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Modeling Languages





A modeling language is any artificial language that can be used to express information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure; modeling languages can be either graphical or textual. The Unified Modeling Language (UML) is a general-purpose, developmental, modeling language in the field of software engineering, that is intended to provide a standard way to visualize the design of a system.

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We are exporting from Tekla to IFC format.
Some of the resulting  plate dimmensions are incorrect.
The problem seems to be the flat plate definition in the IFC file.
For example a 10 x 75 mm flat plate is defined as
#867= IFCRECTANGLEPROFILEDEF(.AREA.,'FL10*75',#169,10.,110.);
The plate ends up being 10mm x 110mm rather than 10mm x 75mm.
We can't figure out where the incorrect flat plate dimmension is coming from.
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i wants to know the relationship between domain model and class diagram
I've been on the periphery of dimensional data modeling for a while, while knee deep for years in traditional ERP relational models and a de-normalized data warehouse, and lots of SQL data analysis. I'm in a non big data environment.

I've never understood the purpose of (nor the mechanics) dimensional data models. Now that I read a few blogs, I can better ask my questions. Here's a good article and some pic's that helps clarify my perspective on the structure of a dimensional data model.

dimensional data modelDimensional data
- Am I correct that this data modeling technique is ultimately done for performance purposes ?

- So isn't this accurate: to get to the dimensional data model, the OLTP data is broken up, then ETL'd to the dimensional model, then to write reports, well, you bring it back together again ? As an outsider to dimensional data modeling, I've always said to myself, "why not just write the query against the OLTP ?" Because when I look at the dimensional data model I can't see how it's much different than a relational model. Using the example above, the fact table would be a relational table by simply storing the date of the transaction as opposed to a "date FK". Using this example, I just don't get it.

- Isn't this dimensional data model like fully normalized ? So to present this to the users, you have to write a traditional query ?
Below is an extract taking from a paper available at:

I need to understand it please very well. It is all clear until he starts the second paragraph.
The second paragraph mentioned an indicator I am not sure I understand the whole second paragraph.  Please help to clarify I am starting to study these models and their integration with GIS. Thanks

A model is a computer program that takes a digital representation of one or more aspects of the real world and transforms them to create a new representation. Models can be static, if the input and the output both correspond to the same point in time, or dynamic, if the output represents a later point in time than the input.

The common element in all of these models is the operation of the GIS in multiple stages, whether they be used to create complex indicators from input layers or to represent time steps in the operation of a dynamic process. Static models often take the form of indicators, combining various inputs to create a useful output. For example, the Universal Soil Loss Equation (USLE) combines layers of mapped information about slope, soil quality, agricultural practices, and other properties to estimate the amount of soil that will be lost to erosion from a unit area in a unit time (Wischmeier and Smith 1978). The DRASTIC model (fig. 1) estimates geographic variation in the vulnerability of groundwater to pollution, again based on a number of mapped properties
Hi Experts

Could you explain what exactly  means and what is the general purpose of the "Logical Only"  option in Er-Win table and column definition?

Accordingly to:

Thanks in advance
hi all,

other than Visio, any other DB  UML diagram tools you guy use to draw data modeling diagram without impacting the underlying database structure ?
who can suggest open source freeware for uml tools like (dia,, thanks

A while back, I installed an addon for World of Warcraft (WoW) which causes an audio alert to occur each time my character casts a Critical Strike. The addon is called CritSound and I downloaded it from here.

The addon works as expected but I don't like the default sound(s) -- which are human voice announcements. Instead  I'd like it to produce simple audio signals such as a bong or ding, etc. The addon does not come with alternate sound options but the author mentions how to add them in the description on the download page which I'm including here:

plays a sound when you perform a critical hit or healing.
includes your physical damage ,spell damage, ranged damage, healing and your damage shield.
CritSound includes three mode:
1.single mode: always plays the first sound in the list.
2.sequence mode: plays the sounds in the list one by one when you perform a critical hit continually.
3.random mode: plays the sounds in the list randomly.
Use /cs or /critsound to open the controlpanel.
if you use the sequence mode, you can modify the aging time for collecting your critical hits.
you can edit CritSound.lua to delete or add sounds.
for example, in the line 5 to 11:
spell = {
            "CriticalDamage.ogg",    --first time
            "Dominating.ogg",        --second time
            "Unstoppable.ogg",        --etc.
What does line with closed triangle BLACK (filled) arrowhead means? Usually arrowhead is either "open" or "closed" but empty not filled in, what is the difference?

