bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detail study of the Raman‐active modes in carbon nanotubes
Authors: Mohr M. , Machón M. , Thomsen C. , Milošević I. , Damnjanović M. 
Published: September 2007

AbstractThe Raman‐active A1‐modes in carbon nanotubes are often used for characterizing nanotube samples. The fully‐symmetric radial‐breathing mode and the high‐energy mode (HEM) have small non‐radial and non‐tangential components, respectively. Neglecting these components results in errors for phonon frequency and electron–phonon coupling calculations. We present a model to estimate these non‐radial components. For the HEM we find an anharmonicity that stems from the three‐fold coordination of the C atoms. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling suspended carbon nanotube resonators
Authors: Poot M. , Witkamp B. , Otte M. A. , van der Zant H. S. J. 
Published: September 2007

AbstractWe study the bending mode vibration in suspended carbon nanotubes. Based on the theory of continuum mechanics, we have developed a model for flexural oscillations of suspended nanotubes. A detailed analysis of the electrostatic force, the scaling behavior of the model and the gate tuning is given. The model is used to fit experimental data and to reconstruct the gate dependence of the tension and strain in the nanotube. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of fullerene dimers with controllable length
Authors: Porfyrakis Kyriakos , Sambrook Mark R. , Hingston Timothy J. , Zhang Jinying , Ardavan Arzhang , Briggs G. Andrew D. 
Published: September 2007

AbstractFullerenes have attracted interest as materials for next‐generation electronic devices. Considerable effort has been focused on the chemical functionalization of fullerenes. Fullerene dimers possess interesting photophysical effects. Herein we present an overview of our efforts on the synthesis and characterization of different types of fullerene dimers such as directly bonded dimers, a short chain C60 dimer and other dimers with bridge molecules of varying length. By choosing the bridge‐molecule one can control the interfullerene spacing and thus tune the electronic interaction between the fullerenes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Catalyst size dependencies for carbon nanotube synthesis
Authors: Rümmeli M. H. , Kramberger C. , Schäffel F. , Borowiak‐Palen E. , Gemming T. , Rellinghaus B. , Jost O. , Löffler M. , Ayala P. , Pichler T. , Kalenczuk R. J. 
Published: September 2007

AbstractWe have systematically explored the synthesis parameters in laser evaporation and CVD for the synthesis of carbon nanotubes. Our findings point to a dependence of the resultant tubes on the volume to surface area ratio of the catalyst particle. The data furthers our understanding on the nucleation of carbon nanotubes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Raman imaging for processing and process monitoring for nanotube devices
Authors: Stampfer C. , Bürli A. , Jungen A. , Hierold C. 
Published: September 2007

AbstractWe present a process flow for single‐walled carbon nanotube electronic and electromechanical device fabrication, where the technique of Raman imaging has been used (i) for the fabrication process monitoring itself and (ii) to consequently observe modifications of the integrated nanotubes during processing. First, extended Raman images (i.e. maps) have been used to locate nanotubes relative to reference alignment markers enabling to distinguish semiconducting from metallic carbon nanotubes before electrically contacting them. Second, we used Raman imaging to monitor individual process steps. We show that the radial breathing mode (RBM) signal is very sensitive to standard processes used to contact individual nanotubes. Moreover, we conclude that HF etching for releasing nanotubes leads to a significant increase of the defect‐induced D line. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Infrared spectroscopy on the rotor–stator compounds C60–C8H8 and C70–C8H8 under pressure
Authors: Thirunavukkuarasu K. , Kuntscher C. A. , Bényei Gy. , Jalsovszky I. , Klupp G. , Kamarás K. , Kováts É. , Pekker S. 
Published: September 2007

AbstractPressure‐dependent infrared transmittance measurements on C60–C8H8 and C70–C8H8 were performed at room temperature for pressures up to 10 GPa. The pressure dependence of the vibrational modes suggest the occurrence of orientational ordering transitions induced at 0.5 GPa and 0.8 GPa in C60–C8H8 and C70–C8H8, respectively. In addition, a second anomaly was observed at around 1.3 GPa for C60–C8H8, which could be attributed to the transition to a second, orientationally ordered phase. According to the infrared response, the cubane molecules in C70–C8H8 are more sensitive to the application of pressure compared to C60–C8H8, suggesting larger intermolecular interactions in C70–C8H8. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tube encapsulation effects in various carbon nanotube systems
Authors: Christofilos D. , Arvanitidis J. , Efthimiopoulos E. , Zhao X. , Ando Y. , Takenobu T. , Iwasa Y. , Kataura H. , Ves S. , Kourouklis G. A. 
Published: September 2007

