189,468 research outputs found
Fiscal Stabilisation Policy and Fiscal Institutions
No full textIn this paper we analyse countercyclical fiscal policy within the context of a microfounded analysis of business cycle stabilisation. We show that tax and spending instruments can have a useful counter cyclical role, even after allowing for the distortionary nature of the instruments and the need for debt sustainability. A critical barrier to the use of fiscal instruments may be political economy concerns, and we survey recent suggestions involving alternative fiscal policy institutions.
Fairy-wren parasitism vs group size - Serendip Sanctuary
No full text<p>Fairy-wren nests at Serendip Sanctuary, showing the territory ID, the cuckoo ID, whether the nest was parasitized, the fairy-wren group size and the year.</p
Transport scheduling by computer
No full textThis thesis describes the design of heuristics and of mathematical tools to solve
scheduling problems, and the successful application of the resultant computer
software to real life situations, principally in the public transport industry.The work started in 1960 and led, in 1963, to the world's first implemented rail
locomotive schedule produced by computer. Subsequently, most of the research
was undertaken in conjunction with the bus industry. A range of heuristic
methods for scheduling the vehicles was developed. During the 1970's these
methods were applied by the candidate to about fifteen bus companies, resulting
in substantial operational savings. Later, the software was further developed,
and installed for about thirty different bus and rail organisations.Driver scheduling, which is more complicated, was based first on heuristics, but
later on an integer linear programming model whose constraint and variable sets
were reduced to tractable size by a series of especially designed heuristics. Most
of the organisations which use the vehicle scheduling programs also use the
driver scheduling system, which was first installed, in 1984, for London
Transport.The success of the research is due both to its scientific content and to the
candidate's endeavours to prepare the transport industry for the use of
computers in scheduling. Several papers presented here were part of this
preparation process, educating the industry about what could be achieved, and
presenting the results of individual exercises. Some feasibility studies in rail
scheduling are also presented.A number of papers deal with other studies carried out with the bus industry, for
example the use of simulation to determine the robustness of a schedule, and the
determination of fare scales.Related problems include the construction of routes for road freight vehicles, the
choice of sites for delivery depots, and the determination of sites and heights for
electricity pylons. Papers on these are included.Current research includes investigations into the use of knowledge based
systems and of genetic algorithms in attempts to improve the driver scheduling
processes. In conjunction with a German organisation, other work seeks to
combine the best parts of the candidate's work and that of the German team;
this has led to the production of extensve reports in German, which are given in
the appendix.LIST OF PUBLICATIONS SUBMITTED
BOOKS (COPIES BOUND IN THE APPENDIX):
[1] A. Wren (1969) Applications of computers to transport scheduling in the United Kingdom (77
pages). Morgantown, West Virginia University Engineering Experiment Station Bulletin 91. •
[2] A. Wren (1971) Computers in transport planning and operation (152 pages). London, Ian Allan. •
[3] A Wren (1971) Planirovaniya i sostavleniye graphikoye dlya gruzovykh avtomobilei, avtobusov i
brigad (30 pages). (English title: Scheduling lorries, buses and crews, translated into Russian.)
Soviet Ministry of Planning.REFEREED AND INVITED PAPERS BOUND IN THE MAIN THESIS:
[4] K. Wolfenden and A. Wren (1966) Locomotive scheduling by computer. Proc. British Joint
Computer Conference, London, WE Conference Publication no. 19, pp. 31 -37. •
[5] J.C. Ranyard and A. Wren (1967) The optimum arrangement of towers in an electric power
transmission line. Computer Journal, vol.10, pp. 157-161. •
[6] A. Wren (1968) Review of computer scheduling of buses and crews. Proc. Public Transport
Analysis Seminar, London, Planning and Transport Research and Computation, pp. 42 -47. •
[7] A. Wren (1972) Bus scheduling: an interactive computer method. Transportation Planning and
Technology, vol.1, pp. 115 -122. •
[8] A. Wren and A. Holliday (1972) Computer scheduling of vehicles from one or more depots to a
number of delivery points. OR Quarterly, vol.23, pp. 333 -344. •
[9] P.D. Manington and A. Wren (1975) Experiences with a bus scheduling algorithm which saves
vehicles. International Workshop on Urban Passenger Vehicle and Crew Scheduling, Chicago (25
pages). •
[10] B. Manington and A. Wren (1975) A general computer method for bus crew scheduling.
