Frontier Project Research Articles

Design and fabrication of the high-power RF transmission line into the PEFP linac tunnel

The 100-MeV proton linear accelerator (linac) for the Proton Engineering Frontier Project (PEFP) has been developed and will be installed at the Gyeong-ju site. For the linac, a total of 11 sets of RF systems are required, and the waveguide layout was fixed to install high-power RF (HPRF) systems. One of the important interfaces with the building construction is the high-power radio-frequency (HPRF) transmission line embedded in the tunnel, which is used to transmit 1-MW RF power to each cavity in the tunnel. The waveguide section penetrating into the linac tunnel was designed with a bending structure for radiation shielding, and the dependence of its voltage standing-wave ratio (VSWR) on the chamfer length of the bending was calculated. The HPRF transmission line was fabricated into a piece of waveguide to prevent moisture and any foreign debris inside the 2.5-m thick concrete block. Air leakage was checked with a pressure of 0.25 psig of nitrogen gas, and a maximum VSWR of 1.196 was obtained by measuring the vector reflection coefficients with the quarter-wave transmission section. In this paper, the design and the fabrication of the HPRF transmission line into the PEFP linac tunnel are presented.

Development of the integrated control system for the microwave ion source of the PEFP 100-MeV proton accelerator

The Proton Engineering Frontier Project (PEFP) 20-MeV proton linear accelerator is currently operating at the Korea Atomic Energy Research Institute (KAERI). The ion source of the 100-MeV proton linac needs at least a 100-hour operation time. To meet the goal, we have developed a microwave ion source that uses no filament. For the ion source, a remote control system has been developed by using experimental physics and the industrial control system (EPICS) software framework. The control system consists of a versa module europa (VME) and EPICS-based embedded applications running on a VxWorks real-time operating system. The main purpose of the control system is to control and monitor the operational variables of the components remotely and to protect operators from radiation exposure and the components from critical problems during beam extraction. We successfully performed the operation test of the control system to confirm the degree of safety during the hardware performance.

The proton engineering frontier project: Applications of accelerator technology

Launched in 2002 as a major national R&D project of Korea, the Proton Engineering Frontier Project is now being successfully completed in 2012 with three primary objectives. The first main goal is to develop a high-power 100-MeV, 20-mA proton linac, the second is to promote R&D programs by utilizing proton beams, and the third is to apply accelerator technology to industrial applications. This report mainly discusses progresses in the applications of accelerator technologies. Developments of low energy ion accelerators, by utilizing accelerator technologies, and challenging R&D activities, by using ion beams provided by those ion implanters and ion irradiators, are presented.

Development and evaluation of satellite image data analysis infrastructure

Tokyo University of Information Sciences (TUIS) receives moderate resolution imaging spectroradiometer (MODIS) data, and provides the processed data to universities and research institutes as part of the academic frontier project. One of the major fields of research using MODIS data is the analysis of changes in the environment. We are currently developing applications to analyze environmental changes. These applications run on our satellite image data analysis system, which is implemented in a parallel distributed system and a database server. When using satellite data, one common problem is the interference of clouds. In order to remove this interference, the standard solution is to create composite data of the same regions during a selected time span, and to patch together data which are not covered by clouds to create a clear image. We introduced a piece-processing algorithm which separates one set of satellite image data into many small pieces of image data, making it quicker and easier to analyze and process the time-series satellite data. In this research, we implemented the pieceprocessing and composite-processing algorithms in order to increase the speed of analysis within the satellite image database. We tested the proposed processing and verified its effectiveness for target applications.

C311001 東北大学グローバルCOEプログラム : 「流動ダイナミクス知の融合教育研究世界拠点」の教育研究成果

Activities and accomplishments of Tohoku University Global COE Program " World Center of Education and Research for Trans-disciplinary Flow Dynamics"(the GCOE) are discussed.The GCOE operates large numbers of conferences,workshops,summer schools and various student promotional programs to educate and cultivate graduate students and young researchers to become world competent leaders in their respective field in future.Member researchers of the GCOE publish 300 or more academic papers a year in flow dynamics.They have started in 2009 five GCOE Fusion Frontier Projects,in which researchers in different fields collaborate together for producing solutions to long awaited complicated problems.

