Non-overlapping Configuration Research Articles

Microstructure generation of long fiber reinforced hybrid composites using the fused sequential addition and migration method

We present a fused sequential addition and migration (fSAM) algorithm to generate synthetic microstructures for long fiber reinforced hybrid composites. To incorporate the bending of long fibers, we model the fibers as polygonal chains and use an optimization framework to search for a non-overlapping fiber configuration with the desired properties. As microstructures of hybrid composites consist of materials with varying characteristics, e.g., different fiber orientation distributions or fiber volume fractions, the unit cell needs to be divided in subcells. Then, the objective function is required to account for the characteristics of the subcells individually. To ensure that the location of a fiber is restricted to its respective subcell, we apply box constraints during the optimization procedure. Depending on the materials and the manufacturing processes, the interfaces within hybrid composites show either strict separation or interlocking of the different materials. Hence, we enable selecting the box-constraint type to model the interface according to the desired composite. We provide a detailed discussion of the extensions of the original fSAM algorithm to generate hybrid composites, considering two alternative procedures to handle the box constraints during the optimization procedure. As the selection of the box-constraint type influences the synthetic microstructures, we investigate the shape of the interfacial areas and the computed effective stiffnesses. Last but not least, to validate the capability of the fSAM algorithm to generate representative microstructures, we compare the resulting mechanical behavior with experimental data.

Robust Human Activity Recognition for Intelligent Transportation Systems Using Smartphone Sensors: A Position-Independent Approach

This study explores Human Activity Recognition (HAR) using smartphone sensors to address the challenges posed by position-dependent datasets. We propose a position-independent system that leverages data from accelerometers, gyroscopes, linear accelerometers, and gravity sensors collected from smartphones placed either on the chest or in the left/right leg pocket. The performance of traditional machine learning algorithms (Decision Trees (DT), K-Nearest Neighbors (KNN), Random Forest (RF), Support Vector Classifier (SVC), and XGBoost) is compared against deep learning models (Gated Recurrent Unit (GRU), Long Short-Term Memory (LSTM), Temporal Convolutional Networks (TCN), and Transformer models) under two sensor configurations. Our findings highlight that the Temporal Convolutional Network (TCN) model consistently outperforms other models, particularly in the four-sensor non-overlapping configuration, achieving the highest accuracy of 97.70%. Deep learning models such as LSTM, GRU, and Transformer also demonstrate strong performance, showcasing their effectiveness in capturing temporal dependencies in HAR tasks. Traditional machine learning models, including RF and XGBoost, provide reasonable performance but do not match the accuracy of deep learning models. Additionally, incorporating data from linear accelerometers and gravity sensors led to slight improvements over using accelerometer and gyroscope data alone. This research enhances the recognition of passenger behaviors for intelligent transportation systems, contributing to more efficient congestion management and emergency response strategies.

Optimizing Wireless Network based on Building Design in Telkom University

Computer network designed according to its functions and building design which must be analyzed to consider usage intensity and maintenance. This paper’s study case is in one of the buildings in University at Bandung which uses fiber optic and wireless network for both 2,4GHz and 5GHz frequencies. Existing conditions were tested in site surveys which are high frequency interference of wireless signals, misconfigured channel bands caused frequent disconnections close to two different access points, and there are blank spots causing user’s devices cannot properly connect to network. Wireless network optimization needs to be done to solve its problems. Method used is the Network Development Life Cycle (NDLC) which consists of Analysis, Design, and Simulation Prototyping phases, and performance measurements using Quality of Service (QoS) parameters. Site survey results showed many high interference areas caused by channel misconfiguration in each access point that the same channel can be used for adjacent access points, misplacing wall-mounted access points on ceiling which can interfering both upper floor and lower floor networks. QoS performance measurements to match TIPHON Standardization for throughput is higher than 1kbps, packet loss lower than 3%, and delay lower than 150ms. Recommendation for optimizing network is properly configuring channel band using non-overlapping channel configuration (1-6-11) for all adjacent access points, and there is simulation for replacing wall-mounted access points that placed on the ceiling to a ceiling-mounted type access point. It showed a decreasing interference in the entire network, whether its on the same floor or between upper and lower floor.

