A novel evaluation technique for radiochromic films based on Cosine-Distance analysis: Feasibilities of wide range photon dosimetry and postal intercomparison in lieu of conventional TLD chips

2021 ◽  
pp. 110005
Author(s):  
Bhaskar Mukherjee ◽  
Uday Bhonsle
2019 ◽  
Vol 186 (2-3) ◽  
pp. 357-361
Author(s):  
V Dufek ◽  
I Horakova ◽  
I Koniarova

Abstract In radiotherapy, radiochromic films can be used for verification of delivery of dose distributions calculated by treatment planning systems. The main objective of this work was to compare three different techniques for evaluation of dose distributions for prostate cancer treatment plans using radiochromic EBT3 films. These techniques are: red channel evaluation taking into account only a response of irradiated film (R), red channel evaluation taking into account a response of unirradiated and irradiated film (Rcor) and multichannel evaluation in FilmQA software (RGB). Also comparison between film and MatriXX measurement was performed. Comparison showed that gamma analysis passing rates strongly depend on evaluation technique and on a model of scanner for digitizing films. The highest gamma passing rates were obtained with red channel evaluation taking into account a response of unirradiated and irradiated film using Epson V750 scanner (Rcor) and multichannel evaluation in FilmQA using Epson 11000XL scanner.


2021 ◽  
Author(s):  
M. N. Rajpar ◽  
M. Zakaria

Abstract To determine the conservation status and population structure of avian species living in various subtropical broadleaved urban forests, namely Dob Ghar, Kamal Khan, Kityari, Palamar, Seya Sar and Shahabad of Pakistan, we aimed to use the distance sampling line transect process. To avoid double counting of the same bird individual, a total of 180 counting points were set at 250 m from each other. In all, between December 2017 and November 2018, 2,879 individuals representing 53 species, 28 families and 9 orders were detected. One species was vulnerable (VU) out of 53 bird species, while the remaining 52 species were the least concerned (LC). In particular, the results of the distance analysis indicate that, in six subtropical broad-leaved forests, the bird population can vary. For eg, Palamar (0.954 ± 0.221 birds/ha) and Kityari (0.938 ± 0.162 birds/ha) were densely populated by bird species, while Kamal Khan (0.102 ± 0.178 birds/ha) was less concerm. Similarly, the CAP findings showed that bird species in Dob Ghar were more diverse (H’ = 33.92 ± 1.368) and equally distributed (E = 0.9657 ± 0.004) and that the Shahabad ecosystem was rich in bird species (R1 = 8.007 ± 0.053) compared to other habitats. In addition, the length of the twigs and topological changes in the dendrogram have shown that bird diversity may vary from habitat to habitat. The bird species were classified into eight foraging guilds. Insectivores were the most abundant bird species using all habitats in abundance. By cons, Carnivore/Piscivore/Insectivore averted to use the forest habitats Dob Ghar and Frugivore Kamal Khan and Dob Ghar. The findings of this study revealed that broad-leaved subtropical urban forests are home to a wide range of avian species. However, habitat selection among bird species varied across habitats according to vegetation structure and composition, food resources, adjoining habitats, and human settlements.


Weed Science ◽  
1970 ◽  
Vol 18 (5) ◽  
pp. 608-611 ◽  
Author(s):  
H. W. Hilton ◽  
Edith Lawrence

An 1130 IBM computer was used to process data from experimental plots to evaluate performance of preemergence herbicides in Hawaiian sugarcane fields (planted with varieties of four Saccharum spp.). The evaluation technique compares performance of experimental herbicides with the performance of three standard herbicides [2-(ethyl-amino)-4-(isopropylamino)-6-(methylthio)-s-triazine (ametryne), 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine), and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron)] under a wide range of environmental conditions. Under most conditions the substituted triazine 2-(sec-butylamino)-4-(ethylamino)-6-methoxy-s-triazine (GS-14254) gave better total weed control without crop toxicity than any of the three standards, and was particularly well-suited to regions of high rainfall.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1085 ◽  
Author(s):  
Wojciech Cieslik ◽  
Filip Szwajca ◽  
Wojciech Golimowski ◽  
Andrew Berger

