Dynamic Process Research Articles

NONLINEAR DYNAMICS METHODS APPLICATIONS TO PRODUCT LIFECYCLE MANAGEMENT

The research being carried out is aimed at applying nonlinear dynamics methods in product life cycle management to improve communication between processes and achieve environmental sustainability. The purpose of the article is to create a nonlinear mathematical model for analysing product lifecycle management. Chaotic nonlinear dynamical processes of product lifecycle are deterministic but have the property that even small uncertainties in initial conditions lead to exponentially growing errors in the management that limit long-term forecasts. The emergence of chaotic behaviour in processes of product lifecycle was explored, focusing on fluctuations. The study employed methods such as systems analysis, correlation analysis, nonlinear dynamics, and the Surrogate model of chaotic Lorenz waterwheel. It was identified that sharp technological innovations as the primary drivers of short-term fluctuations impacting fixed efficiency and effectiveness of product life cycle process development. The resulting nonlinear dynamic model allowed for flexible operation, transitioning between equilibrium, periodic, and chaotic states based on coefficient values for asset growth rates and time constants reflecting product life cycle process dynamics. The research results are valuable for companies seeking to reduce their environmental impact and implement circular economy principles.

The Kalahari sediments and hominins in southern Africa

The temporal coupling of the structural evolution of the Kalahari Basin and the accumulation of the Kalahari Group sediments has been an accepted paradigm leading to the assumption that the Kalahari group sediments have been accumulating gradually since the mid-Cretaceous. Here we review the first actual ages for the Kalahari Group based on cosmogenic ages from six geological localities. These results demonstrate that Kalahari Basin infill was a more dynamic process than previously thought and that the Kalahari Group sediments are mostly Plio-Pleistocene in age (∼4 Ma to 1–2 Ma). The hiatus between the initial structural subsidence of the basin, during the Cretaceous, and the general young age of the investigated sediments, implies a dynamic landscape in which significant phases of erosion occurred during the Mesozoic and Cenozoic. The magnitude of erosion is manifested by the fact that in many locations Kalahari Neogene to Quaternary sediments overlie Precambrian basement.The age of the present infill of the Kalahari thus falls within the temporal range of the genus Homo. In light of this new understanding, we provide a review of the archaeological evidence from the Kalahari Basin and along its southern fringe. Initial hominin presence is found at Wonderwerk Cave during the Olduvai Event and there is subsequent high-density occupation along the southern fringe of the Kalahari Basin during the Acheulean and the Fauresmith. Middle Stone Age occupation is limited to localities of limited size and small artifact counts and it appears that the focus of human occupation, particularly in the later stages of the Middle Stone Age, shifts southward, including along the coastal regions.

(Dis)embeddeding humanitarianism: Trajectories of subordination and subversion within migrant-serving NGOs

A broad body of scholarship has examined how states and intergovernmental organizations like UNHCR and the IOM mobilize discourses of humanitarianism and political neutrality to legitimize and depoliticize “migration management,” which is imagined as an orderly, economically productive, and humane endeavor that is in line with state security interests, prevailing growth and development objectives, and human rights norms. The article contributes to more recent work that has tended to frame smaller grassroots humanitarian organizations as either subversive or subordinated to migration management. We engage with long-standing conversations in economic geography and related social science disciplines to consider embeddedness as a conceptual framework that highlights the spatial and temporal nuances of how migrant-serving NGOs negotiate intersecting moral, legal, and political interests. We suggest that conceptualizing embeddedness as a spatio-temporal process nuances recent conversations regarding the ambiguous role of NGOs as either subordinated or subversive relative to migration management. Approaching (dis)embeddeding as a dynamic relational process, we argue, provides a framework for understanding how NGOs simultaneously align with and contest the interests of migration management amid shifting social, economic, and political conditions.

Molecular Mechanism of Tau Misfolding and Aggregation: Insights from Molecular Dynamics Simulation.

