Archive for May, 2010

XMap at Work–Using the Earthmate PN-40 and the ESRI Extension in Historic Global Warming Research

May 22, 2010

Ian D. Browne is a paleontology graduate student at Oklahoma State University Center for Health Sciences studying the faunal response of small mammal communities to periods of intense global warming that occurred between roughly 14.5 and 17.0 million years ago. Before making any meaningful conclusions about these communities, Ian needed to field-check the location of museum fossil sites and previous geologic interpretations.

Several factors complicate this task:

  • The field area in California’s Mojave Desert is topographically complex
  • It has been heavily dissected by faults, which have obscured many of the geologic relationships between the different sedimentary layers
  • Research first began in this area a century ago and in the intervening years, many museums and universities collected large numbers of fossils and numerous geologic maps have been created. Needless to say, accessing and analyzing all of this data is time-consuming.

On his first research trip into the field, Ian was armed with little more than a topographic map and an old handheld GPS receiver, whose limited functionality simply allowed him to determine his location as a set of UTM coordinates.  Due to the topographic complexity of the area, Ian found it difficult to maintain his positional reference on the map, so his first year’s field work was not very productive. Ian needed a better GPS receiver that provided field access to his GIS data.

Back at OSU, Ian built a GIS database for his area of study using ESRI’s ArcMAP. This helped organize and synthesize the years of collected data and maps that have been accumulated by various research and exploration teams. Before his second trip, Ian discovered the Earthmate PN-40 GPS receiver, the latest device from DeLorme. It offered mobile access to aerial imagery and USGS topographic maps downloaded from the online DeLorme Map Library. Since the USGS topographic maps downloaded from Map Library are scanned and geo-referenced versions of the same paper quadrangle maps he had carried during his previous field trip, it was like having a “you are here” dot that he could use to quickly determine his location on the map.  This significantly decreased the amount of wasted time on the second trip, but there was still a disconnection between his field work and his ESRI GIS research.

While Ian was on his second research trip, DeLorme introduced the Earthmate PN-40 ESRI Extension, which proved to be the final piece of the puzzle. This extension generates a raster image of a map view in ArcMAP, which is then uploaded to the PN-40 as a base map. This was an ideal solution for Ian as he was able to generate a single file, which incorporated the relevant GIS layers and provided an extremely useful alternative to the standard aerial imagery or topographic maps. This inexpensive tool provided an easy way for Ian to utilize the work he had performed in ArcMAP in a field environment. Ian also used DeLorme’s XMap to import ArcMAP-generated shapefiles and convert them for direct transfer to the PN-40.

“With the PN-40 I was able to access a hundred years worth of field data and digitized geologic maps,” said Ian after his latest research trip, “All while standing on top of a ridge being pummeled by a cold December wind. Access to this much information on the ground allowed me to quickly assess the validity of previous researchers interpretations, making it possible to do the sort analysis in the field that historically had to be done at the end of the day back in camp, or more commonly back in the lab. Currently, I’m digitizing more maps and can hardly wait until spring when I can get back out into the field with the Earthmate PN-40 and the PN-40 ESRI Extension.”

This type of utility in a small, easy-to-use, handheld device is the sort of thing that could barely have been imagined just a few years ago. The combination of ArcMAP and the Earthmate PN-40 provides a powerful GIS data management tool and field-based access to GIS layers.

For more information on the Earthmate PN-40 and the ESRI extension, visit: www.delorme.com/esri

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XMap Advice—Establishing a central XMap database to provide multi-user connections to GIS layers in a network environment

May 22, 2010

XMap users run the gamut, from large corporations to standalone GIS enthusiasts. The former usually have a well structured I.T. infrastructure to facilitate the central management and distribution of data. The latter don’t need to concern themselves about central data management; their data is locally managed by the SQL server conveniently installed on their hard drive during the installation of XMap.

