:SIGNAL97 Ver 1.02 15JAN00

Build 18 22FEB01

>Modeling for Special Case of Permitted Left Turn Corrected.

An obscure special case of the Single-Lane Approach permitted left turn model has been implemented, whereby if the opposing single-lane approach has a left turn volume of zero the calculated value of 'gdiff' is set to zero. Although occurence of this case is rare, when it does occur this new model will produce a different and more reasonble result, according to the methods of the HCM.

Build 16 12OCT00

>Lost Time Determination Fixed for Stem of T Intersection.

A common way of representing the lane usage on the stem of a T intersection is to have a through lane from which one or both turning movements turn. In particular, this is necessary if a single lane serves both turning movements. When determining the lost time for a lane group, SIGNAL97 looks to the phasing diagram to determine which phase terminates the lane group's green so that the Y time for that phase can be used in the HCM lost time equations. In this particular case, SIGNAL97 did not find the through movement for the through lane group in the phasing, because it did not exist, so the lost time was inadvertantly being set to zero. This condition has been corrected. This situation would only occur when a through lane was being used by turning vehicles, but not by any through vehicles.

>Export Updated to Incorporate New HCS Features.

HCS 3 has taken a step in the right direction in correcting its long-standing problem as to how actuated movements are represented, and this build of SIGNAL97 takes advantage of this change in representation. Previously, HCS has designated 'phases' as either fixed-time or actuated, whereas the HCM clearly indicates that the concern is whether a 'movement' is actuated or not. Now in HCS-3, individual movements are toggled as pre-timed or actuated, so SIGNA97 now uses this feature to set the actuated condition of each individual movement. The HCS is method is still not correct, in that an individual movement can be set actuated in one phase and pre-timed in another (which presents an undefined, impossible condition for the HCM method), but for purposes of data exported from SIGNAL97 this will not be a problem.

Another minor change in phasing export from SIGNAL97 is that if pedestrian volume levels are set to zero, pedestrians are not shown in the phasing diagram exported to HCS. This does not affect any analysis results, but make the phasing description appear more consistent with the analysis results. Previously, SIGNAL97 always created pedestrian movements in their associated through phases, regardless of the input pedestrian volume.

Build 14 26JUL00

>New Limits on Use of Sequence 8 Phasing.

When using DESIGN for phasing optimization, the new Sequence 8 phasing (Lead/Lag) introduced in SIGNAL97 will now be determined to be inappropriate if either of the two assocaited left turns does not exist or does not have opposing traffic. In these cases, other phasings will be clearly more appropriate, such as Sequence 1 (Single Phase) or Sequence 7 (Split Phase).

>Allowed Length of Data Path for HCS-3 Export Increased.

The allowed length of the path name for data files when Exporting to HCS-3 has been increased to its proper value of 64 characters. This limit was inadvertantly left at the debugging value of 16 when the first release of the Export function was made.

>EXPORT to Existing .HCS File Permitted.

EXPORTing to an .HCS file which already exists is now permitted. Previously, it was not possible to re-use an existing .HCS file without first deleting it.

>New Print Module for 32-bit Windows

A new TEAPAC print module (TEAPACPR.exe) has been created for 32-bit Windows platforms (Windows 95, Windows 98, Windows NT and Windows 2000) which has greater compatibility with some 32-bit printer drivers which have been distributed by printer vendors recently. This module also has continued compatibility with older printer drivers. The new module is now distributed as the standard print module for all Win32 versions of TEAPAC programs. The original print module is still distributed as the standard print module for all Win16 versions, and is also distributed as an alternate print module for the Win32 versions.

Build 12

>Improvements Made to HCS-3 Export.

Several improvements to the performance of the new HCS-3 Export function have been made. Export AUTO has been modified so that Windows NT is always able to find and run the HCS-3 program; if HCS-3 has been installed in a folder with spaces in the path name, the DOS version of SIGNAL97 will now locate and run HCS-3; and a missing file which is needed for Export under Windows has been included in the installation process.

Build 10

>Export to HCS-3 (Signals) Fully Supported.

SIGNAL97 now supports the Export function for all of the new data file formats, calling sequences, program names and installation changes for the new Windows version of HCS-3 (Signals Patch b and beyond). SIGNAL97 maintains continued support for the previous DOS version of HCS Signals (Ver 1 and 2) through use of the data file extensions for those versions, if needed. In the Export to HCS-2, the lane utilizations export has been corrected to use the inverted value from those input into SIGNAL97.

>New Input Values Displayed in Data Summary and Results.

Input values which are new for the 1997 HCM methodology in comparison to the SIGNAL94 inputs are now listed in the data summary produced by the View-Summary menu item or the SUMMARISE command. These include the inputs for STARTUPLOST, ENDGAIN and UPSTREAMVC. If unit extensions are input for ACTUATIONS entries, these values are now displayed properly. Also, the duration of the analysis period used in the analysis is displayed in the Level of Service Worksheet, and a few additional values for the protected-permitted left turn adjustment factor worksheet are zeroed out for Case 6 analyses so they all display as zero.

>Zero Overlap Time Allowed for Sequence 8 Analyses.

A sequence code 8 phasing (Lead-Lag) should permit zero time being allocated to the overlap phase as long as the other phases have non-zero time, since no vehicle sees this phase by itself. However, the initial release if SIGNAL97 objected to such timings unless they came directly from DESIGN via the DESIGN 1 entry. This condition has been fixed so that no objection is made to zero overlap time by the ANALYZE function, regardless of the source of the timings.

