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Everything posted by Sensei
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If you have Z protons in stable nucleus, and N=A-Z neutrons, (A is mass number, or Baryon Number), and you bombard it by free neutrons, There will be created new isotope. Z'=Z N'=N+1 A'=A+1=Z+N+1 f.e. O-16 + n0 -> O-17 If it's stable, nothing serious happens. But if it's unstable, it decays, sooner or later. Decay by Beta Decay Minus, or Double Beta Decay Minus, is the most interesting for you. As it will create isotope with Z''=Z'+1 N''=N'-1 A''=A' (in the case of Beta Decay Minus). Newly created element/isotope could be stable, unstable (moderate unstable or extremely unstable). If it's moderate unstable, you could repeat bombarding it by free neutrons, and create completely other element/isotope. Instead of free neutrons there could be used deuterium nucleus, or other ionized atoms, accelerated to high velocity to (at least) overcome Coulombs barrier (free neutrons don't need to).
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Part of energy used to do electrolysis is lost, and can be noticed as increased temperature of water. Hydrogen burning with Oxygen release energy, part of it is absorbed by device body and lost, it can be noticed as increased temperature of device. The same with electrons going through wires (not superconductor). If we assume 5% is lost in each cycle as heat, we can draw such graph: (to recreate graph make B2=B1*0.95 (or so), then fill entire column)
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Looking to expand my understanding of programming with CS
Sensei replied to hydropulse17's topic in Computer Science
To understand OS, you need to use OS functions directly, in C++. f.e. make test app "how to make window in Windows OS". It's done using CreateWindow. https://msdn.microsoft.com/pl-pl/library/windows/desktop/ms632679(v=vs.85).aspx *) Then make some buttons, listviews, controls. And learn how to attach functionality to them. Once you will learn above, you can add to it OpenGL. Or DirectX/Direct3D. Inside of control, or taking entire area of window, or full-screen. *) Windows window functions https://msdn.microsoft.com/en-us/library/windows/desktop/ff468919(v=vs.85).aspx Open every page, print them, then read them all. It's done by drivers. You would have to read Microsoft Driver Developer Kit (DDK later renamed to WDK) https://msdn.microsoft.com/pl-pl/library/windows/hardware/ff557573(v=vs.85).aspx -
That's why I was saying to our ex- ex- prime minister (and later ex- prime minister) they need to build factory of solar panels and gave them away (and install on the buildings) to people for free. Produce them locally, to be self independent, and not have to buy from asia countries (drain of billions). (As always) they didn't listen me, and instead they made 50% or more, supplementary payment. So if somebody bought solar panel setup and installed it, can go to government and ask for return of these money showing bills. When everybody have their own "power plant" on top of their roof, and walls, attack on the real power plants and power lines have less sense.
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Mercury, if you cool it down enough low..
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Create your own Universe. This job is already taken in this Universe.. ps. What is decay mode and decay energy of C-17.. ?
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Here nobody in IT looks at degrees in diploma. Knowledge is tested in (off-line, so you have no internet access) exam in company building. I was hearing multiple stories about interviews for local programmers. One (easy) question was: develop multi-thread safe stack/dynamic array, which will not use mutex (or other multi-threading blocking functions).
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Dispassionate view on the matter can only have 1) ignorant 2) billionaire 3) somebody who doesn't bother about money.. Giving up TPP/NAFTA by USA, as promised by DT, will obviously hit economy of countries from Asia, Mexico (increasing immigration!), Canada which could spread as wave of increased unemployed people, frustrated, without money to pay bills, and what might be worser to be unable to pay credits, which can lead to bankruptcy or serious problems of Asians financial sector.. (so if you are trading stocks short-sale Asians banks stocks) But what is IMHO worldwide worser is ignorance of DT about temperature increase of the Earth, saying complete nonsense that it's made up conspiracy etc, and his willingness to destroy all the effort made to heal the Earth... Did not I say already the all politicians should pass through IQ test exam? Now I will say, that the all politicians should have PhD in quantum physics to become even member of parliament, minister, prime minister, president.. Once they have PhD quantum physics done, can go other science or humanistic university, then to politics, when they are ready.. Idiots, cretins, should go to school, instead of being elected even to the smallest chair, with the smallest power to do something.. With their incompetence they can make huge disaster to plentiful of people.
