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Joseph O Deasy - One of the best experts on this subject based on the ideXlab platform.

  • tu d 224c 05 validation of a linear accelerator source model and Commissioning Process for routine clinical monte carlo calculations
    Medical Physics, 2006
    Co-Authors: K Zakaryan, J Alaly, M Vicic, M Wiesmeyer, Joseph O Deasy
    Abstract:

    Purpose: Many source models for Monte Carlotreatment planning include parameters which are difficult or ambiguous to determine. We developed and tested a straightforward source model and Commissioning Process for clinical Monte Carlo calculations. Method and Materials: Our Commissioning Process of fitting treatment planning system data includes fitting the photon spectrum, electron contamination, penumbra fluence blurring, jaw leakage, and the flattening filter effect. The energy spectrum is fit using a modified Fatigue Life Distribution multiplied by a Fermi. Electron contamination is modeled separately an exponential function, as suggested by Fippel. Penumbral blurring is modeled using a Gaussian filter. Leakage radiation is modeled as a low‐intensity wide‐field monoenergetic source. The flattening filter effect is modeled by multiplying the optimized fluence by a Gaussian reduction. The penumbra and the flattening filter are applied to the fluence map. We tested our methodology on doses produced by a Varian accelerator for 6 MV and 18 MV photons and 5×5, 10×10, and 20×20 cm2field sizes.Results: We found that nine published photon spectra of Varian, Eleckta, and Siemens linear accelerators, ranging in energy from 4 MV to 25 MV could be modeled by the Fatigue Life Distribution with a Fermi cutoff. The agreement between the TPS doses and the commissioned MCdoses were within 2%. Off‐axis energy spectrum softening was unneeded. Conclusion: We have developed a straightforward, yet flexible source modeling system. The Commissioning Process affords a high‐degree of automation with an unambiguous determination of the relevant parameters. Commissioning of clinical Monte Carlotreatment planning systems is facilitated by using a source model which is only as complicated as necessary to accurately simulates dose distributions. Conflict of Interest: This research was partially supported by NIH grant R01 CA90445 and a grant from Sun Nuclear, Corp.

  • TU‐D‐224C‐05: Validation of a Linear Accelerator Source Model and Commissioning Process for Routine Clinical Monte Carlo Calculations
    Medical Physics, 2006
    Co-Authors: K Zakaryan, J Alaly, M Vicic, M Wiesmeyer, Joseph O Deasy
    Abstract:

    Purpose: Many source models for Monte Carlotreatment planning include parameters which are difficult or ambiguous to determine. We developed and tested a straightforward source model and Commissioning Process for clinical Monte Carlo calculations. Method and Materials: Our Commissioning Process of fitting treatment planning system data includes fitting the photon spectrum, electron contamination, penumbra fluence blurring, jaw leakage, and the flattening filter effect. The energy spectrum is fit using a modified Fatigue Life Distribution multiplied by a Fermi. Electron contamination is modeled separately an exponential function, as suggested by Fippel. Penumbral blurring is modeled using a Gaussian filter. Leakage radiation is modeled as a low‐intensity wide‐field monoenergetic source. The flattening filter effect is modeled by multiplying the optimized fluence by a Gaussian reduction. The penumbra and the flattening filter are applied to the fluence map. We tested our methodology on doses produced by a Varian accelerator for 6 MV and 18 MV photons and 5×5, 10×10, and 20×20 cm2field sizes.Results: We found that nine published photon spectra of Varian, Eleckta, and Siemens linear accelerators, ranging in energy from 4 MV to 25 MV could be modeled by the Fatigue Life Distribution with a Fermi cutoff. The agreement between the TPS doses and the commissioned MCdoses were within 2%. Off‐axis energy spectrum softening was unneeded. Conclusion: We have developed a straightforward, yet flexible source modeling system. The Commissioning Process affords a high‐degree of automation with an unambiguous determination of the relevant parameters. Commissioning of clinical Monte Carlotreatment planning systems is facilitated by using a source model which is only as complicated as necessary to accurately simulates dose distributions. Conflict of Interest: This research was partially supported by NIH grant R01 CA90445 and a grant from Sun Nuclear, Corp.

Zhang Yongzh - One of the best experts on this subject based on the ideXlab platform.

Mohamed Alyagoub - One of the best experts on this subject based on the ideXlab platform.

