Show of 02-02-2019

Tech Talk
February 2, 2019

Best of Tech Talk Edition

  • Segments taken from previous shows.

Email and Forum Questions

  • Email from Stu in Kilmarnock: Dear Doc and Jim. I would like to buy a satellite phone for use on my boat in the case of emergency. What are some good options? Love the podcast. Stu in Kilmarnock, VA
  • Tech Talk Responds: Not all satellite phones have the same coverage area.
    • Inmarsat — Inmarsat satellite phones work best between 50° North and South latitude due to their 3 satellites being positioned over the equator. The farther from the equator you are, the more your Inmarsat phone’s signal will rely on a clear line of sight to the horizon. This is a good option for most sailors.
    • Iridium— Iridium is also the only network (with 66 satellites) that offers global coverage including the poles. This is an option if are near the poles.
    • Globalstar— Globalstar is mostly limited to North America with a network of 40 LEO satellites.
  • Iridium’s Extreme 9575rugged satellite phone has an integrated GPS, an SOS button, and works anywhere on the globe, including polar areas. The 9575 has integrated GPS and an SOS button and lets you send and receive text messages and email, receive voicemail, and use it as a mobile hotspot. Maximum data speed is only 2.4 kbps, so short messages work best. Talk time per battery charge is up to 4 hours. All Iridium phones have the same service rates. The Iridium Monthly Wave Runner Plan, for example, provides 90 minutes a month for $100. Extra minutes cost $1.54 each. It costs $1,157.00 from Amazon.
  • Inmarsat’s Isatphone 2is a rugged, splash-resistant satellite phone great for marine use that works worldwide except for the polar regions. Built for marine life, the IsatPhone 2 is dust, shock, and splash resistant, and withstands 95 percent humidity. Battery life provides eight hours of talk time with 160 hours standby. The phone also has voicemail, SMS, and email messaging. A built-in GPS and emergency button sends a distress text to a pre-arranged number with your location. Inmarsat’s IsatPhone Mid Plan costs $65 a month for 30 minutes, with extra minutes costing $1.05. It costs $634.00 from Amazon.
  • Globalstar’s GSP-1700low-priced, regional coverage satellite phone has great voice quality and low operating costs. If you’re traveling or staying within one of the Globalstar regional coverage areas, much but not all of the world, the Globalstar GSP-1700 is a good option. The GSP-1700 doesn’t send or receive SMS messages and there’s no GPS, but you can get your longitude and latitude directly from the phone while in talk mode. Because Globalstar phones link with cell ground stations, they have far and away the clearest voice quality. The Globalstar phone also has voicemail. The Globalstar Orbit 200 minute plan provides 200 minutes for $100, with extra minutes for $0.99 each. It cost $499.00 from Amazon.
  • Email from Jim in the Studio: Dear Doc. I am setting up a payment system on my phone. Which is better to use, Paypal or Venmo? Both have interesting, but different, features. Jim in the studio.
  • Tech Talk Responds: PayPal is the long-standing, trusted payment service that created the digital wallet category. Venmo, the new digital wallet, has become so popular among Millennials that the verb “to Venmo” has been coined. Paypal went public in 2002. Venmo was created in 2012 and acquired by Paypal in 2013.
  • Venmo is part digital wallet, part social media feed. The app asks for comments on every transaction and these comments are posted, newsfeed-style, for friends to browse. Venmo’s website even explicitly states that the service is “designed for payments between friends and people who trust each other.
