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2.
This paper presents a new spatial dependence model with an adjustment of feature difference. The model accounts for the spatial autocorrelation in both the outcome variables and residuals. The feature difference adjustment in the model helps to emphasize feature changes across neighboring units, while suppressing unobserved covariates that are present in the same neighborhood. The prediction at a given unit incorporates components that depend on the differences between the values of its main features and those of its neighboring units. In contrast to conventional spatial regression models, our model does not require a comprehensive list of global covariates necessary to estimate the outcome variable at the unit, as common macro-level covariates are differenced away in the regression analysis. Using the real estate market data in Hong Kong, we applied Gibbs sampling to determine the posterior distribution of each model parameter. The result of our empirical analysis confirms that the adjustment of feature difference with an inclusion of the spatial error autocorrelation produces better out-of-sample prediction performance than other conventional spatial dependence models. In addition, our empirical analysis can identify components with more significant contributions. 相似文献
3.
Y.Pazhuhanfar B.Eghbali 《矿物冶金与材料学报》2021,28(6):1080-1089
In the present research, aluminum metal matrix composites were processed by the stir casting technique. The effects of TiB2 rein-forcement particles, severe plastic deformation through accumulative roll bonding (ARB), and aging treatment on the microstructural charac-teristics and mechanical properties were also evaluated. Uniaxial tensile tests and microhardness measurements were conducted, and the micro-structural characteristics were investigated. Notably, the important problems associated with cast samples, including nonuniformity of the rein-forcement particles and high porosity content, were solved through the ARB process. At the initial stage, particle-free zones, as well as particle clusters, were observed on the microstructure of the composite. However, after the ARB process, fracturing phenomena occurred in brittle ceramic particles, followed by breaking down of the fragments into fine particles as the number of rolling cycles increased. Subsequently, com-posites with a uniform distribution of particles were produced. Moreover, the tensile strength and microhardness of the ARB-processed com-posites increased with the increase in the reinforcement mass fraction. However, their ductility exhibited a different trend. With post-deforma-tion aging treatment (T6), the mechanical properties of composites were improved because of the formation of fine Mg2Si precipitates. 相似文献
4.
教学质量是教育的核心问题。继续教育的质量保障体系建设,既是继续教育服务学生、服务社会经济发展的必然需求,也是普通高校继续教育发展的自身保障。本文紧扣继续教育质量保障体系建设的工作实践,围绕继续教育现状分析、质量保障体系内涵认知、质量保障体系创建举措与特色等方面进行知行合一的研究论述。 相似文献
5.
为更好地将专业教育与思政教育有机融合,充分发挥专业课程的育人功能,各学校积极开展课程思政教学改革试点工作,逐步形成"大思政"教育体系。以专业主干课程软件工程为例,在分析教学内容和目标基础上,从科学素养培养、创新意识强化、生活处事哲理灌输等方面阐述了该课程开展课程思政的着眼点,并分别从教学内容设计、教学方法改革和教学评价改进等方面详细分享了开展课程思政的经验和做法。实践表明,上述措施切实加强了学生科学素养、法治素养、民族自信和创新意识的培养,达到了课程思政教育的目的,取得了较为满意的效果。 相似文献
6.
Samuel Y.M. Ze‐To 《Journal of forecasting》2015,34(5):379-390
I examine the information content of option‐implied covariance between jumps and diffusive risk in the cross‐sectional variation in future returns. This paper documents that the difference between realized volatility and implied covariance (RV‐ICov) can predict future returns. The results show a significant and negative association of expected return and realized volatility–implied covariance spread in both the portfolio level analysis and cross‐sectional regression study. A trading strategy of buying a portfolio with the lowest RV‐ICov quintile portfolio and selling with the highest one generates positive and significant returns. This RV‐Cov anomaly is robust to controlling for size, book‐to‐market value, liquidity and systematic risk proportion. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
Parasites of the grey mullet Mugil cephalus collected from Lower K?z?l?rmak Delta in Turkey were investigated. Trichodina puytoraci, Trichodina lepsii, Ligophorus mediterraneus, Ligophorus cephali, Gyrodactylus sp., Microcotyle mugilis, Ascocotyle (Phagicola) longa, Haplosplanchnus pachysomus, Diplostomum spathaceum, Tylodelphys clavata, Posthodiplostomum sp., Neoechinorhyncus agilis and Ergasilus lizae were identified. Overall infection prevalence (%), mean intensity and mean abundance values were 99.61%, 458.10 ± 75.72 and 456.30 ± 75.44, respectively. Infection indices of parasite species in relation to season, lakes/lagoons and some physicochemical parameters of water such as temperature, salinity, dissolved oxygen and nitrate are determined and discussed. Posthodiplostomum sp. is a new parasite record for mugilids and Diplostomum spathaceum is the first record in M. cephalus, in the present study. Moreover, Ligophorus mediterraneus, Ligophorus cephali and Ergasilus lizae are new records for Turkish parasite fauna of fish and Mugil cephalus is a new host record for Neoechinorhyncus agilis in Turkey. 相似文献
8.
正Published online:14 March 2014óScience China Press and Springer-Verlag Berlin Heidelberg 2014Erratum to:Chin.Sci.Bull.(2014)59(5–6):528–532DOI 10.1007/s11434-013-0060-1In the original publication of this paper,the first name and the last name of the first author has been documented 相似文献
9.
The Wnt/beta-catenin/TCF4 pathway plays critical roles in the maintenance of small intestinal epithelium; however, downstream
targets of the beta-catenin/TCF4 complex are not extensively characterized. We identified miR-30e as an immediate target activated
by the beta-catenin/TCF4 complex. miR-30e was detected in the peri-nuclear region of the intestinal crypt IEC-6 cells. Bioinformatics
analysis revealed clustered beta-catenin/TCF4 binding sites within the miR-30e promoter region. This promoter region was cloned
into pGL3-control luciferase reporter vector, with the enhancer region removed. Transfection of pCMV-SPORT6-beta-catenin expression
vector dose-dependently increased luciferase activity, and co-transfection of pCMV-SPORT6-TCF4 expression vector further enhanced
the promoter activity. Dexamethasone-induced IEC-6 cells differentiation caused a 2.5-fold increase in miR-30e expression,
and upon beta-catenin siRNA transfection, miR-30e increased 1.3-fold. Electrophoretic mobility shift assay and chromatin immunoprecipitation
assay confirmed the binding between beta-catenin/TCF4 complexes from IEC-6 nuclear extracts and the putative sequences in
the miR-30e promoter. These results demonstrate that beta-catenin/TCF4 transactivates miR-30e during intestinal cell differentiation. 相似文献
10.
针对在非合作突发通信信号检测中,已有的各种检测方法均未能充分利用信号的频域连续性的问题,提出了一种新的检测方法,利用信号的频域连续性,在频率和带宽二维进行频域能量累积,搜索最大值并检测.理论分析和仿真均验证了此方法优于Power-Law方法 2 dB以上. 相似文献