Shape

Recognizing human action from image sequences is an active area of research in computer vision. In this paper, we present a novel method for human action recognition from image sequences in different viewing angles that uses the Cartesian component of optical flow velocity and human body shape feature vector information. We use principal component analysis to reduce the higher dimensional shape feature space into low dimensional shape feature space. We represent each action using a set of multidimensional discrete hidden Markov model and model each action for any viewing direction. We performed experiments of the proposed method by using KU gesture database. Experimental results based on this database of different actions show that our method is robust.

The present approach for thermal management in metallic railgun armatures relies on using the thermal capacity of the armature material to limit the adiabatic temperature rise during launch. In this, the armature is designed so that, as the accelerating current passes through it, the armature heats up to a maximum temperature that is close to the melting point of the armature material. Careful attention to design has to be exercised in regard to local inhomogeneities where current concentrations and associated temperature excursions may occur. Alternatives to this approach are discussed in this paper. These include the possibilities of conductive gaseous cooling and utilization of the latent heat of evaporation of materials contained within the armature. Further work on these concepts is recommended.

Multiple view 3D video reconstruction of actor performance captures a level-of-detail for body and clothing movement which is time-consuming to produce using existing animation tools. In this paper we present a framework for concatenative synthesis from multiple 3D video sequences according to user constraints on movement, position and timing. Multiple 3D video sequences of an actor performing different movements are automatically constructed into a surface motion graph which represents the possible transitions with similar shape and motion between sequences without unnatural movement artefacts. Shape similarity over an adaptive temporal window is used to identify transitions between 3D video sequences. Novel 3D video sequences are synthesized by finding the optimal path in the surface motion graph between user specified key-frames for control of movement, location and timing. The optimal path which satisfies the user constraints whilst minimizing the total transition cost between 3D video sequences is found using integer linear programming. Results demonstrate that this framework allows flexible production of novel 3D video sequences which preserve the detailed dynamics of the captured movement for actress with loose clothing and long hair without visible artefacts.

One of the major problems an Computer Visaon zs to build systems with the abilily of detecting shapes in arbitrary "real World" images. The target application of our work is the correct adentzfication of road trafic signs in images taken by a car mounted camera. The baszc technique used in this kind of situation is to compare each portzon of an zmage with a set of known models. The approach taken an our work as to zmplement this comparison with Cellular Neural Networks, making it possable to eficaently use a massively parallel architecture. In order to reduce the response time of the system, our approach also ancludes data reduction techniques. The results of several tests, an dzfferent conditions, are reported in the paper. The system correctly detects a test shape in almost all the experiment performed. The paper also contains a detailed description of the system archatecture and of the processzng steps.

The analysis of granulometry of substances is relevant in a great variety of the research and industrial applications. Unfortunately, image-based algorithms for granulometry analysis are difficult to tune and validate. In a typical setup, one or more cameras acquire images of a scene with a great number of objects or particles that must be measured. The distribution of the sizes/shape characteristics of the elements are the common output of such systems. The creation of supervised image database where the coordinates of all elements are known is very important and it allows for testing in a suitable manner the final size/shape distribution of particles produced by the image processing system with respect to the real distribution. Due to the great amount of objects or particles in the images, it is not often convenient, or even impossible, to individually measure each single objects in order to test the capability of the image processing system to locate and measure the elements (creation of a supervised dataset). One possible solution encompasses the creation of a synthetic image dataset where the position of each elements is known a priori. In this paper we propose a virtual environment to create and test an imagebased granulometric system based on the 3D engine Blender. Results are encouraging and show the effectiveness of the proposed method.

Fractal analysis of the morphology of ice crystal particles in frozen food was attempted for frozen soybean curd (tofu). From a microscopic image analysis of the ice crystal particles, it was found that the perimeter of the ice crystal particles could be recognized as a fractal. Effects of the storage time and storage temperature on the fractal dimension (d p ) of the perimeter of the ice crystal particles were also investigated. As storage time was increased, the d p value tended to decrease. When the storage temperature was increased, the value of d p decreased more rapidly. The changes corresponded to the visual observation of the shape change for the ice crystal particles during storage reported by many researchers, suggesting that the fractal dimension d p could be used as a quantitative indicator reflecting the surface roughness of ice crystal particles.

