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Influence Of Flow Rate, Nozzle Speed, Pitch And The Number Of Passes On The Thickness Of S1805 Photoresist In Suss Microtec As8 Spray Coater, Rohan Sanghvi, Gyuseok Kim 2019 Singh Center for Nanotechnology

Influence Of Flow Rate, Nozzle Speed, Pitch And The Number Of Passes On The Thickness Of S1805 Photoresist In Suss Microtec As8 Spray Coater, Rohan Sanghvi, Gyuseok Kim

Tool Data

S1805 positive photoresist has been deposited on single crystalline Si wafers using a Suss MicroTec Alta Spray. The influence of flow rate, nozzle speed, pitch and number of passes on the thickness of the photoresist was studied. Results show that the thickness of S1805 is linearly proportional to the flow rate and number of passes, and inversely proportional to the nozzle speed and pitch.


Correction Of Pattern Size Deviations In The Fabrication Of Photomasks Made With A Laser Direct-Writer, Ningzhi Xie, George Patrick Watson 2019 Singh Center for Nanotechnology

Correction Of Pattern Size Deviations In The Fabrication Of Photomasks Made With A Laser Direct-Writer, Ningzhi Xie, George Patrick Watson

Protocols and Reports

When using Heidelberg DWL66+ laser writer to fabricate the photomask, the pattern feature dimensions may have deviations. These deviations can be caused by the lithography process and the undercut in the metal etch process. The same deviation value of 0.8µm was found to appear in all the patterns independent of the pattern original size and local pattern density. To overcome this universal deviation, a universal bias is suggested to be applied to the original patterns during the data preparation for the lithography process. In order to ensure this pre-exposure bias method can work, both the laser direct-write exposure conditions ...


Modelling The Addition Of Limestone In Cement Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer 2019 Technological University Dublin

Modelling The Addition Of Limestone In Cement Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Hydration models can aid in the prediction, understanding and description of hydration behaviour over time as the move towards more sustainable cements continues.

HYDCEM is a new model to predict the phase assemblage, degree of hydration and heat release over time for cements undergoing hydration for any w/c ratio and curing temperatures up to 450C. HYDCEM, written in MATLAB, complements more sophisticated thermodynamic models by predicting these properties over time using user-friendly inputs within one code. A number of functions and methods based on up to date cement hydration behaviour from the literature are hard-wired into the code along ...


Effects Of Carbon-Based Ablation Products On Hypersonic Boundary Layer Stability, Olivia S. Elliot 2019 Air Force Institute of Technology

Effects Of Carbon-Based Ablation Products On Hypersonic Boundary Layer Stability, Olivia S. Elliot

Theses and Dissertations

Hypersonic vehicles require an accurate prediction of the transition of the boundary layer for the design of the thermal protection system due to the high heating rates under turbulent flow. Many thermal protection systems are carbon-based and introduce new species, specifically CO2, into the boundary layer flow which are known to dampen the instabilities that lead to transition for hypersonic vehicles. A Computation Fluid Dynamics study was accomplished examining the concentration of CO2 required to impact boundary layer transition over both sharp and blunt cones. These results were used in conjunction with air-carbon ablation models models to determine if ...


On The Pulsed Laser Ablation Of Metals And Semiconductors, Todd A. Van Woerkom 2019 Air Force Institute of Technology

On The Pulsed Laser Ablation Of Metals And Semiconductors, Todd A. Van Woerkom

Theses and Dissertations

This dissertation covers pulsed laser ablation of Al, Si, Ti, Ge, and InSb, with pulse durations from tens of picosecond to hundreds of microseconds, fluences from ones of J/cm2 to over 10,000 J/cm2, and in ambient air and vacuum. A set of non-dimensional scaling factors was created to interpret the data relative to the laser and material parameters, and it was found that pulse durations shorter than a critical timescale formed craters much larger than the thermal diffusion length, and longer pulse durations created holes much shallower than the thermal diffusion length. Low transverse order ...


