bluuebunny/crossref_metadata_2025_split huggingface dataset:
SIR weighting combining diversity for digital mobile communications
Authors: Maehara Fumiaki , Sasamori Fumihito , Takahata Fumio 
Published: August 2002

AbstractDiversity reception is a powerful technique to reduce the degradation of transmission quality caused by fading. One of the techniques, postdetection maximal‐ratio combiner (MRC), is not necessarily effective under cochannel interference, because received signal strength used as the weighting factor is not relative to the instantaneous signal‐to‐interference power ratio (SIR). The paper proposes an SIR estimation method using the matched filter and a diversity scheme using the estimated SIR as the weighting factor. The performance is evaluated theoretically and by means of computer simulations. The results show that the proposed SIR estimation method can estimate the accurate instantaneous SIR and that the BER characteristics of the proposed diversity scheme under cochannel interference realize better performances than those of MRC. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 85(7): 53–60, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/ecja.1111
Directional difference‐based switching median filters
Authors: Hashimoto Yuuhei , Kajikawa Yoshinobu , Nomura Yasuo 
Published: August 2002

AbstractIn this paper, a new median filter is proposed that has robustness without relying on the noise generation probability. The proposed filter has a configuration with an impulse detector in the prior stage of the filter. Since this detector has a superior signal estimation capability of the directional difference filter, impulse noise can be detected effectively even if generated at a high generating ratio and as a burst. In the median filter in the later stage, inclusion of the output values of the directional filter and successive updating of the signal values (successive process) are introduced. Hence, while the noise elimination capability of the conventional median filter is retained, the signal preservation at the details and edges can be improved. Therefore, the noise elimination filter proposed in this paper is abundant in robustness against variations of the gray scale, the generation probability, and the impulse adding situation. Its restoration results for images with superposed impulse noise at a high generation probability confirm the improvement of performance. In this paper, the effectiveness of the proposed impulse detector is first demonstrated. It is proven through processing examples that a better image processing result can be obtained from its combination with a newly configured median filter. At the same time, the robustness of the proposed procedure under various conditions is demonstrated. The effectiveness of the proposed method in the final restored image is verified. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 85(3): 22–32, 2002
Realization of an orthogonal filter with hypercomplex coefficients
Authors: Okuda Masahiro , Kamata Masato , Takahashi Shin‐ichi 
Published: August 2002

AbstractThis paper proposes an orthogonal digital filter to simultaneously realize a pair of complex‐coefficient digital filters with power complementarity by means of hypercomplex‐coefficient all‐pass digital filters. Hypercomplex filters can realize equivalent characteristics with only half as great a filter order as complex‐coefficient digital filters and only one‐quarter as great an order as real‐coefficient digital filters. A method of realization of the hypercomplex‐coefficient all‐pass transfer function is discussed as well as a method of determining a transfer function with power complementarity for a certain complex‐coefficient digital filter. Further, an example of the hypercomplex‐coefficient transfer function is used and the effectiveness of the proposed method is shown. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 85(3): 52–60, 2002
Modeling and analysis of the NEDO 500‐kW wind generator
Authors: Kodama Naruhito , Matsuzaka Tomoyuki , Yamada Sayosi 
Published: August 2002

AbstractThe 500‐kW wind generator was developed as one of NEDO's projects, and it has been operated at TAPPI wind park since October 1996. Since then, several tests on its performance have been made. One of the most important characteristics concerns the dynamic behavior under fluctuating wind conditions. For this purpose, we performed the modeling of the NEDO 500‐kW wind generator by a system identification technique using the measured data. Next, we clarified the basic characteristics such as transient response and frequency response of the generator based on the model. We confirmed that the simulated results of dynamic behavior almost agree with the measured results. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 37–47, 2001
Noncontact energy transfer system using immittance converter
Authors: Irie Hisaichi , Minami Nobuyuki , Minami Hideaki , Kitayoshi Haruyoshi 
Published: August 2002

AbstractNoncontact energy transfer systems are widely used in industrial material handling systems. This paper proposes a new noncontact energy transfer system using a tuned pickup coil and an immitance converter inductively coupled to a parallel transmission line excited by a high‐frequency constant‐current source.In a noncontact energy transfer system which supplies continuous energy to movers by electromagnetic induction, the efficiency is low owing to low excitation impedance because of the wide air gap of the magnetic core in the pickup coil. The excitation impedance can be increased by the resonance with a capacitor connected parallel to the pickup coil. The resonant pickup coil works as a high‐frequency constant‐current source for the load. We propose using an immittance converter to transform the high‐frequency constant‐current source into a high‐frequency constant‐voltage source. Then, the high‐frequency constant‐voltage source is rectified into a constant‐voltage dc source, and supplies power to an inverter for motor driving.In this paper, the configuration of this new noncontact energy transfer system and its characteristics are described. The experimental results and simulation waveforms are also described. © 2001 Scripta Technica, Electr Eng Jpn, 136(4): 58–64, 2001
Realization of instantaneous torque control of an induction motor considering secondary flux as a parameter
Authors: Hayashi Tomohiro , Fujii Yasumasa , Fujikawa Kiyoshi , Sekiguchi Takashi 
Published: August 2002

