System Engineering
7.9 a.Develop a set of operational requirements for a simple lawn tractor.Limit yourself to no more than 15 operational requirements.
7.9.b.Develop a set of performance requirements for the same lawn tractor.
7.9.d.How would you go about validating the requirements in (b)?
Operational Requirements
Define the operational conditions or properties that are required for the system to operate or exist. This type of requirement includes: human factors, ergonomics,
availability, maintainability, reliability, and security.
Performance Requirements
Define quantitatively the extent, or how well, and under what conditions a function or task is to be performed (e.g. rates, velocities). These are quantitative
requirements of system performance and are verifiable individually. Note that there may be more than one performance requirement associated with a single function,
functional requirement, or task.
8.4 Under the subsection Program Risks, five examples are listed of conditions that may result in a significant probability of program failure. For each example,
explain briefly what consequences of the condition may lead to a program failure.
Part 2: Replay and comment to these answers.
1)
1.5) Firstly, the Pro points related to the incorporation of some of the latest technology to the development of a new complex system are
Pros:-
The technological impact on the complex system has resulted in increasing the capabilities of the prevailing ones. The consequences can be seen in terms of the output
it is giving.
The automobiles which are made handmade initially, gradually evolved to a place where the products are now fully machine made with the human interaction so that the
products are cost efficient, led to mass production and reduced the human labor.
Cons:-
Without the broad knowledge of the technology and approaching the system may result in difficulties that lead to product execution failure or the consequences may go
even worse.
Many times maintaince is not done properly due to incomplete knowledge of the system.
1.8) It is true system engineers are advocate for the whole of the system and should tke care of all the stakeholders involved in system.
Stakeholders here can be defined as people with whom the system engineers have to work with or work for and also the organizations for which they have to work.
For example, in an IT firm, these system engineers are masters of technology and also have functional knowledge of the system they are supporting. In this case the
stakeholders are the clients & the organization for whom the project has been taken, the mangers and the organization for whom the system engineer is an employee may
also be considered as stakeholders in this case.
2)
1.5
List four pros and cons (two of each) of incorporating some of the latest technology into the development of a new complex system. Give a specific example of each.
It is very important to use the latest technology into the development of new complex systems.
Pros:
Developments can be life changing for those who use these systems and make processes much easier
The development of software technology has led to an increase in automation in factories, offices, and even hospitals making it easier for everyone including
companies, employees, and even clients/patients who do not actually use the software.
Automation has revolutionized many industries
Solves a particular need and uses advanced technology such as automated navigation and autonomous driving and parking.
Cons:
Large sums of money is important
It is important to know how a change can impact the business and the industry and how long a project will take to make active. There will be development risk.
Risk of not being the first to the market
Since everyone is trying to make a better product that the competitor, speed to market is important because it can delete all the hard work one company has done since
it will overlap.
1.8
Systems engineers have been described as being an advocate for the whole system. Given this statement, which stakeholders should the systems engineer advocate the
most?
The systems engineer works with many different and technical team members. Stakeholders are usually the people that are using the system and that will be the clients
or people around the technology. If there is an update on the website or a new system exists, the people will be the ones that rate everything and they will see what
changes that need to be made if any.
3)
2.3 Select a very large complex system of system example and explain how the engineering systems approach could provide useful solutions that would have wide
acceptance across many communities.
banks have too many systems that works together to complete each other for example IT production. Marketing, ATM networks, and stocks market. And i believe systems
engineering has a big hand of experience for supporting highly available networks for banking industry. Systems engineering works with the banking clients to ensure
their core banking applications. ATM networks are always available for them. Also, it will ensure the successful deployment and support of your critical applications.
Moreover, delivering project management services to complete projects on time and on budget.
4)
2.3 Select a very large complex system of system example and explain how the engineering systems approach could provide useful solutions that would have wide
acceptance across many communities.
Large complex systems require a high-level degree of analysis, security and logical output. In order to achieve that, it requires various steps that the engineering
systems approach takes. One specific large complex system is found in telecommunications. As simple as we might now see it to be, it requires significant complex
networking and engineering. A simple way of making a phone call can be done anywhere in the world at any time without a significant delay. We can be on a moving plane
at 40,000 feet and our communication easily goes through. This complex system has been adapted by almost everything in the world. Our way of communicating has changed
dramatically, and it is because of telecommunications. The systems engineering approach such as requiring a goal, function, design, analysis and integration has helped
reach more people and more systems across the globe.
5)
3.5 Referring to Figure 3.4, for each of the environments and interfaces illustrated, (1) list the principal interactions between the environment and the aircraft, (2)
the nature of each interaction, and (3) describe how each affects the system design.
