Search

Copyright: 2016 SPIE. Due to copyright restrictions, the attached PDF file only contains the abstract of the full text item. For access to the full text item, please consult the publisher's website.

In this paper, we present an industrial application of multispectral imaging, for density measurement of colorants in photographic paper. We designed and developed a 9-band LED illumination based multispectral imaging system specifically for this application in collaboration with FUJIFILM Manufacturing Europe B.V., Tilburg, Netherlands. Unlike a densitometer, which is a spot density measurement device, the proposed system enables fast density measurement in a large area of a photo paper. Densities of the four colorants (CMYK) at every surface point in an image are calculated from the spectral reflectance image. Fast density measurements facilitate automatic monitoring of density changes (which is proportional to thickness changes), which helps control the manufacturing process for quality and consistent output. Experimental results confirm the effectiveness of the proposed system.

In this paper, we demonstrate an automatic image analysis for Micro Total Analysis Systems (μTAS) or Lab-on-Paper (LoP). By placing fiducial markers on μTAS, application can crop image and remove bending distortions, also it can perform colorimetric analysis. With previously taken photo of μTAS device with applied reagents, user can determine ie. illness presence by uploading photo into the program. In the paper was prepared μTAS sheet, algorithm for finding fiducial points and software for colorimetric analysis written in Matlab.

There are several paradigms for color generation in reflective displays (e-Paper) including RGBW color filtering or stacked RGB or CMY. Theoretically, the highest white state reflectance and best color gamut are achieved by stacking three layers of pixels. However, stacking 3 layers induces significant optical losses especially at high resolution and typically does not allow for video operation. Therefore RGBW color filtering is currently preferred for higher resolution and single-layer e-Paper, but only provides color at 25% of the area and a maximum theoretical white reflectance of 50%. Presented herein is a new bi-primary color-system that cooperatively displays two complimentary colors inside a single sub-pixel, and therefore doubles the white state reflectance and color gamut for single-layer e-Paper. Also discussed are candidate e-Paper technologies that may be able to adopt the bi-primary color system, including possible advantages and challenges for each technology.

The UK National Quantum Technology Hub in Sensors and Metrology is one of four flagship initiatives in the UK National of Quantum Technology Program. As part of a 20-year vision it translates laboratory demonstrations to deployable practical devices, with game-changing miniaturized components and prototypes that transform the state-of-the-art for quantum sensors and metrology. It brings together experts from the Universities of Birmingham, Glasgow, Nottingham, Southampton, Strathclyde and Sussex, NPL and currently links to over 15 leading international academic institutions and over 70 companies to build the supply chains and routes to market needed to bring 10–1000x improvements in sensing applications. It seeks, and is open to, additional partners for new application development and creates a point of easy open access to the facilities and supply chains that it stimulates or nurtures.

IR monitoring is a basic tool for quality control and predictive maintenance in the paper industry. There are also other possible interests, e.g. measurements of temperature profiles of high speed production lines. The first possibility to use IR for the above mentioned use appears to be applications of glass heat treatment in on line production. At this time there is a lot of interest to be able to measure temperature profiles from a fast moving surface (e.g. in paper machines) with velocities like 10 - 20 m/s. Normal low speed line scanners typically give scanning speed of 50 Hz which in this case means 20 m/s/50 Hz equals 40 cm resolution. The obtained resolution is not normally high enough. To have more accurate vision from the studied surface IR camera line scanning was proposed to be a solution with line scanning frequencies of 8000 Hz which would provide resolution of 20 m/s/8000 Hz equals 0.25 cm between surface points. It is a well-known fact that all undesired frequencies in paper transfer systems disturb the uniform paper drying process which in some cases is the basic reason for low quality coating or even broken paper line. The possibility to detect these drying problems with IR frequency analysis will give a new way to control the paper drying process. With IR analysis it is possible to get information about temperature distributions along the paper track. Using a well established frequency analysis as a tool, the error estimations are obtained. In most cases an open-roll image from paper track is very desirable because there are no existing wide area measurement systems for this purpose. The careful analysis of this new method is given in the manuscript.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This report describes a method for the creation and automatic content verification of low-cost self-verifiable paper documents. The image of an original document is decomposed to symbol templates and their corresponding locations. The resulting data is further compressed and encrypted, and encoded in custom designed high-capacity color barcodes. The original image and barcodes are printed on the same paper to form a self-verifiable authentic document. During content verification, the paper document is scanned to obtain the barcodes and target image. The original image is reconstructed from data extracted from the barcodes, which is then registered with and compared to the target image. The verification is carried out hierarchically from the entire image down to word and symbol levels. For symbol level comparison, multiple types of features and shape matching are utilized in a cascade. The proposed verification method is inexpensive, robust and fast. Evaluation on 216 character tables and 102 real documents achieved greater than 99% alteration detection rate and less than 1% false positives at the word/symbol level.

