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排序方式: 共有277条查询结果,搜索用时 15 毫秒
1.
In this paper, mobility parameters for enhancement-mode N-channel 4H SiC MOSFETs are extracted and implemented into 2-D device simulation program and SPICE circuit simulator. The experimental data were obtained from lateral N-channel 4H SiC MOSFETs with nitrided oxide–semiconductor interfaces, exhibiting normal mobility behavior. The presence of increasing interface-trap density (Dit) toward the edge of the conduction band is included during the 2-D device simulation. Using measured distribution of interface-trap density for simulation of the transfer characteristics leads to a good agreement with the experimental transfer characteristic. 相似文献
2.
The stress buffer layer (SBL) is a widely applied improvement in many advanced packages used to release the stress concentration at solder joints. However, it has been generally found that the metal line adjacent to the SBL may suffer larger deformation and its reliability should be addressed. In this study, the panel level package (PLP) technology with solder on polymer (SOP) structure is selected as the testing sample to investigate the effect of SBL. The ball shear strength test is conducted first to investigate the reliability of metal trace in PLP. In addition, finite element (FE) analysis is applied to understand the actual thermo-mechanical behavior of PLP after its assembly. The package-level and board-level reliability assessments are compared, and the suggested layout of the redistribution layer on the SBL is provided herein. 相似文献
3.
Automatic visual inspection has become one of the active research issues in machine vision technology in the past decades. Most of the methodologies developed address the problems of defect detection on a nontextured or regularly textured surface. However, problems in detecting defects on a randomly textured surface, especially cracks, have not received much attention. In this paper, we present a novel algorithm that uses a Wigner model to identify cracks in complex textural backgrounds, regardless of whether the inspected surface is randomly or regularly textured. We also investigate the windowing characteristics of the Wigner distribution and their impact on crack detection. Some of the Brodatz' natural texture images have been used for evaluating the performance of the algorithm. Promising results are obtained and presented in this paper. 相似文献
4.
Ding-Kai Chen Pen-Chung Yew 《Parallel and Distributed Systems, IEEE Transactions on》1996,7(5):463-476
It is extremely difficult to parallelize DOACROSS loops with nonuniform loop-carried dependences. In this paper, we present a static scheduling scheme with an accompanying synchronization strategy that can execute such DOACROSS loops effectively and efficiently. Our approach uses one of the parallelization techniques called Dependence Uniformization, which finds a small set of uniform dependence vectors to cover all possible nonuniform dependences in a DOACROSS loop. It differs from the previous schemes in that we demonstrate a better way to select the uniform dependence vectors. When used with the Static Strip Scheduling scheme, the proposed uniform dependence vector set allows us to enforce dependences with more locality, which reduces the requirement of explicit synchronization considerably while retaining most of the parallelism. This paper describes the uniform dependence vectors selection strategy and the static strip scheduling scheme. The performance analysis and examples are also presented 相似文献
5.
Kin Kit Fong Inn Shi Tan Henry Chee Yew Foo Man Kee Lam Adrian Chiong Yuh Tiong Steven Lim 《中国化学工程学报》2021,33(5):297-305
The rising production of produced water from oilfields had been proven to bring detrimental environmental effects. In this study, an efficient, recyclable, and environmental-friendly reduced graphene oxide immobilized κ-Carrageenan hydrogel composite(κCa GO) was fabricated as an alternative sorbent for crude oil-in-water demulsification. Polyethyleneimine(PEI) was employed to form a stable hydrogel composite. The conditions for the immobilization of graphene oxide(GO) on PEI-modified κ-Carrageenan(κC) beads were optimized appropriately. An immobilization yield of 77% was attained at 2% PEI, 2 h immobilization activation time, and p H6.5. Moreover, the synthesized κCa GO is capable of demulsification with an average demulsification efficiency of 70%. It was found that the demulsification efficiency increases with salinity and κCa GO dosage, and it deteriorates under alkaline condition. These phenomena can be attributed to the interfacial interactions between κCa GO and the emulsion. Furthermore, the κCa GO can be recycled to use for up to six cycles without significant leaching and degradation. As such, the synthesized κCa GO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water. 相似文献
6.