A Data Envelopment Analysis Approach to Supply Chain Efficiency

Supply chain management is an important competitive strategies used by modern enterprises. Effective design and management of supply chains assists in the production and delivery of a variety of products at low costs, high quality, and short lead times. Recently, data envelopment analysis (DEA) has been extended to examine the efficiency of supply chain operations. Due to the existence of intermediate measures, the usual procedure of adjusting the inputs or outputs, as in the standard DEA approach, does not necessarily yield a frontier projection. The current paper develops a DEA model for measuring the performance of suppliers and manufacturers in supply chain operations. Additive efficiency decomposition for suppliers and manufacturers in supply chain operations is proposed.

Current Activities in the Korean Accelerator Community

Since 1988 when Pohang Light Source (PLS) started its construction, the Korean accelerator community has grown very fast and has expanded from electrons to protons and to rare isotopes. At this moment, there are four major activities: the Proton Engineering Frontier Project (PEFP) in Gyeongju, the Korea Rare Isotope Accelerator (KoRIA), the PLS-II, which is an upgrade of the current PLS, and the X-ray Free Electron Laser (XFEL). Besides these major activities, there are several industrial accelerators and medical ones. In this report, the details of these activities are summarized.

Initial Feasibility Study to Drill and Core the Ocean Mantle

An initial feasibility study (Pilisi and Whitney, 2011) of drilling through the Mohorovi i discontinuity (Moho) into the oceanic mantle specifically focused on future requirements for planning, drilling and coring a hole 500 m into the oceanic mantle from three candidate locations in the Pacific Ocean (Cocos Plate, Baja California, and offshore Hawaii). The study points out some of the critical issues that need to be resolved before embarking upon such a challenging project. It was conducted on the basis of data provided by the Integrated Ocean Drilling Program–Management International (IODP-MI), the Center for Deep Earth Exploration (CDEX) operating the drilling vessel Chikyu within IODP, public domain information, and past experience that Blade Energy Partners (hereafter mentioned as “Blade”; http://www.blade-energy.com/) has had with frontier projects in the offshore deepwater oil and gas and geothermal industries.

Uniform Irradiation in a PEFP 100-MeV Beam Line with Octupole Magnets

One of the PEFP (Proton Engineering Frontier Project) 100-MeV beam lines requires a large and uniform irradiation field of ±10% uniformity in the target area of 300 mm ◊ 300 mm. We studied the nonlinear optics method by using two octupole magnets in order to achieve a large uniform field at the target. We found that the particles can be uniformly distributed within ±10% in a 300 mm ◊ 300 mm irradiation field at the target. We also studied the conditions of the quadrupole and the octupole magnets to meet the requirement of a large and uniform irradiation field.

Design and Measurement of the RF Properties of a 13 MHz Cavity for the RF Implanter

A 13 MHz Radio Frequency (RF) cavity for an RF implanter has been designed and fabricated at the Proton Engineering Frontier Project (PEFP). It consists of a coil having a circular cross-section, accelerating electrodes that are directly coupled to the beginning and the end of the coil, and a ground electrode for the inductor. The purpose of this paper is to explain the design concept and the measurement results for the RF properties of this cavity. A resonant frequency of 12.69 MHz with critical coupling and an unloaded quality factor of 1066 were achieved, agreeing well with the simulation results. The field distribution in the cavity was measured by using the bead-pull method. The field flatness is 6.5%, which satisfies the control requirements for the field in the cavity.

