bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Fragmentations and the “Feeling of Goal” in Computer‐Assisted Synthesis.
Authors: LUSHNIKOV D. E. , ZEFIROV N. S. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Stereocontrolled Synthesis of 2,6‐Dideoxy Sugars and Its Application to Synthesis of Natural Products
Authors: TOSHIMA K. , TATSUTA K. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solution Chemistry of Arsenic Selenides: Synthesis, Spectroscopy and the X‐Ray Structures of (PPh4)2(AsnSe6), n = 2, 4.
Authors: ANSARI M. A. , IBERS J. A. , O'NEAL S. C. , PENNINGTON W. T. , KOLIS J. W. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Multipoint Control by Diastereo‐Differentiative Assembly of Three Components with Palladium Catalyst.
Authors: TORII S. , OKUMOTO H. , OZAKI H. , NAKAYASU S. , TADOKORO T. , KOTANI T. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of N‐Ethoxycarbonylmethyl Geissman‐Waiss Lactone: Unusual Epimerization of α,β‐Unsaturated γ‐Lactone.
Authors: TANAKA M. , MURAKAMI T. , SUEMUNE H. , SAKAI K. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 1,2,3‐Triazabutadienes. Part 22. Photochemistry of 1‐(Carbmethoxyaryl)‐ and 1‐(Carboxyaryl)‐3‐(3‐alkylbenzthiazolin‐2‐ylidene)‐triazenes as Potential CEL‐Dyes.
Authors: FANGHAENEL E. , BAUROTH J. U. , HENTSCHEL H. , GUSSMANN F. , ALZYADI H. , ORTMANN W. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Study of the Diazoimine/Triazole Equilibria for Substituted Thiazoles and Thiadiazoles.
Authors: L'ABBE G. , LUYTEN I. , TOPPET S. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Structural and Conformational Study of Some Amides Derived from 3,7‐Dimethyl‐9‐amino‐3,7‐diazabicyclo(3.3.1)nonane‐9‐carboxamide.
Authors: FERNANDEZ M. J. , TOLEDANO M. S. , GALVEZ E. , MATESANZ E. , MARTINEZ‐RIPOLL M. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: New Developments in the Synthesis and SAR of Several Series of 2‐ Aminothiazolyl Cephalosporins
Authors: DUERCKHEIMER W. , FISCHER G. , LATTRELL R. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Enantioselective Enzymic Synthesis of Prostaglandin Synthons in Multiphase Reaction Media.
Authors: SCHAPOEHLER S. , SCHEPER T. , SCHUEGERL K. , BARENSCHEE E. R. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Use of Organometallic Chemistry for Hydrotreatment Catalyst Development
Authors: HIRSCHON A. S. , WILSON R. B. JUN. 
Published: July 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Responses of radio interference measuring apparatus employing an envelope quasi‐peak detector
Authors: Sugiura Akira , Oguchi Tetsuo , Nagatomo Hirojiro 
Published: July 2007

AbstractIn conventional radio interference measuring apparatus, the direct‐QP detection method is used. In this method, intermediate frequency output is added directly to a quasi‐peak detector to obtain an output corresponding to the quasi‐peak level of the interference. However, a new type of QP detection method has recently been used in the radio interference measuring apparatus as demonstrated in the spectrum analyzer with the quasi‐peak detection capability. In this method, the intermediate frequency output is first added to an envelope detector and then to quasi‐peak detector. But it is not yet known if this measuring apparatus with its combination of detector, the envelope‐QP detector, satisfies all standards, including present CISPR specifications. The latter is determined based on the response characteristics of the direct‐QP detector system. In this paper, theoretical computer comparison has been made between the direct‐QP detector system and the envelope‐QP detector system to study responses to Gaussian noise and the repeated pulse input. It is found that the measuring apparatus with an envelope QP detector does not easily satisfy the present CISPR specifications. To improve the response characteristics of this new apparatus having the envelope‐QP detector, guidelines, have been indicated for the bandwidth and the charge and discharge time constants.
Broadband circularly polarized microstrip array antenna with coplanar feed
Authors: Hori Toshikazu , Nakajima Nobuo 
Published: July 2007

