Educational Wind Turbine: Fall 2021 Update

During the Fall 2021 semester, much of the construction of the wind turbine was completed. This includes the the base, tower, and nacelle with generator, blades, and tail. The
Added by ESW Akron OH about 1 month ago

Progress made during Fall 2021:

  • Turbine blades purchased and acquired.
  • Wind turbine base materials purchased and assembled.
    • The base is made from plywood with 2x4's for reinforcement.
    • Two elbows and a T-fitting are used to attach tower to the base.
  • Tower assembled.
    • Donated piping was used for the tower
  • Nacelle constructed with blades, generator, and tail.
    • Blades were attached to hub of the generator.
    • Generator was attached to nacelle through multiple pipe clamps.
    • Tail was fabricated using donated car fenders.
  • The electrical system was completed.
    • This consisted of connecting the generator to the battery with a diode in line.

In the Spring 2022 semester, the Wind Turbine Team plans to:

  • Reinforce the way the current nacelle is fixed to tower.
    • Current system is weak and susceptible to fatigue.
  • Add stability to tower through the use of guy-lines.
    • Current tower is secured by rigidly fixing base.
  • Test power output during operation.
    • The wind turbine will be assembled in open field on windy day.

A big thanks to the graduating seniors for all the work they have put into this project!

First raising of the wind turbine.

Construction of the nacelle.

Completed base with wiring being fed through tower to be connected to generator.


NU - AutoAquaponics: Fall 2021 Update

AutoAquaponics Progress From Fall of 2021
Added by ESW NU about 1 month ago

AutoAquaponics kicked off the year with a strong start and greatly expanded the number of first and second year students on our team. This quarter we welcomed Spencer Huie, Lester Tai, Yanni Wilcox, Ian Viegas, Vianey Guadian, Anabel Sanchez, Ellie Lind, and Ally Lazar to the team, and we were finally able to have in-person meetings for the first time. We were also recognized in a variety of Northwestern press such as the NU Declassified: Exploring Engineering podcast, The Daily Northwestern's article on climate advocates on campus, and the official McCormick School of Engineering Fall 2021 Magazine for the unique projects and welcoming communities we created. As a result of increasing membership and the solid foundation established by our existing member's research and design, AutoAquaponics was able to achieve the following in each of the sub-teams:


  • Reattached a glass panel to the fish tank and successfully water testing the tank (it holds water with no leak!!!)

  • Completed a secondary containment berm around the entire aquaponic system with a combination of laser-cut clips, waterproof tarp, 3D printed brackets, and leftover plywood to prevent minor spills from reaching the carpet

*Big thanks to SmartTree members for helping us clear the room so we can slide the containment berm under both of our shelves!

  • Plumbed the grow beds and the fish tank together with PVC pipes and bulkheads

  • Redesigned the water filtration system to decrease the flow rate to the settling tank to boost efficiency

  • Designed a color scheme to paint the grow bed and fish tank (stay tuned for next quarter's blog to see what it looks like :D )


  • Resolved the common issue of TDS sensors shorting pH ion selective electrodes and affecting each other's values

  • Created a concept and began 3D printing parts for a 2-motor design for the automatic water tester

  • Generated part of the CAD for a new outlet box enclosure that will allow for energy monitoring and a switch to enable "programming" mode for the ESP32
  • Tested mixing mechanism with magnetic stirrers for the automatic water tester reagents
  • Debugged automatic fish feeder stepper motor issues


  • Resolved GUI crashing issue and memory build-up from matplotlib
  • Reduced system lag by decreasing plotting frequency
  • Created a branch of the main repository to experiment with using blitting to speed up plotting speed
  • Train new members on Python programming, specifically how to use TKinter to create graphical user interface

The system design went through quite a few changes due to our recent discovery that indexing valves do not work as well as we thought (special shoutout to Kaitlyn Hung for leading the team on troubleshooting the valve and communicating with the manufacturer!), so we will instead be using two solenoids to control which grow bed gets water. Luckily, our electronics team was able to make the necessary (although slightly painful) adjustments to accommodate for the additional actuators we need to control. Next quarter, the team will aim to completely finish the outlet box (software and hardware portions), solenoid installation, and water filtration system so we can do a trial run of everything before Spring Break.

Photo of a now in-person AutoAquaponics whole-team meeting:

ESWNU team photo (includes our friends from SmartTree and the ESWNU exec board!):

Fun picture - the new official AutoAquaponics logo (designed by Sandra Chiu) on vinyl stickers that our members can use to show off their ESW pride:

Thank you for your support, and keep an eye out for more from AutoAquaponics in the Winter!

NU - SmartTree: Fall 2021 Update

Added by Katie Lev about 1 month ago

SmartTree has made great progress this quarter! After a very successful spring/summer, Project Managers Callista and Katie hoped to continue this momentum by bringing in new members, finalizing project details and starting construction. SmartTree is extremely excited to share that we have done it all!

We brought in multiple new members of backgrounds to aid progress on accomplishing all the tasks we had planned over the summer. Here’s a picture we took with most of our active members!

Although former experiences varied, all the SmartTree members were eager to join design conversations while we were finalizing the SmartTree design and learn new things outside of their comfort zone. We even had a group of three students, two of which with no prior experience, create an electrical team to focus on building the very core of our structure, which will help convert the solar energy harnessed into usable power! Cally and Katie really enjoyed watching this group grow in confidence and knowledge over the quarter.

Beyond electrical, SmartTree also had a construction team that met for around 4 hours/week in the Ford Design Shop to build our structure. We learned how to be safe in the shop around the heavy machinery, how to use various machines and power tools, as well as and how important tolerancing is. At this point, we have a significant portion of our giant modular base pieces cut out with most of our materials delivered to our office.

Mostly we focused on the outer base pieces. First, we cut out the exterior portions using a panel saw. Then, we drew and cut out the geometries on the bottom using a band saw. These angles are cut out so these pieces fit snug on the triangular foundation. We also started mitering these pieces so they fit together smoothly at the proper angle of 60 degrees. We'll definitely be continuing to miter throughout the winter as it's a lengthy and time-consuming process. ![](side piece.jpg)

For the interior portions, we followed the same procedure of cutting with a panel saw then tracing the complex geometries and cutting them out with the band saw. We are still in the middle of tracing and cutting with the band saw and plan to continue this process throughout the winter. The unique part of the interior portion is the gaping hole used for access to electrical wiring. We will be cutting these out with a handheld table saw during the winter. ![](mid piece.jpg)

With that being said, we’ve also finalized plans, ordered materials, prepared parts and are so excited to continue on in the winter! Hope everyone has an amazing rest of their 2021, and we will touch base once again at the end of the upcoming quarter with even more updates on our structure!

Texas A&M Greenhouse Air Analyzer: Winter 2021 Update

Added by Jenny Vu about 1 month ago

We have now accomplished our goal of installing a remote monitoring system at the greenhouses on campus! In August 2020, ESW’s Texas A&M University chapter set out to design and implement a remote monitoring system for the environments of the Greenhouses on campus. It is now December 2021 and in that time we have had a few setbacks and course corrections but also many accomplishments and now at last a working solution.

During this fall semester, we welcomed two new members to the team, Chloe and Zahra. Throughout the whole project, our team consisted of many members of ESW: Jenny Vu, Joey Leal, Samuel Donoho, Kristen Koike, Nicholas Pierson, Max Taubert, Chloe Ebeling, and Zahra Mehedi. Our team worked with the greenhouse manager on campus, Jennifer Bugge, who helped us understand the needs from a greenhouse and who this project will help. We were able to help many research professors and groups that nurse plants which will be used for research and for decoration around the university campus for everyone to look at. Not pictured: Chloe and Zahra

The monitoring system features a sensor that is able to track the temperature and humidity in the greenhouse as well as a camera that can be used to check for weather damage. The sensor we decided to use is the DHT22 from Adafruit which is capable of operating in temperatures ranging from -40℃ to 80℃ or -40℉ to 176℉ and in a relative humidity (RH) range of 0%-100%. It is accurate within 0.5℃ or 0.9℉ and 2%-5% RH. The camera is the OV5647 5 Megapixel Camera. All of the data can be exported onto Google Drive or it can be found on an app called Blynk. Blynk is an IoT service that allows microcontrollers and sensors like ours to transmit data over WiFi. It can also allow users to set a certain temperature/humidity range that the environment should stay in. If the temperature or humidity exceed that range then Blynk sends a push notification to the user’s phone alerting them to the anomaly. This is especially useful in cases where weather damage in the winter can cause cold air to leak in and there are less staff on campus to catch the issue in time.

Screenshot from Blynk app

components All the components inside the container

The sensor up close

The monitoring system placed in the greenhouse

graph The data from December 15th

During the past year, we ran into some problems such as the costs of some products and how COVID-19 affected the team. Materials were limited so it was somewhat difficult to test for data which slowed our rate of progress. Another setback was working during COVID-19 since communication between everyone was a little bit harder. Additionally, we decided to not use a carbon dioxide sensor as it was to expensive and we realized that the data wouldn't be as useful as other types of monitoring. A professor informed us that monitoring light levels are much more necessary. At the moment we are very close to having this feature implemented using a calibrated solar panel, but the calibration process took more time and was more difficult. The solar panel will be implemented in the future, with the calibration process allowing it to display sunlight intensity in ppfd (Photosynthetic Photon Flux Density) rather than a scale of 0-5 V. Another part we decided to change from our original plan is measuring bug density with sheets and a camera since the sticky sheets were replaced often by plant caretakers and they would be able to provide a more knowledgeable assessment of the sheet, how covered it was, and what type of bugs were present compared to any image analysis we could have implemented. Now we decided to use the camera to monitor for weather damage. We came to this conclusion since during the big freeze in Texas, there was some hail which damaged all of the greenhouses, and we realized monitoring for weather damage would be a better use for the camera.

Even with those setbacks, we were able to complete our main goal of the project and now plan to add more in the future. The most prominent addition to the project which neared completion in December is the addition of a solar panel in the device to read intensity of sunlight. This was requested by the greenhouse manager to monitor the plants and collect sunlight data from Blynk. The features of this addition would be giving instantaneous readings of sun intensity in ppfd (Photosynthetic Photon Flux Density) or possibly taking data throughout a whole day with settings entered by the Blynk user. The calibration process for the solar panel was aided by a grad student and professor in the college of Horticulture, and the panel should be ready to link with the Blynk app and installed soon.

Although we have a lot of ideas of where to take the project next, in the immediate future we plan on wrapping up the solar panel implementation and providing support and documentation to our end user.

NU - SmartTree: Summer 2021 Update

Added by Katie Lev 4 months ago

Even during the summer, SmartTree has continued to make progress on our structure! We are hopeful to begin manufacturing this upcoming quarter, so SmartTree’s project managers (Katie and Callista) decided to meet weekly for the last two months to finalize unfinished details from the spring.

A major portion of the work completed this summer consisted of Katie and Callista printing out CAD drawings for each part, previously completed by our team members in the spring, and then discussing each part individually. These conversations consisted of finalizing dimensions, manufacturing feasibility and material choice. They also spent a significant amount of time focusing on the top and bottom locking mechanisms, a topic of long discussion in the spring as the previous plans were not as feasible to manufacture as anticipated. Thus, our project managers came up with an alternate plan that they are going to propose to our teammates: create a metal-platform base with a 15 degree angled wooden wedge to hold an umbrella pier base for a pole of 3”.

Speaking of 3” poles, that is another big change that occurred this summer. Previously, SmartTree was planning on using a pole of a larger diameter; however, locating such a pole, especially one to fit our pier base plan for the locking mechanisms, does not exist. After doing some mathematical analysis, modeling the pole as a fixed-fixed beam with gravity and weather loads, Katie and Callista concluded making the pole size 3” with an inner diameter of 2.5” would not significantly decrease the structural integrity of SmartTree.

Katie and Callista also discussed the base pieces and base plates, or the giant triangular focus of the structure and its foundational element. First, they decided that the entire base plate (foundation) would be allowable to slice into 4 modular puzzle pieces rather than 8. Four pieces will not be unmanageable to manufacture nor move, and 8 pieces would lead to more complex tolerancing. For the base pieces (triangular center of structure), the lid for the center will fit on top of the triangular piece encapsulating the electrical home of the structure and will have no taper as water could perform capillary action and trap itself in the wood. The connection between the lid and center base piece walls will be lined with rubber to prevent water from seeping inside.

