Search results for: crack investigation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5095

Search results for: crack investigation

4735 Impact of Popular Passive Physiological Diversity Drivers on Thermo-Physiology

Authors: Ilango Thiagalingam, Erwann Yvin, Gabriel Crehan, Roch El Khoury

Abstract:

An experimental investigation is carried out in order to evaluate the relevance of a customization approach of the passive thermal mannikin. The promise of this approach consists in the following assumption: physiological differences lead to distinct thermo-physiological responses that explain a part of the thermal appraisal differences between people. Categorizing people and developing an appropriate thermal mannikin for each group would help to reduce the actual dispersion on the subjective thermal comfort perception. The present investigation indicates that popular passive physiological diversity drivers such as sex, age and BMI are not the correct parameters to consider. Indeed, very little or no discriminated global thermo-physiological responses arise from the physiological classification of the population using these parameters.

Keywords: thermal comfort, thermo-physiology, customization, thermal mannikin

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4734 Cybercrime: International Police Cooperation with Europol

Authors: Daniel Suarez Alonso

Abstract:

Cybercrime is a growing international threat and a challenge for law enforcement agencies and judicial systems worldwide. International cooperation is necessary to solve this problem because cybercrime knows no borders and often involves multiple jurisdictions, being related to organised crime. The purpose of this article is to analyse international cooperation in the investigation and prosecution of cybercrime, focusing on the framework of the Regulation of the European Union Agency for Law Enforcement Cooperation (EUROPOL), cooperation that takes place between police authorities from different countries. It examines the legal and operational mechanisms in place to facilitate international cooperation in Europe in this area and assesses their effectiveness in the fight against cybercrime. In addition, the study of a Spanish investigation where cooperation with EUROPOL took place will be examined, analyzing how international cooperation was carried out to investigate and track down criminals. Lessons learned from this case will be discussed and recommendations for improving international cooperation in the fight against cybercrime will be proposed.

Keywords: Europol, international cooperation, cybercrime, computer crime, law

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4733 Investigation into Varied Inspection Utilization for Mass Customization

Authors: Trishen Naidoo, Anthony Walker, Shaniel Davrajh, Glen Bright

Abstract:

An investigation into on-line inspection was performed where research is focused on the use of varied inspection (as opposed to 100% inspection) for mass customization (MC). Manufacturers need new methods for quality control in mass customization, and these methods need to address some of the old problems such as over-inspection and bottlenecking. Due to the risks of varied inspection, many manufacturers do not implement it and rather opt for sampling methods. However, there are many advantages of varied inspection and can have applications in mass customization. A control system incorporating fuzzy logic (FL) control is used to perform the variations in inspection usage in a simulated environment. The proposed system can have a key impact in appraisal costs reduction and possibly work-in-process reduction in high variety environments.

Keywords: appraisal costs, fuzzy logic, quality control, work-in-process

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4732 Strategies of Spatial Optimization for Open Space in the Old-Age Friendly City: An Investigation of the Behavior of the Elderly in Xicheng Square in Hangzhou

Authors: Yunxiang Fang

Abstract:

With the aging trend continuing to accelerate, open space is important for the daily life of the elderly, and its old-age friendliness is worthy of attention. Based on behavioral observation and literature research, this paper studies the behavior of the elderly in urban open space. Through the investigation, classification and quantitative analysis of the activity types, time characteristics and spatial behavior order of the elderly in Xicheng Square in Hangzhou, it summarizes the square space suitable for the psychological needs, physiology and activity needs of the elderly, combined with the basis of literature research. Finally, the suggestions for the improvement of the old-age friendship of Xicheng Square are put forward, from the aspects of microclimate, safety and accessibility, space richness and service facility quality.

