4.24.2012

Free and Open Data Reliability : The case of Open Street Map road data vs "PAID" data sets

This is the very typical example why the people in our country should free our data!


Shown above is a map of my road data for a hydrologic model. Two unaligned road networks are visible from the image above. The red lines are my initial datasets which are actually "PAID" dataset from a government agency. When I did an overlay with a pan-sharpened satellite image, I got a large shift from the actual road network visible in the image itself. My initial notion is to georeference the image so that it would fit the readily available road data. However, when I tried overlaying the location of my mapped inlets, I noticed that the storm drain network which is aligned with the road coincides with that of my backdrop image. These inlet locations are in-situ observations gathered from a week of fieldwork hence there must've been a BIG problem with my road dataset. My next solution is to look for a free dataset. I have tried using Open Street Map data and alas! OSM data has a better fit! The yellow road network above which tends to coincide with the blue network of dots is actually the road data from Open Street Map. See how great and more reliable those FREE and OPEN datasets are?

Of course there may be some risks in using these free datasets but for my purpose, the OSM data obviously provides a better accuracy as compared to the "PAID" datasets that we get which are highly erroneous and on the first place.. shouldn't be PRICED at all!

I think our government should somehow consider this example. There's no harm really in opening our data to the public, the limitations should by far be set properly though.

With free and open data we get a WIDER COMMUNITY to do the refining for us. The blunders are fixed through time and we get something that's FREE and USEFUL and MORE RELIABLE for our ancillary datasets that would soon build a a more seamless layer overlay and analysis in our own geographic information system.

4.23.2012

How to choose a course for college and get a career after graduation



A few weeks ago, I was asked to give a short talk to a few young people about some wisdom on choosing their college course or future career. Since I haven't gone into the industry and had much of my time spent on research, I preferred taking the college course guidance part and leaving the industry and career after graduation part to my husband who has gone farther than me in terms of employment and experience of course. 


So for me, I made this analogy: Choosing your college course is almost the same as choosing your next faithful pair of shoes!
  1. Your choice of shoes should fit your budget and so is your choice of college course. - Have a reality check. You might be wanting the most expensive shoes and yet you know you can't afford it just yet. You may try your way by working harder while studying to earn your dream degree and yet end up not finishing it because of deeper financial constraints. So you better be real earlier or end up in regret of an unfinished dream.
  2. You will be the one to wear it so you yourself should love it. - Be passion driven. Know what you love doing the most and start from there. Your hobby may not necessarily bring you more money but later on in life, when you get to choose your respective jobs, you wouldn't want to get burned out because of a job that pushes you to death simply because you don't find enjoyment in doing it but you just want to earn big bucks for it. Mind you, loosing a job is more bearable than loosing your smile. 
  3. You will invest money, time and effort and choosing it so you better get the best pair that will fit your needs. - What are your priorities in choosing a course or career? Do you want to earn more money or do you want to improve your skills and doesn't really care if you earn or not afterwards? You set your standards and choose the course that will best fit such yardsticks. Choosing an inexpensive career from a vocational school on being a "barista/ bar tender" and then getting into a well-known hotel or cafe is more rewarding than finishing an expensive nursing degree ending up as a call-center agent after graduation.  
  4. You will use it for long so it must be sturdy and can withstand the test of time. Make sure you buy a tried and tested brand- Do your homework and research for the best institution offering your career of choice. The school may not be the real determinant of your success but it will surely pave you the way. Just as you may be needing or learning far more than what you've learned from the four corners of your classroom when you get into the industry, graduates from the best schools always have their edge.
  5. You wouldn't want to have so many other people wearing the same shoes as yours. - Don't take a course just because it's IN. Four or five years from now, that employment boom today may no longer be that in-demand as it is. You wouldn't want to compete with others in terms of employment afterwards or worse, you wouldn't want to be underemployed afterwards and not having the chance to practice your honed skills simply because there are no enough jobs for all of you graduates of that course. If you can, I fervently hope you will... please don't ride at the BANDWAGON of unemployed/ underemployed after graduation. 
  6. When everything else fails and you feel like you ain't got a choice at all, TRUST THAT GOD WILL GIVE YOU THE BEST PAIR! - I have my own gauge of divine intervention. If I got an opportunity smoothly, almost without lifting my fingers, I know it's God's will. Do your best in choosing your career but make sure  you keep the balance between all aspects - social, physical, intellectual and spiritual most importantly. I was once a stranger to this Geomatics field. I never even knew such course exist but I knew God placed me in here to make a difference. It's the divine intervention that made me push through and eventually love the field that I am into right now.  I would always think that GOD GAVE ME THIS and HE has a plan for me... of that I'm SURE! Of that I'm SURE!
And one last word and I think this is as important as your choice of career. Remember that the moment you get there ...    "Whatsoever thy hand findeth to do, do it with thy might." (Ecclesiastes 9:10)

Always give your best shot and develop into the dark room where you're processed. Plan your flight path, map your future and build a GIS of your dreams. #graduatesROCK-ON! 










