Search results for: Direct Instructional Technique
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9987

Search results for: Direct Instructional Technique

7827 Prediction of Compressive Strength of Concrete from Early Age Test Result Using Design of Experiments (Rsm)

Authors: Salem Alsanusi, Loubna Bentaher

Abstract:

Response Surface Methods (RSM) provide statistically validated predictive models that can then be manipulated for finding optimal process configurations. Variation transmitted to responses from poorly controlled process factors can be accounted for by the mathematical technique of propagation of error (POE), which facilitates ‘finding the flats’ on the surfaces generated by RSM. The dual response approach to RSM captures the standard deviation of the output as well as the average. It accounts for unknown sources of variation. Dual response plus propagation of error (POE) provides a more useful model of overall response variation. In our case, we implemented this technique in predicting compressive strength of concrete of 28 days in age. Since 28 days is quite time consuming, while it is important to ensure the quality control process. This paper investigates the potential of using design of experiments (DOE-RSM) to predict the compressive strength of concrete at 28th day. Data used for this study was carried out from experiment schemes at university of Benghazi, civil engineering department. A total of 114 sets of data were implemented. ACI mix design method was utilized for the mix design. No admixtures were used, only the main concrete mix constituents such as cement, coarse-aggregate, fine aggregate and water were utilized in all mixes. Different mix proportions of the ingredients and different water cement ratio were used. The proposed mathematical models are capable of predicting the required concrete compressive strength of concrete from early ages.

Keywords: mix proportioning, response surface methodology, compressive strength, optimal design

Procedia PDF Downloads 267
7826 The Curvature of Bending Analysis and Motion of Soft Robotic Fingers by Full 3D Printing with MC-Cells Technique for Hand Rehabilitation

Authors: Chaiyawat Musikapan, Ratchatin Chancharoen, Saknan Bongsebandhu-Phubhakdi

Abstract:

For many recent years, soft robotic fingers were used for supporting the patients who had survived the neurological diseases that resulted in muscular disorders and neural network damages, such as stroke and Parkinson’s disease, and inflammatory symptoms such as De Quervain and trigger finger. Generally, the major hand function is significant to manipulate objects in activities of daily living (ADL). In this work, we proposed the model of soft actuator that manufactured by full 3D printing without the molding process and one material for use. Furthermore, we designed the model with a technique of multi cavitation cells (MC-Cells). Then, we demonstrated the curvature bending, fluidic pressure and force that generated to the model for assistive finger flexor and hand grasping. Also, the soft actuators were characterized in mathematics solving by the length of chord and arc length. In addition, we used an adaptive push-button switch machine to measure the force in our experiment. Consequently, we evaluated biomechanics efficiency by the range of motion (ROM) that affected to metacarpophalangeal joint (MCP), proximal interphalangeal joint (PIP) and distal interphalangeal joint (DIP). Finally, the model achieved to exhibit the corresponding fluidic pressure with force and ROM to assist the finger flexor and hand grasping.

Keywords: biomechanics efficiency, curvature bending, hand functional assistance, multi cavitation cells (MC-Cells), range of motion (ROM)

Procedia PDF Downloads 260
7825 Ranking of Provinces in Iran for Capital Formation in Spatial Planning with Numerical Taxonomy Technique (An Improvement) Case Study: Agriculture Sector

Authors: Farhad Nouparast

Abstract:

For more production we need more capital formation. Capital formation in each country should be based on comparative advantages in different economic sectors due to the different production possibility curves. In regional planning, recognizing the relative advantages and consequently investing in more production requires identifying areas with the necessary capabilities and location of each region compared to other regions. In this article, ranking of Iran's provinces is done according to the specific and given variables as the best investment position in agricultural activity. So we can provide the necessary background for investment analysis in different regions of the country to formulate national and regional planning and execute investment projects. It is used factor analysis technique and numerical taxonomy analysis to do this in thisarticle. At first, the provinces are homogenized and graded according to the variables using cross-sectional data obtained from the agricultural census and population and housing census of Iran as data matrix. The results show that which provinces have the most potential for capital formation in agronomy sub-sector. Taxonomy classifies organisms based on similar genetic traits in biology and botany. Numerical taxonomy using quantitative methods controls large amounts of information and get the number of samples and categories and take them based on inherent characteristics and differences indirectly accommodates. Numerical taxonomy is related to multivariate statistics.

Keywords: Capital Formation, Factor Analysis, Multivariate statistics, Numerical Taxonomy Analysis, Production, Ranking, Spatial Planning

Procedia PDF Downloads 140
7824 Review of Theories and Applications of Genetic Programing in Sediment Yield Modeling

Authors: Adesoji Tunbosun Jaiyeola, Josiah Adeyemo

Abstract:

Sediment yield can be considered to be the total sediment load that leaves a drainage basin. The knowledge of the quantity of sediments present in a river at a particular time can lead to better flood capacity in reservoirs and consequently help to control over-bane flooding. Furthermore, as sediment accumulates in the reservoir, it gradually loses its ability to store water for the purposes for which it was built. The development of hydrological models to forecast the quantity of sediment present in a reservoir helps planners and managers of water resources systems, to understand the system better in terms of its problems and alternative ways to address them. The application of artificial intelligence models and technique to such real-life situations have proven to be an effective approach of solving complex problems. This paper makes an extensive review of literature relevant to the theories and applications of evolutionary algorithms, and most especially genetic programming. The successful applications of genetic programming as a soft computing technique were reviewed in sediment modelling and other branches of knowledge. Some fundamental issues such as benchmark, generalization ability, bloat and over-fitting and other open issues relating to the working principles of GP, which needs to be addressed by the GP community were also highlighted. This review aim to give GP theoreticians, researchers and the general community of GP enough research direction, valuable guide and also keep all stakeholders abreast of the issues which need attention during the next decade for the advancement of GP.

