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排序方式: 共有704条查询结果,搜索用时 15 毫秒
1.
Information Systems and e-Business Management - Collaborative filtering (CF) is a popular and widely accepted recommendation technique. CF is an automated form of word-of-mouth communication... 相似文献
2.
This paper presents the computational study of fluid/structure interaction (FSI) analysis in the molding process using the Mesh-based parallel Code Coupling Interface (MpCCI) method with finite volume coding (FLUENT 6.3) and finite element coding (ABAQUS 6.9). The FSI analysis is implemented on the molded package during the encapsulation process with different inlet pressures. Real-time flow visualization, deformation and stress of the silicon die during the encapsulation process are presented in this paper. A fluctuation phenomenon of the silicon die is found in the encapsulation process when the inlet pressure increases. The maximum deformation during the process is determined at different locations on the silicon die, calculated during the final stage of the filling process. The deformation and stress of the die is exponentially increased with increasing inlet pressure. The maximum stress on the solder bump is concentrated near to the inlet gate. Thus, the present FSI analysis approach is expected to be a guideline or reference and provides better understanding of the encapsulation process for package design in the microelectronic industry. 相似文献
3.
Achim Streit Piotr Bala Alexander Beck-Ratzka Krzysztof Benedyczak Sandra Bergmann Rebecca Breu Jason Milad Daivandy Bastian Demuth Anastasia Eifer André Giesler Björn Hagemeier Sonja Holl Valentina Huber Nadine Lamla Daniel Mallmann Ahmed Shiraz Memon Mohammad Shahbaz Memon Michael Rambadt Morris Riedel Mathilde Romberg Bernd Schuller Tobias Schlauch Andreas Schreiber Thomas Soddemann Wolfgang Ziegler 《电信纪事》2010,65(11-12):757-762
UNICORE is a European Grid Technology with more than 10 years of history. Originating from the Supercomputing domain, the latest version UNICORE 6 has turned into a general-purpose Grid technology that follows established standards and offers a rich set of features to its users. The paper starts with an architectural insight into UNICORE 6, highlighting the workflow features, standards and the different clients. Next, the current state of advancement is presented by describing recent developments. The paper closes with an outlook on future planned developments. 相似文献
4.
Carl R. Nassar Bala Natarajan David Wiegandt Zhiqiang Wu 《Wireless Communications and Mobile Computing》2002,2(4):381-403
Multi‐carrier technologies in general, and OFDM and MC‐CDMA in particular, are an integral part of the wireless landscape. In this second part of a two‐part survey, the authors present an innovative set of spreading codes known as CI codes, and demonstrate how these significantly increase performance and capacity in OFDM and MC‐CDMA systems, all the while eliminating PAPR concerns. Regarding OFDM: the spreading of each symbol over all N carriers using CI spreading codes (replacing the current one symbol per carrier strategy) are presented. CI codes are ideally suited for spreading OFDM since, when compared to traditional OFDM, CI‐based OFDM systems achieve the performance of coded OFDM (COFDM) while maintaining the throughput of uncoded OFDM, and, at the same time, eliminate PAPR concerns. When applied to MC‐CDMA, CI codes provide a simple means of supporting 2N users on N carriers while maintaining the performance of an N‐user Hadamard Walsh code MC‐CDMA system, i.e., CI codes double MC‐CDMA network capacity without loss in performance. The CI codes used in OFDM and MC‐CDMA systems are directly related to the CI pulse (chip) shapes used to enhance TDMA and DS‐CDMA (see part 1): hence, the CI approach provides a common hardware platform for today's multi‐carrier/multiple‐access technologies, enabling software radio applications. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
5.
Slip energy recovery induction motor drives are used in high power applications, in which by controlling the slip power a variable speed drive system is provided. However, poor power factor is a disadvantage of the system. Presence of sub-harmonics of the line frequency on the stator side is one of the special features of these drives. A phase-controlled inverter can absorb the reactive power from the supply and inject the low-order current harmonics with relatively high amplitudes to the supply. This paper simulates the harmonic content of waveforms in various points of drive at different speeds, based on the hybrid model (dqabc). Then the sinusoidal pulse-width-modulation (SPWM) control technique is used in order to improve the power factor of the drive and to weaken the injected low-order harmonics to the supply. Based on the frequency spectrum, total harmonic distortion, distortion factor and power factor, two phase control and SPWM techniques are compared and the advantage of the SPWM technique over the phase control technique is shown 相似文献
6.
