Appendix

MedModel evaluates various fields and logic at different times during a simulation run. Some evaluate only once when the model prepares to run a simulation, called the translation time. MedModel evaluates others as necessary throughout the simulation. Below is a list of all expressions and statements by category, and a table telling which fields evaluate at translation and which fields MedModel evaluates continuously during a simulation. The table also tells where you may use an expression or statement.

Expression and Statement Groups

1. General Expression

Numbers, Variables, Math Functions, Functions Table, Distribution Functions, XSUB(), and Name Functions (i.e., RES(), ENT(), LOC()).

2. Arrays

Arrays of any dimension.

3. Location Attributes

Referencing a location attribute in any expression or assigning to a location attribute.

4. Entity-Specific System Functions and Attributes

Entity(), GroupQty(), ResQty().

5. General System Functions

Cap(), CalDay(), CalDom(), CalHour(), CalMin(),CalMonth(), CalYear(), Clock(), Contents(), DownQty(), Entries(), FreeCap(), FreeUnits(), OwnedResource(), TimesUsed(), Units(), and Variable().

6. Location-Specific System Function

Location().

7. Resource-Specific System Function

Resource().

8. Node Logic-Specific System Functions

Last(), Next(). (The Last function is valid only in Node Entry Logic and the Next function is valid only in Node Exit Logic.)

9. Downtime-Specific System Function

DTDelay().

10. Shift-Specific System Functions

ForLocation(), ForResource().

11. Preemption Logic-Specific System Functions

Preemptor(), TimeLeft().

12. Off-Shift & Break Logic-Specific System Functions & Statements

DTLeft(), Priority, and Skip.

13. Cost Functions & Statements

GetCost(), GetResRate(), IncEntCost, IncLocCost, and IncResCost.

14. General Statements: (Run-Time Only)

Activate, Animate, Assignment, Begin End, Break, BreakBLK, Close, Comment(#,
//, /*...*/), Debug, Dec, Display, Do...Until, Do...While, Goto, If...Then/If...Then...Else, Inc, Int, Local Variable, Log, MapArr, Order, Pause, Prompt, Read, Real, Reset, Reset Stats, Return, Report, Send, SetRate, Stop, String Expressions, Sound, Trace, View, WarmUp, While...Do, and Write/Writeline/XWrite. (You may not use the Log statement in Initialization or Termination Logic.)

15. Operation Statements (Group 1)

Accum, Combine, Create, Group, Join, Load, Match, Move, Rename, Route, Split As, Ungroup, and Unload.

16. Operation Statements (Group 2)

Free, Get, Jointly Get, and Use.

17. Operation Statements (Group 3)

Wait.

18. Move Logic-Specific Statements

Move For, Move On, and Move With.

19. External Spreadsheet File

Entity Location Expression File.

20. Graphic Statement

Graphic.

21. Wait Until Statement

Wait until.

Macros and Subroutines

A macro may be used in any expression field, but the macro may only contain expressions which return a value (e.g., Entries(LOC1), U(5,1)). When a macro is used in a logic field, the macro may include any logic element that is valid in that logic field. A subroutine may also be used in an expression field provided that the Return statement is used to return a value to the expression field. When a subroutine is used in a logic field, the subroutine may include any logic element that is valid in that logic field.

Valid Expression and Statement Groups by Field

When running a simulation, expressions and statements are either evaluated 1) once at translation (before initialization logic and before any events are created) or 2) continuously during the simulation run. The following chart categorizes the edit fields in this manner and shows the expression and statement groups that can be used in each field. Fields are classified as either expression fields or logic fields. Fields not listed on this chart are either menu fields or expression fields that accept only numbers.

Fields Evaluated Only at Translation

Field Name (evaluated at translation)	Field Type	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21
Variables
Initial Value	Exp	•	•
Function Table
Dependent Value	Exp	•	•
Independent Value	Exp	•	•
Simulation Options
Warm-up Hours	Exp	•	•
Run Hours	Exp	•	•
Replications	Exp	•	•
Interval Length	Exp	•	•
Path Networks
Node Capacity	Exp	•	•
Segment Distance	Exp	•	•
Speed Factor	Exp	•	•
Resources
Resource Units	Exp	•	•
Locations
Location Capacity	Exp	•	•
Conveyor
Length	Exp	•	•
Speed	Exp	•	•
Queue
Queue Length	Exp	•	•
Shifts
Shift Start Time	Exp	•	•
Entities
Entity Length	Exp	•	•
Entity Width	Exp	•	•

