bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerodynamic Behaviour of a Novel Three-Dimensional Shaped Transonic Compressor Rotor Blade
Authors: Biollo Roberto , Benini Ernesto
Published: August 2009

This paper compares the aerodynamic behaviour of baseline and redesigned versions of the well-known NASA Rotor 37. The aerodynamic behaviour of the two rotors was evaluated using an accurate and validated 3-D CFD RANS model. The redesigned version showed both higher efficiency and wider stall margin. The new rotor was modeled by giving to the radial stacking line of baseline blade a three-dimensional shape. The blade was curved mainly toward the direction of rotor rotation. The applied blade curvature comes from previous personal investigations on the effects of stacking line shape in transonic bladings. Steady-state simulations were carried out to calculate the flow field inside the two rotors. The numerical model was developed using a commercial CFD code. The code was validated by simulating the Rotor 37 and comparing the computed results to the experimental data available in the open literature. The validation process gave a satisfactory agreement between predictions and measurements, showing that the overall features of the three-dimensional shock structure, shock-boundary layer interaction and tip clearance flows are calculated well in the numerical solution. With respect to the baseline rotor, the redesigned version gave a higher efficiency in a large part of the operating range, with a maximum increment of about 1.2 percentage points around the peak efficiency condition. The improvements in efficiency can be associated with a less detrimental shock-blade boundary layer interaction at the outer span, probably due to the different three-dimensional shock structure developed. At the outer span, in fact, the new blade showed a blade-to-blade shock front more oblique than in the baseline rotor. Further, the new blade positively impacted the flow field near the casing at low flow operating conditions. A less detrimental shock-tip clearance vortex-boundary layer interaction, along with a considerable reduction of the low momentum fluid region after the shock, was observed. CFD flow visualizations showed clearly a higher stall margin. The last stable operating point provided by the numerical model implemented gave a normalized mass flow of about 92% in the case of Rotor 37 (in accordance with experimental data) and about 90% in the case of redesigned version. The two rotors showed a similar choking mass flow rate.
Verification of Low NOx Performance of Simple Primary Rich Combustion Approach by a Newly Established Full Annular Combustor Test Facility
Authors: Makida Mitsumasa , Yamada Hideshi , Shimodaira Kazuo , Yoshida Seiji , Kurosawa Yoji , Yamamoto Takeshi
Published: August 2009

In the TechCLEAN project of JAXA, experimental research has been being conducted to develop a combustor for a small aircraft engine (with pressure ratio of about 20). The combustor was tuned to show the behavior of the Rich-Lean combustion through tests under atmospheric and practical conditions. And in 2006, by a designed multi-sector combustor, NOx emissions were reduced to lower than 42% of the ICAO CAEP4 standard. Based on the tuned combustor, full annular combustors were designed. In parallel, an experimental facility to test the full annular combustors under practical conditions was newly constructed in the spring of 2007. The inlet air conditions were set to the ICAO LTO cycle conditions of the target engine; 0.3–1.8MPa for pressure, 400–700K for temperature and 4–18kg/s for air mass flow rate. Through the full annular combustion experiments under practical conditions, the combustors were tuned to keep good combustion performance which was verified by the multi-sector combustors. The optimized full annular combustor finally achieved the following performance; NOx emissions were reduced to lower than 40% of the ICAO CAEP4 standard, maintaining low CO and THC emissions, good exit temperature profiles (P.T.F. = 0.19 at the take-off condition) and good lean blow-out performance (AFR>200 at the idle condition). The process of the optimization is discussed in this report.
On Damping Entire Bladed Disks Through Dampers on Only a Few Blades
Authors: Avalos Javier , Mignolet Marc P.
Published: August 2009

The focus of this paper is on demonstrating the potential to damp entire bladed disks using dampers on only a fraction of the blades. This problem is first considered without the presence of random mistuning and it is demonstrated that a few dampers at optimized locations can lead to a significant reduction in the forced response of the entire bladed disk. Unfortunately, this optimum design may not be robust with respect to random mistuning and a notable fraction of the reduction in forced response obtained may disappear because of mistuning. To regain the reduction in forced response but with mistuning present, robustness to mistuning is enhanced by using intentional mistuning in addition to dampers. The intentional mistuning strategy selected here is the A/B pattern mistuning in which the blades all belong to either type A or B. An optimization effort is then performed to obtain the best combination of A/B pattern and damper location to minimize the mistuned forced response of the disk. The addition of intentional mistuning in the system is shown to be very efficient and the optimum bladed disk design does indeed exhibit a significant reduction of mistuned forced response as compared to the tuned system. These findings were obtained on both single-degree-of-freedom per blade disk models and a reduced order model of a blisk.
Gas Turbine Integrated High-Efficiency Oxy-Fuel Combustion Process With CO2 Capture
Authors: Zanganeh Kourosh E. , Shafeen Ahmed , Gupta Murlidhar , Ogendengbe Emmanuel O. B. , Mitrovic Milenka
Published: August 2009