International Workshop on Urban Passenger Vehicle and Crew Scheduling, Chicago (49 pages). •
[11] M.E. Parker and A. Wren (1976) Computer models for scheduling buses and their crews.
Australian Road Research Forum, Adelaide (34 pages). •
[12] M.T.A. Megeed and A. Wren (1979) Two algorithms for constructing good routes for the vehicle
scheduling problem (in Arabic). Proc. Cairo University Institute of Statistical Studies and Research
Conference (30 pages). Submitted in appendix. •
[13] A. Wren (1981) A general review of the use of computers in scheduling buses and their crews. In
A. Wren (ed.) Computer scheduling of public transport, Amsterdam, North- Holland, pp. 3 -16. •
[14] A. Wren and B.M. Smith (1981) VAMPIRES and TASC: two successfully applied bus scheduling
programs. In A. Wren (ed.) Computer scheduling of public transport, Amsterdam, North -Holland,
pp. 97 -124. •
[15] A. Wren (1982) Operational planning with the aid of computers: scheduling. In T. Young and R.
Cresswell (eds.) The urban transport future, London and New York, The Construction Press, pp.
113 -119. •
[16] A. Wren (1982) Twenty -one years of transport scheduling by computer. Proc. Informatica nos
Transportes e Communicoes, Lisbon (30 pages). •
[17] A. Wren, B.M. Smith and A.J. Miller (1985) Complementary approaches to crew scheduling. In J.-
M. Rousseau (ed.) Computer scheduling of public transport - 2, Amsterdam, North- Holland, pp. 263-
278. •
[18]. T. Hartley and A. Wren (1985) Two complementary bus scheduling programs. In J. -M. Rousseau
(ed.) Computer scheduling of public transport - 2, Amsterdam, North- Holland, pp. 345 -369. •
[19] A. Wren (1987) Software for bus operations planning. In P. Bonsall and M. Bell (eds.)
Information technology applications in transport, NVU Science Press, Utrecht, pp. 211 -233. •
[20] A. Wren (1987) Vehicle and crew scheduling. In H. Keller (ed.) Heureke '87 - Optimierung in
Verkehr und Transport. Vorschungsgesellschaft fuer Strassen - und Verkehrswesen, Koeln, pp. 475-
496. •
[21] B.M. Smith and A. Wren (1988) A bus crew scheduling system using a set covering formulation.
Transportation Research, vol.22A, pp. 97 -108. •
[22] A. Wren and M.P. Chamberlain (1988) The development of MICRO -BUSMAN; scheduling on
micro -computers. In J.R. Daduna and A. Wren (eds.) Computer -aided transit scheduling, Berlin,
Springer -Verlag, pp. 160 -174. •
[23] A. Wren and B.M. Smith (1988) Experiences with a crew scheduling system based on set covering.
In J.R. Daduna and A. Wren (eds.) Computer -aided transit scheduling, Berlin, Springer -Verlag, pp.
104 -118. •
[24] D.O. Wren and A. Wren (1990) Genetics, structures and types - an application to scheduling.
University of Leeds School of Computer Studies Report 90.23. •
[25] A. Wren (1991) The European CASSIOPE project: effective data management for public transport.
Proc. 22nd Annual Public Transport Symposium, University of Newcastle upon Tyne. •
[26] A. Wren and P. Beecken (1992) Towards a European standard for scheduling. To appear in M.