4.12.2012

Why such a big deal with the rocket launch in North Korea?

North Korea's much hyped rocket launch has failed today, April 13, 2012. For the past few days, or even weeks, there have been much-a-do-and-say about such "overrated" launch. Most countries, especially the first world, are having debates on such move by NoKor.

Reuters reports:
"North Korea said it wanted the Unha-3 rocket to put a weather satellite into orbit, although critics believed it was designed to enhance its capacity to design a ballistic missile to deliver a nuclear warhead capable of hitting the continental United States."
So, is that it? Is North Korea already that powerful to wage war against those first world countries?

The paranoia has reached countries within the flight-path of such North Korean rocket including the Philippines. And since we are not capable of shooting such debris from the sky, removing it from its trajectory and totally crashing the rocket parts as it enters  the Philippine area of  responsibility, we were just advised to refrain from going out on some specific time of the day when the rocket would supposedly pass by our country. What do you think?

I would often wonder how the people could've  reacted to the Japan's launch of Spy satellites in 2003? Or how about the 4000++ satellites launched since 1998?

Wisegeek also says:
 "There are approximately 3,000 satellites operating in Earth orbit, according to the US National Aeronautics and Space Administration (NASA), out of roughly 8,000 man-made objects in total. In its entire history, the SSN has tracked more than 24,500 space objects orbiting Earth. The majority of these have fallen into unstable orbits and incinerated during reentry. The SSN also keeps track which piece of space junk belongs to which country.
As of 2008, the former Soviet Union and Russia had nearly 1,400 satellites in orbit, the USA about 1,000, Japan more than 100, China about 80, France over 40, India more than 30, Germany almost 30, the UK and Canada 25, and at least ten each from Italy, Australia, Indonesia, Brazil, Sweden, Luxembourg, Argentina, Saudi Arabia, and South Korea. "
Spacenews even reported some 10 year forecast that:
"According to the annual forecast of global launch activity the consulting firm released Aug. 25, an estimated 1,145 satellites — worth $196 billion worldwide — will be built between 2011 and 2020. About 70 percent of the satellites can be attributed to government demand, Euroconsult said."
Those satellites, just like that of South Korea, were of course rocket launched. But why make an argument on a single-failed attempt to stop a satellite launch just now?  Just so it may have been disguised as a ballistic missile test? But what about those countries who have just launched their own rockets some few years back?Why make much a fuss about a weather satellite from a relatively newcomer in the space-technology-era?

Since retrieving a broken satellite from space is more expensive than launching it, the satellite-space junk is continuously increasing through time thus creating a SPACE POLLUTION so to speak. Just as there are already a number of operational and non-operational satellites and space debris on the earth's orbit, these seemingly-fictional space junk image must've been really turning into a reality.


 Just as our sky's NO LONGER the limit anymore and there are already thousands and tons of space junks already in orbit on our precious mother earth, why trouble ourselves much with the worry of a fail attempt to launch a "weather" satellite JUST NOW? Maybe the delayed reactions are already too late, or maybe too, it may just be in time.

4.02.2012

Off-the-fieldnotes: On fieldworks using Handheld receivers

Last week was one tedious week, part of my primary data gathering is to map all the storm drains within my study area for my thesis. That was about 371 hectare area of land with a mix of residential, commercial and industrial land uses. I have used 2 types of Garmin Handheld receivers for this part, the Garmin Oregon 550 and the Garmin 76CSx for this storm drain inventory and mapping field work.