The target of this article is for those XMap users who fall somewhere in the middle: organizations that are large enough to realize the importance of sharing data among their workforce but small enough to get away with not hiring a full-time I.T. manager. Judging by the calls that are received by XMap technical support and product specialists, this group represents a sizable percentage of XMap users.

Sharing GIS data often involves the simple act of exporting, delivering, and subsequently importing Openspace layers. Under this scenario, each user of XMap is their own data manager and their local version of SQL acts as a single-user data repository.

While the export/import process is a reasonably effective data distribution solution in situations where data is shared on an occasional basis, it does have its limitations and potential drawbacks if layers are continually changing hands:

  • It is time-consuming and inefficient
  • It requires the action of the data host to physically extract the data; if that person is unavailable, others cannot access the data
  • Multiple versions of a particular layer might accumulate in each user’s database causing confusion and possible storage capacity issues
  • Most importantly, edits made by each individual user will not be reflected in other users’ versions of the layer

An obvious solution is to develop a more collaborative working environment in which a single version of each layer is maintained and updated in a universally accessible location. A prerequisite for developing this type of data management model is to have all of the required users on some sort of network. This network does not have to be overly complex and for small organizations, it can be easily set up using off-the-shelf hardware.

Once the network has been established and the required users have been granted the appropriate access, a shared XMap database can be created. For this process, there are two possible approaches:

  • All users can be given access to an existing XMap database on an individual’s computer
  • A new instance of Microsoft SQL can be installed on a dedicated computer or server.

The benefit of the first option is that no additional hardware needs to be purchased and no additional databases need to be built and maintained. The shortcoming of this approach is that it doesn’t solve the problem of accessing data when the owner of the host database is away from the office.

If it is feasible, dedicating a continually accessible computer to act as a central SQL server is a much better approach. How is this instance of SQL installed and how is the requisite XMap database created? Thankfully this part is easy.

As previously mentioned, all versions of XMap include by default, an instance of Microsoft SQL on the same hard drive on which the software was installed. During the installation process, SQL is installed before XMap itself. This version of SQL is freely distributed by Microsoft so there is no limitation or license restriction applied to its distribution. Therefore, the simplest way to install SQL on the server is to insert the XMap disc in an available DVD drive and allow the installer to run the prerequisites. After a few minutes, the installer will ask for an XMap license number at which point, the installation can be terminated using the Cancel button. The XMap-ready instance of SQL remains, in spite of the fact that the software itself was not installed.

Using any connected version of XMap, a database can now be created and access granted to all XMap users. The simplest way to create a database on this new server is to create, import, or copy an existing layer. Instead of adding the layer to a local database, choose New under the Target Database dropdown list, type the name of the server (usually [computer name]\XMap7) and type a database name.

Other XMap users can then access the layers in this database by selecting Manage from the Layers menu in the GIS tab and choosing Other from the Source Database dropdown list. After typing the server name as noted above and clicking the Connect button, a list of available databases on the server will be displayed. Back in the Manage Layers window, the available layers can now be added to the Workspace.

This collaborative environment requires a certain level of workflow management to ensure that multiple users are not trying to simultaneously edit the same records. In such cases, the edits performed by the last user to click the Commit button will be the ones applied to the layer. Thankfully XMap includes several tools to help administer this workflow process.

The Database Manager, which is accessed from a button in the Workspace in XMap, allows the administrator to offer database permissions and assign roles (Server User, Database Creator, or Server Administrator) to each user. It can also be used to initiate the database synchronization process that allows GIS layers to be automatically delivered to the local database on each user’s computer so they can work in a disconnected environment.

The layer Check-out/in process can be utilized to assign data within a specified geographic area to an individual user who can subsequently edit, add, or delete records within the limits of that area. While this data is checked-out, the corresponding area in the original layer is locked for editing ensuring that multi-user concurrent editing is avoided.

If an individual user simply wants a copy of a centrally stored layer to work on independently or to take into the field, the easiest way to achieve this is to create a duplicate version of the layer in a local database. To do this, select the required layer in the Workspace, click the Layers button, click Create, and choose Copy Layer. In the resulting window, make sure the local database is selected from the Target Database dropdown list.

