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Comment Not easy for top-notch grade (Score 5, Informative) 47

Disclaimer : Korean here, but trying to just state the fact.
Making HF in small lab settings, or in low grade is relatively easy. Making mass manufacturing facility of top-grade pure HF suitable for semiconductor making process(99.999%) is taking a lot of money&time and, above all, really hard. I think only few fully developed(Maybe US, UK, Ger, Fra, Rus, Jpn?) country can make pure grade of it, and for some other reason(perhaps safety&environment concerns, economical concerns) now only japan is major supplier of that pure grade material. And since HF is very toxic, reactive, unstable compound it can't be contained for a long time(3 months) without dropping quality so shipping distance longer than korea-japan(very short) have some disadvantages too.

Comment Just separate the network (Score 2) 89

Not a federal agency, but a company who happened to have just installed 9 cheap ~$50 hikvision wired ip cameras. There are 2 concerns.

1. default password is weak/predictable - it's up to you to setup it well.
2. The cameras may send the videos to unwanted entity. - setup the cameras into separate, unreachable network.

Don't mix cameras into normal office network. give it separate network which the camera can only see itself, and recorder. Then make sure only recorder itself is connected to outside network. Ah, you also can't trust your recorder? Take a software-based recorder that is known not to cheat you. There are many, including open-source shinobi, zoneminder, bluecherry, or well known commercial softwares not from that camera maker. So basically your recorder is a PC with masquerading gateway like network topology except it isn't routing anything between two network. Unless that cheap camera is sophisticated enough to literally hack your linux/windows ssh/rdp reachable recorder box you're safe. I've implemented the recorder with debian stretch backport with newest kernel(4.19bpo) + shinobi + athlon GE 200 based cheap pc +10TB hdd + 9 camera in 100mbps network and thanks to 200ge's hardware mp4 acceleration it works recording 9 1080p mp4s without any hiccup(also tried atom cherry trail, but its workload exceeds slightly over 2 so I changed to 200ge).

One last word, did you choose the chinese camera with wifi to reduce wiring hassle? Now security-wise there is no way to prevent hacking with conventional way if you don't trust the camera and you pay the consequences. Don't choose wireless models.

Comment Industrial data harvesting & label printing (Score 1) 328

Posting nearly same thing twice and this isn't redundant. Interesting. The company I work for has hundreds of primitive machines that just have basic model PLCs(no ethernet, just rs-232) and suddenly our customer wanted to collect all of data it produces on db & print label on each product it produces with lot information for no additional cost so it had to be made cheap. Typical Industry solution requires tens of thousands of dollar(proprietary data terminal that can connect to at most 2 or 3 machines at once at 1000+$, additional h/w installation cost(posts, wires..), proprietary s/w harvesting platform that can communicate with that proprietary terminal. Printing not included). Here's what I did.

hardware : raspberry pi 3b + usb-serial cable + power + microsd 8GB + Label printer for each machine
OS : Linux Of course,
SW : program made with Lazarus/FreePascal(Since DB was moving target so it had to be DB agnostic)
                    read from serial using synapse event based serial comm. component(compatible with both Delphi and Lazarus)
                    upload each product result data to db
                    autoupdate : rsync with server on boot(initscript)
                    read predefined form(ZPL II format) replaces needed element, write it to printer device(/dev/usb/lp0)

Done. With huge saved $$$.

Comment I still use it well(kinda), on linux (Score 1) 217

Not original Delphi, but its open source derivative, Lazarus(and its base language, Free pascal). 99% compatible(and still improving). Open source with PORTABILITY- Can be used on many mix of OS/HW/DB(windows, linux, x86, arm, mips, Oracle, MySQL, Postgres, MSSQL ...). It's literally "Compile once, connect to any DB, run everywhere, at native speed!". No one use Pascal? its language(without OOP) and runtime library function is roughly equivalent to that of plain C, so it's really easy to learn/educate if you're willing to do. It's OOP part is also easy to learn if you make some project with GUI elements.

