Search results for: small sample size
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4154

Search results for: small sample size

2114 Using Ultrasonic and Infrared Sensors for Distance Measurement

Authors: Tarek Mohammad

Abstract:

The amplitude response of infrared (IR) sensors depends on the reflectance properties of the target. Therefore, in order to use IR sensor for measuring distances accurately, prior knowledge of the surface must be known. This paper describes the Phong Illumination Model for determining the properties of a surface and subsequently calculating the distance to the surface. The angular position of the IR sensor is computed as normal to the surface for simplifying the calculation. Ultrasonic (US) sensor can provide the initial information on distance to obtain the parameters for this method. In addition, the experimental results obtained by using LabView are discussed. More care should be taken when placing the objects from the sensors during acquiring data since the small change in angle could show very different distance than the actual one. Since stereo camera vision systems do not perform well under some environmental conditions such as plain wall, glass surfaces, or poor lighting conditions, the IR and US sensors can be used additionally to improve the overall vision systems of mobile robots.

Keywords: Distance Measurement, Infrared sensor, Surface properties, Ultrasonic sensor.

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2113 Characterization and Modeling of Piezoelectric Integrated Micro Speakers for Audio Acoustic Actuation

Authors: J. Mendoza-López, S. Sánchez-Solano, J. L. Huertas-Díaz

Abstract:

An array of piezoelectric micro actuators can be used for radiation of an ultrasonic carrier signal modulated in amplitude with an acoustic signal, which yields audio frequency applications as the air acts as a self-demodulating medium. This application is known as the parametric array. We propose a parametric array with array elements based on existing piezoelectric micro ultrasonic transducer (pMUT) design techniques. In order to reach enough acoustic output power at a desired operating frequency, a proper ratio between number of array elements and array size needs to be used, with an array total area of the order of one cm square. The transducers presented are characterized via impedance, admittance, noise figure, transducer gain and frequency responses.

Keywords: Pizeoelectric, Microspeaker, MEMS, pMUT, Parametric Array

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2112 Concentrations and History of Heavy Metals in Sediment Cores: Geochemistry and Geochronology Using 210Pb

Authors: F. Fernandes, C. Poleto

Abstract:

This paper aims at assessing the concentrations of heavy metals and the isotopic composition of lead 210Pb in different fractions of sediment produced in the watershed that makes up the Mãe d'água dam and thus characterizing the distribution of metals along the sedimentary column and inferencing in the urbanization of the same process. Sample collection was carried out in June 2014; eight sediment cores were sampled in the lake of the dam. For extraction of the sediments core, a core sampler “Piston Core” was used. The trace metal concentrations were determined by conventional atomic absorption spectrophotometric methods. The samples were subjected to radiochemical analysis of 210Po. 210Pb activity was obtained by measuring 210Po activity. The chronology was calculated using the constant rate of supply (CRS). 210Pb is used to estimate the sedimentation rate.

Keywords: 210Pb dating method, heavy metal, lakes urban, pollution history.

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2111 Self-Assembling Hypernetworks for Cognitive Learning of Linguistic Memory

Authors: Byoung-Tak Zhang, Chan-Hoon Park

Abstract:

Hypernetworks are a generalized graph structure representing higher-order interactions between variables. We present a method for self-organizing hypernetworks to learn an associative memory of sentences and to recall the sentences from this memory. This learning method is inspired by the “mental chemistry" model of cognition and the “molecular self-assembly" technology in biochemistry. Simulation experiments are performed on a corpus of natural-language dialogues of approximately 300K sentences collected from TV drama captions. We report on the sentence completion performance as a function of the order of word-interaction and the size of the learning corpus, and discuss the plausibility of this architecture as a cognitive model of language learning and memory.

Keywords: Linguistic recall memory, sentence completion task, self-organizing hypernetworks, cognitive learning and memory.

