bluuebunny/crossref_metadata_2025 huggingface dataset:
The Relative Performance of NDIR-based Sensors in the Near Real-time Analysis of CO2 in Air
Authors: Pandey Sudhir  Kumar , Kim Ki-Hyun
Published: October 2008

In this study, the reliability of NDIR-based sensors was explored by evaluatingthe comparability between measurement systems in the near real-time analysis of CO2. Forthis purpose, replicate analyses were performed using sensors of two different model types(H-550 and B-530, ELT Company, Korea). Three replicate data of each sensor typecollected continuously by side-by-side analysis in three second intervals (a duration of 304hour) were evaluated for the relative performance of NDIR sensors. The reproducibility ofsensors, when assessed by relative standard error (RSE %) values of all sensor units,showed moderate changes with time with the overall mean of 2.33%. When CO2measurements from all NDIR sensor units were evaluated by correlation analysis, theresults showed strong comparability, regardless of the model type. The overall results ofthis study suggest that NDIR sensors are reliable enough to produce highly comparabledata at least in a relative sense.
High Resolution Marine Magnetic Survey of Shallow Water Littoral Area
Authors: Weiss Eyal , Ginzburg Boris , Cohen Tsuriel  Ram , Zafrir Hovav , Alimi Roger , Salomonski Nizan , Sharvit Jacob
Published: October 2008

The purpose of this paper is to present a system developed for detection andaccurate mapping of ferro-metallic objects buried below the seabed in shallow waters. Thesystem comprises a precise magnetic gradiometer and navigation subsystem, both installedon a non-magnetic catamaran towed by a low-magnetic interfering boat. In addition wepresent the results of a marine survey of a near-shore area in the vicinity of Atlit, a townsituated on the Mediterranean coast of Israel, about 15 km south of Haifa. The primarypurpose of the survey was to search for a Harvard airplane that crashed into the sea in 1960.A magnetic map of the survey area (3.5 km2 on a 0.5 m grid) was created revealing theanomalies at sub-meter accuracy. For each investigated target location a correspondingferro-metallic item was dug out, one of which turned to be very similar to a part of thecrashed airplane. The accuracy of location was confirmed by matching the position of theactual dug artifacts with the magnetic map within a range of ± 1 m, in a water depth of 9 m.
Modeling of Photoinduced Deformation in Silicon Microcantilever
Authors: Guo Yu-Lin , Zhou Jia , Huang Yiping , Bao MinHang
Published: October 2008

A model for prediction the photostriction effect in silicon microcantilevers is built up based on the fundamentals of mechanics and semiconductor physics. By considering the spatial distribution and surface recombination of photoinduced carriers in silicon, the model interprets the cause of the photoinduced bending. The results from our model much more closely approximate the experimental values than the former model built up by Datskos, Rajic and Datskou [1](APL, Vol.73 (1998) No.16, pp 3219-2321), represented by the reduction of the error between calculation and measurement from 25 times to 0.85 times.
Reliability of a MEMS Actuator Improved by Spring Corner Designs and Reshaped Driving Waveforms
Authors: Hsieh Hsin-Ta , Su Guo-Dung John
Published: October 2008

In this paper, we report spring corner designs and driving waveforms to improve the reliability for a MEMS (Micro-Electro-Mechanical System) actuator. In order to prevent the stiction problems, no stopper or damping absorber is adopted. Therefore, an actuator could travel long distance by electromagnetic force without any object in moving path to absorb excess momentum. Due to long displacement and large mass, springs of MEMS actuators tend to crack from weak points with high stress concentration and this situation degrades reliability performance. Stress distribution over different spring designs were simulated and a serpentine spring with circular and wide corner design was chosen due to its low stress concentration. This design has smaller stress concentration versus displacement. Furthermore, the resonant frequencies are removed from the driving waveform based on the analysis of discrete Fourier transfer function. The reshaped waveform not only shortens actuator switching time, but also ensures that the spring is in a small displacement region without overshooting so that the maximum stress is kept below 200 MPa. The experimental results show that the MEMS device designed by theses principles can survive 500 g (gravity acceleration) shock test and pass 150 million switching cycles without failure.
Cross-Reactive Sensor Array for Metal Ion Sensing Based on Fluorescent SAMs
Authors: Basabe-Desmonts Lourdes , Van der Baan Frederieke , Zimmerman Rebecca S. , Reinhoudt David N. , Crego-Calama Mercedes
Published: October 2008

Fluorescent self assembled monolayers (SAMs) on glass were previouslydeveloped in our group as new sensing materials for metal ions. These fluorescent SAMs arecomprised by fluorophores and small molecules sequentially deposited on a monolayer onglass. The preorganization provided by the surface avoids the need for complex receptordesign, allowing for a combinatorial approach to sensing systems based on small molecules.Now we show the fabrication of an effective microarray for the screening of metal ions andthe properties of the sensing SAMs. A collection of fluorescent sensing SAMs wasgenerated by combinatorial methods and immobilized on the glass surfaces of a custom-made 140 well microtiter-plate. The resulting libraries are easily measured and show variedresponses to a series cations such as Cu2+ , Co2+ , Pb2+ , Ca2+ and Zn2+ . These surfaces are notdesigned to complex selectively a unique analyte but rather they are intended to producefingerprint type responses to a range of analytes by less specific interactions. The unselectiveresponses of the library to the presence of different cations generate a characteristic patternfor each analyte, a “finger print” response.
A Wireless, Passive Sensor for Quantifying Packaged Food Quality
Authors: Tan Ee  Lim , Ng Wen  Ni , Shao Ranyuan , Pereles Brandon  D. , Ong Keat Ghee
Published: October 2008