Fields Evaluated During Simulation

Field Names (during simulation)	Field Type	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21
Logic
Initialization Logic	Logic	•	•			•									•
Termination Logic	Logic	•	•			•									•
Entities
Speed	Exp	•	•	•	•	•	•													•
Path Networks
Traveling Time per Path Segment	Exp	•	•		•	•
Resources
Acceleration	Exp	•	•		•	•
Deceleration	Exp	•	•		•	•
Empty Load Speed	Exp	•	•			•
Full Load Speed	Exp	•	•		•	•
Pickup Time	Exp	•	•	•	•	•	•													•
Deposit Time	Exp	•	•	•	•	•	•													•
Node Entry Logic	Logic	•	•			•		•	•						•						•	•
Node Exit Logic	Logic	•	•			•		•	•						•						•	•
Location Clock DT
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Priority	Exp	•	•			•
Clock DT Logic	Logic	•	•	•		•	•			•					•		•	•
Location Entry DT
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Entry DT Logic	Logic	•	•	•		•	•			•					•		•	•
Location Usage DT
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Priority	Exp	•	•			•
Usage DT Logic	Logic	•	•	•		•	•			•					•		•	•
Location Setup DT
Setup DT Logic	Logic	•	•	•	•	•	•			•					•		•	•		•
Resource Clock DT
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Priority	Exp	•	•			•
Clock DT Logic	Logic	•	•			•		•		•					•		•	•			•
Resource Usage DT
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Priority	Exp	•	•			•
Usage DT Logic	Logic	•	•			•		•		•					•		•	•			•
Operation
Operation Logic	Logic	•	•	•	•	•	•							•	•	•	•	•		•	•	•
Preemption
Preemption Logic	Logic	•	•	•	•	•	•					•			•	•	•	•		•	•	•
Routing
Priority for Destination	Exp	•	•	•	•	•	•													•
Destination	Exp	•	•	•	•	•	•													•
Entity Output Quantity	Exp	•	•	•	•	•	•													•
User Condition Rule	Exp	•	•	•	•	•	•													•
Move Logic	Logic	•	•	•	•	•	•							•	•		•	•	•	•	•	•
Arrivals
First Occurrence	Exp	•	•			•
Frequency	Exp	•	•			•
Occurrences	Exp	•	•			•
Qty of Each Arrival	Exp	•	•			•
Arrival Logic	Logic	•	•	•	•	•	•								•					•	•
Shift Assignments
Priorities	Exp	•	•
Pre-Off Shift Logic	Logic	•	•			•		•			•				•			•				•
Off Shift Logic	Logic	•	•			•		•			•		•		•		•	•				•
Pre-Break Logic	Logic	•	•			•		•			•				•			•				•
Break Logic	Logic	•	•			•		•			•		•		•		•	•				•
Subroutines
Interactive Subroutines	Logic	•	•			•									•			•				•
Debugger
Debug Condition	Exp	•	•	•	•	•	•

Program Defaults

This section discusses and lists the default settings when you first run MedModel.

As in most software packages, MedModel makes certain assumptions regarding the most useful settings for the program. While your models may require different settings, an effort has been made to select the most common and helpful default settings.

Since MedModel can be used for a wide variety of applications, you may require different settings. As your models differ, so will the need to change these settings from their default. However, when MedModel is first launched and no INI file exists for it, the defaults in the following table apply. Some defaults involve edit field values, some are check box settings, etc.

Many defaults can be changed by selecting one of the Model Default options under the Tools menu. Other defaults can only be changed in the Build modules. Still others can only be changed by directly editing the .INI file.

After MedModel is first launched, the medmod.ini(initialization) file is created. To change the .INI file defaults, you must edit the it using an ASCII text editor (e.g., Windows Notepad). DO NOT attempt to edit the .INI file unless you are fully comfortable doing so and only after you make a backup copy of the original .INI file.

Default Values

Build Menu
Graphic library	promod.glb
Locations
Conveyor/queue style	roller
Conveyor/queue width (feet)	3
Conveyor speed (fpm)	60
Conveyor accumulating	accum
Conveyor entity orientation	lengthwise
Location statistics	time series
Entities
Entity speed	150 fpm (50 mpm)
Entity statistics	time series
Path Networks
Time/speed	Speed
Path color	blue/yellow
Resources
Speed	150 fpm (50 mpm)
Entity search	Longest Waiting
Resource search	Closest resource
Resource statistics	By unit
Processing
Snap to border	off
Variable statistics	time series

Tools Menu
Long build menu	on
Confirm record delete	on
Recalculate path lengths when adjusted	on

View Menu
Snap to grid	off
Show grid	off
Grid size (VGA full layout)	90 grid units
Scale - distance	1 ft/grid unit
Scale - time	.01 min/grid unit
Background color	lt. gray
Edit table font	Arial 8 Regular
Edit table color	Gray

Directories
Models	c:\ProModel\models
Glib	c:\ProModel\glib
Output	c:\ProModel\output

