bluuebunny/crossref_metadata_2025_split huggingface dataset:
Co‐Conformational Distribution of Nanosized [2]Catenanes Determined by Pulse EPR Measurements
Authors: Jeschke Gunnar , Godt Adelheid 
Published: December 2003

AbstractThe co‐conformational ensembles of three differently sized [2]catenanes were studied by measuring pair correlation functions corresponding to the separation of nitroxide spin labels—one attached to each of the two macrocycles—with the double electron–electron resonance (DEER) experiment. A geometric model for the [2]catenanes was derived that approximates the macrocycles by circles and takes into account the topological constraint. Comparison of the experimental to the theoretically predicted pair correlation functions gives insight into the co‐conformational distribution and the size of the macrocycles. It was found that the macrocycles of the medium‐ and large‐sized catenanes in chloroform are close to fully expanded, while they are partially collapsed in glassyo‐terphenyl. For the small‐sized catenane, moderate interaction between the unsaturated sections of the macrocycles in chloroform is indicated by a slight overrepresentation of short label‐to‐label separations in the pair correlation function.
Size of head phantoms for standard measurements of SAR due to wireless communication devices
Authors: Mochizuki Shoji , Watanabe Soichi , Taki Masao , Yamanaka Yukio , Shirai Hiroshi 
Published: December 2003

AbstractIn recent years, a project on the standardization of measurement methods for the head specific absorption rate (SAR) while using cellular phones has been in progress in Japan, Europe, and the United States. In order to achieve international coordination, it is desirable that head phantoms of the same shape be used in all countries; these are based on statistical data on European and American human sizes. However, the validity of application to the Japanese standard head phantoms which are generally of a larger size than the Japanese human size has not been established. Consequently, SAR measurements are made in this study with head phantoms based on the 90th‐percentile values of the head shape statistics of Europeans and Americans (E/A) and head phantoms based on the average Japanese adult male head shape (JP) in order to investigate the dependence of the head SAR on the phantom size. A numerical simulation is also performed, and the effect of the head phantom size on the current distribution on a cellular phone is also investigated. Based on these studies, it is found that the effect of the head phantom characteristics on the head SAR is small compared to the effect of the position of the cellular phone in the measurements, and that the effect on the current distribution on the cellular phone is also small. It is shown that for all three types of cellular phone models, that is, thick, thin, and folding types, that the E/A phantoms have roughly the same or larger maximum local SAR values than the JP phantoms. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 82–91, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10083
Dynamic DR election for generating the multicast tree in PIM‐SM
Authors: Matsuzawa Tomofumi , Nakayama Masaya 
Published: December 2003

AbstractIn IP multicast streaming, PIM‐SM (protocol independent multicast sparse‐mode) is now becoming the mainstream. However, it may happen that the optimal tree cannot be generated, depending on the location of the DR (designated router, which is the router used to generate the tree and so on when there are multiple PIM‐SM routers in the segment) in some special topology. The means of handling such a situation is described only ambiguously in the PIM‐SM specification. Consequently, various problems now arise in implementation. This paper considers the dynamic determination of a DR that can generate the optimal tree even in such a special topology, and proposes a new additional protocol. Tree generation for various topologies is examined for the proposed method and the existing implementation, and it is shown that the proposed method is effective for any existing topology. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 65–72, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10105
A QoS control method for MPEG video with an RTP monitoring agent for mobile streaming service
Authors: Yoshimura Takeshi , Ohya Tomoyuki , Kawahara Toshiro , Etoh Minoru 
Published: December 2003