1. Flight environment– the flight environment communicates with the aircraft concerning any obstacles, bad weather conditions or barriers when flying. The update
signals regarding any issues are constantly updated to the control tower which in turn informs the pilot.
2. Landing environment– the main purpose of the beacon is to give data signals concerning the plane’s speed and its elevation from the ground. This data in turn helps
the pilot to make informed decisions when landing.
3. Support environment– the flight requires power and fuel when flying. The cabin crew updates the support which the refiles the airplane when still airborne.
4. People and Payload interface – before the journey begins, a list of all passengers must be given to the flight and ground staff. This list helps in passenger
identification and counterchecking if any have been left behind. The list further corresponds to the ticket sale. The list and ticket sales further help the support
staff to estimate the payload capacity; in case the plane is not loaded to capacity, then the passengers are permitted to carry extra luggage for free above the set
limit. Also, in case the passengers are full to capacity, the luggage they carry might be limited.
5. Maintenance teams – when the plane is airborne, the crew notes the emerging defects or issues and informs the maintenance team when the plane lands. The maintenance
team then repairs these defects before the plane proceeds to the next journey.
4.9 Select one of the household appliances listed below:
automatic dishwasher
washing machine
television set
(a)State the functions that it performs during its operating cycle. Indicate the primary medium (signals, data, material, or energy) involved in each step and the
basic function that is performed on this medium.
Television set
Functions performed by a television:
• Picking up radio signals using the antenna from the transmitter – Signal
• Signals are sent to the TV using a fiber optic cable – Signal
• Stating the Electronic circuit (EC) by switching on the power – Energy
• Selecting a channel – Energy
• The file transfer signal is transferred by the modulator to the amplifier – Data
• The loudspeaker is driven by the audio circuit – Material
(b)For the selected appliance, describe the physical elements involved in the implementation of each of the above functions.
Physical elements:
• The antenna is used to pick up radio signals
• Electronic circuit helps to switch on the TV
• Fiber optic cable assists in sending signals to the TV
• The Audio circuit helps to drive the loudspeaker
• Cathode Ray Tube helps in transmitting colored signals
• Modulator and demodulator
• TV screen
6)
Problem 3.5:
There are two types of environmental interactions, which include primary and secondary interactions. Primary interactions are basically the interaction with the
system’s main purpose such as the inputs, outputs, and controls and the secondary interactions are the systems that relate indirectly like the temperature. The
materials in this example are the clients on the plane and what they have on the plane with them and the way they arrive to their destination. Since the input does not
change the way the plane works it is a secondary interaction, since with the definition is indirect. The way it affects the system design is by carrying the passengers
and receiving information indirectly. When flying the plane, it is very different since the pilot puts in an action to receive a reaction with these interactions. In
this example there are three separate parts; the interaction between the plane and the flight environment, the plane and the landing environment, and the plane and the
support environment that assists the plane for its next trip.
The interaction between the plane and the flight environment is secondary but the flight commands can help in times of rain, winds, and turbulence. The interaction
between the landing environment and the plane is primary because there is direct communication with the brakes when coming to a stop and opening the landing gear. The
interaction between the support environments is primary because systems have to be checked for safety and security.
Problem 4.9
There are many household appliances other than the ones in the question that have a system cycle. I chose the television set to be an operating cycle because it shows
video and you can hear audio as well. The system that connects the TV and allows it to work is the cable and electricity also known as giving it energy. There are many
controls on a TV but the important one is turning the TV on and off, and like my TV, has a connection to different game systems by using Bluetooth or Wifi. Sometimes
certain wires are necessary for connecting the devices such as HDMI cables, audio cables for an external audio connection, and even sometimes an internet cable has to
be hard wired and cannot use Bluetooth.
7)
5.9 Research the building of the tunnel under the English Channel in the late twentieth century.
(a)What risks were present with this project?
1- Financing for this project. These large projects are known to be funded by the government.
2- Tunnel fires. They were common during construction and also occurred when construction was completed.
3- Fears of collapse. It can be caused by earthquakes or high wave or soft marl used to build the tunnel to prevent possible collapse due to the number of trains
operating daily.
4 – Non-convergence of the sides of the tunnel. Because of the lack of communication between the two companies based on the project.
(a)What successful activities were undertaken to mitigate these risks that led to the tunnel’s completion?
1- The banks solved the problem of insurance through loans and shares, and an amount of approximately £ 6 million was raised.
2- The problem of Tunnel fires was solved through the construction of a third tunnel called the safety tunnel that helps transport workers and passengers during a fire
(Channel tunnel, 2006).
