Search results for: wider root angle

Authors: Sarathlal Koyiloth Vayalil, Stephan V. Roth, Gonzalo Santoro, Peng Zhang, Matthias Schwartzkopf, Bjoern Beyersdorff

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Nanostructured magnetic thin films have gained significant relevance due to its applications in magnetic storage and recording media. Self-organized arrays of nanoparticles and nanowires can be produced by depositing metal thin films on nano-rippled substrates. The substrate topography strongly affects the film growth giving rise to anisotropic properties (optical, magnetic, electronic transport). Ion-beam erosion (IBE) method can provide large-area patterned substrates with the valuable possibility to widely modify pattern length scale by simply acting on ion beam parameters (i.e. energy, ions, geometry, etc.). In this work, investigation of the growth mechanism of Permalloy thin films on such nano-rippled Si (100) substrates using in situ grazing incidence small angle x-ray scattering measurements (GISAXS) have been done. In situ GISAXS measurements during the deposition of thin films have been carried out at the P03/MiNaXS beam line of PETRA III storage ring of DESY, Hamburg. Nanorippled Si substrates prepared by low energy ion beam sputtering with an average wavelength of 33 nm and 1 nm have been used as templates. It has been found that the film replicates the morphology up to larger thickness regimes and also the growth is highly anisotropic along and normal to the ripple wave vectors. Various growth regimes have been observed. Further, magnetic measurements have been done using magneto-optical Kerr effect by rotating the sample in the azimuthal direction. Strong uniaxial magnetic anisotropy with its easy axis in a direction normal to the ripple wave vector has been observed. The strength of the magnetic anisotropy is found to be decreasing with increasing thin film thickness values. The mechanism of the observed strong uniaxial magnetic anisotropy and its depends on the thickness of the film has been explained by correlating it with the GISAXS results. In conclusion, we have done a detailed growth analysis of Permalloy thin films deposited on nanorippled Si templates and tried to explain the correlation between structure, morphology to the observed magnetic properties.

Keywords: grazing incidence small angle x-ray scattering, magnetic thin films, magnetic anisotropy, nanoripples

Procedia PDF Downloads 309

Authors: Sonia Arradaza-Pajaron

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This study examined the relationship between transformational leadership (TL) and self-efficacy (SE) of academic heads in the implementation of a customized English language curriculum (CELC) among technological state universities and colleges in Leyte provinces and Biliran, Philippines. Results manifested that academic leaders practiced transformational leadership and are self-efficacious enough but with only moderate level in the effectiveness of CELC implementation. It was found out; further, that of the four identified transformational leadership components, except idealized influence, three of which demonstrated a significant relationship with CELC component variables, although in varying degree. Moreover, self-efficacy sources, especially vicarious experiences and verbal persuasion manifested moderate to high significant relationships with effective CELC curriculum implementation. Further, verbal persuasion and physiological/emotional condition manifested significant relationship with CELC-resource and CELC-contextual/community influence, respectively. Regression analysis showed that TL-individualized consideration component explained wider extent when correlated with CELC contextual/community components, while self-efficacy source-verbal persuasion demonstrated a wider extent with the three CELC components, namely; resource, process and physiological/emotional condition. Results further revealed that TL-individualized consideration manifested lesser influence with CELC implementation, while SE-verbal persuasion demonstrated stronger influence or effect on CELC-process, CELC-physiological/emotional, while lesser influence with CELC-resource. This implies that academic leaders, in order to carry out effective curriculum implementation, should provide more emphasis on school culture, its beliefs, practices and academic atmosphere but most of all empower human resources who are considered the backbone of the work place and can be directly affected by any curriculum shifts and challenges. To realize this, more values-skilled training programs must be designed for academic heads are needed to equip them with the necessary leadership skills, beliefs in their capacity to lead and their own enhance emotional well-being in leading subordinates and facilitating curriculum implementation.

Keywords: Customized English Language curriculum, CELC, self-efficacy, transformational leadership, values-skilled training

Procedia PDF Downloads 120

Authors: C. Bateira, J. Fernandes, A. Costa

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The Douro Demarked Region (DDR) is a production Porto wine region. On the NE of Portugal, the strong incision of the Douro valley developed very steep slopes, organized with agriculture terraces, have experienced an intense and deep transformation in order to implement the mechanization of the work. The old terrace system, based on stone vertical wall support structure, replaced by terraces with earth embankments experienced a huge terrace instability. This terrace instability has important economic and financial consequences on the agriculture enterprises. This paper presents and develops cartographic tools to access the embankment instability and identify the area prone to instability. The priority on this evaluation is related to the use of physically based mathematical models and develop a validation process based on an inventory of the past embankment instability. We used the shallow landslide stability model (SHALSTAB) based on physical parameters such us cohesion (c’), friction angle(ф), hydraulic conductivity, soil depth, soil specific weight (ϱ), slope angle (α) and contributing areas by Multiple Flow Direction Method (MFD). A terraced area can be analysed by this models unless we have very detailed information representative of the terrain morphology. The slope angle and the contributing areas depend on that. We can achieve that propose using digital elevation models (DEM) with great resolution (pixel with 40cm side), resulting from a set of photographs taken by a flight at 100m high with pixel resolution of 12cm. The slope angle results from this DEM. In the other hand, the MFD contributing area models the internal flow and is an important element to define the spatial variation of the soil saturation. That internal flow is based on the DEM. That is supported by the statement that the interflow, although not coincident with the superficial flow, have important similitude with it. Electrical resistivity monitoring values which related with the MFD contributing areas build from a DEM of 1m resolution and revealed a consistent correlation. That analysis, performed on the area, showed a good correlation with R2 of 0,72 and 0,76 at 1,5m and 2m depth, respectively. Considering that, a DEM with 1m resolution was the base to model the real internal flow. Thus, we assumed that the contributing area of 1m resolution modelled by MFD is representative of the internal flow of the area. In order to solve this problem we used a set of generalized DEMs to build the contributing areas used in the SHALSTAB. Those DEMs, with several resolutions (1m and 5m), were built from a set of photographs with 50cm resolution taken by a flight with 5km high. Using this maps combination, we modelled several final maps of terrace instability and performed a validation process with the contingency matrix. The best final instability map resembles the slope map from a DEM of 40cm resolution and a MFD map from a DEM of 1m resolution with a True Positive Rate (TPR) of 0,97, a False Positive Rate of 0,47, Accuracy (ACC) of 0,53, Precision (PVC) of 0,0004 and a TPR/FPR ratio of 2,06.

