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Comment: Re:Learning how to learn (Score 1) 306 306

lol! YOU sir, are talented and full of esoteric knowledge. How much were you paid? Were you promised a full position, at least?

Yes, I had more than a full time position and esoteric knowledge is one attribute of an education. My degree was in engineering, but I took electives in everything from Geology to Technical Writing and many more. I spent most (30+ years) with one organization and made, and invested, enough that I have retirement income that is quite enough for me and in fact greater than my last official salary. I am still learning and staying active, but with projects and interests of my own.

Comment: Learning how to learn (Score 4, Interesting) 306 306

College is, or should be, learning how to learn. I don't mean taking more classes, I mean just learning what you need to know to get what you need done DONE.

I graduated with an engineering degree in 1970 and am now 68 years old and "retired." I retired as a network/security engineer back in 2007. Any idea as to how much of that was taught in college in the late 1960's? Well, actually NOTHING I worked on for the last 10 and very little of what I worked on for the 10 years before that even existed when I was in college.

An example of what I mean by learning how to learn is when our upper management decided in the late 1990's that their entire infrastructure based on Token Ring was not going anywhere and I was given the job of converting everything to eithernet. I was told we had a vendor conference in about two weeks to begin picking a vendor and the equipment that would best fit our needs. I knew very little about ethernet at that time, but was able to learn enough in just two weeks to be able to filter the BS and FUD out in the meetings and ask the right questions that needed answering. I did this on my own in my "spare" time by reading everything I could find about eithernet and all the vendors products we would be looking at. I had enough "education" to know how to learn this on my own very quickly. A background in electronics, knowledge of Boolean Algebra (yea, that is REALLY how a net mask works) helped, but were background to understanding how the new "stuff" worked.

There is a difference between education and training. With education you can learn on your own, sometimes with training your your "learning" becomes obsolete with the next change in technology. It is easy to remember the difference. Which would you prefer for your teen age daughter to attend -- a sex education class or a sex training class.

Comment: Re:Ask a Vet (Score 4, Informative) 235 235

In my case it was when I was trying to get home from South East Asia on emergency leave after my mom had a cerebral hemorrhage with a poor prognosis for survival. I landed at Travis AFB near San Francisco after being awake for most of 3 days travel with only a little cash, but a good balance in a Bank America checking account and the Red Cross at Travis said it would take them 3 or 4 days to get an ok to cash one of my checks. I gambled my last cash on a bus ride to San Francisco International Airport and fortunately Delta was happy to take my check for a ticket and I got home in time to see my mom in the hospital. That is my personal experience, I have heard GI's tell of much worse.

Comment: Ask a Vet (Score 2, Interesting) 235 235

I don't know about other veterans experiences with the Red Cross, but one I had over 40 years ago has kept me from giving them a dime ever since. I would not be surprised if many veterans had similar or worse experiences. I remember my Father talking about his during WWII, but didn't really understand until it happened to me.

Comment: Re:May be of some use (Score 1) 243 243

I know. A well designed circuit for battery power SHOULD work down to about 1.0 volts per cell. These are very old and very cheap sensors that are imports and do not come close to that threshold.

For the sensors I am using the average current drain is in the microamp range except when transmitting a reading, which takes only a few milliseconds, and are several minutes apart. The transmit current is in the low milliamp range, but so brief that the average current drain is less than one milliamp.

I do have and use eneloop rechargeable batteries in many other devices, but have not tried them in these since the 1.2 volts per cell is below the 1.34 volts per cell where the alkaline cells fail. However, I plan to try some the next time I have to change the batteries. Perhaps combining the voltage booster in the original post with the rechargeable cells would be the best of both worlds.

By the way, the 90's walkman was a far better case of engineering design than these sensors!

Comment: Re:May be of some use (Score 1) 243 243

Both your initial reply and addendum are good points. I do have a lot of eneloop batteries and charger and use them in my cameras and other places where ever they seem to work well. I have not tried them in these weather sensors (which are very old and undoubtedly poorly engineered) this is probably because when I take two 1.2 volt eneloop cells I get only 2.4 volts and these devices fail to function when the alkaline cells drop below about 1.34 volts per cell which is 2.68 volts and this is higher than the initial full voltage of two eneloop cells. Next time I have to change batteries I WILL probably try the eneloop's just to see if they work at all.

The sensors have average current drain in the microamp range except for a brief burst of only a few milliseconds when they transmit a reading. Then they draw several milliamps for that period.