Life Cycle Cost Evaluation Strategy For High Performance Control Systems Under Uncertainties, Laura Micheli, Ling Cao, Simon Laflamme, Alice Alipour 2019 Iowa State University

Life Cycle Cost Evaluation Strategy For High Performance Control Systems Under Uncertainties, Laura Micheli, Ling Cao, Simon Laflamme, Alice Alipour

Simon Laflamme

High-performance control systems (HPCSs), including active, hybrid, and semi-active control strategies, can perform over a wide excitation bandwidth and are therefore good candidates for multi-hazard mitigation. However, the number of HPCS applications in the field is very limited. This is likely due the perceived high costs of installation, maintenance, possible malfunction, and lack of tools to financially justify their implementation. Such financial justifications could be conducted through life cycle cost (LCC) analysis, but would result in a computationally demanding task due to the very large number of simulations required given the large number of uncertainties. In this paper, two sets ...


Principal Component Neural Networks For Modeling, Prediction, And Optimization Of Hot Mix Asphalt Dynamics Modulus, Parnian Ghasemi, Mohamad Aslani, Derrick K. Rollins, R. Christopher Williams 2019 Iowa State University

Principal Component Neural Networks For Modeling, Prediction, And Optimization Of Hot Mix Asphalt Dynamics Modulus, Parnian Ghasemi, Mohamad Aslani, Derrick K. Rollins, R. Christopher Williams

Derrick K Rollins, Sr.

The dynamic modulus of hot mix asphalt (HMA) is a fundamental material property that defines the stress-strain relationship based on viscoelastic principles and is a function of HMA properties, loading rate, and temperature. Because of the large number of efficacious predictors (factors) and their nonlinear interrelationships, developing predictive models for dynamic modulus can be a challenging task. In this research, results obtained from a series of laboratory tests including mixture dynamic modulus, aggregate gradation, dynamic shear rheometer (on asphalt binder), and mixture volumetric are used to create a database. The created database is used to develop a model for estimating ...


Interface Effects On He Ion Irradiation In Nanostructured Materials, Wenfan Yang, Jingyu Pang, Shijian Zheng, Jian Wang, Xinghang Zhang, Xiuliang Ma 2019 Chinese Academy of Sciences & University of Science and Technology of China

Interface Effects On He Ion Irradiation In Nanostructured Materials, Wenfan Yang, Jingyu Pang, Shijian Zheng, Jian Wang, Xinghang Zhang, Xiuliang Ma

Mechanical & Materials Engineering Faculty Publications

In advanced fission and fusion reactors, structural materials suffer from high dose irradiation by energetic particles and are subject to severe microstructure damage. He atoms, as a byproduct of the (n) transmutation reaction, could accumulate to form deleterious cavities, which accelerate radiation-induced embrittlement, swelling and surface deterioration, ultimately degrade the service lifetime of reactor materials. Extensive studies have been performed to explore the strategies that can mitigate He ion irradiation damage. Recently, nanostructured materials have received broad attention because they contain abundant interfaces that are efficient sinks for radiation-induced defects. In this review, we summarize and analyze the current understandings ...


Principal Component Neural Networks For Modeling, Prediction, And Optimization Of Hot Mix Asphalt Dynamics Modulus, Parnian Ghasemi, Mohamad Aslani, Derrick K. Rollins, R. Christopher Williams 2019 Iowa State University

Principal Component Neural Networks For Modeling, Prediction, And Optimization Of Hot Mix Asphalt Dynamics Modulus, Parnian Ghasemi, Mohamad Aslani, Derrick K. Rollins, R. Christopher Williams

Chemical and Biological Engineering Publications

The dynamic modulus of hot mix asphalt (HMA) is a fundamental material property that defines the stress-strain relationship based on viscoelastic principles and is a function of HMA properties, loading rate, and temperature. Because of the large number of efficacious predictors (factors) and their nonlinear interrelationships, developing predictive models for dynamic modulus can be a challenging task. In this research, results obtained from a series of laboratory tests including mixture dynamic modulus, aggregate gradation, dynamic shear rheometer (on asphalt binder), and mixture volumetric are used to create a database. The created database is used to develop a model for estimating ...