AbstractThe authors propose a MPEG video quality control method for mobile streaming environment, in which the network agent called “RTP monitoring agent” is used. The RTP monitoring agent is placed at the border between the wired core network and the radio link. It feeds back QoS information, which contains the packet loss or delay fluctuation (jitter) observed by the agent itself, to the streaming server. Based on the feedback information sent from the monitoring agent and the feedback information sent from the streaming terminal, the streaming server decides whether the QoS degradation is due to network congestion or an error in the radio link. It then adjusts the transmission rate in the case of network congestion, and the packet loss immunity in the case of an error in the radio link. This paper also discusses a quality control method in MPEG video streaming that involves controlling file switching as well as the I‐picture insertion interval and the FEC packet transmission rate. A computer simulation shows that the MPEG video receiving quality is improved more in the quality control method using RTP monitoring agent than in the conventional rate control method. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 54–64, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10106
Quasi‐optical antenna‐mixer array composed of a magnetic loop antenna operated at 10‐GHz band
Authors: Saito Hiroyuki , Nishimura Toshihiko , Yamamoto Manabu , Itoh Kiyohiko 
Published: December 2003

AbstractThe quasi‐optical antenna‐mixer is a receiving system that spatially receives RF signals and local oscillator (LO) signals and at the same time converts the RF signals to intermediate (IF) frequency signals. The line transmission loss, which causes a problem at millimeter wave frequencies, can be suppressed. In this paper, test fabrication and measurement of a quasi‐optical antenna‐mixer array receiving RF and LO signals with a magnetic loop antenna are carried out at 10 GHz and quasi‐optical mixing is shown to be possible. A two‐dimensional array antenna using this element is proposed. Its receiving characteristics are theoretically predicted. By changing the illumination angle or frequency of the LO, it is found that the receiving direction of the RF can be scanned. In addition, the suppression of RF and LO signals appearing at the output end is demonstrated. An experiment with a two‐dimensional array consisting of eight elements of quasi‐optical antenna‐mixers is carried out and the validity of the proposal is confirmed. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 45–53, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10114
A scalable service control platform based on the locality of database access requests in the mobile communication network
Authors: Ogawa Takeshi , Masuda Etsuo 
Published: December 2003

AbstractIn regard to the scalable service control platform needed for realization of future mobile communication service, a new method of efficiently accessing distributed databases (DB) is proposed. Previously, as an access system plan to distributed DBs, a unicast‐type system in which the access request to a DB received from the network is transferred to the destination DB (System A) and a multicast system with multicast delivery (System B) have been proposed. In the former, the increased size of the destination decision table puts pressure on main memory. In the latter, multicast communication applies pressure every time on processor process capacity. Hence, sufficient scalability has not been obtained in either method. In the present paper, the existence of locality in the requirement for DB access among users is recognized. A hybrid system (System C) is proposed here in which unicast communication is applied for access by a few users with high access frequency, but multicast communication is used for access by the other, majority users. A system control parameter is introduced to select these communication methods. By choosing the value of this parameter optimally, the user accommodation limits in the conventional system are resolved. It is shown quantitatively that operation with a minimum amount of equipment is possible in a wide accommodation range. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 1–15, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10164
Time‐domain analysis of arc voltage and electromagnetic noise caused by opening arc discharge between carbon and copper contacts
Authors: Koizumi Toshiaki , Takahashi Kumio , Ebara Yasuo , Sone Hideaki , Nemoto Yosiaki 
Published: December 2003

AbstractIn small commutation motors, arc discharges are generated between the brushes (carbon) and commutators (copper) in opposing positions, accompanied by electromagnetic noise. An arc discharge is produced both between the brush and commutator (Cu cathode) and between the commutator and brush (C cathode), and these two phenomena with different polarities cannot be separately observed from outside. In this investigation the arc discharges of different current polarities and their associated noise characteristics are analyzed. Experiments are performed with different opposing electrodes, consisting of C and Cu. The opening voltage is 40 V DC. The current in the closed state is 2 A. The load is an inductance of 0.85 mH. The arc voltage and noise when the electrical contacts are opened in both the Cu cathode and C cathode cases are analyzed as time series. It is found that the maximum noise level in each operation is about 20 dB higher for the Cu cathode case than for the C cathode case. The time of maximum noise generation in each operation is close to the time of arc extinction for the Cu cathode case but is in the middle of the arc discharge for the C cathode case. The time derivative of the voltage waveform near arc extinction and the amplitude of the noise waveform before detection are larger in the Cu cathode case than in the C cathode case. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(4): 92–99, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1188
Characterization of eutectic mixtures in different natural fat blends by thermal analysis
Authors: Solís‐Fuentes Julio A. , Durán‐de‐Bazúa Carmen 
Published: December 2003

