This paper explains why the critical line sits at the real part equal to one-half by treating it as an intrinsic boundary of a reparametrized complex plane (“<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi></mrow></semantics></math></inline-formula>-space”), not a mere artifact of functional symmetry. In <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi></mrow></semantics></math></inline-formula>-space the real part is defined by a geometric-series map that gives rise to a rulebook for admissible analytic operations. Within this setting we rederive the classical toolkit—the eta–zeta relation, Gamma reflection and duplication, theta–Mellin identity, functional equation, and the completed zeta—without importing analytic continuation from the usual <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>s</mi></mrow></semantics></math></inline-formula>-variable. We show that access to the left half-plane occurs entirely through formulas written on the right, with boundary matching only along the line with the real part equal to one-half. A global Hadamard product confirms the consistency and fixed location of this boundary, and a holomorphic change of variables transports these conclusions into the classical setting.
Efficient target detection in hyperspectral images faces significant deployment challenges on resource-constrained edge platforms due to the large data volume and high computational complexity of detection algorithms. This paper proposes a CEM target detection method based on 1D-CNN feature dimensionality reduction. A lightweight 1D-CNN reduces spectral dimensions from <i>L</i> bands to 16 features, decreasing the core matrix inversion complexity from <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>O</mi><mo>(</mo><msup><mi>L</mi><mn>3</mn></msup><mo>)</mo></mrow></semantics></math></inline-formula> to <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>O</mi><mo>(</mo><msup><mn>16</mn><mn>3</mn></msup><mo>)</mo></mrow></semantics></math></inline-formula>. Unlike PCA-based dimensionality reduction requiring online eigenvalue decomposition, the proposed approach employs fixed pre-trained weights with simple convolution operations, enabling high parallelizability for FPGA implementation. A Zynq-based PS + PL collaborative acceleration scheme is designed, deploying CNN on the PL side through RTL implementation and CEM on the PS side using double-precision floating-point computation. Experimental validation on multiple hyperspectral datasets demonstrates that the proposed method achieves an AUC of 0.9953 with less than 1% difference compared to traditional CEM, processes 40,000 pixels in approximately 10.8 s, and consumes only 2.067 W, making it suitable for power-sensitive edge applications such as UAV reconnaissance and satellite on-board processing. The system achieves a processing rate of 3704 pixels/s.
In this work, Noether symmetries and conserved quantities of a non-standard Birkhoffian system based on the Caputo <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mo>Δ</mo></semantics></math></inline-formula> Pfaff–Birkhoff principle on time scales are studied. Firstly, equations of motion for Caputo <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mo>Δ</mo></semantics></math></inline-formula> non-standard Birkhoffian systems are set up from Caputo <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mo>Δ</mo></semantics></math></inline-formula> variational principle. Secondly, invariance of Caputo non-standard Pfaff action on time scales is demonstrated, thus giving rise to Noether symmetry criterions which establish Noether’s theorems for the corresponding system. The validity of the methods and results presented in the paper is illustrated by means of examples provided at the end of the article.
From the perspective of magnetohydrodynamics (MHD), the heat transfer properties of Maxwell fluids under MHD conditions with modified dynamic viscosity present complex challenges in numerical simulations. In this paper, we develop a time-fractional coupled model to characterize the heat transfer and MHD flow of Maxwell fluid with consideration of the Hall effect and Joule heating effect and incorporating a modified dynamic viscosity. The fractional coupled model is numerically solved based on the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>L</mi><mn>1</mn></mrow></semantics></math></inline-formula>-algorithm and the spectral collocation method. We introduce a novel approach that integrates advanced algorithms with a fully discrete scheme, focusing particularly on the computational cost. Leveraging this approach, we aim to significantly enhance computational efficiency while ensuring accurate representation of the underlying physics. Through comprehensive numerical experiments, we explain the thermodynamic behavior in the MHD flow process and extensively examine the impact of various critical parameters on both MHD flow and heat transfer. We establish an analytical framework for the MHD flow and heat transfer processes, further investigate the influence of magnetic fields on heat transfer processes, and elucidate the mechanical behavior of fractional Maxwell fluids.
