All submissions should be done electronically via http://www.ees.elsevier.com/omega and all communications are via email.

General
Articles must be written in good English.
Submission of an article implies that the work described has not been published previously (except in the form of an abstract or as part of a published lecture or academic thesis), that it is not Under consideration for publication elsewhere, that its publication is approved by all Authors and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the Publisher.
Upon acceptance of an article, Authors will be asked to transfer copyright (for more information on copyright see http://authors.elsevier.com ). This transfer will ensure the widest possible dissemination of information. An email will be sent to the corresponding Author confirming Receipt of the manuscript. A form facilitating transfer of copyright will be provided.
If excerpts from other copyrighted works are included, the Author(s) must obtain written permission from the copyright owners and credit the source(s) in the article. Elsevier has preprinted forms for use by Authors in these cases: contact Elsevier's Rights Department, Oxford, UK: phone (+44) 1865 843830, fax (+44) 1865 853333, e-mail: permissions@elsevier.com. Requests may also be completed online via the Elsevier homepage ( http://www.elsevier.com/locate/permissions ).

Online submission to the journal prior to acceptance
Submission to this journal proceeds totally online. Use the following guidelines to prepare your article. Via www.ees.elsevier.com/omega you will be guided stepwise through the creation and uploading of the various files. The system automatically converts source files to a single Adobe Acrobat PDF version of the article, which is used in the peer-review process. Please note that even though manuscript source files are converted to PDF at submission for the review process, these source files are needed for further processing after acceptance. All correspondence, including notification of the Editor's decision and requests for revision, takes place by e-mail and via the Author's homepage, removing the need for a hard-copy paper trail.
The above represents a very brief outline of this form of submission. It can be advantageous to print this "Guide for Authors" section from the site for reference in the subsequent stages of article preparation. Should Authors be requested by the Editor to revise the text, the first revised version should be submitted within six months. After this period, the article will be regarded as a new submission.

Electronic format requirements for accepted articles

General points
We accept most word-processing formats, but Word, WordPerfect or LaTeX is preferred. Always keep a backup copy of the electronic file for reference and safety. Save your files using the Default extension of the program used.

Word processor documents
It is important that the file be saved in the native format of the word processor used. The text should be in single-column format. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. In particular, do not use the word options to justify text or to hyphenate words. However, do use bold face, italics, subscripts, superscripts etc. Do not embed .graphically designed. equations or tables, but prepare these using the word facility. When preparing tables, if you are using a table grid, use only one grid for each individual table and not a grid for each row. If no grid is used, use tabs, not spaces, to align columns. The electronic text should be prepared in a way very similar to that of conventional manuscripts (see also the Guide to Publishing with Elsevier: http://authors.elsevier.com ). Do not import the figures into the text file but, instead, indicate their approximate locations directly in the electronic text and on the manuscript. See also the section on Preparation of electronic illustrations.
To avoid unnecessary errors you are strongly advised to use the 'spellchecker' function of your word processor.

Presentation of manuscript
Please write your text in good English (American or British usage is accepted, but not a mixture of these). Italics are to be used for expressions of Latin origin, for example, in vivo, et al., per se. Use decimal points (not commas); use a comma for thousands (10,000 and above).

Language Polishing. Authors who require information about language editing and copyediting services pre- and post-submission, please visit http://www.elsevier.com/languagepolishing or contact authorsupport@elsevier.com for more information. Please note Elsevier neither endorses nor takes responsibility for any products, goods or services offered by outside vendors through our services or in any advertising. For more information please refer to our Terms & Conditions http://www.elsevier.com/termsandconditions .

Provide the following data on the title page (in the order given).
Title. Concise and informative. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible.
Author names and affiliations. Where the family name may be ambiguous (e.g., a double name), please indicate this clearly. Present the Authors. affiliation addresses (where the actual work was done) below the names. Indicate all affiliations with a lower-case superscript letter immediately after the Author.s name and in front of the appropriate address. Provide the full postal address of each affiliation, including the country name, and, if available, the e-mail address of each Author.
Corresponding Author. Clearly indicate who is willing to handle correspondence at all stages of refereeing and publication, also post-publication. Ensure that e-mail address and complete postal address are included.
Present/permanent address. If an Author has moved since the work described in the article was done, or was visiting at the time, a "Present address" (or "Permanent address") may be indicated as a footnote to that Author's name. The address at which the Author actually did the work must be retained as the main, affiliation address. Superscript Arabic numerals are used for such footnotes.
Abstract. A concise and factual abstract is required. The abstract should state briefly the purpose of the research, the principal results and major conclusions. A structured abstract is required. For this, a recent copy of the journal should be consulted. An abstract is often presented separate from the article, so it must be able to stand alone. References should therefore be avoided, but if essential, they must be cited in full, without reference to the reference list.
Keywords. Immediately after the abstract, provide a maximum of 5 keywords from the list below. These keywords will be used for indexing purposes.

