Maplesoft Blog

The Maplesoft blog contains posts coming from the heart of Maplesoft. Find out what is coming next in the world of Maple, and get the best tips and tricks from the Maple experts.

A wealth of knowledge is on display in MaplePrimes as our contributors share their expertise and step up to answer others’ queries. This post picks out one such response and further elucidates the answers to the posted question. I hope these explanations appeal to those of our readers who might not be familiar with the techniques embedded in the original responses.

Before I begin, a quick note that the content below was primarily created by one of our summer interns, Pia, with guidance and advice from me.

The Question: Source Code of Math Apps

Eberch, a new Maple user, was interested in learning how to build his own Math Apps by looking at the source code of some of the already existing Math Apps that Maple offers.

Acer helpfully suggested that he look into the Startup Code of a Math App, in order to see definitions of procedures, modules, etc. He also recommended Eberch take a look at the “action code” that most of the Math Apps have which consist of function calls to procedures or modules defined in the Startup Code. The Startup Code can be accessed from the Edit menu. The function calls can be seen by right-clicking on the relevant component and selecting Edit Click Action.

Acer’s answer is correct and helpful. But for those just learning Maple, I wanted to provide some additional explanation.

Let’s talk more about building your own Math Apps

Building your own Math Apps can seem like something that involves complicated code and rare commands, but Daniel Skoog perfectly portrays an easy and straightforward method to do this in his latest webinar. He provides a clear definition of a Math App, a step-by-step approach to creating a Math App using the explore and quiz commands, and ways to share your applications with the Maple community. It is highly recommended that you watch the entire webinar if you would like to learn more about the core concepts of working with Maple, but you can find the Math App information starting at the 33:00 mark.

I hope that you find this useful. If there is a particular question on MaplePrimes that you would like further explained, please let me know. 

A wealth of knowledge is on display in MaplePrimes as our contributors share their expertise and step up to answer others’ queries. This post picks out one such response and further elucidates the answers to the posted question. I hope these explanations appeal to those of our readers who might not be familiar with the techniques embedded in the original responses.

Before I begin, a quick note that the content below was primarily created by one of our summer interns, Pia, with guidance and advice from me.

MaplePrimes member Thomas Dean wanted 1/2*x^(1/2) + 1/13*x^(1/3) + 1/26*x^(45/37)  to become  0.5*x^0.500000 + 0.07692307692*x^0.333333 + 0.03846153846*x^1.216216216  using the evalf command.

Here you can see the piece of code that Thomas Dean wrote in Maple:

eq:=1/2*x^(1/2) + 1/13*x^(1/3) + 1/26*x^(45/37);

Carl Love replied simply and effectively with a piece of code, using the evalindets command instead:

evalindets(eq, fraction, evalf);

As always, Love provided an accurate response, and it is absolutely correct. But for those just learning Maple, I wanted to provide some additional explanation.

The evalindets command, evalindets( expr, atype, transformer, rest ), is a particular combination of calls to eval and indets that allows you to efficiently transform all subexpressions of a given type by some algorithm. It encapsulates a common "pattern" used in expression manipulation and transformation.

Each subexpression of type atype is transformed by the supplied transformer procedure. Then, each subexpression is replaced in the original expression, using eval, with the corresponding transformed expression.


Note: the parameter restis an optional expression sequence of extra arguments to be passed to transformer. In this example it was not used.

I hope that you find this useful. If there is a particular question on MaplePrimes that you would like further explained, please let me know. 

Here are some tips and tricks - ranging from keyboard shortcuts to the newest features - that will help you get the most out of MapleSim 2015.

  1. Quickly run your simulation by pressing F5. Similarly, toggle between the Main Window and Visualization Window by press F6.

  2. Maintaining an organized and clean model layout is made easier by using the Reroute Connections tool. Select the connection lines or components and press CTRL+D (or using the Edit menu, Reroute Connections) to have MapleSim automatically reroute the connections.

  3. While creating your MapleSim model, components and connections can be enabled or disabled by selecting the desired item(s) and using the disable/enable button (  ) or the keyboard shortcut CTRL+E.

  4. Use the Model Tree palette in MapleSim to help manage, navigate, and search a model quickly. Items within the model tree include: components, probes, parameters, and attachments. Simply select the desired view using the drop-down menu. The Model Tree palette is found under the Project tab.