Wet paper code is a complex model which mainly used in the field of image coding. This paper is based on the wet paper code model and human visual system, and constructs a new wet paper code steganographic method. According to the regional complexity and other characteristics of the host image, the secret bits are adaptively embedded into wavelet coefficients of image subbands with wet paper code. Secret information receivers do not need to know the specific method of secret writing, just do a simple matrix multiplication operation and can extract the secret information, which in many ways to improve the security of the steganographic algorithm. The experiments show that the method has good visual invisibility and resistance of active steganalysis attacks.

Haptic is one of well-considered device which is suitable for demanding virtual reality applications such as medical equipment, mobile devices, the online marketing and so on. Nowadays, many of concepts for haptic devices have been suggested to meet the demand of industries. Cellulose has received much attention as an emerging smart material, named as electro-active paper (EAPap). The EAPap is attractive for mobile haptic devices due to its unique characteristics in terms of low actuation power, suitability for thin devices and transparency. In this paper, we suggest a new concept of haptic actuator with the use of cellulose EAPap. Its performance is evaluated depending on various actuation conditions. As a result, cellulose electrostatic force actuator shows a large output displacement and fast response, which is suitable for mobile haptic devices.

An important print quality attribute of digital printing equipment deals with the absolute position of the printed image relative to the page. Historically, the most precise method of measuring image to paper (IOP) registration is by scanning a printed sheet on a flatbed scanner. These measurements have been limited to sheets smaller than the full capacity of the printer. In addition, the precision of the measurement has been limited by the accuracy of the scanner itself and the measurement of a few (~4) points on the page have limited the information that can be gathered. The new method proposed in this paper measures IOP registration throughout the sheet in a more precise manner. In a similar fashion, the relative position of the image on both the simplex and duplex side of the print can be determined. In addition, the new method helps link the source of registration errors to individual sub-systems. By generating the individual error sources from a printed sheet enables the understanding of the percentage contribution of each sub-system, prioritizes efforts to obtain better IOP performance, finds initial IOP setup errors of a printing engine, compares different technologies affecting IOP registration in sub-systems and potentially acts as a diagnostic tool for individual sub-systems.

Based on the unique characteristic, the paper currency numbers can be put into record and the automatic identification equipment for paper currency numbers is supplied to currency circulation market in order to provide convenience for financial sectors to trace the fiduciary circulation socially and provide effective supervision on paper currency. Simultaneously it is favorable for identifying forged notes, blacklisting the forged notes numbers and solving the major social problems, such as armor cash carrier robbery, money laundering. For the purpose of recognizing the paper currency numbers, a recognition algorithm based on neural network is presented in the paper. Number lines in original paper currency images can be draw out through image processing, such as image de-noising, skew correction, segmentation, and image normalization. According to the different characteristics between digits and letters in serial number, two kinds of classifiers are designed. With the characteristics of associative memory, optimization-compute and rapid convergence, the Discrete Hopfield Neural Network (DHNN) is utilized to recognize the letters; with the characteristics of simple structure, quick learning and global optimum, the Radial-Basis Function Neural Network (RBFNN) is adopted to identify the digits. Then the final recognition results are obtained by combining the two kinds of recognition results in regular sequence. Through the simulation tests, it is confirmed by simulation results that the recognition algorithm of combination of two kinds of recognition methods has such advantages as high recognition rate and faster recognition simultaneously, which is worthy of broad application prospect.

Due to the rise in performance of digital printing, image-based applications are gaining popularity. This creates needs for specifying the quality potential of printers and materials in more detail than before. Both production and end-use standpoints are relevant. This paper gives an overview of an on-going study which has the goal of determining a framework model for the visual quality potential of paper in color image printing. The approach is top-down and it is founded on the concept of a layered network model. The model and its subjective, objective and instrumental measurement layers are discussed. Some preliminary findings are presented. These are based on data from samples obtained by printing natural image contents and simple test fields on a wide range of paper grades by ink-jet in a color managed process. Color profiles were paper specific. Visual mean opinion score data by human observers could be accounted for by two or three dimensions. In the first place these are related to brightness and color brightness. Image content has a marked effect on the dimensions. This underlines the challenges in designing the test images.

