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31.
This article presents a multi-dimensional spatial pattern analysis of crime events in San Francisco. Our analysis includes the impact of spatial resolution on hotspot identification, temporal effects in crime spatial patterns, and relationships between various crime categories. In this work, crime prediction is viewed as a classification problem. When predictions for a particular category are made, a binary classification-based model is framed, and when all categories are considered for analysis, a multiclass model is formulated. The proposed crime-prediction model (HotBlock) utilizes spatiotemporal analysis for predicting crime in a fixed spatial region over a period of time. It is robust under variation of model parameters. HotBlock's results are compared with baseline real-world crime datasets. It is found that the proposed model outperforms the standard DeepCrime model in most cases.  相似文献   
32.
Crime is not a completely random event but rather shows a pattern in space and time. Capturing the dynamic nature of crime patterns is a challenging task. Crime prediction models that rely only on neighborhood influence and demographic features might not be able to capture the dynamics of crime patterns, as demographic data collection does not occur frequently and is static. This work proposes a novel approach for crime count and hotspot prediction to capture the dynamic nature of crime patterns using taxi data along with historical crime and demographic data. The proposed approach predicts crime events in spatial units and classifies each of them into a hotspot category based on the number of crime events. Four models are proposed, which consider different covariates to select a set of independent variables. The experimental results show that the proposed combined subset model (CSM), in which static and dynamic aspects of crime are combined by employing the taxi dataset, is more accurate than the other models presented in this study.  相似文献   
33.
Multimedia Tools and Applications - GAN-based image colorization techniques are capable of producing highly realistic color in real-time. Subjective assessment of these approaches has demonstrated...  相似文献   
34.

We report the fluorescence properties of samarium (III) ions in fluoro-borate glasses (Sm3+:BCNF) which were examined through X-ray diffraction, Fourier transform infrared, and UV–Vis–NIR spectroscopy. From the absorption spectra, Judd–Ofelt intensity parameters were determined, which are in turn used to evaluate several radiative properties for the various excited states of samarium (III) ions. The emission spectrum was used to calculate the effective bandwidth (Δλeff) and empirical branching ratios (βexp). With increasing concentrations of samarium (III) ions, the luminescence decay patterns of the 4G5/2 transition became double exponential. The Inokuti–Hirayama model for S?=?6 has been used to explain the double-exponential behavior of decay time profiles, revealing that the energy transmission mechanism between the samarium (III) ions are dipole–dipole.

  相似文献   
35.
Two-dimensional numerical simulations are carried out to understand the effects of cross-buoyancy on the confined flow and heat transfer characteristics over an equilateral triangular bluff body at low and intermediate Reynolds numbers (Re). For a fixed Richardson number (Ri), an average cylinder Nusselt number increases with increasing Re. However, the average Nusselt number shows a soft response toward increasing Ri. The critical Re for the onset of periodic unsteady flow increases with increasing cross-buoyancy (Ri). A simple heat transfer correlation is also obtained to relate the values of average cylinder Nusselt number, Re, and Ri.  相似文献   
36.
Hyperlipidemia is associated with increased risk of atherosclerosis; therefore, control of this risk factor is very important in preventing atherosclerosis. Cucumber (Cucumis sativus) seed is used traditionally as a lipid‐lowering nutritional supplement. The aim of this study was to evaluate the effect of cucumber seed extract on serum lipid profile in adult patients with mild hyperlipidemia. In a randomized double‐blind placebo‐controlled clinical trial, hyperlipidemic patients with inclusion criteria were randomly and equally assigned to either Cucumis or placebo groups and used one medicinal or placebo capsule, respectively, once daily with food for 6 wk. Body mass index (BMI) as well as fasting serum levels of total cholesterol, triglycerides (TG), low‐density lipoprotein (LDL‐C), and high‐density lipoprotein (HDL‐C) were measured for all patients pre‐ and post‐intervention and finally the changes were compared between the groups. Twenty‐four patients in Cucumis group and 23 patients in placebo group completed the study. Cucumis seed extract resulted in significant reduction of total cholesterol (P = 0.016), LDL‐C (P < 0.001), TG (P < 0.001), and BMI (P < 0.001) as well as significant increase of HDL‐C (P = 0.012) compared to placebo. In conclusion, the consumption of C. sativus seed extract with daily dose of 500 mg results in desirable effects on serum lipid profile in adult hyperlipidemic patients. Therefore, cucumber seed could be considered as a food supplement for treatment of dyslipidemia.  相似文献   
37.
Abstract

Frequency, amplitude, and phase information of the grid voltage are the main constraints for constructing a robust controller algorithm for grid connected applications under unbalanced and distorted voltage conditions. This paper narrates a simple, robust, straight forward method to estimate the instantaneous positive and negative sequence voltage components under unbalanced and distorted voltage circumstances. A second order generalized integrator (SOGI) is encapsulated to filter out the distorted voltage as well as to generate orthogonal voltage components for the three phases of AC grid. Furthermore, these filtered and orthogonal components are accounted for the calculation of instantaneous symmetrical components. Developed technique is more frequency adaptive compared to conventional phase locked loop (PLL) techniques. A set of test outcome results are provided in this paper based on MATLAB/Simulink simulations with real grid data captured from an industrial plant. Moreover, SOGI based estimator is digitally implemented by using dSPACE ds1103 digital controller to validate the numerical simulation results in accordance with the developed theoretical prediction.  相似文献   
38.
Promoters are the most important tools to control and regulate the gene expression in synthetic biology and met-abolic engineering. The expression of target genes in Escherichia coli is usually control...  相似文献   
39.
Properties such as high hardness, low density, and high elastic modulus have made SiC ceramics proper choices for a variety of industrial applications. However, disadvantages such as low sinterability, and low fracture toughness have limited the fabrication of these ceramics. Past researches show that the use of Al2O3-Y2O3 additives play an important role in improving the sinterability and the properties of the composites. The use of oxide, carbide, nitride and boride additives results in improved sinterability, physical and mechanical properties. The investigations show that the microstructure, porosities, amount of additives, reaction of additives with the matrix, grain size and, finally, the sintering temperature are the most important factors affecting the properties of SiC ceramics. In this paper, the effect of using various additives, the sintering temperature and the annealing heat treatment on sinterability, microstructure and properties of the SiC matrix composites fabricated by pressureless sintering method have been investigated.  相似文献   
40.
The polymer metal complexes of transition metal ions Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with a new polymeric Schiff base containing formaldehyde and piperazine moieties have been synthesized by the condensation and characterized by elemental analyses, infrared spectra, electronic spectra, magnetic susceptibility measurements and thermogravimetric analyses (TGA). The results of the electronic spectra and magnetic moments indicate that the polymer–metal complexes of Mn(II), Co(II) and Ni(II) have octahedral geometry, while the complexes of Cu(II) and Zn(II) show square planar and tetrahedral geometry, respectively. The analyses of the thermal curves of all the polymer metal complexes show better thermal stability than the polymeric Schiff base. All compounds show excellent antibacterial as well as antifungal activity against three types of bacteria and two types of fungi. The antimicrobial activities were determined by using the agar well diffusion method with 100 μg/mL concentrations of polymer metal complex.  相似文献   
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