Arrangement of the article
Subdivision of the article. Divide your article into clearly defined and numbered sections. Subsections should be numbered 1.1 (then 1.1.1, 1.1.2, .), 1.2, etc. (the abstract is not included in section numbering). Use this numbering also for internal cross-referencing: do not just refer to 'the text'. Any subsection may be given a brief heading. Each heading should appear on its own separate line.
Introduction. State the objectives of the work and provide an adequate background, avoiding a detailed literature survey or a summary of the results.
Experimental/Materials and methods. Provide sufficient detail to allow the work to be reproduced. Methods already published should be indicated by a reference: only relevant modifications should be described.
Theory and/or calculation. A Theory section should extend, not repeat, the background to the article already dealt with in the Introduction and lay the foundation for further work. In contrast, a Calculation section represents a practical development from a theoretical basis.
Results. Results should be clear and concise.
Discussion. This should explore the significance of the results of the work, not repeat them.
Conclusions. A short Conclusions section is to be presented.
Figure captions, tables, figures, schemes. Present these, in this order, at the end of the article. They are described in more detail below. If you are working with LaTeX and have such features embedded in the text, these can be left, but such embedding should not be done specifically for publishing purposes. Further, high-resolution graphics files must be provided separately (see Preparation of illustrations).

Specific remarks
Mathematical formulae. Present simple formulae in the line of normal text where possible. In principle, variables are to be presented in italics. Use the solidus (/) instead of a horizontal line, e.g., X _p/Y _m rather than
_m
p
Y
X
Powers of e are often more conveniently denoted by exp.
Number consecutively any equations that have to be displayed separate from the text (if referred to explicitly in the text).
Footnotes. Footnotes should be used sparingly. Number them consecutively throughout the article, using superscript Arabic numbers. Many word processors build footnotes into the text, and this feature may be used. Should this not be the case, indicate the position of footnotes in the text and present the footnotes themselves on a separate sheet at the end of the article. Do not include footnotes in the Reference list.
Table footnotes. Indicate each footnote in a table with a superscript lowercase letter.
Tables. Number tables consecutively in accordance with their appearance in the text. Place footnotes to tables below the table body and indicate them with superscript lowercase letters. Avoid vertical rules. Be sparing in the use of tables and ensure that the data presented in tables do not duplicate results described elsewhere in the article.

References
Citations in the text: Please ensure that every reference cited in the text is also present in the reference list (and vice versa). Any references cited in the abstract must be given in full. Unpublished results and personal communications are not recommended in the reference list, but may be mentioned in the text. If these references are included in the reference list they should follow the standard reference style of the journal and should include a substitution of the publication date with either 'Unpublished results' or 'Personal communication'. Citation of a reference as 'in press' implies that the item has been accepted for publication.
Text: Indicate references by number(s) in square brackets in line with the text. The actual Authors can be referred to, but the reference number(s) must always be given.
Example: ...... as demonstrated [3,6]. Barnaby and Jones [8] obtained a different result .....
List: Number the references (numbers in square brackets) in the list in the order in which they appear in the text.

Examples:
Reference to a journal publication: [1] Van der Geer J, Hanraads JAJ, Lupton RA. The art of writing a scientific article. J Sci Commun 2000; 163:51-9.
Reference to a book:
[2] Strunk Jr W, White EB. The Elements of Style, 3rd ed. New York: Macmillan; 1979.
Reference to a chapter in an edited book:
[3] Mettam GR, Adams LB. How to prepare an electronic version of your article. In: Jones BS, Smith RZ, editors. Introduction to the electronic age. New York: E-Publishing Inc; 1999, p. 281-304.

Preparation of electronic illustrations
Please make sure that artwork files are in an acceptable format (TIFF, EPS or MS Office files) and with the correct resolution. If, together with your accepted article, you submit usable colour figures then Elsevier will ensure, at no additional charge, that these figures will appear in colour on the Web (e.g., ScienceDirect and other sites) regardless of whether or not these illustrations are reproduced in colour in the printed version. For colour reproduction in print, you will receive information regarding the costs from Elsevier after receipt of your accepted article. Please indicate your reference for colour in print or on the Web only. For further information on the preparation of electronic artwork, please see: http://authors.elsevier.com/artwork .
Please note: Because of technical complications which can arise by converting colour figures to 'grey scale' (for the printed version should you not opt for colour in print) please submit in addition usable black and white versions of all the colour illustrations.
General points
• Make sure you use uniform lettering and sizing of your original artwork.
• Save text in illustrations as .graphics. or enclose the font.
• Only use the following fonts in your illustrations: Arial, Courier, Helvetica, Times, Symbol.
• Number the illustrations according to their sequence in the text.
• Use a logical naming convention for your artwork files.
• Provide all illustrations as separate files and as hardcopy printouts on separate sheets.
• Provide captions to illustrations separately.
• Produce images near to the desired size of the printed version.

