GHS Version Update History from Version 15.50 to 16.00


GHS Version Update History since Version 16.00

Version 16.00A

WAIT BReak was added to break out of macros and run files for keyboard command
entry, resuming control when the Esc key is pressed.  This is similar to WAIT
without BREAK, except commands can be entered while waiting and names of active
macros and non-persistent templates are displayed to help develop and debug
complicated run files.

GROUND /FLOOR now supports floor files with as few as four points surrounding
the vessel.

GROUND /FLOOR was trapping an error for single-point stations and locking the
floor file after "Invalid floor data" errors.

SEAkeeping was not correctly calculating the pitch hydrostatic stiffness
coefficient when the vessel's longitudinal center is not near zero.


Version 16.00B

FSMMT MAX [:Keep] subparameter was added to keep the present load instead of
changing it to the load having maximum free surface moment.

DISPLAY STATUS was incorrectly treating WAVE (SPECTRA) as a TROCHOID
wave instead of as OFF (requires updated CG.EXE).


Version 16.02

SEAkeeping /SUMmary:[Position] [Velocity] [Acceleration] parameter was added
to conclude the seakeeping report with the specified extreme response amplitude
summary tables (or all summaries if just /SUMMARY is present).

SEAkeeping /CONFidence:percent,hours parameter was added to allow computation
of extreme response amplitudes in irregular waves by specifying a confidence
percentage and time interval in hours.  The extreme amplitudes are computed
for all modes and added to the Response Statistics and any Summary tables.

SEAkeeping /GUnit parameter was added to allow accelerations to be returned
in "g" gravitational units instead of current length units.

SEAkeeping /DATA: REsponse subparameter was added to output a Comma-Separated
Values (CSV) data file RESPONSE.DAT recording RAOs, response amplitudes, and
phase angles for vessel CG and all critical points.

SEAkeeping Response Statistics tables now include average response periods
between zero-up-crossings and response peak values.

SEAkeeping updated the formatting of its Response Statistics tables to reflect
the addition of response periods and additional extreme response amplitudes.

SEAkeeping was not correctly computing derived critical point surge and sway
response position amplitudes when the VCG was significantly above or below
the waterline.

VIEW was sometimes omitting the first page header line after a plot and
hanging on lines longer than 4000 characters (requires updated GHSVIEW.EXE).

ENTER PM fitting of a centerline SHAPE into a non-centerline component
was sometimes doubling stations until the geometry is written and re-read
(requires updated PM.EXE).


Version 16.02A

PTYPE system variable was added to return the type of the current part in the
format shown by the bare TYPE command (empty if multiple parts are selected).

GROUND /FLOOR now traps an error when origin depth is undefined, just like
for non-seafloor ground points.


Version 16.04

RA /LIM was sometimes failing with undefined percentage of Deck Immersion
limit angle for asymmetric vessels having greater freeboard at 15 degrees heel
than when upright.

ENTER PM command SURFACE improved rendering visualization in many cases
(requires updated PM.EXE and SE.EXE).


Version 16.06

ADD and WEIGHT commands added /GYRadius:li,ti,vi[,tv,vl,lt] optional extra
parameters to specify signed product of inertia gyradii around its own CG axes.

STATUS PRoduct [:ALl|TOtal] [:OWn|POint] parameter was added to include
a table showing products of inertia around coupled axes, otherwise behaving
the same as the STATUS INERTIA parameter showing rotational inertia.

GYRADTV, GYRADVL, and GYRADLT system variables were added to return the
square roots of total products of inertia from all weights and tanks around the
indicated CG axes divided by total weight, preserving inertia sign.  Gyradius
variables are undefined unless all tanks are intact or frozen.

VARIABLE /LIST no longer lists time-consuming variables like GMT as undefined.

SOLVE does a better job snapping to 0 trim when valid to do so.

GROUND (n) *, bvar /ACCESS was not always setting bvar to the current buoyant
force of the nth ground point if SOLVE wasn't done after a waterplane change.

STATUS MOMENTS was failing to combine light ship items unless INERTIA
was also specified (since 15.38A only).

