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Australian Atomic Energy Commission Research Establishment Lucas Heights AAEC/PR46 Part I AUSTRALIAN ATOMIC ENERGY COMMISSION RESEARCH ESTABLISHMENT LUCAS HEIGHTS PROGRESS REPORT 1979 PART I December 1980 PREFACE The Research Establishment Progress Report 1s a technical report dealing with work done In the twelve month period ending September 30 each year. For convenience of readers, this Progress Report Is published In two parts. Part I contains reports from those Research Establishment Divisions whose work Is concerned largely with research; progress in the work of remaining Divisions and Departments, which is largely service oriented, is described in Part II. Each part contains its own overall contents sheet and each sub-division of each part, its individual contents list. Note that these sub-divisions are independently paginated. Wherever possible, the names of staff responsible for the work being reported are given. CONTENTS PART I Research Divisions Applied Mathematics and Computing Chemical Technology Engineering Research Environmental Science Instrumentation and Control Isotope Materials Physics ANNUAL REPORT OF APPLIED MATHEMATICS AND COMPUTING DIVISION OCTOBER 1978 - SEPTEMBER 1979 Division Chief - Or D.J. Richardson CONTENTS 1. INTRODUCTION AND SUMMARY 2. DIVISIONAL RESEARCH 3 2.1 Applied Mathematics Research 3 2.2 Distributed Computer Networks 3 2.3 Interactive Computing 7 2.4 Computer Operating System Design and Optimisation 8 3. POWER AND ENERGY PROJECTS 13 3.1 AUS Module POW3D 13 3.2 MINI and ICCG Computer Graphics 15 3.3 Neutron Spectrum Unfolding 15 4. NUCLEAR FUEL CYCLE PROJECT 16 4.1 Compressible Flow in a Rotating Cylinder 16 5. RESEARCH ESTABLISHMENT SITE MANAGEMENT 16 5.1 Computer Operation 16 5.2 Development of System Software 19 5.3 Computer Hardware 34 5.4 Site Information Services Support 35 5.5 Site Information Services Computer System 36 5.6 Site Health Survey 37 5.7 Head Office Support 37 6. CONFERENCES, COURSES AND MEETINGS 38 7. PUBLICATIONS 39 1. INTRODUCTION AND SUMMARY The Applied Mathematics and Computing Division provides a computing service, together with mathematical and programming advice and assistance, to all parts of the Commission. The Division also undertakes research and development into areas of computing and mathematical techniques which have relevance to the Commission's activities. The major event of the present period was the installation and commissioning of the new IBM3031-based central computing system. The system was installed in December 1978 and brought into production in January 1979 with a transitional MVT (multi-programming, with a ^ariable number of tasks) operating monitor, similar to the MVT system previously running on the IBM360/65 computer. The IBM360/65 system was phased out in January 1979. Conversion to the new IBM operating system, MVS (multiple .virtual .storage), is now under way. This conversion is a major undertaking and is expected to be completed early in 1980. Whereas major changes to the previous MVT operating system were necessary to incorporate the advanced interactive network concepts and facilities developed within the Division, the new MVS operating system recognises the need for well-defined system user interfaces, and provides a number of than. This has allowed the Division to adopt a policy that all system developments within the Division shall interface in a standard manner with the MVS operating system; so far no exception to this policy has been needed. The Division's computer network handling software has been completely re-designed and re-written for MVS, to maintain all of the present network facilities and to provide extensive new facilities. A new method for network I/O (input/output) access has been devised. The UNIX operating system, developed by Bell Laboratories in the United States for large DEC PDP11 computers2 has been used as a base from which to provide a wide range of interactive user facilities for both the PDP11/45 Graphics node and the Site Information Services (SIS) PDP11/34 computer. Access is also available to the Editorial and Publications Group for the preparation of technical documents (see Sections 2.4 and 5.5). An international symposium on language design and programming methodology held in September 1979 was organised by Division staff and sponsored jointly by the Commission and the University of New South Wales. This symposium attracted world-wide interest, with keynote speakers coming from Austria and the United States. The Pascal system, developed by this Division, continues to be widely sought after, both in Australia and overseas. Close to 200 copies of this system have now been distributed world-wide. The feasibility of the Interdisk project was demonstrated with IBM330 compatible disk drives, before their replacement by the newer, faster IBM3550 drives. Digital Equipment Corporation (DEC) has offered to donate their new LSI11/23 computer to the Division to enable this project to be completed with these drives. Research is being undertaken into the area of multiprocessor computing systems, using cheap micro-processors. Their use as fast, reliable personal computers, and as communications controllers, is being investigated. In the field of Applied Mathanatics, the three-dimensional diffusion theory code POW3D, developed by the Commission after joint Australia-UK discussions, is being extended to include kinetic cases. Graphics packages developed previously have been used to produce a short film illustrating convergence techniques. The research into gas transport in lung airways, which led to the award of a Churchill Fellowship to a Division member, has continued; and a composite model of such gas transport has been proposed. 