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You have to have valuable knowledge for employer. Or you will end up in manual labour, or repeatable stupefying labour. Knowledge that you can show in PhD, license, history of work for other employers, or projects that you made for customers as freelancer. Programmer can work as freelancer. But you have to be good programmer, which means everyday writing programmer. Write applications for yourself, to gain experience, and not forget how to do it. *) You will be able to show them to clients, to show work you did. When you will have couple such applications, or one bigger, start calling/mailing companies (use phonebook for companies to learn their names), and asking whether there is something you can develop for them. F.e. utility which will increase their everyday work productivity. Companies need/should have website. Search for companies without website, or ugly/badly designed, and show them you can do it better. If you are not graphic designer, hire one for cooperation for work on single project. You will program in PHP/JavaScript/CSS, while graphic designer will make gfx. Restaurants can have on-line ordering system for customers. Search for restaurants without this feature, talk to bosses that you can make such system, and write it. (Better have code ready (without gfx, or with simple example template) prior calling them, so you will be able to show them how it will work, if they will hire you for this job). *) do you need to calculate something? Don't run Windows calculator application. Write one in .NET Framework by yourself.. One week of work. Do you need excel/spreadsheet? Don't run Excel/OpenOffice SpreadSheet. Write one by yourself. If you have calculator code, you also have ready function returning value for equation user entered. Repeat it in rows, and columns, and there will be basic Excel. Yet another one week of work.
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Comparison between couple different game engines. "Top 5 Game Engines (Frostbite, CryEngine, Source, Unity, Unreal Engine)" To create plants (f.e. grass), rocks, leafs, etc repeatable elements, there are used instances. There is kept just position, rotation, scale, and id of source element, etc. instead of the whole geometry of the all millions grass blades. To animate grass, leafs, to simulate wind effect, there is used vertex-shader (or GPU), to transform (translate, rotate, each vertex in element independently). To animate characters, organic geometry, there are used bones. Each bone has weight map with assigned to it vertexes. Typically one vertex is controlled by one bone, rarely more (some engines require one vertex-one bone). Rain, snow, fog, are typically implemented as sprites. Essential technique used in the all game engines, is double-buffering. It is used since '80 years. Engine renders to off-screen buffer, while user see on-screen, previously render buffer. Then they're swapped. Off-screen buffer becomes on-screen buffer, and on-screen becomes off-screen. Then it's cleared. And new frame is rendered to off-screen. And cycle is repeated. Without it, there will be visible blinking, and how CPU/GPU is rendering each triangle.
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No. Unless they're ancient one. Really ancient like from '90. Majority of modern games use full-screen OpenGL (so it can be easily ported to other platforms which support OpenGL), and full-screen DirectX/Direct3D (Windows exclusive games). Majority of modern games also use one of many game engines, like Unreal, Unity, and similar. Each major game producing company has their own game engine. Modern games also use vertex-shaders and pixel-shaders, built-in the all gfx cards, for maybe the last decade or so. Or even GPU (programmable f.e. 1024+ cores on board of gfx card) f.e. Counter-Strike: Source, and Half-Life 2, running on poor gfx card with poor implementation (or missing) vertex-shaders, pixel-shaders, didn't have bumpy water waves, didn't have reflections on water. No. When player is moving from location to location, between levels, between maps, they're unloaded, and new one loaded. GFX cards have very little on-board memory (at least in comparison to physical memory available to CPU), therefor 3D vertexes, triangles, textures must be loaded from physical memory to gfx card memory, for optimal performance. Say you have city. It's split to quarters, which at single time can be seen by player. Once player is moving from one quarter to other quarter, game is loading it. It could happen in idle time, while player is moving, in little chunks, so he/she does not have idea that there is transfer of data. When there is really large transfer needed, there is visible progress bar, to warn user. There is also often used fog-effect, disappearance of locations that are at large distance (Z-depth in screen-coords) (blending with black or white color). It's nice for user. But also shows where is quarter border, "end-of-world".