On The Formation Of The Variational Equation Of Motion And Boundary Value Problems Of Thin-Walled Axisymmetric Shell Structures, A. Abdusattarov, F.E. Abduqodirov, N.H. Sabirov 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

On The Formation Of The Variational Equation Of Motion And Boundary Value Problems Of Thin-Walled Axisymmetric Shell Structures, A. Abdusattarov, F.E. Abduqodirov, N.H. Sabirov

Journal of Tashkent Institute of Railway Engineers

The article deals, on the basis of the Hamilton-Ostrogradsky variational principle, a system of differential equations of motion of axisymmetric shell structures with the corresponding boundary and initial conditions is derived. The boundary problem for cylindrical and spherical shell structures is formulated


About Movements Of The Carriage On The Profile Hump In A Gravity Yard, Sh.B. Djabbarov 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

About Movements Of The Carriage On The Profile Hump In A Gravity Yard, Sh.B. Djabbarov

Journal of Tashkent Institute of Railway Engineers

The article noted that in the existing methods of calculation of hump in a gravity yards the speed of the car at the braking position is determined by the formula speed of free fall of bodies given the inertia in the rotating parts of the car. Thus assume that in areas of deceleration occur rotation of the wheels of the car, that is incorrect. In it mathematical expressions and examples of calculations proved that the high-speed sections slides occur the rolling of the wheels of wheel pairs without slipping.


On The Application Of Information Technology For The Development Of Software For Automation The Modeling Process Of Wagons At Wagon Enterprises Jsc "O'Zbekiston Temir Yo'llari", V.P. Bubnov, Sh. Kh. Sultonov 2019 Emperor Alexander I St. Petersburg State Transport University, Saint Petersburg, Russia

On The Application Of Information Technology For The Development Of Software For Automation The Modeling Process Of Wagons At Wagon Enterprises Jsc "O'Zbekiston Temir Yo'llari", V.P. Bubnov, Sh. Kh. Sultonov

Journal of Tashkent Institute of Railway Engineers

The report presents a functional diagram of the developed software for calculating the values of loads acting on the wagon body. The stages of development and the main modules of a software product that implements mathematical calculations are defined. The issues of the software implementation of the presented algorithms using the object-oriented programming language C # are discussed. The performed engineering analysis using the values of loads obtained using the developed software is given. The developed program in C # language with the use of the integrated Visual Studio environment allows to increase the accuracy and reduce the time for calculating the ...


Modeling Of Theflow Regimes Of Water-Coal Fuel Slurries With Complex Reology In Cylindrical Pipes, Ja.D. Hodzhaev, Sh.A. Kasymov 2019 Physical-technical institute NGO "Physics-sun", ASUz, Tashkent, Uzbekistan

Modeling Of Theflow Regimes Of Water-Coal Fuel Slurries With Complex Reology In Cylindrical Pipes, Ja.D. Hodzhaev, Sh.A. Kasymov

Journal of Tashkent Institute of Railway Engineers

The article deals the flow regimes with regard to the complex flow rheology of highly concentrated water-coal fuel slurries (WCS). It has been established that during the WCS flow through cylindrical pipes the flow mode is disturbed, which is due to the mutual influence of the geometric dimensions and flow parameters of the suspension when it is burned in the combustion chambers of power plants


Boolean Complement Method For Combinational Circuits Testing Using Binary Separable Codes, A.H. Efanov 2019 Russian University of Transport, Moscow, Russia

Boolean Complement Method For Combinational Circuits Testing Using Binary Separable Codes, A.H. Efanov

Journal of Tashkent Institute of Railway Engineers

The concurrent error-detection systems basic structural diagrams based on the check bits calculation and on the logical addition basis are described. A hybrid block diagram is presented in which the part of the diagnostics object outputs is transformed. The conditions for the use of binary separable codes for their use in the concurrent error-detection systems organization according to the method of logical addition are established.


