Login

Contact Us
Homework
Homework Questions? Ask a Tutor for Answwers ASAP
Not a Homework Question?
How JustAnswer Works:
Ask an Expert
Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
Get a Professional Answer
Via email, text message, or notification as you wait on our site.
Ask follow up questions if you need to.
100% Satisfaction Guarantee
Rate the answer you receive.
Ask akch2002 Your Own Question
akch2002
,
Engineer
Category:
Homework
Satisfied Customers:
2816
Experience:
Home work expert
46493125
Type Your Homework Question Here...
akch2002 is online now
The differential equations for constant harvest and constant
Resolved Question:
The differential equations for constant harvest and constant effort models for sustainable harvesting can both be written in a nicer factorised form as follows:
dP/dt = r/K (P  PU )(PS  P)
where P(t) is the population size, r is the intrinsic reproduction rate, K is the carrying capacity, PU is the unstable equilibrium and PS is the stable equilibrium. In this assignment you will derive a formula for the general solution and then use it to calculate the time required for a population to recover from a disaster.
(a) Use separation of variables and partial fractions to determine the general solution to the above differential equation. Leave your solution in implicit form, you do not need to make P the subject.
(b) Now assume that PU < P < PS and show that the general solution can be written in the form
a ln(PPU /PSP) = r/Kt + C
where C is an arbitrary constant. Give an expression for the coffecient a.
(c) The constant harvest model has r = 0:3 per year, K = 3000 kilotons, PS = 1600 kilotons and PU = 1400 kilotons. A disaster has reduced the population close to the unstable equilibrium. Assuming P = 1410 when t = 0 calculate the time taken for the population to reach P = 1500.
(d) The constant effort model also has r = 0:3 per year, K = 3000 kilotons and PS = 1600 kilotons but PU = 0 kilotons. Assuming the same initial condition of P = 1410 when t = 0 calculate the time taken for the population to reach P = 1500 for this model.
Submitted:
1 year ago.
Category:
Homework
Expert:
akch2002
replied 1 year ago.
Can you upload word file of these questions?
Kindly indicate dead line for replying this question.
Ask Your Own Homework Question
Expert:
akch2002
replied 1 year ago.
Kindly write the equation as given in the question.
Ask Your Own Homework Question
Customer:
replied 1 year ago.
The differential equations for constant harvest and constant effort models for sustainable harvesting can both be written in a nicer factorised form as follows:
dP/dt = r/K(PPU )(PS  P)
where P(t) is the population size, r is the intrinsic reproduction rate, K is the carrying capacity, PU is the unstable equilibrium and PS is the stable equilibrium. In this assignment you will derive a formula for the general solution and then use it to calculate the time required for a population to recover from a disaster.
(a) Use separation of variables and partial fractions to determine the general solution to the above differential equation. Leave your solution in implicit form, you do not need to make P the subject.
(b) Now assume that PU < P < PS and show that the general solution can be written in the form
a ln(PPU/PSP) = r/Kt + C
where C is an arbitrary constant. Give an expression for the coefficient a.
(c) The constant harvest model has r = 0:3 per year, K = 3000 kilotons, PS = 1600 kilotons and PU = 1400 kilotons. A disaster has reduced the population close to the unstable equilibrium. Assuming P = 1410 when t = 0 calculate the time taken for the population to reach P = 1500.
(d) The constant effort model also has r = 0:3 per year, K = 3000 kilotons and PS = 1600 kilotons but PU = 0 kilotons. Assuming the same initial condition of P = 1410 when t = 0 calculate the time taken for the population to reach P = 1500 for this model.
Note: A fishing authority would want a plan that allows fast recovery of the fish population while allowing a viable fishing industry. If you have done the calculations correctly you will discover that the recovery time for one of the models is a few years and for the other is over a century.
The deadline is 10/2/2012
Expert:
akch2002
replied 1 year ago.
Thanks. I will reply before due date.
Ask Your Own Homework Question
Expert:
akch2002
replied 1 year ago.
THIS ANSWER IS LOCKED!
You can view this answer by clicking here to
Register
or
Login
and paying $3.
If you've already paid for this answer, simply
Login
.
akch2002, Engineer
Category:
Homework
Satisfied Customers:
2816
Experience:
Home work expert
akch2002 and 4 other Homework Specialists are ready to help you
Ask your own question now
Expert:
akch2002
replied 1 year ago.
Do you require any clarification?
Ask Your Own Homework Question
JustAnswer in the News:
Askadoc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses workfromhome jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
What Customers are Saying:
Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.
Mary C.
Freshfield, Liverpool, UK
<
Last