More minor decisions were considered this summer, all summarized on a spreadsheet placed in our shared team folder for easy reference. All general meetings between the project managers were also carefully recorded in our team’s meeting minutes folder. Katie and Callista are excited for team input and for the soon-approaching manufacturing phase! OH! And how could we forget… we now have a MINI-SCALED MODEL of our structure!!!! After Katie and Callista redid the CAD for each piece, Callista put extra hours in Ford Design Center printing each part. This model is supposed to act as a method for our new and returning members to better understand the structure. It sure helped our project managers identify missed details and holes within the project…

Hope everyone is having an amazing rest of their summer, and we will touch base once again this coming fall with even more updates on our structure!

Texas A&M Greenhouse Air Analyzer: Summer 2021 Update

Added by Jenny Vu 6 months ago

During the spring semester, we were able to order all of our materials, and we began to work on the temperature and humidity sensors. We also welcomed a new member, Sam Donoho, to the team. So, now we have the members Joey, Sam, and Jenny working on sensors, and Nick and Kristen working on the assembly and installation at the greenhouses. We have been able to successfully link cameras to the sensor where it can output the data automatically into a google drive or manually to as an email.

We have made a change to our original plan as we have been advised that the air level sensors aren't as accurate and instead measuring light levels will be more beneficial to the greenhouses. Now we are looking into photo diodes and seeing how we can make a more cost friendly one that is within our original budget. However, it is a new area for all of the members, so we are still unsure on what to do.

We are now planning to complete this project by winter 2021 as all the members will be back on campus to install the components at the greenhouses, and the light levels sensors and bug density sensors will be completed by then.

Educational Wind Turbine: Summer 2021 Update

Added by ESW Akron OH 6 months ago

The University of Akron’s Educational Wind Turbine Design Team’s goal is to produce a functional wind turbine with the purpose of showing the availability and practicality of wind energy. This team formed in January of 2021 and has made a lot of progress throughout the Spring 2021 and Summer 2021 semesters.

Progress made during during Spring and Summer 2021 include:

  • General research of current small scale wind turbines that produce about 300 Watts of power.
    • Considerable research was conducted in order to see how current small scale wind turbines are constructed.
    • Individuals independently researched and shared results on specific components including blades, generators, batteries, and towers.
  • Generator selected and purchased.
    • We found that many people repurpose permanent magnet motors and use them as generators for wind turbines and even hydro turbines.
  • Battery selected and acquired.
    • We determined that a 12 volt deep-cycle battery would be best for our project.
  • Blades selected
    • We looked into many ways of fabricating our own blades, but after understanding the requirements for each design it was decided to purchase blades that will sweep an area 62" in diameter.
  • Tower design and general layout of turbine revised
    • The tower has been designed to be easy to put up, safe, and cost effective.
    • The base of the tower pivots for raising the turbine.
    • The turbine will be able to turn into the wind as the top of the turbine is connected as a sleeve rather than rigidly.
    • It will be roughly 10 feet tall and be held securely in place through stakes at the base and at the end of the guy lines.

In the Fall 2021 semester, the Wind Turbine Team plans to:

  • Acquire the chosen blades
  • Finalize tower design and purchase materials
  • Purchase required wiring and electronics
  • Construct the wind turbine

General layout of the proposed wind turbine.

The Educational Wind Turbine Team

NU - AutoAquaponics: Spring 2021 Update

AutoAquaponics Progress From Spring of 2021
Added by Bill Yen 7 months ago

This quarter marks the 1-year anniversary of AutoAquaponics! Our work is far from over, but we have gone quite a long way from where we started with the outstanding innovation and determination of our members and the great support we have received from both Northwestern and ESW Global. Throughout this past year, we have been fortunate enough to be featured on a number of Northwestern's media as a result of our work. Check them out here:

  • McCormick Engineering Magazine, Spring 2021 (we made the back cover!)
  • The Daily Northwestern discussed how AutoAquaponics received funding from NU's Associated Student Government grant, which was put in place to eliminate barriers for students with creative projects
  • Northwestern's One McCormick webinar featured us as one of the leading student groups who continued to engage students in the NU community despite the COVID-19 pandemic

Now on to project updates, AutoAquaponics finished the year strong by completing the following during Spring Quarter:

  • Two 40 gallon grow beds that hold water
  • The structure and waterproof coating of our 110 gallon fish tank
  • A stand capable of supporting the full weight (~1000 lbs) of our fish tank
  • 3D CAD model of the entire plumbing system minus the PVC pipes
  • New features on our GUI program - export/indexing data by time and also more Control Panel subpages!
  • Approximately half of the controlling software that will allow us to toggle our remote-controlled outlet box and set it on a timer via Bluetooth Low Energy and an ESP32

