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991.
Zhiyuan Chen Le Dinh Van Khoa Ee Na Teoh Amril Nazir Ettikan Kandasamy Karuppiah Kim Sim Lam 《Knowledge and Information Systems》2018,57(2):245-285
Money laundering has been affecting the global economy for many years. Large sums of money are laundered every year, posing a threat to the global economy and its security. Money laundering encompasses illegal activities that are used to make illegally acquired funds appear legal and legitimate. This paper aims to provide a comprehensive survey of machine learning algorithms and methods applied to detect suspicious transactions. In particular, solutions of anti-money laundering typologies, link analysis, behavioural modelling, risk scoring, anomaly detection, and geographic capability have been identified and analysed. Key steps of data preparation, data transformation, and data analytics techniques have been discussed; existing machine learning algorithms and methods described in the literature have been categorised, summarised, and compared. Finally, what techniques were lacking or under-addressed in the existing research has been elaborated with the purpose of pinpointing future research directions. 相似文献
992.
993.
Microsystem Technologies - In this work, we investigated how elastomeric mold properties could affect the final replication accuracy in hot roller embossing. Amorphous polyethylene terephthalate... 相似文献
994.
Pre‐natal and post‐natal exposure to pet ownership and lung function in children: The Seven Northeastern Cities Study 下载免费PDF全文
L.‐W. Hu Z. Qian S. C. Dharmage E. Liu S. W. Howard M. G. Vaughn J. Perret C. C. Lodge X.‐W. Zeng B.‐Y. Yang S.‐L. Xu C. Zhang G.‐H. Dong 《Indoor air》2017,27(6):1177-1189
To evaluate the association between pre‐natal and post‐natal exposure to pet ownership and lung function in children, a cross‐sectional study named Seven Northeastern Cities (SNEC) study was conducted. In this study, children's lung function including the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), maximal mid‐expiratory flow (MMEF), and peak expiratory flow (PEF) were measured by spirometers, and pet ownership situations were collected by questionnaire. Analyzed by multiple logistic regression and generalized linear modeling, we found that for all subjects, pet exposure in the first 2 years of life was significantly associated with lung function impairment of FVC<85% predicted (adjusted odds ratio [aOR]=1.28; 95% confidence interval [CI]: 1.01, 1.63). For current pet exposure, the increased odds of lung function impairment ranged from 35% (aOR=1.35; 95%CI: 1.12, 1.62) for FVC<85% predicted to 57% (aOR=1.57; 95%CI: 1.29, 1.93) for FEV1<85% predicted. The in utero exposure was not related to lung function impairment. Compared with other pets, higher odds were observed among children with dogs. When stratified by gender, girls with current pet exposure were more likely to have lung function impairment than boys. It implies self‐reported exposures to pets were negatively associated with lung function among the children under study. 相似文献
995.
L. K. Ji T. Xu J. M. Zhang H. T. Wang M. X. Tong R. H. Zhu G. S. Zhou 《Journal of Materials Engineering and Performance》2017,26(7):3104-3111
Tensile properties of the high-deformability dual-phase ferrite-bainite X70 pipeline steel have been investigated at room temperature under the strain rates of 2.5 × 10?5, 1.25 × 10?4, 2.5 × 10?3, and 1.25 × 10?2 s?1. The microstructures at different amount of plastic deformation were examined by using scanning and transmission electron microscopy. Generally, the ductility of typical body-centered cubic steels is reduced when its stain rate increases. However, we observed a different ductility dependence on strain rates in the dual-phase X70 pipeline steel. The uniform elongation (UEL%) and elongation to fracture (EL%) at the strain rate of 2.5 × 10?3 s?1 increase about 54 and 74%, respectively, compared to those at 2.5 × 10?5 s?1. The UEL% and EL% reach to their maximum at the strain rate of 2.5 × 10?3 s?1. This phenomenon was explained by the observed grain structures and dislocation configurations. Whether or not the ductility can be enhanced with increasing strain rates depends on the competition between the homogenization of plastic deformation among the microconstituents (ultra-fine ferrite grains, relatively coarse ferrite grains as well as bainite) and the progress of cracks formed as a consequence of localized inconsistent plastic deformation. 相似文献
996.