Next
>
Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.
Mary C.
Freshfield, Liverpool, UK
This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!
Alex
Los Angeles, CA
Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.
GP
Hesperia, CA
I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.
Justin
Kernersville, NC
Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.
Esther
Woodstock, NY
Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.
Robin
Elkton, Maryland
He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.
Diane
Dallas, TX
Meet The Experts:
Manal Elkhoshkhany
Tutor
Satisfied Customers:
4520
More than 5000 online tutoring sessions.
<
Last

Next
>
http://ww2.justanswer.com/uploads/BU/BusinessTutor/201222_115741_Kouki2.64x64.jpg
Manal Elkhoshkhany's Avatar
Manal Elkhoshkhany
Tutor
Satisfied Customers:
4520
More than 5000 online tutoring sessions.
http://ww2.justanswer.com/uploads/LI/lindaus/2012610_04811_IMG20120609164157.64x64.jpg
Linda_us's Avatar
Linda_us
Finance, Accounts & Homework Tutor
Satisfied Customers:
3121
Post Graduate Diploma in Management (MBA)
http://ww2.justanswer.com/uploads/ComputersGuru/20100213_051118_Photo41.JPG
LogicPro's Avatar
LogicPro
Engineer
Satisfied Customers:
3035
Expert in Java C++ C C# VB Javascript Design SQL HTML
http://ww2.justanswer.com/uploads/lanis/200941_233717_phput9xef_c1pm.jpg
Lani S.'s Avatar
Lani S.
Tutor
Satisfied Customers:
2457
Registered Nurse, Internet Researcher, Private Tutor
http://ww2.justanswer.com/uploads/chooser77/20090818_162025_Chris.jpg
Chris M.'s Avatar
Chris M.
M.S.W. Social Work
Satisfied Customers:
2341
Master's Degree, strong math and writing skills, experience in oneonone tutoring (college English)
http://ww2.justanswer.com/uploads/JawaadAhmed/2009627_12137_SIs_SHadi.jpg
F. Naz's Avatar
F. Naz
Chartered Accountant
Satisfied Customers:
1975
Experience with chartered accountancy
http://ww2.justanswer.com/uploads/JK/jkcpa/2011116_182614_jkcpa.64x64.jpg
Bizhelp's Avatar
Bizhelp
CPA
Satisfied Customers:
1873
Bachelors Degree and CPA with Accounting work experience
Related Homework Questions
Question
Date Submitted
I want to use NetBeans to develop a GUI version of an Invoice
8/21/2014
8/22/2014
LogicPro
LogicPro,I just tried to get the solution you created for
8/21/2014
8/21/2014
LogicPro
1) Identify five different materials that you encounter or
8/21/2014
8/21/2014
asciandwildlifebio
I have a document with 7 questions .. below are examples. Would
8/18/2014
8/18/2014
R.R. Jha
See attachment. 2 PHP problems.
8/17/2014
8/18/2014
thepcguy
Sir, The next set. http://www.mediafire.com/view/j9n9x
8/17/2014
8/18/2014
Chris M.
Hey John You answered and completed a design for a previous
8/17/2014
8/19/2014
John
http://wikisend.com/download/615080/Dcarder_GeoCache_72714.zip sorry
8/16/2014
8/17/2014
TheDoctor
for cher only Exam: 250704RR  Neoclassical to Surrealistic
8/16/2014
8/16/2014
Cher
For Chris M. Sir, Excellent work on the first set. Here
8/15/2014
8/17/2014
Chris M.
X
Ask a Tutor
Get a Professional Answer. 100% Satisfaction Guaranteed.
54 Tutors are Online Now
Type Your Homework Question Here...
characters left: