APICS_ECO 经典350题库

1-1Backlogs should be held:

A) On the shop floor

B) At the customer

C) In production control

D) In the warehouse

The correct answer is C)

By keeping the backlogs in production control, the floor will

not be overloaded with work which cannot be completed,

thereby rendering due dates invalid on the floor. When the

shop is overloaded, product gets moved more frequently

and changeovers become more frequent, reducing the

available capacity.

1-2The time period which exists between the completion

of one operation and the start of the next operation is:

A) Wait time

B) Set-up time

C) Interoperation time

D) Pre-operation time

The correct answer is C)

Interoperation time includes move time, queue time, and

wait time.

1-3Which of the following is associated with backward

scheduling?

A) Finite loading

B) Infinite loading

C) Interoperation sequencing

D) Dispatch lists

The correct answer is B)

With infinite loading, the load on the plant is determined by

the customer due date scheduled backward without regard

to standard capacity available to perform the work.

Capacity is then reviewed for potential improvements

through overtime, subcontracting, etc.

1-4Given the following information for a work center:

Machines = 3

Operations per shift = 2

Shifts per day = 1

Days worked per week = 5

Hours worked per shift = 8

Machine utilization = 80%

Operator efficiency = 90%

If the hours worked were increased to a 10 hour shift

from an 8 hour shift, what would the available capacity

be for the week?

A) 100

B) 108

C) 120

D) 150

The correct answer is B)

Available weekly capacity would be 3 machines x 50 hours

per week x .80 machine utilization x .90 operator efficiency

= 108.

2-1Which of the following is affected when input does not

match output?

I. Lot sizes

II. Lead times

III. Queue sizes

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is C)

If input is greater than output, queues and lead-times will

increase; if output is greater than input, they will decrease.

2-2The JIT philosophy calls for reducing lot sizes. Which

of the following would represent a good way to cut lot

sizes?

A) Reduce the lot size to one and identify the

problems

B) Cut the lot size in half and solve the problems that

surface

C) Cut the lot size in half but be sure inventory is on

hand in case the problems can't be resolved

D) Cut the lot size to equal one week's production

The correct answer is B)

By cutting the lot sizes in half, some problems will surface

to solve; however, there won't be so many that you

cannot deal with them. When the problems created by

the first lot size reduction are resolved, cut the lot sizes

again for more problems to surface. This is the "one less

at a time" process of gradually reducing lot sizes.

2-3Which of the following best describes the results of total

quality control?

A) Statistical tests of production identify sources of

defects.

B) The number of inspection stations is decreased in the

production process.

C) The product is made right the first time.

D) The cost of scrap and rework is below budget.

The correct answer is C)

2-4An operator falls behind the flow and a small bottleneck

occurs at a workstation. The operator switches on the

signal light, and the two operators at the adjacent

workstation immediately move in to help. Soon, the

bottleneck is relieved, and the two return to their

workstations. The procedure described above includes

examples of all of the following EXCEPT

A) Leveling. B) Teamwork.

C) Visibility. D) Flexibility.

The correct answer is A)

2-5The main objective of line balancing in an assembly

operation is to

A) Provide maximum mobility of operators between

assembly lines.

B) Minimize the total number of parts required for each

assembly line.

C) Develop work standards for cost-estimating purposes.

D) Distribute the work to maximize line output.

The correct answer is D)

3-1Which of the following will be reduced through small lot

manufacturing?

I. Work-in-process inventory

II. Defective parts produced

III. Machine operator skills

A) I and II

B) I and III

C) II and III

D) I, II, and III

The correct answer is A)

Small lot manufacturing will reduce work-in-process

inventory and increase quality so the number of defective

parts produced is lower. In order to do this, operator skills

will have to increase to include functions such as problem

solving and Statistical Process Control.

3-2Often, dissimilar machines will be grouped into U

shaped cells. The benefit(s) from organizing the

manufacturing in this manner is/are:

I. Leadtimes are shortened

II. Floor space taken is much less

III. Machine downtime is reduced

IV. Work-in-process inventory is lower

A) I, II, and IV B) I, III, and IV

C) II, III, and IV D) I, II, III, and IV

The correct answer is A)

The reasons for creating a U shaped cell are many.

Because the space required is less, the leadtimes are

shortened and there are no queues formed inside the cell.

Additionally, this reduction in queue and the lack of

inventory inside the cell also causes the inventory to

decrease. Unfortunately, machines can still break down

unexpectedly, even if a good preventive maintenance

program is in place.

3-3In order to monitor the capacity requirements plan,

which of the following techniques would be used?

A) Finite loading

B) Rough-cut capacity control

C) Input/Output control

D) Critical ratio

The correct answer is C)

Input/output control ensures that only work which can be

completed is planned for the given work center. The

output is compared to the input so planned output equals

or exceeds planned input. Actual results are measured

against the plan.

3-4------------------------------------------------

WORK CENTER 210 (in standard hours)

------------------------------------------------

1 2 3 4 5

PLANNED INPUT 150 150 150 150 150

ACTUAL INPUT .150 145 130

CUMULATIVE 0 -5 -25

DEVIATION

------------------------------------------------

PLANNED OUTPUT 180 180 180 180 150

ACTUAL OUTPUT .185 140 160

CUMULATIVE +5 -35 -55

DEVIATION

------------------------------------------------

Based on the input/output control chart above, backlog

is planned to be reduced by:

A) 90 hours

B) 120 hours

C) 150 hours

D) No reduction

The correct answer is B)

Output was planned to be 30 hours higher than input for 4

weeks for a total of 120 hours.

4-1Which of the following best describes the technique,

"Critical Ratio"?

