# Question 4: Estimating Concrete Strength

Engineering and Construction Assignment-Write my Custom Paper

You work for a construction firm who need to be able to accurately predict the compressive strength of concrete given variables including the concrete composition and its age. You are aware that the relationship between these different components and the concrete strength is complex, however you have been asked to investigate how well a simple linear model works for prediction. Using the provided data (Concrete_Data.xls), develop models to predict:

• Concrete strength from the single best indicator variable;
• Concrete strength from all variables.

With the second model, determine if any variables are not contributing significantly to the model, and what impact removing these has on prediction performance. Comment on the final model and its accuracy.

(Provide any code or visualisations you use to justify your response.)

# Question 3: Ethanol engine emission testing

Your engine testing company has been evaluating the relationship between engine capacity (in cubic cm) and particulate emissions (in particles per milliliter) across a range of engines. Now you have received results from tests of 100 ethanol-fuelled engines and your supervisor has sent you the following email about that:

Hi there. Just wanted to say I’ve done a quick analysis of the 100 ethanol engine emissions in Matlab and got the following:

Look’s like the higher the capacity, the more emissions we get from the ethanol engines… Weird huh? When we looked at diesel and petrol engines, emissions went down!? Can you check the data for me?

Take a look at the emissions data for the 100 ethanol engines in the file “Engines.csv” and write an email to your supervisor explaining your findings.
(Provide any code or visualisations you use to justify your response.)

# Question 5: Predicting Missing Bikeway Data

Brisbane City Council (BCC) is considering upgrades to the bikeway networks. They are using data they have gathered from sensors placed along the bike paths, which record the number of cyclists, to plan the upgrades, however there have been a number of sensor failures which have resulted in their dataset missing a number of entries. BCC have requested that you investigate if it possible to predict missing data from data gathered from other sensors on the bike path network.

You have been provided with three years worth of data (Bike-Ped-Auto-Counts-2014.csv, Bike-Ped-Auto-Counts-2015.csv, and Bike-Ped-Auto-Counts-2016.csv). As an initial investigation, you have been asked to consider only these data series:

• BicentennialBikewayCyclistsInbound
• GoBetweenBridgeCyclistsInbound
• KangarooPointBikewayCyclistsInbound
• NormanParkCyclistsInbound
• RiverwalkCyclistsInbound
• StoryBridgeWestCyclistsInbound

Using the three years data, you are to:

• Determine which counters are best suited to predicting the missing data in others.
• Predict missing data where appropriate.
• Comment on the resulting corrected dataset. What problems, if any, may arise from this approach? How effective has this been in reducing missing data?

(Provide any code or visualisations you use to justify your response.)

# Question 2: Changes in Air Quality Over Time

The state government’s Department of the Environment and Heritage Protection are concerned about air pollution levels in Brisbane city. You have been provided with data for two sites, the Brisbane CBD and South Brisbane, for 2010 and 2016 in the following four files:

• brisbanecbd-aq-2010.csv
• brisbanecbd-aq-2016.csv
• southbrisbane-aq-2010.csv
• southbrisbane-aq-2016csv

You have been asked to advise the Government:

• If air pollution is related across the two sites, and if so, has this relationship changed between 2010 and 2016
• Has the level of air pollution at either site changed from 2010 to 2016? Have these changes across the two sites been consistent?

You have been advised to focus on the PM10 data series.

(Provide any code or visualisations you use to justify your response.)

# Question 1: Recommending a bolt supplier

Your firm works in construction and buys ASTM A325M8S bolts in very large numbers.

You are interested in purchasing bolts from different suppliers and have obtained and tested samples of 200 bolts from three suppliers: Allnutt, Boltzman, Coachers.

You have tested these in your new bolt testing machine, purchased after you had discovered your old bolt testing machine was performing erratically. (For the purposes of this question, you are safe to assume that the new machine works perfectly and that its results are in MPa.)

Your firm wants to ensure that the tensile strengths of the bolts it buys are

• as high as possible
• as consistent as possible (i.e., the variability of bolt strengths is as low as possible)

It is critical that the tensile strength of these bolts exceeds 830MPa.

On the basis of the measurements recorded in Bolts.csv, which supplier (if any) would you recommend, and why?
(Provide any code or visualisations you use to justify your response.)