Desrochers and J. -M. Rousseau (eds.) Computer -aided transit scheduling - 2, Berlin, Springer -Verlag. •
[27] M. Chamberlain and A. Wren (1992) Developments and recent experience with BUSMAN and
BUSMAN II. To appear in M. Desrochers and J. -M. Rousseau (eds.) Computer-aided transit
scheduling - 2, Berlin, Springer-Verlag. •
[28] R.S.K. Kwan, A. Wren and L. Zhao (1992) Driver scheduling using intelligent estimation techniques
with heuristic searches. To appear in M. Desrochers and J. M. Rousseau (eds.) Computer-aided
transit scheduling - 2, Berlin, Springer -Verlag. Also appears as University of Leeds School of
Computer Studies Report 90.17 (1990). •
[29] A. Wren and D.O. Wren (1992) A genetic algorithm for public transport driver scheduling.
Submitted to Computers and Operations Research.
Research reviews and reports bound in the thesis •
[30] A. Wren (1969) Compilation of bus and crew schedules in the UK; the objectives, achievements and
prospects. Presented at the first Annual Seminar on Public Transport Operations Research,
University of Leeds (single page summary). •
[31] A. Wren (1970) Congestion and bus operation; report on a pilot study of bus services operated by
York -West Yorkshire Joint Services. University of Leeds Operational Research Unit report ULORU-
2 (19 pages). •
[32] A. Wren (1971) A computer bus scheduling exercise; a report to the Yorkshire Traction Co. Ltd.
University of Leeds Operational Research Unit report ULORU-4 (11 pages). •
[33] B. Manington and A. Wren (1971) The VAMPIRES bus scheduling program. Proc. Third Annual
Seminar on Public Transport Operations Research, University of Leeds (8 pages). •
[34] A. Wren (1972) Bus scheduling by computer; second report to the Yorkshire Traction Company
Limited. University of Leeds Operational Research Unit report ULORU -6 (16 pages). •
[35] A. Wren (1972) A depot location problem for Harris Road Services Ltd. University of Leeds
Operational Research Unit report ULORU-7 (5 pages). •
[36] A. Weaver and A. Wren (1972) Bus crew scheduling by computer, interim report no. 2. University
of Leeds Centre for Computer Studies report (8 pages). •
[37] L. Marsh and A. Wren (1972) The VAMPIRES bus scheduling program. Proc. Fourth Annual
Seminar on Public Transport Operations Research, University of Leeds (4 pages). •
[38] A. Wren (1972) The VAMPIRES bus scheduling program; report to Edinburgh Corporation
Transport. University of Leeds Operational Research Unit report ULORU -8 (8 pages). •
[39] H.S. Jackson and A. Wren (1973) Simulation of urban bus operations. Universities' Transport
Studies Group conference, London (17 pages). •
[40] A. Wren (1973) Simulation - a tool for bus operations planning. Proc. Fifth Annual Seminar on
Public Transport Operations Research, University of Leeds (12 pages). •
[41] A. Wren (1974) Computer scheduling of buses and crews - a review. Proc. Sixth Annual Seminar
on Public Transport Operations Research, University of Leeds (17 pages). •
[42] A. Wren (1975) Operational Research in the bus industry. Proc. Seventh Annual Seminar on Public
Transport Operations Research, University of Leeds (9 pages). •
[43] P.D. Manington, L.G. Proll and A. Wren (1975) The TRAVELLER vehicle routeing program
applied to deliveries of frozen foods to branches of Marks and Spencer; a pilot study undertaken for
Christian Salvesen (Cold Storage) Ltd. University of Leeds Operational Research Unit report
ULORU -13 (9 pages). •
[44] A. Wren (1975) Scheduling by computer - buses and crews; a report on a pilot study undertaken for
London Transport. University of Leeds Operational Research Unit report ULORU -15 (15 pages). •
[45] A. Wren (1975) Bus crew scheduling by computer; a pilot study for Greater Manchester Transport.
