Doug Mejia

Note: This post was originally published on August 29, 2025. Due to technical issues, it was deleted and I am publishing it again today.

Digital Twins are virtual representations of the physical world—whether that’s a human being, a computer network, or an entire factory. Imagine having a digital twin of yourself that serves as a testbed for various scenarios. For example, if you’re suffering from high blood pressure, instead of trying different medications to see which works best, you could test them on your digital twin first. By feeding it your specific parameters, the system could theoretically narrow down the most effective treatment, since it’s essentially a replica of your own body. With AI integration, it could even suggest customized combinations of medications tailored specifically to your needs.

Another example is computer network management. You’d have your real physical network running in production, alongside a digital twin that’s constantly being experimented on and tested. This allows you to identify vulnerabilities and discover more efficient operational methods without risking your live system. AI-powered digital twins could predict potential attacks and recommend better security measures. At least, that’s the premise and promise.

The same concept applies to customer service. By feeding all the data recorded from real customer service interactions into a digital twin, companies could run countless scenarios to improve service quality. The system might discover ways to achieve better results with shorter phone or chat times per customer, ultimately enhancing both efficiency and customer satisfaction.

Although this is not a new concept, by any means, I think this sounds like a fantastic idea, and I only recently learned about it, which made me want to learn more. What really caught my attention was reading about companies like TwinHealth that are securing tens of millions of dollars in funding and investments, pushing their valuations to numbers with lots of zeros. I’m talking billion-dollar territory. There’s clearly something big happening here.

I know this might sound very “science fiction” of me, but it reminds me of Minority Report, where the “precogs” would predict someone committing a crime and authorities would arrest that person before the crime occurred. What if digital twin technology evolves into something similar? It’s a possibility, though perhaps not a high probability. It’s always wise to consider both the best and worst potential outcomes. Hopefully, we’ll land somewhere in the middle.

Not many things come close to celebrating a birthday with family and friends at the “Happiest Place On Earth!”

Home Assistant + Ubiquiti + AI = Home Automation Magic

It seems like every manufacturer of anything electrical that goes in the house wants to be part of the IoT story these days. Further, they all want their own app, which means you have to go to gazillions of bespoke software products to control your things. And they’re all - with very few exceptions - terrible:

Unfortunately, the quote above nails it right on the head. Every manufacturer out there seems to want you to use their app to control things around your house—from your AC unit to the lightbulbs to your water leak sensors. It’s gotten to the point where we may need an entire screen or folder full of these types of apps. All users really want is a central app that can control everything. Luckily, Home Assistant gets you most of the way there.

Of course, you do have to set it up on a Raspberry Pi or an old computer, but once you do, you’re off to the races. If you don’t have the expertise for that sort of DIY project or you just don’t want to take the time to set it all up yourself, you can buy a Home Assistant appliance that’s mostly plug-and-play.

We use HA on a Raspberry Pi at our house to control almost everything in our IoT network, mostly to control our lights with timers or dusk-to-dawn sensors. We haven’t gotten as far as controlling our hose’s water flow, but that seems pretty cool to do. Halloween is coming around soon—I’m just saying.

Warning! This post may not be suitable for all readers. Reader discretion is advised.

What It’s Like Watching Dozens of Bodies Decompose (for Science)

It sounds like a scene out of a horror film, but these places are real. They’re called taphonomic research facilities, or sometimes “body farms”—sites where forensic scientists study how the human body decomposes. (Don’t worry, the bodies are all donated.) By observing how fast cadavers break down in a controlled setting, investigators can learn more about decomposition and better pinpoint exactly what happened to dead bodies that are found in the real world.

A few years ago, I listened to an audiobook titled Stiff, and it was all about what happens to the human body after death. In this book, I learned about places where donated bodies are placed throughout the grounds of research facilities and exposed to various environmental conditions and the elements. The purpose is for scientists to study decomposition in order to train people in fields like forensics. Until that point, I had never heard of such a thing. Now I see that mainstream publications like Wired are shedding light on the topic. Although it’s morbid to think about, I find the science behind it all interesting.

Here is another view of the railroad spike knife I bought at a blacksmith shop in Tennessee.

Went to a blacksmith shop while visiting Tennessee and picked up this beauty as a souvenir. It is made from a railroad spike and I thought it looked pretty cool. The craftsmanship of the knife and the leather sheath was very nice.

Most students are using AI to enhance learning, not outsource it, research shows

Contrary to alarming headlines suggesting that “ChatGPT Has Unraveled the Entire Academic Project” and “AI Cheating Is Getting Worse,” we discovered that students primarily use AI to enhance their learning rather than to avoid work.