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Windows built-in firewall is poor firewall, See Sygate Personal Firewall f.e. Unfortunately this one does not work on Windows 7+ AFAIK. Check newer versions. But see video showing features anyway, look closely, to learn what such application has to offer.. You can set f.e. "application Firefox has to connect protocol TCP port 80, and nothing else (UDP/ICMP/TCP ports other than 80), otherwise you will be warned". You can log whole transmission packets/headers to log files. View them straight away a few seconds after transmission. When there is connection from application, that has no right to do it, you are informed and asked whether allow application or not, and you see packet in ASCII and binary. If somebody would put there your personal data uncompressed, you would see these data as they want to steal them. SPF is also making checksum from the whole app. If something altered app, or DLL was injected to app, it's no longer treated as the same app like before and no transmission allowed, instead user warned about hijacking of application. You learn what is MAC address of server, place it in router settings, and static IP is always given by DHCP (instead of randomization). Router/modem that I have special log with list of IP/MAC of computers that just tried to connect to it. So you connect machine to router, visit website, run router config, see what MAC was the last unassigned, assign in DHCP static IP to this one MAC, restart router, and renew DHCP.
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Nonsense. Personal firewall application (especially more advanced than Windows) installed on computer can allow/disallow any application using TCP/IP to do transmission or restrict to certain ports/protocols/time. Also hardware firewall won't prevent attack from intranet, when intruder is already in your LAN. f.e. somebody (f.e. laptop/smartphone) caught virus/trojan which is then scanning LAN and searching machines connected to it, and trying to find open ports, and exploit in operating system or installed 3rd party software .
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Clear entire buffer with char buff[512] = { 0 }; instead of: char buff[512]; buff[0] = 0; This would be better: void connect(string ssid, string command) { string cmd = "netsh wlan show profile | findstr " + ssid; FILE *fpipe = _popen(cmd.c_str(), "rt"); if (fpipe != NULL) { char buff[512] = { 0 }; bool exists = fgets(buff, sizeof(buff), fpipe) != NULL; _pclose(fpipe); if (exists) // Maybe do some quasi-parsing with strstr()? { cmd = command; fpipe = _popen(cmd.c_str(), "rt"); if( fpipe != NULL ) { _pclose(fpipe); } else { // inform about issue } } else { // inform about issue } } else { cout << "Failed to open" << endl; } } ps. Typical reason why somebody wants static IP address at home, or work, is that there is set up port forwarding on router/firewall. So every time the same computer gets exactly the same IP, the same as set in port forwarding configuration. But DHCP could be configured on router, to check MAC address of machine trying to connect to router, and assign all the time the same IP, even though computer has in its own local settings DHCP enabled. Google for "dhcp static mapping" (perhaps with "router [brand/model name]")
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Try netsh command https://technet.microsoft.com/en-us/library/bb490939.aspx You could call it from C/C++ also.
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I don't think so. You're denying yourself.. Since when Schrodinger was working with photons? Schrodinger was not experimental physicist.. Little amount of experiments done at early stage of his career, had nothing to do with Schrodinger equation AFAIK.
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Schrodinger equation is about probability of finding electron(s) around nucleus, at certain shell and sub-shell, while they're bound, part of atom.. While double slit experiment is about completely different subject (photon energy equation is E=h*f=h*c/wavelength)
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If questions are to check your CURRENT knowledge, and you have no idea how to answer them, shouldn't you simply say you have no idea, when you obviously have no idea, to be honest? If somebody (teacher) will see you answered question, he/she will assume you know the subject, and will give you even more advanced subjects, and you will be entirely fried.. Other example, somebody ask you something in French, and you answered (because you google translate it and copy'n'pasted), and then you meet each other in the real life, and he/she will be talking just French, you will simply have no bloody idea about what..
