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26 - تحليل تأثيرگذاري ميزان مقاومت حرارتي جداره و جهت جداره هاي نورگذر بر اندازه بهينه پنجره در اقليم تهران, Mona Khatami, Maria Kord-Jamshidi, Behrouz Mohamad Kari, Alireza Zolfaghari Dec 2012

26 - تحليل تأثيرگذاري ميزان مقاومت حرارتي جداره و جهت جداره هاي نورگذر بر اندازه بهينه پنجره در اقليم تهران, Mona Khatami, Maria Kord-Jamshidi, Behrouz Mohamad Kari, Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.


25 - تحليل تأثيرات استفاده از عايقهاي تغيير فاز دهنده بر ميزان مصرف سالانه انرژي ساختمان در اقليم تهران, Alireza Zolfaghari, Mohamad Solhi, Mohamad Fathian, Hamed Moslehi, Mohamad Rahim-Pour, Mehran Sa'adati-Nasab Dec 2012

25 - تحليل تأثيرات استفاده از عايقهاي تغيير فاز دهنده بر ميزان مصرف سالانه انرژي ساختمان در اقليم تهران, Alireza Zolfaghari, Mohamad Solhi, Mohamad Fathian, Hamed Moslehi, Mohamad Rahim-Pour, Mehran Sa'adati-Nasab

Dr Alireza Zolfaghari

No abstract provided.


24 - تحليل عملکرد کانالهاي زير زميني جهت تامين هواي لازم براي تهويه فضاهاي صنعتی با در نظر گرفتن زمان لازم براي احياي سيستم, Alireza Zolfaghari, Mozhgan Nikoudel, Hosein Vatan-Pour Dec 2012

24 - تحليل عملکرد کانالهاي زير زميني جهت تامين هواي لازم براي تهويه فضاهاي صنعتی با در نظر گرفتن زمان لازم براي احياي سيستم, Alireza Zolfaghari, Mozhgan Nikoudel, Hosein Vatan-Pour

Dr Alireza Zolfaghari

No abstract provided.


Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss Dec 2012

Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss

Gijsbert Wierink

The interaction between gasses, liquids, and solids plays a critical role in many processes, such as coating, granulation and the blast furnace process. In this paper we present a comprehensive numerical model for three phase flow including droplets, particles and gas. By means of a coupled Computational Fluid Dynamics (CFD) - Discrete Element Method (DEM) approach the physical core phenomena are pictured at a detailed level. Sub-models for droplet deformation, breakup and coalescence as well as droplet-particle and wet particle-particle interaction are applied. The feasibility of this model approach is demonstrated by its application to a rotating drum coater. The …


Combustion Characteristics Of Late Injected Cng In A Spark Ignition Engine Under Lean Operating Condition, Ftwi Yohaness Hagos, A. Rahsid Abd Aziz, Shaharin A. Sulaiman Dec 2012

Combustion Characteristics Of Late Injected Cng In A Spark Ignition Engine Under Lean Operating Condition, Ftwi Yohaness Hagos, A. Rahsid Abd Aziz, Shaharin A. Sulaiman

Ftwi Yohaness Hagos

Lean combustion strategy is used as a tool in the reduction of greenhouse gas emission in a natural gas fuelled engines. It also increases the thermal efficiency of the combustion. In this study, late injection and stratification effect of lean charge CNG combustion in a four stroke direct injection spark ignited engine was experimentally investigated. The fuel injection is kept at 90° Crank Angle (CA) Before Top Dead Center (BTDC) and the ignition timing at 28° CA BTDC at wide open throttle. Results from this study demonstrate that Indicated Mean Effective Pressure (IMEP), it's Coefficient Of Variation (COV), in cylinder …


خلاصه روابط و معادلات Dec 2012

خلاصه روابط و معادلات

Dr Alireza Zolfaghari

No abstract provided.