Keywords: benchmark, bloat, generalization, genetic programming, over-fitting, sediment yield

Procedia PDF Downloads 446
7823 Thermoluminescent Response of Nanocrystalline BaSO4:Eu to 85 MeV Carbon Beams

Authors: Shaila Bahl, S. P. Lochab, Pratik Kumar

Abstract:

Nanotechnology and nanomaterials have attracted researchers from different fields, especially from the field of luminescence. Recent studies on various luminescent nanomaterials have shown their relevance in dosimetry of ionizing radiations for the measurements of high doses using the Thermoluminescence (TL) technique, where the conventional microcrystalline phosphors saturate. Ion beams have been used for diagnostic and therapeutic purposes due to their favorable profile of dose deposition at the end of the range known as the Bragg peak. While dealing with human beings, doses from these beams need to be measured with great precision and accuracy. Henceforth detailed investigations of suitable thermoluminescent dosimeters (TLD) for dose verification in ion beam irradiation are required. This paper investigates the TL response of nanocrystalline BaSO4 doped with Eu to 85 MeV carbon beam. The synthesis was done using Co-precipitation technique by mixing Barium chloride and ammonium sulphate solutions. To investigate the crystallinity and particle size, analytical techniques such as X-ray diffraction (XRD) and Transmission electron microscopy (TEM) were used which revealed the average particle sizes to 45 nm with orthorhombic structure. Samples in pellet form were irradiated by 85 MeV carbon beam in the fluence range of 1X1010-5X1013. TL glow curves of the irradiated samples show two prominent glow peaks at around 460 K and 495 K. The TL response is linear up to 1X1013 fluence after which saturation was observed. The wider linear TL response of nanocrystalline BaSO4: Eu and low fading make it a superior candidate as a dosimeter to be used for detecting the doses of carbon beam.

Keywords: radiation, dosimetry, carbon ions, thermoluminescence

Procedia PDF Downloads 289
7822 Novel Inference Algorithm for Gaussian Process Classification Model with Multiclass and Its Application to Human Action Classification

Authors: Wanhyun Cho, Soonja Kang, Sangkyoon Kim, Soonyoung Park

Abstract:

In this paper, we propose a novel inference algorithm for the multi-class Gaussian process classification model that can be used in the field of human behavior recognition. This algorithm can drive simultaneously both a posterior distribution of a latent function and estimators of hyper-parameters in a Gaussian process classification model with multi-class. Our algorithm is based on the Laplace approximation (LA) technique and variational EM framework. This is performed in two steps: called expectation and maximization steps. First, in the expectation step, using the Bayesian formula and LA technique, we derive approximately the posterior distribution of the latent function indicating the possibility that each observation belongs to a certain class in the Gaussian process classification model. Second, in the maximization step, using a derived posterior distribution of latent function, we compute the maximum likelihood estimator for hyper-parameters of a covariance matrix necessary to define prior distribution for latent function. These two steps iteratively repeat until a convergence condition satisfies. Moreover, we apply the proposed algorithm with human action classification problem using a public database, namely, the KTH human action data set. Experimental results reveal that the proposed algorithm shows good performance on this data set.

Keywords: bayesian rule, gaussian process classification model with multiclass, gaussian process prior, human action classification, laplace approximation, variational EM algorithm

Procedia PDF Downloads 334
7821 The Employment Experiences of Qualified Refugees in the UK and the Impact on Identity, Integration, and Wellbeing: A Qualitative Enquiry

Authors: Amina El-Warari, Agata Vitale, Laura Caulfield, Jennifer Kinloch

Abstract:

Background: Unemployment levels among refugees in the UK are much higher than voluntary migrants and UK-born citizens. The lack of employment and/or of suitable employment has detrimental consequences on refugees’ ability to integrate and become active citizens in the host country. Research indicates that, when individuals are forced to migrate, one of the most significant aspects to building their identity is their previous profession; this particularly applies to qualified refugees. Despite this, there is little support available to them. The current study is set in this context and aims to explore highly qualified refugees’ employment-related experiences in the UK as well as their suggestions on how to develop specific interventions that can support them in finding suitable employment. Methods: A qualitative study design was employed. Qualitative methods are in fact well suited to research with refugees, as they allow them to give their direct opinion, rather than this being filtered by stakeholders. Listening to ‘the refugee’s voice’ means developing ‘a refugee centered perspective’ where the diverse narratives told by participants are organized to tell their direct collective story. A total of 12 refugees, attending a non-profit refugee organization in the south-west of England, took part in the study. The selection criteria were being over 18, having a level of English that allows them to sustain a conversation, and having a University degree and/or professional qualification. All participants were interviewed individually; the data were transcribed and analyzed thematically. Findings: Participants had very little support in finding suitable employment; this often only consisted of a few sessions in their local job centers and English tutorials. They indicated that being unemployed/underemployed negatively affected their sense of identity, their acculturative stress, and their in-group/ out-group relations. They suggested that specific employment interventions for qualified refugees should be delivered to them individually in order to address their specific needs. Furthermore, most participants suggested that these interventions should support them in volunteering in organizations that match their skills/ qualifications. They also indicated that the employment interventions should support them in having their qualifications recognized in the UK as well as building links with universities/ centers where they can receive adequate training on how to understand and adapt to the employments needs in the UK. Conclusions: These findings will provide the basis for the second stage of the research where specific employment interventions will be designed and tested with highly qualified refugees. In addition, these findings shed light refugee integration policy.

Keywords: employment interventions, identity, integration, qualified refugees

Procedia PDF Downloads 264
7820 Comparison of the Effects of Continuous Flow Microwave Pre-Treatment with Different Intensities on the Anaerobic Digestion of Sewage Sludge for Sustainable Energy Recovery from Sewage Treatment Plant

Authors: D. Hephzibah, P. Kumaran, N. M. Saifuddin

Abstract:

Anaerobic digestion is a well-known technique for sustainable energy recovery from sewage sludge. However, sewage sludge digestion is restricted due to certain factors. Pre-treatment methods have been established in various publications as a promising technique to improve the digestibility of the sewage sludge and to enhance the biogas generated which can be used for energy recovery. In this study, continuous flow microwave (MW) pre-treatment with different intensities were compared by using 5 L semi-continuous digesters at a hydraulic retention time of 27 days. We focused on the effects of MW at different intensities on the sludge solubilization, sludge digestibility, and biogas production of the untreated and MW pre-treated sludge. The MW pre-treatment demonstrated an increase in the ratio of soluble chemical oxygen demand to total chemical oxygen demand (sCOD/tCOD) and volatile fatty acid (VFA) concentration. Besides that, the total volatile solid (TVS) removal efficiency and tCOD removal efficiency also increased during the digestion of the MW pre-treated sewage sludge compared to the untreated sewage sludge. Furthermore, the biogas yield also subsequently increases due to the pre-treatment effect. A higher MW power level and irradiation time generally enhanced the biogas generation which has potential for sustainable energy recovery from sewage treatment plant. However, the net energy balance tabulation shows that the MW pre-treatment leads to negative net energy production.

