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A 0.4 meter lightweight telescope has been developed as a prototype for a future 1.4 meter telescope to be implemented at the Naval Prototype Optical Interferometer (NPOI). Using carbon fiber construction for all components, including optics, an order of magnitude reduction in weight is easily obtainable, with the estimated weight of the 1.4 meter telescope being less than 300 pounds. However, lightweight composite materials traditionally offer certain drawbacks, such as different material behavior and vibration characteristics from conventional materials and difficulty in obtaining optical surface quality. This paper describes the characterization of the mechanical properties of the advanced materials used in the construction of these telescopes and includes measurements of the optical figure obtained with carbon fiber construction.

User interfaces are important for process modeling and detection systems. This paper discusses the user interface design and implementation for the innovative Process Query System (PQS). Discussion focuses on the Hidden Markov Model (HMM) editor, model validation, process query types, and result visualization. A log likelihood indicator is used to evaluate and visualize the goodness of model-observation matching. A numerical method to measure the distinguishability between two HMMs is proposed and proved effective. The measurement is performed by estimating misdetection rate using the Monte Carlo simulation method. A visual HMM comparison tool using this method is implemented in the user interface.

ZnO nanorods grown cellulose film is a fascinating inorganic-organic hybrid nanocomposite in terms of synergistic properties with semiconductive functionality of ZnO and renewability and flexibility of cellulose film. This paper reports the fabrication and evaluation of cellulose ZnO hybrid nanocomposite (CEZOHN). ZnO nanorod is well grown on a cellulose film by simple chemical reaction with direct seeding and hydrothermal growing. CEZOHN has unique electric, electro-mechanical and photo-electrical behaviors. The performance of CEZOHN is estimated by measuring induced photocurrent under UV exposure. Mechanism of UV sensing and its possible applications for flexible and wearable UV sensor are addressed.

A Microlens array is a critical component for optimizing display functions. With the increasing usage of display systems in photonic products nowadays, more attention is being paid to the research and development of fabrication technology for microlens arrays. Ultra-precision machining with a fast tool servo (FTS) is one of the leading methodologies for fabrication of high-quality optical microstructural surfaces. FTS is an independently operated positioning device, which provides an indispensable solution for machining optical microstructures with sub-micrometer form accuracy and nanometric surface finish, without the need for any subsequent post processing. The surface quality of an FTS machined surface depends largely on the selection of cutting conditions. However, the achievement of ultra-precision surface finishing depends greatly on the experience and skill of the machine operators. Determination of optimal cutting conditions can stabilize the quality of the fabricated microlens array. In this paper, the effect of cutting conditions such as depth of cut, feed rate, spindle speed and surface speed are investigated; and optimal surface roughness and surface profiles in ultra-precision machining with FTS can be observed.

Laser ablation is extremely well suited for rapid prototyping and proves to be a versatile technique delivering high accuracy dimensioning and repeatability of features in a wide diversity of materials. In this paper, we present laser ablation as a fabrication method for micro machining of arrays consisting of precisely dimensioned U-grooves in dedicated polycarbonate and polymethylmetacrylate plates. The dependency of the performance on various parameters (wavelength, energy density and pulse frequency) is discussed. The fabricated plates are used to hold optical fibres by means of a UV-curable adhesive. Stacking and glueing of the plates allows the assembly of a 2D connector of plastic optical fibres for short distance optical interconnects.

The traditional lithographic approach employed by the semiconductor industry has been to pursue use of advanced prototype optical exposure tools and resists. The benefits of doing so have been: (1) The lithographic process that is used in development more closely resembles the process that will in fact be used to manufacture the chip. (2) The cost of low K1 imaging (phase-masks, off-axis illumination, and surface imaging resist) can be avoided. However with the introduction of 1Gb-dynamic random access memory (DRAM) development, a paradigm shift is being experienced within the optical lithographic community. With 1Gb-DRAMs, the minimum feature size falls irreversibly below the optical wavelength used to image the feature. Such a situation will make low K1 factor imaging unavoidable. With 175 nm groundrules typical for first generation 1G-DRAMs, K1 factors near 0.4 will be common with 0.5 as an upper limit on advanced systems currently in development irrespective of optical wavelength. This paper will cover the selection process, experimental data, and problems encountered in defining and integrating the lithographic process used to support the critical mask levels on 1Gb-DRAM development. Factors considered include: resist, masks, and illuminations via both simulation and experiment. The simulations were conducted with both internal and externally developed software. The experimental data to be reviewed was generated using an experimental 0.6 NA KrF step and scan system provided by Nikon. The resist used is commercially available from the Shipley corporation.

An effective public safety sensor system for heavily-populated applications requires sophisticated and geographically-distributed infrastructures, centralized supervision, and deployment of large-scale security and surveillance networks. Artificial intelligence in sensor systems is a critical design to raise awareness levels, improve the performance of the system and adapt to a changing scenario and environment. In this paper, a highly-distributed, fault-tolerant, and energy-efficient Smart Sensing Surveillance System (S4) is presented to efficiently provide a 24/7 and all weather security operation in crowded environments or restricted areas. Technically, the S4 consists of a number of distributed sensor nodes integrated with specific passive sensors to rapidly collect, process, and disseminate heterogeneous sensor data from near omni-directions. These distributed sensor nodes can cooperatively work to send immediate security information when new objects appear. When the new objects are detected, the S4 will smartly select the available node with a Pan- Tilt- Zoom- (PTZ) Electro-Optics EO/IR camera to track the objects and capture associated imagery. The S4 provides applicable advanced on-board digital image processing capabilities to detect and track the specific objects. The imaging detection operations include unattended object detection, human feature and behavior detection, and configurable alert triggers, etc. Other imaging processes can be updated to meet specific requirements and operations. In the S4, all the sensor nodes are connected with a robust, reconfigurable, LPI/LPD (Low Probability of Intercept/ Low Probability of Detect) wireless mesh network using Ultra-wide band (UWB) RF technology. This UWB RF technology can provide an ad-hoc, secure mesh network and capability to relay network information, communicate and pass situational awareness and messages. The Service Oriented Architecture of S4 enables remote applications to interact with the S4 network and use the specific presentation methods. In addition, the S4 is compliant with Open Geospatial Consortium - Sensor Web Enablement (OGC-SWE) standards to efficiently discover, access, use, and control heterogeneous sensors and their metadata. These S4 capabilities and technologies have great potential for both military and civilian applications, enabling highly effective security support tools for improving surveillance activities in densely crowded environments. The S4 system is directly applicable to solutions for emergency response personnel, law enforcement, and other homeland security missions, as well as in applications requiring the interoperation of sensor networks with handheld or body-worn interface devices.

A methodology capable of quantitatively assessing the quality of hyperspectral data has become increasingly desirable as hyperspectral remote sensing technology migrates into operational systems. The quality of spectral data depends on many factors including collection parameters charactering the sensor and the scene, and the desired spectral products. Therefore, there is a recognized urgent need to understand the phenomenology associated with the collection paramters and how they relate to the quality of the information extracted from the spectral data for different applications. If such relationships can be established, data collection requirements and tasking strategies can then be formulated for these applications. A spectal quality equation with an excellent least-squares fit was established for object/anomaly detection in an earlier work. This paper describes a spectral quality equation established for material identification. This spectral quality equation relates the collection parameters (i.e. spatial resolution, spectral resolution, signal-to-noise ratio, and scene complexity) to the probability of correct identification (Pi) of materials at a given probability of false alarms (Pfa).

This paper presents the first-ever 120×90 element thermoelectric IR focal plane array (FPA) fabricated wiht CMOS technology. The device has a high repsonsivity of 3,900 V/W and a low cost potential. The overall chip size is 14.4 mm × 11.0 mm with a 12.0 mm × 9.0 mm imaging area. The device structure was optimzed for a vacuum-sealed package. Each detector consists of two pairs of p-n polysilicon thermocouples and an NMOS transistor and has external dimensions of 100μm x 100μm and an internal electrical resistance of 90kΩ. The precisely patterned Au-black IR absorbing layer was achieved by both a low-pressure vapor deposition technique and a lift-off technique utilizing a PSG sacrificial layer. These techniques make it possible to obtain a Au-black pattern with the same degree of accuracy as with the CMOS process. The Au-black layer showed high absorpitivty of more than 90 percent to the light source with a wavelength of from 8 to 13μm. This performance is suitable for consumer electronics as well as automotive applications.

A high-capacity, data-hiding algorithm that lets the user restore the original host image after retrieving the hidden data is presented in this paper. The proposed algorithm can be used for watermarking valuable or sensitive images such as original art works or military and medical images. The proposed algorithm is based on a generalized, reversible, integer transform, which calculates the average and pair-wise differences between the elements of a vector extracted from the pixels of the image. The watermark is embedded into a set of carefully selected coefficients by replacing the least significant bit (LSB) of every selected coefficient by a watermark bit. Most of these coefficients are shifted left by one bit before replacing their LSBs. Several conditions are derived and used in selecting the appropriate coefficients to ensure that they remain identifiable after embedding. In addition, the selection of coefficients ensures that the embedding process does not cause any overflow or underflow when the inverse of the transform is computed. To ensure reversibility, the locations of the shifted coefficients and the original LSBs are embedded in the selected coefficients before embedding the desired payload. Simulation results of the algorithm and its performance are also presented and discussed in the paper.

In this paper, a modeling of the hyperspectrometer using a diffraction axicon as a dispersive element was carried out. It was also proved that a point spread function of such optical system remains almost unchanged on the image pattern, when the width is comparable to the PSF of the hyperspectrometer based on conventional diffraction grating.