The Proton Engineering Frontier Project: Beam Utilization and User Program

The Proton Engineering Frontier Project: Beam Utilization and User Program

EPICS-Based Software Development of a Low-level RF System for the PEFP 100-MeV Proton Accelerator

Since its launch in 2002, the Proton Engineering Frontier Project (PEFP) has been constructing a 100-MeV proton accelerator. The high-power radio-frequency (RF) signal should be delivered into the radio-frequency quadrupole (RFQ) cavities and drift-tube linac (DTL) tanks for stable and efficient acceleration of a proton beam. The RF amplitude and phase-stability requirements of the accelerating field of a low-level RF (LLRF) system are within ±1% and ±1◦, respectively. In order to achieve a better performance with specially developed software, we developed a remote control system for RF control with experimental physics and industrial control system (EPICS). The LLRF control system was developed with a versa-module eurocard (VME) single board computer (SBC) and a field-programmable gate array (FPGA) peripheral component interconnect (PCI) mezzanine card (PMC) extended board. The EPICS input output controller (IOC) was implemented with an embedded system that could make it easily accessible to operators when using the EPICS standard communication method. The LLRF IOC has been in use at the PEFP 20-MeV proton accelerator for five months. In this paper, the details of the implementation and the configurations will be described.

Beam Phase Measurement of the PEFP 20-MeV Proton Accelerator

A 20-MeV proton accelerator has been developed and tested at the Korea Atomic Energy Institute (KAERI) by the Proton Engineering Frontier Project (PEFP). Beam phase was measured at the end of the 20-MeV accelerator by using the beam position monitor (BPM) signal. The beam current and phase were measured by changing the relative RF phase between the 3-MeV radio frequency quadrupole (RFQ) and the 20-MeV drift; tube linac (DTL), and the results were compared with those simulated by using the PARMILA code. In tins paper, the beam phase measurement results are presented, and the phase scan results based on the normal operating condition are compared with the simulation results.

Strategies Contents for Financial Independent RIS in Proton Accelerator Science and Technology

This research would be the first step toward in the long processes of proton technology industrial cluster development by focusing on the region's readiness and acceptability of the proton technology project. As is shown in our questionnaire survey, the top priorities needed to consider for the Proton Technology project are found to be job creation (mean 3.74), regional economic development (mean 3.72), industry infrastructure(3.54), institution for science and education(3.53), economic inequalities(3.33), tourism industry revitalization(3.20). For public servants top priorities in order found to be regional economic development, job creation, industry infrastructure, institution for science and education, economic inequalities, tourism industry revitalization. Universities' priorities in order found to be job creation, regional economic development, institution for science and education, industry infrastructure, economic inequalities, tourism industry revitalization. The mean reliability score for the each party was found to be mayor((3.04), citizens(2.99), province(2.97), private corporation(2.96), and universities((2.93). Of particular note, the mean score except the mayor were all below median (3.00). province(3.24), city council member(3.20), public employees (3.09), private corporation(3.03), nonprofit organization (2.97), mass media (2.96), citizens(2.96), and universities(2.89). The universities and colleges also should revise their strategic plans and thus restructure their internal academic programs, and must develop their own collaborative programs with Proton Engineering Frontier Project, related industries, city, and other government units. Not only educating, training, and providing top-notched man powers to the proton technology industries will be one of their primary missions.

A coaxial HOM coupler for a superconducting RF cavity and its low-power measurement results

A resonant buildup of beam-induced fields in a superconducting radio frequency (RF) cavity may make a beam unstable or a superconducting RF cavity quench. Higher-order mode (HOM) couplers are used for damping higher-order modes to avoid such a resonant buildup. A coaxial HOM coupler based on the TTF (TESLA Test Facility) HOM coupler has been designed for the superconducting RF cavities at the Proton Engineering Frontier Project (PEFP) in order to overcome notch frequency shift and feed-through tip melting issues. In order to confirm the HOM coupler design and finalize its structural dimensions, two prototype HOM couplers have been fabricated and tested. Low-power testing and measurement of the HOM couplers has shown that the HOM coupler has good filter properties and can fully meet the damping requirements of the PEFP low-beta superconducting RF linac.

