Measured Results (measured + result)

Distribution by Scientific Domains


Selected Abstracts


Suppression of electromagnetic radiation noise from wireless modules in the millimeter-wave band by means of alumina containing carbon black

ELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 10 2010
Yasuharu Takase
Abstract Unwanted electromagnetic (EM) radiation generated from wireless modules in the millimeter-wave band used for car radar creates errors and results in performance degradation of electronic equipment. In this paper, to reduce these unwanted EM waves, an optimal design to add the function of EM wave absorption to the lid for the module is examined. Alumina-containing carbon black is used as a wave absorption material for the lid. Absorption of 20 dB or more is obtained as a measured result with the cover added for EM wave absorption at 60 GHz. The wireless module was also analyzed in the millimeter-wave band with the designed material used for the lid. The radiation and the reflection of electric power were greatly reduced by the loss electric power from the lid. Therefore, effective data for suppressing unwanted EM radiation noise from wireless modules in the millimeter-wave band can be provided. © 2010 Wiley Periodicals, Inc. Electron Comm Jpn, 93(10): 25,33, 2010; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.10216 3 [source]


Improvement of the resonant characteristics of the short-ended stub by the optimal arrangement positions of via-holes

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2007
Ifong Wu
Abstract A method for improving the resonant characteristic of the short-ended stub is proposed by locating the via-holes on the optimal position on the ground. In the first step, the optimal length of the stub at 1 GHz is evaluated by comparing the numerical calculated result and the measured result (used the fabricated stub), which is based on the theoretical calculation, and the resonant characteristics shifted to the lower frequency regions. These shifting phenomena of the resonant characteristics are caused by the via-hole. When the via-hole is arranged on the substrate, the via-hole becomes part of the stub, and the length of the stub becomes longer than the theoretical calculation. As a result, a good agreement between both results is achieved when the stub length is 27.43 mm, and hence the optimal length of the stub is confirmed. For the second step, the optimal arrangement position of the via-holes is evaluated by using current distribution on the stub model. In this study, we applied the Green's function method to obtain the current distribution. The improvement of resonant characteristic is achieved by arranging the via-holes on the place where the currents concentrate. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 642,645, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22202 [source]


Hybrid platform for vibration control of high-tech equipment in buildings subject to ground motion.

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2003
Part 2: analysis
Abstract The experimental results of using a hybrid platform to mitigate vibration of a batch of high-tech equipment installed in a building subject to nearby traffic-induced ground motion have been presented and discussed in the companion paper. Based on the identified dynamic properties of both the building and the platform, this paper first establishes an analytical model for hybrid control of the building-platform system subject to ground motion in terms of the absolute co-ordinate to facilitate the absolute velocity feedback control strategy used in the experiment. The traffic-induced ground motion used in the experiment is then employed as input to the analytical model to compute the dynamic response of the building-platform system. The computed results are compared with the measured results, and the comparison is found to be satisfactory. Based on the verified analytical model, coupling effects between the building and platform are then investigated. A parametric study is finally conducted to further assess the performance of both passive and hybrid platforms at microvibration level. The analytical study shows that the dynamic interaction between the building and platform should be taken into consideration. The hybrid control is effective in reducing both velocity response and drift of the platform/high-tech equipment at microvibration level with reasonable control force. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Sleeve monopole on a circular ground-plane

INTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2003
Zhongxiang Shen
Abstract This paper presents a modal-expansion analysis of a sleeve monopole antenna on a finite ground-plane. Two perfectly conducting plates (one above the monopole and the other under the ground-plane) are introduced to confine the modeling region and to facilitate the modal-expansion analysis. The resulting guided-wave structure is then divided into a number of regions and the electromagnetic field components in each region are expanded into the summation of its modal functions. The surface current distribution on the monopole and the antenna's input impedance and radiation pattern are obtained by finding the expansion coefficients through matching the tangential field components across the regional interfaces. Calculated results by the modal-expansion method agree well with measured results for the return loss of a sleeve monopole fed through a circular ground-plane by a coaxial probe. Numerical results for the surface current distribution, input impedance, and radiation pattern of a sleeve monopole on a circular ground plane are presented and discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Edge feeding of circular patch microstrip antennas

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 2 2001
B. S. Rao
Abstract Edge feeding of a circular patch antenna by a microstrip line has been achieved by utilizing the circumferential variation of the field which is fixed by loading the patch. However, loading splits the degenerate modes and gives rise to cross-polarization. Three different techniques are presented to analyze the loaded circular patch antenna. Comparison with the measured results for input impedance and radiation patterns shows good agreement. The concept used here is very general and can be applied to the edge feeding of any ring antenna. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 74,85, 2001. [source]