ENTER PM centerline paired boxes with positive INBOARD were sometimes
missing their final station when longitudinally close to the origin, affecting
(for example) symmetric rudders with aft origin (since 16.00 only; requires
updated PM.EXE).


Version 16.06A

SEAkeeping was trapping a run-time error for submerged sections with very
small maximum widths.


Version 16.08

MAXVCG was getting spurious UNDEF results in rare cases later in a list of
multiple displacements that would not have occurred running the displacement
by itself.

FSMMT MAX when trapping "Inappropriate tank" was identifying the last listed
item instead of the tank having a problem (such as negative waterplane area).

ENTER PM command CONTENTS was not supporing 12-character quoted contents
descriptions (requires updated PM.EXE).

ENTER PM command DISPLAY was trapping a run-time error when showing points
at unlimited lateral locations due to missing OUTBOARD and FIT statements.


Version 16.08A

MAXVCG /LINEAR now plots straight lines between points to be consistent with
the linear interpolation used in /LOOKUP mode.

SEAKeeping fully supports WAVE (SINusoid) as well as SPECTRA wave forms.

CONTENTS command (in both main program and Part Maker) consistently supports
unquoted double-word descriptions so long as the second word is not numeric.
This matches longstanding behavior for existing contents in the main program
and for the CONTENTS statement in Part Maker CREATE and MODIFY commands.
When numbers are needed in the description or to avoid ambiguity, using quotes
should always work (requires updated PM.EXE).


Version 16.08B

Help menu added a "SK manual" option to read the SeaKeeping User's Manual
(requires SKMANUAL.PDF).

CONTENTS was trapping "Unknown substance" for * density (since 16.08A only).

ENTER PM command SHELL was sometimes incorrectly affecting the shape at the
deck edge (since 15.84B only; requires updated PM.EXE).


Version 16.08C

TEMPLATE variable input field numeric verification no longer permits a suffix
other than "%", "s", "p", "a", or "f" after a valid number.

ENTER PM statement SHAPE now allows both component and shape specifications,
so the specified component shape is duplicated, assigned the specified shape
name, and becomes used by the component being created (requires updated PM.EXE).

ENTER PM command SHELL no longer moves points on the centerline transversely.

ENTER PM command SHELL 0 was sometimes removing deck edges (since 16.08B only).


Version 16.10

MAXVCG improved identification of failure cases due to flood points immersed
at equilibrium for floor VCG when FLD angles are present in LIMITS, reporting
the number of the lowest downflooding or weathertight point immersed at EQU.

ENTER PM command MEssage {varname} now displays the value of the named
variable (the same as PMX does; requires updated PM.EXE).

Upgrades of existing program directories by just copying updated files with
no security driver impact and no administrator account requirement are now
performed by default whenever possible by annual update release installers.

SETUPREG utility causes icons to appear with three distinct color schemes for
programs files, geometry files, and run/print files in operating system lists
while registering file associations for standard GHS extensions.  Note that
INSTALL, REINSTALL, etc. automatically run this utility during installation
(requires updated SECURITY package).


Version 16.10A

DAMSTAB /SDI421P parameter was added to work the same as the /SDI216P
method except that Required index R is calculated according to MSC.421(98),
also known as the SOLAS 2020 Amendment.  Note: The alternate Sfinal formula
for RO-RO ships is only available in the DAMSTAB2 wizard.

GROUND /FLOOR was incorrectly using 2% instead of 0.2% of the overall length
of the ship as the default maximum penetration when /MAXPEN is omitted.

ADD w /MAX:maxw no longer uses w as the maximum weight when its magnitude
exceeds maxw, instead always using the specified maxw (or trapping an error
if FIRM is included).

CONTENTS [(tanklist)] /COLOR:n now works to change the color used when the
current tank contents are displayed; an error is trapped if the selected tanks
do not all have the same contents.


Version 16.12

ADD /FREE[Lcg][Tcg][Vcg] subparameters apply when /MAX or /FIX is used to
allow changing only LCG, TCG, and/or VCG locations.  Note /FREE by itself
is the same as /FREELTV, and only /FREEV was supported in earlier versions.

