Advanced Micro Research Articles

DESIGN AND SIMULATION OF LOGIC CIRCUITS AT NANO SCALE BEYOND 32 NANO METERS (FINFET)

With advancement in electronic circuitry, efforts are made to minimize chip size and to attain the desired performance so on changing one parameter the other parameters are effected like variables of field effect transistor like length and width are key variables available to the circuit designer to optimize circuit performance .When in FET’s like CMOS (complementary metal oxide semiconductor) the dimensions are decreased, the short channel effect arises and creates a problem of concern. With this effect an exponential increase in the leakage current happens. In order to reduce the SCE and hence leakage current, a new technology came into being in recent years in which a 3D multiple gate CMOS like FinFet (Fin Field Effect Transistor) has been developed which possess advantages over conventional FET’s and has attracted many engineers and designers to make it more sophisticated. This technology works in the nano meter range to minimize short channel effects. Many companies like Intel, advanced micro device, global foundries have started using FinFet technology. I have carried out my work on the basis of current researches on FinFet technology and how FinFet technology can be used in future to design new logic and memory devices like Inverter, MUX etc. Various parameters of FinFet like reduced short channel effects, less leakage current, low power consumption, less propagation delay and less time delay are discussed. Various mathematical models and software were used to simulate power, delay, power delay product, average power dissipation and energy delay products, this technology was designed to eliminate the problem of SCE by permitting transistors to be scaled down into sub 20nm range. Use of PMT model to design different logic devices at 16nm technology and analyzed output of each circuit. Parameters like Power dissipation, time delay and PDP were compared between MOSFET (CMOS) technology and FinFet technology for each circuit.

Evaluation of the Basic Neutronics and Thermal-Hydraulics for the Safety Evaluation of the Advanced Micro Reactor (Amr)

Evaluation of the Basic Neutronics and Thermal-Hydraulics for the Safety Evaluation of the Advanced Micro Reactor (Amr)

Design And Verification Of Advanced Peripheral Bus Protocol Using Uvm

The System on chip uses advanced micro controller bus architecture is on chip bus introduced by ARM. Advanced peripheral bus is the component of the AMBA bus architecture. APB is low bandwidth, low power and low performance it used to connect the peripherals like UART, Keypad, Timer and other peripheral devices to the bus architecture. This introduces the AMBA APB bus using UVM architecture design. The design created using the Verilog and HDL and tested by Verilog test bench and design is verified using universal verification methodology. In this, we have a master and a slave. The master sends the control signals as a packet to the slave and the slave addresses the packet if both are equal we are getting transaction of write and read data, Where the master send the address slave recognize and it sends the signal to the master as a read data.

Design And Verification Of Advanced Peripheral Bus Protocol Using Uvm

The System on chip uses advanced micro controller bus architecture is on chip bus introduced by ARM. Advanced peripheral bus is the component of the AMBA bus architecture. APB is low bandwidth, low power and low performance it used to connect the peripherals like UART, Keypad, Timer and other peripheral devices to the bus architecture. This introduces the AMBA APB bus using UVM architecture design. The design created using the Verilog and HDL and tested by Verilog test bench and design is verified using universal verification methodology. In this, we have a master and a slave. The master sends the control signals as a packet to the slave and the slave addresses the packet if both are equal we are getting transaction of write and read data, Where the master send the address slave recognize and it sends the signal to the master as a read data.

Gas-lift enhanced natural circulation of alkali and heavy liquid metals for passive cooling of nuclear reactors

Gas-lift enhanced natural circulation of alkali and heavy liquid metals is a desirable option for passive cooling of advanced large, small, and micro nuclear reactors, accelerator driven systems, thermal solar plants, and experimental facilities and test loops. The injected inert gas into the riser or the chimney above the reactor core needs to be in the bubbly flow regime for best performance. Gas-heavy liquid metals flow maps are developed based on a well-established theoretical knowledge and the reported experimental data for various test loops. In addition, a thermal-hydraulics model for enhanced natural circulation of heavy liquid metals is developed and validated using the reported experimental data for LBE-N2 and LBE-Ar flow loops. The developed and validated thermal-hydraulics model and two-phase flow maps are used to parametrically investigate natural circulation enhancement of liquid sodium, molten lead, and liquid LBE in a representative loop with Ar gas injection. For enhanced natural circulation of alkali and heavy liquids metals of Na, Pb and LBE, the determined average gas void fraction in the bubbly flow regime is < 0.2. The rates of natural circulation of liquid sodium, molten lead, and liquid LBE increase with increased riser height and/or the gas injection rate for operating in the bubbly flow regime. For the same riser height and gas average void fraction, the natural circulation rates of molten Pb and LBE are similar but much higher than that of liquid sodium. However, liquid sodium has a much higher heat capacity for operating at higher fission power density in or lower temperature rise across the reactor core.