Fossil fuel energy conversion processes are the primary source of anthropogenic greenhouse gas emissions. New approach to utilization of fossil fuels through near-zero emission energy conversion systems represents an emerging opportunity for developing new concepts and designs, increasing the efficiency of the baseline combustion processes and reducing their environmental footprints, including greenhouse gas emissions, through CO2 capture and storage. Oxy-fuel combustion process provides an elegant way to address the environmental issues, in particular CO2 emissions, associated with current combustion systems. In this process nearly pure oxygen (instead of air) is burned with fuel. The resulting flue gas is composed mainly of CO2 and H2O, and other trace contaminants (e.g., SOx, NOx and particulates). The challenge faced in the development of oxy-fuel systems is the inability of current design configurations and materials for combustors, boilers, and turbo-machinery, to operate at the high temperatures resulting from burning the fuel in pure oxygen. Recent development at CANMET has been focused on design of a new generation of advanced oxy-fuel systems. These systems are very compact and can be integrated with a modified gas turbine to generate electricity, while the products of combustion can be sent to another turbine for recovery. The resulting CO2-rich stream at the outlet of the turbine is then sent to a CO2 capture and compression unit to separate and compress CO2 for pipeline transport. In this paper we present this proposed gas turbine integrated high-efficiency oxy-fuel combustion process and its main components, including the gas turbine and heat recovery system design. Moreover, we will present the results of the overall system integration, performance modeling and simulation to develop the tools required to asses the efficiency and viability of the overall integrated system and its components.
Redesign of a Low Speed Turbine Stage Using a New Viscous Inverse Design Method
Authors: Roidl Benedikt , Ghaly Wahid
Published: August 2009

The midspan section of a low speed subsonic turbine stage that is built and tested at DFVLR, Cologne, is redesigned using a new inverse blade design method where the blade walls move with a virtual velocity distribution derived from the difference between the current and the target pressure distributions on the blade surfaces. This new inverse method is fully consistent with the viscous flow assumption and is implemented into the time accurate solution of the Reynolds-Averaged Navier-Stokes equations. An algebraic Baldwin-Lomax turbulence model is used for turbulence closure. The mixing plane approach is used to couple the stator and the rotor regions. The CFD analysis formulation is first assessed against the turbine stage experimental data. The inverse formulation that is implemented in the same CFD code is also assessed for its robustness and merits. The inverse design method is then used to study the effect of the rotor pressure loading on the blade shape and stage performance. It is also used to simultaneously redesign both stator and rotor blades for improved stage performance. The results show that by carefully tailoring the target pressure loading on both blade rows, improvement can be achieved in the stage performance.
Parametric Thermodynamic Analysis of a Solid Oxide Fuel Cell Gas Turbine System Design Space
Authors: Tarroja Brian , Mueller Fabian , Maclay Jim , Brouwer Jacob
Published: August 2009

A parametric study of Solid Oxide Fuel Cell – Gas Turbine (SOFC-GT) hybrid system design is conducted with the intention of determining the thermodynamically-based design space constrained by modern material and operating limits. The analysis is performed using a thermodynamic model of a generalized SOFC-GT system where the sizing of all components, except the fuel cell, is allowed to vary. Effects of parameters such as pressure ratio, fuel utilization, oxygen utilization, and current density are examined. Operational limits are discussed in terms of maximum combustor exit temperature, maximum heat exchanger effectiveness, limiting current density, maximum hydrogen utilization, and fuel cell temperature rise. It was found that the maximum hydrogen utilization and combustor exit temperature were the most significant constraints on the system design space. The design space includes the use of cathode flow recycle and air preheat via a recuperator (heat exchanger). The effect on system efficiency of exhaust gas recirculation using an ejector versus the use of a blower is discussed, while both are compared to the base case of using a heat exchanger only. It was found that use of an ejector for exhaust gas recirculation caused the highest efficiency loss, and the base case was found to exhibit the highest overall system efficiency. The use of a cathode recycle blower allowed the largest downsizing of the heat exchanger, although avoiding cathode recycling achieved the highest efficiency. Efficiencies in the range of 50 – 75% were found for variations in pressure ratio, fuel utilization, oxygen utilization, and current density. The best performing systems that fell within all design constraints were those that used a heat exchanger only to preheat air, moderate pressure ratios, low oxygen utilizations and high fuel utilizations.
A Novel Strategy for Passive Control of Combustion Instabilities Through Modification of Flame Dynamics
Authors: Noiray Nicolas , Durox Daniel , Schuller Thierry , Candel Se´bastien
Published: August 2009

Passive control of combustion instabilities is explored in the case of systems featuring a collection of premixed flames. The method devised in this research differs from the general strategies employed to passively hinder the growth of acoustic-combustion oscillations by augmenting acoustic damping. Dissipation of acoustic energy is usually obtained by connecting Helmholtz resonators or quarter wave type cavities or by placing perforated plate linings around the system. While these systems effectively reduce pressure oscillations, optimum performance is not always obtained over the full range of operating conditions and their implementation requires substantial space which is not often available in practice. Conceptually, these standard techniques deal with the consequences of combustion instabilities but not with the driving sources. It is shown here that an alternative solution may be to directly act on the causes of the onset of thermo-acoustic coupling. The basic idea is to modify the flames dynamics using the dynamical response of the injection system. The principle of the passive control strategy proposed on this basis is to counteract the onset of oscillations by tackling the underlying causes. The injection system is modified to avoid a coherent motion of the flames when they are submitted to an acoustic modulation and reduce the coupling between acoustic perturbations and heat release fluctuations. Numerical simulations and experimental data are presented and one may infer that the method could bring a substantial improvement to the system stability. The efficiency of this technique is demonstrated in the case of small premixed flames anchored on a multipoint injection system (the configuration is that of a premixed gaseous-fueled multipoint dump combustor), but the principle is more general and can be extended to larger scale turbulent combustors featuring a collection of flames.
Aerodynamics of Compressor Casing Treatment: Part II—A Quasi-Steady Model for Casing Treatment Flows
Authors: Ning Fangfei , Xu Liping
Published: August 2009

