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This study aims to simulate Hunter turbine in Computer Forensic Examiner (CFX) environment dynamically. For this purpose, the turbine is designed in desired dimensions and simulated in ANSYS software under a specific fluid flow rate. The obtained values were then compared with previous studies for different values of angles (θ and α). The amount of validation error were obtained.

In this research, at first, the study of fluid flow and then the examination of that in the tidal turbine and identifying the turbines used for tidal energy extraction are performed. For this purpose, the equations governing flow and turbine are thoroughly investigated, and the computational fluid dynamic simulation is done after numerical modeling of Hunter turbine in a CFX environment.

The failure results showed; 11.25% for the blades to fully open, 2.5% for blades to start, and 2.2% for blades to close completely. Also, results obtained from three flow coefficients, 0.36, 0.44 and 0.46, are validated by experimental data that were in high-grade agreement, and the failure value coefficients of (0.44 and 0.46) equal (0.013 and 0.014), respectively.

In this research, at first, the geometry of the Hunter turbine is discussed. Then, the model of the turbine is designed with SolidWorks software. An essential feature of SolidWorks software, which was sorely needed in this project, is the possibility of mechanical clamping of the blades. The validation is performed by comparing the results with previous studies to show the simulation accuracy. This research’s overall objective is the dynamical simulation of Hunter turbine with the CFX. The turbine was then designed to desired dimensions and simulated in the ANSYS software at a specified fluid flow rate and verified, which had not been done so far.

Although music education has been proven to benefit students, music programs are often cut when public school funding is reduced. The cost of instruments is a significant financial burden on music programs, which restricts student access to high-quality instruments that would benefit their learning. Therefore, this paper aims to develop additively manufactured, polylactic acid (PLA) claves that could reproduce the sound of wooden claves and be printed by students in schools at a reduced cost to promote equal access to music education regardless of a school’s financial status.

This study developed a dual approach for analyzing clave vibration using mathematical analysis in MATLAB and SolidWorks finite element frequency simulation to predict the natural frequencies of 15 claves with varying geometries. To evaluate the performance of both models, the authors obtained natural frequencies experimentally by recording the claves and analyzing the resulting frequency spectra. The authors considered the possible effects of damping and determined the effective damping required in both models through comparison with experimental results.

Results indicate that PLA claves cannot easily be made to replicate the high pitch of rosewood claves while maintaining typical clave dimensions. However, PLA claves could still be suitable in instances where matching pitch is not a primary concern or improved durability is desired. The SolidWorks simulation approach could accurately predict clave pitch for all varieties of clave, whereas the mathematical approach was only accurate in predicting pitch for the filled claves.

In this work, the authors attempted to create an analytical process for simple percussion instrument design, which is typically done with trial-and-error methods. Instead, the authors developed a two-pronged approach in which experimental results were compared to results obtained both mathematically and from a finite element simulation. Additionally, we limited the materials and equipment used to those that would be available in a school setting so that the clave prototypes could be reproduced by public school students, the population this research is intended to serve.

The development of robust control algorithms for the position, velocity and trajectory control of unmanned underwater vehicles (UUVs) depends on the accuracy of their mathematical models. Accuracy of the model is determined by precise estimation of the UUV hydrodynamic parameters. The purpose of this study is to determine the hydrodynamic forces and moments acting on an underwater vehicle with complex body geometry and moving at low speeds and to achieve the accurate coefficients associated with them.

A three-dimensional (3D) computer-aided design (CAD) model of UUV is designed with one-to-one dimensions. 3D fluid flow simulations are conducted using computational fluid dynamics (CFD) software programme in the solution of Navier Stokes equations for laminar and turbulent flow analysis. The coefficients depending on the hydrodynamic forces and moments are determined by the external flow analysis using the CFD programme. The Flow Simulation k-ε turbulence model is used for the transition from laminar flow to turbulent flow. Hydrodynamic properties such as lift and drag coefficients and roll and yaw moment coefficients are calculated. The parameters are compared with the coefficient values found by experimental methods.

Although the modular type UUV has a complex body geometry, the comparative results of the experiments and simulations confirm that the defined model parameters are accurate and close to the actual experimental values. In the proposed k-ε method, the percentage error in the estimation of drag and lifting coefficients is decreased to 4.2% and 8.39%, respectively.

The model coefficients determined in this study can be used in high-level control simulations which leads to the development of robust real-time controllers for complex-shaped modular UUVs.

