bluuebunny/crossref_metadata_2025_split huggingface dataset:
Slot array antenna for wireless LANs with backward excitation
Authors: Yamamoto Manabu , Ishizaki Kosuke , Muramoto Mitsuru , Sasaki Kanemi , Itoh Kiyohiko 
Published: August 2002

AbstractAttention is directed to the slot array antenna that is serially fed by a microstrip line and a method is studied for using this antenna as a constituent element of a planar multisector antenna for wireless LAN. Based on the design ignoring the mutual coupling between the slots, an excitation method for realization of a beam tilt toward the endfire direction is investigated. It is found that backward excitation is effective. The antenna is modeled by the spectral domain moment method and a design is carried out by taking into account the mutual coupling. Further, by test measurement, the validity of the modeling and the effectiveness of the proposed design method are confirmed. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(9): 59–68, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1126
Target tracking with adaptive sampling intervals using a phased array radar
Authors: Yanbe Akio , Ito Masayoshi , Tsujimichi Shingo , Kosuge Yoshio 
Published: August 2002

AbstractThe phased array antenna can instantaneously direct a radar beam into a desired direction without mechanically moving the antenna. Anticipating an application to a phased array radar, adaptive control of the sampling interval for the tracking object is considered. Reducing the sampling interval for a target with high maneuverability prevents degradation of the tracking accuracy. For a target in straight‐line motion, the sampling interval is increased so that the number of observations is reduced for an efficient operation of radar resources. In this paper, the M3(Multiple Maneuver Model) filter is used as one of the tracking algorithms based on the multiple motion model, and a control scheme is proposed with a sampling interval based on the tracking error covariance matrix. By means of simulation, the tracking performance is compared with the case where the sampling interval is fixed. As a result, the tracking accuracy is improved by 15% during a maneuvering motion without increasing radar resources. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(10): 44–54, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1130
An efficient method to search for the location of network services with multiple QoSs guarantee
Authors: Kawano Keita , Masuda Tomokazu , Kinoshita Kazuhiko , Murakami Koso 
Published: August 2002

AbstractFor future multimedia communication networks, it is an essential element to guarantee multiple QoSs so that users have satisfactory services. Thus, recently, many QoS routing algorithms have been proposed. However, they merely select a point‐to‐point path which has sufficient resources for the request for QoSs. Therefore, it is difficult to search for the location of the service which is provided according to their request and to select a feasible path from the service provider to the originating node by QoS routing alone. Furthermore, for multimedia communications, there are many service providers which provide the same service content, and each of them attaches individual QoS values to their service content. There are, however, few studies of methods to search for the location of services which are provided with these QoSs. Therefore, in this paper, a new method to search for the location of services with multiple QoS guarantee is proposed. It allows fast searching by utilizing the link state. Finally, we show by simulation experiments that the proposed method has good performance. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(10): 55–63, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1131
Distinctive features of thin‐layer sealed lead‐acid storage batteries with comb‐shaped plates
Authors: Horie Toshio , Takahashi Minoru , Ogata Tsutomu , Hirai Toshiro 
Published: August 2002

AbstractWe fabricated 2.5‐mm thick lead‐acid cells with comb‐shaped electrodes, sealed with laminated sheets, and estimated their performance. Some of the cells showed above 500 mAh of an initial capacity and one of them were cycled over 140 times till the capacity decreased to a half of the initial capacity. The initial capacity was affected strongly by viscosity of electrolyte gel filled in the cells. Utilization of electrode active materials and electrolyte was more than 20% and 55%, respectively, in the cells showed above 500 mAh of initial capacity. Cycle life was influenced mainly by cathode degradation and electrolyte drying out. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(11): 60–67, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1138
Acquiring the ability of object localization by vision and audition through motion
Authors: Asai Yasuyuki , Nakashima Hiromichi , Yamamura Tsuyoshi , Huang Jie , Ohnishi Noboru 
Published: August 2002

AbstractThis paper proposes a sound source localization learning model based on iterated perception by vision and audition through neck rotation. Learning is performed through object localization by vision and audition with motion. The model is composed of three multilayered perceptron‐type neural networks. The error signal to be used in the learning by error backpropagation is acquired by motion. The learning process is as follows. For each generation of sound, four actions are performed: auditory localization, visual localization, search, and step centering. The learning is based on the acquired information. In order to verify the validity of the proposed model, a computer simulation experiment and an experiment using a robot and a real sound source were performed. The experiments demonstrated that auditory and visual localization are performed simultaneously. Generalization of the unlearned direction and efficient operation are also demonstrated. The localization error is examined as a function of the distance between the source and the robot. The mapping by the neural network after learning is also investigated. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(4): 58–67, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10046
Investigation of new‐mode‐type SAWs by procedures combined with finite‐element and analytical method, and their applications for devices used in mobile communications
Authors: Isobe Atsushi , Hikita Mitsutaka , Asai Kengo , Sumioka Atsushi 
Published: August 2002