Keywords: agricultural terraces, cartography, landslides, SHALSTAB, vineyards

Procedia PDF Downloads 176

Authors: Gizem Derya Demir, Ilayda Yankilic, Daglar Karamuftuoglu, Dante Dorantes

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ABSTRACT HAPTIC ROBOTIC GLOVE FOR TELE-EXPLORATION OF EXPLOSIVE DEVICES Gizem Derya Demir, İlayda Yankılıç, Dağlar Karamüftüoğlu, Dante J. Dorantes-González Department of Mechanical Engineering, MEF University Ayazağa Cad. No.4, 34396 Maslak, Sarıyer, İstanbul, Turkey Nowadays, terror attacks are, unfortunately, a more common threat around the world. Therefore, safety measures have become much more essential. An alternative to providing safety and saving human lives is done by robots, such as disassembling and liquidation of bombs. In this article, remote exploration and manipulation of potential explosive devices from a safe-distance are addressed by designing a novel, simple and ergonomic haptic robotic glove. SolidWorks® Computer-Aided Design, computerized dynamic simulation, and MATLAB® kinematic and static analysis were used for the haptic robotic glove and finger design. Angle controls of servo motors were made using ARDUINO® IDE codes on a Makeblock® MegaPi control card. Simple grasping dexterity solutions for the fingers were obtained using one linear soft and one angle sensors for each finger, and six servo motors are used in total to remotely control a slave multi-tooled robotic hand. This project is still undergoing and presents current results. Future research steps are also presented.

Keywords: Dexterity, Exoskeleton, Haptics , Position Control, Robotic Hand , Teleoperation

Procedia PDF Downloads 175

Authors: Navneet Singh Deora, Aastha Deswal, H. N. Mishra

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Pasta is one of the most widely consumed food products around the world. Rapid determination of the moisture content in pasta will assist food processors to provide online quality control of pasta during large scale production. Rapid Fourier transform near-infrared method (FT-NIR) was developed for determining moisture content in pasta. A calibration set of 150 samples, a validation set of 30 samples and a prediction set of 25 samples of pasta were used. The diffuse reflection spectra of different types of pastas were measured by FT-NIR analyzer in the 4,000-12,000 cm-1 spectral range. Calibration and validation sets were designed for the conception and evaluation of the method adequacy in the range of moisture content 10 to 15 percent (w.b) of the pasta. The prediction models based on partial least squares (PLS) regression, were developed in the near-infrared. Conventional criteria such as the R2, the root mean square errors of cross validation (RMSECV), root mean square errors of estimation (RMSEE) as well as the number of PLS factors were considered for the selection of three pre-processing (vector normalization, minimum-maximum normalization and multiplicative scatter correction) methods. Spectra of pasta sample were treated with different mathematic pre-treatments before being used to build models between the spectral information and moisture content. The moisture content in pasta predicted by FT-NIR methods had very good correlation with their values determined via traditional methods (R2 = 0.983), which clearly indicated that FT-NIR methods could be used as an effective tool for rapid determination of moisture content in pasta. The best calibration model was developed with min-max normalization (MMN) spectral pre-processing (R2 = 0.9775). The MMN pre-processing method was found most suitable and the maximum coefficient of determination (R2) value of 0.9875 was obtained for the calibration model developed.

Keywords: FT-NIR, pasta, moisture determination, food engineering

Procedia PDF Downloads 257

Authors: Pearl K. Atuhaire, Sylvia Kaye

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While the need for equal access to civil, political as well as economic, social and cultural rights is clear under the international law, the adoption of the Convention on the Elimination of all forms of Discrimination against women in 1979 made this even clearer. Despite this positive progress, the abuse of refugee women's rights is one of the basic underlying root causes of their marginalisation and violence in their countries of asylum. This paper presents a critical review on the development of refugee women's rights at the international levels and national levels. It provides an array of scholarly literature on this issue and examines the measures taken by the international community to curb the problem of violence against women in their various provisions through the instruments set. It is cognizant of the fact that even if conflict affects both refugee women and men, the effects on women refugees are deep-reaching, due to the cultural strongholds they face. An important aspect of this paper is that it is conceptualised against the fact that refugee women face the problem of sexual and gender based first as refugees and second as women, yet, their rights are stumbled upon. Often times they have been rendered "worthless victims" who are only in need of humanitarian assistance than active participants committed to change their plight through their participation in political, economic and social participation in their societies. Scholars have taken notice of the fact that women's rights in refugee settings have been marginalized and call for a need to incorporate their perspectives in the planning and management of refugee settings in which they live. Underpinning this discussion is feminism theory which gives a clear understanding of the root cause of refugee women's problems. Finally, this paper suggests that these policies should be translated into action at local, national international and regional levels to ensure sustainable peace.

