S1240系统话务台(DOP)全阻故障的处理

针对专用通信工作中,DOP话务台的作用越来越重要,现将本人在多年的维护工作中遇到的有关S1240程控交换机中DOP话务台出现全阻故障时的处理步骤分析如下,希望能给大维护人员提供些参考。

一次模块局全阻障碍的分析

本文分析了一个不能直接通过告警信息定位的“隐性障碍”实例,提出了处理类似问题应注意的几个方面的建议。

常温与低温灌注下狗全肝血流阻断比较实验

为了探讨全肝血流阻断带来的生理生化改变,常温下全肝血流阻断的安全时限及低温灌注下对肝脏的保护作用,作者采用脾颈静脉分流减压门静脉系统方法,将21只狗随机分为3组:A组全肝血流阻断45分钟;B组1小时;C组在低温灌注下全肝血流阻断1小时,观察动物一般情况,生理生化及病理学改变和术后生存率。结果表明,常温下狗全肝血流阻断安全时限为45分钟;超过1小时,动物发生休克,生理、生化、病理改变显著,术后存活率仅28.5％;低温灌注可起到明显的对肝脏缺血的保护作用。

电力电缆的阻水技术

主要介绍了阻水电力电缆在国内外的应用背景及产品具体分类,结合多年的产品研发和生产实际,对当前电力电缆阻水的一些最新技术和应用效果进行研究和分析,并重点介绍了结构阻水电力电缆的结构设计及应用效果。

城域光缆线路障碍查修方法

本文对城域光缆线路的全阻障碍、系统障碍及隐含的断纤障碍查修问题进行了详细的讨论,强调在 具体的障碍查修过程中,应把技术手段和实践经验结合起来,灵活应用。

How can portal vein cavernous transformation cause chronic incomplete biliary obstruction?

Biliary disease in the setting of non-cirrhotic portal vein thrombosis(and similarly in portal vein cavernous transformation) can become a serious problem during the evolution of disease.This is mostly due to portal biliary ductopathy.There are several mechanisms that play a role in the development of portal biliary ductopathy,such as induction of fibrosis in the biliary tract(due to direct action of dilated peribiliary collaterals and/or recurrent cholangitis),loss of biliary motility,chronic cholestasis(due to fibrosis or choledocholithiasis) and increased formation of cholelithiasis(due to various factors).The management of cholelithiasis in cases with portal vein cavernous transformation merits special attention.Because of a heterogeneous clinical presentation and concomitant pathophysiological changes that take place in biliary anatomy,diagnosis and therapy can become very complicated.Due to increased incidence and complications of cholelithiasis,standard treatment modalities like sphincterotomy or balloon sweeping of bile ducts can cause serious problems.Cholangitis,biliary strictures and hemobilia are the most common complications that occur during management of these patients.In this review,we specifically discuss important issues about bile stones related to bile duct obstruction in non-cirrhotic portal vein thrombosis and present evidence in the current literature.

Acoustic design sensitivity analysis of structural sound radiation

This paper presents an acoustic design sensitivity(ADS)analysis on sound radiation of structures by using the boundary element method(BEM).We calculated the velocity distribution of the thin plate by analytical method and the surface sound pressure by Rayleigh integral,and expressed the sound radiation power of the structure in a positive definite quadratic form of the Hermitian with an impedance matrix.The ADS analysis of the plate was thus translated into the analysis of structure dynamic sensitivity and ...

CLINICAL SIGNIFICANCE OF COMPLETE LEFT BUNDLE BRANCH BLOCK IN DILATED CARDIOMYOPATHY

Clinical, electrocardiographic and echocardiographic findings in 64 patients with dilated cardiomyopathy were retrospectively studied. Compared with 51 patients without complete left bundle branch block (CLBBB), 13 patients with CLBBB had higher New York Heart Association (NYHA) functional class (P<0. 05), increased left ventricular end-diastolic and end-systolic diameters (P<0. 002) and myocardial mass (P<0. 02). severe mitral regurgitation (P<0. 01) and higher mortality rate (P<0. 04). Multivariate stepwise regression analysis revealed that the presence of CLBBB was an independent prognostic factor for patients with dilated cardiomyopathy.

Method of branch ariflow for calculatinga complicated mine ventilation networks

The solutions widely used at present for calculating complicated mine ventilation networks are ones in which resistance of the branches and characteristic parameters of the fans are taken as basic input data. But it is time and energy consuming to obtain the branch resistance values. A new solution is developed in this paper in which the branch resistance values are obtained through measuring and evaluating the airflow of the whole ventilation network. Theoretical analysis is made of the establishment of a linear equation series with branch resistance as unknown numbers, an equation series for which one, and only one, result of solutions exists. This solution is programmed in C language and passed on a personal computer. The programmed solution programmed proves of practical use, as demonstrated by specific examples. Being different from other solutions, the method takes the branch airflow and fan working points as basic input data, and the present solution is of greater advantage for calculating ventilation networks of mines in operation.

Pseudo-Magnetotelluric 2D Inversion Technology of Magnetic-Source Transient Electromagnetics

Based on the fact that it is diffi cult to implement optimum inversion using 2D and 3D forward modeling with magnetic-source transient electromagnetics(TEM),this paper explores a novel approach to the implementation of 2D magnetic-source TEM inversion.In particular,we converted magnetic-source TEM data into magnetotelluric(MT)data and then used a 2D MT inversion method to implement a 2D magnetic-source TEM inversion interpretation.First,we studied the similarity between magnetic-source TEM waves and MT waves and between magnetic-source TEM all-time apparent resistivity and MT Cagniard apparent resistivity.Then,we selected an optimal time-frequency transformation coeffi cient to implement rapid time-frequency transformation of all-time TEM apparent resistivity to MT Cagniard apparent resistivity.Afterward,we conducted 1D pseudo-MT inversions of magnetic-source 1D TEM theoretical models.The 1D inversion results demonstrated that the diff erence between the inversion parameters and model parameters was small,while the MT 1D inversion method could be used to conduct magnetic 1D TEM inversion within a certain margin of error.We further conducted 2D pseudo-MT inversions of 3D magnetic-source TEM theoretical models,and the 2D inversion results indicated that selecting a joint 2D pseudo-MT transverse-electric(TE)and transverse-magnetic(TM)inversion method based on measuring the line above a 3D anomalous body can help to accurately implement a 2D inversion interpretation of the 3D TEM response.

Gravitational search algorithm for coordinated design of PSS and TCSC as damping controller

A newly developed heuristic global optimization algorithm, called gravitational search algorithm （GSA）, was introduced and applied for simultaneously coordinated designing of power system stabilizer （PSS） and thyristor controlled series capacitor （TCSC） as a damping controller in the multi-machine power system. The coordinated design problem of PSS and TCSC controllers over a wide range of loading conditions is formulated as a multi-objective optimization problem which is the aggregation of two objectives related to damping ratio and damping factor. By minimizing the objective function with oscillation, the characteristics between areas are contained and hence the interactions among the PSS and TCSC controller under transient conditions are modified. For evaluation of effectiveness and robustness of proposed controllers, the performance was tested on a weakly connected power system subjected to different disturbances, loading conditions and system parameter variations. The cigenvalues analysis and nonlinear simulation results demonstrate the high performance of proposed controllers which is able to provide efficient damping of low frequency oscillations.

Investigation and prediction of enteral nutrition problems after percutaneous endoscopic gastrostomy

AIM： To investigate and predict enteral nutrition problems after percutaneous endoscopic gastrostomy （PEG）. METHODS： We retrospectively analyzed data for 252 out of 285 patients who underwent PEG at our hospital from 1999 to 2008 after PEG were defined as： Enteral nutrition problems （1） patients who required ≥ 1 mo after surgery to switch to complete enteral nutrition, or who required additional parenteral alimentation continuously; or （2） patients who abandoned switching to enteral nutrition using the gastrostoma and employed other nutritional methods. We attempted to identify the predictors of problem cases by using a logistic regression analysis that examined the patients＇ backgrounds and the specific causes that led to their problems. RESULTS： Mean age of the patients was 75 years, and in general, their body weight was low and their overall condition was markedly poor. Blood testing revealed that patients tended to be anemic and malnourished. A total of 44 patients （17.5%） were diagnosed as having enteral nutrition problems after PEG. Major causes of the problems included pneumonia, acute enterocolitis （often Clostridium difficile-related）, paralytic ileus and biliary tract infection. A multivariate analysis identified the following independent predictors for problem cases： （1） enteral nutrition before gastrectomy （a risk reduction factor）; （2） presence of esophageal hiatal hernia; （3） past history of paralytic ileus; and （4） presence of chronic renal dysfunction. CONCLUSION： Enteral nutrition problems after PEG occurred at a comparatively high rate. Patient background analysis elucidated four predictive factors for the problem cases.

Application of obturator to treat velopharyngeal incompetence

OBJECTIVE: To evaluate the effect of a system of velopharyngeal incompetence (VPI) management after the application of obturator. METHODS: Using nasopharyngofiberoscope (NPF) and a computer analysis system, we quantitatively analyzed the improved state of velopharyngeal incompetence in 100 patients with unilateral and/or bilateral cleft palate. RESULTS: The velopharyngeal closure (VPC) can be greatly improved by using a temporary oral prosthesis (obturator) and speech training. An objective quantitative standard was established to evaluate the change of velopharyngeal closure of cleft palate patients after surgery and conservative treatment. CONCLUSIONS: The method used is more succinct, accurate and practical than previous methods. In order to reflect the state of velopharyngeal incompetence, the concept of improvement rate of velopharyngeal incompetence (IRVPI) is put forward.

Identification of the novel recessive gene pi55(t) conferring resistance to Magnaporthe oryzae

The elite rice cultivar Yuejingsimiao 2 （YJ2） is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance （R） gene donor culti- vats such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F2 and F4 populations indicated the re- sistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a hulked-segregant analysis using genome-wide selected SSR markers with F4 lines that segregated into 3 resistant （R）： 1 susceptible （S） or 1R：3S. The recessive R gene on chromosome 8 was further mapped to an interval ~1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F4 line that segregated into 1R：3S. Given that no major R gene was mapped to this inter- val, the novel R gene was designated as pi55（t）. Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metalassociated domain-containing protein, respectively, were suggested as the most likely candidates for pi55（t）.

Recent advances in all-in-one flexible supercapacitors

The rise of personalized flexible electronics has promoted the rapid development of flexible supercapacitors due to their long service life,fast charging-discharging rates and safe operation.Different from the traditional flexible supercapacitors,the all-in-one integrated flexible supercapacitors are more resistant to deformation and lower interface resistance,which have a broader application prospect in the field of flexible electronics.This review briefly summarizes the preparation methods and electrochemical properties of some typical all-in-one supercapacitors,represented by planar and fibrous structures in recent years.Firstly,the basic understanding of traditional flexible supercapacitors and all-in-one integrated flexible supercapacitors,and the key parameters of the performance of flexible supercapacitors are introduced.Subsequently,the hydrogel matrix all-in-one supercapacitors with different functional characteristics(stretchable,self-healing and compressible)and the nonhydrogel matrix(separator,flexible membrane)all-in-one supercapacitors are discussed.Furthermore,the challenges and future development of flexible supercapacitors are considered.

Effects of mass layer imperfect bonding on the electrical impedance of a quartz crystal microbalance

We study electrically forced vibrations of a crystal plate of AT-cut quartz carrying a thin mass layer operating as a quartz crystal microbalance for mass sensing.The mass layer is imperfectly bonded to the crystal plate with their interface described by the so-called interface-slip model which allows a discontinuity of the tangential interface displacement.Mindlin’s equations for piezoelectric plates are used.An analytical solution is obtained.The electrical impedance is calculated.The effects of an elastic interface and a viscoelastic interface are examined.

A TOP6BL mutation abolishes meiotic DNA double-strand break formation and causes human infertility

Meiosis is pivotal for sexual reproduction and fertility. Meiotic programmed DNA double-strand breaks(DSBs) initiate homologous recombination, ensuring faithful chromosome segregation and generation of gametes. However, few studies have focused on meiotic DSB formation in human reproduction.Here, we report four infertile siblings born to a consanguineous marriage, with three brothers suffering from non-obstructive azoospermia and one sister suffering from unexplained infertility with normal menstrual cycles and normal ovary sizes with follicular activity. An autosomal recessive mutation in TOP6BL was found co-segregating with infertility in this family. Investigation of one male patient revealed failure in programmed meiotic DSB formation and meiotic arrest prior to pachytene stage of prophase I.Mouse models carrying similar mutations to that in patients recapitulated the spermatogenic abnormalities of the patient. Pathogenicity of the mutation in the female patient was supported by observations in mice that meiotic programmed DSBs failed to form in mutant oocytes and oocyte maturation failure due to absence of meiotic recombination. Our study thus illustrates the phenotypical characteristics and the genotype-phenotype correlations of meiotic DSB formation failure in humans.