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2110 Dynamic Analysis of Offshore 2-HUS/U Parallel Platform

Authors: Xie Kefeng, Zhang He

Abstract:

For the stability and control demand of offshore small floating platform, a 2-HUS/U parallel mechanism was presented as offshore platform. Inverse kinematics was obtained by institutional constraint equation, and the dynamic model of offshore 2-HUS/U parallel platform was derived based on rigid body’s Lagrangian method. The equivalent moment of inertia, damping and driving force/torque variation of offshore 2-HUS/U parallel platform were analyzed. A numerical example shows that, for parallel platform of given motion, system’s equivalent inertia changes 1.25 times maximally. During the movement of platform, they change dramatically with the system configuration and have coupling characteristics. The maximum equivalent drive torque is 800 N. At the same time, the curve of platform’s driving force/torque is smooth and has good sine features. The control system needs to be adjusted according to kinetic equation during stability and control and it provides a basis for the optimization of control system.

Keywords: 2-HUS/U platform, Dynamics, Lagrange, Parallel platform.

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2109 Thermal and Flammability Properties of Paraffin/Nanoclay Composite Phase Change Materials Incorporated in Building Materials for Thermal Energy Storage

Authors: Awni H. Alkhazaleh, Baljinder K. Kandola

Abstract:

In this study, a form-stable composite Paraffin/Nanoclay (PA-NC) has been prepared by absorbing PA into porous particles of NC to be used for low-temperature latent heat thermal energy storage. The leakage test shows that the maximum mass fraction of PA that can be incorporated in NC without leakage is 60 wt.%. Differential scanning calorimetry (DSC) has been used to measure the thermal properties of the PA and PA-NC both before and after incorporation in plasterboard (PL). The mechanical performance of the samples has been evaluated in flexural mode. The thermal energy storage performance has been studied using a small test chamber (100 mm × 100 mm × 100 mm) made from 10 mm thick PL and measuring the temperatures using thermocouples. The flammability of the PL+PL-NC has been discussed using a cone calorimeter. The results indicate that the form composite PA has good potential for use as thermal energy storage materials in building applications.

Keywords: Flammability, paraffin, plasterboard, thermal energy storage.

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2108 Differentiation of Heart Rate Time Series from Electroencephalogram and Noise

Authors: V. I. Thajudin Ahamed, P. Dhanasekaran, Paul Joseph K.

Abstract:

Analysis of heart rate variability (HRV) has become a popular non-invasive tool for assessing the activities of autonomic nervous system. Most of the methods were hired from techniques used for time series analysis. Currently used methods are time domain, frequency domain, geometrical and fractal methods. A new technique, which searches for pattern repeatability in a time series, is proposed for quantifying heart rate (HR) time series. These set of indices, which are termed as pattern repeatability measure and pattern repeatability ratio are able to distinguish HR data clearly from noise and electroencephalogram (EEG). The results of analysis using these measures give an insight into the fundamental difference between the composition of HR time series with respect to EEG and noise.

Keywords: Approximate entropy, heart rate variability, noise, pattern repeatability, and sample entropy.

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2107 The Relationship between Internal Corporate Social Responsibility and Organizational Commitment within the Banking Sector in Jordan

Authors: Al-bdour, A. Ali., Ellisha Nasruddin., Soh Keng Lin

Abstract:

This study attempts to investigate the relationship between internal CSR practices and organizational commitment based on the social exchange theory (SET). Specifically, we examine the impact of five dimensions of internal CSR practices on organizational commitment: health and safety, human rights, training and education, work life balance and workplace diversity. The proposed model was tested on a sample of 336 frontline employees within the banking sector in Jordan. Results showed that all internal CSR dimensions are significantly and positively related to affective and normative commitment. In addition, the findings of this study indicate that all internal CSR dimensions did not have a significant relationship with continuance commitment. Limitations of the study, directions for future research, and implications of the findings are discussed.

Keywords: Internal CSR, organizational commitment, Jordan, banking sector.

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2106 Nutrition Bio-Shield Superfood: Healthy and Live Herbal Supplement for Immune System Enhancement

Authors: Azam Bayat, Aref Khalkhali, Ali Reza Mahjoub

Abstract:

Healthy and viable herbal supplement were prepared from wheat by a green route. This organic biomaterial was named Nutrition Bio-shield Superfood (NBS). The NBS supplement had various vitamins, macro and micro molecules, and ingredients. In this study, 20 small Balb/C labile specimens were used in a weighing 30 ± 5 range. The samples were randomly divided into different groups, then the groups were divided into 5 groups. According to the results of this study, the mean number of white blood cells and neutrophil percentage in the experimental group receiving healthy and live dietary supplement showed a significant increase at the 5% probability level in all three groups received 50, 100 and 150 mg/ kg body weight of the mouse compared to the control group. In general, the dietary supplement increases the level of immunity.

