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Open access

Yanzhe Hu, Mengjie Xu and Yang Li

Abstract

In order to discuss the simulation model of the ship transmission line and the state of the transmission line, an early fault model is built according to the evolution principle of the short circuit fault of the transmission line and combining with the fault characteristics of the early fault. A small distributed ship transmission line system is built in MATLAB/ Simulink. Then, combined with the constructed fault module, the original short circuit module, and the load module, the various states (normal state, early fault state, severe early fault state, short circuit state) of the ship transmission line are stimulated, and the features of voltage signal in each state is analysed. It is concluded that, due to the normal operation of the ship transmission line system, the variation characteristics of the flow signal and voltage signal caused by the sudden load mutation, that is, the sudden load and the sudden increase load, are very similar to the changes caused by the early fault. Therefore, in order to find a more accurate early fault detection method, the state is divided into normal state, sudden load state, sudden increase and sudden decrease load state.

Open access

Zhiguo Li, Hongling Yang, Pingping Li, Jizhan Liu, Jizhang Wang and Yunfeng Xu

Abstract

Fruit biomechanics is needed for quality determination, multiscale modelling and engineering design of fruit processes and equipments. However, these determined fruit biomechanics data often have obvious differences for the same fruit or tissue. In order to investigate it, the fruit biomechanics based on anatomy was reviewed in this paper. First, the anatomical characteristics of fruit biomaterials were described at the macroscopic ‘tissue’ level and microscopic ‘cellular’ level. Subsequently, the factors affecting fruit biomechanics based on anatomy and the relationships between fruit biomechanics, texture and mechanical damage were summarised according to the published literature. Fruit biomechanics is mainly affected by size, number and arrangement of cells, quantity and volume of intracellular spaces, structure, thickness, chemical composition and permeability of cell walls, and pectin degradation level and turgor pressure within cells based on microanatomy. Four test methods and partial determined results of fruit biomechanics were listed and reviewed. The determined mechanical properties data of fruit are only approximate values by using the existing four test methods, owing to the fruit biomaterials being non-homogeneous and living. Lastly, further aspects for research on fruit biomechanics were proposed for the future.

Open access

Liu Yanpei, Li Chunlin, Yang Zhiyong, Chen Yuxuan and Xu Lijun

Abstract

This paper proposes a special System Architecture for Multi-tenancy SaaS Service (SAMSS), which studies the performance security issues at the business logic layer and data processing layer respectively. The Kalman filtering Admission Control algorithm (KAC) and the Greedy Copy Management algorithm (GCM) are proposed. At the business logic layer, Kalman filtering admission control algorithm is presented. It uses a Kalman filter to conduct the dynamic evaluation for the CPU resource for multi-tenancy SaaS service and reduces the unnecessary performance expenses caused by direct measurement of CPU resources. At the data processing layer, the Greedy Copy Management algorithm (GCM) is presented. It changes the copy placement as a K-partitioning set partitioning problem and adopts a greedy strategy to reduce the number of times for creating a data copy. Finally, the experimental analysis and results prove the feasibility and efficiency of the algorithms proposed.

Open access

Haoju Wang, Li Ni, Hongjun Yang, Limin Xu, Ning Ma and Honglei Ding

Abstract

In order to evaluate the prevalence of the Mycoplasma mycoides cluster in goats in Chongqing, China, an epidemiological survey in this area was carried out. A total of 68 samples were subjected to bacteria isolation on Hartley’s medium. Four isolates (three from lung tissue and one from nasal discharges) were recovered from the samples and identified as the Mycoplasma species by their morphological and biochemical characteristics. They were further confirmed by PCR using 16S rRNA specific primer pairs and by restriction enzyme analysis. In vitro antimicrobial susceptibility of the isolates indicated that some strains had developed resistance to the antibiotics tested. This is the first report on the isolation, identification, and molecular characterisation of Mycoplasma species isolated from goats in Chongqing. This study also revealed a prevalence of Mycoplasma species infection in goats in this area.

Open access

X. Yang, C. Liu, Y. Liu, X. Li and Y. Xu

Abstract

TiO2-SiO2 (TiO2 supported on SiO2) photocatalysts were prepared using an ultrasonic-assisted sol-gel method. These photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and photoluminescence spectra (PL). Their photocatalytic activities were investigated by the method of methyl orange oxidation. It was found that the photocatalytic activity of TiO2-SiO2 was optimal when the molar ratio of hexadecyl trimethyl ammonium bromide to titanium butoxide was 1:10. The average crystallite size of TiO2-SiO2 was smaller than that prepared by the stirring method. Furthermore, for pure anatase phase samples, it was shown that the lower the photoluminescence intensity, the higher the photocatalytic activity.

Open access

Ren-feng Li, Xiang-qin Tian, Yong Liu, Jing Xu and Dong-yang Liu

Abstract

Porcine epidemic diarrhea virus (PEDV) is having a severe effect on the pig breeding industry in central China. The mucosa and the content of the small intestine from newborn pre-weaned piglets with diarrhea were tested for the presence of PEDV by molecular and morphologic methods, and found to be positive. Negative-staining electron microscopy (EM) revealed the presence of coronavirus- like particles in the samples. The result of molecular detection by nested RT-PCR based on the amplification of the M gene was positive. Using a novel alternative method we successfully propagated the PEDV strain (CH/QX-2) in Vero cells, confirmed by ultrathin sections of the cells and Immunofluorescence assay (IFA). Phylogenetic analysis based on the partial S gene showed that the CH/QX-2 isolate was genetically closer to strains more commonly found in China, but differed genetically from two domestic strains (CH/S, 1986 and LZC, 2007), Korean strains (DR13, 2007), and the vaccine strain (CV777 vs) currently being used in China. CH/QX-2 formed a unique clade in the derived phylogenetic tree indicating that the CH/QX-2 strain currently circulating in central China is a new variant of PEDV. This study extends current knowledge on the diversity and epidemiology of PEDV.

Open access

Sirui Yang, Weihong Xu, Shibo Li, Shicheng Liu, Honghua Lu, Xiaosheng Hao, Feiyong Jia and Guiling Xue

Abstract

Background: Hereditary ataxia is a group of hereditary diseases that are characterized by chronic progressive uncoordinated gait and are frequently associated with cerebellar atrophy.

Objectives: To investigate evidence-based diagnosis of hereditary ataxia by retrospective analysis of the diagnostic process in one Chinese family.

Methods: Clinical records of 15 ataxia patients from one Chinese family with 46 family members were retrospectively reviewed and a tentative diagnosis was made based on clinical manifestations, signs and symptoms, mode of inheritance, and progression. Since hereditary ataxia is a group of heterogeneous diseases having various subtypes and overlapping symptoms, we adopted a stepwise evaluation to achieve a tentative diagnosis. To confirm the diagnosis, we performed polymerase chain reaction (PCR) specific for the suspected causative gene of spinocerebellar ataxia (SCA) subtype 3 (SCA3).

Results: Through analysis of hereditary and clinical characteristics of family histories of the patients, we suspected that the family might suffer from SCA, especially, SCA3. The PCR assay for SCA3 showed that, five of the ten samples analyzed had a CAG trinucleotide expansion of the SCA3 gene, and four of the five members developed ataxia. The remaining one, a seven-year-old girl, showed no symptoms or signs except for uvula deviation. No clinical symptoms were found in five other members with negative PCR results. Thus, based on both clinical findings and laboratory results, we further confirmed that the family suffered from SCA3.

Conclusion: Hereditary ataxias are disorders sharing overlapping symptoms. Comprehensive analysis of medical and family records together with genetic diagnosis improves diagnostic efficiency of hereditary ataxia and aides in family counseling.

Open access

Shijun Wu, Jianmin Xu, Guangyou Li, Zhaohua Lu, Chao Han, Yang Hu and Xinxian Hu

Abstract

Growth traits, wood properties, stem-branch characteristics and bark percentage were assessed for 60 Eucalyptus urophylla S.T. Blake clones in southern China measured at age 21, 52, 71 and 96 months. Analysis of variance showed that there were significant differences on growth traits, wood properties and individual tree wood weight among clones. Coefficients of genotypic variation ranged from 12.12% to 53.16% for growth traits, 9.02% to 20.18% for wood properties, 21.75% to 22.71% for stem-branch characteristics, 28.31% for bark percentage and 51.20% for individual tree wood weight. Repeatability ranged from 0.36 to 0.53 for growth traits, 0.35 to 0.51 for wood properties, 0.21 to 0.24 for stembranch characteristics, 0.07 for bark percentage and 0.31 for individual tree wood weight. The strongly negative genotypic correlations suggesting that selection on growth traits at 21 months can not be effective to predict growth traits at 96 months whereas it could be used to predict growth traits at 52 and 71 months. The genotypic correlations between growth traits and basic density were ranged from -0.78 to 0.28 and weakly positive phenotypic correlations were found between growth traits and basic density, ranging from 0.03 to 0.09. The selection gain on diameter at breast height over bark by different selection proportions at 21, 52, 71 and 96 months old expressed that selection gain at 71 months was some what higher than that at other ages during 10% to 30% selection proportion, while selection gain at 52 months was some what higher than that at other ages during 60% to 90% selection proportion. Wood properties and individual tree wood weight which are strongly related to end production and economically important in pulp production should be studied extensively especially for pulp breeding.