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91.
This paper studies the partial consensus problem for identical feedforward dynamic systems with input saturations. We construct two consensus protocols using the partial‐state information and full‐state information, respectively. Applying a change of coordinates, feedforward system is transformed into the block diagonal form. Then, by utilizing the bounded real lemma and small gain theorem, we solve the partial consensus problem, and the existence of each protocol is derived. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
92.
Distributed
filtering and synchronization of diffusively state‐coupled heterogeneous systems 下载免费PDF全文
This paper studies distributed filtering‐based ssynchronization of diffusively state‐coupled heterogeneous systems. For given heterogeneous subsystems and a network topology, sufficient conditions for the filtering‐based synchronization are developed with a guaranteed performance. The estimation and synchronization error dynamics are obtained in a decoupled form, and it is shown that the filter and the controller can be designed separately by LMIs. The feasibility of the proposed design method using LMIs is discussed, and the main results are validated through examples with various setup. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
93.
Reductive debromination of polybrominated diphenyl ethers in anaerobic sediment and a biomimetic system 总被引:8,自引:0,他引:8
Because of the bioaccumulation of penta- and tetrapolybrominated diphenyl ether (PBDE) flame retardants in biota,the environmental biotransformation of decabromodiphenyl ether (BDE-209) is of interest. BDE-209 accounts for more than 80% by mass of PBDE production and is the dominant PBDE in sediments. Most sediments are anaerobic and reports of microbial reductive dehalogenation of hydrophobic persistent organohalogen pollutants are numerous. Reductive debromination of BDE-209 in the environment could provide a significant source of lesser-brominated PBDEs to biota. Moreover, a recent study showed that BDE-209 debrominates in sewage sludge, and another demonstrated that some halorespiring bacteria will debrominate BDE-209. To determine whether reductive debromination of BDE-209 occurs in sediments, parallel experiments were conducted using anaerobic sediment microcosms and a cosolvent-enhanced biomimetic system. In the biomimetic system, reductive debromination occurred at rates corresponding to bromine substitution levels with a BDE-209 half-life of only 18 s compared with a halflife of almost 60 days for 2,2',4,4'-tetrabromodiphenyl ether. In sediment, the measured debromination half-life of BDE-209 was well over a decade and was in good agreement with the predicted value obtained from the biomimetic experiment. Product congeners were predominantly double para-substituted. BDE-209 debrominated in sediment with a corresponding increase in nona-, octa-, hepta-, and hexa-PBDEs. Nine new PBDE congeners appeared in sediment from reductive debromination. Given the very large BDE-209 burden already in sediments globally, it is important to determine whether this transformation is a significant source of lesser-brominated PBDEs to the environment. 相似文献
94.
A rate-distortion (R-D) optimized progressive coding algorithm for three-dimensional (3D) meshes is proposed in this work. We propose the prioritized gate selection and the curvature prediction to improve the connectivity and geometry compression performance, respectively. Furthermore, based on the bit plane coding, we develop a progressive transmission method, which improves the qualities of intermediate meshes as well as that of the fully reconstructed mesh, and extend it to the view-dependent transmission method. Experiments on various 3D mesh models show that the proposed algorithm provides significantly better compression performance than the conventional algorithms, while supporting progressive reconstruction efficiently. 相似文献
95.
Previous studies on mobile Web browsers have focused on phone features and technical performance, but not on the user interface. In this study, we compared three mobile Web browsers in the iPhone and ultimately proposed recommendations for the design of mobile Web browsers for smartphones. To develop such recommendations, we redefined the user interface (UI) components of mobile Web browsers from previous studies to conform to smartphones and compared the Chrome, Safari, and Opera Mini-browsers. To do this, we conducted experiments on usability tests with several dependent variables, including usefulness, perceived time reduction, minimal action, usability, ease to memorize, learnability, fun, and satisfaction. Finally, we developed several recommendations, based on the experimental results and participant interviews, which will fulfill user needs for the interface design of mobile Web browsers for smartphones. Multi-windows need to be implemented in a 3D environment. Developers should consider UI components and features that ease learning how to use the browser for novice users. 相似文献
96.
