Line Integrals Research Articles

Assessing organizational cohesion by the maximum caliber method

PurposeThe aim of this paper is to explore the conditions under which organizational networks achieve high levels of cohesion. It focuses on understanding the roles of interaction cycles, feedback loops and asymmetries in fostering cohesive networks. The study examines how the application of line integrals in closed paths can reveal insights into the cycles and feedback mechanisms influencing cohesion within these networks.Design/methodology/approachThis research uses the maximum caliber method to quantify organizational cohesion through the analysis of interactivity matrices. This approach integrates temporal dynamics and accounts for the complex interdependencies among actors within the network. The study is supported by a case study analysis, which demonstrates the practical application of these theoretical concepts in a real-world organizational context.FindingsThe application of the maximum caliber method offers a comprehensive understanding of organizational cohesion by effectively capturing the dynamic interactions within the network. The study reveals that cycles and feedback mechanisms within the network significantly affect cohesion, with interaction asymmetries playing a crucial role. The method also enables the identification of actors who contribute positively or negatively to cohesion, providing actionable insights for improving organizational performance.Originality/valueThis paper presents a novel methodological approach to analyzing organizational cohesion, enhancing both the theoretical and practical understanding of network dynamics. The findings provide valuable insights for organizational leaders and researchers, emphasizing the importance of managing interaction patterns to strengthen overall network cohesion and effectiveness. This approach offers a new perspective on measuring and influencing organizational cohesion, with significant implications for strategic management and organizational development.

A simulation platform for slender, semiflexible, and inextensible fibers with Brownian hydrodynamics and steric repulsion

The last few years have witnessed an explosion of new numerical methods for filament hydrodynamics. Aside from their ubiquity in biology, physics, and engineering, filaments present unique challenges from an applied-mathematical point of view. Their slenderness, inextensibility, semiflexibility, and meso-scale nature all require numerical methods that can handle multiple lengthscales in the presence of constraints. Accounting for Brownian motion while keeping the dynamics in detailed balance and on the constraint is difficult, as is including a background solvent, which couples the dynamics of multiple filaments together in a suspension. In this paper, we present a simulation platform for deterministic and Brownian inextensible filament dynamics, which includes nonlocal fluid dynamics and steric repulsion. For nonlocal hydrodynamics, we define the mobility on a single filament using line integrals of Rotne–Prager–Yamakawa regularized singularities and numerically preserve the symmetric positive definite property by using a thicker regularization width for the nonlocal integrals than for the self-term. For steric repulsion, we introduce a soft local repulsive potential defined as a double integral over two filaments, then present a scheme to identify and evaluate the nonzero components of the integrand. Using a temporal integrator developed in previous work, we demonstrate that Langevin dynamics sample from the equilibrium distribution of free filament shapes and that the modeling error in using the thicker regularization is small. We conclude with two examples, sedimenting filaments and cross-linked fiber networks, in which nonlocal hydrodynamics does and does not generate long-range flow fields, respectively. In the latter case, we show that the effect of hydrodynamics can be accounted for through steric repulsion.

Improving Fault Classification Accuracy Using Wavelet Transform and Random Forest with STATCOM Integration

INTRODUCTION: Fault detection in transmission lines is critical for keeping the grid stable and reliable. This research offers a new methodology, the Wavelet Transform-Enhanced Random Forest Fault Classification System with STATCOM Integration (WERFCS-SI), to solve the shortcomings of existing fault detection approaches. OBJECTIVES: The integration of STATCOM-compensated transmission lines improves fault detection capabilities. The Wavelet Transform finds faults by analysing approximation and detail coefficients, allowing for multiresolution analysis and exact fault localisation. METHODS: Feature selection approaches, such as information gain, are used to discover and keep relevant features, increasing classification accuracy. RESULTS: Due to its ability to process complex, high-dimensional data and identify minute feature connections, Random Forest (RF) is utilised for classification tasks. The proposed approach improves RF model performance while maintaining precision. CONCLUSION: The integrated technique simplifies fault categorisation, increasing accuracy and efficiency by detecting problems in the transmission line system.

Optimal weighting strategies for maximizing contrast-to-noise ratio in photon counting CT images.

