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Li-Wei Lee Li-Hui Wang Shyi-Ming Chen Yung-Ho Leu 《Fuzzy Systems, IEEE Transactions on》2006,14(3):468-477
In our daily life, people often use forecasting techniques to predict weather, economy, population growth, stock, etc. However, in the real world, an event can be affected by many factors. Therefore, if we consider more factors for prediction, then we can get better forecasting results. In recent years, many researchers used fuzzy time series to handle prediction problems. In this paper, we present a new method to predict temperature and the Taiwan Futures Exchange (TAIFEX), based on the two-factors high-order fuzzy time series. The proposed method constructs two-factors high-order fuzzy logical relationships based on the historical data to increase the forecasting accuracy rate. The proposed method gets a higher forecasting accuracy rate than the existing methods. 相似文献
404.
吕庸厚 《食品与生物技术学报》1984,3(3)
长期以来,在凸轮机构中用压力角α;在连杆机构中用传动角γ(因为丨90°-γ丨=α,实质上仍是压力角)作为衡量机构传动质量的指标和设计依据。本文通过分析,指出了压力角作为这种指标的缺陷和提出了新的机构传动质量指标Ψ'=tga'tgφ',其中α'为实际压力角,φ'为从动件与机架间的当量摩擦角。文章还阐述了新指标在机构分析和综合上的应用。 相似文献
405.
The video streaming quality in a wireless communication network environment is largely affected by various network characteristics, such as a limited channel bandwidth and a variant transmission rate. The playback quality of User Equipments (UEs) may not be smooth when the service is delivered via a wireless environment. From the viewpoints of most video receivers, a smooth playback with a lower video quality may be more significant than a lagged or distorted playback with a higher video quality as the transmission rate degrades. Based on the above, we sketch an adaptation agent—Transmission‐Rate Adapted Streaming Server (TRASS), which is located between the original video server and UEs, to adaptively transform the streaming video based on the real transmission rate. In our proposed scheme, UEs would feedback their network access statuses to TRASS and then TRASS would deliver adaptive quality of video streams to UEs according to their feedbacks. The theoretical analysis and simulations using different video tracks encoded in MPEG‐4 and H.264/AVC formats show that TRASS can help wireless streaming users to get a smooth playback quality with a lower packet failure rate. With a low probability of receiving a worse quality of video, users' Quality of Experience can subsequently be raised. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
406.
This paper carries out a detailed review of previous studies that employed metaheuristics to address problems/issues encountered in the life time of a construction or engineering project. The review is organized around critical problems/issues including engineering, cost estimation, planning, scheduling, and monitoring and control of project operations, with the objectives to optimize cost and time through the efficient uses of constrained or unconstrained resources. Metaheuristics are emphasized because they are especially suitable when approximate solutions are good enough in the case that the global optimum is either unknown or computationally too expensive to obtain it; both are characteristics of a typical large scale project. Based on the review, we offer our view of this research area and their potential for practical use. An attempt is also made to identify project management related topics where further advancement needs to be made. 相似文献
407.
Resveratrol Prevents the Development of Hypertension Programmed by Maternal Plus Post‐Weaning High‐Fructose Consumption through Modulation of Oxidative Stress,Nutrient‐Sensing Signals,and Gut Microbiota
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408.
Ruoyu Chen Adam Bratten Joshua Rittenhouse Ming Leu Haiming Wen 《Journal of the American Ceramic Society》2023,106(7):4028-4037
A novel additive manufacturing approach is herein reported for manufacturing high mechanical strength continuous carbon fiber-reinforced silicon carbide (Cf/SiC) composite materials. Continuous carbon fibers were coated with polycarbosilane (PCS) using a colloidal evaporative deposition process and then coextruded with high solid content SiC ink. The zeta potential of the SiC ink was adjusted to optimize the printing ability of the suspension. During sintering, small SiC grains and whiskers were generated in the gaps in and around the PCS-coated carbon fibers, which led to the improved flexural strength and density of the composites. Meanwhile, the PCS coating on the surface of the carbon fibers prevented the carbon fibers from reacting with SiO gas generated by reactions between the SiC matrix and SiO2 and sintering additives (Al2O3 and Y2O3), effectively preserving the structural integrity of the carbon fibers. Compared to the SiC specimens containing uncoated carbon fibers, the density of the specimens fabricated with coated carbon fibers was increased from 2.51 to 2.85 g/cm3, and the strength was increased from 190 to 232 MPa. 相似文献
409.
Yuan-Wen Hsiao Bi Shane Cheng Hung-Chieh Hsu Shih-Hsiung Wu Hsuan-Ta Wu Ching-Chich Leu Chuan-Feng Shih 《Advanced functional materials》2023,33(21):2300169
This research demonstrates a state-of-the-art vertical-transport photodetector with an n-type 3D MAPbI3/p-type quasi-2D (Q-2D) BA2MA2Pb3I10 perovskite heterojunction. This structure introduces a ≈0.6 V built-in electric field at the n-p junction that greatly improves the characteristics of the perovskite photodetector, and the presence of Q-2D perovskite on the surface improves the life. The electrical polarities of the 3D and the Q-2D perovskite layers are simply controlled by self-constituent doping, making clearly defined n-p characteristics. Doctor-blade coating is used to fabricate the photodetector with a large area. The Q-2D materials with highly oriented (040) Q-2D (n = 2,3) planes are near the surface, and the (111) preferred planes mixed with high index Q-2D materials (n = 4,5) are found near the 3D/Q-2D interface. The stacking and interface are beneficial for carrier extraction and transport, yielding an external quantum efficiency of 77.9%, a carrier lifetime long as 295.7 ns, and a responsibility of 0.41 A W−1. A low dark current density of 6.2 × 10−7 mA cm−2 and a high detectivity of 2.82 × 1013 Jones are obtained. Rise time and fall time are fast as 1.33 and 10.1 µs, respectively. The results show the application potential of 3D/Q-2D n-p junction perovskite photodetectors. 相似文献