AbstractRecently, many researches aiming at the realization of high‐performance and high‐precision control of induction motors have been reported, and instantaneous torque control of an induction motor can be regarded as one of the most important topics in this field. In previous works, the authors developed a new method to realize instantaneous torque control of an induction motor with a voltage‐source inverter, and demonstrated both its numerical simulations and experimental results. Unfortunately, the mathematically complicated derivation of the control method made it difficult to understand intuitively, and hindered us from analyzing the detailed characteristics of motor speed changes.In this paper, the authors propose a new method to realize instantaneous torque control of an induction motor, which differs from the concept of vector control. The proposed method is a two‐degree‐of‐freedom control which considers the instantaneous torque command and secondary flux command as parameters. The analytical solution reported here is a particular solution of the differential state equation of an induction motor, and can be expressed as a simple explicit function of the instantaneous torque command, secondary flux command, and motor speed. The authors show the validity of the proposed method through numerical simulations and experimental results. This paper aims the realization of high‐performance control of an induction motor. The authors propose a new method to realize instantaneous torque control without transient torque with a voltage‐source inverter. © 2001 Scripta Technica, Electr Eng Jpn, 137(1): 48–56, 2001
Instability of a chopper system with input LC filter and its solution
Authors: Tsuboi Katsutaka , Tsuji Mineo , Yamada Eiji 
Published: August 2002

AbstractInstability of propulsion converters with an input LC filter for railway vehicles has already been reported and solutions have been proposed in some applications. However, there are many other systems and circuit topologies for vehicles. In each of these systems, a specific solution is needed. On the other hand, in recent years, with the technical development of breaker apparatus, the series line resistor which limits the short‐circuit current and compensates the interrupting capacity of the line breaker has not been required to have so large a resistance. However, the resistor functioned not only to assist interruption but also to suppress instability. Therefore, instability caused by smaller resistance has become more conceivable, and other solutions and analyses are more urgently needed now. In this paper, this instability of a chopper–inverter system for an air conditioner is analyzed by using the root locus method. It is shown that the cooperative response regulation of controllers or inclusion of the proper dumping circuit is effective in stabilizing the system. The validity of these solutions is confirmed through nonlinear circuit simulations. © 2001 Scripta Technica, Electr Eng Jpn, 137(4): 49–63, 2001
Analysis of magnetically induced ELF current in biological spherical model with biomembrane
Authors: Tarao Hiroo , Hayashi Noriyuki , Isaka Katsuo 
Published: August 2002

AbstractIn this paper a biological three‐medium spherical model which consists of tissue, its membrane, and the extratissue medium is employed, and detailed distributions and characteristics of the induced current in the modeled structure are calculated by using a semianalytical solution developed for this model. It is demonstrated that both the change in the thickness and electrical properties of the biomembrane and the difference in conductivity between the inner and outer substances significantly affect the current passing through the membrane and the resultant profiles of the induced current. These analytical results are consistent with the experimental results, suggesting the influence of real membranes, and they indicate an important influence of the biomembrane on the induced current characteristics under specific membrane conditions. © 2001 Scripta Technica, Electr Eng Jpn, 135(2): 17–25, 2001
Stabilization of power system with TCSDR based on VSS theory
Authors: Wada Harumi , Oyama Tsutomu 
Published: August 2002

AbstractIn order to control a large complex power system, a more flexible decentralized control scheme is desired. Since the system configuration is changing continuously, the system must be controlled based on uncertain and inadequate information. The control scheme should provide robustness.The sliding mode control based on variable structure system theory is regarded as a promising robust control scheme. In this control, the structure of the control system is changed across the hyperplane (switching plane) in state space so that the state variables of the system are kept on the hyperplane.In this paper, applications of sliding mode control to power system stabilization are discussed. The sliding mode control is applied to the control of the thyristor‐controlled SDR (System Damping Resistor). Since the SDR is operated discretely (on or off), it is impossible to keep the state variables on the switching plane all the time. Therefore, “partial” sliding mode control is introduced. A new practical switching plane for sliding mode control is developed. Using the plane, the system can be stabilized effectively. © 2001 Scripta Technica, Electr Eng Jpn, 135(2): 33–42, 2001
Voluntary agreements with emission trading options in climate policy
Authors: Albrecht Johan , François Delphine 
Published: August 2002