Photon counting detectors (PCDs) with energy discrimination capabilities have the potential to generate grayscale CT images with improved contrast-to-noise ratio (CNR) through optimal weighting of their spectral measurements. This study evaluates the CNR performance of grayscale CT projections and images generated from spectral measurements of PCDs using three energy-weighting strategies: pre-log weighting, post-log weighting, and material decomposition (MD) weighting. This study provides the expressions of optimal weights and maximum achievable CNR of these energy-weighting strategies, which only require the knowledge of detected bin counts and do not require information of PCD energy responses or imaging techniques. We defined and solved a generalized eigenvalue problem to obtain the maximum achievable CNR in the projection domain for low-contrast tasks using three energy-weighting strategies: pre-log weighting (weighted sum of energy bin counts), post-log weighting (weighted sum of line integrals), and MD weighting (weighted sum of basis material thicknesses, which is equivalent to virtual monoenergetic images [VMIs]). These expressions only contain energy bin counts from PCD measurements. We used a realistic PCD energy response model to simulate the detected bin counts and conducted Monte Carlo simulations of different contrast tasks and phantoms to evaluate the projection- and image-domain CNR performance of these energy-weighting strategies. Additionally, the total counts method (a special case of pre-log weighting with unity weights) was included for comparison. We also conducted Gammex head and body phantom scans on an edge-on-irradiated silicon PCCT prototype to evaluate the image-domain CNR performance of these energy-weighting strategies. The results show that pre-log, post-log, and MD weighting strategies generate approximately equal projection-domain maximum achievable CNR, with a difference of less than 2%, and outperform the total counts method. These three energy-weighting strategies also generate approximately equal image-domain maximum CNR when the contrast task is located at the center of a homogeneous phantom. Pre-log weighting generates the highest image-domain CNR for an off-center contrast task location or inhomogeneous phantoms while also outperforming the total counts method. We derived the expression of projection-domain maximum achievable CNR using three energy-weighting strategies. Our results suggest that using pre-log weighting strategies enables fast grayscale CT image generation with high CNR from spectral PCD measurements for inhomogeneous phantoms and off-center region of interests (ROIs).

A composite microstrip line and leaky wave antenna structure with self-diplexing characteristic

A novel structure is proposed for the dual-band self-diplexing integration of microstrip line and leaky wave antenna (LWA). Through introducing a mode selective transmission line (MSTL) to the antenna, the autonomous transition between transmission modes at varying operating frequencies is thus achieved. At the high-frequency band, such proposed antenna in the quasi-TE10 mode, the periodic slots, and patches are used as LWA. Meanwhile, at the low-frequency band, the baseband signal with quasi-TEM mode can be transmitted effectively. These experimental results demonstrate that this design strategy benefits the realization of transmission with an insertion loss of less than 3 dB below 5.5 GHz. Furthermore, this antenna enables continuous beam scanning of −1 space harmonics from 10.5 to 15.5 GHz, with a beam direction sweeping from −75° to + 54°. This study innovatively employs MSTL structure to solve the problem of radio frequency (RF) and baseband links operating independently in traditional communication systems. It provides a promising solution for multi-functional integrated applications in future wireless communications.

Free energy formulae for confined nematic liquid crystals based on analogies with Kirchhoff–Routh theory in vortex dynamics

Active nematics are influenced by alignment angle singularities called topological defects. The localization of these defects is of major interest for biological applications. The total distortion of alignment angles due to defects is evaluated using Frank free energy, which is one of the criteria used to determine the location and stability of these defects. Previous work used the line integrals of a complex potential associated with the alignments for the energy calculation (Miyazako and Nara 2022 R. Soc. Open Sci . 9 , 211663 (doi: 10.1098/rsos.211663 )), which has a high computational cost. We propose analytical formulae for the free energy in the presence of multiple topological defects in confined geometries. The formulae derived here are an analogue of Kirchhoff–Routh functions in vortex dynamics. The proposed formulae are explicit with respect to the defect locations and conformal maps, which enable the explicit calculation of the energy extrema. The formulae are applied to calculate the locations of defects in so-called doublets and triplets by solving simple polynomial formulae. A stability analysis is also conducted to detect whether defect pairs with charges ± 1 / 2 are stable or unstable in triplet regions. Our numerical results are shown to match the experimental results (Ienaga et al. 2023 Soft Matter 19 , 5016–5028. (doi: 10.1039/d3sm00071k )).