AbstractSimulations using a combination of the finite‐element method and the analytical method as well as experiments are used to study new‐mode‐type SAWs. First, in 171°YZé‐LiNbO3, it is found that there exists a longitudinal leaky SAW with a high acoustic velocity and a high Q in a grating structure with an Al film thickness of 0.084 wavelength. The acoustic velocity is 6100 to 6500 m/s and the Q values are more than 4000 (computed) at both the resonance and antiresonance points. These excellent properties are suitable for high‐frequency SAW devices. Next, in 15°YX‐LiNbO3, it is found that there exists a grating mode SAW of a transverse wave type in a grating structure with an Al film thickness of 0.125 wavelength. In this case,k2has an extremely large value of 28.5% and hence the mode is suitable for a SAW resonator for use in a voltage‐controlled oscillator. By means of this SAW, SAW‐VCOs at 400 and 170 MHz for mobile communication are fabricated. At 400 MHz, the frequency variable width is 54 MHz (3.2%/V) and the phase noise is less than –115 dBc/Hz at 25 kHz; the corresponding values at 170 MHz are 24 MHz (3.4%/V) and < –12 dBc/Hz at 25 kHz. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(4): 49–58, 2001
Design of low‐delay perfect‐reconstruction filter banks using linear programming
Authors: Ota Morihiko , Higa Yoshito , Ochii Hiroshi 
Published: August 2002

AbstractIn many applications of filter banks, a low‐delay filter bank in which the system delay is small is desirable. In this paper, two new design methods are proposed for low‐delay perfect‐reconstruction filter banks. First, a design method is described for a two‐channel perfect‐reconstruction filter bank suitable for subband coding. In this method, a high‐pass filter for perfect reconstruction is designed for an arbitrary low‐pass filter. Next, a design method is described for an oversampling perfect‐reconstruction DFT filter bank suitable for subband adaptive filter. In this method, a prototype filter for a perfect‐reconstruction synthesizer is designed for the prototype filter for an arbitrary analyzer. The effectiveness of the present method is demonstrated by design examples. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(6): 30–39, 2001
Production of transparent conductive films with inserted SiO2anchor layer, and application to a resistive touch panel
Authors: Noda Kazuhiro , Tanimura Kohtaro 
Published: August 2002

AbstractIn order to reduce light reflectivity and enhance the durability of resistive touch panels used for pen input, a transparent conductive film consisting of an inserted SiO2anchor layer between PET and ITO layers (ITO/SiO2/PET) was produced and its application to resistive touch panels was attempted.The luminous reflectance of the ITO/SiO2/PET structure was found to be about 4% lower than that of ITO/PET. The durability was estimated by the resistance change ratio of the ITO layer caused by damage due to scribbling; the decrease in resistance of the ITO/SiO2/PET structure was less than half that of the ITO/PET structure. Furthermore, the resistivity of the ITO layer in ITO/SiO2/PET was 8.4 × 10–4Ω‐cm, lower than the value of 1.3 × 10–3Ω‐cm in ITO/PET. This demonstrates the conductivity‐increasing effect of the insertion of a SiO2layer into the transparent conductive film. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 84(7): 39–45, 2001
Plane‐Type Fiberoptic Switches
Authors: Horino Masaya , Sato Kazutaka , Hayashi Yukio , Mita Masahiro , Nishiyama Toshikazu 
Published: August 2002

AbstractThe optical switch is an essential and indispensable optical device in improving reliability and developing advanced functions in optical communications systems and occupies an extremely important position in the development of optical communications technology. With the objective of developing a mechanical optical switch having a compact, low‐loss, simple assembly, new optical switches that mechanically move the optical fibers have been devised and subjected to various investigations. In this paper, we describe the operating principle and the assembly process of an optical switch and examine its basic characteristics as an optical switch by using a prototype. From the results, we found that the latching can be switched by using an electromagnetic actuator that combines a permanent magnet and coils. In addition, an insertion loss below 1 dB and a return loss of nearly 50 dB were obtained. Furthermore, a continuous switching test was performed and optical switching was possible after 10,000,000 operations. © 2001 Scripta Technica, Electron Comm Jpn Pt 2, 85(1): 41–49, 2002
Transient analysis of lossy nonuniform transmission line using the finite difference time domain method
Authors: Sekine Toshikazu , Kobayashi Kunikatsu , Yokokawa Senji 
Published: August 2002

