Efficient numerical method for various geometries of gas lubricated bearings

This paper discusses the development of a numerical solver for the Reynolds equation in aerodynamic lubricated bearings, utilizing a finite difference method with multigrid. The advantages of the numerical method are that the number of operations and the memory capacity needed are almost proportional to the number of gridpoints involved. It is second order accurate and can cope with various bearing geometries. A survey is also given of the implemented modifications of the Reynolds equation. The efficiency of the method is demonstrated by two examples, namely: the dynamic tracking of the centre of a herringbone grooved journal bearing and the equilibrium position of a hard disk slider

Перспективы развития рынка огнеупоров для сталеплавильного комплекса Украины

Основной эффект в снижении удельного расхода огнеупоров достигается за счет создания новых видов огнеупорных материалов, технологических усовершенствований при их производстве, развития новых конструкционных схем футеровки технологических агрегатов, совершенствования условий эксплуатации и ремонта футеровки и т. п. На металлургических предприятиях Украины в этом плане в последние годы наблюдается достаточно устойчивая тенденция повышения стойкости футеровки конвертеров, дуговых сталеплавильных печей, сталеразливочных и промежуточных ковшей.Основний ефект у зниженні питомої витрати вогнетривів досягається за рахунок створення нових видів вогнетривких матеріалів, технологічних удосконалень при їх виробництві, розвитку нових конструкційних схем футерівки технологічних агрегатів, удосконалення умов експлуатації та ремонту футерівки тощо. На металургійних підприємствах України в цьому плані в останні роки спостерігається досить стійка тенденція підвищення стійкості футерівки конвертерів, дуго- вих сталеплавильних печей, сталерозливних і проміжних ковшів.The main effect in reducing the specific consumption of refractories is reached by the creation of new types of refractory materials, technological improvements in their production, development of new structural patterns lining process units, improved operating conditions and lining repair, etc. In this regard, at Ukrainian metallurgical enterprises in recent years there has been quite stable tendency to increase the resistance of lining converters, electric arc steel furnaces, steel-teeming and tundish ladles

Intraluminale stents voor de behandeling van tracheacollaps bij de hond

Tracheal collapse is a progressive degenerative disease that can be symptomatically treated with medication and/or by surgical intervention This article reports 5 cases with serious dyspnea, exercise intolerance, syncope or cyanosis caused by tracheal collapse All clogs showed a poor quality of life despite medical treatment Enlargement of the tracheal lumen was achieved by the placement of an intraluminal prosthesis to support the collapsing trachea Observed complications after the placement of an intraluminal stent were attributed to inappropriately sized stents (development of granulation tissue, shortening with undersized diameter and recurrence when the trachea is only partly supported). Complications caused by intraluminal stems can be life threatening One patient died of tracheal obstruction by granulation tissue. The life quality of the other 4 patients improved considerably. 2 patients improved (mean follow-up 3 5 months) and 2 patients became asymptomatic (mean follow-up 9 months)

Post-epizootic salamander persistence in a disease-free refugium suggests poor dispersal ability of Batrachochytrium salamandrivorans

Lack of disease spill-over between adjacent populations has been associated with habitat fragmentation and the absence of population connectivity. We here present a case which describes the absence of the spill-over of the chytrid fungus Batrachochytrium salamandrivorans (Bsal) between two connected subpopulations of fire salamanders (Salamandra salamandra). Based on neutrally evolving microsatellite loci, both subpopulations were shown to form a single genetic cluster, suggesting a shared origin and/or recent gene flow. Alpine newts (Ichthyosaura alpestris) and fire salamanders were found in the landscape matrix between the two sites, which are also connected by a stream and separated by no obvious physical barriers. Performing a laboratory trial using alpine newts, we confirmed that Bsal is unable to disperse autonomously. Vector-mediated dispersal may have been impeded by a combination of sub-optimal connectivity, limited dispersal ability of infected hosts and a lack of suitable dispersers following the rapid, Bsal-driven collapse of susceptible hosts at the source site. Although the exact cause remains unclear, the aggregate evidence suggests that Bsal may be a poorer disperser than previously hypothesized. The lack of Bsal dispersal between neighbouring salamander populations opens perspectives for disease management and stresses the necessity of implementing biosecurity measures preventing human-mediated spread

A novel time series approach to bridge coding changes with a consistent solution across causes of death

Revisions of the International Classification of Diseases (ICD) can lead to biases in cause-specific mortality levels and trends. We propose a novel time series approach to bridge ICD coding changes which provides a consistent solution across causes of death. Using a state space model with interventions, we performed time series analysis to cause-proportional mortality for ICD9 and ICD10 in the Netherlands (1979–2010), Canada (1979–2007) and Italy (1990–2007) on chapter level. A constraint was used to keep the sum of cause-specific interventions zero. Comparability ratios (CRs) were estimated and compared to existing bridge coding CRs for Italy and Canada. A significant ICD9 to ICD10 transition occurred among 13 cause of death groups in Italy, 7 in Canada and 3 in the Netherlands. Without the constraint, all-cause mortality after the classification change would be overestimated by 0.4 % (NL), 0.03 % (Canada) and 0.2 %(Italy).ThetimeseriesCRswereinthesamedirectionasthebridgecodingCRsbut deviated more from 1. A smooth corrected trend over the ICD-transition resulted from applying the time series approach. Comparing the time series CRs for Italy (2003), Canada (1999) and the Netherlands (1995) revealed interesting commonalities and dif- ferences. We demonstrated the importance of adding the constraint, the validity of our methodology and its advantages above earlier methods. Applying the method to more specific causes of death and integrating medical content to a larger extent is advocated

A Novel Time Series Approach to Bridge Coding Changes with a Consistent Solution Across Causes of Death

Revisions of the International Classification of Diseases (ICD) can lead to biases in cause-specific mortality levels and trends. We propose a novel time series approach to bridge ICD coding changes which provides a consistent solution across causes of death. Using a state space model with interventions, we performed time series analysis to cause-proportional mortality for ICD9 and ICD10 in the Netherlands (1979–2010), Canada (1979–2007) and Italy (1990–2007) on chapter level. A constraint was used to keep the sum of cause-specific interventions zero. Comparability ratios (CRs) were estimated and compared to existing bridge coding CRs for Italy and Canada. A significant ICD9 to ICD10 transition occurred among 13 cause of death groups in Italy, 7 in Canada and 3 in the Netherlands. Without the constraint, all-cause mortality after the classification change would be overestimated by 0.4 % (NL), 0.03 % (Canada) and 0.2 % (Italy). The time series CRs were in the same direction as the bridge coding CRs but deviated more from 1. A smooth corrected trend over the ICD-transition resulted from applying the time series approach. Comparing the time series CRs for Italy (2003), Canada (1999) and the Netherlands (1995) revealed interesting commonalities and differences. We demonstrated the importance of adding the constraint, the validity of our methodology and its advantages above earlier methods. Applying the method to more specific causes of death and integrating medical content to a larger extent is advocated