A new model describing laser noise in terms of non-Markovian stochastic phase jumps has been recently introduced. In this letter an exact expression for the correlation function for the electric field is obtained. This expression, valid for all possible values of the parameters of the stochastic process, reduces to the previously reported approximations. A procedure is described for the inverse problem of determining the stochastic parameters from measured data for real lasers.

Texture segmentation is one of the early steps towards identifying surfaces and objects in an image. Textures considered here are de ned in terms of primitives called tokens. In this paper we h a ve developed a texture segmentation algorithm based on the Voronoi tessellation. The algorithm rst builds the Voronoi tessellation of the tokens that make up the textured image. It then computes a feature vector for each V oronoi polygon. These feature vectors are used in a probabilistic relaxation labeling on the tokens, to identify the interior and the border regions of the textures. The algorithm has successfully segmented binary images containing textures whose primitives have identical second-order statistics and a n umber of gray level texture images.

UWB systems based on impulse radio have the potential to provide very high data rates over short distances. In this paper, a new pulse shape is presented that satisfies the FCC spectral mask. Using this pulse, the link budget is calculated to quantify the relationship between data rate and distance. It is shown that UWB can be a good candidate for high rate transmission over short ranges, with the capability for reliably transmitting 100 Mbps over distances at about 10 meters.

In this paper, we propose an approach to the problem of simultaneous shape and refractive index recovery from multispectral polarisation imagery captured from a single viewpoint. The focus of this paper is on dielectric surfaces which diffusely polarise light transmitted from the dielectric body into the air. The diffuse polarisation of the reflection process is modelled using a Transmitted Radiance Sinusoid curve and the Fresnel transmission theory. We provide a method of estimating the azimuth angle of surface ...

Abstract : This report describes the research effort which was undertaken to extend the capability of numerical techniques developed for computing Magnus effects over right circular cones to artillery projectile shapes of interest to the Army. The changes involved: (1) introduction of longitudinal pressure gradient effects in the boundary layer equations; (2) introduction of turbulent transport properties into the boundary layer equations; (3) modification of the inviscid flow computation for a more general body configuration; and (4) modification of the technique for computing the three dimensional displacement surface. (Author)

We explore a location-based approach for behavior modeling and abnormality detection. In contrast to the conventional object-based approach where an object may first be tagged, identified, classified, and tracked, we proceed directly with event characterization and behavior modeling at the pixel(s) level based on motion labels obtained from background subtraction. Since events are temporally and spatially dependent, this calls for techniques that account for statistics of spatio-temporal events. Based on motion labels, we learn co-occurrence statistics for normal events across space-time. For one (or many) key pixel(s), we estimate a co-occurrence matrix that accounts for any two active labels which co-occur simultaneously within the same spatio-temporal volume. This co-occurrence matrix is then used as a potential function in a Markov Random Field (MRF) model to describe the probability of observations within the same spatio-temporal volume. The MRF distribution implicitly accounts for speed, direction, as well as the average size of the objects passing in front of each key pixel. Furthermore, when the spatio-temporal volume is large enough, the co-occurrence distribution contains the average normal path followed by moving objects. The learned normal co-occurrence distribution can be used for abnormal detection. Our method has been tested on various outdoor videos representing various challenges.

Image segmentation is not only hard and unnecessary for texture-based image retrieval, but can even be harmful. Images of either individual or multiple textures are best described by distributions of spatial frequency descriptors, rather than single descriptor vectors over presegmented regions. A retrieval method based on the Earth Movers Distance with an appropriate ground distance is shown to handle both complete and partial multi-textured queries. As an illustration, different images of the same type of animal are easily retrieved together. At the same time, animals with subtly different coats, like cheetahs and leopards, are properly distinguished.

Short term electricity load forecasting is nowadays, of paramount importance in order to estimate next day electricity load resulting in energy save and environment protection. Electricity demand is influenced (among other things) by the day of the week, the time of year and special periods and/or days such as Ramadhan, all of which must be identified prior to modeling. This identification, known as day-type identification, must be included in the modeling stage either by segmenting the data and modeling each day-type separately or by including the day-type as an input. This paper investigates day-type identification approach for Algerian electricity load. Kohonen maps are used to identify daytypes. The K-Means clustering method will be used as a complementary method to precisely identify the obtained classes. Clustering validity is done by using a criteria measurement of quality. This work has allowed the identification of six different classes.

