摘要:

AbstractThe algebraic method as a formal approach in the design and development of the program has earned attention. The authors, in order to examine its usefulness, have defined the algebraic language ASL and constructed the ASL program developing system. But many problems concerning the compiler remain to be solved. The algebraic language ASL contains an abstract sequential machine style of description, and there exists a large number of problems that can be described in a natural way by this style. This paper proposes a method of constructing the compiler for the abstract sequential machine style program in the ASL program development system as well as of improving the execution efficiency of the object code. The usefulness of those methods are examined.

ISSN:0882-1666    

DOI:10.1002/scj.4690230701

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractDistributed algorithms for computing the connectivity of an asynchronous computer network with faulty computers and links are investigated. Computers which are adjacent to faulty computers and links are assumed to be capable of detecting the faults. The existence and efficiency of distributed algorithms depend on the kinds of information each computer is allowed to have on the network before executing an algorithm.Here, the case in which computers fail and the case in which only links fail are considered separately. It is shown that in the former case there is no algorithm for computing the connectivity regardless of the kind of information a computer has about the network. In the latter case the existence of a distributed algorithm, upper and lower bounds of communication complexity and ideal time complexity are discussed for the following three cases: each computer has only the basic information (its identifier and the number of links connected to it); each computer has the basic information and the identifier of the adjacent computers; and each computer has the basic information and the size of the network.

ISSN:0882-1666    

DOI:10.1002/scj.4690230702

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper attempts to relate the testing phase, which is the final stage of the software development and the operation phase after the release. It discusses the occurrence of the software failure due to the errors latent in the software. The event of detecting the software error in the testing phase is described by the software reliability growth model based on a nonhomogeneous Poisson process.As to the assessment of the software reliability in the operation phase, i.e., the operational reliability, three assessment techniques are discussed. They are the method to introduce the environment factor considering the number of errors remaining at the end of the testing, the method based on the hazard rate, and the method based on the cumulative failure rate. Finally, the result of the analysis of the software reliability data is presented. Numerical examples of the assessment methods for the operational reliability are discussed and the results are compared.

ISSN:0882-1666    

DOI:10.1002/scj.4690230703

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractIf multiple‐valued digital systems can be extended to higher‐valued digital systems, potential advantages of high information density and efficient multiple‐valued hardware algorithms will be utilized.This paper presents set‐valued logic networks based on biodevices to construct ultrahigher‐valued digital systems. The biodevices detect specific substrate molecules in solution using specificity enzymes and broadcast specific molecules to perform computation.To design biodevice networks systematically, the concept of set‐valued logic is developed in which molecular information is considered a set of logic values characterized by varieties of molecules. The set‐valued logic enables 2r‐valued computation to be achieved usingrkinds of substrate molecules. It is shown that arbitrary set‐valued logic functions can be realized by highly parallel and very regular biodevice networks. Consequently, an approach to a parallel computing system without the restriction of interconnection prob

ISSN:0882-1666    

DOI:10.1002/scj.4690230704

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper describes a method to determine the three‐dimensional (3‐D) structure of a room environment using lines viewed by a moving camera, assuming that the speed of the camera movement can be measured. The rotational components of the camera are estimated from the movement of the vanishing point formed by horizontal lines in a recorded image. Inclined lines in the image are eliminated from it using the difference in the properties of motions of the inclined lines and the horizontal lines in the image. The locus of the movement of the camera and the 3‐D structure of the environment are determined based on the obtained rotational components of the camera. The accuracy of this method is improved by applying the Kalman filters to the large amount of data involved when the camera rotation and the 3‐D positions of objects in the environment are cal