In order to predict more efficiently the flow in compressor with casing treatment in a integrated manner as well as to facilitate an integrated tool for the design optimization of casing treatment, a mathematical-physical quasi-steady model for the slot-type casing treatment flows were developed based on the understanding of the unsteady flow physics of the rotor-casing treatment combination. The new model has been coded up and validated against a slot-type casing treatment which is examined by experiment and unsteady RANS calculations in the companion paper Part I. The calculations using this model show an encouraging agreement with those obtained from measurements and unsteady RANS calculations, indicating the essence of the flow physics has been captured by the model. Although the model is based on the slot type casing treatment, the principle behind it is rather wide-catching and extensions to other types of casing/hub treatment can also be realized. Since the model equations for the casing treatment flow are solved in the same way as that for conventional steady flows, considerable amount of computer resources can be saved. This enables the model applicable in the current steady RANS-based design system, and overall assessments of a compressor with an applied casing treatment are readily achievable.
A new experimental setup for high-pressure catalytic activity measurements on surface deposited mass-selected Pt clusters
Authors: Watanabe Yoshihide , Isomura Noritake
Published: July 2009

A new experimental setup to study catalytic and electronic properties of size-selected clusters on metal oxide substrates from the viewpoint of cluster-support interaction and to formulate a method for the development of heterogeneous catalysts such as automotive exhaust catalysts has been developed. The apparatus consists of a size-selected cluster source, a photoemission spectrometer, a scanning tunneling microscope (STM), and a high-pressure reaction cell. The high-pressure reaction cell measurements provided information on catalytic properties in conditions close to practical use. The authors investigated size-selected platinum clusters deposited on a TiO2(110) surface using a reaction cell and STM. Catalytic activity measurements showed that the catalytic activities have a cluster-size dependency.
Changes in Abundance of Two Percids,Perca fluviatilisandGymnocephalus cernuus, along a Productivity Gradient: Relations to Feeding Strategies and Competitive Abilities
Authors: Bergman Eva
Published: August 2009

Relative abundances of perch (Perca fluviatilis) and ruffe (Gymnocephalus cernuus) were studied in eight lakes ranked along a gradient of increasing productivity. The diets of perch and ruffe in relation to food resources were quantified over a 5-mo period in one lake of moderate and one lake of high productivity. The abundance of perch decreased and that of ruffe increased along the productivity gradient. Large perch ate fish over the whole season in the more productive lake, but rarely ate fish in May and June in the less productive lake. All size classes of ruffe fed mainly on macrobenthos in both lakes. The diversity of macrobenthos was higher in the lake of low productivity, as was the diet breadth of ruffe. The abundance patterns of perch and ruffe are likely related to the simultaneous effect of increasing prey abundance and decreasing light penetration with increasing productivity. Furthermore, the abundance of perch is likely affected by increasing interspecific competition and that of ruffe by decreasing predation pressure as productivity increases.
Effects of Ageing Errors on Recruitment Time Series Estimated from Sequential Population Analysis
Authors: Bradford Michael J.
Published: August 2009

Ageing errors can introduce considerable bias in the time series of recruitment estimated from a sequential population analysis. Simulation results indicate that mild ageing errors can halve estimates of the variance of recruitment and can introduce potentially important autocorrelations in recruitment time series. Underageing resulting from the use of unvalidated ageing techniques can affect recruitment estimates sufficiently to severely hinder studies of environmental influences on recruitment. As an additional sensitivity analysis, researchers should consider recalculating recruitment after correcting catch data for ageing errors.
Distinguishing between resident and migrating Atlantic salmon (Salmo salar) stocks by genetic stock composition analysis
Authors: Koljonen Marja-Liisa
Published: August 2009

The possibility of using the genetic stock identification (GSI) method to distinguish between individual Atlantic salmon (Salmo salar) stocks and stock groups in Finnish catches was studied. In the Baltic Sea, the Atlantic salmon is a target of a mixed-stock fishery, and information about stock composition would be valuable for the management of the species. The salmon catches on the Finnish west coast consist of two seasonally variable components: a group of northern stocks migrating through the area to the Baltic main basin and the resident Neva salmon. The migratory component includes two endangered wild stocks (Tornionjoki and Simojoki). The allele frequency differences at four polymorphic loci among the stocks allowed reliable catch composition estimates to be made of the migratory and resident components; one stock (Oulujoki) from the northern group could also be identified with reasonable accuracy. Northern migrating stocks accounted for over half the catches at the time of this study. The estimate of natural (nonhatchery) stocks was very low (3% in total).
Diel vertical migration: A possible host-finding mechanism in salmon louse (Lepeophtheirus salmonis) copepodids?
Authors: Heuch Peter Andreas , Parsons Aengus , Boxaspen Karin
Published: August 2009