A) It helps plan capacity

B) It helps with priority planning

C) It determines when to change the MPS

D) None of the above

The correct answer is B)

It helps determine priorities by finding the ratio between

time remaining and work remaining. If the ratio is less

than 1.0, it indicates being behind; if the ratio is greater

than 1.0, it indicates being ahead of schedule.

4-2Department A produces part XYZ in 4 operations.

During the prior month, the department earned 1200

standard hours by producing 1000 parts. The

department worked 1000 hours to produce these parts.

What is the department efficiency?

A) 83%

B) 100%

C) 120%

D) 200%

The correct answer is C)

Efficiency is determined by dividing the standard hours

earned by the actual hours worked or: 1200/1000 = 1.20

or 120%.

4-3In the XYZ widget company, every piece of a given lot

must be finished before any piece of the lot is

processed at the following work center. This company

is running:

A) A gapped schedule

B) A finite schedule

C) A detailed operation schedule

D) An infinite schedule

The correct answer is A)

A gapped schedule is run when every piece in a lot is

finished before being processed into the next operation.

This causes gaps in time between the end of one

operation and the beginning of the next operation.

4-4Inventory shrinkage has occurred when physical inventory

dollars are less than book inventory dollars. What

is the effect of inventory shrinkage on a company's profit

and loss statement?

A) Decrease in the cost of goods manufactured.

B) Increase in inventory dollars.

C) Decrease in sales dollars.

D) Decrease in profits.

The correct answer is D)

4-5Network analysis (PERT/CPM) is a scheduling technique

used primarily in

A) Job shops where many alternate routings are possible.

B) Continuous process companies using flow control.

C) Companies working on projects that have fairly

well-defined beginnings and endings.

D) Companies using computer-aided manufacturing (CAM)

applications.

The correct answer is C)

5-1The process of spreading orders or rescheduling

operations so the work is distributed evenly is known

as:

A) Operations scheduling

B) Infinite loading

C) Load leveling

D) Backward scheduling

The correct answer is C)

Load leveling involves spreading orders or re-scheduling

operations so the work is distributed evenly and can be

achieved. This ensures the factory is not overloaded for

two weeks and idle the next two, for example.

5-2In a sequence of operations without alternate routings,

capacity and the whole sequence of operations can be

scheduled by the operation with the least capacity.

This operation is known as:

A) The gateway operation

B) The limiting operation

C) The downstream operation

D) The sequencing operation

The correct answer is B)

The limiting operation, also known as the bottle-neck

operation, can be used to schedule the whole sequence of

operations since work can only proceed as fast as the

slowest point.

5-3In a job shop environment, which of the following are

true?

I. Less work in process inventory increases lead times

II. Longer queues increase lead times

III. More work-in-process means increased lead times

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is C)

The more work held on the production floor, the longer the

lead-time will be. This happens because jobs begin to get

moved to meet customer demands. The result is that parts

get moved and shuffled, reducing capacity.

5-4Which of the following will be true if the cumulative

lead-time of a product is longer than the MPS planning

horizon?

A) Orders for long lead-time components will be

released late

B) Orders for long lead-time components will be

released early

C) Order point can be used for the longest lead time

items without affecting priorities

D) There is no impact

The correct answer is A)

The orders for the long lead-time components will be

released late as visibility will not be far enough into the

future.

5-5In a job shop environment, which of the following

elements of lead-time is generally the greatest?

A) Queue time

B) Run-time

C) Set-up time

D) Move time

The correct answer is A)

Queue time is the time a job waits at a work center

before work on set-ups are performed on the job. By

reducing queue time, manufacturing lead-time can be

shortened. This is quite often the longest portion of the

leadtime in a factory.

6-1The plant manager is responsible for:

I. Manufacturing to meet a schedule

II. Changing the schedule

III. Ensuring raw materials arrive in time

A) I

B) I and III

C) I and II

D) II and III

The correct answer is A)

The plant manager is responsible for ensuring products are

produced to meet the schedule in the priority assigned with

the best quality possible at the least cost possible.

6-2A job status report would show:

A) Costs accumulated for the job

B) The input and output of every work center

C) The plan for completing a job and the progress

versus the plan

D) The job priority at each work center

The correct answer is C)

A job status report shows the actual progress of a job

versus the completion date.

6-3An effective technique in a JIT environment to increase

management and staff involvement in the production

process is

A) Excepting reporting

B) Viewing operations through hidden TV cameras

C) Routine briefings by direct labor employee

D) Frequent plant walk-throughs

The correct answer is D)

6-4A primary role of a quality-assurance department in a

JIT environment is

A) Inspection of incoming goods

B) Sorting our defects on the assembly line

C) Training operators on process quality techniques

D) Cleaning and lubricating equipment

The correct answer is C)

6-5A major requirement for "making a little of each

product each day" is

A) No options are allowed

B) The use of cards or other signaling devices

C) Level customer demands

D) Quick set up and changeover

The correct answer is D)

7-1If a work center is becoming a bottleneck and

throughput time is getting longer, which of the following

could be a solution?

I. Decrease the input

II. Increase the planned lead times

III. Increase the capacity

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is B)

Essentially, the only way to relieve the bottle-neck is to

increase the output from the work center or decrease the

input. Increasing planned leadtimes will cause more work

to be released to the floor.

7-2Which of the following statements are true regarding

queues?

I. Queue size and lead time are interchangeable

II. Queue size and lead time are interconnected

III. Queue time is variable based on priority

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is C)

Queue size and lead time are interconnected since an

increase in queue size will increase lead time. However, if

a jo

b is a high priority by management, the queue size

won't matter.

