Short- Term Scheduling

(Theory, Issues, and Processes)

Done by:

•Paula Caballero

•Alvaro Terry

1. The Importance of Short-Time

Scheduling

``Scheduling concerns the allocation of limited resources to

tasks overtime.'' (Pinedo 1995)

Example:

Airlines (eg: Delta Airline) try to expect the unexpected Weather

Bad weather caused 10% of flights cancelations Looses of 440

M$

Solution An investment of 33M$ in High-Tech Nerve Center

“Its function is to reallocate the passengers as soon as possible to

maintain their level of satisfaction”

1. The Importance of Short-Time

SchedulingExample video:

https://www.youtube.com/watch?v=kOw-Fyk5X_c

1. The Importance of Short-Time

Scheduling

Delta ( Schedules/daily) 753 aircrafts + 10,000 pilots and flight attendants

Good Scheduling = Customer Satisfaction

Objective: Allocate and prioritize demand, matching daily or hourlyrequirements to specific personnel and equipment

A Good scheduling approach shoulg be simple, clear, easily understood, easy to carry out, flexible and realistic

Strategic Importance: Effective Scheduling ( fast movement of G/S, decrease of costs)

Added Capacity , Faster Performance and Flexibility (faster delivery)

Good Scheduling (realistic commitments and dependable delivery)

Schedule Decissions:

1. The Importance of Short-Time

Scheduling

2. Other examples

3. Forward and backward

schedulingForward: begins the schedule as soon as possible as the

requirements are known (…). Customized products that are

needed as soon as possible.

Backward: Begins with the due date of the final operation. The

resources neccesary to accomplish the schedule may not

exist

Examples: Hospitals, Clinics, Machine

tool manufacturing, Restaurants

Examples: Banquet, catering, scheduling

surgery, service environment

4. Scheduling Issues

Most common case is to find an organization with a mix of

both applied.

Even having the date scheduled; the elaboration process

could fail because of………………., so it does not ensure that

the G/S will be ready.

Could you think about any factor

that complicates scheduling?

Weather, Absenteeism, Machine breakdown

Workers falling asleep, Shortage

5. Goals of Short-term

scheduling

Minimize completion time (average of production time

Maximize utilization (percentage of time the facility is

used)

Minimize Work-in-Process (WIP) to reduce inventories

( average number of jobs in the system)

Minimize customer waiting time (average of late days)

All these goals depend on the volume of the orders,

nature of the operations, and the complexity of the jobs.

6. Scheduling Process-

Focused Facilities

This system should…

1. Schedule incoming orders without exceeding capacity

2. Check availability of tools and materials before releasing an order (raw materials)

3. Establish due dates for each job and check progress

4. Provide feedback

5. Provide work efficiency to increase employees motivation

Process focus facilities are compound of high variety

and low volume systems (manufacturing and service

organizations) in which products are made to order

Revising…

Question 1

1. Could you tell me 2 factors that could lead to the

disruption of airlines schedules

Weather

Absenteeism

Machine breakdown

Workers falling asleep

Shortage

Question 2

Could you give me 2 examples of forward scheduling?

Hospital

Clinic

Machine tool manufacturing

Restaurant

Question 3

3. Which is a characteristic of good scheduling?

a) Clear

b) Simple

c) Flexible

d) All of the above

Correct answer:

d) All of the above

Question 4

4. Which of these factors do not contribute to the

strategic importance of scheduling?

a) Added capacity

b) Independent delivery

c) Effective scheduling

Correct answer:

b) Independent delivery

Question 55. Which of these statements is False concerning the strategic

importance of sheduling?

a) Added capacity and the related flexibility mean faster

delivery and better customer service

b) Added capacity and the related simplicity mean faster

delivery and better customer service

c) Effective scheduling means faster movement of goods and

services through a facility

d) Effective scheduling means greater use of assets and hence

greater capacity per dollar invested

Correct answer:

b) Simplicity

Question 6

6. Short-term schedules translate capacity decisions, aggregate

planning, and master schedules into job sequences and

specific assignments of personnel, materials and machinery.

a) True

b) Flase

Correct answer:

a) True

Question 7

7. Scheduling goods and services in the short run involve

matching daily or hourly requirements to specific personnel and

equipment

a) True

b) Flase

Correct answer:

a) True

Question 8

8. Which 2 types of scheduling have we seen in this

chapter?

a) Forward and backward scheduling

Question 9

8. Manufacturing firms do not have to deal with the problem of

short-term scheduling

a) True

b) Flase

Correct answer:

a) False

Question 10

10. Can you tell me at least one goal of short-term

scheduling?

Minimize completion time

Maximize utilization

Minimize work-in progress inventory

Minimize customer waiting time

Question 11

3. If something happens on the day of operations you are able

to recover from that disruption without throwing your schedule

away and thus spending more money to trying to cover the

flight. This statement is talking about?

a) Schedule simplicity

b) Schedule robustness

c) Schedule capacity

Correct answer:

b) Schedule robustness

Question 12

12. Mining does not have to deal with the problem of short-term

scheduling:

a) True

b) False

Correct answer: b) False

Question 13

13. Choose the wrong answer: Specialized techniques have

been developed to aid in preparing reliable schedules…

a) As assignment of a date does not ensure that the work will

be performed according to the schedule

b) In order to be 100% sure that the schedule will be perfectly

executed

c) Because schedules are an essential factor that contributes to

the efficiency of the company

Correct answer:

b)

Question 14

14. Which statement is False?

a) Focused facilities are compound of low variety and low

volume systems (manufacturing and service organizations)

in which products are made to order

b) Focused facilities are compound of high variety and high

volume systems (manufacturing and service organizations) in

which products are made to order

c) Focused facilities are compound of high variety and low

volume systems (manufacturing and service organizations) in

which products are made to order

Correct answer: c)

Thank you for your attention!