Advancing Sustainable Higher Education: Embracing the Triple Bottom Line Integration in Uganda

The purpose of this conceptual paper was to revise Triple Bottom Line Theory of sustainable development as proposed by John Elkington, so as to propose ways of advancing sustainable higher education in Uganda. The major tenets of this theory are economic viability, environmental sustainability and social responsibility. Reduced fiscal spending by governments to higher education, the global calls for mitigation of climate change, youth unemployment and equity calls for higher education to be sustainable, including in Uganda. This paper concludes by proposing that sustainable higher education in Uganda is as a result of : Economic viability (job creation, skill development, research & innovation, community engagement, global education- partnerships with international institutions), environmental sustainability (integration of sustainability in curricula, use of experiential learning, collaboration with stakeholders, addressing resource limitations, empowerment and economic benefits) and social responsibility (community engagement, addressing local and global challenges, integrating social responsibility into missions, and merging social responsibility with internationalization efforts). The paper concludes by recommending empirical validation of the model, both in Uganda and outside Uganda

An advanced dual-layered framework for sustainable supply chain performance

Purpose This study aims to evaluate the sustainable supply chain performance indicators. At a macro level, the identification of the sustainable supply chain management (SSCM) performance indicators is done through exhaustive literature survey and interviews with experts. Furthermore, these indicators are evaluated through a hybrid approach, i.e. total weighted interpretive structural modelling (TWISM) followed by analytic hierarchical process (AHP). Design/methodology/approach Micro small and medium enterprises (MSMEs) in India are a major contributor to nation’s GDP. However, this sector struggles to comprehend benefits from implementation of SSCM due to a lack of appropriate performance evaluation metrics. The purpose of this paper is to contribute to the body of knowledge in SSCM by proposing and evaluating a set of SSCM performance indicators. Findings The paper highlights the SSCM performance indicators and concludes that business strategies, implementation planning and impact of stakeholders are the top SSCM performance indicators (SPIs). Therefore, the decision-makers must initially focus on strategic requirements which foster the implementation of SSCM, thereby ensuring profitability for all stakeholders. Research limitations/implications Although the proposed framework was validated through a case study on Indian automobile component manufacturing MSMEs, future research would explore the extension of the framework to other industries. Originality/value The originality of this study lies in the application of the novel TWISM-AHP tool. Furthermore, the SPIs identified in the study, consider the integration of the triple bottom line from the MSME perspective. The TWISM-AHP analysis will be beneficial for SC decision-makers to enhance the SSCM performance based on the identified indicators and their criticality.

Assembly Line Integration as a Lever for Efficiency and Space Utilization in Automotive Parts Production

Optimizing space in manufacturing is essential because space is both limited and expensive. Efficient use of space improves productivity, efficiency, and factory layout planning. The aim is to reduce the area used while increasing the value generated per unit of space, aligning with lean manufacturing principles that focus on value-adding activities and minimizing waste, including wasted space. In manufacturing, space optimization involves analyzing areas that add value, support operations, or cause waste. Key considerations include workspace design, safety clearances, and the overlap of functional areas, which can complicate space utilization. Effective floor space planning compares different layout options and measures space usage across categories to find the most efficient arrangement. Simple layout changes can greatly improve space efficiency by up to 80% without requiring large investments. This is crucial for boosting production efficiency and adapting to challenges, like those presented by the COVID-19 pandemic, which highlighted the need for flexible and efficient use of space to maintain safety and operations.

Business Management and Environmental, Social and Corporate Governance: The Tripod of Sustainability in Organizations

