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        <title>BULETINUL INSTITUTULUI POLITEHNIC DIN IAȘI. Secția Matematica. Mecanică Teoretică. Fizică Feed</title>
        <link>https://sciendo.com/journal/BIPMF</link>
        <description>Sciendo RSS Feed for BULETINUL INSTITUTULUI POLITEHNIC DIN IAȘI. Secția Matematica. Mecanică Teoretică. Fizică</description>
        <lastBuildDate>Sun, 10 May 2026 13:18:18 GMT</lastBuildDate>
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            <title>BULETINUL INSTITUTULUI POLITEHNIC DIN IAȘI. Secția Matematica. Mecanică Teoretică. Fizică Feed</title>
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            <link>https://sciendo.com/journal/BIPMF</link>
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        <copyright>All rights reserved 2026, Gheorghe Asachi Technical University of Iasi</copyright>
        <item>
            <title><![CDATA[The Method of Reducing Distortions in the Radar Image of the Earth’s Surface Caused by Changes in the Course of the Movement of the Synthetic Aperture Radar]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2025-0003</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2025-0003</guid>
            <pubDate>Sat, 06 Dec 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

The article addresses distortions in synthetic aperture radar (SAR) images caused by the non-linear motion of the radar platform. Such motion, often due to navigation errors, environmental factors, or maneuvering, introduces Doppler frequency components into the received signal. These distortions lead to reduced image intensity and multiple displaced replicas of objects along the flight path. Analytical and simulation results show intensity can drop to 45% of the undistorted value, with object replicas appearing at regular intervals related to Doppler shift and system parameters. To counter this, the paper proposes a method that estimates Doppler components and applies a time-dependent phase correction via numerical integration. This correction is implemented before standard SAR processing and does not require precise knowledge of the platform’s trajectory. The study has a predominantly theoretical character, and the validation of the proposed method was carried out exclusively through numerical simulations without the use of real experimental data. Simulations show that with up to 20% estimation error, image intensity is restored to 85% and artifacts are suppressed. The method is efficient, practical, and compatible with existing SAR systems.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Biomechanics-Driven Development of Prosthetic Fingers: A Two-Phalanx Approach]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2025-0002</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2025-0002</guid>
            <pubDate>Sat, 18 Oct 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

This study presents a biomechanics-driven approach to develop two-phalanx prosthetic fingers replicating essential human finger motions. A detailed biomechanical analysis of joint trajectories, anatomical constraints, and functional coordination for tasks like grasping identifies key motion features to guide design. Two underactuated prosthetic finger mechanisms are proposed, balancing anatomical realism with structural simplicity. Each employs mechanical couplings and passive elements to achieve coordinated phalanx flexion and extension using minimal actuation, enhancing manufacturability and integration into upper limb prostheses. Kinematic modelling using Denavit–Hartenberg parameters in MATLAB generates motion trajectories and assesses fingertip path accuracy under various actuation conditions. Integrated biomechanical constraints ensure realistic motion ranges and joint coordination. Comparison with natural finger behaviour shows both mechanisms closely approximate intended motion patterns, delivering satisfactory trajectory fidelity, smoothness, repeatability, and reproducibility. These results demonstrate the effectiveness of biomechanics-informed design and hybrid kinematic modelling for practical, anatomically relevant prosthetic fingers and potential for customization of prosthetics.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Some Physical Implications of the Vectors of Zero Norm]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2025-0001</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2025-0001</guid>
            <pubDate>Sun, 04 May 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

Using the geometry of the zero-norm vectors, it is shown that at the cosmological scale resolution, the removing of the singularity of the Schwarzchild metric implies, based on the Kruskal coordinates, Rindler-type dynamics, while at the microscopic scale resolution it implies the Yamamoto form of the spin coordinates and implicitly an egalitarian relationship of uncertainly relationships.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Vortex-Bubble System as a Spin Acoustic Particle Model]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0009</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0009</guid>
            <pubDate>Fri, 21 Mar 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