  5. Automatically remove any unreferenced subsystems or custom components using the Prune Model tool. Especially useful for large models or models with multiple modifications, this tool will automatically identify and removes unused shared subsystems or custom components that appear within the Definitions tab, Components palette. The Prune Model function can be performed by clicking the Edit menu, and selecting Prune Model.

  6. Set the MapleSim’s Visualization Window to always on top by toggling the anchor button (  ) in the upper left corner of the Visualization Window.

  7. Automatically scale the model diagram to fit in the viewable area by pressing CTRL+T to gain a complete look at the model. Then return to a default zoom by pressing CTRL+0 (zero). This is also accessible using the View menu.

  8. To group components into a subsystem, select the desired components, right-click and select Create Subsystem or press CTRL+G.

  9. For quick access to get help on a particular component, right-click on it and select help. Similarly, selecting a component within the workspace and pressing F2 will bring up the help page for that component.

  10. View the Modelica code behind the visible system/subsystem/component, click Code View (  ) in the Navigation Tool bar. Then, to switch back to Diagram Mode click the icon (  ) in the Navigation Tool bar.

  11. Automatically compare two models by using the compare tool, found under the Tools menu Compare Models.

  12. Attach important files to a MapleSim model to keep content in one place. Attachments can be Maple worksheets or others such as pdfs, Excel, Word, STL files, etc. These files are found under the Project Tab, Attachments palette. Attach a file by, right-clicking the category and selecting Attach File or clicking the Edit menu Attach File.

I hope you find these useful! Do you have any tips that you would add to this list?

The first instalment in the Hollywood Math webinar series will be returning live this September 17th! It will be presented by Daniel Skoog, our Maple Product Manager.

Over its storied and intriguing history, Hollywood has entertained us with many mathematical moments in film. John Nash in “A Beautiful Mind,” the brilliant janitor in “Good Will Hunting,” the number theory genius in “Pi,” and even Abbott and Costello are just a few of the Hollywood “mathematicians” that come to mind.

During this webinar we will present a number of examples of mathematics in film, including those done capably, as well as questionable and downright “creative” treatments. See relevant, exciting examples that you can use to engage your students, or attend this webinar simply for its entertainment value. Have you ever wondered if the bus could really have jumped the gap in “Speed?” We’ve got the answer! Anyone with an interest in mathematics, especially high school and early college math educators, will be both entertained and informed by attending this webinar.

To join us for the live presentation, click here to register.

A wealth of knowledge is on display in MaplePrimes as our contributors share their expertise and step up to answer others’ queries. This post picks out one such response and further elucidates the answers to the posted question. I hope these explanations appeal to those of our readers who might not be familiar with the techniques embedded in the original responses.

Before I begin, a quick note that the content below was primarily created by one of our summer interns, Pia, with guidance and advice from me.

The Question: why is 2*cos(x)^2-1 simpler than 1-2*sin(x)^2

The author, nm, asked why 2*cos(x)^2-1  was simpler than 1-2*sin(x)^2 according to Maple. nm wrote:

I looked at help trying to understand why Maple thinks 2*cos(x)^2-1 is simpler than 1-2*sin(x)^2 but did not see it. I was expecting to see cos(2*x) as a result.

Preben Alsholm answered nm’s question by recommending the use of the combine command to obtain the result he was expecting to see, as well as a further explanation on how the simplify command works. Alsholm wrote:

Use combine to obtain what you want:

simplify has a general preference for cos over sin. That doesn't mean however, that it turns sin into cos at all costs:

##Try also

simplify doesn't necessarily get you the simplest result in the common sense of the word 'simplify'. Try as another example


As always, Alsholm provided an accurate, thoughtful response. But for those just learning Maple, I thought some additional explanation could be helpful.

Let’s talk more about the simplify command and combine function

The simplify command applies simplification rules to an expression. Its parameters can be any expression.

The combine function applies transformations which combine terms in sums, products, and powers into a single term. For many functions, the transformations applied by combine are the inverse of the transformations that are applied by expand. For example, consider the well-known identity:

sin(a + b) = sin(a) cos(b) + cos(a) sin(b)

The combine function applies the identity from right to left, whereas the expand function does the reverse.


I hope that you find this useful. If there is a particular question on MaplePrimes that you would like further explained, please feel free to contact me.