I would say that both are pretty good in terms of accuracy for a handheld receivers with a purpose of mapping  features just for reconnaissance or coarse accuracy requirements. Here are my rants/raves two cents for fieldworks utilizing handheld GPS receivers i.e. GARMIN GPSmap 76CSx and Oregon 550.
  • Do understand the primary purpose or objective of your data gathering and use the right tool for such purpose.-  You can't use a handheld GPS receiver to plot the corners of your lot and use it as an evidence for a land grabbing case. Have a clear understanding of the capabilities of the GPS device that you are using. The handheld GPS are of  the lower accuracy type with an accuracy buffer of 10-30m so if you are, for example, trying to map all the trees within the neighborhood or for my purpose map all the storm drains to locate inlet locations for my flood simulation, the accuracy of a handheld receiver is already sufficient. 
  • Use Alkaline batteries if rechargeable NiMH batteries are not available. - As you may know, GPS devices are power hogs. This is the major reason why your iPhone drains faster than usual when your location services that utilizes GPS are turned ON. So for your purpose of mapping, if you've got one large area to cover, better make sure you have lots of spare batteries at hand. Based on my experience, the Alkaline batteries (Energizer) lasted for 8 straight hours for the Garmin GPSmap 76Csx while it only lasted for almost 4 hours for Oregon 550. The longer performance of the 76CSx would be understandable since it doesn't have a camera that uses up much power unlike that of the Oregon 550. On my first day, I have used Eveready but to my dismay, it only lasted for 2 straight hours of mapping so I have to readily change batteries which is very much of a hassle. NiMH are also good choices for it lasts about 5 hours for the Oregon 550 but you still have to bring spares for longer mapping works.
  • Make sure to immediately save all your data gathered when you come back at the office. - This is my HARDLY LEARNED lesson . I have tried Oregon 550 first and since it has a support for memoru expansion, I didn't have worries for memory shortage. To  my dismay, the GARMIN 76CSx can only save up to 1000 waypoints. I am an hour before my last 3 kilometer stretch for the week-long fieldwork and I already ran out of waypoint memory. Too bad, I can't delete the previously gathered points :(. So unless you have a laptop onfield to readily save your data, better make sure to have it backed-up and deleted on the GPS receiver memory to allot more space for your recent observation points. For me, I have installed the MapSource program to receive and upload data from my computer to the GPS device. It has an option to save your data in GARMIN database, GPX (GPS exchange format), and TXT format for further processing :)
  • Plan your route ahead. There is indeed no better substitute to a carefully planned fieldwork. It would definitely save you much of your resources- time, money and effort. Just as there may be slight deviations from the original plan, plannning ahead is still the best way to commence every field data gathering exercise.
  • Lastly and Again know your device before going on field! - Part of the carefully planned fieldwork is a thorough knowledge on operating the device that you are going to use. Familiarity is the key. For user-friendliness, I like the Oregon 550 more because it's already in touch-screen interface as compared to the 76CSx which is still operated by button. I never really had a hard time getting used to Oregon 550 but the 76CSx is a whole new different story. I don't know if it's just me and my stupid nature that took me an ample 2 hours to figure out how to mark waypoints using the GARMIN 76CSx. So for the record, HOW TO MARK A WAYPOINT USING GARMIN 76CSx, Just long press the ENTER button and there you have it! (^_^)  The deleting of waypoints and tracks are also harder ones or I guess less intuitively designed ones. You can figure it out by pressing the menus over and over again. So yeah, FAMILIARITY IS THE KEY! So don't hesitate to explore your devices first or you'll have the entire day out on field exploring on how to use it...
  • Oh no, beforeI forget...In case you ran out of space for waypoints in your Handheld GPS and you still got a phone powered by GPS (that's not yet on a low battery!) ... you may opt to use it for mapping purposes too! I seemed to have been really frustrated when I ran out of waypoint memory and forgot to use my HTC Mozart which is also capable of geotagging photos. So yeah, for my next field mapping work, I would be very much reminded of using my usual buddy for my location-based needs:) Since our modern smartphones nowadays are already GPS powered, it works pretty much like our handheld receivers with Assisted GPS (AGPS) capability. This AGPS utilizes the location of the nearest cellsite to easily "assist" fix your position. Very nice indeed. This is a photo taken from my fieldwork for which I have turned on the location option everytime I take photos. When I tried geotagging it in Picasa, it appeared to be about 10m off the original location as specified by the Handheld GPS which is fairly ok for mapping purposes. 


Just are there are no fast rules, I hope this helps and I'm sure I'm getting more of these hardly-learned lessons that I will gladly share and chronicle here in my blog in the days to come...just so until I'm done with my data gathering part of my thesis  #fieldworkIsMoreFun (^_^)