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  1. CCD, as opposed to CMOS on 111-Megapixel CCD Chip Ships · · Score: 1

    If used with a really expensive, high-speed analog-digital converter (ADC) capable of digitizing ~2700 million pixels per second, then it could reach a good 24 fps speed, but that's about 40 times what is needed by a HDTV camera CCD (1920x1080 interlaced at 60 fps). Normally this conversion speed is only available with a specialized high frame rate set.

    Image sensors work by converting light to electric charges. More light in an area makes the pixel hold more charges.

    Images captured by CCD are converted to digital by having the ADC scan electric charges across pixels of a line, and line by line across the sensor, so a big CCD would take longer to scan because scanning has to be done sequentially.

    If they made it CMOS, then each pixel can convert its electric charge to a digital value at the same time, so digitization is done parallelly. At least in terms of the rate an image sensor can pump data out, CCD has a bottleneck that, theoretically, CMOS doesn't have.

  2. Re:OMFG on Finding Programming Work on the Side? · · Score: 1

    I don't know about getting paid programming work out of your free time, but I can tell you about getting fruitful personal projects: a personal project would only motivate you if it solves your own problems.

    Here is what I do on my free time and why I do it.

    Since I'm a graduate student, I'm pretty acquainted with LaTeX because my job (writing papers) depends on it. So I agreed to typeset a book written by a friend, in Chinese. For that, I'm using XeTeX, which is an extension of TeX that has very good multilingual and font support. However, I've noticed a typesetting trick or two from professionally published Chinese books, so I've been spending my time figuring out how to write TeX macros to accomplish that.

    The motivation is to deliver what I promised to my friend, and the end product (the macros I write) is something I can share with the community one day.

    Another example is a "linkiconv" program that I wrote. I have some files whose names were in some legacy character encoding, be it latin1, big-5, or something else. Nowadays I standardize on utf-8, so I wrote a program to convert file name encodings for me in order for the names to show up correctly.

    This program is not released because I'm not happy with the fact that it is written in Perl, and that it requires Text::Iconv module to work. I don't expect many people to install that, and I think Perl is overkill for what I try to do here. I'd like to have a similar program written in C to link with libiconv directly.

    However, my own problem has been solved, so rewritting the program in C never happened.

  3. not so much of a fud but "heads up" on Real RFID Hacking Scenarios · · Score: 2, Insightful

    I think you underestimated how a read-only RFID tag can still be subject to play-back attack. You can fake the presence of an RFID. This becomes a problem when the person deploying RFID doesn't understand the consequences. For example, since perimeter security assumes that authorization is equivalent to the presence of an ID, being able to fake RFID violates this assumption and breaches security.

    TFA mentions a couple of these examples, where deployment is flawed. The flaw is not in the RFID technology.

    As for encryption, if the RFID always echoes back the same cipher-text, then it is still subject to play-back attack. Encrypted authentication is only useful if there is some sort of challenge-response protocol. I'm sure you know all this.

  4. factual error in TFA about SHA-1 on Real RFID Hacking Scenarios · · Score: 4, Informative

    The last sentence on page 2 says: "Compare that to the hundreds of years experts estimate it would take for today's computers to break the publicly available encryption tool SHA-1, which is used to secure credit card transactions on the Internet."

    This is incorrect.

    SHA-1 is a digest algorithm. You give it some data, it outputs a 160-bit string that represents a fingerprint of the data. This fingerprint does not allow you to reconstruct the original input, but you can use it to verify data integrity, that data have not been tempered with. This does not protect against eavesdropping. Hacking a digest algorithm means to find, in a reasonable amount of time, two different inputs that produce the same digest.

    SHA-1 is not a cipher. A cipher takes plain-text and a cipher-key in, and produces cipher-text out, which would appear to a third person without a cipher-key as a pretty random string.

  5. lyx on What Should One Know to be Truly Computer Literate? · · Score: 1

    I recommend LyX, which is kind of a GUI frontend for LaTeX in "what you see is what you mean" fashion. I started with LyX and I've learned LaTeX gradually by looking at tidbits of LyX output---you can export documents to LaTeX from LyX. Even now that I'm more familiar with LaTeX, I still write my papers almost exclusively in LyX.

  6. Re:What's new exactly? on 8 MegaPixel Digital Sensor Unveiled · · Score: 1

    It sounds like the press release hints a breakthrough in the CMOS manufacturing process but is stripped of any serious technical details.

    Pixel count alone, as the rest of Slashdot comments already concurred, doesn't usually mean too much to the casual photographer. But pixel count breakthrough on CMOS sensor means a lot to the manufacturing plant, since every pixel comes with its own digitizing circuitry, and high pixel count means the circuitry becomes very dense. To make this possible, it is likely that a new CMOS manufacturing process has been developed.

