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Topic Review
SilverStripe
SilverStripe is a free and open source Content Management System (CMS) and Framework for creating and maintaining websites and web applications. It provides an out of the box web-based administration panel that enables users to make modifications to parts of the website, which includes a WYSIWYG website editor. The core of the software is SilverStripe Framework, a PHP Web application framework. SilverStripe is released under the terms of the BSD License.
  • 476
  • 18 Oct 2022
Topic Review
Lie's Theorem
In mathematics, specifically the theory of Lie algebras, Lie's theorem states that, over an algebraically closed field of characteristic zero, if [math]\displaystyle{ \pi: \mathfrak{g} \to \mathfrak{gl}(V) }[/math] is a finite-dimensional representation of a solvable Lie algebra, then [math]\displaystyle{ \pi(\mathfrak{g}) }[/math] stabilizes a flag [math]\displaystyle{ V = V_0 \supset V_1 \supset \cdots \supset V_n = 0, \operatorname{codim} V_i = i }[/math]; "stabilizes" means [math]\displaystyle{ \pi(X) V_i \subset V_i }[/math] for each [math]\displaystyle{ X \in \mathfrak{g} }[/math] and i. Put in another way, the theorem says there is a basis for V such that all linear transformations in [math]\displaystyle{ \pi(\mathfrak{g}) }[/math] are represented by upper triangular matrices. This is a generalization of the result of Frobenius that commuting matrices are simultaneously upper triangularizable, as commuting matrices form an abelian Lie algebra, which is a fortiori solvable. A consequence of Lie's theorem is that any finite dimensional solvable Lie algebra over a field of characteristic 0 has a nilpotent derived algebra (see #Consequences). Also, to each flag in a finite-dimensional vector space V, there correspond a Borel subalgebra (that consist of linear transformations stabilizing the flag); thus, the theorem says that [math]\displaystyle{ \pi(\mathfrak{g}) }[/math] is contained in some Borel subalgebra of [math]\displaystyle{ \mathfrak{gl}(V) }[/math].
  • 476
  • 25 Oct 2022
Topic Review
Hattendorf's Theorem
Hattendorff's Theorem, attributed to K. Hattendorff (1868), is a theorem in actuarial science that describes the allocation of the variance or risk of the loss random variable over the lifetime of an actuarial reserve. In other words, Hattendorff's theorem demonstrates that the variation in the present value of the loss of an issued insurance policy can be allocated to the future years during which the insured is still alive. This, in turn, facilitates the management of risk prevalent in such insurance contracts over short periods of time.
  • 476
  • 02 Nov 2022
Topic Review
Infrared and Visible Image Fusion Technologies
Infrared and visible image fusion is to combine the information of thermal radiation and detailed texture from the two images into one informative fused image. Deep learning methods have been widely applied in this task; however, those methods usually fuse multiple extracted features with the same fusion strategy, which ignores the differences in the representation of these features, resulting in the loss of information in the fusion process. Infrared and visible image fusion techniques can be divided into two categories: traditional methods and deep learning-based methods. Traditional methods have been proposed for the fusion of pixel-level or fixed features. 
  • 476
  • 03 Feb 2023
Topic Review
Anonymous Web Browsing
Anonymous web browsing refers to the utilization of the World Wide Web that hides a user's personally identifiable information from websites visited. The current popular application for anonymous browsing is the Tor Browser.
  • 474
  • 28 Sep 2022
Topic Review
Petya (Malware)
Petya is a family of encrypting malware that was first discovered in 2016. The malware targets Microsoft Windows–based systems, infecting the master boot record to execute a payload that encrypts a hard drive's file system table and prevents Windows from booting. It subsequently demands that the user make a payment in Bitcoin in order to regain access to the system. The Petya malware had infected millions of people during its first year of its release. The maker of the Petya malware was arrested and fined.[citation needed] Variants of Petya were first seen in March 2016, which propagated via infected e-mail attachments. In June 2017, a new variant of Petya was used for a global cyberattack, primarily targeting Ukraine . The new variant propagates via the EternalBlue exploit, which is generally believed to have been developed by the United States . National Security Agency (NSA), and was used earlier in the year by the WannaCry ransomware. Kaspersky Lab referred to this new version as NotPetya to distinguish it from the 2016 variants, due to these differences in operation. In addition, although it purports to be ransomware, this variant was modified so that it is unable to actually revert its own changes. The NotPetya attacks have been blamed on the Russian government, specifically the Sandworm hacking group within the GRU Russian military intelligence organization, by security researchers, Google, and several governments.
  • 474
  • 17 Nov 2022
Topic Review
Nanofluids Formulation, Characterization, and Stability
Nanofluids (NFs) synthesized via the suspension of diverse nanoparticles into conventional thermal fluids are known to exhibit better thermal, optical, tribological, and convective properties, photothermal conversion, and heat transfer performance in comparison with traditional thermal fluids. Stability is pivotal to NF preparation, properties, performance, and application. 
  • 474
  • 31 Jan 2023
Topic Review
Cybersecurity in Smart Cities
Smart technologies, such as the Internet of Things (IoT), cloud computing, and artificial intelligence (AI), are being adopted in cities and transforming them into smart cities. In smart cities, various network technologies, such as the Internet and IoT, are combined to exchange real-time information, making the everyday lives of their residents more convenient.  Cybersecurity for smart cities includes a combination of technologies that have emerged to address the highly complex challenges of insecure devices and networks, which can lead to unbounded attacks. 
  • 474
  • 17 Apr 2023
Topic Review
Human–Autonomous Taxis Interactions
With the increasing deployment of autonomous taxis in different cities around the world, recent studies have stressed the importance of developing new methods, models and tools for intuitive human–autonomous taxis interactions (HATIs). Street hailing is one example, where passengers would hail an autonomous taxi by simply waving a hand, exactly like they do for manned taxis.
  • 474
  • 30 May 2023
Topic Review
Automatic Speech Recognition in Portuguese Language
Automatic speech recognition (ASR), commonly known as speech-to-text, is the process of transcribing audio recordings into text, i.e., transforming speech into the respective sequence of words. 
  • 474
  • 15 Jun 2023
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