7-3Which of the following best describes the term alternate

routing?

A) A routing similar to the primary routing which

produces an identical item of lesser quality

B) A routing less preferred to the primary routing which

produces an identical item

C) A routing which takes longer than the primary

routing and produces a similar, but not identical part

D) A routing for the supplier which exists on the

customers file

The correct answer is B)

An alternate routing is not preferred over the primary

because the machinery could be older, more variable, or

may take longer. However, the identical part is produced

within the quality specification.

7-4Given the following information on a work center:

Machines = 3

Operations per shift = 2

Shifts per day = l

Days worked per week = 5

Hours worked per shift = 8

Machine utilization = 80%

Operator efficiency = 90%

If the weekly load on the work center is 90 hours, the

work center is:

A) Overloaded

B) Underloaded

C) In balance

D) Not enough data

The correct answer is A)

The work center is overloaded because the standard

capacity is 3 machines x 40 hours per week x .80

machine utilization x .90 operator efficiency = 86 standard

hours.

8-1A replacement for a normal step in the manufacturing

process is:

A) Alternate routing

B) Smoothing

C) Alternate operation

D) Sequence

The correct answer is C)

An alternate operation would be used if the normal

operation was not running, so work could be completed.

8-2If more input is arriving at a work center than output

leaving the work center, which of the following will

occur?

I. Backlogs will grow

II. Lead-times will be longer

III. Work-in-process inventory will be higher

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

All of the answers will occur if more is input to the factory

or work center than can be expected out.

8-3When a set-up procedure occurs while a machine is

running, it is called:

A) Internal set-up time

B) Interoperation time

C) External set-up time

D) Gapped time

The correct answer is C)

External set-up time occurs when a set-up is completed

while the machine is operating. Internal set-up time

occurs when the machine is down.

8-4Based on the following information, calculate the

machine utilization for a 5-day week based on 8 hour

shifts (times are expressed in hours).

Day 1 Day 2 Day 3 Day 4 Day 5

Set up time 1.0 1.0 1.5 1.0 1.5

Run time . 6.0 5.5 5.5 6.0 5.5

Wait time 1.0 1.5 1.0 1.0 1.0

A) 71.25% B) 86.25%

C) 91.25% D) 97.50%

The correct answer is B)

Machine utilization is calculated by dividing direct time

charged to production activities by the clock time scheduled

for those production activities. In the question, 8 hours are

available each day or 40 hours for the week. Set up and

run time accounts for 34.5 hours or 86.25% (34.5/40.0).

8-5Which of the following are scheduled in manufacturing

lead time?

I. Time to purchase

II. Queue time

III. Run time

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is C)

Purchasing raw materials is not part of the manufacturing

lead time, but is part of the cumulative lead time.

9-1By increasing the capacity at the bottleneck work

center, which of the following will occur?

I. Manufacturing lead-times will be shortened

II. Work in process inventory will be reduced

III. Scrap will be reduced

A) I and II

B) I and III

C) II and III

D) I, II, and III

The correct answer is A)

By increasing the capacity at the bottleneck work center,

more work can "flow" out of the work in process. When

this happens, lead-times will decrease, as will work in

process. While scrap could be lower due to damage

caused by excess parts in the factory, it is not a direct

result.

9-2In which of the following businesses can shop floor

control procedures be best applied?

I. Make-to-stock

II. Make-to-order

III. Assemble-to-order

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

All types of manufacturing industries can receive benefits

from shop floor control procedures although each of them

have very specific issues.

9-3Effective shop floor controls can improve customer service

in which of the following ways?

I. By reducing production lead time

II. By replenishing stock orders on schedule

III. By improving parts availability

A) I only B) I and III only

C) II and III only D) I, II, and III

The correct answer is D)

9-4Which of the following are among the characteristics of

flow control scheduling?

I. Measuring movement past control points

II. Knowing capacities and planned rates

III. Matching work in process to specific customers

A) I and II only B) I and III only

C) II and III only D) I, II, and III

The correct answer is A)

9-5When allocated on the basis of historical direct labor

hours, overhead will be properly absorbed if which of

the following is true?

A) Total volume increases.

B) Total volume decreases.

C) Total volume remains unchanged.

D) Fixed costs decrease.

The correct answer is C)

10-1The most significant factor affecting the difference between

planned lead time and actual lead time for a specific

order or batch in a shop is

A) Priority

B) Capacity

C) Queues

D) Component availability

The correct answer is A)

10-2In Plant X, flow of purchased parts is from receipt at

dock to receiving/inspection to receipt at stores. In the

MRP system, inventory on hand is increased when

material is received at stores. Which of the following

statements are true about this situation?

I. A supplier delivery performance measurement should be

based on actual receipts at dock versus schedule.

II. Purchase orders should be closed when all parts are

received at stores.

III. A resource constraint could cause parts to be received at

the dock but not into the stores on schedule.

A) I and II only B) I and III only

C) II and III only D) I, II, and III

The correct answer is D)

10-3Employee involvement is the concept of using

A) Managerial employees to perform nonmanagerial tasks

whenever they are idle.

B) Employees to perform jobs outside of their assigned

duties without prior consent.

C) Employees' creative energy and intelligence in

certain decision-making processes.

D) All of the above.

The correct answer is C)

10-4Which of the following can be included as benefits of

cellular manufacturing?

I. Reduced order flow time

II. Lower setup time

III. Lower material handling costs

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

All of the answers can be included as benefits, in addition

to improved quality, less work-in-process, and improved

job satisfaction.

11-1In a just-in-time production environment, a ship-to-WIP

process is generally implemented as part of the JIT

project. Which of the following best describes the

ship-to-WIP process?

