Class Reflection

I want not sure what exactly to expect when I signed up for this class. I only knew BIM so far as that Revit was a part of it somehow. Even after the first day when Prof. Mitchell told us what to expect in the class, it still turned out different then what i thought. This class turned out to be one of the most interesting classes as the variety of things it covered was surprisingly vast.

The class started as one might expect, talking about buildings and what goes into making them. However the class quickly went into a more 'what if' mind set instead of talking about what is currently the standard. This aspect of the class made it much more interesting than any other class I have taken so far. Looking at what the future could hold for out profession was fascinating.

While I'm sure a couple people got a little bored by the database information, I personally really enjoyed that portion as I am always striving to increase my computer/programming knowledge. This is the portion of the class I was also least expecting, why would AE/CIVE/ENVEs be doing database stuff? However it was quickly shown through the speakers and by in class discussion how the tools we really on the most, AutoCAD and basically any computer drawing program, are all just advanced databases.

The professional speakers brought in through out the course also helped provide some real world context to what we were talking about in class. This was especially helpful in some of the topics that were unfamiliar such as the use of augmented reality programs and how involved databases are.

The new things I learned in this class were Revit families and basic database information. The Revit families will be a very useful skill through out my career so getting a start on it now was very useful. While the database exercise was interesting, I am not sure how useful it will be to be in the future.

Like many of the other students have been saying, 10 weeks is not quite enough time to cover all the information this class could present. However I believe professor Mitchell is taking this into consideration and making a whole AE concentration based on digital buildings which, from my understanding, would have whole courses based to Revit and databases, things we covered in a couple weeks in this course.

I actually completely disagree with David Morrison when he talks about the assignments piling up. Other than the project which we had more than ample warning would sneak up on us, I did not think that the workload was that bad, I actually find AE 391 to be a busier course; a blog post every week is certainly easier than a whole website every week Then again, maybe, thanks to Drexel, I have become desensitized to a heavy work load.

Course Reflection

My expectations  for this course were to learn about the concepts behind BIM and some of the emerging technologies in the industry. Furthermore, I was hoping to gain a better understanding of how buildings are monitored over their useful life. I certainly feel that all of my expectations were met at some point in the short ten weeks we had to discuss intelligent buildings. In fact, in many ways, my expectations were exceeded in this course if only by the quality of discussion and personal interest in the subject matter. As David Morrison reflects, the topic of “Intelligent Buildings” is an exciting one, especially for architectural engineers such as myself.

What felt like the course introduction, in the first two weeks, served to whet my appetite for the lectures to follow. I found the lectures given by representatives of Revit and Bentley to be particularly interesting, and useful as an overview of what these two modeling programs are about. Learning that databases are responsible for the operation of these programs made me more willing to investigate database design as we were assigned. Not only was I willing to learn, I found our discussion of databases to be extremely intuitive and edifying, especially having no previous knowledge about databases. I agree with John Scanlon that the overall format of this course is clear and informative, even for the most basic level of understanding. I further agree with Elda Cifligu that I got out of this course what I put in.

That being said, my only difference of opinion with the format of this course is the relative time spent on databases. I felt that the initial introduction to databases and the following tutorial, in conjunction with the excellent online tutorials, was more than sufficient to develop a basic understanding of databases. I would have preferred to see the second week dedicated to databases spent on further development of our term projects, or some other aspect of intelligent building (sensor use comes to mind). Other than this, I felt the work assigned was fair in its magnitude and its timing. I appreciated the checkpoints on our term project and the fact that it was due a week before the madness of Week 10 set in.