The vertical distribution of pelagic nauplii and copepodids of the salmon louse Lepeophtheirus salmonis Krøyer was studied in large enclosures in the sea. Copepodids, which infect salmonid hosts, displayed a distinct diel vertical migration pattern. They gathered near the surface during the day, and spread out into deeper layers at night. Nauplii showed only small differences in depth between night and day. Copepodid distribution seems to be controlled by light intensity; no effect of either salinity or temperature was found. This migration pattern, which is the reverse of that of wild salmonids, may increase the number of parasite–host encounters as hosts will swim through populations of sinking (nighttime) and rising (dawn) parasites every 24 h. Because caged salmon feed at the surface during the day, they are likely to be more exposed to infective copepodids than wild fish.
Biological and physical variables associated with aggregations of the giant scallop Placopecten magellanicus
Authors: Stokesbury Kevin D. E. , Himmelman John H.
Published: August 2009

To identify factors that may determine where aggregations (beds) of giant scallops (Placopecten magellanicus) develop, we compared physical and biological conditions in two scallop beds in Port Daniel Bay, Baie des Chaleurs, Gulf of St. Lawrence, with conditions in seven adjacent areas. Gravel substratum predominantly characterized scallop beds. Physical hydrographic conditions and the intensity of asteroid predation were similar within scallop beds and in surrounding areas with few scallops. High P. magellanicus spat settlement density was not consistently correlated with existing scallop aggregations, but filamentous organisms, on which scallops preferentially settle, were more abundant in scallop beds, possibly enhancing recruitment. Scallop growth rate varied among areas and was intermediate within scallop beds. Winter flounder (Pseudopleuronectes americanus) and Atlantic wolffish (Anarhichas lupus) preyed on P. magellanicus and may influence scallop distribution. Scallop tethering experiments indicated that risk of predation was low within scallop beds compared with adjacent areas. Scallop mortality was positively correlated with mean density of both rock crab (Cancer irroratus) and American lobster (Homarus americanus). We conclude that gravel substratum, low decapod predation, and presence of filamentous flora and fauna are critical factors determining scallop aggregation location.
On the use of structured time-series to detect and test hypotheses about within-lakes relationships
Authors: Prairie Yves T. , Marshall C. Tara
Published: August 2009

Aquatic scientists using empirical relationships developed from point measurements or averages from different lakes often assume that these relationships also apply to individual lakes over time. However, this assumption is difficult to test because the extent of variation within a single system is generally much smaller and the relationship accordingly less defined than across a number of systems. We present a new method to extract empirical relationships from the internal structure of a time-series within a single lake. When we applied the method to an extreme simulation, we were able to recover accurately the parameters of the relationship in spite of the absence of any apparent relationship between the variables. When applied to empirical data for phosphorus and chlorophyll concentrations collected daily over one field season, the estimated structural relationship was nearly identical to that estimated from cross-sectional data even though the empirical trend appeared much shallower and very weak.
Regulatory properties of yeast nitrate reductase in situ
Authors: Choudary V. Prabhakara , Rao G. Ramananda
Published: August 2009

A simple and rapid procedure to make yeast cells permeable by agitating with toluene–ethanol, (TE) 1:4, v/v was developed. The permeated cells retained their ability to catalyze certain enzyme reactions. Temperature and duration of agitation during TE treatment played an important role in retention of the catalytic potential of permeated cells. The in situ assay using permeated cell preparations was more sensitive even in the absence of added cofactors than the in vitro assay in detecting assimilatory nitrate reductase (NAD(P)H:nitrate oxidoreductase, EC 1.6.6.2) (NAR) activity in Candida utilis.Using in situ assay technique, different mechanisms regulating the biosynthesis of NAR in C. utilis were investigated. Nitrogen starvation did not lead to derepression of NAR. NO3− ions were absolutely essential for induction and maintenance of high levels of NAR activity. Cells grown on ammonium nitrate possessed relatively lower levels of NAR. Kinetics of NAR induction were followed as a function of time and inducer concentration. The influence of various cations on the induction of NAR by nitrate was investigated. A wide range of D-amino acids induced NAR synthesis. Of 22 L-amino acids tested only phenylalanine induced significant levels of NAR. Various intermediates of the pathway of nitrate reduction influenced the rate of NAR induction. There was a rapid disappearance of in vivo activity of the enzyme of induced yeast cells on nitrogen starvation, and the rate of loss was accelerated by the presence of NH4+.
USING ANT COLONY OPTIMIZATION TO MINIMIZE THE FUZZY MAKESPAN AND TOTAL WEIGHTED FUZZY COMPLETION TIME IN FLOW SHOP SCHEDULING PROBLEMS
Authors: LAI PENG-JEN , WU HSIEN-CHUNG
Published: July 2009

