hilst settings concern only the currently selected instance.
For instance assume that you are in the Bermuda Shorts business and you want various ideas concerning a new ad campaign:
Or assume that the 4 horsemen want from you to quickly present some concept proposals related with a terminal event that they have in mind:
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Horticulture and Landscape in same time.
The most common plastic materials used as agricultural films are the low density polyethylene (LDPE, with a density less than 0.93 kg m−3), the copolymer of ethylene and vinyl-acetate (EVA)
Also here you can find the characteristics of the flexible materials for greenhouse covers (adapted from CPA, 1992 and Tesi, 2001) as much as i get.
UV-PE Film ( UV-PE~ polyethylene Long life or UV)
Thickness (mm) = 0.18
Direct PAR transmissivity (%) = 90
Diffuse PAR transmissivity (%)= 86
Long-wave IR transmissivity (%)= 65
EVA Film ( EVA~Ethylene vinyl-acetate copolymer)
Thickness (mm) = 0.18
Direct PAR transmissivity (%) = 90
Diffuse PAR transmissivity (%)= 76
Long-wave IR transmissivity (%)= 27
and here you will find the global heat transfer coefficient’ (K in W m−2 °C−1) for the above greenhouse covering materials, measured under normalized conditions (temperatures: exterior: −10°C, interior: +20°C, wind: 4 m s−1). (Source: Nisen and Deltour, 1986.)
Cover Clear sky Overcast Sky
Single PE 8.8-9.0 7.1- 7.2
Single EVA 7.8 6.6
Note : the PAR radiation (photosynthetically active or photoactive radiation and its the amounts to 45–50% of the global radiation; Berninger, 1989)
The name PAR is used to designate the radiation with wavelengths useful for plant photosynthesis. It is accepted that the PAR radiation ranges from 400 to 700 nm (McCree, 1972), although some authors consider the PAR from 350 to 850 nm.
The composition of the radiation changes with time, as a function of the Sun’s elevation and the cloudiness. When the Sun is low over the horizon, the short wavelengths are reduced (less UV and more red). The clouds reduce the amount of energy, greatly decreasing the NIR.
The PAR proportion in relation to the global radiation increases with scattering (diffusion). It is lower with clear sky and in the summer (45–48%).
kind regards
rafat …
ra' nella finestra di Grasshopper, in alto, insieme agli altri set di componenti come 'Params', 'Maths', ecc.
Si tratta di un esperimento per cercare di ampliare in qualche modo l'ambito di utilizzo di Grasshopper.
Come sappiamo Grasshopper e' nato per consentire l'utilizzo parametrico di Rhino. Le definizioni di Grasshopper permettono di registrare i passi necessari per costruire gli oggetti, nonche' di variare i dati utilizzati dalla definizione, ad esempio oggetti geometrici, lunghezze, angoli, ecc.
Quando modifichiamo i valori utilizzati dalla definizione Grasshopper automaticamente ricalcola il tutto e ci mostra la preview del risultato.
A questo punto, se il risultato e' soddisfacente, possiamo dire a Grasshopper di inserire gli oggetti in questione nel documento di Rhino, cosicche' li vedremo apparire nelle viste come veri e proprii oggetti Rhino.
Questo modo di lavorare ha avuto un grande successo tra gli utilizzatoti di Rhino, rendendo molto piu' agevole la costruzione di oggetti nel caso in cui sia necessario procedere per tentativi, verificando il risultato prima di stabilire la forma finale da ottenere.
Il successo di Grasshopper pero' ha anche mostrato quanto sia comodo poter definire graficamente le procedure di costruzione, e in generale poter utilizzare Rhino tramite i componenti, ad esempio gli slider, che tutti noi, suppongo, vorremmo avere a disposizione anche quando usiamo Rhino nel modo classico tramite pulsanti e comandi.
Quindi col passare del tempo sono apparsi sempre piu' Add-on per Grasshopper che permettono di eseguire operazioni particolari o anche di utilizzare Grasshopper in ambiti diversi dal concetto originale di 'History programmabile'. Accodandosi a questa tendenza, edoc prova a costruire dei componenti che permettano di operare direttamente sugli oggetti Rhino, cioe' curve, superfici, layer ecc. appartenenti al documento Rhino su cui stiamo lavorando. L'idea e' permettere di utilizzare la comoda interfaccia utente di Grasshopper anche per operazioni che solitamente sono eseguite in modo tradizionale con pulsanti e comandi, o anche tramite script.
Come gia' detto, e' un esperimento. I componenti nascono, muoioni e cambiano molto spesso, nel tentativo di capire cosa puo' essere utile e cosa puo' fuzionare o meno.
Segnalazioni di bug, suggerimenti, considerazioni ecc. sono benvenuti.
se qualche anima pia volesse tradurre questa presentazione gli faremo un monumento equestre!
grazie e scusate
gg
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nza dal centro delle facce ad un punto fisso per determinare quant'è il valore dell'offset per quella faccia.
Prova questa soluzione per ora:
- abilita il componente disattivato all'inizio;
- il componente curve offset non funziona bene, domani vedo se riesco a crearne uno migliore;
- inforna (bake) la brep risultante e convertila in mesh da rhino;
- per dargli spessore, fai l'offset solido della mesh in rhino per l'ultima fase, funziona meglio.
I've used the distance from the center of the faces to a fixed point to determine the value of the offset.
Try like this:
- enable the first component disabled;
- offset curve don't work perfectly, I'll try to fix it maybe...
- bake the brep and convert it into mesh in rhino;
- for the thickness, do a solid offset of the mesh in rhino for last phase, it just works better.…
n account of the position of the sun and weather cannot be expressed in terms of a single set of luminous intensity values (which is what IES files do).
With regards to your example files, I agree with Chris. The primary reason for the low illuminance levels is that the light bounces are getting lost in the tube. Have you checked with the manufacturer/distributor if the location of the IES file should be inside the tube and not flush with the ceiling? Physically modelling such tubes in lighting software like Radiance (which is what HB uses) or AGI32 is a fairly expensive proposition. This is one of the reasons why manufacturers provide photometric data for such devices (however simplistic that data might be).
The candelamultiplier increases or decreases the luminous intensity values. So it will have a direct impact on the calculation. The primary reason for having that input was to enable users to do some testing with different lamp types and environmental factors such as dirt depreciation. You need not change them for your simulation. Assuming that the IES file is inside the tube, in order to make this calculation work inside HB you'd have to crank up the calculation settings to a very high level (start with -ab 10 -ad 4096).
Finally, due to shortcomings in the annual simulation software (Daysim), IES files will not work directly work with annual calculations. However, there is a fairly easy workaround for that issue. In case you are planning to run annual calculations with IES files, please let us know here.
Sarith…
me research involving shades and and solar radiation and I need the sun's path through the entire year to fully optimize the design. This far I've been able to simulate what I want by having my shadders following a mock solar orbit around them, what I need to know is to use a model that simulates solar paths, use it as an attractor point and have my shadding surfaces follow it, pretty much like that I am doing right now (or so I think)
Here's where my questions come around:
I remember finding somewhere on the internet a definiton that simulates the sun's path through the year; I think I can find it again and use it for my purposes. I think that I could just run the GH definition, bake the geometry and then upload it to Ecotect and have it run so I can get the data and keep working over that, then feed the geometry again to Ecotect, ad nauseam. However I think that is a very slow process.
Is there a way that I can run an Ecotect plug in of sorts within GH, that way I can get my data IN grasshopper and model accordingly?
Does that make sense?
Thanks a lot for any input.…
Added by Antonio Tamez at 3:40am on October 24, 2011
s for the sunlight hours analysis.
I'm producing BRE Annual Probable Sunlight Hours calculations and so to match the BRE approach, I'm using 100 sun vectors, each representing 1% of probable sunlight hours. I could use the Sunpath and Analysis Period components to produce sun positions for the whole year, but this gives results that do not fully reflect the BRE methodology - which is important here. I'm detailing this just to clarify that this isn't a full annual calc of 8760 hours for 350 surfaces.
Anyway, when I run the calc, it takes about an hour to run, but the Sunlight Hours Component itself reports a calculation time of 3 seconds! Does this mean that the rest of the time is all about prepping the brep geometry? If so, is there a reason why this is much slower than when using a view of sky recipe and exporting to radiance. For the same project, I completed a view of sky calculations and based on the number of test points and -ad setting, this was completing about 5.25 billions rays so I understand why that took an hour.
Any thoughts as to why the sunlight hours calc seems to take so long?
thanks
Nick
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s topology gets pretty bad for use in CAD programs, since they are "in and out" at the same time. Generate naked edges and non-manifold edges. The problem itself is when I make an offset of the surfaces, which create "bad objets" in Rhino. I'm using Mantis, a plugin for Mathematica software, and one based on this the Math Surfaces script from http://www.co-de-it.com/wordpress/code/grasshopper-code. Both give me errors. I have tried to make a merge with the normal flip in the same model, but the error continues. If I do a split, in Rhino, there is no problem to create a solid offset, but the opposite is totally different if I make a Mirror. Can you help me with this complicated issue? Thank you.…
a pain to use sometimes. I recently found this great post:
http://www.grasshopper3d.com/forum/topics/formatting-numbers-in-grasshopper
which points to the msdn .net framework standard numeric format strings:
http://msdn.microsoft.com/en-us/library/dwhawy9k.aspx
and the custom ones too:
http://msdn.microsoft.com/en-us/library/0c899ak8.aspx
Sooo... today I was trying to make a 2D array generator for RGB values to use with a RGB LED and an Arduino. For instance, declaring a 2D array in Arduino:
int color[3][3]={{255,0,0},{0,255,0},{0,0,255}};
I'm using the blend color component to spit out transitions between two colors. I want the list in the panel to be in the format above, so I used both the expression component and the string format component (are they the same under the hood?). In any case, if I have R, G and B values coming into the component, I want to format them so the come out looking like {R,G,B}, so I can just copy the output in a panel and paste it into the Arduino IDE. But what about {curly braces}. If the expression/format component uses them in it's syntax, for instance:
Format ("{R:0},{G:0},{B:0}",R,G,B)
how do I get them into the formatting string? I tried escaping them like:
Format ("\{{R:0},{G:0},{B:0}\}",R,G,B)
but that just makes the component angry
Escaping characters is explained in the formatting references above. Is it implemented in this component? Should I be looking at a different approach?
I've included a sample file below.
Thanks!
~BB~
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