NEW COLLECTOR OF PLANAR INSULATED GATE BIPOLAR TRANSISTOR FOR BROAD APPLICATIONS

A new concept of Insulated Gate Bipolar Transisitor (IGBT) with a Si/Ge layer collector is proposed to meet different requirements for turn-on voltage and turn-off time. The operation principles of IGBT are discussed and the energy band diagram of Si/Ge heterojunction is employed to explain the inner dynamic mechanism of the proposed IGBT. Two-dimensional (2D) device-circuit mixed-mode simulations indicate that the tail-current, which is a major cause of the power loss and limits the operation speed of the device, is suppressed effectively by using the Si/Ge layer collector. On the other hand, turn-on voltage is increased by the use of the Si/Ge collector. Furthermore, the turn-on voltage is increasing with the increase of the areal rate of the Ge region in the whole collector, while the turn-off time is reversed. This valuable information leads to the freely tunable planar IGBT by adapting the different areal rates of the Ge region to cast to different actual situations. Detailed physical explanations are also given.

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A High Precision IGBT Macro-Model for Switching Simulations

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.698.109 ◽

2016 ◽

Vol 698 ◽

pp. 109-117

Author(s):

Masaki Kazumi ◽

Hitoshi Aoki ◽

Yukiko Arai ◽

Shunichiro Todoroki ◽

Takuya Totsuka ◽

...

Keyword(s):

High Power ◽

Source Code ◽

Small Signal ◽

Electrical Circuits ◽

Macro Model ◽

Insulated Gate Bipolar Transistor ◽

Turn On ◽

Spice Model ◽

Test Circuit ◽

Off Time

In this research, a novel SPICE model of an Insulated-Gate-Bipolar-Transistor (IGBT), which is often used to handle high power signals in automotive electrical circuits, has been developed. The model consists of basic SPICE elements. Thus, it can be used in any SPICE-compatible simulators without any source code modification. This paper presents the results of DC, small signal AC, and transient characteristics considering the temperature dependence by using the proposed IGBT macro-model for SPICE. In addition, turn-on and -off time verifications are presented by using a switching test circuit provided by an IGBT manufacturer.

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Differential conservation of histone 2A variants between mammals and sea urchins.

The Journal of Cell Biology ◽

10.1083/jcb.93.2.426 ◽

1982 ◽

Vol 93 (2) ◽

pp. 426-431 ◽

Cited By ~ 20

Author(s):

R S Wu ◽

D Nishioka ◽

W M Bonner

Keyword(s):

Sea Urchin ◽

Tryptic Peptide ◽

Sea Urchins ◽

Strongylocentrotus Purpuratus ◽

The Other ◽

Its Sequence ◽

Two Dimensional ◽

Selective Pressures ◽

Turn On ◽

L1210 Cells

The histone 2A proteins of the sea urchin Strongylocentrotus purpuratus are compared with those of the mouse. While the major H2As in these two organisms do not comigrate on two-dimensional gels, the sea urchin contains a protein that comigrates with the minor histone 2A variant H2A.Z from mammals. H2A.Z is of particular interest because its sequence homology with other H2As is quite low, and it is not phosphorylated as are other H2As. A comparison of the tryptic peptide patterns of several H2As from sea urchin blastulae and mouse L1210 cells show that, while the patterns of the H2A.Zs differ greatly from the patterns of the other H2As, the patterns of the mouse and sea urchin H2A.Zs are very similar. Since the H2A.Zs have only one or two peptides in common with the other H2As, the conservation of their sequence indicates that H2A.Zs have evolved under somewhat different selective pressures from other H2As. Unlike all the other sea urchin H2As whose syntheses either turn on or off during early development, H2A.Z seems to be synthesized continuously throughout this period.U

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Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180045 ◽

1990 ◽

Vol 48 (1) ◽

pp. 258-259

Author(s):

J.L. Carrascosa ◽

G. Abella ◽

S. Marco ◽

M. Muyal ◽

J.M. Carazo

Keyword(s):

Three Dimensional ◽

The Other ◽

Two Dimensional ◽

Series Method ◽

Three Dimensional Reconstruction ◽

Structural Components ◽

E Coli ◽

Dimensional Reconstruction ◽

Morphogenetic Factors ◽

Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

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Polymer-Graphene Nanoassemblies and their Applications in Cancer Theranostics

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520619666191028112258 ◽

2020 ◽

Vol 20 (11) ◽

pp. 1340-1351 ◽

Cited By ~ 1

Author(s):

Ponnurengam M. Sivakumar ◽

Matin Islami ◽

Ali Zarrabi ◽

Arezoo Khosravi ◽

Shohreh Peimanfard

Keyword(s):

Mechanical Stability ◽

Chemical Properties ◽

The Other ◽

Hydrophilic Polymer ◽

Two Dimensional ◽

Normal Tissues ◽

Physical Chemical ◽

Anti Cancer ◽

Good Biocompatibility ◽

Cancer Theranostics

Background and objective: Graphene-based nanomaterials have received increasing attention due to their unique physical-chemical properties including two-dimensional planar structure, large surface area, chemical and mechanical stability, superconductivity and good biocompatibility. On the other hand, graphene-based nanomaterials have been explored as theranostics agents, the combination of therapeutics and diagnostics. In recent years, grafting hydrophilic polymer moieties have been introduced as an efficient approach to improve the properties of graphene-based nanomaterials and obtain new nanoassemblies for cancer therapy. Methods and results: This review would illustrate biodistribution, cellular uptake and toxicity of polymergraphene nanoassemblies and summarize part of successes achieved in cancer treatment using such nanoassemblies. Conclusion: The observations showed successful targeting functionality of the polymer-GO conjugations and demonstrated a reduction of the side effects of anti-cancer drugs for normal tissues.

