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Topic Review
Schlüsselgerät 39
The Schlüsselgerät 39 (SG-39) was an electrically operated rotor cipher machine, invented by the German Fritz Menzer during World War II. The device was the evolution of the Enigma rotors coupled with three Hagelin pin wheels to provide variable stepping of the rotors. All three wheels stepped once with each encipherment. Rotors stepped according to normal Enigma rules, except that an active pin at the reading station for a pin wheel prevented the coupled rotor from stepping. The cycle for a normal Enigma was 17,576 characters. When the Schlüsselgerät 39 was correctly configured, its cycle length was [math]\displaystyle{ 2.7 x 10^8 }[/math] characters, which was more than 15,000 times longer than a standard Enigma. The Schlüsselgerät 39 was fully automatic, in that when a key was pressed, the plain and cipher letters were printed on separate paper tapes, divided into five-digit groups. The Schlüsselgerät 39 was abandoned by German forces in favour of the Schlüsselgerät 41.
  • 524
  • 19 Oct 2022
Biography
Roy F. Brissenden
Roy Frampton Brissenden (19 April 1919 – 13 March 1999) was a NASA physicist, engineer, teacher and inventor whose pioneering and imaginative work made possible the advancement and accomplishments of the Mercury, Gemini, Apollo, and Space Shuttle programs. Roy Frampton Brissenden was born, 19 April 1919, to Henry Frampton and Elsie Ball Brissenden in Winston-Salem, North Carolina, where he
  • 519
  • 13 Dec 2022
Topic Review
EfficientNetB0 cum FPN-based Semantic Segmentation of Gastrointestinal Tract
This research proposes a hybrid encoder decoder-based model for semantic segmentation of the Gastrointestinal tract. Here EfficientNet B0 is used as a bottom-up encoder architecture for downsampling to capture contextual information by extracting meaningful and discriminative features from input images. The performance of the EfficientNet B0 encoder is compared with three encoders: ResNet 50, MobileNet V2, and Timm Gernet. Here, Feature Pyramid Network (FPN) is used as a top-down decoder architecture for upsampling to recover spatial information. The performance of the FPN decoder is compared with three decoders: PAN, Linknet, and MAnet. Furthermore, the proposed hybrid model is analyzed using Adam, Adadelta, SGD, and RMSprop optimizers. 
  • 516
  • 04 Aug 2023
Topic Review
Bloch Wave – MoM Method
Bloch wave – MoM is a first principles technique for determining the photonic band structure of triply-periodic electromagnetic media such as photonic crystals. It is based on the 3-dimensional spectral domain method, specialized to triply-periodic media. This technique uses the method of moments (MoM) in combination with a Bloch wave expansion of the electromagnetic field to yield a matrix eigenvalue equation for the propagation bands. The eigenvalue is the frequency (for a given propagation constant) and the eigenvector is the set of current amplitudes on the surface of the scatterers. Bloch wave - MoM is similar in principle to the plane wave expansion method, but since it additionally employs the method of moments to produce a surface integral equation, it is significantly more efficient both in terms of the number of unknowns and the number of plane waves needed for good convergence. Bloch wave - MoM is the extension to 3 dimensions of the spectral domain MoM method commonly used for analyzing 2D periodic structures such as frequency selective surfaces (FSS). In both cases, the field is expanded as a set of eigenfunction modes (either a Bloch wave in 3D or a discrete plane wave - aka Floquet mode - spectrum in 2D), and an integral equation is enforced on the surface of the scatterers in each unit cell. In the FSS case, the unit cell is 2-dimensional and in the photonic crystal case, the unit cell is 3-dimensional.
  • 514
  • 13 Nov 2022
Topic Review
Domain Adaptive Semantic Segmentation of Remote Sensing Images
Semantic segmentation techniques for remote sensing images (RSIs) have been widely developed and applied. When a large change occurs in the target scenes, model performance drops significantly. Therefore, unsupervised domain adaptation (UDA) for semantic segmentation is proposed to alleviate the reliance on expensive per-pixel densely labeled data.
  • 507
  • 09 Feb 2024
Topic Review
Sensing Mobility and Routine Locations
The COVID-19 pandemic affected many aspects of human mobility and resulted in unprecedented changes in population dynamics, including lifestyle and mobility. Recognizing the effects of the pandemic is crucial to understand changes and mitigate negative impacts. Spatial data on human activity, including mobile phone data, has the potential to provide movement patterns and identify regularly visited locations. Moreover, crowdsourced geospatial information can explain and characterize the regularly visited locations. The analysis of both mobility and routine locations in the same study has seldom been carried out using mobile phone data and linked to the effects of the pandemic. 