AbstractRecent political and corporate initiatives indicate that voluntary agreements and emission trading will play a crucial role in climate policy. We show that when emission trading is integrated as an option in voluntary agreement contracts, the overall efficiency of the use of flexible climate policy instruments is strongly increased. The emission trading option, formalized as a CO2 allowance call option contract that can be traded, provides clear incentives to overcomply with the target of the voluntary agreement. The option mechanism also delivers a market price for eventual non‐compliance, based on differences in abatement costs. With an example, we illustrate that the option mechanism can result in stimulating financial benefits for the firms that are most successful in reducing emissions. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
The cost of spatial management
Authors: Schou Jesper S. , Birr‐Pedersen Katja 
Published: August 2002

AbstractThe spatial dimension of agri‐environmental analysis has been recognized in a large number of studies, and the implications for the choice of analytical approaches and, further, environmental policies have been investigated both theoretically and empirically. Spatial management is an integrated part of Danish legislation, which, especially, is manifested in the land use policies. In this paper we analyse the opportunity costs of spatial management, as the costs of two strategies for establishing 400 ha of forest on existing agricultural land are assessed. The first ‘planning’ strategy involves establishment of the forest in afforestation zones designated by the local county based on the criteria of vicinity to cities and existing forest. The second strategy involves selecting afforestation areas based on a cost‐minimizing approach using spatial variations in farm economic output in the study area. Results suggest that the opportunity costs of the planning strategy are 2.5 times higher than of the cost‐minimizing strategy, indicating that the additional benefits of the planning strategy need to be significant in order to justify choosing this management approach. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
2‐Amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP)–induced mutagenesis in cultured Big Blue™ rat mammary epithelial and fibroblast cells
Authors: McDiarmid Heather M. , Douglas George R. , Coomber Brenda L. , Josephy P. David 
Published: August 2002

AbstractEpithelial cells are the primary site of carcinogenesis in most tissues, including the mammary gland. As an alternative to the study of mutation induction in whole tissues in vivo, we have established Big Blue™ transgenic rat cell lines from the mammary epithelium (BBR/ME) and the mammary stroma (BBR/MFib), to permit a comparison of their mutagenic responses to carcinogens. We previously demonstrated their responsiveness to the alkylating agent N‐ethyl‐N‐nitrosourea (ENU) (McDiarmid H et al. [2001]: Mutat Res 497:39–47). Here, we examined the responses of cultured epithelial and stromal cells to the protein pyrolysis product and mammary carcinogen 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP). Rat hepatic S9 was used as a source of bioactivation enzymes. Mutant induction (cII locus) and clonogenic survival were measured as a function of PhIP concentration. PhIP mutagenicity was observed in the fibroblast cells, but the greater toxicity of PhIP to the epithelial cells prevented a definitive evaluation of mutagenicity. Since PhIP may be detoxified by conjugation with glutathione, we measured glutathione levels and glutathione‐S‐transferase expression and activities in both cell lines. The epithelial cells had higher glutathione‐S‐transferase enzyme activity and protein expression than did the fibroblast cell line. Because the epithelial cells were more sensitive to toxicity, glutathione conjugation evidently plays only a minor role in PhIP toxicity and mutagenicity in our cell lines. Environ. Mol. Mutagen. 39:245–253, 2002. © 2002 Wiley‐Liss, Inc.
A single (6‐4) photoproduct inhibits plasmid DNA replication in xeroderma pigmentosum variant cell extracts
Authors: Yao Jiaqin , Dixon Kathleen , Carty Michael P. 
Published: August 2002

AbstractThe human skin cancer‐prone disease xeroderma pigmentosum variant (XPV) results from a mutation in the human RAD30 gene, which encodes the lesion bypass DNA polymerase η. XPV cells are characterized by delayed completion of DNA replication and increased mutagenesis following UV‐irradiation. Using extracts of an XPV lymphoblast cell line (GM2449C) that has a truncating mutation in the RAD30 gene, we investigated the effect of a (6‐4) photoproduct and a cyclobutane pyrimidine dimer (CPD), at a unique –TT– site on either the leading or lagging strand, on plasmid DNA replication. Compared to normal cell extracts, XPV cell extracts have a reduced capacity to carry out complete replication of DNA containing either a (6‐4) photoproduct or a CPD on the leading strand, whereas there is little difference between the two cell extracts in replication of DNA containing a lesion on the lagging strand. Inhibition of replication in the presence of a (6‐4) photoproduct is attributed to arrest of nascent DNA strand synthesis at the lesion site; in XPV cell extracts, the proportion of arrested products is increased compared to that of normal cell extracts. These results are consistent with a requirement for functional DNA polymerase η in the replication of a double‐stranded plasmid containing either a (6‐4) photoproduct or a CPD, on the leading but not the lagging strand. Environ. Mol. Mutagen. 38:19–29, 2001 © 2001 Wiley‐Liss, Inc.
Debates over environmental information to stakeholders as a policy instrument
Authors: Synnestvedt Terje 
Published: August 2002

AbstractThis paper concerns the provision of environmental information as an environmental policy tool. Corporate environmental information is often hard to obtain and in general not suited for comparison in time and space. This combined with the need for improved environmental performance raises the question of whether mandatory information schemes could be a powerful tool within environmental regulation. The power definitely depends on how the disclosure scheme affects managers' and stakeholders' behaviour. A number of factors, such as the extent of environmental impacts of the industry, the degree of competition in the industry, the cost of improving environmental performance and customer characteristics, probably create differences in managers' responses to mandatory disclosure. This implies different needs for mandatory disclosure with respect to both quality and quantity. One conclusion drawn from the discussion is that focus probably should be drawn towards the quality of information rather than the quantity, especially for large firms. Copyright © 2001 John Wiley & Sons, Ltd. and ERP Environment
A new proposal for simplified design of buried steel pipes crossing active faults
Authors: Takada Shiro , Hassani Nemat , Fukuda Katsumi 
Published: August 2002

AbstractSimplified design methods for obtaining the maximum strain in pipelines crossing active faults proposed by Newmark, Kennedy and Wang have not considered the section deformation of the pipe. In this study, a new simplified method is developed for obtaining the maximum strain in steel pipes crossing faults considering non‐linearity of material and geometry of pipe section. It is assumed that the pipe will bend near the fault and the geometry of pipe in the longitudinal direction will change according to a bent deformation. On the other hand, the relation between maximum strain and bent angle has been obtained using a beam–shell hybrid FEM for different pipe‐fault conditions. The developed method can be used for calculating the maximum strains for fault‐crossing steel pipes with different angles of crossing both in tension and compression, by considering the deformation of the pipe cross‐section. Copyright © 2001 John Wiley Sons, Ltd.
On‐line identification of non‐linear hysteretic structural systems using a variable trace approach
Authors: Lin Jeng‐Wen , Betti Raimondo , Smyth Andrew W. , Longman Richard W. 
Published: August 2002

AbstractIn this paper, an adaptive on‐line parametric identification algorithm based on the variable trace approach is presented for the identification of non‐linear hysteretic structures. At each time step, this recursive least‐square‐based algorithm upgrades the diagonal elements of the adaptation gain matrix by comparing the values of estimated parameters between two consecutive time steps. Such an approach will enforce a smooth convergence of the parameter values, a fast tracking of the parameter changes and will remain adaptive as time progresses. The effectiveness and efficiency of the proposed algorithm is shown by considering the effects of excitation amplitude, of the measurement units, of larger sampling time interval and of measurement noise. The cases of exact‐, under‐, over‐parameterization of the structural model have been analysed. The proposed algorithm is also quite effective in identifying time‐varying structural parameters to simulate cumulative damage in structural systems. Copyright © 2001 John Wiley & Sons, Ltd.
Screening tests for fire safety of composites for marine applications
Authors: Sorathia U. , Long G. , Gracik T. , Blum M. , Ness J. 
Published: August 2002

AbstractDemands for reduced maintenance, reduced manning and reduced cost are resulting in the need for new and alternative materials for introduction in the fleet. The new materials in many cases tend to be non‐metallic and organic (combustible) materials. In order to maintain a minimum level of fire safety, the US Navy has set performance requirements for new materials in many applications. These include the use of composite materials in ships and submarines. Performance requirements for composites, in most cases, are based on full‐scale fire tests. The use of composites for structural applications in submarines is covered by MIL‐STD‐2031. The use of composites aboard US Navy ships for topside applications is now covered by Fire Safety testing criteria. The recommended fire performance criteria contain requirements for fire growth, smoke toxicity, visibility (ISO 9705), fire resistance and structural integrity under fire (UL 1709). When developing new composite systems, it is expensive to repeatedly conduct these typical full‐scale fire tests to determine the performance of the most recent design. Instead, more cost‐effective small‐scale testing is preferable to evaluate performance. To facilitate the introduction of new and modified fire tolerant materials/systems/designs, and to reduce the financial burden on small business, the US Navy has developed a low cost composite system fire screening protocol which offers the potential of predicting the full‐scale fire performance. Fire growth potential of new composite systems and designs can be screened by using small‐scale test data from cone calorimeter (ASTM E‐1354) and Lateral Ignition Flame spread Test (ASTM E‐1321) in conjunction with the Composite Fire Hazard Analysis Tool (CFHAT). The small‐scale burn‐through test (2×2 ft) was shown capable of screening fire resistance performance determined in furnace testing with a UL‐1709 fire curve. These screening techniques provide cost‐effective approaches for evaluating fire performance of new technologies, which in turn aids in the product development process. Full‐scale fire testing is still required before inclusion of products onboard US Navy submarines and surface ships. Published in 2002 by John Wiley & Sons, Ltd.