I once had to make a program/system that harvest some data from 100s of factory machines(each with PLC, serial port), to DB which was still moving target("We have not decided which DB to use, yet"), with autoupdate capability, with different printing labels to each product it produces, with cheapest possible budget("It's kinda extra request from our customer.. but we have no power, so we have to provide it at no additional cost. so.."). Typical Industry solution requires tens of thousands of dollar(proprietary data terminal that can connect to at most 2 or 3 machines at once at 1000+$, additional h/w installation cost(posts, wires..), proprietary s/w harvesting platform that can communicate with that proprietary terminal). Readers at here could imagine cheaper solution without Lazarus(windows + atom board + vb or vc that cost windows license+intel board fee/ or some rpi board with API heavily depend on that DB platform). Using lazarus with $35 rpi(+$5 usb-serial converter +$3 phone charger+$3 8GB microSD card) eliminates all of that shortcomings. Additional installation space? just install it beside PLC with some spacers. It's that small. DB changed? Just change one line. Done. Autoupdate? rsync with program server in initscript. Done. Event based Serial communication? There are some 3rd party components for Delphi so naturally compatible with Lazarus too. Label printing? TStringList.LoadFromFile("labelform.txt"); (replace elements in TStringList); TStringList.SaveToFile("/dev/usb/lp0"); Done with customizable form for each different machine.

By suggesting this solution, I was able to save HUGE $$$ off of my company, and most importantly, Shut the fsck off the unbelievers(of open source, lazarus, rpi, linux.. ) to the point that now they never question my technically right solutions anymore.
Ha! that was fun.

P.S. This was happened at 2015 and now maybe this can be done with python(without native speed? I dunno), too. But Lazarus/FreePascal have one more subtle merit - one more subtle layer of job security - and I love it.

Comment Better idea - should I patent it? (Score 1) 251

Make the recycle information MACHINE READABLE and put(print) it everywhere!
This would not solve human laziness, but it would prevent unnecessary information loss after disassembly with minimal cost increase.
And this would change 'Not recyclable unless I put this fscking mess into gas chromatography - practically not recyclable' into 'Just need more labor, I would adjust the price accordingly' recyclable material.
This would even help 'willing to recycle but confused(I'm not sure if this jell-o top film is vinyl or plastic?)' consumer, because practically everyone now have universal barcode reading device - smartphone.

Comment What I want : Real mobile PC without compromises (Score 2) 243

What I want :

1. Integrated REAL keyboard - no virtual kbd, no separate bluetooth crap that I must manage its separate battery charge status, can STAND BY ITSELF and GUARANTEED TO STAY IN ONE PIECE on irregular,vibrating surface like bag on my lap on subway so no separate keyboard with kickstand or magnet connected like MS surface/current netbooks
2. Lightweight for mobile gaming - can be used continually with two hand grip(like nintendo DS) or one hand grip(like smartphone). In my experience the upper weight limit is somewhere around 400g~500g
3. NO castrated storage - cpuwise Atom is OK you can even use OLD generation low power Atom like Z530(2W)+yucky imagination GMA500 GPU to run dosbox/SNES emulator/2d games rather well. Current Atom(after bay-trail) with REAL INTEL GPU can even run lightweight 3d games well if you set the preferences low. All the slowness comes from its slooooow eMMC raw flash(no parallel tricks like SSD) storage especially it's write speed is painfully slow.
4. adequate memory - minimum 2GB
5. good battery capacity - minimum 10 hours for light use/3 hours for heavy(gaming) use.
6. OS freedom just like PC - install & use linux just like pc without problem. android? I'll install android myself if necessary.
7. NO castrated USB(like having only 1 micro usb that also used for charging - huge headache for charging&attaching external devices simultaneously)
8. REAL connector to external display device - NO MIRACAST CRAP

For now I have one that satisfy 1,2,7,8(now discontinued UMID mbook SE) I hope to find one that satisfy all my requirements(plus more)

