Physical Design Fundamentals of High-Performance Avalanche Heterophotodiodes with Separate Absorption and Multiplication Regions

Fully ceramic microencapsulated fuel (FCM) is employed in the supercritical CO2 (S-CO2)-cooled reactor as accident tolerant fuel (ATF). Although the fuel and the assembly substrate contain SiC, the assembly cannot be sufficiently moderated due to the weak moderating performance of S-CO2, which affects the neutronics economy seriously. In this study, a new fuel assembly based on FCM fuel is proposed for the S-CO2 cooled reactor. Besides, the solid moderator rod is introduced into the design. Although the introduction of moderator rods can effectively improve the moderation performance of S-CO2 reactor assembly, it will lead to the deterioration of uniform moderation. To further improve the uniform moderation, arrangement of moderator rods and fuel enrichment partition are studied. Finally, the results show clearly that a better balance between uniform moderation and sufficient moderation can be obtained in the high-performance S-CO2 reactor assembly.

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A Multi-Objective-Driven Placement Technique for Digital Microfluidic Biochips

Journal of Circuits System and Computers ◽

10.1142/s0218126619500762 ◽

2019 ◽

Vol 28 (05) ◽

pp. 1950076

Author(s):

Chaowei Wan ◽

Xiaodao Chen ◽

Dongbo Liu

Keyword(s):

Computer Aided Design ◽

High Performance ◽

Low Cost ◽

Operation Time ◽

Physical Design ◽

Multi Objective ◽

Total Operation Time ◽

Microfluidic Biochips ◽

Chip Size ◽

Digital Microfluidic

Microfluidic biochips are extensively utilized in biochemistry procedures due to their low cost, high precision and efficiency when compared to traditional laboratory procedures. Recent, computer-aided design (CAD) techniques enable a high performance in digital microfluidic biochip design. A key part in digital microfluidic biochip CAD design is the biochip placement procedure which determines the physical location for biological reactions during the physical design. For the biochip physical design, multiple objects need to be considered, such as the size of the chip and the total operation time. In this paper, a multi-objective optimization is proposed based on Markov decision processes (MDPs). The proposed method is evaluated on a set of standard biochip benchmarks. Compared to existing works, experimental results show that the total operation time, the capacity for routing and the chip size can be optimized simultaneously.

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Timing Challenges for Very Deep Sub-Micron (VDSM) IC

VLSI Design ◽

10.1080/1065514021000012183 ◽

2002 ◽

Vol 15 (3) ◽

pp. 557-562 ◽

Cited By ~ 3

Author(s):

Ichiang Lin ◽

Chien-In Henry Chen

Keyword(s):

Market Share ◽

High Performance ◽

Logic Synthesis ◽

Physical Design ◽

Timing Verification ◽

Ic Design ◽

Cell Library ◽

Timing Closure ◽

Interconnect Delay ◽

Critical Paths

Many IC design houses failed to be market leaders because they miss the market window due to timing closure problems. Compared to half-micron designs, the amount of time spent on timing verification has greatly increased. Cell delays can be accurately estimated during logic synthesis. However, interconnect delays are unknown until the wire geometry is defined in physical design. Logic synthesis using the cell library models for interconnect delay estimates may be statistically accurate, but can not predict the delay of individual nets accurately. Delay estimates for individual nets (global nets, long wires, large fan-outs, buses), which matter most for the critical paths can be inaccurate and cause a design failure. Inaccurate timing verification causes silicon failure in shipped products that results in the loss of millions of dollars spent designing a high-performance product and potentially larger costs due to lost market share. Full-chip, sign-off verification with silicon-accuracy will allow these problems to be discovered and fixed before tape-out.

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A High Performance Energy Analyzer for Use in Electron Scanning Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061975 ◽

1969 ◽

Vol 27 ◽

pp. 14-15

Author(s):

A. V. Crewe ◽

M. Isaacson ◽

D. Johnson

Keyword(s):

High Performance ◽

Vertical Plane ◽

Median Plane ◽

Electron Gun ◽

Uniform Field ◽

Loss Mechanism ◽

Electron Scanning Microscopy ◽

Sector Type ◽

Double Focusing ◽

Electron Energy Loss

A double focusing magnetic spectrometer has been constructed for use with a field emission electron gun scanning microscope in order to study the electron energy loss mechanism in thin specimens. It is of the uniform field sector type with curved pole pieces. The shape of the pole pieces is determined by requiring that all particles be focused to a point at the image slit (point 1). The resultant shape gives perfect focusing in the median plane (Fig. 1) and first order focusing in the vertical plane (Fig. 2).

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Vacuum System to Minimize the Specimen Contamination of High-Performance EM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077967 ◽

1977 ◽

Vol 35 ◽

pp. 68-69

Author(s):

N. Yoshimura ◽

K. Shirota ◽

T. Etoh

Keyword(s):

Electron Microscope ◽

High Speed ◽

High Performance ◽

High Vacuum ◽

Vacuum System ◽

Pump System ◽

Pumping System ◽

Diffusion Pump ◽

Almost All ◽

Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

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