http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Qingbo Tian,Daquan Sun,Zeyu Gu,Zhijie Lv 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.3
The effects of Na2O content, water to binder (W/B) ratio, and the modulus (Ms) of alkaline activator solution on a fly ash-basedgeopolymer paste (FGP) were investigated. The microstructure of the pastes was observed and characterised by Scanningelectron microscope and X-ray diffraction. The results showed that the increase of Na2O content and Ms resulted in an increasein compressive strength: an increase in the W/B ratios led to a decreased compressive strength. It was found that the highcompressive strength was achieved as Ms of the alkaline activator was 1.5, and the content of this activator was 8.0-12.0% bythe proportion of Na2O to fly ash. The compressive strength of these pastes was between 26.5-39.6 MPa at 28 days when theywere cured at 85 ºC for 1 h followed by curing under standard conditions. OH− concentration, determined by Na2O content,Ms, and water content, seemed to be a crucial parameter influencing the compressive strength. There was an optimal OH−concentration range, in which the appropriate strength of geopolymer paste would be achieved. An increased alkaline contentpromoted the reaction between the mineral phases of the fly ash with the alkaline activator and the formation of an additionalsodium aluminosilicate hydrate (N-A-S-H) gel.
( Yi Xie ),( Weidong Xiao ),( Daquan Tang ),( Jiuyang Tang ),( Guoming Tang ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.5
Energy efficiency is one of the most critical issues in the design of wireless sensor networks. In object-tracking sensor networks, the data storage and query processing should be energy-conserving by decreasing the message complexity. In this paper, a Prediction-based Energy-conserving Approximate StoragE schema (P-EASE) is proposed, which can reduce the query error of EASE by changing its approximate area and adopting predicting model without increasing the cost. In addition, focusing on reducing the unnecessary querying messages, P-EASE enables an optimal query algorithm to taking into consideration to query the proper storage node, i.e., the nearer storage node of the centric storage node and local storage node. The theoretical analysis illuminates the correctness and efficiency of the P-EASE. Simulation experiments are conducted under semi-random walk and random waypoint mobility. Compared to EASE, P-EASE performs better at the query error, message complexity, total energy consumption and hotspot energy consumption. Results have shown that P-EASE is more energy-conserving and has higher location precision than EASE.
( Yi Xie ),( Guoming Tang ),( Daifei Wang ),( Weidong Xiao ),( Daquan Tang ),( Jiuyang Tang ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.6
Uncertainty is ubiquitous in target tracking wireless sensor networks due to environmental noise, randomness of target mobility and other factors. Sensing results are always unreliable. This paper considers unreliability as it occurs in wireless sensor networks and its impact on target-tracking accuracy. Firstly, we map intersection pairwise sensors` uncertain boundaries, which divides the monitor area into faces. Each face has a unique signature vector. For each target localization, a sampling vector is built after multiple grouping samplings determine whether the RSS (Received Signal Strength) for a pairwise nodes` is ordinal or flipped. A Fault-Tolerant Target-Tracking (FTTT) strategy is proposed, which transforms the tracking problem into a vector matching process that increases the tracking flexibility and accuracy while reducing the influence of in-the-filed factors. In addition, a heuristic matching algorithm is introduced to reduce the computational complexity. The fault tolerance of FTTT is also discussed. An extension of FTTT is then proposed by quantifying the pairwise uncertainty to further enhance robustness. Results show FTTT is more flexible, more robust and more accurate than parallel approaches.