My desk was covered with papers, a glass of water, and a big shipping container. Even though my chair was there, I was sitting on the floor with my laptop, having a bad hair day, and a robot was seated next to me.  This was a typical day at Maplesoft for an engineering co-op student.

For this project, at the request of my manager, I left my duties as Spanish translator and marketing assistant and I started to work with the robot NAO from Aldebaran Robotics. The purpose of this project was to program NAO using Aldebaran’s Choreographe software to make new movements and dances that I would later use to create new MapleSim models for Maplesoft’s Model Gallery. Maplesoft’s marketing team would then use these models in some of their promotional activities.

Given that NAO was going to travel to Taiwan in a short period of time, I wanted to focus on doing one elaborate dance and a couple of simple movements.Thanks to F.U.N. lab from the University of Notre Dame, I was able to focus on the detailed dance because they had an amazing Choreographe database of behaviour/movement code.   

I started this project with zero knowledge about Choreographe, but with a good understanding of NAO´s MapleSim model that the Maplesoft engineers had previously created. After a few weeks with NAO and some YouTube tutorials, I discovered that programming NAO was really easy. I would move NAO’s joints to the positions I wanted to, and then I would tap its head to record and save them. I did this for a couple of weeks making sure that the sequence of movements wouldn’t make NAO fall or break a finger. At this point I was already a NAO expert.

After finishing up all the movements and dances it was time to move on to the next phase of the project: obtaining the data for the MapleSim model. The MapleSim model was created using the Denavit-Hartenberg (DH) convention; therefore, I needed the values of the degrees of rotation of each joint while the robot performed a dance. These numbers were easily obtained using the “record” button in Choreographe and exporting them into a CSV file. This file was later attached to the MapleSim model, so it could be used in a time look up table. The input of NAO´s joints were then specified by using the values within this table.

I started by recording the simplest movements: NAO blowing kisses and doing the sprinkler. These were the best ones to start working on because in these examples, the robot only needs to move its upper body, meaning that the lower body didn’t need any flexibility. This gave me and Abtin Athari, Application Engineer at Maplesoft, the freedom to simplify the original model by removing unnecessary degrees of freedom on the lower body. Abtin and I also realized that at the beginning of some of the new movements the robot would have too much torque, so we extended some of the recorded position of the rotational joints so the robot could stay in the same position for a longer time. These modifications ensured that the model wouldn´t have any problems during any of the simulations.

To finish the project, I worked with the Marketing team to create some videos where we could display the real robot next to the MapleSim model doing the same movements. The purpose of these videos was to showcase the essence of the high-fidelity models that MapleSim allowed us to create. It was amazing to see how the MapleSim model corresponded so closely to the physical robot.

After three weeks of intense work and meetings, my days as a robot whisperer ended. I learned new things about robots, how to build models with MapleSim, and the processes behind developing videos. It was a project that allowed me to wear both an engineer’s and a marketer’s shoes.  I was able to put into practice my technical knowledge and problem solving skills; and at the same time I was able to enhance my creative and analytical skills by evaluating the quality and impact of my work.

Philip Yasskin, a long-time Maple user and professor at Texas A&M University is passionate about getting young people engaged in mathematics. One of his programs is SEE-Math: a two-week summer day camp for gifted middle school children interested in math. Maplesoft has been a long-standing supporter of SEE-Math, providing software and prizes for the campers.

A major project in SEE-Math is developing computer animations using Maple. Students spend their time creating various animations, in hopes of taking the top prize at the end of the workshop. A slew of animations are submitted, some with pop-culture references, elaborate plot lines, and incredible detail. The top animations take home prizes, while all animations from that year are featured on the SEE-Math website.

Maplesoft proudly sponsors this event, and many like it, to promote interest in STEM education. To see all of the animations from this year’s SEE-Math camp, please visit: You can find the animations listed under “Euler,” “Godel,” “Noether,” and “Ramanujan,” found halfway down the page.

In addition to providing access to powerful tools for mathematical computation, Maple has been designed to help you work quickly and efficiently. Here are 10 useful short-cuts when working with Maple:

1. Use F5 to switch between Text and 2D Math input modes in Maple.

2. Use F2 (Control+? for Macintosh) to quickly bring up Maple Help information for anything that you have typed in your document.

