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  1. Article ; Online: Monte Carlo and experimental dosimetric study of the mHDR-v2 brachytherapy source.

    Chandola, Rakesh M / Tiwari, Samit / Kowar, Manoj K / Choudhary, Vivek

    Journal of cancer research and therapeutics

    2010  Volume 6, Issue 4, Page(s) 421–426

    Abstract: The conventional treatment planning system (TPS) gives analytical calculations with ± 15 to 20% dose, which may lead to over exposure of critical organs or under dose of target. It is to obtain dose distribution parameters of nucletron high dose rate ( ... ...

    Abstract The conventional treatment planning system (TPS) gives analytical calculations with ± 15 to 20% dose, which may lead to over exposure of critical organs or under dose of target. It is to obtain dose distribution parameters of nucletron high dose rate (HDR) microselectron v2 (mHDR-v2) 192 Ir brachytherapy source by experiment and by calculated study using Monte Carlo (MC) EGSnrc code, and to find the similarity between them, and with any past study. To validate data, another MC GEANT4 study done in this work on the same source is also presented. Different software of the computer e.g. paint, excel, etc are employed for preparation of figures and graphs. The measured study of the source was done using an in-air ionization chamber, water phantom, and measurement set-up, while the calculated study was done by modeling the set up of the measured study by using the MC EGSnrc and GEANT4. Mean and probability are used in calculation of average values, and calculation of the uncertainties in result and discussion. The measured and calculated values of dose rate constant, radial dose function, and 2D anisotropy function were found to be in agreement with each other as well as with published data. The results of this study can be used as input to TPS.
    MeSH term(s) Brachytherapy/instrumentation ; Humans ; Monte Carlo Method ; Neoplasms/radiotherapy ; Radiotherapy Dosage
    Language English
    Publishing date 2010-10
    Publishing country India
    Document type Journal Article ; Review
    ZDB-ID 2187633-2
    ISSN 1998-4138 ; 0973-1482
    ISSN (online) 1998-4138
    ISSN 0973-1482
    DOI 10.4103/0973-1482.77068
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Experimental and Monte Carlo study of the effect of the presence of dry air, cortical bone inhomogeneities and source position on dose distribution of the mHDR-v2 source.

    Chandola, Rakesh M / Tiwari, Samit / Beck, Manjula / Chandrakar, Pradeep Kumar / Thakur, Suresh Kumar

    Journal of cancer research and therapeutics

    2012  Volume 8, Issue 4, Page(s) 555–560

    Abstract: Background: Recently it was data wise established that there is a considerable dose difference due to source position from the surface of the patient, and due to the presence of inhomogeneities.: Aim: It aims at to find out the dose difference due to ...

    Abstract Background: Recently it was data wise established that there is a considerable dose difference due to source position from the surface of the patient, and due to the presence of inhomogeneities.
    Aim: It aims at to find out the dose difference due to source position, and inhomogenieties in water phantom of high dose rate (HDR)(192) Ir mHDR-v2 source by experiment and by Monte Carlo (MC) simulation GEANT4 code.
    Materials and methods: The measured study of the source was done using an in-air ionization chamber, water phantom while the calculated study was done by modeling the water phantom and its water, inhomogeneities, position of source, and points of calculation.
    Results: The measured and calculated dose differences are 5.48 to 6.46% and 5.43 to 6.44% respectively higher in the presence of dry air and 4.40 to 4.90% and 4.38 to 4.88% respectively lower in the presence of cortical bone. However, for the study of the effect of source position on dose distribution, when the source was positioned at a 1 cm distance from the surface of water phantom, the near points between 1 cm and 2 cm are 2 to 3.5% and 2.1-3.7% underdose and for distant points from 3 cm to 8 cm from the source are 4 to 15% and 4.1 to 15.8% underdose for measured and calculated studies, respectively, to the dose when the source was positioned at midpoint of water phantom.
    Conclusion: These results can be used in the treatment planning system.
    MeSH term(s) Air ; Bone and Bones/radiation effects ; Humans ; Iridium Radioisotopes/therapeutic use ; Monte Carlo Method ; Phantoms, Imaging ; Radiation Dosage
    Chemical Substances Iridium Radioisotopes
    Language English
    Publishing date 2012-10
    Publishing country India
    Document type Journal Article
    ZDB-ID 2187633-2
    ISSN 1998-4138 ; 0973-1482
    ISSN (online) 1998-4138
    ISSN 0973-1482
    DOI 10.4103/0973-1482.106536
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Analysis of ESAFORM 2021 cup drawing benchmark of an Al alloy, critical factors for accuracy and efficiency of FE simulations.