This paper describes the use of statistical design experimentation to improve the photoresist performance properties of Dynachem's Nova 2070. A full factorial design was employed to investigate the effects of changes in the weight percent of both the minor resin and sensitizer in the total solids and of changes in the major resin's molecular weight on the after-hardbake wall profiles. The effect of the formulation changes on lithographic properties such as process latitude and resolution has also been measured. Scanning electron micrographs (SEMs) were generated to measure wall profile, thermal, and lithographic properties. A SEM measurement technique was then developed to quantify resist thermal stability. From these measurements models were generated to show the effects of the various formulation changes and to make predictions with respect to optimum formulations. Graphs of profile tendencies as a function of formulation changes and hardbake temperature and response surfaces generated from the various models are presented to help illustrate the optimization trends. With respect to lithographic performance, the experimental and model data indicate that the optimum resist formulation within the tested experimental matrix has the following make-up: high major resin molecular weight, low minor resin content, and high sensitizer content. With respect to thermal stability, the data suggests that the optimum resist formulation is the following: high major resin molecular weight, high minor resin content, and low to medium sensitizer content. The lithographic property optimum formula was retested to optimize its performance as a function of process changes according to a quadratic statistical design. Comparative process latitude graphs contrasting the optimum formula to alternative formulas under their respective optimized process conditions are also presented. These studies are collectively analyzed to indicate the direction that future resist formulation changes could be made to further optimize resist performance.

Future products and processes will be impacted by biology and information technology. The developments in molecular and DNA computing may revolutionize the information technology. In this paper, the product and process design challenges are discussed. Evolutionary computation and data mining are two major tools that will cope with these challenges. The basic background of the two tools as well as examples demonstrating their applications in design and manufacturing are discussed.

Nanowires are expected to play an important role in future electronic, optical devices and nanoelectromechanical devices. Measuring the electrical and mechanical properties of nanowires is however a difficult task due to their small dimensions. Here we report the use of an in-situ microscopy technique, which combines transmission electron microscopy (TEM) with scanning probe microscopy (SPM), to investigate the electrical and mechanical properties of metallic and semiconductor nanowires. Additionally, in this paper we describe a novel approach for synthesizing mesoporous silicas with tunable pore diameters, wall thickness and pore spacings that can be used as tempates for the assembly of semiconductor nanowire arrays. Silicon and germanium nanowires, with size monodisperse diameters, can readily be formed within the mesoporous silica matrix using a supercritical fluid inclusion technique. These nano-composite materials display unique optical properties such as intense room temperature ultraviolet and visible photoluminense. The implication of these mesoporous nanowire materials for future electronic and opto-electronic devices is discussed.

Optical trapping and manipulation are based on three types of the force and momentum, in the range of pN, to grab, lift and rotate microparticles due to the light intensity or phase distribution. In the first type, particles are trapped in the highest intensity region of the beam due to optical gradient force for high refractive index particles with respective to its surrounding medium. Secondly, orbital angular momentum (OAM) of a beam can be transferred to a particle due to phase singularity within a beam. Thirdly, spin angular momentum (SAM) can be transferred to the particles due to the circular polarization of the beam. In recent years, microfabricated optical elements have been used to modulate the amplitude and phase of the optical beam to create new generation of optical tweezers with additional manipulation dimensions. In this paper, a review of our recent discoveries of optical trapping and manipulation using micro-beam shaping and micro-optical elements will be presented.

High-speed digital videoendoscopy system is emerging as a new clinical tool for voice assessment. The system can acquire images of the vibrating vocal folds with simultaneous recording of voice data from the patient. The laryngeal image-based analysis has been proven valuable for objective and quantitative assessment of voice kinematics in health and disease, and meanwhile, acoustic analysis of voice data could assist in the study of phonatory characteristics and reveal useful information related to laryngeal pathophysiology. Contrast to the hardware acquisition systems, the development of effective software for handling such massive visual/sound data has lagged behind. In this paper, a software system is designed to process the laryngeal image sequences and perform image-based analyses as well as acoustic analyses. Our software contains following modules: (1) Import and view Module - to read AVI video data and sound data (wave file), edit/compile and save selected data, make image montages using DirectShow technology and display the acoustic waveform using DirectSound technology; (2) Image Process Module – to perform frame-by-frame image segmentation to delineate the glottis, to extract the GAW and bilateral vocal fold displacements; (3) Image Analysis Module – to adopt Nyquist plot displays that involves the Hilbert transform based analysis of GAW, and to provide instantaneous frequency and amplitude distributions; (4) Acoustic Analysis Module – to perform Fast Fourier Transform (FFT) and Spectrogram analyses of the imported sound data, to display the plot of the sound data and provide instantaneous frequency and amplitude distributions and Nyqiust plot and (5) Dual GAW and sound wave display module. Upon rigorous testing of this software using clinical data samples we demonstrate the applications of the software to the study of dynamic characteristics of the glottis, which may correlate with voice quality and health condition.

