Search results for: mixed method research
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 38668

Search results for: mixed method research

34078 Out-of-Plane Free Vibrations of Circular Rods

Authors: Faruk Firat Çalim, Nurullah Karaca, Hakan Tacettin Türker

Abstract:

In this study, out-of-plane free vibrations of a circular rods is investigated theoretically. The governing equations for naturally twisted and curved spatial rods are obtained using Timoshenko beam theory and rewritten for circular rods. Effects of the axial and shear deformations are considered in the formulations. Ordinary differential equations in scalar form are solved analytically by using transfer matrix method. The circular rods of the mass matrix are obtained by using straight rod of consistent mass matrix. Free vibrations frequencies obtained by solving eigenvalue problem. A computer program coded in MATHEMATICA language is prepared. Circular beams are analyzed through various examples for free vibrations analysis. Results are compared with ANSYS results based on finite element method and available in the literature.

Keywords: circular rod, out-of-plane free vibration analysis, transfer matrix method

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34077 Sea Border Dispute between Greece and Turkey in the Mediterrenean: Implications for Turkey’s Maritime Security and Its Military Spending

Authors: Aslihan Caliskan

Abstract:

The term Mediterranean comes from the Latin “mediterraneus” (Medius, "middle" plus Terra, "land, earth"). For the ancient Romans, the Mediterranean was the center of the earth as they knew it. The desire to gain control of the Mediterranean has led to disputes between many nations throughout history, some of which continue to this day. The recent major natural gas discoveries in the Mediterranean have aggravated ongoing tensions in some neighboring countries. The sea border dispute between Turkey and Greece & Greek-Cypriot side is one of the most critical conflicts in the Mediterranean Sea region. This unresolved dispute has many implications for all countries involved, as well as for third parties that have direct or indirect interests in the region. The research question of this context is what are the implications of this controversial sea border problem on the maritime security of Turkey and its military spending. In this paper, the quantitative method is used. Records from the Turkish Defense Ministry, data from the Turkish naval forces have been obtained. In addition, literature research and the United Nations Convention on the Law of the Sea (UNCLOS) application cases were evaluated, and an incident analysis was carried out. This research shows that the sea border dispute issue has a significant impact on the Turkish military both in terms of the structures required to ensure maritime and border security, as well as rising military costs and its macroeconomic implications. The paper begins with a brief overview of relevant principles and methods applied for delimiting th esea borders. The paper continues with a brief description and a background of the sea border dispute between Turkey and Greece & Greek-Cypriot side in the light of the United Nations Convention on the Law of the Sea (UNCLOS). An analysis of the implications of the dispute on Turkey’s maritime security and its military spending is provided in the following chapters. The paper ends with concluding remarks of the author, including suggestions for the way forward.

Keywords: sea border security, mediterranean sea, greece-turkey dispute, limitation of sea, united nations convention on the law of the sea (UNCLOS)

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34076 Improving the Electrical Conductivity of Epoxy Coating Using Carbon Nanotube by Electrodeposition Method

Authors: Mahla Zabet, Navid Zanganeh, Hafez Balavi, Farbod Sharif

Abstract:

Electrodeposition is a method for applying coatings with uniform thickness on complex objects. A conductive surface can be produced using the electrical current in this method. Carbon nanotubes are known to have high electrical conductivity and mechanical properties. In this report, NH2-multiwalled carbon nanotubes (MWCNTs) were used in epoxy resin with different weight percent. The weight percent of incorporated MWCNTS into the matrix was changed in the range of 0.6-3.6 wt% to obtain a series of electrocoatings. The electrocoats were then applied on steel substrates by a cathodic electrodeposition technique. Scanning electron microscopy (SEM) and optical microscopy were used to characterize the electrocoated films. The results illustrated the increase in conductivity by increasing of MWCNT load. However, at the percolation threshold, throwing power was dropped with increase in recoating ability.

Keywords: electrodeposition, carbon nanotube, electrical conductivity, throwing power

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34075 Insights into the Assessment of Intercultural Competence of Female University Students in the KSA

Authors: Agnes Havril

Abstract:

The aim of this paper is to introduce some partial findings of an ongoing research project which is investigating the improvement of intercultural competence of Saudi female university students in English as a Second Language academic environment at the multicultural Jazan University. Since previous research results support the idea that this university generation has the desire to become interculturally or globally competent university students, the present-day investigation is focusing on the assessment of Saudi-specific cultural terms and intercultural competence components in comparison with the Anglo-Saxon oriented western perspective of intercultural competence theories and models. On this stage of the research quantitative research methodology is applied and a survey is being conducted among the female university students in different academic specializations. This paper discusses some empirical data with the aim of identifying and evaluating certain supplementary aspects of intercultural dimensions and components of the intercultural competence construct. The research results also highlight several gender issues in the gender separated higher education in the Kingdom of Saudi Arabia.