    Habraken, Anne Marie / Aksen, Toros Arda / Alves, José L / Amaral, Rui L / Betaieb, Ehssen / Chandola, Nitin / Corallo, Luca / Cruz, Daniel J / Duchêne, Laurent / Engel, Bernd / Esener, Emre / Firat, Mehmet / Frohn-Sörensen, Peter / Galán-López, Jesús / Ghiabakloo, Hadi / Kestens, Leo A I / Lian, Junhe / Lingam, Rakesh / Liu, Wencheng /
    Ma, Jun / Menezes, Luís F / Nguyen-Minh, Tuan / Miranda, Sara S / Neto, Diogo M / Pereira, André F G / Prates, Pedro A / Reuter, Jonas / Revil-Baudard, Benoit / Rojas-Ulloa, Carlos / Sener, Bora / Shen, Fuhui / Van Bael, Albert / Verleysen, Patricia / Barlat, Frederic / Cazacu, Oana / Kuwabara, Toshihiko / Lopes, Augusto / Oliveira, Marta C / Santos, Abel D / Vincze, Gabriela

    International journal of material forming

    2022  Volume 15, Issue 5, Page(s) 61

    Abstract: This article details the ESAFORM Benchmark 2021. The deep drawing cup of a 1 mm thick, AA 6016-T4 sheet with a strong cube texture was simulated by 11 teams relying on phenomenological or crystal plasticity approaches, using commercial or self-developed ... ...

    Abstract This article details the ESAFORM Benchmark 2021. The deep drawing cup of a 1 mm thick, AA 6016-T4 sheet with a strong cube texture was simulated by 11 teams relying on phenomenological or crystal plasticity approaches, using commercial or self-developed Finite Element (FE) codes, with solid, continuum or classical shell elements and different contact models. The material characterization (tensile tests, biaxial tensile tests, monotonic and reverse shear tests, EBSD measurements) and the cup forming steps were performed with care (redundancy of measurements). The Benchmark organizers identified some constitutive laws but each team could perform its own identification. The methodology to reach material data is systematically described as well as the final data set. The ability of the constitutive law and of the FE model to predict Lankford and yield stress in different directions is verified. Then, the simulation results such as the earing (number and average height and amplitude), the punch force evolution and thickness in the cup wall are evaluated and analysed. The CPU time, the manpower for each step as well as the required tests versus the final prediction accuracy of more than 20 FE simulations are commented. The article aims to guide students and engineers in their choice of a constitutive law (yield locus, hardening law or plasticity approach) and data set used in the identification, without neglecting the other FE features, such as software, explicit or implicit strategy, element type and contact model.
    Language English
    Publishing date 2022-07-15
    Publishing country France
    Document type Journal Article
    ZDB-ID 2423930-6
    ISSN 1960-6214 ; 1960-6206
    ISSN (online) 1960-6214
    ISSN 1960-6206
    DOI 10.1007/s12289-022-01672-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Monte Carlo study of dosimetric parameters and dose distribution effect of inhomogeneities and source position of GammaMed Plus source.

    Chandola, Rakesh M / Tiwari, Samit / Painuly, Nirmal K / Choudhary, Vivek / Azad, Surendra K / Beck, Manjula

    Journal of cancer research and therapeutics

    2011  Volume 7, Issue 1, Page(s) 29–34

    Abstract: Background: The conventional treatment planning system (TPS) gives analytical calculations with approximately ± 15-20% dose uncertainty, which may lead to over exposure of critical organs or under dose of target as well as the presence of ... ...

