CORC

Abstract: A Conductor on Round Core (CORC®) cable wound with a high temperature superconductor is an important cable concept for high current density applications. The design of a CORC cable makes understanding its electromagnetic performance—for example its AC losses—challenging. This paper presents a thorough study of CORC cables by combining experimental and numerical methods. In particular, it focuses on understanding how the cable structure influences the magnetization losses and on how these can be reduced. A novelty of this paper lies in the use of a new T-A formulation, which, for the first time, is employed for three-dimensional modelling of a CORC cable with real geometry. The use of the new T-A formulation in finite element software enables the study of how the winding direction and multiple-layer structure affect the magnetization losses of CORC cables. Moreover, influence of striation in CORC cables is studied as an effective way to reduce their losses. A CORC cable with striated tapes shows a significant magnetization loss reduction at high magnetic fields, in comparison to its counterpart without striated tapes. At low magnetic fields, tape striation leads to an increase in loss when the number of filaments is low, then the loss drops with a further increase in the number of filaments, but this loss reduction is much weaker than that at high fields. This paper provides an efficient tool for investigating the electromagnetic behaviour of CORC cables, which can provide valuable guidance in designing CORC cables with minimized losses for high energy physics and energy conversion applications.

Abstract: Thin ReBCO tapes of 2 mm in width and only 30- $\mu$ m substrate thickness allow production of thin CORC wires of 3–4 mm in diameter. These CORC wires feature high bending flexibility and high current densities as required for high field magnets. Two CORC wires, the first with 50 tapes and the second with 29 tapes, were developed and tested in a common effort of CERN, ACT, and the University of Twente. The two CORC wires were tested as small solenoids in transverse magnetic fields of up to 10.5 T and at 4.2 K. Afterwards, single tapes were extracted from the samples and tested individually in self field at 76 K. The first CORC wire had a critical current of 4255 A and an engineering current density of 322 A/mm $^2$ , while the second wire showed 3970 A and 412 A/mm $^2$ , both at 10 T and 4.2 K. The extracted tape analyses showed points of improvement for both wires, and therefore, provide valuable feedback for improving the wire production process and wire handling. CORC wire optimization resulted in no performance degradation of the 29-tape wire during electromagnetic load cycling at high magnetic fields. In this paper, details are presented on the CORC wires and measurement results are summarized.

Abstract: Information technology (IT) encompassing an integrated library system, computer hardware and software, CD-ROM, Internet, and other domains, including MARC 21 formats, CORC, and metadata standards (Dublin Core, TEI, XML, RDF) has produced far-reaching changes in the job functions of catalogers. Libraries are now coming up with a new set of recruiting requirements for these positions. This paper aims to review job advertisements published in American Libraries (AL) and College and Research Libraries News (C&RL NEWS) to assess the impact of the use of IT in libraries on job requirements and qualifications for catalogers. ********** Three major developments in library automation and IT have brought sweeping changes in cataloging during the last four decades. The first was the development of the MARC format by the Library of Congress (LC) in the early 1960s. It formed the basis of library automation systems and led to the creation of bibliographic utilities in the 1970s, the use of which not only freed catalogers from clerical aspects of their duties, but also increased cataloging productivity. Professional catalogers were then able to concentrate on original cataloging and even took up difficult materials, such as theses and dissertations, technical reports, and nonbook materials, which they were unable to catalog before. The effect of bibliographic utilities on cataloging became evident in job advertisements in which experience with utility was either required or desired. Phrases like "experience with OCLC operations" and "familiarity with RLIN or similar systems" are listed as qualifications for catalogers and managers alike, revealing the impact of the new technology on practice and workflow from top to bottom. (1) The second important development, which took place in the early to mid 1980s was the introduction of microcomputer and optical disc technologies. Bibliographic utilities and vendors of MARC records started distributing records on CD-ROM, thus allowing even smaller libraries, which cannot afford expensive online access to OCLC and other utilities, to install CD-ROM-based bibliographic databases on local area networks for copy cataloging. The success of these CD-ROM databases encouraged the LC and other agencies responsible for developing and distributing various cataloging tools to issue them on CD-ROM. Catalogers found CDMARC (discontinued in 1997), CatCD, Classification Plus, Dewey for Windows, Cataloger's Desktop, and others easier to store and more up-to-date than the print version. However, to install and use these products effectively required catalogers to have knowledge of such topics as computing, desktop applications, and network-based tools. The job advertisements, therefore, required computer skills for catalog librarians, including knowledge of PC-based applications and bibliographic utilities as well as CD-ROM experience. The emergence of Internet technologies in the 1990s, markup languages, and non-MARC standards are the third group of developments that have impacted cataloging jobs. As a result, some cataloging positions now require proficiency with computer applications (Internet, integrated library system [ILS], e-mail, and PC software packages), knowledge of markup languages (HTML, SGML, and XML), and experience or familiarity with emerging metadata schemes and tools (Dublin Core, CORC, EAD, TEI, RDF). This paper aims to trace the impact of all these developments in library automation and IT on position titles, degree requirements, and required skills of catalogers by analyzing job advertisements published in C&RL News and AL over a two-year period (2000 and 2001). * Literature Review Several articles have appeared during the last ten years or more discussing the changing and evolving roles of catalogers and the impact of automation on job requirements and qualifications for catalogers. Furuta's study revealed that bibliographic utilities in the 1970s produced far-reaching changes in cataloging departments by allowing the bulk of the material to be processed more quickly and cost effectively by nonprofessionals. …

Abstract: CORC is an experimental computing language that was developed at Cornell University to serve the needs of a large and increasing group of computer users whose demands are both limited and intermittent. These are the laymen of the computing world, who chose to become as little concerned as possible in the computing process and mechanics, but who would like to benefit from the computational ability that is now commonplace. At a university most of the faculty and student users would fall into this category. In recognition of the current significance of the computer in every area of business, science and engineering there is increasing faculty interest in introducing some use of modern computation into the students' academic experience if this can be done without placing too great a burden on an already hard-pressed curriculum. But computing is not going to be widely used in mathematics and engineering courses if the mechanics of its use are a burden to either the teacher or the student, or if the time necessary to prepare, test and operate programs cuts significantly into the subject matter for which the course was intended. Some participation on the part of the student appears to be an academic virtue, as well as a practical economic necessity—we have never heard any university computing center expansionist, in his wildest moments, propose a completely closed shop programming-operating service for general undergraduate use. In their own research many of the faculty are in the same position as their students. They will use the computer if it is convenient to do so and if it does not involve a major diversion into a technical field which is essentially extraneous to the basic subject matter. The closed-shop computing service in which the professor has (in principle anyway) only to describe his problem to a professional is of course intended to serve this need but we believe it is axiomatic that no university computing center will ever be adequately staffed to