Outbreaks of COVID-19 variants in US prisons: a mathematical modelling analysis of vaccination and reopening policies

BackgroundResidents of prisons have experienced disproportionate COVID-19-related health harms. To control outbreaks, many prisons in the USA restricted in-person activities, which are now resuming even as viral variants proliferate. This study aims to use mathematical modelling to assess the risks and harms of COVID-19 outbreaks in prisons under a range of policies, including resumption of activities.MethodsWe obtained daily resident-level data for all California state prisons from Jan 1, 2020, to May 15, 2021, describing prison layouts, housing status, sociodemographic and health characteristics, participation in activities, and COVID-19 testing, infection, and vaccination status. We developed a transmission-dynamic stochastic microsimulation parameterised by the California data and published literature. After an initial infection is introduced to a prison, the model evaluates the effect of various policy scenarios on infections and hospitalisations over 200 days. Scenarios vary by vaccine coverage, baseline immunity (0%, 25%, or 50%), resumption of activities, and use of non-pharmaceutical interventions (NPIs) that reduce transmission by 75%. We simulated five prison types that differ by residential layout and demographics, and estimated outcomes with and without repeated infection introductions over the 200 days.FindingsIf a viral variant is introduced into a prison that has resumed pre-2020 contact levels, has moderate vaccine coverage (ranging from 36% to 76% among residents, dependent on age, with 40% coverage for staff), and has no baseline immunity, 23–74% of residents are expected to be infected over 200 days. High vaccination coverage (90%) coupled with NPIs reduces cumulative infections to 2–54%. Even in prisons with low room occupancies (ie, no more than two occupants) and low levels of cumulative infections (ie, <10%), hospitalisation risks are substantial when these prisons house medically vulnerable populations. Risks of large outbreaks (>20% of residents infected) are substantially higher if infections are repeatedly introduced.InterpretationBalancing benefits of resuming activities against risks of outbreaks presents challenging trade-offs. After achieving high vaccine coverage, prisons with mostly one-to-two-person cells that have higher baseline immunity from previous outbreaks can resume in-person activities with low risk of a widespread new outbreak, provided they maintain widespread NPIs, continue testing, and take measures to protect the medically vulnerable.FundingHorowitz Family Foundation, National Institute on Drug Abuse, Centers for Disease Control and Prevention, National Science Foundation, Open Society Foundation, Advanced Micro Devices.

Numerical Investigation on the Thermal Performance of Three Advanced Micro Heat Pipes

Three micro heat pipes belonging to different types are selected as the research objects due to their lowest thermal resistance and the steadiest operation according to published literatures. They are the pulsating heat pipe with corrugated configuration (CPHP), the flat-plate heat pipe with eight microchannels (FPMHP) and the radial pulsating heat pipe (RPHP). A mathematical model common to the three micro heat pipes is built, and the maximum deviation between simulation and actual results is 16.1%. It is found that CPHP has the best heat transfer performance with the minimum thermal resistance of 1.14 K·W−1. Its average wall temperature and center-line velocity regularly oscillate after the start-up point. There is a pause phenomenon of motion for CPHP, and the pause period of motion decreases from 8.93 s to 7.25 s with the increasing input heat flux. RPHP possesses the most excellent temperature uniformity with the maximum axial temperature difference of 5.24 K. Furthermore, FPMHP is suitable for cooling temperature-resistant devices because its average wall temperature of evaporation section is the highest.

Functionalized Mesoporous Thin Films for Biotechnology.