The flow shop scheduling problems with fuzzy processing times are investigated in this paper. For some special kinds of fuzzy numbers, the analytic formulas of the fuzzy compltion time can be obtained. For the general bell-shaped fuzzy numbers, we present a computational procedure to obtain the approximated membership function of the fuzzy completion time. We define a defuzzification function to rank the fuzzy numbers. Under this ranking concept among fuzzy numbers, we plan to minimize the fuzzy makespan and total weighted fuzzy completion time. Because the ant colony algorithm has been successfully used to solve the scheduling problems with real-valued processing times, we shall also apply the ant colony algorithm to search for the best schedules when the processing times are assumed as fuzzy numbers. Numerical examples are also provided and solved by using the commercial software MATLAB.
A NONLINEAR PROGRAMMING APPROACH TO MATRIX GAMES WITH PAYOFFS OF ATANASSOV'S INTUITIONISTIC FUZZY SETS
Authors: LI DENG-FENG , NAN JIANG-XIA
Published: July 2009

The intuitionistic fuzzy set (IFS) introduced by Atanassov in 1986 is characterized by two functions and has rarely been applied to the game theory yet. The aim of this paper is to develop the concept and methodology of matrix games with payoffs of Atanassov's IFSs. In this methodology, the concepts of the solutions for matrix games with payoffs of Atanassov's IFSs are defined based on the degree of membership and the degree of non-membership. It is proven that matrix games with payoffs of Atanassov's IFSs have solutions, which can be obtained through solving a pair of nonlinear programming models derived from two auxiliary nonlinear bi-objective programming models. The proposed method is illustrated with a numerical example.
BARGAINING POWER IN THE NASH DEMAND GAME AN EVOLUTIONARY APPROACH
Authors: SANTAMARIA-GARCIA JUANA
Published: July 2009

A population of buyers and a population of sellers meet repeatedly in order to exchange a good. The price is fixed through a variant of the Nash demand game. This paper analyzes the prices that are robust to experimentation in the sense of stochastic stability. Under some conditions only one price is selected and it gives a share of the surplus to each side of the market that corresponds to the generalized Nash bargaining solution. The bargaining power of each party depends on the division of the unclaimed surplus and the population sizes. The bargaining power of a given population will increase either with a reduction in its fraction of the unclaimed surplus or with a decrease in its own size.
A FACE RECOGNITION SCHEME BASED ON EMBEDDED HIDDEN MARKOV MODEL AND SELECTIVE ENSEMBLE STRATEGY
Authors: GAO XINBO , LI JINXIU , XIAO BING
Published: August 2009

As an effective method, the embedded hidden Markov model (E-HMM) has been widely used in pattern recognition. On applying the E-HMM to face recognition, the performance heavily depends on the selection of model parameters. Aiming at the problem of model selection, a selective ensemble of multi E-HMMs based face recognition algorithm is proposed. Experimental results illustrate that compared with the traditional E-HMM based face recognition algorithm the proposed method cannot only obtain better and more stable recognition performance, but also achieve higher generalization ability.
IMAGE WATERMARKING BASED ON THE HESSENBERG TRANSFORM
Authors: SEDDIK HASSEN , SAYADI MOUNIR , FNAIECH FARHAT , CHERIET MOHAMED
Published: August 2009

Watermarking is now considered as an efficient means for assuring copyright protection and data owner identification. Watermark embedding techniques depend on the representation domain of the image (spatial, frequency, and multiresolution). Every domain has its specific advantages and limitations. Moreover, each technique in a chosen domain is found to be robust to specific sets of attack types. So we need to propose more robust domains to defeat these limitations and respect all the watermarking criterions (capacity, invisibility and robustness). In this paper, a new watermarking method is presented using a new domain for the image representation and the watermark embedding: the mathematical Hessenberg transformation. This domain is found to be robust against a wide range of STIRMARK attacks such as JPEG compression, convolution filtering and noise adding. The robustness of the new technique in preserving and extracting the embedded watermark is proved after various attacks types. It is also improved when compared with other methods in use. In addition, the proposed method is blind and the use of the host image is not needed in the watermark detection process.
DENSE ESTIMATION OF OPTICAL FLOW FIELD WITHIN THE MPEG-2 COMPRESSED DOMAIN
Authors: YANG GAOBO , CHEN WEIWEI , WANG XIAO JING , ZHANG ZHAOYANG
Published: August 2009

A dense estimation of optical flow field within the MPEG-2 compressed domain is proposed, which utilizes only the compressed-domain information, i.e. motion vectors and DCT coefficients. First, motion vectors are pre-processed to estimate the DCT coefficients for P and B frames. Second, initial optical flow is estimated with Black's optical flow estimation framework, in which DC image is substituted by DC+2AC image to provide more intensity information. Third, high confidence test is exploited to generate the dense and accurate motion vector field by removing false and noisy motion vectors. It preserves the advantages of compressed domain processing and improves the existent MPEG velocity field in terms of accuracy and density. Experimental results demonstrate that the proposed approach can provide a satisfactory motion analysis for compressed-domain video object extraction.
A MODEL OF ATTITUDES TOWARDS THE ACCEPTANCE OF MOBILE PHONE USE IN PUBLIC PLACES
Authors: MAK BRENDA , NICKERSON ROBERT C. , ISAAC HENRI
Published: August 2009