Free-Space optical communications has been a subject of research interest nearly since the advent of the laser. Space applications have long been the elusive destiny for this technology. This paper discusses some of the flight experiment history dating back to 1965 and the issues which have delayed widespread adoption. The general benefits and some shortcomings of optical communications over RF alternatives are described. Technological status against today's and future requirements is assessed. Various future applications, notably those in Japan and Europe, are discussed.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Commercially available photoresists for 193nm litho technology still suffer of undesired phenomena, which could eventually limit the stability of critical layer processing. Also standard CD-SEM inspection has its impact on the overall litho budget, as the interaction between the primary electron beam and the photoresist locally modifies target dimension. The reduction of this effect can be important to preserve geometrical and also electrical characteristics of the chip, as the local variation of the CD is detectable also after target etching and resist removal. In this paper different strategies to reduce its impact onto production wafers are investigated and compared. By applying a combination of these techniques, CD local modification can be lowered up to 75%.

In this paper, the Markov random field (MRF) clustering method for highly noisy medical image segmentation is presented. In MRF method, the image to be segmented is analyzed in a probabilistic way that establishes image model by a posteriori probability density function with Bayes' theorem, with relation between pixel positions as well as gray-levels involved. The adaptive threshold parameter is determined in the iterative clustering process to achieve global optimal segmentation. The presented method and other segmentation methods in use are tested on simulation images of different noise levels, and the numerical comparison result is presented. It also is applied on the highly noisy positron emission tomography images, in that the diagnostic hypoxia fraction is automatically calculated. The experimental results are acceptable, and show that the presented method is suitable and robust for noisy image segmentation.

There are a number of designs have been used for the rigid line standard calibration system including those which employ the interferometry technique. This paper concerns a simple design utilising a laser interferometry system which can be expected to provide better accuracy. The design is extended to enable the calibration system to automatically correct the orientation of the calibrated item. Error compensation due to unavoidable misalignment is also described.

This paper describes the business scope to which DLP® Products works under with emphasis placed upon some of the technological complications and challenges present when developing an actuator array with the ultimate intention of rendering visual content at high-definition and standard video rates. Additionally, some general thoughts on alternative applications of this spatial light modulation technology are provided.

This paper deals with the improvement of the characteristics of the CO2 lasers used in surgical systems, particularly the design of single mode laser tubes with high output power density per unit length, the active control and monitoring of laser power level and its stability during long periods, the precise control of the irradiation time when the exposure regimes are diversified and the safety measures against uncontrolled irradiation, as well as the design of new beam delivery systems and specialized interfaces between the laser surgical units and the operating theatre.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the perceptually transparent coding of images, we use representation and quantization strategies that exploit properties of human perception to obtain an approximate digital image indistinguishable from the original. This image is then encoded in an error free manner. The resulting coders have better performance than error free coding for a comparable quality. Further, by considering changes to images that do not produce perceptible distortion, we identify image characteristics onerous for the encoder, but perceptually unimportant. Once such characteristic is the typical noise level, often imperceptible, encountered in still images. Thus, we consider adaptive noise removal to improve coder performance, without perceptible degradation of quality. In this paper, several elements contribute to coding efficiency while preserving image quality: adaptive noise removal, additive decomposition of the image with a high activity remainder, coarse quantization of the remainder, progressive representation of the remainder, using bilinear or directional interpolation methods, and efficient encoding of the sparse remainder. The overall coding performance improvement due to noise removal and the use of a progressive code is about 18%, as compared to our previous results for perceptually transparent coders. The compression ratio for a set of nine test images is 3.72 for no perceptible loss of quality.

In this paper we study conoscopic patterns of single crystals of LiNbO 3 congruent (Li/Nb = 0.946) and stoichiometric (Li/Nb = 1) compounds, as well as congruent crystals doped with cations: Mg 2+ (0.86 wt.%), Zn 2+ (0.03, 0.52, 0.62 wt.%), Cu 2 + (0.015 wt.%), B 3+ (0.12 wt.%), Gd 3+ (0.51 wt.%), Y 3+ (0.46 wt.%), Gd 3+ (0.23 wt.%): Mg 2+ (0.75 wt.%), Mg 2+ (0.86 wt.%): Fe 3+ (0.0036 wt.%), Ta 5+ (1.13 wt.%): Mg 2+ (0.011 wt.%), Y 3+ (0.24 wt.%): Mg 2+ (0.63 wt.%). Conoscopic patterns of lithium niobate crystals were recorded at excitation by He-Ne laser (λo = 632.8 nm) and the second harmonic of MLL-100 laser Y:Al garnet (λo = 532 nm, P = 1mW), which does not cause the effect of photorefractive and more powerful radiation of the second harmonic MLL-100 laser Y: Al garnet (λo = 532 nm, P = 90 mW). Irradiation of crystals radiation 632.8 nm and 532 nm (P = 1 mW) photorefractive effect is absent and there is no disclosure of the photoinduced light scattering indicatrix. In this case, conoscopic paintings reflect the state of structural defects in the crystal in the absence of photorefractive effect. When excited by MLL-100 laser radiation on Y:Al garnet (λo = 532 nm, P = 90 mW) in conoscopic patterns appear as its own crystal defects (defined composition and crystal growth conditions), and defects, induced by laser radiation. These crystals characterized by rather a low photorefractive effect. In crystals with a low effect of photorefractive optical distortions associated with the passage of laser light through the crystal is not "smeared" the strong destruction of the laser beam due to photorefractive effect, and confidently observable.