Keywords: anaerobic digestion, biogas, microwave pre-treatment, sewage sludge

Procedia PDF Downloads 319
7819 Production of Biogas

Authors: J. O. Alabi

Abstract:

Biogas is a clean burning, easily produced natural fuel that is an important source of energy for cooking and heating in rural areas and third world countries. Anaerobic bacteria inside biodigesters break down biomass to produce biogas. (Which is 70% methane)? Currently there is no simple way to compress and store biogas. So, in order to use biogas as a source of energy, a direct feed from biodigeser to the store tap or heater must be made. Any excess biogas is vented into the atmosphere, which is wasteful and car have a negative effect on the environment, we have been tasked with designing a system that will be able to compress biogas using an off-grid power supply, making the biogas portable and makes through the use of large-scale, shared biodigester. Our final design is a system that maximizes simplicity and safety while minimizing cost.

Keywords: biogas, biodigesters, natural fuel, bionanotechnology

Procedia PDF Downloads 364
7818 Maximum Distance Separable b-Symbol Repeated-Root γ-Constacylic Codes over a Finite Chain Ring of Length 2

Authors: Jamal Laaouine, Mohammed Elhassani Charkani

Abstract:

Let p be a prime and let b be an integer. MDS b-symbol codes are a direct generalization of MDS codes. The γ-constacyclic codes of length pˢ over the finite commutative chain ring Fₚm [u]/ < u² > had been classified into four distinct types, where is a nonzero element of the field Fₚm. Let C₃ be a code of Type 3. In this paper, we obtain the b-symbol distance db(C₃) of the code C₃. Using this result, necessary and sufficient conditions under which C₃ is an MDS b-symbol code are given.

Keywords: constacyclic code, repeated-root code, maximum distance separable, MDS codes, b-symbol distance, finite chain rings

Procedia PDF Downloads 137
7817 Teachers’ Experiences regarding Use of Information and Communication Technology for Visually Impaired Students

Authors: Zikra Faiz, Zaheer Asghar, Nisar Abid

Abstract:

Information and Communication Technologies (ICTs) includes computers, the Internet, and electronic delivery systems such as televisions, radios, multimedia, and overhead projectors etc. In the modern world, ICTs is considered as an essential element of the teaching-learning process. The study was aimed to discover the usage of ICTs in Special Education Institutions for Visually Impaired students, Lahore, Pakistan. Objectives of the study were to explore the problems faced by teachers while using ICT in the classroom. The study was phenomenology in nature; a qualitative survey method was used through a semi-structured interview protocol developed by the researchers. The sample comprised of eighty faculty members selected through a purposive sampling technique. Data were analyzed through thematic analysis technique with the help of open coding. The study findings revealed that multimedia, projectors, computers, laptops and LEDs are used in special education institutes to enhance the teaching-learning process. Teachers believed that ICTs could enhance the knowledge of visually impaired students and every student should use these technologies in the classroom. It was concluded that multimedia, projectors and laptops are used in classroom by teachers and students. ICTs can promote effectively through the training of teachers and students. It was suggested that the government should take steps to enhance ICTs in teacher training and other institutions by pre-service and in-service training of teachers.

Keywords: information and communication technologies, in-services teachers, special education institutions

Procedia PDF Downloads 127
7816 The Structure and Development of a Wing Tip Vortex under the Effect of Synthetic Jet Actuation

Authors: Marouen Dghim, Mohsen Ferchichi

Abstract:

The effect of synthetic jet actuation on the roll-up and the development of a wing tip vortex downstream a square-tipped rectangular wing was investigated experimentally using hotwire anemometry. The wing is equipped with a hallow cavity designed to generate a high aspect ratio synthetic jets blowing at an angles with respect to the spanwise direction. The structure of the wing tip vortex under the effect of fluidic actuation was examined at a chord Reynolds number Re_c=8×10^4. An extensive qualitative study on the effect of actuation on the spanwise pressure distribution at c⁄4 was achieved using pressure scanner measurements in order to determine the optimal actuation parameters namely, the blowing momentum coefficient, Cμ, and the non-dimensionalized actuation frequency, F^+. A qualitative study on the effect of actuation parameters on the spanwise pressure distribution showed that optimal actuation frequencies of the synthetic jet were found within the range amplified by both long and short wave instabilities where spanwise pressure coefficients exhibited a considerable decrease by up to 60%. The vortex appeared larger and more diffuse than that of the natural vortex case. Operating the synthetic jet seemed to introduce unsteadiness and turbulence into the vortex core. Based on the ‘a priori’ optimal selected parameters, results of the hotwire wake survey indicated that the actuation achieved a reduction and broadening of the axial velocity deficit. A decrease in the peak tangential velocity associated with an increase in the vortex core radius was reported as a result of the accelerated radial transport of angular momentum. Peak vorticity level near the core was also found to be largely diffused as a direct result of the increased turbulent mixing within the vortex. The wing tip vortex a exhibited a reduced strength and a diffused core as a direct result of increased turbulent mixing due to the presence of turbulent small scale vortices within its core. It is believed that the increased turbulence within the vortex due to the synthetic jet control was the main mechanism associated with the decreased strength and increased size of the wing tip vortex as it evolves downstream. A comparison with a ‘non-optimal’ case was included to demonstrate the effectiveness of selecting the appropriate control parameters. The Synthetic Jet will be operated at various actuation configurations and an extensive parametric study is projected to determine the optimal actuation parameters.

Keywords: flow control, hotwire anemometry, synthetic jet, wing tip vortex

Procedia PDF Downloads 436
7815 Evaluating the Impact of Cloud Computing on Collaboration Service in Knowledge Management Systems

Authors: Hamid Reza Nikkhah, Abbas Toloei Eshlaghi, Hossein Ali Momeni

Abstract:

One of the most important services of Knowledge Management Systems (KMS) is collaboration service which plays a decisive role in organization efficiency. Cloud computing as one of the latest IT technologies has brought a new paradigm in delivering services and communications. In this research, we evaluate the impact of cloud computing on the collaboration service of KMS and for doing so, four variables of cloud computing and three variables of the collaboration service were detected to be assessed.It was found that cloud computing has a far-fetching direct impact on the collaboration service.