Despite this article having a limited sample size, it does seem to add to other research showing that students are not just using AI to “cheat” in school, but to enhance their learning by filling in knowledge gaps they may have. As an educator and a parent of two wonderful high-schoolers, I can vouch for this type of behavior. In my experience, most students want to do well in school and learn everything they can, and if AI systems like ChatGPT, Gemini, Copilot, and others can help them do that, I am all for it. It is up to us—parents, educators, and other community members—to help them navigate this world of ours and teach them to develop critical thinking skills so that they may discern what is fact, fiction, and everything in between. Question everything and find the source(s) of truth. In other words, trust, but verify.

I cannot believe that one of my favorite sites, ScreenCastsOnline, is 20 years old. I have been with them for most of that time. Although it has gone through some changes lately, it still remains great at what it has always offered… high quality tutorials for lots of apps and services. Thank you ScreenCastsOnline team! Keep it coming.

Check out Lee (current SCO owner) interview Don, the man who started it all back in 2005.

SIGN UP for a 7-day ScreenCastsONLINE trial membership TODAY and get access to our WHOLE CATALOG of over 1,460 videos.

New ARRL Book Release: Stealth Antennas for Ham Radio

Stealth Antennas for Ham Radio is full of antennas to get you on the air no matter where you live. Even radio amateurs who live with antenna restrictions or covenant limitations will find solutions in this book.

Home Owner’s Associations (HOA’s) are such a nuisance for Amateur Radio operators (a.k.a. hams), that the Amateur Radio Relay League (ARRL) has produced an entire book to offer options on how to hide your antennas in these restricted communities. I wonder how these people will feel when a natural disaster hits and they rely heavily on the knowledge, expertise and dedication of these hams to bridge communications between them and the authorities in the area or around the world, so they can get the help they may desperately need.

Thirty-three years ago today, I was a young teenager living with my family in South Florida. That August, right before the school year started, we decided to go on vacation for a week, completely disconnected from any news. Our sole focus was enjoying our time away. Then, on the way home, we turned on the radio, and between songs, a news broadcast announced that Hurricane Andrew was headed straight for South Florida, including our home.

My dad, who worked at a hardware store, immediately called his workplace to ask them to set aside some plywood, as we didn’t have any shutters. But wood were already sold out. He started calling around and finally found a supply of plywood in various pieces that we had to make do with. We bought everything we could and then began securing them to our windows. I remember drilling holes and putting them up with my dad, using tapcons, as the rain started. The outer bands of Hurricane Andrew were upon us, and we had to push through to secure the house.

With family visiting, we also had to stock up, preparing for potential losses of power, water, and other necessities. My mom, aunt, and sister went out to buy everything they could, but the supermarket shelves were virtually empty. They grabbed whatever they could find – Vienna sausages, Spam, and other foods we normally wouldn’t touch – knowing they would sustain us if we had to endure.

The storm hit overnight. We all gathered in our family room, as far away from the windows and French doors as possible, despite them being mostly secured with plywood. We truly didn’t know what to expect; it was our first hurricane ever. I remember hearing the gusts of wind and the rain, the barrel tiles flying off our roof, breaking onto the driveway, and hitting our cars. I don’t recall hearing any trees fall, but I vividly remember seeing them all leaning or lying flat on the ground, their root systems completely exposed.

Being inexperienced, I remember we went out during the eye of the storm. It was so calm, and we thought it was over, but then we heard it wasn’t, so we ran back inside. It was super eerie to hear such silence after hours of prolonged howling. We were among the lucky ones; our house sustained only minor damages, unlike others a little further south whose homes were utterly destroyed.

We saw trees twisted into corkscrews, and we were told it was due to tornadoes. People’s boats were found in other houses down the block. A friend of mine even had a boat on her property, and she had no idea who owned it. Nobody ever claimed that boat, and it was eventually taken away. I remember street signs lodged like Chinese stars into the sides of trees. I remember entire apartment buildings exposed, their windows, French doors, and sliding glass doors simply gone.

I remember houses with no roofs or windows, looking gutted from the outside in. I remember areas completely flooded, making driving through them impossible because you didn’t know what lay beneath the water. At best, it could have been debris; at worst, downed power lines or God knows what else. The streets were impassable due to fallen trees.

My dad and I, after ensuring our house was secure and clearing as much debris as possible, went down the main street next to our house. With machetes, we started cutting branches and moving them to the side so traffic could flow. Our thought was that an ambulance or fire truck would struggle to get through with all that debris on the road. I don’t know if it was the smartest thing to do, but it was the only way we felt we could help.

I can’t believe that 33 years later, I’m still remembering all this, and it’s all coming back to me. I think that’s the case for most Floridians who endured Hurricane Andrew. All you have to say are those two words… Hurricane Andrew… and they are immediately transported back 33 years, remembering even the smallest details that might seem insignificant to the overall event, but are just lodged in our memories forever.