bluuebunny/crossref_metadata_2025_split huggingface dataset:
QoS routing through alternate paths in wirelessad hocnetworks
Authors: Zhang Baoxian , T. Mouftah Hussein 
Published: April 2004

AbstractQuality of service (QoS) routing plays an important role in QoS provisioning for mobilead hocnetworks. This work studies the issue of route selection subject to QoS constraint(s). Our method searches for alternate routes with satisfied QoS requirement(s) to accommodate each communication request when the shortest path connecting the source–destination pair of the request is not qualified. In order to effectively reduce protocol overhead, a directed search mechanism is designed to limit the breadth of the searching scope, which aims at achieving a graceful tradeoff between the success probability in QoS route acquisition and communication overhead. Efficient hop‐by‐hop routing protocols are designed for route selection subject to delay and bandwidth constraint, respectively. Simulation results show that the designed protocols can achieve high performance in acquiring QoS paths and in efficient resource utilization with low control overhead. Copyright © 2004 John Wiley & Sons, Ltd.
The hopcount to an anycast group
Authors: Mieghem Piet Van 
Published: April 2004

AbstractThe probability density function of the number of hops to the most nearby member of the anycast group consisting of m members (e.g. servers) is analysed. The results are applied to compute a performance measure η of the efficiency of anycast over unicast and to the server placement problem. The server placement problem asks for the number of (replicated) servers m needed such that any user in the network is not more than j hops away from a server of the anycast group with a certain prescribed probability. Two types of shortest path trees are investigated: the regular k‐ary tree and the irregular uniform recursive tree. Since these two types of trees indicate that the performance measure η ≈ 1 − a log m where the real number a depends on the details of the tree, it suggests that for trees in real networks (as the Internet) a same logarithmic law applies. An order calculus on exponentially growing tree further supplies evidence for the conjecture that η ≈ 1 − a log m for small m. Copyright © 2004 John Wiley & Sons, Ltd.
Modelling multi‐dimensional QoS: some fundamental constraints
Authors: Liu Nelson X. , S. Baras John 
Published: April 2004

AbstractIn this paper, we model multi‐dimensional QoS in a unified framework, and study some fundamental constraints from the network and the traffic on realizing multiple QoS goals. Multi‐dimensional QoS requirements are quantitatively represented using a QoS region. Based on the theory of effective bandwidths, the framework connects the throughput, the delay, and the loss rate in a uniform formula. Important traffic and network factors, namely, the burst size and the link speed, are involved. With this framework, it is found that the burst size sets hard limit on the QoS region that can be achieved, and that the matching between the link speed and the node processing power can greatly improve the limit. It is also made clear that while pure load imbalance among links does not affect the QoS region, the heterogeneities of burst size or link speed may severely degrade the QoS performance. Applying the theory to real‐time services in differentiated services architecture, we show it provides a useful tool for QoS prediction and network dimensioning. Copyright © 2004 John Wiley & Sons, Ltd.
Optimal design method for selective nerve stimulation
Authors: Kajimoto Hiroyuki , Kawakami Naoki , Tachi Susumu 
Published: April 2004

AbstractThis paper discusses selective stimulation, which is a problem common to various electrical stimulation techniques. The induction of nerve activity by electrical stimulation is a technique which is widely used in medical and health care. In order to reduce unpleasant feelings during stimulation and to diversify the induced sensations, it is necessary to control the stimulus waveform and to design the electrode in appropriate ways. From the viewpoint of nerve stimulation, the above requirement can be interpreted as a selective stimulation problem in which the target nerve fiber is stimulated and the activities of other nerves are minimized. At the present stage of electrical stimulation, however, there is no means of representing selectivity of stimulation mathematically, although precise modeling of the stimulus site is possible. Consequently, the design for selective stimulation is based on trial and error. The purpose of this paper is to construct a mathematical framework for the design of selective stimulation. The requirement for selective stimulation is formulated as a quadratic programming problem which gives a route to the optimal stimulation technique. Several simple examples are solved, and the usefulness of the proposed method is shown through comparison to selective stimulation techniques that were proposed in the past. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 62–72, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20098
Machine translation method using inductive learning for mobile terminal
Authors: Matsuhara Masafumi , Araki Kenji , Tochinai Koji 
Published: April 2004