Recently, an investigation of using holographically based techniques for the cuneiform inscription characterization has been reported in several publications. This paper provides an overview of the development of the experimental systems and techniques. Particularly, we describe the main optimization steps as well as the selected correlation results, and the general frame of the future work.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this article we will present work in progress concerning a knowledge-based system for the labeling of the coronary arteries on single projections. The approach is based on a gradual refinement of the interpretation results, starting from the detection of blood vessel center lines, the extraction of bar-like primitives and the connection into blood vessel segments. In this paper we will focus on the final stage which is the labeling of the delineated blood vessel segments. In contrast with most existing approaches which are mainly based on a sequential labeling of the vessels starting from the most important segment, our system uses a constraint satisfaction technique. Mainly, because most anatomical knowledge can be easily formalized as constraints on local attributes such as position, greyvalue, thickness and orientation and as constraints on relations between blood vessel segments such as "left of" or "in same direction". Anatomical models are developed for the Left Coronary Artery in standard RAO and LAO views. In general, only 1-2 interpretations are left, which is an encouraging result if you take into account that for some projections there is a considerable overlap between vessel segments.

The absolute measurement of the surface figure of large, slightly curved specimens with nanometer accuracy is a demanding task and has not yet been satisfactorily solved. Deflectometric methods offer the possibility of measuring specimens of arbitrary large size and arbitrary figure without a reference surface being required. Here the slope is measured and from this the topography is obtained by integration. The method needs a calibrated (multi-) angle measuring tool (e.g. a commercial autocollimator) and well-defined lateral positioning. Recently, two systems have been described that eliminate the influences of scanning guide and other errors by the use of angle differences only (Extended Shear Angle Difference - ESAD). With the first one of these systems, sub-nm uncertainty has already been achieved for optical flats 150 mm in diameter. In this paper we present recent experimental results obtained with the second system and scan lengths up to 88 cm. The contribution of experimental uncertainties to the uncertainty of topography will be discussed. The behavior of ESAD systems with respect to their spatial frequency response will be discussed. It is shown that the uncertainty of the parabolic part (i.e. curvature) of the figure in particular has to be treated separately and dominates the topography. Applications might reach from wafer inspection to straightness stamdards to flat glass production to free-form synchrotron mirror correction.

In the reverse engineering, the dense and disordered point cloud data contain a huge number of redundancy, which inevitably leads to the significant challenges for the tasks of the subsequent data processing. This paper presents a single axis searching arithmetic to obtain the neighborhood information of a point cloud, and then based on all boundary points extracted and reserved, a non-uniform data reduction scheme, according to a specified curvature threshold and the proportion of reserved points in the k-nearest neighbors, is proposed. The experimental result shows that this approach has a strong ability for identifying boundary points, and can directly and effectively reduce the point cloud data, meanwhile keep the original geometric feature.

The aim of the paper is to analyze the fluorescence characteristics of the neritic water on the Romanian Black Sea coast under anthropogenic influences. A fluorescence LIDAR, based on excimer (308 nm) and a dye laser (367, 460 nm) was used in order to map the Dissolved Organic Matter (DOM) and chlorophyll variations in a marine area. Onboard ship campaign was performed during spring time to evidence the algal blooming. Physicochemical parameters of water and chlorophyll concentration were determined also by laboratory measurements of collected samples. The organic compounds and phytoplankton were characterized based on Laser Induced Fluorescence (LIF) and Raman scattering. Highly polluted areas were noted and mapped along the ship trajectory.

The upcoming 45nm and 32nm device generations will continue the familiar industry lithography trends of decreased production K1 factor, reduced focus error tolerances and increased pattern density. As previous experience has shown, small changes in the values of lithographic K1, focus tolerance and pattern density for the process-design space can lead to large required changes in OPC and RET solutions. Therefore, significant improvements in utility and speed are needed for these new device generations. In this paper we highlight significant new functionality and performance capabilities using existing Field-based OPC and RET methods. The use of dense grid calculations in Field-based methods is shown to provide a software platform for robust and fast implementation of new model-based RET techniques such as model-based assist feature placement and tuning. We present the performance and capability increases for model-based RET methods. Additionally, we have studied and present the performance of production 45nm generation field-based OPC and RET software across several different multiple-purpose hardware platforms. Significant improvements in runtime (for approximately the same hardware cost) are observed with new general purpose hardware platforms and with software optimization for this hardware.

This paper first give a comprehensive discussion about the concept of artificial neural network its research methods and the relations with information processing. On the basis of such a discussion, we expound the mathematical similarity of artificial neural network and information processing. Then, the paper presents a new method of image recognition based on invariant features and neural network by using image Zernike transform. The method not only has the invariant properties for rotation, shift and scale of image object, but also has good fault tolerance and robustness. Meanwhile, it is also compared with statistical classifier and invariant moments recognition method.