In this paper a new method is proposed to control a vision-based robot in large navigation spaces. In this case, visual features observed by an on-board camera can change drastically or even disappear completely between the initial image, as seen at the beginning of a task, and the final image, as seen at the desired position of the robot. These features are therefore not suffcient for controlling the entire motion of the robotic system from beginning to end. This problem requires a more complete definition and representation of the navigation space. This can be achieved by a topological representation, where the environment is directly defined in the sensor space by a data-base of images. In our approach, this data-base is acquired during an offline learning step. An image retrieval method then indexes and matches a request image, given by the camera, to the closest view within the data-base. In this way, an image path is extracted from the database to link the initial and desired images providing enough information to control the robot. The central point of this paper is focused on the closed-loop control law that drives the robot to its desired position using this image path. The method proposed does not require either a global reconstruction or a temporal planning step. Furthermore, the robot is not obliged to converge directly upon each image waypoint but chooses automatically a better trajectory. The visual servoing control law designed uses specific features which ensure that the robot navigates within the visibility path. Experimental simulations are given to show the effectiveness of this method for controlling the motion of a camera in three-dimensional environments (free-flying camera, or camera moving on a plane).

This paper presents the design and development of a safe MEMS based micro electro-thermal igniter for a safe microfuze for military purpose. The proposed device"s architecture is made of: (1) one pyrotechnical micro igniter, (2) one arming function, (3) one disarming function and (3) one sterilization function. The pyrotechnical electro-thermal igniter consists in a resistive element that converts electrical energy into heat to initiate an energetic material. The arming function permits the igniter to be armed, ready to fire, only if the ignition conditions are respected. For that, a short-circuit to the electrical ground is cut and the igniter is connected to the power supply. The igniter can be reset to the safe mode (disarmed state) thanks to the disarming function that reconnects the igniter's electrical pads to the electrical ground. If necessary the igniter can be sterilized meaning that the system's ignition capability is definitively removed. All these functions are based on the use of two electro-thermal micro switches : one ON-OFF and one OFF-ON. Due to the application requirements (the fuze is used once but after a long storage, all components must have a high level of safety and reliability and the power consumption must be minimized), we opted for a new generation of one shot, safe and reliable micro switches. They are based on electro thermal mechanisms and consist in breaking one electrical connection (ON-OFF switch) or micro soldering locally two electrical connections (OFF-ON switch). Both switches have been developed in MEMS technology, characterized and are presented in this paper. A prototype of safe micro igniter with ON-OFF and OFF-ON switches has been also realized and is presented.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents the whole process of building up a high precision, high dynamical MEMS acceleration sensor. The first samples have achieved a resolution of better than 500 ug and a bandwidth of more than 200 Hz. The sensor fabrication technology is shortly covered in the paper. A theoretical model is built from the physical principles of the complete sensor system, consisting of the MEMS sensor, the charge amplifier and the PWM driver for the sensor element. The mathematical modeling also covers problems during startup. A reduced order model of the entire system is used to design a robust control with the Mixed-Sensitivity H-infinity Approach. Since the system has an unstable pole, imposed by the electrostatic field and time delay, caused by A/D-D/A conversation delay and DSP computing time, limitations for the control design are given. The theoretical model might be inaccurate or lacks of completeness, because the parameters for the theoretical model building vary from sample to sample or might be not known. A new identification scheme for open or closed-loop operation is deployed to obtain directly from the samples the parameters of the mechanical system and the voltage dependent gains. The focus of this paper is the complete system development and identification process including practical tests in a DSP TI-TMS320C3000 environment.

In this paper a model for auditory perception is introduced. This model is based on a network of integrate-and-fire and resonate-and-fire neurons and is aimed to control the phonotaxis behavior of a roving robot. The starting point is the model of phonotaxis in Gryllus Bimaculatus: the model consists of four integrate-and-fire neurons and is able of discriminating the calling song of male cricket and orienting the robot towards the sound source. This paper aims to extend the model to include an amplitude-frequency clustering. The proposed spiking network shows different behaviors associated with different characteristics of the input signals (amplitude and frequency). The behavior implemented on the robot is similar to the cricket behavior, where some frequencies are associated with the calling song of male crickets, while other ones indicate the presence of predators. Therefore, the whole model for auditory perception is devoted to control different responses (attractive or repulsive) depending on the input characteristics. The performance of the control system has been evaluated with several experiments carried out on a roving robot.

An automatic recognition system for Paper Currency Numbers was developed in this paper. The paper currency number can be recognized and recorded by this system at the same time of binding. At First, an image of 8 bits grey-scale was acquired by CCD camera, and then some output number clusters can be through process of segmentation by Grey Ridge-Valley algorithm, orientation by projection, and character recognition by structure-analyzing algorithm. Results of experiments demonstrated that the proposed algorithm of gray ridges and valleys can extract feature effectively, the algorithm of distance of traversing number body orientation acute, and this system achieves a high recognition rate and a fast recognition speed. It still reached the practical degree. The system has applied national patent.

A non-supervised clustering based method for classifying paper according to its quality is presented. The method is simple to train, requiring minimal human involvement. The approach is based on Self-Organizing Maps and texture features that discriminate the texture of effectively. Multidimensional texture feature vectors are first extracted from paper images. The dimensionality of the data is then reduced by a Self-Organizing Map (SOM). In dimensionality reduction, the feature data are projected to a two-dimensional space and clustered according to their similarity. The clusters represent different paper qualities and can be labeled according to the quality information of the training samples. After that, it is easy to find the quality class of the inspected paper by checking where a sample is placed in the low-dimensional space. Tests based on images taken in a laboratory environment from four different paper quality classes provided very promising results. Local Binary Pattern (LBP) texture features combined with a SOM-based approach classified the test data almost perfectly: the error percentage was only 0.2% with the multiresolution version of LBP and 1.6% with the regular LBP. The improvement to the previously used texture features in paper inspection is huge: the classification error is reduced over 40 times. In addition to the excellent classification accuracy, the method also offers a self-intuitive user interface and a synthetic view to the inspected data.

This paper introduces tracking control system with visual feedback to a moving object by using the measurement device which we developed. In order to recognize the moving object, we use two method, using cross-shape mark and Orientation Code Matching (OCM). And the measurement device is constructed PID control system with Extended Kalman Filter in order to track to object. Through the several experiments, we verify the percormance of recognition and tracking.

In this paper we present our work analysing electroencephalographic (EEG) signals for the detection of seizure precursors in epilepsy. Volterra-systems and Cellular Nonlinear Networks are considered for a multidimensional signal analysis which is called the feature extraction problem throughout this contribution. Recent results obtained by applying a pattern detection algorithm and a nonlinear prediction of brain electrical activity will be discussed in detail. The aim of this interdisciplinary project is the realization of an implantable seizure warning and preventing system.

This paper discusses the optics content of the UK A level Advancing Physics course. Some of the novel teaching approaches are presented as well as a teaching sequence. Computer animations and lab work will be demonstrated in the main talk.

This paper reports the current status of the DARPA Quantum Network, which became fully operational in BBN's laboratory in October 2003, and has been continuously running in 6 nodes operating through telecommunications fiber between Harvard University, Boston University, and BBN since June 2004. The DARPA Quantum Network is the world's first quantum cryptography network, and perhaps also the first QKD systems providing continuous operation across a metropolitan area. Four more nodes are now being added to bring the total to 10 QKD nodes. This network supports a variety of QKD technologies, including phase-modulated lasers through fiber, entanglement through fiber, and freespace QKD. We provide a basic introduction and rational for this network, discuss the February 2005 status of the various QKD hardware suites and software systems in the network, and describe our operational experience with the DARPA Quantum Network to date. We conclude with a discussion of our ongoing work.

In this paper, we present schedulers that minimize the total transmit power in a multihop wireless network. The focus is on guaranteeing an end-to-end delay bound for a single variable bit rate flow on a multihop fading channel. We first compute an analytical approximation for the transmit power required to send a variable bit rate source over a finite state fading channel. We then use this approximation to derive schedulers that have low complexity and near optimal performance over multihop networks where the fading processes on the multiple hops are independent. Properties of the optimal delay allocation are also studied; in the special case of a Gaussian network, the optimal delay allocation strategy is completely characterized.

Recent advances in electro-optic transmitters for improved transmission performances are presented, with special focus on lithium niobate based devices for extended reach applications.

We present recent results obtained for an optical chaos communications system using optoelectronic devices. These devices are used to improve privacy and security in information transmission. Two kind of chaos based emitters and receivers are described: a semiconductor laser subject to all-optical feedback and operating in a non-linear regime and a semiconductor laser subject to non-linear electro-optical feedback and operating in a linear regime. We show that both configuration give very good synchronization properties and are suitable for message enconding/decoding at bit rates as high as Gbit/s.

