Search results for: Receiver-operating characteristic curve
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2398

Search results for: Receiver-operating characteristic curve

1108 Dielectric Spectroscopy Investigation of Hydrophobic Silica Aerogel

Authors: Deniz Bozoglu, Deniz Deger, Kemal Ulutas, Sahin Yakut

Abstract:

In recent years, silica aerogels have attracted great attention due to their outstanding properties, and their wide variety of potential applications such as microelectronics, nuclear and high-energy physics, optics and acoustics, superconductivity, space-physics. Hydrophobic silica aerogels were successfully synthesized in one-step by surface modification at ambient pressure. FT-IR result confirmed that Si-OH groups were successfully converted into hydrophobic and non-polar Si-CH3 groups by surface modification using trimethylchloro silane (TMCS) as co-precursor. Using Alpha-A High-Resolution Dielectric, Conductivity and Impedance Analyzer, AC conductivity of samples were examined at temperature range 293-423 K and measured over frequency range between 1-106 Hz. The characteristic relaxation time decreases with increasing temperature. The AC conductivity follows σ_AC (ω)=σ_t-σ_DC=Aω^s relation at frequencies higher than 10 Hz, and the dominant conduction mechanism is found to obey the Correlated Barrier Hopping (CBH) mechanism. At frequencies lower than 10 Hz, the electrical conduction is found to be in accordance with DC conduction mechanism. The activation energies obtained from AC conductivity results and it was observed two relaxation regions.

Keywords: aerogel, synthesis, dielectric constant, dielectric loss, relaxation time

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1107 Modelling the Tensile Behavior of Plasma Sprayed Freestanding Yttria Stabilized Zirconia Coatings

Authors: Supriya Patibanda, Xiaopeng Gong, Krishna N. Jonnalagadda, Ralph Abrahams

Abstract:

Yttria stabilized zirconia (YSZ) is used as a top coat in thermal barrier coatings in high-temperature turbine/jet engine applications. The mechanical behaviour of YSZ depends on the microstructural features like crack density and porosity, which are a result of coating method. However, experimentally ascertaining their individual effect is difficult due to the inherent challenges involved like material synthesis and handling. The current work deals with the development of a phenomenological model to replicate the tensile behavior of air plasma sprayed YSZ obtained from experiments. Initially, uniaxial tensile experiments were performed on freestanding YSZ coatings of ~300 µm thick for different crack densities and porosities. The coatings exhibited a nonlinear behavior and also a huge variation in strength values. With the obtained experimental tensile curve as a base and crack density and porosity as prime variables, a phenomenological model was developed using ABAQUS interface with new user material defined employing VUMAT sub routine. The relation between the tensile stress and the crack density was empirically established. Further, a parametric study was carried out to investigate the effect of the individual features on the non-linearity in these coatings. This work enables to generate new coating designs by varying the key parameters and predicting the mechanical properties with the help of a simulation, thereby minimizing experiments.

Keywords: crack density, finite element method, plasma sprayed coatings, VUMAT

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1106 Physical Properties and Elastic Studies of Fluoroaluminate Glasses Based on Alkali

Authors: C. Benhamideche

Abstract:

Fluoroaluminate glasses have been reported as the earliest heavy metal fluoride glasses. By comparison with flurozirconate glasses, they offer a set of similar optical features, but also some differences in their elastic and chemical properties. In practice they have been less developed because their stability against devitrification is smaller than that of the most stable fluoroziconates. The purpose of this study was to investigate glass formation in systems AlF3-YF3-PbF2-MgF2-MF2 (M= Li, Na, K). Synthesis was implemented at room atmosphere using the ammonium fluoride processing. After fining, the liquid was into a preheated brass mold, then annealed below the glass transition temperature for several hours. The samples were polished for optical measurements. Glass formation has been investigated in a systematic way, using pseudo ternary systems in order to allow parameters to vary at the same time. We have chosen the most stable glass compositions for the determination of the physical properties. These properties including characteristic temperatures, density and proprieties elastic. Glass stability increases in multicomponent glasses. Bulk samples have been prepared for physical characterization. These glasses have a potential interest for passive optical fibers because they are less sensitive to water attack than ZBLAN glass, mechanically stronger. It is expected they could have a larger damage threshold for laser power transmission.

Keywords: fluoride glass, aluminium fluoride, thermal properties, density, proprieties elastic

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1105 Influence of Molecular and Supramolecular Structure on Thermally Stimulated Short-Circuit Currents in Polyvinylidene Fluoride Films

Authors: Temnov D., Volgina E., Gerasimov D.