Laser monitoring of non-Newtonian liquids during dip coating

AICHE JOURNAL, Issue 12 2009
Alexandre F. Michels
Abstract Dip coated films, widely used in the coating industry, are usually measured by capacitive methods with micrometric precision. In this work, interferometric determination of thickness evolution in real time, for the first time to our best knowledge, is applied to volatile non-Newtonian liquids with several viscosities and distinct dip withdrawing speeds. Thickness evolution during the process depends on time as predicted by a power law model. Comparison with measured results (uncertainty of ± 0.007 ,m) showed very good agreement after initial steps of the process. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]


The role that bond coat depletion of aluminum has on the lifetime of APS-TBC under oxidizing conditions

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 7 2008
D. Renusch
Abstract Bond coat oxidation as well as bond coat depletion of Al are still believed to be a major degradation mechanism with respect to the lifetime of thermal barrier coating (TBC) systems. In this study the top coat lifetime is described as being limited by both bond coat depletion of Al and mechanical failure of the top coat. The empirical results are introduced by considering three spallation cases, namely, Al depletion failure, thermal fatigue failure, and thermal aging failure. Al depletion failure occurs when the Al content within the bond coat reaches a critical value. In this paper bond coat depletion of Al is modeled by considering the diffusion of Al into both the thermally grown oxide (TGO) and substrate. The diffusion model results are compared to Al concentration profiles measured with an electron beam microprobe. These measured results are from oxidized air plasma sprayed TBC systems (APS-TBC) with vacuum plasma sprayed (VPS) bond coats for exposures up to 5000 h in the temperature range of 950,1100,°C. This paper focuses on the Al depletion failure and how it relates to top coat spallation. [source]


High-performance UWB filter with a controllable notched band

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2010
Chun-Ping Chen
Abstract This article presents a design of a high-performance ultra-wideband (UWB) bandpass filter with a controllable notched band. Firstly, a UWB filter consisting of a stepped-impedance resonator (SIR) and two shunt short-circuited stubs is synthesized. Then, a narrow controllable notched band is introduced by a coupled external SIR. To be highlighted as an attractive advantage, as the characteristics of the UWB filter are not deteriorated by the placement of the external resonator, no further adjustments is needed for the synthesized UWB filter in this design. As an example, an (Federal Communications Commission) FCC UWB filter with a WLAN notch band is designed, simulated, and fabricated. A good agreement between the measured results and predicted ones validates the newly proposed design scheme and the filter prototype. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1842,1846, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25354 [source]


A new impedance match method to improve efficiency of LINC with Chireix combiner

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2010
Tao Ni
Abstract In this article, we propose a new impedance match method in serial Chireix combiner to improve the efficiency of Linear amplification with Nonlinear Components (LINC) amplifier. Based on the impedance characteristics of the serial Chireix combiner, two transmission lines are added between power amplifiers (PAs) and Chireix combiner in LINC. For experimental verification, the PAs and combiner are implemented and tested. From the measured results, this method is proved available for improving efficiency of LINC, and convenient for design as well as tuning work. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1418,1421, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25205 [source]


Compact dual-mode bandpass filter using arrow-shaped slot resonator

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2009
Youngje Sung
Abstract A novel design of a compact bandpass ring slot filter for achieving dual-mode operation is proposed and experimentally studied. By using an arrow-shaped slot structure as a resonator, the resonant frequency of the proposed filter is significantly lowered, which can lead to a large filter size reduction for a fixed frequency operation. Two degenerate modes are achieved by loading with proper asymmetry, which can be placed at the corner of diagonals. A prototype of the proposed design is implemented and measured. From the measured results, the proposed filter has about 5.2% bandwidth at the center frequency of 0.97 GHz and a minimum insertion loss of 1.07 dB within passband. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2989,2991, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24809 [source]


Design of a compact branch-line coupler using capacitance loading

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2009
Tao Jing
Abstract This article presents a compact branch-line coupler (BLC) for balanced-type circuit application. It was designed by utilizing cascading multisection and capacitance-loading technique for bandwidth increase and size reduction individually. The proposed BLC was simulated and fabricated. Its physical length reduces by 28.7%, while it performs as good as the conventional one. The simulated and the measured results have a good agreement. The method is valid for compact and good performance BLC design. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 198,200, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23992 [source]


A novel bandpass filter based on complementary split rings resonators and substrate integrated waveguide

