Blog

Learn something new with our collection of blog posts centered around various topics on PSpice® technology.

Lorenz Oscillator- The Lorenz System

“It may happen that small differences in the initial conditions produce very great ones in the final phenomena. A small error in the former will produce an enormous error in the future. Prediction becomes impossible”. Edward Lorenz

 

The meteorologist, Edward Lorenz, in 1961, discovered chaos theory inadvertently whilst modeling atmospheric convection and weather patterns. He published a paper in 1963 where he showed how the model produced chaotic behavior by changing the model from a linear to a nonlinear model. To save time during a simulation run on a very basic desktop computer, he started from the middle of a previous simulation session and to his surprise found the output was completely different from a previous output. By truncating five-digit simulation numbers down to three-digit numbers he discovered one of the principles of chaos theory “Sensitive to Initial Conditions (SIC)”. A small change in initial conditions i.e., reducing the number of places of decimals, produced a bigger change in the system as it evolves. What is often quoted in the literature is Lorenz’s famous quote in a presentation in 1972 to the American Association of Scientific research “Does the flap of a butterfly’s wings in Brazil set off a tornado in Texas”, which illustrates how very small change in the initial condition produces much bigger changes later. Edward Lorenz showed that for chaos to exist in autonomous ordinary differential equation systems, three variables and two quadratic non-linear elements must be present. However, since then the number of variables can be reduced to two for non-autonomous chaotic  system, and one, for discrete chaotic systems. The Lorenz weather system models clockwise and anticlockwise thermal convective air mass rotations in a closed container and the ordinary differential equations used in this model were originally created by Barry Saltzman (1962). Any n-th order nonlinear differential equation can be written as n separate coupled first-order ODEs. For example, the following coupled equations are a reduced form of the Navier-Stokes equations that model the Lorenz chaotic system that we will examine shortly:

 

                                             Lorenz_oscillator_equation1.png

 

By coupled we mean that the equations are linked to each other and the parameters. The original parameter used by Lorenz are: Prandtl number = 10, Rayleigh number, R = 28, and β = B = 8/3 and are all greater than zero. This simplified Lorenz model has since been proved to be chaotic by B Hassard and J Zhang, 1994 but also by Tucker in 1999. The parameters were given these names because Lorenz derived his equations from the Raleigh-Bénard convection flow (convection in a liquid heated in a container from below, generates Bénard cells). We rewrite these equations in a different form shortly, where we will express the variables as a function of time and introduce initial conditions. The Lorenz equations represent the movement of a horizontal layer of a fluid like air, being heated from below. The speed of the rising air mass, x, is positive for clockwise rotation and negative for anti-clockwise rotations. The temperature difference between descending and ascending air masses is y, and z is the deviation of the temperature profile from a linear scale.

 

3.1 Simulating the Lorenz system using ABM parts

 

To simulate the Lorenz system in PSpice, we rearrange the equations in integral form and introduce initial condition conditions x(t0), y(t0), z(t0) for each system variable. We do this because we will implement these equations using integrators using analog behavioral models (ABM) parts which will be replaced by electronic inverting integrators circuits later. The initial conditions will be dropped for simplicity later but will be included in the simulation model as initial conditions on the integrators. Hence, the first equation, P(y-x), becomes –P(x-y). We could use non-inverting integrators but it’s a little more complicated and left as an exercise to the interested reader. Later, we will see how to use the four-quadrant AD633 multiplier IC to realize the nonlinear product terms. This IC may also be configured to achieve integration using current outputs but that’s much later. The Lorenz equations with initial conditions, t0 are:

 

             Lorenz_oscillator_equation2.png

 

The simplest approach when investigating a chaotic system for the first time is to always use ABM parts, as shown in Figure 1 and later with actual integrated circuit models.  This approach is also useful when the circuit becomes complex and in some cases when the electronic part models cause convergence.