This quarter we also welcomed Johnny Chen, Jake Turner, and Kayd Bhagat to our Electronics (Johnny) and Plumbing (Jake and Kayd) teams. They have all made tremendous contributions to the design and construction aspects of our project, and we're super excited to have them be part of AutoAquaponics! Over the summer, a few of us will continue to chug along with the plumbing and software portion of this project. We've plugged a number of lights into our remote-controlled outlet box and angled the camera attached to our Raspberry Pi at those devices so our Software/Electronics member can work on timing actuators and see them work in real time wherever they are.

What our setup in the club room looks like (camera is taped to cabinet on the right, and the outlet box/lights are on the left):


What members can see on our GUI (controlled devices are circled in red):

New feature on our GUI program - export/index data as CSV or plot them for further analysis:

The user interface we hope to integrate so that each light can be set on a timer:

Close-up view of the outlet box with an ESP32 microcontroller inside and a 16 channel relay:

outlet box

On the plumbing side, we've spent a lot of our effort completing the epoxy coatings on the two grow beds, water testing them, and building the fish tank. Building the fish tank was especially challenging, as most of our lumber and plywood arrived warped, which meant that our pieces would not match up well unless we bent each of them straight. This was achieved through a series of clamps and a lot of determination, and in the end we were able to ensure that the structure of the tank is strong enough to resist water pressure. All that's left for the fish tank now is to install a sheet of glass to cover up the cutout window on the front panel. At the same time we were doing physical construction, we were also creating a 3D CAD model of our overall system to help estimate our PVC pipe requirements later on. Enjoy these pictures of our construction process below, and a detailed tutorial of how we built these tanks will be released upon the completion of this project!

CAD of our entire system minus the PVC pipes:

It was important for us to sand/vacuum all the surfaces we applied epoxy to so that it adheres properly:

Our team member filling up our two grow beds to an appropriate depth and checking for leaks:

Our fish tank's humble beginning as pieces of lumber and sheets of plywood:

Cutting a window cutout on the front plywood panel with a jigsaw for our eventual glass installation:

Putting the tank together piece by piece:

Look at all the different types of clamps we used!

Completed back frame of the fish tank. The thick lumber support will prevent our plywood from bowing out from the water pressure:

We coating the inside of our fish tank with the same non-toxic, low VOC epoxy we coated our grow beds with. It took many coats and a lot of sanding/waiting for the epoxy to dry, but the gorgeous, glossy surface we ended up with made it worth it.

Coat 1, with just enough epoxy to soak into the wood and provide a good surface for later coats to bond to:

Having fun while painting:

The seams of the fish tank were reinforced with epoxy-saturated fiberglass to prevent water from escaping through the gaps between our plywood pieces (check out how shiny our dried epoxy looks!):

After we finished coating the fish tank, we attempted to install our fish tank glass. Unfortunately, we did not apply enough silicone to fill up all the gap between the glass and the front wood panel, which resulted in the tank leaking. We will be reinstalling a fresh piece of glass in the Fall with ample silicone to finish up the fish tank.

Fish tank after first glass installation attempt:

Our semi-completed fish tank (glass removed) stacked on the fish tank stand with our grow beds and sump tank:

A detailed list of our goals for the Summer and Fall can be found in our Project Completion Plan below, which we formulated for the ESW Project Grant committee. Northwestern is projected to return to all in-person mode in September, so we are optimistic that we will be able to get more timeslots in the machine shop and finish building everything we need. We are looking forward to having the first AutoAquaponics prototype up and running by the end of December. As always, we really appreciate your support, and please keep an eye out for more updates from us!

