offer significant advantages in nondestructive evaluation (NDE) systems. A key advantage of MR sensors is a flat frequency response extending from dc to hundreds of MHz, making them particularly attractive for low-frequency and multi-frequency eddy current detection for deep-flaw detection and depth profiling. MR sensors are mass produced by thin film processing techniques similar to integrated circuit manufacturing, dramatically reducing the cost per sensor. The fabrication process is compatible with silicon circuit technology, allowing integration of sensors with on-chip signal processing. MR sensors can easily be produced in dense arrays for rapid, single-pass scanning of large areas. The small size and low power consumption of these solid-state magnetic sensors enable the assembly of compact arrays of sensors on a variety of substrates as well as on-chip sensor arrays. Arrays have been fabricated with sensor spacing as small as 5 μm. This paper presents a review of the state of the art in MR sensors and applications in NDE. The physical principles, manufacturing process, and performance characteristics of the three main types of MR devices, anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR) and tunneling magnetoresistance (TMR) are discussed. Their performance is compared to other magnetic sensor technologies for NDE applications. Finally, we provide a comprehensive review of the literature on NDE applications of MR sensors.

Luminescent coatings applications have been increased dramatically over the last decade as imaging capacities have advanced. These coatings have been used to monitor surface temperature and air pressure (oxygen sensing) in testing facilities around the world. Through the commercial suppliers of these coatings, custom assembled hardware systems and especially data reduction and analysis software, the use of smart luminescent coatings are starting to find their way in to inspection monitoring and nondestructive evaluation testing. The use of a temperature sensitive paint for example, can be a potential replacement for infrared imaging where IR techniques are limited due to access, reflections and complex geometries. Detection of the luminescent signal can use simple intensity ratio methods with synchronized pulsing systems to capture frequency responses in imaging applications. Time or frequency methods allow signals to be detected in the presence of high background noise that allow measurements that were previously unobtainable. This paper describes general luminescent sensors, detection methods and examples of coatings that are applied over test examples or embedded in materials to measure or monitor the health of a specimen.

With the strong increase of mask complexity and associated price for each new technology node, mask less lithography represents more and more an interesting and complementary alternative for ASIC manufacturing especially in the fields of low volume and leading eadge technology applications. In the semiconductor business where prices and cycle time are constantly pressured, the capability and flexibility of the electron beam direct write offer an effective real cost and cycle time opportunity thanks to its high-resolution capability but also to its ability to print, modify or correct design everywhere in a circuit. This paper highlights application examples where the advantages of this lithography solution are demonstrated for advanced research and development application with the patterning of 45 nm SRAM and for the fast validation of architecture designs. This work confirms that mask less lithography can be transparently placed into production environment, in association with the "golden" optical lithography reference.

Semiconductor process development teams are faced with increasing process and integration complexity while the time between lithographic capability and volume production has remained more or less constant over the last decade. Lithography tools have often gated the volume checkpoint of a new device node on the ITRS roadmap. The processes have to be redeveloped after the tooling capability for the new groundrule is obtained since straight scaling is no longer sufficient. In certain cases the time window that the process development teams have is actually decreasing. In the extreme, some forecasts are showing that by the time the 45nm technology node is scheduled for volume production, the tooling vendors will just begin shipping the tools required for this technology node. To address this time pressure, IBM has implemented a hybrid-lithography strategy that marries the advantages of optical lithography (high throughput) with electron beam direct write lithography (high resolution and alignment capability). This hybrid-lithography scheme allows for the timely development of semiconductor processes for the 32nm node, and beyond. In this paper we will describe how hybrid lithography has enabled early process integration and device learning and how IBM applied e-beam & optical hybrid lithography to create the world's smallest working SRAM cell.

In this paper, we present a new procedure for computing the band structure of semiconductor-based photonic crystals using the spatial finite-difference and temporal differential formulation. Unlike the conventional plane wave expansion (PWE) method where the wavelet expansion and Fourier transform are required; this new scheme only forces the finite-difference to the Maxwell's equation in the spatial domain. When applying the Bloch’s boundary condition to the algorithm for solving the band-diagram, it will result in a system of first-order differential equations in a matrix format. A band mode can be obtained directly by solving the eigen-value and the eigen-vector of this matrix. Numerical examples to demonstrate the accuracy and efficiency of the proposed approach are given.

This paper first gives an overview of state-of-the-art simulation of semiconductor laser devices. The relevant physical models for multi dimensional, electro thermal, and optical simulation as well as an advanced active region model are reviewed. The second part of this work deals with the management of laser simulation projects and the extraction of the relevant data from simulation results. A new tool called PCM Explorer is presented that is suitable for the integration of numerical models in the design and manufacturing process of semiconductor lasers. Both the device performance as well as the process yield can be predicted with the combination of a comprehensive device simulator, some measurement data for calibration purposes, and the statistical process evaluation tool.