Ios Model Viewer, Benjamin M. Sloan Dec 2012

Ios Model Viewer, Benjamin M. Sloan

Benjamin M. Sloan

The OBJ model viewer for iOS was developed to enable an iPad to display and allow users to interact with a design as it was being three-dimensionally printed. Current iOS application restrict user interaction to a single still view or a slide show of still views. The iOS OBJ Loader was first attempted to be written in openGL es but a custom library ended being used called Nevenah to develop the application. In addition to interacting with the loaded model the users could also adjust the lighting to understand how the material reflected light and also load different models that …


Storage Stability Of Biofuel, Mahendra Varman Munusamy M. Varman Nov 2012

Storage Stability Of Biofuel, Mahendra Varman Munusamy M. Varman

Mahendra Varman Munusamy (M. Varman)

Biofuel is one of the prime candidates to take over the role played by fossil fuel as the main source of energy in the future. Numerous studies have been done on the potential of biofuel to produce similar power output generated by the current petrol and diesel which are depleting without any drawbacks. The objective of this particular study is to investigate 4 of the more established vegetable oil in the energy industry namely jatropha, palm, coconut and canola oil in terms of storage stability of biofuel at room temperature and 80ºC. The biofuels were tested in terms of density, …


Super Critical Steam Turbine, Vijaya Krushna Varma Mr Nov 2012

Super Critical Steam Turbine, Vijaya Krushna Varma Mr

VIJAYA KRUSHNA VARMA Mr

Varma designed ultra modern and high efficiency turbines which can use gas, steam or fuels as feed to produce electricity or mechanical work for wide range of usages and applications in industries or at work sites. Varma turbine engines can be used in all types of vehicles. These turbines can also be used in aircraft, ships, battle tanks, dredgers, mining equipment, earth moving machines etc http://turbine.net.in


How To Save Money On Your Next Set Of Patent Drawings., Bernadette Marshall Oct 2012

How To Save Money On Your Next Set Of Patent Drawings., Bernadette Marshall

Bernadette Marshall

In this edition we will cover the most cost effective choices of reference materials when ordering patent drawings. The type of reference material you supply your draftsperson directly influences the price you pay for patent drawings. Reference material comes in many forms and the better you are at identifying the most useful reference materials, the less you will pay for drawings. It's not complicated and with the following tips I hope you will save money on your next set of patent drawings.


Designing New Energy System Components, Benjamin M. Sloan Oct 2012

Designing New Energy System Components, Benjamin M. Sloan

Benjamin M. Sloan

The topic discussed how the metaphors that are used when designing a product are restrictive not allowing for alternative designs to be considered. Digital manufacturing specifically three-dimensional printing are disruptive manufacturing technologies, now being able to control manufacturing from atom to item. The result of this disruption is a shift in how we apply metaphors of old manufacturing onto these new topics without these restrictions either by forming new metaphors or adapting metaphors of old.


An Exercise With The He’S Variation Iteration Method To A Fractional Bernoulli Equation Arising In A Transient Conduction With A Non-Linear Boundary Heat Flux, Jordan Hristov Oct 2012

An Exercise With The He’S Variation Iteration Method To A Fractional Bernoulli Equation Arising In A Transient Conduction With A Non-Linear Boundary Heat Flux, Jordan Hristov

Jordan Hristov

Surface temperature evolution of a body subjected to a nonlinear heat flux involving counteracting convection heating and radiation cooling has been solved by the variations iteration method (VIM) of He. The surface temperature equations comes as a combination of the time-fractional (half-time) subdiffusion model of the heat conduction and the boundary condition relating the temperature field gradient at the surface through the Riemann-Liouville fractional integral. The result of this equation is a Bernoulli-type ordinary fractional equation with a nonlinear term of 4th order. Two approaches in the identification of the general Lagrange multiplier and a consequent application of VIM have …


Best Source For Patent Drawing Rules & Regulations, Bernadette Marshall Sep 2012

Best Source For Patent Drawing Rules & Regulations, Bernadette Marshall

Bernadette Marshall

It is with great pleasure that I announce something new from NBG-Drafting and Design. This is our first Newsletter - Special Edition; In this edition we will cover our preferred sources for patent drawing rules & regulations. Finding resources for information regarding patent drawing rules can be frustrating. Much of the information refers to out-of-date methods, like hand drawings using ink pens on board. It is hard to imaging creating any type of mechanical/technical drawings today without the use of CADD (software application for computer aided design and drafting). Most skilled patent draftspersons today are practicing in CADD.


