Optimization Of Technology And Design Parameters Of IGBT Using TWB

1997 ◽  
Vol 483 ◽  
Author(s):  
B. Fatemizadehl ◽  
Y. Granik
Keyword(s):  
Cost Effective ◽  
Design Parameters ◽  
Response Surface Modeling ◽  
Two Dimensional ◽  
Trade Off ◽  
Design Alternatives ◽  
Cost Effective Approach ◽  
Different Types ◽  
The Impact ◽  
Technology And Design

AbstractThis paper presents a methodology to optimize the design of different types of IGBT using TWB (TMA WorkBench). Using RSM (Response Surface Modeling) and DOE (Design of Experiment) in TWB we have developed a methodology, which can be applied to explore the impact of design modifications on the speed improvement and study the trade-off between speed, on-resistance, and breakdown voltage of IGBT. This method is a rapid and cost-effective approach for studying design alternatives. Two-dimensional simulations were used to determine the influence of technology and design parameter on device characteristics.

Analytic Optimization of Cost Effective Thermoelectric Generation on Top of Rankine Cycle

2013 ◽  
Author(s):  
Kazuaki Yazawa ◽  
Yee Rui Koh ◽  
Ali Shakouri
Keyword(s):  
Steam Turbine ◽  
Fuel Efficiency ◽  
Cost Effective ◽  
Rankine Cycle ◽  
Energy Conversion Efficiency ◽  
Design Parameters ◽  
Steam Temperature ◽  
Combined System ◽  
Fuel Consumption Rate ◽  
The Impact

Thermoelectric (TE) generators have a potential advantage of the wide applicable temperature range by a proper selection of materials. In contrast, a steam turbine (ST) as a Rankine cycle thermodynamic generator is limited up to more or less 630 °C for the heat source. Unlike typical waste energy recovery systems, we propose a combined system placing a TE generator on top of a ST Rankine cycle generator. This system produces an additional power from the same energy source comparing to a stand-alone steam turbine system. Fuel efficiency is essential both for the economic efficiency and the ecological friendliness, especially for the global warming concern on the carbon dioxide (CO2) emission. We report our study of the overall performance of the combined system with primarily focusing on the design parameters of thermoelectric generators. The steam temperature connecting two individual generators gives a trade-off in the system design. Too much lower the temperature reduces the ST performance and too much higher the temperature reduces the temperature difference across the TE generator hence reduces the TE performance. Based on the analytic modeling, the optimum steam temperature to be designed is found near at the maximum power design of TE generator. This optimum point changes depending on the hours-of-operation. It is because the energy conversion efficiency directly connects to the fuel consumption rate. As the result, physical upper-limit temperature of steam for ST appeared to provide the best fuel economy. We also investigated the impact of improving the figure-of-merit (ZT) of TE materials. As like generic TE engines, reduction of thermal conductivity is the most influential parameter for improvement. We also discuss the cost-performance. The combined system provides the payback per power output at the initial and also provides the significantly better energy economy [$/KWh].

Quantitative Selection of Variation Reduction Plans

1998 ◽  
Author(s):  
Anna C. Thornton
Keyword(s):  
Risk Mitigation ◽  
Cost Effective ◽  
Variation Reduction ◽  
Multiple Quality Characteristics ◽  
Cost Effective Approach ◽  
Manufacturing Performance ◽  
The Impact ◽  
Manufacturing Variation ◽  
Selection Of

Abstract Quality has been a rallying call in the design and manufacturing world for the last two decades. One way to improve quality is to reduce the impact of manufacturing variation. Variation risk mitigation is challenging especially when a product has multiple quality characteristics and complex production and assembly. It is common wisdom that companies should identify and mitigate the risk associated with variation throughout the design process. As yield problems are identified, they should be mitigated using the most cost effective approach. One approach to variation risk mitigation is variation reduction (VR). VR targets reduction of variation introduced by existing manufacturing processes using tools such as Design of Experiments (DOE) and robust design. Many companies have specialized groups that specialize in these methods. VR teams have the role of improving manufacturing performance; however, these teams are limited in their resources. In addition, no tools exist to quantitatively determine where a VR team’s efforts are most effectively deployed. This paper provides a mathematical and optimization model to best allocate VR resources in a complex product.

