Recent Posts

31

Announcements / Trial Versions of NoiseMap

« Last post by roger on June 09, 2017, 02:28:50 PM »

We offer a free trial version of NoiseMap five.  This is a fully-featured, fully working version of NoiseMap. The only limitation is that it will stop working after a trial period, which we can set according to your reasonable requirements.  The trial version may only be used for evaluation. It may not be used for any commercial purposes.

The Trial Version requires a plug-in USB dongle which must be sent to you by mail/courier.  If you live outside of the UK, we will send this by international courier and we will charge you the courier fee, currently GBP60, payable in advance. 

We require your full postal address and contact details so that the courier can deliver the package to you.

We are sorry that we need to make this charge, but this is necessary to discourage speculative requests.

32

Support / Where do I download updates to NoiseMap?

« Last post by roger on June 09, 2017, 02:17:44 PM »

If you already have a NoiseMap five licence, then open NoiseMap and go to Help>Check for Licence/Software Updates and you will be taken to your licence checker. This will show you whether your licence is current and will offer you any applicable downloads, including updates that you are entitled to receive.

If you don't have a NoiseMap five licence (either because this is a new installation or you only use NoiseMap Enterprise, then email support@noisemap.com with your details (inlcuding dongle number) and we will assist.

33

Announcements / NoiseMap 5.2.1 Released

« Last post by roger on June 09, 2017, 02:00:06 PM »

NoiseMap 5.2.1 was released on 5th May 2017
It adds even more functionality to version 5.2 which was release in January 2017 (see below)

• Added option to building facade receiver generation function to limit generation to only buildings that contain an address point
• Added "Match prefix" and "Match suffix" options to Find window (and select script function) to only match text the start and/or end of an identifier
• Changed sound power level header column "SPL" to "PWL" in site noise source contribution breakdown csv output file
  

Release 5.2, 17/01/2017
• New results processor allowing the creation, display and export of receiver results and noise contours based on combining multiple stored and imported results with arbitrary arithmetic expressions
• Added loading of multiple contour and receiver result sets from different scenarios at the same time for direct display and use in expressions
• Added the ability to loading receiver results from an external csv file for direct display and use in expressions
• Added the ability to generate a script file to automate the loading of multiple results and contours and the creation of expressions
• Added additional format options for train service csv export including track-only format with one row per service/track pair (script and GUI support)
• Added new noise source contribution output csv file generation (optional) to all on-the-fly receiver calculations
• Added hotkeys for server/database, measure tool, display options, View-As-Colour, receiver and contour result load and display parameters, Cross-Section and 3D Viewer
• Negative track correction is now permitted in track property editor
• Fixed missing barrier properties and added absorbency column to exported barrier shapefile
• Fixed erratic behaviour of outline (not visible, not selectable) when added as the first object to a new database
• Fixed crash when editing identifiers for multiple selected outlines
• Corrected outline position co-ordinates listed in View->Display Model Parameters list
• Updated barrier shapefile mapping profile to include absorbency. Note: width is +ve for width, -ve for overhang
• Changed check for duplicate outlines to only check building outlines to allow overlapping address points etc.

34

Hints and Tips / I have been given 24-hour traffic flows. How do I apply them?

« Last post by roger on June 09, 2017, 12:45:10 PM »

You have been given the total traffic flow for each 24-hour period, in your case the 24-hour AADT (annual average daily traffic flow).  You haven't been given the traffic flow for each hour of the 24-hour day.

So in NoiseMap, you do not enter this as a 24-hour traffic flow. [There isn't any box for entering this value.]
Furthermore, do not divide the flow by 24 and enter this value for each hour of the day.  This is because the flow varies over the day, being greatest in peak periods (rush hours) and less at night.  This is called the diurnal variation. If you do know the diurnal variation, you could factor the 24-hour flow into 24 one-hour values, but most likely you do not have this information.

The usual approach is to convert the 24-hour AADT into an 18-hour AAWT (annual average weekday flow) as this is the value used by the Noise Insulation Regulations (to err on the high side, as weekday flows are usually higher than weekend flows).  You can then enter this value into the 18-hour flow column of the Traffic Flow Manager.

CRTN has a built-in presumption of the diurnal flow variation, based on the 18-hour AAWT flow, and the noise levels are calculated on the basis of that presumption.

So how do you convert 24-hour AADT to 18-hour AAWT?  There is now a lot of traffic data published on various government and local authority web-sites.  Some of these give traffic counts over various time periods, often for specific roads. From these, it is possible to deduce a conversion factor.  For example, on a certain part of the M25, the 18-hour AAWT flow is 95 % of the 24-hour AADT flow. Also, the 18-hour AAWT percentage of heavy vehilces is 94 % of the 24-hour AADT (there is a slightly higher proportion of heavy traffic at night).
These values are typical of motorways.