AbstractThe authors propose a machine translation technique for a compact terminal such as a mobile telephone. With a compact terminal that emphasizes portability such as a mobile phone, the number of keys that the terminal can be equipped with is necessarily restricted by the limited size of the terminal itself. Therefore, to enable input by using only this small number of keys, the proposed technique assigns multiple characters to a single input key. In addition, to enable rapid input, a single character is entered by a single key‐press. As a result, the number sequence that is the input string to the proposed technique is associated with multiple character strings, and thus there also exist multiple translation candidates for this number sequence, thereby increasing ambiguity. Nevertheless, by using inductive learning, the proposed technique can automatically acquire translation rules that depend on the subject and use these rules for translation. This high level of adaptability enables the proposed technique to eliminate ambiguity as much as possible during the translation process to obtain a correct translation. The authors created a system based on the proposed technique and assigned a small number of word translation rules in advance to perform Japanese‐to‐English machine translation experiments. The results verified the effectiveness of the proposed technique by showing that the final translation precision of approximately 70% and the translation efficiency were high. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 33–47, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20100
Space charge distribution for various glass materials under DC stress
Authors: Miyake Hiroaki , Ito Yuuki , Tanaka Yasuhiro , Takada Tatsuo , Hanai Masahiro 
Published: April 2004

AbstractSpace charge accumulation for various glass materials under DC stress was studied by using a pulse electroacoustic (PEA) method. We should make an acoustic matching between the sample and electron on the high‐voltage side when the hetero‐space charge distribution in glass materials is measured. The acoustic pressure wave generated from the induced charge at the high‐voltage side is canceled by the reflected one generated from hetero‐charge accumulated in the sample. Large hetero‐charge is observed in the glass materials containing MgO and CaO compound compared to the quartz glass containing no such compounds. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 19–27, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10260
A study of capacitive current switching capability by flashover characteristics between contacts of circuit breakers
Authors: Toyoda Mitsuru , Aoyagi Hirokuni , Mizoguchi Hitoshi 
Published: April 2004

AbstractThis paper describes the capacitive current interruption capability of circuit breakers from the viewpoint of flashover characteristics between the contacts of breakers. The authors obtained flashover characteristics between the contacts having a short gap between them by comparing the data for new contacts and the data for contacts eroded after having been exposed to three interruptions at T60 according to amended regulations JEC 2300 (1998) and IEC 62271‐100 (2001). Comparison of the flashover characteristics and the electric field calculations obtained by measurements using new and eroded contacts have shown that the deterioration of dielectric strength amounts to 10 to 20%. The authors also conducted flashover tests for the contacts and nozzle after a significant number of interruptions. The total number of interruptions can be considered as the maximum possible number of interruptions according to CIGRE research. The deterioration of dielectric characteristics is 10 to 30%. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 28–37, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10281
Robustness of the multigrid method for edge‐based finite element analysis
Authors: Watanabe Kota , Igarashi Hajime , Honma Toshihisa 
Published: April 2004

AbstractThe dependence of the multigrid finite element method solving three‐dimensional magnetostatic fields on the quality of the finite element mesh is reported. It is shown that the convergence of the multigrid method is strongly influenced by the mesh quality. Moreover, the multigrid method with ICCG smoother is shown to be more robust against mesh distortion than that with Gauss–Seidel and SOR smoothers. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 75–81, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10289
A highly efficient contactless electrical energy transmission system
Authors: Ayano Hideki , Nagase Hiroshi , Inaba Hiromi 
Published: April 2004

AbstractThis paper proposes a new concept for contactless electrical energy transmission system for an elevator and an automated guided vehicle. The system has rechargeable batteries on the car and electrical energy is supplied at a specific place. When electric power is supplied to the car, it runs automatically and approaches the battery charger. Therefore, a comparatively large gap is needed between the primary transformer at the battery charger and the secondary transformer on the car in order to prevent damage which would be caused by a collision. In this case, a drop of the transformer coupling rate due to the large gap must be prevented. In conventional contactless electrical energy transmission technology, since electric power is received by a pickup coil from a power line, a large‐sized transformer is required. When the distance over which the car runs is long, the copper loss of the line also increases. The developed system adopts a high‐frequency inverter using a soft switching method to miniaturize the transformer. The system has a coupling rate of 0.88 for a transformer gap length of 10 mm and can operate at 91% efficiency. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 66–74, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10290
Position control for a linear slider with twin linear drives
Authors: Nakashima Ray , Hao Shuanghui , Honda Hideki , Oguro Ryuichi , Miyakawa Hidekazu , Tsuji Teruo 
Published: April 2004

AbstractIn this paper, position control of a linear slider with twin linear drives is considered. Recently, for high‐speed response, several linear motors have been used for linear slider systems.In such a linear slider, if the linear drives are controlled individually, their position responses may undergo vibrational disturbance by interaction with the output of the motors. To control this vibration, this paper presents a dynamic model of a linear slider system which consists of two motion systems decoupled by coordinate transformation, and proposes a feedback controller which is designed for these two decoupled systems. The effectiveness of the proposed method is confirmed by experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 68–76, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10291
Effective constitutive parameters of a random medium containing small chiral spheres
Authors: Nanbu Yukihisa , Matsuoka Tsuyoshi , Tateiba Mitsuo 
Published: April 2004