Keywords: Healthy and live herbal supplement, biomaterial, immune system, enhancement.

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2105 Application of BP Neural Network Model in Sports Aerobics Performance Evaluation

Authors: Shuhe Shao

Abstract:

This article provides partial evaluation index and its standard of sports aerobics, including the following 12 indexes: health vitality, coordination, flexibility, accuracy, pace, endurance, elasticity, self-confidence, form, control, uniformity and musicality. The three-layer BP artificial neural network model including input layer, hidden layer and output layer is established. The result shows that the model can well reflect the non-linear relationship between the performance of 12 indexes and the overall performance. The predicted value of each sample is very close to the true value, with a relative error fluctuating around of 5%, and the network training is successful. It shows that BP network has high prediction accuracy and good generalization capacity if being applied in sports aerobics performance evaluation after effective training.

Keywords: BP neural network, sports aerobics, performance, evaluation.

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2104 Preservation of Carbon Dioxide Clathrate Hydrate Coexisting with Sucrose at Temperatures below the Water Freezing Point under Atmospheric Pressure

Authors: Tadaaki Sato, Ryo Ohmura

Abstract:

This paper reports the influence of sucrose on the preservation of CO2 hydrate crystal samples. The particle diameter of hydrate samples were 1.0 and 5.6-8.0 mm. Mass fraction of sucrose in the sample was 0.16. The samples were stored at the aerated condition under atmospheric pressure and at the temperature of 253 or 258 K. The results indicated that the mass fractions of CO2 hydrate in the samples with sucrose were 0.10 ± 0.03 at the end of 3-week preservation, regardless of temperature and particle diameter. Mass fraction of CO2 hydrate in the samples with sucrose was higher than that of pure CO2 hydrate for 1.0 mm particle diameter, while was lower than that of pure CO2 hydrate for 5.6-8.0 mm particle diameter. Discussion is made on the influence of sucrose on the dissociation of CO2 hydrate and the resulting formation of ice.

Keywords: Clathrate hydrates, Carbon dioxide

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2103 Assessing and Visualizing the Stability of Feature Selectors: A Case Study with Spectral Data

Authors: R.Guzman-Martinez, Oscar Garcia-Olalla, R.Alaiz-Rodriguez

Abstract:

Feature selection plays an important role in applications with high dimensional data. The assessment of the stability of feature selection/ranking algorithms becomes an important issue when the dataset is small and the aim is to gain insight into the underlying process by analyzing the most relevant features. In this work, we propose a graphical approach that enables to analyze the similarity between feature ranking techniques as well as their individual stability. Moreover, it works with whatever stability metric (Canberra distance, Spearman's rank correlation coefficient, Kuncheva's stability index,...). We illustrate this visualization technique evaluating the stability of several feature selection techniques on a spectral binary dataset. Experimental results with a neural-based classifier show that stability and ranking quality may not be linked together and both issues have to be studied jointly in order to offer answers to the domain experts.

Keywords: Feature Selection Stability, Spectral data, Data visualization

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2102 Improving Cache Memory Utilization

Authors: Sami I. Serhan, Hamed M. Abdel-Haq

Abstract:

In this paper, an efficient technique is proposed to manage the cache memory. The proposed technique introduces some modifications on the well-known set associative mapping technique. This modification requires a little alteration in the structure of the cache memory and on the way by which it can be referenced. The proposed alteration leads to increase the set size virtually and consequently to improve the performance and the utilization of the cache memory. The current mapping techniques have accomplished good results. In fact, there are still different cases in which cache memory lines are left empty and not used, whereas two or more processes overwrite the lines of each other, instead of using those empty lines. The proposed algorithm aims at finding an efficient way to deal with such problem.

Keywords: Modified Set Associative Mapping, Locality of Reference, Miss Ratio, Hit Ratio, Cache Memory, Clustered Behavior, Index Address, Tag Field, Status Field, and Complement of Index Address.