Low-light images are prevalent in intelligent monitoring and many other applications, with low brightness hindering further processing. Although low-light image enhancement can reduce the influence of such problems, current methods often involve a complex network structure or many iterations, which are not conducive to their efficiency. This paper proposes a Zero-Reference Camera Response Network using a camera response model to achieve efficient enhancement for arbitrary low-light images. A double-layer parameter-generating network with a streamlined structure is established to extract the exposure ratio <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="bold">K</mi></semantics></math></inline-formula> from the radiation map, which is obtained by inverting the input through a camera response function. Then, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="bold">K</mi></semantics></math></inline-formula> is used as the parameter of a brightness transformation function for one transformation on the low-light image to realize enhancement. In addition, a contrast-preserving brightness loss and an edge-preserving smoothness loss are designed without the requirement for references from the dataset. Both can further retain some key information in the inputs to improve precision. The enhancement is simplified and can reach more than twice the speed of similar methods. Extensive experiments on several LLIE datasets and the DARK FACE face detection dataset fully demonstrate our method’s advantages, both subjectively and objectively.
Sándor Frey, Judit Fogasy, Krisztina Perger
et al.
The prominent radio quasar PKS 2215+020 (J2217+0220) was once labelled as a new laboratory for core–jet physics at redshift <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi><mo>=</mo><mn>3.572</mn></mrow></semantics></math></inline-formula> because of its exceptionally extended jet structure traceable with very long baseline interferometric (VLBI) observations up to a ∼600 pc projected distance from the compact core and a hint of an arcsec-scale radio and an X-ray jet. While the presence of an X-ray jet could not be confirmed later, this active galactic nucleus is still unique at high redshift with its long VLBI jet. Here, we analyse archival multi-epoch VLBI imaging data at five frequency bands from <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>1.7</mn></mrow></semantics></math></inline-formula> to <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>15.4</mn></mrow></semantics></math></inline-formula> GHz covering a period of more than 25 years from 1995 to 2020. We constrain apparent proper motions of jet components in PKS 2215+020 for the first time. Brightness distribution modeling at 8 GHz reveals a nearly <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>0.02</mn></mrow></semantics></math></inline-formula> mas yr<sup>−1</sup> proper motion (moderately superluminal with apparently two times the speed of light), and provides <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>δ</mi><mo>=</mo><mn>11.5</mn></mrow></semantics></math></inline-formula> for the Doppler-boosting factor in the inner relativistic jet that is inclined within <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mn>2</mn><mo>∘</mo></msup></semantics></math></inline-formula> to the line of sight and has a <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi mathvariant="sans-serif">Γ</mi><mo>=</mo><mn>6</mn></mrow></semantics></math></inline-formula> bulk Lorentz factor. These values qualify PKS 2215+020 as a blazar, with rather typical jet properties in a small sample of only about 20 objects at <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi><mo>></mo><mn>3.5</mn></mrow></semantics></math></inline-formula> that have similar measurements to date. According to the 2-GHz VLBI data, the diffuse and extended outer emission feature at ∼60 mas from the core, probably a place where the jet interacts with and decelerated by the ambient galactic medium, is consistent with being stationary, albeit slow motion cannot be excluded based on the presently available data.
Yasushi Muraki, Shoichi Shibata, Hisanori Takamaru
et al.