Tau dysfunction has a close association with many neurodegenerative diseases, which are collectively referred to as tauopathies. Neurofibrillary tangles (NFTs) formed by misfolding and aggregation of tau are the main pathological process of tauopathy. Therefore, uncovering the misfolding and aggregation mechanism of tau protein will help to reveal the pathogenic mechanism of tauopathies. Molecular dynamics (MD) simulation is well suited for studying the dynamic process of protein structure changes. It provides detailed information on protein structure changes over time at the atomic resolution. At the same time, MD simulation can also simulate various conditions conveniently. Based on these advantages, MD simulations are widely used to study conformational transition problems such as protein misfolding and aggregation. Here, we summarized the structural features of tau, the factors affecting its misfolding and aggregation, and the applications of MD simulations in the study of tau misfolding and aggregation.

M-mode ultrasound for assessment of the “tethered fat sign” in children: an easily performed way to certify a dynamic process as a still picture

M-mode ultrasound for assessment of the “tethered fat sign” in children: an easily performed way to certify a dynamic process as a still picture

Взаимосвязь окружной скорости и потерь энергии в проточной части центростремительной турбины с частичным облопачиванием рабочего колеса

Low-consumption turbomachines are devices that play an important role in the drive of various units in the field of shipbuilding, aircraft engineering and other branches of heavy engineering. They have some advantages over a high-average power turbine. The largest number of low-consumption turbomachines are made partial, i.e. with partial intake. The principle of a turbine with partial flapping of the impeller is considered as one of the types of partial turbomachines. The influence of the main velocity characteristic of the turbine stage on the loss of kinetic energy in the stage is investigated. The simulation of gas dynamic processes occurring in the turbine stage was carried out using the ANSYS Workbench software package. With the help of this complex, a three-dimensional geometric model of the turbine stage with varying degrees of impeller damping was created. By applying the finite element method, a computational grid, a computational model are generated, and boundary conditions of a numerical experiment are set. The result of the numerical experiment is graphs of the dependence of kinetic energy loss on the circumferential velocity (speed characteristics of the turbine stage). This dependence can be represented not only graphically, but also with the help of mathematical apparatus. An example of such an apparatus is the polynomial dependence. The considered mathematical design can be used in order to optimize mathematical models of gas flow in the flow part of a low-flow turbine. Cubic two-parameter polynomials of kinetic energy losses in the flow part of the nozzle and impeller are obtained, and an assessment of its applicability in the current mathematical model is given.

Tuning apicobasal polarity and junctional recycling in the hemogenic endothelium orchestrates the morphodynamic complexity of emerging pre-hematopoietic stem cells.

Hematopoietic stem cells emerge in the embryo from an aortic-derived tissue called the hemogenic endothelium (HE). The HE appears to give birth to cells of different nature and fate but the molecular principles underlying this complexity are largely unknown. Here we show, in the zebrafish embryo, that two cell types emerge from the aortic floor with radically different morphodynamics. With the support of live imaging, we bring evidence suggesting that the mechanics underlying the two emergence types rely, or not, on apicobasal polarity establishment. While the first type is characterized by reinforcement of apicobasal polarity and maintenance of the apical/luminal membrane until release, the second type emerges via a dynamic process reminiscent of trans-endothelial migration. Interfering with Runx1 function suggests that the balance between the two emergence types depends on tuning apicobasal polarity at the level of the HE. In support of this and unexpectedly, we show that Pard3ba - one of the four Pard3 proteins expressed in the zebrafish - is sensitive to interference with Runx1 activity, in aortic endothelial cells. This supports the idea of a signaling cross talk controlling cell polarity and its associated features, between aortic and hemogenic cells. In addition, using new transgenic fish lines that express Junctional Adhesion Molecules and functional interference, we bring evidence for the essential role of ArhGEF11/PDZ-RhoGEF in controlling the HE-endothelial cell dynamic interface, including cell-cell intercalation, which is ultimately required for emergence completion. Overall, we highlight critical cellular and dynamic events of the endothelial-to-hematopoietic transition that support emergence complexity, with a potential impact on cell fate.