Comment What I did : Hold policykit-1 to version 0.105-4 (Score 1) 755

(Boilerplate warning - this info is as of 2015-02-16 only, this info may be incomplete or incorrect, this may not work for you, or your environment)
For wheezy -> jessie users who do not want to manually compile packages AND keep systemd out of the system.
First, go to "options->preferences" menu on the aptitude and uncheck "Install recommended packages automatically" checkbox(or do equivalent on synaptic). This will also make your system more managable(stops installing unwanted packages).
Then HOLD OR DOWNGRADE POLICYKIT-1 PACKAGE TO 0.105-4 - this is the last version that don't depend on systemd related library. If you don't have this version, get this version manually from net and install it using dpkg.
I think all bad things starts from this package. - if you hold this(and be careful), you'll still be able to enjoy many of the improvements of jessie without installing most of the systemd crap(even systemd-shim). After this, there will be 2 problems left to your general desktop user experiences.
One is about login environment -> this relates to the fact that not long ago most of the display managers(gdm3,kdm,lightdm) became dependent on logind included in systemd(again corrected in kdm,lightdm so these 2 are safe again) - if you're paranoid, just use slim or wdm or xdm(since these 3 are ugly, you'll need some additional tweaking) instead and DON'T FSCKING USE GNOME3(gone are the days when one can install gtk/part of gnome2 libs only freely to use standalone(not gnome related) gtk2 programs. Gnome3 become more intermingled like windows) or XFCE4(core functions of xfce depends on libpam-systemd). If you are using LXDE, don't install lxde task since this depends on several packages which again depends on systemd. Install lxde-core task instead and invidual packages you want to use on LXDE(oh, and get/tweak pygtk-shutdown from net instead of existing shutdown button of LXDE to enable shutdown/reboot). Other simple WMs don't need to worry(just worry about DMs).
The other is printing. CUPS on jessie depends on colord which depends on libsystemd0 and policykit-1 so unless you use CUPS on wheezy version there is no simple way to prevent libsystemd0 from being installed on your system, but you can still prevent other systemd crap if you hold polcykit-1(systemd, libpam-systemd, etc.)
Packages to avoid like plague - policykit-1(0.105.5 or later) - Unlike others who are helpful about reducing unnecessary systemd dependency, the maintainer of this package is vehement about keeping libpam-systemd(and dropping seemingly still working consolekit) dependency to this nearly essential package for desktop(see bugreport #747105 yourself), libpam-systemd - this package depends on systemd directly even with systemd-shim present on system.

Comment My theory : It's Capacitor (Score 1) 602

I have no scientific data to back it up, but I strongly suspect both CFL and LED's premature burnout problem arises from using cheap,low-grade capacitors(Both needs capacitors for power conversion circuit). And I think LED last longer than CFL just because LED draws less current from that same cheap,low-grade capacitor so that it's less damaging to that crap.

Comment Recipes (Score 1) 238

There is more than one way to do it.

1. Raspberry Pi(not practical)
RPI+linux+iptables+openvpn
pros : cheap, low power(5W), no noise, low heat
cons : 1 100Mbps port only, usb-ethernet/usb-wifi+additional switch needed, usb performance not good. Not recommended unless your outer ethernet side is very slow.

2. DD-WRT + supported hardware(ap/router)
AP/router(typically arm based)+linux+iptables+openvpn
pros : relatively cheap(depends on hardware model), low power(typically 10W), no noise, low heat, integrated WIFI/wired ports. small. clean looking.
cons : limited internal storage/memory. May brick your hardware if you are not careful enough(and void your warranty) useful for dedicated role(firewall, vpn)only
                    may use for printer/file server or other role if your hardware has usb port, but (typically) slower than full pc.

3. Mini ITX based PC
Low-end bay-trail based Mini ITX motherboard(j1800 recommended)+dc-dc power+12V power brick+small case+storage+linux/bsd(?)+iptables/pf(?)+openvpn
pros : versatile(file/full printer(cups)/application(ex. minecraft) server capable depend on configuration, up to 8/16GB ram + TBs of storage),
                  still can be made fanless&no noise if you've planned well,
                  relatively low heat(warm) if you leave it on open space
cons : most power hungry(~15W, depend on configuration), additional usb-ethernet adapter/switch/wifi needed, biggest of all above(20cm*20cm*5cm + brick)

tips
-for cheap 12V power brick, look for power brick for LCD monitors(12V 3.5A/5A SMPS - depend on your system's power usage- widely manufactured)
-about iptables, read iptables tutorial on frozentux.net
-p910nd - light, spoolless(no file operation) print server daemon. turn your cheap usb only printer to always-on networked printer even on limited storage platform.