FORMATION OF COMBINED SURFACE FEATURES OF PROTRUSION ARRAY AND WRINKLES ATOP SHAPE-MEMORY POLYMER

2009 ◽  
Vol 16 (06) ◽  
pp. 929-933 ◽  
Author(s):  
L. SUN ◽  
Y. ZHAO ◽  
W. M. HUANG ◽  
T. H. TONG
Keyword(s):  
Shape Memory ◽  
Shape Memory Polymer ◽  
Polymer Surface ◽  
Cost Effective ◽  
Gold Layer ◽  
Surface Features ◽  
Cost Effective Approach ◽  
Different Types ◽  
Sputter Deposited ◽  
Steel Balls

We demonstrate a simple and cost-effective approach to realize two combined surface features of different scales together, namely submillimeter-sized protrusion array and microwrinkles, atop a polystyrene shape-memory polymer. Two different types of protrusions, namely flat-top protrusion and crown-shaped protrusion, were studied. The array of protrusions was produced by the Indentation-Polishing-Heating (IPH) process. Compactly packed steel balls were used for making array of indents. A thin gold layer was sputter deposited atop the polymer surface right after polishing. After heating for shape recovery, array of protrusions with wrinkles on the top due to the buckling of gold layer was produced.

scholarly journals Rheometer enabled study of cartilage frequency-dependent properties

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Stefano Perni ◽  
Polina Prokopovich
Keyword(s):  
Applied Load ◽  
Cost Effective ◽  
Constant Load ◽  
Hydraulic Permeability ◽  
Frequency Dependent ◽  
Shear Moduli ◽  
Tissue Replacement ◽  
Cost Effective Approach ◽  
The Impact

AbstractDespite the well-established dependence of cartilage mechanical properties on the frequency of the applied load, most research in the field is carried out in either load-free or constant load conditions because of the complexity of the equipment required for the determination of time-dependent properties. These simpler analyses provide a limited representation of cartilage properties thus greatly reducing the impact of the information gathered hindering the understanding of the mechanisms involved in this tissue replacement, development and pathology. More complex techniques could represent better investigative methods, but their uptake in cartilage research is limited by the highly specialised training required and cost of the equipment. There is, therefore, a clear need for alternative experimental approaches to cartilage testing to be deployed in research and clinical settings using more user-friendly and financial accessible devices. Frequency dependent material properties can be determined through rheometry that is an easy to use requiring a relatively inexpensive device; we present how a commercial rheometer can be adapted to determine the viscoelastic properties of articular cartilage. Frequency-sweep tests were run at various applied normal loads on immature, mature and trypsinased (as model of osteoarthritis) cartilage samples to determine the dynamic shear moduli (G*, G′ G″) of the tissues. Moduli increased with increasing frequency and applied load; mature cartilage had generally the highest moduli and GAG depleted samples the lowest. Hydraulic permeability (KH) was estimated from the rheological data and decreased with applied load; GAG depleted cartilage exhibited higher hydraulic permeability than either immature or mature tissues. The rheometer-based methodology developed was validated by the close comparison of the rheometer-obtained cartilage characteristics (G*, G′, G″, KH) with results obtained with more complex testing techniques available in literature. Rheometry is relatively simpler and does not require highly capital intensive machinery and staff training is more accessible; thus the use of a rheometer would represent a cost-effective approach for the determination of frequency-dependent properties of cartilage for more comprehensive and impactful results for both healthcare professional and R&D.

Model Predictive Engine Speed Control for Transmissions With Dog Clutches

2016 ◽  
Author(s):  
Qilun Zhu ◽  
Robert Prucka ◽  
Michael Prucka ◽  
Hussein Dourra
Keyword(s):  
Engine Speed ◽  
Speed Control ◽  
Cost Effective ◽  
Combustion Stability ◽  
Design Parameters ◽  
Shift Quality ◽  
Engine Model ◽  
Prediction Horizon ◽  
Indicated Mean Effective Pressure ◽  
The Impact