Muons produced by cosmic rays above the atmosphere provide valuable information on the intensity of cosmic rays and variations in the upper atmosphere. Since 1970, the Nagoya University Cosmic Ray Laboratory has been observing the muon intensity using a multi-directional cosmic ray telescope with two layers of 36 plastic scintillators of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>1</mn><mspace width="4pt"></mspace><msup><mi mathvariant="normal">m</mi><mn>2</mn></msup></mrow></semantics></math></inline-formula> each, which measure the muon intensity in different incident directions. The energy of an incident proton that produces a muon incident from a vertical direction is over 11.5 GV. This paper analyzes vertical muon intensities obtained over 48 years from 1970 to 2018 using methods that differ from the East–West method. As a result, a new periodicity of (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>125</mn><mo>±</mo><mn>45</mn></mrow></semantics></math></inline-formula>) days and a new periodicity of (4–16) days were found. The latter appears only in winter time, so it may be caused by a synoptic-scale disturbance associated with the arrival of the Siberian cold air mass. On the other hand, the former periodicity may be related to solar dynamo activity. In 1984, the Solar Maximum Mission’s Gamma Ray Spectrometers reported a periodicity of about (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>154</mn><mo>±</mo><mn>10</mn></mrow></semantics></math></inline-formula>) days in the flux of solar gamma rays. The (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>125</mn><mo>±</mo><mn>45</mn></mrow></semantics></math></inline-formula>)-day periodicity found here is most likely related to solar dynamo activity, since the intensity of cosmic rays around 11.5 GV is affected by the magnetic field induced by the Sun. However, this (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>125</mn><mo>±</mo><mn>45</mn></mrow></semantics></math></inline-formula>)-day periodicity differs from the report measured by the GRS instrument in a point that it also appears during periods of low solar activity. Furthermore, it has not appeared often during lower solar activity since 1992. This information is important for future investigation of the origin of this periodicity.
In this paper, a Banyan network with high parallelism and nonlinearity is used for the first time in image encryption to ensure high complexity and randomness in a cipher image. To begin, we propose a new 1-D chaotic system (1-DSCM) which improves the chaotic behavior and control parameters’ structure of the sin map. Then, based on 1-DSCM, a Banyan network, and SHA-256 hash function, a novel image encryption algorithm is conducted. Firstly, a parameter is calculated using SHA-256 hash function and then employed to preprocess the plaintext image to guarantee high plaintext sensitivity. Secondly, a row–column permutation operation is performed to gain the scrambled image. Finally, based on the characteristic of DNA encoding, a novel DNA mapping is constructed using an <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>N</mi><mo>=</mo><mn>4</mn></mrow></semantics></math></inline-formula> Banyan network and is used to diffuse the scrambled image. Simulation results show that the 1-DSCM has excellent performance in chaotic behavior and that our encryption algorithm exhibits strong robustness against various attacks and is suitable for use in modern cryptosystems.
This paper proposes an integrated panoramic sun sensor (IPSS) for the small spherical satellite Q-SAT that has been working in orbit since 2020. IPSS is essentially a set of temperature-compensated photoelectric cells distributed on the spherical surface of Q-SAT. Compared with traditional sun sensors, IPSS has full spherical coverage of 4<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>π</mi></semantics></math></inline-formula> so that the sun vector from any direction can be inversed. The mechatronic design and mathematical model of the proposed IPSS are presented. In-depth error analyses in terms of albedo effect, sampling error, parameter deviation, etc. are carried out. IPSS can provide a sun vector inversion accuracy of 1.5<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mo>∘</mo></msup></semantics></math></inline-formula> where albedo disturbance does not dominate. Simulation results show that the measurement of IPSS together with a COTS magnetometer can support the three-axis attitude determination of satellites in various orbits and can adapt to the seasonal variations of subpolar points. Ground experimental results and on-orbit data have also verified the feasibility and performance of IPSS. Although the panoramic sun sensor is designed for the small spherical Q-SAT, it can also be applied to other satellites with limited power budgets.
Riccardo Castagna, Cristiano Riminesi, Andrea Di Donato
et al.
In this work, we test the effectiveness of using highly transparent holographic phase reflection and transmission volume gratings based on multifunctional acrylates as linear compression and rotation sensors. The gratings are recorded in a holographic mixture based on multi-reticulated acrylate and haloalkanes. To activate the photo-polymerization process, we used a mixture of 6-oxocamphore and rhodamine 6G. The mixture is a simplified version of the mixture used in previous works and shows some interesting features mainly in connection with the different roles played by the rhodamine 6G dye at different writing wavelengths <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>λ</mi></semantics></math></inline-formula> = 532 nm and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>λ</mi></semantics></math></inline-formula> = 460 nm. Regarding reflection gratings, the maximum achieved diffraction efficiency is ≈50% and their use as linear compression sensors produces a shift in the reflection peak of 2 nm. Following the removal of compression, the grating slowly returns to the initial state. Regarding transmission gratings, the maximum achieved diffraction efficiency is ≈45% and they demonstrate very high sensitivity to even small rotations in a free-standing configuration.