Since the first commercial launch of cellular telecoms by NET in Tokyo Japan in 1979 and the launch of the NMT system in Denmark, Finland, Norway and Sweden in 1981, the mobile phone has undergone continual incremental innovation for changing market needs. This study investigates the factors affecting the attitudes towards the social acceptance of mobile phones in public places and how this attitude affects its usage. Theories on innovation and technology acceptance were reviewed, and studies relating demographic factors to technology acceptance were examined. A model was proposed relating the usage frequency and attitudes towards acceptance of mobile phone in public places to demographic factors, such as country, age, education, gender, and work status. A survey was conducted among mobile phone users, and the sample consisted of 1079 respondents in the United States, France, Italy, Turkey, and Finland. A structural equation model was developed to analyze the survey data. Results of the analysis indicate that the attitudes about mobile phone use in public places depend on country, and age factors. This attitude in turn significantly affects the usage frequency of mobile phones. In addition, usage frequency also is affected by gender and work status. Implications of the findings for both academicians and practitioners are discussed.
TECHNOLOGY TRANSFER FOR PRODUCT LIFE CYCLE EXTENSION: A MODEL FOR SUCCESSFUL IMPLEMENTATION
Authors: CORMICAN KATHRYN , O'CONNOR MICHAEL
Published: August 2009

This paper examines the logistical and operational issues relating to technology transfer. It documents the specific problems encountered as well as the solution designed to overcome these problems. The paper presents a model for technology transfer that incorporates a sequence of stages or steps that should be considered when planning, scheduling and executing a transfer from one location to another. The model ensures that roles are clarified, appropriate training is undertaken, validation processes are considered, supply to the market is maintained and all relevant information and equipment is transferred in a controlled, timely and cost effective manner.
OBJECTS SEGMENTATION USING MULTIPLE FEATURES FOR ROBOT NAVIGATION ON OUTDOOR ENVIRONMENT
Authors: KIM DAE-NYEON , TRINH HOANG-HON , JO KANG-HYUN
Published: August 2009

This paper presents the method to recognize objects for autonomous robot navigation in outdoor environment. The proposition of the method segments from an image taken by a moving robot in an outdoor environment. The method begins with object segmentation, which uses multiple features to obtain the object of segmented region. Multiple features are color, context information, line segments, edge, Hue Co-occurrence Matrix (HCM), Principal Components (PCs) and Vanishing Points (VPs). We model the objects of outdoor environment that define their characteristics individually. We segment the region as a mixture using the proposed features and methods. Objects can be detected when we combine predefined multiple features. Next, the stage classifies the object into natural and artificial ones. We detect sky and trees of natural objects. And we detect building of artificial objects. The last stage shows the combination of appearance and context information. We implement the result of object segmentation using multiple features through experiments.
STRUCTURAL RESPONSES OF A NOVEL HIGH FLEXION KNEE (SS316–UHMWPE) USED IN TOTAL KNEE ARTHROPLASTY USING FINITE ELEMENT ANALYSIS
Authors: SIVARASU SUDESH , MATHEW LAZAR
Published: August 2009

The application of finite element modeling in medical applications has been evolving as the field of high importance especially in the development of medical. The generic artificial knee implants used in the total knee arthroplasty have the restriction in its range of motion with around 90 degrees. A new design allowing flexion extension range of over 120 degrees has been designed with a view to facilitate partial squatting and the same is used for the analysis purpose. The loading conditions of 10 times the body weight are considered. Finite element analyses of this design have been carried out based on standard biomaterial used in orthopaedic implants. In this paper we discuss the results of analyses of an artificial knee with stainless steel alloy. The results of the analyses were used in identifying areas of extreme stresses within the design and the spot prone for higher deformation. Based on these results slight modification on the designs was carried out. The results are also verified whether the body is within the linear deformation levels. As the results obtained were very satisfactory the models have been recommended for prototyping.

It is verified from the results that the new models respond positive till a load of 300 kg and then they enter into the maximum yield stress levels. However, in reality, the loading on an artificial knee is less than 300 kg. So the results are inferred positive and the models were sent for prototyping.
Is active sweating during heat acclimation required for improvements in peripheral sweat gland function?
Authors: Buono Michael J. , Numan Travis R. , Claros Ryan M. , Brodine Stephanie K. , Kolkhorst Fred W.
Published: August 2009

We investigated whether the eccrine sweat glands must actively produce sweat during heat acclimation if they are to adapt and increase their capacity to sweat. Eight volunteers received intradermal injections of BOTOX, to prevent neural stimulation and sweat production of the sweat glands during heat acclimation, and saline injections as a control in the contralateral forearm. Subjects performed 90 min of moderate-intensity exercise in the heat (35°C, 40% relative humidity) on 10 consecutive days. Heat acclimation decreased end-exercise heart rate (156 ± 22 vs. 138 ± 17 beats/min; P = 0.0001) and rectal temperature (38.2 ± 0.3 vs. 37.9 ± 0.3°C; P = 0.0003) and increased whole body sweat rate (0.70 ± 0.29 vs. 1.06 ± 0.50 l/h; P = 0.030). During heat acclimation, there was no measurable sweating in the BOTOX-treated forearm, but the control forearm sweat rate during exercise increased 40% over the 10 days ( P = 0.040). Peripheral sweat gland function was assessed using pilocarpine iontophoresis before and after heat acclimation. Before heat acclimation, the pilocarpine-induced sweat rate of the control and BOTOX-injected forearms did not differ (0.65 ± 0.20 vs. 0.66 ± 0.22 mg·cm−2·min−1). However, following heat acclimation, the pilocarpine-induced sweat rate in the control arm increased 18% to 0.77 ± 0.21 mg·cm−2·min−1 ( P = 0.021) but decreased 52% to 0.32 ± 0.18 mg·cm−2·min−1 ( P < 0.001) in the BOTOX-treated arm. Using complete chemodenervation of the sweat glands, coupled with direct cholinergic stimulation via pilocarpine iontophoresis, we demonstrated that sweat glands must be active during heat acclimation if they are to adapt and increase their capacity to sweat.
Muscle apoptosis is induced in pressure-induced deep tissue injury
Authors: Siu Parco M. , Tam Eric W. , Teng Bee T. , Pei Xiao M. , Ng Joann W. , Benzie Iris F. , Mak Arthur F.
Published: July 2009