In general, the tenor of this course turned out to be far more interesting than I expected. By maintaining an overview of the topics we explored, and just enough technical detail to get our feet wet, I felt the course remained fresh and exciting for the majority of the time. I’ve always enjoyed the format of the courses conducted by Professor Mitchell, but I found the content of this one to be particularly interesting and useful. It would have been futile to attempt to teach an in depth course on all the topics covered in this class, and there are plenty of technical courses worked into my schedule already. This course was a refreshing break from the technicality of my other courses, and an eye-opening introduction to larger (arguably more important) concepts that I will be facing in my future as an engineer. In short, I felt the level of detail in this course was perfect, and the content useful for focusing my attention on relevant issues in the engineering world today.

Class Reflection

AE 510 was an illuminating class. In fact for a novice like me, in both database technology and BIM, this class opened new doors to solving engineering problems. I found that Professor Mitchell’s formatting of this class was simplistic to the point where novice users of BIM and database software could acquire basic skills in the aforesaid areas without being confused. I have tried to take database courses at a community college and found myself quite confused due to improper communication from the teacher to the student. Professors Mitchell’s tutorials were excellent in helping one learn how to use Microsoft Access. I also found that his tutorials on BIM were most beneficial. I can honestly say that, even though I had no prior experience with BIM, that I am leaving this class confident that I can use BIM’s basic functions. This is a big resume booster.

Elda Cifligu makes a valid point that it is impossible to cover the broad spectrum of “Intelligent Buildings” in one ten-week course. I agree.  However, I believe the intention of the course was not to produce experts of intelligent design, but instead to open the door to the concepts. I found that Professor Mitchell’s approach to this class was quite ingenious; covering a wide variety of topics from robotics to sensors while providing the students with basic software savvy.

I disagree with David Morrison’s idea on grading. The measure of a class’s worth should not be a degree on how easy it is to get a grade, but rather how much one learns in the class. I can say from experience that I have had classes where I have labored for hours trying to walk away with a decent grade and found that my knowledge fell short (even though I got an A). On the other hand I have had classes with minimal assignments and very easy tests and found that I have superior knowledge on the subject. This class provided me with exactly what it had promised. I left with a basic awareness of Intelligent Buildings while gaining a fundamental knowledge of BIM and Access.

Course Reflections

I can certainly say that AE 510 exceeded my expectations. When I signed up for the course I thought that we would just talk about the main concepts of intelligent buildings and BIM, but there were many more subjects covered in these 10 weeks. The interesting part was that these subjects were new to me or hadn’t worked with before. For example, the database assignments were very interesting because, not only I learnt how to develop one, but also the different applications databases can be used in - I had never thought that I would use databases to help conduct my work. I really enjoyed the fact that this course is interactive and that we each learn from each other. I learnt a lot from the guest speakers that visited throughout the term. Their presentations were enjoyable and interesting.

However, I think that 10 weeks is not enough to cover all the concepts mentioned in AE 510; sometimes I felt rushed due to the amount of material presented in this short time. I wish we had concentrated more on fewer concepts that are more relevant in my opinion, for instance BIM softwares. If I had one or two more weeks dedicated on BIM, I would probably try and develop a more complete drawing, or I would attempt to integrate families. Additionally, as Maria mentioned in her blog, it would be extremely helpful to have all the assignment descriptions and requirements in one folder/location instead of multiple ones; it got complicated sometimes for no reason.

Overall, I believe that this course was very beneficial.

AE510 Reflection

I expected one of two things coming into this course, that it was going to be a BIM class or that it was going to be a class similar to the 390-391 series only on steroids.  Much to my surprise it was neither of these two.  For that I am glad.  I took the course because it sounded interesting but it was also one of the few graduate level courses that were offered this term.  Therefore, for it to be similar to my other classes would have been monotonous. 

All in all I found AE 510 to be a little disappointing.  I feel that for a graduate level course I didn’t really take out as much as I would have hoped.  I feel that we, as a class, just skimmed over any topic that was covered.  I understand that the large amount of material covered and the short 10-week terms makes it next to impossible to go in depth on any one specific topic without excluding another.  It would be nice if this course could be broken up into a two course series.  This would give the class 20-weeks to cover certain topics in much greater depth.  Several topics that I would like to have gone in more depth are artificial intelligence and robots in the construction industry.   