Nowadays, big-data centers still rely on hard drives. However, there is strong evidence that these surface-storage technologies are approaching fundamental limits that may be difficult to overcome, as ever-smaller bits become less thermally stable and harder to access. An intriguing approach for next generation data-storage is to use light to store information throughout the three-dimensional volume of a material. In this paper, a review of the major achievements of multilayer optical storage by pre-layered scheme from 2003 is presented and the key technique details are discussed. The authors conclude that multilayer optical storage techniques by pre-layered scheme could be the strong candidates for big data center in the years to come.

Reticle systems are considered to be the classical approach in estimating the position of a target in a considered field of view and are widely used in infrared seekers and trackers. This type of seeker is most suitable for tracking airborne targets such as aircrafts and missiles. For simulation of reticle systems a number of different methods can be used. The relationship between the detector signal u(t), the scene radiance in the reticle plane s(x,t) and the reticle transmission r(x,t) can be expressed as: u(t) equals (integral) Ar(x,t) (DOT) s(x,t)dx. By using an image processing system where the reticle pattern as well as the received radiation are described as digitized images of rather high resolution, simulations can easily be performed. The method can be used for simulation of systems with spinning reticles as well as for systems utilizing fixed reticles with off-axis rotation lens or mirror. Any arbitrary reticle pattern can be studied and the pattern can easily be altered. The simulations have been performed by using a TERAGONTM 4200 image processing system. This paper will describe the simulation method and present a number of examples.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In recent years, the Global Positioning System (GPS) techniques have been widely applied to monitor the superficial movements of landslides. The main objective of this paper is to ascertain the application of GPS in landslide prediction practice, taking Baishuihe landslide as an example. The 1260 x 10 4 m 3 Baishuihe landslide (in the Three Gorges Reservoir, China), susceptible to evolve into a soil slide, is studied. This landslide has been periodically monitored since 2003 with GPS and other conventional equipments. Influencing factors have been recognized through the analysis of the GPS monitoring data. Forecasting the failure of the landslides is difficult because of nonlinear time dependency and seasonal effects, which affect the displacements. According to Crosta's method, Voight model is suggested to forecast fictitious failures and to assess alert velocity thresholds using GPS monitoring data. Voight's equation has been expressed in terms of displacement and used to fit the data by nonlinear estimation techniques. Velocity threshold values have been computed and be used for emergency management by assuming these parameters (α , A , t f ) are representative of the mechanical behaviour of the landslide mass approaching failure.

In this paper, we're binding gold nanoparticles (GNPs) and reduced graphene oxide (rGO) by cystamine (Cys). The PEDOT:PSS mix GNPs/Cys/rGO as a hole transport layer of the solar cell. From the experimental result shows the PEDOT:PSS/GNPs/Cys/rGO/ITO film than ITO film have the best transmittance. It's transmittance was decreased for 1.01% at 545 nm wavelength. The sheet resistance of PEDOT:PSS/GNPs/Cys/rGO/ITO was reduce than PEDOT:PSS/ITO, when it was doped with Gold nanoparticles (GNPs) and rGO on ITO glass. The former is than the latter decreased for 1%. For these reasons due to impact by surface doping of composite plasmonic material.

AL/DTA became a major supplier in the field of space cryogenics for the European Space Industry. From MELFI freezer for the International Space Station (ISS) to HERSCHEL and PLANCK satellites for Cosmic Vision, AL/DTA has acquired a large know-how in space cryogenic systems. Convinced by the great interest of Pulse Tube technology for space applications and especially for Earth Observation or Surveillance Tracking, AL/DTA started its first development in mid nineteenths. Then the European Space Agency started to support the development in 2000. Partnerships were launched with CEA/SBT (France) and Thales Cryogenics B.V. (The Netherlands) in order to take the advantage of the competencies and experience of each other. Based on the will to improve important issues such as reliability and mechanical robustness, technology improvements are now available in AL/DTA Pulse Tube coolers. This paper proposes an overview of AL/DTA cryocoolers for space applications following by a detailed description of Pulse Tube Coolers and particularly their integration.

This paper shows the results of a research program funded by Douglas Aircraft Co. (DAC) to enhance the situational awareness of pilots flying large aircraft low to the ground in high-threat environments. Radical display formats are employed in flying the aircraft. These formats relate to the spatial alignment of a pilot to mobile threats, imprecisely located destinations, moving weather, and fixed terrains. Assumed in the program is a survival-enhancing intelligent avionics autopilot, called Adaptive Network for Avionics Research Management (ANARM). Demonstrations can be done on any IBM-compatible personal computer supporting VGA displays. The capability to allow a pilot to modify the situation's pseudo 3-D viewpoint as a function of time appears to be of particular importance.