AbstractBand broadening and optimization of a microstrip array antenna are investigated and a design method is presented for an S‐band satellite marine communication antenna. Validity of this design is confirmed by experiment. Bandwidth as large as 13% is achieved with a parasitic element in which the VSWR remains less than 1.5. The coplanar arrangement, in which the radiator and feed circuit are in the same plane, permits simple, low‐less structure. Based on these investigations a microstrip array antenna is fabricated for S‐band satellite marine communications which has a relative bandwidth greater than 8.5%, gain greater than 18.8 dBi, efficiency above 62%, sidelobe level below ‐22 dB and VSWR less than 1.5.
Radar reflector with bidirectional communication capability
Authors: Hasebe Nozomu , Sugiyama Hiroshi , Kuramoto Akio , Onoe Morio 
Published: July 2007

AbstractA radar reflector with bidirectional communication capability is presented. The reflector consists of a Luneberg lens and a reflecting plate combining a microstrip antenna and a switching circuit, which is placed at the focus of the lens. The reflector is capable of transmitting information from a reflector site as well as receiving signals from a radar station. Characteristics of the reflector are analyzed by the moment method using a wire‐grid model. The results are confirmed by experimental measurements. An experimental model of the reflector yields an antenna gain of 26.5 dB and a modulation ratio of reflectivity of 13 dB. A passive telemetry system covering a wide area can be built with a radar station and a group of these reflectors. Alternatively, a Luneberg lens having many reflecting plates can respond to plural radar stations simultaneously and independently.
Impulse train equivalent excitation signals for high‐quality speech synthesis
Authors: Imai Satoshi , Furuichi Chieko 
Published: July 2007

AbstractIn the speech synthesis using filters, other than the impulse train, some special pulse trains such as an excitation signal are used, especially the pulse train by Barker sequence and the pulse train obtained by averaging in time the energy of the signal. However, they do not produce a high‐quality synthesized speech. By contrast, the possibility exists that a high‐quality speech synthesis can be achieved by utilizing the residual speech as the excitation signal. In this case, a certain data compression must be applied to the residual signal. Several useful methods are known for coding the residual speech, such as base‐band signal coding and multipulse coding. For efficient speech data compression or realization of high‐quality speech synthesis by a rule‐based speech synthesis, the lack of rules or formulation for the excitation source is a serious problem. To realize a high‐quality speech synthesis by a rule‐based excitation, a high‐quality impulse train equivalent excitation signal is needed to replace the usual impulse train. From such a viewpoint, this paper first performed the very‐short‐term analysis of the residual speech, confirming that the spectral envelope of the voiced sound interval varies with time in quite a characteristic way. A method of generating the impulse train equivalent signal (FTSITES) with the spectral envelope and fine‐time structure is proposed according to the result of analysis. It is shown that a high‐quality speech synthesis is achieved by utilizing FTSITES as the excitation signal.
Examples of single‐error‐correcting perfect BCD‐AN codes
Authors: Goto Munehiro 
Published: July 2007

AbstractPerfect AN codes are those with the least redundancy under constant code length and error correcting capability. The existence of perfect codes has been studied for generalized r‐ary represented AN codes and symmetric multivalue represented AN codes to apply them to multivalued arithmetic circuits. In this paper we define single‐error‐correcting perfect BCN (Binary Coded Decimal)‐AN codes and obtain the conditions under which the perfect BCN‐AN codes exist. These conditions do not depend on the weight sequence itself used in BDC representation of code words, but on the class to which the weight sequence belongs. By using these conditions we prove that for some classes of the BCD representation including (8421) representation there exists no perfect BCD‐AN code. For some of the remaining classes we obtain examples of generators of perfect BCD‐AN codes through exhaustive computation.
Crosstalk noise analysis of wiring on the printed circuit board
Authors: Schibuya Noboru , Ito Kenichi , Homma Tsuyoshi , Takagi Haruo , Kumamoto Kayoko 
Published: July 2007

AbstractRecently, progress in the high‐density wiring technique on a printed circuit board (PCB) has been remarkable. Thus the problem of malfunctions due to crosstalk noise occurring on the signal line must be addressed. The authors have been developing the noise estimation system for PCB named NESSY and a program to calculate the capacitance of multiconductor system (CALCAP). In NESSY, the wiring pattern is divided into small segments, which comprise the equivalent element circuit. The partial capacitance of the printed pattern is calculated by solving the integral equation and using the image method in CALCAP. The crosstalk analysis of equivalent circuit was made by the circuit simulation program.Among the results of this analysis, crosstalk noise using the partial element equivalent circuit (PEEC) agrees quite well with the measurement. The crosstalk noise should be anticipated by the close coupling theory in the case of frequently used wiring (both the width of signal line and line spacing are less than 1 mm). The crosstalk noise voltage was relatively large in the case of impedance mismatching. The far end crosstalk noise, previously neglected in most cases, becomes especially large.
Scattering of hermite‐gaussian beam waves by two parallel conducting cylinders
Authors: Kojim Toshitaka , Ieguchi Masafumi , Ishikura Akihiko , Moriyuki Toshihiro 
Published: July 2007