Keywords: gender separation, globally competent university student, intercultural competence, intercultural competence construct, higher education

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34074 Marketing–Operations Alignment: A Systematic Literature and Citation Network Analysis Review

Authors: Kedwadee Sombultawee, Sakun Boon-Itt

Abstract:

This research demonstrates a systematic literature review of 62 peer-reviewed articles published in academic journals from 2000-2016 focusing on the operation and marketing interface area. The findings show the three major clusters of recent research domains, which is a review of the alignment between operations and marketing, identification of variables that impact the company and analysis of the effect of interface. Moreover, the Main Path Analysis (MPA) is mapped to show the knowledge structure of the operation and marketing interface issue. Most of the empirical research focused on company performance and new product development then analyzed the data by the structural equation model or regression. Whereas, some scholars studied the conflict of these two functions and proposed the requirement or step for alignment. Finally, the gaps in the literature are provided for future research directions.

Keywords: operations management, marketing, interface, systematic literature review

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34073 Intellectual Property in Digital Environment

Authors: Balamurugan L.

Abstract:

Artificial intelligence (AI) and its applications in Intellectual Property Rights (IPR) has been significantly growing in recent years. In last couple of years, AI tools for Patent Research and Patent Analytics have been well-stabilized in terms of accuracy of references and representation of identified patent insights. However, AI tools for Patent Prosecution and Patent Litigation are still in the nascent stage and there may be a significant potential if such market is explored further. Our research is primarily focused on identifying potential whitespaces and schematic algorithms to automate the Patent Prosecution and Patent Litigation Process of the Intellectual Property. The schematic algorithms may assist leading AI tool developers, to explore such opportunities in the field of Intellectual Property. Our research is also focused on identification of pitfalls of the AI. For example, Information Security and its impact in IPR, and Potential remediations to sustain the IPR in the digital environment.

Keywords: artificial intelligence, patent analytics, patent drafting, patent litigation, patent prosecution, patent research

Procedia PDF Downloads 54
34072 Pulmonary Valve Papillary Fibroelastoma: A Case Report of a Fibroelastoma Presenting as a Pulmonary Embolism

Authors: Frazer Kirk, Matthew Yong, Peter Williams, Andrie Strobel

Abstract:

Pulmonary valve papillary fibroelastoma is an exceedingly rare pathology. The experience and literature regarding them are largely anecdotal and based on sporadic, single case reports. Throughout their known history, two features remain salient that they are classically asymptomatic and found incidentally. The demographic profile of those affected is unclear, as reports regarding those affected are mixed, and there is no clear gender or age predominance, although there is some suggestion of a predisposition to affect females. Nor has there been a well-structured epidemiological study of the entity. Interestingly they are becoming more common on peri-mortum examination. Here-after we describe our experience with a symptomatic presentation of pulmonary papillary fibroelastoma masquerading as a pulmonary embolism and its subsequent assessment and management, with intraoperative photography and echocardiography for reference.

Keywords: cardiac tumor, pulmonary valve, fibroelastoma, cardiac surgery

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34071 Numerical Study on the Heat Transfer Characteristics of Composite Phase Change Materials

Authors: Gui Yewei, Du Yanxia, Xiao Guangming, Liu Lei, Wei Dong, Yang Xiaofeng

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A phase change material (PCM) is a substance which absorbs a large amount of energy when undergoing a change of solid-liquid phase. The good physical and chemical properties of C or SiC foam reveal the possibility of using them as a thermal conductivity enhancer for the PCM. C or SiC foam composite PCM has a high effective conductivity and becomes one of the most interesting thermal storage techniques due to its advantage of simplicity and reliability. The paper developed a numerical method to simulate the heat transfer of SiC and C foam composite PCM, a finite volume technique was used to discretize the heat diffusion equation while the phase change process was modeled using the equivalent specific heat method. The effects of the porosity were investigated based on the numerical method, and the effects of the geometric model of the microstructure on the equivalent thermal conductivity was studies.

Keywords: SiC foam, composite, phase change material, heat transfer

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34070 Waste Management in a Hot Laboratory of Japan Atomic Energy Agency – 1: Overview and Activities in Chemical Processing Facility

Authors: Kazunori Nomura, Hiromichi Ogi, Masaumi Nakahara, Sou Watanabe, Atsuhiro Shibata