A) Daily deliveries of materials arrive at the dock

B) No shop orders are produced for production

C) Purchased materials are shipped to the point of use

without inspection

D) Material replenishment is driven by consumption

The correct answer is C)

In a ship-to-WIP process, purchased materials are shipped

directly to the point of use without being inspected. This

usually occurs when the vendor has been certified as a

quality vendor whose products will not need inspection.

11-2If a company implements a Just-in-Time project, which

of the following improvements will a customer most

likely receive?

A) Higher quality products

B) Lower freight costs

C) Smaller lot sizes

D) More deliberate design process

The correct answer is A)

Just-in-Time reduces the waste associated with producing

a product. As such, defects created during the manufacture

of a part would be eliminated through root cause analysis.

Freight costs might actually rise if frequent deliveries are

needed. Smaller lot sizes may not occur as a result of

implementing JIT. The design process may need to be

faster and less deliberate although waste in this process

could be eliminated.

11-3Which of the following would be found in a focused

factory?

A) Logical flows of materials through the factory

B) Plant layout by function

C) Increased paperwork to support the operation

D) Increased product variety

The correct answer is A)

A focused factory would generally run a smaller variety of

product down a logical flow in the factory. By focusing the

factory, product can flow down a production line in a

repetitive manner. By restricting the variety of parts being

produced, a flow can be achieved. A wider variety of parts

would make the line much more complicated.

11-4Which of the following physical characteristics are

important for parts containers in a JIT pull system?

I. Sized appropriately for the producing work center

II. Sized appropriately for the consuming work center

III. Designed so they can be moved by hand without

strain

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is C)

The parts containers contribute greatly to the success of

the pull system. They should be sized to feed the

consuming work center with the amount of work calculated

to be the lot size. They should also be designed to move

without material handling equipment.

11-5Suppliers for a manufacturer starting to implement JIT

may be hesitant, at first, to participate because:

A) Their prices may be reduced

B) Schedules may fluctuate without safety stock to

protect them

C) The inventory will be pushed back to them

D) Measurements will be more detailed

The correct answer is C)

Many companies, when they adopt the JIT philosophy,

begin by pushing the inventory back to the suppliers. This

only serves to move the inventory in the pipeline rather

than eliminate the inventory in the pipeline. This does

nothing to help either company because someone must

pay for the inventory which the supplier holds.

12-1Which of the following would best describe the term

poka-yoke?

A) Mistake proofing a process

B) Setups in less than 10 minutes

C) Lot size equal to one

D) Kanban sizing methodology

The correct answer is A)

The term poka-yoke refers to a technique of mistake

proofing a process. For example, having parts assembled

in a certain way so they can only be finished with all the

parts included. A set-up may be poka-yoked in such a

way so the fixture can only go in a certain way without

any manipulation.

12-2The goal of zero defects can be achieved by using

which of the following?

A) Well trained inspectors

B) Statistical sampling

C) Computerized ISO documentation

D) Poka-yoke work methods

The correct answer is D)

Only by mistake proofing the work methods can zero

defects be achieved. Well trained inspectors and statistical

sampling can only catch problems after they have occurred

and good documentation must be followed to be effective.

12-3The concept of deducting component inventory when

finished goods are received into stock is commonly

referred to as:

A) Floor deduction

B) Allocation

C) Material issues

D) Backflushing

The correct answer is D)

Backflushing occurs when the product is received into

finished goods inventory or at a count point in the

operation. The components are deducted from inventory for

the finished goods quantity times the bill of materials for

the product.

12-4Set up time reduction in a JIT implementation is very

important because:

I. Small lot sizes reduce inventory

II. Production output will increase

III. All of the products can be made constantly

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

Set up time reduction provides a great opportunity to

improve operations. Excess set up times use productive

capacity on the machine which could be used for

manufacturing parts, rather than being down for set up.

Reducing set up time also allows small lots to be

produced. The effect of these small lots is to produce only

the amount of product that is demanded by customers.

This reduces the amount of inventory being held.

12-5You are investigating the purchase of new machinery in

a lean manufacturing environment. Which of the

following would be the criteria for selecting the

equipment?

I. Flexible and low cost

II. Quick connect and disconnect capability

III. Single purpose machinery

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is A)

When purchasing machinery to support a lean

manufacturing environment, special attention should be

given to the flexibility of the equipment. The machines

should be easily adaptable to many parts and not just a

single purpose. This will provide flexibilty to the operation.

The machines also should support the quick changeover

needs of a lean manufacturing environment. Features such

as quick connect dies assist in speeding setup.

13-1Long term agreements with suppliers would provide for which of the following?

I. Paperwork elimination II. Cost reductions

III. Joint benefit projects

IV. Special trucking considerations

A) I, II, and III B) I, II, and IV C) II, III, and IV D) I, II, III, and IV

The correct answer is D)

Agreements with suppliers should be kept simple and should spell out the special arrangements of the partnership. Some of the considerations include the containers, trucking, cost reduction projects, and personnel contacts to ease communication. Supplier partnerships must be built on win/win relationships.

13-2

In order to analyze a material flow in a manufacturing process, which of the following tools will be most helpful?

A) Statistical process control chart

B) Fishbone diagram C) Process flow chart D) Force field analysis

The correct answer is C)

A process flow chart is used to analyze any flow of material, process, or information. It allows a person to view a picture of the given process. From this flow chart, action can be taken to improve the flow.

Questions 13-3, 4 refer to the following schedule of a two-operation job.

13-3

It can be concluded from Situation B on the schedule that A) Operation 10 is not a setup operation if operation 20 is a run operation.