3 – The problem of collapses was solved by the number of trains distributed by the load on the three tunnels that were established, and the use of high-pressure
tolerance materials (Further, Bridge 2001).
4 – The problem of drilling in the same direction was solved by using cadastral devices with the ability to accurately locate, which in turn helped to complete the
project
8)
The Channel Tunnel: Risks Involved
The channel tunnel commonly referred to as the Chunnel is a tunnel connecting England and France running through the English Channel. The tunnel, which is 50 km long,
comprises of three passages in that two rails are for traffic while the other one is for security and service (Redford, 2014). The construction of the Chunnel began in
1988, completed in 1992, and was officially opened in 1994. However, despite the successful completion of the tunnel, so many risks and dangers were involved. The
construction TML had to come up with various strategies to ensure there were few or no risks involved.
Among the many risks involved in the building of the Chunnel, Personal injury was the outstanding risk. The construction of the tunnel involved activities such as
digging of the tunnel, handling heavy metals, carrying and moving trains, among others. These activities could lead to back strains, muscle tear, and sometimes head
injury due to falling objects (Redford, 2014). In solving such issues, TML came with Emergency reporting protocol to ensure that injured workers got timely and
efficient medication. Secondly, the construction team were availed with protection materials such as helmets, gumboots, gloves, protective goggles, dust masks, and
aprons to reduce the risk of personal injuries.
To add on, communication between the two teams, France and British, who had agreed to meet in the middle proved to be a risk to the project. With two different teams
on the same project, communication proves to be important to the project. At one point, the project delayed because of poor and delayed communication on the
construction of the tunnel (Redford, 2014). However, the TML came up with a communication protocol that aimed at reporting the progress and arising issues. This helped
in timely decisions and created a strong connection between the two teams.
9)
6.6 Assume that you have a business in garden care equipment and are planning to develop one or two models of lawn tractors to serve suburban homeowners. Consider the
needs of the majority of such potential customers and write at least six operational requirements that express these needs. Remember the qualities of good requirements
as you do so.
The lawn tractor shall have a suitable space for lawn equipment.
The lawn tractor shall cut out the area that is not even.
The lawn tractor shall make the working time around 5 hours per day.
The lawn tractor shall be designed in a way that could be workable for driver or owner.
shall carry a reasonable weight.
The lawn tractor shall should be confrontable for passenger to avoid any harm movement.
10)
A business such as lawn care must be fully organized in order to execute because there are many factors that can have both advantages and disadvantages. When looking
at suburban residential land, this means that homes have more land than urban areas, so it is important that lawn care companies are fully equipped.
Since these tractors are going to be treating large areas of land, it is necessary that the run time for these tractors to be about 5 hours or more and that they work
the entire period of time that an operate is able to work. The machines can rest or recharge when the operator is on break or done for the day.
These tractors should be able to handle all types of land and can make sharp turns because it is important to go around trees in suburban areas.
The tractor should be comfortable enough to operate the machine for at least 5 hours a day and not have a hard time controlling the tractor
The tractor should be able to carry a large load of approximately 400 pounds which includes the operator, tools, gasoline, etc
The tractor should be large enough to carry the operator, tools, gasoline etc
The lawn tractors should be easy to fix and replace parts just in case something happens while cutting large areas of grass and land
The lawn tractors should also run quickly so the operators will be able to be efficient
The lawn tractors should also have large fuel tanks so the operators will not need to refuel them as quickly
11)
(a) Develop a set of operational requirements for a simple lawn tractor. Limit
yourself to no more than 15 operational requirements.
Operational requirements for a simple lawn tractor are:
1. E ffective knife stroke
2. Effective cutting height
3. Sufficient working width
4. Knife speed
5. Knife forward speed
6. Crank speed
7. Ratio of speed
8. Sufficient filed capability
9. Filed efficiency
10. Sufficient harvest capability
11. Economic fuel consumption
12. Effective in all weather
13. Rotating blades
14. Lights to work in the dark
(b) Develop a set of performance requirements for the same lawn tractor.
Limit yourself to no more than 30 performance requirements.
Performance requirements for a simple lawn tractor are:
1. H igh quality knife to cute efficiently
2. Capacity to move knife to change cutting depth
3. Rotation of blades to maximize efficiency
4. Setting of speed to make it high/low
5. Effective materials to sustain quality of parts
6. Cost-effective fuel usage system
7. Cover all running parts to prevent damage
8. Effective light system to perform in the shaded areas
9. Light-weight to move is easily
10. Easy and safe to use in all weather
11. Knife need to be stop in minimum time
12. Guards on the blades
13. Proper lubrication of the running parts
14. Efficient ignition for start it
15. Distance meter to cut grass with required length
16. Gear system to manage its speed
17. Sufficient blade control system
18. High quality color and finishing
19. Sufficient sitting capacity
20. Easy to operate and signal
21. Overall high efficiency in all operations
(d) How would you go about validating the requirements in (b)?
