1,727 research outputs found
INNOVATIVE CERAMIC MATERIALS AND PROCESSES FOR AERONAUTIC APPLICATIONS
Get PDFIn the field of aerospace, aircrafts are the most dominant element with other spacecrafts and research satellites finding a limited usage. All the space vehicles are run by the highly efficient engines to make them escape the gravity in case of spacecraft or enable them to carry heavy loads and move quickly to the long destination as achieved by the civil and military planes. To achieve the excellence in transportation in the space, air vehicles are fitted with the engines (rocket or jet engines), these are termed as the power houses and are operated at extremely high temperature and pressure. Such a high temperature achievement and sustainment over the passage of time has put the challenges to the manufacturers and material producers. Spacecrafts and other research crafts which are specifically designed to achieve supersonic flights use special type of non-air breathing engines (rocket engine or scramjet/ramjet) and materials and comprise only up to 10% of the aeronautical industry. All other planes used by the airliners or being used as military planes rely on the air-breathing engines (jet engines). Depending upon the function and role of a plane these jet engines have different modifications but the operating unit and principle of all these engines remain same and is a variant of gas generator. Common goal of achieving the maximum fuel efficiency (thermal efficiency) in all the planes still remain same. Achievement of high thermal efficiency led to the development of materials and new methods to extract the maximum possible effectiveness of the materials. Simultaneously, new techniques also emerged to boost the overall operation. One such milestone was the development of superalloys and evolve of the process to fabricate superalloyed blades from equiaxed to single crystal. And introduction of cooling channels and thermal barrier coatings has carried this to limits of the current systems. With the metals and existing technology reaching the limit, focus is placed on the development of ceramic materials. Most of the technical (high temperature) ceramics are brittle and difficult to fabricate, Si3N4 one among this class is overlapping with metals in terms of toughness but production of this material into useful components is challenging. There are some derivatives of Si3N4 which are easy to produce (develop) into components but their development is limited to few special ceramic processing techniques. These derivatives are α-Sialon and β-Sialon later is easy to fabricate and develop into the components but is very soft, the former is hard and strong and impossible to be synthesized without the use of hot isostatic pressing (HIP), hot pressing and spark plasma sintering (SPS). All of these methods limit the size and geometry of the object to be produced. Machining of these hard materials at cost of diamond to make useful shapes is another restriction; additionally highly machined components may get notches and other fabrication defects which limit the mechanical properties. Production of Si3N4 based materials, Sialons, using the colloidal processing and pressure less consolidation (sintering) technique has been the challenge. Composition of the pure α-Sialon material was modified with another material, aluminosilicate (β-Sialon former) and this system could be sintered without applying pressure. Modification of this system (material-method) as influenced by the other useful additives like MgO, Spinel and Ce2O3 was also observed. Hence a new material system capable to be processed by shaping and forming methods linked to colloidal processing was designe
Are people willing to pay to move away from coal-fired plants?
No full textPhasing out coal-fired power is key to mitigate climate change. However, fast-growing nations such as India and China still invest heavily in coal as an energy source. Popular pressure could revert this situation, but it is not clear whether those who reside near coal plants are aware of their negative consequences. Azhar Hussain investigates how people value air quality and their willingness to pay to move away from coal-fired power
SHERPA Ref (and so can you!)
Get PDFThis 7-minute presentation by Adam Field, Jane Anders and Azhar Hussain of Jisc was given at RepoFringe 2016 on Monday 1st of August as part of the 24x7 session on 'The Nuts and Bolts of Open'. It describes how the SHERPA Ref may be used to help evaluate whether a publication may be submitted for the Research Excellence Framework
Kamus al-Azhar: versi Melayu-Arab-Inggeris = Malay-Arab-English version
Get PDFKamus AL-Azhar telah disusun bagi memudahkan pelajar dalam membuat rujukan dan menambahkan pengetahuan. Proses penyusunan kamus ini memerlukan pengalaman, kegigihan dan kepakaran didalam tiga bidang bahasa tersebut. Selain itu usaha dan semangat kearah penyusunan kamus ini timbul kerana kami melihat betapa pentingnya ketiga-tiga bahasa ini. Dengan adanya kamus ini Bahasa Melayu dan Bahasa Arab dapat dimartabatkan dimata dunia
AN EMPIRICAL ANALYSIS OF AFTER SALES SERVICE AND CUSTOMER SATISFACTION
No full textIn today’s ever changing competitive environment, business cannot survive unless they satisfy their customers. The delivery of after sales service by a company is critical in satisfying customer needs and perceptions. In order to have quality after sales service a proper delivery system
has to be in place. This is an empirical study on after sales
quality of Pakistan’s automotive battery manufacturer. The research measured the quality of service in Atlas Battery, selling product with the brand name of AGS by using the Servqual method. The data was collected using an instrument from previous study to study the impact of quality
of after sales services on customer satisfaction. The main variables effecting customer satisfaction are product quality and social responsibility. The results reveal that customer satisfaction increases with better service delivery
- …