Keywords: behavior characteristics, old-age friendliness, open space, square

Procedia PDF Downloads 143
4731 Electrophoretic Changes in Testis and Liver of Mice after Exposure to Diclofenac Sodium

Authors: Deepak Mohan, Sushma Sharma, Mohammad Asif

Abstract:

Diclofenac sodium being one of the most common non-steroidal anti-inflammatory drugs is normally used as painkiller and to reduce inflammation. The drug is known to alter the enzymatic activities of acid and alkaline phosphatase, glutamate oxaloacetate transaminase and glutamate pyruvate transaminases. The drug also results in change in the concentration of proteins and lipids in the body. The present study is an attempt to study different biochemical changes electrophoretically due to administration of different doses of diclofenac (4mg/kg/body weight and 14mg/kg/body weight) on liver and testes of mice from 7-28 days of investigation. Homogenization of the tissue was done, supernatant separated was loaded in the gel and native polyacrylamide gel electrophoresis was conducted. Diclofenac administration resulted in alterations of all these biochemical parameters which were observed in native polyacrylamide gel electrophoretic studies. The severe degenerative changes as observed during later stages of the experiment showed correlation with increase or decrease in the activities of all the enzymes studied in the present investigation. Image analysis of gel in liver showed a decline of 7.4 and 5.3 % in low and high dose group after 7 days whereas a decline of 9.6 and 7.5% was registered after 28 days of investigation. Similar analysis for testis also showed an appreciable decline in the activity of alkaline phosphatase after 28 days. Gel analysis of serum was also performed to find a correlation in the enzymatic activities between the tissue and blood.

Keywords: diclofenac, inflammation, polyacrylamide, phosphatase

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4730 Forensics Linguistics and Phonetics: The Analysis of Language to Support Investigations

Authors: Andreas Aceranti, Simonetta Vernocchi, Marco Colorato, Kaoutar Filahi

Abstract:

This study was inspired by the necessity of giving forensic linguistics and phonetics more and more importance and the intention to explore those topics in an attempt to understand what the role of these disciplines really is in investigations of any nature. The goal is to analyze what are the achievements that those subjects have been able to reach, and what contribution they gave to the legal world; the analysis and study of those topics are supported by the recounting of real cases that have included forensic and phonetic linguistics. One of the most relevant cases is that of the Unabomber, an investigation that brought to light the importance and highlighted the importance this matter can have in difficult and time-consuming cases such as the one we have here. We also focus on the areas of expertise of those new branches of applied linguistics, focusing on what is the use of this new discipline in Italy and abroad and showing what could be the possible improvements that the Italian state could apply in order to be able to catch up with countries like Great Britain.

Keywords: forensic linguistic, forensic phonetics, investigation, criminalistics

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4729 ANSYS Investigation on Stability and Performance of a Solar Driven Inline Alpha Stirling Engine

Authors: Joseph Soliman, Youssef Attia, Khairy Megalla

Abstract:

The stable operation of an inline Stirling engine will be achieved when both engine configurations and operating conditions are optimum. This paper presents stability and performance investigation of an inline Stirling engine using ANSYS. Dynamic motion of engine pistons such as the displacer and the power piston are both obtained. For engine design, the optimum parameters are given such as engine specifications, engine characteristics and working conditions to yield the maximum efficiency and reliability. The prototype was built and tested and it is used as a validation case. The comparison of both experimental and simulation results are provided and discussed. Results were found to be encouraging to initiate a Stirling engine project for 3 kW power output. The working fluids are air, hydrogen, nitrogen and helum.

Keywords: stirling engine, solar energy, new energy, dynamic motion

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4728 Numerical Investigation of Blood Flow around a Leaflet Valve through a Perforating Vein

Authors: Zohreh Sheidaei, Farhad Sadegh Moghanlou, Rahim Vesal

Abstract:

Diseases related to leg venous system are common worldwide. An incompetent vein with deformed wall and insufficient valves affects flow field of blood and disrupts the process of blood circulating system. Having enough knowledge about the flow field through veins will help find new ways to cure the related diseases. In the present study, blood flow around a leaflet valve of a perforating vein is investigated numerically by Finite Element Method. Flow behavior and vortexes, generated around the leaflet valves, are studied considering valve opening percentage. Obtained velocity and pressure fields show mechanical stresses on vein wall and these valves and consequently introduce the regions susceptible to deformation.