On The Construction Of Canonical Systems Of Equations For Cylindrical And Spherical Shell Structures, A. Abdusattarov, F.E. Abduqodirov 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

On The Construction Of Canonical Systems Of Equations For Cylindrical And Spherical Shell Structures, A. Abdusattarov, F.E. Abduqodirov

Journal of Tashkent Institute of Railway Engineers

In this article is given the construction of canonical systems, the equation of motion for axisymmetric shell structures, as well as for cylindrical and spherical shells


Calculation Of The Wagon Motion Velocation On The Whole Protection Of The Profile Of The Way With Different Clothes Of The Sorting Hill, Kh.Kh. Djalilov 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

Calculation Of The Wagon Motion Velocation On The Whole Protection Of The Profile Of The Way With Different Clothes Of The Sorting Hill, Kh.Kh. Djalilov

Journal of Tashkent Institute of Railway Engineers

In this article has been calculated the velocity of the wagon’s movement in various sites of a hump yard, based on the formula led on the basis of the theorem of changing of kinetic energy for not free material point in a final form. Results of the calculations are noticed that on the intermediate site of a hump yard to a dividing arrow the relative error of calculation is equal to 10.3%, on the site of an arrow zone of a hump yard of the second dividing arrow - δv6с2 ≈ 9.0%, on the site of the first sorting ...


Features Of Thermal Processing Of Instrumental Alloyed Steels, F.R. Norkhudjayev, A.A. Mukhamedov, D.M. Ergashev 2019 Tashkent State Technical University named after Islam Karimov, Tashkent, Uzbekistan

Features Of Thermal Processing Of Instrumental Alloyed Steels, F.R. Norkhudjayev, A.A. Mukhamedov, D.M. Ergashev

Journal of Tashkent Institute of Railway Engineers

In work, the most preferred heat treatment scheme has been determined on the basis of the analysis of various heat treatment schemes for alloyed tool steels, which the excludes the possibility of restoring the original grain structure and retains the possibility of studying the increased material defectiveness acquired during primary hardening.


To The Movement Of The Car On The Site Of The First Brake Hump Yard Of Positions, Sh.U. Saidivaliyev 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

To The Movement Of The Car On The Site Of The First Brake Hump Yard Of Positions, Sh.U. Saidivaliyev

Journal of Tashkent Institute of Railway Engineers

In the article using the analytical formulas derived from the application of the basic law of dynamics for non-ideal connections (Dalembert principle), the kinematic parameters of the car’s motion (acceleration, time, braking path) were calculated in the deceleration zone at the site of the first brake position of the hump yard


Research Of Surface Condition Of The Rails Rolling On Sections Of High-Speed And High-Speed Train Traffic, E.B. Abdualiyev 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

Research Of Surface Condition Of The Rails Rolling On Sections Of High-Speed And High-Speed Train Traffic, E.B. Abdualiyev

Journal of Tashkent Institute of Railway Engineers

In this article, the analysis of intensity of the pulse roughness’s arising on a surface of rolling of heads of rails on a site of high-speed movement of trains is carried out.


The Movement Of Trains As A Source Of Seismic Waves Impact On The Upper Structure Of The Track And The Roadbed Of Railways, A.H. Abdujabarov, P. A. Begmatov, M. Mehmonov 2019 Tashkent Institute of Railway Engineers, Tashkent, 100167, Uzbekistan

The Movement Of Trains As A Source Of Seismic Waves Impact On The Upper Structure Of The Track And The Roadbed Of Railways, A.H. Abdujabarov, P. A. Begmatov, M. Mehmonov

Journal of Tashkent Institute of Railway Engineers

On the basis of theoretical and experimental scientific research, the substantiation of the similarity of the impact of seismic forces and the movement of rolling stock on the engineering structures of Railways is obtained.


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