This paper describes the fabrication of a wireless, passive sensor based on aninductive-capacitive resonant circuit, and its application for in situ monitoring of thequality of dry, packaged food such as cereals, and fried and baked snacks. The sensor ismade of a planar inductor and capacitor printed on a paper substrate. To monitor foodquality, the sensor is embedded inside the food package by adhering it to the package’sinner wall; its response is remotely detected through a coil connected to a sensor reader. Asfood quality degrades due to increasing humidity inside the package, the paper substrateabsorbs water vapor, changing the capacitor’s capacitance and the sensor’s resonantfrequency. Therefore, the taste quality of the packaged food can be indirectly determined bymeasuring the change in the sensor’s resonant frequency. The novelty of this sensortechnology is its wireless and passive nature, which allows in situ determination of foodquality. In addition, the simple fabrication process and inexpensive sensor material ensure alow sensor cost, thus making this technology economically viable.
Study of the origin of bending induced by bimetallic effect on microcantilever
Authors: Ramos Daniel , Mertens Johann , Calleja Montserrat , Tamayo Javier
Published: October 2008

An analytical model for predicting the deflection and force of a bimaterialcantilever is presented. We introduce the clamping effect characterised by an axial loadupon temperature changes. This new approach predicts a non linear thermal dependence ofcantilever strain. A profilometry technique was used to measure the thermal strain.Comparison with experimental results is used to verify the model. The concordance of theanalytical model presented with experimental measurements is better than 10%
Time Series Forecasting Energy-efficient Organization of Wireless Sensor Networks
Authors: Wang Xue , Ma Jun-Jie , Wang Sheng , Bi Dao-Wei
Published: October 2008

Due to their wide potential applications, wireless sensor networks have recentlyreceived tremendous attention. The strict energy constraints of sensor nodes result in thegreat challenges for energy efficiency. This paper investigates the energy efficiency problemand proposes an energy-efficient organization method with time series forecasting. Theorganization of wireless sensor networks is formulated for target tracking. Target model,multi-sensor model and energy model are defined accordingly. For the target trackingapplication, target localization is achieved by collaborative sensing with multi-sensor fusion.The historical localization results are utilized for adaptive target trajectory forecasting.Empirical mode decomposition is implemented to extract the inherent variation modes in thetime series of a target trajectory. Future target position is derived from autoregressivemoving average (ARMA) models, which forecast the decomposition components,respectively. Moreover, the energy-efficient organization method is presented to enhance theenergy efficiency of wireless sensor networks. The sensor nodes implement sensing tasksaccording to the probability awakening in a distributed manner. When the sensor nodestransfer their observations to achieve data fusion, the routing scheme is obtained by antcolony optimization. Thus, both the operation and communication energy consumption canbe minimized. Experimental results verify that the combination of the ARMA model andempirical mode decomposition can estimate the target position efficiently and energy savingis achieved by the proposed organization method in wireless sensor networks.
Energy-efficient Optimization of Reorganization-Enabled Wireless Sensor Networks
Authors: Wang Xue , Ding Liang , Bi Dao-Wei , Wang Sheng
Published: October 2008

This paper studies the target tracking problem in wireless sensor networkswhere sensor nodes are deployed randomly. To achieve tracking accuracy constrained byenergy consumption, an energy-efficient optimization approach that enablesreorganization of wireless sensor networks is proposed. The approach includes threephases which are related to prediction, localization and recovery, respectively. A particlefilter algorithm is implemented on the sink node to forecast the future movement of thetarget in the first prediction phase. Upon the completion of this phase, the most energyefficient sensor nodes are awakened to collaboratively locate the target. Energy efficiencyis evaluated by the ratio of mutual information to energy consumption. The recoveryphase is needed to improve the robustness of the approach. It is performed when thetarget is missed because of the incorrect predicted target location. In order to recapture thetarget by awakening additional sensor nodes as few as possible, a genetic-algorithm-basedmechanism is introduced to cover the recovery area. We show that the proposed approachhas excellent tracking performance. Moreover, it can efficiently reduce energyconsumption, prolong network lifetime and reduce network overheads.
Measurement of the Mass and Rigidity of Adsorbates on a Microcantilever Sensor
Authors: Ramos Daniel , Calleja Montserrat , Mertens Johann , Zaballos A. , Tamayo Javier
Published: October 2008