Quality-of-Service (QoS) management is becoming an important part of Consumer Electronics systems. The complexity of recent multimedia applications and their requirements on the system throughput ask for a parallel programming model which enables parallel task execution. In this paper, we describe a hierarchical QoS model for managing multimedia applications running on a multiprocessor Systems-on-Chip (SoC). We focus on an MPEG-4 shape-texture decoder that is fully object based, using arbitrary object shapes. We specify the QoS problem within the given application domain. First, we explore the possible application scalability. The obtained results save up to 26% of resources. Second, and in contrast with many existing systems, we employ a novel prediction technique for the execution time of video-object decoding in a group of frames, where the actual execution is spent only on data that have a guarantee to be presented. 1 .

pulse is stretched and amplified, it is of too short a duration to set a standard core. The readout voltage The experimental results indicate that the circumncould, however, set logic gates and thus steer the core ferential-turns method of quadrature field sensing is contents in accordance with the information contained simple to fabricate, straightforward to design, and proin the cores. This latter aspect allows conventional core vides useful outputs-experimentally, about 0.1-voltcircuitry to be used and operated in the conventional per-turn output signal at about 3-ampere-turns intermanner, but with the added available feature of a builtrogation current. The method, although not completely in decision capacity. The so-called "level logic" availnondestructive, permits the designer to allow for the able from current and voltage state devices is thus possiloss of flux since it is known for a given sensing level.

This paper describes design and implementation of a vision based platform for automated refueling tasks. The platform is an autonomous docking system in principle, with the specific application-refueling of vehicles. The system is based on monochromatic, monocular vision, and it utilizes very specialized image processing schemes. Image processing consists of very fast filtering and segmenting algorithms, as well as moment's computation. A robotic arm with 6 joints (FANUC M-6i), and a controller unit (R-J3), does the physical work. A serial interface, with very high-level commands, connects a supercomputing machine and the robot's controller. A practical setup would probably be scaled down to a special design robot, and a single processor controller with special VLSI chips for image processing. Results are very promising; the robot can identify the cap position, orientation, and height in real time with acceptable accuracy and reliability.

One of the remaining obstacles to the widespread application of industrial robots is their inability to deal with parts: that are not precisciy po~itioned. In the case of manual asscm'nly, componentq are often presented in bins. Current automated systems, on the olher hand, require separate feeders which present the parts with carefully controlled position and attitude. Here we show how results in rnachicc vision provide techn:ques for automatically directing a mechanical manipulator to pick one object at a time out of a pile. The attitude of the object to be picked up is determined using a histogram of the orientations of visible surface patches. Surface orientation, in turn, is determined using photometric stereo applied to multiple images. These images are taken with the same camera but differing l~ghting. The resulting needle map, giving the orientations of surface patches, is used to create an orientation histograni which is a discrete approximation to the est,ended Gaussian image. This can be rmtched against a synthetic orientation histogram obtsined from protoypica1 models of the objects to be n~anipulated. Such models may be obtained from computer aided design (CAI)) databases. The method thus requires t h a t the shape of the objects be described, but it is not restricted to particular types of objects.

Techniques for color-based tracking of faces or hands often assume a static skin color model. However, skin color perceived by a camera can change when lighting changes. In common real environment multiple light sources impinge on the skin. Therefore, for robust skin pixel detection, a dynamic skin color model that can cope with the changes must be employed. We show that skin detection in video can be enhanced by exploiting the knowledge of the range of possible skin colors for the camera used. In normalized color coordinates this range has a distinct shape we call the skin locus. We developed an adaptive histogram backprojection technique where the skin color model is updated by pixels in the search region which fall in the skin locus. We demonstrate increased detection capability with webcam videos of faces taken successively under daylight, incandescent lamp, fluorescent light and a combination of these light sources.

