A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z    

Kang, H.-S.

 
Paper Title Page
TUZH102 Ion Instability Issues in Electron Rings 79
 
  • T.-Y. Lee, J. Choi, H.-S. Kang
    PAL, Pohang, Kyungbuk
 
  The fast ion instability (FII) attracts interests recently for the International Linear Collider Project. FII was found by simulation in SLAC and later observed experimentally. Brief introduction and history of FII is given in this talk and a recent observation of FII in the PLS in-vacuum undulator is reported.  
slides icon Slides
WEPMA075 Improvement of Web-Based Monitoring of EPICS-IOC for PAL Control System 428
 
  • J. M. Kim, K. M. Ha, H.-S. Kang, J. H. Kim, E.-H. Lee
    PAL, Pohang, Kyungbuk
 
  We are now operating a web-based monitoring system of PAL control system with MAC Power PC. In order to expand the IOC’s web-based monitoring system, we are trying to use the X86/Linux platform. With the experience which we got in developing the web-based monitoring of EPICS-IOC based on MAC Power PC, a web-based monitoring system with an X86 Intel PC based on a new concept has been developed for lower costs, easier access and use. Its operating system employs Linux Fedora Cor·104. In order to drive the web-based monitoring system, EPICS Base 3.14.8 and MySQL 4.0 have been installed in the Linux Fedora Core 4. Archive engine with C language and EPICS channel access library are programmed to store the data. As a result of using the web-based monitoring system based on the X86 Intel PC, we have achieved its easier access and use, more convenient maintenance. Performance of the web-based monitoring system with an X86 Intel PC will be discussed.  
WEPMA080 Control System for the Bending MPS at PLS Linac 437
 
  • J. H. Kim, J. Choi, K. M. Ha, J. Y. Huang, H.-S. Kang, J. M. Kim, S.-C. Kim, I. S. Ko
    PAL, Pohang, Kyungbuk
 
  The former control system of the bending MPS (Magnet Power Supply) has a three-layered architecture. It was developed by in-house members in early 1993. It is upgraded based on EPICS as the protocol for the full upgrade of the PLS control system. We have replaced the former VME 68K CPU boards with OS-9 to new Power CPU boards operated by VxWorks as IOC in the linac klystron gallery. The upgraded bending MPS control system consists of a MVME5100 EPICS IOC core in the lower level control. It is implemented with the MEDM tool of EPICS to provide friendly Graphical User Interfaces. This paper describes the VME IOC and OPI and embedded local controller in MPS cabinet used for the bending MPS control in the PLS linac

Pohang Accelerator Laboratory, Pohang, 790-784, KoreaThis works supported by the Ministry of Science and Technology, Korea.

 
WEPMA103 The Design And Performance of the Prototype Digital Feedback RF Control System For the PLS Storage Ring 464
 
  • I. H. Yu, J. Y. Huang, H.-S. Kang, D. T. Kim, H. Y. Kim, S.-C. Kim, I. S. Park
    PAL, Pohang, Kyungbuk
 
  The digital feedback RF control system for the Proton Engineering At the Pohang Light Source (PLS) Storage Ring, the low level RF system based on analog technique provides RF field control for the 4 RF stations, and each station drives each RF cavity at 500.082MHz. To achieve better control system stability and accuracy, the prototype digital feedback RF control has been developed in Pohang Accelerator Laboratory (PAL). In addition to RF field control, it provides cavity resonance control, and incorporates the personnel and machine protection functions. An accelerator electric field stability of ± 0.5% in amplitude and ± 0.5° in phase is required for the RF system. In order to accomplish these requirements, a digital feedback control technique is adopted for flexibility of the feedback and feed forward algorithm implementation. In this paper, the design and performance of this system will be presented with the performance test results.  
THPMA047 Stair Current Output Power Supply for Switching Magnet 691
 
  • S.-H. Jeong, J. Choi, H.-S. Kang, D. E. Kim, K.-H. Park
    PAL, Pohang, Kyungbuk
 
  The switching magnet for beam distribution to 5 beamlines of 20-MeV PEFP is served with DSP-controlled PWM switching-mode converter. This converter is employed IGBT module and a DSP (Digital Signal Processor) that is operated at ?350A, 2.5 Hz stair output. Current feedback and input voltage feed-forward control schemes are applied to improve the output current stability. Designed filter result in the good stability of each stair. Simulation and experimental results show that the implemented converter achieves stable repeat response at each stair and feasibility for versatile power supply.  
THPMA114 Activities on the Nuclear Data Measurement at the Pohang Neutron Facility Based on Electron Linac 800
 
  • G. N. Kim
    Kyungpook National University, Daegu
  • M.-H. Cho, I. S. Ko, W. Namkung
    POSTECH, Pohang, Kyungbuk
  • H.-S. Kang, Y. D. Oh
    PAL, Pohang, Kyungbuk
 
  We report the present status of the Pohang Neutron Facility which consists of an electron linear accelerator, a water-cooled Ta target, and a 12-m time-of-flight path. We measured the neutron total cross-sections in the neutron energy range from 0.1 eV to few hundreds eV by using the neutron time-of-flight method. A 6LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. The background level was determined by using notch-filters of Co, In, Ta, and Cd sheets. In order to reduce the gamma rays from Bremsstrahlung and those from neutron capture, we employed a neutron-gamma separation system based on their different pulse shapes. The present measurements of Ta, Hf, Ag, and Mo samples are in general agreement with the evaluated data in ENDF/B-VI. The resonance parameters were extracted from the transmission data from the SAMMY fitting and compared with the previous ones.