AbstractSamples of cacao butter (CB), mango seed almond fat (Mangifera indica var. Manila) (MAF), and zapote mamey seed almond fat (Pouteria sapota) (ZMAF), were analyzed for their fatty acid composition and were mixed according to a 3‐factor simplex‐lattice design. Mixtures were stabilized, their fusion and crystallization thermal behavior, and solid fat contents were evaluated using differential scanning calorimetry. Ternary phase behavior was analyzed with isosolid diagrams. Results showed that the main fatty acids in the fats were oleic, stearic, and palmitic acids: CB: 31.1, 35.5, and 27.8%; MAF: 37.5, 42.6 and 9.9%, and ZMAF: 50.0, 27.2 and 12.0%, respectively. Fusion behavior showed a single curve with only one maximum and one small shoulder for CB and MAF, and three maximum points for ZMAF. Crystallization was also a single curve with only one maximum for the three fats. Solid fat contents at 21.1 °C were: CB: 87.5; MAF: 68.5 and ZMAF: 6.6%. Ternary phase behavior showed that these fats can support preparation of mixtures with different compositions that could become equivalent to cocoa butter for use in alimentary, pharmaceutical, and cosmetic industries.
A gas chromatography‐mass spectrometry method for the detection of adipocere in grave soils
Authors: Forbes Shari L. , Keegan Jim , Stuart Barbara H. , Dent Boyd B. 
Published: December 2003

AbstractAdipocere refers to a decomposition product, which forms due to the post‐mortem conversion of adipose tissue into a lipid mixture. During the conversion process, triglycerides present in the adipose tissue convert to free fatty acids via hydrolysis. Under the right conditions, hydrogenation of the free fatty acids will yield adipocere, which is chiefly comprised of saturated fatty acids. In a burial environment, adipocere may form macroscopically on the decomposing remains, but may also leach into the surrounding soil. This paper describes the development of a gas chromatography‐mass spectrometry method which allows for the quantitative analysis of trace levels of adipocere in grave soils.
Effect of the extraction and bleaching processes on jojoba (Simmondsia chinensis) wax quality
Authors: Tobares Lorena , Guzmán Carlos , Maestri Damián 
Published: December 2003

AbstractThe aim of the work was to evaluate the effect of extraction method and bleaching on the quality of jojoba waxes from Argentina. Jojoba waxes obtained by cold pressing, Golden wax (expeller‐pressed wax) and Lite wax (bleached wax) were analyzed using standard methods adopted as recommended practices by the American Oil Chemists Society. Physical parameters, fatty acid and alcohol compositions were unchanged among waxes. Cold‐pressed wax was noteworthy by its lower peroxide value, higher amounts of tocopherol and total phenol contents. Accordingly, it presented the best oxidative stability. Bleaching caused a strong decrease in both tocopherol and phenol contents; consequently the bleached wax showed poor oxidative stability.
Capillary GLC: a robust method to characterise the triglyceride profile of cocoa butter — results of an intercomparison study
Authors: Buchgraber Manuela , Ulberth Franz , Anklam Elke 
Published: December 2003