Abstract:

Relaxation processes in polyvinylidene fluoride (PVDF) films were studied by the method of thermally stimulated fractional polarization currents (TSTF). The films were obtained by extrusion of a polymer melt followed by isometric annealing. PVDF granules of the Kynar-720 brand (Atofina Chemicals, USA) with a molecular weight of Mw=190,000 g•mol-1 were used for the manufacture of films. The annealing temperature was varied in the range from 120 °C to 170 °C in increments of 10 °C. The dependences of the degree of crystallinity of films (χ) and the intensity of thermally stimulated depolarization currents on the annealing temperature (Toc) are investigated. The TSTF spectra were obtained at the TSC II facility (Setaram, France). Measurements were carried out in a helium atmosphere, and the values of currents were determined by a Keithley electrometer. The annealed PVDF films were polarized at an electric field strength of 100 V/mm at a temperature of 31°C, after which they were cooled to 26°C, at which they were kept for 1 minute. During depolarization, the external field was removed, and the short-circuit sample was cooled to 0°C. The thermally stimulated short-circuit current was recorded during linear heating. Relaxation processes in PVDF films were studied in the temperature range from 0 – 70 °C. It is shown that the intensity curve of the peaks of TST FP has a course that is the reverse of the dependence of the degree of crystallinity on the annealing temperature. This allows us to conclude that the relaxation processes occurring in PVDF in the 35°C region are associated with the amorphous part of the structure of PVDF films between the layers of the spherulite crystalline phase.

Keywords: molecular and supramolecular structure, thermally stimulated currents, polyvinylidene fluoride films, relaxation processes

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1104 Determination of MDA by HPLC in Blood of Levofloxacin Treated Rats

Authors: D. S. Mohale, A. P. Dewani, A. S.tripathi, A. V. Chandewar

Abstract:

Present work demonstrates the applicability of high-performance liquid chromatography (HPLC) with UV-Vis detection for the quantification of malondialdehyde as malondialdehyde-thiobarbituric acid complex (MDA-TBA) in-vivo in rats. The HPLC method for MDA-TBA was achieved by isocratic mode on a reverse-phase C18 column (250mm×4.6mm) at a flow rate of 1.0mLmin−1 followed by detection at 532 nm. The chromatographic conditions were optimized by varying the concentration and pH of water followed by changes in percentage of organic phase optimal mobile phase consisted of mixture of water (0.2% triethylamine pH adjusted to 2.3 by ortho-phosphoric acid) and acetonitrile in ratio (80:20v/v). The retention time of MDA-TBA complex was 3.7 min. The developed method was sensitive as limit of detection and quantification (LOD and LOQ) for MDA-TBA complex were (standard deviation and slope of calibration curve) 110 ng/ml and 363 ng/ml respectively. Calibration studies were done by spiking MDA into rat plasma at concentrations ranging from 500 to 1000 ng/ml. The precision of developed method measured in terms of relative standard deviations for intra-day and inter-day studies was 1.6–5.0% and 1.9–3.6% respectively. The HPLC method was applied for monitoring MDA levels in rats subjected to chronic treatment of levofloxacin (LEV) (5mg/kg/day) for 21 days. Results were compared by findings in control group rats. Mean peak areas of both study groups was subjected for statistical treatment to unpaired student t-test to find p-values. The p value was <0.001 indicating significant results and suggesting increased MDA levels in rats subjected to chronic treatment of LEV of 21 days.

Keywords: malondialdehyde-thiobarbituric acid complex, levofloxacin, HPLC, oxidative stress

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1103 Using Predictive Analytics to Identify First-Year Engineering Students at Risk of Failing

Authors: Beng Yew Low, Cher Liang Cha, Cheng Yong Teoh

Abstract:

Due to a lack of continual assessment or grade related data, identifying first-year engineering students in a polytechnic education at risk of failing is challenging. Our experience over the years tells us that there is no strong correlation between having good entry grades in Mathematics and the Sciences and excelling in hardcore engineering subjects. Hence, identifying students at risk of failure cannot be on the basis of entry grades in Mathematics and the Sciences alone. These factors compound the difficulty of early identification and intervention. This paper describes the development of a predictive analytics model in the early detection of students at risk of failing and evaluates its effectiveness. Data from continual assessments conducted in term one, supplemented by data of student psychological profiles such as interests and study habits, were used. Three classification techniques, namely Logistic Regression, K Nearest Neighbour, and Random Forest, were used in our predictive model. Based on our findings, Random Forest was determined to be the strongest predictor with an Area Under the Curve (AUC) value of 0.994. Correspondingly, the Accuracy, Precision, Recall, and F-Score were also highest among these three classifiers. Using this Random Forest Classification technique, students at risk of failure could be identified at the end of term one. They could then be assigned to a Learning Support Programme at the beginning of term two. This paper gathers the results of our findings. It also proposes further improvements that can be made to the model.

Keywords: continual assessment, predictive analytics, random forest, student psychological profile

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1102 Development of PSS/E Dynamic Model for Controlling Battery Output to Improve Frequency Stability in Power Systems

Authors: Dae-Hee Son, Soon-Ryul Nam

Abstract:

The power system frequency falls when disturbance such as rapid increase of system load or loss of a generating unit occurs in power systems. Especially, increase in the number of renewable generating units has a bad influence on the power system because of loss of generating unit depending on the circumstance. Conventional technologies use frequency droop control battery output for the frequency regulation and balance between supply and demand. If power is supplied using the fast output characteristic of the battery, power system stability can be further more improved. To improve the power system stability, we propose battery output control using ROCOF (Rate of Change of Frequency) in this paper. The bigger the power difference between the supply and the demand, the bigger the ROCOF drops. Battery output is controlled proportionally to the magnitude of the ROCOF, allowing for faster response to power imbalances. To simulate the control method of battery output system, we develop the user defined model using PSS/E and confirm that power system stability is improved by comparing with frequency droop control.