INI Defaults
Graphic Editor
Text alignment	center
Text frame type	transparent
Text frame shape	rectangle
Text font	Arial 8 Bold
Text color	black
Text frame border color	black
Text frame fill color	white
Variables
Digit font	Arial 8 Bold
Digit color	yellow
Digit frame type	recessed
Digit frame shape	rectangle
Digit frame border color	black
Digit frame fill color	royal blue
Conveyors/Queues
Queue border color	black
Queue fill color	dark gray
Gauges/Tanks
Gauge/tank fill color	maroon
Gauge/tank border color	black
Gauge/tank empty color	white
Gauge/tank - no border	checked
Gauge/tank - show scale	checked
Other
Autosave (in minutes)	10
Print layout - print options dialog - bkgrnd color	unchecked

ActiveX Objects

MedModel’s ActiveX Automation capability allows you to externally create, view, and edit model elements such as locations, entities, and variables. Using Visual Basic (or any other ActiveX-enabled language), you can add capabilities to MedModel including:

Customized user interface with table inputs
Custom-designed parameter screens
Automatic model creation from external data sources (e.g., Excel spreadsheets, databases, or ASCII text files)
Software execution from another application

You can also use MedModel’s ActiveX capability to access any of the following actions and tables (any table not mentioned in the following list is not currently ActiveX enabled).

More information on ActiveX Automation can be found in the ActiveX User Guide, which is located in the documentation folder within the MedModel directory.

Glossary

Cost Statistics

Statistics collected on a cost basis (e.g., total cost and average, non-use cost). You have control of how MedModel collects these statistics. You may collect information through statements, base them on the system clock, or use a combination of both.

Counter

A counter is a location or variable graphic used to display the contents of a location or the current value of a variable during animation. A counter consists of a frame, a specification of the digit color, and the font. If the number being displayed requires more digits than the maximum specified, the counter simply expands to the left. MedModel displays real values showing only 2 decimal places. For example, a variable equal to 4.8936 would display 4.89 on the screen.

Dialog Box

A dialog box is a pop-up window used to enter information or select options. Movement from field to field in a dialog box is accomplished by clicking in the field with the left mouse button or by using the Tab key. To accept input made to a dialog box press Enter or click on the OK button. To cancel any changes made to the dialog press Esc or click on the Cancel button. For help on the dialog, press F1 or click on the Help button. If no Help button is shown, you may select Help from the main menu.

Edit Tables

An edit table is a powerful editing window used to add, delete and edit modeling and language elements such as entities or locations. It is similar to a spread sheet editor in that it provides maximum visibility of element lists while still allowing each field of a particular element to be directly edited.

File Name

A file name is any name used to identify a file. File names may include a path (e.g., C:\REPORTS\DATA) as well as a terminating period with up to three additional characters as an extension (e.g., DATA.TXT). File names are case insensitive.

Font

A font is a collection of characters sharing the same attributes such as height, width, and typeface. A font determines the appearance of text. Select fonts using the font dialog which shows how the font will appear.

Frame

A frame is a graphical border or background for placing text or displaying values. Frames have a type (raised, recessed, transparent), shape, color and size. Frames are optional and you may use them only to enhance the appearance of the graphic layout. If you do not desire a frame, select Transparent as the type.

Gauge

A gauge is a graphic bar that extends and retracts to represent the current contents of a location. You define a gauge by the fill color, the empty color, and the gauge border color. You also specify the fill direction (up, down, left or right).

Integer Number

An integer number is a whole number ranging from -2,147,483,648 to 2,147,483,647. Integer values may not include commas, so enter the number 5,380 as 5380.

Library Graphic

A library graphic is a graphic defined and edited using the Library Graphics Editor. Use library graphics to represent locations, resources or entities, or as part of the layout background with no association to any model entity.

When used to represent a processing location, library graphics may have entity spots defined for them so entities that enter the location will appear graphically on the entity spot.

You may reference a Library graphic multiple times and each reference may have a unique size, horizontal or vertical inversion, rotation, and color.

Main Entity

The original or input entity used in routing logic. You may create new entities from the main entity using the CREATE statement or through multiple routing blocks.

Main Menus

The main menus are listed along the main menu bar at the top of the application window and provide access to all of the dialogs and commands necessary to build, run, and analyze simulation models.

Name Index

During simulation run time, MedModel converts the name of each location, entity, and resource to a list index number for efficient access and flexibility in assigning names to variables, attributes, etc. The index number corresponds to the order in which the elements appear in the edit table list. If five locations were defined, they will be identified by the index numbers 1 through 5 at run time. A name index may be assigned to a variable or attribute by referencing the name itself (e.g., Attr1 = EntityA). You may also test for a name index by referencing the name (e.g., if Var5 = Loc3).

Note

A note is any comment or other information typed by the user that is for information only and disregarded by MedModel.