Objective: To analyze the applicability of the triple bottom line in organizations, aiming to integrate social, environmental and economic practices to promote sustainable development. Methodology: A quantitative exploratory approach was adopted to investigate managers’ perceptions about the integration of environmental, social and economic practices in organizations. Exploratory research was chosen to explore an emerging theme in the literature and business practice, identifying patterns and trends. A convenient sample of 92 managers was selected based on accessibility and relevance of experience, ensuring valuable insights. A structured questionnaire with closed questions and evaluation scales was used, developed based on a literature review and consultations with experts. Data analysis, carried out with descriptive statistics, such as means and percentages, highlighted patterns in managers’ perceptions about the implementation of the triple bottom line in companies. Results and discussions: The results reveal that there is a growing recognition of the importance of environmental practices, although they are not always absolutely prioritized. Internal resistance to change was identified as one of the main obstacles to implementing sustainable practices, along with challenges in measuring social and environmental impacts. On the other hand, the research highlighted opportunities such as strengthening corporate image, improving stakeholder relations and accessing new markets, suggesting that the effective integration of the triple bottom line is not only feasible, but crucial for long-term business success. Final considerations: The research demonstrated that the integration of the triple bottom line in organizations is not only feasible, but also fundamental to promoting sustainable development. Despite the growing recognition of the importance of environmental practices, internal resistance to change and difficulties in measuring social and environmental impacts represent significant challenges. However, the results also highlighted opportunities such as strengthening corporate image, improving stakeholder relations and accessing new markets. These findings underscore the need for business strategies that balance economic efficiency with social and environmental responsibility, aiming not only at profit, but also at long-term sustainability.

A novel family of Q1-finite volume element schemes on quadrilateral meshes

A novel family of isoparametric bilinear finite volume element schemes are constructed and analyzed to solve the anisotropic diffusion problems on general convex quadrilateral meshes. These new schemes are obtained by employing a special quadrature rule to approximate the line integrals in classical Q1-finite volume element method. The new quadrature rule is a linear combination of trapezoidal and midpoint rules, and the weights depend on a parameter ωK. The novelty of this work is that, for any fully anisotropic diffusion tensor, we provide some specific ωK to ensure the coercivity result of the proposed schemes on arbitrary parallelogram, quasi-parallelogram, trapezoidal and some general convex quadrilateral meshes. More interesting is that, the parameter ωK can only involves the anisotropic diffusion tensor and the geometry of quadrilateral cell. An optimal H1 error estimate is also proved on quasi-parallelogram meshes. Finally, the theoretical findings are validated by several numerical examples.

Improvement of 3D printing and subsequent microwave freeze-drying solidification accuracy of pineapple gel-based inks: Infill percentage control and internal models design

The purpose of this study was to improve the 3D printing accuracy of pineapple gel and its subsequent microwave freeze drying (MFD) solidification precision based on infill percentage control (30%, 50%, 70%, and 90%) and internal models design (Hilbert curve, honeycomb, and rectilinear). Through comparing the designed models with the physical dimensions of the printed and dehydrated products, the optimal regulation strategy was obtained. Results showed that the printing deviation of samples decreased initially and then increased with higher infill percentages, with the 70% infill percentage having the lowest deviation. Among all internal models, the rectilinear infill pattern showed the best printing accuracy. Porosity and the shape deformation rate of MFD solidification products initially decreased and then increased with higher infill percentages. The 70% infill percentage products had the lowest shape deformation rate. The honeycomb infill pattern performed best in reducing solidification sample shrinkage and deformation. Additionally, micro-CT scans revealed that the honeycomb infill pattern helped maintain the integrity of each layer's lines of MFD solidification products, closely matching the model's line distribution. In the 50% and 70% infill percentage, honeycomb and rectilinear samples exhibited better crispness. A 70% honeycomb infill pattern was recommended for optimal printing and post-solidification accuracy.

Printed polymer platform empowering machine-assisted chemical synthesis in stacked droplets

Efficiently exploring organic molecules through multi-step processes demands a transition from conventional laboratory synthesis to automated systems. Existing platforms for machine-assistant synthetic workflows compatible with multiple liquid-phases require substantial engineering investments for setup, thereby hindering quick customization and throughput increasement. Here we present a droplet-based chip that facilitates the self-organization of various liquid phases into stacked layers for conducting chemical transformations. The chip’s precision polymer printing capability, enabled by digital micromirror device (DMD)-maskless photolithography and dual post-chemical modifications, allows it to create customized, sub-10 µm featured patterns to confine diverse liquids, regardless of density, within each droplet. The robustness and open design of surface-templated liquid layers actualize machine-assistant droplet manipulation, synchronous reaction triggering, local oscillation, and real-time monitoring of individual layers into a reality. We propose that, with further integration of machine operation line and self-learning, this droplet-based platform holds the potential to become a valuable addition to the toolkit of chemistry process, operating autonomously and with high-throughput.