R. Cao J. J. Yuan Z. G. Xiao J. Y. Ma G. J. Mao X. B. Zhang J. H. Chen 《Journal of Materials Engineering and Performance》2017,26(6):2472-2483
In this paper, the sources of variability and lower values in toughness measurements of a high-strength low alloy weld metal are investigated by detailed observations of fracture surfaces and the microstructures at crack initiation. The results reveal that the variability of the notch Charpy toughness is related to the location of the cleavage initiation origins. The three factors jointly contribute to give rise to variability and lower value of toughness. That is, (1) the location that the notch is sampled at deposited weld metal or reheated weld metal, (2) the location that a large grain region is appeared on the path ahead of the notch root, (3) the distributed location of the defect or the brittle second-phase particle. When three factors were simultaneously satisfied, the lower value of the Charpy toughness is appeared. The notch is sampled at the largest grain region at deposited weld metal, and the defect or the brittle second-phase particle is close to the notch root and sampled by its high stress field, the lowest Charpy toughness is obtained. 相似文献
997.
X. Artru S.P. Fomin N.F. Shulga 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):476-482
The results of theoretical investigation of angular distributions of radiation from a relativistic electron passing through a thin crystal at a small angle to the crystal axis are presented. The electron trajectories in crystal were simulated using the binary collision model which takes into account both coherent and incoherent effects at scattering. The angular distribution of radiation was calculated as a sum of radiation from each electron. It is shown that there are non-trivial angular distributions of the emitted photons, which is connected to the superposition of the coherent scattering of electrons by atomic rows (“doughnut scattering” effect) and the suppression of the radiation due to the multiple scattering effect (similar to the Landau–Pomeranchuk–Migdal effect in an amorphous matter). The orientation dependence of angular distribution of radiation is also analyzed. 相似文献
998.
Q.X. Yang W.L. Zhao Y.S. Wang Y.T. Song S.S. Du J.S. Hu G.Z. Zuo J.G. Li L.E. Zakharov 《Fusion Engineering and Design》2013,88(9-10):1646-1649
Lithium is a very attractive element due to its very low radiation power, strong H retention as well as strong O getter activity. Flowing liquid lithium (FLiLi) device, to be used as a plasma-facing limiters, has been designed and will be tested in HT-7 tokamak. It is mainly composed of distributor, guide plate, collector, and heater as well as cooling loop. The heater uses heater strip and cooling loop design, to control the temperature of lithium on the guide plate ranging from 200 °C to 400 °C. The distributor attached to feeding pipe, distributes liquid lithium (LiLi) flowing on the guide plate. The collector was designed to reclaim the superfluous LiLi and transport it out of device.The paper focuses on the design of flowing liquid lithium device. In addition to the process of design, thermal analysis has been carried out using finite element method (FEM) for optimizing the structure of heater and cooling loop and results of analysis are presented. 相似文献
999.
Helium atoms, introduced into materials by helium plasma or generated by the (n, α) nuclear reaction, have a strong tendency to accumulate at trapping sites such as vacancy clusters and dislocations. In this paper, the effects of dislocations, single vacancies and vacancy clusters on the retention and desorption of helium atoms in nickel were studied. Low energy (0.1-0.15 keV) helium atoms were implanted in nickel with vacancies or dislocations without causing any displacement damage. He atoms, interstitial-type dislocation loops, and vacancy clusters were also introduced with irradiation damage by 5.0 keV helium ions. Helium thermal desorption peaks from dislocations, helium-vacancy clusters and helium bubbles were obtained by thermal desorption spectroscopy at 940 K, in the range from 900 to 1370 K, and at 1500 K, respectively. In addition, a thermally quasi-stable state was found for helium-vacancy clusters. 相似文献
1000.
Al2O3–14 wt%B4C composites with 0–1 wt% C addition were sintered in Ar at 1550–1650 °C. The influence of the C additive on the B loss, densification behavior, and microstructure of the Al2O3–B4C composites were investigated. The results show that there are B2O3, H3BO3 and Al18B4O33 exist between Al2O3 and B4C interface, which result in B loss because of B2O3's high vapor tension at above 1500 °C. The presence of Al18B4O33 grains formed by chemical reaction of Al2O3 with surface oxides on B4C inhibit the densification of pellets by reducing the specific free surface energy of the Al2O3. However, the added C eliminates those oxides to reduce B loss because of its higher activity than B4C, and it also coarsens Al2O3 grain although the density of pellets is decreased by gas products. 相似文献