Keywords: cloud computing, collaboration service, knowledge management systems, cloud computing

Procedia PDF Downloads 521
7814 The Effect of Substrate Temperature on the Structural, Optical, and Electrical of Nano-Crystalline Tin Doped-Cadmium Telluride Thin Films for Photovoltaic Applications

Authors: Eman A. Alghamdi, A. M. Aldhafiri

Abstract:

It was found that the induce an isolated dopant close to the middle of the bandgap by occupying the Cd position in the CdTe lattice structure is an efficient factor in reducing the nonradiative recombination rate and increasing the solar efficiency. According to our laboratory results, this work has been carried out to obtain the effect of substrate temperature on the CdTe0.6Sn0.4 prepared by thermal evaporation technique for photovoltaic application. Various substrate temperature (25°C, 100°C, 150°C, 200°C, 250°C and 300°C) was applied. Sn-doped CdTe thin films on a glass substrate at a different substrate temperature were made using CdTe and SnTe powders by the thermal evaporation technique. The structural properties of the prepared samples were determined using Raman, x-Ray Diffraction. Spectroscopic ellipsometry and spectrophotometric measurements were conducted to extract the optical constants as a function of substrate temperature. The structural properties of the grown films show hexagonal and cubic mixed structures and phase change has been reported. Scanning electron microscopy (SEM) reviled that a homogenous with a bigger grain size was obtained at 250°C substrate temperature. The conductivity measurements were recorded as a function of substrate temperatures. The open-circuit voltage was improved by controlling the substrate temperature due to the improvement of the fundamental material issues such as recombination and low carrier concentration. All the result was explained and discussed on the biases of the influences of the Sn dopant and the substrate temperature on the structural, optical and photovoltaic characteristics.

Keywords: CdTe, conductivity, photovoltaic, ellipsometry

Procedia PDF Downloads 133
7813 Sequential Pattern Mining from Data of Medical Record with Sequential Pattern Discovery Using Equivalent Classes (SPADE) Algorithm (A Case Study : Bolo Primary Health Care, Bima)

Authors: Rezky Rifaini, Raden Bagus Fajriya Hakim

Abstract:

This research was conducted at the Bolo primary health Care in Bima Regency. The purpose of the research is to find out the association pattern that is formed of medical record database from Bolo Primary health care’s patient. The data used is secondary data from medical records database PHC. Sequential pattern mining technique is the method that used to analysis. Transaction data generated from Patient_ID, Check_Date and diagnosis. Sequential Pattern Discovery Algorithms Using Equivalent Classes (SPADE) is one of the algorithm in sequential pattern mining, this algorithm find frequent sequences of data transaction, using vertical database and sequence join process. Results of the SPADE algorithm is frequent sequences that then used to form a rule. It technique is used to find the association pattern between items combination. Based on association rules sequential analysis with SPADE algorithm for minimum support 0,03 and minimum confidence 0,75 is gotten 3 association sequential pattern based on the sequence of patient_ID, check_Date and diagnosis data in the Bolo PHC.

Keywords: diagnosis, primary health care, medical record, data mining, sequential pattern mining, SPADE algorithm

Procedia PDF Downloads 401
7812 Surface Modification of Polycarbonate Substrates via Direct Fluorination to Promote the Staining with Methylene Blue

Authors: Haruka Kaji, Jae-Ho Kim, Yonezawa Susumu

Abstract:

The surface of polycarbonate (PC) was modified with fluorine gas at 25℃ and 10-380 Torr for one h. The surface roughness of the fluorinated PC samples was approximately five times larger than that (1.2 nm) of the untreated thing. The results of Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy showed that the bonds (e.g., -C=O and C-Hx) derived from raw PC decreased and were converted into fluorinated bonds (e.g., -CFx) after surface fluorination. These fluorinated bonds showed higher electronegativity according to the zeta potential results. Fluorinated PC could be strained with the methylene blue basic dye because of the increased surface roughness and the negatively charged surface.

Keywords: dyeable layer, polycarbonate, surface fluorination, zeta potential

Procedia PDF Downloads 180
7811 Ultrasonic Irradiation Synthesis of High-Performance Pd@Copper Nanowires/MultiWalled Carbon Nanotubes-Chitosan Electrocatalyst by Galvanic Replacement toward Ethanol Oxidation in Alkaline Media

Authors: Majid Farsadrouh Rashti, Amir Shafiee Kisomi, Parisa Jahani

Abstract:

The direct ethanol fuel cells (DEFCs) are contemplated as a promising energy source because, In addition to being used in portable electronic devices, it is also used for electric vehicles. The synthesis of bimetallic nanostructures due to their novel optical, catalytic and electronic characteristic which is precisely in contrast to their monometallic counterparts is attracting extensive attention. Galvanic replacement (sometimes is named to as cementation or immersion plating) is an uncomplicated and effective technique for making nanostructures (such as core-shell) of different metals, semiconductors, and their application in DEFCs. The replacement of galvanic does not need any external power supply compared to electrodeposition. In addition, it is different from electroless deposition because there is no need for a reducing agent to replace galvanizing. In this paper, a fast method for the palladium (Pd) wire nanostructures synthesis with the great surface area through galvanic replacement reaction utilizing copper nanowires (CuNWS) as a template by the assistance of ultrasound under room temperature condition is proposed. To evaluate the morphology and composition of Pd@ Copper nanowires/MultiWalled Carbon nanotubes-Chitosan, emission scanning electron microscopy, energy dispersive X-ray spectroscopy were applied. In order to measure the phase structure of the electrocatalysts were performed via room temperature X-ray powder diffraction (XRD) applying an X-ray diffractometer. Various electrochemical techniques including chronoamperometry and cyclic voltammetry were utilized for the electrocatalytic activity of ethanol electrooxidation and durability in basic solution. Pd@ Copper nanowires/MultiWalled Carbon nanotubes-Chitosan catalyst demonstrated substantially enhanced performance and long-term stability for ethanol electrooxidation in the basic solution in comparison to commercial Pd/C that demonstrated the potential in utilizing Pd@ Copper nanowires/MultiWalled Carbon nanotubes-Chitosan as efficient catalysts towards ethanol oxidation. Noticeably, the Pd@ Copper nanowires/MultiWalled Carbon nanotubes-Chitosan presented excellent catalytic activities with a peak current density of 320.73 mAcm² which was 9.5 times more than in comparison to Pd/C (34.2133 mAcm²). Additionally, activation energy thermodynamic and kinetic evaluations revealed that the Pd@ Copper nanowires/MultiWalled Carbon nanotubes-Chitosan catalyst has lower compared to Pd/C which leads to a lower energy barrier and an excellent charge transfer rate towards ethanol oxidation.