Several projects that I liked throughout the term were creating the family in Revit, and the database project.  These two projects dealt with topics that I had never covered before and I feel that they will be beneficial in the future, especially the database knowledge.  Modern day society is so dependent on databases that even a minor understanding can be extremely beneficial.  Knowing how to create families in Revit can also be very helpful in the professional world, although, I hope to never have to make one because it was somewhat annoying setting up all the parameters and relationships.  But it’s better to know and not need than need and not know. 

Alvarado notes that the guest speakers were a great aspect of the course.  I agree with the statement, “Every single guest speaker was very well chosen because they were all able to contribute with their insight at a topic we were covering.”  However, I don’t agree that every guest speaker was worth having.  I believe that Hue Robert’s Lecture was very well done; it gave me hope for the industry and the growing figures in infrastructure.  I also very glad to have Travis Peyton come speak with us.  He’s a man with great enthusiasm that can get anybody interested in engineering.  His talk on increasing building efficiency was very informative and worthwhile.  I did not think that Dr. Il-Yeol Song’s lecture was that beneficial.  It’s nothing against Dr. Song, his lecture was informative, however, a lot of the material that was covered had already been covered the week prior.  For example, he dedicated several slides to the one to many, many to many relationships that we had already discussed.  He also discussed SQL in depth, which we never used afterwards. 

Both Jeanine and Kayleigh mention the importance to stay up to date with technology.  This class was very beneficial in that scenario.  The topics covered are the up and coming topics in our field and to have a base knowledge, as stated before, is very beneficial, especially, upon entering the workforce.  Jeanine and Maria also reiterate what Professor Mitchell said at the beginning of the term, that it is easy to get by in this course but to get anything out of it the time must be committed.  I do take responsibility for not putting in as much effort as I would have liked.  I do think I could have gotten more out of the class by working harder.  I tell myself every term that I’m going to be a good student and do everything early so I have plenty of time to study and do projects, none of which ever happens.  

Reflections on Intelligent Buildings

Overall, I really enjoyed this course, if you are an Architectural Engineer and the course title "Intelligent Buildings" doesn't excite you, than you might be in the wrong major (I know this course had to serve other majors as well). I think this course did a good job of living up to its exciting title.

I think Maria and Jeanine pointed out the biggest issue students (including myself) had with the class, which was that the assignments sometimes piled up very high on each other. This was sometimes a pain to deal with (I can imagine that is was just as a pain to grade in a timely manner). However, this class IS a masters level class for many students, and should be more rigorous than an average undergraduate class. I did not find the work in class to be super challenging, however the class still turned out to be a handful with the amount of work that needed to be successfully juggled, which provided the master's level rigor which requires students to have discipline to successfully complete. Everyone likes an "Easy A" class, however in a 10 week term, it is sometimes very hard to successfully learn a large amount of material without it being speedily thrown at you (just like in the real world).

I also agree with many of the other students that suggest that this course is one that you really get out what you put in. For my project, my partner Tom Ben-David and I decided to build a sensor network from scratch and then wrote a paper on the use of the sensors in a multi-sensor room. This was admittedly biting off a little more than we could chew, and we got the paper written very close to the deadline due to the time it took to actually build the sensor network (even missing some features we wanted). However, the process was very rewarding, and I feel like I got a lot more out of the project than writing a strictly research based paper.  I felt the same way about many of the other assignments in the class such as creating a report for my database that included graphs really pushed the envelope on the scope of the project and added tangible skills to my resume and skill base.

Zombie Emergency Response Center

Group B - Building Story

Our building is an emergency command center located in Washington, DC. It is specifically designed to survive all major emergencies, up to and including a major zombie apocalypse.