We propose a unification framework for three-dimensional shape reconstruction using physically based models. A variety of 3D shape reconstruction techniques have been developed in the past two decades, such as shape from stereopsis, from shading, from texture gradient, and from structured lighting. However, the lack of a general theory that unifies these shape reconstruction techniques into one framework hinders the effort of a synergistical image interpretation scheme using multiple sensors/information sources. Most shape-from-X techniques use an “observable” (e.g., the stereo disparity, intensity, or texture gradient) and a model, which is based on specific domain knowledge (e.g., the triangulation principle, reflectance function, or texture distortion equation) to predict the observable, in 3D shape reconstruction. We show that all these “observable–prediction-model” types of techniques can be incorporated into our framework of energy constraint on a flexible, deformable image frame. In our algorithm, if the observable does not confirm to the predictions obtained using the corresponding model, a large “error” potential results. The error potential gradient forces the flexible image frame to deform in space. The deformation brings the flexible image frame to “wrap” onto the surface of the imaged 3D object. Surface reconstruction is thus achieved through a “package wrapping” or a “shape deformation” process by minimizing the discrepancy in the observable and the model prediction. The dynamics of such a wrapping process are governed by the least action principle which is physically correct. A physically based model is essential in this general shape reconstruction framework because of its capability to recover the desired 3D shape, to provide an animation sequence of the reconstruction, and to include the regularization principle into the theory of surface reconstruction.

The purpose of this study was to characterize the form of the pupil in normal human subjects. Using a modified slitlamp, photographs of pupils were taken in steady illumination and 10-20 sec after darkness. Transparencies were projected and digitized, and the pupil margin was represented as a circular Fourier series. Best-fit ellipses were also determined. The placement of the pupil relative to the limbus was determined in a number of subjects. Results from 23 subjects indicated that in both darkness and light, average pupil noncircularity was 0.0166. (A value of 0.0200 is easy to detect with the unaided eye from the photographs.) On average, the best-fit ellipse accounted for about half of the noncircularity (59.6% in darkness; 47.7% in light). Most of the contribution to shape was made by the first 4 or 5 harmonics. Shapes were usually stable within a session and could remain fairly stable for at least a year; however, shapes for different subjects were not very similar, especially in the light. (Average pairwise similarity: 0.106 in darkness; 0.034 in light; similarity can have values from-1 to I.) For a given subject, shapes in light and dark were often fairly similar (average similarity 0.260), but there were systematic differences: in eyes where the ellipse contributed > 20% ofnoncircularity, ellipse major axes clustered around vertical in darkness, and horizontal in light, implying greater contraction near the vertical meridian. Even pupils with little elliptical contribution turned out to contract more near the vertical meridian. There was some tendency for left and right eyes of an individual to show mirror symmetry of shape. In the dark, pupils were located 0.27 + 0.09 mm nasal and 0.20 + 0.15 mm superior to the fimbus center, and usually moved slightly further nasal or superior in the light. Noncircularity increased with age (0.0015/decade). It was concluded that pupils show individuality of shape, with significant regularities within and across subjects.

MUVIS is a series of CBIR systems. The first one has been developed in late 90s to support indexing and retrieval in large image databases using visual and semantic features such as color, texture and shape. During recent years, MUVIS has been reformed to become a PC-based framework, which supports indexing, browsing and querying of various multimedia types such as audio, video, audio/video interlaced and several image formats. MUVIS system allows real-time audio and video capturing, encoding by last generation ...

In competitive electricity markets, the distribution service providers have been given new degrees of freedom in formulating dedicated tariff offers to be applied to properly defined customer classes. For this purpose, they may take advantages from identifying the consumption patterns of their customers and grouping together customers exhibiting similar load diagrams. In this paper, we report on results obtained by using various unsupervised clustering algorithms (modified follow-the-leader, k-means, fuzzy k-means and two types of hierarchical clustering) and the Self Organising Map to group together customers having a similar electrical behaviour. The customer classification is investigated in the paper by considering a set of 234 non-residential customers. Each customer is characterised by a set of values extracted from the load diagrams in a given loading condition. The effectiveness of the classifications obtained with the various algorithms has been compared in terms of a set of adequacy indicators based on properly defined metrics, some of which have been originally developed by the authors. The results show that the modified follow-the-leader and one type of hierarchical clustering exhibit better characteristics than the ther algorithms in terms of adequacy. o