In Situ Characterizations of the Dynamics of Cathode Electrolyte Interfaces at Different Current Densities.

LiNi0.8Mn0.1Co0.1O2 with high nickel content plays a critical role in enabling lithium metal batteries (LMBs) to achieve high specific energy density, making them a prominent choice for electric vehicles (EVs). However, ensuring the long-term cycling stability of the cathode electrolyte interfaces (CEIs), particularly at fast-charge conditions, remains an unsolved challenge. The decay mechanism associated with CEIs and electrolytes in LMB at high current densities is still not fully understood. To address this issue, in situ Fourier transform infrared (FTIR) is employed to observe the dynamic process of formation/disappearance/regeneration of CEIs during charge and discharge cycles. These dynamic processes further exacerbate the instability of CEIs as current density increases, leading to rupture and dissolution of CEIs and subsequent deterioration in battery performance because of continuous electrolyte reactions. Additionally, the dynamic changes occurring within individual components of CEIs at different cycling stages and various current densities are also discussed. The results demonstrate that excellent capacity retention at small current density is attributed to enrichment of inorganic compounds (Li2CO3, LiF, etc.) and rendering better stability and smaller expansion of CEIs. The key to achieving excellent electrochemical performance at high current densities lies on protecting CEIs, mainly inorganic components.

Predicting and probing the local temperature rise around plasmonic core-shell nanoparticles to study thermally activated processes.

Ultrafast spectroscopy can be used to study dynamic processes on femtosecond to nanosecond timescales, but is typically used for photoinduced processes. Several materials can induce ultrafast temperature rises upon absorption of femtosecond laser pulses, in principle allowing to study thermally activated processes, such as (catalytic) reactions, phase transitions, and conformational changes. Gold-silica core-shell nanoparticles are particularly interesting for this, as they can be used in a wide range of media and are chemically inert. Here we computationally model the temporal and spatial temperature profiles of gold nanoparticles with and without silica shell in liquid and gas media. Fast rises in temperature within tens of picoseconds are always observed. This is fast enough to study many of the aforementioned processes. We also validate our results experimentally using a poly(urethane-urea) exhibiting a temperature-dependent hydrogen bonding network, which shows local temperatures above 90 ◦C are reached on this timescale. Moreover, this experimentally shows the hydrogen bond breaking in such polymers occurs within tens of picoseconds.

The influence of dynamic pitching on the aerodynamic performance of large horizontal axis wind turbines

To delve into the aerodynamic changes of wind turbines during pitching, this study employs the user-defined function (UDF) and dynamic mesh technique. The dynamic aerodynamic performance of a 3.3 MW turbine blade during variable pitch is investigated via numerical simulation. The results show that the optimal pitch angle increases with increasing incoming wind speed. At the initial and final stages of pitch change, the wind turbine experiences the influence of impact loads, leading to minor fluctuations in torque and thrust coefficients. Within the dynamic pitch change process, the pitch angle notably affects the aerodynamic performance of airfoils at blade x/ c = 0~0.6 c cross sections. The primary stress area of the airfoil contracts, with the blade root experiencing comparatively less impact. In the constant-wind-speed pitching scenario, the low-speed region in the immediate wake of the wind turbine diminishes, resulting in a 10.7% enhancement in the average wind speed at 2.5D wake.

Equity split evolution in entrepreneurial teams: Assessing financial contributions and human capital

ABSTRACT Proper equity splits play a vital role in the success of entrepreneurial teams, yet the literature lacks a comprehensive understanding of their evolving nature. This study addresses this gap by analyzing the dynamic and evolutionary process of equity splits using longitudinal data. Through the development of a game-theory model incorporating human-capital signals, we illuminate the impact of these factors. Utilizing data from the Kauffman Firm Survey and employing fixed- and mixed-effects modeling, we uncover significant findings. Initially, financial contributions shape equity splits, but their influence diminishes as hidden human capital gains prominence. Education attainment and work experience have no direct effect, while prior entrepreneurial experience influences the initial year but not subsequent equity resplitting. Our research offers practical insights for making informed equity-split decisions in the early and later stages of ventures. Nonetheless, it’s important to note some limitations in our research stemming from the lack of information on individual entrepreneurs’ performance within entrepreneurial teams, which could enrich the measurement of hidden human capital.