Keywords: fluid flow, leaflet valve, numerical investigation, perforating vein

Procedia PDF Downloads 383
4727 Theoretical Analysis of Performance Parameters of a Microchannel Heat Exchanger

Authors: Shreyas Kotian, Nishant Jainm, Nachiket Methekar

Abstract:

The increase in energy demands in various industrial sectors has called for devices small in size with high heat transfer rates. Microchannel heat exchangers (MCHX) have thus been studied and applied in various fields such as thermal engineering, aerospace engineering and nanoscale heat transfer. They have been a case of investigation due to their augmented thermal characteristics and low-pressure drop. The goal of the current investigation is to analyze the thermohydraulic performance of the heat exchanger analytically. Studies are done for various inlet conditions and flow conditions. At Thi of 90°C, the effectiveness increased by about 22% for an increase in Re from 1000 to 5000 of the cold fluid. It was also observed that at Re = 5000 for the hot fluid, the heat recovered by the hot fluid increases by about 69% for an increase in inlet temperature of the hot fluid from 50°C to 70°C.

Keywords: theoretical analysis, performance parameters, microchannel heat exchanger, Reynolds number

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4726 Numerical Investigation on Anchored Sheet Pile Quay Wall with Separated Relieving Platform

Authors: Mahmoud Roushdy, Mohamed El Naggar, Ahmed Yehia Abdelaziz

Abstract:

Anchored sheet pile has been used worldwide as front quay walls for decades. With the increase in vessel drafts and weights, those sheet pile walls need to be upgraded by increasing the depth of the dredging line in front of the wall. A system has recently been used to increase the depth in front of the wall by installing a separated platform supported on a deep foundation (so called Relieving Platform) behind the sheet pile wall. The platform is structurally separated from the front wall. This paper presents a numerical investigation utilizing finite element analysis on the behavior of separated relieve platforms installed within existing anchored sheet pile quay walls. The investigation was done in two steps: a verification step followed by a parametric study. In the verification step, the numerical model was verified based on field measurements performed by others. The validated model was extended within the parametric study to a series of models with different backfill soils, separation gap width, and number of pile rows supporting the platform. The results of the numerical investigation show that using stiff clay as backfill soil (neglecting consolidation) gives better performance for the front wall and the first pile row adjacent to sandy backfills. The degree of compaction of the sandy backfill slightly increases lateral deformations but reduces bending moment acting on pile rows, while the effect is minor on the front wall. In addition, the increase in the separation gap width gradually increases bending moments on the front wall regardless of the backfill soil type, while this effect is reversed on pile rows (gradually decrease). Finally, the paper studies the possibility of reducing the number of pile rows along with the separation to take advantage of the positive separation effect on piles.

Keywords: anchored sheet pile, relieving platform, separation gap, upgrade quay wall

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4725 Police and Crime Scene Management Model

Authors: Najaf Hamadzadeh Arbabi

Abstract:

Crime scene management is the first and most critical step in criminal investigations and all the criminal investigations are based on the ability of the crime scene investigation officers for diagnosing the importance and the role of physical evidence at the crime scene. According to the role of available physical evidence at the scene to prove the crime and identify the perpetrator and prove the innocence of those accused have been unduly and also impossible due to the rejection of these reasons, the maintenance and investigation of crime scene and collect evidence are very important in the crime scene. This research, by identifying the factors affecting the management of the crime scene, looking for presenting the effective and efficient indigenous pattern for managing of the crime scene in Iran. Method: This study is an applied and development research. Wilcoxon signed-rank test and the Friedman test for ranking, were used for analyzing the data and all hypotheses were tested at 95% confidence level. The target population is 50 judges and experts in Tehran.