B) Total job duration has been increased due to operation

overlap.

C) The percentage of operation overlap is different from that in situation D.

D) It is impossible to overlap operation 10 with operation 20.The correct answer is A)

13-4Based on the schedule, accurate conclusions include which of the following?

I. Increasing the number of shifts has greater impact on overall lead time than overlapping operations.

II. Increasing the number of shifts has less impact on

overall lead time than overlapping operations.

III. The combination of overlapping operations and increasing the number of shifts will result in the shortest overall lead time.

A) I only B) II only C) I and III only D) II and III only

The correct answer is C)

14-1Which of the following are reasons for purchasing outside

capacity?

I. It cuts down on training costs for new employees.

II. It permits increased output with no additional capital

investment.

III. It reduces overtime.

A) I and II only B) I and III only

C) II and III only D) I, II, and III

The correct answer is D)

14-2Which of these tools is most appropriate for contingency

planning?

A) Matrix chart.

B) Process decision program chart.

C) Pareto chart.

D) Continuous improvement chart.

The correct answer is B)

14-3As described in Just-in-Time, manufacturing activities

include which of the following ?

Ⅰ. Design

Ⅱ. Marketing and sales

Ⅲ. Production

Ⅳ. Finance

A) Ⅰ, Ⅲ

B) Ⅰ, Ⅱ, Ⅲ, Ⅳ

C) Ⅰ, Ⅱ, Ⅳ

D) Ⅱ, Ⅲ

The correct answer is B)

14-4There are three jobs to be completed on the schedule

with the following critical ratios associated with the jobs

as follows:

Job 123 0.75

Job 456 0.95

Job 789 1.10

Which job should be processed first?

A) Job 123 B) Job 456

C) Job 789

D) Not enough information to decide

The correct answer is A)

The job with the smallest critical ratio should be worked on

first as it is the furthest behind schedule. While some

extenuating circumstances may force you to run another

job first, the furthest behind would generally have priority.

14-5Which of the following elements of manufacturing

leadtime is generally the longest?

A) Move time

B) Setup time

C) Run time

D) Queue time

The correct answer is D)

Generally, only 10 to 20 percent of manufacturing leadtime

is actual operation time. The rest of the time is caused by

work in process time when the part is not being worked

on. Of this stagnant time, queue time accounts for the

longest time.

15-1A critical ratio of 0.75 means:

A) A job is ahead of schedule by 25%

B) A job is ahead of schedule by 75%

C) A job is behind schedule by 25%

D) A job is behind schedule by 75%

The correct answer is C)

Critical ratio is a measure of whether a job is on schedule

with the value of 1.00 being on schedule. To calculate the

critical ratio, the following formula is used:

Due date - today

--------------------------------

Lead time remaining to complete job

If the time remaining until the due date is less than the

lead time remaining to produce the part, then the job is

behind.

15-2Which of the following are requirements for a shop

order release?

I. Parts availability

II. Order due date

III. Tooling availabiltiy

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

Prior to releasing an order to the shop floor, components

must be available, the required due date should be known,

and the tooling must be available. If these rquirements are

not ready, then the order should not be released. Only

jobs which can be worked on should be released to the

floor.

15-3All of the following affect the queue time of a job at a

work center. However, which one of the following is the

most important factor affecting the queue time?

A) The existing queue time at the work center

B) The set up times on the various jobs

C) The lot size of the job

D) The priority of the job

The correct answer is D)

The priority of the job is the most important factor affecting

the queue time at a work center. The queue time will be

eliminated if the priority of the job is high enough to

bypass all the other jobs waiting for the work center (e.g.

President says to make the job next).

15-4Given the following information for a work center:

Machines = 2

Operations per shift = 3

Shifts per day = 1

Days worked per week = 4

Hours worked per shift = 10

Machine utilization = 90%

Operator efficiency = 80%

The weekly available capacity at the above work center

is (rounded to the nearest whole standard hour):

A) 50

B) 55

C) 58

D) 60

The correct answer is C)

Available capacity is calculated: 2 machines x 1 shift x 4

days x 10 hours x .90 utilization x .80 operator efficiency =

57.6.

16-1The process of finishing product A at work center 101

has just been completed. In order to prepare for

running product B at this workstation, different tooling

must be installed. This process is called:

A) Interoperation time

B) Changeover

C) Tooling reconfiguration

D) Queue time

The correct answer is B)

A changeover is the process of re-fitting equipment to

offset the effects of the previous production and/or get the

work center ready for the next production.

16-2A bottleneck operation can be best defined as:

A) An operation where work arrives faster than can be

completed

B) The place where emergency maintenance is often

needed

C) The work center which begins the production

process

D) The gateway work center for counting

The correct answer is A)

The work center where work arrives faster than can be

completed is the bottleneck. By concentrating on

alleviating the bottleneck, capacity can often be increased,

as all downstream operations can only complete work

released at the bottleneck rate.

16-3Which of the following would best describe the term

dedicated capacity?

I. A machine which is designated to produce only one

item

II. Special equipment designed specifically to produce a

small group of items

III. The 20% committed capacity a customer has taken

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is A)

Dedicated capacity refers to the way work centers have

been assigned to manufacture specialized products.

16-4Which of the following could be causes of idle time?

I. Maintenance

II. Set-up

III. Training

A) I and II

B) I and III

C) II and III

D) I, II, and III

The correct answer is D)

Idle time or down-time results when machines or operators

are not producing product for a number of reasons

including training, set-up, and maintenance.

16-5Which of the following statements are true regarding

Just-in-Time production?