3.  Automatic Command Completion can be used when you don't want to type in the full name of a Maple command. To use, begin typing the first few letters of the command name, and press CTRL+Space (Esc or Command+Shift+Space for Macintosh, CTRL+Shift+Space for Linux).  A list of possible completions will display; click the one you want.


4. The Shift+Enter key combination lets you continue entering math or commands on a new line without executing that line. 

5. If you want more than a single command to be executed at once, you must separate them with a semi-colon or colon.

6. When you click inside a set of commands in Math mode, the dash line indicates the boundaries of the input region; all commands in this region will execute together in sequence.

7. To increase the size of a piecewise function, add a new row.  Place the cursor on the last row, and press CTRL+Shift+R (Command+Shift+R for Macintosh). These shortcut keys also work to add rows to matrices.

8. An easy way to insert a Greek letter is to first press CTRL+Shift+G (Command+Shift+G for the Macintosh). The next letter typed will appear in Greek.

9. Sometimes you may want to insert symbols above or below another character, for example, to enter a vector arrow. To insert a symbol above (called "overscript"), press CTRL+Shift+["] (Command+Shift+["] for Macintosh) and then type in your symbol (or insert it from a palette).

For example, typing "x" then holding down CTRL+Shift and pressing ["] allows you to insert a symbol above the x, such as 

10. Compute or recompute the entire Maple worksheet when you have changed expressions that affect subsequent Maple commands.  Press Ctrl + Shift + Enter (Command + Shift + Enter in Macintosh) or click the execute worksheet icon. 

Are there any short-cuts that you would add to this list?

As an educator, you surely know that giving students more involved problems in an online assessment tool provides challenges, both for students and instructors. Only marking the final answer doesn’t necessarily provide an understanding of the student’s capabilities, and it penalizes students that make a small mistake in part of their solution.

This webinar will demonstrate how to create separate questions with multiple steps that can be linked or chained together. Question chaining allows instructors to mark subsequent questions based on the correct answer or the answer provided by students in previous parts.

To join us for the live presentation, please click here to register.

Here are some tips and tricks that will help you get the most out of Maple 2015, covering from short cuts to how to use the newest features.

    1. Whenever you are asking yourself “..but how do I do it?”, just type ?Portal+Enter, and you will access the Maple Portal, which will give you a complete guide on how to do things.

    2. If you want to implement 1 of the 300 tasks that Maple offers in a syntax-free way, like Completing the Square, just follow this path: Tools≻Tasks≻Browse.

    3. Type Ctrl+F2 or Command+F2 and the Quick Reference window with shortcut keys and other information about working with the Maple interface will pop up.

    4. If you need quick help with a specific mathematical function, click or highlight the function + F2 and a Help box that contains a summary of the basic characteristics of the function will pop up.

    5. If you have installed the Excel Add-in and you want to perform some Maple commands within Excel, make sure to enable the Maple add in by following this path: Excel’s Tool Menu>Add-Ins>Select Maple Excel Add-in Box> OK

    6. Export Maple’s data into Excel by right clicking and choosing ‘Export As’>Excel.

    7. Instead of having to copy-paste your Maple information into a Power Point Presentation, just turn the slideshow mode on by pressing F11. This way you will have an interactive presentation that holds all the live plots and embedded components that Maple offers.

    8. Whenever you want to create interactive mini-applications that can be used to explore the parameters of any arbitrary Maple expression, such as a plot, mathematical equation, or command use the Exploration Assistant. Do this by either right-clicking +Explore from the context-sensitive menus, or by calling the Explore command.

    9. Save time while computing mathematical expressions by calling the equation label instead of having to re-type the equation. Do this by pressing CTRL+L and then input the number that identifies the equation.

    10. Reference mathematical equations or expressions from other documents. First, determine which label is associated with the equation you want. In the main document, select "Insert" > "Reference". From the file dialog, select the file containing the expression. Then select the equation reference number of your equation from the list that appears.

    11. In Maple, the letter "e" entered using the keyboard does not represent the exponential function. The exponential function can be entered using command completion (Ctrl+Space or ESC) or the "exp(a)" item in the Expression Palette (Standard interface only). The exponential can also be entered as:          
      > exp(x)

    12. With Maple 2015 you can now access data sets from various built-in and online data sources. This package is able to access time series data from the data aggregator Quandl, as well as locally installed data from countries and cities. To learn more, click here.

    13. Whenever you assign plots to a variable name, p:=[plot(sin(x)), plot(cos(x))] a thumbnail of the plot will appear instead of the code.

    14. Save time when inputting existing or personalized units. Just click CTRL+SHIFT+U and type the desired units you want.

    15. With Maple 2015 you can now zoom in or out just by pressing CTRL+SCROLL or CTRL+ place two fingers on the pad and move them up to zoom in or down to zoom out.

    16. Convert a Maple Worksheet into Microsoft Word: This can be done using the Export to HTML feature.
      1. Prepare your worksheet as you would like it to appear in the document.
      2. From the "File" menu in Maple, select "Export As ..." > "HTML".
      3. Give the HTML file a name, "output.html" for example.
      4. When the export has completed, start Word, and open the HTML file. If you used "output.html" as the name to save the file as, open the file called "output1.html" into Word.
      5. From the "File" menu in Word, select "Save as Word Document" to save the file. You now have a Word document which contains the content of your Maple worksheet.

        Note: this procedure will work with any Word Processing program that can open an HTML document.

    17. Change Maple’s default input from 2D to 1D:
      1. Open the Tools > Options... menu (Maple > Preferences on a MACINTOSH machine).
      2. Select the Display tab
      3. From "Input Display" menu select Maple Notation
      4. Press the Apply to Session button to make the change take effect for the current Maple session.
      5. Press Apply Globally to have the change take effect permanently. Maple will need to be restarted if you choose Apply Globally for the changes to take effect.

        You may download a set of instruction on how to change your 2D interface to the “Classic” Style here:

We hope that you find this list helpful. Please feel free to add any of your tips or techniques to this post, or to create your own new topic.

Last month, we received a very kind note from a recipient of one of our sponsorships. Maplesoft sponsors several academic and commercial events throughout the year, providing free copies of Maple or MapleSim to lucky attendees. Audrey was one of the winners of the Elgin Community College Calculus Contest, where she won a copy of Maple. Here’s what she had to say:

Thank you so much for the Maple license.  I have become familiar with Maple during the last school year.  At first the commands were like Chinese to me and I had a rough time getting anything done, but once I made a connection between the commands and what they were doing it was a lot easier.  Even without former knowledge of computer programing, the commands are increasingly intuitive.  Maple has been a huge help to me doing my homework and projects, and even as I was studying for the competition it was useful for checking my answers.  Another reason that I love Maple is that it provides visuals for the difficult concepts we learned in class, such as shell method in Calc II and mixed partial derivatives in Calc III.  I enjoy math, but I thank that Maple has enriched my experience along the way.

Thank you again for your generous gift, 


It’s always nice to hear how students and professionals alike are succeeding with the help of Maple. If you’d like to share your experience, please send an email to or post it here on MaplePrimes.

You are teaching linear algebra, or perhaps a differential equations course that contains a unit on first-order linear systems. You need to get across the notion of the eigenpair of a matrix, that is, eigenvalues and eigenvectors, what they mean, how are they found, for what are they useful.

Of course, Maple's Context Menu can, with a click or two of the mouse, return both eigenvalues and eigenvectors. But that does not satisfy the needs of the student: an answer has been given but nothing has been learned. So, of what use is Maple in this pedagogical task? How can Maple enhance the lessons devoted to finding and using eigenpairs of a matrix?

In this webinar I am going to demonstrate how Maple can be used to get across the concept of the eigenpair, to show its meaning, to relate this concept to the by-hand algorithms taught in textbooks.

Ah, but it's not enough just to do the calculations - they also have to be easy to implement so that the implementation does not cloud the pedagogic goal. So, an essential element of this webinar will be its Clickable format, free of the encumbrance of commands and their related syntax. I'll use a syntax-free paradigm to keep the technology as simple as possible while achieving the didactic goal.

Notes added on July 7, 2015:

We’re trying out something new with our webinars and are hosting our first ever live streaming webinar. Broadcast in real time, and featuring Jonny Zivku, our Maple T.A. Product Manager, this will be your chance to see the face behind the voice, as well as learn more about how academic institutions around the world are using Maple T.A. We hope you can join us.

Here are the full details:

Transforming Testing and Assessment with Maple T.A.

In this webinar, you will learn how Maplesoft's testing and assessment system, Maple T.A., is being used to improve learning, save money, reduce drop-out rates, and increase student satisfaction at academic institutions around the world.

The following Maple T.A. case studies will be presented:

  • The University of Waterloo saved $100,000/year on their grading budget
  • At the Amsterdam University of Applied Science, student pass rates went up approximately 20% within one year
  • The University of Canterbury continued to offer their full academic program after an earthquake damaged classrooms
  • At the University of Guelph, drop-out rates were reduced by more than 10%
  • ...And more!

All attendees of this webinar will be sent a complimentary copy of the Maplesoft magazine Transforming Testing and Assessment.

To join us for the live streaming webinar, please click here to register.

The trailers for the new Star Wars movie (Star Wars: The Force Awakens) introduced a new Droid called BB-8. This curious little guy features a spherical body and a controlled instrumented head. More recently, the BB-8 droid was showcased in a Star Wars celebration event and to many peoples' surprise it is real and not a CGI effect!

We have a Sphero robot from Orbotix here at the office, and there was an immediate connection between BB-8 and the Sphero. All that remains is to add the head!

Many have already put together their version of the BB-8, but I wanted to have a physical model that I can play with in a virtual environment and explore some design options.



To build a model of BB-8 like robotic system in MapleSim (Maplesoft's physical modeling software environment), I first needed a couple things in place before going forward:

  1. A few simple CAD shapes (half-sphere, wheels)

  2. A component to represent the contact between two spheres (both outside contact and inside contact)

I used Maple’s plottools package to build the CAD files I needed. First a half-spherical shape:

Then a wheel:


The next step was to create the contact component in MapleSim. I used a Modelica custom component to bring together vector calculations of normal and tangential forces with a variety of options for convenience into one component:



Build the model:

We start with a spherical shape contacting the ground:


Then we add two wheels inside it, and a hanging mass to keep the reference axis vertical when the wheels turn:


Learning from published diagrams showing the internal mechanism of a Sphero, another set of free wheels improves the overall stability when motion commands are given to the two active wheels:


Now this model can be used to move around the surface by giving speed commands to the individual motors that drive to the two bottom wheels. What is needed next is the head and the mechanism to move it around.

Since the head can move almost freely, independent of body rotation, it has to be controlled via magnetic contacts and a controlled arm.

First, we add the control arm:


Now we need to build the head.

The head has an identical triangle to the one at the end of the control arm. At each vertex there is a ball bearing that would slide on the surface of the main spherical body without friction. The magnetic force between the corresponding vertices of the two triangles is modeled via the available point-to-point force element in MapleSim.



Once assembled, the MapleSim model diagram looks like this:


...and our BB-8 droid looks like this:



Seeing the BB-8 in action:

Now that we have constructed our droid in MapleSim, we can animate and see it in action!


Maplesoft regularly hosts live webinars on a variety of topics. Below you will find details on upcoming webinars we think may be of interest to the MaplePrimes community.  For the complete list of upcoming webinars, visit our website.

Case Study: Transforming a University's Placement Testing Process

This webinar will feature the story of how the University of the Virgin Islands moved their placing testing process from paper and pen to using the Mathematical Association of America’s (MAA) placement tests offered through the Maple T.A. testing environment. Instructors at the university now handpick questions to create their own placement tests that best fit the course they are teaching. From there, they are able to analyze the data and craft lessons based on student performance. The end result is that students are more satisfied with the education they are receiving and instructors have made enormous gains with regards to efficiency and flexibility.

To join us for the live presentation with Dr. Celil Ekici from the University of the Virgin Islands, please click here to register.

Getting Started with Maple

This webinar is designed for the user who comes to Maple for the first time. It will demonstrate “how to get started” by clarifying the user interface and the ways math can be entered into Maple, and then “processed.” Coverage includes

  • Entering mathematical expressions and interacting with them in a syntax-free way.
  • The difference between input in mathematical notation and “linear” or text form.
  • The role of the Context Sensitive Menu system for interacting with mathematical objects.
  • Graphing and interacting with various types of graphs, including animations, surfaces, and implicit plots.
  • Use of built-in tools such as Assistants, Tutors, and Task Templates.
  • The Maple help system and the Maple Portal.
  • Introduction to differential equations and matrix manipulations.

To join us for the live presentation, please click here to register.

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