In inversing Leaf Area Index (LAI) from remotely sensed data, the transformation of the remotely sensed data from one kind of resolution to another has become a significant problem because of the heterogeneity in pixel. In this paper, based on an analysis of the reasons for error appearing in LAI inversion, the spatial heterogeneity in pixel was described by semivariance. The following conclusions were obtained from this study: In the study area, the spatial heterogeneity of reeds is caused by both the random element and the extent of spatial self-correlation. These factors can be described by the parameters of semivariogram, i.e., nugget and sill. In a pure pixel, little variation was found between the 30m and 60m scale, which means that the scaling problem for pure pixels may be ignored. However, while the degree of heterogeneity within a pixel increases, the spatial heterogeneity in the pixel with larger scale may be somewhat hided compared with the pixel with smaller scale. Results also showed that valid spatial self-correlation scale of reeds in the study area is within 360m.

Both the "Earth" coordinates system and "Non Earth" coordinates system are the coordinates systems mostly used in the GIS software nowadays. In the former coordinates system, the earth is treated as a sphere and in the latter one; all the spatial analysis models are based on the Euclidian Plane. The different coordinates system has the different usage: the "Earth" coordinates system is applied to the spatial analysis of large-scale areas and the "Non Earth" coordinates system is applied to local areas. The error will be made if the usage of the systems is exchanged. Through the analysis of typical MapInfo point and line (area) buffer creating examples, the inaccuracy of MapInfo line (area) buffer creating model based on map projection plane has been found. Analyzing and validating its reason, the improving ideas and methods are given out: constituting line (area) buffer creating model by MapInfo point buffer creating model and convex hull creating model; constituting line (area) buffer creating model based on the earth ellipsoid. This paper not only provides an idiographic method for MapInfo users to improve the accuracy and reliability of spatial analysis, but also reminds users not to abuse the buffer analysis tools. On the other hand, this will put forward a good reference for the new version of MapInfo system and other GIS developers.

Third-generation synchrotron radiation sources are currently becoming operational. These powerful x-ray radiation sources will be critical in advancing research in key areas of science, engineering, and medicine. Efficient utilization of these sources requires the development of critical beamline optical components which can withstand their very intense beams without significant distortion. In this paper we will discuss the applications of an innovative, low-cost, castable form of SiC as a monolithic cooled mirror substrate for use on high energy synchrotron beamlines. The superior bulk material properties of SiC--excellent thermal conductivity, a very low coefficient of thermal expansion, excellent specific stiffness and non-reactive with typical coolants--are well known. In addition to the superior bulk material properties, this high purity form of SiC has a number of other desirable characteristics which make it particularly well suited for this application: 1) it can be fabricated with complex, internal cooling channels in a monolithic fashion; 2) it has been demonstrated to provide the excellent surface figures and surface finishes required for x-ray optics applications; and 3) the castable SiC can be manufactures in a very low cost manner, particularly in high volumes. Overall, the innovative SiC mirror substrate discussed promises to offer improved performance, significantly reduced cost, and reduced risk compared to present approaches.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper we analyze a disk-like quantum dot embedded in an engineered two-dimensional (2D) photonic crystal cavity as an artificial atom. In this quantum dot electron and hole form an exciton where photon and electron-hole bound state can interact. Within the engineered electromagnetic vacuum of the PBG material, the exciton can emit and reabsorb a photon. If the exciton energy lies near the photonic band gap edge the exciton level splits into two levels. This is similar to the interaction of field and an atom in a high Q cavity. Here excitonic states are evaluated taking in to account the band mixing for holes. Also energy associated with dressed exction is evaluated.

We propose and develop a field-widened Michelson interferometer (FWMI) system to act as a new type of spectroscopic filter in HSRL application. Due to the field widening characteristic, the FWMI can allow relatively large off-axis incident angle, and can be designed to any desirable wavelength. The theoretical foundations of the FWMI are introduced in this paper, and the developed prototype interferometer is described. It consists of a solid arm made of the glass H-ZF52 with the dimension of 37.876 mm, and an air gap with the length of 20.382 mm. These two interference arms are connected to a cube beam splitter to constitute a Michelson interferometer. Due to the matched dimensions and refractive indices of the two arms, the experimental testing results show that the OPD variation of the developed FWMI is about 0.04 lambda and the RMS is less than 0.008 lambda when the incident angle is as much as 1.5 degree (half angle). The cumulative wavefront distortion caused by the FWMI is less than 0.1 lambda PV value and 0.02 lambda RMS value. To lock the filtering frequency of the FWMI to the laser transmitter, a frequency locking system, which is actually an electro-optic feedback loop, is established. The setup and principle of this frequency locking system are also described in detail. Good locking accuracy of the FWMI about 27MHz is demonstrated through the frequency locking technique. All these results validate the feasibility of this developed FWMI system as a spectroscopic filter of an HSRL.