Keywords: crime scene, identification, designation, individualization, reconstruction

Procedia PDF Downloads 248
4724 Investigation of the Effect of Pressure Changes on the Gas Proportional Detector

Authors: S. M. Golgoun, S. M. Taheri

Abstract:

Investigation of radioactive contamination of personnel working in radiation centers to identify radioactive materials and then measure the potential contamination and eliminate it has always been considered. For this purpose, various ways have been proposed so far and different devices have been designed and built. Gas sealed proportional counter has special working conditions. In this research, a gas sealed detector of proportional counter type was made and then its various parameters were investigated. Some parameters are influential on their working conditions and one of these most important parameters is the internal pressure of the proportional gas-filled detector. In this experimental research, we produced software for examination and altering high voltage, registering data, and calculating efficiency. By this, we investigated different gas pressure effects on detector efficiency and proposed optimizing working conditions of this detector. After reviewing the results, we suggested a range between 20-30 mbar pressure for this gas sealed detector.

Keywords: gas sealed, proportional detector, pressure, counter

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4723 Validation of a Fluid-Structure Interaction Model of an Aortic Dissection versus a Bench Top Model

Authors: K. Khanafer

Abstract:

The aim of this investigation was to validate the fluid-structure interaction (FSI) model of type B aortic dissection with our experimental results from a bench-top-model. Another objective was to study the relationship between the size of a septectomy that increases the outflow of the false lumen and its effect on the values of the differential of pressure between true lumen and false lumen. FSI analysis based on Galerkin’s formulation was used in this investigation to study flow pattern and hemodynamics within a flexible type B aortic dissection model using boundary conditions from our experimental data. The numerical results of our model were verified against the experimental data for various tear size and location. Thus, CFD tools have a potential role in evaluating different scenarios and aortic dissection configurations.

Keywords: aortic dissection, fluid-structure interaction, in vitro model, numerical

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4722 Experimental Investigation of On-Body Channel Modelling at 2.45 GHz

Authors: Hasliza A. Rahim, Fareq Malek, Nur A. M. Affendi, Azuwa Ali, Norshafinash Saudin, Latifah Mohamed

Abstract:

This paper presents the experimental investigation of on-body channel fading at 2.45 GHz considering two effects of the user body movement; stationary and mobile. A pair of body-worn antennas was utilized in this measurement campaign. A statistical analysis was performed by comparing the measured on-body path loss to five well-known distributions; lognormal, normal, Nakagami, Weibull and Rayleigh. The results showed that the average path loss of moving arm varied higher than the path loss in sitting position for upper-arm-to-left-chest link, up to 3.5 dB. The analysis also concluded that the Nakagami distribution provided the best fit for most of on-body static link path loss in standing still and sitting position, while the arm movement can be best described by log-normal distribution.

Keywords: on-body channel communications, fading characteristics, statistical model, body movement

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4721 Uncommon Causes of Acute Abdominal Pain: A Pictorial Essay

Authors: Mahesh Hariharan, Rajan Balasubramaniam, Sharath Kumar Shetty, Shanthala Yadavalli, Mohammed Ahetasham, Sravya Devarapalli

Abstract:

Acute abdomen is one of the most common clinical conditions requiring a radiological investigation. Ultrasound is the primary modality of choice which can diagnose some of the common causes of acute abdomen. However, sometimes the underlying cause for the pain is far more complicated than expected to mandate a high degree of suspicion to suggest further investigation with contrast-enhanced computed tomography or magnetic resonance imaging. Here, we have compiled a comprehensive series of selected cases to highlight the conditions which can be easily overlooked unless carefully sought for. This also emphasizes the importance of multimodality approach to arrive at the final diagnosis with an increased overall diagnostic accuracy which in turn improves patient management and prognosis.