Mesoporous materials bear great potential for biotechnological applications due to their biocompatibility and versatility. Their high surface area and pore interconnection allow the immobilization of molecules and their subsequent controlled delivery. Modifications of the mesoporous material with the addition of different chemical species, make them particularly suitable for the production of bioactive coatings. Functionalized thin films of mesoporous silica and titania can be used as scaffolds with properties as diverse as promotion of cell growth, inhibition of biofilms formation, or development of sensors based on immobilized enzymes. The possibility to pattern them increase their appeal as they can be incorporated into devices and can be tailored both with respect to architecture and functionalization. In fact, selective surface manipulation is the ground for the fabrication of advanced micro devices that combine standard micro/nanofluids with functional materials. In this review, we will present the advantages of the functionalization of silica and titania mesoporous materials deposited in thin film. Different functional groups used to modify their properties will be summarized, as well as functionalization methods and some examples of applications of modified materials, thus giving an overview of the essential role of functionalization to improve the performance of such innovative materials.

Comparative thermal performance evaluation of a heat sink based on geometrical and material amendments: A numerical study

The study focuses on the design and materialistic amendments for thermal performance evaluation of a heat sink which is a just modified version of the conventional heat sink used for processor Ryzen 5 3600, introduced by a company named Advanced Micro Devices (AMD) for cooling applications in High-Performance Gaming PCs. The enhancement of the cooling strategy is achieved within dimensional and cost constraints by modifying the parametric dimensions, increasing the surface area, and introducing metal to the air-fluid boundary layer aspects into it. In this study, the heat sink is designed with a core of cylindrical shape, keeping a height of 20 mm and a diameter of 90 mm. Also, the universal dimensional compatibility of this heat sink is considered for the performance evaluation, followed by design and angle of air-fin interaction, swapped center rectangle shape with a frustum to decrease the thermal hindrance and to increase the surface area without any increment in overall volume. Moreover, the fin density in the module of the heat sink has also been increased to enhance the convective heat transfer strategy from the surface. Both designing & simulation have been carried out on the FEM tool Autodesk Fusion 360 and based on the numerical investigation on the modified design as per the conventional design, although our design is much more complex to manufacture in the first place. It has been observed that the new design is capable of providing 64.23% convective heat dissipation from the surface as well as able to reduce 50.9% of CPU surface temperature in comparison to the existing design of heat sink.

Advanced Devices for Tumor Diagnosis and Therapy.

At present, tumor diagnosis is performed using common procedures, which are slow, costly, and still presenting difficulties in diagnosing tumors at their early stage. Tumor therapeutic methods also mainly rely on large-scale equipment or non-intelligent treatment approaches. Thus, an early and accurate tumor diagnosis and personalized treatment may represent the best treatment option for a successful result, and the efforts in finding them are still in progress and mainly focusing on non-destructive, integrated, and multiple technologies. These objectives can be achieved with the development of advanced devices and smart technology that represent the topic of the current investigations. Therefore, this review summarizes the progress in tumor diagnosis and therapy and briefly explains the advantages and disadvantages of the described microdevices, finally proposing advanced micro smart devices as the future development trend for tumor diagnosis and therapy.

Aerodynamic effects on an emulated hovering passerine with different wing-folding amplitudes

Bird flight involves complicated wing kinematics, especially during hovering flight. The detailed aerodynamic effects of wings with higher degrees of freedom (DOFs) remain to be further investigated. Therefore, we designed a novel multiarticulate flapping-wing robot with five DOFs on each wing. Using this robot we aimed to investigate the more complicated wing kinematics of birds, which are usually difficult to test and analyze. In this study the robot was programmed to mimic the previously observed hovering motion of passerines, and force measurements and particle image velocimetry experiments. We experimented with two different wing-folding amplitudes: one with a larger folding amplitude, similar to that of real passerines, and one with only half the amplitude. The robot kinematics were verified utilizing direct linear transformation, which confirmed that the wing trajectories had an acceptable correlation with the desired motion. According to the lift force measurements, four phases of the wingbeat cycle were characterized and elaborated through camera images and flow visualization. We found that the reduction in folding amplitude caused a higher negative force during upstrokes and also induced a greater positive force at the initial downstroke through ‘wake capture’. This could increase the vertical oscillation while hovering despite a minor increase in average force production. This phenomenon was not observed during forward flight in previous studies. Our results provide a critical understanding of the effect of wing folding which is required for designing the wing kinematics of future advanced flapping-wing micro aerial vehicles.

Strongly coupled partitioned iterative method for the structure–piezoelectric–circuit interaction using hierarchical decomposition

The key to the design of advanced micro electro–mechanical devices is an accurate evaluation of the circuit-integrated piezoelectric oscillator that accounts for its complicated configuration. Here, the direct numerical modeling of this oscillator leads to a general formulation as a structure–piezoelectric–circuit interaction. Hence, this study developed a strongly coupled partitioned iterative method for the structure–piezoelectric–circuit interaction. The proposed method was constructed using hierarchical decomposition, the partitioned iterative method for two coupled fields, and loop union. That is, the whole system of the coupled multiphysics is hierarchically decomposed into coupled two-field subsystems, partitioned iterative algorithms for two coupled fields are applied to these subsystems, and the coupling algorithms for these subsystems are reduced to a single coupling algorithm. In the proposed method, three distinct direct piezoelectric, inverse piezoelectric, and circuit solvers are strongly coupled with each other. The inverse piezoelectric solver uses shell finite elements to analyze the response of the thin oscillator efficiently, while the direct piezoelectric solver uses solid finite elements to accurately describe the three-dimensional distribution of the electric potential in the piezoelectric continuum. The proposed method can accurately analyze coupling phenomena in the RC circuit, piezoelectric shunt damping, and piezoelectric energy harvesting.

Effects of Heat Source Temperature, Nanostructure, and Wettability on Explosive Boiling of Ultra-Thin Liquid Argon Film Over Graphene Substrate: A Molecular Dynamics Study

Background: The study on explosive boiling phenomenon has received increasing attention because it involves many industries, such as advanced micro-, nano-electromechanical and nano-electronic cooling systems, laser steam cleaning, and so on. Objective: In the present work, the explosive boiling of ultra-thin liquid film over two-dimensional nanomaterial surface in confined space with particular emphasis under the three different influencing factors: various heights of nanostructures, various wetting conditions of solid-liquid interface as well as various heat source temperatures. Methods: Molecular Dynamics simulations (MDs) in present work have been adopted to simulate the whole explosive boiling process. Results: For different heat source temperature case, the higher the heat temperature is, the less time the explosive boiling spends after relaxation. For nanostructure case, nanostructure surface significantly increases heat transfer rate and then leads to the increase of phase transition rate of explosive boiling. For different wetting property case, the increase of surface wettability results in an increase of phase transition to some degree. Conclusion: The addition of nanostructures, the higher heat source temperature and good wettability between thin liquid film and substrate surface dramatically improve thermal heat transfer from solid surface to liquid film, which will give rise to explosive boiling occur. In addition, the non-vaporized argon layer still exists in these three factors despite continuous thermal transmission from the substrate surface to liquid argon film adjacent to the solid surface even other vaporized argon atoms.

Next Generation Cell Culture Tools Featuring Micro‐ and Nanotopographies for Biological Screening

AbstractCells can perceive complex mechanical cues across both the micro‐ and nanoscale which can influence their development. While causative effects between surface topography and cellular function can be demonstrated, the variability in materials used in this screening process makes it difficult to discern whether the observed phenotypic changes are indeed a result of topographical cues alone or the inherent difference in material properties. A novel approach to directly imprint micro‐ and nanoscaled topographical features into the base of conventional cell cultureware is thus developed, facilitating its compatibility with standard biological techniques and methods of analysis. The utility of this technology is demonstrated by performing high‐throughput screening across five distinct cell types to interrogate the effects of 12 surface topographies, exemplifying unique cell‐specific responses to both behavior and cell morphological characteristics. The ability of this technology to underpin new insights into how surface topographies can regulate key image descriptors to drive cell fate determination is further demonstrated. These findings will inform the future development of advanced micro‐ and nanostructured cell culture substrates that can regulate cell behavior and fate determination across the life sciences, including fundamental cell biology, drug screening, and cell therapy.

