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  • Author: Li Feng x
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Abstract

Aiming at the problem of inaccurate and time-consuming of the fault diagnosis method for large-scale ship engine, an intelligent diagnosis method for large-scale ship engine fault in non-deterministic environment based on neural network is proposed. First, the possible fault of the engine was analyzed, and the downtime fault of large-scale ship engine and the main fault mode were identified. On this basis, the fault diagnosis model for large-scale ship engine based on neural network is established, and the intelligent diagnosis of engine fault is completed. The experiment proved that the proposed method has high diagnostic accuracy, engine fault diagnosis takes only about 3s, with a higher use value.

Abstract

Objective To investigate the clinical application of Real-Time PCR for rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) directly from nasopharyngeal swab specimens.

Methods We collected the nasal and throat swab specimens from patients or medical staffs in 3 intensive care units, blood laminar flow ward and respiratory ward in Beijing Hospital, Ministry of Health from December 2010 to April 2011. Each sample was tested by RT-PCR and conventional culture-based method for the presence of MRSA.

Results The total number of the specimens was 206. Compared with the conventional culture-based method, we demonstrated the diagnostic values for Real-Time PCR were 96.4% sensitivity, 96.6% specificity, 81.8% positive predictive rate, and 99.4% negative predictive rate. And the limit of detection was 102CFU/ml.

Conclusions This Real-Time PCR is a simple, rapid, sensitive and specific method. With the high negative predictive value, it can be used for the exclusion of MRSA colonization or infection. However, the application of its low positive predictive value should be further evaluated.

Summary

The width of cut tobacco strands is an important indicator for physical parameters as well as for the smoking quality. In some countries, cut width helps to distinguish fine-cut tobacco and pipe tobacco and thus differentiates taxation rate. A new method for rapid measurement of the width of cut tobacco strands was developed based on digital image processing, because the method described in ISO 20193, though easy to implement in factories, proved time consuming and generated high testing costs. The essence of this method is to determine the statistic width of incisions. The straight-line segments represent the width of strands of cut tobacco, from which the determination of the width for randomly placed tobacco strands could be achieved. Five kinds of samples (‘ISO collaborative study samples 0.4 mm, 1.0 mm, 1.6 mm and 3.0 mm’ and ‘Guangdong baked 0.9 mm’) were used to study the comparability of the measurement results between the method presented in this work and the current ISO method. Results show that accuracy and repeatability are comparable. In addition, the testing efficiency of the method presented in this work appears to be higher than the current ISO method, and it is thus a promising alternative method for measuring the width of strands of cut tobacco.

Abstract

Objective To investigate the relationship between single nucleotide polymorphisms (SNPs) of the interleukin-4 (IL-4) gene and outcome of hepatitis B virus (HBV) infection in a Chinese Han population.

Methods Total of 501 patients with chronic hepatitis B virus (HBV) infection and 301 controls with selflimiting HBV infection were studied. Three tag SNPs in the IL-4 gene (rs2227284G/T, rs2243283C/G and rs2243288A/G) were genotyped by the Multiplex snapshot technique. The genotype and allele frequencies were calculated and analyzed.

Results The three SNPs showed no significant genotype/allele associations with chronic HBV infection. Overall allele P values were: rs2227284, P = 0.655, odds ratio (OR) [95% confidence interval (CI)] = 1.070 (0.793-1.445); rs2243283, P = 0.849, OR (95% CI) = 0.976 (0.758-1.257); rs2243288, P = 0.659, OR (95% CI) = 1.060 (0.818-1.375). Overall genotype P values were: rs2227284, P = 0.771; rs2243283, P = 0.571; rs2243288, P = 0.902. There were no statistically significant differences between patients with chronic HBV infection and controls. Haplotypes generated by these three SNPs also had no significant differences between the two groups.

Conclusions The three tag SNPs of IL-4 were not associated with the outcome of HBV infection in the Han Chinese population.

Abstract

Objective

The aim of this study was to explore whether positive emotion mediates the relationship between job burnout and turnover intentions among Chinese nurses.

Methods

A cross-sectional survey was conducted in the present study. Full-time registered nurses (n = 150) from Grade A hospitals in Tianjin were surveyed. Pearson correlation, hierarchical regression analyses, and the Sobel test were used in the study.

Results

The results illustrated that positive emotion mediated the relationship between burnout and nurses’ turnover intention.

Conclusions

Nursing administrators should pay more attention to the benefits of positive emotions on working motivation. It is helpful to relieve burnout in the working process so that nurses are willing to remain in their current employment.

Abstract

Hexagonal high temperature phase β-Co2P nanorods with a diameter of around 50 nm were synthesized via a mild solvothermal route. The reaction was carried out at 180 °C using cobalt chloride hexahydrate (CoCl2 · 6H2O) as Co source and yellow phosphorous as P source. The composition, structure as well as morphology were characterized by X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS) and transmission electron microscopy (TEM). The magnetic susceptibility curve indicates that the β-Co2P nanorods show canted antiferromagnetic state, different from the paramagnetic state of orthorhombic low temperature phase β-Co2P.

Abstract

Objective

The objective of this study was to discuss the effect of double perfusion cannula accompanied with low negative pressure drainage in the treatment of complexity of abdominopelvic and perineal infections.

Methods

The technology of the double perfusion cannula accompanied with low negative pressure drainage was used to treat complexity of abdominopelvic and perineal infections.

Results

Double perfusion cannula accompanied with low negative pressure drainage can be applied to the treatment of complexity of abdominopelvic and perineal infections. It has an obvious effect on infection control and reduces recovery time.

Conclusion

Double perfusion cannula accompanied with low negative pressure drainage has a good effect on complexity of abdominopelvic and perineal infections; it can be used in wider surgical fields to prevent infections.

Abstract

Objective To detect the values of NT-proBNP and evaluate its relationship with liver function, cardiac structure, and cardiac function which was evaluated by echocardiography in patients with liver cirrhosis.

Methods A total of 50 liver cirrhotic patients and 11 healthy controls were studied by two dimensional Doppler echocardiography. Liver cirrhotic patients were divided into group A, B and C according to the Child-Pugh score. Cardiac dimensions and left and right ventricular functions were also evaluated. At the same time, the serum NTproBNP of liver cirrhotic patients and healthy controls were detected, respectively.

Results By Comparison between two groups, we found that the values of LVd, LAs, LVPW, AAO, A Wave, RVOTs, PV and NT-proBNP in liver cirrhosis group were higher than those in control group, whereas the value of E/A decreased. As for the value of LAs and serum NT-proBNP, A and B group were all lower than C group. With LAs > 35 mm, the number of cases in liver cirrhosis group was higher than that in control group. So did that With E/A < 1.

Conclusions The cardiac dysfunction confirmed the existence of cirrhotic cardiomyopathy. More clinical implications were found in liver cirrhotic patients with increased values of serum NT-proBNP.

Abstract

In order to solve the computing speed and efficiency problem of existing dynamic clothing simulation, this paper presents a dynamic garment simulation based on a hybrid bounding volume hierarchy. It firstly uses MCASG graph theory to do the primary segmentation for a given three-dimensional human body model. And then it applies K-means cluster to do the secondary segmentation to collect the human body’s upper arms, lower arms, upper legs, lower legs, trunk, hip and woman’s chest as the elementary units of dynamic clothing simulation. According to different shapes of these elementary units, it chooses the closest and most efficient hybrid bounding box to specify these units, such as cylinder bounding box and elliptic cylinder bounding box. During the process of constructing these bounding boxes, it uses the least squares method and slices of the human body to get the related parameters. This approach makes it possible to use the least amount of bounding boxes to create close collision detection regions for the appearance of the human body. A spring-mass model based on a triangular mesh of the clothing model is finally constructed for dynamic simulation. The simulation result shows the feasibility and superiority of the method described.

Abstract

In order to improve the performance of tracking, we propose a new online tracking method based on classification and adaptive fused feature. We first label a few positive and negative samples, train the classifier by the online SSSM (Semi-Supervised Support Vector Machine) learning and these labelled samples, and then locate the position of the object from the next frame according to the trained classifier. In order to adapt more of the new samples, we need to update the classifier by finding new samples with high confident value obtained by the trained classifier and add them into the online SSSM. Finally we also update the object model by the online incremental PCA (Principal Component Analysis) because of background clutter, heavy occlusion and complicated object appearance changes. Compared with the basic mean shift tracking and the ensemble tracking method, experimental results show that our tracking method is able to effectively handle heavy occlusion and background clutter in some challenge videos including some thermal videos.