  • PayPal has diversified into other financial products and is beginning to resemble a bank more than a payment app. Venmo, on the other hand, is really good at what it does. It replaces cash when you owe a friend money.
  • Venmo is free to use. Credit card payments are subject to the 3% transaction fee that the card company charges, but debit card payments and transfers from a user’s balance cost nothing. PayPal charges 2.9% + $0.30 for payments from debit and credit cards but offer free transfers from PayPal balances.
  • Email from Betty in Fairfax: Dear Doc and Jim. I am retired and need a low cost mobile phone to stay connected. Most of the plans are beyond my budget. I rarely use my phone. Mostly it gives me connectivity when the electricity goes out in the house. What are my best options? Betty in Fairfax
  • Tech Talk Responds: Unlimited high-speed data, video streaming and mobile hot spot are now standard for most cell phone plans. Seniors, however, don’t need all of those expensive extras. Here are two low cost plans that may work for you.
    • T-Mobile:For just $3 per month, you can use any combination of 30 minutes or 30 text messages. Phone prices start at around $60, but if you have a compatible device, you can use it rather than buying a new one. You will, however, need to pay for a $20 SIM Starter Kit fee, whether you bring your own phone or buy a new one.
    • AT&T: The company charges the $2 fee only if you place or receive a call or send a text on that day. That fee is deducted from the prepaid balance on your account. Unused balances may expire if you don’t refill your account, so be mindful about topping up.
  • I would get an old phone from one of your children. Both T-Mobile and AT&T are GSM. This will save you the initial cost of a new phone.
  • Email from Jim in Bowie: Dear Doc and Jim. I am going on a trip to Europe and Asia. I would like to take my cell phone along. How should I prepare for this trip? Love the show. Jim in Bowie
  • Tech Talk Responds: You will need a GSM phone when travelling. Most phone support that technology (even Verizon supports both CDMA and GSM on its phones). Make certain that your phone is unlocked (will accept any SIM), if you want to get a local number. Activate Wi-Fi calling with your carrier so you can have cell like service whenever you are connected to a Wi-Fi hotspot.
  • Use VPNs (virtual private networks) to give you a secure connection on public Wi-Fi. These networks are frequently hacked, especially a high end hotel that have VIP guests. I use ExpressVPN on my phone and am quite satisfied. It is around$100 per year. However, you can get a monthly subscription.
  • Install your favorite VoIP messaging app. I use Viber and WhatsApp. I still have Skype, but do not use much anymore. Many use Facebook messenger, but not me.
  • Bring an adapter. Don’t use USB charging stations. They can be modified to steal data from your device. Be sure to also pick up a universal adapter or one that’s specific to where you’re traveling.
  • Get an international calling plan, if you don’t plan to get a local SIM card. I like the Verizon or AT&T $10 a day plan (only billed if you use your phone that day). If you plan to use only Wi-Fi, make certain to turn off data roaming or your emails will cost you dearly. Notify your carrier of your travel plans, including the countries where you will be travelling (some have to authorize the phone connection in those countries).