Keywords: PSS/E user defined model, power deviation, frequency droop control, ROCOF (rate of change of frequency)

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1101 Management of Urban Watering: A Study of Appliance of Technologies and Legislation in Goiania, Brazil

Authors: Vinicius Marzall, Jussanã Milograna

Abstract:

The urban drainwatering remains a major challenge for most of the Brazilian cities. Not so different of the most part, Goiania, a state capital located in Midwest of the country has few legislations about the subject matter and only one registered solution of compensative techniques for drainwater. This paper clam to show some solutions which are adopted in other Brazilian cities with consolidated legislation, suggesting technics about detention tanks in a building sit. This study analyzed and compared the legislation of Curitiba, Porto Alegre e Sao Paulo, with the actual legislation and politics of Goiania. After this, were created models with adopted data for dimensioning the size of detention tanks using the envelope curve method considering synthetic series for intense precipitations and building sits between 250 m² and 600 m², with an impermeabilization tax of 50%. The results showed great differences between the legislation of Goiania and the documentation of the others cities analyzed, like the number of techniques for drainwatering applied to the reality of the cities, educational actions to awareness the population about care the water courses and political management by having a specified funds for drainwater subjects, for example. Besides, the use of detention tank showed itself practicable, have seen that the occupation of the tank is minor than 3% of the building sit, whatever the size of the terrain, granting the exit flow to pre-occupational taxes in extreme rainfall events. Also, was developed a linear equation to measure the detention tank based in the size of the building sit in Goiania, making simpler the calculation and implementation for non-specialized people.

Keywords: clean technology, legislation, rainwater management, urban drainwater

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1100 Did Nature of Job Matters - Impact of Perceived Job Autonomy on Turnover Intention in Sales and Marketing Managers: Moderating Effect of Procedural and Distributive Justice

Authors: Muhammad Babar Shahzad

Abstract:

The purpose of our study is to investigate the relationship between perceived job autonomy and turnover intention in sales & marketing staff. Perceived job autonomy is considered one of most studied dimension of Job Characteristic Model. But still there is a confusion in scholars about predictive role of perceived job autonomy in turnover intention. In line of more complex research on this relation, we investigated the relationship between perceived job autonomy and turnover intention. Did nature of job have any impact on this relationship. On the call of different authors we take interactive effect of perceived job autonomy and procedural justice on turnover intention. Predictive role of distributive justice to employee outcomes is not deniable. But predictive role of distributive justice will be prone in different contextual influences. Interactive role of distributive justice and perceived job autonomy is also not tested before. We collected date from 279 marketing and sales managers working in financial institution, FMCG industries, Pharamesutical Industry & Bank. Strong and direct negative relation was found in perceived job autonomy, distributive justice & procedural justice on turnover intention. Distributive and procedural justice is also amplifying the negative relationship of perceived job autonomy and turnover intention. Limitation and future direction for research is also discussed.

Keywords: perceived job autonomy, turnover intention, procedural justice, distributive job

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1099 An Approach to Apply Kernel Density Estimation Tool for Crash Prone Location Identification

Authors: Kazi Md. Shifun Newaz, S. Miaji, Shahnewaz Hazanat-E-Rabbi

Abstract:

In this study, the kernel density estimation tool has been used to identify most crash prone locations in a national highway of Bangladesh. Like other developing countries, in Bangladesh road traffic crashes (RTC) have now become a great social alarm and the situation is deteriorating day by day. Today’s black spot identification process is not based on modern technical tools and most of the cases provide wrong output. In this situation, characteristic analysis and black spot identification by spatial analysis would be an effective and low cost approach in ensuring road safety. The methodology of this study incorporates a framework on the basis of spatial-temporal study to identify most RTC occurrence locations. In this study, a very important and economic corridor like Dhaka to Sylhet highway has been chosen to apply the method. This research proposes that KDE method for identification of Hazardous Road Location (HRL) could be used for all other National highways in Bangladesh and also for other developing countries. Some recommendations have been suggested for policy maker to reduce RTC in Dhaka-Sylhet especially in black spots.

Keywords: hazardous road location (HRL), crash, GIS, kernel density

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1098 Experimental Investigation on the Mechanical Behaviour of Three-Leaf Masonry Walls under In-Plane Loading

Authors: Osama Amer, Yaser Abdel-Aty, Mohamed Abd El Hady

Abstract:

The present paper illustrates an experimental approach to provide understanding of the mechanical behavior and failure mechanisms of different typologies of unreinforced three-leaf masonry walls of historical Islamic architectural heritage in Egypt. The main objective of this study is to investigate the propagation of possible cracking, ultimate load, deformations and failure mechanisms. Experimental data on interface-shear and compression tests on large scale three-leaf masonry wallets are provided. The wallets were built basically of Egyptian limestone and modified lime mortar. External wallets were built of stone blocks while the inner leaf was built of rubble limestone. Different loading conditions and dimensions of core layer for two types of collar joints (with and without shear keys) are considered in the tests. Mechanical properties of the constituent materials of masonry were tested and a database of characteristic properties was created. The results of the experiments will highlight the properties, force-displacement curves, stress distribution of multiple-leaf masonry walls contributing to the derivation of rational design rules and validation of numerical models.

