Go Iwai

Extension of the Particle Therapy Simulation Framework to Hospital Information Systems and Multi-grid Environments

The Particle Therapy Simulation Framework (PTSIM) is a Geant4-based Monte Carlo simulation framework for particle therapy. The PTSIM provides a common platform to model a beam delivery system and a treatment head with patient data obtained from CT images. The PTSIM had already supported three Japanese proton and ion therapy facilities and three more in other countries The PTSIM allows particle therapy clinicians or researchers to simulate their own facility or an envisioned facility without requiring Geant4 expertise or programming. While Monte Carlo simulation is believed to be the most reliable method of dose calculation in particle therapy, the calculation time is critical in performing the simulation with sufficient statistical accuracy for clinical applications. There-fore, adopting a high-performance computing environment, such as a grid, is essential. In order to provide users with better usability and computer resources, we have developed an extension of the PTSIM in order to coordinate with hospital information systems and multi-grid environments. The extension consists of the PTSIM Web Interface for configuring the PTSIM, the DICOM-RT interface for communicating with a hospital information system of a particle therapy facility, and a Universal Grid Interface for performing a simulation in a multi-grid environment. In the present paper, we describe these three key components in detail.

SAGA-based user environment for distributed computing resources: A universal Grid solution over multi-middleware infrastructures

Abstract This paper demonstrates practical applications based on SAGA–A Simple API for Grid Applications–for distributed computing resources over multi-middleware infrastructures. SAGA provides a high-level programming interface that bridges between applications and Grids as well as local schedulers such as PBS. At the Computing Research Center of KEK, we are playing a role to support not only on-site users, but also domestic university groups in the High Energy and Nuclear Physics (HENP) community. In order to provide a more effective and practical client environment to users, we have developed Grid-adaptive applications based on SAGA as a part of activity in the RE sources li NK age for E -sc I ence (RENKEI) for the general purpose e-Infrastructure using National Research Grid Initiative (NAREGI) middleware. We present the technical details for the user environment demonstrator and discuss the usability by real HENP applications.

The DCBA experiment for studying neutrinoless double beta-decay

In order to search for neutrinoless double beta-decay, the DCBA (Drift Chamber Beta-ray Analyzer) experiment uses a momentum analyzer, which mainly consists of drift chamber and a uniform magnetic field. A beta ray from a source plate make helical trajectory in the drift chamber owing to the magnetic field. Momentum of each beta ray is obtained by three-dimensional track reconstruction. A test prototype called DCBA-T2 has been constructed and operated at KEK. Another prototype DCBA-T3 is also under construction to improve the energy resolution. The results of DCBA-T2 engineering run are described together with the status of DCBA-T3.

SAGA-based file access application over multi-filesystem middleware

This paper describes practical file access applications based on SAGA -- A <u>S</u>imple <u>A</u>PI for <u>G</u>rid <u>A</u>pplications-- for distributed storage resources over multi-file-system middleware. SAGA provides a high-level programming interface to bridge between network file-system middleware as well as accessing a local file-system. The Computing Research Center of KEK uses many data files from physics experiments. For example, large numbers of bubble chamber image files are shared between KEK and Kings College in UK. Our research problem involves displaying a single bubble chamber image file that is divided and stored in the different kinds of file-systems. We use the two types of file-systems that are iRODS --The Integrated <u>R</u>ule-<u>O</u>riented <u>D</u>ata <u>S</u>ystem-- and Gfarm --<u>G</u>rid Data <u>F</u>arm--. To access the middleware, we are developing the SAGA adaptors for the iRODS and Gfarm file-systems. We present the technical details for the user environments and show the usability with real bubble chamber image files.

Managing Distributed Files with RNS in Heterogeneous Data Grids

This paper describes the management of files distributed in heterogeneous Data Grids by using RNS (Resource Namespace Service). RNS provides hierarchical namespace management for name-to-resource mapping as a key technology to use Grid resources for different kinds of middleware. RNS directory entries and junction entries can contain their own XML messages as metadata. We define attribute expressions in XML for the RNS entries and give an algorithm to access distributed files stored within different kinds of Data Grids. The example in this paper shows how our Grid application can retrieve the actual locations of files from the RNS server. An application can also access the distributed files as though they were files in the local file system without worrying about the underlying Data Grids. This approach can be used in a Grid computing system to handle distributed Grid resources.