SEAkeeping /SAMPles:n[,min,max] optional subparameters were added to sample
wave spectra over the specified minimum to maximum frequency range using a
constant bandwith method; also /SAMP:n performance was improved.

SEAkeeping /RELative parameter was added to specify that vertical motions
should be computed for the vessel CG and all critical points relative to the
wave elevation at the point of interest.  This puts an additional section in
the report and any data files.

SEAkeeping /DATA:FORCING reports forces and moments per unit wave amplitude.

SEAkeeping improved error handing for /HULL, /SAMP, and /CRT input.

SEAkeeping now only displays Froude number and its characteristic length when
non-zero /SPEED is specified.  Note Froude number is computed based on the
hull waterplane length if defined and non-zero, else on length overall.

SEAkeeping /HEADing:degrees is now valid within the range [-360,360] instead
of [-180,180] to be more consistent with typical seakeeping conventions.

WEIGHT /GYRadius parameter by itself assigns default gyradii to the
Light Ship based on the vessel geometry.  Defaults can also be assigned for
individual gyradii by mixing GF with specified values.  Inertia from any
longitudinal distribution can be used for individual gyradii where * is given.

ADD and WEIGHT parameter /GYRadius:li,ti,vi,tv,vl,lt was trapping an error
for negative product of inertia gyradii (since 16.06 only).

Load Editor in Ground Points mode was showing the wrong sign suffix for
GCR coordinates (since 14.18A).


Version 16.12A

LOA and WOA system variables were added to return the actual overall vessel
length and width.

SEAkeeping /SPEED:knots was using incorrect speed values (since 16.12 only).


Version 16.14

Load Editor entry of soundings and ullages now ignores any "-" after an
apostrophe instead of subtracting inches from feet and allows inches ending
with a quote mark without an apostrophe.

Load Editor /NOFLood parameter was added to disable flooding tanks by
right-clicking in the Load columns, pressing the F11 key, or entering FL.

PM command RENDER /WPL:heel,trim,depth was not respecting metric length units
(requires updated PM.EXE).


Version 16.14A

TEMPLATE /POS:ADJacent subparameter choice was added to align outside
the base window side indicated by the other /POS choices.  For example,
RIGHTTOPADJ is adjacent to the top of the right side, TOPRIGHTADJ to
the right of the top side, RIGHTADJ to the middle of the right side, and ADJ
by itself to the middle of the side with most space to the edge of the screen.

TEMPLATE /HIDE parameter was added to hide all previous program windows
while the dialog is active, but still use them for positioning.

SOLVE sometimes trapped a "stack overflow" run-time error (since 16.12A only).

EXTEND HOPPER now correctly handles geometries with shift vectors (requires
updated GHSX.EXE).


Version 16.14B

TEMPLATE image fields added optional /Width:c parameter to specify the number
of average-size characters for the image width.  Note that an image retains its
original proportions unless both /Height and /Width parameters are included
specifying different proportions.

MESSAGE HEADSTART now also replaces any consecutive dashes with spaces for
screen header output.


Version 16.16

Seakeeping Wizard was added to complement the SEAkeeping command, including
short-crested wave analysis and easy-to-use interface for seakeeping setup.

SEAkeeping /DATA:VA subparameter was added to output a CSV data file of
response variance data.

SEAkeeping corrected a sign error in its physical mass matrix, which was
yielding unusual roll and sway RAOs near resonance when the CG was far from
the seakeeping origin.

SEAkeeping was computing incorrect values for WAVE J1 general JONSWAP spectrum.

SEAkeeping added Root-Mean-Square response amplitude to Statistics Table.

WAVE (SPEctra) O6 freq1, hsig1, lambda1, freq2, hsig2, lambda2 defines
an Ochi-Hubble six-parameter two-component wave spectrum using modal frequency
in seconds, significant wave height in current weight units, and shape parameter
for spectral energy concentration around the modal frequency.

WAVE (SPEctra) O1 hsig defines an Ochi-Hubble one-parameter most-probable
significant wave height spectrum for seakeeping analysis.