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2101 Performance and Emission Study of Linseed Oilas a Fuel for CI Engine

Authors: Ashutosh Kumar Rai, Naveen Kumar, Bhupendra Singh Chauhan

Abstract:

Increased energy demand and the concern about environment friendly technology, renewable bio-fuels are better alternative to petroleum products. In the present study linseed oil was used as alternative source for diesel engine fuel and the results were compared with baseline data of neat diesel. Performance parameters such as brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) and emissions parameters such as CO, unburned hydro carbon (UBHC), NOx, CO2 and exhaust temperature were compared. BTE of the engine was lower and BSFC was higher when the engine was fueled with Linseed oil compared to diesel fuel. Emission characteristics are better than diesel fuel. NOx formation by using linseed oil during the experiment was lower than diesel fuel. Linseed oil is non edible oil, so it can be used as an extender of diesel fuel energy source for small and medium energy needs.

Keywords: Bio-fuel, exhaust emission, linseed oil, triglyceride.

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2100 Comparison of an Interior Mounted Permanent Magnet Synchronous Generator with a Synchronous Reluctance Generator for a Wind Application

Authors: Poopak Roshanfekr, Torbjörn Thiringer, Sonja Lundmark, Mikael Alatalo

Abstract:

This article presents a performance comparison of an interior mounted permanent magnet synchronous generator (IPMSG) with a synchronous reluctance generator (SynRG) with the same size for a wind application. It is found that using the same geometrical dimensions, a SynRG can convert 74 % of the power that an IPMSG can convert, while it has 80% of the IPMSG weight. Moreover it is found that the efficieny for the IMPSG is 99% at rated power compared to 98.7% for the SynRG.

Keywords: Interior mounted permanent magnet synchronous generator (IPMSG), synchronous reluctance generator (SynRG), wind energy, annual energy efficiency.

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2099 All Proteins Have a Basic Molecular Formula

Authors: Homa Torabizadeh

Abstract:

This study proposes a basic molecular formula for all proteins. A total of 10,739 proteins belonging to 9 different protein groups classified on the basis of their functions were selected randomly. They included enzymes, storage proteins, hormones, signalling proteins, structural proteins, transport proteins, immunoglobulins or antibodies, motor proteins and receptor proteins. After obtaining the protein molecular formula using the ProtParam tool, the H/C, N/C, O/C, and S/C ratios were determined for each randomly selected sample. In this case, H, N, O, and S coefficients were specified per carbon atom. Surprisingly, the results demonstrated that H, N, O, and S coefficients for all 10,739 proteins are similar and highly correlated. This study demonstrates that despite differences in the structure and function, all known proteins have a similar basic molecular formula CnH1.58 ± 0.015nN0.28 ± 0.005nO0.30 ± 0.007nS0.01 ± 0.002n. The total correlation between all coefficients was found to be 0.9999.

Keywords: Protein molecular formula, Basic unit formula, Protparam tool.

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2098 Organizational Socialization Levels in Nurses

Authors: M. Aslan, A. Karaaslan, S. Selcuk

Abstract:

The research was conducted in order to determine the organizational socialization levels of nurses working in hospitals in the form of a descriptive study. The research population was composed of nurses employed in public and private sector hospitals in the province of Konya with 0-3 years of professional experience in the hospitals (N=1200); and the sample was composed of 495 nurses that accepted to take part in the study voluntarily. Statistical evaluation of data was conducted in SPSS.16 software. The results of the study revealed that the total score taken by nurses at the organizational socialization scale was 262.95; and this was close to the maximum score. Particularly the departmental socialization sub-dimension proved to be higher in comparison to the other two dimensions (organization socialization and task socialization). Statistically meaningful differences were found in the levels of organization socialization in relation to the status of organizational orientation training, level of education and age group.

Keywords: Nurses, Newcomers, Organizational Socialization.

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2097 The Determination of Heavy Metal in Herb Used in Dusit Community to Develop a Sustainable Quality of Life

Authors: Chinnawat Satsananan

Abstract:

This research aimed to find amount of heavy metal in herb used in Dusit community and compare of heavy metal in each part by quantity in herb and standard determination in Thai herb books to develop a sustainable quality of life, the result of study in 14 herbs do not find sample of heavy metal., by quantity of heavy contamination of 4 kinds: Cd, Co, Fe and Pb have lower than standard of 2 organizations: Thai herb standard, and World Health Organization, from the test 14 herbs have Fe in every part of herbs and all 14 kinds has Fe that is necessary for our health.