Software conflicts arising because of conflicting changes are a regular occurrence and delay projects. The main precept of workspace awareness tools has been to identify potential conflicts early, while changes are still small and easier to resolve. However, in this approach conflicts still occur and require developer time and effort to resolve. We present a novel conflict minimization technique that proactively identifies potential conflicts, encodes them as constraints, and solves the constraint space to recommend a set of conflict-minimal development paths for the team. Here we present a study of four open source projects to characterize the distribution of conflicts and their resolution efforts. We then explain our conflict minimization technique and the design and implementation of this technique in our prototype, Cassandra. We show that Cassandra would have successfully avoided a majority of conflicts in the four open source test subjects. We demonstrate the efficiency of our approach by applying the technique to a simulated set of scenarios with higher than normal incidence of conflicts.

A program which recognizes real roads, their intersections, and objects which are road-like is presented. Although the work has been strongly motivated by the real roads as they are seen from the ERTS satellite, the visual model of a road can be used for recognition of any road-like objects. This model is structured in such a way that it can handle real roads as well as rivers and streams as they are seen on satellite pictures, tracks in bubble chambers, and veins under the appropriate magnification.

In this work it is suggested that color induces phenomenal wholeness, part-whole organization and fragmentation. The phenomenal wholeness subsumes the set of its main attributes: homogeneity, continuity, univocality, belongingness, and oneness. If color induces wholeness, it can also induce fragmentation. Therefore, in order to understand the role played by color within the process of partwhole organization, color is used both as a wholeness and as a fragmentation tool, thus operating synergistically or antagonistically with other wholeness processes. Therefore, color is expected to influence figure-ground segregation, grouping, shape formation and other visual processes that are related to the phenomenal wholeness. The purpose of this study is to rate the influence of color in inducing whole and part-whole organization and, consequently, in determining the perception of figure-ground segregation, grouping, shape formation, numerousness evaluation and time reading. We manipulated experimental conditions by using equiluminant colors to favor or break (parcel-out) the wholeness of objects like geometrical composite figures and words. The results demonstrated that color is aimed, among other psychological and biological purposes, at: (1) relating each chromatic component of an object, thus favoring the emergence of the whole object; (2) eliciting a part-whole organization, whose components are interdependent; (3) eliciting fragments and then breaking up the whole and favoring the emergence of single components. Wholeness, part-whole organization and fragmentation can be considered as three further purposes of color.

The growth of the brain of human embryo is changing through a long time in the body of mother. So it is very difficult to observe and to understand that process. Therefore, the embryologists found the realistic human organ models and animations necessary for their studies. But to create the realistic human embryo brain models and to do the animations it requires an appropriate methodology. The aim of this paper is to present a developing methodology based on the functional representation and the convolution of the surfaces . We employed this to create a growth simulation of the human embryo brain. The idea of this technique is the following. As a first step the 2D central skeleton is created from an artistic drawing and then the 3D skeleton is modeled by adding the thickness. As the next step, the skeletons representing key-frame models are used to create an animation. At the end the gap between the key-frame models is filled by the suitable interpolation techniques and finally the animation is composed.

Registration of partial scan data sets is still a challenge for today's CAD systems and CAD system users. Many of the known methods rely on user interaction or feature recognition. For non-regular users this is too time consuming and errorprone. The paper describes a method to register partial scan data by fitting a large fat tetrahedron (LFT) in the target point cloud. The method is computational intensive and in its CPU implementation not fit for interactive use. The independency of the points in the data-sets makes massive parallel computing applicable. The paper describes the implementation of the method on a GTX260 GPU using the CUDA programming environment. A performance gain of 10 times compared to a conventional CPU implementation was achieved, which can be further improved by implementing a pre selection method of the result, bringing interactive use in range after further optimization.

In 1976, B. J. Carroll derived the equation to show that a symmetric liquid droplet sitting on a thin cylindrical fiber would acquire a bell shape at equilibrium. We have extended his derivation to describe a drop located at the top end of a vertical, cylindrical fiber. By minimizing the Gibbs free energy of the drop at the fiber tip, it was found that the drop consists of two portions, a spherical cap on the fiber tip and a full, symmetrical bell located on the fiber body adjacent to the fiber tip. The experimental verification of the predicted shapes was performed using water, ethylene glycol, and Kaydol drops on nylon cylindrical fibers. Only four parameters are required to obtain agreement between the theoretical shape and the observed shape: the drop volume, the fiber radius, the surface tension of the liquid, and the Young contact angle of the liquid on a flat surface of the same composition as the fiber.