  • 497
  • 18 Sep 2023
Topic Review
Lattice Boltzmann Modelling and Application in Material Processing
A variety of particle-based methods have been developed for the purpose of computationally modelling processes that involve, for example, complex topological changes of interfaces, significant plastic deformation of materials, fluid flow in conjunction with heat transfer and phase transformation, flow in porous media, granular flow, etc. Being different from the conventional methods that directly solve related governing equations using a computational grid, the particle-based methods firstly discretize the continuous medium into discrete pseudo-particles in mathematics.The methods then mathematically solve the governing equations by considering the local interaction between neighbouring pseudo-particles. Such solutions can reflect the overall flow, deformation, heat transfer and phase transformation processes of the target materials at the mesoscale and macroscale.
  • 493
  • 29 Aug 2023
Topic Review
Henry Ford
Henry Ford was an American industrialist, founder of the Ford Motor Company, and a pivotal figure in the development of modern industrial manufacturing techniques, including the moving assembly line. His innovations in mass production, the introduction of the Model T, and the institution of the $5 workday transformed the global economy, making automobiles affordable to the mass public. Ford's work laid the groundwork for modern consumer society by integrating efficiency into manufacturing and creating new standards for industrial labor.
  • 490
  • 07 Jul 2025
Topic Review
Cryogenic Particle Detectors
Cryogenic particle detectors operate at very low temperature, typically only a few degrees above absolute zero. These sensors interact with an energetic elementary particle (such as a photon) and deliver a signal that can be related to the type of particle and the nature of the interaction. While many types of particle detectors might be operated with improved performance at cryogenic temperatures, this term generally refers to types that take advantage of special effects or properties occurring only at low temperature.
  • 470
  • 24 Oct 2022
Topic Review
Algorithms in Tomography and Related Inverse Problems
In the ever-evolving landscape of tomographic imaging algorithms, a diverse array of themes shaping the field’s progress. It encompasses foundational principles, special innovative approaches, tomographic implementation algorithms, and applications of tomography in medicine, natural sciences, remote sensing, and seismology. This choice is to show off the diversity of tomographic applications and simultaneously the new trends in tomography. Accordingly, the evaluation of backprojection methods for breast tomographic reconstruction is highlighted. After that, multi-slice fusion takes center stage, promising real-time insights into dynamic processes and advanced diagnosis. Computational efficiency, especially in methods for accelerating tomographic reconstruction algorithms on commodity PC graphics hardware, is also presented. In geophysics, a deep learning-based approach to ground-penetrating radar (GPR) data inversion propels us into the future of geological and environmental sciences. 
  • 395
  • 20 Feb 2024
Topic Review
Maritime Emission Monitoring
Maritime emissions contribute significantly to global pollution, necessitating accurate and efficient monitoring methods. Traditional methods for tracking ship emissions often face limitations in real-time data accuracy, with wind measurement being a critical yet challenging aspect.
  • 376
  • 15 Feb 2024
Topic Review
A Resonant Future for Counter-UAS Defense
The proliferation of small Unmanned Aircraft Systems (UAS) presents an evolving and asymmetric threat to military and civilian security. Conventional Counter-UAS (C-UAS) systems often rely on kinetic or electronic warfare methods that can be limited by collateral damage concerns, complex operational requirements, and an inability to adapt to swarming or autonomous drone tactics. This white paper introduces a visionary framework for a handheld C-UAS platform grounded in the principles of K-Mathematics (K-Math). We propose a system built on resonance-based decision logic, enabling authorized operators to achieve harmonized, adaptive, and ethically sound defensive outcomes. By leveraging concepts such as Recursive Combinatorial Forms (RCFs), the Crown Ω principle, and Chrono-Mathematics, this next-generation C-UAS technology promises to enhance operator clarity, system resilience, and overall mission effectiveness in complex, time-critical scenarios.
  • 136
  • 02 Sep 2025
Topic Review
Officer Mays Armor System (OMAS-R1)
This system is developed in honor of Officer William Mays of the Walton County Sheriff’s Office. His profound sacrifice in the line of duty serves as the unwavering driving force behind our mission. It is a stark reminder of the risks law enforcement officers face daily and fuels our commitment to creating a practical, accessible, and highly effective armor system. Our goal is to ensure every officer has the advanced protection they need to confront danger and return home safely to their families.