A vortices-bubble system may be depicted by some features which may lead to infer its acoustic charge and its spin- angular momentum. We study the dynamics of this system within the framework of fluid physics and with the help of Maxwell’s hydrodynamic equations. Since we will adopt an approach of a fluid without viscosity and without gravity, then the fluid is in steady state if also we will neglect the acoustic radiation. When we expressed the energy (the kinetic and potential energy) of the vortex-bubble system we found out that the state of bubble which is captured in the core of the vortex is more stable than it is out of the core. For the above allegations we consider that this system, namely a vortex-bubble system, is a good approach for an acoustic particle with charge and spin angular momentum. This system owns to the Acoustic World.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Compatibility of Fluid Maxwell Equations with Interactions Between Oscillating Bubbles]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0010</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0010</guid>
            <pubDate>Fri, 21 Mar 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

The result of this paper is the derivation of the expression for the interaction force between two pulsating/oscillating bubbles (the secondary Bjerknes force). This is done by expressing the force using the hydrodynamic Maxwell equations for a fluid. These subsequent equations were written for the quantities: velocity, pressure and density as deviations from steady state. Also, as it will show in the following rows, we found the expressions of the acoustic charge and of the acoustic intensity. Our results may facilitate an approach for the interaction of two vortices and for the interaction of a bubble with a vortex. This approach leads to a model for an acoustic charged particle which has internal angular momentum.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Motion Dynamic Scenarios in the Scale Relativity Theory]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0007</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0007</guid>
            <pubDate>Fri, 21 Mar 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

Assuming that any complex system, both structural and functional, can be assimilated to a mathematical object of multifractal type, it is shown that its dynamics can be described by multifractal curves. In such a framework, based on the Multifractal Theory of Motion, the Schrödinger multifractal and the Madelung multifractal scenarios become not only compatible, but also complementary in the dynamic descriptions.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[On the Rindler’s Type Motions by Means of a Variational Principle]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0008</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0008</guid>
            <pubDate>Fri, 21 Mar 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

Using a variational principle of Misner’s type, based on a Lobachevsky plane metric treated as a Cayleian metric of the Euclidean plane, Rindler-type motions are analyzed. Within this framework and taking into account the principle of the independence of the simultaneous actions of the fields at a point, it can be replaced by the invariance of the field effects under a certain group and thus a theory of gravity can be formulated to eliminate the intrinsic inconsistencies present in the existing theory.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Comparative Study of Dissipation Factor of Young and Mature Bitter Leaf (Vernonia Amygdalina) based on Location]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0006</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0006</guid>
            <pubDate>Wed, 05 Feb 2025 00:00:00 GMT</pubDate>
            <description><![CDATA[

The use of Schering Bridge arrangement in combination with function generator and oscilloscope allows for precise measurement of heat dissipation in plant materials. This study aims to determine and compare the heat dissipation properties of young bitter leaf (YBL) and mature bitter leaf (MBL) samples obtained from two different locations. Measurements were conducted on ten fresh leaf samples per category from each location. Results indicated that for samples from the first location, the dissipation factors for YBL and MBL were (2.076 ± 0.010) and (3.231 ± 0.013) respectively, while from the second location, the values were (3.231 ± 0.013) and (3.233 ± 0.015) respectively. The data suggest that while the geographical location does not significantly influence the heat dissipation of bitter leaf (Vernonia amygdalina), the age of the leaves does, with YBL exhibiting a higher capacity to withstand elevated temperatures compared to MBL under identical storage conditions. This study provides insight into the thermal properties of bitter leaf, contributing to broader research on plant thermoregulation. The novelty of this work lies in its demonstration that leaf age, rather than location, is a determinant factor in heat dissipation.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Phenomena in Bubbles Cluster]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0005</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0005</guid>
            <pubDate>Sat, 06 Jul 2024 00:00:00 GMT</pubDate>
            <description><![CDATA[