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Chemical Processing Facility of Japan Atomic Energy Agency is a basic research field for advanced back-end technology developments with using actual high-level radioactive materials such as irradiated fuels from the fast reactor, high-level liquid waste from reprocessing plant. In the nature of a research facility, various kinds of chemical reagents have been offered for fundamental tests. Most of them were treated properly and stored in the liquid waste vessel equipped in the facility, but some were not treated and remained at the experimental space as a kind of legacy waste. It is required to treat the waste in safety. On the other hand, we formulated the Medium- and Long-Term Management Plan of Japan Atomic Energy Agency Facilities. This comprehensive plan considers Chemical Processing Facility as one of the facilities to be decommissioned. Even if the plan is executed, treatment of the “legacy” waste beforehand must be a necessary step for decommissioning operation. Under this circumstance, we launched a collaborative research project called the STRAD project, which stands for Systematic Treatment of Radioactive liquid waste for Decommissioning, in order to develop the treatment processes for wastes of the nuclear research facility. In this project, decomposition methods of chemicals causing a troublesome phenomenon such as corrosion and explosion have been developed and there is a prospect of their decomposition in the facility by simple method. And solidification of aqueous or organic liquid wastes after the decomposition has been studied by adding cement or coagulants. Furthermore, we treated experimental tools of various materials with making an effort to stabilize and to compact them before the package into the waste container. It is expected to decrease the number of transportation of the solid waste and widen the operation space. Some achievements of these studies will be shown in this paper. The project is expected to contribute beneficial waste management outcome that can be shared world widely.

Keywords: chemical processing facility, medium- and long-term management plan of JAEA facilities, STRAD project, treatment of radioactive waste

Procedia PDF Downloads 133
34069 A Social Network Analysis of the Palestinian Feminist Network Tal3at

Authors: Maath M. Musleh

Abstract:

This research aims to study recent trends in the Palestinian feminist movement through the case study of Tal3at. The study uses social network analysis as its primary method to analyze Twitter data. It attempts to interpret results through the lens of network theories and Parson’s AGIL paradigm. The study reveals major structural weaknesses in the Tal3at network. Our findings suggest that the movement will decline soon as sentiments of alienation amongst Palestinian women increases. These findings were validated by a couple of central actors in the network. This study contributes an SNA approach to the understanding of the understudied Palestinian feminism.

Keywords: feminism, Palestine, social network analysis, Tal3at

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34068 Method of Successive Approximations for Modeling of Distributed Systems

Authors: A. Torokhti

Abstract:

A new method of mathematical modeling of the distributed nonlinear system is developed. The system is represented by a combination of the set of spatially distributed sensors and the fusion center. Its mathematical model is obtained from the iterative procedure that converges to the model which is optimal in the sense of minimizing an associated cost function.

Keywords: mathematical modeling, non-linear system, spatially distributed sensors, fusion center

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34067 The Beam Expansion Method, A Simplified and Efficient Approach of Field Propagation and Resonators Modes Study

Authors: Zaia Derrar Kaddour

Abstract:

The study of a beam throughout an optical path is generally achieved by means of diffraction integral. Unfortunately, in some problems, this tool turns out to be not very friendly and hard to implement. Instead, the beam expansion method for computing field profiles appears to be an interesting alternative. The beam expansion method consists of expanding the field pattern as a series expansion in a set of orthogonal functions. Propagating each individual component through a circuit and adding up the derived elements leads easily to the result. The problem is then reduced to finding how the expansion coefficients change in a circuit. The beam expansion method requires a systematic study of each type of optical element that can be met in the considered optical path. In this work, we analyze the following fundamental elements: first order optical systems, hard apertures and waveguides. We show that the former element type is completely defined thanks to the Gouy phase shift expression we provide and the latters require a suitable mode conversion. For endorsing the usefulness and relevance of the beam expansion approach, we show here some of its applications such as the treatment of the thermal lens effect and the study of unstable resonators.

Keywords: gouy phase shift, modes, optical resonators, unstable resonators

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34066 Research on Community-based Nature Education Design at the Gateway Communities of National Parks

Authors: Yulin Liang

Abstract:

Under the background of protecting ecology, natural education is an effective way for people to understand nature. At the same time, it is a new means of sustainable development of eco-tourism, which can improve the functions of China 's protected areas and develop new business formats for the development of national parks. This study takes national park gateway communities as the research object and uses literature review, inductive reasoning and other research methods to sort out the development process of natural education in China and the research progress of natural education design in national park gateway communities. Finally, it discuss how gateway communities can use natural education to transform their development methods and provide theoretical and practical basis for the development of gateway communities in national parks.

Keywords: nature education, gateway communities, national park, sustainable development

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34065 Automatic Vehicle Detection Using Circular Synthetic Aperture Radar Image

Authors: Leping Chen, Daoxiang An, Xiaotao Huang

Abstract:

Automatic vehicle detection using synthetic aperture radar (SAR) image has been widely researched, as well as using optical remote sensing images. However, most researches treat the detection as an independent problem, failing to make full use of SAR data information. In circular SAR (CSAR), the two long borders of vehicle will shrink if the imaging surface is set higher than the reference one. Based on above variance, an automatic vehicle detection using CSAR image is proposed to enhance detection ability under complex environment, such as vehicles’ closely packing, which confuses the detector. The detection method uses the multiple images generated by different height plane to obtain an energy-concentrated image for detecting and then uses the maximally stable extremal regions method (MSER) to detect vehicles. A result of vehicles’ detection is given to verify the effectiveness and correctness of proposed method.