Keywords: feminism theory, human rights, refugee women, sexual and gender based violence

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Authors: Shreekumari Patel, Prabhjot Kaur, Paras Solanki

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Moon Mineralogy Mapper (M3), Miniature Radio Frequency (Mini-RF), Kaguya Terrain Camera images, Lunar Orbiter Laser Altimeter (LOLA) digital elevation model (DEM) and Lunar Reconnaissance Orbiter Camera (LROC)- Narrow angle camera (NAC) and Wide angle camera (WAC) images were used to study mineralogy, surface physical properties, and age of the 42 km diameter Kopff crater. M3 indicates the low albedo crater floor to be high-Ca pyroxene dominated associated with floor fracture suggesting the igneous activity of the gabbroic material. Signature of anorthositic material is sampled on the eastern edge as target material is excavated from ~3 km diameter impact crater providing access to the crustal composition. Several occurrences of spinel were detected in northwestern rugged terrain. Our observation can be explained by exposure of spinel by this crater that impacted onto the inner rings of Orientale basin. Spinel was part of the pre-impact target, an intrinsic unit of basin ring. Crater floor was dated by crater counts performed on Kaguya TC images. Nature of surface was studied in detail with LROC NAC and Mini-RF. Freshly exposed surface and boulder or debris seen in LROC NAC images have enhanced radar signal in comparison to mature terrain of Kopff crater. This multidisciplinary analysis of remote sensing data helps to assess lunar surface in detail.

Keywords: crater, mineralogy, moon, radar observations

Procedia PDF Downloads 159

Authors: Asuman Baldiran, Erdener Pehlivan

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In this study, the root of the name Lykaonia and the geographical area defined as Lykaonia Region are mentioned. In this context, information concerning the settlements of Paleolithic Age, Neolithic Age and Chalcolithic Age are given place. Particularly the settlements belonging to Classical Age are localized and brief information about the history of these settlements is provided. In the light of this information, roads of Antique period in the region are evaluated.

Keywords: ancient cities, central anatolia, historical geography, Lykaonia region

Procedia PDF Downloads 377

Authors: Serdal Sabanci, Mutlu Çevik, Derya Tezcan, Cansu Çelebi, Filiz Içier

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Ultrasound is defined as sound waves having frequencies higher than 20 kHz, which is greater than the limits of the human hearing range. In recent years, ultrasonic treatment is an emerging technology being used increasingly in the food industry. It is applied as an alternative technique for different purposes such as microbial and enzyme inactivation, extraction, drying, filtration, crystallization, degas, cutting etc. Red beetroot (Beta vulgaris L.) is a root vegetable which is rich in mineral components, folic acid, dietary fiber, anthocyanin pigments. In this study, the application of low frequency high intensity ultrasound to the red beetroot slices and red beetroot juice for different treatment times (0, 5, 10, 15, 20 min) was investigated. Ultrasonicated red beetroot slices were also squeezed immediately. Changes on colour, betanin, pH and titratable acidity properties of red beetroot juices (the ultrasonicated juice (UJ) and the juice from ultrasonicated slices (JUS)) were determined. Although there was no significant difference statistically in the changes of color value of JUS samples due to ultrasound application (p>0.05), the color properties of UJ samples ultrasonicated for low durations were statistically different from raw material (p<0.05). The difference between color values of UJ and raw material disappeared (p>0.05) as the ultrasonication duration increased. The application of ultrasound to red beet root slices adversely affected and decreased the betanin content of JUS samples. On the other hand, the betanin content of UJ samples increased as the ultrasonication duration increased. Ultrasound treatment did not affect pH and titratable acidity of red beetroot juices statistically (p>0.05). The results suggest that ultrasound technology is the simple and economical technique which may successfully be employed for the processing of red beetroot juice with improved color and betanin quality. However, further investigation is still needed to confirm this.

Keywords: red beetroot, ultrasound, color, betanin

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Authors: Young Hee Geum

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We compare optimal quartic order method for the multiple zeros of nonlinear equations illustrating the basins of attraction. To construct basins of attraction effectively, we take a 600×600 uniform grid points at the origin of the complex plane and paint the initial values on the basins of attraction with different colors according to the iteration number required for convergence.

Keywords: basins of attraction, convergence, multiple-root, nonlinear equation

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Authors: Alireza Rasekh, Peter Sergeant, Jan Vierendeels

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This paper copes with the numerical simulation for convective heat transfer in the stator disk of an axial flux permanent magnet (AFPM) electrical machine. Overheating is one of the main issues in the design of AFMPs, which mainly occurs in the stator disk, so that it needs to be prevented. A rotor-stator configuration with 16 magnets at the periphery of the rotor is considered. Air is allowed to flow through openings in the rotor disk and channels being formed between the magnets and in the gap region between the magnets and the stator surface. The rotating channels between the magnets act as a driving force for the air flow. The significant non-dimensional parameters are the rotational Reynolds number, the gap size ratio, the magnet thickness ratio, and the magnet angle ratio. The goal is to find correlations for the Nusselt number on the stator disk according to these non-dimensional numbers. Therefore, CFD simulations have been performed with the multiple reference frame (MRF) technique to model the rotary motion of the rotor and the flow around and inside the machine. A minimization method is introduced by a pattern-search algorithm to find the appropriate values of the reference temperature. It is found that the correlations are fast, robust and is capable of predicting the stator heat transfer with a good accuracy. The results reveal that the magnet angle ratio diminishes the stator heat transfer, whereas the rotational Reynolds number and the magnet thickness ratio improve the convective heat transfer. On the other hand, there a certain gap size ratio at which the stator heat transfer reaches a maximum.