Protective effect of 5,4'-dihydroxy-6,8-dimethoxy7-O-rhamnosylflavone from Indigofera aspalathoides Vahl on lipopolysaccharide-induced intestinal injury in mice.

Intestinal inflammation is one of the main health challenges affecting the quality of life of millions of people worldwide. Accumulating evidence introduces several flavonoids with multifaceted therapeutic properties in inflammatory diseases including intestinal inflammation. Herein, we examined potential anti-inflammatory properties of 5,4'-dihydroxy-6,8-dimethoxy7-O-rhamnosylflavone (DDR) flavone derived from Indigofera aspalathoides Vahl (I. aspalathoides Vahl) on lipopolysaccharide (LPS)-induced intestinal inflammation and injury in mice. Oral DDR treatment decreased serum levels of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1β. It reduced oxidative stress through augmenting the activities of catalase (CAT) and superoxide dismutase (SOD) and reducing the level of malondialdehyde (MDA) in the duodenum and colon tissues. Moreover, DDR enhanced the activities of digestive enzymes including trypsin, pancreatic lipase, and amylase, and increased the production of short-chain fatty acids (SCFAs) by colon microbiota. Histopathological investigation of duodenum and colon revealed that DDR inhibited inflammatory infiltration and largely restored mucosal architecture and protected lining integrity. Importantly, DDR suppressed activation of nuclear factor-κB (NF-κB) signaling pathway through reduced expression of Toll-like receptor 4 (TLR4) and expression and phosphorylation of P65. The current study identified DDR as anti-inflammatory flavonoid capable of ameliorating LPS-induced intestinal inflammation through suppression of NF-κB signaling.

Robotical Automation in CNC Machine Tools: A Review

Abstract Robotics and automation have significantly transformed Computer Numerical Control (CNC) machining operations, enhancing productivity, precision, and efficiency. Robots are employed to load and unload raw materials, workpieces, and finished parts onto CNC machines. They can efficiently handle heavy and bulky components, reducing the demand of manual labour and minimizing the risk of injuries. Robots can also be used in CNC machine tools to perform tasks such as automatic tool changing system, part inspection, and workpiece positioning. Automation technologies, including in-line inspection systems and Non-Destructive Testing (NDT) methods, can be integrated into CNC machining cells to enhance accuracy and reduce scrap and rework in machining operations. These systems collect real-time data on process parameters and machine tool performance to predict maintenance, optimize machining parameters, and improve overall efficiency. In the current study, applications of robotics and automation in the modification of CNC machine tools are reviewed and discussed. Different applications of robotics and automation in CNC machine tools, such as automated material handling, automatic tool changing, robotic work cells, adaptive machining, machine tending, quality inspection, data monitoring and analysis, and production line integration, are discussed. Thus, by analysing recent achievements in published papers, new ideas and concepts of future research works are suggested. As a result, accuracy as well as productivity in the process of part production can be enhanced by applying robotics and automation in CNC machining operations.

Digital horizontal crosstalk compensation in 8K LCD displays for enhanced image quality

AbstractAs ultra‐high‐definition displays have gained popularity, mitigating the horizontal crosstalk effect in 8K LCD panels is crucial. High display resolution requires narrower signal line integration, intensifying the coupling effect. Traditional methods like Vcom feedback and increasing analog voltage drain‐drain (AVDD) load are slower and less accurate, leading to increased power consumption. In response, we propose an advanced digital signal compensation method. In this study, we developed a predictive model and investigated the intricate relationships among AVDD, Vcom, and storage capacity (Cst) ripples on horizontal crosstalk. Optimizing the ripple change (∆G) by varying the compensation coefficient (a) and decay ratio (τ) significantly reduces crosstalk effects. The digital compensation method allows rapid and precise compensation without delays, reducing horizontal crosstalk in 8K LCD panels from 4% to below 0.9%. This surpasses the requirement of minimizing crosstalk to less than 2%, substantially enhancing the image quality of high‐resolution displays.