 

                Lorenz_oscillator_figure1.png

 

                                       Figure 1: The Lorenz ABM schematic

 

The ABM INTEG part has its gain set to {–Invert_tau}, where the time constant defined in a PARAM part. The gain of an inverting integrator is set negative and equal to the inverse of the time constant because in the next blog we will use inverting electronic part models. Making the gain as the inverse of the time constant enables us to set a frequency close to the main operating frequency of the system, and in the section on scaling later in this chapter, we will see the need for scaling and how to scale both amplitude and time variables. Figure 2 shows how the three variables vary over time

 

                   Lorenz_oscillator_figure2.png

                        Figure 2: The Lorenz x, y and z output

 

Figure 3 displays the spectra for the variables and is obtained by pressing the FFT icon when in the Probe environment (appears after simulation). Note we may express the spectral components as dB(V(x)*V(x)), to ensure the smaller spectral component are emphasized, otherwise the main spectral component of 1.32 Hz will tend to mask the other components. Select the Add Trace icon (a small graph-like icon), and then select dB( ) from the list of functions in the right panel. Select between the brackets and type v(x)*v(x). However, I just checked before going to press and the dB() function doesn’t now seem to allow the product of variables in the brackets so instead use 10*log10(v(x)*v(x)).  Increasing the simulation run time will increase the frequency resolution but obviously increases the simulation time. The z output is quite periodic and is therefore said to be chaotically weak.

 

                  Lorenz_oscillator_figure3.png

                                                            Figure 3: Power Spectra

 

 

After Probe simulation and to automate the process of placing multiple windows and additional plots, we use the log command which records all keys selected. Select log in Probe File menu. When this is selected, it will record  log file of all keys pressed when doing tasks such as separating the windows. This is useful where you intend to repeat the simulation for parameter variations, for example. If you change the integrator gain from 100 to 1, you will change the system operating frequency hence you will need to change the simulation settings. I have included a log file I created called Lorenz.cmd which will plot all the variables and is called from the File menu in Probe. Select Run Commands and then select Lorenz.cmd. This will plot Figure 1 and 2 but also it will plot the famous Lorenz strange attractor by changing time to the x variable.

Wed, 2020-11-11 04:41
Tue, 2020-12-01 03:53
emaillogininfo
Offline
Last seen: 3 years 4 months ago
Joined: 2020-12-01 03:52

How to sign In SBCGlobal Email Acocunt?

Everything you need to know about your SBCGlobal Email account, SBCGlobal Email Login problems, how to change your password, and more. Also, learn how to update SMTP Imap and POP3 server settings in SBCGlobal Email. You can ask a question in the comment section, and we will aim to resolve your problem in a few days.

SBCGlobal Email Login    
SBCGlobal Login    
SBCGlobal.net Login    
SBCGlobal.net Email Login    

Sat, 2021-10-30 11:55
aisonwrnerxbg
Offline
Last seen: 1 year 11 months ago
Joined: 2021-10-30 11:50

We could use non-inverting

We could use non-inverting integrators but it’s a little more complicated and left as an exercise to the interested reader. |  Residential Painters

Thu, 2022-01-27 06:02
sakshi1234
sakshi1234's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-27 03:59

Article of association

These two fundamental records are MOA and AOA. MOA truly turns Memorandum of Association and the other such record is AOA that tends to Articles of Association. In this, we will look at Articles of Association in short.
The articles of collusion are the affiliation's close by laws, which control its endeavors and working, including the methodology for chiefs, the treatment of cash related records, and different issues. To proceed with this closeness, articles of connection can be viewed as the clients' manual that depicts how the affiliation should work dependably.

Fri, 2022-01-28 08:33
odintfarhat
odintfarhat's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-28 08:27

Bizfile Portal

ACRA BizFile+ Advantages
There are a lot of advantages for organizations to document applications online with BizFile in very little time. A portion of the significant advantages of ACRA's BizFile contain::

Expanded accommodation for organizations
Speedy and financially savvy as there is no administrative work engaged with recording
Improved exactness of information
Further developed consistence in regard of the administrative necessities
Great functional proficiency

Here is <a href="https://ondemandint.com/how-to-fill-up-the-acra-bizfile/"> how to use acra</a> 

Sat, 2022-01-29 05:11
ananduvinayak
Offline
Last seen: 2 years 3 months ago
Joined: 2022-01-29 04:47

dividend


Dividend declarations are the means by which shareholders and investors in companies get returns on their investment. You get dividend distributions only after your companys Board of Directors approves the date when dividends will be distributed. you can read more about “ Reach us ” here

Sat, 2022-01-29 09:09
ananduvinayak
Offline
Last seen: 2 years 3 months ago
Joined: 2022-01-29 04:47