Keywords: masonry, three-leaf walls, mechanical behavior, testing, architectural heritage

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1097 Simulation Analysis of a Full-Scale Five-Story Building with Vibration Control Dampers

Authors: Naohiro Nakamura

Abstract:

Analysis methods to accurately estimate the behavior of buildings when earthquakes occur is very important for improving the seismic safety of such buildings. Recently, the use of damping devices has increased significantly and there is a particular need to appropriately evaluate the behavior of buildings with such devices during earthquakes in the design stage. At present, however, the accuracy of the analysis evaluations is not sufficient. One reason is that the accuracy of current analysis methods has not been appropriately verified because there is very limited data on the behavior of actual buildings during earthquakes. Many types of shaking table test of large structures are performed at the '3-Dimensional Full-Scale Earthquake Testing Facility' (nicknamed 'E-Defense') operated by the National Research Institute of Earth Science and Disaster Prevention (NIED). In this study, simulations using 3- dimensional analysis models were conducted on shaking table test of a 5-story steel-frame structure with dampers. The results of the analysis correspond favorably to the test results announced afterward by the committee. However, the suitability of the parameters and models used in the analysis and the influence they had on the responses remain unclear. Hence, we conducted additional analysis and studies on these models and parameters. In this paper, outlines of the test are shown and the utilized analysis model is explained. Next, the analysis results are compared with the test results. Then, the additional analyses, concerning with the hysteresis curve of the dampers and the beam-end stiffness of the frame, are investigated.

Keywords: three-dimensional analysis, E-defense, full-scale experimen, vibration control damper

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1096 Fuzzy Inference System for Determining Collision Risk of Ship in Madura Strait Using Automatic Identification System

Authors: Emmy Pratiwi, Ketut B. Artana, A. A. B. Dinariyana

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Madura Strait is considered as one of the busiest shipping channels in Indonesia. High vessel traffic density in Madura Strait gives serious threat due to navigational safety in this area, i.e. ship collision. This study is necessary as an attempt to enhance the safety of marine traffic. Fuzzy inference system (FIS) is proposed to calculate risk collision of ships. Collision risk is evaluated based on ship domain, Distance to Closest Point of Approach (DCPA), and Time to Closest Point of Approach (TCPA). Data were collected by utilizing Automatic Identification System (AIS). This study considers several ships’ domain models to give the characteristic of marine traffic in the waterways. Each encounter in the ship domain is analyzed to obtain the level of collision risk. Risk level of ships, as the result in this study, can be used as guidance to avoid the accident, providing brief description about safety traffic in Madura Strait and improving the navigational safety in the area.

Keywords: automatic identification system, collision risk, DCPA, fuzzy inference system, TCPA

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1095 Triangular Geometric Feature for Offline Signature Verification

Authors: Zuraidasahana Zulkarnain, Mohd Shafry Mohd Rahim, Nor Anita Fairos Ismail, Mohd Azhar M. Arsad

Abstract:

Handwritten signature is accepted widely as a biometric characteristic for personal authentication. The use of appropriate features plays an important role in determining accuracy of signature verification; therefore, this paper presents a feature based on the geometrical concept. To achieve the aim, triangle attributes are exploited to design a new feature since the triangle possesses orientation, angle and transformation that would improve accuracy. The proposed feature uses triangulation geometric set comprising of sides, angles and perimeter of a triangle which is derived from the center of gravity of a signature image. For classification purpose, Euclidean classifier along with Voting-based classifier is used to verify the tendency of forgery signature. This classification process is experimented using triangular geometric feature and selected global features. Based on an experiment that was validated using Grupo de Senales 960 (GPDS-960) signature database, the proposed triangular geometric feature achieves a lower Average Error Rates (AER) value with a percentage of 34% as compared to 43% of the selected global feature. As a conclusion, the proposed triangular geometric feature proves to be a more reliable feature for accurate signature verification.

Keywords: biometrics, euclidean classifier, features extraction, offline signature verification, voting-based classifier

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1094 Effects of Rice Husk Ash on the Properties of Scrap Tyre Steel Fiber Reinforced High Performance Concrete (RHA-STSFRHAC)

Authors: Isyaka Abdulkadir, Egbe-Ngu Ntui Ogork

Abstract:

This research aims to investigate the effect of Rice Husk Ash (RHA) on Scrap Tyre Steel Fiber Reinforced High Performance Concrete (STSFRHPC). RHA was obtained by control burning of rice husk in a kiln to a temperature of 650-700oC and when cooled sieved through 75µm sieve and characterized. The effect of RHA were investigated on grade 50 STSFRHPC of 1:1.28:1.92 with water cement ratio of 0.39 at additions of Scrap Tyre Steel Fiber (STSF) of 1.5% by volume of concrete and partial replacement of cement with RHA at percentages of 0, 5, 10, 15 and 20. The fresh concrete was tested for slump while the hardened concrete was tested for compressive and splitting tensile strengths respectively at curing ages of 3, 7, 28 and 56 days in accordance with standard procedure. Results of RHA-STSFRHPC indicated a reduction in slump and compressive strength with increase in RHA content, while splitting tensile strength increased with RHA replacement up to 10% and reduction in strength above 10% RHA content. The 28 days compressive strength of RHA-STSFRHPC with up to 10% RHA attained the desired characteristic strength of 50N/mm2 and therefore up to 10% RHA is considered as the optimum replacement dosage in STSFRHPC-RHA.

