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YS FLIGHT SIMULATOR Version 20181124

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Latrobe Westmoreland Air Show

For the first time in two years, I went to an airshow. Latrobe Airport hosted Westmoreland County Air Show over the Memorial Day Weekend. It's just 50 minutes away from Pittsburgh. I went there on Thursday to watch the airshow practice as well. For some reason, Westmoreland County Airshow is good at picking the worst-weather day for an airshow. The sky was clear on Thursday during the practice, and the weather was horribly bad on the weekend. Not just bad, it was cold like late February. Nonetheless, I was so happy to be able to watch Blue Angels again! (Read More)

The United States is almost back to normalcy. Restrictions after restrictions are getting lifted. No sign of the infection count coming back up. Pfizer, Moderna, and J&J vaccines must be soooo much effective.

I am also monitoring numbers from Japan. Especially around where my parent is living. The number is declining, but the problem in Japan is not the number. But, such a fragile medical system. The hospital system is as if it were in a developing country, which is overwhelmed by a tiny fraction of the COVID patients compared to the U.S. It is probably impossible to reinforce the hospital system in a short time. Only hope is to vaccinate as many people as quickly as possible. It's not just to return to normalcy. Developed countries must start helping others. To help others, first need to secure own safety. That's the basic. Developed countries should start sending vaccines to the developing countries, vaccines that really work, not the one that doesn't work.

What should have happened was Japan should have started mass vaccination at least two months, or if impossible a month, earlier. The number should have started declining earlier, more hospital beds should be available now, and there should be no reason to cancel or re-postpone the Olympic games. What's shame is people who are blaming the government's slow response were not doing anything either. The government was not prepared at all, but neither did the private sector. It is really a shame.


If your FitBit Charge 3 stops notifying anything including exercise alert

The quality of the computer software is consistently falling down like a rock. That makes me feel helpless now a days. The control software of FitBit Charge 3 is no exception. Probably from the wrong concept of agile programming. Programmers are thinking they can release something bad and then fix it in updates. The reality is they release something bad and never fix it. The concept of agile programming may not be wrong in an ideal world that doesn't exist, but if you take programmers' psychology into account it may be the worst idea.

I started wearing FitBit Charge 3 since I experienced a severe health problem last March. I thought I had a heart problem and wanted to monitor my heart rate especially while sleeping.

Now I am out of the health problem, but I keep wearing mainly for exercise alert every hour, but it suddenly stopped today after I replaced the band. Turned out it was a text-book case of bad user interface.

FitBit has a useless option called "Do Not Disturb", which kills whole purpose of FitBit. I don't know why this option exists at all.

What's really bad is there are two places you can set this option, and it is very easy to accidentally enabling one of them. If you long-press the only button, FitBit shows a menu to turn on or off "DND", which stands for "Do Not Disturb". Unless you have a good imagination, you may not see it means "Do Not Disturb". Meaningless use of short form. Worse, it is way too easy to accidentally enabling this "DND". Like when you are cleaning your FitBit, or when you are replacing the band like I was doing today, you need to hold the watch. You end up with accidentally enabling this "DND" menu because the watch thinks you are long-pressing the button. Then, you may accidentally touch the watch face, and "DND" is enabled without you even noticing it. This completes a creation of totally useless watch that gives no notification and display is too dark to be readable under the sun (even when you make it maximum brightness). This button design is also an engineering failure. I give F grade to FitBit.

OK. Here is the final blow. Whoever designed FitBit 3 control software decided to keep one "DND" option, and "Do Not Disturb" option separately in two different menus. "DND" and "Do Not Disturb" are no in sync. These are two separate options, and you need to turn off both "DND" and "Do Not Disturb" to re-enable notification. The user forum pointed that you need to turn off "Do Not Disturb". But, no mention about this "DND". It took several hours to find this critical flaw in the control software. I was lucky because I noticed this "DND" stands for "Do Not Disturb" when I long-pressed the button. If I didn't notice, I was almost throwing it away.

This is such a basic failure in the software design. Presumably whoever wrote this FitBit Charge 3 control software doesn't have a good education in user interface design. Is the control software written by a student? It's not a work of a professional programmer. It is made too poorly.