When microcantilevers are used in the dynamic mode, the resonance shift uponmaterial adsorption depends on the position of the adsorbate along the microcantilever. Wehave previously described that the adsorbate stiffness needs to be considered in addition toits mass in order to correctly interpret the resonance shift. Here we describe a method thatallows obtaining the Young’s modulus of the adsorbed bacteria derived from themeasurement of the frequency shift when adsorbates are placed close to the clampingregion. As a model system we have used E. Coli bacteria deposited on the cantileversurface by the ink-jet technique. We demonstrate that the correct information aboutadsorbed mass can be extracted by recording the cantilever profile and its resonanceresponse. Also, the position and extent of adsorbates is determined by recording themicrocantilever profile. We use a theoretical model based on the Euler – Bernouilliequation for a beam with both mass and flexural rigidity local increase due to the depositedmaterial.
A Compact Laboratory Spectro-Goniometer (CLabSpeG) to Assess the BRDF of Materials. Presentation, Calibration and Implementation on Fagus sylvatica L. Leaves
Authors: Biliouris Dimitrios , Verstraeten Willem W. , Dutré Phillip , Van Aardt Jan A.N. , Muys Bart , Coppin Pol
Published: October 2008

The design and calibration of a new hyperspectral Compact Laboratory Spectro-Goniometer (CLabSpeG) is presented. CLabSpeG effectively measures the bidirectionalreflectance Factor (BRF) of a sample, using a halogen light source and an AnalyticalSpectral Devices (ASD) spectroradiometer. The apparatus collects 4356 reflectance datareadings covering the spectrum from 350 nm to 2500 nm by independent positioning of thesensor, sample holder, and light source. It has an azimuth and zenith resolution of 30 and15 degrees, respectively. CLabSpeG is used to collect BRF data and extract BidirectionalReflectance Distribution Function (BRDF) data of non-isotropic vegetation elements suchas bark, soil, and leaves. Accurate calibration has ensured robust geometric accuracy of theapparatus, correction for the conicality of the light source, while sufficient radiometricstability and repeatability between measurements are obtained. The bidirectionalreflectance data collection is automated and remotely controlled and takes approximatelytwo and half hours for a BRF measurement cycle over a full hemisphere with 125 cmradius and 2.4 minutes for a single BRF acquisition. A specific protocol for vegetative leafcollection and measurement was established in order to investigate the possibility to extractBRDF values from Fagus sylvatica L. leaves under laboratory conditions. Drying leafeffects induce a reflectance change during the BRF measurements due to the laboratorySensors 2007, 7 1847 illumination source. Therefore, the full hemisphere could not be covered with one leaf. Instead 12 BRF measurements per leaf were acquired covering all azimuth positions for a single light source zenith position. Data are collected in radiance format and reflectance is calculated by dividing the leaf cycle measurement with a radiance cycle of a Spectralon reference panel, multiplied by a Spectralon reflectance correction factor and a factor to correct for the conical effect of the light source. BRF results of measured leaves are presented.
Electrodeposited and Sol-gel Precipitated p-type SrTi1-xFexO3-δ Semiconductors for Gas Sensing
Authors: Sahner Kathy , Gouma Perena , Moos Ralf
Published: October 2008

In the present contribution, three methods for the preparation of nanoscaledSrTi1-xFexO3-δ sensor films for hydrocarbon sensing were investigated. Besides screen-printed thick films based on sol-precipitated nanopowders, two novel synthesis methods,electrospinning and electrospraying, were tested successfully. All of these sensor devicesshowed improved sensor functionality in comparison to conventional microscaled thickfilms. In order to explain the impact of the enhanced surface-to-volume ratio on sensorproperties in a quantitative way, a mechanistic model was applied to micro- and nanoscaleddevices. In contrast to the conventional diffusion-reaction model that has been proposed forn-type semiconducting sensors, it contained novel approaches with respect to themicroscopic mechanism. With very few fit variables, the present model was found torepresent well sensor functionality of p-type conducting SrTi0.8Fe0.2O3-δ films. In additionto the temperature dependency of the sensor response, the effect of the specific surface areaon the sensor response was predicted.
The Investigation of a Shape Memory Alloy Micro-Damper for MEMS Applications
Authors: Pan Qiang , Cho Chongdu
Published: October 2008

Some shape memory alloys like NiTi show noticeable high damping property inpseudoelastic range. Due to its unique characteristics, a NiTi alloy is commonly used forpassive damping applications, in which the energy may be dissipated by the conversion frommechanical to thermal energy. This study presents a shape memory alloy based micro-damper, which exploits the pseudoelasticity of NiTi wires for energy dissipation. Themechanical model and functional principle of the micro-damper are explained in detail.Moreover, the mechanical behavior of NiTi wires subjected to various temperatures, strainrates and strain amplitudes is observed. Resulting from those experimental results, thedamping properties of the micro-damper involving secant stiffness, energy dissipation andloss factor are analyzed. The result indicates the proposed NiTi based micro-damper exhibitsgood energy dissipation ability, compared with conventional materials damper.
Hybrid Integrated Silicon Microfluidic Platform for Fluorescence Based Biodetection
Authors: Chandrasekaran Arvind , Acharya Ashwin , You Jian Liang , Soo Kim Young , Packirisamy Muthukumaran , Stiharu Ion , Darveau André
Published: October 2008