AbstractWe have analyzed the effective constitutive parameters for a random medium containing small chiral spheres embedded in an achiral background medium by using our approach. The approach is based on an unconventional multiple scattering method by which wave scattering can be systematically treated in a medium whose dielectric particles are randomly displaced from a uniformly ordered spatial distribution. We have clarified the characteristics of the effective medium parameters by changing the volume fraction and constitutive parameters of chiral spheres. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 11–18, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10294
Three‐dimensional finite element eddy current analysis by using high‐order vector elements
Authors: Hano Mitsuo , Miyamura Takeshi , Hotta Masashi 
Published: April 2004

AbstractSets of high‐order basis functions of a tetrahedral element are systematically constructed and applied to finite element analysis of eddy current problems. A polynomial space is divided into a lot of subspaces assigned on the edges, faces, and a volume of the tetrahedral element. Lagrange‐type vector basis functions of the subspaces are presented. The effect of the high‐order vector elements is investigated by a cubic conductor model located in AC steady‐state magnetic fields. In the calculations using the fundamental and second‐order elements, no convergent value of the eddy current power loss can be obtained in spite of fine meshes because the eddy current shifts to the surface of the conductor. The higher‐order vector elements give the convergent solutions in the coarse meshes. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 60–67, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10306
Performance evaluation of SOFC systems using electrochemical partial oxidation of methane
Authors: Yokoo Masayuki , Take Tetsuo , Ohtsu Satoshi 
Published: April 2004

AbstractWe simulated the performance of systems using a solid oxide fuel cell (SOFC) stack which generates electricity by electrochemical partial oxidation of methane and a conventional steam‐reforming‐type SOFC (SRSOFC) stack. The net thermal efficiency in an atmospheric partial‐oxidation‐type SOFC (POSOFC)‐SRSOFC system was 8% higher than that in an atmospheric SRSOFC system at system outputs of 35 kW or more. The net thermal efficiency of a pressurized POSOFC‐SRSOFC‐gas turbine (GT) system was slightly higher than that of a pressurized SRSOFC‐GT system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 11–19, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10314
Transient current analysis of induction generators for wind power generating system
Authors: Senjyu Tomonobu , Sueyoshi Norihide , Uezato Katsumi , Fujita Hideki 
Published: April 2004

AbstractIn this paper we present a transient current analysis of induction generators used in a wind power system before and after three‐phase fault conditions. First, the basic equations of an induction generator connected to an infinite bus are developed and then transient current analysis formulas are derived for a three‐phase fault before and after fault clearance. We also determine the initial phase angle for the three‐phase fault or the restoration phase angle of the power supply voltages and the time at which the maximum or minimum transient currents flow in the system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 38–45, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10319
Enantiomerically Pure Amines as Substrates for the Ti‐Catalyzed Hydroamination of Alkynes
Authors: Pohlki Frauke , Bytschkov Igor , Siebeneicher Holger , Heutling Andreas , König Wilfried A. , Doye Sven 
Published: April 2004

AbstractFor two representative reactions employing enantiomerically pure (S)‐1‐phenylethylamine and (S)‐1‐cyclohexylethylamine it is shown that Ti‐catalyzed hydroamination reactions of alkynes do not generally take place without partial racemization at the chiral center adjacent to the nitrogen atom. However, identified from a selection of nine Ti catalysts, Cp*2TiMe2 and at least two other catalysts can be used for racemization‐free hydroamination reactions of alkynes. Furthermore, the amount of racemization can be reduced significantly by the addition of pyridine to the reaction mixture. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Amphiphilic Amide Derivatives of D‐Glucaric Acid. Synthesis and Complexing Properties Toward Lanthanide(III) Ions
Authors: Aury Sabrina , Rubini Patrice , Gérardin Christine , Selve Claude 
Published: April 2004

AbstractHydrophobic derivatives of D‐glucaric acid, HOOC−(CHOH)4−CONHR,where R is an alkyl chain having 3, 8, 10, or 12 carbon atoms, have been synthesized from D‐glucaro‐1,4‐lactone and the corresponding amines. The complexing abilities of these compounds toward trivalent lanthanide cations have been studied, using the water‐soluble propyl compound, and compared to that of gulonic acid, which corresponds to the complexing part of these molecules. The formation constants of the complexes have been determined and their structures discussed. The surfactant properties of the C8, C10 and C12 glucaramides and their extracting ability toward LnIII ions have also been evaluated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Enantioselective Synthesis of the Originally Proposed Usneoidone Structure: Evidence for a Structural Revision
Authors: Danet Michèle , Normand‐Bayle Marie , Mahuteau Jacqueline , d'Angelo Jean , Morgant Georges , Desmaële Didier 
Published: April 2004