AbstractWith a view to carrying out a highly accurate and fast time domain analysis of a lossy nonuniform transmission line, a method is described for application of the FDTD method to a finitely long lossy nonuniform transmission line. The present method is applied to a parabolic transmission line as one variety of nonuniform transmission line and a step response analysis is performed. By comparison with an analytical solution and other methods, the effectiveness of the method is confirmed. Also, the step response at the output end of a lossy nonuniform transmission line is almost a step waveform under conditions different from the distortionless transmission condition of a uniform line. Based on this result, a method is described for approximating the step response waveform at the output end of a lossy parabolic line to a step waveform. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 85(8): 1–10, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10006
Blind deconvolution of blurred images by use of ICA
Authors: Umeyama Shinji 
Published: August 2002

AbstractIndependent Component Analysis is a new data analysis method, and its computation algorithms and applications have been widely studied recently. Most applications, however, are in the field of one‐dimensional data analysis, such as sound data analysis, and few applications for two‐dimensional data (e.g., image data) have been studied. In this paper, a new application of ICA for two‐dimensional data analysis is given, namely, image restoration of blurred images. The proposed method can restore the original image without knowing the blurring process. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 84(12): 1–9, 2001
Packing of L‐shaped and rectangular modules using sequence‐pair method
Authors: Fujiyoshi Kunihiro , Murata Hiroshi 
Published: August 2002

AbstractRectangle packing is a critical problem in applications such as placement in VLSI layouts. Recently, the sequence‐pair method was proposed as a representation method for rectangle packing where the general configuration is not restricted to the slice configuration. This method has led to a variety of research on applications because of its feature of packing all sequence‐pairs in addition to the ability to represent any kind of packing. In this paper, we propose a method that uses the sequence‐pair to represent packing L‐shaped modules and not only rectangular modules. Then we propose an algorithm to obtain the total number of modules,n, inO(n3) time in the densest packing in “packing that restored all of the L‐shaped modules while obeying the horizontal and vertical constraints imposed by the given sequence‐pair.” Furthermore, the necessary and sufficient conditions for packing the given sequence‐pair and the proofs are given. These necessary and sufficient conditions are not related to the module size and depend only on the sequence‐pair. Finally, the effectiveness of the proposed algorithm is demonstrated from test results. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 85(2): 52–64, 2002
Influence of surface roughness on the charging of insulating spacers in vacuum
Authors: Yamamoto Osamu , Takuma Tadasu , Hamada Shoji , Kakehashi Yasuhiro , Ikoma Shingo , Nishimura Kouichi , Shioiri Tetsu 
Published: August 2002

AbstractThis paper describes the charging phenomena of cylindrical insulators made of PMMA, PTFE, or Al2O3under ramped and stepped dc voltage. It is primarily concerned with the influence of surface roughness on the formation of charging for various insulating spacers. By using an electrostatic probe located on the cathode, we conducted real‐time observations of the electric field induced by the surface charge. It was found that the surface roughness positively affects the charging, which becomes more pronounced in insulators polished to a higher degree. Furthermore, polished insulators are characterized by a shorter time lag. These results show the importance of surface treatment for insulating spacers in vacuum. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 16–25, 2001
Fluctuation analysis of partial discharge pulse occurrence with an integral equation
Authors: Okamoto Tatsuki , Kato Takeyoshi , Yokomizu Yasunobu , Suzuoki Yasuo 
Published: August 2002

AbstractThis paper proposes an integral equation to describe the stochastic fluctuation of partial discharge (PD) occurrence under sinusoidal voltage stress based on a simple PD model. In the model, the stochastic behavior of PD fluctuation is assumed to arise from the fluctuation of the PD delay time after the inception voltage is built up across a discharge gap. For simplicity of calculation, the delay time is assumed to have an exponential distribution. Based on these assumptions, it is found that the proposed integral equation provides the basic characteristics such as the PD pulse distribution in the applied voltage phase angle domain. The authors have solved the equation numerically and demonstrate several ϕ–ndistribution patterns with average delay times of 0.05 to 5 ms at low applied voltage. The solution is compared with PD characteristics obtained by Monte Carlo simulation based on the same PD model, and good agreement is found. © 2001 Scripta Technica, Electr Eng Jpn, 136(1): 16–28, 2001
Some suggestions for regional industrial ecosystems – extended industrial ecology
Authors: Korhonen Jouni 
Published: August 2002