Keywords: compressive strength, high performance concrete, rice husk ash, scrap tyre steel fibers

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1093 Stress Analysis of Water Wall Tubes of a Coal-fired Boiler during Soot Blowing Operation

Authors: Pratch Kittipongpattana, Thongchai Fongsamootr

Abstract:

This research aimed to study the influences of a soot blowing operation and geometrical variables to the stress characteristic of water wall tubes located in soot blowing areas which caused the boilers of Mae Moh power plant to lose their generation hour. The research method is divided into 2 parts (a) measuring the strain on water wall tubes by using 3-element rosette strain gages orientation during a full capacity plant operation and in periods of soot blowing operations (b) creating a finite element model in order to calculate stresses on tubes and validating the model by using experimental data in a steady state plant operation. Then, the geometrical variables in the model were changed to study stresses on the tubes. The results revealed that the stress was not affected by the soot blowing process and the finite element model gave the results 1.24% errors from the experiment. The geometrical variables influenced the stress, with the most optimum tubes design in this research reduced the average stress from the present design 31.28%.

Keywords: boiler water wall tube, finite element, stress analysis, strain gage rosette

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1092 Numerical and Experimental Studies on the Characteristic of the Air Distribution in the Wind-Box of a Circulating Fluidized Bed Boiler

Authors: Xiaozhou Liu, Guangyu Zhu, Yu Zhang, Hongwei Wu

Abstract:

The wind-box is one of the important components of a Circulating Fluidized Bed (CFB) boiler. The uniformity of air flow in the wind-box of is very important for highly efficient operation of the CFB boiler. Non-uniform air flow distribution within the wind-box can reduce the boiler's thermal efficiency, leading to higher energy consumptions. An effective measure to solve this problem is to install an air flow distributing device in the wind-box. In order to validate the effectiveness of the air flow distributing device, visual and velocity distribution uniformity experiments have been carried out under five different test conditions by using a 1:64 scale model of a 220t/hr CFB boiler. It has been shown that the z component of flow velocity remains almost the same at control cross-sections of the wind-box, with a maximum variation of less than 10%. Moreover, the same methodology has been carried out to a full-scale 220t/hr CFB boiler. The hot test results depict that the thermal efficiency of the boiler has increased from 85.71% to 88.34% when tested with an air flow distributing device in place, which is equivalent to a saving of 5,000 tons of coal per year. The economic benefits of this energy-saving technology have been shown to be very significant, which clearly demonstrates that the technology is worth applying and popularizing.

Keywords: circulating fluidized bed, CFB, wind-box, air flow distributing device, visual experiment, velocity distribution uniformity experiment, hot test

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1091 Analysis of Vibratory Signals Based on Local Mean Decomposition (LMD) for Rolling Bearing Fault Diagnosis

Authors: Toufik Bensana, Medkour Mihoub, Slimane Mekhilef

Abstract:

The use of vibration analysis has been established as the most common and reliable method of analysis in the field of condition monitoring and diagnostics of rotating machinery. Rolling bearings cover a broad range of rotary machines and plays a crucial role in the modern manufacturing industry. Unfortunately, the vibration signals collected from a faulty bearing are generally nonstationary, nonlinear and with strong noise interference, so it is essential to obtain the fault features correctly. In this paper, a novel numerical analysis method based on local mean decomposition (LMD) is proposed. LMD decompose the signal into a series of product functions (PFs), each of which is the product of an envelope signal and a purely frequency modulated FM signal. The envelope of a PF is the instantaneous amplitude (IA), and the derivative of the unwrapped phase of a purely flat frequency demodulated (FM) signal is the IF. After that, the fault characteristic frequency of the roller bearing can be extracted by performing spectrum analysis to the instantaneous amplitude of PF component containing dominant fault information. The results show the effectiveness of the proposed technique in fault detection and diagnosis of rolling element bearing.

Keywords: fault diagnosis, rolling element bearing, local mean decomposition, condition monitoring

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1090 Fatigue Life Estimation of Spiral Welded Waterworks Pipelines

Authors: Suk Woo Hong, Chang Sung Seok, Jae Mean Koo

Abstract:

Recently, the welding is widely used in modern industry for joining the structures. However, the waterworks pipes are exposed to the fatigue load by cars, earthquake and etc because of being buried underground. Moreover, the residual stress exists in weld zone by welding process and it is well known that the fatigue life of welded structures is degraded by residual stress. Due to such reasons, the crack can occur in the weld zone of pipeline. In this case, The ground subsidence or sinkhole can occur, if the soil and sand are washed down by fluid leaked from the crack of water pipe. These problems can lead to property damage and endangering lives. For these reasons, the estimation of fatigue characteristics for water pipeline weld zone is needed. Therefore, in this study, for fatigue characteristics estimation of spiral welded waterworks pipe, ASTM standard specimens and Curved Plate specimens were collected from the spiral welded waterworks pipe and the fatigue tests were performed. The S-N curves of each specimen were estimated, and then the fatigue life of weldment Curved Plate specimen was predicted by theoretical and analytical methods. After that, the weldment Curved Plate specimens were collected from the pipe and verification fatigue tests were performed. Finally, it was verified that the predicted S-N curve of weldment Curved Plate specimen was good agreement with fatigue test data.