Keywords: circular SAR, vehicle detection, automatic, imaging

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34064 Perspective of Community Health Workers on The Sustainability of Primary Health Care

Authors: Dan Richard D. Fernandez

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This study determined the perspectives of community health workers’ perspectives in the sustainability of primary health care. Eight community health workers, two community officials and a rural health midwife in a rural community in the in the Philippines were enjoined to share their perspectives in the sustainability of primary health care. The study utilized the critical research method. The critical research assumes that there are ‘dominated’ or ‘marginalized’ groups whose interests are not best served by existing societal structures. Their experiences highlighted that the challenges of their role include unkind and uncooperative patients, the lack of institutional support mechanisms and conflict of their roles with their family responsibilities. Their most revealing insight is the belief that primary health care is within their grasp. Finally, they believe that the burden to sustain primary health care rests on their shoulders alone. This study establishes that Multi-stakeholder participation is and Gender-sensitivity is integral to the sustainability of Primary Health Care. It also observed that the ingrained Expert-Novice or Top-down Management Culture and the marginalisation of BHWs within the system is a threat to PHC sustainability. This study also recommends to expand the study and to involve the local government units and academe in lobbying the integration of gender-sensitivity and multi-stake participatory approaches to health workforce policies. Finally, this study recognised that the CHWs’ role is indispensable to the sustainability of primary health care.

Keywords: community health workers, multi-stakeholder participation, sustainability, gender-sensitivity

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34063 Comparative Performance of Standing Whole Body Monitor and Shielded Chair Counter for In-vivo Measurements

Authors: M. Manohari, S. Priyadharshini, K. Bajeer Sulthan, R. Santhanam, S. Chandrasekaran, B. Venkatraman

Abstract:

In-vivo monitoring facility at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, caters to the monitoring of internal exposure of occupational radiation workers from various radioactive facilities of IGCAR. Internal exposure measurement is done using Na(Tl) based Scintillation detectors. Two types of whole-body counters, namely Shielded Chair Counter (SC) and Standing Whole-Body Monitor (SWBM), are being used. The shielded Chair is based on a NaI detector of 20.3 cm diameter and 10.15 cm thick. The chair of the system is shielded using lead shots of 10 cm lead equivalent and the detector with 8 cm lead bricks. Counting geometry is sitting geometry. Calibration is done using 95 percentile BOMAB phantom. The minimum Detectable Activity (MDA) for 137Cs for the 60s is 1150 Bq. Standing Wholebody monitor (SWBM) has two NaI(Tl) detectors of size 10.16 x 10.16 x 40.64 cm3 positioned serially, one over the other. It has a shielding thickness of 5cm lead equivalent. Counting is done in standup geometry. Calibration is done with the help of Ortec Phantom, having a uniform distribution of mixed radionuclides for the thyroid, thorax and pelvis. The efficiency of SWBM is 2.4 to 3.5 times higher than that of the shielded chair in the energy range of 279 to 1332 keV. MDA of 250 Bq for 137Cs can be achieved with a counting time of 60s. MDA for 131I in the thyroid was estimated as 100 Bq from the MDA of whole-body for one-day post intake. Standing whole body monitor is better in terms of efficiency, MDA and ease of positioning. In case of emergency situations, the optimal MDAs for in-vivo monitoring service are 1000 Bq for 137Cs and 100 Bq for 131I. Hence, SWBM is more suitable for the rapid screening of workers as well as the public in the case of an emergency. While a person reports for counting, there is a potential for external contamination. In SWBM, there is a feasibility to discriminate them as the subject can be counted in anterior or posterior geometry which is not possible in SC.

Keywords: minimum detectable activity, shielded chair, shielding thickness, standing whole body monitor

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34062 A Machine Learning Approach for Detecting and Locating Hardware Trojans

Authors: Kaiwen Zheng, Wanting Zhou, Nan Tang, Lei Li, Yuanhang He

Abstract:

The integrated circuit industry has become a cornerstone of the information society, finding widespread application in areas such as industry, communication, medicine, and aerospace. However, with the increasing complexity of integrated circuits, Hardware Trojans (HTs) implanted by attackers have become a significant threat to their security. In this paper, we proposed a hardware trojan detection method for large-scale circuits. As HTs introduce physical characteristic changes such as structure, area, and power consumption as additional redundant circuits, we proposed a machine-learning-based hardware trojan detection method based on the physical characteristics of gate-level netlists. This method transforms the hardware trojan detection problem into a machine-learning binary classification problem based on physical characteristics, greatly improving detection speed. To address the problem of imbalanced data, where the number of pure circuit samples is far less than that of HTs circuit samples, we used the SMOTETomek algorithm to expand the dataset and further improve the performance of the classifier. We used three machine learning algorithms, K-Nearest Neighbors, Random Forest, and Support Vector Machine, to train and validate benchmark circuits on Trust-Hub, and all achieved good results. In our case studies based on AES encryption circuits provided by trust-hub, the test results showed the effectiveness of the proposed method. To further validate the method’s effectiveness for detecting variant HTs, we designed variant HTs using open-source HTs. The proposed method can guarantee robust detection accuracy in the millisecond level detection time for IC, and FPGA design flows and has good detection performance for library variant HTs.