This building will be built in 5 years from now in (2018), and will implement all of the latest building technologies we have discussed in this class. In the programming and design phase, the entire design will be completely started and executed using BIM. This will allow everyone in the process, from architects, and engineers to contracts and maintence personnel to use the BIM to show useful data that they need. During the design process, 3D models will be built to demonstrate to the owners of the building (government officials) what the buildings current progress looks like and to successively show its zombie proof design.

The bidding part of the project will implement database technology. This will consist of forms being created that will allow the contracts to bid on the different parts of the construction and then these bids would all be automatically saved in the database, and then available for easy comparison by the owners. This project will also require the contractors to be comfortable with BIM so that they can use models in the field.

The construction will be done by Robots. This will induce a high cost to the building, however this is important due to the impending zombie invasion. Strain gauges will also be used during construction to make sure the robots do not add too much load to any part of the building during construction.

The maintenance, of the building will include BIM models across the building to accurately navigate the building in the event of a panic. A database will be used to save all mechanical data, so in the future savings can be found, and major and minor parts of the system can be post-processed to find energy saving techniques that will allow the building to last long after the power goes out to the rest of the city. The database would also include the zombie attack information for future analysis on what the zombies "undead" load is.

The renovation would include the reconstruction after the zombie attack. This will heavily use the existing BIM model that was created during the design. This will allow for changes to be made quicker, and more accurately.

The demolition will include the collected implosion of the building. The building will implement recyclable materials that will be collected by robots to restart the world in the event of the zombie Apocalypse. Sensors will also be used to make sure no particulates are spread too far into the atmosphere, as the new world, will be a great and green world.

Link to Presentation:

https://docs.google.com/presentation/d/1pPifRRbpV6U1EHNyye_2B2AKBL9BUILRON8XwMynAcw/edit?usp=sharing

Temperature Sensors - Thermocouple

As the other groups mentioned, resistive temperature detectors (RTD), simple mercury thermometers, and more technologically advanced infrared sensors are all used to sense temperature. I would like to discuss a different type of temperature measurement – thermocouples. As Elda mentioned, thermocouples tend to be less accurate than RTDs, but they are still widely used in industry. They are simple and easy to understand. They have some advantages too which include a wide temperature range, robustness, rapid responsiveness, and lack of self heating.

Like most scientific inventions, the thermocouple was invented by accident. An Estonian physician accidentally discovered the ability to sense temperature by the effect of joining two different metals together. When two different metal wires are joined together and a temperature difference exists along them, they generate voltage, which is indicative of the temperature difference. Figure 1 presents a simple thermocouple diagram: the junction where the metals meet is called the measurement junction, or the hot junction. That point should be exposed to the temperature we would like to measure. The wires should then be placed in what’s referred to as the reference junction, or the cold junction. At that point the wires are generally inserted in a bath of ice water to maintain a constant 0 degrees Celsius. Thermocouples measure the relative temperature between the two junctions, and therefore the reference junction must be known, and is usually kept at 0 degree Celsius.

Figure 1: Thermocouple Diagram

The metals used are indicative of the sensitivity, temperature range, and voltage range measured by the thermocouple. Table 1 has this information about the common types of thermocouple. The types also indicate the error in measurements. As mentioned before, the error in measurement can be significant when using thermocouples. Figure 2 shows the possible error for four different thermocouples for the temperature range of 0 to 400 degree Celsius.

Table 1: Types of Thermocouples

Figure 2: Error in Thermocouple Measurements

What is actually measured when using a thermocouple is the voltage created by the difference in temperature. In order to interpret this date, one needs to know how to convert the voltage data to meaningful temperature data, which is, again, dependent on the type of thermocouple. The seedback coefficient is the voltage change per degree Celsius in μV per degree Celsius, and it is represented in Table 2 for the different thermocouple types at 25 degree Celsius. The seedback coefficient is not constant, though, which makes the fitted graphs used to interpret the temperature nonlinear. Software needs to collect the voltage data and have a function imbedded within it used to convert these measurements to useful temperature data.