The need for cost-effective fuel economy improvements has driven the introduction of automatic transmissions with an increasing number of gear ratios. Incorporation of interlocking dog clutches in these transmissions decreases package space and increases efficiency, as compared to conventional dry or wet clutches. Unlike friction based clutches, interlocking dog clutches require very precise rotational speed matching prior to engagement. Precise engine speed control is therefore critical to maintaining high shift quality. This research focuses on controlling the engine speed during a gearshift period by manipulating throttle position and combustion phasing. Model predictive control (MPC) is advantageous in this application since the speed profile of a future prediction horizon is known with relatively high confidence. The MPC can find the optimal control actions to achieve the designated speed target without invoking unnecessary actuator manipulation and violating hardware and combustion constraints. This research utilizes linear parameter varying (LPV) MPC to control the engine speed during the gearshift period. Combustion stability constraints are considered with a control oriented covariance of indicated mean effective pressure model (COV of IMEP). The proposed MPC engine speed controller is validated with a high-fidelity 0-dimensional engine model with crank angle resolution. Four case studies, based on simulation, investigate the impact of different MPC design parameters. They also demonstrate that the proposed MPC engine controller successfully achieves the speed reference tracking objective while considering combustion variation constraints.

Active Torsion Bar Body Roll Minimization System: Design and Testing

2003 ◽  
Author(s):  
David Cimba ◽  
Kyle Gilbert ◽  
John Wagner
Keyword(s):  
Cost Effective ◽  
Vehicle Body ◽  
Design Parameters ◽  
Test Environment ◽  
Component Design ◽  
Body Roll ◽  
And Performance ◽  
Emergency Scenarios ◽  
The Impact ◽  
Torsion Bar

Sport utility and light-duty commercial vehicles exhibit a higher propensity for rollover during aggressive driving maneuvers, emergency scenarios, and degraded environmental conditions. A variety of strategies have been proposed to reduce vehicle body roll including active suspensions, comprehensive yaw stability systems, and active torsion bars. The active torsion bar systems have recently gained popularity due to their cost effective design and adaptability to existing chassis systems. However, the development of new control algorithms, design of subsystem components, and the evaluation of parameter sensitivity via testing a full scale vehicle is not always practical due to cost and safety concerns. Thus, a modular simulation tool and bench top testing environment is required to facilitate design and performance studies. In this paper, a series of mathematical models will be introduced to describe the vehicle dynamics and the roll prevention system. Representative numerical results are discussed to investigate a vehicle’s transient response with and without an active torsion bar system, as well as the impact of torsion bar and hydraulic component design parameters. Finally, a hardware in-the-loop test environment will be presented.

Role of Microorganisms in Bioremediation

2021 ◽  
Vol 2 (2) ◽  
pp. 140-176
Author(s):  
Komal Aslam ◽  
Hafiza Iqra Saeed ◽  
Jessica Alyas ◽  
Aysha Saeed ◽  
Tanveer Majeed ◽  
...  
Keyword(s):  
Organic Pollutants ◽  
Cost Effective ◽  
Industrial Contaminants ◽  
Optimal Functioning ◽  
Cost Effective Approach ◽  
Different Types ◽  
Living Organisms

Bioremediation involves the use of natural microorganisms for the purpose ofdegrading numerous types of industrial and environmental waste. Microorganismsrequire carbon, nutrients, and energy to live and multiply as all living organisms do. Inorder to obtain energy, such microorganisms break down organic pollutants into simplerorganic compounds like carbon, salts, water, and similar harmless products. Thisapproach of degrading contaminants using microorganisms has proved much beneficialand has been proven to be cost-effective and efficient. There are a lot of naturally occurringmicroorganisms that have been reported essential in the degradation of organic pollutants.Different industries use different types of bioremediation methods. Specificenvironmental conditions may be required for optimal functioning of microbes e.g., pH,temperature, humidity, etc. Bioremediation has been proven as an environment-friendlyand cost-effective approach to deal with industrial contaminants. Descriptive informationof microbes involved in bioremediation has been explained in this review.

Investigating the effects of COVID-19 to crime rates through a geospatial approach: the case of New York, USA

2021 ◽  
Author(s):  
Ioanna Tselka ◽  
Isidora Isis Demertzi ◽  
George P. Petropoulos
Keyword(s):  
New York ◽  
Scientific Evidence ◽  
Cost Effective ◽  
Crime Rates ◽  
Added Value ◽  
Web Gis ◽  
Study Region ◽  
Cost Effective Approach ◽  
Before And After ◽  
The Impact