Keywords: hardware trojans, physical properties, machine learning, hardware security

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34061 Use of Fine Recycled Aggregates in Normal Concrete Production

Authors: Vignesh Pechiappan Ayyathurai, Mukesh Limbachiya, Hsein Kew

Abstract:

There is a growing interest in using recycled, secondary use and industrial by product materials in high value commercial applications. Potential high volume applications include use of fine aggregate in flowable fill or as a component in manufactured aggregates. However, there is much scientific, as well as applied research needed in this area due to lack to availability of data on the mechanical and environmental properties of elements or products produced using fine recycled aggregates. The principle objectives of this research are to synthesize existing data on the beneficial reuse of fine recycled materials and to develop extensive testing programme for assessing and establishing engineering and long term durability properties of concrete and other construction products produced using such material for use in practical application widely. This paper is a research proposal for PhD admission. The proposed research aims to supply the necessary technical, as well as practical information on fine recycled aggregate concrete to the construction industry for promoting its wider use within the construction industry. Furthermore, to disseminate research outcomes to the local authorities for consideration of use of fine recycled aggregate concrete in various applications.

Keywords: FRA, fine aggregate, recycling, concrete

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34060 Isolation and Characterization of Ant-Salmonella Lactic Acid Bacteria from Dairy Products

Authors: Najie Hassanzade, Mohammad Rabbani Khorasgani

Abstract:

Dairy products have been regarded as the natural source of lactic acid bacteria with potential characteristics of probiotics; therefore, a lot of research and practical works have been carried out about the isolation of lactic acid bacteria (LAB) from dairy products, especially traditional yogurt and related products. Interest in traditional dairy products continues in the area of isolation of new LAB that can complement or replace currently used starters and/or that can be candidates as beneficial microorganisms for prevention or treatment purposes. In this perspective, such products are potentially good candidates for isolating new strains of probiotics. On the other hand, some infectious diseases such as salmonellosis have expressed resistance against many antibiotics; therefore, many attempts have been performed to use an alternative approach to overcome antibiotic resistance. The current research focuses on the isolation of LAB from dairy products, especially traditional dairy products and screening of them for anti-Salmonella activities. Twenty-five samples, including 15 sheep milk samples, one camel milk sample and seven cow milk samples from different areas of Iran and 2 yogurt samples from Herat, Afghanistan are collected. 20 bacteria are isolated by culturing the samples on MRS agar specific medium; among them 4 Lactobacillus strains, including 3L. plantarum strains and one L.gasseri strain, are identified by analyzing the biochemical tests and PCR tests in which 27F and 1492R primers are used. Then, their effects against Salmonella typhimurium using the well-diffusion method are evaluated.

Keywords: lactic acid bacteria, probiotics, dairy products Salmonella

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34059 Creativity and Innovation in Postgraduate Supervision

Authors: Rajendra Chetty

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The paper aims to address two aspects of postgraduate studies: interdisciplinary research and creative models of supervision. Interdisciplinary research can be viewed as a key imperative to solve complex problems. While excellent research requires a context of disciplinary strength, the cutting edge is often found at the intersection between disciplines. Interdisciplinary research foregrounds a team approach and information, methodologies, designs, and theories from different disciplines are integrated to advance fundamental understanding or to solve problems whose solutions are beyond the scope of a single discipline. Our aim should also be to generate research that transcends the original disciplines i.e. transdisciplinary research. Complexity is characteristic of the knowledge economy, hence, postgraduate research and engaged scholarship should be viewed by universities as primary vehicles through which knowledge can be generated to have a meaningful impact on society. There are far too many ‘ordinary’ studies that fall into the realm of credentialism and certification as opposed to significant studies that generate new knowledge and provide a trajectory for further academic discourse. Secondly, the paper will look at models of supervision that are different to the dominant ‘apprentice’ or individual approach. A reflective practitioner approach would be used to discuss a range of supervision models that resonate well with the principles of interdisciplinarity, growth in the postgraduate sector and a commitment to engaged scholarship. The global demand for postgraduate education has resulted in increased intake and new demands to limited supervision capacity at institutions. Team supervision lodged within large-scale research projects, working with a cohort of students within a research theme, the journal article route of doctoral studies and the professional PhD are some of the models that provide an alternative to the traditional approach. International cooperation should be encouraged in the production of high-impact research and institutions should be committed to stimulating international linkages which would result in co-supervision and mobility of postgraduate students and global significance of postgraduate research. International linkages are also valuable in increasing the capacity for supervision at new and developing universities. Innovative co-supervision and joint-degree options with global partners should be explored within strategic planning for innovative postgraduate programmes. Co-supervision of PhD students is probably the strongest driver (besides funding) for collaborative research as it provides the glue of shared interest, advantage and commitment between supervisors. The students’ field serves and informs the co-supervisors own research agendas and helps to shape over-arching research themes through shared research findings.