Setting up a shared working environment is not a difficult process for small companies or organizations. For XMap users, the benefit of being able to effectively share data and centrally administer key GIS layers results in a more efficient workflow.

For more detailed information on XMap from the I.T. perspective, read the XMap Admin Guide.

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XMap Q & A—Which DeLorme Product(s) should I choose if I want to gather data using XMap Forms?

May 22, 2010

Anyone who has read recent editions of the DeLorme Professional Newsletter will hopefully be well aware of the data collection capability that XMap Forms enables in the desktop software and on the Earthmate PN-40. At the risk of beating a proverbial dead horse, full details can be found on the XMap Forms Web page. The intent of this article is not to regurgitate the same functional description of the procedure for developing and managing XMap Forms, but rather to outline which DeLorme products are needed to utilize the forms process.

Creating XMap Forms
First and foremost, you need a copy of XMap 7 GIS Enterprise or XMap 7 GIS Editor to create XMap Forms. However there is a caveat. XMap Forms can only be developed in a layer which resides within an Enterprise database, which can only be created using the Enterprise version of XMap. If, as a user of XMap GIS Editor, you have access to such as database within your company or organization, you are all set. If you are a standalone Editor user, you will need to upgrade to Enterprise to create XMap Forms.

If your intended use of XMap Forms entails simply creating forms as a convenient mechanism for adding, deleting, or editing records in your own layers, you need read no further. XMap provides all you need. If, on the other hand, you intend to deploy XMap Forms to your field technicians or mobile workforce, or if you plan on collaborating with other XMap users through the use of XMap Forms, read on.

XMap Forms on the Earthmate PN-40
As previously noted, XMap forms can be used on the Earthmate PN-40 or in XMap. If you intend to use the handheld GPS receiver for data collection, you need to purchase a device for each user. However a single copy of XMap can be employed to distribute forms and any corresponding data to multiple PN-40s and subsequently to upload and manage field-collected records. Typically this process is initiated by individually connecting each device via the included USB cable to the computer on which XMap is installed. Data collected remotely can also be emailed in gpx format to the administrator and manually merged into the master GIS layer.

XMap Forms in XMap Professional
It should be noted that XMap Professional cannot be used to create or manage XMap Forms. Forms created with the Enterprise or Editor versions of the software can be used in XMap Professional. The only way that form-based data collection or editing can be initiated in XMap Professional is through the layer synchronization process. In other words, if you simply export an Openspace layer in which a form has been created, and import that layer into XMap Professional, the form will not be accessible and data cannot be edited in any way. In order to unlock the form, a valid forms license must be purchased for each end-user. This small investment significantly increases the value of XMap Professional by transforming it from a GIS data viewer to a field data collector and editor.

XMap Forms licenses are administered through the Database Manager, which also controls access to synchronized layers for each user. A company will typically purchase a forms license for each copy of XMap Professional, however it is also possible to reassign a license to a different XMap user, which in turn will disable the forms functionality for the original user.

To summarize, XMap Forms functionality in XMap Professional requires a copy of the Enterprise edition of the software to establish synchronization and to create the form, a copy of XMap Professional for each end-user, and a forms license.

XMap Forms in XMap GIS Editor or XMap GIS Enterprise
Unlike with XMap Professional, layers containing XMap Forms can be manually shared among users of the Enterprise and Editor versions of the software without the need for synchronization or a forms license. If a layer containing a form is exported in Openspace format, this layer and the accompanying form will be available to anyone using XMap GIS Editor or Enterprise.

XMap Forms provides a user-friendly facade for your GIS layers and significantly simplifies the process of remotely collecting and editing GIS data. In certain instances, XMap Forms can be used right out of the box. If forms capability is to be utilized by a remote workforce make sure you include the required forms licenses in your purchase.

For more information and pricing, visit www.xmap.com/forms or call 1-800-293-2389

Posted in XMap Q&A | Leave a Comment »

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