AbstractIn this work, we compare the pressure response of single‐ (SWCNTs), double‐ (DWCNTs) and multi‐wall carbon nanotubes (MWCNTs), as reflected in the normalized pressure derivatives (Γ ‐parameters) of their radial breathing modes (RBMs), probed by Raman spectroscopy. The qualitative characteristics of the experimentally obtained Γ values are well reproduced by a simple anharmonic model. In a nanotube system, the diameters and the number of the constituent coaxial tubes as well as their mutual interaction – strongly depending on their spacing – define its pressure response. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic transport in ambipolar silicon nanowires
Authors: Colli A. , Pisana S. , Fasoli A. , Robertson J. , Ferrari A. C. 
Published: September 2007

AbstractWe investigate and compare the electronic transport in ambipolar SiNWs as a function of the metal choosen for contact deposition. The wires are grown by Au‐catalyzed vapour‐transport and exhibit crystalline cores about 15–20 nm in thickness. The suitability of Ti and Ni contacts on SiNWs is evaluated in terms of contact resistance and band‐alignment. The beneficial effect of a rapid‐thermal‐annealing at mild temperatures (400 °C) is also investigated. We observe that annealed Ni contacts yield the lowest device resistance and highest ON/OFF ratio. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sonication of porphyrin–nanotube composites: a cautionary tale
Authors: Ní Mhuircheartaigh E. M. , Blau W. J. , Prato M. , Giordani S. 
Published: September 2007

AbstractWe report the spectroscopic changes of tetraphenylporphyrin carbon nanotube composites in a variety of chlorinated solvents such as chloroform, dichloroethane and dichlorobenzene as a result of sonication. Detailed data analysis suggests that protonation of the porphyrin core nitrogen atoms occurs as a result of sonodegradation of the solvent molecules. Extreme care must be taken when working with carbon nanotube composite solutions in chlorinated solvents, as sonication is always employed to disperse the nanotubes. This finding is of enormous relevance to the materials chemistry community since these solvents are widely used in preparation of carbon nanotube composite solutions. When working with molecules that are capable of acting as a base some amount of protonation is inevitable and this may dramatically change the physicochemical properties of the composite materials. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Standing‐wave observations in single‐wall carbon nanotube quantum dots and Y‐junction rings
Authors: Grimm Daniel , Latgé Andrea , Venezuela Pedro 
Published: September 2007

AbstractStanding electronic wave formation inside single walled carbon nanotube Y‐junction rings and quantum dots with a quantum‐dot‐like quadratic dispersion is reported. Remarkably, the detailed structural defect configurations play only a minor role and the standing wave oscillation dispersions are mainly triggered by the electronic properties of the pristine constituent tubes. This raises the possibility of using both structures as nanoscale tuneable electronic switching devices. Near the Fermi level, quantum dots show smooth dispersing oscillations reminiscent of the finite pristine tube eigenvalues. However, localized density of states peaks are found in YJRs, which are identified as interference effects of the double‐slit interferometer. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of 1‐D nanoSiC‐derived nanoporous carbon
Authors: Huczko A. , Osica M. , Bystrzejewski M. , Lange H. , Cudziło S. , Leis J. , Arulepp M. 
Published: September 2007

AbstractThe basic interest of this study was to see whether and how the sorption and electrical double layer (EDL) properties of porous whiskers‐like carbide‐derived carbon (CDC) from SiC nanofibres differ from the commercial SiC‐derived carbon. SiC nanofibres were obtained via combustion synthesis route from CaSi2/PTFE mixture. Resulting carbon material was analysed by powder XRD and low‐temperature nitrogen sorption methods. EDL characteristics were evaluated and compared with CDC obtained from α‐SiC and β‐SiC powders. The cyclic voltammograms and the electrochemical impedance spectroscopy show that the electrical double layer performance of SiC nanofibres‐derived amorphous carbon is better than most of the common pyrolytically made carbons. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Catalytic chemical vapour deposition growth of single wall carbon nanotube films on different substrates for transparent electronic devices
Authors: Ansaldo A. , Skakalova V. , Di Zitti E. , Ricci D. , Roth S. 
Published: September 2007

AbstractIn this work we present our results concerning the growth of transparent carbon nanotube networks. The networks have been successfully grown on both oxidized silicon and quartz‐glass substrates. Conductive and optical properties of these transparent films are discussed and compared to those obtained with other approaches. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vector quantization of mel‐cepstral coefficients using distortion measure for spectral analysis
Authors: Takahashi Toru , Tokuda Keiichi , Kobayashi Takao , Kitamura Tadashi 
Published: September 2007

AbstractThis paper proposes a method for vector quantization of mel‐cepstral coefficients based on a measure for spectral analysis. It is a method in which the match between the input signal within the frame and the mel‐cepstral coefficients stored in the codebook is evaluated by using a statistical measure for spectral analysis, and the quantized mel‐cepstral coefficients are derived. The codebook training algorithm for the proposed method is also presented. The proposed method is further applied to multistage vector quantization. It is shown by an experiment using a speech database that the proposed method with a codebook size of 9 bits can achieve the same quantization distortion as the conventional 12‐bit method (vector quantization based on Euclidean distance between mel‐cepstral coefficients). © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(13): 104–114, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10432
Simultaneous optimization of class configuration and feature space for object recognition
Authors: Shimano Mihoko , Nagao Kenji 
Published: September 2007

AbstractA new algorithm for object classification based on an extension of Fisher's discriminant analysis is presented. Object recognition algorithms using the standard Fisher's algorithm, such as the Fisherface, train the classifier using sample‐class pairs, where, for the classes, object categories determined in the application systems are used directly. In contrast, the new algorithm automatically produces subclasses, within each predetermined category, that are actually used for classification, via unsupervised learning. In order to perform this, we combine Fisher's discriminant analysis with the Akaike Information Criterion, optimizing the class configuration, that is, sample‐subclass correspondences, and the feature extraction function simultaneously, thereby improving the potential of class separability. By applying this new method to face recognition, we show how it outperforms the traditional Fisher‐based method. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(13): 72–81, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20378
Visual kansei modeling based on focal area analysis and hierarchical classification
Authors: Tada Masahiro , Kato Toshikazu 
Published: September 2007

AbstractThis paper discusses a modeling technique for visual kansei (visual impression), which differs depending on the individual user. The visual impression is considered at two levels, the impression at the physiological level, which does not differ much between individuals, and the impression at the psychological level, which differs according to the individual's knowledge and experience. The modeling technique for the impression at the physiological level is considered as follows. The image feature parameters simulating the feature extraction mechanism of the visual perception process are defined and are extracted from the image. A hierarchical classification of the database simulating the human intuitive image classification process, image structure estimation using MDL, and discrimination analysis are combined to produce a modeling technique for the impression at the psychological level. After combining the modeling techniques at the physiological and psychological levels, the method is applied to a similar image retrieval system. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(13): 58–71, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20400
Mechanism of regulating execution performance for process group byexecutionresource ontenderoperating system
Authors: Tabata Toshihiro , Nomura Yoshinari , Taniguchi Hideo 
Published: September 2007

AbstractWith increases in the performance of computers, it has become possible to provide a large number of services on a single computer. However, since the required execution performance can vary from service to service, it is necessary to guarantee execution performance for each service individually. In addition, it is common for a single service to be composed of multiple processes. Consequently, the ability to regulate execution performance for units consisting of multiple processes is desirable. Therefore, in this paper we propose a mechanism for regulating the execution performance of process groups usingexecutionresources that encapsulate the assignable processor units designed for the Tender operating system. Specifically,executionsare managed in a tree‐structure and we then regulate execution performance by associating processes with these executions. In addition, we show via an implementation and evaluations that the proposed method is able to regulate the execution performance of process groups well and present an evaluation that makes use of a Web server. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(14): 63–78, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20403
A 3D log‐polar transform for pattern recognition
Authors: Nakata Takayuki , Bao Yue , Fujiwara Naofumi 
Published: September 2007

AbstractThe log‐polar transformation is a model of the foveal sensor, which is often seen in the visual apparatus of living organisms. The log‐polar transformation is widely known in the field of image recognition, and has often been used for facial image recognition. However, this detection method is limited to 2D environments, since it is invariant only to scaling and rotation. This paper proposes a new log‐polar transformation which also detects affine transformation parameters. The proposed method can detect the posture of a 2D image in a 3D environment, as well as scaling and rotation in a 2D environment. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(13): 49–57, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20564
A superstabilizing spanning tree protocol for a link failure
Authors: Katayama Yoshiaki , Hasegawa Toshiyuki , Takahashi Naohisa 
Published: September 2007

AbstractA self‐stabilizing protocol is a distributed protocol that can eventually solve the problem (reach a legitimate configuration) even when started from an arbitrary initial (global) configuration. These protocols do not make any assumptions about the initial state, and so can tolerate any transient failures that may occur during the execution of the protocol. Superstabilizing protocols offer an even higher degree of fault tolerance over the superior fault tolerance of self‐stabilizing protocols. A superstabilizing protocol is a self‐stabilizing protocol that has a “passage predicate” that is guaranteed to be satisfied by all of the network configurations that appear during the execution of the protocol from when a failure occurs in a legitimate configuration until restabilization. This paper proposes a superstabilizing protocol for constructing a spanning tree that is tolerant of any single arbitrary link failure. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(14): 41–51, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20656
Robust depth map acquisition against depth edges with silhouette consistency
Authors: Iiyama Masaaki , Kakusho Koh , Minoh Michihiko 
Published: September 2007