Numeric Type

A numeric type specifies whether a numeric expression is of type real or integer. If, for example, a variable is of type “real,” then the variable can only represent some real number.

Numeric Value

A numeric value is any real or integer number such as 3.68 or 52.

Parameter

Parameters are variables used in a subroutine which are local to or have scope only within the subroutine. Arguments or numeric expressions passed to a subroutine are assigned to the parameters for use inside the subroutine.

Park Search

A park search defines the sequence where a resource looks for nodes at which to park after completing a task assuming no other tasks are waiting.

Paths

Paths define the course of travel for entities and resources between locations. You may define a path for a specific entity and routing, or a network of paths shared by several resources and entities. Define movement along a path in units of time, or speed and distance.

Path networks consist of nodes connected by path segments. Any node may have multiple input and output segments.

Positioning Spot

An entity spot is simply a graphic position relative to a location or resource and displays any entities occupying the location or resource.

For any given location you may place one or more entity spots on the graphics layout. Entities to enter a location appear on the first available entity spot in the order they are placed. If an entity enters a location and all the entity spots are filled, the entity will appear on the last entity spot.

For resources, place the entity spot where it appears when a resource carries the entity.

Preemption

Preemption is the act of bumping or replacing an activity currently using a location with an activity of a higher preemptive priority. MedModel handles preempted activities differently depending on the location preempted.

For locations, MedModel puts the preempted activity (any current entity or downtime) in a preemption list for that particular location until it can resume its activity at that specific location unit.

Real Number

A real number is a number ranging from 1.7 X 10 -308 to 1.7 X 10 +308. Real values may not include commas, so enter the number 5,380.5 as 5380.5.

Examples: -2.87563, 844.2, 65.0

Reference

A reference is a name entry in an edit field that references a defined model element. If you change the name of the model element, all references to the element automatically change to reflect the change in name.

Region

A region is a rectangular area on the graphic layout that represents a location. Defining a region is useful when you import a layout from a CAD drawing and you want to designate a portion of the layout to represent a particular processing location. A region should have one or more entity spots associated with it in order to be meaningful.

Resource

A resource is a person or item used to perform an operation or activity. Common resources include human operators, inspectors, forklifts, and other vehicles. Use resources used to perform operations on entities at a location, transport entities between locations, or perform activities on a location during a downtime.

Resource Point

A resource point is a screen position where a resource will appear when it arrives to park or perform a task at a particular node. When a resource arrives at a node, it will appear on that node unless you define a resource point for that resource at that node. Resource points provide a way to have several resources positioned at the same node without all appearing on top of each other.

Routing Priority

A routing priority is the priority given to a routing for accessing a destination when capacity becomes available. MedModel defines the routing priority as part of the Destination field in the Routing Edit Table. A routing priority applies where two or more entities wait at a location for a routing destination to become available. The routing priority breaks a tie when deciding which entity has access to the destination location first when it becomes available. (See Selecting Incoming Entities in the Location Rules Dialog.)

Scroll Arrow

You can use the scroll arrows on either end of a scroll bar to move the contents of a window or list box. Clicking once on a scroll arrow moves the contents one line. Holding down a scroll arrow scrolls continuously.

Scroll Bar

A scroll bar is a Windows control for scrolling the contents of a window. Scroll bars operate in three different ways:

Click on the scroll arrows at either end of the scroll bar for incremental scrolling.
Click on either side of the scroll box for scrolling one window at a time.
Drag the scroll box with the mouse to scroll to a specific position.

Scroll Box

A scroll box is a small box in a scroll bar that shows the position of what is currently in the window or list box relative to the contents of the entire window.

Shell

The temporary entity (representing grouped entities) to which MedModel assigns all costs and statistics until you ungroup the entities. Once ungrouped, MedModel divides all costs among the entities.

Status Lights

A status light is a circle that lights up with different colors depending on the status of the location. You can place a status light anywhere relative to a location for showing the status or current state of the location. At run time, you can display a window showing what status each color represents.

String

A string is a series of characters enclosed in double quotes (e.g., “Station A”). You may use strings to write text to a file or to display a message on the screen.

System Menu

The system menu appears as a dash mark at the upper left corner of most windows. The main function of the system menu is to close the window. To do this, by either double-click on the menu button or click on the button once and select Close from the menu options that appear. ALT + <space bar> also pulls up the system menu.

Text

Text refers to words that you wish to display on the graphic layout. Each specification of text has an associated font, color, frame, and orientation (up, down, left or right). You can rotate only true-type fonts.

Time Statistics

Statistics collected on a time basis (e.g., time in system, average minutes per entry, and average contents). You cannot control how MedModel collects these statistics since MedModel bases them solely on the system clock.

Work Search

A work search defines the sequence in which a resource looks for work at locations where work may wait to be performed.

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