NewSolanumSpecies from Tanzanian Coastal Forests May Already be Extinct

ABSTRACT The genus Solanum represents a significant gap in our knowledge of the East African flora. The coastal forests of Tanzania are understudied and vulnerable due to habitat loss, and the Ruvu Catchment Forest Reserve in the Morogoro District was not botanically explored prior to the Tanzania Frontier Project in the 1990s. We describe a new Tanzanian endemic species, Solanum ruvu sp. nov., which is known from only one collection. The unusually long inflorescences with a dense covering of long straight prickles on the rachis distinguish S. ruvu from all other African species of spiny Solanum. Its likely affinities lie with another coastal forest species, S. zanzibarense, which exhibits a similar scandent habit, subentire leaves, thin stems, and prickles that are sometimes straight. The Ruvu Forest area is now increasingly populated and planted with rice and sesame. The relict natural vegetation is restricted to small areas of limestone outcrops unsuitable for agriculture and there is no forest canopy ...

Design Study on Slow Beam Extraction in the 1 GeV Rapid Cycling Synchrotron at the PEFP

in a slow extraction system for a future 1-GeV proton synchrotron the Proton Engineering Frontier Project. This paper describes the properties of the optics design and optimizations for slow extraction in the synchrotron. The eects of the thirdinteger resonance in Rapid Cycle Synchrotron were investigated. We performed beam tracking simulations to observe the motions of particles in phase space by using the Methodical Accelerator Design 8 program. Finally, we performed beam trace simulations at the designed slow extraction line and showed that the proton beam could be stably extracted by using the RCS.

? Beam Emittance Measurement and Simulation of the PEFP Front End Accelerator

A 20-MeV proton accelerator has been developed and tested at the Korea Atomic Energy Institute (KAERI) by the Proton Engineering Frontier Project (PEFP). It consists of a 50-keV proton injector, a 3-MeV radio frequency quadrupole (RFQ), and a 20-MeV drift tube linac (DTL). The beam emttance was measured at the middle point between two solenoids of the proton injector. Based on the measured data, the beam properties through the proton injector were simulated using the T-step code for various operating conditions. Also, the transmission ratio through the RFQ was calculated using the output data obtained from the T-step code. In this paper, the emittance measurement results are presented, and the simulation results based on the measurement data are discussed.

Beam Collimation in PEFP RCS

This work is related with the beam collimation in the injection period of the proton engineering frontier project (PEFP) rapid cycling synchrotron (RCS).The two-stage collimation scheme was used with two rectangular collimators. We studied the collimation efficiency in various collimator conditions and optimized the collimation systemin order to minimize the uncontrolled beam losses.

Phase Stability in the RF Reference System for the PEFP 100MeV LLRF Control System

The 100-MeV proton linear accelerator of the Proton Engineering Frontier Project (PEFP) has been developed and consists of a 3-MeV radio frequency quadrupole accelerator (RFQ), a 20-MeV drift tube linac (DTL), a medium energy beam transmitter (MEBT), and 100-MeV DTL tanks. The error of the accelerating field in the cavity should be within ±1◦ in phase and ±1% in amplitude, and the phase difference between adjacent cavities should be maintained continuously. To satisfy these requirements, high phase stability is required in the RF reference system for the PEFP lowlevel radio frequency (LLRF) control system. The RF reference system for the PEFP 100-MeV accelerator, which is composed of a local oscillator (LO), a rigid coaxial reference line of about 80-m length, Heliax cables, and LLRF analog components, was designed and its phase stability was evaluated. The reference signal was chosen to be the 300 MHz LO signal for phase stability of the LLRF control system. The phase noise of the local oscillator was measured and calculated as a phase error of 0.058 degrees. In the entire length of the RF reference distribution line, a phase stability of ±0.05 degrees was evaluated for a temperature change of ±0.1 ◦C. The phase stability of the LLRF analog system for up/down-conversion was also measured and depended on the temperature stabilization.