bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using soft computing techniques for improving foot trajectories in walking machines
Authors: Garcia Elena , Gonzalez‐de‐Santos Pablo 
Published: August 2002

AbstractWalking machines have been investigated during the last 40 years and some basic techniques of this field are already well known. However, some aspects still need to be optimized. For instance, speed seems to be one of the major shortcomings of legged robots; thus, improving leg speed has been chosen as the main aim of this work. Although some algorithms for optimizing trajectory control of robot manipulators already exist, we propose a more computationally efficient method that employs fuzzy set theory to involve real dynamic effects over leg motion instead of an inaccurate mathematical model. In this article, we improve leg speed by automatically tuning the acceleration of legs. For this purpose, we define fuzzy rules based on experiments and we find the optimal acceleration for every given trajectory. A simple fuzzy inference system is used to compute the required acceleration. It is based on five rules using three linguistic variables. Final results show that foot acceleration tuning for straight trajectory generation is a suitable method for achieving accurate, smooth and fast foot movements. Also it is shown that under some conditions average leg speed can be increased up to 100% using the control methods herein proposed. © 2001 John Wiley & Sons, Inc.
Development and application of wire‐actuated haptic interfaces
Authors: Melchiorri Claudio , Vassura Gabriele 
Published: August 2002

AbstractHaptic devices are being used in ever more applications, ranging from training to education, entertainment, design, space experiments, and so on. In this paper, alternative solutions are presented for the mechanical design of such devices, different from the classical ones based on “rigid” kinematic chains. These solutions adopt actuated wires, and present some features that can be very useful in particular applications. Due to their mechanical construction, these devices offer some peculiar control problems, which must be properly addressed for their use. These aspects (and other possible applications) are discussed, and an example of such a device for visually impaired persons is illustrated. © 2001 John Wiley & Sons, Inc.
Haptic display for human interaction with virtual dynamic environments
Authors: Ruspini Diego , Khatib Oussama 
Published: August 2002

AbstractHaptics is an emerging technology that permits direct “hands‐on” interaction with a virtual environment. A haptic device uses mechanical actuators to physically push a user's finger or hand to give the sensation that he or she would have when interacting with a real physical environment. These force feedback systems have many applications, from training a surgeon to perform an operation, to assisting a child in understanding the behavior of a lever or pulley. In this paper we discuss methods and techniques to allow realistic and robust haptic interactions between a human and a complex dynamic virtual environment. Beyond modeling object penetration constraints, this work demonstrates how shading, friction, texture, and dynamics can be generated to create compelling and realistic virtual worlds. © 2001 John Wiley & Sons, Inc.
Cube Ramsey numbers are polynomial
Authors: Lingsheng Shi 
Published: August 2002

AbstractLet R(G) be the least integer p such that for all bicolorings of the edges of complete graph Kp, at least one of the monochromatic subgraphs contains a copy of G. We show that for any positive constant c and bipartite graph G=(U, V; E) of order n where the maximum degree of vertices in U is at most $c\,{\rm log}\,n,\,R(G) < n^{1+(c+\sqrt{c^2+4c})/2+o(1)}.$ In particular, this shows that the Ramsey number of the n‐cube Qn satisfies $R(Q_n)<2^{(3+\sqrt{5}n/2+o(n)}$ which improves the bound 2cn log n due to Graham, Rödl, and Ruciński. © 2001 John Wiley & Sons, Inc. Random Struct. Alg., 19: 99–101, 2001
IP routing issues in satellite constellation networks
Authors: Wood L. , Clerget A. , Andrikopoulos I. , Pavlou G. , Dabbous W. 
Published: August 2002

AbstractThe growth in use of Internet‐based applications in recent years has led to telecommunication networks transporting an increasingly large amount of Internet Protocol (IP)‐based traffic. Proposed broadband satellite constellation networks, currently under development, will be required to transport IP traffic. A case can be made for implementing IP routing directly within the constellation network, in order to transport IP traffic well and to provide good support for IP multicast and for emerging IP‐based quality of service (QoS) guarantees. This paper examines strategies for implementing and operating IP routing effectively within satellite constellation networks, given known constraints on the constellation resulting from satellite mobility, global visibility, routing and addressing. Copyright © 2001 John Wiley & Sons, Ltd.
A new opportunity for EHF propagation experiments: the EXPRESS campaign with the satellite STENTOR
Authors: Lemorton Joël , Castanet Laurent , Huot Valéry , Marsault Thierry 
Published: August 2002