Sound Absorption Properties Of Functionally Graded Polyurethane Foams, Olivier Doutres Ph.D., Noureddine Atalla Pr. Aug 2012

Sound Absorption Properties Of Functionally Graded Polyurethane Foams, Olivier Doutres Ph.D., Noureddine Atalla Pr.

Olivier Doutres Ph.D.

Noise control over a wide frequency band is an increasingly important design criterion in the building and transport industries. Examples of well known broadband passive concepts for optimal sound absorption are multi-layering with graded properties across the thickness and optimization of the material shape (e.g., wedges). However, for typical applications, the material thickness is limited and shaping or use of different material costly. Thus, there is growing interest for developing acoustical materials having microstructure properties gradient at the micro- or meso-scale; also known as Functionally Graded Materials (FGM). Even if sophisticated models are available to predict the acoustic behavior of …


Hydrogen Production From Steam Reforming Of Coke Oven Gas And Its Utility For Indirect Reduction Of Iron Oxides In Blast Furnace, Wei-Hsin Chen Aug 2012

Hydrogen Production From Steam Reforming Of Coke Oven Gas And Its Utility For Indirect Reduction Of Iron Oxides In Blast Furnace, Wei-Hsin Chen

Wei-Hsin Chen

No abstract provided.


Environmental Impacts Of Stover Removal In The Corn Belt, Alicia English, Wallace E. Tyner, Juan Sesmero, Phillip Owens, David J. Muth Jr. Aug 2012

Environmental Impacts Of Stover Removal In The Corn Belt, Alicia English, Wallace E. Tyner, Juan Sesmero, Phillip Owens, David J. Muth Jr.

David J. Muth

When considering the market for biomass from corn stover resources erosion and soil quality issues are important to consider. Removal of stover can be beneficial in some areas, especially when coordinated with other conservation practices, such as vegetative barrier strips and cover crops. However, benefits are highly dependent on several factors, namely if farmers see costs and benefits associated with erosion and the tradeoffs with the removal of biomass. This paper uses results from an integrated RUSLE2/WEPS model to incorporate six different regime choices, covering management, harvest and conservation, into a simple profit maximization model to show these tradeoffs.


Integral-Balance Solution To The Stokes’ First Problem Of A Viscoelastic Generalized Second Grade Fluid, Jordan Hristov Jun 2012

Integral-Balance Solution To The Stokes’ First Problem Of A Viscoelastic Generalized Second Grade Fluid, Jordan Hristov

Jordan Hristov

Integral balance solution employing entire domain approximation and the penetration dept concept to the Stokes’ first problem of a viscoelastic generalized second grade fluid has been developed. The solution has been performed by a parabolic profile with an unspecified exponent allowing optimization through minimization of the norm over the domain of the penetration depth. The closed form solution explicitly defines two dimensionless similarity variables and , responsible for the viscous and the elastic responses of the fluid to the step jump at the boundary. The solution was developed with three forms of the governing equation through its two dimensional forms …


Thermal Impedance At The Interface Of Contacting Bodies: 1-D Example Solved By Semi-Derivatives, Jordan Hristov Jun 2012

Thermal Impedance At The Interface Of Contacting Bodies: 1-D Example Solved By Semi-Derivatives, Jordan Hristov

Jordan Hristov

Simple 1-D semi-infinite heat conduction problems enable to demonstrate the potential of the fractional calculus in determination of transient thermal impedances of two bodies with different initial temperatures contacting at the interface ( ) at . The approach is purely analytic and uses only semi-derivatives (half-time) and semi-integrals in the Riemann-Liouville sense. The example solved clearly reveals that the fractional calculus is more effective in calculation the thermal resistances than the entire domain solutions


Application Of Higher Order Hamiltonian Approach To Nonlinear Vibrating Systems, Hassan Askari Jun 2012

Application Of Higher Order Hamiltonian Approach To Nonlinear Vibrating Systems, Hassan Askari


No abstract provided.