Not pictured: Raymonde Council, Jake Turner, Kayd Bhagat, Anna Lis

NU - SmartTree: Spring 2021 Update

Added by ESW NU 7 months ago


Despite remaining virtual throughout the duration of the Spring 2021 quarter, SmartTree continued to expand our group members and progress with our prototype by reviewing and finalizing the structure’s design in anticipation of physical prototype building in September. Callista Sukohardjo and Katie Lev were appointed as the newest co-project managers, filling the big shoes of former PMs Bryan Horn and Lauren Simitz. We welcomed back returning members along with a few new ones; our team now consists of Katie, Callista, Bryan along with Kai Veitinger, Polen Ton, Kane Feldman, Jason Jarrold-Grapes, Jake Turner and Ethan Zimmerman! Throughout the first few weeks of the quarter, our team learned how to create engineering drawings in Siemens NX software and the importance of geometric dimensioning and tolerancing (GD&T), having had both Bryan and Callista lead a brief session early in the quarter covering the basics of GD&T so that our team could apply these skills to our SmartTree project. Each member was then given the opportunity to apply these newfound skills by creating an engineering drawing of one component of the current SmartTree design. Below is a sample drawing of the foundation of our structure to be made of aluminum sheets:


Once the initial drawings were completed, each one went through several rounds of critiquing during group meetings, which aided in facilitating a continued dialogue on improving specific part designs. This process in particular helped our team identify flaws in logic or design that may have been previously overlooked or oversimplified in order to avoid costly mistakes during manufacturing later on. Currently, all that is still up to deliberation is the mechanism SmartTree is planning on using to access the electrical center from the top of the structure. Additionally, team members worked together to create manufacturing plans for each part, all of which were discussed during our weekly meetings. SmartTree would also like to personally acknowledge the help we have received from several members of the Northwestern community. Serving as a Northwestern Professor and ESWNU’s academic advisor, Harold Kung has given us much assistance and general advice on ways to approach the ultimate build tentatively starting this fall. Salomon Rodriguez, Northwestern Student Shop Manager, personally advised us on manufacturing queries SmartTree ran into during previous discussions. Bonnie Humphrey, NU Director of Design & Construction, and Stephen Camburn, NU Groundskeeper Assistant Foreman, helped us find great potential locations for our future prototypes. Among the list are East Tech Plaza, front of Mudd Library and the top lawn of Norris.

Overall the progress made during Spring 2021 was vital in our development of the SmartTree and ensured that we were all able to collaborate in a virtual environment and still make progress towards manufacturing our prototype in the near future. We now look forward to Fall 2021 where we hope to start manufacturing some of the key components of our SmartTree!

NU - AutoAquaponics: Winter 2021 Update

AutoAquaponics Progress From Winter of 2021
Added by Bill Yen 10 months ago

Now that the majority of our team members have returned to Northwestern's campus, AutoAquaponics has shifted its focus to building the plumbing and electronics portion of this project. We also welcomed Marcos, Anna, and Kaitlyn to our team, and we were thrilled to have them join this quarter and contribute to AutoAquaponics both virtually and in person. As a result of everyone's effort, we successfully manufactured two 24 gallon grow beds out of lumber and plywood. In Spring quarter, we will coat the grow beds with epoxy to waterproof them and get them ready for our plants, and build a much larger, 110 gallon container out of glass and wood for our fish tank.

Everyone helping to clear out space and unload materials for our system:

Team members working hard to build the two grow beds:

Completed product:

On top of plumbing construction, we also continued developing the electronic hardware portion of AutoAquaponics, namely a remote controlled outlet strip and an automatic water tester. Next quarter, we will aim to integrate these to our Raspberry Pi's GUI program by having the Raspberry Pi communicate with a number of ESP32 microcontrollers via Bluetooth Low Energy (BLE). As a result, we will be able to cut down on the amount of hardwiring we have to do and have a more modular and reliable system.

3D printed prototype of a peristaltic pump that can dispense very precise amount of water:

Raspberry Pi controlled outlet strip turning grow lights, heaters, and fans on and off fully automatically:

While the Plumbing and Electronics team rolled up their sleeves for construction, the Software team continued to add more functionalities to the AutoAquaponics GUI. This quarter, we completed the Settings page of the program, which allows the user to specify their preferred environmental parameters, and receive text messages when the detected parameters are not within the "safe" level. They can also enter their email to receive a weekly summary of what the state of the system is. In addition, we began adding subpages that the user can use to control the actuators in the aquaponic system. Eventually, we plan to have one subpage per actuator in the system so users can change their settings to whatever they like without needing to code.

Completed Settings page:

Water Pump page users can utilize to control the system's water pump:

Thanks for reading, and keep an eye out for more from NU AutoAquaponics next quarter!


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