Comment: May be of some use (Score 4, Informative) 243 243

I have a number of wireless devices ( remote thermometers, rain gauges, etc ) that use AA and AAA cells and I have tracked the failure voltage of most of them for several years. I fresh cell will be a bit over 1.5 volts and good design SHOULD permit operation down to about 1 volt per cell. However, virtually all of the devices I have quit working when the cell voltage gets below about 1.34 volts. The devices use between 2 and 4 cells each, and I have to change batteries in most of them between one and two times per year. I AM an engineer and understand that "there ain't no such thing as a free lunch" but most of the devices are low average current drain with intermittent higher current peaks (a sensor that transmits a new reading every couple of minutes). A device like this, with an appropriate capacitor for peak current (which most of the devices already have internally), would cut down the number of batteries I use per year significantly. For the price mentioned in the article I will buy a few sets of these as soon as they hit the market.

Comment: By By Google Maps (Score 2) 222 222

I haven't seen the new version, but did see the announcement. It looks like I will be switching to another map service since I don't use one of the browsers or OS's on their list of requirements. Too bad I used them often, but when pointy hair managers start making the decisions on what their customers want then end is in sight.

Comment: The good, the bad and the in between (Score 4, Informative) 96 96

I have had good doctors and I have had some bad doctors, but most of the doctors I have seen have been in between. In the mid 1990's when I was diagnosed with hypertension I bought a good automatic BP meter and have taken and recorded my BP regularly ever since. I also make notes when there are variations in either direction as to what MAY have been the cause, and try to make any needed changes in my lifestyle. I ALWAYS take my numbers to my checkups and most of the time the readings in the doctors office do not correlate well with the readings I get at home. I have even had it called "white coat hypertension" by more than one doctor. As a result of this over the years I have been able to reduce the prescribed medications, in agreement with my doctor, by well over half -- maybe more and my BP is within the normal range for me whenever I take it. And yes, I have checked the calibration of my meter.

Another issue I have had is the two lesser forms of skin cancer, many Basil cell cancers, and a few Squamous cell ones. Although I have a checkup by my dermatologist twice a year, most of the time I find something that I am suspicious of for him to examine. As recently as 2013 I had a very tiny growth very near my left eye that appeared suddenly in the late fall, shortly AFTER my exam. I was suspicious that it was a skin cancer and called and got another appointment for an exam. My dermatologist did a biopsy, which was positive for Squamous, and I was able to have Mohs surgery to have it removed before the end of the year. It was still small and the surgery was much less invasive than it would have been otherwise. If I had let it go until my next check up I would have had to have reconstructive plastic surgery in addition to the Mohs surgery.

While I am not a doctor, and never wanted to be one, I am very much in favor of any device that can let me monitor my own body and then find a doctor that will listen to me.

Comment: The State of The Art (Score 1) 397 397

I am a retired engineer who had a long and interesting career. The one thing that stands out in my mind is how much writing is involved in a technical career. Being able to do the work is often not enough. You have to be able to communicate with coworkers, managers, customers, and many others. The acronym STEM is in some places being replaced by STEAM, which stands for Science, Technology, Engineering, Art and Math. The phrase, "State of The Art" is heard often in engineering circles and most people do not understand that engineering owes as much of its heritage to Art as to Science. All of the basic machines were in use long before there was any science to understand them. The Romans, and before them probably the Babylonians, built amazing aqueducts without knowledge of the science of Fluid Mechanics. The steam engine was invented and put to use before the science of Thermodynamics was developed. However, it is only when Science/Engineering is combined with the Arts do we have the amazing burst of invention that has characterized the last century or a bit more.

Whether it is called STEM or STEAM one problem is that too many people think in terms of training and not education. There is a huge difference, and only when both Art and Science are taught with the goal of imparting a true and deep understanding of how the world works is it really an education.

A simple way to remember the difference is to ask yourself one question. "Would you prefer to have your teenaged daughter enrolled in a sex education class or a sex training class?"

Comment: A little history (Score 2) 132 132

Problems with injector design and combustion instability go back to to the Germans and the V2. They may have even been a problem for Goddard. The V2 engine is really a bunch of small combustion chambers at the top feeding into the main engine bell. I believe this was done, at least in part, to reduce the problems with combustion instability.

A much better and more efficient way to accurately simulate this process can really offer a lot in many areas, not just rocket engines.

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