Version 16.16A

MB module significantly improved ability to solve for mutual equilibrium
for latched interactions where heel stability of the primary vessel depends
on support from a secondary vessel (such as a stabilizing barge).

TEMPLATE /HIDE was hiding the program off the taskbar (since 16.14A only).


Version 16.18

MB module improved penetration of connected points at mutual equilibrium for
ground point interactions.

STATUS SUMMARY alignment and formating were improved for fancy boxed reports.

TEMPLATE /HIDE was sometimes not working properly with non-persistent dialogs
(since 16.14A).

SEAkeeping was omitting the 5th critical point in the Statistics Tables when
exactly five critical points were given.

SEAkeeping now computes responses at default 1 meter wave amplitude (instead
of 1 foot amplitude) when using metric units.


Version 16.18A

MESSAGE REPSTART was unnecessarily displaying "REPSTART" (since 16.12A only).


Version 16.18B

PERM REPORT now shows full 25-character tank descriptions instead of
truncating to 20 characters.

READ (DATA) file without the /Unicode parameter was not working properly for
files starting with a Unicode byte order mark (since 15.52 only).

ENTER PM was deducting port/starboard components from the wrong side
(since 16.18 only; requires updated PM.EXE).


Version 16.20

ENTER PMX statement ROTATE now fully supports rotations about any axis,
not just the longitudinal axis (requires updated PMX.EXE).

WAIT BREAK no longer hangs when used with SCREEN MIN or TEMPLATE /HIDE,
instead temporarily showing the command window then restoring its hidden
state once control is resumed by pressing the Esc key (since 16.00A only).


Version 16.20A

LIMIT FLOODHT > 0 is now supported, with 1 centimeter used as the effective
minimum limit value divisor when the RA and MAXVCG commands compute limit
margins to avoid division by zero and huge margins for tiny height differences.

RA limit reports now show FAIL instead of UNDEF for limit margin percentages
less than -99 that are not truly undefined,


Version 16.20B

SEAkeeping /SHW:l,t,v|CRT parameter was added to compute the probability
and frequency of "shipping water" deck immersion events either for the point
at specified longitudinal, transverse, and vertical coordinates or for all
seakeeping Critical Points if the CRT subparameter is given.  Probabilites
are computed using the relative motions at each location, and freeboards are
computed as the vertical heights of points above the waterplane.

SEAkeeping /TIME:hours parameter was added to define the time interval in hours
used for computations like /SHW and /CONF; the default is 24 hours.

SEAkeeping /CONFidence:percentage[,hours] final subparameter is now an optional
override for any interval specified by the /TIME parameter.


Version 16.20C

ENTER PM command READ file.FRA was not respecting "M" suffix for locations
in meters instead of default feet (requires updated PM.EXE).


Version 16.22

SEAkeeping /SLAM[:location|FRA [,velocity]] parameter was added to compute
the slamming probability, frequency, and pressure at a single longitudinal
location or at all frame locations if FRA is specified; the default is the
forward perpendicular, which is required.  The threshold velocity (in ft/sec
or m/sec depending on units) may be specified; if omitted, it is computed
according to the local geometry.  Significant pressure (i.e the average of
the highest tertile of expected pressures) will be returned for all locations,
excluding those within 0.01*LOA of the vessel ends.  Slamming pressure is
computed using a non-dimensional form coefficient k1 computed for each
slamming section using either the Macagno, Chuang "Wedge", or Ochi 3-Parameter
method, as automatically selected based on the geometry and marked on the
Slamming table using ^ for Chuang, + for Ochi, and no mark for Macagno.

WAVE (SPEctra) PM wspeed now traps an error if wind speed is too small to
yield meaningful results.

SEAkeeping was yielding exaggerated roll ROAs when VCG was far from the
seakeeping origin due to an inadvertent sign disagreement in a sway-roll
coupling term (since 16.16 only).

SEAkeeping was yielding reduced or increased pitch RAOs at certain headings
when surge was significant and VCG was far from the seakeeping origin due to
a sign disagreement in a surge-pitch coupling term.

Copyright (C) 2018 Creative Systems, Inc.