Profiles in IT

  • Rasmus Lerdorf, Creator of PHP
  • PHP and PHP Hypertext Preprocessor
  • Software engineer and Apache Web Server team member
  • First part of PHP was developed for his personal use in 1994
  • He used it for his personal web page and wrote as a CGI application
  • CGI (Common Gateway Interface) was a scripting language for server-side operations using Perl.
  • He released Version 2 which included a Form Interpreter for parsing SQL-queries
  • By 1997 PHP was being used on 50,000 web sites worldwide.
  • He turned it over to a core development team and “benevolent junta”
  • Zeev Suraski and Andi Gutman, two Israeli programmers, developed PHP3 and PHP4.
  • Growth of PHP Usage
    • By 1998, 100,000 unique domains used PHP
    • By 1999, 1,000,000 unique domains used PHP
    • Today more than 15 million domains use PHP
  • PHP had become another open source success.
    • PHP is easy to learn
    • Allows you to create a database driven web site quickly and easily.
    • PHP5 is the current version, which seeks to incorporated object oriented programming methods.
    • Conclusion: Rasmus Lerdorf was a man with a vision who wanted to share it with the world via open source.

Scam of the Week: Laptop Battery Life Estimates

  • Laptops promise anywhere from 15 to 24 hours of battery life, but you will be lucky to get 10 hours. Those estimates are not wrong, and there’s no mistake: Manufacturers choose the most unrealistic benchmark with the highest numbers.
  • If you look close, you will see the words “up to” before the battery life estimate. The manufacturer does not promise 16 hours of battery life; it promises “up to 16 hours.” You will get 16 hours in the ideal, perfect circumstances—not under regular PC use.
  • Here is a secret: It’s all about video playback. Manufacturers start playing video on the laptop and time how long it takes for the laptop’s battery to die. They just let a video play until the laptop dies, and that is it. They might disable background features and set the screen brightness to lower than normal levels, too.
  • Unfortunately, constant video playback is not representative of regular use. Modern laptops (and smartphones) use hardware-accelerated video decoding. The laptop has special hardware in its graphics processor unit (GPU) that efficiently decodes the video while using as little power as possible, keeping CPU usage down.
  • Manufacturers don’t care whether this represents your experience or not. They use this benchmark because it produces the longest battery life.
  • Rather than relying on manufacturer benchmarks, it’s best to find independent reviews of the laptops you’re considering buying. For example, while Microsoft touts up to 17 hours of battery life on the Surface Book 2, Anandtech found it lasted for about 9.7 hours while browsing the web.

First Ride on the Bird Electric Scooter

  • Easy to locate with GPS system in app
  • First time required a driver’s license scan
  • First time required reading and agreeing to terms of use
  • Starting the scooter manually by pushing with one leg
  • Then hit the accelerator and speed up to 15 MPH, which is too fast for the sidewalk and too slow for the road.
  • Lock the scooter after riding is easy, but a picture of the scooter must be taken.
  • Overall a good experience.

The Physics the Powers Hurricanes

  • Scientists have long known that hurricanes that hit the Atlantic coasts of North and Central America are born in storm systems off the west coast of northern Africa.
  • These wettest of storms are driven by weather over one of Earth’s driest of places, the Sahara (the name means desert in Arabic).
  • These small turbulence travel from east to west in the jet stream.
  • Hurricanes form near the equator over warm ocean waters. The term hurricane is used only for the large storms that form over the Atlantic Ocean or eastern Pacific Ocean.
  • The generic, scientific term for these storms, wherever they occur, is tropical cyclone.
  • Hurricanes are among the most powerful of all natural phenomena. They get their power from the condensation water.
  • The latent heat of vaporization of water is 2.256 MJ/kg. That is, it takes 2.256 million Joules of energy to boil one kilogram of water.
  • Of course, the reverse is also true. When one kilogram of water condenses, 2.256 million joules of energy become available.
  • The necessary ingredients for a stable hurricane are
    • A large area of warm ocean water (preferably at least 27 C).
    • Latitude of at least 5 degrees (North or South)
    • Vertical instability (low pressure at sea level is a good choice).
    • Minimal vertical wind shear (no jet steams please!).
  • Of these conditions, the first provides the energy, the rest allow the storm to get organized into a self sustaining pattern that concentrates the energy.
  • First, air rushes in to fill the low pressure region (item 4 above). As the air moves in, moisture in the air condenses and releases energy, which in turn warms the air reducing its density. This warm air rises, pulling more air in from around the outside.
  • All of this air rushing in towards the center is subject to a phenomenon called the Coriolis Force, that occurs due to the motion of the Earth. Overall, the storm picks up a counterclockwise rotation in the Northern Hemisphere and a clockwise rotation in the Southern Hemisphere. It is this process that requires moderate latitude, the Coriolis force is zero at the equator, and is insufficient to organize the storm below about 5 degrees.
  • So, we now have a great deal of wind rushing in towards a center and rotating counterclockwise. If there is a great deal of wind shear (difference in wind speed vs. altitude) the storm can be broken up before it really gets going. However, if the rising column of air in the center can operate, then the storm really gets going. Up at high altitude cool air is pumped outwards away from the center of the storm, this allows more hot, moist air to be sucked in towards the center at sea level, The moisture in this air is condensed heating the air further and driving the whole process faster. Eventually, the center becomes the familiar “eye” of the hurricane.
  • The hurricane can continue for many days over so long as it remains over open, warm water. Over land, the lack of moisture and the increased friction will destroy it rapidly.

