Evaluation of the radiological risk in cargo scanning by comparison with known biological consequences

This study proposes a quick, easy, and low-cost method that can be used to assess the radiological safety of an irradiation line used for cargo and container inspection facilities. The radiation-emitting equipment used was a Smiths Heimam particle accelerator model HCVP4029 operating at 4.5 MeV. The radiation dose measurements were performed using a personal radiation monitor Ultra Radac mod MRAD 111 (Geiger–Muller). The ambient equivalent dose H*(10) was estimated for two facilities: A (real) (1.12E-03 mSv per scan) and B (fictitious) (3.25E-03 mSv per scan). The dimensionless factor R, which represents a ratio between two specific scanning (Ss) quantities regarding the facilities A and B, is introduced as a reference for assessing the level of radiological safety. This study compares facilities A and B by using a simple alternative safety assessment based on the R factor. The dimensionless R-value appears to be able to facilitate both the personnel’s and the general public’s perception of risk levels, even with no fixed scale.

Database of rainfall erosivity factor for 141 locations in Brazil.

Soil erosion is a serious agricultural and environmental problem considered as a threat to sustainable development around the world. Rainfall is the primary cause of soil erosion, what leads the knowledge of its potential to cause soil erosion (rainfall erosivity – R-factor) to be a valuable tool for the design of land conservation best practices. As Brazil has a lack of information about rainfall erosivity, the present paper has determined the R-factor of 141 pluviographic stations distributed over Brazilian territory. Initially, erosive rainfalls were identified, and then the EI30 erosivity index was used to obtain the rainfall erosivity values. Regression models for the estimation of rainfall erosivity using daily rainfall data were established based on the correlation between the monthly average values of erosivity and the modified Fournier index. Results showed that the annual rainfall erosivity in the Brazilian stations analyzed ranged from 368.7 to 16,850.6 MJ mm ha-1 h-1 year-1. The results presented help to expand information about the spatial distribution of rainfall erosivity in Brazil, contributing to better conservation planning of land use.

Response Reduction Factor for Lateral Load Resisting Frames with Vertical Discontinuity of Asymmetrical Structure

In recent times, the RC building construction with vertical discontinuity that is floating column structures are unavoidable feature and increases trends day by day. To reduce lateral forces the earthquake resistance structures are designed so the response reduction factor (R) is used to determine these lateral forces by using base shear values. The R factor depends upon the overstrength factor, ductility factor, redundancy factor also the sizes of columns, types of soil, zones and load transferring path, etc. The IS code provides response reduction factor only for OMRF and SMRF along with other structures like Braced frame system, Structural wall system, Dual system, Flat slab structure wall system, etc. so there are no codal provisions for floating column structures. Thus it is essential to study the real behaviours of RC buildings with discontinuity in load transferring path through non-linear static analysis, so the present research work is done on trying to find R factor for vertical discontinuous asymmetrical structure for different soil conditions and different positions of floating column using moment resisting frames. And the structure is analyzed by response spectrum analysis and non-linear static analysis using SAP2000 software.

Estimation of Temporal R-factor Based on Monthly Precipitation Data

This study assesses temporal variation in rainfall erosivity of Gurushikhar, Rajasthan, (India) on a monthly precipitation basis in the form of the USLE/RUSLE R-factor. The objective of the paper is to theoretically calculate rainfall erosivity when the unavailability of high temporal resolution pluviographic rainfall data such as Indian condition. In the study, the rainfall erosivity has been calculated using the Modified Fourier Index. The results show that the annual rainfall erosivity factor (R) value highest in the year 2017 and lowest in 1974. Conferring to an examination through NASA, earth’s global superficial temperatures in 2017 ranked as second warmest since 1880. Therefore, the rainfall amount was more in 2017 compared to past years, and also rainfall erosivity value suddenly increased in 2017, achieved the highest value. They concluded that the heavy precipitation events in the year are lead to an increase in rainfall erosivity value and risk of soil erosion.