Keywords: acute abdomen, contrast-enhanced computed tomography scan, magnetic resonance imaging, plain radiographs, ultrasound

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4720 Failure Pressure Prediction of a Corroded Pipeline Using a Finite Element Method

Authors: Lounes Aouane, Omar Bouledroua

Abstract:

Sonatrach uses 24,000 kilometers of pipelines to transport gas and oil. Over time, these pipes run the risk of bursting due to corrosion inside and/or outside the pipeline. For this reason, a check must be made with the help of an equipped scraper. This intelligent tool provides a detailed picture of all errors in the pipeline. Based on the ERF values, these wear defects are divided into two parts: acceptable defect and unacceptable defect. The objective of this work is to conduct a comparative study of the different methods of calculating the marginal pressure found in the literature (DNV RP F-101, SHELL, P-CORRC, NETTO and CSA Z662). This comparison will be made from a database of 329 burst tests published in the literature. Finally, we will propose a new approach based on the finite element method using the commercial software ANSYS.

Keywords: hydrogen embrittlement, pipelines, hydrogen, transient flow, cyclic pressure, fatigue crack growth

Procedia PDF Downloads 42
4719 The Use of Ontology Framework for Automation Digital Forensics Investigation

Authors: Ahmad Luthfi

Abstract:

One of the main goals of a computer forensic analyst is to determine the cause and effect of the acquisition of a digital evidence in order to obtain relevant information on the case is being handled. In order to get fast and accurate results, this paper will discuss the approach known as ontology framework. This model uses a structured hierarchy of layers that create connectivity between the variant and searching investigation of activity that a computer forensic analysis activities can be carried out automatically. There are two main layers are used, namely analysis tools and operating system. By using the concept of ontology, the second layer is automatically designed to help investigator to perform the acquisition of digital evidence. The methodology of automation approach of this research is by utilizing forward chaining where the system will perform a search against investigative steps and atomically structured in accordance with the rules of the ontology.

Keywords: ontology, framework, automation, forensics

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4718 Forensic Investigation Into the Variation of Geological Properties of Soils Bintulu, Sarawak

Authors: Jaithish John

Abstract:

In this paper a brief overview is provided of the developments in interdisciplinary knowledge exchange with use of soil and geological (earth) materials in the search for evidence. The aim is to provide background information on the role and value of understanding ‘earth materials’ from the crime scene through to microscopic scale investigations to support law enforcement agencies in solving criminal and environmental concerns and investigations. This involves the sampling, analysis, interpretation and explanation presentation of all these evidences. In this context, field and laboratory methods are highlighted for the controlled / referenced sample, alibi sample and questioned sample. The aim of forensic analyses of earth materials is to associate these samples taken from a questioned source to determine if there are similar and outstanding characteristics features of earth materials crucial to support the investigation to the questioned earth materials and compare it to the controlled / referenced sample and alibi samples.

Keywords: soil, texture, grain, microscopy

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4717 Sustainable Underground Structures Through Soil-Driven Bio-Protection of Concrete

Authors: Abdurahim Abogdera, Omar Hamza, David Elliott

Abstract:

The soil bacteria can be affected by some factors such as pH, calcium ions and Electrical conductivity. Fresh concrete has high pH value, which is between 11 and 13 and these values will be prevented the bacteria to produce CO₂ to participate with Calcium ions that released from the concrete to get calcite. In this study we replaced 15% and 25% of cement with Fly ash as the fly ash reduce the value of the pH at the concrete. The main goal of this study was investigated whether bacteria can be used on the soil rather than in the concrete to avoid the challenges and limitations of containing bacteria inside the concrete. This was achieved by incubating cracked cement mortar specimens into fully saturated sterilized and non-sterilized soil. The crack sealing developed in the specimens during the incubation period in both soil conditions were evaluated and compared. Visual inspection, water absorption test, scanning electron microscopy (SEM), and Energy Dispersive X-ray (EDX) were conducted to evaluate the healing process.