Table 2: Seedback Coefficient at 25 Degree Celsius

References:

http://cds.linear.com/docs/Application%20Note/an28f.pdf

http://www.analog.com/library/analogDialogue/archives/44-10/thermocouple.pdf

Infrared Thermometers

Mike does a great job summing up a wide variety of temperature sensors.  Back in high school I learned that the bimetallic strip was used to control thermostats.  The expansion of the metal at a specific temperature would close a circuit, thus turning on/off the HVAC system.  Now we have NEST, which is more accurate and efficient. 

I would like to expand on Infrared (IR) Thermometers.  These thermometers are essentially a laser gun that can read the temperature of an object without any contact.  This type of thermometer is has an increasing popularity in the food industry.  Chefs are using them to read the temperature of food so that they don’t have to puncture the food and because it gives a fast and accurate reading. 

Every object emits an invisible infrared energy.  IR is located on the electromagnetic spectrum between visible light and microwaves.  There are three ways to transfer this invisible heat: reflected, transmitted, and emitted.  The emitted energy is the only type of energy that can be used to get the actual surface temperature.  This is a disadvantage to this type of thermometer.  As I mentioned before this thermometer is becoming popular in the food industry.  If the food is under a heating lamp the temperature measured will also include that of the lamp.  Therefore, when taking the temperature of the food it should be in low light, or the light should be covered with a cloth.

 

Depending on how advanced the IR thermometer the emissivity value can be altered based on the material.  These values can be looked up in charts.  As a comparison, emissivity of aluminum and water are 0.77 and 0.95, respectively. 

Again these thermometers are growing in the food service industry. They are also great for monitoring equipment.  For example, they can be used to find hot or cold spots detecting leaks in HVAC equipment. 

Sources:

http://www.allqa.com/IR.htm

http://www.thermoworks.com/emissivity_table.html

http://www.buzzle.com/articles/laser-thermometer-how-does-it-work.html

Thermography

I think that Mike did an excellent job of going over the history of temperature sensors and how they work. When I was assigned this post, I immediately though of a thermistor, however it is important to think about the history of temperature sensor, and that the analog approach has worked very well for a long time. I personally got very interested while reading Elda's post when she talked about the use of infrared thermometers. Elda talks about how infrared thermometers are used to detect temperatures without the need for surface contact. This brought me to the idea to discuss thermography as a type of "temperature sensor."

A paper written by Maldague shows there are two main types of  thermography, passive and active. These two types of thermography are discussed as a means of Non-Destructive Evaluation Techniques (NDT). The idea behind active thermography is to send a wave of energy (in the form of heat), and see how the heat moves in the observed medium. Passive thermography on the other hand uses energy already found in the observed medium such as the difference in temperature of a pipe or electric box that generates or takes heat to show how the materials around it act. Thermography can easily be used to determine if an electrical box is overheating and needs attention. It can also be used for firefighters to determine what is going on in a household in the event of a fire, and where people are located inside the burning structure.

The most basic description of thermography, is the use of an infrared camera to detect the radiation from a given material, that then is translated to a surface temperature. It is important (according to NDT sources) to know the emissivity of the material observed to get an accurate reading of what temperature is being observed. If the wrong emissivity is chosen, than the entire process of thermography can become a fruitless exercise.

One can see each different way of measuring temperature has its pros and cons, and there is no one solution fits all approach for measuring temperature.

Temperature Sensors

    A temperature sensors are devices that measure temperature of a medium. As Mike S. mentions in his blog, there are many types of temperature sensors used from simple home purposes to extremely accurate and precise scientific uses. Thermocouples, resistive temperature detectors, infrared thermometers, bimetallic devices, liquid expansion thermometers, and state-of-change devices are the some of the basic types of temperature sensors used for simple or more complex purposes.