The pharmaceutical success of atorvastatin (ATV), a widely employed drug against the “bad” cholesterol (LDL) and cardiovascular diseases, traces back to its ability to scavenge free radicals. Unfortunately, information on its antioxidant properties is missing or unreliable. Here, we report detailed quantum chemical results for ATV and its ortho- and para-hydroxy metabolites (o-ATV, p-ATV) in the methanolic phase. They comprise global reactivity indices, bond order indices, and spin densities as well as all relevant enthalpies of reaction (bond dissociation BDE, ionization IP and electron attachment EA, proton detachment PDE and proton affinity PA, and electron transfer ETE). With these properties in hand, we can provide the first theoretical explanation of the experimental finding that, due to their free radical scavenging activity, ATV hydroxy metabolites rather than the parent ATV, have substantial inhibitory effect on LDL and the like. Surprisingly (because it is contrary to the most cases currently known), we unambiguously found that HAT (direct hydrogen atom transfer) rather than SPLET (sequential proton loss electron transfer) or SET-PT (stepwise electron transfer proton transfer) is the thermodynamically preferred pathway by which o-ATV and p-ATV in methanolic phase can scavenge DPPH<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mo>•</mo></msup></semantics></math></inline-formula> (1,1-diphenyl-2-picrylhydrazyl) radicals. From a quantum chemical perspective, the ATV’s species investigated are surprising because of the nontrivial correlations between bond dissociation energies, bond lengths, bond order indices and pertaining stretching frequencies, which do not fit the framework of naive chemical intuition.
Cristiano Maria Verrelli, Cristian Romagnoli, Roxanne Jackson
et al.
A harmonically self-similar temporal partition, which turns out to be subtly exhibited by elite swimmers at middle distance pace, is formally defined for one of the most technically advanced swimming strokes—the butterfly. This partition relies on the generalized Fibonacci sequence and the golden ratio. Quantitative indices, named <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>ϕ</mi></semantics></math></inline-formula>-bonacci butterfly stroke numbers, are proposed to assess such an aforementioned hidden time-harmonic and self-similar structure. An experimental validation on seven international-level swimmers and two national-level swimmers was included. The results of this paper accordingly extend the previous findings in the literature regarding human walking and running at a comfortable speed and front crawl swimming strokes at a middle/long distance pace.
Spyridon Vossos, Elias Vossos, Christos G. Massouros
This paper shows that gravitational results of general relativity (GR) can be reached by using special relativity (SR) via a SR Lagrangian that derives from the corresponding GR time dilation and vice versa. It also presents a new SR gravitational central scalar generalized potential <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>V</mi><mo>=</mo><mi>V</mi><mo stretchy="false">(</mo><mi>r</mi><mo>,</mo><mover><mi>r</mi><mo>.</mo></mover><mo>,</mo><mover><mi>ϕ</mi><mo>.</mo></mover><mo stretchy="false">)</mo></mrow></semantics></math></inline-formula>, where <i>r</i> is the distance from the center of gravity and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mover><mi>r</mi><mo>.</mo></mover><msub><mo>,</mo><mrow></mrow></msub><mover><mi>ϕ</mi><mo>.</mo></mover></mrow></semantics></math></inline-formula> are the radial and angular velocity, respectively. This is associated with the Schwarzschild GR time dilation from where a SR scalar generalized potential is obtained, which is exactly equivalent to the Schwarzschild metric. Thus, the Precession of Mercury’s Perihelion, the Gravitational Deflection of Light, the Shapiro time delay, the Gravitational Red Shift, etc., are explained with the use of SR only. The techniques used in this paper can be applied to any GR spacetime metric, Teleparallel Gravity, etc., in order to obtain the corresponding SR gravitational scalar generalized potential and vice versa. Thus, the case study of Newtonian Gravitational Potential according to SR leads to the corresponding non-Riemannian metric of GR. Finally, it is shown that the mainstream consideration of the Gravitational Red Shift contains two approximations, which are valid in weak gravitational fields only.
Nuclear and particle physics. Atomic energy. Radioactivity