SU-GG-T-264: Correction Factor in Output Measurement for Small Fields

2008 ◽  
Vol 35 (6Part13) ◽  
pp. 2786-2786
Author(s):  
S Srivastava ◽  
I Das ◽  
C Cheng
Keyword(s):  
Correction Factor ◽  
Output Measurement ◽  
Small Fields

SU-F-T-572: Small Fields Output Factors Measurement and Correction Factor Determination for Several Active and Passive Detectors

2016 ◽  
Vol 43 (6Part22) ◽  
pp. 3595-3595
Author(s):  
D Sharma ◽  
S Sharma ◽  
R Chowdhary ◽  
S Pilakkal ◽  
S Rashal
Keyword(s):  
Correction Factor ◽  
Small Fields ◽  
Output Factors

scholarly journals The effect of SSD, Field size, Energy and Detector type for Relative Output Factor measurement in small photon beams as compared with Monte Carlo simulation

2019 ◽  
Vol 25 (2) ◽  
pp. 101-110
Author(s):  
Itumeleng Setilo ◽  
Oluwaseyi Michael Oderinde ◽  
Freek Cp du Plessis
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Field Size ◽  
Photon Beams ◽  
Output Measurement ◽  
Voxel Size ◽  
Output Factor ◽  
Ion Chamber ◽  
Small Fields ◽  
Mc Simulation

Abstract Introduction: Small fields photon dosimetry is associated with many problems. Using the right detector for measurement plays a fundamental role. This study investigated the measurement of relative output for small photon fields with different detectors. It was investigated for three-photon beam energies at SSDs of 90, 95, 100 and 110 cm. As a benchmark, the Monte Carlo simulation was done to calculate the relative output of these small photon beams for the dose in water. Materials and Methods: 6, 10 and 15 MV beams were delivered from a Synergy LINAC equipped with an Agility 160 multileaf collimator (MLC). A CC01 ion chamber, EFD-3G diode, PTW60019 microdiamond, EBT2 radiochromic film, and EDR2 radiographic film were used to measure the relative output of the linac. Measurements were taken in water for the CC01 ion chamber, EFD-3G diode, and the PTW60019. Films were measured in water equivalent RW3 phantom slabs. Measurements were made for 1 × 1, 2 × 2, 3 × 3, 4 × 4, 5 × 5 and a reference field of 10 × 10 cm2. Field sizes were defined at 100cm SSD. Relative output factors were also compared with Monte Carlo (MC) simulation of the LINAC and a water phantom model. The influence of voxel size was also investigated for relative output measurement. Results and Discussion: The relative output factor (ROF) increased with energy for all fields large enough to have lateral electronic equilibrium (LEE). This relation broke down as the field sizes decreased due to the onset of lateral electronic disequilibrium (LED). The high-density detector, PTW60019 gave the highest ROF for the different energies, with the less dense CC01 giving the lowest ROFs. Conclusion: These are results compared to MC simulation, higher density detectors give higher ROF values. Relative to water, the ROF measured with the air-chamber remained virtually unchanged. The ROFs, as measured in this study showed little variation due to increased SSDs. The effect of voxel size for the Monte Carlo calculations in water does not lead to significant ROF variation over the small fields studied.

scholarly journals Thermodilution Cardiac Output — A Systematic Error

1981 ◽  
Vol 9 (2) ◽  
pp. 135-139 ◽  
Author(s):  
W. B. Runciman ◽  
A. H. Ilsley ◽  
J. G. Roberts
Keyword(s):  
Cardiac Output ◽  
Systematic Error ◽  
Correction Factor ◽  
Cardiac Output Measurement ◽  
Thermodilution Technique ◽  
Output Measurement ◽  
Thermodilution Cardiac Output ◽  
Thermal Indicator ◽  
Wide Range ◽  
Cardiac Output Measurements

The purpose of this study was to examine the mechanism and magnitude of a systematic error in thermodilution cardiac output measurement. One hundred and seventy-one thermodilution cardiac output measurements in dogs using a Swan-Ganz catheter were compared with simultaneously made dye dilution measurements under different conditions over a wide range of cardiac outputs. A systematic error with the thermodilution technique was confirmed and was almost identical to that observed in the literature. It is proposed that its mechanism is loss of thermal indicator between the injectate orifice and detection. Application of a further correction factor for thermal indicator loss is suggested.

Problems and prospects of development of small fields in Russia

2019 ◽  
pp. 22-30
Author(s):  
A.F. Andreev ◽  
◽  
A.A. Daudova ◽  
A.A. Biketova ◽  
◽  
...  
Keyword(s):  
Small Fields

Performance enhancement of normal contact ratio gearing system through correction factor

2019 ◽  
Vol 13 (3) ◽  
pp. 5242-5258
Author(s):  
R. Ravivarman ◽  
K. Palaniradja ◽  
R. Prabhu Sekar
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Correction Factor ◽  
Bending Strength ◽  
Performance Enhancement ◽  
Transmission Ratio ◽  
Contact Ratio ◽  
Element Analysis ◽  
Normal Contact ◽  
Root Region

As lined, higher transmission ratio drives system will have uneven stresses in the root region of the pinion and wheel. To enrich this agility of uneven stresses in normal-contact ratio (NCR) gearing system, an enhanced system is desirable to be industrialized. To attain this objective, it is proposed to put on the idea of modifying the correction factor in such a manner that the bending strength of the gearing system is improved. In this work, the correction factor is modified in such a way that the stress in the root region is equalized between the pinion and wheel. This equalization of stresses is carried out by providing a correction factor in three circumstances: in pinion; wheel and both the pinion and the wheel. Henceforth performances of this S+, S0 and S- drives are evaluated in finite element analysis (FEA) and compared for balanced root stresses in parallel shaft spur gearing systems. It is seen that the outcomes gained from the modified drive have enhanced performance than the standard drive.

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