Class Diagram
I am using a mix of Archimate and Visio, neither of which are satisfactory. I want to be find an app that is a cross between these and AutoCAD (for layers) and PowerPoint (for animation/visualisation). A use case might be - there are 9 integrations between System A and System B which at a high level is shown as one line, click on the line and it breaks out into the 9 showing direction of data exchange with  details about what those integrations are etc. So rather like an AutoCAD drawing for a building I could see different layers and level of detail etc. TIA.
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Dear all database experts here:

I am a beginner of database design. I want to have a tool to draw ER - Diagram and make script to create Mysql or Oracle database. Which tool is good for it?

1. Navicat

2. Enterprise Architect:

3. DBDesigner 4

Also, I am asking if I draw the ER diagram and normalize them, how could I verify my design is a good design?
Im looking to improve my mostly non-existent documentation when writing PHP. Ive purchased some books to refresh my knowledge on UML (which I havnt used since my college days and STD (State Transition Diagrams) seem to have been retired, as there is no mention of them anymore).

Does anyone have any decent documentation tutorials/books etc they could point me in to get going?

I know I could do a quick google search, and some smart alac Im sure will suggest it, but Im after recommendations of good books/tutorials.

Thanks in advance

I am new to GIS but I am surprised when I find the following statement in a paper. Is thie following statements still valid or this is old. Please let me know. Thanks

While GISs provide some extensive tools for analysis of spatial data, their capabilities for spatio-temporal modelling, and hence the handling of temporal data, have been considered limited. GISs were formerly known to handle time or dynamic variations in a process poorly.  Adhering to this view,  GISs, with their standard functionality, do not explicitly allow dynamic processes to be captured and analyzed. GISs have been traditionally associated with maps, and the capabilities of a contemporary GISs represent map-related ideas of layers, projections and generalizations.

I am trying to create a table that looks as follows:

    portfolio            return            risk
    SP                        6                    20
    NASDAQ            10                  25
The numbers are stored in variables and I am not hardcoding them and rest are headings.
How do I code for this.

Hi All,

I have built a function that is too slow. I was wondering if anyone knew a way to speed up/ vectorize a for loop function by a factor of 5 or 10? Her name is "MakeVolumeBinIdx"

The purpose of my program is to bin my input data according to a fixed Volume size. So each row should have (almost) the same size volume .

My Input data is made of Date,Time, Price,Volume which is tick data (transaction per transaction) of a stock.
My output: Date,Time, Open,High,Low,Close,Volume (the volume should be almost equal for each candles or bins)

I have included the function's code, the program, the data set and the R files as well.
Also, I have a Hp laptop that runs on intel i7 and windows8.

Thank you in advance :)

The function I need major help with
  ### PURPOSE: Find the indexes for a given size of volume bin, that is 
  ###            Find the indexes of the data.frame where the sum of the volume is equal
  ###             to the input volBinSize.
  ### INPUT: a vector of trades volume and the desired volume bin size
  ### OUTPUT: a vector indicating where each row belongs to which volume bin
  #create index
  volBinIdx <- numeric(length(Volume))
  #create cutting for each volume bin
  for(i in seq_len(length(Volume))){
    sumVol<-sumVol + Volume[i]  
    if (sumVol<= volBinSize) {
      volBinIdx[i] <- volBin
    } else {
      volBinIdx[i] <-  

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I have such event

Private Sub Fld_AfterUpdate()
    MsgBox Right(Me.Fld, 5)
End Sub

to the List box, within Access 2010 project. Upon that, I've selected one other option to that. I see nothing has been displayed. why?
I was wonder if someone could give me a  simple example of how to use BindableBase within a MVVM WPF project...

I need to implement an event when the DataContext is changed as I need to notify other classes that when they were initialized they they are null ?
In AutoCad we are trying to use AutoLISP and with other languages like C to run a small program with endlines.  It works fine until we go to do a Return. We get an error message saying unknown command. We are probably missing something simple but how could a return statement be added to this program without the error so we can just Return out of it? The code is posted below.