University of Leeds Operational Research Unit report ULORU -17 (10 pages). •
[46] A. Wren (1976) Bus crew scheduling by computer; a report on a pilot study undertaken for Coras
Iompair Eireann, Dublin City Services. University of Leeds Operational Research Unit report
ULORU -20 (16 pages). •
[47] H.J. Bransby, M.E. Parker and A. Wren (1976) Computer models for scheduling buses and their
crews. Proc. Eighth Annual Seminar on Public Transport Operations Research, University of Leeds
(15 pages). •
[48] L.G. Proll and A. Wren (1976) Calculations of a new fare scale. Proc. Eighth Annual Seminar on
Public Transport Operations Research, University of Leeds (15 pages). •
[49] A. Wren (1977) Ten years of computer scheduling. Proc. Ninth Annual Seminar on Public
Transport Operations Research, University of Leeds (9 pages). •
[50] A. Wren (1978) Basic algorithms for transport scheduling (BATS); a report to the West Yorkshire
Passenger Transport Executive. University of Leeds Operational Research Unit report ULORU -25
(11 pages). •
[51] A. Wren (1979) A practical bus scheduling exercise. Paper presented to the Universities' Transport
Studies Group (20 pages). •
[52] A. Wren (1979) Timetable and schedule compilation (TASC). University of Leeds Operational
Research Unit report ULORU -28 (56 pages). •
[53] M.E. Parker and A. Wren (1979) Crew and vehicle scheduling methods. Presented at the Public
Transport Reseearch and Computation course on Public Transport Analysis, London and issued as
University of Leeds Operational Research Unit report ULORU -30 (15 pages). •
[54] A. Wren (1979) Computer production of bus timetables. Proc. Eleventh Annual Seminar on Public
Transport Operations Research, University of Leeds (20 pages). •
[55] M.E. Parker and A. Wren (1981) Bus crew scheduling; a review of some union agreements
operating withing England, Scotland and Wales. Univeristy of Leeds, Department of Computer
Studies Report 144 (25 pages) •
[56] A. Wren and B.M. Smith (1981) Computer scheduling in Europe, and recent work in Leeds. Proc.
Thirteenth Annual Seminar on Public Transport Operations Research, University of Leeds (14 pages). •
[57] A. Wren and T. Hartley (1982) TASC: the benefits of a simple bus scheduling program. Proc.
Fourteenth Annual Seminar on Public Transport Operations Research, University of Leeds (27 pages). •
[58] B.M. Smith and A. Wren (1982) VAMPIRES in Dundee - a new look at a proven bus scheduling
system. Proc. Fourteenth Annual Seminar on Public Transport Operations Research, University of
Leeds (20 pages). •
[59] R.H. Williamson and A. Wren (1982) Implementation of the BUSMAN bus scheduling system.
EURO -V, Lausanne (27 pages). •
[60] A. Wren (1982) Mathematics, heuristics, pragmatics - a full circle? at the 25 Years of
Computing conference, University of Leeds Department of Computer Studies (12 pages). •
[61] M.E. Parker and A. Wren (1983) Costs of different bus crew scheduling constraints and levels of
service (34 pages). •
[62] A. Wren (1983) Computer scheduling of buses and crews. paper presented to the Chartered
Institute of Transport (23 pages). •
[63] B.M. Smith and A. Wren (1984) Computer scheduling using the BUSMAN programs. Proc.
Sixteenth Annual Seminar on Public Transport Operations Research, University of Leeds (9 pages). •
[64] A. Wren, E. Foster and T. Hartley (1985) Scheduling using microcomputers. Proc. Seventeenth
Annual Seminar on Public Transport Operations Research, University of Leeds (16 pages). •
[65] A. Wren (1985) Recent developments and applications of computer scheduling. Proc.
Seventeenth Annual Seminar on Public Transport Operations Research, University of Leeds (16
pages). •
[66] R.S.K. Kwan, A. Wren and B.M. Smith (1988). An expert system for bus crew scheduling.