This paper presents the simulation of pressurized underfill encapsulation process for high I/O flip chip package. 3D model of flip chip packages is built using GAMBIT and simulated using FLUENT software. Injection methods such as central point, one line, L-type and U-type are studied. Cross-viscosity model and volume of fluid (VOF) technique are applied for melt front tracking of the encapsulant. The melt front profiles and pressure field for all injection types are analyzed and presented. The pressure distribution within the flip-chip, fill volume versus filling time and viscosity versus shear rate are also plotted. The U-type injection is found to be faster in filling. The numerical results are compared with the previous experimental results and found in good conformity. The strength of CFD software in handling underfill encapsulation problems is proved to be excellent. 相似文献
7.
Predictive Validity of an Empirical Approach for Selecting Promising Message Topics: A Randomized‐Controlled Study 下载免费PDF全文
Stella Juhyun Lee Emily Brennan Laura Anne Gibson Andy S. L. Tan Ani Kybert‐Momjian Jiaying Liu Robert Hornik 《The Journal of communication》2016,66(3):433-453
Several message topic selection approaches propose that messages based on beliefs pretested and found to be more strongly associated with intentions will be more effective in changing population intentions and behaviors when used in a campaign. This study aimed to validate the underlying causal assumption of these approaches which rely on cross‐sectional belief–intention associations. We experimentally tested whether messages addressing promising themes as identified by the above criterion were more persuasive than messages addressing less promising themes. Contrary to expectations, all messages increased intentions. Interestingly, mediation analyses showed that while messages deemed promising affected intentions through changes in targeted promising beliefs, messages deemed less promising also achieved persuasion by influencing nontargeted promising beliefs. Implications for message topic selection are discussed. 相似文献
8.
9.
Owens C Zisser H Jovanovic L Srinivasan B Bonvin D Doyle FJ 《IEEE transactions on bio-medical engineering》2006,53(6):996-1005
Run-to-run control has been applied to several traditional batch processes in the chemical industry. The 24-h cycle of eating meals, measuring blood glucose concentrations, and delivering the correct insulin bolus, with the goal of achieving the optimal blood glucose profile, can be viewed in the same spirit as traditional batch processes such as emulsion polymerization. In this paper, we aim to exploit the "repetitive" nature of the insulin therapy of people with Type 1 diabetes. A run-to-run algorithm is used on a virtual diabetic patient model to control blood glucose concentrations. The insulin input is parameterized into the timing and amount of the dose while the glucose output is parameterized into the maximum and minimum glucose concentrations. Robustness of the algorithm to variations in the meal amount, meal timing, and insulin sensitivity parameter is addressed. In general, the algorithm is able to converge when the meal timing is varied within +/- 40 min. If the meal size is underestimated by approximately 10 grams (g), the algorithm is able to converge within a reasonable time frame for breakfast, lunch, and dinner. If the meal size is overestimated by 20-25 g, the algorithm is able to converge. When random variations in the meal timing and the meal amount are introduced, the variation on the output variables, Gmax and Gmin, scales according to the amount of variation allowed. Along with this, the insulin sensitivity of the virtual patient model is varied. The algorithm is robust for differences in insulin sensitivity less than +/- 50% of the nominal value. 相似文献
10.
Filip Aniés Mohamad I. Nugraha Arona Fall Julianna Panidi Yuxi Zhao Patrice Vanelle Leonidas Tsetseris Julie Broggi Thomas D. Anthopoulos Martin Heeney 《Advanced functional materials》2023,33(12):2212305
Molecular doping is a powerful and increasingly popular approach toward enhancing electronic properties of organic semiconductors (OSCs) past their intrinsic limits. The development of n-type dopants has been hampered, however, by their poor stability and high air-reactivity, a consequence of their generally electron rich nature. Here, the use of air-stable carboxylated dopant precursors is reported to overcome this challenge. Active dopants are readily generated in solution by thermal decarboxylation and applied in n-type organic field-effect transistors (OFETs). Both 1,3-dimethylimidazolium-2-carboxylate (CO2-DMI) and novel dopant 1,3-dimethylbenzimidazolium-2-carboxylate (CO2-DMBI) are applied to n-type OFETs employing well-known organic semiconductors (OSCs) P(NDI2OD-T2), PCBM, and O-IDTBR. Successful improvement of performance in all devices demonstrates the versatility of the dopants across a variety of OSCs. Experimental and computational studies indicate that electron transfer from the dopant to the host OSC is preceded by decarboxylation of the precursor, followed by dimerization to form the active dopant species. Transistor studies highlight CO2-DMBI as the most effective dopant, improving electron mobility by up to one order of magnitude, while CO2-DMI holds the advantage of commercial availability. 相似文献