The Lucky Fin UUV with 4 degrees of freedom is a specific design and its CAD model is first extracted. Verification of simulation results by experiments is generally less referenced in studies. However, it provides more precise parameter identification of the model. Proposed study offers a simple and low-cost experimental measurement method for verification of the hydrodynamic parameters. The extracted model and coefficients are worthwhile references for the analysis of modular type UUVs.

The focus of this study is to explore the perceptions of motivation for further training and empowerment in future jobs of participants in different training activities under a public programme implemented in Catalonia (Spain), which delivers continuing vocational education and training (CVET) courses for unemployed and for active workers alike.

The authors used a mixed methodology approach to study the motivation and empowerment perceived in the sample of participants. From an online survey of 281 participants in a CVET programme from the network of public centres that implement the programme in Catalonia, the authors analysed quantitatively the responses and then applied an inductive analysis for the responses related to motivation and empowerment perceived by the participants.

Results show that the participation in this CVET programme has influenced positively the perception of motivation of the majority of participants to enrol in further education or training (80.43%), while at the other end of the spectrum, 18.86% of the participants reported low or no motivation to participate in further education or training. Regarding the empowerment towards their future workplace, 59.43% of participants perceived a high empowerment, while 37.37% reported feeling low-empowered or disempowered.

This is one of the few studies that takes interest in studying a CVET public programme and its potential impact in generating perceptions of motivation for further education or training and empowerment in the participants. Moreover, its implementation was possible due to the collaboration of the public administration, which disseminated the survey to their students.

The purpose of this paper is to report the development and implementation of a Remotely Accessible Rapid Prototyping Laboratory (RRPL) established at Tennessee Tech University. Instructional materials and best practices are also reported.

The Rapid Prototyping (RP) Laboratory reported in this paper was established in Fall 2003 and funded by a National Science Foundation (NSF) grant and Tennessee Tech University (TTU) matching funds. Since that time, over a thousand high school students and students studying computer aided design and manufacturing at Tennessee Tech University have practiced with the RP technology. In order to further extend a remote access capability to this current laboratory and let more engineering and technology students learn this technology via online access tools and resources, a new NSF grant was awarded in late 2006. Since that time, the remote RP laboratory development has been practiced by over 50 higher education institutions. In early 2009, another NSF grant was awarded to allow Metro Nashville Public School students to practice in the remote RP laboratory and choose Science, Technology, Engineering and Math (STEM) career academies for their future profession pathways. This paper will report the development and implementation of a remotely accessible laboratory for RP practices. The topics highlighted are the design of the laboratory, its remote delivery implementation to P16 (integrated system of education stretching from early childhood through a four‐year college degree) education systems and web‐based access statistics collected from counting resources.

Although on‐ground RP systems are commonly practiced by many institutions; such a unique application as reported in this paper was a pioneering effort, since RRPL was used by many educational institutions as part of their curricular practices.

The paper shows how the online accessible laboratory and its instructional materials provide a number of unique features in cost saving and sharing of the RP resources.

Blended learning is an emerging trend across many educational settings, adopting the purposeful integration of traditional face-to-face and online teaching to establishing an engaging learning experience for the students. Blended learning provides an ideal platform for the implementation of reusable learning objects (RLOs) as a pedagogical tool to support classroom instruction.

This study had conducted a quasi-experiment followed by semi-structured interviews to determine if a blended learning approach using RLOs can enhance students’ learning in an undergraduate engineering computer-aided design (CAD) module. This study involved learners studying engineering in two different academic years.

Students from the first year were taught using traditional face-to-face teaching approach. The cohort of students from the subsequent year adopted a blended learning approach: face to face and access to a series of RLOs. The analysis revealed statistical evidence that the use of blended learning had a significant impact on the students' end of term exam grades in the CAD module in comparison to the students who undertook traditional face-to-face teaching approach. The qualitative findings highlighted the positive impact of RLOs on students’ learning behaviour, engagement and knowledge retention.

This study provided empirical evidence of the benefits of using RLOs as a blended learning tool in engineering domain. From a theoretical perspective, the findings highlighted the importance of good instructional design and sound theoretical underpinning of the pedagogical strategy. From a practical point of view, this study informed academics on how to improve learner's academic achievement using RLOs.

The purpose of this paper is to elucidate the effect of part thickness and build orientation upon the type and magnitude of distortion in material jetting processes.