    Maybe Micron acquired or developed new nanometer fabrication technology and wants to impress its investors. Or maybe it's trying to get the customers (digital camera and mobile phone makers) excited without leaking too much business secret. Either way, we get a watered down press release like this that doesn't make much sense.

  7. on the topic of projection... on One Big Bang, Or Many? · · Score: 1

    Don't need to hurt your brain by trying to visualize these higher dimensions. You end up "projecting" these higher dimensions to three dimensions---the way you recognize the world around you---anyways. I remember some said that a four space-dimension creature could appear to us that his head is at his tail. This is nonsense. This only happens when we project the creature to our three dimensional space.

    To get back to your comment, I think string theory is meant to address phenomenon that appears to us as being "projected" onto our space. Some physicists found something at the quantum level that doesn't seem to work in three-dimensional arithmetic (they found that creature with his head at his tail). To explain this, they come up with an equation that involves higher dimensions and a projection function from that space to our space. The projection function is necessary so they can verify the model by experimenting in our space.

    But I think they're chasing their own tails. If they apply that projection function to their equation throughout, they end up getting an equation in the three dimensional space, which they could have formulated without the higher dimensions.

    I think string theory is more of a mathematical trick than a model of the universe.

    (Yes, this is all strawman argument. If anyone wants to be more specific, we can talk about functors and category theory more.)

  8. Re:Loss of privacy on French Town Tests Cashless Society · · Score: 1

    I guess the government is doing all it can do to create jobs for some people. When those "man in black" visits become more often, I won't be surprised to see books and training courses that teach you how to deal with them.

  9. Re:Loss of privacy on French Town Tests Cashless Society · · Score: 1

    This would only become a problem when they start banning cash transactions. Maybe somebody cried wolf when credit cards are introduced, but most people are okay with it.

    Furthermore, if you will, your dollar bills have unique serial numbers attached to it, so whoever spends the dollar bill can be traced. If you want to be paranoid, you could use gold transactions. However, gold can be traced by its mineral content to the mine. Depending on your purpose, this may still be a problem.

  10. Re:Problems of design on An Alternate Human · · Score: 1

    What do you mean "Evolution isn't some flowchart of fixed and discrete processes. It's simply the result of the survival of the fittest."?

    1. Genetic mutation.
    2. Natural selection.
    3. Repeat 1.

    Didn't I just express evolution in terms of a flowchart? The whole process may be much more non-deterministic and concurrent subject to race conditions everywhere, but you can write it down in a plain language.

    By the way, Schrödinger's cat is a concept of logical exercise, not a process. Please don't mention things that are off-topic.

  11. Re:Problems of design on An Alternate Human · · Score: 4, Insightful

    Designs are oversimplistic, inflexible, assume fixed conditions in the environment, and cannot function beyond their designed requirements specifications.

    You must be a Windows programmer.

    Evolution has proven superbly effective at creating workable systems...

    Suppose I design an evolution process that is effective at creating workable systems, then by your claim, my design (evolution) must be oversimplistic, inflexible, assumes fixed conditions, and cannot function beyond specification. This is a contradiction to your claim, so evolution process must not be effective, or your statement about design is wrong.

    ...because any component which is serious suboptimal causes the extinction of the entire line that contains it

    Instead of "serious suboptimal causes" you should use the word "defect." Of course, no matter which words you use, your claim is a useless tautology, since a component that extincts is a component that has defect and vice versa.

    But if you just say suboptimal, you can easily find someone who is biologically superior than you, then by your claim you should be extinct. But (I hope) this is not the case for you. There is observably some give or take on how suboptimal you can be. However, this implies that evolution is not so effective because it allows suboptimality, therefore a contradiction to your claim.

    I hope other scientifically curious people are much more logically rigorous than you when defending evolution.

  12. scale by hashing on How Far Can Large Commercial Applications Scale? · · Score: 2, Insightful

    I'm still studying computer science with little practical experience, but you can divide certain aspects of your application by hashing---you hash datasets or queries. This distributes the workload across a cluster of computers. However, implementing hashing requires you to make intrusive changes to your code, and maybe most companies aren't willing to do so. Hashing generally has to be implemented from the very beginning, which requires foresight. Google is the one company that does it well.

  13. Re:Naww... on Missing Link Found Between Human Ancestors · · Score: 1

    You're trying to be funny, right? Or insightful? I can't tell.

    Either way, I'm flattered that you compared my earlier, absent-minded remark with the great work of Charles Darwin.

    As you pointed out, "code reuse" is vague, and in terms of computer programs this can mean several things:

    1. Linking a program against a static library.
    2. Linking a program against a shared library.
    3. Copy and paste code.
    4. Using a template that can be instantiated for different uses.