We have developed supercritical hydrothermal synthesis method of nanoparticles. In the method, metal salt aqueous solution is mixed with high temperature water to rapidly increase the temperature of the metal salt solution and thus reduce the reactions and crystallizations during the heating up period. By using this method, we succeeded in the continuous and rapid production of nanocrystals. In this paper, we propose a new method to synthesize organic-inorganic fused materials based on the methods of supercritical hydrothermal synthesis. By introducing organic materials in a reaction atmosphere of supercritical hydrothermal synthesis, nanoparticles whose surface was modified with organic materials were synthesized. In supercritical state, water and organic materials form a homogeneous phase, which provides an excellent reaction atmosphere for the organic modification of nanoparticles. Modification with bio-materials including amino acids was also possible. By changing organic modifiers, particle morphology and crystal structure were changed. This organic surface modification provides a various unique characteristics for the nanoparticles: Dispersion of nanoparticles in aqueous solutions, organic solvents or in liquid polymers can be controlled by selecting hydrophilic or hydrophobic modifiers. Polymer-like materials can be formed for the amino acid modified nanoparticles probably by the self-assembly of amino acid.

We have demonstrated high power, linearly polarized output from an all-fiber laser using an integrated polarizing fiber. In this paper, we will detail the design, fabrication and operation of the single polarization fiber as well as the fiber laser experiments.

In this invited paper, we will discuss the use of quantum dots as nonlinear optical elements in fiber laser sources. Furthemore, a review of the fabrication of the first low-loss (< 0.5 dB/cm) ion-exchanged waveguides in a quantum-dot-doped glass will be presented. We will discuss the coupling, propagation, absorption, and scattering losses in these waveguides. The near-field mode profile along with the refractive index profile of these waveguides will be presented. This PbS quantum-dot-doped glass was chosen due to its attractive optical gain and bleaching characteristics at wavelengths throughout the near infrared. This bleaching of the ground-state optical transition has been utilized for passive modelocking of a variety of lasers in the near infrared. In addition, we will discuss some of the potential integrated and fiber optics applications of our quantum-dot-doped waveguides.

This review paper is based on the 2004 UCLA Seminar on Imaging and Informatics (http://www.radnet.ucla.edu/Arrowhead2004/) which is a joint endeavour between the UCLA and the CARS organization, focussing on workflow analysis tools and the digital operating room. Eleven specific presentations of the Arrowhead Seminar have been summarized in this review referring to redesigning perioperative care for a high velocity OR, intraoperative ultrasound process and model, surgical workflow and surgical PACS, an integrated view , interactions in the surgical OR, workflow automation strategies and target applications, visualisation solutions for the operating room, navigating the fifth dimension, and design of digital operating rooms and interventional suites

Heat shock proteins (HSP) are critical components of a complex defense mechanism essential for preserving cell survival under adverse environmental conditions. It is inevitable that hyperthermia will enhance tumor tissue viability, due to HSP expression in regions where temperatures are insufficient to coagulate proteins, and would likely increase the probability of cancer recurrence. Although hyperthermia therapy is commonly used in conjunction with radiotherapy, chemotherapy, and gene therapy to increase therapeutic effectiveness, the efficacy of these therapies can be substantially hindered due to HSP expression when hyperthermia is applied prior to these procedures. Therefore, in planning hyperthermia protocols, prediction of the HSP response of the tumor must be incorporated into the treatment plan to optimize the thermal dose delivery and permit prediction of overall tissue response. In this paper, we present a highly accurate, adaptive, finite element tumor model capable of predicting the HSP expression distribution and tissue damage region based on measured cellular data when hyperthermia protocols are specified. Cubic spline representations of HSP27 and HSP70, and Arrhenius damage models were integrated into the finite element model to enable prediction of the HSP expression and damage distribution in the tissue following laser heating. Application of the model can enable optimized treatment planning by controlling of the tissue response to therapy based on accurate prediction of the HSP expression and cell damage distribution.

Epilepsy is characterized by paroxysmal transient disturbances of the electrical activity of the brain. Symptoms are manifested as impairment of motor, sensory, or psychic function with or without loss of consciousness or convulsive seizures. This paper presents an initial post-operative heat transfer analysis of surgery performed on a 41 year-old man with medically intractable Epilepsy. The surgery involved tumor removal and the resection of adjacent epileptogenic tissue. Electrocorticography was performed before resection. Cold saline was applied to the resulting interictal spike foci resulting in transient, complete cessation of spiking. A transient one dimensional semi-infinite finite element model of the surface of the brain was developed to simulate the surgery. An approximate temperature distribution of the perfused brain was developed by applying the bioheat equation. The model quantifies the surface heat flux reached in achieving seizure cessation to within an order of magnitude. Rat models have previously shown that the brain surface temperature range to rapidly terminate epileptogenic activity is 20-24°C. The developed model predicts that a constant heat flux of approximately -13,000W/m 2 , applied at the surface of the human brain, would achieve a surface temperature in this range in approximately 3 seconds. A parametric study was subsequently performed to characterize the effects of brain metabolism and brain blood perfusion as a function of the determined heat flux. The results of these findings can be used as a first approximation in defining the specifications of a cooling device to suppress seizures in human models.