Electrification of powertrain systems offers numerous advantages in the global trend in vehicular applications. A wide range of energy sources and zero-emission propulsion in the tank to wheel significantly add to electric vehicles’ (EV) attractiveness. This paper presents analyses of the energy balance between micro-photovoltaic (PV) installation and small electric vehicle in real conditions. It is based on monitoring PV panel’s energy production and car electricity consumption. The methodology included energy data from real household PV installation (the most common renewable energy source in Poland), electric vehicle energy consumption during real driving conditions, and drivetrain operating parameters, all collected over a period of one year by indirect measuring. A correlation between energy produced by the micro-PV installation and small electric car energy consumption was described. In the Winter, small electric car energy consumption amounted to 14.9 kWh per 100 km and was 14% greater than summer, based on test requirements of real driving conditions. The 4.48 kW PV installation located in Poznań produced 4101 kWh energy in 258 days. The calculation indicated 1406 kWh energy was available for EV charging after household electricity consumption subtraction. The zero-emission daily distance analysis was done by the simplified method.


Author(s):  
R.W. Horne

The technique of surrounding virus particles with a neutralised electron dense stain was described at the Fourth International Congress on Electron Microscopy, Berlin 1958 (see Home & Brenner, 1960, p. 625). For many years the negative staining technique in one form or another, has been applied to a wide range of biological materials. However, the full potential of the method has only recently been explored following the development and applications of optical diffraction and computer image analytical techniques to electron micrographs (cf. De Hosier & Klug, 1968; Markham 1968; Crowther et al., 1970; Home & Markham, 1973; Klug & Berger, 1974; Crowther & Klug, 1975). These image processing procedures have allowed a more precise and quantitative approach to be made concerning the interpretation, measurement and reconstruction of repeating features in certain biological systems.


Author(s):  
E.D. Wolf

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.


Author(s):  
B. J. Hockey

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.


Author(s):  
H. Todokoro ◽  
S. Nomura ◽  
T. Komoda

It is interesting to observe polymers at atomic size resolution. Some works have been reported for thorium pyromellitate by using a STEM (1), or a CTEM (2,3). The results showed that this polymer forms a chain in which thorium atoms are arranged. However, the distance between adjacent thorium atoms varies over a wide range (0.4-1.3nm) according to the different authors.The present authors have also observed thorium pyromellitate specimens by means of a field emission STEM, described in reference 4. The specimen was prepared by placing a drop of thorium pyromellitate in 10-3 CH3OH solution onto an amorphous carbon film about 2nm thick. The dark field image is shown in Fig. 1A. Thorium atoms are clearly observed as regular atom rows having a spacing of 0.85nm. This lattice gradually deteriorated by successive observations. The image changed to granular structures, as shown in Fig. 1B, which was taken after four scanning frames.


Author(s):  
T. Miyokawa ◽  
S. Norioka ◽  
S. Goto

Field emission SEMs (FE-SEMs) are becoming popular due to their high resolution needs. In the field of semiconductor product, it is demanded to use the low accelerating voltage FE-SEM to avoid the electron irradiation damage and the electron charging up on samples. However the accelerating voltage of usual SEM with FE-gun is limited until 1 kV, which is not enough small for the present demands, because the virtual source goes far from the tip in lower accelerating voltages. This virtual source position depends on the shape of the electrostatic lens. So, we investigated several types of electrostatic lenses to be applicable to the lower accelerating voltage. In the result, it is found a field emission gun with a conical anode is effectively applied for a wide range of low accelerating voltages.A field emission gun usually consists of a field emission tip (cold cathode) and the Butler type electrostatic lens.


Author(s):  
David A. Ansley

The coherence of the electron flux of a transmission electron microscope (TEM) limits the direct application of deconvolution techniques which have been used successfully on unmanned spacecraft programs. The theory assumes noncoherent illumination. Deconvolution of a TEM micrograph will, therefore, in general produce spurious detail rather than improved resolution.A primary goal of our research is to study the performance of several types of linear spatial filters as a function of specimen contrast, phase, and coherence. We have, therefore, developed a one-dimensional analysis and plotting program to simulate a wide 'range of operating conditions of the TEM, including adjustment of the:(1) Specimen amplitude, phase, and separation(2) Illumination wavelength, half-angle, and tilt(3) Objective lens focal length and aperture width(4) Spherical aberration, defocus, and chromatic aberration focus shift(5) Detector gamma, additive, and multiplicative noise constants(6) Type of spatial filter: linear cosine, linear sine, or deterministic


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