Numerical modeling of welded wide flange fuses

Welded wide flange fuse (WWFF) is a simple metallic yielding damper which utilizes commonly available welded wide flange sections to dissipate energy through shear yielding of the steel web in the longitudinal direction. The use of welded plates makes the fabrication of WWFF simple and versatile. In this paper, advanced numerical micro- and macro- models are developed for WWFF. The models are validated using experimental results. The micro-model was developed using a thin shell finite element model. This model was used to assess the behavior of WWFFs with various slenderness and aspect ratios that were not tested experimentally. Key design parameters such as yielding force, initial stiffness, ultimate force, and ultimate deformation were simulated. The results show the WWFF has a predictable and stable hysteretic response. Since micro-models are often computationally too intensive for engineering applications, a macro-model was developed using the data from the experimental test. The hysteresis of the macro-model was also verified against the micro-model. The results show that the macro model can be used to simulate the hysteresis response of the WWFF. Hence, it can be used efficiently to analyze the nonlinear dynamic response of the structures utilizing WWFF.

Shape Memory Alloys and Polymers for MEMS/NEMS Applications: Review on Recent Findings and Challenges in Design, Preparation, and Characterization

Rapid progress in material science and nanotechnology has led to the development of the shape memory alloys (SMA) and the shape memory polymers (SMP) based functional multilayered structures that, due to their capability to achieve the properties not feasible by most natural materials, have attracted a significant attention from the scientific community. These shape memory materials can sustain large deformations, which can be recovered once the appropriate value of an external stimulus is applied. Moreover, the SMAs and SMPs can be reprogrammed to meet several desired functional properties. As a result, SMAs and SMPs multilayered structures benefit from the unprecedented physical and material properties such as the shape memory effect, superelasticity, large displacement actuation, changeable mechanical properties, and the high energy density. They hold promises in the design of advanced functional micro- and nano-electro-mechanical systems (MEMS/NEMS). In this review, we discuss the recent understanding and progress in the fields of the SMAs and SMPs. Particular attention will be given to the existing challenges, critical issues, limitations, and achievements in the preparation and characterization of the SMPs and NiTi-based SMAs thin films, and their heterostructures for MEMS/NEMS applications including both experimental and computational approaches. Examples of the recent MEMS/NEMS devices utilizing the unique properties of SMAs and SMPs such as micropumps, microsensors or tunable metamaterial resonators are highlighted. In addition, we also introduce the prospective future research directions in the fields of SMAs and SMPs for the nanotechnology applications.

Stretching a Polymer Chain in a Confined Space

The quantitative characterization of micromechanical properties of polymer biomaterials and the development of advanced biological micro-/nano- technology and devices need to quantitatively analyze the statistical thermodynamic properties and behaviors of polymer chains such as biological macromolecules in complex microenvironment. In the process of achieving this goal, the cross research of continuum mechanics and statistical thermodynamics plays a very important role. Aiming at the mechanics problems in this field, starting from the force stretching of DNA molecules, and by introducing several theoretical models describing the statistical thermodynamic properties of polymer chains, it is pointed out that the wormlike chain model has more significant advantages in describing the relationship between force and configuration change of semi-flexible polymer chains than other ideal random chain models, so that the qualitative and quantitative understanding of the statistical thermodynamic properties and behavior of polymers in complex microenvironment has become largely dependent on the relevant research progresses based on the wormlike chain model. Based on this fact, by reviewing the research on the influence of geometric constraints on the random conformation distribution of polymer chains, the research on the statistical thermodynamic model of polymer chains under the simultaneous action of tension and constraints, and the simulation research on the statistical physical properties of polymer chains based on high-performance computers, the latest progress and challenging problems in the research of statistical thermodynamic properties and behavior of worm chains under different constraints and stress microenvironments are summarized. Finally, through summary and analysis, it is pointed out that the study of statistical thermodynamics of worm chain in complex microenvironment is an important basis for understanding life phenomena from the molecular and cell scale, developing advanced micro- and nano- technology and constructing the constitutive relationship of soft matter. At present, it has become a very challenging frontier topic in the interdisciplinary of mechanics.

Discovery, Arbitration, and 28 U.S.C. §1782: Rules or Standards?