Why am I writing this? Because it is not just FitBit Charge 3 control software, but also the web program of the user forum is broken. I logged on and tried to add a comment on the discussion forum on the same problem, hoping to help some users, but "Reply" button was grayed out with no explanation. Hope who are experiencing the same problem finds this post with Google.

Will I keep wearing FitBit? Yes. Do I recommend FitBit? Absolutely not. Software quality is as if written by a student. I don't understand why I have to pay for this poorly-made program. Or, is the price of FitBit Charge 3 only for the hardware? Actually the hardware is not well designed either. I give F grade to the button that is too easily pressed accidentally. Also it is useless outdoor. Even if I set the brightness maximum, display is unreadable under the sun.


NASA Rocket Launch

As NASA has been trying almost for a week, Black Brant XII rocket on KiNET-X mission was launched finally today. It was visible from Pittsburgh for a few seconds. If it were not for a patch of clouds to the east of Pittsburgh, it could have been visible probably a few more seconds. I was scanning the south-eastern sky just like searching for traffic in the cockpit, however, my wife spotted before me. I quickly aimed and took this shot.


In the U.S., COVID vaccines are everywhere. There are some walk-in clinics that let you get a vaccine shot even without an appointment. It is very amazing.

There have been a discussion of effectiveness of the current vaccines on the mutants or variants, but I think we know the answer by now. The number tells at least Pfizer and Moderna vaccines are effective to at least currently-spreading variants. I'm looking at the news of the COVID clusters in the elderly care facilities. U.S. suffered from COVID clusters in elderly-care facilities in the early stage. However, after those who are in the elderly-care facilities, living or working, got vaccinated, I don't see a news about elderly-care facility clusters at all. Not just less of the news. I see absolutely none for the past a few months.

The variants are already in the U.S. But, we don't see a new COVID clusters in the elderly-care facilities. The conclusion is Pfizer and Moderna vaccines are protecting against variants. It may be less effective to the variants, but is effective to reasonably good level, based on what I see.

Counter data for this conclusion is the case numbers in the countries like Chile and Brazil. The numbers there do not slow down despite relatively high vaccination rate. The difference from the U.S. is majority of the vaccines used there are Chinese vaccines. This article of Nikkei newspaper tells that the efficacy of the Chinese vaccine is 54%. Far lower than Pfizer and Moderna. I also saw in another article that the efficacy of the Chinese vaccine is 2% after the first shot (Not twenty. It was two.), and about 60% after the second shot. I lost the link to the article. But, this article is saying the first shot of the Chinese vaccine does little to no protection. We don't have data to judge the efficacy of the Chinese vaccine against the variants, but what we are hearing from Chile and Brazil implies that Chinese vaccine is not protecting well enough.

Looking at the situation in Japan, I am frustrated of the slow vaccine deployment. I am hoping my friends and family gets vaccine as soon as possible. But, it is frustratingly slow in Japan. What frustrates me about Japan is not just slow vaccine deployment. The majority is blaming the goverment's response, but what about the private sector? In the U.S., the government didn't help much until the administration changed, but the private sector fought very well against COVID. In some places, hospitals were unfortunately overwhelmed and had massive casualties, but here in Pennsylvania, the medical system stayed strong. UPMC consistently has been saying they are prepared, and patients should not delay their treatment because of the fear for the COVID. The daily new COVID cases in Japan is about same as that of Pennsylvania. The population of the Pennsylvania is about 10% of entire Japan. Still Japanese hospitals are about to be overwhelmed. There is something wrong with the hospital system of Japan. If the government is not helping the hospitals, what private sector is doing? If Japanese government is deplorable, the Japanese private sector is equally deplorable.

When the COVID vaccine was approved last year, I thought there was going to be no problem in Olympic games. But, after looking at the blunder of Japan, I am feeling it may not be possible. Well, not just Japan. Those European countries who were laughing at the U.S. are now suffering from another surge. If European countries cannot send athletes, then it won't be worth running the Olympic games.

I've just had the second shot of Moderna vaccine two days ago. I had a flue-like symptom as advertised. I had fever, chill, and headache. It started about 12 hours after getting the shot, and lasted about 24 hours. I knew it was not real infection. Indeed there was no sore throat or cough because vaccine does not attack throat and lung. After 48 hours of the vaccine shot, I'm feeling better. I still have a light headache, but no fever or chill any more.


Free FM TOWNS Project.


