Optical and mechanical response of high temperature optical fiber sensors

The National Aerospace Plane (NASP) will experience temperatures as high as 2500 F at critical locations in its structure. Optical fiber sensors were proposed as a means of monitoring the temperature in these critical regions by either bonding the optical fiber to, or embedding the optical fiber in, metal matrix composite (MMC) components. Unfortunately, the anticipated NASP temperature ranges exceed the glass transition region of the optical fiber glass. The attempt is made to define the operating temperature range of optical fiber sensors from both optical and mechanical perspectives. A full non-linear optical analysis was performed by modeling the optical response of an isolated sensor cyclically driven through the glass transition region

La globalización, un proceso científico y tecnológico que genera irreversibles cambios sociales

La globalización es un término en boga que se utiliza para explicar el reciente acercamiento económico y social producido entre los habitantes de naciones distantes. A pesar que la palabra fue acuñada hace unas décadas atrás, este concepto es antiguo. Los países a lo largo de diferentes períodos de la historia estuvieron más cerca o más distantes. Imperios con sistemas de gobierno unificado concibieron lazos entre culturas lejanas que se disolvieron junto a la caída de los mismos. Convenios comerciales y políticos dieron lugar a la influencia de culturas dominantes sobre otras en distintos momentos históricos. Sin embargo todos ellos fueron y serán reversibles ya que con la ruptura de los acuerdos las distancias volvieron a aparecer. No obstante la ciencia y la avidez del hombre por conocer las causas de la naturaleza dieron lugar a desarrollos tecnológicos que desde sus orígenes acercaron a las personas de lugares distantes. Las invenciones nunca retrocedieron, siempre avanzaron hacia la concepción de un mundo más cercano dando lugar a cambios sociales que modificaron definitivamente el estilo de vida de los habitantes del mundo. Este trabajo busca analizar a la globalización desde una mirada diferente a la políticaeconómica. La intención es profundizar el concepto como un proceso continuo de interconexión de las sociedades, con períodos de mayor y menor aceleración, que surgen del progreso de la ciencia y la tecnología.globalización, cambios sociales, hábitos, sociedad, desarrollo tecnológico, ciencia, tecnología.

Measurement of distributed strain and temperature based on higher order and higher mode Bragg conditions

A Bragg grating sensor for measuring distributed strain and temperature at the same time comprises an optical fiber having a single mode operating wavelength region and below a cutoff wavelength of the fiber having a multimode operating wavelength region. A saturated, higher order Bragg grating having first and second order Bragg conditions is fabricated in the optical fiber. The first order of Bragg resonance wavelength of the Bragg grating is within the single mode operating wavelength region of the optical fiber and the second order of Bragg resonance wavelength is below the cutoff wavelength of the fiber within the multimode operating wavelength region. The reflectivities of the saturated Bragg grating at the first and second order Bragg conditions are less than two orders of magnitude of one another. In use, the first and second order Bragg conditions are simultaneously created in the sensor at the respective wavelengths and a signal from the sensor is demodulated with respect to each of the wavelengths corresponding to the first and second order Bragg conditions. Two Bragg conditions have different responsivities to strain and temperature, thus allowing two equations for axial strain and temperature to be found in terms of the measure shifts in the primary and second order Bragg wavelengths. This system of equations can be solved for strain and temperature

TMF is a golgin that binds Rab6 and influences Golgi morphology

BACKGROUND: Golgins are coiled-coil proteins associated with the Golgi apparatus, that are believed to be involved in the tethering of vesicles and the stacking of cisternae, as well as other functions such as cytoskeletal association. Many are peripheral membrane proteins recruited by GTPases. Several have been described in animal cells, and some in yeast, but the relationships between golgins from different species can be hard to define because although they share structural features, their sequences are not well conserved. RESULTS: We show here that the yeast protein Sgm1, previously shown to be recruited to the Golgi by the GTPase Ypt6, binds to Ypt6:GTP via a conserved 100-residue coiled-coil motif that can be identified in a wide range of eukaryotes. The mammalian equivalent of Sgm1 is TMF/ARA160, a protein previously identified in various screens as a putative transcription or chromatin remodelling factor. We show that it is a Golgi protein, and that it binds to the three known isoforms of the Ypt6 homologue Rab6. Depletion of the protein by RNA interference in rat NRK cells results in a modest dispersal of Golgi membranes around the cell, suggesting a role for TMF in the movement or adherence of Golgi stacks. CONCLUSION: We have identified TMF as an evolutionarily conserved golgin that binds Rab6 and contributes to Golgi organisation in animal cells

Multifocal Langerhans Cell Histiocytosis in an Adult

Eosinophilic granuloma (EG) is the most common and benign form of the spectrum of disorders referred to as Langerhans cell histiocytosis (LCH). Langerhans cell histiocytosis is primarily regarded as a pediatric disease, with few adult cases of multifocal EG of bone reported. We report a case of multifocal EG in a 48-year-old woman, who presented with right knee pain. Radiographs showed a small lytic lesion in the medial femoral condyle. Diagnosis was confirmed by ultrasound-guided biopsy. She had had a previous EG lesion excised from her skull. Whole-body bone scan demonstrated a new skull lesion in the right diploic space, which was confirmed by magnetic resonance imaging. The patient underwent curettage, bone grafting, and prophylactic internal fixation of the right distal femur lesion. The skull lesion was treated with repeat craniectomy. Two years later, she developed a new lesion in the right distal femoral metaphysis, which was treated with intralesional corticosteroid injections. Now, more than 1 year later, the patient is pain-free with no evidence of new or recurrent disease. Because multifocal EG is a rare diagnosis in adults, appropriate clinical suspicion, in combination with radiographic findings and histologic examination, is essential for correct diagnosis and treatment

Position and motion estimation for visual robot control with planar targets

This paper addresses two problems in visually-controlled robots. The first consists of positioning the end-effector of a robot manipulator on a plane of interest by using a monocular vision system. The problem amounts to estimating the transformation between the coordinates of an image point and its three-dimensional location supposing that only the camera intrinsic parameters are known. The second problem consists of positioning the robot end-effector with respect to an object of interest free to move on a plane, and amounts to estimating the camera displacement in a stereo vision system in the presence of motion constraints. For these problems, some solutions are proposed through dedicated optimizations based on decoupling the effects of rotation and translation and based on an a-priori imposition of the degrees of freedom of the system. These solutions are illustrated via simulations and experiments. ©2009 ACA.published_or_final_versionThe 7th Asian Control Conference (ASCC 2009), Hong Kong, China, 27-29 August 2009. In Proceedings of the Asian Control Conference, 2009, p. 372-37

ASU Formula Lightning Race Vehicle Report Prepared for Ohio Aerospace Institute

This report describes the drive system in the Arizona State University Formula Lightning electric race car when it participated in the 1994 Cleveland Electric Formula Classic on 9 July 1994. In addition, the telemetry system used to monitor the car's performance and plans for improving the car's performance are described

Market segmentation in urban tourism: a study in Latin America

This study aims to analyze the different segments of urban tourism demand. The data were collected in Mexico City, Lima, Buenos Aires, and Bogota, and a K-means clustering method was used to find the segments. The results showed three segments: the first cluster grouped tourists interested in enjoying lodging and restaurant services; the second included visitors seeking multiple attractions, who were the most willing to recommend the destinations; finally, the third was composed of passive tourists, not drawn to the attractions of these cities. This study contributes to the literature by offering evidence of urban tourism segmentation in Latin American cities, which has been scarcely researched. Furthermore, it sheds light on this topic by finding a segment not previously described in the literature ("multiple attractions"). Finally, this study offers practical implications for managers of tourism companies to plan and improve the competitiveness of destinations based on the different segments found

Urban turism perception and recommendation in Mexico City and Lima

Mexico City and Lima both have great cultural and historical value as they developed close to major pre-Columbian civilizations. When comparing their urban attractiveness factors, they present differences and similarities that need to be understood at a theoretical level. The study has practical implications as tourism officials and managers in each of these two cities can draw inspiration from the best practices of the other city. The method is quantitative, and the exploratory factorial analysis technique was used to reduce the variables in a group of factors. The results indicate that the different aspects of the cities? tourism attractiveness can be categorized into four factors: the nucleus, the tourist ecosystem, MICE & shows, and related services. A comparison of the two cities? Kruskal?Wallis test scores shows significant differences in terms of three variables: monuments and historic sites, museums and art galleries, and shops and commercial services