This paper is a draft for one of the chapters for Professor Silberman’s book on private international law: “The Counter-Revolution in Private International Law in the United States: From Standards to Rules? The book will be based on her Hague Academy General Course Lectures to be given remotely in summer 2021. This particular paper explores the tensions between standards and rule as it relates to U.S. judicial assistance for use in a “foreign or international tribunal”, as provided for in 28 U.S.C. § 1782. Professor Silberman traces the history of § 1782 and discusses the first and only Supreme Court decision, Intel Corpo. v. Advanced Micro Devices. Inc., interpreting the statute. She then focuses on the question of whether a “foreign or international tribunal” under § 1782 includes private commercial arbitration, an issue before the Court in Servotronics, Inc. v. Rolls-Royce PLC to be argued next term. Professor Silberman highlights the Circuit split on this issue and surveys the competing arguments on both sides. Referencing arbitration specific statutes in other jurisdiction, Professor Silberman observes a distinction between judicial assistance for discovery purposes and for use in a plenary proceeding. Professor Silberman suggests that “rules” rather than “standards” would be preferable in the arbitration context and suggests a legislative solution to create such rules.

ТЕНДЕНЦІЇ ТА ДИНАМІКА РОЗВИТКУ СВІТОВОГО ТОВАРНОГО РИНКУ ПРОДУКЦІЇ МАШИНОБУДУВАННЯ

Today’s world economy is characterized by a high rate of world production and international trade in machinery and technical equipment and by intensive structural changes in the world market. The engineering industry in our days is the most important industry in any country, reflecting the population’s abundance, the economy’s ability to adapt to the international market, and the country’s ability to keep up with dynamic developing technologies. The subject of the article is relevant, since, in the current economic environment, the engineering industry is the key to successful and profitable foreign trade. The development of mechanical engineering has a positive impact on many parallel sectors of the country’s economy. Nowadays, engineering plays a key role in the diffusion of innovative machines, equipment and manufacturing processes in other sectors of the economy. The majority of biotechnologies and nanotechnologies, production of advanced materials, micro and photo electronics, is heavily dependent on innovation in mechanical engineering. The USA, Japan, Germany, and China are among the world’s leading exports of machinery and technology. In the past 20 years, the leaders have been replaced three times. There has been a recent upward tendency to China’s mechanical engineering market grows. The global competition among the world’s leading regions is about to intensify correspondingly. Overall trend in the world economy is the relocation of low- and medium-scale industries from developed to developing countries. Multinational companies contribute significantly to this process. Experts are predicting that the developing countries will be further strengthened in the global engineering industry over the medium term. Above all this concerns China. The development of mechanical engineering was greatly influenced by the coronavirus pandemic. The current challenges are related to the pandemic, represent an important additional negative factor for the industry that has already been hit, and continue to face challenges due to the shrinking of leading markets and due to need for large-scale investment in machinery and technology. Resumption of economic growth in the countries most affected by the pandemic takes place on an investment basis, and it is going to be supported by the accumulation of business finance, that would be stimulate further investments primarily in the field of machine engineering.

Biocarbon reinforced polypropylene composite: An investigation of mechanical and filler behavior through advanced dynamic atomic force microscopy and X-ray micro CT

Polymer composites were manufactured using biocarbon particles as a reinforcing filler to improve the mechanical and thermal properties. However, a detailed examination of dispersion and agglomeration of filler is essential to correlate the filler matrix and the filler and filler interactions with the mechanical properties of the product. We investigated the variations of mechanical, agglomeration behaviour of fillers, and thermal properties of polypropylene coconut shell biocarbon composites. PP CSB composites were prepared by melt mixing process varying the CSB content using a Brabender mixer. The nanomechanical mapping of the composites studied using Atomic Force Microscopy revealed an increase in Youngs modulus from 1.6 to 2.9 GPa when CSB loading increased from 0 to 20 weight percentage. The dispersion and agglomeration of CSB filler in the PP matrix were investigated using 3D reconstructed images with the help of X-ray micro CT, and a dedicated 3D reconstruction software. The thermal stability of the PP CSB composites also improved with an increase in CSB content in PP.