Object classification often operates by making decisions based on the values of several shape properties measured from the image. This paper describes and tests several algorithms for calculating ellipticity, rectangularity, and triangularity shape descriptors.

Communicated by (xxxxxxxxxx) Recent works in geometric modeling show the advantage of local differential coordinates in various surface processing applications. In this paper we advocate surface representation via differential coordinates as a basis to interactive mesh editing. One of the main challenges in editing a mesh is to retain the visual appearance of the surface after applying various modifications. The differential coordinates capture the local geometric details and therefore are a natural surface representation for editing applications. The coordinates are obtained by applying a linear operator to the mesh geometry. Given suitable deformation constraints, the mesh geometry is reconstructed from the differential representation by solving a sparse linear system. The differential coordinates are not rotation-invariant and thus their rotation must be explicitly handled in order to retain the correct orientation of the surface details. We suggest two methods for computing the local rotations: the first estimates them heuristically using a deformation which only preserves the underlying smooth surface, and the second estimates the rotations implicitly through a variational representation of the problem. We show that the linear reconstruction system can be solved fast enough to guarantee interactive response time thanks to a precomputed factorization of the coefficient matrix. We demonstrate that our approach enables to edit complex meshes while retaining the shape of the details in their natural orientation.

In this paper the method of processing the concave polygon class is presented. This method is implemented as a part of the system of shape understanding (SUS) and tested on the broad classes of shapes. The system of shape understanding is able to perform different tasks of shape analysis and recognition based on the ability of the system to understand the different concepts of shape on the different levels of cognition, The system consist of different types of experts that perform different processing and reasoning tasks. The concave polygon class model and processing methods are also described.

In this paper, we present a novel haptic technique for emulating hard surfaces with high realism; such a technique has significant potential utility in certain orthopedic surgery applications such as joint replacement surgery where the goal is to prevent incursions beyond a virtual surface during bone cutting operations. The Dynamic Physical Constraint (DPC) concept uses a unidirectional physical constraint that is actively positioned to limit movement between two manipulator links; the concept is applicable to providing virtual constraints in both 2D and 3D workspaces. Simulation results demonstrate the potential feasibility of the concept, and a prototype device was built for testing. The DPC device provides a convincing sensation of a real, hard virtual surface which can be smoothly tracked when the end effector is in contact with the surface. Incursion across the surface with the prototype was well submillimetric and within the accuracy constraints required for joint replacement applications.

Corner detection is widely used in image processing and machine vision. Hence, different corner detectors are proposed. But the performance of such corner detectors is sensitive to round effect and curve shape of the edges. In this paper we propose a novel corner detector that either over come corner detection problems and produces some information about detected corners that is very useful in segmentation and object recognition.

This paper presents an adaptive method for polygonization of implicit surfaces. The method insists on the shape of triangles and the accuracy of resulting approximation as well. The main advantages of the triangulation presented are simplicity and the stable features that can be used for next expanding. The implementation is not complicated and only the standard data structures are used. The presented algorithm is based on the surface tracking scheme and it is compared with the other algorithms based on the similar principle, such as the Marching cubes and the Marching triangles algorithms.

A comprehensive review of porosity origin, microstructure peculiarities, fabrication methods, and mathematical models, as well as systematic experimental data for different porous piezoceramics with 3-0/3-3 connectivity is presented. New families of porous piezoceramics based on lead zirconate titanate (PZT), lead titanate, lead metaniobate, and sodiumpotassium niobate compositions, with properties combining better parameters of PZT, PN-type ceramics, and 1-3 composites are introduced. Piezoelectric resonance analysis methods for automatic iterative evaluation of complex material parameters and the full sets of complex constants for different porous piezoceramics are presented. Numerical FEM calculations were critically compared with the results of various approximated formulas, unit cell models, and experimental data for different porous piezoceramics. Microstructural and physical mechanisms of losses and dispersion in porous piezoceramics, as well as technological aspects of their large-scale manufacture and application in ultrasonic devices were considered. The results of SEM microstructure analysis and microstructure-properties interrelations were discussed. Recent advances in fabrication methods for nano-and microporous piezoceramics and ceramic piezocomposites were discussed.