Keywords: Herbs Plants, Heavy Metal, Dusit District

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2096 Modeling Electric Field Distribution on Insulator under Electron Bombardment in Vacuum

Authors: A.G.E. Sutjipto, Jufriadi, R. Muhida, Afzeri, E.Y. Adesta

Abstract:

Charging and discharging phenomenon on the surface of materials can be found in plasma display panel, spacecraft charging, high voltage insulator, etc. This report gives a simple explanation on this phenomenon. A scanning electron microscope was used not only as a tool to produce energetic electron beam to charge an insulator without metallic coating and to produce a surface discharging (surface breakdown/flashover) but also to observe the visible charging and discharging on the sample surface. A model of electric field distribution on the surface was developed in order to explain charging and discharging phenomena. Since charging and discharging process involves incubation time, therefore this process can be used to evaluate the insulation property of materials under electron bombardment.

Keywords: Flashover, SEM, Electron Bombardment, Electric Field.

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2095 A Research on Inference from Multiple Distance Variables in Hedonic Regression – Focus on Three Variables

Authors: Yan Wang, Yasushi Asami, Yukio Sadahiro

Abstract:

In urban context, urban nodes such as amenity or hazard will certainly affect house price, while classic hedonic analysis will employ distance variables measured from each urban nodes. However, effects from distances to facilities on house prices generally do not represent the true price of the property. Distance variables measured on the same surface are suffering a problem called multicollinearity, which is usually presented as magnitude variance and mean value in regression, errors caused by instability. In this paper, we provided a theoretical framework to identify and gather the data with less bias, and also provided specific sampling method on locating the sample region to avoid the spatial multicollinerity problem in three distance variable’s case.

Keywords: Hedonic regression, urban node, distance variables, multicollinerity, collinearity.

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2094 Innovation Strategy in Slovak Businesses

Authors: V. Lendel, M. Varmus

Abstract:

The aim of the paper is based on detailed analysis of literary sources and carried out research to develop a model development and implementation of innovation strategy in the business. The paper brings the main results of the authors conducted research on a sample of 462 respondents that shows the current situation in the Slovak enterprises in the use of innovation strategy. Carried out research and analysis provided the base for a model development and implementation of innovation strategy in the business, which is in the paper in detail, step by step explained with emphasis on the implementation process. Implementing the innovation strategy is described a separate model. Paper contains recommendations for successful implementation of innovation strategy in the business. These recommendations should serve mainly business managers as valuable tool in implementing the innovation strategy.

Keywords: innovation, innovation strategy, innovative management, innovative potential

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2093 A Novel Nano-Scaled SRAM Cell

Authors: Arash Azizi Mazreah, Mohammad Reza Sahebi, Mohammad T. Manzuri Shalmani

Abstract:

To help overcome limits to the density of conventional SRAMs and leakage current of SRAM cell in nanoscaled CMOS technology, we have developed a four-transistor SRAM cell. The newly developed CMOS four-transistor SRAM cell uses one word-line and one bit-line during read/write operation. This cell retains its data with leakage current and positive feedback without refresh cycle. The new cell size is 19% smaller than a conventional six-transistor cell using same design rules. Also the leakage current of new cell is 60% smaller than a conventional sixtransistor SRAM cell. Simulation result in 65nm CMOS technology shows new cell has correct operation during read/write operation and idle mode.

Keywords: SRAM Cell, leakage current, cell area.

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2092 Measuring the Level of Housing Defects in the Build-Then-Sell Housing Delivery System

Authors: S. N. F. Mohd Fauzi, N. Yusof, N. Zainul Abidin

Abstract:

When the Malaysian government announced the implementation of the Build-Then-Sell (BTS) system in 2007, the proponents of the BTS have argued that the implementation of this new system may provide houses with low defects. However, there has been no empirical data to support their argument. Therefore, this study is conducted to measure the level of housing defects in the BTS housing delivery system. A survey was conducted to the occupiers in six BTS residential areas. The BTS residential areas have been identified through the media and because of the small number of population, all households in the BTS residential areas were required to participate in the study to enable the researcher to collect the data concerning defects. Questionnaire had been employed as the data collection instrument and was distributed to the respondents of this study. The result has shown that the level of defects in the BTS houses is low, as the rate of defects for all elements are slight. Such low level of defects has apparently only affected the aesthetic value of the houses.

