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81.
Thin Nguyen Dinh Phung Brett Adams Svetha Venkatesh 《Knowledge and Information Systems》2014,39(3):667-702
We present a large-scale mood analysis in social media texts. We organise the paper in three parts: (1) addressing the problem of feature selection and classification of mood in blogosphere, (2) we extract global mood patterns at different level of aggregation from a large-scale data set of approximately 18 millions documents (3) and finally, we extract mood trajectory for an egocentric user and study how it can be used to detect subtle emotion signals in a user-centric manner, supporting discovery of hyper-groups of communities based on sentiment information. For mood classification, two feature sets proposed in psychology are used, showing that these features are efficient, do not require a training phase and yield classification results comparable to state of the art, supervised feature selection schemes; on mood patterns, empirical results for mood organisation in the blogosphere are provided, analogous to the structure of human emotion proposed independently in the psychology literature; and on community structure discovery, sentiment-based approach can yield useful insights into community formation. 相似文献
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Dinh Cong Huong Van Thanh Huynh Hieu Trinh 《International Journal of Adaptive Control and Signal Processing》2020,34(9):1281-1293
This article considers the design of interval functional observers to estimate a linear function of the state vector of time-delay systems subject to both input and output additive disturbances. Two novel functional observers are proposed and designed such that they bound the set of all admissible values of a linear function of the state vector at each instant of time. By contrast to interval observers currently available in the literature, both observers proposed in this article utilize multiple delayed output measurement and have a more general structure. This trade-off feature overcomes some drawbacks in previous work and enables interval functional observers to be designed for a wider class of time-delay systems. Conditions for the existence of interval functional observers are derived and an effective design algorithm for computing unknown observer matrices is provided. Two illustrative examples are given to show the advantages and effectiveness of our design method. 相似文献
85.
Chang-Heon Lee Hyoung-Su Han Seong Hyun Kim Thi Hinh Dinh Chang Won Ahn Jae-Shin Lee 《Journal of Electroceramics》2018,41(1-4):43-49
This study examined the microstructures, crystal structures, and electrical properties of 0.01 mol CuO–added (1–x)(Bi1/2Na1/2)TiO3–xSrTiO3–2BiFeO3 (BNST100x–2BF, x?=?0.20 ~ 0.28) ceramics synthesized at two different sintering temperatures. The sintering temperature of the BNST100x–2BF ceramics could be decreased from 1175 °C to 1000 °C by adding a 0.01 mol CuO excess. Low–temperature sintering led to a decrease in average grain size. The dielectrics, polarization hysteresis (P–E), switching current, and electric–field induced strain (S–E) curves changed with increasing SrTiO3 content and decreasing sintering temperature. Interestingly, the highest reduction ratio of d33* was calculated to be somewhere in between the high–temperature sintered and low–temperature sintered BNST26–2BF ceramics. These results were attributed to the difference in the stabilized relaxor state and closely related to the electric field–induced reversible phase transition from the relaxor and ferroelectrics. 相似文献
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Electronic structure and magnetic properties of Al‐doped Ca2Fe2O5 brownmillerite compounds 下载免费PDF全文
The‐Long Phan Ngo Tran Deok Hyeon Kim Pham T. Tho Bui T. Huy Toan N. Dang Dong‐Seok Yang Bowha Lee 《Journal of the American Ceramic Society》2018,101(5):2181-2189
Polycrystalline Ca2Fe2?xAlxO5 (x = 0‐1.4) samples were prepared by conventional solid‐state reactions. Their crystalline/electronic structures and magnetic properties were characterized in detail. Powder X‐ray diffraction analyses revealed that the samples crystallized in orthorhombic brownmillerite‐type structures with the occurrence of the Pcmn‐Ibm2 phase separation in the region between x = 0.4 and 0.6. The results obtained from analyzing Raman scattering and X‐ray‐absorption fine‐structure spectra also indicated this phase separation. Although x in Ca2Fe2?xAlxO5 varies in a wide range from 0 to 1.4, the +3 oxidation state of Fe remained almost unchanged. Magnetization measurements revealed that all Ca2Fe2?xAlxO5 samples have weak ferromagnetic order, and both the saturation magnetization and coercive force are dependent on the temperature, x, and structure phases. 相似文献
88.
Christopher M. Hope Dao Huynh Ying Ying Wong Helena Oakey Griffith Boord Perkins Trung Nguyen Sabrina Binkowski Minh Bui Ace Y. L. Choo Emily Gibson Dexing Huang Ki Wook Kim Katrina Ngui William D. Rawlinson Timothy Sadlon Jennifer J. Couper Megan A. S. Penno Simon C. Barry 《International journal of molecular sciences》2021,22(17)
Background: Rural/remote blood collection can cause delays in processing, reducing PBMC number, viability, cell composition and function. To mitigate these impacts, blood was stored at 4 °C prior to processing. Viable cell number, viability, immune phenotype, and Interferon-γ (IFN-γ) release were measured. Furthermore, the lowest protective volume of cryopreservation media and cell concentration was investigated. Methods: Blood from 10 individuals was stored for up to 10 days. Flow cytometry and IFN-γ ELISPOT were used to measure immune phenotype and function on thawed PBMC. Additionally, PBMC were cryopreserved in volumes ranging from 500 µL to 25 µL and concentration from 10 × 106 cells/mL to 1.67 × 106 cells/mL. Results: PBMC viability and viable cell number significantly reduced over time compared with samples processed immediately, except when stored for 24 h at RT. Monocytes and NK cells significantly reduced over time regardless of storage temperature. Samples with >24 h of RT storage had an increased proportion in Low-Density Neutrophils and T cells compared with samples stored at 4 °C. IFN-γ release was reduced after 24 h of storage, however not in samples stored at 4 °C for >24 h. The lowest protective volume identified was 150 µL with the lowest density of 6.67 × 106 cells/mL. Conclusion: A sample delay of 24 h at RT does not impact the viability and total viable cell numbers. When long-term delays exist (>4 d) total viable cell number and cell viability losses are reduced in samples stored at 4 °C. Immune phenotype and function are slightly altered after 24 h of storage, further impacts of storage are reduced in samples stored at 4 °C. 相似文献
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The finite element analysis in engineering applications comprises three phases: domain discretization, equation solving and error analysis. The domain discretization or mesh generation is the pre-processing phase which plays an important role in the achievement of accurate solutions. In this paper, the improvement of one particularly promising technique for generating two-dimensional meshes is presented. Our technique shows advantages and efficiency over some currently available mesh generators. 相似文献