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Novel Flexible FBAR on PET Substrate
No full textA novel flexible Film Bulk Acoustic Wave Resonators (FBARs) based on ZnO/PET structure was fabricated without back-etch. The PET layer is applied as acoustic reflector and substrate of FBAR. It has 1.14GHz parallel resonant frequency, 1.229GHz series resonant frequency and about 150 Q factors. The FBARs acoustic impedance is improved by using harden metal Au instead of AI as the bottom electrodes. The ZnO/PET structure FBAR is also simulated by COSMOL to confirm its working mechanism
Assessing the impact of private agriculture extension system in achieving food security in Malawi : a case of Chiwamba extension planning area
No full textThe notion that private agricultural extension systems supplement the efforts of Government of Malawi to contribute to food security cannot be denied. The agriculture sector has experienced challenges,(due to natural and man-made causes), to improve agricultural productivity levels for farmers, hence introduction of demand driven approaches through involvement of different actors which include the non state sector, was the possible way to respond to the challenges.The study assessed the impact of private agricultural extension system to contribute to achievement of food security. The study looked at the performance of both public and private agricultural extension system and contributions made to support farmers in achieving food security at household level. Different studies assessed the coordination and financing role of Government since the establishment of the policy in 2000. However, limited studies have been conducted to assess the impact of private agricultural extension system in contributing to food security The objectives of the study were to review the current private extension delivery system, assess how food is achieved at household level and how this is translated to national level and also looked at influencing factors for effectiveness of private extension service for achievement of food security and recommend ways to sustain food security demands. In-depth interviews with households helped to collect quantitative information while Focus Group Discussion with men and women (cluster leaders and lead farmers) assisted to obtain qualitative information together with professional staff interviews.The findings of the study indicated that there are attempts to achieve food security despite the challenges which occur during implementation mostly were related to natural causes. The research identified a number of interventions which farmers were able to mentions as part of livelihood diversification example good agricultural practices, coping mechanisms to shocks, access to credit and information accompanied by training. Activities towards empowerment of farmers was one success registered in the study which was through the trainings and information provided. This empowerment of farmers and coordination of extension services was also one aspect which was developing and could be improved if programmes and existing structures are well utilised and maintained for extension messages development, delivery and resource mobilisation. It is imperative for private extension to ensure that partnerships are developed that can be self sustaining and implemented through public -private partnership which respond to farmers needs in terms of resource sharing, farmer organisation and mobilisation of resources for sustaining extension development.Further research can be done on development of a domesticated framework for pluralistic approach in attainment of food security using the existing models like One Village One Product which is spread nationwide and can draw conclusions and recommendations which can best respond to farmers needs as Malawi is refocusing its agriculture sector towards extension
Interaction of a non-aqueous solvent system on bamboo, cotton, polyester and their blends : the effect on abrasive wear resistance.
No full textThis article investigates the use of Trichloroacetic acid-Methylene chloride (TCAMC) solvent system with a view to study the abrasive wear resistance of bamboo, cotton, organic cotton, polyester (PES), cotton/bamboo and polyester/cotton blended woven fabrics. The fabrics were treated with different concentrations of 1%, 5% and 10% of TCAMC for 5, 30 and 60 mins at room temperature. Martindale Abrasion Tester was employed to test the abrasive wear resistance of fabrics. The weight loss of fabrics was checked after every 1000 abrasive cycles. The results suggest that the bamboo fabric, without TCAMC treatment, possesses an abrasive wear resistance that is comparable to that of organic cotton fabric. However, cotton/bamboo blend fabric was found to have enhanced abrasion wear resistance than that of 100% bamboo fabric. The results also indicate that the TCAMC treatment enhanced the abrasion wear resistance of 100% bamboo and 100% organic cotton fabrics. The treatment does not influence the wear resistance of 100% cotton and its blends. The abrasive wear resistance of untreated polyester (PES) fabric was tested and compared with cellulosics and it was found that PES possessed higher abrasive wear resistance. However, the abrasive wear resistance of TCAMC treated PES decreased considerably
Influence of plasma pre-treatment of polytetrafluoroethylene(PTFE) micropowders on the mechanical and tribological performance of Polyethersulfone (PESU) – PTFE composites
No full textFast and facile preparation of CTAB based gels and their applications in Au and Ag nanoparticles synthesis.