Offshore company

Offshore companies are gaining huge traction these days because of the immense benefits it gives to high-net-worth individuals, companies, and firms. Offshore companies are prominently known to be used for illegitimate uses; it is quite interesting to know that it is purely legal to open an offshore company.

you can read more about “ Reach us” here

Sat, 2022-02-05 03:41
sakshi1234
sakshi1234's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-27 03:59

Benefits of PR for Indians in Singapore

Benefits of PR for Indians in Singapore
To get an unequaled rate, apply for explicit obligations, for instance, contract credits, to buy a property. Singapore PR holders can now purchase state HDB cushions for used plans.
Exploit the money related and responsibility benefits introduced by the Central Provident Fund (CPF) structure in this island country. Under the CPF plan, you and your sidekick contribute a base month to month amount to your retirement store, which can be used for clinical benefits, contract, government retirement accomplice, and flood improvement models.
Following a particular number of years as an incomprehensibly strong inhabitant, you will be ready for full residency, which will permit you an unmistakable proof and deal you comparable possibilities as adjacent tenants.

Wed, 2022-02-16 14:22
odintfarhat
odintfarhat's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-28 08:27

UTR Number

What is perceived by Personal UTRs?
Individual UTRs get given by HMRC consequently for any person who pursues self-evaluation. The individual UTR number can't be utilized for your business UTR number. That will be kept isolated. You will get an alternate UTR number for your firm once it is totally shaped.

It is to be noticed that you don't need to run after the enrollment of the UTR number. HMRC would be educated by the Companies Hose at a particular time, and in a couple of days, you will get a letter at your enrolled office address. This letter will have your UTR number and everything about your expense liabilities.

Wed, 2022-02-16 14:24
odintfarhat
odintfarhat's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-28 08:27

Dormant Company

Importance of a Dormant Company
Lethargic organizations don't effectively take part in exchanging or business exercises and acquire no pay.

The upsides of looking for Dormant status for your organization are that it fixes your expense of organization consolidation and helps in expanding the valuation of your organization - the more it exists, the more its worth.

Lethargic organizations might exist for the accompanying reasons, overall:

  • To hold an organization name
  • To set up a construction for projects later on
  • To adjust the association of your organization
  • To oblige for nonattendance of the entrepreneur
  • To fill in as a holding structure for resources or protected innovation
  • To fill in as a moderate advance before organization disintegration
Fri, 2022-02-25 09:22
sakshi1234
sakshi1234's picture
Offline
Last seen: 2 years 2 months ago
Joined: 2022-01-27 03:59

Joint Stock Company

A Joint Stock Company can raise huge monetary assets in light of its huge number of individuals and it can raise assets through debentures, public stores, credits from monetary organizations absent a lot of trouble.

Tue, 2022-03-22 05:13
priya97
Offline
Last seen: 8 months 4 weeks ago
Joined: 2022-03-22 05:11

Mind blowing

Mind blowing post you have shared for us. I specially congratulate you for this kind of post. Satta Matka

Mon, 2022-04-11 06:29
priya97
Offline
Last seen: 8 months 4 weeks ago
Joined: 2022-03-22 05:11

really helpful

One of the best post I have ever read. I honestly congratulate to you for this post this is really helpful for me. Satta King

Mon, 2022-05-30 00:41
iamaston
Offline
Last seen: 1 year 11 months ago
Joined: 2022-05-30 00:39

Having read this I believed

Having read this I believed it was extremely informative. I appreciate you spending some time and effort to put this informative article together. Safety Signs

Wed, 2022-06-01 01:48
neebwhitlinger25
Offline
Last seen: 1 year 8 months ago
Joined: 2022-06-01 01:42

The Lorenz weather system

The Lorenz weather system models clockwise and anticlockwise thermal convective air mass rotations in a closed container and the ordinary differential equations used in this model were originally created by Barry Saltzman (1962).