You could also use this source of traffic data to derive typical conversions of 24-hour to 24x1-hour values, but this generates a lot of data and is unlikely to greatly improve calculation accuracy except where the diurnal variation is atypical - for example, close to a port or distribution centre.

35

Hints and Tips / How can I get high-quality large-size contour maps out of NoiseMap?

« Last post by roger on January 09, 2017, 05:53:57 PM »

An early topic on this forum describes the options for map output, but here I'm assuming that you want high-quality maps of large areas.

NoiseMap has the ability to 'print' scaled maps to any Windows-enabled graphics device. But, except for public display, large paper maps are cumbersome to handle, expensive to transport and a problem to store.

I recommend that you 'print' your maps in PDF format.  These are easy to handle, transport and store electronically and can be easily viewed on-screen.
NoiseMap prints maps in vector format. Each object drawn as a series of outlines, filled with colour as required.  This means that you can view them in any PDF reader and scale them to any size without loss of quality.

For example, I have output a noise map of an area of 12 square kilometers at 1:2500 scale on a 'virtual' page which is 1m by 1.5 m in size. It fills my screen at 20 %, but the houses are no larger than a pinhead.  If I zoom in to 400 %, the houses are postage stamp size and razor-sharp.  I can clearly read the all receiver and contour noise levels as if I was viewing them directly on the noise model - because they are re-drawn at this scale, not enlarged from the smaller scale.  Not only that, the file size is very modest - about 10 MB. The file size of a jpeg  1m by 1.5 m at this resolution would be astronomical. This is the beauty of vector graphics!

You create the output using the PRINT function of the NoiseMap file menu. But firstly, you need to set up a 'pdf printer' to do this. There are a number of ways of installing a PDF printer.  If you have Adobe Acrobat Standard, then this will have set up a printer for you, called something like 'Adobe PDF'. As you can imagine, this is reasonably expensive to buy. A less-expensive system is Win2PDF which works well with NoiseMap, and no doubt there are other cheap or even free systems.  You can usually decide to print to one of the standard paper sizes like A4, A3 or A2, or you can choose a your own print size.

I'm absolutely sure that you will find such a system convenient, productive and impressive to your clients.

36

Support / Can the height of adjustable barriers be different in each scenario?

« Last post by roger on January 06, 2017, 10:53:28 PM »

NoiseMap allows you to define 10 level adjustment layers which you can then apply to any or all barriers.
For example, you could set Level 1 to be 0.5 m, Level 2 could be 1.0 m, Level 3 could be 2.0 m and Level 4 could be 3.0 m.
You can then apply any or all of these levels to any noise barrier. The selected levels are then added to the height already assigned to that barrier.

Thus, suppose a barrier is defined as having a height of 40 m above datum.  If you assign adjustment level 1 to that barrier, a height of 40.5 m will be used in the calculation.
If you assign both adjustment level 1 and adjustment level 2 to that barrier, a height of 41.5 m will be used in the calculation.
If you assign adjustment levels 2 and 4 to that barrier, then a height of 44.0 m will be used in the calculation.

The adjustment levels of a barrier can be different in each scenario.

However, there is only one set of adjustment levels in a model and these apply to every scenario. So if you change the levels of the adjustments, for instance in the above example you change level 3 from 2.0 m to 1.5 m, this will affect the height of every barrier which uses adjustment level 3.  But this will not automatically invalidate any calculation that depends on adjustment level 3.

We therefore strongly recommend that when using adjustment layers, that you decide on their heights and do not then change them once you have started calculations.
If you change the adjustment levels assigned to a barrier, this does invalidate the affected results, thus warning you of potential inconsistencies.

Whilst it might seem a quick solution to change the adjustment level value rather than going through the barriers and clicking on the check boxes, you still need to create a different scenario if you want to save a calculated contour, and unless you are careful to name the scenario carefully, you will not have any record of changes in assumptions so QA will be more difficult.

37

Hints and Tips / How do I unhide a scenario?

« Last post by roger on January 06, 2017, 07:02:11 PM »

You can use the Scenario Manager to do some useful things like changing the name of a scenario or hiding disused scenarios.

If you want to re-use a hidden scenario, you will have to unhide it. Go to Scenario Manager and click the 'show hidden scenarios' button.
This just reveals the scenario temporarily. If you want to see and use the scenario in the previewer, then in the Scenario Manager, click the Unhide button and click apply.
You can then open and edit the scenario as normal.