The desideratum to develop a fully integrated Lab-on-a-chip device capable ofrapid specimen detection for high throughput in-situ biomedical diagnoses and Point-of-Care testing applications has called for the integration of some of the novel technologiessuch as the microfluidics, microphotonics, immunoproteomics and Micro ElectroMechanical Systems (MEMS). In the present work, a silicon based microfluidic device hasbeen developed for carrying out fluorescence based immunoassay. By hybrid attachment ofthe microfluidic device with a Spectrometer-on-chip, the feasibility of synthesizing anintegrated Lab-on-a-chip type device for fluorescence based biosensing has beendemonstrated. Biodetection using the microfluidic device has been carried out usingantigen sheep IgG and Alexafluor-647 tagged antibody particles and the experimentalresults prove that silicon is a compatible material for the present application given thevarious advantages it offers such as cost-effectiveness, ease of bulk microfabrication,superior surface affinity to biomolecules, ease of disposability of the device etc., and is thussuitable for fabricating Lab-on-a-chip type devices.
Wetland Restoration Response Analysis using MODIS and Groundwater Data
Authors: Melesse Assefa M. , Nangia Vijay , Wang Xixi , McClain Michael
Published: October 2008

Vegetation cover and groundwater level changes over the period of restorationare the two most important indicators of the level of success in wetland ecohydrologicalrestoration. As a result of the regular presence of water and dense vegetation, the highestevapotranspiration (latent heat) rates usually occur within wetlands. Vegetation cover andevapotranspiration of large areas of restoration like that of Kissimmee River basin, SouthFlorida will be best estimated using remote sensing technique than point measurements.Kissimmee River basin has been the area of ecological restoration for some years. Thecurrent ecohydrological restoration activities were evaluated through fractional vegetationcover (FVC) changes and latent heat flux using Moderate Resolution ImagingSpectroradiometer (MODIS) data. Groundwater level data were also analyzed for selectedeight groundwater monitoring wells in the basin. Results have shown that the averagefractional vegetation cover and latent heat along 10 km buffer of Kissimmee River betweenLake Kissimmee and Lake Okeechobee was higher in 2004 than in 2000. It is evident thatover the 5-year period of time, vegetated and areas covered with wetlands have increasedsignificantly especially along the restoration corridor. Analysis of groundwater level data(2000-2004) from eight monitoring wells showed that, the average monthly level ofgroundwater was increased by 20 cm and 34 cm between 2000 and 2004, and 2000 and2003, respectively. This change was more evident for wells along the river.
The Airborne Visible / Infrared Imaging Spectrometer AVIS: Design, Characterization and Calibration
Authors: Oppelt Natascha , Mauser Wolfram
Published: October 2008

The Airborne Visible / Infrared imaging Spectrometer AVIS is a hyperspectralimager designed for environmental monitoring purposes. The sensor, which wasconstructed entirely from commercially available components, has been successfullydeployed during several experiments between 1999 and 2007. We describe the instrumentdesign and present the results of laboratory characterization and calibration of the system’ssecond generation, AVIS-2, which is currently being operated. The processing of the datais described and examples of remote sensing reflectance data are presented.
Development of a Surface Plasmon Resonance n-dodecane Vapor Sensor
Authors: Aguirre Narcizo Muñoz , Pérez Lilia Martínez , Colín Jose Alfredo , Buenrostro-Gonzalez Eduardo
Published: October 2008

Using a high density polyethylene thin film over gold layer, a Surface PlasmonResonance sensor for detecting n-dodecane vapor is developed. Preliminary results will bepresented, showing that samples in the range of a few hundred ppm(V) of n-dodecanevapor in butane gas can be sensed. Also, studying the response as a function of time, it isdemonstrated that the sensing process is quickly reversible.
Global Distribution and Density of Constructed Impervious Surfaces
Authors: Elvidge Christopher D. , Tuttle Benjamin T. , Sutton Paul C. , Baugh Kimberly E. , Howard Ara T. , Milesi Cristina , Bhaduri Budhendra , Nemani Ramakrishna
Published: October 2008

We present the first global inventory of the spatial distribution and density ofconstructed impervious surface area (ISA). Examples of ISA include roads, parking lots,buildings, driveways, sidewalks and other manmade surfaces. While high spatialresolution is required to observe these features, the new product reports the estimateddensity of ISA on a one-km2 grid based on two coarse resolution indicators of ISA – thebrightness of satellite observed nighttime lights and population count. The model wascalibrated using 30-meter resolution ISA of the USA from the U.S. Geological Survey.Nominally the product is for the years 2000-01 since both the nighttime lights andreference data are from those two years. We found that 1.05% of the United States landarea is impervious surface (83,337 km2) and 0.43 % of the world’s land surface (579,703km2) is constructed impervious surface. China has more ISA than any other country(87,182 km2), but has only 67 m2 of ISA per person, compared to 297 m2 per person in theUSA. The distribution of ISA in the world’s primary drainage basins indicates that watersheds damaged by ISA are primarily concentrated in the USA, Europe, Japan, China and India. The authors believe the next step for improving the product is to include reference ISA data from many more areas around the world.
Models of Hydrogel Swelling with Applications to Hydration Sensing
Authors: Porter Timothy  L. , Stewart Ray , Reed Jim , Morton Kathryn
Published: October 2008