A 128(H) x 64(V) x RGB CMOS imager is integrated with region-of-interest selection, RGB-to-HSI transformation, HSI-based pixel segmentation, 36-bins x 12bits HSI histogramming and sum-of-absolute-difference (SAD) template matching. 32 learned color templates are stored and compared to each image. The chip captures the R, G and B images using in-pixel storage before passing the pixel content to a multiplying digital-to-analog converter (DAC) for white balancing. The DAC can also be used to pipe in images for a PC. The color processing uses a biologically inspired color opponent representation and an analog look-up table to determine the Hue (H) of each pixel. Saturation (S) is computed using a loser-take-all circuit. Intensity (I) is given by the sum color components. A histogram of the segments of the image, constructed by counting the number of pixels falling into 36 Hue intervals of 10 degrees, is stored on chip and compared against the histograms of new segments using SAD comparisons. We demonstrate color-based image segmentation and object recognition with this chip. Running at 30fps, it uses 1mW. To our knowledge, this is the first chip that integrates imaging, color segmentation and color-based object recognition at the focal plane.

Data from a recent “first-look” at using Long Wave InfraRed Imaging Polarimetry (LWIR-IP) to detect surface swimmers is presented and discussed. A significant increase in detection SNR over conventional IR imaging techniques was discovered. The physical phenomena that produces the increased SNR is discussed along with data that shows range effects and their degradation on the SNR. Most significantly, a method to classify the detected object using the same dataset is discussed. Augmenting current swimmer detection systems using this technique will likely significantly decrease the false alarm rates of the system, thus saving manpower resources and preserving force readiness.

Ultrahigh resolution OCT using broadband light sources achieves improved axial image resolutions of ~2-3 um compared to standard 10 um resolution OCT used in current commercial instruments. High-speed OCT using Fourier/spectral domain detection enables dramatic increases in imaging speeds. 3D OCT retinal imaging is performed in human subjects using high-speed, ultrahigh resolution OCT, and the concept of an OCT fundus image is introduced. Three-dimensional data and high quality cross-sectional images of retinal pathologies are presented. These results show that 3D OCT may be used to improve coverage of the retina, precision of cross-sectional image registration, quality of cross-sectional images, and visualization of subtle changes in retinal topography. 3D OCT imaging and mapping promise to help elucidate the structural changes associated with retinal disease as well as to improve early diagnosis and monitoring of disease progression and response to treatment.

An IETM is intended to be the functional equivalent of a paper-based Technical Manual (TM), and in most cases a total replacement for paper manual. In this paper, we will describe some of document image understanding technologies applied to the conversion of paper-based TMs to IETMs. Using these advanced technologies allow us to convert paper-based TMs to class 1/2 IETMs. However, these were not sufficient for an automated integrated logistics support system in the ROC Department of Defense. An advanced IETM system is therefore required. Such class 4/5 like IETM system could provide intelligent display of information and other user applications such as diagnostics, intelligent design and manufacturing, or computer-managed training. The author has developed some of the advanced functions, and examples will be shown to demonstrate the new aspect of IETMs.

A novel technique allowing secure transmission/storage of electronic documents in printed form is described. First, given a document to protect, an error resilient "visibly encrypted" version is printed. Later, when the original document is to be recovered, the system scans the "visibly encrypted" document and decrypts it after asking for a secret key. Unfortunately, one faces the problem that when a document is printed and scanned, the rescanned document may look similar to the original, but will be distorted during the process. Therefore, to ensure reliable and high rate transmission over the print-and-scan channel it is essential a judicious theoretical model for characterizing the problem and providing reliable communications schemes. The proposed method is based on Pulse Amplitude Modulation (PAM), using small square-shaped pulses and a Maximum Likelihood (ML) detector that is derived after estimating the distortions introduced by the print-and-scan channel. Furthermore, it is essential to employ synchronization techniques to correctly demodulate the printed pulses. In our case, we use an adaptive scheme that resembles the well-known phase locked loops (PLL's). Finally, we will discuss schemes that can make the bit stream resilient to transmissions errors and how to combine them with cryptographic algorithms in order to produce a secure system.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The paper industry has used IR cameras primarily for troubleshooting, where the most common examples include the examination of the condition of dryer fabrics and dryer cylinders and the analysis of moisture variations in a paper web. Another application extensively using IR thermography is non-destructive testing of composite materials. This paper presents some recently developed laboratory methods using an IR camera to examine paper structure. Specific areas include cockling, moisture content, thermal uniformity, mechanism of failure, and an analysis of the copying process.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A system has been built that embeds arbitrary digital data in an iconic representation of a text image. For encoding, a page image containing text is analyzed for the text regions. A highly reduced image of the page is generated, with an iconic version of the text that encodes an input data stream substituting for the text regions. The data is encoded into modulations of rectangular iconic representations of text words, where the length, height and vertical positioning of rectangles, as well as the spacing between rectangles, can all be independently varied. No correspondence need be maintained between the words in the document and the word icons. Word icons or other marks on each line can be used for identifying, calibrating and justifying iconic text. Decoding proceeds by finding iconic lines and determining the iconic word sizes and locations. Word icons printed with 8x reduction are reliably decoded from 300 ppi binary scans. One application is to present iconified first pages of many documents on a sheet of paper, where the URL of each document is encoded in its icon. Icon scanning and selection then allows retrieval of the full document. Another use is to print an icon on every page of a document, containing meta-information about the document or the specific page, such as the version, revision history, keywords, authorization, or a signed hashing of the full image for authentication.