AbstractThe results of a method intercomparison study, in which 13 laboratories applied high‐temperature capillary GLC on fused‐silica columns coated with medium‐polarity stationary phases to determine the triglyceride profile of cocoa butter, are reported. The participants did not apply a uniform GLC procedure based on a standard method, but were requested to use their own methodology. However, certain requirements relating to the separation efficiency and the accuracy, had to be fulfilled. The relative standard deviation of the reproducibility was less than 5% for the major triglyceride components of cocoa butter. The results of the present study indicate that neither the type of capillary column employed nor sample injection techniques or other chromatographic conditions influenced to a measurable degree the agreement of results between the participating laboratories. Therefore, we conclude that high‐temperature capillary GLC is a robust and reliable technique for the characterisation of cocoa butter by determining its triglyceride pattern.
Fuel Cell Vehicle Simulation – Part 1: Benchmarking Available Fuel Cell Vehicle Simulation Tools
Authors: Hauer K.H. , Moore R.M. 
Published: December 2003

AbstractFuel cell vehicle simulation is one method for systematic and fast investigation of the different vehicle options (fuel choice, hybridization, reformer technologies). However, a sufficient modeling program, capable of modeling the different design options, is not available today. Modern simulation programs should be capable of serving as tools for analysis as well as development. Shortfalls of the existing programs, initially developed for internal combustion engine hybrid vehicles, are: (i)Insufficient modeling of transient characteristics; (ii) Insufficient modeling of the fuel cells system; (iii) Insufficient modeling of advanced hybrid systems; (iv) Employment of a non‐causal (backwards looking) structure; (v) Significant shortcomings in the area of controls.In the area of analysis, a modeling tool for fuel cell vehicles needs to address the transient dynamic interaction between the electric drive train and the fuel cell system. Especially for vehicles with slow responding on‐board fuel processor, this interaction is very different from the interaction between a battery (as power source) and an electric drive train in an electric vehicle design. Non‐transient modeling leads to inaccurate predictions of vehicle performance and fuel consumption. When applied in the area of development, the existing programs do not support the employment of newer techniques, such as rapid prototyping. This is because the program structure merges control algorithms and component models, or different control algorithms (from different components) are lumped together in one single control block and not assigned to individual components as they are in real vehicles. In both cases, the transfer of control algorithms from the model into existing hardware is not possible. This paper is the first part of a three part series and benchmarks the “state of the art” of existing programs. The second paper introduces a new simulation program, which tries to overcome existing barriers. Specifically it explicitly recognizes the dynamic interaction between fuel cell system, drive train and optional additional energy storage.
Hydrogen Automobile Heads Toward Series Production HydroGen3 Puts Fuel Cells on the Road
Authors: Winter U. , Herrmann M. 
Published: December 2003

AbstractGeneral Motor's concept vehicle HydroGen3, based on the Opel Zafira production model, represents the third generation of fuel cell concept vehicles. Groundbreaking new technical and engineering improvements have been reached, e.g. the integration of the latest generation of fuel cell stacks. The fleet demonstrations will start this year. Given the current stage of development at GM/Opel, hydrogen‐powered automobiles could be mass‐produced in about eight years. An efficient fuel cell technology suitable for everyday use is the essential pre‐condition for the development of an alternative propulsion system, which would replace the classic crude oil‐based fuels for the vehicles of the future. However, this technology alone is not sufficient to establish fuel cell automobiles as viable substitutes for conventional vehicles with gasoline and diesel engines. Factors such as purchase price, safety, engine performance and driving dynamics also play a decisive role for the customer. General Motors (GM) has therefore invested more than one billion dollars to develop an automobile incorporating state‐of‐the‐art fuel cell technology with vehicle characteristics suited to the marketplace. The hydrogen concept vehicle HydroGen3 (Figure 1) marks the newest and most comprehensive advance made by GM/Opel on the road to fuel cell vehicle market readiness. Test drives conducted by an international group of expert journalists at the Grand‐Prix course in Monte Carlo in December 2002 confirmed that the HydroGen3 has brought mass production of hydrogen‐fuelled automobiles within reach.
Hydrogen for the Mobility of the Future Results of GM/Opel's Well‐to‐Wheel Studies in North America and Europe
Authors: Winter U. , Weidner H. 
Published: December 2003