Extraction of stress intensity factors of biharmonic equations with free boundary conditions on crack faces (III): SIF of a thin plate subjected to the bending moment

The plate bending problems in the Kirchhoff–Love model can be reduced to biharmonic equations. In the previous papers (Kim et al., 2020; Kim et al., 2022), we derived stress intensity factors (SIF) extraction formulas of a biharmonic equation Δ2u=f in a non-convex (cracked, L-shaped) domain with various boundary conditions such as clamped, simply connected, free, and mixed. In previous papers, we could not show a general SIF formula related to Poisson’s ratio ν contained in the free boundary condition. Moreover, the previous SIF extraction formula obtained for a given Poisson’s ratio requires cumbersome line integrals. In this paper, removing the line integrals in the extraction formulas, we show improved SIF extraction formulas applicable to biharmonic equations with free boundary conditions. Thus, the new, improved SIF extraction formulas for free boundary conditions become more straightforward and can be applied to plate bending problems.

Action of the Axial U(1) Non-Invertible Symmetry on the ’t Hooft Line Operator: A Lattice Gauge Theory Study

Abstract We study how the symmetry operator of the axial $U(1)$ non-invertible symmetry acts on the ’t Hooft line operator in the $U(1)$ gauge theory by employing the modified Villain-type lattice formulation. We model the axial anomaly by a compact scalar boson, the “QED axion”. For the gauge invariance, the simple ’t Hooft line operator, which is defined by a line integral of the dual $U(1)$ gauge potential, must be “dressed” by the scalar and $U(1)$ gauge fields. A careful consideration on the basis of the anomalous Ward–Takahashi identity containing the ’t Hooft operator with the dressing factor and a precise definition of the symmetry operator on the lattice shows that the symmetry operator leaves no effect when it sweeps out a ’t Hooft loop operator. This result appears inequivalent with the phenomenon concluded in the continuum theory. In an appendix, we demonstrate that the half-space gauging of the magnetic $\mathbb {Z}_N$ 1-form symmetry, when formulated in an appropriate lattice framework, leads to the same conclusion as above. A similar result is obtained for the axion string operator.

StraitFlux – precise computations of water strait fluxes on various modeling grids

Abstract. Oceanic transports shape the global climate, but the evaluation and validation of this key quantity based on reanalysis and model data are complicated by the distortion of the used curvilinear ocean model grids towards their displaced north poles. Combined with the large number of different grid types, this has made the exact calculation of oceanic transports a challenging and time-consuming task. Use of data interpolated to standard latitude/longitude grids is not an option, since transports computed from interpolated velocity fields are not mass-consistent. We present two methods for transport calculations on grids with variously shifted north poles, different orientations, and different Arakawa partitions. The first method calculates net transports through arbitrary sections using line integrals, while the second method generates cross sections of the vertical–horizontal planes of these sections using vector projection algorithms. Apart from the input data on the original model grids, the user only needs to specify the start and endpoints of the required section to get the net transports (for the first method) and their cross sections (for the second method). Integration of the cross sections along their depth and horizontal extent yields net transports in very good quantitative agreement with the line integration method. This allows us to calculate oceanic fluxes through almost arbitrary sections to compare them with observed oceanic volume and energy transports at available sections, such as the RAPID array or at Fram Strait and other Arctic gateways, or to compare them amongst reanalyses and to model integrations from the Coupled Model Intercomparison Projects (CMIPs). We implemented our methods in a Python package called StraitFlux. This paper represents its scientific documentation and demonstrates its application on outputs of multiple CMIP6 models and several ocean reanalyses. We also analyze the robustness and computational performance of the tools, as well as the uncertainties in the results. The package is available on GitHub and Zenodo and can be installed using pypi.

Blue GaN-based DFB laser diode with sub-MHz linewidth.

Distributed feedback laser diodes (DFBs) serve as simple, compact, narrow-band light sources supporting a wide range of photonic applications. Typical linewidths are on the order of sub-MHz for free-running III-V DFBs at infrared wavelengths, but linewidths of short-wavelength GaN-based DFBs are considerably worse or unreported. Here, we present a free-running InGaN DFB operating at 443 nm with an intrinsic linewidth of 685 kHz at a continuous wave output power of 40 mW. This performance is achieved using a first-order embedded hydrogen silsesquioxane (HSQ) surface grating. The frequency noise is measured using a cross-correlated self-heterodyne frequency discriminator, and two estimations of integrated linewidth are evaluated using 1/π integration and β-separation line integration methods.