Keywords: pH, calcium ions, MICP, salinity

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4716 Analysis of Cracked Beams with Spalling Having Different Arrangements of the Reinforcement Bars Using Finite Element Analysis (FEA)

Authors: Rishabh Shukla, Achin Agrawal, Anupam Saxena, S. Mandal

Abstract:

The existence of a crack, affects the mechanical behaviour and various properties of a structure to a great degree. This paper focuses on recognizing the parameters that gets changed due to the formation of cracks and have a great impact on the performance of the structure. Spalling is a major concern as it leaves the reinforcement bars more susceptible to environmental attacks. Beams of cross section 300 mm × 500 mm are designed and for a calculated area of steel, two different arrangements of reinforced bars are analysed. Results are prepared for different stages of cracking for each arrangement of rebars. The parameters for both arrangements are then compared. The Finite Element Analysis (FEA) is carried out and changes in the properties like flexural strength, Elasticity and modal frequency are reported. The conclusions have been drawn by comparing the results.

Keywords: cracks, elasticity, spalling, FEA

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4715 Non-Homogeneous Layered Fiber Reinforced Concrete

Authors: Vitalijs Lusis, Andrejs Krasnikovs

Abstract:

Fiber reinforced concrete is important material for load bearing structural elements. Usually fibers are homogeneously distributed in a concrete body having arbitrary spatial orientations. At the same time, in many situations, fiber concrete with oriented fibers is more optimal. Is obvious, that is possible to create constructions with oriented short fibers in them, in different ways. Present research is devoted to one of such approaches- fiber reinforced concrete prisms having dimensions 100 mm×100 mm×400 mm with layers of non-homogeneously distributed fibers inside them were fabricated. Simultaneously prisms with homogeneously dispersed fibers were produced for reference as well. Prisms were tested under four point bending conditions. During the tests vertical deflection at the center of every prism and crack opening were measured (using linear displacements transducers in real timescale). Prediction results were discussed.

Keywords: fiber reinforced concrete, 4-point bending, steel fiber, construction engineering

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4714 Prediction of Unsaturated Permeability Functions for Clayey Soil

Authors: F. Louati, H. Trabelsi, M. Jamei

Abstract:

Desiccation cracks following drainage-humidification cycles. With water loss, mainly due to evaporation, suction in the soil increases, producing volumetric shrinkage and tensile stress. When the tensile stress reaches tensile strength, the soil cracks. Desiccation cracks networks can directly control soil hydraulic properties. The aim of this study was for quantifying the hydraulic properties for examples the water retention curve, the saturated hydraulic conductivity, the unsaturated hydraulic conductivity function, the shrinkage dynamics in Tibar soil- clay soil in the Northern of Tunisia. Then a numerical simulation of unsaturated hydraulic properties for a crack network has been attempted. The finite elements code ‘CODE_BRIGHT’ can be used to follow the hydraulic distribution in cracked porous media.

Keywords: desiccation, cracks, permeability, unsaturated hydraulic flow, simulation

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4713 Ultrasonic Pulse Velocity Investigation of Polypropylene and Steel Fiber Reinforced Concrete

Authors: Erjola Reufi, Jozefita Marku, Thomas Bier

Abstract:

Ultrasonic pulse velocity (UPV) method has been shown for some time to provide a reliable means of estimating properties and offers a unique opportunity for direct, quick and safe control of building damaged by earthquake, fatigue, conflagration and catastrophic scenarios. On this investigation hybrid reinforced concrete has been investigated by UPV method. Hooked end steel fiber of length 50 and 30 mm was added to concrete in different proportion 0, 0.25, 0.5, and 1 % by the volume of concrete. On the other hand, polypropylene fiber of length 12, 6, 3 mm was added to concrete of 0.1, 0.2, and 0.4 % by the volume of concrete. Fifteen different mixture has been prepared to investigate the relation between compressive strength and UPV values and also to investigate on the effect of volume and type of fiber on UPV values.