Keywords: spiral welded pipe, prediction fatigue life, endurance limit modifying factors, residual stress

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1089 Oral Examination: An Important Adjunct to the Diagnosis of Dermatological Disorders

Authors: Sanjay Saraf

Abstract:

The oral cavity can be the site for early manifestations of mucocutaneous disorders (MD) or the only site for occurrence of these disorders. It can also exhibit oral lesions with simultaneous associated skin lesions. The MD involving the oral mucosa commonly presents with signs such as ulcers, vesicles and bullae. The unique environment of the oral cavity may modify these signs of the disease, thereby making the clinical diagnosis an arduous task. In addition to the unique environment of oral cavity, the overlapping of the signs of various mucocutaneous disorders, also makes the clinical diagnosis more intricate. The aim of this review is to present the oral signs of dermatological disorders having common oral involvement and emphasize their importance in early detection of the systemic disorders. The aim is also to highlight the necessity of oral examination by a dermatologist while examining the skin lesions. Prior to the oral examination, it must be imperative for the dermatologists and the dental clinicians to have the knowledge of oral anatomy. It is also important to know the impact of various diseases on oral mucosa, and the characteristic features of various oral mucocutaneous lesions. An initial clinical oral examination is may help in the early diagnosis of the MD. Failure to identify the oral manifestations may reduce the likelihood of early treatment and lead to more serious problems. This paper reviews the oral manifestations of immune mediated dermatological disorders with common oral manifestations.

Keywords: dermatological investigations, genodermatosis, histological features, oral examination

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1088 Big Data in Telecom Industry: Effective Predictive Techniques on Call Detail Records

Authors: Sara ElElimy, Samir Moustafa

Abstract:

Mobile network operators start to face many challenges in the digital era, especially with high demands from customers. Since mobile network operators are considered a source of big data, traditional techniques are not effective with new era of big data, Internet of things (IoT) and 5G; as a result, handling effectively different big datasets becomes a vital task for operators with the continuous growth of data and moving from long term evolution (LTE) to 5G. So, there is an urgent need for effective Big data analytics to predict future demands, traffic, and network performance to full fill the requirements of the fifth generation of mobile network technology. In this paper, we introduce data science techniques using machine learning and deep learning algorithms: the autoregressive integrated moving average (ARIMA), Bayesian-based curve fitting, and recurrent neural network (RNN) are employed for a data-driven application to mobile network operators. The main framework included in models are identification parameters of each model, estimation, prediction, and final data-driven application of this prediction from business and network performance applications. These models are applied to Telecom Italia Big Data challenge call detail records (CDRs) datasets. The performance of these models is found out using a specific well-known evaluation criteria shows that ARIMA (machine learning-based model) is more accurate as a predictive model in such a dataset than the RNN (deep learning model).

Keywords: big data analytics, machine learning, CDRs, 5G

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1087 Transdermal Therapeutic System of Lercanıdipine Hydrochloride: Fabrication and in Vivo Evaluation

Authors: Jiji Jose, R. Narayanacharyulu, Molly Mathew, Jisha Prems

Abstract:

Introduction: Lercanidipine hydrochloride (LD), an effective calcium channel blocker, widely used for the treatment of chronic stable angina and hypertension seems to be potential transdermal therapeutic system candidate, mainly due to its low oral bio availability, short half life and high first-pass metabolism. Objective: To develop transdermal therapeutic systems for LD and to evaluate its in vivo performance in rabbits. Methodology: Transdermal patches of LD were formulated using the polymer blend of eudragit RL100 (ERL) and polyvinyl pyrolidone (PVP) by casting method Propylene glycol (PG) and tween 80 were used as plasticizer and permeation enhancer respectively. The pharmaco kinetic parameters of LD after the administration of transdermal patches was compared with that of oral administration. The study was carried out in a two way crossover design in male New Zealand albino rabbits. Results: The formulation with ERL: PVP ratio 1:4 with 15% w/w PG as plasticizer and 4% w/w tween 80 as permeation enhancer showed the best drug release results. The pharmacokinetic parameters such as Cmax, tmax, mean residence time (MRT) and area under the curve (AUC 0-∞) were significantly different following transdermal administration compared to oral administration. The terminal half life of transdermally administered LD was found to similar that of oral administration. A sustained drug release over a period of 24 hrs was observed after transdermal administration. Conclusion: The fabricated transdermal delivery system have the potential to provide controlled and extended drug release, better bio availability and thus, this may improve the patient compliance.