No full textSemester of Code: Piloting Virtual Placements for Informatics across Europe
No full textVALS (Virtual Alliances for Learning Society) European Project intends to build knowledge partnerships between European Higher Education Institutions and Business stakeholders across the World to collaborate on resolving authentic business problems through Open Innovation and Open Source Software. To conduct these knowledge partnerships, the VALS project leverages the virtual placements, in which students from all European countries can be involved in the resolution of real business problems, developing by this way professional skills, and other business-related attitudes that will help them to enhance their (future) professional career. These virtual placements result in the Semester of Code, which is a set of practices, methods and processes for creating and managing real virtual placements. Following these ideas, this paper is focused in the description of how is designed this Semester of Code, how the VALS partners have developed different tools, guidelines and processes to manage and track the virtual placements and how are performed this set of tools and guidelines in order to achieve the success in the pilot tests of the Semester of Code and its virtual placements
Evaluation of serious games: a holistic approach
No full textDigital games constitute a major emerging technology that is expected to enter mainstream educational use within a few years. The highly engaging and motivating character of such games bears great potential to support immersive, meaningful, and situated learning experiences. To seize this potential, meaningful quality and impact measurements are indispensible. Although there is a growing body of evidence on the efficacy of games for learning, evaluation is often poorly designed, incomplete, biased, if not entirely absent. Well-designed evaluations demonstrating the educational effect as well as the return on investment of serious games may foster broader adoption by educational institutions and training providers, and support the development of the serious game industry. The European project RAGE introduces a comprehensive and multi-perspective framework for serious game evaluation, which is presented in this paper
Finite element simulation of carbon fibre-reinforced composite laminates subjected to low velocity impact using damage induced static load-deflection methodology
No full textThis work is concerned with the prediction of low velocity impact damage resistance of carbon fibre-reinforced laminated composite laminates. Pre-assumed damage induced laminates were simulated to correlate damage corresponding to impactor nose profiles. Majority of the existing studies conducted on the topic are experimental, based on three-dimensional stresses and failure theories that cannot readily predict ply level impact damage. Hence efficient computational models are required. The present study was conducted to efficiently predict ply level impact response of composite laminates. Static load-deflection based computational model was developed in the commercial software ABAQUS (TM). Eight, 16, and 24 ply laminates impacted by point, small, medium, and flat nose impactors were considered with emphasis on flat nose impacts. Loading areas under the impactor nose profiles were partitioned to investigate effects from variations in applied loading. Pre-assumed damage zones consisting of degraded material properties equivalent to the impactor nose profiles were inserted across thickness of the laminates to predict ply-by-ply damage. Impactor nose profiles and pre-assumed damage zones (size, type, and location) were correlated to the simulation produced deflection quantities to predict the ply level damage. Selected results were compared against the data available in the literature and also against the intra-simulation results and found in good agreement. (C) 2015 Elsevier Ltd. All rights reserved
Humidity effects on resolution and sensitivity of UV-FAIMS in VOCs detection
No full textHumidity is a key environmental parameter for VOCs detection technology. A study of the effects of humidity on both resolution and sensitivity of UV-FAIMS was performed at ambient temperature and pressure. This study was based on the detection and analysis of the differences in spectra (height, position and shape) and the a function of VOCs under different degrees of humidity. A total of three types of VOCs (ketones, alcohols and aromatics) were chosen as detection samples and a selfdeveloped UV-FAIMS as a measurement instrument. The results show that sensitivity is inversely proportional to humidity for all VOCs. In addition, the resolution-humidity relationship exhibits strong dependence on the polarity of the sample ions. As relative humidity increased from 0% to 100%, the sensitivity of ketones, alcohols and aromatics was reduced by 30.9-73.0%, 40.3-64.3% and 75.1-91.6%, respectively. However, increasing humidity significantly enhanced the resolution of ketones and alcohols in the ranges of 1.82-11.82 times and 1.23-6.69 times, respectively, and hardly affected that of aromatics. Consequently, the appropriate humidity of carrier gas is of great importance in the use of UV-FAIMS