I've flown to Seven Springs Ski Resort. Although I didn't ski since I was at 5,500ft in the air. (* There used to be an airport called Seven Springs (7SP) and you could fly into the ski resort in your general-aviation airplane and ski until several years ago.)

I've been writing my own MS-DOS V3.1 compatible DOS recently. The purpose is to replace MSDOS.SYS in one of the ROMs of FM TOWNS. In other retro PCs, some can run an emulator with a user-developed compatible ROM, or like MSX is an open standard, so you can run a retro game legally. As for FM TOWNS, the developer of UNZ emulator, Kasanova, has written an open system ROM. However, FM TOWNS has another ROM that has MSDOS.SYS, COMMAND.COM, and MSCDEX.EXE, which nobody was able to replace.

MSCDEX.EXE can be replaced with a compatible open-source module called SHSUCDX.EXE. I have been experimenting with it, and works with absolutely no problem. However, I still need MSDOS.SYS and COMMAND.COM which must be Version 3.1 equivalent. Actually to run SHSUCDX, it needs to identify itself as Version 3.3, but other functionalities can be Version 3.1 level.

Many of my friends asked if I can use FreeDOS. The conclusion is no. For some reason, the developer of FreeDOS mixed MSDOS.SYS, IO.SYS, and COMMAND.COM in one module. IO.SYS needs to be from FM TOWNS application disk or disc. Therefore FreeDOS cannot be used for a DOS variant like FM TOWNS. Software development is similar to chemistry. Once you mix chemicals, it is nearly impossible to separate them back to the original ingredients. Once you mix your software modules into one, it is very difficult to separate inter-dependent modules back to individual modules. I learned it hard way years ago.

If Microsoft opens MS-DOS Version 3.3, I wouldn't have to write my own, but Microsoft stopped short. They only opened up to MS-DOS Version 2.0. Better than nothing. At least I can read source code and compare disassembly to make sense of variables and flags. However, it is written pre-stoneage programming, or even before structured-programming paradigm. Hell of GOTOs. It is not practical to start from Ver 2.0 source code and morph it to Ver 3.1 equivalent. In fact, I cannot assemble it. I am suspecting some sources are missing. I'm wondering if anyone was successful in building MSDOS.SYS from the source code that Microsoft opened.

Unless the current (Japanese) copyright law changes wildly and it protects not only the developers, but also the software products, the situation stays the same. Strictly speaking you cannot run FM TOWNS emulator unless you own a FM TOWNS hardware. The number of working FM TOWNS hardware declines over time. If time t goes infinity, the number will become zero. Then nobody can run FM TOWNS emulator legally. Someone studying history of computer games 100 years from now won't be able to run FM TOWNS applications legally. I'd like to make sure such a person will not have a problem with copyright.

But, it will be too difficult if I start from zero because I cannot tell if I am writing correctly. So, I am writing it as a patch to existing MSDOS.SYS, and gradually taking over functions with my modules. It's like gradually eating original MSDOS.SYS. Kind of programming horror story :-) But, so far I successfully took over (ate) DOSINIT, PUTC(02h), FREAD(3Fh), FWRITE(40h), FCLOSE(3Eh), MALLOC(48h), FREE(49h), MREALLOC(4Ah), GETSYSVARS(52h). I am trying to take over FOPEN(3Dh), and it is tough as expected. I think I successfully took over a function (or procedure) to make up a full-path name with current directory and current drive taken into account (looks like called Fully-Qualified Filename in the DOS terminology). Then, I need to do media check, and then get to the directory sector. I think getting to the directory sector is very well defined, but I'm still vague about what to do with the media check, especially what I need to do if the media check failed. I'll see. I'm planning to make it open when it is able to boot into TOWNS OS without a single byte from original MSDOS.SYS. (Then I'll need to find an open COMMAND.COM somewhere or write my own.)


Johnson and Johnson's COVID vaccine is reportedly 66% effective with one shot.... Haven't we heard a similar number from Pfizer and Moderna? If I remember right (although I'm not good at remembering), Pfizer and Moderna vaccines are 60 to 70% effective with one shot, and 95% effective with two shots. Then, isn't Johnson and Johnson vaccine equally effective with two shots, but not just tested?


Wasn't it really COVID?