Hydrogels, polymers and various other composite materials may be used insensing applications in which the swelling or de-swelling of the material in response tosome analyte is converted via a transducer to a measurable signal. In this paper, we analyzemodels used to predict the swelling behavior of hydrogels that may be used in applicationsrelated to hydration monitoring in humans. Preliminary experimental data related toosmolality changes in fluids is presented to compare to the theoretical models. Overall,good experimental agreement with the models is achieved.
Integrated Love Wave Device Dedicated to Biomolecular Interactions Measurements in Aqueous Media
Authors: Blondeau-Patissier Virginie , Boireau Wilfrid , Cavallier Bruno , Lengaigne Gwladys , Daniau William , Martin Gilles , Ballandras Sylvain
Published: October 2008

Mass-sensitive electro-acoustic devices such as surface acoustic wave (SAW)micro-balances, capable to operate with aqueous media are particularly favorable for thedevelopment of biosensors. Their dimensions and physical properties offer a large potentialin biological fluid investigations, especially for measuring physical phenomenon (massdeposition, adsorption, pressure...). In this work, we propose a specific gratingconfiguration to lower the influence of viscosity of fluids which reduces the signal dynamicsof the surface wave transducers. A dedicated liquid cell also has been developed to isolatethe electro-active part of the device. The fabrication of the cell is achieved using theSU-8TMphoto-resist, allowing for manufacturing thick structures preventing any contact between thetested liquids and the transducers. Furthermore, the sensing area has been optimized tooptimize the sensor gravimetric sensitivity. The operation of the sensor is illustrated bydetecting bovine serum albumin (BSA) adsorption in the sensing area.
Development of Standardization and Management System for the Severity of Unpaved Test Courses
Authors: Kang Do-Kyung , Lee Sang-Ho , Goo Sang-Hwa
Published: October 2008

The vibration environment essentially accompanied by vehicle operation on theground is determined by the shape of road surface, which is called as profile. This paperfocuses on the development of profile measurement and severity analysis system forunpaved test courses. In general, the profile and severity of unpaved road is an importantissue in the reliability of endurance test. In order to measure and maintain unpaved roadprofile and severity, it is necessary to develop a profilometer system. The developedprofilometer system is composed of data processing computer, power unit, air compressorand sensors(encoder, vertical gyro and laser displacement). This study presents themeasuring system configuration, measurement principle of road profile and analysismethod of road characteristics used at CPG (Chang-won Proving Ground) for this purpose.In order to standardize and manage the severity of unpaved test courses, neural network isapplied
A Wetness Index Using Terrain-Corrected Surface Temperature and Normalized Difference Vegetation Index Derived from Standard MODIS Products: An Evaluation of Its Use in a Humid Forest-Dominated Region of Eastern Canada
Authors: Hassan Quazi K. , Bourque Charles P.-A. , Meng Fan-Rui , Cox Roger M.
Published: October 2008

In this paper we develop a method to estimate land-surface water content in amostly forest-dominated (humid) and topographically-varied region of eastern Canada. Theapproach is centered on a temperature-vegetation wetness index (TVWI) that uses standard 8-day MODIS-based image composites of land surface temperature (TS) and surface reflectanceas primary input. In an attempt to improve estimates of TVWI in high elevation areas, terrain-induced variations in TS are removed by applying grid, digital elevation model-basedcalculations of vertical atmospheric pressure to calculations of surface potential temperature(θS). Here, θS corrects TS to the temperature value to what it would be at mean sea level (i.e.,~101.3 kPa) in a neutral atmosphere. The vegetation component of the TVWI uses 8-daycomposites of surface reflectance in the calculation of normalized difference vegetation index(NDVI) values. TVWI and corresponding wet and dry edges are based on an interpretation ofscatterplots generated by plotting θS as a function of NDVI. A comparison of spatially-averaged field measurements of volumetric soil water content (VSWC) and TVWI for the 2003-2005 period revealed that variation with time to both was similar in magnitudes. Growing season, point mean measurements of VSWC and TVWI were 31.0% and 28.8% for 2003, 28.6% and 29.4% for 2004, and 40.0% and 38.4% for 2005, respectively. An evaluation of the long-term spatial distribution of land-surface wetness generated with the new θS-NDVI function and a process-based model of soil water content showed a strong relationship (i.e., r2 = 95.7%).
Investigation on Clarified Fruit Juice Composition by Using Visible Light Micro-Raman Spectroscopy
Authors: Camerlingo Carlo , Zenone Flora , Delfino Ines , Diano Nadia , Mita Damiano Gustavo , Lepore Maria
Published: October 2008

Liquid samples of clarified apple and apricot juices at different productionstages were investigated using visible light micro-Raman spectroscopy in order to assessits potential in monitoring fruit juice production. As is well-known, pectin plays a strategicrole in the production of clarified juice and the possibility of using Raman for its detectionduring production was therefore evaluated. The data analysis has enabled the clearidentification of pectin. In particular, Raman spectra of apple juice samples from washedand crushed fruits revealed a peak at 845 cm-1 (typical of pectin) which disappears in theRaman spectra of depectinised samples. The fructose content was also revealed by thepresence of four peaks at 823 cm-1, 872 cm-1, 918 cm-1 and 975 cm-1. In the case of apricotjuice, several Raman fingerprints of β-carotene at 1008, 1159 and 1520 cm-1 were alsohighlighted. Present results resulted interesting for the exclusive use of optical methods forthe quantitative determination of the above-mentioned substances in place of thebiochemical assays generally used for this purpose, which are time consuming and requiredifferent chemical reagents for each of them.
Quantitative Boundary Support Characterization for Cantilever MEMS
Authors: Rinaldi Gino , Packirisamy Muthukumaran , Stiharu Ion
Published: October 2008