Proofs
One set of page proofs in PDF format will be sent by e-mail to the corresponding Author and should be returned within 48 hours of receipt. Elsevier now sends PDF proofs which can be annotated; for this you will need to download Adobe Reader version 7 available free from http://www.adobe.com/products/acrobat/readstep2.html . Instructions on how to annotate PDF files will accompany the proofs. If you do not wish to use the PDF annotations function, you may list the corrections (including replies to the Query Form) and return to Elsevier in an e-mail. Please list your corrections quoting line number. If, for any reason, this is not possible, then mark the corrections and any other comments (including replies to the Query Form) on a printout of your proof and return by fax, or scan the pages and e-mail, or by post.
Please use this proof only for checking the typesetting, editing, completeness and correctness of the text, tables and figures. Significant changes to the article as accepted for publication will only be considered at this stage with permission from the Editor. We will do everything possible to get your article published quickly and accurately. Therefore, it is important to ensure that all of your corrections are sent back to us in one communication: please check carefully before replying, as inclusion of any subsequent corrections cannot be guaranteed. Proofreading is solely your responsibility. Note that Elsevier may proceed with the publication of your article if no response is received.

Electronic offprints (e-offprints)
The corresponding author will be provided with a PDF file of the article via e-mail. This PDF file is a watermarked version of the published article and includes a cover sheet with the journal cover image and a disclaimer outlining the terms and conditions of use.

Submission checklist
It is hoped that this list will be useful during the final checking of an article prior to sending it to the journal's Editor for review. Please consult this Guide for Authors for further details of any item.

Ensure that the following items are present:
• One Author designated as corresponding Author
• E-mail address
• Full postal address
• All necessary files have been uploaded
• Keywords
• All figure captions
• All tables (including title, description, footnotes)
Further considerations
• Manuscript has been .spell-checked.
• References are in the correct format for this journal
• All references mentioned in the Reference list are cited in the text, and vice versa
• Permission has been obtained for use of copyrighted material from other sources (including the Web)

Authors' rights
As an author you (or your employer or institution) may do the following:
- make copies (print or electronic) of the article for your own personal use, including for your own classroom teaching use
- make copies and distribute such copies (including through e-mail) of the article to research colleagues, for the personal use by such colleagues (but not commercially or systematically, e.g., via an e-mail list or list server)
- post a pre-print version of the article on Internet websites including electronic pre-print servers, and to retain indefinitely such version on such servers or sites
- post a revised personal version of the final text of the article (to reflect changes made in the peer review and editing process) on your personal or institutional website or server, with a link to the journal homepage (on elsevier.com)
- present the article at a meeting or conference and to distribute copies of the article to the delegates attending such a meeting
- for your employer, if the article is a "work for hire", made within the scope of your employment, your employer may use all or part of the information in the article for other intra-company use (e.g., training)
- retain patent and trademark rights and rights to any processes or procedure described in the article
- include the article in full or in part in a thesis or dissertation (provided that this is not to be published commercially)
- use the article or any part thereof in a printed compilation of your works, such as collected writings or lecture notes (subsequent to publication of your article in the journal)
- prepare other derivative works, to extend the article into book-length form, or to otherwise reuse portions or excerpts in other works, with full acknowledgement of its original publication in the journal

Keyword list

Accounting
Air transport
Allocation
AHP
Application
Artificial intelligence
Automobile industry
Banking
Bidding
Branch and bound
Business policy
Capacity analysis
Case study
Chance constraints
Combinational analysis
Computing
Containers
Cost benefit analysis
Cost models
Crew scheduling
Cutting stock problem
DEA
Decision making/process
Decision support systems
Deterministic demand
Dynamic programming
Econometrics
Education
Efficiency
Electricity supply
Energy
Environmental studies
Expert systems
Facility layout
Flexible manufacturing
Flow-shop
Forecasting
Forestry
Fractional programming
Fuzzy sets
Game theory
Geometric programming
Goal programming
Graph theory
Group decisions
Health service
Heuristics
History of OR
Information systems
Information theory
Integer programming
Inventory control
Job shop scheduling
Just-in-time
Knapsack
Learning
Line balancing
Location
LP
Maintenance
Management
Management of science/technology
Manufacturing
Marketing
Markov chain
Materials handling
Mathematical programming
MIS
Multicriteria
Newsboy problem
Nonlinear programming
Operational/OR
Operations management
Optimization
OR education
Philosophy of OR
Planning and control
Policy analysis
Portfolio selection
Probability
Product life cycle
Production
Production planning and control
Project management
Quadratic programming
Queuing
Rail transport
Reliability
Replacement
Resource management
Risk
Routing
Scheduling
Search procedure
Sensitivity analysis
Sequencing
Set covering
Simulation
Spanning tree
Sports
Statistics
Stochastic programming
Telecommunications
Time series
Timetabling
Traveling salesman
Value chain
Vehicle scheduling

For any further information please contact the Author Support Department at authorsupport@elsevier.com.