Structural health monitoring of a masonry viaduct with Fibre Bragg Grating sensors

The Marsh Lane viaduct is a masonry railway bridge constructed during the 19th century nearby Leeds Central Railway Station. The bridge appears significantly damaged due to the increase of the operational train loads over the last decades and due to environmental effects. Due to this degradation, extensive repair was conducted in 2015. After this repair work, an extensive fibre optic sensor network was installed below three spans of the bridge to monitor surface strains at 68 locations on the underside of the arch spans. The paper compares data collected from two monitoring periods, 16 months apart. Combining statistical analysis and signal processing techniques, the results show that local damage, as well as change in the global dynamic behaviour of the structure over time, can be effectively detected with the use of Fibre Bragg Grating sensors.This work is being funded by the Lloyd’s Register Foundation, EPSRC and Innovate UK through the Data-Centric Engineering programme of the Alan Turing Institute and through the Cambridge Centre for Smart Infrastructure and Construction (CSIC). Funding for the monitoring installation was provided by EPSRC under the Ref. EP/N021614/1 grant and by Innovate UK under the Ref. 920035 grant

Comunicación corta. Efecto del momento de la recolección sobre la producción y la calidad del forraje en genotipos de colza y nabo

The effects of two different harvest stages (full flowering and full podding) on forage yield and quality of ten forage rape (Brassica napus L. var. oleifera) and three turnip (Brassica rapa L. var. rapa) cultivars were evaluated under rainfed conditions in a Mediterranean type climate at Bursa, Turkey, during the 2002/2003 and 2003/2004 growing seasons. Plant height, branches per plant, leaf length and width, plant part components, and dry matter (DM) and crude protein (CP) yield were measured. Significant differences were observed for the main effects cultivar and harvest stage on DM and protein yields. The CP content of the whole plant and vegetative parts of the Brassica genotypes decreased as plant maturity progressed. In general, turnip cultivars showed better performance in DM yield. Fall sown turnip produced 9.10 and 12.1 Mg/ha DM yield, with 15.1 and 9.10% CP concentrations, at full flowering and at podding stage, respectively. Significant differences were noted among cultivars for these two parameters. Protein content decreased dramatically in stem parts when maturity advanced from full flower to full pod stages. High leaf percentage and high protein content at full flowering suggest that this should be the preferred forage harvest stage for rape and turnip cultivars.Se evaluaron los efectos de dos momentos diferentes de la recolección (en flor o vaina completada) sobre la producción y calidad del forraje en 10 cultivares forrajeros de nabo (Brassica napus L. var. oleifera) y tres de colza (Brassica rapa L. var. rapa) en Bursa, Turquía, una zona de clima mediterráneo con precipitaciones, durante las campañas 2002/2003 y 2003/2004. Se midió la altura de las plantas, ramas por planta, longitud y anchura de hoja, componentes de partes de las plantas, y producción de materia seca (MS) y proteínas crudas (PC). Se observaros diferencias significativas para los principales efectos cultivar y momento de la recolección sobre el rendimiento en MS y PC. El contenido en PC de la planta completa y partes vegetativas de los genotipos de Brassica estudiados disminuyeron al avanzar la maduración de la planta. En general, los cultivares de nabo dieron mejor producción de MS. Nabos sembrados en otoño produjeron 9,10 y 12,1 Mg/ha de MS, con concentraciones de PC de 15,1 y 9,10%, en los momentos de flor o vaina completas, respectivamente. Para estos dos parámetros se observaron diferencias significativas entre cultivares. El contenido en proteínas disminuyó dramáticamente en partes del tallo cuando la planta pasó del estado de flor completa a vaina completa. La detección de un alto porcentaje de hojas y de contenido en proteínas en cultivares de colza y nabo en el estadío de flores completas sugieren que éste debe ser el momento preferido para la recolección

Airborne Pathogens Transport in an Aircraft Cabin

Airborne pathogens can spread within an aircraft cabin from sneezing, coughing or breathing of a sick passenger. This paper reports a 3D numerical study on the transport of airborne pathogens inside Boeing 767 cabin. After cough or sneeze of an infected passenger, the entire unsteady pathogen dispersion process is simulated. Effects under study include the direction of coughing on the pathogens propagation and the spreading times from infected to hosts passengers

A note on the (h,q)-Zeta type function with weight alpha

The objective of this paper is to derive symmetric property of (h,q)-Zeta function with weight alpha. By using this property, we give some interesting identities for (h,q)-Genocchi polynomials with weight alpha. As a result, our applications possess a number of interesting property which we state in this paper.Comment: 7 page

The Marsh Lane Railway Viaduct: 2 Years of Monitoring with Combined Sensing and Surveying Technologies

Marsh Lane viaduct is a typical example of a 19th century brick masonry railway arch in the UK. It frequently carries passenger trains to and from Leeds Station. This paper broadly discusses the sensing techniques and associated analysis procedures used to (i) identify the reasons for existing damage, (ii) quantify their impact on the dynamic response of the structure and (iii) measure degradation of the response over a period of one year. To identify existing damage, distortions in geometry of the structure are examined with new point cloud processing techniques. With the aid of limit analyses, these distortions are interpreted, and past support movements which may have caused the distortions are identified. Then, to measure the dynamic response of the bridge, quasi-distributed fibre optic strain sensing and digital image correlation displacement measurement techniques are used. These highlight the increased dynamic response around locations of existing damage, and point out to the global mechanisms of response that could propagate damage. Continuous fibre optic strain measurements between November 2017 and 2018 are then discussed to investigate the ongoing deterioration.This work is being funded by the Lloyd’s Register Foundation, EPSRC and Innovate UK through the Data-Centric Engineering programme of the Alan Turing Institute and through the Cambridge Centre for Smart Infrastructure and Construction. Funding for the monitoring installation was provided by EPSRC under the Ref. EP/N021614/1 grant and by Innovate UK under the Ref. 920035 grant

Mapping deformations and inferring movements of masonry arch bridges using point cloud data

Many historic masonry arch bridges experience damage due to support movements during their lifetime. This damage may influence the performance of the bridge and reduce its load carrying capacity. This paper proposes a new method to quantify past support movements by investigating distortions in bridge geometry. In this method, the bridge geometry is recorded in point cloud format and segmented into different structural components (e.g. 3D piers and barrels or 2D pier and barrel cross-sections). The geometry of each component is investigated further withby fitting primitive shapes (e.g. 3D planes and cylinders or 2D lines and arcs) which represent the design intent. The discrepancy between these fitted shapes and the point clouds reveals a characteristic distortion signature. This signature is compared with theoretical distortion traces, which are obtained from kinematical analyses of the arch subjected to a range of support movements. The most likely support movement scenarios identified from these comparisons are then validated with visual indications of damage, such as crack location and size, and other geometric quantities, such as the change of the bedding joint elevations along the bridge. The proposed technique is applied to two masonry rail viaducts in the UK, which demonstrate different evidence of damage. Using the proposed method, past support movements of both bridges, which led to the observed damage, are inferred

Developing a Measure of Safety Data Culture

Safety is a critical concern for many organizations, especially those in construction and manufacturing. A newer approach to improving an organization’s decision making involves the use of data analytics. In regard to safety, the use of data analytics would allow for detecting and tracking risk factors such as behaviors, environmental contingencies, production, procedures, and hazards that are associated with workplace injuries. However, many organizations do not have a culture involving the use and measurement of relevant variables on an ongoing basis. Accordingly, the purpose of the study is to develop a measure of safety culture with a specific emphasis on the extent to which data is being utilized for management of safety in an organization. This measure of safety culture and analytics will assist in determining the extent to which an organization is ready to utilize data analytics into their safety program

Biosorption of Cr(VI) by free and immobilized Pediastrum boryanum biomass: equilibrium, kinetic, and thermodynamic studies

15th International Symposium on Toxicity Assessment (ISTA) -- JUL 03-08, 2011 -- City Univ Hong Kong, Hong Kong, PEOPLES R CHINAWOS: 000306790200053PubMed ID: 22374187The biosorption of Cr(VI) from aqueous solution has been studied using free and immobilized Pediastrum boryanum cells in a batch system. The algal cells were immobilized in alginate and alginate-gelatin beads via entrapment, and their algal cell free counterparts were used as control systems during biosorption studies of Cr(VI). The changes in the functional groups of the biosorbents formulations were confirmed by Fourier transform infrared spectra. The effect of pH, equilibrium time, initial concentration of metal ions, and temperature on the biosorption of Cr(VI) ion was investigated. The maximum Cr(VI) biosorption capacities were found to be 17.3, 6.73, 14.0, 23.8, and 29.6 mg/g for the free algal cells, and alginate, alginate-gelatin, alginate-cells, and alginate-gelatin-cells at pH 2.0, which are corresponding to an initial Cr(VI) concentration of 400 mg/L. The biosorption of Cr(VI) on all the tested biosorbents (P. boryanum cells, alginate, alginate-gelatin, and alginate-cells, alginate-gelatin-cells) followed Langmuir adsorption isotherm model. The thermodynamic studies indicated that the biosorption process was spontaneous and endothermic in nature under studied conditions. For all the tested biosorbents, biosorption kinetic was best described by the pseudo-second-order model.PROCORE-France/Hong Kong Joint Res Scheme, Croucher Fdn, KC Wong Educ Fd