Structural Insights of a cis-Epoxysuccinate Hydrolase Facilitate the Development of Robust Biocatalysts for the Production of l-(+)-Tartrate.

l-(+)-Tartaric acid plays important roles in various industries, including pharmaceuticals, foods, and chemicals. cis-Epoxysuccinate hydrolases (CESHs) are crucial for converting cis-epoxysuccinate to l-(+)-tartrate in the industrial production process. There is, however, a lack of detailed structural and mechanistic information on CESHs, limiting the discovery and engineering of these industrially relevant enzymes. In this study, we report the crystal structures of RoCESH and KoCESH-l-(+)-tartrate complex. These structures reveal the key amino acids of the active pocket and the catalytic triad residues and elucidate a dynamic catalytic process involving conformational changes of the active site. Leveraging the structural insights, we identified a robust BmCESH (550 ± 20 U·mg-1) with sustained catalytic activity even at a 3 M substrate concentration. After six batches of transformation, immobilized cells with overexpressed BmCESH maintained 69% of their initial activity, affording an overall productivity of 200 g/L/h. These results provide valuable insights into the development of high-efficiency CESHs and the optimization of biotransformation processes for industrial uses.

Inovasi Rekrutmen Aparatur Sipil Negara Menggunakan Sistem Computer Assisted Test (CAT)

CAT BKN is an innovation that contributes to the transformation of the ASN selection system in Indonesia. This innovation plays a very important role in preventing undesirable things, such as fraud in the CASN recruitment and selection process. Carrying out exams which usually use answer sheets and piles of question papers has become a selection system based on computer applications that is effective and efficient and reduces the opportunity for nepotism in recruitment. This article aims to look at the dynamics of the innovation process that occurred when CAT was formed as a method for CASN selection.

Duality between predictability and reconstructability in complex systems

Predicting the evolution of a large system of units using its structure of interaction is a fundamental problem in complex system theory. And so is the problem of reconstructing the structure of interaction from temporal observations. Here, we find an intricate relationship between predictability and reconstructability using an information-theoretical point of view. We use the mutual information between a random graph and a stochastic process evolving on this random graph to quantify their codependence. Then, we show how the uncertainty coefficients, which are intimately related to that mutual information, quantify our ability to reconstruct a graph from an observed time series, and our ability to predict the evolution of a process from the structure of its interactions. We provide analytical calculations of the uncertainty coefficients for many different systems, including continuous deterministic systems, and describe a numerical procedure when exact calculations are intractable. Interestingly, we find that predictability and reconstructability, even though closely connected by the mutual information, can behave differently, even in a dual manner. We prove how such duality universally emerges when changing the number of steps in the process. Finally, we provide evidence that predictability-reconstruction dualities may exist in dynamical processes on real networks close to criticality.

Terahertz spectroscopic study of the dehydration process and hydrogen bonding network of DL-glutamic acid and its monohydrate

The dehydration process involves the dissociation and reorganization of hydrogen bonds, and for the characterization of the dehydration process of amino acid-based hydrates, the analysis of their molecular vibrational modes and hydrogen bonds is still challenging nowadays. In this paper, the dynamic process of the dehydration of DL-glutamic acid monohydrate was monitored using terahertz spectroscopy. Quantitative simulations were performed on DL-glutamic acid and its monohydrate, with vibrational mode assignments and hydrogen bonding network analysis based on Density Functional Theory (DFT) for terahertz absorption peaks. The results show that the hydrogen bond stretching vibration is intermixed with atomic vibration. Specifically, the intermolecular hydrogen bond O4-H9···O2 of DL-glutamic acid exhibits a stronger vibration at 2.43 THz. Furthermore, the intramolecular hydrogen bond O5-H11···O4 in DL-glutamic acid monohydrate shows significant changes in bond length and bond angle at 1.85 THz. These findings validate the effectiveness of terahertz spectroscopy in monitoring the transformation process of the hydrate and the analysis of the hydrogen bond.

