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排序方式: 共有813条查询结果,搜索用时 15 毫秒
11.
12.
Seng F. Chung 《加拿大化工杂志》1972,50(5):657-662
A mathematical model of a through-circulation dryer is proposed. This model approximates the drying time of constantrate drying and fallingrate drying processes. Based on the proposed model, the optimal drying conditions of maximizing the drying production rate in a continuous through-circulation dryer are obtained. The drying production rate, in terms of the independent operating variables, is a nonlinear objective function, and is optimized under the nonlinear inequality constraint functions by a differential algorithm. 相似文献
13.
Surface reconstruction means that retrieve the data by scanning an object using a device such as laser scanner and construct it using the computer to gain back the soft copy of data on that particular object. It is a reverse process and is very useful especially when that particular object original data is missing without doing any backup. Hence, by doing so, the data can be recollected and can be stored for future purposes. The type of data can be in the form of structure or unstructured points. The accuracy of the reconstructed result should be concerned because if the result is incorrect, hence it will not exactly same like the original shape of the object. Therefore, suitable methods should be chosen based on the data used. Soft computing methods also have been used in the reconstruction field. This papers highlights the previous researches and methods that has been used in the surface reconstruction field. 相似文献
14.
Khaksar Pour Amin Chaw Seng Woo Palaiahnakote Shivakumara Tahaei Hamid Anuar Nor Badrul 《Multimedia Tools and Applications》2021,80(16):24121-24145
Multimedia Tools and Applications - Rating a video based on its content is one of the most important solutions to classify videos for audience age groups. In this regard, Film content rating and TV... 相似文献
15.
Shi Xiaoying Lv Fanshun Seng Dewen Zhang Jiaming Chen Jing Xing Baixi 《Multimedia Tools and Applications》2021,80(6):8355-8375
Multimedia Tools and Applications - The graph convolutional network (GCN), which can handle graph-structured data, is enjoying great interest in recent years. However, while GCN achieved remarkable... 相似文献
16.
JD Kasprzak WB Vletter JR Roelandt JR van Meegen R Johnson FJ Ten Cate 《Canadian Metallurgical Quarterly》1998,40(2):314-321
To investigate possible biochemical mechanisms underlying the "toxic gain of function" associated with polyglutamine expansions, the ability of guinea pig liver tissue transglutaminase to catalyze covalent attachments of various polyamines to polyglutamine peptides was examined. Of the polyamines tested, spermine is the most active substrate, followed by spermidine and putrescine. Formation of covalent cross links between polyglutamine peptides and polyamines yields high-M(r) aggregates--a process that is favored with longer polyglutamines. In the presence of tissue transglutaminase, purified glyceraldehyde-3-phosphate dehydrogenase (a key glycolytic enzyme that binds tightly to the polyglutamine domains of both huntingtin and dentatorubral-pallidoluysian atrophy proteins) is covalently attached to polyglutamine peptides in vitro, resulting in the formation of high-M(r) aggregates. In addition, endogenous glyceraldehyde-3-phosphate dehydrogenase of a Balb-c 3T3 fibroblast cell line overexpressing human tissue transglutaminase forms cross-links with a Q60 polypeptide added to the cell homogenate. Possibly, expansion of polyglutamine domains (thus far known to occur in the gene products associated with at least seven neurodegenerative diseases) leads to increased/aberrant tissue transglutaminase-catalyzed cross-linking reactions with both polyamines and susceptible proteins, such as glyceraldehyde-3-phosphate dehydrogenase. Formation of cross-linked heteropolymers may lead to deposition of high-M(r) protein aggregates, thereby contributing to cell death. 相似文献
17.
R. Wiegerink H. Ten Pierick C. Jaspers W. De Haan D. De Greef 《Analog Integrated Circuits and Signal Processing》1996,9(2):189-195
In this paper a variable-gamma system is discussed for application in high-quality colour television receivers. A variable-gamma system can significantly improve the quality of the video image by enhancing the contrast in darker parts of the image without degrading the lighter areas of the screen. The adjustment of gamma can replace the traditional contrast and intensity adjustments.The main part of the variable-gamma system is a nonlinear function block, which is implemented by an MOS translinear (MTL) circuit. This circuit was realized in a standard 2.5 m CMOS process. The circuit operates at a single 5V supply voltage. The measured small-signal-3dB bandwidth is 20MHz. The circuit response is insensitive to temperature, which is an important property of translinear circuits. 相似文献
18.
Dissipative particle dynamics simulations for fibre suspensions in newtonian and viscoelastic fluids
Duc Duong-Hong Nhan Phan-Thien Khoon Seng Yeo Gilles Ausias 《Computer Methods in Applied Mechanics and Engineering》2010,199(23-24):1593-1602
A versatile model of fibre suspensions in Newtonian and viscoelastic fluids has been developed using dissipative particle dynamics method. The viscoelastic fluid is modelled by linear chains with linear connector spring force (the Oldroyd-B model), which is known to be a reasonable model for the so-called Boger fluid (a dilute suspension of polymer in a highly viscous solvent). The numerical results are in excellent agreement with the analytical results of the Oldroyd-B model in simple shear flow. An effective meso-scale model of fibre in DPD is proposed and then incorporated with simple Newtonian fluid and our Boger fluid to enable entirely study rheological properties of fibre suspensions in both Newtonian and viscoelastic solvents. The numerical results are well compared with available experimental data and other numerical models. 相似文献
19.
An Efficient Path Planning and Control Algorithm for RUAV’s in Unknown and Cluttered Environments 总被引:1,自引:0,他引:1
Kwangjin Yang Seng Keat Gan Salah Sukkarieh 《Journal of Intelligent and Robotic Systems》2010,57(1-4):101-122
This paper presents an efficient planning and execution algorithm for the navigation of an autonomous rotary wing UAV (RUAV) manoeuvering in an unknown and cluttered environment. A Rapidly-exploring Random Tree (RRT) variant is used for the generation of a collision free path and linear Model Predictive Control(MPC) is applied to follow this path. The guidance errors are mapped to the states of the linear MPC structure by using the nonlinear kinematic equations. The proposed path planning algorithm considers the run time of the planning stage explicitly and generates a continuous curvature path whenever replanning occurs. Simulation results show that the RUAV with the proposed methodology successfully achieves autonomous navigation regardless of its lack of prior information about the environment. 相似文献
20.
This article proposes an asymmetric topology for transmit/receive (T/R) switches and more importantly presents a comparative study of both LC‐tuned and resistive body‐floating techniques for improving the power‐handling capability of the T/R switches in the same 0.18‐μm triple‐well CMOS. It is shown from simulations and measurements that the switches adopting either technique achieve comparable performances. For instance, the switch employing the LC‐tuned body‐floating technique exhibits insertion loss of 1.5 dB, isolation of 23.5 dB, and power‐handling capability of 22.5 dBm at 5.2 GHz, whereas the switch using the resistive body‐floating technique exhibits insertion loss of 1.3 dB, isolation of 24 dB, and power‐handling capability of 22.2 dBm, respectively. Therefore, one can conclude that the asymmetric topology with the resistive body‐floating technique is more suitable for designing T/R switches for wireless local area network applications as it consumes smaller silicon area. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献