Specimens with high (10:1) aspect ratio were printed in two orientations (XY and YX) and three thickness values (1, 3 and 6 mm) and scanned with a white-light profilometer to quantify distortion.

The results of this paper indicate that 1-mm thick specimens always distorted following a wavy edge type, while thicker specimens (3- and 6-mm) always distorted following a reverse coil set. The factor thickness, when measured with the indices height of the highest peak (H) and profile radius (R), was shown to be statistically significant, with 3-mm specimens experiencing distortions of 57 and 51 per cent, respectively, more severe than those in 6-mm specimens. The thickness effect is attributed to the percentage of build layers that receive maximum energy exposure (61-72 per cent in 1-mm, 87-91 per cent in 3-mm and 93-95 per cent in 6-mm specimens). With respect to the thinner 1-mm specimens, the factor orientation was found to be statistically significant with distortion 114 per cent less severe in the YX orientation when measured by the H index.

This paper provides the first known description of build orientation and part thickness effects on dimensional distortion as a pervasive consequence of the curing process in photopolymerization and explores one of the most common defects encountered in additive manufacturing. In addition to the characterization of the type and magnitude of distortion, the contributions of this paper also include establishing the foundation for design guidelines aiming at minimizing distortion in material jetting.

Solid freeform fabrication (SFF) has the potential to revolutionize manufacturing, even to allow individuals to invent, customize, and manufacture goods cost‐effectively in their own homes. Commercial freeform fabrication systems – while successful in industrial settings – are costly, proprietary, and work with few, expensive, and proprietary materials, limiting the growth and advancement of the technology. The open‐source Fab@Home Project has been created to promote SFF technology by placing it in the hands of hobbyists, inventors, and artists in a form which is simple, cheap, and without restrictions on experimentation. This paper aims to examine this.

A simple, low‐cost, user modifiable freeform fabrication system has been designed, called the Fab@Home Model 1, and the designs, documentation, software, and source code have been published on a user‐editable “wiki” web site under the open‐source BSD License. Six systems have been built, and three of them given away to interested users in return for feedback on the system and contributions to the web site.

The Fab@Home Model 1 can build objects comprising multiple materials, with sub‐millimeter‐scale features, and overall dimensions larger than 20 cm. In its first six months of operation, the project has received more than 13 million web site hits, and media coverage by several international news and technology magazines, web sites, and programs. Model 1s are being used in a university engineering course, a Model 1 will be included in an exhibit on the history of plastics at the Science Museum London, UK, and kits can now be purchased commercially.

The ease of construction and operation of the Model 1 has not been well tested. The materials cost for construction (US$2,300) has prevented some interested people from building systems of their own.

The energetic public response to the Fab@Home project confirms the broad appeal of personal freeform fabrication technology. The diversity of interests and desired applications expressed by the public suggests that the open‐source approach to accelerating the expansion of SFF technology embodied in the Fab@Home project may well be successful.

Fab@Home is unique in its goal of popularizing and advancing SFF technology for its own sake. The RepRap project in the UK predates Fab@Home, but aims to build machines which can make most of their own parts. The two projects are complementary in many respects, and fruitful exchanges of ideas and designs between them are expected.

A methodology for designing and printing three-dimensional (3D) objects with specified printing-direction using fused deposition modeling (FDM), which was proposed by a previous paper, enables the expression of natural directions, such as hair, fabric or other directed textures, in modeled objects. This paper aims to enhance this methodology for creating various shapes of generative visual objects with several specialized attributes.

The proposed enhancement consists of two new methods and a new technique. The first is a method for “deformation”. It enables deforming simple 3D models to create varieties of shapes much more easily in generative design processes. The second is the spiral/helical printing method. The print direction (filament direction) of each part of a printed object is made consistent by this method, and it also enables seamless printing results and enables low-angle overhang. The third, i.e. the light-reflection control technique, controls the properties of filament while printing with transparent polylactic acid. It enables the printed objects to reflect light brilliantly.

The proposed methods and technique were implemented in a Python library and evaluated by printing various shapes, and it is confirmed that they work well, and objects with attractive attributes, such as the brilliance, can be created.

The methods and technique proposed in this paper are not well-suited to industrial prototyping or manufacturing that require strength or intensity.

The techniques proposed in this paper are suited for generatively producing various a small number of products with artistic or visual properties.

This paper proposes a completely different methodology for 3D printing than the conventional computer-aided design (CAD)-based methodology and enables products that cannot be created by conventional methods.