Magnetic Field Measurement and Analysis of the CSNS/RCS Quadrupole Magnets
The China Spallation Neutron Source/rapid-cycling synchrotron (CSNS/RCS) quadrupole magnets excited by both dc current and 25 Hz ac biased dc current were tested and measured in the past two years. All the magnets had been installed in the tunnel by the end of December, 2015. The challenges of the field measurements included the measurement repeatability of the dc field and the time harmonic measurement of the dc+ac field. The paper will summarize the results of the dc field measurement and the dc+ac field measurement, the key techniques of the rotating coil fabrication and the measurement stability for the CSNS/RCS quadrupole magnets.
Status of CSNS Project
The China Spallation Neutron Source (CSNS) accelerator is designed to accelerate proton beam pulses to 1.6 GeV at 25 Hz repetition rate, striking a solid metal target to produce spallation neutrons. The accelerator provides a beam power of 100 kW on the target in the first phase and then 500 kW in the second phase by increasing the average beam intensity 5 times while raising the linac output energy. The project construction has been formally launched in 2011 and it is planned to complete the project in March 2018. It is one of the high intensity proton accelerator projects in the world and it imposes a great challenge to Chinese accelerator community. This presentation will cover the status and challenges of the CSNS project.
Communicative Competence: Theory and Classroom Practice
ABSTRACT Within the framework of viewing communicative competence as a prerequisite to linguistic competence, rather than vice versa, this paper considers the following: (1) the nature of communicative competence; (2) the implications of communicative competence for second language teaching; and (3) ways in which the teacher can begin to make a foreign language program more meaningful. Communicative competeuce is defined as what native speakers know which enables them to interact effectively with each other. Implications for the language teacher include: (T) the need for tests which measure the ability to use language; (2) the irrelevancy of sequencing surface features; (3) the need for emphasis on non-lizguistic aspects of communication; and (4) the need to re-examiLe attitudes toward students and language teaching. Practical suggestins for implementing communicative competence in the classroom include the use of spontaneous role-playing, discussions, games, radio, and the telephone. (AM)