Industrial Engineering - Course code 4024

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Explain how the Operating Characteristic (OC) curve helps in evaluating the effectiveness of an acceptance sampling plan. Be specific about what aspects of the plan it reveals.

The OC curve visually represents the probability of accepting a lot with a certain defect level. It reveals the discriminating power of the sampling plan, showing the producer's and consumer's risks associated with different quality levels.

A project estimate contains various elements. What are the principal constituents a project estimator must consider to develop and refine the initial estimate, and why is each important?

Principal constituents include direct costs (labor, materials), indirect costs (overheads), and contingency reserves (for unforeseen risks). These are crucial for accurate budgeting, resource allocation, and risk mitigation, ensuring project financial viability.

A company produces widgets with a direct material cost of $5, direct labor cost of $3, and factory overhead of $2 per widget. If the company wants to achieve a 20% profit margin on the total cost, what should the selling price per widget be?

Total cost per widget is $5 (material) + $3 (labor) + $2 (overhead) = $10. To achieve a 20% profit margin, the selling price should be $10 + (0.20 * $10) = $12.

Compare and contrast Estimating and Costing based on their objectives.

Estimating aims to forecast costs before a project begins to aid in decision-making and budgeting. Costing, on the other hand, determines the actual costs incurred during and after the project to performance and profitability. Signup and view all the answers

A machine is purchased for $10,000 with an estimated salvage value of $1,000 after 5 years. Calculate the depreciation expense for the first year using both the straight-line method and the double-declining balance method. Show your work.

Straight-line depreciation: ($10,000 - $1,000) / 5 = $1,800. Double-declining balance: (2 / 5) * $10,000 = $4,000. Signup and view all the answers

Explain how a U-shaped assembly line can improve efficiency compared to a traditional straight-line layout, considering factors like material handling and operator movement.

A U-shaped line reduces material handling distances and promotes better communication and visibility between workers, leading to improved efficiency and reduced bottlenecks. Signup and view all the answers

Describe the steps involved in conducting a method study for optimizing a specific workstation task. Focus on the stages where the most significant improvements are typically identified.

Select, Record, Examine, Develop, Install, Maintain. Significant improvements often occur during Examination (critical analysis) and Develop (creating improved method) stages. Signup and view all the answers

A manufacturing company is considering two locations for a new plant. Location A has lower labor costs but higher transportation costs. Location B has higher labor costs but lower transportation costs. What approach can be used to decide which one is optimal?

Cost analysis should be done calculating total cost of each location considering all the factors such as labor cost including all benefits, transportation costs, raw material cost, rent/establishment cost, tax benefits, and etc. The location with the lower total cost will be the optimal one. Signup and view all the answers

Explain how the Economic Order Quantity (EOQ) model helps in optimizing inventory costs. What assumptions must hold true for the EOQ model to be valid?

EOQ minimizes total inventory costs by balancing ordering and carrying costs. Key assumptions include constant demand rate, fixed ordering cost, and no stockouts. Signup and view all the answers

Differentiate between 'preventive maintenance' and 'breakdown maintenance.' Provide an advantage and disadvantage of each approach.

Preventive maintenance is scheduled maintenance to prevent failures while breakdown maintenance is repairs done after a failure. Preventive maintenance advantage: reduces unexpected downtime. Disadvantage: higher upfront costs. Breakdown maintenance advantage: lower initial costs. Disadvantage: potential for production delays. Signup and view all the answers

Describe the purpose of a control chart in statistical quality control (SQC). How do control limits help in identifying potential quality problems?

Control charts monitor process variation over time. Control limits define the acceptable range of variation; points outside these limits indicate a process is out of control and requires investigation. Signup and view all the answers

Explain the concept of 'acceptance sampling' in quality control. Why might a company choose to use acceptance sampling instead of 100% inspection?

Acceptance sampling is inspecting a subset of a batch to decide whether to accept or reject the entire batch. It's used instead of 100% inspection due to cost, time constraints, or destructive testing. Signup and view all the answers

A company purchases a machine for $50,000. It has an estimated useful life of 10 years and a salvage value of $5,000. Using the straight-line depreciation method, calculate the annual depreciation expense.

The annual depreciation expense is $4,500. (($50,000 - $5,000) / 10 = $4,500) Signup and view all the answers

How does the 'bathtub curve' illustrate the failure rate of equipment over its lifespan, and how can this information be used to optimize maintenance strategies?

The bathtub curve shows high failure rates early and late in equipment life, with a lower constant failure rate in between. This informs maintenance by suggesting early preventive actions, condition-based maintenance during stable periods, and predictive maintenance as equipment ages. Signup and view all the answers

Compare and contrast 'Preventive Maintenance' with 'Predictive Maintenance'. How do cost, data requirements, and potential for preventing failures differ between these two approaches?

Preventive maintenance is schedule-based, lower cost initially, and has fewer data requirements. Predictive maintenance uses condition monitoring for targeted interventions, higher data requirements, and offers better failure prevention by addressing issues early. Signup and view all the answers

Explain how implementing a Combination Layout can benefit a manufacturing plant that produces a variety of products with differing production volumes.