Keywords: transdermal therapeutic system, lercanidipine hydrochloride, eudragit, skinpermeation

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1086 Biobased Polyurethane Derived from Transesterified Castor Oil: Synthesis and Charecterization

Authors: Sonalee Das, Smita Mohanty, S. K. Nayak

Abstract:

Recent years has witnessed the increasing demand for natural resources and products in polyurethane synthesis because of global warming, sustainable development and oil crisis. For this purpose, different plant oils such as soybean oil, castor oil and linseed oil are extensively used. Moreover, the isocyanate used for the synthesis of polyurethane is derived from petroleum resources. In this present work attempts have been made for the successful synthesis of biobased isocyanate from castor oil with partially biobased isocyanate in presence of catalyst dibutyltin dilaurate (DBTDL). The goal of the present study was to investigate the thermal, mechanical, morphological and chemical properties of the synthesized polyurethane in terms of castor oil modification. The transesterified polyol shows broad and higher hydroxyl value as compared to castor oil which was confirmed by FTIR studies. The FTIR studies also revealed the successful synthesis of bio based polyurethane by showing characteristic peaks at 3300cm-1, 1715cm-1 and 1532cm-1 respectively. The TGA results showed three step degradation mechanism for the synthesized polyurethane from modified and unmodified castor oil. However, the modified polyurethane exhibited higher degradation temperature as compared to unmodified one. The mechanical properties also demonstrated higher tensile strength for modified polyurethane as compared to unmodified one.

Keywords: castor oil, partially biobased Isocyanate, polyurethane synthesis, FTIR

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1085 ‘Groupitizing’ – A Key Factor in Math Learning Disabilities

Authors: Michal Wolk, Bat-Sheva Hadad, Orly Rubinsten

Abstract:

Objective: The visuospatial perception system process that allows us to decompose and recompose small quantities into a whole is often called “groupitizing.” Previous studies have been found that adults use groupitizing processes in quantity estimation tasks and link this ability of subgroups recognition to arithmetic proficiency. This pilot study examined if adults with math difficulties benefit from visuospatial grouping cues when asked to estimate the quantity of a given set. It also compared the tipping point in which a significant improvement occurs in adults with typical development compared to adults with math difficulties. Method: In this pilot research, we recruited adults with low arithmetic abilities and matched controls. Participants were asked to estimate the quantity of a given set. Different grouping cues were displayed (space, color, or none) with different visual configurations (different quantities-different shapes, same quantities- different shapes, same quantities- same shapes). Results: Both groups showed significant performance improvement when grouping cues appeared. However, adults with low arithmetic abilities benefited from the grouping cues already in very small quantities as four. Conclusion: impaired perceptual groupitizing abilities may be a characteristic of low arithmetic abilities.

Keywords: groupitizing, math learning disability, quantity estimation, visual perception system

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1084 Nature of a Supercritical Mesophase

Authors: Hamza Javar Magnier, Leslie V. Woodcock

Abstract:

It has been reported that at temperatures above the critical there is no “continuity of liquid and gas”, as originally hypothesized by van der Waals. Rather, both gas and liquid phases, with characteristic properties as such, extend to supercritical temperatures. Each phase is bounded by the locus of a percolation transition, i.e. a higher-order thermodynamic phase change associated with percolation of gas clusters in a large void, or liquid interstitial vacancies in a large cluster. Between these two-phase bounds, it is reported there exists a mesophase that resembles an otherwise homogeneous dispersion of gas micro-bubbles in liquid (foam) and a dispersion of liquid micro-droplets in gas (mist). Such a colloidal-like state of a pure one-component fluid represents a hitherto unchartered equilibrium state of matter besides pure solid, liquid or gas. Here we provide compelling evidence, from molecular dynamics (MD) simulations, for the existence of this supercritical mesophase and its colloidal nature. We report preliminary results of computer simulations for a model fluid using a simplistic representation of atoms or molecules, i.e. a hard-core repulsion with an attraction so short that the atoms are referred to as “adhesive spheres”. Molecular clusters, and hence percolation transitions, are unambiguously defined. Graphics of color-coded clusters show colloidal characteristics of the supercritical mesophase.

Keywords: critical phenomena, mesophase, supercritical, square-well, critical parameters

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1083 A Comparative Study of Wellness Among Sportsmen and Non Sportsmen

Authors: Jaskaran Singh Sidhu

Abstract:

Aim: The purpose of this study is to find the relationship between wellness among sportsmen and non sportsmen. Methodology: The present study is an experimental study for 80 senior secondary volleyball players of 16-19 years of age from Ludhiana District of Punjab (India), and 80 non-sportsperson were taken from senior secondary school of Ludhiana district. The sample for this study was taken through a random sampling technique. Tools: A five point scale havinf 50 items was used to acess the wellness Statistical Analysis: To find out the relationship among the variables exists or not, a t-test was used to test the significance of the difference between the means. Statistics for each characteristic were calculated; Mean, Standard deviation, Standard error of Mean. Data were analyzed using SPSS (statistical package for the social sciences). Statistical significance was set at p < 0.05. Results: Substantial deviations were noted at p<0.5 in the totality of wellness. Sportsmen show significant differences exist at p<0.5 in three parameters of wellness i.e., physical wellness, mental wellness, and social wellness. In spiritual and emotional wellness attributes, non-sportsmen shows significant difference at p<0.5. Conclusion: From the data interpretation it reflects that overall wellness can be improved by participation in sports. It further noted in study that participation in sports promote the attributes of wellness i.e., physical wellness, mental wellness, emotional wellness and social wellness.