Microfabrication limitations are of concern especially for suspended Micro-Electro-Mechanical-Systems (MEMS) microstructures such as cantilevers. The static anddynamic qualities of such microscale devices are directly related to the invariant and variantproperties of the microsystem. Among the invariant properties, microfabrication limitationscan be quantified only after the fabrication of the device through testing. However, MEMSare batch fabricated in large numbers where individual testing is neither possible nor costeffective. Hence, a suitable test algorithm needs to be developed where the test resultsobtained for a few devices can be applied to the whole fabrication batch, and also to thefoundry process in general. In this regard, this paper proposes a method to test MEMScantilevers under variant electro-thermal influences in order to quantify the effectiveboundary support condition obtained for a foundry process. A non-contact optical sensingapproach is employed for the dynamic testing. The Rayleigh-Ritz energy method usingboundary characteristic orthogonal polynomials is employed for the modeling andtheoretical analysis.
Determination of DPPH Radical Oxidation Caused by Methanolic Extracts of Some Microalgal Species by Linear Regression Analysis of Spectrophotometric Measurements
Authors: Marxen Kai , Vanselow Klaus Heinrich , Lippemeier Sebastian , Hintze Ralf , Ruser Andreas , Hansen Ulf-Peter
Published: October 2008

The demonstrated modified spectrophotometric method makes use of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and its specific absorbance properties. Theabsorbance decreases when the radical is reduced by antioxidants. In contrast to otherinvestigations, the absorbance was measured at a wavelength of 550 nm. This wavelengthenabled the measurements of the stable free DPPH radical without interference frommicroalgal pigments. This approach was applied to methanolic microalgae extracts for twodifferent DPPH concentrations. The changes in absorbance measured vs. the concentrationof the methanolic extract resulted in curves with a linear decrease ending in a saturationregion. Linear regression analysis of the linear part of DPPH reduction versus extractconcentration enabled the determination of the microalgae’s methanolic extractsantioxidative potentials which was independent to the employed DPPH concentrations. Theresulting slopes showed significant differences (6 - 34 μmol DPPH g-1 extractconcentration) between the single different species of microalgae (Anabaena sp.,Isochrysis galbana, Phaeodactylum tricornutum, Porphyridium purpureum, Synechocystissp. PCC6803) in their ability to reduce the DPPH radical. The independency of the signal on the DPPH concentration is a valuable advantage over the determination of the EC50 value.
Synthesis, Characterization and Metal Ion Detection of Novel Fluoroionophores Based on Heterocyclic Substituted Alanines
Authors: Costa Susana P. G. , Oliveira Elisabete , Lodeiro Carlos , Raposo M. Manuela M
Published: October 2008

The synthesis of new fluorescent probes containing the thiophene andbenzoxazole moieties combined with an alanine residue is described. The resulting highlyfluorescent heterocyclic alanine derivatives respond via a quenching effect, withparamagnetic Cu(II) and Ni(II) metal ions and with diamagnetic Hg(II), as shown by theabsorption and steady-state fluorescence spectroscopy studies. The formation ofmononuclear or dinuclear metal complexes was postulated based on the presence of thefree carboxylic acid as binding site and also with the interaction with the donor atoms inthe chromophore. Interaction with other important biological metal ions such as Zn(II),Ca(II) and Na(I) was also explored.
Modeling Forest Productivity Using Envisat MERIS Data
Authors: Berberoglu Suha , Evrendilek Fatih , Ozkan Coskun , Donmez Cenk
Published: October 2008

The aim of this study was to derive land cover products with a 300-m pixelresolution of Envisat MERIS (Medium Resolution Imaging Spectrometer) to quantify netprimary productivity (NPP) of conifer forests of Taurus Mountain range along the EasternMediterranean coast of Turkey. The Carnegie-Ames-Stanford approach (CASA) was usedto predict annual and monthly regional NPP as modified by temperature, precipitation,solar radiation, soil texture, fractional tree cover, land cover type, and normalizeddifference vegetation index (NDVI). Fractional tree cover was estimated using continuoustraining data and multi-temporal metrics of 47 Envisat MERIS images of March 2003 toSeptember 2005 and was derived by aggregating tree cover estimates made from high-resolution IKONOS imagery to coarser Landsat ETM imagery. A regression tree algorithmwas used to estimate response variables of fractional tree cover based on the multi-temporal metrics. This study showed that Envisat MERIS data yield a greater spatial detailin the quantification of NPP over a topographically complex terrain at the regional scalethan those used at the global scale such as AVHRR.
Improving Estimation Performance in Networked Control Systems Applying the Send-on-delta Transmission Method
Authors: Nguyen Vinh Hao , Suh Young Soo
Published: October 2008