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2008
Wenquan Che
Abstract One novel bandpass filter implemented with combination of two different structures-complementary split rings resonators (CSRRs) and substrate integrated waveguide (SIW) is proposed in this article. Several CSRRs are etched on the surface of SIW to form the stopband with very sharp rejection. One prototype was fabricated, the measured results indicate 30% passband (at ,15 dB return loss), the rejection band ranges from 6.4 GHz to 7.8 GHz, about 20% bandwidth at ,20 dB rejection, the maximum rejection even reaches 50 dB. The rejection skirt is very sharp, only 18 MHz. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 699,701, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23182 [source]


A high-efficiency class-E power amplifier using SiC MESFET

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2007
Yong-Sub Lee
Abstract This article reports a high efficiency class-E power amplifier using a SiC MESFET, which is designed and tested at 2.14 GHz. To improve output power and efficiency by suppressing harmonic powers, an output matching circuit using the transmission lines is used. From measured results for a single tone, the harmonic power levels are maintained below ,58 dBc at a whole output power level. The peak power-added efficiency of 72.3% with a power gain of 10.27 dB is achieved at an output power of 40.27 dBm. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1447,1449, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI.10.1002/mop.22455 [source]


Broad-band power divider based on radial waveguide

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2007
Kaijun Song
Abstract A broad-band power divider using coaxial probes and a radial waveguide is presented. The simple modeling of this power divider and design method based on equivalent circuits has been developed. A four-way radial waveguide power divider has been designed, fabricated, and measured. Close agreement is obtained between the measured results and the simulated results. The measured 15-dB return loss bandwidth of the broad-band multiple-port structure is demonstrated to be 81.5% and its 0.5-dB insertion loss bandwidth 84.6%. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 595,597, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22216 [source]


A self-similar fractal electromagnetic band-gap structure in the power plane with broadband suppression of ground bounce noise

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2007
Peng Zhou
Abstract In this paper, a self-similar fractal electromagnetic band-gap structure with "L-Cross " slots is proposed and designed in the power plane to suppress the ground bounce noise in high-speed circuits. Both the simulation and the measured results with good agreement with each other show a low onset band stop frequency of 500 MHz and a broad stop band of about 4 GHz. When combining the structure with decoupling capacitor walls at the boundary of the power plane, a broadband GBN suppression from DC to 6 GHz can be obtained. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 190,192, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22063 [source]


Novel filter using composite right/left-handed transmission line

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2006
JiuSheng Li
Abstract A novel filter using composite right/left-handed (CRLH) transmission line (TL) unit cells is designed, fabricated, and measured. After properly designing the parameters of the capacitors and the inductors, we have generated a narrow bandpass filter. The simulation results show that the bandpass filter with 4 CRLH TL unit cells has very small loss in the passband and very sharp transitions at the edges of the passband. The performances of the proposed filter are demonstrated by measured results, which are in good agreement with the simulation ones. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2013,2015, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21860 [source]


Variations in Grain Size Analysis with a Time-of-Transition Laser Sizer (Galai CIS-50) using a Gravitational Flow System

PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 6 2004
Björn Bohling
Abstract This study deals with grain size analysis with a Laser Sizer Galai CIS-50. This device utilizes the time-of-transition method and is equipped with a module for measurements in the range 0.5 to 150,,m along with a gravitational flow system. Experiments were conducted using natural marine sediments. The aim was to determine possible explanations for discrepancies in the measured results that occurred between different operators of the Galai CIS-50. These discrepancies may be due to differences in the technique of inserting a sub-sample into the measurement system. Furthermore, the influence of the sample concentration and the flow velocity in the device's liquid flow cell is considered, since these factors can act as potential sources of inaccuracies and errors in the experimental setup. Strong variations in the results occurred, which were mainly due to problems in the detection of particles >20,,m. In the range>20,,m gaps appeared in the registration of the size distribution. An improvement in reproducibility was achieved by using a pipette instead of a beaker for the insertion step. Nevertheless, the standard deviation for mean grain sizes of natural marine sediments obtained with the Galai CIS-50 is still about 20%. [source]


Ermittlung des Wasserdampfdiffusionswiderstandes von Baustoffen in Abhängigkeit von der Baustofftemperatur