Keywords: interdisciplinarity, internationalisation, postgraduate, supervision

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34058 Investigating the Energy Gap and Wavelength of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ Superlattices in Terms of Material Thickness and Al Mole Fraction Using Empirical Tight-Binding Method

Authors: Matineh Sadat Hosseini Gheidari, Vahid Reza Yazdanpanah

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In this paper, we used the empirical tight-binding method (ETBM) with sp3s* approximation and considering the first nearest neighbor with spin-orbit interactions in order to model superlattice structure (SLS) of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ grown on GaAs (100) substrate at 300K. In the next step, we investigated the behavior of the energy gap and wavelength of this superlattice in terms of different thicknesses of core materials and Al mole fractions. As a result of this survey, we found out that as the Al composition increases, the energy gap of this superlattice has an upward trend and ranges from 1.42-1.63 eV. Also, according to the wavelength range that we gained from this superlattice in different Al mole fractions and various thicknesses, we can find a suitable semiconductor for a special light-emitting diode (LED) application.

Keywords: energy gap, empirical tight-binding method, light-emitting diode, superlattice, wavelength

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34057 Fractional Euler Method and Finite Difference Formula Using Conformable Fractional Derivative

Authors: Ramzi B. Albadarneh

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In this paper, we use the new definition of fractional derivative called conformable fractional derivative to derive some finite difference formulas and its error terms which are used to solve fractional differential equations and fractional partial differential equations, also to derive fractional Euler method and its error terms which can be applied to solve fractional differential equations. To provide the contribution of our work some applications on finite difference formulas and Euler Method are given.

Keywords: conformable fractional derivative, finite difference formula, fractional derivative, finite difference formula

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34056 Investigation of the Factors Influencing the Construction Planning Process Using Participant Observation Method

Authors: Ashokkumar Subbiah

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This study investigates the impact of factors that influenced the success of construction planning for a major construction project in Qatar. An approach of participant observation is adopted which is informed by the principles of ethnography: one that reports the participants’ view of their world rather than imposing an artificial theoretical framework upon it. As participant observant, key factors were observed and identified that had an impact on the management and execution of the construction planning. It is found that a ‘shadow culture’ exists between the project participants which, it is argued, is only observable from the perspective of an embedded participant observer. The shadow culture acts to enable the management of the planning process, and its efficacy relates to the ‘quality’ of human inter-relationships amongst immediate stakeholders. Whilst this study uses the concept of shadow culture, it is treated as both a methodological stance and one of the findings of this research in the context of the major construction project in Qatar. The concept of shadow culture is not imposed upon the findings, but instead is used as a research tool: respondents report their own worldview and this is reported from the view of a participant observant in a manner that is understandable and useful to those who are not part of the construction project. The findings of this study identify similar factors influencing the planning process of the Qatar project, but the shadow culture predominantly influences these factors towards the failure of planning process. The research concludes by questioning the assumption that construction planning is a mechanistic process that has to be conducted solely by the planning team. Instead, it is a highly social phenomenon in which the seemingly mechanistic process is made workable by the quality of relationships that exist in the project. Drawing on this the final section provides a series of recommendations that may be helpful in enhancing the efficacy of project planning; these include better training/education at the pre-construction phase; recognition of the importance of shadow processes at management levels, and better appreciation of the impact of contract type and chosen procurement route.

Keywords: construction planning, participant observation, project participants, shadow culture

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34055 Evaluation of the Impact of Community Based Disaster Risk Management Applied In Landslide Prone Area; Reference to Badulla District

Authors: S. B. D. Samarasinghe, Malini Herath

Abstract:

Participatory planning is a very important process for decision making and choosing the best alternative options for community welfare, development of the society and its interactions among community and professionals. People’s involvement is considered as the key guidance in participatory planning. Presently, Participatory planning is being used in many fields. It's not only limited to planning but also to disaster management, poverty, housing, etc. In the past, Disaster management practice was a top-down approach, but it raised many issues as it was converted to a bottom-up approach. There are several approaches that can aid disaster management. Community-Based Disaster Risk Management (CBDRM) is a very successful participatory approach to risk management that is often successfully applied by other disaster-prone countries. In the local context, CBDRM has been applied to prevent Diseases as well as to prevent disasters such as landslides, tsunamis and floods. From three years before, Sri Lanka has initiated the CBDRM approach to minimize landslide vulnerability. Hence, this study mainly focuses on the impact of CBDRM approaches on landslide hazards. Also to identify their successes and failures from both implementing parties and community. This research is carried out based on a qualitative method combined with a descriptive research approach. A successful framework was prepared via a literature review. Case studies were selected considering landslide CBDRM programs which were implemented by Disaster Management Center and National Building Research Organization in Badulla. Their processes were evaluated. Data collection is done through interviews and informal discussions. Then their ideas were quantified by using the Relative Effectiveness index. The resulting numerical value was used to rank the program effectiveness and their success, failures and impacting factors. Results show that there are several failures among implementing parties and the community. Overcoming those factors can make way for better conduction of future CBDRM programs.