AbstractScattering of Hermite‐Gaussian beams by two‐parallel conducting cylinders is considered in this paper. Hermite‐Gaussian beams of arbitrary order incident on the cylinders, are expanded in a Fourier‐series with respect to each cylindrical coordinate system, and multiply scattered fields by both cylinders are derived rigorously. Since the analysis for the fundamental beam incidence already has been done, this paper carries out the theoretical analysis for the first‐ or second‐order beam incidence. Several numerical examples of the far‐zone scattering pattern and the equi‐amplitude and phase distribution of the near field are shown. When the configuration of the twocylinder scattering system is symmetric with respect to the beam axis of the first‐order beam, the scattering pattern becomes symmetric with respect to the beam axis and deep dips are produced in the directions of forward and backward scattering. Moreover, it is shown that both deep dips and the symmetry of the scattering pattern disappear even if an imperceptible asymmetry of the configuration of the scattering system occurs. The distribution of the equi‐phase planes near the cylinders, which have not yet appeared in problems of this kind, is depicted and the interference of the multiply scattered fields and the incident beam is illustrated.
Discrete cosine transform coding with gain/shape vector quantizers for picture signals
Authors: Saito Takahiro , Takeo Hideya , Aizawa Kiyoharu , Harashima Hiroshi , Miyakawas Hiroshi 
Published: July 2007

AbstractA gain/shape vector quantizer for orthogonal transform domain has been designed based on a previous paper [11] on a gain/shape vector quantizer for a spherically symmetric random source. Such a design method is used in the design of a discrete cosine transform encoder with gain/shape vector quantizer. This encoder is similar to that described in [7] except in the following: (i) it has a gain/shape codebook; and (ii) its normalized coefficients of discrete cosine transform are modeled as having spherically symmetric distribution. The S/N rendition of this encoder is 1.0 – 2.5 dB better than that of the DCT coding scheme with Max‐type scalar quantizer at the same bit rate. Furthermore, in spite of its similarity to the conventinoal discrete cosine transform coding scheme with vector quantizer [7], the encoder introduced in this paper delivers higher S/N using the same number of multiplications for the quantization of normalized coefficients, and/or the same amount of memory for the codebook.
Reflection of surface acoustic waves from gratings on the surface of piezoelectric substrates
Authors: Suzuki Yuji , Shimizu Hiroshi 
Published: July 2007

AbstractTo apply grating reflectors to surface acoustic wave resonators, it is necessary to have knowledge about the reflection characteristics as a function of the grating parameters. This paper discusses the reflection of the surface acoustic wave by the grating composed of periodic metal‐strips on a piezoelectric substrate. The surface wave incident upon the grating is reflected by electrical and mechanical surface perturbations due to the strips. The reflection characteristics are analyzed by the perturbation theory and the coupled mode theory, considering the two perturbations. By numerical calculation, it is shown that the manner of superposition of the two perturbations depends on the material of the substrate, the cut‐angle and the strip material. For LiNbO3, LiTaO3and quartz substrates, the calculated value is compared with the experimental values reported elsewhere indicating good agreement.
Optical switching networks using tree‐structured waveguide optical switches
Authors: Habara Keishi , Kikuchi Katsuaki 
Published: July 2007

AbstractTo make a large‐sized optical matrix is an important subject in realizing optical switching systems. Although optical matrices using waveguide optical switches have potential from the viewpoint of high speed and circuit integration, they are limited in the number of input/output terminals (up to between 4 and 8) due to the insertion loss and multiple crosstalk noise. To reduce these disadvantages, this paper offers optical switching networks using tree‐structuredNx 1 waveguide switches as fundamental elements. Approximated equations for the insertion loss and the multiple crosstalk are given and it is shown that those in the proposed networks are approximately proportional to the number of stages in the tree structure. A 4 × 4 optical highway switch using Ti:LiNbO3tree‐structured directional couplers was tested to confirm its switching capability. The experimental results obtained have a good agreement with the equations of the insertion loss and the multiple crosstalk characteristic. By using these equations, the size of the realizable switching system was estimated; a highway switch having 32 to 64 terminals is found to be possible with the present technology.
A simple multiplexing method for pulsed analog signal and digital signal in optical communications
Authors: Kusakabe Hiroyuki , Nakagawa Masao 
Published: July 2007