AbstractSTENTOR is a collaborative programme between CNES, France Telecom, Alcatel Space and Astrium Space. The STENTOR satellite is planned to be launched in the autumn of 2001. Apart from the Ku‐band telecommunication payload designed to test active antennas and digital transponders, an EHF payload funded by DGA (Délégation Générale pour l'Armement=French Ministry of Defence) will be devoted to propagation and transmission experiments. The transmission mission uses a 44/20 GHz transparent repeater and is aimed to test new signal processing methods in the context of future military satellite telecommunication systems. The propagation mission will consist of two high‐frequency beacons, the first one at 20.7 GHz and the second one at 41.4 GHz with a European and an Equatorial coverage. The propagation experiment called EXperimentation of PRopagation in the EHF‐band from STENTOR Satellite (EXPRESS) will be devoted to the evaluation of the influence of propagation impairments on future satellite communication systems and will provide a new opportunity for EHF experimenters. The objective of this paper is to give the information available on this project. Copyright © 2001 John Wiley & Sons, Ltd.
The distinction between key ideas in teaching school physics and key ideas in the discipline of physics
Authors: Deng Zongyi 
Published: August 2002

AbstractThe distinction between key ideas in teaching a high school science and key ideas in the corresponding discipline of science has been largely ignored in scholarly discourse about what science teachers should teach and about what they should know. This article clarifies this distinction through exploring how and why key ideas in teaching high school physics differ from key ideas in the discipline of physics. Its theoretical underpinnings include Dewey's (1902/1990) distinction between the psychological and the logical and Harré's (1986) epistemology of science. It analyzes how and why the key ideas in teaching color, the speed of light, and light interference at the high school level differ from the key ideas at the disciplinary level. The thesis is that key ideas in teaching high school physics can differ from key ideas in the discipline in some significant ways, and that the differences manifest Dewey's distinction. As a result, the article challenges the assumption of equating key ideas in teaching a high school science with key ideas in the corresponding discipline of science, and the assumption that having a college degree in science is sufficient to teach high school science. Furthermore, the article expands the concept of pedagogical content knowledge by arguing that key ideas in teaching high school physics constitute an essential component. © 2001 John Wiley & Sons, Inc. Sci Ed 85:263–278, 2001.
Application of reinforcement learning based on on‐line EM algorithm to balancing of acrobot
Authors: Yoshimoto Junichiro , Ishii Shin , Sato Masa‐aki 
Published: August 2002

AbstractThe acrobot is a two‐link robot, actuated only at the joint between the two links. It is a difficult task in reinforcement learning (RL) to control the acrobot because it has nonlinear dynamics and continuous state and action spaces. In this article, we discuss applying the RL to the task of balancing control of the acrobot. Our RL method has an architecture similar to the actor‐critic model. The actor is a controller that yields a control signal for the current state. The critic predicts the expected return in the future. The actor and the critic are approximated by normalized Gaussian networks, which are trained by an on‐line EM algorithm. We also introduce a new method to promote the critic's learning. Our computer simulation shows that our method is able to acquire fairly good control through a small number of learning trials. © 2001 Scripta Technica, Syst Comp Jpn, 32(5): 12–20, 2001
Keyword spotting using F0 contour information
Authors: Yamashita Yoichi , Iwahashi Daisuke , Mizoguchi Riichiro 
Published: August 2002

AbstractGenerally, keyword spotting is based on the phonemic information. Consequently, if the input speech contains a phoneme sequence which is similar to the keyword, it may be incorrectly detected as the keyword, even though the prosodic pattern such as accent differs greatly. In order to avoid such a false alarm, this paper presents a method where not only the phonemic information, but also the F0 information, are both used to determine the likelihood of the input speech as the keyword. The F0 contour of the keyword is registered beforehand as the template. The F0 contour of the input speech and the template are compared by DP matching, and the likelihood as the keyword is evaluated by the obtained dissimilarity and the phonemic likelihood. Based on an experiment using news broadcasts, it is seen that the false alarm rate is reduced by 30 to 50%, for the equivalent detection rate. © 2001 Scripta Technica, Syst Comp Jpn, 32(7): 52–61, 2001
Obstacle location estimation using planar projection stereopsis method
Authors: Onoguchi Kazunori , Takeda Nobuyuki , Watanabe Mutsumi 
Published: August 2002

AbstractThis paper presents a method in which moving obstacles such as pedestrians, bicycles, and automobiles are detected from a moving vehicle using images, and the locations of the obstacles are calculated stably in relation to the vehicle. In the proposed method, stereoptic images are projected on the estimated road plane, and a free‐space map is constructed without attempting matching between the stereoptic images. Then, the vanishing point of the motion (FOE) is estimated from the optical flow, and the moving obstacle area is extracted from the image based on the residual error. By projecting the moving obstacle area onto the free‐space map, the location of the moving obstacle relative to the moving vehicle is determined. In this method, neither tracking between frames nor matching search between stereoptic images is needed, and the location can be determined stably, even for objects with rapidly varying size in the image, or nonrigid objects with continuously changing shape. An experiment was performed in which the locations of moving obstacles such as pedestrians, bicycles, and automobiles were determined from the input image sequence obtained from a camera on a moving vehicle. The effectiveness of the proposed method was demonstrated. © 2001 Scripta Technica, Syst Comp Jpn, 32(14): 67–76, 2001
Tree‐based clustering for gaussian mixture HMMs
Authors: Kato Tsuneo , Kuroiwa Shingo , Shimizu Tohru , Higuchi Norio 
Published: August 2002