    As Mitchell Butler and John Scanlon mention in their blogs, the most basic liquid expansion thermometers, especially mercury thermometers, are the most common temperature sensors that is very easy to use and accessible to everyone. The main elements of the liquid expansion thermometers are the mercury-in-glass sensor which expands and contracts when there is a temperature change and the means of converting this change into a temperature reading. Although accurate, mercury-in-glass thermometers are delicate and mercury is a hazardous material.

    Resistive temperature detectors (RTDs) are the most common sensors used in laboratory and industrial purposes. RTDs use resistors to record resistance values as the temperature changes. They are very accurate and have a wide temperature range which is why they are used for heavy duty purposes. They are preferred over a thermocouple or a thermistor sensor because of their high accuracy and stability for many years.

    Infrared thermometers are non-contact temperature measurement devices that detect the energy emitted by the medium and convert the energy factor into a temperature reading. Infrared thermometers are very useful for temperature measurements of moving objects, or when non-contact measurements are required due to hazardous material; more conventional thermometers do not seem useful in situations like that.

    As mentioned above, temperature sensors are used for multiple purposes. One use of distributed-temperature sensors is to measure the temperature profile of oil reservoirs, which has been done for many years now. The information provided by temperature sensors are very important for the process control of the oil tanks; they provide visual data to optimize the well performance as well as detect flow and viscosity behind the reservoir casing. Nowadays, there are many temperature sensors used in HVAC systems of  buildings in order to efficiently maintain comfortable indoor conditions.


Sources:
http://www.omega.com/prodinfo/temperaturemeasurement.html

http://www.omega.com/Temperature/pdf/RTD_Gen_Specs_Ref.pdf

http://en.wikipedia.org/wiki/Infrared_thermometer

http://www.accessscience.com.ezproxy2.library.drexel.edu/content.aspx?searchStr=Temperature+sensors&id=YB980600

Temperature Sensors

While initially, sensing temperature may seem like a simple concept (and it's been getting done for a very long time now) the actual details of what we are sensing can become quite confusing. In its most basic sense, temperature is a measure of the movement of molecules within a body of matter. That matter can be solid liquid or gas, and more frequent movements translate to higher temperatures (with absolute zero at the bottom of the scale, meaning no particle movement at all) The reasons we care about temperature are varied, but mainly we want to be comfortable or we want to ensure that a certain process is happening by manipulating the temperature. Of course our perception of comfort is based on our own sensing of temperature by biological processes far more complex than the processes we use to quantify temperature.

Obviously the thermometer is the simplest way to sense and understand temperature. We figured out pretty early on that certain fluids expand when they are heated, so that their volume is a function of temperature. By controlling and marking this expansion of volume we were able to quantify temperature. As John points out, we were later able to recognize the same principle applies to solids, and we began to use this to control the movment of thin metal strips, which would in turn control some basic circuitry, mainly for switching on and off some electrical process. Of course, this is the principle by which most early thermostats operated.

As we progressed in knowledge of electrical properties of materials, it was found that the resistance of certain conductive materials decreases as we increase the temperature, and so we developed thermistors made of ceramics or polymers to effectively convert a change in temperature to a change in resistance that could be easily measured. We also knew that the current changes between to metals at different temperatures, so a slightly more complicated Thermocouple circuit was developed, where this change in current can be measured across dissimilar metals. Furthermore we found that different metals behaved more predictably for certain temperature ranges, so a number of sets of metals were used for varying applications. Finally, the resistance in a coiled wire was found to be more accurately measurable, so RTD's (made of a homogeneous wire wrapped around a ceramic core) became prominent. These could be configured differently to accomodate different temperature ranges and provided high accuracy and repeatability.