This paper is concerned with improving performance of a state estimationproblem over a network in which a send-on-delta (SOD) transmission method is used. TheSOD method requires that a sensor node transmit data to the estimator node only if itsmeasurement value changes more than a given specified δ value. This method has beenexplored and applied by researchers because of its efficiency in the network bandwidthimprovement. However, when this method is used, it is not ensured that the estimator nodereceives data from the sensor nodes regularly at every estimation period. Therefore, wepropose a method to reduce estimation error in case of no sensor data reception. When theestimator node does not receive data from the sensor node, the sensor value is known to bein a (−δi , δi ) interval from the last transmitted sensor value. This implicit information hasbeen used to improve estimation performance in previous studies. The main contribution ofthis paper is to propose an algorithm, where the sensor value interval is reduced to(−δi / 2, δi / 2) in certain situations. Thus, the proposed algorithm improves the overallestimation performance without any changes in the send-on-delta algorithms of the sensornodes. Through numerical simulations, we demonstrate the feasibility and the usefulness ofthe proposed method.
Physical-Mechanical Properties of Nitrodopes Affected by Ultra-Violet Radiation
Authors: Cakić Suzana , Raskovic Ljiljana , Lačnjevac Časlav , Rajkovic Milos , Barać Miroljub , Stojanovic Miodrag
Published: October 2008

The FTIR spectroscopy has been employed in this research work to monitor theprocess of nitrodope photodegradation, by measuring surfaces of bands typical of a nitrogroup. Nitric esters are subject to degradation, which is reflected on a quantitative ratio ofthe surfaces of the IR bands that originate from the nitric ester. The obtained results showthat the length of the UV rays’ activity on the samples over the time periods of 240, 480and 960 minutes directly affects the spectrum appearance of the same sample before andafter the irradiation. The longer the action time of the UV rays and the higher a masspercentage of nitrocellulose in the nitrodope is, the smaller the bands’ surfaces become, i.e.the level of degradation is higher. In order to confirm the degradation of nitrodope, thedegree of crosslinking has also been examined by determining the König hardness and alsothe mean viscosity molar mass has been defined repeatedly applying the capillaryviscosimetry method.
Wireless Sensor/Actuator Network Design for Mobile Control Applications
Authors: Xia Feng , Tian Yu-Chu , Li Yanjun , Sung Youxian
Published: October 2008

Wireless sensor/actuator networks (WSANs) are emerging as a new generationof sensor networks. Serving as the backbone of control applications, WSANs will enablean unprecedented degree of distributed and mobile control. However, the unreliability ofwireless communications and the real-time requirements of control applications raise greatchallenges for WSAN design. With emphasis on the reliability issue, this paper presents anapplication-level design methodology for WSANs in mobile control applications. Thesolution is generic in that it is independent of the underlying platforms, environment,control system models, and controller design. To capture the link quality characteristics interms of packet loss rate, experiments are conducted on a real WSAN system. From theexperimental observations, a simple yet efficient method is proposed to deal withunpredictable packet loss on actuator nodes. Trace-based simulations give promisingresults, which demonstrate the effectiveness of the proposed approach.
Magnetostrictive Micro Mirrors for an Optical Switch Matrix
Authors: Lee Heung-Shik , Cho Chongdu , Cho Myeong-Woo
Published: October 2008

We have developed a wireless-controlled compact optical switch by siliconmicromachining techniques with DC magnetron sputtering. For the optical switchingoperation, micro mirror is designed as cantilever shape size of 5mm×800μm×50μm.TbDyFe film is sputter-deposited on the upper side of the mirror with the condition as: Argas pressure below 1.2×10-9 torr, DC input power of 180W and heating temperature of up to250°C for the wireless control of each component. Mirrors are actuated by externallyapplied magnetic fields for the micro application. Applied beam path can be changedaccording to the direction and the magnitude of applied magnetic field. Reflectivity changes,M-H curves and X-ray diffractions of sputtered mirrors are measured to determine magneto-optical, magneto-elastic properties with variation in sputtered film thickness. The deflectedangle-magnetic field characteristics of the fabricated mirror are measured.
High-rise Buildings versus Outdoor Thermal Environment in Chongqing
Authors: Lu Jun , Chen Jin-hua , Tang Ying , Wang Jin-sha
Published: October 2008

This paper gives a brief description of the over quick urbanization sinceChongqing, one of the biggest cities in China, has been a municipality directly under theCentral Government in 1997, excessive development and exceeding increase of high-risebuildings because of its special geographical position which finally leads to the worseningof the urban outdoor thermal environment. Then, this paper makes a bright balance to thefield measurement and simulated results of the wind speed field, temperature field of onemultifunctional high-rise building in Chongqing university located in the city center, andthe contrasted results validate the correctness of CFD in the outdoor thermal environmentalsimulation, expose the disadvantages of high-rise buildings on the aspects of blocking thewind field, decreasing wind speed which results in accumulation of the air-conditioningheat revolving around and periscian region where sunshine can not rip into. Finally, inorder to improve the urban outdoor thermal environment near the high-rise buildingsespecially for the angle of natural ventilation, this paper simulates the wind environment indifferent architectural compositions and architectural layouts by CFD, and the simulatedresults show that freestyle and tower buildings which can guarantee the wind speed andtake the air-conditioning heat away are much suitable and reasonable for the specialChongqing geography. These conclusions can also be used as a reference in othermountain cities, especially for the one with a great number of populations.
Multi-agent Negotiation Mechanisms for Statistical Target Classification in Wireless Multimedia Sensor Networks
Authors: Xue Wang , Bishop Dao-wei , Ding Liang , Wang Sheng
Published: October 2008