Keywords: AFPM, CFD, magnet parameters, stator heat transfer

Procedia PDF Downloads 249

Authors: Luiz G. Véras, Felipe L. Medeiros, Lamartine F. Guimarães

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This work approaches the automatic planning of paths for Unmanned Aerial Vehicles (UAVs) through the application of the Rapidly Exploring Random Tree Star-Smart (RRT*-Smart) algorithm. RRT*-Smart is a sampling process of positions of a navigation environment through a tree-type graph. The algorithm consists of randomly expanding a tree from an initial position (root node) until one of its branches reaches the final position of the path to be planned. The algorithm ensures the planning of the shortest path, considering the number of iterations tending to infinity. When a new node is inserted into the tree, each neighbor node of the new node is connected to it, if and only if the extension of the path between the root node and that neighbor node, with this new connection, is less than the current extension of the path between those two nodes. RRT*-smart uses an intelligent sampling strategy to plan less extensive routes by spending a smaller number of iterations. This strategy is based on the creation of samples/nodes near to the convex vertices of the navigation environment obstacles. The planned paths are smoothed through the application of the method called quintic pythagorean hodograph curves. The smoothing process converts a route into a dynamically-viable one based on the kinematic constraints of the vehicle. This smoothing method models the hodograph components of a curve with polynomials that obey the Pythagorean Theorem. Its advantage is that the obtained structure allows computation of the curve length in an exact way, without the need for quadratural techniques for the resolution of integrals.

Keywords: path planning, path smoothing, Pythagorean hodograph curve, RRT*-Smart

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Authors: Valeria Minucciani, Maria Maddalena Margaria

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While mathematical tools that make digital architecture possible are very sophisticated and advanced, theoretical development of digital architecture (intended as a discipline that integrates or replaces the real architecture) is not. The fashion show, that involves interiors architecture, exhibit design and scenography, has been exploiting for ten years the opportunities offered by digital technologies. To gain greater visibility and to reach a wider audience, high-level experimentations have been performed. The aim of this paper is in investigating, through the analysis of some cases of virtual fashion shows, the 'architectural' impact of the virtual conception of interior space.

Keywords: digital interiors, exhibit, fashion catwalk, architectural theory

Procedia PDF Downloads 423

Authors: M. Abbasi

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A spillway structure is used to pass excess water and floods from upstream or upstream to downstream or tributary. The spillway is considered one of the most key members of the dam, and the failure of many dams is attributed to the inefficiency of their spillway. Weirs should be selected as strong, reliable and high-performance structures, and weirs should be ready for use in all conditions and able to drain the flood so that we do not witness many casualties and financial losses when a flood occurs. The purpose of this study is to simulate the flow pattern passing over the peak spillway in order to optimize and adjust the height of the spillway walls. In this research, the effect of the shape of the side wings on the flow pattern over the peak spillways of the Gotvand reservoir dam was simulated and modelled using Flow3D software. In this research, side wings with rounded walls with six different approach angles were used. In addition, the different value of H/Hd was used to check the effect of the tank head. The results showed that with the constant H/Hd ratio and the increase of the approach angle of the side wing, the flow depth first decreases and then increases. These changes were the opposite regarding the depth average speed of the flow and the depth average concentration of the air entering the flow. At the same time, with the constant angle of approach of the side wing and with the increase of H/Hd ratio, the flow depth increases. In general, a correct understanding of the operation of overflows and a correct design can significantly reduce construction costs and solve flooding problems.

Keywords: effect of the shape, gotvand reservoir dam, narrowing coefficients, supports of the gates

Procedia PDF Downloads 64

Authors: Ruiyang Bi

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Natural rock masses are cut into rock blocks of different shapes and sizes by intersecting joints. These rock blocks often determine the mechanical properties of the rock mass. In this study, fine sandstone cube specimens were produced, and three intersecting joint cracks were cut inside the specimen. Uniaxial compression tests were conducted using mechanical tests and numerical simulation methods to study the mechanical properties and crack propagation mechanism of triangular blocks within the rock. During the test, the mechanical strength, acoustic emission characteristics and strain field evolution of the specimen were analyzed. Discrete element software was used to study the expansion of microcracks during the specimen failure process, and the crack types were divided. The simulation results show that as the inclination angles of the three joints increase simultaneously, the mechanical strength of the specimen first decreases and then increases, and the crack type is mainly shear. As the inclination angle of a single joint increases, the strength of the specimen gradually decreases. When the inclination angles of the two joints increase at the same time, the strength of the specimen gradually decreases. The research results show that the stability of the rock mass is affected by the joint inclination angle and the size of the cut blocks. The greater the joint dip and block size, the more significant the development of micro-cracks in the rock mass, and the worse the stability.

Keywords: rock joints, uniaxial compression, crack extension, discrete element simulation

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Authors: M. F. M. Ali, A. R. Ismail, B. M. Deros

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Soccer is very popular and ranked as the top sports in the world as well as in Malaysia. Although soccer sport in Malaysia is currently professionalized, but it’s plunging achievements within recent years continue and are not to be proud of. After review, the Malaysian soccer players are still weak in terms of kicking techniques. The instep kick is a technique, which is often used in soccer for the purpose of short passes and making a scoring. This study presents the 3D biomechanics analysis on a soccer player during performing instep kick. This study was conducted to determine the optimization value for approach angle, distance of supporting leg from the ball and ball internal pressure respect to the knee angular velocity of the ball on the kicking leg. Six subjects from different categories using dominant right leg and free from any injury were selected to take part in this study. Subjects were asked to perform one step instep kick according to the setting for the variables with different parameter. Data analysis was performed using 3 Dimensional “Qualisys Track Manager” system and will focused on the bottom of the body from the waist to the ankle. For this purpose, the marker will be attached to the bottom of the body before the kicking is perform by the subjects. Statistical analysis was conducted by using Minitab software using Response Surface Method through Box-Behnken design. The results of this study found the optimization values for all three parameters, namely the approach angle, 53.6º, distance of supporting leg from the ball, 8.84sm and ball internal pressure, 0.9bar with knee angular velocity, 779.27 degrees/sec have been produced.