Hyuk-Jin Kang Hyung-Jung KimJi-Seok Kim Woon-Yong ChoiWon-Shik Chu Sung-Hoon Ahn 《Robotics and Computer》2010
A light guide panel (LGP) is an element of the liquid crystal display (LCD) back light unit (BLU), which is used for display devices. In this study, the laser marking process is applied to the fabrication of light guide panels as the new fabrication process. In order to obtain a light guide panel which has high luminance and uniformity, four principal parameters such as power, scanning speed, ratio of line gap, and number of line were selected. A web-based design tool was developed to generate patterns of light guide panel via the network, and the tool may assist the designer to develop various prototype patterns. Topcon-BM7 was used for luminance measurement of each specimen with 100 mm×100 mm area. By Taguchi method, optimized levels of each parameter were found, and luminance of 3523 cd/cm2 and uniformity of 92% were achieved using the laser machined BLU. 相似文献
97.
Impact of a simple load balancing approach and an incentive-based scheme on MANET performance 总被引:1,自引:0,他引:1
Most reactive mobile ad hoc network (MANET) routing protocols such as AODV and DSR do not perform search for new routes until the network topology changes. But, low node mobility does not affect the MANET connectivity and the same routes may be used for a long time. This may cause concentration of traffic on few mobile stations (MSs), which results in congestion and hence longer end-to-end delay. In addition, continuous use of MSs may cause their battery power to get exhausted rapidly. Expiration of MS energy causes disruption of connections traversing through the MSs and could generate many simultaneous new routing requests. Therefore, we propose a load balancing approach called Simple Load Balancing Approach (SLBA), which can be transparently added to any current reactive routing protocol such as AODV and DSR. SLBA minimizes the traffic concentration by allowing each MS to drop RREQ or to give up packet forwarding depending on its own traffic load. Meanwhile, MSs may deliberately give up forwarding packets to save their own energy. For encouraging MSs to volunteer in forwarding packets, we introduce a reward scheme for packet forwarding, named Protocol-Independent Fairness Algorithm (PIFA). We compare the performance of AODV and DSR with and without SLBA and PIFA. Simulation results indicate that SLBA can distribute traffic very well and improve the MANET performance. PIFA is also observed to prevent MANET partitioning and any performance degradation due to selfish nodes. 相似文献
98.
Kangmin Kim Jin-Sook Kwon Changhwan Ahn Eui-Bae Jeung 《International journal of molecular sciences》2022,23(3)
There is growing concern regarding the health and safety issues of endocrine-disrupting chemicals (EDCs). Long-term exposure to EDCs has serious adverse health effects through both hormone-direct and hormone-indirect ways. Accordingly, some EDCs can be a pathogen and an inducer to the susceptibility of disease, even if they have a very low affinity on the estrogen receptor, or no estrogenic effect. Endoplasmic reticulum (ER) stress recently attracted attention in this research area. Because ER and ER stress could be key regulators of the EDC’s adverse effects, such as the malfunction of the organ, as well as the death, apoptosis, and proliferation of a cell. In this review, we focused on finding evidence which shows that EDCs could be a trigger for ER stress and provide specific examples of EDCs, which are known to cause ER stress currently. 相似文献
99.
Durai Mani Kumaravel Sakthivel Mukannan Arivanandhan Krishnakumar Balu Thiripuranthagan Sivakumar Ahn Young-Ho 《Journal of Porous Materials》2021,28(6):1907-1917
Journal of Porous Materials - Valeric acid can be produced by selective hydrogenation of biomass-derived levulinic acid. The present work aims to synthesize ethyl valerate (EV), a fuel, fuel... 相似文献
100.
Zinc sulfide [ZnS] thin films were deposited on glass substrates using radio frequency magnetron sputtering. The substrate
temperature was varied in the range of 100°C to 400°C. The structural and optical properties of ZnS thin films were characterized
with X-ray diffraction [XRD], field emission scanning electron microscopy [FESEM], energy dispersive analysis of X-rays and
UV-visible transmission spectra. The XRD analyses indicate that ZnS films have zinc blende structures with (111) preferential
orientation, whereas the diffraction patterns sharpen with the increase in substrate temperatures. The FESEM data also reveal
that the films have nano-size grains with a grain size of approximately 69 nm. The films grown at 350°C exhibit a relatively
high transmittance of 80% in the visible region, with an energy band gap of 3.79 eV. These results show that ZnS films are
suitable for use as the buffer layer of the Cu(In, Ga)Se2 solar cells. 相似文献