Mike does a great job of explaining the usefulness of all of the sensors mentioned above. However, there are still some applications in which even RTD's and Thermocouples cannot be used. For example measuring the surface temperature of an object that is moving or one that cannot be disturbed becomes quite difficult with the sensors mentioned above. Rather than measuring a change in a specific material's response to a temperature, Pyrometers are able to measure a temperature directly as a function of an object's electromagnetic radiation. The methods by which this is acheived can become rather complex, but in their simplest form all pyrometers consist of a lense to concentrate radiation into a point or array of points and an absorber, which chemically translates radiation into terms of flux. It is at this point that the line between sensing and transducing becomes blurred for me. David gives a good explanation of these principles as applied to an array of infrared sensors (thermography).  By some means of transduction the radiation is translated to thermal energy and the thermal energy is translated to an electrical current. The figure below helps explain the process.

References:
http://drexel.summon.serialssolutions.com/search?s.q=thermal+radiation+sensor

http://site.ebrary.com/lib/drexel//docDetail.action?docID=10438390

http://www.electronics-tutorials.ws/io/io_3.html

http://en.wikipedia.org/wiki/Pyrometer

Temperature Sensors

There are many different types of temperature sensors, and many of them operate in completely different ways. The most basic type of temperature sensor is the classic mercury thermometer. This sensor works purely based on the expansion and contraction of mercury in a glass tube. The next step up technologically is the bimetallic strip temperature sensor. This sensor makes use of the different coefficients of expansion that different materials have. These sensors are usually composed of steel and copper, which expand and contract at different rates. This sensor takes the temperature change, and turns it into a mechanical displacement. This technique can be used in many different types of sensors.

There are also much newer sensors that instead of turning heat into mechanical energy, they read the heat change in a difference of electrical energy. The two most common sensors are a thermistor and a resistance thermal detector (RTD). These two objects work on very similar principles, they both measure the change in resistance and correlate it with the change in temperature. The main difference between the two is the materials used to make them. Thermistors use primarily ceramic, whereas RTDs use pure metals. This difference in materials usually results in thermistors having a more accurate reading in a smaller range of temperatures whereas RTD stay accurate even at extreme temperatures.

Most of the previous sensors all require contact, or to be within convection range of the heat source to get a viable reading, however there are also non-contact thermal sensors that use radiation. These sensors use Plank's Law to correlate the radiation given off by an object and its overall temperature. These sensors are really useful as you can measure the temperature of something while being far away from it, whether it be the temperature in an oven, or the temperature of the sun.

Of all these sensors, the most useful for our applications is the RTD. The sensors themselves are really just metal, so they have no moving parts, and never need to be calibrated. Because of the simplicity and cheapness of these sensors they can easily be applied almost anywhere in a building. Couple the readings of these sensors along with the HVAC system or even window/blinds control and, without any human interaction, a room could always be at an optimal temperature. This is just one example that these sensors could be used in, the fact that they are so small and cheap and easy means they could be used almost anywhere, in ovens, in fridges, in water heaters, anywhere that temperature levels are of interest, these types of sensors could be applied.

Because I was the first to post, I discussed the history of sensors and their many different types. It seems the other posters used mine as a base and talked about what the different sensors are used for now or what they could be used for in the future. David talks about thermography which, in simple terms, is seeing heat which I think is a really cool concept and, like David said, has many uses including assisting fire fighters to save lives. Nathan goes on to discuss how IR sensors are used a lot in cooking to ensure the quality of food. Not only is it being used to ensure the food is done cooking, but I just saw on the news the other day, police are pulling over food delivery trucks and using these IR sensors to ensure the truck is at correct temperature for food shipment.