Design And Modelling Of A 330 Mwe Flexi-Burn® Cfb For Oxygen-Fired And Air-Fired Combustion, Kari Myöhänen, Timo Eriksson, Reijo Kuivalainen, Timo Hyppänen Jun 2012

Design And Modelling Of A 330 Mwe Flexi-Burn® Cfb For Oxygen-Fired And Air-Fired Combustion, Kari Myöhänen, Timo Eriksson, Reijo Kuivalainen, Timo Hyppänen

Kari Myöhänen

No abstract provided.


Three-Dimensional Modelling Of Steam-Oxygen Gasification In A Circulating Fluidized Bed, Kari Myöhänen, Matti Koski, Jouni Ritvanen, Timo Hyppänen, Juha Palonen, Katja Häkkinen, Sami Kokki Jun 2012

Three-Dimensional Modelling Of Steam-Oxygen Gasification In A Circulating Fluidized Bed, Kari Myöhänen, Matti Koski, Jouni Ritvanen, Timo Hyppänen, Juha Palonen, Katja Häkkinen, Sami Kokki

Kari Myöhänen

No abstract provided.


Three-Dimensional Modelling Of Circulating Fluidized Bed Processes By A Semi-Empirical Approach, Kari Myöhänen May 2012

Three-Dimensional Modelling Of Circulating Fluidized Bed Processes By A Semi-Empirical Approach, Kari Myöhänen

Kari Myöhänen

No abstract provided.


Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films Apr 2012

Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films

A.S. Md Abdul Haseeb

Nanocrystalline nickel-tungsten alloys have great potential in the fabrication of components for microelectromechanical systems. Here the fracture toughness of Ni-12.7 at.%W alloy micro-cantilever beams was investigated. Micro-cantilevers were fabricated by UV lithography and electrodeposition and notched by focused ion beam machining. Load was applied using a nanoindenter and fracture toughness was calculated from the fracture load. Fracture toughness of the Ni-12.7 at.%W was in the range of 1.49-5.14 MPa √m. This is higher than the fracture toughness of Si (another important microelectromechanical systems material), but considerably lower than that of electrodeposited nickel and other nickel based alloys. © 2012 Elsevier …


Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films Apr 2012

Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films

A.S. Md Abdul Haseeb

Nanocrystalline nickel-tungsten alloys have great potential in the fabrication of components for microelectromechanical systems. Here the fracture toughness of Ni-12.7 at.%W alloy micro-cantilever beams was investigated. Micro-cantilevers were fabricated by UV lithography and electrodeposition and notched by focused ion beam machining. Load was applied using a nanoindenter and fracture toughness was calculated from the fracture load. Fracture toughness of the Ni-12.7 at.%W was in the range of 1.49-5.14 MPa √m. This is higher than the fracture toughness of Si (another important microelectromechanical systems material), but considerably lower than that of electrodeposited nickel and other nickel based alloys. © 2012 Elsevier …


A Semi-Empirical Model To Predict The Acoustic Behaviour Of Fully And Partially Reticulated Polyurethane Foams Based On Microstructure Properties, Olivier Doutres Ph.D., Noureddine Atalla Apr 2012

A Semi-Empirical Model To Predict The Acoustic Behaviour Of Fully And Partially Reticulated Polyurethane Foams Based On Microstructure Properties, Olivier Doutres Ph.D., Noureddine Atalla

Olivier Doutres Ph.D.

