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Rapid Applications Development Techniques : A Critical Review
Riffat Naz,M. N. A. Khan 보안공학연구지원센터 2015 International Journal of Software Engineering and Vol.9 No.11
There are different product maintenance and support techniques. These previous techniques do not solve user/clients bugs, issues and enhancements effectively and efficiently. Scrum is being used now a day as a quick, flexible and holistic methodology to develop software. In Scrum projects there is the much customer involvement is included which help to develop a user oriented product. Users can change their requirements in Scrum. Many techniques have been proposed for product maintenance and support. However, in this paper, there have been a detailed literature review of existing product maintenance techniques and also presented a new proposed model and technique for the product maintenance by using Scrum methodology. This Scrum based model for maintenance is designed and based on the analysis of client request types and severity (priority). In our approach, The Session attendees (Scrum Master, Product Owner and Team) choose that bug, issue or enhancement first which has an urgent type or higher priority request and resolves it then select low priority request or non-urgent requests and facilitates the clients in timely manner. In this way this proposed model works effectively and defiantly to meet the customer’s demand. A comprehensive study on product maintenance and support has been carried out which adds to the current practices in the scrum. We found that maintenance phase of the scrum has been given less attention in the existing literature. In view of this, we have made an attempt to propose a novel model that focuses on the maintenance phase of scrum.
Zubair Butt,Riffat Asim Pasha,Faisal Qayyum,Zeeshan Anjum,Nasir Ahmad,Hassan Elahi 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.8
Energy harvesting is the process of attaining energy from the external sources and transforming it into usable electrical energy. An analytical model of piezoelectric energy harvester has been developed to determine the output voltage across an electrical circuit when it is forced to undergo a base excitation. This model gives an easy approach to design and investigate the behavior of piezoelectric material. Numerical simulations have been carried out to determine the effect of frequency and loading on a Lead zirconate titanate (PZT-5A) piezoelectric material. It has been observed that the output voltage from the harvester increases when loading increases whereas its resonance frequency decreases. The analytical results were found to be in good agreement with the experimental and numerical simulation results.
Corrosion and wear behavior of TiN PVD coated 304 stainless-steel
Awais Awan,Riffat Asim Pasha,Muhammad Shoaib Butt,Rizwan Ahmed Malik,Ibrahim M Alarifi,Meshal Alzaid,무하마드 라티프,Ammar Naseer,Mohsin Saleem,Hussein Alrobei 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.8
Ti/TiN multilayered physical vapor deposition (PVD) coatings were deposited on stainless-steel by cathodic arc deposition method. Bare sample of stainless steel 304 was compared with monolithic TiN coating and TiN coating having 2, 4, 6 and 8 Ti interlayers. The properties like corrosion and wear resistance were studied and analyzed comparatively. Potentiodynamic polarization curves showed that highest corrosion resistance was indicated by TiN coating with 8 Ti interlayers. Sample having 8 Ti interlayers have high corrosion potential (E corr ) and low corrosion current density (I corr ) as compared to other samples. This may be attributed to the arrangement of interlayers that prevents the corrosive agents to penetrate surface. All multilayered coatings show better results than the substrate material. Pin on disk wear test revealed that coating having monolithic TiN layer have the lowest coefficient of friction and consequently have less wear volume and wear rate as compared to other coatings with Ti interlayers. These results made the investigated coated stainless steel 304 valuable for wide range of industrial applications that required wear and corrosion resistance.
Experimental Study On Solar Clothes Dryer using Evacuated Tube Collector and PV Panel
Jie Zhu,Saffa Riffat,Armando C. Oliveira 한국에너지기후변화학회 2008 에너지기후변화학회지 Vol.3 No.2
A solar dryer for clothes and its testing results are presented in this paper. The dryer combines a solar thermal collector with a photo voltaic panel to supply hot dry air for clothes, but can also be used for food drying applications. Twin-glass evacuated tubes with heat pipes are used in the solar collector as the main heat source, while DC fans powered by a PV panel are used as the power source for hot air circulation in this unit. The performance of the dryer was tested under the UK real weather conditions. The air in the dryer is heated by more than 17℃ and the humidity is decreased more than 20% for a solar collector mea of 0.78㎡ and a PV panel mea of 0.68 ㎡. The average water removing rate is 0.464 ㎏/h for a solar irradiation of 646.5 W/㎡.