BAUPHYSIK, Issue 2 2009
Nicol Pötzsch Dipl.-Ing. (FH)
Feuchte; Versuche Abstract Analog zu dem in DIN EN ISO 12572 beschriebenen Messverfahren zur Ermittlung des Wasserdampfdiffusionswiderstandswertes , von Baustoffen, wurden Untersuchungen zum Einfluss der Temperatur auf den Diffusionswiderstand durchgeführt. Die Untersuchungen erfolgten sequenziell bei ausgewählten Temperaturstufen von ,10, ,5, 0, 10 sowie 50 °C. Untersucht wurden zwei Holzwerkstoffe (MDF, OSB), ein Wärmedämm-Verbundsystem, ein Putzsystem und ein EPS-Dämmstoff. Anhand der Ergebnisse kann darauf geschlossen werden, dass die Temperatur innerhalb der untersuchten Grenzen einen Einfluss auf den Materialkennwert , hat. Determination of the water vapour diffusion permeability of building materials in dependency on the temperature. Investigations concerning the correlation between the water vapour diffusion permeability (, -value) and the temperature were done at two wood based panels (MDF and OSB), an external thermal insulation compound system, a plaster system and an EPS-insulation. The investigations were made by analogy to the measurement method described in ISO 12572 but at the chosen temperature levels from ,10, ,5, 0, 10 up to 50 °C. Based on the measured results, it can be concluded, that the , -value is influenced by the temperature. [source]


Erfahrungen mit dem Spannungs-Verformungsverhalten von mit Geogittern bewehrten Stützkonstruktionen

BAUTECHNIK, Issue 11 2007
Florian Bussert Dr.-Ing.
Seit mehreren Jahrzehnten hat sich der Bau geokunststoffbewehrter Erdkörper erfolgreich bewährt. Die Errichtung der Stützkonstruktionen auf stark wechselndem oder gering tragfähigem Untergrund, bei hohen Verkehrslasten oder großen Konstruktionshöhen hat sich vielfach als äußerst ökonomische und ökologische Alternative zu klassischen Bauweisen bewiesen. Um Erfahrungen mit einer neuen Bauweise zu sammeln, wird häufig die sogenannte Beobachtungsmethode angewandt, d.h., das Spannungs-Verformungs-Verhalten wird sowohl während der Erstellung als auch in der ersten Nutzungsphase des Bauwerks messtechnisch ermittelt. Aus diesen Messergebnissen wird deutlich, dass auch bei hoher Beanspruchung der Konstruktionen die Gesamtverformungen kleiner sind als erwartet. Vor allem die gemessenen Dehnungen der Geogitter sind kleiner als die berechneten Werte. Das derzeit verwendete Konzept zur Abschätzung der Dehnungen scheint damit weit entfernt vom tatsächlichen Verhalten derartiger Konstruktionen. Die Erfahrungen von ausgeführten Baumaßnahmen werden vorgestellt und die Ergebnisse diskutiert. Experiences with the tension deformation behaviour of retaining structures reinforced with geosynthetics. Since several decades the application of geosynthetic-reinforced earth bodies successfully worked. The establishment of the retaining structures on strongly changing or small load-carrying underground, with high live loads or large construction heights proved itself often as extremely economic and ecological alternative to classical building methods. In order to gain experiences with a new building method, frequently the so-called observation method is used, which means the stress-deformation behaviour becomes both while the construction and the first utilization phase of the building is determined by measuring techniques. From these results of measurement it becomes clear that also when high loaded the total deformations of the constructions are smaller than expected. From all the measured results the deformations of the geosynthetics are smaller than the analyzed values. The concept for the estimation of the deformations, used at present, seems far thereby from the actual behaviour of such constructions. The experiences of completed structures are presented and the results are discussed. [source]


Application of Residence Time Distribution for Measuring the Fluid Velocity and Dispersion Coefficient

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 1 2007
W. Zhang
Abstract Most studies on residence time distribution (RTD) have focused on the tail of the RTD curve, and very little attention has been paid to the effect of white noise on the measured results. The aim of this work is to study the effect of white noise on the calculated parameters with different data processing methods. The anti-disturbance abilities of the moment method and the least squares method are compared. The results show that the anti-disturbance ability of the least squares method was better than that of the moment method. As a result of peak overlapping in the RTD curve of a loop reactor, the moment method cannot be used to calculate the fluid velocity and dispersion coefficient. Experiments show that the least squares method is still applicable in a loop reactor. [source]


Audit of stapedectomy results in a district general hospital

CLINICAL OTOLARYNGOLOGY, Issue 4 2002
A. Banerjee
We report a series of 100 stapes operations performed for otosclerosis. The problems in reporting the results of stapedectomies are discussed. The audit showed a difference in the measured results between two consultants. As a result, the consultant with the worse outcome chose to stop operating on patients with otosclerosis. The advantages and disadvantages of a single surgeon performing all the cases are discussed. We advocate a central registry of all surgeons performing stapes surgery to allow periodic national comparative audits. [source]