Sources:
http://www.ehow.com/how-does_4928076_temperature-sensor-work.html
http://www.instructables.com/id/Temperature-Sensor-Tutorial/
http://en.wikipedia.org/wiki/Bimetallic_strip
http://en.wikipedia.org/wiki/Thermistor
http://en.wikipedia.org/wiki/Resistance_thermometer

es queue el

Nathan gives a pretty good overview of the function of SQL servers, and the degree of standardization that is common to the language. As he mentions, it is important to have a Structured Query Language to manage databases in an understandable way, allowing us to find and modify data once the database has been created. After some initial confusion pertaining to the jargon used to describe how SQL works, I found the actual functions it implements to be very intuitive. Each function's name describes what it does. For example, the all-important SELECT function allows programs to search and retrieve data from a specific database table, with further modifiers embedded within the function to refine the search (FROM, WHERE, etc.), and organize the output (ORDER BY, GROUP BY). I found Wikipedia's explanation of this function (and others) very helpful.

Figure 1 - SELECT function explanation

I like that David describes the databases themselves as "glorified excel sheets," especially since this definition is coming from someone with some experience with databases. From my rudimentary understanding of the topic, that is exactly how I pictured and SQL database, some enormous table made up of labeled columns with rows of data beneath. It makes sense that by this system, and particular piece of data can be pinpointed by some row and column designation, much like an X and Y coordinate in the cartesian system.

What intrigued me most about this week's topic was not necessarily how the system works, but how often it needs to work. I gather from the articles I read, that every single user-interfaced program uses some form of database and query system to make it run. For simplified applications this may be a flat-file-database, as David explains. However it is my impression that, for the large majority of complex applications, the SQL format is used. A recent article puts into perspective the importance of the ability to manipulate and query these formatted data.  As our sensing capability and aptitude for data recording grows, the challenges involved in organizing, maintaining, and using this data also grows. For example in the medical field there are virtual reams of unused data pertaining to patient records, and no unified system for managing all of this. As data becomes more and more digitized, it seems reasonable that we must decide how we want to organize this data so that it is easily accessible when we need it. The SQL is currently the ANSI specified way to do that, and while it is not without complications, the basic structure of database and query language remains the same across the board.

Finally, one of the biggest issues in current SQL design is the timing of the SQL servers. Database size has grown significantly since the SQL language was invented, and as a result we are having to deal with time lag as SQL applications search through these seas of information for specific data. ANSI is still updating specifications, with its latest release in 2012, to account for the evolving nature of database organization and navigation.

References:

"Database Management: Big Data will soon be the norm" - Sunday Business Post

SQL For Dummies - 7th Edition

Structured Query Language

As everyone else has been saying, SQL (Structured Query Language) is a computer language that specifically manages databases.  It happens to be one of the first commercial languages developed by IBM in 1970.  In 1986 SQL became a part of the American National Standard Institution (ANSI) and the International Organization for Standards (ISO).  This is to help keep the SQL up to date as with all of the other technology.  There are still some issues, however, with SQL code.  This is due to the standards not being followed as strictly as they should.  This goes along the lines of what John said about interoperability.  The standards are there so that SQL will always remain interoperable.  However, if they aren’t followed as specified, that is when there become problems. 

SQL has 6 major language elements, also brought up by John, which are clauses, expressions, predicates, queries, statements, and insignificant whitespaces.  The use of these elements can be seen in the following figure. 

Note that insignificant whitespaces are “insignificant.”  SQL ignores spaces and therefore they can be used to make the language readable. 

SQL language is used for two major reasons updating data and retrieving data from a database.  Most databases use SQL, however, often times they have their own extensions that will only be used on that specific system.  Although SQL is the only thing needed to do the basic maneuvering of a database, which are: Select, Insert, Update, Delete, Create, and Drop.  For anybody interested in getting a tutorial in SQL they should visit the website SQLCourse.com and it goes through the steps in making a simple database using SQL. 

As David pointed out, SQL is a great resource to have and is much more efficient than using a flat file database.  I like his example about Facebook and filtering all of the information down to what pertains to you.  This put everything into perspective for me.  Reading the Wikipedia page on SQL and other sources I was not following.  Only when I read this example did I understand the function of SQL, which made the other literature easier to comprehend. 

Sources:

http://en.wikipedia.org/wiki/SQL

http://www.sqlcourse.com/index.html