A taxonomy of didactic roles of dynamic visualization in animated mathematics videos

Abstract In recent years, a multitude of innovative educational videos focusing on mathematics and employing dynamic visualization techniques have been published on YouTube. From a sample of videos, we develop a taxonomy of didactical roles of dynamic visuals and supporting animation techniques. The taxonomy is constructed through an open coding approach, involving an iterative process of defining, analysing and refining the codes. Additionally, we conducted an interview with a video creator about the intended roles of dynamic visuals employed in his animations. The taxonomy encompasses the following categories of roles: connect objects, (co)vary objects, dynamic concept visualization, dynamic process visualization, symbol sense, connect to reality and generalization. These roles are implemented through animation techniques like moving and morphing. The nomenclature of these roles suggests their affiliation with various mathematics education research perspectives, including covariational thinking, concept–process duality, symbol sense and conversion between registers. The taxonomy serves as a foundational framework for further research into the learning outcome and effectiveness of dynamic visualization in educational mathematics videos.

Spatial distribution of crystalline silicates in protoplanetary disks: How to interpret mid-infrared observations

Context. Crystalline silicates are an important tracer of the evolution of dust, the main building block of planet formation. In an inner protoplanetary disk, amorphous silicates are annealed because of the high temperatures that prevail there. These crystalline silicates are radially and vertically distributed by a disk turbulence and/or radial transport. Mid-infrared spectrographs are sensitive to the presence and temperature of micron-sized silicates, and the dust temperature can be used to infer their spatial distribution. Aims. We aim to model the spatial distribution of crystalline silicate dust in protoplanetary disks taking into account thermal annealing of silicate dust and radial transport of dust in the midplane. Using the resulting spatial distribution of crystalline and amorphous silicates, we calculated mid-infrared spectra to study the effect on dust features and to compare these to observations. Methods. We modeled a Class II T-Tauri protoplanetary disk and defined the region where crystallization happens by thermal annealing process from the comparison between crystallization and residence timescales ($ cryst res $). Radial mixing and drift were also compared to find a vertically well mixed region ($ ver drift $). We used the DISKLAB code to model the radial transport in the midplane and obtained the spatial distribution of the crystalline silicates for different grain sizes. We used MCMax, a radiative transfer code, to model the mid-infrared spectrum. Results. In our modeled T-Tauri disk, different grain sizes get crystallized in different radial and vertical ranges within 0.2 au. Small dust gets vertically mixed up efficiently, so crystallized small dust in the disk surface is well mixed with the midplane. Inward of 0.075 au, all grains are fully crystalline irrespective of their size. We also find that the crystallized dust is distributed out to a few au by radial transport, smaller grains more so than larger ones. Our fiducial model shows different contributions of the inner and outer disks to the dust spectral features. The $10 forsterite feature has an $ 30 <!PCT!>$ contribution from the innermost disk (0.07-0.09 au) and $<1 <!PCT!>$ from the disk beyond 10 au while the $33 feature has an $ 10 <!PCT!>$ contribution from both innermost and outer disks. We also find that feature strengths change when varying the spatial distribution of crystalline dust. Our modeled spectra qualitatively agree with observations from the Spitzer Space Telescope, but the modeled 10 mu m feature is strongly dominated by crystalline dust, unlike observations. Models with reduced crystallinity and depletion of small crystalline dust within 0.2 au show a better match with observations. Conclusions. Mid-infrared observations of the disk surface represent the radial distribution of small dust grains in the midplane and provide us with abundances of crystalline and amorphous dust, size distribution, and chemical composition in the inner disk. The inner and outer disks contribute more to shorter and longer wavelength features, respectively. In addition to the crystallization and dynamical processes, amorphization, sublimation of silicates, and dust evolution have to be taken into account to match observations, especially at $ where the inner disk mostly contributes. This study could interpret spectra of protoplanetary disks taken with the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope.