I. Only refers to the delivery of products when needed

II. Refers to the elimination of waste - "If it doesn't

add value, it's waste; eliminate it"

III. It is a pull system

A) I and II B) I and III

C) II and III D) I, II and III

The correct answer is C)

Many people believe it is only a "delivery of material as

needed" system. It is a philosophy of waste elimination

and worker involvement. Additionally, work is pulled

through the factory based on demand.

17-1Based on the following labor hours information,

calculate the labor efficiency for the week based on an

8 hour shift (times are expressed in hours).

Day 1 Day 2 Day 3 Day 4 Day 5

Set up time . .75 1.0 1.0 1.25 1.50

Run time 6.25 5.5 5.5 5.50 6.25

Wait time . 1.00 1.5 l.5 1.25 .25

A) 72.5% B) 86.25%

C) 91.25% D) 95.00%

The correct answer is B)

Labor efficiency is calculated by dividing the direct time

charged to production activities (set up hours & run time

hours) by the clock time available for the activities or

34.5/40 = 86.25%.

17-2If the manufacturing calendar in the manufacturing

system defines weekends as non-work days, then a 35

day lead time is equal to:

A) 5 weeks

B) 6 weeks

C) 7 weeks

D) 9 weeks

The correct answer is C)

Establishing the manufacturing calendar by defining

weekends as non-work days would cause a 35 day

leadtime to be 7 weeks.

17-3Which of the following is true regarding an open order?

I. It is a released manufacturing order

II. It is a scheduled receipt

III. It is an unfilled customer order

A) I and II

B) I and III

C) II and III

D) I, II, and III

The correct answer is D)

An open order can mean any of the above answers,

depending on what module of an MRPII system you are

in. In an order entry module, customer orders could be in

an open state. In terms of manufacturing, an open order

would be a scheduled receipt or a released manufacturing

order.

17-4Which of the following methods is the fastest method

for adding capacity?

A) Hire new people

B) Add another shift

C) Schedule overtime

D) Subcontract work

The correct answer is C)

Scheduling overtime is quicker than any of the options

listed, including subcontracting, which could require sourcing

a contractor. However, overtime is only an option if there

is capacity available.

17-5If the input to a work center is equal to the output

from the work center, then which of the following is

true?

I. Backlogs are constant

II. Lead-time remains constant

III. Lead-time will increase slightly

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is A)

If input equals output, then lead-time and backlogs will

remain constant.

18-1A "healthy" work-in-process inventory can be generally

defined by which of the following statements?

I. Three days

II. Twenty five percent of finished goods

III. The minimum amount needed to smooth

fluctuations in input

A) I B) II

C) III D) I or III

The correct answer is C)

Work-in-process is intended to allow work centers to

operate even with fluctuations in input to the work center.

18-2Which of the following is/are needed in order to

calculate manufacturing lead-times?

I. Routings

II. Interoperation times

III. Component purchase lead time

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is A)

Component purchase lead-time is not included in the

manufacturing lead-time. Manufacturing lead-time would

include order preparation time, queue time, set-up time,

run time, etc.

18-3Given the following information for a work center:

Machines = 3

Operations per shift = 2

Shifts per day = 1

Days worked per week = 5

Hours worked per shift = 8

Machine utilization = 80%

Operator efficiency = 90%

If changing the hours per shift to 10 from 8 creates

108 standard hours, which of the following actions

would have the same effect?

A) Increase machine utilization to 90%

B) Increase operator efficiency to 100%

C) Change to 6 days per week

D) None of the above

The correct answer is D)

None of the answers give the available capacity of 108

which changing to a 10 hour shift does. This is calculated

by multiplying 3 machines x 50 hours x .80 machine

utilization x .90 operator efficiency. Answer A = 97.2

hours, Answer B = 96 hours, Answer C = 103.7 hours.

18-4Which of the following best describes back scheduling?

A) Start with the current date and calculate the order

due date by the time of each operation

B) Rescheduling jobs where the input is greater than

output

C) Starting with the order due date, calculate the start

date of the order by going back through each

operation

D) Eliminating capacity availability by working back

through the operations

The correct answer is C)

Backward scheduling starts with the order due date and

schedules back through each operations' due date to arrive

at a start date for the order.

19-1Product A can be produced at the rate of 60 per hour

or one each minute. This time is known as the:

A) Standard rate

B) Cycle time

C) Capacity rate

D) Setup time

The correct answer is B)

The cycle time is the time between the completion of two

units of production.

19-2Which of the following is synonomous with detailed

scheduling?

A) Infinite loading

B) Operations scheduling

C) GANTT charts

D) Pert charts

The correct answer is B)

Detailed operation scheduling places start and completion

dates on each manufacturing operation to ensure the

customer due date will be met.

19-3Job ABC will take 100 standard hours to produce.

Using the following information, how many equivalent

days will it take to complete the job (round to the

nearest whole day)?

Machines = 2

Number of operations = 2

Shifts per day = 1

Hours per shift = 8

Machine utilization = 90%

Operator efficiency = 90%

A) 6

B) 7

C) 8

D) 9

The correct answer is C)

There are 12.96 available hours per day (2 machines x 8

hours per day x .90 utilization x .90 efficiency). 100

hours needed/12.96 hours available = 7.72 or 8 days.

19-4Which of the following best describes a focused

factory?

A) A plant where all personnel understand the mission

and objectives

B) A plant which is established to produce a limited

mix of items

C) A plant which has embraced a zero-defect program

D) A plant which concentrates on one job at a time

The correct answer is B)

A focused factory has been set up to run a limited

number of processes or products to allow for an efficient

flow of materials. This can be focused within a larger

physical factory.

