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How to find a "word/string" in a text file if I don't use Cells of Excel
...also need to change the format from Excel output. I have done the code for test, somewhat like this: Sub Macro2() 'Dim Data 'Dim Char As String * 1 Open "C:...\Desktop\VBA_read_input.txt" For Input As #1 r = 0 Do Until EOF(1) Line Input #1, Data If Mid(Data,9,6) = "#100001" Then...- alin09
- Post #5
- Forum: Microsoft VBA - Visual Basic for Applications
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How to find a "word/string" in a text file if I don't use Cells of Excel
I try to use VBA to read and write a text file without using "Cells". How can I find a "word" in a text file and change this word and output another text file? For example, I want to find all "structural" in the following text file and change it to "nonstructural". Suppose that size of the file...- alin09
- Thread
- Replies: 7
- Forum: Microsoft VBA - Visual Basic for Applications
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Impact forces of vertical landing
Everyone, thanks for the input! The vehicle is different than a conventional non-rigid airship. The vehicle is equipped with air landing cushions for vertical landing. Suction force can not be applied before the vehicle fully lands on ground. The cushion pressure can be controlled to avoid...- alin09
- Post #16
- Forum: Spacecraft engineering
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Impact forces of vertical landing
...(speed reduces from V to zero). My question is how accurate if I use acceleration and cushion deflection to calculate vehicle speed 1/2MV^2=Fd=M*a*d? I have asssumed that the acceleration is constant though it is not. The time used for landing might be just around one second. The vehicle...- alin09
- Post #6
- Forum: Spacecraft engineering
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Impact forces of vertical landing
...analysis of FE modle to acceleration or impact force that the vehicle can stand. Landing cushion is not in the FE model. Then, according to energy equation 1/2MV^2=Fd=M*a*d, I can calculate a speed with the acceleration and landing cushion deflection. Not sure if this simple way is correct or...- alin09
- Post #3
- Forum: Spacecraft engineering
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Impact forces of vertical landing
How to calculate the impact force when an lighter-than-air vehicle performs Vertical Landing? Actually, the vehicle lands vertically on the ground using air cushions. I tried to establish a speed corresponding to the impact forces. The impact forces are obtained from max ground reaction force...- alin09
- Thread
- Replies: 15
- Forum: Spacecraft engineering
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How to bond two surfaces of two solids together?
Blas, Thanks for the reply. It is not easy to create many RBE3 manually. To make same mesh at both surface of solids might not be applicable to two solids. I just found out that there is a contact option in PATRAN Load/BC. But the input file can only be solved by MD NASTRAN, not regular... -
How to bond two surfaces of two solids together?
Thank you, Onda. I don't have MD Nastran. I'll check about that. -
How to bond two surfaces of two solids together?
Onda, Greg, thanks for the reply. It sounds that the following methods can be used to bond two surfaces: 1.merge coincident nodes 2. CWELD connection 3. CFAST connection 4. RBE3 (someone suggest me this method) All these ways need manual creation of grid points at the surfaces. I was wondering... -
How to bond two surfaces of two solids together?
Does PATRAN/NASTRAN have the capability to bond two surfaces of two solids together? I tried to model an assembly consisting of two parts. The two parts share one surface. How can I glue these two together in order to obtain same nodes and mesh at the bonded surface? -
How to write the statement for MAX and MIN safety margin?
Blas, Thanks for the reply. I know the meaning of margin of safety and how to calculate. But I don't know how I can get the first 10 maximum and minimum values of margin of safety by using the statement MAXMIN (DEF) TTTT (BEAM,10) MAXALG(10) MINALG(10) in NASTRAN input file? What do I use to... -
How to write the statement for MAX and MIN safety margin?
How to write NASTRAN statement for output of safety margin: MAXMIN (DEF) TTTT (BEAM,10) MAXALG(10) MINALG(10)? I know the how to write the ourput for stress and forces but don't know which word in NASTRAN is used for safety margin (replacing TTTT in the above statement). I tried to find it in... -
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How to constrain some nodes immovable in one direction(only negative)?
Thanks a lot, everyone! I solved a simple beam problem, which has some part on the ground. From Utilities->Applications->Linear Gaps, I used Gap to Ground option. The result shows reasonable. The beam elements contacting the ground can deform above the ground but not into the ground. -
Analysis of a 3D Truss Structure
Blas, Thanks for the reply. IF I constrain all the rotational DOF of all truss nodes, the problem can be solved and there is no singularity. In reality, I don't need to form triangles of beams/rods to make the truss structure stable, some pretension cables can be used to make the truss... -
Analysis of a 3D Truss Structure
Johnhors, Onda, Thank you for the reply. I used CROD element to model the truss because the truss members can only hold tension and compression load due to the joint design. If I constrain 4,5,6 DOF of each grid point, there is no singularity. My question is that "Is this a correct way to... -
How to constrain some nodes immovable in one direction(only negative)?
Onda, Thank you for the helpful post. In order to test 3D modeling, I tried an example of a simple 3D cantilever beam. The picture is attached, and the beam is fixed at one end and forces are applied on the top surface. (My Patran has problem of generating jpg file and I can get bmp file, not... -
Analysis of a 3D Truss Structure
When I used Cbar and constrain the 4th 5th and 6th DOF of each grid point, the model will be solved. But my question is that the structure is a 3D truss, some grid points might be able to rotate with respect to the original coordinate system. Or I can make the assumption that the members can...
