Experimental evidences in bearing diagnostics for traction system of high speed trains

Rolling element bearings are the most critical components in the traction system of high speed trains. Monitoring their integrity is a fundamental operation in order to avoid catastrophic failures and to implement effective condition based maintenance strategies. Generally, diagnostics of rolling element bearings is usually performed by analyzing vibration signals measured by accelerometers placed in the proximity of the bearing under investigation. Several papers have been published on this subject in the last two decades, mainly devoted to the development and assessment of signal processing techniques for diagnostics. The experimental validation of such techniques has been traditionally performed by means of laboratory tests on artificially damaged bearings, while their actual effectiveness in specific industrial applications, particularly in rail industry, remains scarcely investigated. This paper is aimed at filling this knowledge gap, by addressing the diagnostics of bearings taken from the service after a long term operation on the traction system of a high speed train. Moreover, in order to test the effectiveness of the diagnostic procedures in the environmental conditions peculiar to the rail application, a specific test-rig has been built, consisting of a complete full-scale train traction system, able to reproduce the effects of wheeltrack interaction and bogie-wheelset dynamics. The results of the experimental campaign show that suitable signal processing techniques are able to diagnose bearing failures even in this harsh and noisy application. Moreover, the most suitable location of the sensors on the traction system is proposed, in order to limit their number.

Cyclic plastic deformation characteristics of subgrade under moving train wheel load

Cyclic plastic deformation of subgrade and other engineered layers is generally not taken into account in the design of railway bridge transition zones, although the plastic deformation is the governing factor of frequent track deterioration. Actual stress behavior of fine grained subgrade/embankment layers under train traffic is, however, difficult to replicate using the conventional laboratory test apparatus and techniques. A new type of torsional simple shear apparatus, known as multi-ring shear apparatus, was therefore developed to evaluate the actual stress state and the corresponding cyclic plastic deformation characteristics of subgrade materials under moving wheel load conditions. Multi-ring shear test results has been validated using a theoretical model test results; the capability of the multi-ring shear apparatus for replicating the cyclic plastic deformation characteristics of subgrade under moving train wheel load conditions is thus established. This paper describes the effects of principal stress rotation (PSR) of the subgrade materials to the cyclic plastic deformation in a railroad and impacts of testing methods in evaluating the influence of principal stress rotation to the track deterioration of rail track.

Introducing a new limit states design concept to railway concrete sleepers: An Australian experience

Over 50 years, a large number of research and development projects with respect to the use of cementitious and concrete materials for manufacturing railway sleepers have been significantly progressed in Australia, Europe, and Japan (Wang, 1996; Murray and Cai, 1998; Wakui and Okuda, 1999; Esveld, 2001; Freudenstein and Haban, 2006; Remennikov and Kaewunruen, 2008). Traditional sleeper materials are timber, steel, and concrete. Cost-efficiency, superior durability, and improved track stability are the main factors toward significant adoption of concrete materials for railway sleepers. The sleepers in a track system, as shown in Figure 1, are subjected to harsh and aggressive external forces and natural environments across a distance. Many systemic problems and technical issues associated with concrete sleepers have been tackled over decades. These include pre-mature failures of sleepers, concrete cancer or ettringite, abrasion of railseats and soffits, impact damages by rail machinery, bond-slip damage, longitudinal and lateral instability of track system, dimensional instability of sleepers, nuisance noise and vibration, and so on (Pfeil, 1997; Gustavson, 2002; Kaewunruen and Remennikov, 2008a,b, 2013). These issues are, however, becoming an emerging risk for many countries (in North and South Americas, Asia, and the Middle East) that have recently installed large volumes of concrete sleepers in their railway networks (Federal Railroad Administration, 2013). As a result, it is vital to researchers and practitioners to critically review and learn from previous experience and lessons around the world.

Dietary elecrolytes and cyclosporine toxicity. Experimental studies in spontaneuosly hypertensive rats

Cyclosporine-A (CsA) is widely used after organ transplantation to prevent rejection and in the treatment of autoimmune diseases. Hypertension and nephrotoxicity are common side-effects of CsA. Studies in patients on the prevention of the side-effects of CsA are difficult to conduct because the patients often receive a combination of different drugs thus making study of the side-effects of a single drug impossible. A challenge in experimental studies has been the lack of an animal model in which the side-effects concomitantly occur. Epidemiological data show an association between sodium (Na) intake and blood pressure. There is also evidence on low dietary intake of magnesium (Mg) and potassium (K) and high blood pressure. Our study was designed to develop an experimental model to study the side-effects of CsA in spontaneously hypertensive rats (SHR). On high dietary sodium, CsA caused hypertension, left ventricular hypertrophy (LVH), narrowing of the coronary arteries, small myocardial infarctions, and proteinuria, reduced creatinine clearance and histopathological renal injury in SHR. Loss of Mg into the urine caused by CsA resulted in Mg depletion in the tissues. Renal excretion of dopamine was reduced and the renin-angiotensin-aldosterone system was activated. We investigated the effects of dietary Mg and/or K and the calcium antagonist drug, isradipine, on the prevention of CsA toxicity. Dietary supplementation of Mg alone or in combination with K prevented from the deleterious pathophysiological and histopathological changes in the kidneys and the heart. K alone had little effect. Isradipine protected better than Mg from LVH, but the combination of isradipine and Mg was the most effective. Isradipine did not, however, protect against Mg loss. In our animal model, the combination of high dietary Na and treatment with CsA accelerated the development of the cardiovascular and renal changes clinically known as the side-effects of CsA. Dietary supplementation of Mg and K and reduction of Na intake and the calcium antagonist drug isradipine prevent from the deleterious effects of CsA.

Albert Einstein walking with Chaim Weizmann on deck of the S.S. Rotterdam en route to the United States Portraits Groups; Men

Digital Image

Momma's arc 1930-1945

The memoirs were written in New York in 1999. Description of the childhood of Rosemarie Schink, the author's mother, in the rural area of Meuszelwitz, Thuringia, where her grandfather, Franz Harnish, was the station manager. Rosemarie Schink eloped to Amsterdam with the Dutch Jew Judah Easel in 1931. The marriage fall apart soon thereafter, and Rosemarie was taken under the wings of her father-in-law Joseph Easel. The couple stayed officially married until their divorce in 1940, and Rosemarie worked in the pension of her in-laws. She had a long affair with the German Jew Guy Weinberg from Hamburg, a married man who was living in Amsterdam and became the father of her daughter Julia. Description of the Weinberg family history. In 1941 Rosemarie Schink married the Austrian Jewish lawyer Herbert Mauthner, the eldest of three sons of Robert Mauthner, director of the Bodenbacher-Dux Railroad and Melanie Leitner, daughter of a wealthy family from Veszprem, Hungary. Mauthner family history and nobility of the Leitner family, who were admitted to the court of the Austrian Kaiser Franz Joseph.

Israel Railways Commemorative Medal

Obverse: Israel Railroad emblem and a stretch of rail, inscription. Reverse: On the left, old steam engine; on the right, modern engine.

Temple Emanuel (Andover, Mass.) records, 1939-2001; and Part II (addendum), undated 1952-2004

Temple Emanuel was founded in 1920 in Lawrence, Massachusetts. It began by serving a small immigrant Jewish community that has since grown to an affluent and lively congregation of about 600 families. This growth occurred largely under the tenure of Rabbi Harry A. Roth, who lead the congregation from 1962 until 1990 and oversaw the temple’s move to Andover, Massachusetts. This collection includes correspondence, photographs, and sermons.

Judah P. Benjamin collection, undated, 1838-1942.

The collection consists of 25 letters written by Benjamin between 1838 and 1881 on a variety of subjects, four Confederate notes and two bonds bearing his picture, miscellaneous items about Benjamin (1893-1942), nine issues of the Congressional globe with speeches by Benjamin, as well as separate copies of his printed speeches, and a photostatic copy of the "Diary of Events" (400 pp.) kept by Benjamin, the original of which is in the Library of Congress (1862-1864).

Why Do Russians Support Censorship of the Media?

This article analyses support for censorship in Russia as part of the democratization process. Censorship has been an important part of Russian history and it was strengthened during the Soviet era. After the collapse of the Soviet system formal censorship was banned even though the reality has been different. Therefore it is not strange that many Russians would like to limit the freedom of the media and to censor certain topics. The views of Russians on censorship have been studied on the basis of a survey carried out in 2007. According to the results, three different dimensions of censorship were found. These dimensions include moral censorship, political censorship, and censorship of religious materials. Support for these dimensions varies on the basis of socio-demographic characteristics and media use. The article concludes that many Russians reject new phenomena, while support for the censorship of political criticism is not as high, but political censorship seems to enjoy more support among elites than among the common people.

Jätevesien puhdistuksen kustannuksista

English summary: Costs of purifying domestic sewage.

Escenas de la vida de Santo Domingo de Guzmán

Resumen: “Escenas de la Vida de Santo Domingo de Guzmán” es el título otorgado a la bella obra atribuida al pintor Pere Nicolau, uno de los máximos representantes del Gótico Internacional en Valencia. Esta obra nos informa de la imagen simbólica de Santo Domingo, creada a partir de la literatura hagiográfica y las manifestaciones artísticas en la Edad Media, “cada una en su lenguaje, su riqueza y sus límites, y en ellos reside su belleza, su capacidad de sugerir y de permitirnos soñar o recrearnos”.

Abordaje metodológico de la marginalidad urbana en el barrio San Francisquito de la ciudad de Rosario

Resumen: La ciudad de Rosario es la segunda área metropolitana del país que registra una incidencia relevante de asentamientos y población residente en los mismos. La mayoría de los asentamientos se ubica sobre viejos trazos de vías del ferrocarril, pero también los hay sobre las vías en uso y otros terrenos fiscales y privados. Los mismos ocupan el 2% de la superficie de la ciudad y el 15% de sus habitantes. Este estudio se realiza en el barrio San Francisquito, comprendido entre las calles Francia, Avellaneda, Ocampo y Seguí. El objetivo del mismo, es describir las estrategias metodológicas desarrolladas, durante este primer año, en el marco de la investigación. Los materiales y métodos utilizados están descriptos por etapas, en la primera se determinó la muestra de hogares, en la segunda se explica los ajustes al formulario de la encuesta de condiciones de vida y la tercera etapa desarrolla la estrategia de capacitación para el trabajo de campo. La muestra, distribuida por sector y radio; la adaptación de los formularios y los talleres de capacitación son los resultados alcanzados. Considerándose estratégico el fortalecimiento de las capacidades locales para la sustentabilidad del proyecto.

32m跨简支铁路桥梁横向振动的研究分析

基于频谱的概念,考虑列车行车的水平载荷的性质以及桥梁自振特性,通过理论分析以及实际的测试数据,得到32 m跨度的简支混凝土桥梁在行车时的振动情况,对结果进行了详细分析。提出32 m跨度桥梁的横向振动主要由桥墩的自振特性控制。最后,就避免铁路桥梁行车时的共振现象进行了初步分析,提出了可行的解决方案。