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In digital imaging, computer processes operate on locations or intensities or both. A discrete location transformation changes all the locations of an image in some systematic way. A location transformation can be done geometrically, or numerically, or computationally by matrix arithmetic. Six elementary 1-bit location transformations are defined, with examples and with a program. Symmetry groups are defined, and examples of the rotation, single-translation, and double-translation groups are shown. Gratings are defined, and examples of superimposition of gratings are show. The locations of two images can be combined by program. The count of locations in an image can be reduced (and pixel size increased) by program.

A description of natural signs and natural information is proposed that interprets the presence of natural information as an affordance for the particular animal or species that would interpret it. This solves the reference class problem that undercuts earlier correlational accounts. It explains how there can be natural signs of individuals and also various non-correlational signs. The effect of superimposition of natural signs is then described.

Muscle activities are generally measured with surface electromyography (sEMG). However, the individual muscle activities are quite difficult to obtain because of superimposition of the sEMG signals called "crosstalk problems". The crosstalk is highly complicated in a forearm having a number of muscles in the small volume. A method to resolve the crosstalk to become able to measure individual activities of muscles would be useful. This paper proposes a method for reverse-estimating the individual muscle activities in the forearm from the sEMG distribution using an EMG conduction model. The individual muscle activities were calculated by conforming the measured sEMG distribution to the simulated results of the mathematical model. To verify the reverse-estimation results, physical work experiments were carried out for three subjects applying a flexion load with weights (0.5kg, 0.75kg, 1kg) to the proximal interphalangeal joint of the middle finger. The muscle activation values were calculated from the measured sEMG. The results show there are significant differences (p

Many sensors around the world are consistently collecting the real-time real-world data. The data streams captured by these sensors can give us an idea of what is going on in a specific area; however, it is not easy for humans to understand their spatial and temporal relationships by just looking at them independently. This paper proposes to construct Digital Diorama, a three-dimensional view where viewers can see at a glance how people are moving around the monitored space without violating their privacy, by integrating multiple data streams captured by stationary cameras and RFID readers in real time. Digital Diorama realizes such real-world visualization with the following features: 1) view control, 2) real-time camera image superimposition, and 3) privacy control. We have demonstrated that Digital Diorama for a shopping center was able to present the current positions of persons and real-time camera images in approximately 1 frame per second.

In this work we propose the use of heuristic features to guide an evolutionary approach for 3D range image registration in forensic anthropology. The aim of this study is assist to the forensic experts in one of their main tasks: the cranio-facial identification. This is usually done by the superimposition of the 3D model of the skull on a facial photograph of the missing person. In this paper we focus on the first stage: the automatic construction of an accurate model of the skull. Our method includes a pre-alignment stage, that uses a scatter-search based algorithm and a refinement stage. In this paper we propose a heuristic selection of the starting points used by the algorithm. Results are presented over a set of instances of real problems.

The individual adaptation of seat shells is a very difficult task, especially in the case of disabled patients who are unable to articulate their requirements [1]. Besides the individual body geometry the amount of pressure has to be considered particularly with regard to the patients who use the seat shells all day. Congestion has to be reduced to prevent decubitus [2]. Typically the pressure load is measured by a sensor mats that deliver a 2-dimensional result [3]. To optimize a seat shell under geometrical and pressure aspects the 2-dimensional data of the pressure measurement have to be superimposed with the 3-dimensional surface data of the seat shell.

In software product line engineering, feature composition generates software tailored to specific requirements from a common set of artifacts. Superimposition is a technique to merge code pieces belonging to different features. The advent of model-driven development raises the question of how to support the variability of software product lines in modeling techniques. We propose to use superimposition as a model composition technique in order to support variability. We analyze the feasibility of superimposition for model composition, offer corresponding tool support, and discuss our experiences with three case studies (including an industrial case study).

This study aims to determine facial soft tissue differences among Malays in Peninsular Malaysia by applying geometric morphometric method with digital photograph. The photo was captured using digital SLR camera and analyzed using MorphoStudio™ software. Fifteen homologous landmarks on each 20 frontal facial photo of male subject of Jawa and Rawa were defined and J-links with Procustes means were computed. The results were compared and analyzed using Procrustes superimposition implementation to obtain generalized rotational fit. The Jawa’s male forehead height is longer than Rawa’s, however, the mid-facial region is smaller in size. The Jawa groups show anisotropic shape change with direction of change is more vertical and downwards. Computer aided photogrammetric analysis is capable of depicting and quantifying local shape and size changes of facial soft tissue differences between two Malay Jawa and Rawa groups.

Studies with mammograms have demonstrated a relationship between parenchymal texture and breast cancer risk. Although promising, texture analysis in mammograms is limited by the effect of tissue superimposition. Digital Breast Tomosynthesis (DBT) is a novel tomographic x-ray breast imaging modality that alleviates the effect of tissue superimposition. We explore the potential advantages of DBT texture analysis for breast cancer risk estimation. We analyzed bilateral DBT and DM images from 39 women, and compared the performance of the computed texture features in (i) reflecting characteristic parenchymal properties, and (ii) correlating to mammographic breast density, an established surrogate of breast cancer risk. Strong texture correlation was observed between contralateral and ipsilateral breasts, indicating that parenchymal properties are potentially inherent to an individual woman. Compared to DM, DBT texture features demonstrated a stronger correlation with breast density. Although preliminary, our results show that DBT texture analysis could potentially improve breast cancer risk estimation.

Superimposition is a composition technique that has been applied successfully in several areas of software development. In order to unify several languages and tools that rely on superimposition, we present an underlying language-independent model that is based on feature structure trees (FSTs). Furthermore, we offer a tool, called FSTComposer, that composes software components represented by FSTs. Currently, the tool supports the composition of components written in Java, Jak, XML, and plain text. Three nontrivial case studies demonstrate the practicality of our approach.

The theorem presented in this paper is a general solution for the optimal superimposition between two protein structures, which is actually the problem of the weighted optimal rigid superimposition between two vector sets with the same size. The theorem gives not only the rotational and translational parameters, but also the minimal value of the mean squared deviation of the optimal superimposition.

Today, a lung examination without X-rays is incomplete (Krause 1909). This sentence is still valid today, however it was the quintessence of a study in 1909. Even today, chest X-rays continue to be important in the visualization of thoracic anatomy and in the depiction of pathological conditions. However, it is well known that the limitations of X-rays are due to superimposition of various structures on an image. Even though it is possible to view the chest in two perpendicular planes (frontal and lateral views), the problems associated with the superimposition exclude high sensitivity in the detection of chest abnormalities when using projection radiography.

The link between biological form and function is well known, and is assumed to hold true at the molecular level. Since identifying similar protein structures is the first step in identifying similar functions, much effort has been placed in developing methods to detect structural similarity. Several methods exist, including: SCOP [8], the DALI algorithm (from the FSSP Database [6]), the VAST algorithm (from the MMDB database [5]), and Root Mean Square (RMS) superimposition [9]. The latter three provide quantitative metrics describing protein similarity on an objective, continuous scale. Statistical analyses can then be performed on similarity scores for a set of proteins, to obtain a plot of ‘protein structure space’ [7]. Before such analyses are done however, one must be sure that the metric used accurately represents similarity.

Today, a lung examination without an X-ray is incomplete (Krause 1909). While this sentence is still valid today, it was the quintessence of a study in 1909. Even today, chest X-rays continue to be important in the visualization of thoracic anatomy and the depiction of pathological conditions. However, it is well-known that the limitations of X-rays are due to superimposition of various structures on an image. Even though it is possible to view the chest in two perpendicular planes (frontal and lateral views), the problems associated with the superimposition exclude high sensitivity in the detection of chest abnormalities when using projection radiography.

A current challenge in augmented reality applications is the ability to superimpose synthetic objects on real objects within the environment. This challenge is heightened when the real objects are in motion and/or are non-rigid. Yet even more challenging is the case when the moving real objects involved are deformable. In this article, we present a robust method for calibrating marker-based augmented reality applications to allow real-time, optical superimposition of synthetic objects on dynamic rigid and simple-deformable real objects. Moreover, we illustrate this general method with the VRDA Tool, a medical education application related to the visualization of internal human knee joint anatomy on a real human knee.

We describe our experience with neuronavigation in 140 operated cases. We propose the systematic use of MR for the operative imaging and describe our results concerning the precision of procedures as a function of models of markers. The study of postoperative MR shows best tumoral resection of infiltrating gliomas and a smaller injury for the cerebral parenchyma. The best system of neuro-navigation is that associating a good mechanical precision of the guiching system guidance to optical techniques for superimposition of contours in the operative microscope.