Keywords: community-based disaster risk management, disaster management, preparedness, landslide

Procedia PDF Downloads 127
34054 Application Reliability Method for Concrete Dams

Authors: Mustapha Kamel Mihoubi, Mohamed Essadik Kerkar

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Probabilistic risk analysis models are used to provide a better understanding of the reliability and structural failure of works, including when calculating the stability of large structures to a major risk in the event of an accident or breakdown. This work is interested in the study of the probability of failure of concrete dams through the application of reliability analysis methods including the methods used in engineering. It is in our case, the use of level 2 methods via the study limit state. Hence, the probability of product failures is estimated by analytical methods of the type first order risk method (FORM) and the second order risk method (SORM). By way of comparison, a level three method was used which generates a full analysis of the problem and involves an integration of the probability density function of random variables extended to the field of security using the Monte Carlo simulation method. Taking into account the change in stress following load combinations: normal, exceptional and extreme acting on the dam, calculation of the results obtained have provided acceptable failure probability values which largely corroborate the theory, in fact, the probability of failure tends to increase with increasing load intensities, thus causing a significant decrease in strength, shear forces then induce a shift that threatens the reliability of the structure by intolerable values of the probability of product failures. Especially, in case the increase of uplift in a hypothetical default of the drainage system.

Keywords: dam, failure, limit-state, monte-carlo, reliability, probability, simulation, sliding, taylor

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34053 An Improved Circulating Tumor Cells Analysis Method for Identifying Tumorous Blood Cells

Authors: Salvador Garcia Bernal, Chi Zheng, Keqi Zhang, Lei Mao

Abstract:

Circulating Tumor Cells (CTC) is used to detect tumoral cell metastases using blood samples of patients with cancer (lung, breast, etc.). Using an immunofluorescent method a three channel image (Red, Green, and Blue) are obtained. These set of images usually overpass the 11 x 30 M pixels in size. An aided tool is designed for imaging cell analysis to segmented and identify the tumorous cell based on the three markers signals. Our Method, it is cell-based (area and cell shape) considering each channel information and extracting and making decisions if it is a valid CTC. The system also gives information about number and size of tumor cells found in the sample. We present results in real-life samples achieving acceptable performance in identifying CTCs in short time.

Keywords: Circulating Tumor Cells (CTC), cell analysis, immunofluorescent, medical image analysis

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34052 Efficient Sources and Methods of Extracting Water for Irrigation

Authors: Anthony Iyenjamu, Josiah Adeyemo

Abstract:

Due to the increasing water scarcity in South Africa, the prime focus of irrigation in South Africa shifts to creating feasible water sources and the efficient use of these sources. These irrigation systems in South Africa are implemented because of low and erratic rainfall and high evaporative demand. Irrigation contributes significantly to crop production in South Africa, as the mean annual precipitation for the country is usually less than 500mm. This is considered to be the minimum required for rain fed cropping. Even though the rainfall is low, a lot of the water in various areas in South Africa is lost due to runoff into storm water systems that run to the rivers and eventually into the sea. This study reviews the irrigation systems in South Africa which can be vastly improved by creating irrigation dams. A method of which may seem costly at first but rewarding with time. The study investigates the process of creating dam capacity capable of sustaining a suitable area size of land to be irrigated and thus diverting all runoff into these dams. This type of infrastructure method vastly improves various sectors in our irrigation systems. Extensive research is carried out in the surrounding area in which the dam should be constructed. Rainfall patterns and rainfall data is used for calculations of which period the dam will be at its optimum using rainfall. The size of the area irrigated was used to calculate the size of the irrigation dam to be constructed. The location of the dam must be situated as close to the river as possible to minimize the excessive use of pipelines to the dam. This study also investigated all existing resources to alleviate the cost. It was found that irrigation dams could solve the erratic distribution of rainfall in South Africa for irrigation purposes.