Keywords: core-shell structure, electrocatalyst, ethanol oxidation, galvanic replacement reaction

Procedia PDF Downloads 147
7810 Forest Degradation and Implications for Rural Livelihood in Kaimur Reserve Forest of Bihar, India

Authors: Shashi Bhushan, Sucharita Sen

Abstract:

In India, forest and people are inextricably linked since millions of people live adjacent to or within protected areas and harvest forest products. Indian forest has their own legacy to sustain by its own climatic nature with several social, economic and cultural activities. People surrounding forest areas are not only dependent on this resource for their livelihoods but also for the other source, like religious ceremonies, social customs and herbal medicines, which are determined by the forest like agricultural land, groundwater level, and soil fertility. The assumption that fuelwood and fodder extraction, which is the part of local livelihood leads to deforestation, has so far been the dominant mainstream views in deforestation discourses. Given the occupational division across social groups in Kaimur reserve forest, the differential nature of dependence of forest resources is important to understand. This paper attempts to assess the nature of dependence and impact of forest degradation on rural households across various social groups. Also, an additional element that is added to the enquiry is the way degradation of forests leading to scarcity of forest-based resources impacts the patterns of dependence across various social groups. Change in forest area calculated through land use land cover analysis using remote sensing technique and examination of different economic activities carried out by the households that are forest-based was collected by primary survey in Kaimur reserve forest of state of Bihar in India. The general finding indicates that the Scheduled Tribe and Scheduled Caste communities, the most socially and economically deprived sections of the rural society are involved in a significant way in collection of fuelwood, fodder, and fruits, both for self-consumption and sale in the market while other groups of society uses fuelwood, fruit, and fodder for self-use only. Depending on the local forest resources for fuelwood consumption was the primary need for all social groups due to easy accessibility and lack of alternative energy source. In last four decades, degradation of forest made a direct impact on rural community mediated through the socio-economic structure, resulting in a shift from forest-based occupations to cultivation and manual labour in agricultural and non-agricultural activities. Thus there is a need to review the policies with respect to the ‘community forest management’ since this study clearly throws up the fact that engagement with and dependence on forest resources is socially differentiated. Thus tying the degree of dependence and forest management becomes extremely important from the view of ‘sustainable’ forest resource management. The statization of forest resources also has to keep in view the intrinsic way in which the forest-dependent population interacts with the forest.

Keywords: forest degradation, livelihood, social groups, tribal community

Procedia PDF Downloads 169
7809 Influence of Servant Leadership on Faculty Retention in Higher Education Institutes: Mediating Role of Job Satisfaction

Authors: Aneela Sheikh

Abstract:

Private higher education institutes are challenged for their resilience and competitive edge in the globalized knowledge-based economy in the 21st century. Faculty retention plays an important role as a catalyst for addressing the current mega-developmental phenomenon in higher education institutes faced by developing countries. This study intends to explore the influence of servant leadership practice on faculty retention through the intervening role of job satisfaction towards minimizing the high faculty turnover in private higher education institutes, with the mediating role of job satisfaction. A sample of 341 faculty members from ten private higher education institutes in Lahore city of Pakistan, was selected through a stratified proportionate random sampling technique. A descriptive survey research approach was employed to collect data from 341 faculty members by administering a close-ended questionnaire based on a seven-point Likert scale as a self-administered research instrument. The study was conducted under the domain of the Leader-Member Exchange (LMX) theory. The mediating role of job satisfaction was measured by bootstrapping technique. The results revealed that servant leadership has a statistically significant influence on faculty retention, with a statistically significant mediating role of job satisfaction, in private higher education institutes in Pakistan. Further, up to the best of the authors’ knowledge, this is the first systematic and empirical study on faculty retention conducted against the backdrop of servant leadership in an Eastern context, particularly in Pakistan.

Keywords: servant leadership, faculty retention, job satisfaction, higher education institutes

Procedia PDF Downloads 81
7808 Assessment of Serum Osteopontin, Osteoprotegerin and Bone-Specific Alp as Markers of Bone Turnover in Patients with Disorders of Thyroid Function in Nigeria, Sub-Saharan Africa

Authors: Oluwabori Emmanuel Olukoyejo, Ogra Victor Ogra, Bosede Amodu, Tewogbade Adeoye Adedeji

Abstract:

Background: Disorders of thyroid function are the second most common endocrine disorders worldwide, with a direct relationship with metabolic bone diseases. These metabolic bone complications are often subtle but manifest as bone pains and an increased risk of fractures. The gold standard for diagnosis, Dual Energy X-ray Absorptiometry (DEXA), is limited in this environment due to unavailability, cumbersomeness and cost. However, bone biomarkers have shown prospects in assessing alterations in bone remodeling, which has not been studied in this environment. Aim: This study evaluates serum levels of bone-specific alkaline phosphatase (bone-specific ALP), osteopontin and osteoprotegerin biomarkers of bone turnover in patients with disorders of thyroid function. Methods: This is a cross-sectional study carried out over a period of one and a half years. Forty patients with thyroid dysfunctions, aged 20 to 50 years, and thirty-eight age and sex-matched healthy euthyroid controls were included in this study. Patients were further stratified into hyperthyroid and hypothyroid groups. Bone-specific ALP, osteopontin, and osteoprotegerin, alongside serum total calcium, ionized calcium and inorganic phosphate, were assayed for all patients and controls. A self-administered questionnaire was used to obtain data on sociodemographic and medical history. Then, 5 ml of blood was collected in a plain bottle and serum was harvested following clotting and centrifugation. Serum samples were assayed for B-ALP, osteopontin, and osteoprotegerin using the ELISA technique. Total calcium and ionized calcium were assayed using an ion-selective electrode, while the inorganic phosphate was assayed with automated photometry. Results: The hyperthyroid and hypothyroid patient groups had significantly increased median serum B-ALP (30.40 and 26.50) ng/ml and significantly lower median OPG (0.80 and 0.80) ng/ml than the controls (10.81 and 1.30) ng/ml respectively, p < 0.05. However, serum osteopontin in the hyperthyroid group was significantly higher and significantly lower in the hypothyroid group when compared with the controls (11.00 and 2.10 vs 3.70) ng/ml, respectively, p < 0.05. Both hyperthyroid and hypothyroid groups had significantly higher mean serum total calcium, ionized calcium and inorganic phosphate than the controls (2.49 ± 0.28, 1.27 ± 0.14 and 1.33 ± 0.33) mmol/l and (2.41 ± 0.04, 1.20 ± 0.04 and 1.15 ± 0.16) mmol/l vs (2.27 ± 0.11, 1.17 ± 0.06 and 1.08 ± 0.16) mmol/l respectively, p < 0.05. Conclusion: Patients with disorders of thyroid function have metabolic imbalances of all the studied bone markers, suggesting a higher bone turnover. The routine bone markers will be an invaluable tool for monitoring bone health in patients with thyroid dysfunctions, while the less readily available markers can be introduced as supplementary tools. Moreover, bone-specific ALP, osteopontin and osteoprotegerin were found to be the strongest independent predictors of metabolic bone markers’ derangements in patients with thyroid dysfunctions.