>Changes to Standard TEAPAC2000 Interface, Ver 4.01.

All TEAPAC programs which have Windows versions use the new TEAPAC2000 Interface which was introduced in November, 1999. The following changes have been made to this interface to further enhance its effectiveness:

>Spaces Allowed in Folder Names for Data Files.

Folders which contain data files may now contain spaces in the folder name. Data files themselves are still limited to 11 characters including the extension and may not have embedded spaces (for continued compatibility with supported DOS products), but the restriction on path names (folders) has been removed.

>File Name Can Be Inserted in Title Lines.

The name of the current open file can be inserted anywhere in a title line (PROJECT, DESCRIPTION or NOTE entry) by placing %F at the desired location of the title line. The file name can be placed at a specific column location in a title line by using the +XX form of a title entry (see Help for any of the title commands).

>Bigger Output Window for Higher Resolution Displays.

Output windows containing program results which are displayed at resolutions of 1024x768 or higher now use a larger window so that more results can be displayed and less scrolling is required to observe all of the results.

>Additional Help and Shortcut Features Added.

Several new help features have been added. One of these is a new Help button on the toolbar for direct access to the on-line manual. Help notes in the status line at the bottom of the window for each of the menu items in the File menu have also been added. The File-Close menu item in the main window now uses a shortcut of 'C' instead of 'L' for consistency with other programs, and the File-Exit menu item in the Results window has been changed to File-CloseResults to avoid confusion with the File-Exit menu item of the main window. Lastly, the last used file name is retained in the File-Open and File-SaveAs dialogs, even when a previous dialog was cancelled.

>New Warning Messages.

A new warning message has been generated to warn users if unsaved data values are about to be reset to default values by the File-New menu item. A new message also warns if the installed folder has spaces in its name, which will cause problems in certain operations like printing.

>Potential Problem Running Under Windows NT Eliminated.

In the initial release of the TEAPAC 2000 interface (07NOV99), a technique for dynamic menu building was used which had a conflict with certain service packs and memory configurations of Windows NT. To avoid this potential problem on any given machine, the dynamic menu building has been removed and replaced with a method that will work on all configurations of Windows NT.

:SIGNAL97 Ver 1.01 07NOV99

>WinSIGNAL97 Uses the New TEAPAC2000 Interface Version 4.00.

WinSIGNAL97 has been released with the new TEAPAC2000 Interface (Interface Version 4.00) which offers many new features to enhance the computing experience with TEAPAC programs. The following new features are among those provided by the TEAPAC2000 Interface:

-- Context-sensitive link to Help file for error messages.
-- Context-sensitive link to Help file for program outputs.
-- Modernized dialog box design consistent with Windows 95/98/NT.
-- New radio button and drop-down list input features.
-- Sizable main window for better screen display and integration with other running programs.
-- New Toolbar buttons for common functions.
-- File name and save status displayed in main window caption.
-- Help strings for menu options.
-- Dynamic title display during batch control file execution.
-- New accelerator keys (shortcuts) for common menu selections.
-- New File-Close menu option.
-- Sizable File-Open dialog.
-- Proportional scroll button for viewing output.

Other useful and unique features carried over from the previous Windows interface for TEAPAC include:

-- Visual Mode of input that shows graphically what inputs are needed.
-- Optional Manual Mode of input for blazing fast input by power users.
-- Context-sensitive link to Help file for all Visual Mode inputs.
-- Complete, fully-indexed manual on-line as Help file.
-- Ability to create and run batch/script/macro-type control files.
-- Ability to drag a data or control file from Explorer to the running TEAPAC program.
-- Free program updates via Internet downloads.
-- Complete data file compatibility between old, new, DOS and Windows versions.
-- Complete Y2K compliance.

Updates for the new TEAPAC2000 Interface can be downloaded from the www.StrongConcepts.com internet web page at no charge for users who hold an up-to-date Windows license for SIGNAL97. These downloads are available to the general public, but will be rendered as demos for those who do not qualify for the free update.

>Steps/Cycle Range and Default Changed for New PRETRANSYT Option

The allowed range for the <Steps/Cycle> input on the SIMULATION command has been changed to -300..300 to accommodate similar changes which are now allowed by the PRETRANSYT program. The default value has also been changed to 300 for compatibility with the PRETRANSYT default. This change has no impact on SIGNAL97 results.

:SIGNAL97 Ver 1.00 27AUG98

>First Version of SIGNAL97 Hits the Street.

SIGNAL97 is the first piece of software available which implements the procedures of Chapter 9 of the 1997 update to the 1985 Highway Capacity Manual. Over two years in the making and based on its popular predecessor, SIGNAL94, SIGNAL97 was used by the TRB Capacity Committee to help fine tune the new 1997 methods, and particularly in validating the worked sample problems which appear in the publication. Going one major step further than the procedures of Chapter 9, SIGNAL97 also optimizes the phasings and timings of an intersection to produce the best possible capacity analysis, like SIGNAL94 has done previously.

>Special Notes for Prior Users of SIGNAL94.

For prior users of SIGNAL94, a special set of notes have been prepared to discuss some of the important differences between using SIGNAL94 and SIGNAL97, as well as how best to use SIGNAL94 data files with SIGNAL97. These notes appear in Appendix C of the new SIGNAL97 manual, and are highly recommended for prior users of SIGNAL94 before using SIGNAL97.

this page last updated October 01, 2005