Osteoporotic hip fracture is associated with high mortality and morbidity and often results in a loss of mobility and independence. Osteoporosis is diagnosed by measuring Bone Mineral Density (BMD), a measure of the amount of mineral in a bone. Although BMD continues to serve well it does not fully account for bone strength and only partially accounts for the risk of hip fracture. The shape and structure of the proximal femur also help to determine how forces act in the hip in a fall and their measurement can aid the prediction of hip fracture.

Using a finite-element method, we have calculated fluxmetric and magnetometric demagnetizing factors and for square cross-section bars as functions of susceptibility and length-to-width ratio over the range = 1 to and = 0 01 to 100. We present the results in figures and tables and compare them with those for cylinders. We give an approximate conjugate relation for ( ) of a cube.

The exploitation of cassava tubers (Manihot utilissima) for various industrial, medicinal and food products requires the removal of the cortex, which is commonly carried out manually. Mechanization of this process has the potential of driving increased cultivation of cassava and generating products with high hygienic standard, product quality, processing efficiency, minimum loss of tubers and increased processing rate. The difficulty in achieving an acceptable peeling efficiency can be attributed to: the irregular shape of the tubers, the non uniformity of the cortex thickness and unavailability of technical data on parameters of design. This paper presents the solution to the cassava peeling problems and the development of a new machine capable of peeling cassava tubers with over 90 % efficiency. Cassava tubers have been classified according to their varieties. The varieties have been characterized. The relationship between tuber diameter and cortex thickness is established. These ...

A new simple algorithm, based on dynamic programming is presented, for handwritten character recognition, with improved accuracy. The proposed Shape Transform (ST) approach is based on the calculation of the cost of transforming the image of a given character into that of another, thus taking into account local geometrical similarities and differences. The effectiveness of the proposed method is compared to the Karhunen Loeve Transform (KLT) method, with which a similar experiment was contacted [1] reporting the best results in the literature. The experiments performed, show that this new approach leads to improved recognition. It is more demanding in computer time, which is becoming ever more plentiful, but it lends itself to very efficient parallel hardware implementation. Character Images Preprocessing Feature Extraction Codebook LVQ Training Eucl. Dist. Recognition Recognition Results KLT

AbstractÐWe show that a translation invariant implementation of min/max filters along a line segment of slope in the form of an irreducible fraction dyadx can be achieved at the cost of P k min/max comparisons per image pixel, where k mxjdxjY jdyj. Therefore, for a given slope, the computation time is constant and independent of the length of the line segment. We then present the notion of periodic moving histogram algorithm. This allows for a similar performance to be achieved in the more general case of rank filters and rank-based morphological filters. Applications to the filtering of thin nets and computation of both granulometries and orientation fields are detailed. Finally, two extensions are developed. The first deals with the decomposition of discrete disks and arbitrarily oriented discrete rectangles, while the second concerns min/max filters along gray tone periodic line segments.

With continued development and improvement of tissue engineering therapies for small articular lesions, increased attention is being focused on the challenge of engineering partial or whole synovial joints. Joint-scale constructs could have applications in the treatment of large areas of articular damage or in biological arthroplasty of severely degenerate joints. This review considers the roles of shape, loading and motion in synovial joint mechanobiology and their incorporation into the design, fabrication, and testing of engineered partial or whole joints. Incidence of degeneration, degree of impairment, and efficacy of current treatments are critical factors in choosing a target for joint bioengineering. The form and function of native joints may guide the design of engineered jointscale constructs with respect to size, shape, and maturity. Fabrication challenges for joint-scale engineering include controlling chemo-mechano-biological microenvironments to promote the development and growth of multiple tissues with integrated interfaces or lubricated surfaces into anatomical shapes, and joint-scale bioreactors which nurture and stimulate the tissue with loading and motion. Finally, evaluation of load-bearing and tribological properties can range from tissue to joint scale and can focus on biological structure at present or after adaptation.