Keywords: compressive strength, polypropylene fiber, steel fiber, ultrasonic pulse velocity, volume, type of fiber

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4712 Experimental Investigation on High Performance Concrete with Silica Fume and Ceramic Waste

Authors: P. Vinayagam, A. Madhanagopal

Abstract:

This experimental investigation focuses on the study of the strength of concrete with ceramic waste as coarse aggregate. It is not a new concept of using alternate materials for aggregates. Pottery and ceramics have been an important part of human culture for thousands of years. The ceramic waste from ceramic and construction industries is a major contribution to construction demolition waste (CDW), representing a serious environmental, technical, and economical problem of today’s society. The major sources of ceramic waste are ceramic industry, building construction and building demolition. In ceramic industries, a significant part of the losses in the manufacturing of ceramic elements is not returned to the production process. In building construction, ceramic waste is produced during transportation to the building site, on the execution of several construction elements and on subsequent works. This waste is regionally deposited in dumping grounds, without any separation or reuse. In this study an attempt has been made to find the suitability of the ceramic industrial wastes as a possible replacement for conventional crushed stone coarse aggregate in high performance concrete. In this study, glazed stoneware pipe waste was used as coarse aggregates. In this investigation, physical properties of ceramic waste coarse aggregates were studied. Experiments were carried out to determine the strength of high performance concrete with silica fume and ceramic stoneware pipe waste coarse aggregate of 10%, 20%, 30%, 40% and 50% different replacement ratios in comparison with those of corresponding conventional concrete mixes.

Keywords: ceramic waste, coarse aggregate replacement, glazed stoneware pipe waste, silica fume

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4711 Design and Manufacture of Non-Contact Moving Load for Experimental Analysis of Beams

Authors: Firooz Bakhtiari-Nejad, Hamidreza Rostami, Meysam Mirzaee, Mona Zandbaf

Abstract:

Dynamic tests are an important step of the design of engineering structures, because the accuracy of predictions of theoretical–numerical procedures can be assessed. In experimental test of moving loads that is one of the major research topics, the load is modeled as a simple moving mass or a small vehicle. This paper deals with the applicability of Non-Contact Moving Load (NML) for vibration analysis. For this purpose, an experimental set-up is designed to generate the different types of NML including constant and harmonic. The proposed method relies on pressurized air which is useful, especially when dealing with fragile or sensitive structures. To demonstrate the performance of this system, the set-up is employed for a modal analysis of a beam and detecting crack of the beam. The obtained results indicate that the experimental set-up for NML can be an attractive alternative to the moving load problems.

Keywords: experimental analysis, moving load, non-contact excitation, materials engineering

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4710 Characterization of Ultrasonic Nonlinearity in Concrete under Cyclic Change of Prestressing Force

Authors: Gyu-Jin Kim, Hyo-Gyoung Kwak

Abstract:

In this research, the effect of prestressing force on the nonlinearity of concrete was investigated by an experimental study. For the measurement of ultrasonic nonlinearity, a prestressed concrete beam was prepared and a nonlinear resonant ultrasound method was adopted. When the prestressing force changes, the stress state of the concrete inside the beam is affected, which leads to the occurrence of micro-cracks and changes in mechanical properties. Therefore, it is necessary to introduce nonlinear ultrasonic technology which sensitively reflects microstructural changes. Repetitive prestressing load history, including maximum levels of 45%, 60% and 75%, depending on the compressive strength, is designed to evaluate the impact of loading levels on the nonlinearity. With the experimental results, the possibility of ultrasonic nonlinearity as a trial indicator of stress was evaluated.

Keywords: micro crack, nonlinear ultrasonic resonant spectroscopy, prestressed concrete beam, prestressing force, ultrasonic nonlinearity

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4709 Numerical Simulation of Fiber Bragg Grating Spectrum for Mode-І Delamination Detection

Authors: O. Hassoon, M. Tarfoui, A. El Malk

Abstract:

Fiber Bragg optic sensor embedded in composite material to detect and monitor the damage which is occur in composite structure. In this paper we deal with the mode-Ι delamination to determine the resistance of material to crack propagation, and use the coupling mode theory and T-matrix method to simulating the FBGs spectrum for both uniform and non-uniform strain distribution. The double cantilever beam test which is modeling in FEM to determine the Longitudinal strain, there are two models which are used, the first is the global half model, and the second the sub-model to represent the FBGs with refine mesh. This method can simulate the damage in the composite structure and converting the strain to wavelength shifting of the FBG spectrum.