Keywords: biomechanics, instep kick, soccer, optimization

Procedia PDF Downloads 229

Authors: Sarah Fitzpatrick, Hossein Zare-Behtash, Konstantinos Kontis

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Traditionally, the focus of horizontal axis wind turbine (HAWT) blade aerodynamic optimisation studies has been the outer working region of the blade. However, recent works seek to better understand, and thus improve upon, the performance of the inboard blade region to enhance power production, maximise load reduction and better control the wake behaviour. This paper presents the design considerations and characterisation of a wind turbine wind tunnel model devised to further the understanding and fundamental definition of horizontal axis wind turbine root vortex shedding and interactions. Additionally, the application of passive and active flow control mechanisms – vortex generators and plasma actuators – to allow for the manipulation and mitigation of unsteady aerodynamic behaviour at the blade inboard section is investigated. A static, modular blade wind turbine model has been developed for use in the University of Glasgow’s de Havilland closed return, low-speed wind tunnel. The model components - which comprise of a half span blade, hub, nacelle and tower - are scaled using the equivalent full span radius, R, for appropriate Mach and Strouhal numbers, and to achieve a Reynolds number in the range of 1.7x105 to 5.1x105 for operational speeds up to 55m/s. The half blade is constructed to be modular and fully dielectric, allowing for the integration of flow control mechanisms with a focus on plasma actuators. Investigations of root vortex shedding and the subsequent wake characteristics using qualitative – smoke visualisation, tufts and china clay flow – and quantitative methods – including particle image velocimetry (PIV), hot wire anemometry (HWA), and laser Doppler anemometry (LDA) – were conducted over a range of blade pitch angles 0 to 15 degrees, and Reynolds numbers. This allowed for the identification of shed vortical structures from the maximum chord position, the transitional region where the blade aerofoil blends into a cylindrical joint, and the blade nacelle connection. Analysis of the trailing vorticity interactions between the wake core and freestream shows the vortex meander and diffusion is notably affected by the Reynold’s number. It is hypothesized that the shed vorticity from the blade root region directly influences and exacerbates the nacelle wake expansion in the downstream direction. As the design of inboard blade region form is, by necessity, driven by function rather than aerodynamic optimisation, a study is undertaken for the application of flow control mechanisms to manipulate the observed vortex phenomenon. The designed model allows for the effective investigation of shed vorticity and wake interactions with a focus on the accurate geometry of a root region which is representative of small to medium power commercial HAWTs. The studies undertaken allow for an enhanced understanding of the interplay of shed vortices and their subsequent effect in the near and far wake. This highlights areas of interest within the inboard blade area for the potential use of passive and active flow control devices which contrive to produce a more desirable wake quality in this region.

Keywords: vortex shedding, wake interactions, wind tunnel model, wind turbine

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Authors: Le Kang

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According to the nature of the university, as a free and responsible academic community, USR is based on a different foundation —academic responsibility, so the Pyramid and the IC Model of CSR could not fully explain the most distinguished feature of USR. This paper sought to put forward a new model— Ferris Wheel Model, to illustrate the nature of USR and the process of achievement. The Ferris Wheel Model of USR shows the university creates a balanced, fairness and neutrality systemic structure to afford social responsibilities; that makes the organization could obtain a synergistic effect to achieve more extensive interests of stakeholders and wider social responsibilities.

Keywords: USR, achievement model, ferris wheel model, social responsibilities

Procedia PDF Downloads 722

Authors: Chi-Yuan Huang, Mei-Chuan Kuo, Ching-Yi Hsiao

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In this study, acids with various chain lengths (C₆, C₈, C₁₀ and C₁₂) modified by methane sulfonic acid (MSA) and temperature were used to modify tapioca starch (TPS), then the glycerol (GA) were added into modified starch, to prepare new blends. The mechanical properties, thermal properties and physical properties of blends were studied. This investigation was divided into two parts.  First, the biodegradable materials were used such as starch and glycerol with hexanedioic acid (HA), suberic acid (SBA), sebacic acid (SA), decanedicarboxylic acid (DA) manufacturing with different temperatures (90, 110 and 130 °C). And then, the solution was added into modified starch to prepare the blends by using single-screw extruder. The FT-IR patterns indicated that the characteristic peak of C=O in ester was observed at 1730 cm^-1. It is proved that different chain length acids (C₆, C₈, C₁₀ and C₁₂) reacted with glycerol by esterification and these are used to plasticize blends during extrusion. In addition, the blends would improve the hydrolysis and thermal stability. The water contact angle increased from 43.0° to 64.0°.  Second, the HA (110 °C), SBA (110 °C), SA (110 °C), and DA blends (130 °C) were used in study, because they possessed good mechanical properties, water resistances and thermal stability. On the other hand, the various contents (0, 0.005, 0.010, 0.020 g) of MSA were also used to modify the mechanical properties of blends. We observed that the blends were added to MSA, and then the FT-IR patterns indicated that the C=O ester appeared at 1730 cm^-1. For this reason, the hydrophobic blends were produced. The water contact angle of the MSA blends increased from 55.0° to 71.0°. Although break elongation of the MSA blends reduced from the original 220% to 128%, the stress increased from 2.5 MPa to 5.1 MPa. Therefore, the optimal composition of blends was the DA blend (130 °C) with adding of MSA (0.005 g).