Keywords: Build-Then-Sell houses, housing defects, residentialareas, occupiers

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2091 Two DEA Based Ant Algorithms for CMS Problems

Authors: Hossein Ali Akbarpour, Fatemeh Dadkhah

Abstract:

This paper considers a multi criteria cell formation problem in Cellular Manufacturing System (CMS). Minimizing the number of voids and exceptional elements in cells simultaneously are two proposed objective functions. This problem is an Np-hard problem according to the literature, and therefore, we can-t find the optimal solution by an exact method. In this paper we developed two ant algorithms, Ant Colony Optimization (ACO) and Max-Min Ant System (MMAS), based on Data Envelopment Analysis (DEA). Both of them try to find the efficient solutions based on efficiency concept in DEA. Each artificial ant is considered as a Decision Making Unit (DMU). For each DMU we considered two inputs, the values of objective functions, and one output, the value of one for all of them. In order to evaluate performance of proposed methods we provided an experimental design with some empirical problem in three different sizes, small, medium and large. We defined three different criteria that show which algorithm has the best performance.

Keywords: Ant algorithm, Cellular manufacturing system, Data envelopment analysis, Efficiency

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2090 The Design, Development, and Optimization of a Capacitive Pressure Sensor Utilizing an Existing 9 DOF Platform

Authors: Andrew Randles, Ilker Ocak, Cheam Daw Don, Navab Singh, Alex Gu

Abstract:

Nine Degrees of Freedom (9 DOF) systems are already in development in many areas. In this paper, an integrated pressure sensor is proposed that will make use of an already existing monolithic 9 DOF inertial MEMS platform. Capacitive pressure sensors can suffer from limited sensitivity for a given size of membrane. This novel pressure sensor design increases the sensitivity by over 5 times compared to a traditional array of square diaphragms while still fitting within a 2 mm x 2 mm chip and maintaining a fixed static capacitance. The improved design uses one large diaphragm supported by pillars with fixed electrodes placed above the areas of maximum deflection. The design optimization increases the sensitivity from 0.22 fF/kPa to 1.16 fF/kPa. Temperature sensitivity was also examined through simulation.

Keywords: Capacitive pressure sensor, 9 DOF, 10 DOF, sensor, capacitive, inertial measurement unit, IMU, inertial navigation system, INS.

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2089 Three-Dimensional Numerical Simulation of Drops Suspended in Poiseuille Flow: Effect of Reynolds Number

Authors: A. Nourbakhsh

Abstract:

A finite difference/front tracking method is used to study the motion of three-dimensional deformable drops suspended in plane Poiseuille flow at non-zero Reynolds numbers. A parallel version of the code was used to study the behavior of suspension on a reasonable grid resolution (grids). The viscosity and density of drops are assumed to be equal to that of the suspending medium. The effect of the Reynolds number is studied in detail. It is found that drops with small deformation behave like rigid particles and migrate to an equilibrium position about half way between the wall and the centerline (the Segre-Silberberg effect). However, for highly deformable drops there is a tendency for drops to migrate to the middle of the channel, and the maximum concentration occurs at the centerline. The effective viscosity of suspension and the fluctuation energy of the flow across the channel increases with the Reynolds number of the flow.

Keywords: Suspensions, Poiseuille flow, Effective viscosity, Reynolds number.

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2088 Considering Aerosol Processes in Nuclear Transport Package Containment Safety Cases

Authors: Andrew Cummings, Rhianne Boag, Sarah Bryson, Gordon Turner

Abstract:

Packages designed for transport of radioactive material must satisfy rigorous safety regulations specified by the International Atomic Energy Agency (IAEA). Higher Activity Waste (HAW) transport packages have to maintain containment of their contents during normal and accident conditions of transport (NCT and ACT). To ensure containment criteria is satisfied these packages are required to be leak-tight in all transport conditions to meet allowable activity release rates. Package design safety reports are the safety cases that provide the claims, evidence and arguments to demonstrate that packages meet the regulations and once approved by the competent authority (in the UK this is the Office for Nuclear Regulation) a licence to transport radioactive material is issued for the package(s). The standard approach to demonstrating containment in the RWM transport safety case is set out in BS EN ISO 12807. In this document a method for measuring a leak rate from the package is explained by way of a small interspace test volume situated between two O-ring seals on the underside of the package lid. The interspace volume is pressurised and a pressure drop measured. A small interspace test volume makes the method more sensitive enabling the measurement of smaller leak rates. By ascertaining the activity of the contents, identifying a releasable fraction of material and by treating that fraction of material as a gas, allowable leak rates for NCT and ACT are calculated. The adherence to basic safety principles in ISO12807 is very pessimistic and current practice in the demonstration of transport safety, which is accepted by the UK regulator. It is UK government policy that management of HAW will be through geological disposal. It is proposed that the intermediate level waste be transported to the geological disposal facility (GDF) in large cuboid packages. This poses a challenge for containment demonstration because such packages will have long seals and therefore large interspace test volumes. There is also uncertainty on the releasable fraction of material within the package ullage space. This is because the waste may be in many different forms which makes it difficult to define the fraction of material released by the waste package. Additionally because of the large interspace test volume, measuring the calculated leak rates may not be achievable. For this reason a justification for a lower releasable fraction of material is sought. This paper considers the use of aerosol processes to reduce the releasable fraction for both NCT and ACT. It reviews the basic coagulation and removal processes and applies the dynamic aerosol balance equation. The proposed solution includes only the most well understood physical processes namely; Brownian coagulation and gravitational settling. Other processes have been eliminated either on the basis that they would serve to reduce the release to the environment further (pessimistically in keeping with the essence of nuclear transport safety cases) or that they are not credible in the conditions of transport considered.

Keywords: Aerosol processes, Brownian coagulation, gravitational settling, transport regulations.

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2087 A Methodology for Quality Problems Diagnosis in SMEs

Authors: Humberto N. Teixeira, Isabel S. Lopes, Sérgio D. Sousa

Abstract:

This article proposes a new methodology to be used by SMEs (Small and Medium enterprises) to characterize their performance in quality, highlighting weaknesses and area for improvement. The methodology aims to identify the principal causes of quality problems and help to prioritize improvement initiatives. This is a self-assessment methodology that intends to be easy to implement by companies with low maturity level in quality. The methodology is organized in six different steps which includes gathering information about predetermined processes and subprocesses of quality management, defined based on the well-known Juran-s trilogy for quality management (Quality planning, quality control and quality improvement) and, predetermined results categories, defined based on quality concept. A set of tools for data collecting and analysis, such as interviews, flowcharts, process analysis diagrams and Failure Mode and effects Analysis (FMEA) are used. The article also presents the conclusions obtained in the application of the methodology in two cases studies.

Keywords: Continuous improvement, Diagnosis, Quality Management, Self-assessment, SMEs

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2086 Watermark Bit Rate in Diverse Signal Domains

Authors: Nedeljko Cvejic, Tapio Sepp

Abstract:

A study of the obtainable watermark data rate for information hiding algorithms is presented in this paper. As the perceptual entropy for wideband monophonic audio signals is in the range of four to five bits per sample, a significant amount of additional information can be inserted into signal without causing any perceptual distortion. Experimental results showed that transform domain watermark embedding outperforms considerably watermark embedding in time domain and that signal decompositions with a high gain of transform coding, like the wavelet transform, are the most suitable for high data rate information hiding. Keywords?Digital watermarking, information hiding, audio watermarking, watermark data rate.

Keywords: Digital watermarking, information hiding, audio watermarking, watermark data rate.

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2085 Durability Aspects of Recycled Aggregate Concrete: An Experimental Study

Authors: Smitha Yadav, Snehal Pathak

Abstract:

Aggregate compositions in the construction and demolition (C&D) waste have potential to replace normal aggregates. However, to re-utilise these aggregates, the concrete produced with these recycled aggregates needs to provide the desired compressive strength and durability. This paper examines the performance of recycled aggregate concrete made up of 60% recycled aggregates of 20 mm size in terms of durability tests namely rapid chloride permeability, drying shrinkage, water permeability, modulus of elasticity and creep without compromising the compressive strength. The experimental outcome indicates that recycled aggregate concrete provides strength and durability same as controlled concrete when processed for removal of adhered mortar.

Keywords: Compressive strength, recycled aggregate, shrinkage, rapid chloride permeation test, modulus of elasticity, water permeability.

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