    I'm afraid I can't be more specific than that. I'm a computer scientist. This field is responsible for all the wonderful things you use on a computer, yet---you won't believe it---everything is so vague here.

    The language, C, used to code most software you run on your computer, doesn't have a rigorous semantic! It is up to the interpretation of whatever compiler is used. The processors in your computer, be it Intel x86, Motorola PowerPC, or whatever, don't have a rigorous semantic associated with their instruction code either! It's not meant to have a rigorous semantics, as most optimizing processors execute the code out of order non-deterministically.

    Everything we have on a computer is based on guesswork. Yet it works. You have to embrace vagueness at some point. It is inevitable.

  14. Re:Naww... on Missing Link Found Between Human Ancestors · · Score: 1

    Does it ever occur to you that all living things share 90% of genes because God practices code reuse? That is divine software engineering.

  15. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    It looks like you don't know the bible well enough to claim that something it says "doesn't seem true."

    Christian religions contradict the bible on a point or two because of someone's misunderstanding of the bible. It has nothing to do with the bible itself.

    Suppose I give truth tables of "AND", "OR" gates to a group of monkeys, but none of them can derive the correct truth table for "A AND (B OR C)", then is my truth table at fault?

  16. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    You clearly have a contradiction. You think certain birth rights are inherently yours naturally for granted, but you blame the lack of these birth rights on a creator.

    You don't sound like a true athiest to me. If you are, you would shrug off the terrible things that happen to innocent people as something by chance or consequential of natural law, which serve no basis to prove or disprove the existence of God.

    In the atheism framework, the ability to choose between good and evil is purely incidental. You do not have it as a birth right. Moreover, neither good nor evil has a meaning. If everything happens by chance, then these tags---"good" and "evil", "suffering" and "joyce"---are simply assigned to certain things arbitrarily. In fact, this is how a search engine sees the world.

    Clearly, you can see any discussion in this framework falls into a dead end, and no more meaningful discussion can take place.

    You will only find a solution if you're willing to follow the way of God.

  17. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    my grandfather was the pastor of the Pentecostal church in the town I grew up in.

    If my understanding of Pentecostalism is correct, they have an emphasis that persons baptised by the holy spirit can speak in tongues, especially one for a mystical language.

    I think this is a misunderstanding of Acts 2. The disciples, upon receiving the tongue of fire, spoke in tongues of existing languages spoken by nearby regional people: Parthians, Medes, Elamites, ..., Cretans and Arabs. These were not random utterances or a mystical language. The purpose of that is so the disciples can reach out to different ethnical groups and spread the gospel.

    Furthermore, in 1 Corinthian 14, Paul addresses the issue of speaking a mystical language. Someone in the Pentacostal church should have noticed this.

    " 6 Now, brothers, if I come to you and speak in tongues, what good will I be to you, unless I bring you some revelation or knowledge or prophecy or word of instruction? 7 Even in the case of lifeless things that make sounds, such as the flute or harp, how will anyone know what tune is being played unless there is a distinction in the notes? 8 Again, if the trumpet does not sound a clear call, who will get ready for battle? 9 So it is with you. Unless you speak intelligible words with your tongue, how will anyone know what you are saying? You will just be speaking into the air." -- 1 Corinthian 14:6-9.
  18. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    I agree that I have authority to rule over evil in my life, and I do my best to keep it under control. The evil I was talking about in my post isn't in my life. Right this very moment there is a child being raped. There is a man being tortured for speaking the truth. There is an adulterer ruining a family and enjoying it. The last light is leaving someone's eyes from starvation, and they never had a chance to experience great joy. And a million more tiny crimes, too. That is the evil I was talking about.

    If you know you have the authority, it should be your best interest to tell other people that, they too, can have this authority if they believe in God, and to teach them to use it. A Christian should not keep one's faith to oneself (see Matthew 25:14-30).

  19. Re:I'm always amazed... on Evidence of the Missing Link Found? · · Score: 1

    I really appreciate you putting so much time constructing an essay, and I hate to see it go to waste, but I really don't have time to read carefully through every single words.

    I just have a question for you. What does evolution buy us? Other than the purpose of back-tracking to the origin of species, what does it predict of the future species? Genetics is science. Natural selection is science. But evolution for explaining the origin of species is not.

    From my point of view (cut and pasted from your own words with evolution and intelligent design exchanging places), all arguments in favor of evolution are actually just arguments against intelligent design with the assumption that evolution somehow "wins" by default if the prevailing answer turns out to be wrong. And the reason why evolution "wins" by default is due to some faulty application of science.

  20. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    Full disclosure: I was raised as a Chinese-Pagan syncretised Buddhism. I was never atheistic because I believed in Buddha and the spiritual world, though there was a time I had strong resentment on Christians because I had a tough time growing up as a teenager and I blamed it on them. I supported evolution, rejected and ridiculed creationism. About a year ago I admitted Christian faith, and I believe the decision was made on an informed basis.