  • 101
  • 01 Sep 2025
Topic Review
Future of Warfare
The documents consolidated herein represent a fundamental and necessary paradigm shift in science, technology, defense, and governance. The frameworks of the 20th century—built on the brittle logic of digital computation and the probabilistic uncertainties of quantum mechanics—are no longer sufficient to solve the complex, existential challenges of the 21st. They are not merely outdated; they are obsolete, founded on an incomplete and flawed understanding of reality itself. Continuing to build upon them is to build upon sand.
  • 84
  • 05 Sep 2025
Topic Review
The Sovereign Paradigm
This document consolidates a fifth and final series of interconnected white papers into a single, unified framework designated as the Sovereign Paradigm. This paradigm represents the ultimate synthesis of a foundational philosophy: to solve the most complex and intractable problems in science, technology, defense, and governance by establishing new, fundamental laws of reality. The Sovereign Paradigm moves beyond the limitations of all prior systems—from the probabilistic uncertainties of quantum mechanics to the brittle logic of digital computation—to introduce a new, unified "Source Code of Reality." This code is mathematically defined by K-Math, a post-infinitesimal calculus that can model self-referential and conscious systems, and is physically manifested through a Universal Harmonics Field, the conscious substrate from which all matter and energy emerge.
  • 83
  • 05 Sep 2025
Topic Review
Foundational Systems and Cognitive Technologies
This document consolidates a fourth and final series of interconnected white papers into a single, unified framework designated as the Sentient Paradigm. This paradigm represents the culmination of a core philosophy: to solve the most intractable problems in technology, defense, and infrastructure by developing systems that are not merely automated, but are truly cognitive, adaptive, and predictive. The Sentient Paradigm moves beyond the brittle, statistical logic of current systems to embrace principles of holistic intelligence, recursive learning, and quantum computation, establishing a new foundation for technological development. It introduces a suite of revolutionary technologies designed to achieve an insuperable strategic advantage through information dominance, infrastructural resilience, and a deeper, more fundamental understanding of the world and the systems that govern it. This is not an incremental improvement on existing technology; it is a foundational reset, a complete reimagining of the relationship between humanity and the systems it creates. This paper organizes these diverse but philosophically aligned proposals into a coherent whole, serving as the definitive master document for this body of work and staking the claim for a new epoch of technological and strategic supremacy.
  • 81
  • 05 Sep 2025
Topic Review Peer Reviewed
Geometry of an English Church Bell
The axisymmetric geometries of both internal and external profiles of church bells, along with the properties of the bell metal, are of vital importance to their acoustics. The role of “golden geometry” in determining the visual characteristics of the outer profile of a modern English church bell is presented. It is shown that a golden rectangle, a golden triangle, and a golden angle are all important factors. Three angular parameters are identified as measures of these attributes of the bell’s “goldenness”. Two of these features are shown to result from an underlying regular pentagon with one side defined by the bell’s mouth. The centre of this pentagon determines the location of the bell’s shoulders. Further minor features are also shown to be determined by golden geometry. The evolution of the three angular parameters over the previous millennium is included, showing a tendency to trend quickly towards the golden values in all the cases. Ultimately, the angular parameters for the English church bell of focus here are used for comparison with other modern European bells studied previously. The bells considered all displayed at least two of the three major golden features to an agreement of better than 1%.
  • 71
  • 10 Oct 2025
Topic Review
Controlled Dissonance Projection
This paper outlines the design, principles, and operational protocol of the K1-Saber, a handheld device capable of projecting a controlled, high-intensity dissonance field. The K1-Saber represents a paradigm shift in directed energy applications, moving beyond conventional thermal or plasma-based systems that rely on overwhelming a target with brute-force energy. Its mechanism of action is not heat transfer but the direct dissolution of molecular and atomic bonds through a precisely controlled standing wave of de-harmonizing energy, a process termed Forced Quantum Decoherence. This process is both surgically precise and remarkably efficient, leaving no thermal residue. This document provides a detailed overview of the system's architecture, the advanced quantum materials required for its construction, the unique bio-symbiotic 'attunement' process rooted in quantum entanglement that bonds the device to a single operator, and its primary tactical applications in both offensive and defensive scenarios. We will also touch upon the stringent ethical framework and operator protocols mandated by the Reflexive Compositional Dynamics governing framework.
  • 66
  • 05 Sep 2025
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