AbstractIndustrial ecology (IE) is an emerging concept from industrial environmental management arising from a provocative ecosystem analogy of recycling orroundputsystems. The systems approach in the concept, i.e. to facilitate the emergence of entire industrial systems based on cooperation in waste material and energy utilization between the actors involved in the system, has been applied in only a few case studies. These have been conducted with regional industrial systems. In this paper the ecosystem analogy in IE is extended to include also the three other basic principles or metaphors of system development of ecosystems besides roundput: diversity, locality and gradual change. The four ecosystem metaphors constitute theextended industrial ecologyapproach, in which the metaphors are considered in industrial systems. An example of a regional industrial ecology study with the Jyväskylä industrial ecosystem is considered with the thesis. Some initial suggestions for developing the extended industrial ecology approach are presented. Copyright © 2001 John Wiley & Sons, Ltd. and ERP Environment
One size doesn't fit all: estimating environmental Kuznets curves for hazardous waste site counts
Authors: Bohara Alok K. , Berrens Robert P. , Gawande Kishore , Wang Pingo 
Published: August 2002

AbstractAn emergent empirical literature demonstrates theenvironmental Kuznets curve(EKC), or inverted‐U relationship, between environmental pollution and per capita income. Results are controversial and open to a variety of interpretations. The first contribution of this paper is to extend the limited empirical evidence of the EKC relationship to an unexpected context – counts of hazardous waste sites across U.S. counties. However, the primary contribution of this paper is methodological. By applying the EM algorithm, and the latent class Poisson model, to heterogeneous count data we employ an innovative technique for investigating EKC results. This approach allows us to identify three latent classes all exhibiting the inverted‐U relationship but with distinct characteristics. Hence one size doesn't fit all, and we find that three EKCs are required to adequately fit the data. One potential implication is that environmental policy should be designed differentially for these different classes. In particular, it may need to be geographically targeted for the efficient cleanup of blighted urban areas. Finally, future EKC studies should evaluate the potential for multiple curves. Copyright © 2001 John Wiley & Sons, Ltd.
Use of Bayesian dynamic models for updating estimates of contaminated material
Authors: Gargoum A. S. 
Published: August 2002

AbstractExperienced personnel and safety engineers have a great deal of expertise about the profile of the future emission of contaminated mass from the source after an accident (nuclear, chemical, …). This expert judgement, some quantitative and some qualitative, would be available from the time of the initial release (prior information) and can be accommodated into Bayesian uncertainty management in dispersal models such as puff models. To make full use of this expertise, we outline how prior qualitative information about the expected development of the emission can be modeled as a dynamic linear model (DLM). This prediction model will be used to provide estimates of the source term along with associated uncertainties. Details of matching expert judgement and expected emission profiles are discussed. Copyright © 2001 John Wiley & Sons, Ltd.
Performance of partial Mann–Kendall tests for trend detection in the presence of covariates
Authors: Libiseller Claudia , Grimvall Anders 
Published: August 2002

AbstractTrend analyses of time series of environmental data are often carried out to assess the human impact on the environment under the influence of natural fluctuations in temperature, precipitation, and other factors that may affect the studied response variable. We examine the performance of partial Mann–Kendall (PMK) tests, i.e. trend tests in which the critical region is determined by the conditional distribution of one Mann‐Kendall (MK) statistic for monotone trend, given a set of other MK statistics. In particular, we examine the impact of incorporating information regarding covariates in the Hirsch–Slack test for trends in serially correlated data collected over several seasons. Monte Carlo simulation of the performance of PMK tests demonstrates that the gain in power due to incorporation of relevant covariates can be large compared to the loss in power caused by irrelevant covariates. Furthermore, we have found that the asymptotic normality of the test statistics in such tests enables rapid and reliable determination of critical regions, unless the sample size is very small (n < 10) or the different MK statistics are very strongly correlated. A case study of water quality trends shows that PMK tests can detect and correct for rather complex relationships between river water quality and water discharge. The generic character of the PMK tests makes them particularly useful for scanning large sets of data for temporal trends. Copyright © 2002 John Wiley & Sons, Ltd.
Non‐parametric confidence intervals for correlations in nearest‐neighbour Markov point processes
Authors: Pallini Andrea 
Published: August 2002

AbstractWe study bootstrap confidence intervals for correlation functions in nearest‐neighbour Markov point processes, where the neighbours are characterized by an interaction of bounded radiusr. In forestry statistics, the points are tree locations belonging to a region (forest) A, and the marks are qualitative or quantitative tree variables, such as tree species, the stem diameter, crown length or tree height. Estimating and analysing correlation functions between locations and marks, cross‐correlations between different species and their marks, is typically a key step in statistical interpretation of mapped data sets from a forest stand. In order to define the original sample, we propose coding schemes, which are fixed and divide the observed region A of the point process into regular, conditionally independent subregions {Bυ} located at Euclidean distanced ≥ 2r. Bootstrap confidence intervals are then obtained directly, by considering kernel density estimates from all subregions {Bυ} as conditionally independent replicates. Copyright © 2002 John Wiley & Sons, Ltd.