Pressure ulcer is a complex and significant health problem. Although the factors including pressure, shear, and ischemia have been identified in the etiology of pressure ulcer, the cellular and molecular mechanisms that contribute to the development of pressure ulcer are unclear. This study tested the hypothesis that the early-onset molecular regulation of pressure ulcer involves apoptosis in muscle tissue. Adult Sprague-Dawley rats were subjected to an in vivo protocol to mimic pressure-induced deep tissue injury. Static pressure was applied to the tibialis region of the right limb of the rats for 6 h each day on two consecutive days. The compression force was continuously monitored by a three-axial force transducer equipped in the compression indentor. The contralateral uncompressed limb served as intra-animal control. Tissues underneath the compressed region were collected for histological analysis, terminal dUTP nick-end labeling (TUNEL), cell death ELISA, immunocytochemical staining, and real-time RT-PCR gene expression analysis. The compressed muscle tissue generally demonstrated degenerative characteristics. TUNEL/dystrophin labeling showed a significant increase in the apoptotic muscle-related nuclei, and cell death ELISA demonstrated a threefold elevation of apoptotic DNA fragmentation in the compressed muscle tissue relative to control. Positive immunoreactivities of cleaved caspase-3, Bax, and Bcl-2 were evident in compressed muscle. The mRNA contents of Bax, caspase-3, caspase-8, and caspase-9 were found to be higher in the compressed muscle tissue than control. These results demonstrated that apoptosis is activated in muscle tissue following prolonged moderate compression. The data are consistent with the hypothesis that muscle apoptosis is involved in the underlying mechanism of pressure-induced deep tissue injury.
AC Conductivity and Impedance Properties of 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3Ceramics
Authors: Behera Banarji , Araújo E. B. , Reis R. N. , Guerra J. D. S.
Published: August 2009

The electrical properties of 0.65Pb(Mg1/3Nb2/3)O3-0.35(PbTiO3) ceramics over a wide range of frequencies (102–106 Hz) and temperatures (30–225∘C) were studied using impedance spectroscopy technique. The impedance and electric permittivity were strongly temperature and frequency dependent. The activation energy, calculated from the temperature dependence of AC conductivity of the ceramics was found to be∼0.5 eV. The relaxation process in the ceramics was found to be of non-Debye type. The nature of Cole-Cole diagram reveals the contribution of grain (bulk) and grain boundary permittivity in the ceramics.
Polymer Light‐Emitting Diodes Efficiency Dependence on Bipolar Charge Traps Concentration
Authors: Morgado Luis , Alcácer Luis , Morgado Jorge
Published: August 2009

The efficiency of light‐emitting diodes (LEDs) based on poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐alt‐1,4‐benzo‐{2,1′‐3}‐thiadiazole)],
F8BT, is optimized upon simultaneous doping with a hole and an electron trapping molecule, namely,
N,N′‐Bis(3‐methylphenyl)‐N,N′‐diphenylbenzidine and 2‐(4‐biphenylyl)‐5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole,
respectively. It is shown that, for devices with poly(3,4‐ethylene dioxythiophene) doped with polystyrene
sulfonic acid as hole‐injection layer material and magnesium cathodes, the efficiency is nearly doubled
(from ca. 2.5 to 3.7 cd/A) upon doping with ca. 0.34% by weight of both compounds.
Process Monitoring with Multivariate p-Control Chart
Authors: Cozzucoli Paolo C.
Published: August 2009

We assume that the operator is interested in monitoring a multinomial process. In this case the items are classified into (k+1) ordered distinct and mutually exclusive defect categories. The first category is used to classify the conforming defect-free items, while the remaining k categories are used to classify the nonconforming items in k defect grades, with increasing degrees of nonconformity. Usually the process is said to be capable if the overall proportion of nonconforming items is very small and remains low, or declines over time. Nevertheless, since we classify the nonconforming items into k distinct defect grades, the operator can also evaluate the overall level of defectiveness. This quality parameter depends on the k defect categories. Furthermore, we are interested in evaluating, over time, the proportion of nonconforming items in each category as well as the overall level of defectiveness. To achieve this goal, we propose (i) a normalized index that can be used to evaluate the capability of the process in terms of the overall level of defectiveness, and (ii) a two-sided Shewhart-type multivariate control chart to monitor the overall proportion of nonconforming items and the corresponding defectiveness level.
Deciphering the Impact of Common Genetic Variation on Lung Cancer Risk: A Genome-Wide Association Study
Authors: Broderick Peter , Wang Yufei , Vijayakrishnan Jayaram , Matakidou Athena , Spitz Margaret R. , Eisen Timothy , Amos Christopher I. , Houlston Richard S.
Published: August 2009