In this paper, we continue to demonstrate the analogy between the acoustic world and the electromagnetic world. In the paper, we derive the expressions for: the electro-acoustic force between the bubbles in the cluster and an outer bubble, the gravito-acoustic forces between the bubbles in the cluster and between the cluster and an outer bubble, the temperature corresponding to the translational motion of the bubbles in the cluster (acoustic temperature) and the average acoustic radiation pressure. The most important result is the demonstration of the fact that the modulus of the average pressure of the acoustic radiation around a bubble is equal to the energy density of the electro-acoustic field, Eq. (10). These densities are the oscillation energy densities of the liquid around the bubble that are involved in the interaction phenomenon between two oscillating/pulsating bubbles. We have also demonstrated that the gravito - acoustic forces, at resonance, between the bubbles in the cluster, generated by the absorption of energy in the bubbles, are proportional to the square of the virtual masses of the bubbles, Eqs. (29) and (30).
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Quantitative Analysis of Secondary Bjerknes Forces in Various Liquids]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0004</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0004</guid>
            <pubDate>Sat, 06 Jul 2024 00:00:00 GMT</pubDate>
            <description><![CDATA[

Evaluating numerically the interaction forces between two free bubbles, under the action of a background of random acoustic radiation, we highlight the contributions of coefficients βs0 and βa0 = βu0 + βth0 to the magnitude of these forces. The quantitative study of the forces is done for several fluids, as different as possible in terms of properties: water, mercury, liquid helium, and superfluid helium. These forces are evaluated, for different radii of the oscillating bubbles, R0 = ⎡10−1 − 10−10⏋ m, that the scattering–absorption forces and the scattering–scattering forces are close in magnitude. For water, mercury and liquid helium, the force ratio is in the range fa ∈ (10−3 −1). For superfluid helium, the forces change direction, oscillating, and the ratio of the forces is much less than one, |fa|  1.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Short Blizzard Episode in the Northeastern Part of Romania, in the Second Decade of November 2023]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0003</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0003</guid>
            <pubDate>Tue, 28 May 2024 00:00:00 GMT</pubDate>
            <description><![CDATA[

Severe weather phenomena are those meteorological phenomena that can temporarily become dangerous for the population, by threatening its safety or can cause material damage in a certain area. In order for the authorities and the population to be notified in time, meteorological warnings are issued. Therefore, issuing a warning will be taken into account according to the degree of severity of the forecasted meteorological phenomenon and will take into account its extent, how it will evolve and the degree of vulnerability of the regions to be affected. For this purpose, warning thresholds have been established for certain meteorological phenomena that can become dangerous, and based on this, color codes have been established, which gradually show the dangerousness of the phenomena that are about to occur. In the cold season, the blizzard is part of the category of dangerous meteorological phenomena, even more so when they are early or late, in the months of November or April. If the late ones are more frequent, (in the last 10 years there were 2 blizzard events, in 2017 and 2023), the early ones have an even lower frequency, and sometimes it can be a derivative of this phenomenon, because they are not met all the blizzard conditions. This study analyzes a phenomenon that took place in the second decade of November 2023 in the region of Moldova and which was associated with the blizzard phenomenon.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Heat Waves Analysis of 2023 Summer in Eastern Part of Romania and Atmospheric Instability Events Which Succeeded Between Them]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0002</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0002</guid>
            <pubDate>Tue, 28 May 2024 00:00:00 GMT</pubDate>
            <description><![CDATA[