AbstractThere is a need for simultaneous optical transmission of two distinct signals, broadband analog video signal, and digitalized PCM voice signal or digital data signal, such as in TV transmission. Conventional multiplexing methods such as FDM, TDM, and WDM, can be applied, but some problems remain to be solved. This paper proposes a simple multiplexing method for a pulsed analog signal and digital signal, which are multiplexed in different directions, time and amplitude. Digital signals can be multiplexed easily without affecting pulsed analog signals, and, moreover, the two signals can easily be separated at the receiver without a special separating circuit. The proposed method is analyzed both by theory and simulation, and it is shown that with very slight deterioration of the analog signal, the mulitplex transmission of digital signals with good quality can be obtained.
Design of offset dual reflector type multibeam antenna composed of parabolic reflector and shaped subreflector
Authors: Makino Shigeru , Katagi Takashi , Kobayashi Yuji 
Published: July 2007

AbstractA method for correcting the subreflector surface is presented for the offset dual reflector multibeam antenna consisting of a parabolic main reflector. It is intended that the characteristics with a deflected beam are improved without degrading those with a nondeflected beam. It is seen that the portion used in the subreflector depends on the deflection direction so that only the peripheral region of the subreflector is corrected. In the present design method, the location of the primary radiator and the amount of shaping of the subreflector are determined by an asymptotic method in such a way that the aberration at the antenna aperture corresponding to the directions of the desired multibeam is minimized. The first‐order aberration is corrected by modifying the location of the primary radiator and the remaining aberration by shaping the surface of the subreflector. The present design method has been applied to an offset Gregorian antenna with a two‐dimensional beam deflection, and its effectiveness is confirmed.
Adaptive discrete cosine transform coding with gain/shape vector quantizers for picture signals
Authors: Saito Takahiro , Takeo Hideya , Aizawa Kiyoharu , Harashima Hiroshi 
Published: July 2007

AbstractThe authors have previously proposed a quantization scheme in which the ac discrete cosine transform coefficients after normalization are quantized by the gain/shape vector quantizer (called DCT‐G/SVQ). It is shown from the relation between the quantization complexity and the S/N ratio that DCT‐G/SVQ exhibits a better performance than the discrete cosine transform coding with vector quantization (called DCT‐VQ) discussed in the literature [6]. This paper proposes the adaptive DCT‐G/SVQ, in which the adaptive control is introduced for the coding parameters of DCT‐G/SVQ. Two methods of adaptive control are considered–the modeselection and the recursive adaptation. The adaptive DCT‐G/SVQ has a better performance than the traditional adaptive discrete cosine transform coding using the scalar quantizer. In other words, the S/N ratio is improved by 1.0 to 1.5 dB in the mode‐selection adaptive control coding at the same coding rate. The S/N ratio in the recursive adaptive control coding is improved by 0.5 to 1.0 dB. The adaptive DCT‐G/SVQ based on the mode‐selection control exhibits nearly the same coding performance as the adaptive DCT‐VQ of [9] with the same adaptive control scheme, but is superior since it requires less complexity in quantization.
Scanning characteristics of spherical dome antenna composed of arcing dipole array antennas including the effects of mutual coupling between elements
Authors: Maeda Tadahiko , Sawaya Kunio , Adachi Saburo , Mushiake Yasuto 
Published: July 2007

AbstractFor a beam scanning at high speed over a wide angle, a dome antenna has been proposed. Past research on the dome antenna treated the dome parts as an ideal lens. However, the concrete arrangement of antenna elements outside and inside the dome and their mutual coupling have not been considered. Based on our past work on the electromagnetic field inside a concave spherical surface, this paper describes the results of analysis performed on the most fundamental dome antenna composed of arcing array antennas. For the array elements we considered dipole antennas. We obtained the radiation characteristics considering the mutual coupling among the elements of the radiators on the convex surface, the elements of the collector on the concave surface, and the coupling between the elements of the collector and the elements of the primary radiator. We determined the excitation currents in the elements of the primary radiator so that the currents in the elements of the radiator become co‐phase and uniform amplitude along the direction of the main beam. We obtained the radiation characteristics, and confirmed that over the range from 0 to 110°, beam scanning at almost a constant gain was possible. Next, we suppressed the levels of the sidelobes. We showed that up to a maximum of 18 dB, we suppressed the levels of the sidelobes compared to the co‐phase excitation. Finally, we discussed the influence of the mutual coupling between the elements of the radiator and the elements of the collector on the directivity.