The polyphase decomposition of a sequence is an useful tool that has been used in multirate signal processingsuch as in the design of computationally efficient decirnators and interpolators, design of analysis/synthesisfilter banks, and development of fast discrete transform algorithms. This paper reviews a recently introducedgeneralization of the polyphase decomposition concept and outlines some of its applications in the simplifica-tion of digital filtering algorithms such as the design and implementation of finite-impulse-response (FIR) digi-tal filters, design of decimators and interpolators, and discrete Fourier transform computations. 1. INTRODUCTION In conventional digital signal processing systems, the sampling rates of signals are exactly the same at the in-put and the output, and at all internal nodes. On the other hand, there are situations where it is more conve-nient to consider digital signal processing systems characterized by unequal sampling rates at various stages inthe system. Some typical applications of such multirate systems include subband coding of signals, transferof data to and from systems with differing sampling rates, interconnection of frequency-division multiplex andtime-division multiplex telecommunication systems, etc. In many of these and other applications, the poly-phase decomposition of a sequence plays an important role. This paper reviews a generalization of the poly-phase decomposition concept and outlines its application in simplifying a number of digital filtering algo-rithms.

This paper will review the needs of prepress proofing, then, point out some limitations of current proofing methods. After this, DuPont's new technology aimed at providing a modular "ink-on-paper" proofing system, will be described first, the concept, then the overall process and components of this system. And finally, the capabilities of this technology will be summarized

This paper discusses the relationship between the sequential hard c-means (SHCM), learning vector quantization (LVQ), and fuzzy c-means (FCM) clustering algorithms. LVQ and SHCM suffer from several major problems. For example, they depend heavily on initialization. If the initial values of the cluster centers are outside the convex hull of the input data, such algorithms, even if they terminate, may not produce meaningful results in terms of prototypes for cluster representation. This is due in part to the fact that they update only the winning prototype for every input vector. We also discuss the impact and interaction of these two families with Kohonen's self-organizing feature mapping (SOFM), which is not a clustering method, but which often lends itself to clustering algorithms. Then we present two generalizations of LVQ that are explicitly designed as clustering algorithms: we refer to these algorithms as generalized LVQ equals GLVQ; and fuzzy LVQ equals FLVQ. Learning rules are derived to optimize an objective function whose goal is to produce 'good clusters'. GLVQ/FLVQ (may) update every node in the clustering net for each input vector. We use Anderson's IRIS data to compare the performance of GLVQ/FLVQ with a standard version of LVQ. Experiments show that the final centroids produced by GLVQ are independent of node initialization and learning coefficients. Neither GLVQ nor FLVQ depends upon a choice for the update neighborhood or learning rate distribution--these are taken care of automatically.