Keywords: irrigation, rainfed, rain harvesting, reservoir

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34051 Energy Loss Reduction in Oil Refineries through Flare Gas Recovery Approaches

Authors: Majid Amidpour, Parisa Karimi, Marzieh Joda

Abstract:

For the last few years, release of burned undesirable by-products has become a challenging issue in oil industries. Flaring, as one of the main sources of air contamination, involves detrimental and long-lasting effects on human health and is considered a substantial reason for energy losses worldwide. This research involves studying the implications of two main flare gas recovery methods at three oil refineries, all in Iran as the case I, case II, and case III in which the production capacities are increasing respectively. In the proposed methods, flare gases are converted into more valuable products, before combustion by the flare networks. The first approach involves collecting, compressing and converting the flare gas to smokeless fuel which can be used in the fuel gas system of the refineries. The other scenario includes utilizing the flare gas as a feed into liquefied petroleum gas (LPG) production unit already established in the refineries. The processes of these scenarios are simulated, and the capital investment is calculated for each procedure. The cumulative profits of the scenarios are evaluated using Net Present Value method. Furthermore, the sensitivity analysis based on total propane and butane mole fraction is carried out to make a rational comparison for LPG production approach, and the results are illustrated for different mole fractions of propane and butane. As the mole fraction of propane and butane contained in LPG differs in summer and winter seasons, the results corresponding to LPG scenario are demonstrated for each season. The results of the simulations show that cumulative profit in fuel gas production scenario and LPG production rate increase with the capacity of the refineries. Moreover, the investment return time in LPG production method experiences a decline, followed by a rising trend with an increase in C3 and C4 content. The minimum value of time return occurs at propane and butane sum concentration values of 0.7, 0.6, and 0.7 in case I, II, and III, respectively. Based on comparison of the time of investment return and cumulative profit, fuel gas production is the superior scenario for three case studies.

Keywords: flare gas reduction, liquefied petroleum gas, fuel gas, net present value method, sensitivity analysis

Procedia PDF Downloads 141
34050 Finite Element Modelling of Log Wall Corner Joints

Authors: Reza Kalantari, Ghazanfarah Hafeez

Abstract:

The paper presents outcomes of the numerical research performed on standard and dovetail corner joints under lateral loads. An overview of the past research on log shear walls is also presented. To the authors’ best knowledge, currently, there are no specific design guidelines available in the code for the design of log shear walls, implying the need to investigate the performance of log shear walls. This research explores the performance of the log shear wall corner joint system of standard joint and dovetail types using numerical methods based on research available in the literature. A parametric study is performed to study the effect of gap size provided between two orthogonal logs and the presence of wood and steel dowels provided as joinery between log courses on the performance of such a structural system. The research outcomes are the force-displacement curves. 8% variability is seen in the reaction forces with the change of gap size for the case of the standard joint, while a variation of 10% is observed in the reaction forces for the dovetail joint system.

Keywords: dovetail joint, finite element modelling, log shear walls, standard joint

Procedia PDF Downloads 200
34049 Caring for Children with Intellectual Disabilities in Malawi: Parental Psychological Experiences and Needs

Authors: Charles Masulani Mwale

Abstract:

Background: It is argued that 85% of children with the disability live in resource-poor countries where there are few available disability services. A majority of these children, including their parents, suffer a lot as a result of the disability and its associated stigmatization, leading to a marginalized life. These parents also experience more stress and mental health problems such as depression, compared with families of normal developing children. There is little research from Africa addressing these issues especially among parents of intellectually disabled children. WHO encourages research on the impact that child with a disability have on their family and appropriate training and support to the families so that they can promote the child’s development and well-being. This study investigated the parenting experiences, mechanisms of coping with these challenges and psychosocial needs while caring for children with intellectual disabilities in both rural and urban settings of Lilongwe and Mzuzu. Methods: This is part of a larger Mixed-methods study aimed at developing a contextualized psychosocial intervention for parents of intellectually disabled children. 16 focus group discussions and four in-depth interviews were conducted with parents in catchments areas for St John of God and Children of Blessings in Mzuzu and Lilongwe cities respectively. Ethical clearance was obtained from COMREC. Data were stored in NVivo software for easy retrieval and management. All interviews were tape-recorded, transcribed and translated into English. Note-taking was performed during all the observations. Data triangulation from the interviews, note taking and the observations were done for validation and reliability. Results: Caring for intellectually disabled children comes with a number of challenges. Parents experience stigma and discrimination; fear for the child’s future; have self-blame and guilt; get coerced by neighbors to kill the disabled child; and fear violence by and to the child. Their needs include respite relief, improved access to disability services, education on disability management and financial support. For their emotional stability, parents cope by sharing with others and turning to God while other use poor coping mechanisms like alcohol use. Discussion and Recommendation: Apart from neighbors’ coercion to eliminate the child life, the findings of this study are similar to those done in other countries like Kenya and Pakistan. It is recommended that parents get educated on disability, its causes, and management to array fears of unknown. Community education is also crucial to promote community inclusiveness and correct prevailing myths associated with disability. Disability institutions ought to intensify individual as well as group counseling services to these parents. Further studies need to be done to design culturally appropriate and specific psychosocial interventions for the parents to promote their psychological resilience.

Keywords: psychological distress, intellectual disability, psychosocial interventions, mental health, psychological resilience, children

Procedia PDF Downloads 426