Past Exam Questions that I got wrong Flashcards
If Activity B, C and D are on the same activity path, and all activities have two days of total float, when Activity B consumed two-day total float, how many days of total float do Activity C and D have?
Idk
Describe the difference between Monte Carlo and Latin Hypercube sampling.
- In random sampling (Monte Carlo) new sample points are generated without taking into account the previously generated sample points. One does not necessarily need to know beforehand how many sample points are needed.
- In Latin Hypercube sampling one must first decide how many sample points to use and for each sample point remember in which row and column the sample point was taken.
Describe the Hawthorne Effect.
- Organisations not just formal structures but social networks
- People will act differently when they know they are being observed
- Quality of the supervision has an impact on the quality & quantity of the work output
Describe the Allais Paradox in bullet points.
- Most decision makers do not choose the action with maximum expected utility / ‘rational’ approach (take account of probability & consequence of possible outcomes).
- Instead, people make decisions seemingly ‘irrational’ decisions.
- However, these are not irrational and are actually just a result of the way people value the possible outcomes - this is the subject of utility theory!
What are the differences between then Net Present Value method and the Payback Method?
NPV:
- Accept all projects with a positive NPV.
- NPV = Present value of cash flows minus initial investments.
Payback:
- Accepts all projects that have a payback period less than a specified cut-off period.
- Payback period = Time until cash flows recover the initial investment of the project.
Describe the Scientific Management Method and bullet point its disadvantages.
4 principles:
1. Use scientifically optimised work routines
2. Scientifically select and train workers (good in, bad out)
3. Ensure work routines are followed (optimal way)
4. Managers and workers to use scientific methods
This looks like:
- Micromanagement
- Division of labour (everyone did one thing each - production line)
- Separate managers from workers
- Employees only follow direction
- Select and train high performing employees and match them to the right job
- More productive workers should be paid more, fire those who could not meet expectations
Disadvantages:
- Monotomous work. Dehumanising
- Low job satisfaction
- Worker is measured by output alone
- If productivity of workers goes up but market requires no increased output?
- Payment concerns.
What are disadvantages of FTA and ETA?
- Only examines one top event / initiating event.
- In complex cases, with many events/branches/gates, not efficient.
- Difficult to capture time-related, human error, adverse weather etc. due to binary logic.
What are disadvantages of MCA?
- Weighting factors are often difficult to agree on by many parties.
- There may be inconsistencies within weighting factors.
What are disadvantages of AHP?
- If measures are not relevant the AHP process is meaningless.
- Consistency Ratio tells us if our matrix is consistent, however, humans are naturally inconsistent, therefore many iterations could be necessary if we want a consistent rational result.
- As the number of pairwise comparisons increase drastically with the increase of n.
- With a large number of comparisons humans do not tend to value each pairwise comparison equally. As participants go down the list participants get lazy. This can hugely influence your decision {w}.
- Dependent variables can be a problem.
In bullet points discuss the differences between Traditional and Lean construction methods.
Traditional | LEAN
- Decisions are made sequentially by specialists and ‘thrown over the wall’ | Downstream players are involved in upstream decisions, and vice-versa
- Activities are performed as soon as possible | Activities are performed at the last responsible moment
- Not all product life cycle stages are considered in design | All product life cycle stages are considered in design
- Participants build up large inventories to protect their own interests | Buffers are sized and located to perform their function of absorbing system variability
- Organizations link together through the market, and take what the market offers | Systematic efforts are made to optimize supply chains
- Learning occurs sporadically | Learning is incorporated into project, firm, and supply chain management
Explain the difference between top-down and bottom-up estimates.
Top-down (Parametric) estimating:
- Divide a project into units of work. Then, you must determine the cost per unit, and then multiply the number of units by the cost per unit to estimate the total cost.
- Preliminary design estimate
- Allows selection of the best of identified project approaches, analyse concept(s) and prepare Cost Estimate to confirm project viability
Bottom-up (First Principles) estimating:
- Building-up prices, or rates, for an item or piece of work considering all the parts and activities needed to put it together.
- Detailed design estimate
Describe Blanchard’s Situational Leadership Theory. Draw a diagram and explain each part of the diagram.
Diagram:
- y - Directive Behaviour, x - Supportive Behaviour
- Top left - Directing (Beginner) –> Top right - Coaching (Learner) –> Bottom right - Supporting (Contributor) –> Bottom left - Delegating (Achiever).
- Directing: Leaders define roles and tasks of the ‘follower’ and supervise them closely. Decisions are made by the leader and announced, so communication is largely oneway. Beginners: When first beginning a new task where they have had little, if any, prior knowledge or experience, most individuals are enthusiastic and ready to learn - but at a low competence level for the task.
- Coaching: Leaders still define roles and tasks, but seeks ideas and suggestions from the follower. Decisions remain the leader’s prerogative, but communication is much more two-way. Learners: As the development level of an employee increases, his or her competence and commitment fluctuate. Need Coaching, high direction to continue to build skills as well as high support to address their low commitment.
- Supporting: Leaders pass day-to-day decisions, such as task allocation and processes, to the follower. The leader facilitates and takes part in decisions, but control is with the follower. Contributor: As competence continues to improve, most individuals go through a self-doubt state where they question whether they can perform the task on their own. Need to be listened to and encouraged but do not need much direction, since they have demonstrated that they have the competence to do the task.
- Delegating: Leaders are still involved in decisions and problem-solving, but control is with the follower. The follower decides when and how the leader will be involved. Achiever: Finally, at the highest level of development, employees demonstrate high levels of competence and commitment.
Heavy equipment machines are usually rated by their:
Heaped Capacity (H)
How do you know if a transition matrix [P] is regular?
What does it mean?
Some power of [P] has only positive values.
The Markov chain has a unique stationary matrix AND successive matrices always approach the stationary matrix.
What 5 basic factors are important when assessing equipment productivity?
E = Efficiency hours (min/hr)
I = In-bank correction factor (load factor)
H = Heaped capacity of machine (m^3)
B = Capacity adjustment facotr (bucket fill factor)
C = Cycle time of machine (min)