AbstractTree‐based clustering is an effective method for sharing the state of an HMM in which clustering is applied to a set of context‐dependent models with the phoneme context as the splitting condition. In past papers, the method has been restricted to the single Gaussian HMM. The single Gaussian HMM, however, is insufficient for representing the acoustic features, and an adequate topology (sharing of HMM state) will not necessarily be realized. Furthermore, in order to arrive at a state‐sharing model with the desired number of mixtures, the process of doubling the number of mixtures and the embedded training must be iterated after the tree‐based clustering, which increases the time for training. Consequently, this paper proposes a method in which the tree‐based clustering algorithm for the single Gaussian HMM is extended to the clustering of the mixed Gaussian HMM. The proposed method reduces the training time to approximately one‐third that of the conventional method of handling the single Gaussian HMM. A recognition experiment using a phone typewriter and a recognition experiment for continuous word demonstrate that the recognition rate is improved by one to two points. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(4): 40–49, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1118
Detection of moving objects using observer motion‐based optical flow estimation
Authors: Ebine Takumi , Hamada Nozomu 
Published: August 2002

AbstractA scheme for detecting a moving object in a three‐dimensional environment from observed dynamic images by optical flow, based on the state of the motion of the observing system, is proposed in this paper. The usual optical flow constraint equations defined in an image coordinate system do not sufficiently satisfy the assumptions made in deriving them when the observing system is in motion. In this paper, optical flow constraint equations considering the motion of the observing system are first derived. In order to do this, a mapping converting the motion of a stationary environment image to linear trajectory signals is derived. The uniform velocity property of motion and the isotropic property of motion within a proximal area, which are basic assumptions of the block gradient method, can be satisfied by these. Next, a method of expressing the optical flow constraint equations after mapping by the gradient in the time dimension before mapping is presented. Finally, the residuals of the optical flow constraint equations are proposed as the evaluation quantity for the extraction of a moving object and their efficacy is shown. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(6): 83–92, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1135
A proposal of 2D artificial cellular neural network including nonvolatile unit
Authors: Hiratsu Daisuke , Nagao Tomoharu 
Published: August 2002

AbstractWe have investigated the evolutional optimization of the Artificial Cellular Neural Network (ACNN). ACNN is a kind of neural network model. Neural units in ACNN are placed on a lattice grid, connections in ACNN are allowed only between neighborhood units, and connection weights and threshold parameters can be set independently of other units. In ACNN, connection between far units does not exist. Thus, ACNN architecture is suitable for building as hardware. We have suggested an optimization method of ACNN using a genetic algorithm (GA). In this paper, we introduce the “nonvolatile” attribute into partial units of a 2D ACNN in order to get the ACNN to output suitable data in a certain situation that has a causal relationship with past input. As its exercise, we used Sutton's maze problem, which is well known in the field of reinforcement learning. We prepared a simulation environment in which a 2D ACNN makes decisions of action in Sutton's maze to demonstrate that a 2D ACNN which includes nonvolatile units has better signal processing ability than the usual 2D ACNN. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(7): 40–49, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1140
Improvement of numeral recognition using personal handwriting characteristics based on clustering
Authors: Hotta Yoshinobu , Naoi Satoshi , Suwa Misako 
Published: August 2002

AbstractCorrectly recognizing characters with peculiarities for each writer is a difficult problem. The process of absorbing variations in individual writing by creating an individual dictionary is also difficult when a writer is not specified and the total number of writers is large. In this paper the authors propose a method to improve the results of isolated character recognition in forms in which the same writer writes many characters by taking the characteristics of the writer's writing on a form as a character distribution in a character feature space. In concrete terms, the authors first perform isolated character recognition on all characters on the same form. Then, based on the results of isolated character recognition, clustering of input character groups is performed for each character category. Clusters which are very likely to include misrecognized characters from isolated character recognition are extracted based on the results of clustering. Then character categories in the extracted cluster are automatically amended based on the distance from all clusters in other categories. In the same fashion, automatic amending is performed for rejected characters. Based on experiments to evaluate handwritten numerals on OCR forms, the authors show that the precision of numeral recognition is improved by using this approach as a form of postprocessing for isolated character recognition. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(7): 104–113, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1146
Social and ecological destruction in the first class: a plausible social development scenario
Authors: Kaivo‐oja Jari 
Published: August 2002

