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In order to improve the ideological understanding of computer majors and establish a correct world outlook, outlook on life and values, the ideological and political goals of computer majors are designed; (1) A new deep learning face recognition algorithm is proposed. Aiming at the limitations of many current methods of artificially designing image description features, this algorithm proposes an unsupervised big data-driven deep image feature learning and representation mechanism. (2) A new idea of single-target tracking algorithm DPL is proposed. Single target tracking is a hot research topic in the field of computer anxiety. Our proposed DPL algorithm is still very competitive with the best algorithms in the field of object tracking. Several key technology research and model design schemes for computer major courses are proposed, which enriches the relevant research content of deep learning in the field of computer vision, and has certain theoretical and practical significance.

The aim of this study was to explore the application effect of thoracic computerized tomography (CT) under single threshold segmentation algorithm in the diagnosis of heart failure (HF) complicated with sleep apnea syndrome. 30 patients diagnosed with HF complicated with sleep apnea syndrome were chosen for the research. Another 30 patients without sleep apnea syndrome were selected as the control group, whose age, height, and weight were similar to those of the experimental group. Then, a model for thoracic CT image segmentation was proposed under the single threshold segmentation algorithm, and the faster region convolutional neural network (Faster RCNN) was applied to label the thoracic respiratory lesions. All the patients underwent thoracic CT examination, and the obtained images were processed using the algorithm model above. After that, the morphology of the patient’s respiratory tract after treatment was observed. The results suggested that the improved single threshold segmentation algorithm was effective for the image segmentation of patient lesions, and the Faster RCNN could effectively finish the labeling of the lesion area in the CT image. The classification accuracy of the Faster RCNN was about 0.966, and the loss value was about 0.092. With CT scanning under the algorithm, it was found that the airway collapse of the posterior palatal area, retrolingual area, and laryngopharyngeal area of the sleep apnea syndrome patients was significantly greater than that of the control group ( P < 0.05 ). But there was no significant difference of the collapse of the nasopharyngeal area between the two groups ( P > 0.05 ). The single threshold segmentation algorithm had a better segmentation accuracy for thoracic CT images in patients with HF and sleep apnea syndrome, so it had a highly promising application prospect in the diagnosis of the disease.

Al/Cu dissimilar joint has been widely produced by using friction stir welding (FSW), but the weld quality remains limited. A recently developed ultrasonic vibration-assisted FSW (UVaFSW) technology has shown potential of enhancing the material flow and mechanical properties of Al/Cu joint. In this paper, a systematic study is presented to investigate the effect of ultrasonic energy on FSW Al/Cu joints with an optimized tool shoulder diameter of 16 mm and welding speed of 60 mm/min. It is found that the thermal effect of ultrasonic on the FSW process could be deemed negligible, which is distinguishing with other transmission method of ultrasonic energy. Correspondingly, the mechanical effect of ultrasonic is evident because of the dramatically decreased welding loads, the more intense intermixing between Al and Cu, and the more uniformly distributed micro-hardness in the stirring zone of UVaFSW Al/Cu joints. Moreover, the ultrasonic energy reveals a positive influence on the weld quality of Al/Cu joint; the maximum tensile strength by UVaFSW is achieved at the rotation speed of 500 rpm; and the value reaches 162.8 MPa, which improves by 60.7% compared with that by FSW. It is elucidated that the ultrasonic vibration effectively reduces the activation energy and flow stress of the material, stimulates stable plastic deformation in the vicinity of the tool, and is beneficial for the homogeneous of FSW Al/Cu joint.

Dissimilar aluminium alloy and pure copper joints were produced using a novel ultrasonic vibration assisted friction stir welding (UVaFSW) assembly. The intermetallic compounds (IMCs) formed at the Al-Cu interfaces were characterized using a scanning electron microscope and energy-dispersive X-ray spectroscopy analysis. The thermodynamic prediction of the first intermetallic compound formation using effective Gibbs free energy change of formation (EGFEF) model was used to calculate the first intermetallic compound layer to nucleate or form during each process condition at the joint interface. The results show that irrespective of the welding conditions (with and without ultrasonic vibrations) intermetallic compounds are formed at the interface. However, the ultrasonic vibration effectively reduced the thickness of the IMC layer at the joint interface and consequently improved the mechanical properties of the joints.

Two kinds nitride modified layers were obtained on Ti-13Nb-13Zr surface to improve the wear property via magnetron sputtering and plasma nitriding techniques, respectively. The structures of the modified layer and the worn surface after sliding test were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The friction and wear behavior of the modified layer against alumina ball was investigated in the absence of lubricant under different loads (1 N and 2 N). The X-ray diffraction analysis reveals that nitride layer is mainly composed of TiN and Ti2N, while coating film consists of TiN phase. Friction and wear test indicates that both modified layers can improve the wear resistance compared to untreated Ti-13Nb-13Zr. TiN thin film produces very hard surface, but may be easy to cause coating fracture and delamination under high normal load. However, nitride layer exhibits better wear performance. This is attributed to hard compound layer maintained its integrity with the hardened nitrogen diffusion zone during friction and wear process.

The arrival of the information age has created a more suitable for the social development of the era of big data. Under the new normal, the era of big data increasingly needs all-round, talented and innovative talents. And in recent years with the continuous development of electronic information technology, China’s e-commerce development by leaps and bounds. The purpose of this paper is to build a more information-based teaching system of website construction for e-commerce major through the combination of big data technology. Based on the background of the era of big data, this paper puts forward the view of carrying out educational information reform in colleges and universities, and puts forward a new idea of building a teaching model based on information management. It includes the following points: strengthening the construction of standard system of educational informatization, promoting the effective integration of educational information system, improving the overall information literacy of educational managers, promoting the construction of educational management information and the establishment of a new teaching model based on it. This paper mainly adopts the method of literature analysis, questionnaire survey and educational statistics to study the teaching situation of website construction of 160 soprano students majoring in e-commerce in a university. After three months of teaching, the students’ general performance has increased by about 6%. Based on this, I hope to provide some Suggestions for data teaching and professional development and improvement under the background of big data.

Diabetes mellitus has potential to alter the toxicity of hazardous chemicals. Dichloroacetonitrile (DCAN) is one of high-risk nitrogenous disinfection by-products. This study evaluated the neurotoxicity of DCAN (11, 44 and 88mg/kg) in normoglycaemic and streptozotocin (STZ)-induced diabetic rats via orally for 28days. STZ diabetes prolonged the median survival time and total lethal time after DCAN (88mg/kg) exposure when compared with that observed in normoglycaemic rats. DCAN altered motor activity and induced anxiety behaviour in normoglycaemic rats; but it did not exaggerate behavioural changes in STZ diabetic rats. DCAN -induced brain oxidative damage by compensatory increase glutathione content and decrease malonaldehyde levels; but it did not induce oxidative damage in diabetic rats. STZ diabetes slowed down the pathological pace of DCAN-induced brain mitochondrial dysfunction by decreasing reactive oxygen species and increasing cytochrome C oxidase activity. In conclusion, the present study indicated that STZ diabetic rats are resistant to DCAN-induced neurotoxicity at the dosage and with the dosage schedule in 28-day subacute toxicity test.

A blending method for generating initial condition (IC) perturbations in a regional ensemble prediction system is proposed. The blending is to combine the large-scale IC perturbations from a global ensemble prediction system (EPS) with the small-scale IC perturbations from a regional EPS by using a digital filter and the spectral analysis technique. The IC perturbations generated by blending can well represent both large-scale and small-scale uncertainties in the analysis, and are more consistent with the lateral boundary condition (LBC) perturbations provided by global EPS. The blending method is implemented in the regional ensemble system Aire Limitée Adaptation Dynamique Développement International-Limited Area Ensemble Forecasting (ALADIN-LAEF), in which the large-scale IC perturbations are provided by the European Centre for Medium-Range Weather Forecasts (ECMWF-EPS), and the small-scale IC perturbations are generated by breeding in ALADIN-LAEF. Blending is compared with dynamical downscaling and breeding over a 2-month period in summer 2007. The comparison clearly shows impact on the growth of forecast spread if the regional IC perturbations are not consistent with the perturbations coming through LBC provided by the global EPS. Blending can cure the problem largely, and it performs better than dynamical downscaling and breeding.

One of the main challenges for a skilful Limited Area Model Ensemble Prediction System (LAMEPS) is the generation of appropriate initial perturbations. In most operational LAMEPSs, the initial perturbations are provided by a global Ensemble Prediction System (EPS). Molteni et al. (2001) proposed clustering analysis as an objective selection criterion to choose a member from the global European Centre for Medium-range Weather Forecasts (ECMWF)-EPS model as initial perturbations in LAMEPS. In this article, another strategy for using the clustering method is investigated which ensures that initial perturbations are centred on the control analysis. The main purpose of this article is to study the benefit of cluster analysis and to validate the effect of different clustering strategies on the performance of a 17-member LAMEPS. The system used in this study is the operational Aire Limitee Adaptation Dynamique Developpement InterNational-Limited-Area Ensemble Forecasting (ALADIN-LAEF) model. Three experiments we...

The Central European limited-area ensemble forecasting system ALADIN-LAEF (Aire Limitee Adaptation Dynamique Developpement InterNational—Limited-Area Ensemble Forecasting) has been developed within the framework of ALADIN international cooperation and the Regional Cooperation for Limited-Area modelling in Central Europe (RC LACE). It was put into pre-operation in March 2007. The main feature of the pre-operational ALADIN-LAEF was the dynamical downscaling of the global ensemble forecast from the European Centre for Medium-range Weather Forecasts (ECMWF). In 2009, ALADIN-LAEF was upgraded with several methods for dealing with the forecast uncertainties to improve the forecast quality. These are: (1) the blending method, which combines the large-scale uncertainty generated by ECMWF singular vectors with the small-scale perturbations resolved by ALADIN breeding into atmospheric initial condition perturbations; (2) the multi-physics approach, wherein different physics schemes are used for different forecast members to account for model uncertainties; and (3) the non-cycling surface breeding technique, which generates surface initial condition perturbations. This article illustrates the technical details of the updated ALADIN-LAEF and investigates its performance. Detailed verification of the upgraded ALADIN-LAEF and a comparison with its first implementation (dynamical downscaling of ECMWF ensemble forecasts) are presented for a two-month period in summer 2007. The results show better performance and skill for the upgraded system due to the better representation of forecast uncertainties. Copyright © 2011 Royal Meteorological Society

The activation of the NF-κB signaling pathway plays a critical role in carcinogenesis. The role of the NF-κB pathway in esophageal squamous cell carcinoma (ESCC) remains ill-defined. The objective was to detect whether p65siRNA and curcumin could promote ESCC cell apoptosis and increase the sensitivity of ESCC cells to chemotherapeutic drugs by inhibiting the NF-κB signaling pathway, and to compared these two treatments. In the present study, the status of the NF-κB pathway, in the two ESCC cell lines Eca109 and EC9706, was analyzed and the ability of p65 siRNA and curcumin alone or in combination with 5-FU to modulate this pathway in vitro and in vivo was investigated. The results showed that the NF-κB signaling pathway in the ESCC cell lines was constitutively activated. Both p65 siRNA and curcumin mediated suppression of activation of the NF-κB signaling pathway via inhibition of the expression of p65 or IκBα phosphorylation in ESCC cell lines. The cells treated with combination of p65 siRNA or curcumin and 5-FU revealed a lower cell viability and higher apoptosis compared to those treated with 5-FU alone. In a human ESCC xenograft model, p65 siRNA or curcumin and 5-FU alone reduced the tumor volume, respectively, but their combination had the strongest anticancer effects. Curcumin was more effective than p65 siRNA in vitro and in vivo. Overall, our results indicate that the constitutively activated NF-κB signaling pathway plays a crucial role in these two ESCC cell lines and both p65siRNA and curcumin can promote ESCC cell apoptosis and enhance the sensitivity to 5-FU through suppression of the NF-κB signaling pathway. It is still a long time before RNA interference will be used in the clinic. Therefore, curcumin is proved to be useful in the treatment of ESCC as it is a pharmacologically safe compound without side effects.