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No, when you have small resistance, you have small drop of voltage, as kinetic energy lost by electron traveling through element is very small. See my post #3.. Small resistance = large current. Because resistance in inversely proportional. [math]I=\frac{U}{R}[/math] [math]Q=I*t[/math] [math]Q=\frac{U}{R}*t[/math] [math]E=Q*U[/math] [math]E=\frac{U}{R}*t*U=\frac{U^2}{R}*t[/math] [math]P=\frac{E}{t}[/math] [math]P=\frac{\frac{U^2}{R}*t}{t}=\frac{U^2}{R}[/math] (some of these equations are "hiding" quantization at quantum level) ps. your teacher is asking about element type: resistor, capacitor, inductor, motor, lightbulb etc. etc. Circuit made with plain wires connecting negative and positive electrode on battery will blow up, damage wires and/or battery.. It's called short-cut/short circuit. https://en.wikipedia.org/wiki/Short_circuit
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In pure classical physics, charge Q is infinitely dividable. In quantum physics Q is integer multiply of e. Experiment in which e, elementary electric charge, has been calculated the first time, is oil drop experiment made by Robert A. Millikan and Harvey Fletcher. https://en.wikipedia.org/wiki/Oil_drop_experiment
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That's why people should start from quantum physics, then continue to classic physics, like in this one example.. "Voltage drop" (U1-U0)=dU multiplied by q is energy E, which is energy that's lost by electrons during traveling through some element. This energy is lost by electrons but still conserved, so element is heated, and have to radiate it away. If element has high resistance, they lose a lot of energy, large voltage drop on element, if element has low resistance, they lose little energy. small voltage drop on element. To travel through element with high resistance there is needed large initial voltage. (If element is superconductor, drop of voltage is so small that it's measured as near 0). Say U=230 V, R=100 ohm, therefor I=U/R = 230 V/100 ohm = 2.3 A But Q=I*t, so 2.3 A*1s = 2.3 C, but Q is quantizied every e=1.602176565*10^-19 C, so Q/e is quantity of electrons in wire flowing through it in 1 second period of time. Q/e = 1.43555*10^19 electrons per second. If we will have R=10 ohm, the same current I=2.3 A (and the same Q=2.3 C) could be achieved with just U=23 V. There are elements like transformer https://en.wikipedia.org/wiki/Transformer which try to transform large voltage with small current, to smaller voltage with larger current, U0*I0=U1*I1 U0>U1 I0<I1 (in practice there are loses) Again if you multiply both sides by time t U0*I0*t = U1*I1*t U0*Q0=U1*Q1 E0=E1 It's just energy conservation equation. Or electrons: U0*(Q0/e) = U1*(Q1/e)
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Run FileMon or something like that to learn which file service is talking about.. It's not possible to double click error entry to learn more details about it? Microsoft description of this error: https://www.microsoft.com/technet/support/ee/transform.aspx?ProdName=Windows+Operating+System&ProdVer=5.2&EvtID=13508&EvtSrc=NtFrs
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You know whats funny about this "SCIENCE" forum?
Sensei replied to Elite Engineer's topic in The Lounge
It's still possible to retrieve these data, within minutes or hours, and make graph with time on one axis. If you go to WebArchive and look up for scienceforums.net: https://web.archive.org/web/*/http://www.scienceforums.net You can see timeline when WebArchive made backup. After visiting one of these backups, f.e. https://web.archive.org/web/20160207181712/http://www.scienceforums.net/ We can see "12,803 topics 141,799 replies" We can safely truncate ID (which is yyyymmddhhmmss) and have it in yyyymmdd format (without time) https://web.archive.org/web/20160207/http://www.scienceforums.net/ Somebody could set up PHP script that will run through the all dates mentioned by WebArchive to get copy at certain time and date, parse it, to get number of topics/replies per section, and build local database. From which there will be possible to draw graph. And see how they grew in the past with time. Your links are often too advanced topics for them, I am afraid. I am trying to find wikipedia articles, easier to handle for layman. -
You know whats funny about this "SCIENCE" forum?
Sensei replied to Elite Engineer's topic in The Lounge
In your quite cool graph, you missed Speculations section (after subtracting Trash Can posts). It's bigger than Politics section (94k posts vs 92k posts in politics). -
What is your budget? I would search for something with built-in camera, and controlled by computer through USB/WiFi. Search net for "computer controlled telescope with camera" It showed this: http://protelescope.com/6-computer-controlled-reflector-telescope-with-digital-usb-camera