<p>Covid-19 pandemic has led to severe consequences to humanity worldwide. Yet, to our knowledge, little scientific evidence is available exploring the impact of the pandemic on criminality. Thus, it is imperative to examine their relationships spatially to obtain a better understanding of societal characteristics during the pandemic.</p><p>This study aims at demonstrating the use of geoinformation in analyzing the spatial patterns between crime properties and Covid-19 spread using as a case study New York City, USA, one of the largest metropolitan cities of the world. To address our objectives, geostatistical analysis and data visualization methods have been implemented in real-world crime data acquired from a web-GIS platform. Our analysis concerns two equal time periods before and after the lockdown implementation.</p><p>Results revealed some very interesting patterns spatially between the examined parameters and societal characteristics existing in the study region. The methodological framework presented underlined the added value of geoinformation as a robust and cost-effective approach in examining the impact of the pandemic to the society.</p><p> </p><p><strong>Keywords:</strong> Covid-19, pandemic, crime rates, geoinformation, New York</p>

scholarly journals Environmental DNA and metabarcoding for the study of amphibians and reptiles: species distribution, the microbiome, and much more

2019 ◽  
Vol 40 (2) ◽  
pp. 129-148 ◽  
Author(s):  
Gentile Francesco Ficetola ◽  
Raoul Manenti ◽  
Pierre Taberlet
Keyword(s):  
Environmental Dna ◽  
Cost Effective ◽  
Diet Analysis ◽  
Limited Attention ◽  
Target Species ◽  
Cost Effective Approach ◽  
Analytical Strategies ◽  
Complex Relationships ◽  
The Impact ◽  
Analytical Complexity

Abstract In the last decade, eDNA and metabarcoding have opened new avenues to biodiversity studies; amphibians and reptiles are animals for which these new approaches have allowed great leaps forward. Here we review different approaches through which eDNA can be used to study amphibians, reptiles and many more organisms. eDNA is often used to evaluate the presence of target species in freshwaters; it has been particularly useful to detect invasive alien amphibians and secretive or rare species, but the metabarcoding approach is increasingly used as a cost-effective approach to assess entire communities. There is growing evidence that eDNA can be also useful to study terrestrial organisms, to evaluate the relative abundance of species, and to detect reptiles. Metabarcoding has also revolutionized studies on the microbiome associated to skin and gut, clarifying the complex relationships between pathogens, microbial diversity and environmental variation. We also identify additional aspects that have received limited attention so far, but can greatly benefit from innovative applications of eDNA, such as the study of past biodiversity, diet analysis and the reconstruction of trophic interactions. Despite impressive potential, eDNA and metabarcoding also bear substantial technical and analytical complexity; we identify laboratory and analytical strategies that can improve the robustness of results. Collaboration among field biologists, ecologist, molecular biologists, and bioinformaticians is allowing fast technical and conceptual advances; multidisciplinary studies involving eDNA analyses will greatly improve our understanding of the complex relationships between organisms, and our effectiveness in assessing and preventing the impact of human activities.

scholarly journals Analytical Breakdown Voltage Model for Partial SOI-LDMOS Transistor with Buried Oxide Step Structure

2021 ◽  
Author(s):  
Jagamohan Sahoo ◽  
Rajat Mahapatra
Keyword(s):  
Electric Field ◽  
Analytical Model ◽  
Breakdown Voltage ◽  
Point Of View ◽  
Silicon On Insulator ◽  
Oxide Semiconductor ◽  
Design Parameters ◽  
Drift Region ◽  
Two Dimensional ◽  
The Impact

Abstract We have developed a simple physics-based two-dimensional analytical Off-state breakdown voltage model of a PBOSS Silicon-On-Insulator Lateral Diffused Metal Oxide Semiconductor (SOI-LDMOS) transistor. The analytical model includes the expressions of surface potential and electric field distributions in the drift region by solving the 2D Poisson’s equation. The electric field at the Si-SiO2 surface is modified by creating additional electric field peaks due to the presence of the PBOSS structure. The uniformly distributed electric field results in improving the breakdown voltage. Further, the breakdown voltage is analytically obtained via critical electric field concept to quantify the breakdown characteristic. The model exploits the impact of the critical device design parameters such as thickness and length of the PBOSS structure, doping, and thickness of the drift region on the surface electric field and the breakdown voltage. The proposed model is verified by the results obtained from ATLAS two dimensional simulations. The analytical model is of the high potential from a physical and mathematical point of view to design high voltage SOI-LDMOS transistors for power switching applications.

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