This work investigates the links between the microstructure of polyurethane foams and their sound absorbing efficiency, and more specifically the effect of membranes closing the cells. In a previous work, the authors proposed a semi-empirical approach to link the foam microstructure properties, i.e. reticulation rate, strut length and thickness, with its non-acoustic parameters. The study was based on the complete characterization of 15 isotropic polyurethane foams with various cell sizes and reticulation rates (i.e. open pore content). This paper proposes a validation of this semi-empirical model using 3 new polyurethane foams, not used in the first characterization set. More importantly, …


Degradation Of Automotive Materials In Palm Biodiesel Apr 2012

Degradation Of Automotive Materials In Palm Biodiesel

A.S. Md Abdul Haseeb

As compared to petroleum diesel, biodiesel is more corrosive for automotive materials. Studies on the characterization of corrosion products of fuel exposed automotive materials are scarce. Automotive fuel system and engine components are made from different ferrous and non-ferrous materials. The present study aims to investigate the corrosion products of different types of automotive materials such as copper, brass, aluminum and cast iron upon exposure to diesel and palm biodiesel. Changes in fuel properties due to exposure of different materials were also examined. Degradation of metal surface was characterized by digital camera, SEM/EDS and X-ray diffraction (XRD). Fuel properties were …


Preparation And Low-Temperature Sintering Of Cu Nanoparticles For High-Power Devices Apr 2012

Preparation And Low-Temperature Sintering Of Cu Nanoparticles For High-Power Devices

A.S. Md Abdul Haseeb

One of the fundamental requirements for high-temperature electronic packaging is reliable silicon attach with low and stable electrical resistance. This paper presents a study conducted on Cu nanoparticles as an alternative lead-free interconnect material for high-temperature applications. Cu nanoparticles were prepared using pulsed wire evaporation technique in water medium. Pure Cu nanoparticles without any organic mixture were used in this paper. An economical approach to extract the nanoparticles from water was established. In situ Cu nanoparticles oxide reduction was successfully done using forming gas $({\rm N}-{2}{\hbox{-}}5\%{\rm H}-{2})$. Cross-section analysis on bonded interface shows onset of Cu nanoparticles sintering at 400$^{\circ}{\rm …


Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films, Haseeb Asma Apr 2012

Nanoindentation And Micro-Mechanical Fracture Toughness Of Electrodeposited Nanocrystalline Ni-W Alloy Films, Haseeb Asma

Haseeb ASMA

Nanocrystalline nickel-tungsten alloys have great potential in the fabrication of components for microelectromechanical systems. Here the fracture toughness of Ni-12.7 at.%W alloy micro-cantilever beams was investigated. Micro-cantilevers were fabricated by UV lithography and electrodeposition and notched by focused ion beam machining. Load was applied using a nanoindenter and fracture toughness was calculated from the fracture load. Fracture toughness of the Ni-12.7 at.%W was in the range of 1.49-5.14 MPa root m. This is higher than the fracture toughness of Si (another important microelectromechanical systems material), but considerably lower than that of electrodeposited nickel and other nickel based alloys. (C) 2012 …


Preparation And Low-Temperature Sintering Of Cu Nanoparticles For High-Power Devices, Haseeb Asma Apr 2012

Preparation And Low-Temperature Sintering Of Cu Nanoparticles For High-Power Devices, Haseeb Asma

Haseeb ASMA

One of the fundamental requirements for high-temperature electronic packaging is reliable silicon attach with low and stable electrical resistance. This paper presents a study conducted on Cu nanoparticles as an alternative lead-free interconnect material for high-temperature applications. Cu nanoparticles were prepared using pulsed wire evaporation technique in water medium. Pure Cu nanoparticles without any organic mixture were used in this paper. An economical approach to extract the nanoparticles from water was established. In situ Cu nanoparticles oxide reduction was successfully done using forming gas (N-2-5% H-2). Cross-section analysis on bonded interface shows onset of Cu nanoparticles sintering at 400 degrees …


Analytical Approximate Solutions For The Generalized Nonlinear Oscillator, Hassan Askari Mar 2012

Analytical Approximate Solutions For The Generalized Nonlinear Oscillator, Hassan Askari


No abstract provided.