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The New Historicism

10.1093/oso/9780198810315.003.0002 ◽

2018 ◽

Author(s):

Marjorie Levinson

Keyword(s):

Dialectical Materialism ◽

The Other ◽

New Historicism ◽

Turn On ◽

The World ◽

Previous Decade ◽

Critical Turn ◽

The Relationship

Chapter 2 studies the relationship between historicism and Romanticism. It locates the two between Enlightenment materialism, on one side, and Marxian historical and dialectical materialism, on the other. In so doing, it isolates a paradox of materialism—namely, its production of the very concepts that undo it. These include the ideas of knowing as dissociated conceptual activity, and consciousness as absolute negativity. Romanticism and historicism, it is argued, represent solutions to a common problem—a claim defended through a reading of Wordsworth’s sonnet “The world is too much with us.” In considering how we position ourselves in relation to past literature, the chapter evaluates the choices between contemplation and empathy, knowledge and power, blame and defense. As such, it represents the first move in a self-critical turn on the new historicist method that had shaped the author’s—and part of the field’s—work in the previous decade.

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To Analyze Energy Band Diagram of N-Tunnel Field Effect Transistors (NTFET)

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1033/1/012042 ◽

2021 ◽

Vol 1033 ◽

pp. 012042

Author(s):

Rajeev Bhatia ◽

S.S. Gill

Keyword(s):

Energy Band ◽

Field Effect ◽

Field Effect Transistors ◽

Energy Band Diagram ◽

Band Diagram

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On the Kirchhoff-Love Hypothesis (Revised and Vindicated)

Journal of Elasticity ◽

10.1007/s10659-021-09819-7 ◽

2021 ◽

Author(s):

Olivier Ozenda ◽

Epifanio G. Virga

Keyword(s):

Free Energy ◽

Dimension Reduction ◽

Three Dimensional ◽

Energy Functional ◽

The Other ◽

Variational Model ◽

Two Dimensional ◽

Elastic Plates ◽

Kinematic Constraint ◽

Free Energy Functional

AbstractThe Kirchhoff-Love hypothesis expresses a kinematic constraint that is assumed to be valid for the deformations of a three-dimensional body when one of its dimensions is much smaller than the other two, as is the case for plates. This hypothesis has a long history checkered with the vicissitudes of life: even its paternity has been questioned, and recent rigorous dimension-reduction tools (based on standard $\varGamma $ Γ -convergence) have proven to be incompatible with it. We find that an appropriately revised version of the Kirchhoff-Love hypothesis is a valuable means to derive a two-dimensional variational model for elastic plates from a three-dimensional nonlinear free-energy functional. The bending energies thus obtained for a number of materials also show to contain measures of stretching of the plate’s mid surface (alongside the expected measures of bending). The incompatibility with standard $\varGamma $ Γ -convergence also appears to be removed in the cases where contact with that method and ours can be made.

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Long way to Ricci flatness

Journal of High Energy Physics ◽

10.1007/jhep10(2020)059 ◽

2020 ◽

Vol 2020 (10) ◽

Author(s):

Jin Chen ◽

Chao-Hsiang Sheu ◽

Mikhail Shifman ◽

Gianni Tallarita ◽

Alexei Yung

Keyword(s):

Sigma Model ◽

Ultra Violet ◽

The Other ◽

Target Space ◽

Linear Sigma Model ◽

Close Relative ◽

Two Dimensional ◽

World Sheet ◽

Ricci Flat ◽

The World

Abstract We study two-dimensional weighted $$ \mathcal{N} $$ N = (2) supersymmetric ℂℙ models with the goal of exploring their infrared (IR) limit. 𝕎ℂℙ(N,$$ \tilde{N} $$ N ˜ ) are simplified versions of world-sheet theories on non-Abelian strings in four-dimensional $$ \mathcal{N} $$ N = 2 QCD. In the gauged linear sigma model (GLSM) formulation, 𝕎ℂℙ(N,$$ \tilde{N} $$ N ˜ ) has N charges +1 and $$ \tilde{N} $$ N ˜ charges −1 fields. As well-known, at $$ \tilde{N} $$ N ˜ = N this GLSM is conformal. Its target space is believed to be a non-compact Calabi-Yau manifold. We mostly focus on the N = 2 case, then the Calabi-Yau space is a conifold. On the other hand, in the non-linear sigma model (NLSM) formulation the model has ultra-violet logarithms and does not look conformal. Moreover, its metric is not Ricci-flat. We address this puzzle by studying the renormalization group (RG) flow of the model. We show that the metric of NLSM becomes Ricci-flat in the IR. Moreover, it tends to the known metric of the resolved conifold. We also study a close relative of the 𝕎ℂℙ model — the so called zn model — which in actuality represents the world sheet theory on a non-Abelian semilocal string and show that this zn model has similar RG properties.

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