    Abstract Background: The conventional treatment planning system (TPS) gives analytical calculations with approximately ± 15-20% dose uncertainty, which may lead to over exposure of critical organs or under dose of target as well as the presence of inhomogeneities, and the position of source affects the exact dose calculation like in breast and intraluminal brachytherapy.
    Aim: To obtain dose distribution parameters of GammaMed Plus high dose rate (HDR) 192 Ir source using Monte Carlo (MC) EGSnrc and GEANT4 codes as well as to find the effect on dose distribution due to source position, and due to presence of air and cortical bone by using MC GEANT4 code, and to find the similarity of both studies with any past study of any HDR brachytherapy source for either as input to TPS or verification of TPS calculations.
    Settings and design: It is done using different software of the computer, e.g., excel, MS word, etc.
    Materials and methods: The source, source position for different studies, water phantom, water characteristics, points of measurements, air and cortical bone inhomogeneities, and position of inhomogeneities were simulated.
    Statistical analysis used: For uncertainties calculation, mean and probability are used.
    Results: The calculated dose rate constant, radial dose function, and 2D anisotropy function of the source show similarity with published data. Calculated dose distribution differences due to presence of air and cortical bone, and position of source in water phantom also show similarity with published data.
    Conclusion: These results can either be implemented in TPS or can be used for verification of TPS calculations.
    MeSH term(s) Air ; Brachytherapy/instrumentation ; Computer Simulation ; Dose-Response Relationship, Radiation ; Humans ; Iridium Radioisotopes/administration & dosage ; Monte Carlo Method ; Radiometry ; Radiotherapy Planning, Computer-Assisted ; Software ; Water
    Chemical Substances Iridium Radioisotopes ; Water (059QF0KO0R)
    Language English
    Publishing date 2011-01
    Publishing country India
    Document type Journal Article
    ZDB-ID 2187633-2
    ISSN 1998-4138 ; 0973-1482
    ISSN (online) 1998-4138
    ISSN 0973-1482
    DOI 10.4103/0973-1482.80453
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Experimental and Monte Carlo study of the effect of the presence of dry air, cortical bone inhomogeneities and source position on dose distribution of the mHDR-v2 source

    Rakesh M Chandola / Samit Tiwari / Manjula Beck / Pradeep Kumar Chandrakar / Suresh Kumar Thakur

    Journal of Cancer Research and Therapeutics, Vol 8, Iss 4, Pp 555-

    2012  Volume 560

    Abstract: Background: Recently it was data wise established that there is a considerable dose difference due to source position from the surface of the patient, and due to the presence of inhomogeneities. Aim: It aims at to find out the dose difference due to ... ...

    Abstract Background: Recently it was data wise established that there is a considerable dose difference due to source position from the surface of the patient, and due to the presence of inhomogeneities. Aim: It aims at to find out the dose difference due to source position, and inhomogenieties in water phantom of high dose rate (HDR) 192 Ir mHDR-v2 source by experiment and by Monte Carlo (MC) simulation GEANT4 code. Materials and Methods: The measured study of the source was done using an in-air ionization chamber, water phantom while the calculated study was done by modeling the water phantom and its water, inhomogeneities, position of source, and points of calculation. Results: The measured and calculated dose differences are 5.48 to 6.46% and 5.43 to 6.44% respectively higher in the presence of dry air and 4.40 to 4.90% and 4.38 to 4.88% respectively lower in the presence of cortical bone. However, for the study of the effect of source position on dose distribution, when the source was positioned at a 1 cm distance from the surface of water phantom, the near points between 1 cm and 2 cm are 2 to 3.5% and 2.1-3.7% underdose and for distant points from 3 cm to 8 cm from the source are 4 to 15% and 4.1 to 15.8% underdose for measured and calculated studies, respectively, to the dose when the source was positioned at midpoint of water phantom. Conclusion: These results can be used in the treatment planning system.
    Keywords Brachytherapy ; GEANT4 ; HDR ; inhomogeneity ; Monte Carlo ; Neoplasms. Tumors. Oncology. Including cancer and carcinogens ; RC254-282 ; Internal medicine ; RC31-1245 ; Medicine ; R
    Subject code 690
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Medknow Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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