20-1Four-wall inventory control with JIT would most likely

include which of the following practices ?

A) Increased dependence on cycle counting for

inventory record securacy

B) ABC analysis on a frequent basis

C) Increased volume of transactions in and out of

inventory

D) Backflushing to reflect material usage

The correct answer is D)

20-2The most likely reason for both marketing and

operation to resist implementing JIT practices is

A) Reduced finished goods inventory levels

B) Emphasis on production efficiencies

C) Shorter manufacturing lead time

D) The change to the relationship between marketing

and operation

The correct answer is D)

20-3Which of the following are true regarding a limiting

operation?

I. It is the operation with least capacity

II. It defines the capacity of the line

III. It is the bottleneck

A) I and II B) I and III

C) II and III D) I, II, and III

The correct answer is D)

A limiting operation is synonomous with bottleneck, as it is

the operation with least capacity. This allows the line to

be scheduled by this operation as the line capacity can

only be as great as the operation with least capacity.

20-4A supplier is responsible to provide 100% acceptable

quality to the customer. This is called:

A) Total quality management

B) Statistical process control

C) Quality at the source

D) Total quality control

The correct answer is C)

Quality at the source requires 100% acceptable quality to

be delivered to the customer. This may be an element of

total quality management or the vendor may use statistical

process control to achieve the result; however quality at

the source defines this example.

20-5The total time included in an operation's duration

includes all of the following EXCEPT:

A) Set-up time

B) Wait time after completion

C) Run time of operation

D) Tooling

The correct answer is B)

Wait time after completing a job would not be included in

the operation's duration.

ACFUN正式会员答题题库(全答案)

1、关于意见反馈，一下说法不正确的是？A A、意见反馈需要登录才能反馈B.用户可以直接咨询客服 C.存在反馈快捷通道 D.意见反馈和举报效果一样 2、一下四个著名的动画业界人士，没有在动画业界童话《白箱》里出现过的是A A. 富野由悠季 B.庵野秀明 C.南雅彦 D.石川光久 3、《南方公园》中拥有无限复活能力的角色是？D A.斯坦 B.凯尔 C.卡特曼 D.肯尼 4、游戏《无主之地》系列中，帅哥杰克的面具下隐藏着？B A.外星人脸 B.秘藏标识 C.一模一样的脸 D.魔女的标识 5、评论才是本体？C A.下体 B.三体 C.本体 D.扁桃体 6、韩国男子组合bigbang的MV…love song?，采用了一连贯的长镜头组成，但有一个破 绽可以看出是MV后期合成的，这个破绽是？ A.崔胜贤的项链 B.姜大成的西装 C.权志龙的手表 D.东永斐的皮鞋 7、北斗之萨样指的是哪位日本声优？A A后藤邑子 B.后藤纱里绪 C.佐藤利奈 D.新井里美 8.一下哪位男性没有喜欢过吉安娜?普罗德摩尔？B A.阿尔萨斯 B.伊利丹 C.凯尔萨斯 D.萨尔 9、“葛炮”的原型人物，曾为哪部动画配音？C A.喜洋洋与灰太狼 B.熊出没 C.蓝猫淘气三千问 D.西游记 10、织田信长的绰号为？C A.第四天魔王 B.第五天魔王 C.第六天魔王 D.第七天魔王 11、A战的“阿婆主”指的是？C A.下载视频的人 B.观众 C.投稿的人 D.管理员 12.一下作品不属于漫画家岩明均所著的是D ？ A.七夕之国 B.历史之眼 C.寄生兽 D.无限之住人 13.导演水岛精二最近的一部剧场版动画名字是D ？ A.裸之催眠术师 B.EXODUS C.第三飞行少女队 D.乐园追放 14、一下LOL里没有中国元素的英雄是？B A.齐天大圣 B.无极剑圣 B.盲僧D.德邦总管 15、2015年“这本小说真厉害”第一名的小说中，黑长直女主角头发上扎了几个蝴蝶结？

高频电子线路试题及答案 (1)

一、填空题 1. 丙类功放按晶体管集电极电流脉冲形状可分为__欠压、__临界__、__过压__ 三种工作状态，它一般工作在___临界____ 状态。 2. 振荡器的主要性能指标_频率稳定度_、_振幅稳定度_。 3. 放大器内部噪声的主要来源是__电阻__和__晶体管__。 4. 某发射机输出级在负载RL=1000Ω上的输出信号Us(t)=4(1+0.5cosΩt)COSWctV。试问Ma=__0.5__，Ucm=__4V__，输出总功 率Pav=__0.009W_ 。 5. 实现频率调制就是使载波频率与调制信号呈线性规律变化，实现这个功能的方法很多，通常可分为__直接调频__和__间接调频___ 两大类。 6. 相位鉴频器是先将调频信号变换成__调相-调频__信号，然后用___相位检波器___进行解调得到原调制信号。 二、选择题 1. 频率在1.5—30MHz范围的短波主要依靠（C ）方式传播。 A 沿地面传播 B 沿空间直线传播 C 依靠电离层传播 2. 在实际振荡器中，有时会出现不连续的振荡波形，这说明振荡器产生了周期性的起振和停振现象，这种现象称为（B ）。 A 频率占据 B 间歇振荡 C 寄生振荡 4. 集成模拟相乘器是（B ）集成器件。 A 线性 B 非线性 C 功率 5. 自动增益控制电路是（A ）。 A AGC B AF C C APC 三、分析题（共4题，共45分） 1. 通信系统中为什么要采用调制技术。（8分） 答：调制就是用待传输的基带信号去改变高频载波信号某一参数的过程。 采用调制技术可使低频基带信号装载到高频载波信号上，从而缩短天线尺寸，易于天线辐射，实现远距离传输；其次，采用调制可以进行频分多路通信，实现信道的复用，提高信道利用率。 2.晶体振荡电路如图1所示，若f1为L1C1的谐振频率，f2为L2C2的谐振频率，试分析电路能否产生自激振荡。若能振荡，指 出振荡频率与f!、f2之间的关系。（12分） +V CC 答：由图可见电路可构成并联型晶体振荡器。由于并联型晶体振荡器中，石英晶体起电感元件作用，所以要产生自激振荡，L1C1并联回路与L2C2串联回路都必须呈容性，所以，WL1 > 1/WC1即f > f1，WL2 < 1/WC2即f < f2，振荡频率f与f1、f2之

acfun题库310道题(2015.6)

1、关于意见反馈，一下说法不正确的是？D A、意见反馈需要登录才能反馈 B.用户可以直接咨询客服 C.存在反馈快捷通道 D.意见反馈和举报效果一样 2、一下四个著名的动画业界人士，没有在动画业界童话《白箱》里出现过的是A A. 富野由悠季 B.庵野秀明 C.南雅彦 D.石川光久 3、《南方公园》中拥有无限复活能力的角色是？D A.斯坦 B.凯尔 C.卡特曼 D.肯尼 4、游戏《无主之地》系列中，帅哥杰克的面具下隐藏着？B A.外星人脸 B.秘藏标识 C.一模一样的脸 D.魔女的标识 5、评论才是本体？C A.下体 B.三体 C.本体 D.扁桃体 6、韩国男子组合bigbang的MV‘love song’，采用了一连贯的长镜头组成，但有一个破绽可以看出是MV后期合成的，这个破绽是？C A.崔胜贤的项链 B.姜大成的西装 C.权志龙的手表 D.东永斐的皮鞋 7、北斗之萨样指的是哪位日本声优？A A后藤邑子 B.后藤纱里绪 C.佐藤利奈 D.新井里美 8.一下哪位男性没有喜欢过吉安娜?普罗德摩尔？B A.阿尔萨斯 B.伊利丹 C.凯尔萨斯 D.萨尔 9、“葛炮”的原型人物，曾为哪部动画配音？C A.喜洋洋与灰太狼 B.熊出没 C.蓝猫淘气三千问 D.西游记 10、织田信长的绰号为？C A.第四天魔王 B.第五天魔王 C.第六天魔王 D.第七天魔王 11、A战的“阿婆主”指的是？C A.下载视频的人 B.观众 C.投稿的人 D.管理员 12.一下作品不属于漫画家岩明均所著的是 D ？ A.七夕之国 B.历史之眼 C.寄生兽 D.无限之住人 13.导演水岛精二最近的一部剧场版动画名字是D ？ A.裸之催眠术师 B.EXODUS C.第三飞行少女队 D.乐园追放 14、一下LOL里没有中国元素的英雄是？B A.齐天大圣 B.无极剑圣 B.盲僧 D.德邦总管 15、2015年“这本小说真厉害”第一名的小说中，黑长直女主角头发上扎了几个蝴蝶结？C

汽车发动机原理试题库及答案

一、发动机的性能 一、解释术语 1、指示热效率：是发动机实际循环指示功与消耗燃料的热量的比值. 2、压缩比：气功容积与燃烧室容积之比 3、燃油消耗率：发动机每发出1KW有效功率,在1h内所消耗的燃油质量 4、平均有效压力：单位气缸工作容积所做的有效功 5、有效燃料消耗率：是发动机发出单位有效功率时的耗油量 6、升功率：在标定工况下，发动机每升气缸工作容积说发出的有效功率 7、有效扭矩：曲轴的输出转矩 8、平均指示压力：单位气缸容积所做的指示功 2、示功图：发动机实际循环常用气缸内工质压力P随气缸容积V（或曲轴转角）而变化的曲线 二、选择题 1、通常认为，汽油机的理论循环为（ A ） A、定容加热循环 B、等压加热循环

C、混合加热循环 D、多变加热循环 6、实际发动机的膨胀过程是一个多变过程。在膨胀过程中，工质（ B ） A、不吸热不放热 B、先吸热后放热 C、先放热后吸热 D、又吸热又放热 2、发动机的整机性能用有效指标表示，因为有效指标以（ D ） A、燃料放出的热量为基础 B、气体膨胀的功为基础 C、活塞输出的功率为基础 D、曲轴输出的功率为基础 5、通常认为，高速柴油机的理论循环为（ C ） A、定容加热循环 B、定压加热循环 C、混合加热循环 D、多变加热循环 6、实际发动机的压缩过程是一个多变过程。在压缩过程中，工质（ B ） A、不吸热不放热 B、先吸热后放热 C、先放热后吸热 D、又吸热又放热

2、发动机工作循环的完善程度用指示指标表示，因为指示指标以（ C ） A、燃料具有的热量为基础 B、燃料放出的热量为基础 C、气体对活塞的做功为基础 D、曲轴输出的功率为基础 2、表示循环热效率的参数有（ C ）。 A、有效热效率 B、混合热效率 C、指示热效率 D、实际热效率 3、发动机理论循环的假定中，假设燃烧是（ B ）。 A、定容过程 B、加热过程 C、定压过程 D、绝热过程 4、实际发动机的压缩过程是一个（ D ）。 A、绝热过程 B、吸热过程 C、放热过程 D、多变过程 5、通常认为，高速柴油机的理论循环为（ C ）加热循环。 A、定容 B、定压 C、混合 D、多变

高频电子线路试题库

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