Numerical Analysis on the use of Gases as a Working Fluid in the Vortex Tube
W. Rattanongphisat,S.B. Riffat 한국에너지기후변화학회 2008 에너지기후변화학회지 Vol.3 No.2
The use of compressed gases as a working fluid in the vortex lube is studied. Numerical method is used to investigate the effect of gas types on the temperature separation. A mathematical model is presented and used to predict the generated cold and hot temperature. The degree of temperature difference between inlet and outlets, cold and hot streams, is compared and presented the separation performance of each working fluid. The modeling is setup regarding energy and mass balance and the thermo-physical parameters: pressure ratio, specific heat ratio and inlet temperature. Simulation results are compared with the experimental literature data that the use of monatomic gas is apparent better performance.
Characterizing Barium Titanate Piezoelectric Material Using the Finite Element Method
Zubair Butt,Shafiq Ur Rahman,Riffat Asim Pasha,Shahid Mehmood,Saqlain Abbas,Hassan Elahi 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.3
The aim of the current research was to develop and present an effective methodology for simulating and analyzingthe electrical and structural properties of piezoelectric material. The finite element method has been used to makeprecise numerical models when dielectric, piezoelectric and mechanical properties are known. The static anddynamic responses of circular ring-shaped barium titanate piezoelectric material have been investigated using thecommercially available finite element software ABAQUS/CAE. To gain insight into the crystal morphology and toevaluate the purity of the material, a microscopic study was conducted using a scanning electron microscope andenergy dispersive x-ray analysis. It is found that the maximum electrical potential of 6.43 V is obtained at a resonancefrequency of 35 Hz by increasing the vibrating load. The results were then compared with the experimentally predicteddata and the results agreed with each other.
Characterizing Barium Titanate Piezoelectric Material Using the Finite Element Method
Butt, Zubair,Rahman, Shafiq Ur,Pasha, Riffat Asim,Mehmood, Shahid,Abbas, Saqlain,Elahi, Hassan The Korean Institute of Electrical and Electronic 2017 Transactions on Electrical and Electronic Material Vol.18 No.3
The aim of the current research was to develop and present an effective methodology for simulating and analyzing the electrical and structural properties of piezoelectric material. The finite element method has been used to make precise numerical models when dielectric, piezoelectric and mechanical properties are known. The static and dynamic responses of circular ring-shaped barium titanate piezoelectric material have been investigated using the commercially available finite element software ABAQUS/CAE. To gain insight into the crystal morphology and to evaluate the purity of the material, a microscopic study was conducted using a scanning electron microscope and energy dispersive x-ray analysis. It is found that the maximum electrical potential of 6.43 V is obtained at a resonance frequency of 35 Hz by increasing the vibrating load. The results were then compared with the experimentally predicted data and the results agreed with each other.
Arshad Mehmood,Sheher Bano,Aisha Fahim,Riffat Parveen,Shazia Khurshid 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.5
The adsorption capabilities of Syzygium cumini leaves were investigated for crystal violet and eosin B using batch adsorption method. Removal conditions were optimized by varying operational parameters like pH, dose of adsorbent, contact time and temperature. Presence of salts had a profound effect on the adsorption and the experimental data for both adsorbates, providing good correlation with the Temkin, Langmuir and Freundlich patterns, but differing from Dubinin-Radushkevich model. Maximum adsorption capacity was found to be 38.75 mg/g for crystal violet and 16.28mg/g for eosin B respectively. Boyd-Adamson-Myers, Morris-Weber and Bangham’s surface mass transport models revealed that film diffusion was the rate controlling process and followed pseudo-second order kinetics. Activation energy was estimated to be 57.265 and 6.721 kJ/mol for crystal violet and eosin B respectively. Adsorption of crystal violet is endothermic and that of Eosin B is exothermic but both were spontaneous at all temperatures. To study the bulk removal of the dyes, column operations were made. The exhausted columns were regenerated by eluting HCl solution and almost 91.94% of CV and 58.08% of EB were recovered from columns, respectively.