ISSN:0882-1666    

DOI:10.1002/scj.4690230705

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractFunctional electrical stimulation (FES) has been studied intensively in recent years. In FES, the muscle or nerve of the tetraplegic patient with damage in the central nervous system is stimulated electrically to contract the muscle, aiming at the restoration of the lost function. When the closed‐loop control is employed in FES to control the two joints of the knee and the ankle simultaneously, the inertia arising from the movement of the upper (knee) joint, operates as an external disturbance to the lower (ankle) joint, and deteriorates its transient response. As a result, it is required to construct a control system with a high suppression ability for the external disturbance.It is noted in this study that the stiffness of the human joint, i.e., the difficulty to move (mechanical impedance), is one of the factors which determines the motion of the joint, and the external disturbance affects the motion less if the difficulty to move is enhanced.Further, it is noted that the mechanical impedance of the joint is increased when the tension of the antagonist muscle is increased. Then a method is devised in which the mechanical impedance of the joint is adjusted by controlling the tension of the antagonist muscle in parallel to the control of the joint angle by the agonist muscle.By increasing the mechanical impedance of the joint using this method, a system can be constructed which suppresses the effect of the external disturbance from the motion of the other joint. The proposed system is applied to the control of the ankle joint, and it is shown that the effect of the knee joint movement is suppresse

ISSN:0882-1666    

DOI:10.1002/scj.4690230706

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractAlthough objects in most computer vision have been assumed to be “solid bodies,” this assumption is not always true in practice; for example, a horse can be an object. It has been known that humans recognize such an object by dividing it into several parts, each of which has a recognizable feature. This process is important also for computer processing.This paper proposes pattern recognition of a silhouette of an animal using the relative position of each part of its body. The process is to segment each region of the silhouette and to describe the characteristic of each part and the relationship between a part and its adjacent part.A new method, the “ellipsoid‐expansion method,” based on an ellipsoid fitting, is proposed to segment a silhouette. This method uses an ellipse which is fitted to a region by expanding the ellipse and by producing a reaction when the expanded ellipse exceeds the contour of the region. This method is not influenced by details of the shape of the object and withstands shifts, change of scaling, and rotation of the shape. Recognition of each part of the silhouette of an animal is tested by identifying the description of each part of a basic model of the animal and the description of its silhouette. Examples of identification of animals are carried out using some sim

ISSN:0882-1666    

DOI:10.1002/scj.4690230707

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractHuman motion plays a very important role in daily communication. If computers can directly read the meaning of human motion, man‐machine interaction will be improved. This paper presents a three‐dimensional head motion detection system called “headreader.” A simple but very fast algorithm is used which exploits the contrast of hair and face to recognize face orientation. The system extracts the head and face area and then estimates the head motion parameters from the change in position of each area centroids. The head motion is computed at nearly seven frames per second on an SUN4 work

ISSN:0882-1666    

DOI:10.1002/scj.4690230708

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThis paper discusses the method of automatically extracting the intracranial region from the X‐ray CT image and measuring its volume. In craniofacial surgery, the predicted increase of the intracranial volume after surgery is the important criterion to evaluate the effectiveness of the surgery.By applying the three‐dimensional (3‐D) image processing and the shape interpolation, a method is devised which almost automatically extracts the intracranial region and measures its volume. The processing method and the result of measurement are reported herein. The method can be applied to measure the intracranial volume before the surgery, after the surgery, and the intracranial volume simulated before the surgery for the postoperative skull. The feature of the method is that the intracranial volume can be determined for the post‐surgical and planned skull, even if there exists a number of holes due to the

ISSN:0882-1666    

DOI:10.1002/scj.4690230709

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractMany human activities are based on visual recognition of a scene. Development of scene recognition capability on computer is essential to the development of an intelligent robot.This paper proposes a three‐dimensional (3‐D) object recognition system using functional models. In conventional geometric model‐based recognition, one reference model must be provided for each possible object shape in the same category. This paper proposes a functional model that will allow flexibility in representation of objects belonging to the same category.Experiments were conducted to provide measurement data for demonstrating this functional model‐based object recognition technique. Scene segmentation uses both gray scale image and range image to provide superior segmentation results. The performance of a functional model‐based method for recognizing objects with different shapes that belong to the same functional category is dem

ISSN:0882-1666    

DOI:10.1002/scj.4690230710

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY