Fatalities in Trenching Operations—Analysis Using Models of Accident Causation

More than 65 construction workers are killed each year due to trench related accidents. Accident prevention begins with having a clear understanding of the causes of these accidents. This paper discusses the analysis of 296 fatality reports related to trenching operations from the Occupational Safety and Health Administration (OSHA) in the 1997–2001 time frame. In this paper, two models will be considered to analyze the fatality reports and to find the major relationships between the “how” and the “why” of trenching fatalities. The first model considers the causes related to physical processes, and the second model evaluates causes that can be linked to human behavior. The understanding of the major links between these two models and other factors will help to develop more effective strategies to prevent trenching fatalities.     

Combined Use of Local and Global Hydro Meteorological Data with Hydrological Models for Water Resources Management in the Magdalena - Cauca Macro Basin – Colombia

Water Resources Management - Reanalysis and earth observation data have enormous potential to support water resources management, particularly in river basins where data availability is poor or...     

Simulation As a Tool to Assess the Vulnerability of the Operation of a Health Care Facility

Health care systems are classified as critical infrastructure systems when responding to disaster events. Physical damage to health care facilities or disruption of their operations or supply chains could prevent an effective response and aggravate the outcome of an emergency situation. Even if a hospital or public health facility were not directly affected by the disaster event, these facilities are required to operate efficiently during an emergency in order to manage a surge of capacity. When infrastructure systems are damaged as a result of man-made or natural disaster events, insufficient supply of resources through these systems affects their performance. In this paper, a system dynamics simulation model will be used as a tool to represent the operation of a health care facility, including the interaction between the different service areas (emergency room, intensive care unit, wards, operating room), the flow of patients inside the facility, and the condition of the infrastructure systems that supply resources (i.e., water, power, transportation of medical supplies) to maintain the operation of the facility. The results of this study may assist hospital administrators in their disaster preparedness plans, providing information regarding the level of occupancy and patients waiting to enter the service areas.     

Differentiation of rice tungro bacilliform virus strains by restriction analysis and DNA hybridization

The present study evaluates the postnatal efficacy of Momordica charantia peel, pulp, seed and whole fruit extract via assessing the modulation in the biotransformation system enzymes of suckling neonates and lactating mice. The peel, seed or whole fruit extract of Momordica (100 microl/animal/day) independently induced a significant increase in the hepatic levels of glutathione S-transferase (GST) and acid soluble sulfhydryl (-SH) after 14 or 21 days treatment in lactating dams (P < 0.01) and translactationally exposed neonates (P < 0.05). However, the elevation (P < 0.05) in hepatic cytochrome b5 (Cyt. b5) and cytochrome P-450 (Cyt. P-450) levels was observed only in the lactating dams treated with the respective extracts of peel, seed or whole fruit of Momordica. In lactating dams and suckling neonates the modulated levels of biotransformation system enzymes suggest the potential for the translactational passage of active principle(s) and/or metabolites of Momordica.     

Ca and K decorated germanene as hydrogen storage: An ab initio study

The hydrogen storage capacity and performance of Ca and K decorated germanene were studied using density functional theory calculation. The Ca and K adatoms were found to be sufficiently bonded to the germanene without clustering at the hollow site. Further investigation has shown an ionic bonding is apparent based on the charge density difference and Bader charge analysis. Upon adsorption of H₂ on the decorated germanene, it was found that the Ca and K decorated systems could adsorb 8 and 9 H₂ molecules, respectively. The adsorption energies of H₂ molecules were within the Van der Waals energy (400–435 meV), suggesting weak physisorption. The charge density profile revealed that the electron of H₂ moved toward the adatom decoration without leaving the local region of H₂. This suggests that a dipole-dipole interaction was apparent and consistent with the energy range found. Finally, the gravimetric density obtained from the adsorption of H₂ on the decorated germanene shows that this material is a potential for H₂ storage media.     

Estimating crop-specific evapotranspiration using remote-sensing imagery at various spatial resolutions for improving crop growth modelling

By governing water transfer between vegetation and atmosphere, evapotranspiration (ET) can have a strong influence on crop yields. An estimation of ET from remote sensing is proposed by the EUMETSAT ‘Satellite Application Facility’ (SAF) on Land Surface Analysis (LSA). This ET product is obtained operationally every 30 min using a simplified SVAT scheme that uses, as input, a combination of remotely sensed data and atmospheric model outputs. The standard operational mode uses other LSA-SAF products coming from SEVIRI imagery (the albedo, the downwelling surface shortwave flux, and the downwelling surface longwave flux), meteorological data, and the ECOCLIMAP database to identify and characterize the land cover.

With the overall objective of adapting this ET product to crop growth monitoring necessities, this study focused first on improving the ET product by integrating crop-specific information from high and medium spatial resolution remote-sensing data. A Landsat (30 m)-based crop type classification is used to identify areas where the target crop, winter wheat, is located and where crop-specific Moderate Resolution Imaging Spectroradiometer (MODIS) (250 m) time series of green area index (GAI) can be extracted. The SVAT model was run for 1 year (2007) over a study area covering Belgium and part of France using this supplementary information. Results were compared to those obtained using the standard operational mode.

ET results were also compared with ground truth data measured in an eddy covariance station. Furthermore, transpiration and potential transpiration maps were retrieved and compared with those produced using the Crop Growth Monitoring System (CGMS), which is run operationally by the European Commission's Joint Research Centre to produce in-season forecast of major European crops. The potential of using ET obtained from remote sensing to improve crop growth modelling in such a framework is studied and discussed.

Finally, the use of the ET product is also explored by integrating it in a simpler modelling approach based on light-use efficiency. The Carnegie–Ames–Stanford Approach (CASA) agroecosystem model was therefore applied to obtain net primary production, dry matter productivity, and crop yield using only LSA-SAF products. The values of yield were compared with those obtained using CGMS, and the dry matter productivity values with those produced at the Flemish Institute for Technological Research (VITO). Results showed the potential of using this simplified remote-sensing method for crop monitoring.     

Ab initio study on hydrogen interaction with calcium decorated silicon carbide nanotube

Ab initio study on the viability of calcium decorated silicon carbide nanotube as a hydrogen storage material was conducted. Calcium strongly adsorbs on silicon carbide nanotube (SiCNT) with a significant binding energy of ?2.83 eV, thus calcium's low cohesive energy and strong binding with SiCNT may prevent Ca to form clusters with other adsorbates. Bader charge analysis also revealed a charge transfer of 1.45e from Ca to SiCNT resulting to calcium's cationic state, which may induce charge polarization to a nearby molecule such as hydrogen. Hydrogen molecule was then allowed to interact with the calcium adatom where it exhibited charge polarization, induced by the electric field from calcium's positive charge. This resulted to a significant binding energy of ?0.22 eV for the first hydrogen molecule. Results reveal that Ca on SiCNT can hold up to 7 hydrogen molecules and can be a promising candidate for a hydrogen storage material.     

Mobile Ad Hoc Network-Enabled Collaboration Framework Supporting Civil Engineering Emergency Response Operations

This paper presents an information-technology-based collaboration framework that facilitates disaster response operations. The collaboration framework incorporates a web collaboration service, radio frequency identification (RFID) tags, a building blackbox system (BBS), a geo-database, and a geographic information system (GIS). Through the integration of these technologies, the framework provides a collaboration medium for first responders, including civil engineers, to cohesively respond to disasters. Access to critical building information, such as construction documents, through the BBS supports assessments of building integrity during disaster response. Building assessment information is stored on RFID tags, which are accessible to first responders through digital devices via a wireless ad hoc network. With on-site assessment information shown on a digital map, decision makers locate, collect, and distribute critical resources through the GIS to first responders. In addition, the decision makers at distributed locations evaluate the incident through discussion sessions, hosted by the web collaboration environment, for integrated decision making. Test-bed simulations for the framework have been carried out with encouraging results at the training ground of the Illinois Fire Service Institute.     

Application of conductive AFM on the electrical characterization of single-bit marginal failure

The challenge to determine the failure mechanism in submicrometer devices has been increasing with transitions in technological processes. Determining the failure mechanism and finding the associated physical defect have become extremely difficult, if not impossible, due to the increased complexity in architecture and the extremely large number of transistors in ICs. In this investigation, the efficiency and the success rate of using conductive atomic force microscope (cAFM) in the localization of defects in 90-nm devices are shown. How the method was utilized to obtain full electrical data on a single-bit failure using the I-V curve sweep mode and how cAFM can be a suitable alternative to the passive voltage contrast method and in-chamber pico-probing were also demonstrated.