The diagnosis of mandibular and temporomandibular pathology is difficult task because of the morphological changes associated with trauma, deformities, degenerative disorders or neoplasms. Three-dimensional computed tomography (3-D CT) has been introduced as an important aid in the assessment of craniofacial bones including the mandible [5], especially in the setting of skeletal deformities [4, 7], trauma [1] and preoperative evaluation [6, 8]. Because reproducibility is essential for inter— and intraindividual comparison of 3-D CT examinations, the lack of standardization of 3-D image views represent a relevant clinical and radiological question. In the routine different views from any projection may be obtained resulting in different 3-D studies, which depend on the specific clinical cases and physician. Moreover, some 3-D image projections may not be adequate to demonstrate particular findings according to the superimposition of bony structures or artefacts.

Picture archiving and communication systems (PACS) were originally designed to enable widespread use of radiographic images at various locations utilizing central archives and network communication. We consider one further application of a PACS even more important, i.e. the superimposition of images of different imaging modalities for synoptic interpretation. We integrated the equipment of the Nuclear Medicine Department in our existing PACS to facilitate the superimposition of magnetic resonance images and scintigrams for the diagnosis of suspect recurrencies after rectal cancer. The synoptic interpretation by this image fusion enhanced the specificity of the investigation to the value of 1.

Conventional radiographs arise from the projection of a volume and, as a result, show superimpositions. The role of the radiologist is the extraction of normal and pathological details that can be interpreted in terms of three-dimensional structures. Superimposition was overcome by scanning. Translation of the scans in the third dimension requires a capacity of imagination only gained after extensive training. It is therefore not surprising that three-dimensional imaging encounters an enthusiastic response from surgeons.

The first part of this paper is devoted to the analysis and verification of methods derived from that of WICKSELL which allows deduction of the cell volume histogram from the histogram of cell section diameters. The second part emphasiezs the difficulties involved in the interpretation of the cell volume histogram: if it is multimodal can one conclude that it is composed of sub-histograms defined by some biological reality ? And if it is unimodal does this mean that it represents a single population or a superimposition of gaussian populations. In the last case, how does one determine the statistical law attributed to a subpopulation ?

It is well known that the discovery of the X-ray represented a major advance in medical science, since it allowed for the first time a non-invasive, direct confirmation of morphological alterations suspected by the physician during physical examination. While the conventional radiograph is a highly valuable method of diagnosis, it is static because fourth-dimensional or dynamic information (i. e., rapid alteration over time) is not provided and third-dimensional information is obscured by the superim- position of anatomic structures. The limitation of the fourth dimension has been solved by following radioopaque tracers through organ systems using rapid-imaging techniques (e. g., cineangiography). However, the problem of superimposition still makes it difficult, and often impossible, to distinguish, unambiguously, one anatomic structure from another, especially when there are only small differences in X-ray density. These kinds of problems are usually overcome by making a number of X-ray pictures from different angles, in which anatomic structures appear in different relationships to one another.

The superimposition of many images has occasionally been used in astronomy to improve the limiting magnitude of photographs (See Richter 1975 and references therein). More recently, photographic amplification has also proved to be a powerful technique for revealing faint objects on deep photographic plates (For references see Malin 1984). This paper reports on the combination of the techniques and the superimposition of the photographically amplified film derivatives obtained from a series of 36 sky-limited plates of the same field.

A wedge filter placed in the useful beam of a megavolt therapy unit produces a tilting of the dose distribution to the beam axis. Appropriate superimposition of several fields can produce a uniform dose in the volume to be treated. Wedge filters are useful in the treatment of tumors in the region of the head and the neck. Their use is, however, not restricted to these areas. Wedge filters are used to influence the isodoses of moving beams as well.

Attempts to photograph sequential sections through a specimen so the images could be viewed using a movie projector extend hack to the early part of the twentieth century (Bush, 1952; Michaelis, 1955; Reicher, 1907). Most efforts have involved making prepared slides of the sections and superimposing the successive images by judging the alignment while viewing the specimen through the microscope or by photographing projected images from the microscope slides. The major difficulties of these systems include the determination of points of reference within the specimen for superimposition, excessive time consumption and labor and obtaining uniform material the successive sections of which are superimposable. Some recent efforts (Postlethwait, 1963; Zimmermann, 1965) involving staining and photographing the specimen surface prior to removal of each section have met with reasonable success.