Keywords: metabolic bone diseases, biomarker, bone turnover, hyperthyroid, hypothyroid, euthyroid

Procedia PDF Downloads 36
7807 A Review of Effective Gene Selection Methods for Cancer Classification Using Microarray Gene Expression Profile

Authors: Hala Alshamlan, Ghada Badr, Yousef Alohali

Abstract:

Cancer is one of the dreadful diseases, which causes considerable death rate in humans. DNA microarray-based gene expression profiling has been emerged as an efficient technique for cancer classification, as well as for diagnosis, prognosis, and treatment purposes. In recent years, a DNA microarray technique has gained more attraction in both scientific and in industrial fields. It is important to determine the informative genes that cause cancer to improve early cancer diagnosis and to give effective chemotherapy treatment. In order to gain deep insight into the cancer classification problem, it is necessary to take a closer look at the proposed gene selection methods. We believe that they should be an integral preprocessing step for cancer classification. Furthermore, finding an accurate gene selection method is a very significant issue in a cancer classification area because it reduces the dimensionality of microarray dataset and selects informative genes. In this paper, we classify and review the state-of-art gene selection methods. We proceed by evaluating the performance of each gene selection approach based on their classification accuracy and number of informative genes. In our evaluation, we will use four benchmark microarray datasets for the cancer diagnosis (leukemia, colon, lung, and prostate). In addition, we compare the performance of gene selection method to investigate the effective gene selection method that has the ability to identify a small set of marker genes, and ensure high cancer classification accuracy. To the best of our knowledge, this is the first attempt to compare gene selection approaches for cancer classification using microarray gene expression profile.

Keywords: gene selection, feature selection, cancer classification, microarray, gene expression profile

Procedia PDF Downloads 454
7806 TiO₂ Nanotube Array Based Selective Vapor Sensors for Breath Analysis

Authors: Arnab Hazra

Abstract:

Breath analysis is a quick, noninvasive and inexpensive technique for disease diagnosis can be used on people of all ages without any risk. Only a limited number of volatile organic compounds (VOCs) can be associated with the occurrence of specific diseases. These VOCs can be considered as disease markers or breath markers. Selective detection with specific concentration of breath marker in exhaled human breath is required to detect a particular disease. For example, acetone (C₃H₆O), ethanol (C₂H₅OH), ethane (C₂H₆) etc. are the breath markers and abnormal concentrations of these VOCs in exhaled human breath indicates the diseases like diabetes mellitus, renal failure, breast cancer respectively. Nanomaterial-based vapor sensors are inexpensive, small and potential candidate for the detection of breath markers. In practical measurement, selectivity is the most crucial issue where trace detection of breath marker is needed to identify accurately in the presence of several interfering vapors and gases. Current article concerns a novel technique for selective and lower ppb level detection of breath markers at very low temperature based on TiO₂ nanotube array based vapor sensor devices. Highly ordered and oriented TiO₂ nanotube array was synthesized by electrochemical anodization of high purity tatinium (Ti) foil. 0.5 wt% NH₄F, ethylene glycol and 10 vol% H₂O was used as the electrolyte and anodization was carried out for 90 min with 40 V DC potential. Au/TiO₂ Nanotube/Ti, sandwich type sensor device was fabricated for the selective detection of VOCs in low concentration range. Initially, sensor was characterized where resistive and capacitive change of the sensor was recorded within the valid concentration range for individual breath markers (or organic vapors). Sensor resistance was decreased and sensor capacitance was increased with the increase of vapor concentration. Now, the ratio of resistive slope (mR) and capacitive slope (mC) provided a concentration independent constant term (M) for a particular vapor. For the detection of unknown vapor, ratio of resistive change and capacitive change at any concentration was same to the previously calculated constant term (M). After successful identification of the target vapor, concentration was calculated from the straight line behavior of resistance as a function of concentration. Current technique is suitable for the detection of particular vapor from a mixture of other interfering vapors.

Keywords: breath marker, vapor sensors, selective detection, TiO₂ nanotube array

Procedia PDF Downloads 155
7805 Teacher Education: Teacher Development and Support

Authors: Khadem Hichem

Abstract:

With the new technology challenges, dynamics and challenges of the contemporary world, most teachers are struggling to maintain effective and successful teaching /learning environment for learners. Teachers as a key to the success of reforms in the educational setting, they must improve their competencies to teach effectively. Many researchers emphasis on the ongoing professional development of the teacher by enhancing their experiences and encouraging their responsibility for learning, and thus promoting self-reliance, collaboration, and reflection. In short, teachers are considered as learners and they need to learn together. The educational system must support, both conceptually and financially, the teachers’ development as lifelong learners Teachers need opportunities to grow in language proficiency and in knowledge. Changing nature of language and culture in the world, all teachers must have opportunities to update their knowledge and practices. Many researchers in the field of foreign or additional languages indicate that teachers keep side by side of effective instructional practices and they need special support with the challenging task of developing and administering proficiency tests to their students. For significant change to occur, each individual teacher’s needs must be addressed. The teacher must be involved experientially in the process of development, since, by itself, knowledge of how to change does not mean change will be initiated. For improvement to occur, new skills have to be guided, practiced, and reflected upon in collaboration with colleagues. Clearly, teachers are at different places developmentally; therefore, allowances for various entry levels and individual differences need to be built into the professional development structure. Objectives must be meaningful to the participant and teacher improvement must be stated terms of student knowledge, student performance, and motivation. The most successful professional development process acknowledges the student-centered nature of good teaching. This paper highlights the importance of teacher professional development process and institutional supports as way to enhance good teaching and learning environment.