Keywords: chain length acids, methane sulfonic acid, Tapioca starch (TPS), tensile stress

Procedia PDF Downloads 248

Authors: Shishir Lamichhane, Saurav Dulal, Bibek Gautam, Madan Thapa Magar, Indraman Tamrakar

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Renewable energies such as wind turbines and solar photovoltaic have gained significance as a result of global environmental pollution and energy crises. These sources of energy are converted into electrical energy and delivered to end-users through the utility system. As a result of the widespread use of power electronics-based grid-interfacing technologies to accommodate renewable sources of energy, the prevalence of converters has expanded as well. As a result, the power system's rotating inertia is decreasing, endangering the utility grid's stability. The use of Virtual Synchronous Machine (VSM) technology has been proposed to overcome the grid stability problem due to low rotating inertia. The grid-connected inverter used in VSM can be controlled to emulate inertia, which replicates the external features of a synchronous generator. As a result, the rotating inertia is increased to support the power system's stability. A power angle control strategy is proposed in this paper and its model is simulated in MATLAB/Simulink to study the effects of parameter disturbances on the active power and frequency for a VSM. The system consists of a synchronous generator, which is modeled in such a way that the frequency drops to an unacceptable region during transient conditions due to a lack of inertia when VSM is not used. Then, the suggested model incorporating VSM emulates rotating inertia, injecting a controllable amount of energy into the grid during frequency transients to enhance transient stability.

Keywords: damping constant, inertia–constant, ROCOF, transient stability, distributed sources

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Authors: Daniel Fundi Murithi

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Data from economic, social, clinical, and industrial studies are in some way incomplete or incorrect due to censoring. Such data may have adverse effects if used in the estimation problem. We propose the use of Maximum Likelihood Estimation (MLE) under a progressive type-II censoring scheme to remedy this problem. In particular, maximum likelihood estimates (MLEs) for the location (µ) and scale (λ) parameters of two Parameter Rayleigh distribution are realized under a progressive type-II censoring scheme using the Expectation-Maximization (EM) and the Newton-Raphson (NR) algorithms. These algorithms are used comparatively because they iteratively produce satisfactory results in the estimation problem. The progressively type-II censoring scheme is used because it allows the removal of test units before the termination of the experiment. Approximate asymptotic variances and confidence intervals for the location and scale parameters are derived/constructed. The efficiency of EM and the NR algorithms is compared given root mean squared error (RMSE), bias, and the coverage rate. The simulation study showed that in most sets of simulation cases, the estimates obtained using the Expectation-maximization algorithm had small biases, small variances, narrower/small confidence intervals width, and small root of mean squared error compared to those generated via the Newton-Raphson (NR) algorithm. Further, the analysis of a real-life data set (data from simple experimental trials) showed that the Expectation-Maximization (EM) algorithm performs better compared to Newton-Raphson (NR) algorithm in all simulation cases under the progressive type-II censoring scheme.

Keywords: expectation-maximization algorithm, maximum likelihood estimation, Newton-Raphson method, two-parameter Rayleigh distribution, progressive type-II censoring

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Authors: Yasuyuki Takahashi, Hirotaka Shimada, Takao Kanzaki

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A Dual-detector SPECT system is widely by use of myocardial SPECT studies. With 180-degree (180°) acquisition, reconstructed images are distorted in the posterior wall of myocardium due to the lack of sufficient data of posterior projection. We hypothesized that quality of myocardial SPECT images can be improved by the addition of data acquisition of only a few posterior projections to ordinary 180° acquisition. The proposed acquisition method (180° plus acquisition methods) uses the dual-detector SPECT system with a pair of detector arranged in 90° perpendicular. Sampling angle was 5°, and the acquisition range was 180° from 45° right anterior oblique to 45° left posterior oblique. After the acquisition of 180°, the detector moved to additional acquisition position of reverse side once for 2 projections, twice for 4 projections, or 3 times for 6 projections. Since these acquisition methods cannot be done in the present system, actual data acquisition was done by 360° with a sampling angle of 5°, and projection data corresponding to above acquisition position were extracted for reconstruction. We underwent the phantom studies and a clinical study. SPECT images were compared by profile curve analysis and also quantitatively by contrast ratio. The distortion was improved by 180° plus method. Profile curve analysis showed increased of cardiac cavity. Analysis with contrast ratio revealed that SPECT images of the phantoms and the clinical study were improved from 180° acquisition by the present methods. The difference in the contrast was not clearly recognized between 180° plus 2 projections, 180° plus 4 projections, and 180° plus 6 projections. 180° plus 2 projections method may be feasible for myocardial SPECT because distortion of the image and the contrast were improved.

Keywords: 180° plus acquisition method, a few posterior projections, dual-detector SPECT system, myocardial SPECT

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Authors: Saleh Alzahrani

Abstract:

The studies in the field of International Comparative Education in the Arabic world and the middle east are scarcity. However, some International Comparative Education Researchers and post graduates face a challenge concerning of a selection of a distinguished study to improve their national education system. It requires a considerable effort. According to that, the matrix of scientific research in comparative and international education is designed to help specialists, researchers and graduate students in generating a variety of research ideas in a short time in this field. The matrix is built by using content analysis method of comparative education research published in the Arab journals from 1980 to 2017. Then, qualitative input with the in-depth focus analysis tool is utilized according to the root theory. The matrix consists of two axes; vertical (X) and horizontal (Y). The number of fields in the vertical axis are 6 domains, including 105 variables. The horizontal axis is two fields which are pre-university education that incorporate educational stages and contemporary formulations including (23) variables. The second field is the university education in its public universities and contemporary formulas including (15) variables. The researcher can access topics, ideas and research points through the matrix of scientific research in comparative and international education by selecting of any subject on the vertical axis (X) from (1) to (105) and selecting of any subject on the horizontal axis (Y) from (B) to (U). The cell where the axes intersect with the chosen fields can generate an idea or a research point conveniently and easily through the words that have been monitored by the user. These steps can be repeated to generate new ideas and research points. Many graduate researchers have been trained on using of this matrix which gave them more potential to generate an appropriate study serving the national education.