AbstractThe authors propose a method to measure the smooth curved surface of an object and the depressed surface of an object which cannot be measured using the visual hull method by using a needle diagram obtained via photometric stereo. Errors occur in the distance map as a result of depth edges when recovering a distance map using a needle diagram. In order to reduce these errors, the silhouettes from other directions are used. The distance map restored without taking into consideration the depth edges often lacks consistency with the silhouettes obtained from other directions. The authors take advantage of this feature, define the energy representing the consistency between the distance map and the silhouette as well as the consistency between the distance map and the needle diagram, and then reduce the errors in the distance map by obtaining a distance map which minimizes this energy. Through experiments using the proposed method on simulation data and a real object, the authors evaluate the effectiveness of the proposed method. © 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(14): 29–40, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20763
Practical calculation of the torsional stiffness radius of multistorey tall buildings
Authors: Makarios T. 
Published: September 2007

AbstractThe present paper refers to the definition of the torsional stiffness radii of multistorey tall buildings using both the continuous and the discrete model of the structure. The magnitude of the torsional stiffness radius of a building is the most important structural characteristic in order to explain the torsional behaviour of a building during an earthquake as it directly affects the building's torsional flexibility. The importance of the torsional flexibility of buildings is recognized by contemporary Seismic Codes that propose a grid of torsional provisions in order to avoid soft‐storey operation due to floor torsional vibrations around a vertical axis. However, contrary to single‐storey buildings, the torsional stiffness radius of multistorey buildings is not defined directly because both the translational and torsional stiffness of these buildings are expressed in matrix form. In the present paper, this weakness has been overcome using the continuous model of the structure, from which the torsional stiffness radius of a general monosymmetric multistorey tall system arises via a closed mathematical equation. The discrete model of the structure has numerically verified this closed mathematical equation. Copyright © 2007 John Wiley & Sons, Ltd.
A simple method for the deflection analysis of tall wall‐frame building structures under horizontal load
Authors: Zalka K. A. 
Published: September 2007

AbstractNew closed‐form formulae are developed for the static deflection of symmetric multi‐storey buildings braced by moment‐resisting (and/or braced) frames, (coupled) shear walls and cores. The behaviour is characterized by shear, local bending and global bending, and corresponding stiffnesses. The analysis is based on that of a single moment‐resisting framework. A closed‐form solution is presented for the lateral deflection. The procedure is then extended to a system of frameworks, (coupled) shear walls and cores by creating an equivalent column which represents the whole structure. Another closed‐form solution is presented, this time for the deflection of the whole building. The deflection is defined by three distinctive parts: the bending deflection of the building, the shear part of the deflection and interaction between the bending and shear modes. It is shown that the interaction between the bending and shear modes is always beneficial as it reduces the deflection of the structure. According to a comprehensive accuracy analysis of 270 multi‐storey building structures with both reinforced concrete and steel bracing units and covering wide ranges of stiffness, the proposed closed‐form solution for the top deflection is simple and reliable: the average error of the formula was 4%. A worked example demonstrates the ease of use of the method. Copyright © 2007 John Wiley & Sons, Ltd.
Characterization of essential and toxic elements in cephalopod tissues by EDXRF and AAS
Authors: Manso M. , Carvalho M. L. , Nunes M. L. 
Published: September 2007

AbstractConcentrations of K, Ca, Cr, Fe, Ni, Cu, Zn, Se, Rb, Sr, Cd, Hg and Pb were measured in the muscle, digestive glands and gonads of Octopus vulgaris, Lolligo vulgaris and Sepia officinalis captured in the west and south coast of Portugal. Essential elements (K, Ca, Fe, Cu, Zn, Se, Rb and Sr) were obtained by energy dispersive x‐ray fluorescence spectrometry, while toxic elements (Cr, Ni, Cd, Hg and Pb) were obtained by atomic absorption spectrometry. The latter technique was used owing to its higher sensitivity, since these elements were not detected by the first technique. The tissues of the three species present a similar pattern for essential elements. Potassium and Ca are present at the highest concentration in all the studied samples. The highest levels for toxic elements were found in the digestive glands, exceeding the maximum allowed values in the case of Se and Cd. However, in the muscle tissue these values were never reached. Comparing both coasts, we can say that the west coast presents higher levels of Pb while the south coast presents enhanced levels of Hg. Copyright © 2007 John Wiley & Sons, Ltd.