University of Leeds School of Computer Studies report 88.14 (13 pages). •
[67] A. Wren, unattributed (1990) The state of the art in scheduling. In State of the art in computer -
aided technology in public transport. European Community DRIVE Programme V1019 (CASSIOPE)
project deliverable 1, pp. 10 -15, 81 -94. •
[68] CASSIOPE scheduling demonstration, written by A. Wren (1991) Report produced as delivarable
under the European Community DRIVE Programme V1019 (CASSIOPE), 17 pages.MAJOR REPORTS TO CLIENTS AND FOREIGN LANGUAGE REPORTS SUBMITTED IN THE APPENDIX:
[69] A. Wren (1985) on behalf of Wootton Jeffreys Consultants Ltd. Report to the Metropolitan Transit
Authority of Victoria on application of BUSMAN to rostering in the Rail Division (22 pages). •
[70] A. Wren (1987) on behalf of Wootton Jeffreys Consultants Ltd. Computer aided railway duty sheets.
Report to London Underground Ltd. (134 pages) •
[71] A. Wren (1991) Verbesserung des HOT Umlaufsoptimierungsalgorithmus. (Improvements to the
HOT bus scheduling algorithm.) (Report to the Hamburger Hochbahn AG, 30 pages.) •
[72] A. Wren (1991) Ein neuer Umlaufaenderungsdienst. (A new interactive amendment system for bus
schedules.) (Report to the Hamburger Hochbahn AG, 33 pages.) •
[73A] A. Wren (1992) Das HOT Dienstplansystem; das jetztige System, und Vorschlaege um
Verbesserung. (Description of the HOT crew scheduling system, with suggestions for improvement.)
(Report to the Hamburger Hochbahn AG, Part 1, 134 pages.) •
[73B] A. Wren (1992) Das HOT Dienstplansystem; das jetztige System, und Vorschlaege um
Verbesserung. (Description of the HOT crew scheduling system, with suggestions for improvement.)
(Report to the Hamburger Hochbahn AG, Part 2, 99 pages.) •
[74] A. Wren (1992) Wie ZIP mit HOT zu integrieren: das heuristische Dienstplansystem HOT durch
dem matematischen Algorithmus von BUSMAN verbessert. (How to integrate ZIP with HOT: the
improvement of the heuristic driver scheduling system HOT by means of the mathematical algorithm
of BUSMAN.) (Report to the Hamburger Hochbahn AG, 56 pages.
Fairy-wren parasitism vs group size - Campbell Park
No full text<p>Superb fairy-wren nests at Campbell Park showing the breeding female, whether the nest was parasitized by a cuckoo, which cuckoo territory the nest was within and the fairy-wren group size.</p
Kerry Downes, Christopher Wren, 1971
No full textBaridon Michel. Kerry Downes, Christopher Wren, 1971. In: Dix-huitième Siècle, n°5, 1973. Problèmes actuels de la recherche, sous la direction de Jacques Proust . p. 499
Sinaloa Wren subspecies distribution.
No full textOccurrence records for the distribution of the Sinaloa Wren retrieved from the Global Biodiversity Information Facility (GBIF 2020), used for ecological niche tests. Putative distribution for each subspecies is shown with different colors. (TIF)</p
Kerry Downes, Christopher Wren, 1971
No full textBaridon Michel. Kerry Downes, Christopher Wren, 1971. In: Dix-huitième Siècle, n°5, 1973. Problèmes actuels de la recherche, sous la direction de Jacques Proust . p. 499
Normalized frequency of contact pairs by contact duration (in minutes) on a log-log scale for contacts captured by WREN only and contacts captured by both WREN and Log.
No full textNormalized frequency of contact pairs by contact duration (in minutes) on a log-log scale for contacts captured by WREN only and contacts captured by both WREN and Log.</p
Extending the mutual information measure to rank inferred literature relationships-4
No full text<p><b>Copyright information:</b></p><p>Taken from "Extending the mutual information measure to rank inferred literature relationships"</p><p>BMC Bioinformatics 2004;5():145-145.</p><p>Published online 7 Oct 2004</p><p>PMCID:PMC526381.</p><p>Copyright © 2004 Wren; licensee BioMed Central Ltd.</p>rred relationships for the object "capsaicin
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