A Combination Layout blends process and product layouts. It's beneficial because it allows for efficient high-volume production using product layout principles while accommodating the flexibility needed for diverse, lower-volume products through process layout areas. Signup and view all the answers

Describe the key differences in the routing and scheduling processes between Mass Production and Job Order Production systems.

In Mass Production, routing and scheduling are standardized and repetitive due to consistent product flow. Job Order Production requires flexible routing and dynamic scheduling to accommodate unique job requirements and varying process sequences. Signup and view all the answers

Explain the trade-offs a company must consider when deciding between investing in Automated Guided Vehicles (AGVs) versus forklift trucks for material handling.

AGVs offer automation, reduced labor costs, and improved safety but have high initial investment and require structured environments. Forklifts are more flexible and cheaper upfront but have higher labor costs and potential for accidents. Signup and view all the answers

How can Gantt charts be utilized to improve scheduling efficiency in a batch production system?

Gantt charts help visualize project timelines, task durations, and resource allocation. In batch production, they allow for efficient sequencing of batches, identification of bottlenecks, and monitoring progress against schedule, enabling better resource utilization and timely completion. Signup and view all the answers

Explain how forecasting accuracy impacts the effectiveness of Production Planning and Control (PPC) functions such as routing and scheduling.

Inaccurate forecasts lead to mismatches between planned production and actual demand, causing inefficient routing, under/over utilization of resources in scheduling, increased inventory costs, and potential delays. Accurate forecasts enable better optimized PPC. Signup and view all the answers

Discuss how the principles of material handling can be applied to reduce bottlenecks and improve workflow in a manufacturing facility.

Applying material handling principles like minimizing travel distances, using gravity where possible and utilizing efficient equipment reduces bottlenecks by ensuring smooth material flow, decreasing work-in-progress, and optimizing space utilization, leading to streamlined workflows. Signup and view all the answers

Explain how a flow process chart can be utilized to optimize the layout of a manufacturing facility.

A flow process chart visually represents the sequence of steps in a process, allowing analysts to identify bottlenecks, redundancies, and unnecessary movements. By analyzing the chart, improvements to the layout can be made to minimize material handling, reduce travel distances, and streamline the overall flow of production. Signup and view all the answers

Differentiate between a flow diagram and a string diagram in method study and give an example where a string diagram would be more appropriate.

A flow diagram is a graphical representation of the sequence of steps in a process, while a string diagram is a scaled plan that uses a string to trace and measure the actual path taken by a worker or material. A string diagram would be more appropriate when analyzing the movements of a security guard patrolling a large area to optimize their route. Signup and view all the answers

Describe how employee rating factors are utilized to adjust observed times during a time study and why this adjustment is necessary.

Employee rating factors are used to normalize the observed time of a worker to the time a qualified worker would take performing at a standard pace. This adjustment is necessary because a worker's performance during the time study may not reflect the standard pace, and standard time needs to represent a typical, sustainable working speed. Signup and view all the answers

A worker takes 15 minutes to complete a task. During the time study, the analyst rates the worker's performance at 110%. If the allowance for a task is 10%, calculate the standard time for the task.

Standard time = (Observed time * Performance rating) + Allowance. In this case, (15 minutes * 1.10) + (15 * 1.10) * 0.10 = 16.5 + 1.65 = 18.15 minutes. Signup and view all the answers

Explain the difference between first piece inspection and floor inspection in a quality control process. Why are both important?

First piece inspection is the examination of the initial item produced in a production run to ensure it meets specifications, while floor inspection involves ongoing checks at the workstation during production. Both are important; first piece inspection prevents a large batch of defects, and floor inspection ensures consistent quality throughout the production process. Signup and view all the answers

Describe a scenario where using a p-chart would be more appropriate than using an x-bar chart in statistical quality control. Explain why.

A p-chart, which monitors the proportion of defective units in a sample, would be more appropriate than an x-bar chart when inspecting the number of late deliveries per week out of total deliveries made. An x-bar chart is used to track continuous variables, but a p-chart is suitable for tracking the proportion of nonconforming items. Signup and view all the answers

A manufacturing process has a mean of 50 and a standard deviation of 2. If a single item is randomly selected from this process, what is the probability that the item will be between 48 and 54? (Assume a normal distribution.)

To calculate the probability, you need to find the z-scores for 48 and 54. $z_1 = (48 - 50)/2 = -1$ and $z_2 = (54 - 50)/2 = 2$. Look up these z-scores in a standard normal distribution table or use a calculator. The probability is approximately 81.85%. Signup and view all the answers

Differentiate between 'rest allowance' and 'special allowance' in the context of work measurement and provide an example for each.

Rest allowance is time provided to recover from fatigue and personal needs, like a short break every two hours. Special allowance covers irregular but expected delays or tasks not part of the standard job cycle, like machine setup after a breakdown. Signup and view all the answers

Flashcards

Industrial Engineer Role

Oversees production from planning to costing, enhancing efficiency and productivity.

Plant Layout

Systematic design and arrangement of equipment, machinery, and departments to optimize workflow.