    I've lurked on Slashdot much longer than I become a Christian. I've never tried preaching on Slashdot, but it's worth trying.

  21. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    But it seems quite understandable that any all-knowing, all-powerful, all-good God could allow the evil that has happened to have happened. And saying that it's okay because it's the next life that matters is a cop-out: if this life doesn't matter then why have it at all?

    Christians, as daughters and sons of God (1 John 3:1), have holy spirit dwell in you (Acts 2:18). You have the authority to dispel evil (Mark 6:7, 13). God also wants us to share his glory. "In him we have redemption through his blood, the forgiveness of sins, in accordance with the riches of God's grace that he lavished on us with all wisdom and understanding." (Ephesians 1:7-8).

    Since you are given all the authority to rule over evil, what more do you want? You just have to keep in mind that this authority does not come from you, but it is from God. I don't know your circumstance for being unhappy with your life, but I think learning to be a Christian is a long and gradual process, and that you didn't try enough before you quit.

    I do know some people who walk with God already enjoy success in their lives, given to them by God's glory. It appears to me that this life is important. I don't know where you get the impression that you can simply look forward to after-life in heaven and waste this life.

    A lamb that belongs to God will never be lost.

  22. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: 1

    When we talk about evil, people usually attribute it to Satan. However, Satan was first created to be the most beautiful being of all things, anointed as a guardian cherub and adorned with precious stones in the garden of Eden (Ezekiel 28:11-19). But he chose to betray God.

    If you look up Ezekiel online, note that subject in Ezekiel's discourse is King of Tyre, but Tyre is used to allude to Satan.

    God did not create evil. His most beautiful creation turned evil on him. God knew this would happen and already foretold the destruction of Satan.

    You can ask why did God create Satan knowing he would turn evil and bring suffering to the people? My understanding is too shallow to answer this question, but I believe that God is doing this for a globally optimal solution. When you look at it locally, it may not be optimal. It's not a greedy algorithm.

  23. Re:God created everything... on Study Explains Evolution's Molecular Advance · · Score: 1

    That's okay, we can look at this matter in a more light hearted way.

    Imagine a scientist looks at an ancient CVS repository of the Linux kernel and notices that the source code evolves and branches. He is able to compute the diffs between each source code revision and to recall an early snapshot of the Linux kernel. He concludes that the code must have evolved on its own.

    Moreover, he claims this justifies that Linux kernels must have evolved from a monocellular organism, which kind of makes sense because Linux kernels are monolithic kernels. If it wasn't monocelular at its origin, how can it be monolithic?

  24. Re:The truth shall set you free. on Study Explains Evolution's Molecular Advance · · Score: -1, Offtopic

    You never know, there are creative ways to get out of a paradox.

    In the old testament, God mandated laws that people should follow and specified punishments for breaking the laws. However, if that is the end of the story, we would be extinct by now. Humans just can't follow the laws, but God wants to give each of us a chance to redeem and be forgiven. Yet God does not logically violate the axioms that are laws he set to stone.

    Here comes Jesus, the son of God representing God himself, who takes the responsibility of all our sins and crucifies for us. The only condition is that we believe he is authorized by God to alleviate our sins.

    Theorem An all powerful God is impossible.

    To break out from your first paradox, if I were God, I would create a stone, specifically not to lift it myself, and create a being authorized by me to lift the stone. Since I'm able to designated a being to lift it for me, I am able to lift the stone indirectly, and still satisfy the conditions set forth by your proof.

    Your other examples, such as married bachelors, are inherently inconsistent in the definition, so in order to keep the logic consistent, these definitions cannot be admitted. But again, there may be creative ways to break these paradoxes.

    Ever wonder why computers, a being created by humans, is strictly logical but is not creative?

    Theorem A God that knows everything is impossible

    Breaking out of this paradox is similar to breaking out of Russells paradox. You simply need to restrict the domain of "everything."

    More over, there is a hole in your proof. We cannot assume the powerset of any infinite set is bigger than itself. We know that for any set A, powerset of A has the cardinality 2^|A|. Consider A to be a set where |A| is a tower of 2's, that is, |A| = 2^(2^(2^...)), then |P(A)| = 2^(2^(2^(2^...))) = |A|. That is, powerset of A and A are the same sizes.

  25. Re:I'm always amazed... on Evidence of the Missing Link Found? · · Score: 1

    once you start certain chains of molecules, the order in which they bond is far from uniformly distributed. It strongly favors certain patterns

    But as long as there are variations, such as orientation and symmetry, to the way these molecules are bonded, you still have an exponential search space.

    I can't see why you would dismiss intellectual design so easily.