The purpose of this paper is a general climatic characterization of the 2023 summer in the region of Moldavia, in eastern part of Romania, but with focus on the analysis of the context in which the most intense tropical air advections occurred in this region. The most significant and lasting tropical air waves were in July and August. From a thermal point of view, June had only one interval in which the maximum temperatures exceeded, for 3 consecutive days, the threshold of 30ºC (between 22nd and 24th of June). Instead, in July there were three intervals in which the maximum temperature exceeded this threshold, for more than 3 days in a row (between 01st - 06th, 15th - 22nd, 24th - 26th of July), and August had the longest such intervals (between 03rd – 06th, 13th – 29th of August). Also, in August, there were four consecutive days with maximum temperatures that exceeded the heat wave threshold (26th -29th of August). Without achieving new absolute temperature records (the highest maximum temperature in this interval being 39˚C at the Iași meteorological station, on August 28th), the last heat wave was notable in terms of duration of manifestation. Considering the definition given by the World Meteorological Organization (WMO) in 2020, according to which heat waves are considered those periods of time that are unusually warm in relation to multi-year averages and that last more than 2 consecutive days, we can frame the tropical air advection of July and August in the category of heat waves.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[GPGPU Programming for Dipolar Field Calculation]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2024-0001</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2024-0001</guid>
            <pubDate>Sat, 27 Jan 2024 00:00:00 GMT</pubDate>
            <description><![CDATA[

Accelerating computational processes is paramount in numerical infrastructure development, particularly in applications such as the finite element method (FEM) and extensive calculations for simulating 3D processes in materials. In this work, we introduce a novel technique for computing the magnetostatic field of an ellipsoid particle, leveraging CUDA on a graphical card for parallel processing. The implementation on a GPU resulted in a remarkable 20-fold improvement in calculation speed. This achievement not only expedites research tasks, but also enables the exploration of larger and more intricate simulations, facilitating quicker model refinements and deeper insights into material behaviours under various conditions. The utilization of GPU computing aligns with the broader trend in scientific research and engineering, offering a versatile solution for diverse computational challenges beyond this specific task of magnetism. Overall, our work contributes to the ongoing effort to harness high-performance computing (HPC) technologies for accelerated and more efficient simulations in materials science and related fields.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Hypercomplex Quaternions and Higher-Order Analysis of Spatial Kinematic Chains]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2023-0002</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2023-0002</guid>
            <pubDate>Fri, 29 Dec 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

This paper introduces a novel computational method for analyzing the higher-order acceleration field of spatial kinematics chains. The method is based on vector and quaternionic calculus, as well as dual and multidual algebra. A closed-form coordinate-free solution generated by the morphism between the Lie group of rigid body displacements and the unit multidual quaternions is presented. Presented solution is used for higher-order kinematics investigation of lower-pair serial chains. Additionally, a general method for studying the vector field of arbitrary higher-order accelerations is discribed. The method utilizes the “automatic differentiation” feature of multidual and hyper-multidual functions to obtain the higher-order derivative of a rigid body pose without need in further differentiation of the body pose regarding time. Also is proved that all information regarding the properties of the distribution of higher-order accelerations is contained in the specified unit hyper-multidual quaternion.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Steady State Solutions of MHD Stokes Problems for Generalized Burgers Fluids Through Porous Media]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2023-0005</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2023-0005</guid>
            <pubDate>Fri, 29 Dec 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

Stokes’ problems for the incompressible generalized Burgers fluids are investigated when magnetic and porous effects are taken into account. Non-dimensional exact expressions are provided for the components of velocity, non-trivial shear stress and Darcy’s resistance. They can immediately be particularized to recover similar solutions for the viscous, second grade, Maxwell, Oldroyd-B and Burgers fluids. For their validation, the solutions are given in two forms whose equivalence has been proved in a graphical manner. The results, which correct previous solutions from the existing literature, can be useful for the experimental researchers who want to know the need time to touch the steady state and to bring to light the influence of porous medium and magnetic field on the flow resistance of the fluid. Finally, by graphical illustrations, it was shown that the flow resistance of fluid enhances through porous media and decreases when a magnetic field is present.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[High-Order Derivatives of Serial Manipulator Jacobians Using Multidual Differentiation Transform]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2023-0001</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2023-0001</guid>
            <pubDate>Fri, 29 Dec 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