The recent availability of low cost and miniaturized hardware has allowedwireless sensor networks (WSNs) to retrieve audio and video data in real worldapplications, which has fostered the development of wireless multimedia sensor networks(WMSNs). Resource constraints and challenging multimedia data volume makedevelopment of efficient algorithms to perform in-network processing of multimediacontents imperative. This paper proposes solving problems in the domain of WMSNs fromthe perspective of multi-agent systems. The multi-agent framework enables flexible networkconfiguration and efficient collaborative in-network processing. The focus is placed ontarget classification in WMSNs where audio information is retrieved by microphones. Todeal with the uncertainties related to audio information retrieval, the statistical approachesof power spectral density estimates, principal component analysis and Gaussian processclassification are employed. A multi-agent negotiation mechanism is specially developed toefficiently utilize limited resources and simultaneously enhance classification accuracy andreliability. The negotiation is composed of two phases, where an auction based approach isfirst exploited to allocate the classification task among the agents and then individual agentdecisions are combined by the committee decision mechanism. Simulation experiments withreal world data are conducted and the results show that the proposed statistical approachesand negotiation mechanism not only reduce memory and computation requi
An Optical Biosensor based on Immobilization of Laccase and MBTH in Stacked Films for the Detection of Catechol.
Authors: Abdullah Jaafar , Ahmad Musa , Heng Lee Yook , Karuppiah Nadarajah , Sidek Hamidah
Published: October 2008

The fabrication of an optical biosensor by using stacked films where 3-methyl-2-benzothiazolinone hydrazone (MBTH) was immobilized in a hybrid nafion/sol-gelsilicate film and laccase in a chitosan film for the detection of phenolic compounds wasdescribed. Quinone and/or phenoxy radical product from the enzymatic oxidation ofphenolic compounds was allowed to couple with MBTH to form a colored azo-dye productfor spectrophometric detection. The biosensor demonstrated a linear response to catecholconcentration range of 0.5-8.0 mM with detection limit of 0.33 mM and response time of10 min. The reproducibility of the fabricated biosensor was good with RSD value of 5.3 %(n = 8) and stable for at least 2 months. The use of the hybrid materials of nafion/sol-gelsilicate to immobilize laccase has altered the selectivity of the enzyme to various phenoliccompounds such as catechol, guaicol, o-cresol and m-cresol when compared to the non-immobilized enzyme. When immobilized in this hybrid film, the biosensor response onlyto catechol and not other phenolic compounds investigated. Immobilization in this hybridmaterial has enable the biosensor to be more selective to catechol compared with the non-immobilized enzyme. This shows that by a careful selection of different immobilizationmatrices, the selectivity of an enzyme can be modified to yield a biosensor with goodselectivity towards certain targeted analytes.
A Urea Biosensor from Stacked Sol-Gel Films with Immobilized Nile Blue Chromoionophore and Urease Enzyme
Authors: Alqasaimeh Muawia Salameh , Heng Lee Yook , Ahmad Musa
Published: October 2008

An optical urea biosensor was fabricated by stacking several layers of sol-gelfilms. The stacking of the sol-gel films allowed the immobilization of a Nile Bluechromoionophore (ETH 5294) and urease enzyme separately without the need of anychemical attachment procedure. The absorbance response of the biosensor was monitoredat 550 nm, i.e. the deprotonation of the chromoionophore. This multi-layer sol-gel filmformat enabled higher enzyme loading in the biosensor to be achieved. The urea opticalbiosensor constructed from three layers of sol-gel films that contained urease demonstrateda much wider linear response range of up to 100 mM urea when compared with biosensorsthat constructed from 1-2 layers of films. Analysis of urea in urine samples with thisoptical urea biosensor yielded results similar to that determined by a spectrophotometricmethod using the reagent p-dimethylaminobenzaldehyde (R2 = 0.982, n = 6). The averagerecovery of urea from urine samples using this urea biosensor is approximately 103%.
Enhancement of BSA Binding on Au Surfaces by calix[4]bisazacrown Monolayer
Authors: Chen Hongxia , Kim Youn  Sook , Lee Jaebeom , Yoon Seok Ju , Lim Dong  Seob , Choi Heung-Jin , Koh Kwangnak
Published: October 2008

Effective investigation of biomolecular structure and function with chip-basedmodern instruments often requires reliable and steady attachment of designatedbiomolecules on substrate. Here, we investigated the formation of self-assembled monolayer(SAM) with a new calix[4]arene derivative containing bisazacrown ether at the lower rim(calix[4]bisazacrown) where ammonium moieties of proteins can mainly be interacted with.Immobilization process of protein using bovine serum albumin (BSA) on the Au surfacemodified with calix[4]bisazacrown monolyer as an artificial linker system was monitored bysurface plasmon resonance (SPR) technique. The surface concentration of BSA calculatedby the simulation of SPR experimental data was higher than that of a well-known similarcommercial protein linker. These results can help in modeling and understanding of proteinimmobilization on solid surface as well as further development lab-on-a-chip (LOC) devicesfor biomedical diagnosis kit of certain protein related diseases as biomarkers.