Keywords: fiber bragg grating, delamination detection, DCB, FBG spectrum, structure health monitoring

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4708 Earthquake Hazards in Manipur: Casual Factors and Remedial Measures

Authors: Kangujam Monika, Kiranbala Devi Thokchom, Soibam Sandhyarani Devi

Abstract:

Earthquake is a major natural hazard in India. Manipur, located in the North-Eastern Region of India, is one of the most affected location in the region prone to earthquakes since it lies in an area where Indian and Eurasian tectonic plates meet and is in seismic Zone V which is the most severe intensity zone, according to IS Code. Some recent earthquakes recorded in Manipur are M 6.7 epicenter at Tamenglong (January 4, 2016), M 5.2 epicenter at Churachandpur (February 24, 2017) and most recent M 4.4 epicenter at Thoubal (June 19, 2017). In these recent earthquakes, some houses and buildings were damaged, landslides were also occurred. A field study was carried out. An overview of the various causal factors involved in triggering of earthquake in Manipur has been discussed. It is found that improper planning, poor design, negligence, structural irregularities, poor quality materials, construction of foundation without proper site soil investigation and non-implementation of remedial measures, etc., are possibly the main causal factors for damage in Manipur during earthquake. The study also suggests, though the proper design of structure and foundation along with soil investigation, ground improvement methods, use of modern techniques of construction, counseling with engineer, mass awareness, etc., might be effective solution to control the hazard in many locations. An overview on the analysis pertaining to earthquake in Manipur together with on-going detailed site specific geotechnical investigation were presented.

Keywords: Manipur, earthquake, hazard, structure, soil

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4707 Laser Ultrasonic Diagnostics and Acoustic Emission Technique for Examination of Rock Specimens under Uniaxial Compression

Authors: Elena B. Cherepetskaya, Vladimir A. Makarov, Dmitry V. Morozov, Ivan E. Sas

Abstract:

Laboratory studies of the stress-strain behavior of rocks specimens were conducted by using acoustic emission and laser-ultrasonic diagnostics. The sensitivity of the techniques allowed changes in the internal structure of the specimens under uniaxial compressive load to be examined at micro- and macro scales. It was shown that microcracks appear in geologic materials when the stress level reaches about 50% of breaking strength. Also, the characteristic stress of the main crack formation was registered in the process of single-stage compression of rocks. On the base of laser-ultrasonic echoscopy, 2D visualization of the internal structure of rocky soil specimens was realized, and the microcracks arising during uniaxial compression were registered.

Keywords: acoustic emission, geomaterial, laser ultrasound, uniaxial compression

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4706 Regional Trade Integration: Empirical Investigation of Trade within the European Union versus Association for South East Asian Nations

Authors: Sarina Zainab Shirazi

Abstract:

Abstract— With the advent of globalization, different countries have liberalized their trade policies to enhance economic integration and developmental processes but the advantages accrued vary greatly from region to region. This study specifically examines European Union (EU) and Association for South East Asian Nations (ASEAN), two regions that show contrasting integration patterns. EU shows most successful integrations versus the slower paced integration in the ASEAN region. A comprehensive panel data empirical investigation of EU and ASEAN in the context of economy size, geographical distances, language, ethnicity, common border and regional trade agreements (RTA) is conducted for a period of 1985 – 2015. The empirical investigation through the augmented gravity equation shows that the real effectiveness for enhanced intra-regional trade is significant when specific examination of export and import components is conducted in the presence of non-tariff barriers. These barriers surface in the form of terms of trade openness, inflation, exchange rate, common borders, common language, ethnic similarity, and presence of a formal regional trade agreement (RTA). Thus, these factors can be utilized by the EU and ASEAN regions in order to formulate effective policy tools to enhance trade within their respective spheres of influence.

Keywords: Association for South East Asian Nations, European Union, Gravity Model, Regional Trade

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