AbstractGeneral Motors conducted two well‐to‐wheel studies for fundamental clarification on the question of which is the cleanest and most environmentally sustainable source of energy for the mobility of the future. In both studies the complete energy chains were analyzed from fuel production using primary energy to the actual consumption of the fuel in the car, i.e. from the well up to the wheels of the vehicle (well to wheel). The aim of the studies was to evaluate total energy consumption on the one hand and, on the other, the total greenhouse gas emissions arising between the production of a fuel and its final use to power an automobile. The results of the studies clearly show that fuel cell vehicles can greatly reduce greenhouse gas emissions from passenger cars or, if they run on hydrogen from renewable energy sources, they can eliminate them entirely. Regenerative fuels, however, will be more expensive than current products. With the fuel cell, because of its superior efficiency (35 – 45% less energy consumption well to wheel), it will be possible to keep individual mobility affordable in the future.
Fuel Cell Vehicle Simulation – Part 3: Modeling of Individual Components and Integration into the Overall Vehicle Model
Authors: Hauer K.H. , Moore R.M. 
Published: December 2003

AbstractThis is the third paper of a three part series on fuel cell vehicle (FCV) simulation. In Part 1 of this series, the existing publicly available models for FCV analysis and simulation were evaluated and the strengths and weaknesses of these models were identified. In Part 2, a new FCV simulation framework (and the methodology behind it) was introduced which focused on overcoming the weaknesses of the benchmarked models. In this third paper, the model framework developed in Part 2 is filled with component models. Specifically, models for the electric drive train, the transmission, a battery system, a dc‐dc‐converter and a fuel cell system with the associated control units are developed and described. An indirect‐methanol fuel cell system, with all of its subsystems, is illustrated in this paper, as an example of the process and implementation of a fuel cell system model. This example fuel cell system is characterised in both steady‐state and dynamic terms by numerical simulation, and is also used to illustrate the system integration required for a complete FCV simulation model.
Development of an Auxiliary Power Unit with Solid Oxide Fuel Cells for Automotive Applications
Authors: Lamp P. , Tachtler J. , Finkenwirth O. , Mukerjee S. , Shaffer S. 
Published: December 2003

AbstractDelphi Corporation and the BMW Group are developing Solid Oxide Fuel Cell (SOFC) technology for application in the automotive industry as an on‐board Auxiliary Power Unit (APU). Delphi is part of the US‐DOE SECA initiative and is working with Battelle to develop SOFC for multiple applications including the automotive market. BMW is a leading customer in the development and is a key player in the introduction of new technologies to the market.The APU provides significant customer benefits with regard to the availability of electrical functions, in particular engine‐independent functions such as auxiliary air conditioning. In addition, it has the potential to save fuel due to the high efficiency of producing electricity.The focus of this development is to apply the APU to the present car generation, i.e. using gasoline as fuel. This makes SOFC the most suitable fuel cell technology for this application, being able to utilize the high CO containing reformate expected from higher hydrocarbons without further gas purification steps. However, key challenges exist in using the SOFC technology to meet the particular needs for this automotive application. These challenges include rapid start‐up, large number of thermal cycles, compact system, low cost and others. In this paper, the status of the Delphi/BMW APU and recent progress in the SOFC development will be reviewed.
Cooling Modules for Vehicles with a Fuel Cell Drive
Authors: Rogg S. , Höglinger M. , Zwittig E. , Pfender C. , Kaiser W. , Heckenberger T. 
Published: December 2003

AbstractIn spite of the high efficiency of fuel cell drives for vehicles, cooling is a key problem. The present article reveals the reasons for cooling limits and their physical causes. This leads to deductions about what kind of actions can be taken to increase cooling performance. The implementation of these measures is demonstrated by means of examples of cooling modules for vehicles with a fuel cell drive.