Keywords: content analysis method, comparative education, international education, matrix, root theory

Procedia PDF Downloads 132

Authors: Timea I. Hajnal-Jafari, Simonida S. Đurić, Dragana R. Stamenov

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Microbial inoculants from the group of symbiotic-nitrogen-fixing rhizobia are well known and widely used in production of legumes. On the other hand, nonsymbiotic plant growth promoting rhizobacteria (PGPR) are not commonly used in practice. The objective of this study was to examine the effects of soybean inoculation with symbiotic and nonsymbiotic bacteria on plant growth and seed yield of soybean. Microbiological activity in rhizospheric soil was also determined. The experiment was set up using a randomized block system in filed conditions with the following treatments: control-no inoculation; treatment 1-Bradyrhizobium japonicum; treatment 2-Azotobacter sp.; treatment 3-Bacillus sp..In the flowering stage of growth (FS) the number of nodules per plant (NPP), root length (RL), plant height (PH) and weight (PW) were measured. The number of pod per plant (PPP), number of seeds per pod (SPP) and seed weight per plant (SWP) were recorded at the end of vegetation period (EV). Microbiological analyses of soil included the determination of total number of bacteria (TNB), number of fungi (FNG), actinomycetes (ACT) and azotobacters (AZB) as well as the activity of the dehydrogenase enzyme (DHA). The results showed that bacterial inoculation led to the formation of root nodules regardless of the treatments with statistically no significant difference. Strong nodulation was also present in control treatment. RL and PH were positively influenced by inoculation with Azotobacter sp. and Bacillus sp., respectively. Statistical analyses of the number of PPP, SPP, and SWP showed no significant differences among investigated treatments. High average number of microorganisms were determined in all treatments. Most abundant were TNB (log No 8,010) and ACT (log No 6,055) than FNG and AZB with log No 4,867 and log No 4,025, respectively. The highest DHA activity was measured in the FS of soybean in treatment 3. The application of nonsymbiotic bacteria in soybean production can alleviate initial plant growth and help the plant to better overcome different stress conditions caused by abiotic and biotic factors.

Keywords: bacteria, inoculation, soybean, microbial activity

Procedia PDF Downloads 151

Authors: Shashank Gahlaut, Chandrashekhar Sharan, J. P. Singh

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Increasing incidence of antibiotic-resistant bacteria is a big concern for the treatment of pathogenic diseases. The effect of treatment of patients with antibiotics often leads to the evolution of antibiotic resistance in the pathogens. The detection of antibiotic or antimicrobial resistant bacteria (microbes) is quite essential as it is becoming one of the big threats globally. Here we propose a novel technique to tackle this problem. We are taking a step forward to prevent the infections and diseases due to drug resistant microbes. This detection is based on some unique features of silver (a noble metal) nanorods (AgNRs) which are fabricated by a physical deposition method called thermal glancing angle deposition (GLAD). Silver nanorods are found to be highly sensitive and selective for hydrogen sulfide (H2S) gas. Color and water wetting (contact angle) of AgNRs are two parameters what are effected in the presence of this gas. H₂S is one of the major gaseous products evolved in the bacterial metabolic process. It is also known as gasotransmitter that transmits some biological singles in living systems. Nitric Oxide (NO) and Carbon mono oxide (CO) are two another members of this family. Orlowski (1895) observed the emission of H₂S by the bacteria for the first time. Most of the microorganism produce these gases. Here we are focusing on H₂S gas evolution to determine live/dead and antibiotic-resistant bacteria. AgNRs array has been used for the detection of H₂S from micro-organisms. A mobile app is also developed to make it easy, portable, user-friendly, and cost-effective.

Keywords: antibiotic resistance, hydrogen sulfide, live and dead bacteria, mobile app

Procedia PDF Downloads 143

Authors: Andre F. A. Cyrino

Abstract:

Knowing that the technological advance is the focus on the efficient extraction of energy from wind, and therefore in the design of wind turbine structures, this work aims the study of the fluid-structure interaction of an idealized wind turbine. The blade was studied as a beam attached to a cylindrical Hub with rotation axis pointing the air flow that passes through the rotor. Using the calculus of variations and the finite difference method the blade will be simulated by a discrete number of nodes and the aerodynamic forces were evaluated. The study presented here was written on Matlab and performs a numeric simulation of a simplified model of windmill containing a Hub and three blades modeled as Euler-Bernoulli beams for small strains and under the constant and uniform wind. The mathematical approach is done by Hamilton’s Extended Principle with the aerodynamic loads applied on the nodes considering the local relative wind speed, angle of attack and aerodynamic lift and drag coefficients. Due to the wide range of angles of attack, a wind turbine blade operates, the airfoil used on the model was NREL SERI S809 which allowed obtaining equations for Cl and Cd as functions of the angle of attack, based on a NASA study. Tridimensional flow effects were no taken in part, as well as torsion of the beam, which only bends. The results showed the dynamic response of the system in terms of displacement and rotational speed as the turbine reached the final speed. Although the results were not compared to real windmills or more complete models, the resulting values were consistent with the size of the system and wind speed.