2. DIVISIONAL RESEARCH 2.1 AppVled Mathematics Research Gas transport in lung airways [M.R. Davidson]* A discrete linear model of convection-diffusion in branching alveolar ducts has been described in earlier progress reports. A composite model of a uniform lung is formed by matching a linear model pathway through the branched network of the respiratory region onto a trumpet representation of the conducting airways. The trumpet represents the increase in total airway cross-section with distance into the lung. Taylor dispersion, enhanced mixing due to heart action, and isotropic volume changes during breathing are important factors included. Average alveolar levels agree extremely well with published data. However, mixing during expiration is very rapid so that for inert gases, no alveolar slope is predicted in the absence of regional differences. 2.2 Distributed Computer Networks Network software for MVS [D.J. Richardson] The computer network handling software has been redesigned and rewritten to interface with the IBM MVS operating system in a completely standard manner. In addition to all previous functions available under MVT, the following new interactive user (link task) functions are provided: (i) Link tasks may be nested to any desired depth (previously limited to two levels of nesting). , (ii) Link tasks may operate either in a single-group address space for simple relay functions, or in their own private address spaces. * All work attributed to Dr Davidson was undertaken in the first portion of the current period, before he took up his Churchill Fellowship (Ill) Dynamic allocation, the equivalent of batch job JCL (job control language), is available to the private address space link task user. When implementing the new network handler under MVS, considerable attention was paid to giving the fastest possible response time to interactive users. To achieve this, queues of ready address spaces and task control blocks were provided for private address space users, and a new access method, AELCOM, was devised. A novel feature of AELCOM is that all I/O operations required by interactive users are performed under the aegis of the main link task monitor, thus avoiding the need to fix individual user I/O buffer areas, as required by all other IBM-provided access methods. Unhindered paging and address space swapping by link task users may take place, greatly improving overall response time and system efficiency. In addition, the delayed busy function,* previously a major systan modification under MVT, is incorporated as a standard part of AELCOM, avoiding the need for any system change to MVS. The Interdisk project [J.M. Tobias, D.J. Richardson] The necessary hardware for the Interdisk project has been completed by P.J. Ellis of Instrumentation and Control Division. A substantial amount of time was spent debugging the interfaces, and the greater part of the system is now functional. A highlight of the project was that it provided the ability to operate the complete prototype successfully, albeit in a restricted mode, on the IBM360/65 disk units. The original goal of the project has now been realised, with the completion of a unit that could link a PDP11 to IBM3330 disk units. Modula is the latest language to be designed by Professor Nicklaus Wirth, inventor of the Pascal programming language. It is being used for software development of Interdisk. Modula is a high level language designed for real-time control computers, and borrows many features from Pascal. The University of York has implemented Modula under UNIX, with an interface to LSIlls and GT40s. Modula has been installed under UNIX at the Research Establishment and is being used for most of the Interdisk software. * The delayed busy function is the subject of a provisional patent application [Richardson, Cox]. Preliminary documentation describing the prototype of Interdisk has been prepared and submitted to DEC for evaluation. In the last part of the period, progress of the Interdisk project was somewhat hampered by the delay in the provision of a new LSI11/23 computer. This computer is being donated to the AAEC by DEC to enable Interdisk to communicate with the high speed 3850 disk controllers. Although the LSI11/23 was expected March 1979, it has still not arrived. It appears that there is a world-wide delay in the provision of these new computers, and very few, if any, have arrived in Australia.
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