Spread The Word February 24
Spread The Word August 28
s’ = Result(e, s)asserts that s’ is the situation that results when event e occurs in the situation s. Since there may be many different events that can occur in s, and the theory of the function Result does not say which occurs, the theory is nondeterministic. Having some preconditions for the event to occur, we will get to the formula:
Precond(e, s) → s’ = Result(e, s).McCarthy added a formula Occurs(e, s) to the language that can be used to assert that the event e occurs in situation s. We have:
Occurs(e, s) → (Next(s) = Result(e, s)).Adding occurrence axioms makes a theory more deterministic by specifying that certain events occur in situations satisfying designated conditions. The theory still remains partly non-deterministic, but if there are occurrence axioms specifying what events occur in all the possible situations, then the theory becomes deterministic (i.e. has linear time). We can now give a situation calculus theory for SDFW illustrating the role of a non-deterministic theory in determining what will deterministically happen, i.e. by saying what choice a person or machine will make. In the following formulas, lower case term represents a variable and capitalized term represents a constant. Let us assume that an actor has a choice of just two actions a1 and a2 that may be performed in situation s. It means that event Does(actor, a1) or Does(actor, a2) occurs in situation s according to which of Result(Does(actor, a1), s) or Result(Does(actor, a2), s) that actor prefers. The formulas that declare that an actor will do the preferred action are (1)
Occurs(Does(actor, Choose(actor, a1, a2, s), s), s),
Choose(actor, a1, a2, s) =(2)
if P refers(actor, Result(a1, s), Result(a2, s)).
then a1 else a2.Prefers(actor, s1, s2) means that actor prefers s1 to s2 (and therefore made his choice) and this way it makes the theory determinist. Now let us take a non-deterministic theory of “greedy John”:
Result(A1, S0) = S1,
Result(A2, S0) = S2,
Wealth(John, S1) = $2.0 × 106 ,
Wealth(John, S2) = $1.0 × 106 ,(3)
(∀s s’)(Wealth(John, s) > Wealth(John, s’) → Prefers(John, s, s’).It is obvious that greedy John prefers a situation in which he has greater wealth by making the right action from situation S0 to situation S1. From equations ¹-³ it can be inferred (4)
Occurs(Does(John, A1, S0))Prefers(actor, s1, s2) means that actor prefers s1 to s2 and there were used two actions to keep the formula for Choose as short as possible. This illustrates briefly the role of the non-deterministic theory of Result within a deterministic theory of what occurs. Equation (1) represents the non-deterministic of Result used to asses which action leads to the better situation. Equation (2) represents the deterministic part that indicates which action occurs. McCarthy makes four conclusions: • “1. Effective AI systems, e.g. robots, will require identifying and reasoning about their choices once they get beyond what can be achieved with situation-action rules (i.e. chess programs always have). • The above theory captures the most basic feature of human free will. • Result(a1, s) and Result(a2, s), as they are computed by the agent, are not full states of the world but elements of some theoretical space of approximate situations the agent uses in making its decisions. Part of the problem of building human level AI lies in inventing what kind of entity Result(a, s) shall be taken to be. • Whether a human or an animal uses simple free will in a type of situation is subject to experimental investigation.” We can consider that formulas (¹) and (²) illustrate a person making a choice. Nothing about person knowing it has some choices or preferring situations in which there are available more choices. So, for the situations when we need to take into considerations these phenomena we have to extend SDFW – as a partial theory. The importance of this theory is enormous both in terms of the interest given to the understanding of cognitive processes by man and as an aggregating result of some essential minds of the time who supported McCarthy in its realization. The second algorithm proposal comes from the well-known Alan Turing. One of the pioneers and most prominent promoters of theoretical computer science, Alan Turing was a mathematician, logician, cryptanalyst, philosopher, and British botanist. Perhaps his best-known contribution to the field is the Turing Machine - a mathematical model that has received over time numerous theoretical variants and alternatives as well as practical implementations. To fully understand the context of its creation, it must first be mentioned that in the 1930s, there were no computers, but this did not prevent the scientists of the time from proposing extremely bold theoretical objectives regarding the opening of the application area (i.e., “Halting Problem”). The Turing Machine has the following parts: 1. an infinite roll of tape over which the symbols can be written, deleted and rewritten 2. the head that moves left and right on the tape as the symbols are written/rewritten or deleted (i.e. the head of a Hard Disk Drive) 3. the state register that represents a memory area which stores the state of the machine The machine can read a symbol on the tape at some point, then write a symbol and then reposition the writing head to the left or right. Although it has only implemented these simple routines, we will prove in the following that this model – and therefore, the Turing Machine – provides the theoretical basis for implementing any algorithm in any known language. The table of instructions for use of the machine is presented in the table below.
|Current state||Current symbol||Action||Move||Next state|
|Current state||Current symbol||Action||Move||Next state|
Knowledge Corner August 6
The system was created as an offshoot of the pioneering research into speech synthesis developed by a team that included Paul Breedlove as the lead engineer. Breedlove was the one that came up with the idea of a learning aid for spelling. Breedlove’s plan was to build upon bubble memory, another TI research effort, and as such it involved an impressive technical challenge: the device should be able to speak the spelling word out loud.
The team analyzed several options regarding how to use the new technology and the winner was this 50$ toy idea.With Apple’s introduction of iOS 12 for all their supported mobile devices came a powerful new utility for automation of common tasks called Siri Shortcuts. This new feature can be enabled via third-party developers in their apps, or custom built by users downloading the Shortcuts app from the app store. Once downloaded and installed, the it grants the power of scripting to perform complex tasks on users’ personal devices. Siri Shortcuts can be a useful tool for both users and app developers who wish to enhance the level of interaction users have with their apps. But this access can potentially also be abused by malicious third parties. According to X-Force IRIS research, there are security concerns that should be taken into consideration in using Siri Shortcuts. For instance, Siri Shortcuts can be abused for scareware, a pseudo-ransom campaign trying to trick potential victims into paying a certain a criminal by convincing them their data is in the hands of a remote attacker. Using native shortcut functionality, a script could be created to transmit ransom demands to the device’s owner by using Siri’s voice. To lend more credibility to the scheme, attackers can automate data collection from the device and have it sent back the user’s current physical address, IP address, contents of the clipboard, stored pictures/videos, contact information and more. This data can be displayed to the user to convince them that an attacker can make use of it unless they pay a ransom. To move the user to the ransom payment stage, the shortcut could automatically access the Internet, browsing to a URL that contains payment information via cryptocurrency wallets, and demand that the user pay-up or see their data deleted, or exposed on the Internet. Apple prefers quick access over device security for Siri, which is why the iOS default settings allow Siri to bypass the passcode lock. However, allowing Siri to bypass the passcode lock could allow a thief or hacker to make phone calls, send texts, send e-mails, and access other personal information without having to enter the security code first. There is always a balance that must be struck between security and usability. Users and software developers must choose how much perceived security feature-related inconvenience are they willing to endure in order to keep their devices safe versus how quickly and easily they want to be able to use them. Whether you prefer instant access to Siri without having to enter a passcode is completely up to you. In some cases, while you're in the car, for example, driving safely is more important than data security. So, if you use your iPhone in hands-free mode, keep the default option, allowing the Siri passcode bypass. As the Siri feature becomes further advanced and the amount of data sources it is tapped into increases, the data security risk for the screen lock bypass may also increase. For example, if developers tie Siri into their apps in the future, Siri could provide a hacker with financial information if a Siri-enabled banking app is running and logged in using cached credentials and a hacker asks Siri the right questions.