SAGA-based application to use resources on different Grids

This paper describes practical applications using resources on different kinds of Grid middleware. At the KEK Computing Research Center, many jobs must be submitted for physics simulations involving large number of data files from physics experiments. The available resources of the various Grids should be used in a cooperative way, but specialized knowledge is currently required to use each Grid. Our solution is using SAGA (Simple API for Grid Applications), which provides a unified interface that conceals the differences among the different kinds of Grid middleware. We developed SAGA adaptors for job execution, file management, and catalog services. The job adaptors we created are applied to each kind of Grid middleware: NAREGI, PBSPro, and Torque. The file adaptors support the Data Grids: iRODS and Gfarm. The replica adaptor currently in use is for the catalog service: RNS (Resource Namespace Service) and iRODS. SAGA with the adaptors allows us to utilize the various Grid resources along with local resources without any concerns about the underlying middleware. Technical details and sample applications are described in this paper.

DCBA experiment for searching for neutrinoless double beta decay (I)

A magnetic tracking detector called DCBA (Drift Chamber Beta-ray Analyzer) is being developed at KEK in order to search for neutrinoless double beta decay. Kinetic energy of each beta ray is obtained from its momentum, which is measured with a drift chamber installed in a uniform magnetic field. Energy resolution has been studied using a test prototype DCBA-T2. The study results are briefly described together with the structure and the principle of DCBA detector.

Common platform of Monte Carlo dose calculation on universal grid interface with Geant4 based particle therapy simulation framework

While Monte Carlo (MC) simulation is believed to be the most reliable method of dose calculation in particle therapy, the simulation time is critical in attaining sufficient statistical accuracy for clinical applications. Therefore, parallelization of simulations is essential. This paper describes a common platform of MC dose calculation in grid-distributed computing environments. The platform is flexible and effective for dose calculation in both clinical and research applications for particle therapy. The platform consists of the universal grid interface (UGI) and the Geant4-based particle therapy simulation framework (PTSIM). The UGI, written in Python, provides a command-line interface for job submission, file manipulation, and monitoring in multiple-grid middleware environments. The PTSIM is a single software application for modeling a treatment port with patient data obtained from CT images. The common platform was constructed in grid computing environments using the computing resources in five institutions. The platform utilized these resources through the NAREGI grid middleware under UGI to provide stable computing resources and a common environment for MC dose calculation in particle therapy.

Recent updates and plan in Geant4 based particle therapy system simulation framework

Particle therapy system simulation framework, PTSIM, is a simulation framework based on Geant4 Monte Carlo simulation. It has been developed in the project, “Development of simulation framework for advanced radiotherapy”, funded by the Japan Science and Technology Agency (JST) in the program of Core Research for Evolutional Research and Technology (CREST), from 2003 to 2010. The PTSIM has provided a common platform to model proton and ion therapy facilities, allowing users who are not Geant4 experts to accurately and efficiently run Geant4 simulations with the pre-build configurations. Efforts on further development of PTSIM are still under way to include more functionality and improve the performance. The PTSIM has been upgraded with the extensions in the DICOM-RT interface to coordinate with hospital information system, the Web interface with universal grid environment, etc. In this paper, we report on our activities about these updates and plan for extending the PTSIM functionality with new requirements from users.

A method for reliably managing files with RNS in multi Data Grids

Abstract This paper describes a method for reliably managing files distributed in different kinds of Data Grids with RNS (Resource Namespace Service). RNS provides hierarchical namespace management for name-to-resource mapping as a key technology when using Grid resources for different kinds of middleware. We define attribute expressions in XML for the RNS entries and give algorithms to access distributed files stored within different kinds of Data Grids. The volume of digital data and the size of an individual file are increasing due to the introduction of high-resolution images, high-definition audiovisual files, etc. The reliable storage of such large files is becoming problematic with whole file replication as a failure in the integrity of the file is difficult to localise. Our method involves managing large files in Data Grids by splitting them into smaller units in a traceable manner and then managing the smaller units. The RNS catalog service contains EPR (Endpoint Reference) and metadata that describe the original locations as well as the checksum values. The example in this paper shows how our Grid application can retrieve the actual file locations and the checksum values from the RNS service via SAGA (A Simple API for Grid Applications). An application can access the distributed files as though they were files in the local file-system without worrying about the underlying Data Grids. This approach can be used with various Data Grid systems to enhance file reliability.