 

windshield repair

Fri, 2022-07-01 00:27
iamsrikar
Offline
Last seen: 1 year 10 months ago
Joined: 2022-07-01 00:25

really helpful

I am like to you know that your unique concept really helpful for me and I am surely share this thought to my community. Farm House in Hyderabad

Sun, 2022-07-24 22:32
jully00
Offline
Last seen: 1 year 9 months ago
Joined: 2022-07-24 22:30

much impressive

This is so much impressive. Atleast different from other thought and I am happy for your information. Well do and write more about this topic. Online Matka Play
 

Sun, 2022-07-24 22:32
jully00
Offline
Last seen: 1 year 9 months ago
Joined: 2022-07-24 22:30

much impressive

This is so much impressive. Atleast different from other thought and I am happy for your information. Well do and write more about this topic. Online Matka Play
 

Tue, 2022-08-02 03:08
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Wow, cool post. I'd like to

Wow, cool post. I'd like to write like this too - taking time and real hard work to make a great article... but I put things off too much and never seem to get started. Thanks though. ІНДІЙСЬКА ВІЗА ОНЛАЙН

Sun, 2022-08-07 01:42
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Recently, I have commenced a

Recently, I have commenced a blog the info you give on this site has encouraged and benefited me hugely. Thanks for all of your time & work. Barata Visa Apliko

Mon, 2022-08-08 08:22
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

You there, this is really

You there, this is really good post here. Thanks for taking the time to post such valuable information. Quality content is what always gets the visitors coming. SKUBI KANADOS VIZA

Mon, 2022-08-15 02:17
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Well-Written article. It will

Well-Written article. It will be supportive to anyone who utilizes it, including me. Keep doing what you are doing – can't pause to read more posts. Thanks for the precious help. click here

Sun, 2022-08-21 05:14
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I have recently started a

I have recently started a blog, the info you provide on this site has helped me greatly. Thanks for all of your time & work. Visa medica di l'India

Mon, 2022-08-22 08:24
mtom78632
Offline
Last seen: 5 months 1 day ago
Joined: 2022-01-29 23:04

mtom

It’s nearly impossible to find knowledgeable folks on this topic, but the truth is could be seen as do you know what you are dealing with! Thanks SEO Marketing

Sat, 2022-08-27 03:02
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I felt very happy while

I felt very happy while reading this site. This was really very informative site for me. I really liked it. This was really a cordial post. Thanks a lot!. Tyrkiet visumansøgning online

Mon, 2022-08-29 01:31
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

That is the excellent mindset

That is the excellent mindset, nonetheless is just not help to make every sence whatsoever preaching about that mather. Virtually any method many thanks in addition to i had endeavor to promote your own article in to delicius nevertheless it is apparently a dilemma using your information sites can you please recheck the idea. thanks once more. Best SEO experts

Sat, 2022-09-03 06:38
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I am happy to find this post

I am happy to find this post Very useful for me, as it contains lot of information. I Always prefer to read The Quality and glad I found this thing in you post. Thanks VISA DARURAT KANADA

Wed, 2022-09-07 06:51
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

This is very educational

This is very educational content and written well for a change. It's nice to see that some people still understand how to write a quality post.! Application ng Indian Visa

Tue, 2022-09-13 08:09
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Remarkable article, it is

Remarkable article, it is particularly useful! I quietly began in this, and I'm becoming more acquainted with it better! Delights, keep doing more and extra impressive! เว็บไซต์ทางการของวีซ่าแคนาดา

Thu, 2022-09-15 02:47
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

You’ve got some interesting

You’ve got some interesting points in this article. I would have never considered any of these if I didn’t come across this. Thanks!. BRITISH COLUMBIA FAKE DRIVING LICENCE

Sat, 2022-09-17 01:57
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Superbly written article, if

Superbly written article, if only all bloggers offered the same content as you, the internet would be a far better place.. Prijava za indijsku vizu

Sat, 2022-09-24 02:53
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I really thank you for the

I really thank you for the valuable info on this great subject and look forward to more great posts. Thanks a lot for enjoying this beauty article with me. I am appreciating it very much! Looking forward to another great article. Good luck to the author! All the best! new zealand tourist visa

Thu, 2022-09-29 02:17
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Its a great pleasure reading

Its a great pleasure reading your post.Its full of information I am looking for and I love to post a comment that "The content of your post is awesome" Great work. ویزای ورودی نیوزلند به صورت آنلاین

Sun, 2022-10-16 02:54
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Wow, What an Outstanding post