Keywords: teacher professional development, teacher competencies, institutional support, teacher education

Procedia PDF Downloads 354
7804 Artificial Neural Network in Ultra-High Precision Grinding of Borosilicate-Crown Glass

Authors: Goodness Onwuka, Khaled Abou-El-Hossein

Abstract:

Borosilicate-crown (BK7) glass has found broad application in the optic and automotive industries and the growing demands for nanometric surface finishes is becoming a necessity in such applications. Thus, it has become paramount to optimize the parameters influencing the surface roughness of this precision lens. The research was carried out on a 4-axes Nanoform 250 precision lathe machine with an ultra-high precision grinding spindle. The experiment varied the machining parameters of feed rate, wheel speed and depth of cut at three levels for different combinations using Box Behnken design of experiment and the resulting surface roughness values were measured using a Taylor Hobson Dimension XL optical profiler. Acoustic emission monitoring technique was applied at a high sampling rate to monitor the machining process while further signal processing and feature extraction methods were implemented to generate the input to a neural network algorithm. This paper highlights the training and development of a back propagation neural network prediction algorithm through careful selection of parameters and the result show a better classification accuracy when compared to a previously developed response surface model with very similar machining parameters. Hence artificial neural network algorithms provide better surface roughness prediction accuracy in the ultra-high precision grinding of BK7 glass.

Keywords: acoustic emission technique, artificial neural network, surface roughness, ultra-high precision grinding

Procedia PDF Downloads 305
7803 Immobilization of Lead in Contaminated Soil Using Enzyme Induced Calcite Precipitation (EİCP) Along with Coconut Fiber Biochar (CFB)

Authors: Kaniz Roksana, Aluthgun Hewage Shaini, Cheng Zhu

Abstract:

Lead is environmentally hazardous because it may persist for a long time in soil, water, and air, and it can travel large distances when carried by wind or water. Lead is toxic to many different species of organisms and has the potential to disrupt ecosystem stability. Moreover, lead can contaminate crops and livestock, which can then have an adverse effect on human health. This study was conducted to use the enzyme-induced calcium carbonate precipitation (EICP) technique from soybean crude extract urease along coconut fiber derived biochar’s (CFB) to bioremediate lead. To study the desorption rates of heavy metals from the soil, lead (Pb) was added to the soil at load ratios of 50 and 100 mg/kg. There were five separate treatment soil columns created: control sample, only CFB, only EICP, EICP with 2% (w/w) CFB, and EICP with 4% (w/w) CFB. Laboratory scale experiment demonstrates significant lead removal from soil. The amount of CaCO₃ precipitated in the soil was measured using a gravimetric acid digestion test, which related heavy metal desorption to the amount of precipitated calcium carbonate. These findings were validated using a scanning electron microscope (SEM), which revealed calcium carbonate and lead coprecipitation. As a result, the study reveals that the EICP technique, in conjunction with coconut fiber biochar, could be an efficient alternative in the remediation of heavy metal ion-contaminated soils.

Keywords: enzyme induced calcium carbonate precipitation (EICP), coconut fiber derived biochar’s (CFB), bioremediation, heavy metal

Procedia PDF Downloads 76
7802 Vehicle Gearbox Fault Diagnosis Based on Cepstrum Analysis

Authors: Mohamed El Morsy, Gabriela Achtenová

Abstract:

Research on damage of gears and gear pairs using vibration signals remains very attractive, because vibration signals from a gear pair are complex in nature and not easy to interpret. Predicting gear pair defects by analyzing changes in vibration signal of gears pairs in operation is a very reliable method. Therefore, a suitable vibration signal processing technique is necessary to extract defect information generally obscured by the noise from dynamic factors of other gear pairs. This article presents the value of cepstrum analysis in vehicle gearbox fault diagnosis. Cepstrum represents the overall power content of a whole family of harmonics and sidebands when more than one family of sidebands is present at the same time. The concept for the measurement and analysis involved in using the technique are briefly outlined. Cepstrum analysis is used for detection of an artificial pitting defect in a vehicle gearbox loaded with different speeds and torques. The test stand is equipped with three dynamometers; the input dynamometer serves as the internal combustion engine, the output dynamometers introduce the load on the flanges of the output joint shafts. The pitting defect is manufactured on the tooth side of a gear of the fifth speed on the secondary shaft. Also, a method for fault diagnosis of gear faults is presented based on order cepstrum. The procedure is illustrated with the experimental vibration data of the vehicle gearbox. The results show the effectiveness of cepstrum analysis in detection and diagnosis of the gear condition.

Keywords: cepstrum analysis, fault diagnosis, gearbox, vibration signals

Procedia PDF Downloads 379
7801 The Technique of Mobilization of the Colon for Pull-Through Procedure in Hirschsprung's Disease

Authors: Medet K. Khamitov, Marat M. Ospanov, Vasiliy M. Lozovoy, Zhenis N. Sakuov, Dastan Z. Rustemov

Abstract:

With a high rectosigmoid transitional zone in children with Hirschsprung’s disease, the upper rectal, sigmoid, left colon arteries are ligated during the pull-through of the descending part of the colon. As a result, the inferior mesenteric artery ceases to participate in the blood supply to the descending part of the colon. As a result, the reduced colon is supplied with blood only by the middle colon artery, which originates from the superior mesenteric artery. Insufficiency of blood supply to the reduced colon is the cause of the development of chronic hypoxia of the intestinal wall or necrosis of the reduced descending colon. Some surgeons prefer to preserve the left colon artery. However, it is possible to stretch the mesentery, which can lead to bowel retraction to anastomotic leaks and stenosis. Chronic hypoxia of the reduced colon, in turn, is the cause of acquired (secondary) aganglionosis. The highest frequency of anastomotic leaks is observed in children older than five years. The purpose is to reduce the risk of complications in the pull-through procedure of the descending part of the colon in patients with Hirschsprung’s disease by ensuring its sufficient mobility and maintaining blood supply to the lower mesenteric artery. Methodology and events. Two children aged 5 and 7 years with Hirschsprung’s disease were operated under the conditions of the hospital in Nur-Sultan. The diagnosis was made using x-ray contrast enema and histological examination. Operational technique. After revision of the left part of the colon and assessment of the architectonics of its blood vessels, parietal mobilization of the affected sigmoid and rectum was performed on laparotomy access, while maintaining the arterial and venous terminal arcades of the sigmoid vessels. Then, the descending branch of the left colon artery was crossed (if there is an insufficient length of the reduced intestine, the left colonic artery itself may also be crossed). This manipulation provides additional mobility of the pull-through descending part of the colon. The resulting "windows" in the mesentery of the reduced intestine were sutured to prevent the development of an internal hernia. Formed a full-blooded, sufficiently long transplant from the transverse loops of the splenic angle and the descending parts of the colon with blood supply from the upper and lower mesenteric artery, freely, without tension, is reduced to the rectal zone with the coloanal anastomosis 1.5 cm above the dentate line. Results. The postoperative period was uneventful. Patients were discharged on the 7th day. The observation was carried out for six months. In no case, there was a bowel retraction, anastomotic leak, anastomotic stenosis, or other complications. Conclusion. The presented technique of mobilization of the colon for the pull-through procedure in a high transitional rectosigmoid zone of Hirschsprung’s disease allows to maintain normal blood supply to the distal part of the colon and to avoid the tension of the colon. The technique allows reducing the risk of anastomotic leak, bowel necrosis, chronic ischemia, to exclude colon retraction and anastomotic stenosis.

Keywords: blood supply, children, colon mobilization, Hirschsprung's disease, pull-through

Procedia PDF Downloads 147
7800 Predicting Blockchain Technology Installation Cost in Supply Chain System through Supervised Learning

Authors: Hossein Havaeji, Tony Wong, Thien-My Dao

Abstract:

1. Research Problems and Research Objectives: Blockchain Technology-enabled Supply Chain System (BT-enabled SCS) is the system using BT to drive SCS transparency, security, durability, and process integrity as SCS data is not always visible, available, or trusted. The costs of operating BT in the SCS are a common problem in several organizations. The costs must be estimated as they can impact existing cost control strategies. To account for system and deployment costs, it is necessary to overcome the following hurdle. The problem is that the costs of developing and running a BT in SCS are not yet clear in most cases. Many industries aiming to use BT have special attention to the importance of BT installation cost which has a direct impact on the total costs of SCS. Predicting BT installation cost in SCS may help managers decide whether BT is to be an economic advantage. The purpose of the research is to identify some main BT installation cost components in SCS needed for deeper cost analysis. We then identify and categorize the main groups of cost components in more detail to utilize them in the prediction process. The second objective is to determine the suitable Supervised Learning technique in order to predict the costs of developing and running BT in SCS in a particular case study. The last aim is to investigate how the running BT cost can be involved in the total cost of SCS. 2. Work Performed: Applied successfully in various fields, Supervised Learning is a method to set the data frame, treat the data, and train/practice the method sort. It is a learning model directed to make predictions of an outcome measurement based on a set of unforeseen input data. The following steps must be conducted to search for the objectives of our subject. The first step is to make a literature review to identify the different cost components of BT installation in SCS. Based on the literature review, we should choose some Supervised Learning methods which are suitable for BT installation cost prediction in SCS. According to the literature review, some Supervised Learning algorithms which provide us with a powerful tool to classify BT installation components and predict BT installation cost are the Support Vector Regression (SVR) algorithm, Back Propagation (BP) neural network, and Artificial Neural Network (ANN). Choosing a case study to feed data into the models comes into the third step. Finally, we will propose the best predictive performance to find the minimum BT installation costs in SCS. 3. Expected Results and Conclusion: This study tends to propose a cost prediction of BT installation in SCS with the help of Supervised Learning algorithms. At first attempt, we will select a case study in the field of BT-enabled SCS, and then use some Supervised Learning algorithms to predict BT installation cost in SCS. We continue to find the best predictive performance for developing and running BT in SCS. Finally, the paper will be presented at the conference.

Keywords: blockchain technology, blockchain technology-enabled supply chain system, installation cost, supervised learning

Procedia PDF Downloads 122
7799 Psychological Factors Affecting Breastfeeding: An Exploratory Study among Breastfeeding Moms

Authors: Marwa Abdussalam

Abstract:

Breastfeeding is a unique emotional bond between a mother and their offspring. Though breastfeeding may be natural, it is not something mothers are born with; some still struggle to breastfeed their babies. Various factors can influence the breastfeeding experience, such as the mode of delivery, the mother’s health condition, proper latching, etc. In addition, psychological factors have been known to influence breastfeeding ability, duration, and milk supply. Some mothers struggle to breastfeed their babies because they perceive they have a low milk supply and or don’t have the ability to breastfeed their babies. Most of these perceptions result either from their own past experience or from the ‘comments’ of their caregivers. So, it is of utmost essential to understand such psychological factors affecting breastfeeding so that necessary steps can be taken to educate breastfeeding mothers. The study explored the role of psychological factors that affect breastfeeding. Data were collected from fifteen breastfeeding mothers using a semi-structured interview schedule. A total of 10 questions were included in the interview schedule. Questions were sequenced in a funnel pattern, beginning with open-ended questions and then moving on to close-ended questions. Data were analyzed using Braun and Clarke’s Thematic Analysis technique. This technique involves identifying the codes, generating themes, naming them, and finally reviewing them. Results indicated that breastfeeding self-efficacy perceived insufficient milk supply, and lack of knowledge were the psychological factors affecting breastfeeding. The results of this study can be used to help mothers who are struggling with breastfeeding by developing interventions aimed at improving breastfeeding self-efficacy.

Keywords: breastfeeding, breastfeeding self-efficacy, perceived insufficient milk supply, Thematic Analysis

Procedia PDF Downloads 108
7798 Time Effective Structural Frequency Response Testing with Oblique Impact

Authors: Khoo Shin Yee, Lian Yee Cheng, Ong Zhi Chao, Zubaidah Ismail, Siamak Noroozi

Abstract:

Structural frequency response testing is accurate in identifying the dynamic characteristic of a machinery structure. In practical perspective, conventional structural frequency response testing such as experimental modal analysis with impulse technique (also known as “impulse testing”) has limitation especially on its long acquisition time. The high acquisition time is mainly due to the redundancy procedure where the engineer has to repeatedly perform the test in 3 directions, namely the axial-, horizontal- and vertical-axis, in order to comprehensively define the dynamic behavior of a 3D structure. This is unfavorable to numerous industries where the downtime cost is high. This study proposes to reduce the testing time by using oblique impact. Theoretically, a single oblique impact can induce significant vibration responses and vibration modes in all the 3 directions. Hence, the acquisition time with the implementation of the oblique impulse technique can be reduced by a factor of three (i.e. for a 3D dynamic system). This study initiates an experimental investigation of impulse testing with oblique excitation. A motor-driven test rig has been used for the testing purpose. Its dynamic characteristic has been identified using the impulse testing with the conventional normal impact and the proposed oblique impact respectively. The results show that the proposed oblique impulse testing is able to obtain all the desired natural frequencies in all 3 directions and thus providing a feasible solution for a fast and time effective way of conducting the impulse testing.

Keywords: frequency response function, impact testing, modal analysis, oblique angle, oblique impact

Procedia PDF Downloads 501