To validate the requirements, I make comparison between operational requirements and performance requirements. I analyze its operations and performance to make it
time-effective and cost-effective.
12)
a. Develop a set of operational requirements for a simple lawn tractor. Limit yourself to no more than 15 operational requirements.
Operational requirements for a simple lawn tractor can include:
Durable blades that stay sharp.
Good motor.
Safety protection.
Good size gas tank.
Transmission that is durable.
Comfortable seating.
Easy to maneuver.
Protection from natural elements.
Easy accessibility for parts replacement.
Energy and noise efficiency.
(b) Develop a set of performance requirements for the same lawn tractor. Limit yourself to no more than 30 performance requirements.
Performance requirements for a tractor can include:
Adjustable blades that can be lowered or raised.
Adequate speed.
Spare tire on board that can easily be changed.
Easy shifting of gears.
Proper maintenance schedule.
Operator instructions.
Minimum and Maximum levels of grass that can be cut.
Monitoring system.
(d) How would you go about validating the requirements in (b)?
To validate the requirements from answer B, it will require regularly scheduled test and downtime practices to ensure all the areas are performing at an optimal level.
For example, to ensure the grass is being cut properly, you should evaluate the length of the grass that was cut and see the blade or blade level needs to be adjusted.
Another example would be checking the spare tire regularly to ensure it is inflated. All systems need to have checks and regular tests.
13)
Conditions That Could Cause Program Failure
Program failure can be cause by several reasons. The reasons that could result to program failure. Applying a leading edge technology is one of the issues that could
lead to a failed program. Leading edge is the use of a relatively new technology that is not proven to test if it has any strategic benefit to the company (Scurlock,
2018). Using unproven technology could result into program failure as it has no guarantee that it is risk free. If a major performance increase is required, the
program has to have the ability to adapt to the required performance increase. The program could fail if the program is not able to handle the raised performance.
A program requires some specific conditions in order to function optimally. If a decrease in cost is required and the performance of the program needs to be the same
as before, this would mean regulation of some conditions. A program is likely to fail because this would mean that the output is expected to be higher while the
conditions are regulated, ‘overloading’ it. Postulating an operating environment that is significantly more severe than normal could also lead to program failure. The
more severe environment could cause the program to fail because it could change the functioning of the program, affecting the way it functions. If the environment is
altered severely, the operation of the program will be affected too, and it could lead to failure. Lastly on the possible causes of program failures, is imposing an
unduly short schedule of development. The development schedule of any program should have an adequate development time so that all risks can be recognized and solved.
If a risk passes unnoticed because of a hurried development, it could crash the program and therefore lead to a failure.
14)
Problem 8.4:
Under the subsection Program Risks, five examples are listed of conditions that may result in a significant probability of program failure.
• A leading – edge unproven technology is to be applied: the application of new technology can bring a lot of benefits; however, unproven technology is one of a reason
of project failure. Unproven technology means that it is not tested and validated and applied in the practical project causing of high risky factor. This can link to
the wrong estimation in project cost, labor, equipment etc. In addition, there is no standard for unproven technology leading to failure in operating, performance,
safety etc.
• A major increase in performance is required: the increase of performance is one of the key factors that need to be considered in project management. For example,
wastewater treatment plant (WWTP) at DMV was designed to treat 300 MGD; however, the urbanization leads to the increase significantly of wastewater treatment in the
next 2 years to 400 MGD. So, the WWTP has to make a decision to deal with that issue (new technology/ build more plant … to increase the treatment capacity). If not,
they will fail in the requirements of performance quality. This is an example about the major increase in performance to project failure.
• A major decrease in cost is required for the same performance: at the same performance operated at a constant cost, a major decrease in the cost can be the main
reason of project failure because of the wrong in cost estimation including labor, technology, materials…For example, to build a high rise steel- structure building,
the estimated cost for this project is 300 M$ for a comprehensive budget; however, the cost is reduced noticeably to 200M$. That leads to the contractor and owner have
to deal with the contract about the project requirements, if not, they will fail in project management.
• A significantly more severe operating environment is postulated: This risky factor is related to non-safety related to equipment under postulated environmental
conditions could prevent satisfactory accomplishment of safety function.
• An unduly short development schedule is imposed: in this case the operator and developer may not elaborated together to work on new system. The testing is done by
the developer only, hence an duty short development schedule may be lack of the training time, step by step of practical of implementation…