Wow, What an Outstanding post. I found this too much informatics. It is what I was seeking for. I would like to recommend you that please keep sharing such type of info.If possible, Thanks. situs slot

Tue, 2022-10-18 08:27
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

If you are looking for more

If you are looking for more information about flat rate locksmith Las Vegas check that right away. Visa du lịch Thổ Nhĩ Kỳ

Sun, 2022-10-23 01:26
ioshelby
Offline
Last seen: 1 year 6 months ago
Joined: 2022-10-19 10:09

that right away https://www

that right away https://www-staging.overdrive.com/

Sun, 2022-10-23 01:27
ioshelby
Offline
Last seen: 1 year 6 months ago
Joined: 2022-10-19 10:09

Las Vegas check http://ttps:/

Las Vegas check http://ttps://aics-ehs.asus.com/

Sun, 2022-10-23 01:28
ioshelby
Offline
Last seen: 1 year 6 months ago
Joined: 2022-10-19 10:09

for more information https:/

for more information https://miners.minerba.esdm.go.id/js/slot-hoki/

Sun, 2022-10-23 01:28
ioshelby
Offline
Last seen: 1 year 6 months ago
Joined: 2022-10-19 10:09

you are looking for more

you are looking for more information about flat rate locksmith Las Vegas https://mydatauis.athenahealth.com/

Sun, 2022-10-23 06:03
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Thank you for some other

Thank you for some other informative blog. Where else could I get that type of information written in such an ideal means? I have a mission that I’m just now working on, and I have been at the look out for such information. Ernährungsberatung für Kinder

Wed, 2022-10-26 08:52
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

This content is written very

This content is written very well. Your use of formatting when making your points makes your observations very clear and easy to understand. Thank you. Canada visumansøgning online

Sun, 2022-10-30 17:26
jhon set
Offline
Last seen: 2 days 3 hours ago
Joined: 2022-09-12 11:46

Go Right Here

choosing one of the court cards and write a story about it, using your imagination, just for fun. You can meditate with your cards, or paint a picture of a chosen card, compose music to one. Go with your inspiration and enjoy yourself, consider it playtime! tarot what he feels for you

Wed, 2022-11-02 07:17
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Thanks for taking the time to

Thanks for taking the time to discuss this, I feel strongly about it and love learning more on this topic. If possible, as you gain expertise, would you mind updating your blog with extra information? It is extremely helpful for me. 在线加拿大签证申请表

Sat, 2022-11-05 06:29
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

This is highly informatics,

This is highly informatics, crisp and clear. I think that everything has been described in systematic manner so that reader could get maximum information and learn many things. CANADA VISA HELP DESK

Tue, 2022-11-15 05:59
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

That is the excellent mindset

That is the excellent mindset, nonetheless is just not help to make every sence whatsoever preaching about that mather. Virtually any method many thanks in addition to i had endeavor to promote your own article in to delicius nevertheless it is apparently a dilemma using your information sites can you please recheck the idea. thanks once more. Solicitud en línea de visa de Canadá

Sat, 2022-11-19 00:27
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

It is an excellent blog, I

It is an excellent blog, I have ever seen. I found all the material on this blog utmost unique and well written. And, I have decided to visit it again and again. ZAHTJEVA ZA VIZU ZA NOVI ZELAND

Mon, 2022-11-21 01:39
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

It is a fantastic post –

It is a fantastic post – immense clear and easy to understand. I am also holding out for the sharks too that made me laugh. בארעכטיגונג פון קאַנאַדע וויזע

Wed, 2022-11-23 01:43
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I’m going to read this. I’ll

I’m going to read this. I’ll be sure to come back. thanks for sharing. and also This article gives the light in which we can observe the reality. this is very nice one and gives indepth information. thanks for this nice article... 加拿大医疗签证

Fri, 2022-11-25 05:46
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

I'm glad to see the great

I'm glad to see the great detail here!. VIŻA INDJAN TA’ EMERĠENZA

Sun, 2022-11-27 05:55
basit khatri66
basit khatri66's picture
Offline
Last seen: 3 hours 56 min ago
Joined: 2022-06-28 05:48

Thanks for your insight for

Thanks for your insight for your fantastic posting. I’m glad I have taken the time to see this. ABD Vize Başvurusu

Download PSpice and try it for free! Download Free Trial
Cadence