AbstractThe enantioselective synthesis of the initially proposed structure of usneoidone has been completed according to a convergent strategy in which the key steps were an enantioselective Michael addition involving chiral imines to set up the C12 quaternary center, and the final assembly of the chiral pyran moiety with the aromatic subunit through a cyanohydrin anion alkylation step. The obtained product displays spectroscopic data that significantly differ from the reported values. A putative revised structure in which the pyran ring is opened is proposed for usneoidones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis of Macrocyclic Carbonates with Musk Odor by Ring‐Closing Olefin Metathesis
Authors: Michrowska Anna , Wawrzyniak Piotr , Grela Karol 
Published: April 2004

AbstractThis study shows the efficiency of modern well‐defined ruthenium catalysts for the formation of musk‐odored macrocyclic carbonates with ring sizes between 15−23 atoms. It also reveals that, in these cases, geometric factors are very important and that smaller ring carbonates are difficult to access by ring closing metathesis, even with highly active second‐generation ruthenium catalysts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis and NMR Structural Analysis of 2′‐OMe‐Uridin‐3′‐yl (3′,5′)‐5′‐O‐(N‐Isobutyryl‐2′‐OMe‐Cytidine) Methylthiophosphonates
Authors: Olejniczak Sebastian , Potrzebowski Marek J. , Wozniak Lucyna A. 
Published: April 2004

AbstractDetailed analysis of the molecular structures of both the Fast‐eluted and the Slow‐eluted (the notation Slow and Fast corresponds to the relative mobility properties of compounds in silica gel column chromatography under normal phase conditions, see Exp. Sect. for details) diastereomers of 5′‐OH‐2′‐OMe‐uridin‐3′‐yl (3′,5′)‐5′‐O‐(N‐isobutyryl‐2′‐OMe‐cytidine) methylthiophosphonate (1) was performed with the aid of 1H, 13C, 1D and 2D homo‐ and heteronuclear PFG (Pulse Field Gradient) NMR studies. The absolute configurations [(RP) and (SP)] of the diastereomers of 1 were unambiguously assigned by 1H ROESY experiments. The pseudorotation parameters of the ribose ring were calculated with the aid of the PSEUDOROT program, and compared with data obtained from X‐ray structure analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis of 2,4‐Furanophanes by Palladium‐Catalyzed Macrocyclization Reactions of 1,n‐Diallenyl Diketones
Authors: Hashmi A. Stephen K. , Schwarz Lothar , Bolte Michael 
Published: April 2004

AbstractThe 1,n‐diallenyl diketones 8a−j were prepared and subjected to reactions with the [PdCl2(MeCN)2] catalyst. Upon decreasing the length of the bridge between the allenyl ketone units, first we obtained the (E) isomer 10 as the macrocyclic product and then the (Z) isomer 11 accompanied by the exocyclic double bond isomer 12. In all cases, the open‐chained 1,n‐difuryl alkanes were isolated as side‐products. The analogous preparation and conversion of the diallenyl diketones 19 and 24, which have even longer bridges and ether‐functionalities, delivered the 20‐ to 52‐membered macrocycles 21a, 21b, 26a, and 26b with only the expected (E) configuration of the double bond. The ring closure of a furan derivative, having vinyl groups in its substituents at the 2‐ and 4‐positions, to a related product by Ru‐catalyzed olefin metathesis delivered yields similar to the Pd‐catalyzed macrocyclization, but provided a mixture of both double bond isomers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Design of Strong, Neutral Organic Superacids: DFT‐B3LYP Calculations on Some Isobenzofulvene Derivatives
Authors: Maksić Zvonimir B. , Vianello Robert 
Published: April 2004

AbstractIsobenzofulvenes heavily substituted by cyano groups provide very good candidates for neutral organic superacids of unprecedented strength. The latter can be additionally enhanced by the anionic corona effect realized by interaction between the propyl−BX2 chain, where X = F, Cl and Br, and the O− atom in the corresponding conjugate bases. The main reason for the highly pronounced acidity is found, however, in the aromatization of the isobenzofulvene moiety upon deprotonation, which, in turn, is assisted by the electron‐withdrawing CN groups. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Desymmetrization of Prochiral Phosphanes Using Derivatives of (−)‐Cytisine
Authors: Johansson Magnus J. , Schwartz Lennart O. , Amedjkouh Mohamed , Kann Nina C. 
Published: April 2004

AbstractHistorically, (−)‐sparteine·sec‐BuLi has been used to desymmetrize prochiral phosphanes. In this report, derivatives of an alkaloid extracted from the seeds of Laburnum anagyroides have been utilized to mimic (+)‐sparteine, which is not readily available. In several cases, the enantioselectivities achieved with the (+)‐sparteine surrogates outperformed (−)‐sparteine itself in the deprotonation of alkyl‐substituted (as well as aryl‐substituted) prochiral phosphane derivatives. In addition, use of these surrogates allows a new methodology for a chiral switch in phosphorus chemistry. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)