The use of robots is continuously growing, from heavy-duty industries to nanotechnology. Exact multilink robot end effector control is required to withstand this tendency in modern robotics. Mapping between joint variables in joint-space coordinate and end effector configuration in task-space coordinate are provided by serial manipulator kinematics. A computation of higher-order Jacobian matrix derivatives is required for accurate trajectory tracking. With conventional numerical derivation, only approximate results can be obtained. Still, the computation of high-order derivatives of multi-DoF manipulators with high accuracy requires long time intervals and it is difficult. This paper investigates a novel derivation method for a multilink robot Jacobian. According to this method, an exact value of higher-order acceleration can be obtained using a multidual differentiation transform. Multidual functions for sine and cosine will be used to get the exact value of acceleration, jerk, and hyper-jerk (jounce) expressions, commonly used for accurate trajectory-tracking.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Physical Principles in Revealing the Working Mechanisms of Brain. Part IV]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2023-0003</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2023-0003</guid>
            <pubDate>Fri, 29 Dec 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

The living brain is physically modeled as a universe, equivalent, in a way, to the physical universe we live in. While in the case of the physical universe the gravitation prevails, in the brain universe, if we may, the electricity prevails, but the mathematical description we provide is essentially the same in both cases. What is imperiously necessary in this approach is, first, a metric description of matter, then, of course, the physical interpretation of this description. These issues were treated, but only in their believed essentials, in the previous three instalments of the present work. The object of the present episode of the work is a classical space image of the matter. This image is worked out here having in the background the idea of a necessary physical connection between the matter of a universe and its fundamental physical structure. The matter can be characterized ‘optically’ as a Maxwell fish-eye, while the fundamental physical structure must be a dipole. Both these concepts are universal.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Physical Principles in Revealing the Working Mechanisms of Brain. Part V]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2023-0004</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2023-0004</guid>
            <pubDate>Fri, 29 Dec 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

Still after the right concept of universe, we extract from the Einstein-de Sitter debate presented previously the physical characteristics of a continuum charge background to serve for the description of brain. This time we settle for the cosmological metric of the universe, which appear to be well suited for the brain, and the content in events of a generic universe serving for the definition of events in the brain. The hologram is also defined as a general characteristic of a universe, in order to serve in describing the process of memory. The idea of coherence is used, in order to define the frequency in an invariant way.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[“Holographic” Type Implementations in the Description of Drug Release Dynamics]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2022-0019</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2022-0019</guid>
            <pubDate>Fri, 30 Jun 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

The dynamics of drug release from polymeric structures are presented in the context of the Scale Relativity Theory, by using a fractal Fokker-Planck type equation, isometry by inversion of fractal coordinates (spatial and temporal coordinates of fractal type) is shown, which can describe different nonlinear processes implied in drug release dynamics.
]]></description>
            <category>ARTICLE</category>
        </item>
        <item>
            <title><![CDATA[Towards Drug Release Dynamics from a Multifractal Perspective of Motion]]></title>
            <link>https://sciendo.com/article/10.2478/bipmf-2022-0020</link>
            <guid>https://sciendo.com/article/10.2478/bipmf-2022-0020</guid>
            <pubDate>Fri, 30 Jun 2023 00:00:00 GMT</pubDate>
            <description><![CDATA[

A new mathematical method in the drug release dynamics is proposed using Scale Relativity Theory. Our method is completely different than the standard one, because the variables through which we can describe the release dynamics are non-differentiable mathematical functions (i.e. mathematicals functions both dependent of spatial and time coordinates, and also of scale resolutions). In such context, the scale resolution is correlated with drug release degree so that various drug release regimes can be highlighted (gradual drug release, saturation, decay of polymer matrix etc.).
]]></description>
            <category>ARTICLE</category>
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