To explore the impact of common variation on the risk of developing lung cancer, we conducted a two-phase genome-wide association (GWA) study. In phase 1, we compared the genotypes of 511,919 tagging single nucleotide polymorphisms (SNP) in 1,952 cases and 1,438 controls; in phase 2, 30,568 SNPs were genotyped in 2,465 cases and 3,005 controls. SNP selection was based on best supported P values from phase 1 and two other GWA studies of lung cancer. In the combined analysis of phases 1 and 2, the strongest associations identified were defined by SNPs mapping to 15q25.1 (rs12914385; P = 3.19 × 10−16), 5p15.33 (rs4975616; P = 6.66 × 10−7), and 6p21.33 (rs3117582; P = 9.13 × 10−7). Variation at 15q25.1, but not 5p15.33 or 6p21.33, was strongly associated with smoking behavior with risk alleles correlated to higher consumption. Variation at 5p15.33 was shown to significantly influence induction of lung cancer histology. Pooling data from the four series provided 21,620 genotypes for 7,560 cases and 8,205 controls. A meta-analysis provided increased support that variation at 15q25.1 (rs8034191; P = 3.24 × 10−26), 5p15.33 (rs4975616; P = 2.99 × 10−9), and 6p21.33 (rs3117582; P = 4.46 × 10−10) influences lung cancer risk. The next best-supported associations were attained at 15q15.2 (rs748404: P = 1.08 × 10−6) and 10q23.31 (rs1926203; P = 1.28 × 10−6). These data indicate few common variants account for 1% of the excess familial risk underscoring the necessity of having additional large sample series for gene discovery. [Cancer Res 2009;69(16):6633–41]
Ulcer Size as a Novel Indicator Marker Is Correlated with Prognosis of Ulcerative Gastric Cancer
Authors: Xu C.Y. , Shen J.G. , Shen J.Y. , Chen W.J. , Wang L.B.
Published: August 2009

Aims: The objective of this study was to assess the significance of ulcer size for the survival of gastric cancer patients. Methods: A total of 260 patients with ulcerative gastric cancer who had undergone curative resection were reviewed. The diameter of the malignant ulcer was measured. Patients were divided into group U1 (≤3 cm) and group U2 (>3 cm) according to the diameter of the ulcer. The prognostic significance of ulcer size was assessed by uni- and multivariate analyses. Results: Patient survival was correlated with age, gender, tumor location, tumor size, ulcer size, serosal invasion, node involvement and synchronism distant metastasis. The 5-year overall survival rate in U1 patients was 84.3% as compared with 67.5% in U2 patients (p < 0.001), and the 5-year recurrence-free survival rates were 82.9% for group U1 and 62.5% for group U2 (p = 0.001). Multivariate analysis revealed that ulcer size is an independently significant predictive factor for survival rates (overall: hazard ratio 1.222, p = 0.003; recurrence-free: hazard ratio 1.205, p = 0.006). Conclusion: Ulcer size might be a potential indicator for advanced disease and the use of minimal local treatments must be considered carefully in larger ulcer size patients.
Midlife Serum Cholesterol and Increased Risk of Alzheimer’s and Vascular Dementia Three Decades Later
Authors: Solomon Alina , Kivipelto Miia , Wolozin Benjamin , Zhou Jufen , Whitmer Rachel A.
Published: August 2009

Aims: To investigate midlife cholesterol in relation to Alzheimer’s disease (AD) and vascular dementia (VaD) in a large multiethnic cohort of women and men. Methods: The Kaiser Permanente Northern California Medical Group (healthcare delivery organization) formed the database for this study. The 9,844 participants underwent detailed health evaluations during 1964–1973 at ages 40–45 years; they were still members of the health plan in 1994. AD and VaD were ascertained by medical records between 1 January 1994 and 1 June 2007. Cox proportional hazards models – adjusted for age, education, race/ethnic group, sex, midlife diabetes, hypertension, BMI and late-life stroke – were conducted. Results: In total, 469 participants had AD and 127 had VaD. With desirable cholesterol levels (<200 mg/dl) as a reference, hazard ratios (HR) and 95% CI for AD were 1.23 (0.97–1.55) and 1.57 (1.23–2.01) for borderline (200–239 mg/dl) and high cholesterol (≥240 mg/dl), respectively. HR and 95% CI for VaD were 1.50 (1.01–2.23) for borderline and 1.26 (0.82–1.96) for high cholesterol. Further analyses for AD (cholesterol quartiles, 1st quartile reference) indicated that cholesterol levels >220 mg/dl were a significant risk factor: HR were 1.31 (1.01–1.71; 3rd quartile, 221–248 mg/dl) and 1.58 (1.22–2.06; 4th quartile, 249–500 mg/dl). Conclusion: Midlife serum total cholesterol was associated with an increased risk of AD and VaD. Even moderately elevated cholesterol increased dementia risk. Dementia risk factors need to be addressed as early as midlife, before underlying disease(s) or symptoms appear.