Comment Could it be improved by... (Score 1) 138

attaching some additional pieces of hardware like some rubber, plastic pad, spring ,small stick to make it behave like real joystick? I remember that there were some hobby projects to make something attached to MSX numpad to make it work like joystick long long ago.

Comment Cheaper material (Score 1) 149

Roughly 3 yrs ago the company I work for noticed that Price of Nylon 12 resin had been steadily rising. Once asked, representative of resin manufacturer said "Oh, they're hugely popular replacing fluoropolymer based plastic(PTFE-teflon I think) in solar panel(in china)." While Nylon 12 is still better than more common plastics for this purpose, it is definitely less durable and cheaper alternatives to fluoropolymer.

The Military

United States Begins Flying Stealth Bombers Over South Korea 567

skade88 writes "The New York Times is reporting that the United States has started flying B-2 stealth bomber runs over South Korea as a show of force to North Korea. The bombers flew 6,500 miles to bomb a South Korean island with mock explosives. Earlier this month the U.S. Military ran mock B-52 bombing runs over the same South Korean island. The U.S. military says it shows that it can execute precision bombing runs at will with little notice needed. The U.S. also reaffirmed their commitment to protecting its allies in the region. The North Koreans have been making threats to turn South Korea into a sea of fire. North Korea has also made threats claiming they will nuke the United States' mainland."

Comment Still not good enough for me(just my opinion) (Score 2) 103

What I want for my ultimate mobile computing device:

1. Small, lightweight and have physical keyboard
  I walk a lot so I want small device that fit comfortably in my backpack (so that's below 7'') and weight less than 1.5(preferrably 1) pound. I'm not all-day mobile warrior so I can live with cramped keyboard but after testing my wife's galaxy s2 touch keyboard I decided I DO NEED a physical keyboard for typing documents/playing games(like nethack, old dosbox compatible games).

2. MS application/IE compatiblity
    I need to do business with MS office documents and MS IE only internet banking/payment processing. Libreoffice is not good enough if you have to edit/exchange MS office documents with other business entity(and that stupid and powerful entity is stubborn enough that it want genuine MS office docs only and complain slightest of incompatibility problems)

3. Very low power
10W - It will still need fan or huge heatsink. Moving part/high power is not good for longivity/ruggedness let alone battery life. My estimate is that you'll have to go below 2W to acheive compact & sleek design without fan/huge heatsink - Yes atom Z5XX do that and I have one now.

4. usable graphic core without fsckup.
I need graphic core that supports linux well and play angry bird. PVR core in atom don't support either. Even their xp driver don't support basic opengl well enough.

5. Support basic net tools/secure net connection I feel comfortable
I want to redirect all normal net connection via VPN using my secure home base using openvpn when I connect to untrusted/public wifi. I believe that is reasonably achievable(without heavy source modifying/manually recompliling) with only linux/winxp~7 for now. And I hate OS that don't support basic net tools.

6. Trusted application that I know What it is doing.
I don't want application that does unknown things behind my back(leaking private info for whatever reason or doing net connection I don't want it to do). So I prefer well known/open source apps and become skeptical on many android/google apps.

If you go ultrabook route, you can acheive 2,4,5,6 for now.
If you go atom route, you can achieve 1,2,3,5,6 for now. Currently I've settled for this.
If you go arm based smartphone/pad route, you can achive 1(depends on device),3,4,may be 5 (if you rooted your phone/pad) for now.
With WINRT device, may be you'll be able to achieve 1,2,3,4.

Of course things are changing so somewhere in future may be you could do things with a platform that counldn't do for now(compatibilty/standard compliance got better,intel finally make 2w non-atom processor/drop FSCKING pvr core from atom, better performance to run emulation comfortably, corporation changes their mind about privacy...). So I think it is the race between platforms which acheives the most within reasonable time.

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