Our innate ability to process and interpret large volumes of poorly defined visual data, in essence to perceive visual information, enables us to function effectively in a continually changing complex world. As knowledge engineers, it would be highly desirable to incorporate such flexibility into artificial systems. Fuzzy logic is a mathematical tool created to help synthesize complex systems and decision processes that must deal with imprecise or ambiguous information. In terms of vision, this ambiguity arises from the meanings attached to the sensor inputs and the rules used to describe the relationship between the various informative visual attributes. Notions that pertain to vision perception such as fuzzy images, fuzzy mathematical operators and fuzzy inference procedures are outlined in this paper.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In general, a decision on any event is made through a sequence of bifurcating selection process. In addition to numerical computation, the binary logic operations of digital electronics may well be used to describe any complicated decision making procedure. In this paper, we show that the single-input-double-output bifurcating principle may be applied to optical information processing. In particular, the massive parallelism and inherent inaccuracy of optics offer a unique representation of human thinking and decision making process. Coherent optical experiments including pattern recognition and dynamic range compression via photorefractive crystals are used to demonstrate the principle of bifurcating optical information processing.

People do pattern recognition differently from current optical computers, but we can learn from them. This is one sense of `personal.'' The other is that I have sacrificed thoroughness and completeness to cut to the heart of what one person (I) believes to be the key current research issues. It is the kind of paper this person likes to read from others

Measurement of small displacements using interferometry and optical microscopy of transparent phase objects are both well established techniques. Somehow missing, however, is the combination of the interferometry's temporal resolution and displacement sensitivity with the resolving power (and hence ability to spatially discriminate) of high numerical aperture optical microscopy. This paper outlines the design of such an instrument as well as the theory of its operation. The details of both are described in Applied Optics, 29, 2383-91 where relevant references can be found.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We describe a two-layer neural network using holographic optical disks as the interconnection weights. Such a system can be used to implement one two-layer with a large number of hidden units, or several two-layer networks with a smaller number of hidden units© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

After a rapid introduction that presents the main reasons for the renewal of interest for photorefractive holographic memories, we first discuss their potentialities and limitations. We then continue by a presentation and analysis of novel techniques that permit considerable facilitation of the memory operation and improve its capabilities. In conclusion, we indicate envisioned applications for photorefractive holographic memories.

The quantitative analysis of human corneal endothelial cell patterns is analyzed with Fourier transform methods. The optical or digital Fourier transform of the pattern of endothelial cell borders is analyzed to yield the average cell area and the coefficient of variation of the average cell area. The more difficult problem of cell shape characterization is still under investigation. The advantage of the Fourier transform analysis is the parallel processing of the optical Fourier transform and the potential development of a hybrid digital-optical device for the rapid analysis of large numbers of endothelial specular photomicrographs

This conference deals with commercial applications of precision manufacturing rather than research for its own sake. It is therefore relevant that we start by examining the pressures on industry. We live in a world of continuing change and this is reflect most forcibly in manufacturing industry where markets and the manufacturing is becoming more global, product lives shorter, and product variety ever greater.

Recent advances in theoretical and experimental research concerned with the feasibility of the gamma-ray laser are reviewed. The discussion covers the principal concepts, pump calibration, giant pumping resonances, and the development of a laser model. A quantitative model based on new data and concepts demonstrates the feasibility of the gamma-ray laser.

Integer versions of subdivision and corner cutting algorithms of NURBS curves are presented. The algorithms are used to render NURBS curves of any degree on a raster device by either computing a polygonal approximation or by turning on pixels that are closest to the curve. Because of the integer arithmetic used, the algorithms are easily cast in hardware.

The goal of the research described in this paper is the design of an intelligent computer vision system to automatically extract information from paper-based maps and answer queries related to spatial features and structure a geographical data. The foundation to such a system is a set. of powerful image analysis algorithms to operate on digitized images of paper-based maps. Efficient algorithms to orient map images, detect symbols, identify and track various types of lines, follow closed contours, compute distances, find shortest paths, etc. have been developed. An intelligent query processor analyzes the queries presented by the user in a predefined syntax, controls the operation of the image processing algorithms, and interacts with the user. The query processor is written in LISP and calls image analysis routines written in FORTRAN. In this paper we describe the image analysis algorithms and present their effectiveness in extracting information from a simplified map image of 2,048 x 2,048 pixels.© (1988) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper we discuss the electrical and physical properties of interconnection structures that impact the per-formance of computer systems. These considerations are illustrated with three examples of such devices found in atypical main -frame. The requirements for the future are then presented. The ability of new technologies, electrical andoptical for satisfying these requirements are discussed. 1. INTRODUCTION The performance of a modern main -frame computer system depends on the speed of the integrated circuits used tocarry out the logic operations and the electrical characteristics of the interconnection structures used to transport signalsbetween these circuits. A basic measure of system performance is cycle time, the time necessary to perform a funda-mental operation. A computer instruction can involve one or more fundamental operations and may take one or morecycles to complete. Interconnection structures can be roughly divided into those that have a large effect on cycle timeand those that do not. For example, multichip modules, onto which logic chips are directly attached, fall into the formercategory since electrical pulses often travel between different chips to complete a logic operation [1]. Depending on theway the logic is partitioned, critical paths might also exist between circuits on different modules. Then the propertiesof the boards to which the modules are connected will also play a significant role in the cycle time. This type of com-puter interconnection scheme is illustrated in figure 1 where it can be observed that one level of commonly used elec-tronic packaging, the single chip module, has been eliminated.