Piezoelectric semiconductor with heterostructure can be treated as a piezoelectric transducer for the generation of acoustic waves with wavelength less than 10 nm (nano-acoustic waves) by optical technique. This optical piezoelectric transducer has also been utilized for the detection of the nano-acoustic waves (NAW). In this paper, we discuss the generation, detection, and propagation of nano-acoustic waves in piezoelectric semiconductors. We demonstrate that the acoustic frequency of the NAW can be tuned by an optical control technique. Besides, we have also developed an acoustic sensor with THz bandwidth which can be used to study NAW propagation control devices such as nano-phononic bandgap crystal. We demonstrated that the roughness of an interface can be evaluated by the NAW with a resolution less than 1 nm through the acoustic phasefront distortion effect. With the optical piezoelectric transducer, nano-ultrasonics, which is analogous to typical ultrasonics but on the nanometer scale, has been successfully developed.

This paper reports on progress in the VUV spectroscopy of surfaces and nanostructures, as facilitated by twoexperimental innovations. In Scanning Probe Energy Loss Spectroscopy (SPELS) electrons backscattered from the tip-surface junction are detected when an STM tip is operated in field emission mode. Energy loss features in the range 1-300 eV have been observed, corresponding to optical absorption spectra from the IR through to the VUV and X-rayregions. Recent data suggests in addition that SPELS can record local secondary electron emission spectra. SPELSoffers spatial resolution on the 10 nm scale. High Harmonic Generation (HHG) of VUV light provides a complementaryprobe of the excited states of surfaces and nanostructures, offering a temporal resolution of order 100 fs or below. Theutility of the High Harmonic source is demonstrated by an investigation of the visible fluorescence from thin films ofpassivated CdSe nanocrystals, as a function of excitation energy, decay time and temperature, which thus emerge as newscintillators for VUV applications.Keywords : Scanning tunnelling microscopy; Electron energy loss spectroscopy (EELS); High harmonic generation;femtosecond; CdSe; Quantum dots.

Laser-based technologies have played an important role in manufacturing of hard disk drives. The applications include disk texturing, precision bending of the suspension, precision adjust of the shape of the slider carrying the magnetic read/write head and protection against electrostatic discharge (ESD) in the read/write heads. Disk texturing allows one to reduce slider/disk stiction during contact by producing bumps only a few nanometers high and a few microns in diameter at the landing zone of the disk. Laser bending of the suspension allows one to precisely control gram load, the pre-load force with which the slider is pushed towards the disk, as well as the pitch and roll static attitudes of the slider, which strongly influence its flying characteristics. Laser crown adjust helps control slider flatness to within a few nanometers, with high precision and predictability. These technologies allow one to reduce both the mean and the tolerance of slider/disk spacing, thus effectively enabling higher magnetic recording densities. Laser technology helps to protect the sensitive magnetic read head against electrostatic discharge by allowing one to put an electrical short on the head during most of the part's handling, then removing it using a sharply focussed laser beam during final stages of drive assembly. Laser technology, with its ability to process small areas with precision positioning, being contact free and hence largely contamination free and being able reach areas with optical fibers not easily accessible by mechanical means is ideally suited for these manufacturing processes. In this paper we review the physical mechanisms underlying these technologies and possible future applications of lasers in disk drive manufacturing.

Laser micromaching systems are being used in mainstream high-volume semiconductor applications. Two of those processes, via drilling and thin wafer dicing, are discussed in this paper. Via drilling has been proven viable for forming through chip and blind vias. The inherent flexibility of the laser process makes it possible to control via depth, diameter and sidewall slope. As a mask-less process, laser via drilling can be cost affective and highly flexible in its application. Thin wafer dicing reduces the breakage and damage to thin silicon wafers. A new process has been developed that improves the die strength of laser singulated devices beyond that obtained using conventional sawing techniques.

The laser-induced plasma-assisted ablation (LIPAA) process developed by our group, in which a single conventional pulsed laser is only used, makes it possible to perform high-quality and high-speed glass microfabrication. Up to the present, this process has been widely applied for micromachining of various transparent hard and soft materials. In this process, a laser beam is first directed to a glass substrate placed in vacuum or air. The laser beam passes through the substrate since the wavelength of the laser beam must have no absorption by the substrate for the LIPAA process. The transmitted laser beam is absorbed by a solid target (typically a metal), located behind the substrate. The target is then ablated, resulting in plasma generation. Due to the interaction of the laser beam and the laser-induced plasma, significant ablation takes place at the rear surface of the substrate. Recently, we have developed the proto-type LIPAA system using a second harmonic of diode pumped Q-switched Nd:YAG laser for the practical use. In this paper, we will demonstrate micromachining, crack-free marking, color marking and dicing of glass materials. Additionally, selective metallization of glass and polyimide by the LIPAA process followed by metal chemical-plating is investigated. The discussion includes mechanism and practical applications in micro-electronics industry of the LIPAA process.