38

Hints and Tips / How can I speed up the generation of the 3-d view?

« Last post by roger on November 23, 2016, 06:49:48 PM »

The short answer is that NoiseMap only creates a 3-d view from the part of the model that is loaded when you start the 3-d generator, so it will be much quicker to create a number of small 3-d views rather than one large one: in any case, these are usually more convenient to use.

The 3-d view consists of thousands of triangular 'facets' each with its own orientation and surface texture. These have to be generated from the noise model, which only has points and lines representing the objects in the model.  The first part of the process is to work out where the corners of the triangles are going to be placed.  The 3-d generator shows this step as 'Generating Vertices'.  With a big model there can be thousands or even millions of these.

Then the major work starts - that of joining the vertices so as to fill the model with adjoining triangles in such a way that all the vertices are included but there are no gaps between triangles nor any overlaps. Each triangle also has an orientation so that the viewer app knows which way it is facing, to allow the visibility and illumination of the surface to be correctly presented. There is a huge amount of work in creating the facets, because the objects in the noise model, and thus the vertices, are located entirely randomly. This makes it necessary to check every vertex against every other vertex so that the nearest one is found when creating the facets.  Of course, once a vertex is surrounded by facets, it has been 'used up' so it is not considered further.  You will notice that the faceting speeds up as it progresses, for this reason.

The ground surface takes much longer to create than any other part of the model, because there are so many contour points in it.  If you can simplify the contours, 3-d generation will be much quicker.

The 3-d viewer is a fantastic tool for checking and presenting noise models.  However, for quick checks, you will find Cross-sections and View-As-Colour to be very productive tools.
 

39

Support / Can I model the roofline of buildings?

« Last post by roger on July 07, 2016, 11:56:36 AM »

Yes, you can model the roofline of buildings, but it tends to be a manual process.

We understand that you have OS MasterMap, which has the outlines of buildings.  You also have architectural drawings showing the roofline although the roof heights are not available in digital format.

You have already imported the building outlines from MasterMap, but your client is not happy to have the buildings represented as rectangular blocks. 

Two  approaches are:

(1)   Model the roofline of each building using Noise Barrier objects.

Having got the building outlines on-screen, I suggest that you then switch to the ‘add barrier’ mode and trace round the outline of each building, clicking at the eaves and the ridge of the roof, so you can put in the relevant height (NoiseMap lets you have sloping barriers).

As an alternative,
(2)   put the height of the building as the eaves height and then just add barriers along the ridge lines,

This would be less work and would give you much the same amount of screening.  (Remember that CRTN only uses the screening effect of the most effective barrier in combination with the second most effective barrier, and other barriers are ignored.)

You can check what you have done using the 3-d viewer, but remember that barriers are shown as thin vertical panels rather than solid objects, as this is how they are treated in the noise analysis.

40

Support / SiteNoise - How do I set the soft ground effect?

« Last post by roger on June 06, 2016, 05:22:10 PM »

There are two parts to setting the soft ground effect.
The first is to set the Ground Type at the source.  When you enter the 'Fixed Working Properties' (or Route Segment Properties) then under Fixed Working Properties (or Route Parameters) there is a property called 'Ground Type'. This can be set to Hard Ground or Soft Ground.  If you choose Hard ground, soft ground attenuation will be omitted.  You must choose Soft Ground if you want NoiseMap to work out whether there is any soft ground effect.  [As an alternative, you can enter Hard and Soft Ground outlines, which allows variable ground cover to be used, see the User Manual.]

The second part is to select the methodology for calculating the soft ground attenuation.  Go to Parameters>Calculation Parameters and go down to BS5228 SiteNoise  Calculations. Under Soft Ground Correction, you have the options of BS5228:1997, Concawe and CRTN.  The differences are fully detailed in the User Manual, but at a distance of 1 km from the source, typically BS5228:1997 gives slightly less than CONCAWE (which is an oil and gas industry procedure) and a lot less than CRTN (although this may be because CRTN should not be used at long distances.)

Generally, the BS5228 procedure should be satisfactory.

Note that if the source is screened from the receiver, for example by the ground contours, and the screening is more than the soft ground attenuation, then the soft ground will appear to have no effect.

If you want to check the values of each of the corrections, such as hard ground, soft ground and barrier screening, then do a 'live' calculation with the 'one line per segment' option selected. To do this, you need to create a receiver point and then select Calculate>All Receivers from the menu.  This will provide each of the calculation corrections so you can see the effect they have on the end result.