Rotation-invariant pattern recognition is shown to have intrinsic limitations determined by the set of patterns to be recognized and by the specific optical setup. Within these limitations, a general procedure is proposed for the generation of bipolar filters that do not require the sensitive alignment procedures involved in holographic filters and are suitable for superposition synthesis to achieve rotation invariance.

Invited PaperOptical resonators for associative memoryDana Z. AndersonDepartment of Physics, University of Colorado, andJoint Institute for Laboratory AstrophysicsUniversity of Colorado and National Bureau of StandardsBoulder, Colorado 80309 U.S.A.AbstractOne can construct a memory having associative characteristics using optical resonatorswith an internal gain medium. The device operates on the principle that an optical reso-nator employing a holographic grating can have user prescribed eigenmodes. Informationthat is to be recalled is contained in the hologram. Each information entity (e.g. animage of a cat) defines an eigenmode of the resonator. The stored information is accessedby injecting partial information (e.g. an image of the cat's ear) into the resonator. Theappropriate eigenmode is selected through a competitive process in a gain medium placedinside the resonator. With a net gain greater than one, the gain amplifies the field be-longing to the eigenmode that most resembles the injected field; the other eigenmodes aresuppressed via the competition for the gain. One can expect this device to display sever-al intriguing features such as recall transitions and creativity. I will discuss some ofthe general properties of this class of devices and present the results from a series ofexperiments with a simple holographic resonator employing photorefractive gain.IntroductionAs digital serial processing general purpose computers find their limits in speed andcomputational power, computer architects are turning to special purpose interconnectedmulti- processor machines. New device technology will play an essential role in the de-velopment of these new architectures. It seems inevitable that light will play a profoundrole in future generations of sophisticated computers.Optical processors can access the inherent parallel interconnect characteristics of op-tical components without being limited by the essentially two -dimensional topology of thesilicon wafer. There has been a recent upsurge of interest in the kinds of processing inwhich optics should excel. The application I will discuss here is that of associativememory.An associative memory is one in which a body of information is retrieved from storageby a small part of that body. The recall process associates the small amount of informa-tion with the larger whole. One might, for example, have stored in memory images of acat, a dog, and a mouse. One retrieves the image of the cat by entering an image of onlyits ears. I've used images in the example but the stored contents could be data or infor-mation of any type.The attraction of associative memory for computing applications lies in its resiliencyagainst device element failure and its power in certain kinds of problems such as patternrecognition and signal processing. However, the interest in associative memory does notstem only from the computing community. Models for associative memory exhibit many humanmemory -like characteristics. For example, under the right circumstances they can forgetand make mistakes (associate things that were not intended to be associated). Furthermoreas the elements composing the memory structure become decayed or destroyed, the memory be-comes more or less senile, rather than completely inoperative as is usually the case withthe silicon device. Thus interest in this field has been generated by the neurophysiologycommunity as well, where there is a desire to better understand human memory.Associative memory is by no means a new field. Pioneering contributions have been madeby many, in particular by T. Kohonen of the University of Helsinki and by J. Anderson ofBrown University. 1,2 The current surge of interest on the part of the physics and opticscommunities, however, seems to have been stimulated by some recent work by J. Hopfield atCaltech.3 An electrooptic implementation of associative memory based upon Hopfield's workhas been realized by Psaltis and Farhat.4 The concept discussed below represents a con-siderable departure from previous models; it nonetheless should exhibit the behavior ofthe generic associative memory.

E-learning device is widely used in our daily life. However mobile e-learning machine is not satisfied as expected. Most mobile e-learning device is a static learning device, unable to fulfill the requirement of collaboration, long standby time, usage under strong sunlight. To meet these requirements, we developed a learning machine based on electronic paper. This paper will discuss the software consideration of the device. The software is a knowledge navigation system, the navigation system is based on Ontology. Research shows that combine frame Ontology and description logic together can afford a uniform interface to user application.