Applying Blockchain, Causal Loop Diagrams, and the Analytical Hierarchy Process to Enhance Fifth-Generation Ceramic Antenna Manufacturing: A Technology–Organization–Environment Framework Approach

This study used a technology–organization–environment (TOE) framework as the primary analytical tool to explore the burgeoning capabilities of blockchain technology in the area of 5G ceramic antenna development. A causal loop diagram (CLD) analysis is used to further clarify the complex dynamics and feedback mechanisms, and the impact of blockchain on the design, production, and deployment phases of ceramic antennas, which play a pivotal role in the development of 5G communications, is studied. We found that blockchain’s unique features, including its immutable ledger and decentralized architecture, have the potential to significantly improve the transparency, security, and efficiency of the ceramic antenna manufacturing process. Technology (T), organization (O), and environment (E) were used as the top factors, and the subfactors of TOE were selected and analyzed using the Analytic Hierarchy Process (AHP) by CLD. The AHP analysis was used to evaluate the relative importance of various internal and external factors affecting the adoption of blockchain technology. The integration of the TOE framework with AHP and CLD provides a comprehensive analytical tool that enhances the understanding of the complex dynamics in the 5G ceramic antenna manufacturing process. This methodological approach not only clarifies the interactions between technological, organizational, and environmental factors but also facilitates strategic decision-making through a structured evaluation of these factors. The AHP analysis showed that technical factors are the most important in the TOE analysis of 5G ceramic antenna manufacturing, with a weight of 0.427, which indicates the important role of technical factors in the development of ceramic antenna production. In addition, environmental and organizational factors were given weights of 0.302 and 0.271, respectively, confirming the importance of technological innovation and internal process optimization. In the subfactor of Technology (T), ‘Blockchain Technology’ has the highest ranking among the subfactors, with a global weight value of 0.129, emphasizing the importance of blockchain technology. This study explored the technical and organizational complexities of introducing blockchain technology into the 5G ceramic antenna manufacturing industry and, through an in-depth investigation of the potential benefits of such integration, it aims to propose new approaches to improve quality control and manufacturing efficiency. The research findings aim to contribute to the sustainable growth of the telecommunications industry by providing strategic recommendations for the application of blockchain technology in the production of 5G ceramic antennas.

Editorial Conclusion for the Special Issue “New Theory and Applications of Nonlinear Analysis, Fractional Calculus and Optimization”

Nonlinear analysis has widespread and significant applications in many areas at the core of many branches of pure and applied mathematics and modern science, including nonlinear ordinary and partial differential equations, critical point theory, functional analysis, fixed point theory, nonlinear optimization, fractional calculus, variational analysis, convex analysis, dynamical system theory, mathematical economics, data mining, signal processing, control theory, and many more [...]

Exploring the inhibition effect of tri-sodium phosphate concentrations on corrosion in Mg-sn-ca-mn anode for magnesium batteries

ABSTRACT The corrosion of magnesium (Mg) alloy anodes poses a significant challenge in the development of magnesium-based batteries. In this study, the inhibition effect of different concentrations of TSP in sodium chloride (NaCl) solution on the corrosion behaviour of Mg alloy anodes in magnesium batteries was investigated. The immersion periods were varied to assess the long-term efficacy of TSP as a corrosion inhibitor. Tafel polarisation analysis revealed a shift in corrosion potential towards more noble values with increasing TSP concentration, indicating enhanced corrosion resistance. EIS measurements provided insights into the changes in charge transfer resistance and double-layer capacitance, corroborating the protective effect of TSP against corrosion. Furthermore, CV and LSV analyses elucidated the dynamic corrosion processes and confirmed the efficacy of TSP as a corrosion inhibitor. This study comprehensively investigates the inhibition mechanism of TSP on the corrosion behaviour of Mg alloy anodes in magnesium batteries.