Hurricane Forecast Computer Models

  • The behavior of the atmosphere is governed by physical laws which can be expressed as mathematical equations.
  • These equations represent how atmospheric quantities such as temperature, wind speed and direction, humidity, etc., will change from their initial current values (at the present time).
  • If we can solve these equations, we will have a forecast. We can do this by sub-dividing the atmosphere into a 3-D grid of points and solving these equations at each point. These models have three main sources of error:
    • Initialization: When the model starts, if it has an incorrect picture of the initial state of the atmosphere, it will generate a forecast that is imperfect.
    • Resolution: Models are run on 3-D grids that cover the entire globe. Each grid point represents of piece of atmosphere perhaps 40 km on a side. Thus, processes smaller than that (such as thunderstorms) are not handled well
    • Basic understanding: Our basic understanding of the physics governing the atmosphere is imperfect, so the equations we’re using aren’t quite right.
  • The best hurricane forecasting models we have are “global” models that solve the mathematical equations governing the behavior of the atmosphere at every point on the globe. Models that solve these equations are called “dynamical” models. The four best hurricane forecast models—ECMWF, GFDL, GFS, and UKMET—are all global dynamical models. These models take several hours to run on the world’s most advanced supercomputers.
    • ECMWF: The European Center for Medium-Range Weather Forecasting (ECMWF) model is the premier global model in the world for medium range weather forecasting in the mid-latitudes. In 2006, the ECMWF made improvements that starting producing very accurate hurricanes forecasts.
    • GFS: The Global Forecast System model run by the NWS. Excellent graphics are available on the web from the National Center for Environmental Prediction.
    • GFDL: The NWS/Geophysical Fluid Dynamics Laboratory model. The GFDL model that provides specific intensity forecasts of hurricanes. Detailed GFDL graphics are available at NOAA/NCEP.
    • UKMET: The United Kingdom Met Office model. Data from this model is restricted from being redistributed according to international agreement, and graphics from the UKMET are difficult to find on the web..
  • The best forecasts are made by combining the forecasts from three or more models into a “consensus” forecast. Over the past decade, NHC has greatly improved their forecasts by relying on consensus forecast models made using various combinations of the models. NHC forecast has been hard to beat over the past few years.
  • The single best-performing model over the past two years has been the ECMWF. This model out-performed the official NHC forecast in 2010 for 3-day and 4-day forecasts, and in 2009 for 4-day and 5-day forecasts.

European Model is Better at Predicting Hurricanes

  • American and European models have been at odds. In 2012, the American GFS predicted Hurricane Sandy would fizzle over the ocean. The European model anticipated a more disturbing scenario: the storm would turn west and strike the East Coast. Sadly, the Europeans were right. Sandy struck the Eastern Seaboard, causing at least 233 deaths and $75 billion in damage.
  • Overall, the consensus among meteorologists and other scientists is that the European model is better overall in forecasting weather.
  • The main differences between the two approaches lie in data simulation, computing power and the underlying physics used by each.
  • To run these weather track models, scientists start by gathering information about the atmosphere from various sources, including ships, balloons and satellites. Then, using simulations, the data points are packed onto a grid, essentially creating a three-dimensional description of the atmosphere.
  • The Europeans are better at this because their simulation system is better, and they use more data than we do in the US.
  • The European system also draws on more computing power, which enables the model to run on a finer grid, allowing higher resolution and better forecasts.
  • Another important component is the underlying physics used to determine the differing physical properties of clouds. Here again, the European centers do a better job.
  • In addition to running the models at the highest resolution possible to obtain the most accurate forecasts, scientists also conduct something called ensemble models, which allow them to determine the accuracy and consistency of their prediction.
  • To do this, they run simulations at slightly lower resolutions under different hypothetical conditions to determine where the uncertainties are in the forecasts.
  • The European system runs 50 of these cycles, whereas the American GFS only runs 20.
  • The superiority of ECMWF is largely due to Europe’s willingness to invest in software and spend on computers. So they get better results.