Actually,I really thought I was going to die last March. I had never experienced that bad health condition before. It took 3 months to fully recover. However, nobody knew much about COVID then. Only patients with cough and fever were tested for COVID, and I didn't meet the criteria. At this time, there is no way to tell if it was a COVID or something else.

It started in the first week of March. I had a very strange cough. I coughed like once an hour. But, just a single-shot cough. It never continued. Once I coughed, I didn't cough again for another hour or so.

Saturday 3/7. I felt sinus soreness. To be safe I skipped my bowling league. I took an over-the-counter cold medication before going to bed.

Sunday 3/8. My sinus soreness intensified. I stayed in bed for whole day.

Monday 3/9. I recovered as though I had nothing. I didn't even feel fatigue. I felt just normal. But, I stayed home and took a rest just in case. Luckily Carnegie Mellon was in the Spring break.

Tuesday 3/10. I felt really normal. My wife and I were going to the gym on Tuesdays. But, we started seeing COVID cases, and I had a cold-like symptom over the weekend. I asked our trainer if he was concerned, and he said no. So, we went to the gym as usual. And my trainer gave a pretty good (hard) exercise to me as usual. At that time, data coming out from Japan was suggesting very low fatality and severity. I was not expecting U.S. was going to mess up this much.

Wednesday 3/11. I experienced diarrhea and lost appetite. I got hungry, but after eating one or two bites, I felt full. I really thanked that CMU was in the Spring break. I was not in a condition that I could teach.

My body weight started diving down. I felt my stomach was digesting food extremely slowly. I think I lost 3kg (about 6lb) in a week. That was bad. If it continued 23 more weeks, my body weight would become zero. (Not really :-P) Beyond that, my mass will be negative. Does Theory of Relativity allow negative mass? (No worries...)

I was really lucky because CMU switched to online teaching after the Spring break. If my symptom was not from COVID, I was sure catching COVID on top of it was going to kill me.

Monday 3/16. Still I was feeling sick. Although I didn't have fever, not even elevated body temperature, I felt bad chill. I might have had problem breathing, but maybe not. It was so unclear symptom to me. I had to inhale strongly once every a few breathes. I was also getting a heart problem. My heart rate didn't go down below 70 even when I was lying down and doing nothing. Also the heart beat was so strong that my head was shaken on the pillow. I couldn't sleep. The best description of my condition was like after taking too much coffee. I felt I was going to faint at the beginning of my online lecture, but somehow I was able to get through.

Thursday 3/19. My wife's birthday. I pushed myself to get some Sushi dinner. As expected, my stomach broke again the next day.

Monday 3/23. I managed to finish my lecture without losing conscious. My body weight was still declining. I lost 10lb total from the beginning of the symptoms. The pace was slowing down though. I forced myself to eat some for dinner, but then I really felt sick. I really was worried my heart was going to stop. I visited ER. But, the doctor told that all the tests showed no problem in my heart. My SpO2 level was stable at 98% to 99%. I was feeling like dying, but my body didn't show any sign of problem.

Thursday 3/26. My PCP met with me. He told that it should be some virus infection, but it is unlikely to be COVID. He told me to believe in my own strength, and wait for a few more days.

Then I really started recovering in a few days. My fatigue didn't go away, but my heart-rate problem seemed to be gone.

Thursday 4/16. My heart-rate problem came back. The heart rate didn't go down. But, not as bad as in March. Just in case, I messaged my PCP, but he said if my condition is in general improving, it should go away.

I finally felt I fully recovered early June. It took whole three months.

If it was not COVID, what was it? I can think of two persons from whom I caught it. But, none of them didn't meet the testing criteria then. Therefore, they were not tested.

But, lately I saw an article that high heart rate while resting is one possible symptom of COVID. That was exactly my problem.

Well, because I lost my weight, I thought to keep that weight. But, it didn't work. I re-gained my weight. And, actually I was walking 10,000 steps per day, 5 miles indoor, spend 2500 Cal, but, it didn't work. I feel I started losing my muscle. And, I don't get sweat by doing it. And, maybe walking indoor without shoes on was not good for my knees. My right knee started hurting. I switched back to weight training and 1-hour exercise bike. FitBit is not smart enough to detect I am riding on an exercise bike.


Happy New Year!

Well, almost for sure this year is going to be a better year than last.

Let's hope the vaccines work as advertised and leave this pandemic behind soon!

[LINK to 2020 POSTS]

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