Any assistance offered would be greatly appreciated.

(defun C:pipebends ( )

(setvar "cmdecho" 0)
(setvar "osmode" 0)

(setq PT2 (getpoint "\n Select Location for Bends: "))


   (setq pt5 nil)
   (setq PT3 (car (nentselp PT2)))
   (setq PT (list PT3 PT2))
   (setq XP (entget (car PT)))
   (setq YP (osnap (cadr PT) "nea"))
   (setq YREM (cdr (assoc 0 XP)))
     ((equal "LINE" YREM)
     (setq ST (cdr (assoc 10 XP)))
     (setq END (cdr (assoc 11 XP)))
     ((or (equal "ARC" YREM) (equal "CIRCLE" YREM))
     (setq DIST (distance (cdr (assoc 10 XP)) YP))
     (setq ANGA (angle (cdr (assoc 10 XP)) YP))
     (setq ST  (cdr (assoc 10 XP)))
     (setq END (polar ST (+ ANGA (cvunit 90 "degree" "radian")) DIST))
     ((or (equal "POLYLINE" YREM) (equal "LWPOLYLINE" YREM))
     (setq CEN (OSNAP (CADR PT) "CEN"))
       (if (/= cen nil)
         (setq DIST2 (distance YP CEN))
         (setq ANGA2 (angle CEN YP))
         (setq END2 (polar YP (+ ANGA2 (cvunit 90 "degree" "radian")) DIST2))
         (setq ST YP)
         (setq END END2)

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I am using C# and MS Access or MS SQL in my applications, and work with VS Studio 2013.

I worked before with Sybase PowerDesinger.

Now, I started my own business, and I need to find the best tool that can help me in this matter.

I found Enterprise Architect and some other tools.

Any suggestion about the best one for me.
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If I have already modeled, rendered, and animated a fish, and I had video footage of a person walking in the park, and I'd like to make a new video with the fish appearing alongside that person, can anyone give me a head start or a general idea on how I can go about accomplishing that?

We see CGI being used in movies all the time, and I know those 3D models started from software like Maya. But I haven't the foggiest idea at this point on how to incorporate my byproducts in an actual video. Any help would be appreciated.

I'm a bit disappointed that this website doesn't have an Autodesk Maya category, but I hope someone will answer my basic 3D Modeling question.

I'm using Autodesk Maya 2013. Let's say I want to make a mug. So I start of with a Polygon Pipe object and have already shaped it to be the cylindrical body of the mug. The problem is, the Polygon Pipe has a hollow bottom (a big hole). As anyone knows, a mug wouldn't be useful if it's bottom is a big hole.

My question is, how can I close out the bottom for this mug without having to add another polygonal object and aligning it at the bottom to close the hole?
Let's say you have module A, B, and C

Module C depends on module B and module B depends on module A.

When describing module B, I state that it's dependancy is module A. How do I describe module B's relationship to C? (the opposite of a dependancy)

Thank you for your help!

I would like to use a UML tool inside of Visual Studio 2013 Pro. I know one is already available with the Ultimate edition but there is no way I can afford the $13,000 price Microsoft wants for Visual Studio Ultimate.

I am particularly looking for something that will use C# in the generation of UML. I know there is a free one at but that one works with Java.  I would like one like that that works with C#.

Thanks in advance
I am creating an ERD. I have 8 entities so far but I know I've got a long way to go. I think I want to split up orders and purchase orders but not sure in what way. Should I make 3 or 4 entities total out of the orders  and purchaseorders entities?

What else can I do to make this more realistic and correct?
hey guys, this is semi linked to my other question on business requirement software

do yall do UML diagrams? i do know a notable iOS lone developer with a very successful app who does not use UML diagrams cause he's just building by himself.

1) to all developers in software companies, do yall always use UML? or some form of documenting your system

2) to all lone developers, do yall use UML or yall don't?

i am getting quite stung by this whole documentation thing now - more from the angle that i need to have a lattice structure to hang my ideas so i can see how everything comes together.

Modeling Languages





A modeling language is any artificial language that can be used to express information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure; modeling languages can be either graphical or textual. The Unified Modeling Language (UML) is a general-purpose, developmental, modeling language in the field of software engineering, that is intended to provide a standard way to visualize the design of a system.

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Modeling Languages