AbstractIn a previous issue of Sustainable Development (Kaivo‐oja, 1999) some alternative scenarios of social development were presented. The following scenarios were discussed: (i) the deep ecology scenario, (ii) the strong sustainable development scenario, (iii) the weak sustainable development scenario, (iv) the boomsday scenario, (v) the doomsday scenario and (vi) the World Bank ‘policy tunnel’ scenario. In this article a plausible, seventh social development scenario is presented: ‘social and ecological destruction in the first class’. The basic idea of this scenario is presented in this paper. The author argues that this scenario should also be taken into consideration in the strategic discussion of potential sustainable development paths. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment.
Catalytic cooperation at the interface of physical mixtures of CaO and MgO catalysts during steam gasification of naphthalene
Authors: Alarcón Nelson , García Ximena , Centeno Miguel , Ruiz Patricio , Gordon Alfredo 
Published: August 2002

AbstractOxides CaO, MgO and a physical mixture of 10% CaO + 90% MgO were used as catalysts for the steam gasification of naphthalene. A synergistic effect in the conversion was observed with the mixture. Catalysts were characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and XPS techniques. Basicity was significant for CaO as compared to MgO and the mixture, but did not correlate with catalytic activity. Bidentate carbonate‐type formation, which remained even in the presence of steam at high temperature (1033 K), was observed on CaO. Carbonates on MgO and on the mixture are unidentate and disappeared when steam was present. Formates, carboxylic and aldehydic groups also were formed, at 723 K on MgO and at 423 K on the mixture and on CaO. These species disappeared at 873 and 1033 K for the mixture and CaO, respectively, thus indicating their greater stability on CaO than on the mixture and on the MgO. Deposition of carbonaceous matter on solids was observed. The order of the deposited content is mixture < MgO < CaO. No indication of mutual contamination by the metal composing the oxides was observed. A higher carbonate removal and less carbonaceous matter deposition were observed in CaO when in the mixture, as compared with CaO alone, suggesting a beneficial effect of MgO in the mixture. The synergistic effect observed using the 10% CaO + 90% MgO mixture was related to the inhibition of carbonaceous matter and carbonate formation on the catalysts. This inhibition is due to a catalytic cooperation between both oxides, as two separate phases. The presence of MgO is assumed to avoid the formation of stable bidentate carbonates on CaO, promoting instead unidentate species formation; this facilitates the gasification of naphthalene by steam. Copyright © 2001 John Wiley & Sons, Ltd.
Multivariate image analysis methods applied to XPS imaging data sets
Authors: Artyushkova Kateryna , Fulghum Julia E. 
Published: August 2002

AbstractRecent improvements in imaging photoelectron spectroscopy enhance lateral and vertical characterization of heterogeneous samples at the cost of increasing complexity in the XPS data sets acquired. These imaging data sets require more sophisticated analysis methods than visual inspection if the data are to be interpreted effectively. Multivariate analysis (MVA) methods are increasingly utilized in surface spectroscopies to aid the analyst in interpreting the vast amount of information resulting from these multidimensional data set acquisitions.In this work, image processing analysis methods are tested on XPS data sets acquired from polymer blends. Images from the blends, acquired as a function of composition, time or energy, provide multidimensional data sets for algorithm evaluation. Multivariate image analysis (MIA) methods such as scatter diagrams, principal component analysis (PCA) and classification methods are used to extract maps of pure components from degradation and images‐to‐spectra data sets. In some cases the MVA results can be compared directly with the XPS spectra or images, which provide a critical reference point. This work will demonstrate that additional information can result from the application of MIA methods, even when direct spectral or image interpretation is possible. Copyright © 2002 John Wiley & Sons, Ltd.
Estimation of an errors‐in‐variables regression model when the variances of the measurement errors vary between the observations
Authors: Kulathinal S. B. , Kuulasmaa Kari , Gasbarra Dario 
Published: August 2002

AbstractIt is common in the analysis of aggregate data in epidemiology that the variances of the aggregate observations are available. The analysis of such data leads to a measurement error situation, where the known variances of the measurement errors vary between the observations. Assuming multivariate normal distribution for the ‘true’ observations and normal distributions for the measurement errors, we derive a simple EM algorithm for obtaining maximum likelihood estimates of the parameters of the multivariate normal distributions. The results also facilitate the estimation of regression parameters between the variables as well as the ‘true’ values of the observations. The approach is applied to re‐estimate recent results of the WHO MONICA Project on cardiovascular disease and its risk factors, where the original estimation of the regression coefficients did not adjust for the regression attenuation caused by the measurement errors. Copyright © 2002 John Wiley & Sons, Ltd.