Approach of the annual erosivity in North Chile

The Norte Grande of Chile (17°S-29°S) features arid regions, where rainfall is generally convective with high spatial and temporal variability, which is the cause of floods with large amounts of sediments due to water erosion. The most relevant factor in erosive processes in arid regions is erosivity, which can be quantified by the RUSLE R-factor, but precipitation data are required every 30 minutes, however, these records are limited. The ones that are available are not enough to characterize it spatially. Consequently, the objective of this study is to evaluate regression models of the annual erosivity using rainfall aggressiveness indices as an explanatory variable, with the aim of analyzing the spatial behavior of erosion. Correlations were made between the maximum intensity in 30 minutes (I30) to the maximum intensity in one hour (I60), which were useful for calculating the R-factor for stations with hourly data by applying a correction factor to I60 determined by the correlations. Four regression models were established for each of the six aggressiveness indices and a relationship was selected through validation, using stations with few years of continuous recording. The selected equation allowed generating 103 spatially distributed erositivy-values, which served to make a subsequent co-kriging, in order to make a spatial analysis of rainfall erosivity. Results showed that there are under-estimations of I30, however, they are considered acceptable due to the efficiency obtained (Nash-Sutcliffe = 0.787). The calculated R-factor data-points allowed selection of the best-fit potential equation, which uses the mean annual rainfall as a predictor

Evaluation of R-Factor for 5 Storey RC Frame (IMRF) Building

According to IS 1893 part 1 (2016), the philosophy of earthquake resistant structures allows for some damages and inelastic lateral displacement in the structure for energy dissipation during an earthquake. The non-linear behaviour of elements in the structure plays a crucial role in earthquake resistance. There are three detailed classes for distinct seismic zones in different national codes. In India, the draught IS 13920 advocated the usage of IMRF (intermediate moment resisting frame) in zones II and III. The 5 story IMRF is designed and detailed as per IS 1893 (part 1) 2016, IS 13920 (2016), IS 1893 draft, IS 13920 draft, IS 456 (2000). In addition, nonlinear static pushover analysis was performed on IMRF and SMRF RC frame buildings in accordance with FEMA 356. (Displacement Coefficient method) During the analysis, two distinct load patterns (i) parabolic as per IS 1893 (part 1) 2016 (ii) fundamental mode shape are utilised, and the influence of p-delta is also taken into account when evaluating the response reduction factor. The analysed R-factor for studied frame building for fundamental mode shape loading was found to be near to the initial estimated R-factor during the design.

The Response Modification Factor for Seismic Design of Integral Abutment Bridges

The response modification factor (R factor) is a crucial parameter for calculating the design seismic forces applied to a bridge structure. This factor considers the nonlinear performance of bridges during strong ground motions. Conventional bridge structures rely on the substructure components to resist earthquake forces. Accordingly, there are R factors available in the design codes based on the type of bridge substructure system. Lateral load resisting system of Integral Abutment Bridges (IABs) in the longitudinal direction is more complex than ordinary bridges. It involves the contributions from soils behind the abutments and soil/structure interaction (SSI) in addition to existing rigid connection between the superstructure and abutments. There is no R factor available in any design code throughout the world for IABs in the longitudinal direction that considers all these parameters. In this research, the Federal Emergency Management Agency publication FEMA P695 methodology has been applied to estimate the R factor for IABs. It is found that 3.5 could be a safe and valid R factor in the longitudinal direction for seismic design of such bridges.

Sensitivity of quantitative symmetry measurement algorithms for convergent beam electron diffraction technique

We investigate the sensitivity of symmetry quantification algorithms based on the profile R-factor (Rp) and the normalized cross-correlation (NCC) coefficient (γ). A DM (Digital Micrograph©) script embedded in the Gatan digital microscopy software is used to develop the symmetry quantification program. Using the Bloch method, a variety of CBED patterns are simulated and used to investigate the sensitivity of symmetry quantification algorithms. The quantification results show that two symmetry quantification coefficients are significantly sensitive to structural changes even for small strain values of < 1%.

Effect of Solvent on Protonation Equilibria of L-Serine and L-Tryptophan in Ethylene Glycol-Water Mixtures

Protonation equilibria of L-serine and L-tryptophan in varying compositions (0.0-50.0 % v/v) of ethylene glycol-water mixtures were investigated pH-metrically. Titrations were performed at 303.0 K and the ionic strength of the medium was maintained at 0.16 mol L-1 using sodium chloride. The protonation constants have been calculated with the computer program MINIQUAD 75 and are selected based on statistical parameters. The best fit chemical models of the protonation equilibria were based on crystallographic R-factor, χ2, skewness and kurtosis. The protonation constants of L-serine and L-tryptophan change linearly with increasing ethylene glycol content. This is attributed to the dielectric constant of the medium.