Keywords: physical, mental, social, emotional, wellness, spiritual

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1082 Estimations of Spectral Dependence of Tropospheric Aerosol Single Scattering Albedo in Sukhothai, Thailand

Authors: Siriluk Ruangrungrote

Abstract:

Analyses of available data from MFR-7 measurement were performed and discussed on the study of tropospheric aerosol and its consequence in Thailand. Since, ASSA (w) is one of the most important parameters for a determination of aerosol effect on radioactive forcing. Here the estimation of w was directly determined in terms of the ratio of aerosol scattering optical depth to aerosol extinction optical depth (ωscat/ωext) without any utilization of aerosol computer code models. This is of benefit for providing the elimination of uncertainty causing by the modeling assumptions and the estimation of actual aerosol input data. Diurnal w of 5 cloudless-days in winter and early summer at 5 distinct wavelengths of 415, 500, 615, 673 and 870 nm with the consideration of Rayleigh scattering and atmospheric column NO2 and Ozone contents were investigated, respectively. Besides, the tendency of spectral dependence of ω representing two seasons was observed. The characteristic of spectral results reveals that during wintertime the atmosphere of the inland rural vicinity for the period of measurement possibly dominated with a lesser amount of soil dust aerosols loading than one in early summer. Hence, the major aerosol loading particularly in summer was subject to a mixture of both soil dust and biomass burning aerosols.

Keywords: aerosol scattering optical depth, aerosol extinction optical depth, biomass burning aerosol, soil dust aerosol

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1081 Numerical and Experimental Analysis of Stiffened Aluminum Panels under Compression

Authors: Ismail Cengiz, Faruk Elaldi

Abstract:

Within the scope of the study presented in this paper, load carrying capacity and buckling behavior of a stiffened aluminum panel designed by adopting current ‘buckle-resistant’ design application and ‘Post –Buckling’ design approach were investigated experimentally and numerically. The test specimen that is stabilized by Z-type stiffeners and manufactured from aluminum 2024 T3 Clad material was test under compression load. Buckling behavior was observed by means of 3 – dimensional digital image correlation (DIC) and strain gauge pairs. The experimental study was followed by developing an efficient and reliable finite element model whose ability to predict behavior of the stiffened panel used for compression test is verified by compering experimental and numerical results in terms of load – shortening curve, strain-load curves and buckling mode shapes. While finite element model was being constructed, non-linear behaviors associated with material and geometry was considered. Finally, applicability of aluminum stiffened panel in airframe design against to composite structures was evaluated thorough the concept of ‘Structural Efficiency’. This study reveals that considerable amount of weight saving could be gained if the concept of ‘post-buckling design’ is preferred to the already conventionally used ‘buckle resistant design’ concept in aircraft industry without scarifying any of structural integrity under load spectrum.

Keywords: post-buckling, stiffened panel, non-linear finite element method, aluminum, structural efficiency

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1080 An Exploratory Study Applied to the Accessibility of Museums in the UK

Authors: Sifan Guo, Xuesen Zheng

Abstract:

Visitors as the vital research group have been mentioned in high frequency in the field of museum studies. With the rise of the New Museology Movement, new challenges in the museum appeared, ranging from how to eliminate the cliché class prejudices in museums to how to make visitor-oriented museums more welcome. In line with this new situation, to create a successful visiting experience is the focus of museums in today. National museums as tourist attractions always attract flooded attention, however the local museums may have the different situations. The residents could be one of the main visitors to the local museums how to attract them returned should be considered here. There are various people with different cultural, education and religion backgrounds, it is necessary to keep the balance of the education and entertainment to reach visitors’ expectations. Regarding these questions, a mixed methods research approach has been adopted: observations, tracking and questionnaires. Based on analysing some museums’ cases in the UK, it can be argued that: 1) Audiences’ accessibility support their options and judgments during the visiting. 2) Highly inclusive architecture and narrative expressions could encourage the visitors to proceed deeply understanding and alleviate conflicts. In addition, the main characteristics of the local museums and the interlinks between museums and urban renaissance will be clarified. The conclusion informs not only practical suggestions for reachable characteristic design, but also potential future research subjects.

Keywords: accessibility, challenging visitors, new museology movement, visiting experience

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1079 The Factors Constitute the Interaction between Teachers and Students: An Empirical Study at the Notion of Framing

Authors: Tien-Hui Chiang

Abstract:

The code theory, proposed by Basil Bernstein, indicates that framing can be viewed as the core element in constituting the phenomenon of cultural reproduction because it is able to regulate the transmission of pedagogical information. Strong framing increases the social relation boundary between a teacher and pupils, which obstructs information transmission, so that in order to improve underachieving students’ academic performances, teachers need to reduce to strength of framing. Weak framing enables them to transform academic knowledge into commonsense knowledge in daily life language. This study posits that most teachers would deliver strong framing due to their belief mainly confined within the aspect of instrumental rationality that deprives their critical minds. This situation could make them view the normal distribution bell curve of students’ academic performances as a natural outcome. In order to examine the interplay between framing, instrumental rationality and pedagogical action, questionnaires were completed by over 5,000 primary school teachers in Henan province, China, who were stratified sample. The statistical results show that most teachers employed psychological concepts to measure students’ academic performances and, in turn, educational inequity was legitimatized as a natural outcome in the efficiency-led approach. Such efficiency-led minds made them perform as the agent practicing the mechanism of social control and in turn sustaining the phenomenon of cultural reproduction.

Keywords: code, cultural reproduction, framing, instrumental rationality, social relation and interaction

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