Tan S Chan WM Wai MS Hui LK Hui VW James AE Yeung LY Yew DT 《Microscopy research and technique》2011,74(12):1192-1198
Different doses of ketamine (10 mg/kg, 20 mg/kg, 30 mg/kg, 40 mg/kg, 50 mg/kg, and 60 mg/kg) were injected i.p. (I.P.), respectively, to male ICR mice to determine the optimal dosage for chronic administration. At and above 40 mg/kg I.P. injection, mice had almost no hindlimb movement during swimming test. Subsequently, 30 mg/kg was used as the dose for the study in the toxicity of long-term ketamine administration on urinary bladder and sperm motility. The treatment group were subdivided into two (n = 10 each group); one received daily ketamine treatment i.p. for 3 months and another group for 6 months. Corresponding number of mice in control groups (n = 5 each group) received saline injection instead of ketamine. Terminal dUTP nick and labeling (TUNEL) study and Sirius red staining were carried out on the sectioned slides of the urinary bladders to study the degree of apoptosis in both epithelium and muscular layers of the urinary bladder and the relative thickness of the muscular layers in this organ was also computed. Apoptosis in the bladder epithelium was observed initially in the 3-month ketamine treated mice and the number of apoptotic cells was significantly different (P < 0.05) between the 3-month and 6-month ketamine treated mice and the control. The relative thickness of muscular layers in the bladder wall also decreased significantly (P < 0.05) when the 6-month treated mice and the control were compared. Sirius red staining revealed increase of collagen in the urinary bladder of the treated mice, most evidently 6 months after ketamine treatment. In addition, the sperm motility was studied and there was a statistically significant difference between the control and ketamine treated groups in the percentages of sperms which were motile (P < 0.05). This suggested that the chronic administration of ketamine affected the genital system as well. 相似文献
7.
Quantitative Proteomics Study Reveals Changes in the Molecular Landscape of Human Embryonic Stem Cells with Impaired Stem Cell Differentiation upon Exposure to Titanium Dioxide Nanoparticles 下载免费PDF全文
Lei Pan Yew Mun Lee Teck Kwang Lim Qingsong Lin Xiuqin Xu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(23)
The increasing number of nanoparticles (NPs) being used in various industries has led to growing concerns of potential hazards that NP exposure can incur on human health. However, its global effects on humans and the underlying mechanisms are not systemically studied. Human embryonic stem cells (hESCs), with the ability to differentiate to any cell types, provide a unique system to assess cellular, developmental, and functional toxicity in vitro within a single system highly relevant to human physiology. Here, the quantitative proteomics approach is adopted to evaluate the molecular consequences of titanium dioxide NPs (TiO2 NPs) exposure in hESCs. The study identifies ≈328 unique proteins significantly affected by TiO2 NPs exposure. Proteomics analysis highlights that TiO2 NPs can induce DNA damage, elevated oxidative stress, apoptotic responses, and cellular differentiation. Furthermore, in vivo analysis demonstrates remarkable reduction in the ability of hESCs in teratoma formation after TiO2 NPs exposure, suggesting impaired pluripotency. Subsequently, it is found that TiO2 NPs can disrupt hESC mesoderm differentiation into cardiomyocytes. The study unveils comprehensive changes in the molecular landscape of hESCs by TiO2 NPs and identifies the impact which TiO2 NPs can have on the pluripotency and differentiation properties of human stem cells. 相似文献
8.
Kok Yew Ng Chee Pin Tan Rini Akmeliawati Christopher Edwards 《Asian journal of control》2010,12(5):656-660
This paper investigates and presents conditions that guarantee disturbance decoupled fault reconstruction using sliding mode observers, which are less stringent than those of previous work, and show that disturbance reconstruction is not necessary. An aircraft model validates the ideas proposed in this paper. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
9.
Lum Angeline Su Lyn Chiew Thiam Kian Ng Chirk Jenn Lee Yew Kong Lee Ping Yein Teo Chin Hai 《Universal Access in the Information Society》2017,16(3):775-791
Universal Access in the Information Society - In recent years, researchers have attempted to shift patient decision aids (PDAs) from paper-based to web-based to increase its accessibility. Insulin... 相似文献
10.
This paper presents a disturbance decoupled fault reconstruction (DDFR) scheme using cascaded sliding mode observers (SMOs). The processed signals from a SMO are found to be the output of a fictitious system which treats the faults and disturbances as inputs; the ‘outputs’ are then fed into the next SMO. This process is repeated until the attainment of a fictitious system which satisfies the conditions that guarantee DDFR. It is found that this scheme is less restrictive and enables DDFR for a wider class of systems compared to previous work when only one or two SMOs were used. This paper also presents a systematic routine to check for the feasibility of the scheme and to calculate the required number of SMOs from the outset and also to design the DDFR scheme. A design example verifies its effectiveness. 相似文献