  • supply chain management in building Commissioning Process in accordance with the leadership in energy environmental design leed a case study of ksa construction industry
    International Journal of Supply Chain Management, 2019
    Co-Authors: Mohamed Essamshaawat, Mohamed Alyagoub
    Abstract:

    The Commissioning procedure is one of the most effective Processes used to improve the performance of building systems and equipment, and the supply chain management in construction industry is the main issue in its performance. Coincidentally, the Leadership in Energy and Environmental Design (LEED) values have the same core objective as of Commissioning that is enlightening the building performance. The aim of the current research is to evaluate the building Commissioning Process in accordance with the Leadership in Energy & Environmental Design (LEED) requirements for the new construction projects from contractor’s point of view in order to measure changes needed and spot on the shortcomings in the Process requirements during the life cycle of a project. The building Commissioning Process is a tool to ensure that all building systems have been designed, installed, tested and operated in accordance with the original design and project scope, which ultimately results in producing a better product for the owner and society. A field survey was conducted through a structured questionnaire including 21 Commissioning authority contractors (CxA) who are specialized in building Commissioning. SPSS has been used to analyze the data to present statistical measures. The research concluded that there are some contractors not complying with the building Commissioning requirements steps Process. The results of the data show that the most important requirements that have not adhered by the contractors during the life cycle of a project. Moreover, Performance in the extent and corroboration credit was similar for all owner types, whereas investors performed otherwise from companies and government agencies in the improved Commissioning credit. Practitioners who identify these significances and differences are expected to be better placed to make sustainability-related decisions in building design and construction.

  • Supply Chain Management in Building Commissioning Process in Accordance with the Leadership in Energy & Environmental Design (LEED) – A Case Study of KSA Construction Industry.
    International Journal of Supply Chain Management, 2019
    Co-Authors: Mohamed Essamshaawat, Mohamed Alyagoub
    Abstract:

    The Commissioning procedure is one of the most effective Processes used to improve the performance of building systems and equipment, and the supply chain management in construction industry is the main issue in its performance. Coincidentally, the Leadership in Energy and Environmental Design (LEED) values have the same core objective as of Commissioning that is enlightening the building performance. The aim of the current research is to evaluate the building Commissioning Process in accordance with the Leadership in Energy & Environmental Design (LEED) requirements for the new construction projects from contractor’s point of view in order to measure changes needed and spot on the shortcomings in the Process requirements during the life cycle of a project. The building Commissioning Process is a tool to ensure that all building systems have been designed, installed, tested and operated in accordance with the original design and project scope, which ultimately results in producing a better product for the owner and society. A field survey was conducted through a structured questionnaire including 21 Commissioning authority contractors (CxA) who are specialized in building Commissioning. SPSS has been used to analyze the data to present statistical measures. The research concluded that there are some contractors not complying with the building Commissioning requirements steps Process. The results of the data show that the most important requirements that have not adhered by the contractors during the life cycle of a project. Moreover, Performance in the extent and corroboration credit was similar for all owner types, whereas investors performed otherwise from companies and government agencies in the improved Commissioning credit. Practitioners who identify these significances and differences are expected to be better placed to make sustainability-related decisions in building design and construction.

K Zakaryan - One of the best experts on this subject based on the ideXlab platform.

  • tu d 224c 05 validation of a linear accelerator source model and Commissioning Process for routine clinical monte carlo calculations
    Medical Physics, 2006
    Co-Authors: K Zakaryan, J Alaly, M Vicic, M Wiesmeyer, Joseph O Deasy
    Abstract:

    Purpose: Many source models for Monte Carlotreatment planning include parameters which are difficult or ambiguous to determine. We developed and tested a straightforward source model and Commissioning Process for clinical Monte Carlo calculations. Method and Materials: Our Commissioning Process of fitting treatment planning system data includes fitting the photon spectrum, electron contamination, penumbra fluence blurring, jaw leakage, and the flattening filter effect. The energy spectrum is fit using a modified Fatigue Life Distribution multiplied by a Fermi. Electron contamination is modeled separately an exponential function, as suggested by Fippel. Penumbral blurring is modeled using a Gaussian filter. Leakage radiation is modeled as a low‐intensity wide‐field monoenergetic source. The flattening filter effect is modeled by multiplying the optimized fluence by a Gaussian reduction. The penumbra and the flattening filter are applied to the fluence map. We tested our methodology on doses produced by a Varian accelerator for 6 MV and 18 MV photons and 5×5, 10×10, and 20×20 cm2field sizes.Results: We found that nine published photon spectra of Varian, Eleckta, and Siemens linear accelerators, ranging in energy from 4 MV to 25 MV could be modeled by the Fatigue Life Distribution with a Fermi cutoff. The agreement between the TPS doses and the commissioned MCdoses were within 2%. Off‐axis energy spectrum softening was unneeded. Conclusion: We have developed a straightforward, yet flexible source modeling system. The Commissioning Process affords a high‐degree of automation with an unambiguous determination of the relevant parameters. Commissioning of clinical Monte Carlotreatment planning systems is facilitated by using a source model which is only as complicated as necessary to accurately simulates dose distributions. Conflict of Interest: This research was partially supported by NIH grant R01 CA90445 and a grant from Sun Nuclear, Corp.

  • TU‐D‐224C‐05: Validation of a Linear Accelerator Source Model and Commissioning Process for Routine Clinical Monte Carlo Calculations
    Medical Physics, 2006
    Co-Authors: K Zakaryan, J Alaly, M Vicic, M Wiesmeyer, Joseph O Deasy
    Abstract:

    Purpose: Many source models for Monte Carlotreatment planning include parameters which are difficult or ambiguous to determine. We developed and tested a straightforward source model and Commissioning Process for clinical Monte Carlo calculations. Method and Materials: Our Commissioning Process of fitting treatment planning system data includes fitting the photon spectrum, electron contamination, penumbra fluence blurring, jaw leakage, and the flattening filter effect. The energy spectrum is fit using a modified Fatigue Life Distribution multiplied by a Fermi. Electron contamination is modeled separately an exponential function, as suggested by Fippel. Penumbral blurring is modeled using a Gaussian filter. Leakage radiation is modeled as a low‐intensity wide‐field monoenergetic source. The flattening filter effect is modeled by multiplying the optimized fluence by a Gaussian reduction. The penumbra and the flattening filter are applied to the fluence map. We tested our methodology on doses produced by a Varian accelerator for 6 MV and 18 MV photons and 5×5, 10×10, and 20×20 cm2field sizes.Results: We found that nine published photon spectra of Varian, Eleckta, and Siemens linear accelerators, ranging in energy from 4 MV to 25 MV could be modeled by the Fatigue Life Distribution with a Fermi cutoff. The agreement between the TPS doses and the commissioned MCdoses were within 2%. Off‐axis energy spectrum softening was unneeded. Conclusion: We have developed a straightforward, yet flexible source modeling system. The Commissioning Process affords a high‐degree of automation with an unambiguous determination of the relevant parameters. Commissioning of clinical Monte Carlotreatment planning systems is facilitated by using a source model which is only as complicated as necessary to accurately simulates dose distributions. Conflict of Interest: This research was partially supported by NIH grant R01 CA90445 and a grant from Sun Nuclear, Corp.

Lin Zheng - One of the best experts on this subject based on the ideXlab platform.

  • flooding simulation of hilly pipeline Commissioning Process
    2010 8th International Pipeline Conference Volume 2, 2010
    Co-Authors: Nan Zhang, Jing Gong, Lin Zheng
    Abstract:

    The “pipeline flooding Process”, refer to filling the empty pipe with water or oil when basic facilities’ construction of a pipeline has been completed, is very important for pipeline Commissioning. The pipeline flooding Process becomes more complicated for the long-slope pipe segments of a hilly pipeline because of air entrapped in fluid. The accumulated air in the fluid which is called air pocket can cause significant damage on pump equipments. The existence of air pocket can also provide difficulties for tracking the fluid front and the interface between oil and water because of the effect of air pocket on the velocity profile of fluid. To avoid such difficulties, the only method is to efficiently discharge the accumulated air. Consequently, the location and the volume of air pocket need to be accurately predicted. In this study, a comprehensive two-fluid model was developed for this prediction using the fundamentals of mass balance and momentum transfer in multiphase flow. By taking into account the effect of air pocket, the location and velocity of flooding front, the pressure at each point in the flooding segment can also be calculated. Therefore, the prediction accuracy of this model can be estimated by comparison with the recorded pressure distribution of SCADA. The model was applied for a specific pipeline in China. In comparison with the SCADA data, an adequate prediction from this model was provided.Copyright © 2010 by ASME