We propose in this paper an improved correlation based GPR algorithm for a hand-held landmine detector. The previously proposed correlation based detector (CorrDet) generates prediction errors at different frequency bins and sums the prediction errors to generate a statistical quality for detection. The improved CorrDet applies weighting on the prediction errors before they are added to generate the detection value. The purpose of weighting is to emphasize the prediction error values in the frequency bins that are less affected by clutter. The weighting technique is found to be very effective, especially in detecting deep anti-tank mines and small anti-personnel mines. The performance improvement of the proposed algorithm is demonstrated using seven data sets obtained at different sites and soil conditions that contain over 2300 mine targets.

The introduction of chemically amplified (CA) resist technology to thick films, 10 to 100 um in thickness introduced a number of behavior differences not experienced in thinner films to the same magnitudes. Resist image profile deformation, insensitivity to standing waves and the reduction in polymer deblocking temperatures are significantly affected in thick films to a larger extend than in thinner films. The major contributing factors to these differences are discussed in this paper: 1) the influence of photo-acid generator (PAG) structure on its distribution in resist depth on Cu substrates and 2) thermal acid diffusion, influenced by greater amounts of retained solvents in thick films than in thinner films.

In this paper we shall consider the intrinsic complexity of patterns and the extent to which this notion is well defined. Past work in the computer science and artificial intelligence literature on the decomposition of pictures into their basic building blocks is consistent with our motivation, but this paper will look at the simplest description over all possible methods. Thus, the program complexity of Kolmogorov given the domain is mini-mum in finite length such that a Turing Machine can compute functions in finite time. So, the string approach is well used as Kolmogorov process. The Circular Layer Chart for Recognition (CLCR) is created with total number of elements (29,-1)*4, where L is the number of layers counted from innermost cell in even 2.1 number. A sequence of string arrays, called Circular Layer String Arrays (CLSA), are achieved for each layer. In this paper there are twenty layers used for the recognition of human face pictures. The distance between both arrays of corresponding layers of test pattern and sample is calculated. The inner five layers are applied for the normalization of orientation. That is, if any of these inner layers does not match, the arrays of test pattern are rotated one position and tried again until they are rotated one circle. If any array of inner layers does not match through the normalization of orientation, the sample is rejected. Thus it can save much time for matching.

In this paper a method is proposed to provide enhancement of the intelligibilty of speech which has been contaminated by additive noise. The method is based on the assumption that intelligibility enhancement can be achieved by making use of information directly related to speech intelligibility. A structure which provides the means to implement the method is presented and a discussion of some preliminary results obtained with the method is included.

MTI images of thermal discharge from three power plants are analyzed in this paper with the aid of a 3_D hydrodynamic code. The power plants use different methods to dissipate waste heat in the environment: a cooling lake at Comanche Peak, ocean discharge at Pilgrim and cooling canals at Turkey Point. This paper show s that it is possible to reproduce the temperature distributions captured in MTI imagery with accurate code inputs, but the key parameters change from site to site. Wind direction and speed are the most important parameters at Pilgrim, whereas air temperatures are most important at Comanche Peak and Turkey Point. This paper also shows how the combination of high- resolution thermal imagery and hydrodynamic simulation lead to better understanding of the mechanisms by which waste heat is dissipated in the environment.

Mangrove vegetation is widely employed and studied as it is a unique ecosystem which is able to provide plenty of goods and applications to our country. In this paper, high resolution airborne image data obtained the flight mission on Kuala Sepetang Mangrove Forest Reserve, Perak, Malaysia will be used for mangrove species mapping. Supervised classification using the retrieved surface reflectance will be performed to classify the airborne data using Geomatica 2013 software package. The ground truth data will be used to validate the classification accuracy. High correlation of R 2 =0.873 was achieved in this study indicate that high resolution airborne data is reliable and suitable used for mangrove species mapping.

On September 10, 2007 the Optoelectronics Industry Development Association (OIDA) formed the Silicon Photonics Alliance (SPA) Community of Interest (COI) group within the OIDA to focus on market and business cooperation by its members in order to enable silicon photonics product introduction to mainstream markets. This paper discusses recent development in commercialization of silicon photonics based products, the mission of the SPA in supporting commercialization of Silicon Photonics based products, SPA activities and benefits of joining the alliance. Finally contact information for interested parties is provided to assist in joining the alliance.

A research program at The MITRE Corporation was developed to examine all-optical networks. The central element in this all-optical local area network research testbed was an optical crossbar switch employing semiconductor optical amplifiers (SOAs) as the switching and gain elements. One of the initial applications demonstrated on this all-optical testbed was the capability to transmit amplitude modulated (AM) analog signals through this network. The successful implementation of this capability demonstrates that analog imagery, telemetry, radio frequency communications, and sensor information can be distributed over a switched all-optical network. The principal challenge associated with the transmission of AM signals through the all-optical network are the limitations imposed by the SOAs in the switch. These devices exhibit non-linear transfer characteristics, have limited dynamic range, and high noise levels. This paper will describe the techniques developed to demonstrate acceptable video signal transmission performance through the all-optical switched testbed using FM modulation and microwave subcarrier technology.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.