Keywords: blade aerodynamics, fluid–structure interaction, wind turbine aerodynamics, wind turbine blade

Procedia PDF Downloads 266

Authors: Fadwa Chtioui

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Vital Pulp Therapy (VPT) is nowadays challenging the deep-rooted dogma of root canal treatment, being the only therapeutic option for permanent teeth diagnosed with irreversible pulpitis or carious pulp exposure. Histologic and clinical research has shown that compromised dental pulp can be treated without the full removal or excavation of all healthy pulp, and the outcome of the partial or full pulpotomy followed by a Tricalcium-Silicate-based dressing seems to show promising results in maintaining pulp vitality and preserving affected teeth in the long term. By reviewing recent advances in the techniques of VPT and their clinical effectiveness and safety in permanent teeth with irreversible Pulpitis, this work provides a new understanding of pulp pathophysiology and defense mechanisms and will reform dental practitioners' decision-making in treating irreversible pulpits from root canal therapy to vital pulp therapy by taking advantage of the biological effects of Tricalcium Silicate materials. Biography of presenting author: Fadwa Chitoui graduated from the school of Dental Medicine of Monastir, Tunisia, in 2015. After getting her DDS degree with honors, she earned her Postgraduate master's Degree in Endodontics and Restorative Dentistry from her Faculty. Since 2021, she has Started her own private and specialized practice based in the capital Tunis. She enjoys the sphere of associative life, worked with national and international associations, and got engaged in scientific dental research, whereby she tailored her passion for her field of specialty towards broadening her knowledge and ambitions, holding conferences and workshops nationally and internationally and publishing scientific articles in several journals.

Keywords: irreversible pulpitis, permanenet teeth, vital pulp therapy, pulpotomy

Procedia PDF Downloads 66

Authors: Osk Dagsdottir

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Background—Gait classifying allows clinicians to differentiate gait patterns into clinically important categories that help in clinical decision making. Reliable comparison of gait data between normal and patients requires knowledge of the gait parameters of normal children's specific age group. However, there is still a lack of the gait database for normal children of different ages. Objectives—This study aims to investigate the kinematics of the lower limb joints during gait for normal children in different age groups. Methods—Fifty-three normal children (34 boys, 19 girls) were recruited in this study. All the children were aged between 5 to 16 years old. Age groups were defined as three types: young child aged (5-7), child (8-11), and adolescent (12-16). When a participant agreed to take part in the project, their parents signed a consent form. Vicon® motion capture system was used to collect gait data. Participants were asked to walk at their comfortable speed along a 10-meter walkway. Each participant walked up to 20 trials. Three good trials were analyzed using the Vicon Plug-in-Gait model to obtain parameters of the gait, e.g., walking speed, cadence, stride length, and joint parameters, e.g., joint angle, force, moments, etc. Moreover, each gait cycle was divided into 8 phases. The range of motion (ROM) angle of pelvis, hip, knee, and ankle joints in three planes of both limbs were calculated using an in-house program. Results—The temporal-spatial variables of three age groups of normal children were compared between each other; it was found that there was a significant difference (p < 0.05) between the groups. The step length and walking speed were gradually increasing from young child to adolescent, while cadence was gradually decreasing from young child to adolescent group. The mean and standard deviation (SD) of the step length of young child, child and adolescent groups were 0.502 ± 0.067 m, 0.566 ± 0.061 m and 0.672 ± 0.053 m, respectively. The mean and SD of the cadence of the young child, child and adolescent groups were 140.11±15.79 step/min, 129±11.84 step/min, and a 115.96±6.47 step/min, respectively. Moreover, it was observed that there were significant differences in kinematic parameters, either whole gait cycle or each phase. For example, RoM of knee angle in the sagittal plane in the whole cycle of young child group is (65.03±0.52 deg) larger than child group (63.47±0.47 deg). Conclusion—Our result showed that there are significant differences between each age group in the gait phases and thus children walking performance changes with ages. Therefore, it is important for the clinician to consider the age group when analyzing the patients with lower limb disorders before any clinical treatment.

Keywords: action research, creative learning, mathematics education, professional development

Procedia PDF Downloads 107

Authors: Muhamad Sani Buang, Shahrul Azam Abdullah, Juri Saedon

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There is not much effective guideline on development of design parameters selection on springback for advanced high strength steel sheet metal in U-channel process during cold forming process. This paper presents the development of predictive model for springback in U-channel process on advanced high strength steel sheet employing Response Surface Methodology (RSM). The experimental was performed on dual phase steel sheet, DP590 in U-channel forming process while design of experiment (DoE) approach was used to investigates the effects of four factors namely blank holder force (BHF), clearance (C) and punch travel (Tp) and rolling direction (R) were used as input parameters using two level values by applying Full Factorial design (24). From a statistical analysis of variant (ANOVA), result showed that blank holder force (BHF), clearance (C) and punch travel (Tp) displayed significant effect on springback of flange angle (β2) and wall opening angle (β1), while rolling direction (R) factor is insignificant. The significant parameters are optimized in order to reduce the springback behavior using Central Composite Design (CCD) in RSM and the optimum parameters were determined. A regression model for springback was developed. The effect of individual parameters and their response was also evaluated. The results obtained from optimum model are in agreement with the experimental values

Keywords: advance high strength steel, u-channel process, springback, design of experiment, optimization, response surface methodology (rsm)

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Authors: Hady Atef Labib

Abstract:

Pediatric cardiac rehabilitation has the potential to benefit many children with congenital heart defects (CHD). Instead of excellent surgical results most of children usually present with a depression of physical condition so early rehabilitation program is recommended to avoid that decline in physical tolerance and prevent any post surgical complications. Unfortunately, the limited experience with and availability of these programs has caused the benefits of cardiac rehabilitation to be unavailable to most children with CHD. Therefore, it is recommended to study that field in more detail and apply it on wider scale.

Keywords: pediatric cardiac rehabilitation, congenital heart disease, quality of life, pediatric

Procedia PDF Downloads 376