Performance Improvement for double-stator permanent magnet synchronous machine using analytical subdomain model

An analytical subdomain model is employed in this paper for predicting the magnetic field distributions in a three-phase double-stator permanent magnet synchronous machine (DS-PMSM) during open-circuit and onload conditions. Due to the stator cores are located in the outer and inner parts of the motor, the DS-PMSM construction is quite complex. The rotor magnets are positioned between these two stators. The stator inner radius, stator outer radius, slot opening, magnet arc, magnet thickness, inner and outer air-gap thickness and number of windings turns will directly influence the motor performance in DS-PMSM. The analytical subdomain model employed in this paper has a significant advantage as a rapid design tool since it is capable of precisely predicting the performance of DS-PMSM while requiring less computational effort. The analytical model was initially created using the separation of variables technique in four subdomains based on the Poisson’s and Laplace’s equations: inner air-gap, inner magnet, outer magnet and outer air-gap. Applying the appropriate boundary and interface conditions yields the field solutions in each subdomain. Besides, the fractional DS-PMSM with different number of slots between outer and inner stators to rotor poles can result in low cogging torque and non-overlapping winding configuration. The analytical results are validated by Finite Element Analysis (FEA). The slotted air-gap flux density, back-emf, and output torque have all been evaluated as electromagnetic performances. The results demonstrate that the suggested analytical model is capable of accurately predicting the DS-PMSM performance.

Positions and covering: A two-stage methodology to obtain optimal solutions for the 2d-bin packing problem.

We present a two-stage methodology called Positions and Covering (P&C) to solve the two-dimensional bin packing problem (2D-BPP). The objective of this classical combinatorial NP-hard problem is to pack a set of items (small rectangles) in the minimum number of bins (larger rectangles). The first stage is the key-point of the Positions and Covering, where for each item, it is generated in a pseudo-polynomial way a set of valid positions that indicate the possible ways of packing the item into the bin. In the second stage, a new set-covering formulation, strengthen with three sets of valid inequalities, is used to select the optimal non-overlapping configuration of items for each bin. Experimental results for the P&C method are presented and compared with some of the best algorithms in the literature for small and medium size instances. Furthermore, we are considering both cases of the 2D-BPP, with and without rotations of the items by 90°. To the best of our knowledge, this is one of the first exact approaches to obtain optimal solutions for the rotation case.

A Comparative Study of Coreless-Type PM Linear Synchronous Machines With Non-Overlapping Windings

This paper presents the comparative study of coreless-type permanent magnet linear synchronous machines with non-overlapping windings. An analytical expression that can be applied to any combinations of pole and coil numbers is developed for evaluating the electromagnetic performances. Subsequently, a simple factor called thrust factor is introduced to find the best ${\boldsymbol{C}_{\boldsymbol{pp}}}$ family depending on the variation of coil width ratio. From the comparative study, a significant result is reported that ${\boldsymbol{C}_{\boldsymbol{pp}}} = 1/4$ , i.e., multiple 4-pole/3-coil, is the best non-overlapping winding configuration of coreless-type permanent magnet machines owing to the highest value of thrust factor. Finally, the validity of the key analyses is confirmed by optimal results, finite element results, and experimental results from prototype machines.

Comprehensive Study of Partially Shaded PV Modules With Overlapping Diodes

Bypass diodes are usually connected in PV modules to reduce the impact of partial shading. There are two configurations of the bypass diodes used in commercially available PV modules: non-overlapping bypass diodes, in which each diode is separately connected to a unique group of series PV cells, and overlapping bypass diodes, in which the diodes are connected to mutual PV cells. Because almost all PV studies are based on non-overlapping configuration, the effects of the diodes are well understood. On the other hand, a complete analysis for the effects of the overlapped bypass diodes on the performance of the PV module has not been yet systematically disclosed. Moreover, there is still no available mathematical formulation to model such PV modules without the use of circuit simulations. This paper first derives a mathematical modeling approach to simulate overlapped PV modules and then provides a comprehensive study and analysis for the effect of overlapped bypass diodes on the electrical response of PV module under a wide variety of possible shading levels to fully understand their effects and impact. Moreover, it reveals their effects on partial shading power losses, and on the hot spot formation, which both have not yet been investigated in the literature of overlapped PV modules. Their possible negative effects on the efficiency of micro inverters are also illustrated. The results are validated both using Matlab Simulink and experimentally.

Dendritic Self-Avoidance and Morphological Development of Cerebellar Purkinje Cells.

Cerebellar Purkinje cells arborize unique dendrites that exhibit a planar, fan shape. The dendritic branches fill the space of their receptive field with little overlap. This dendritic arrangement is well-suited to form numerous synapses with the afferent parallel fibers of the cerebellar granule cells in a non-redundant manner. Purkinje cell dendritic arbor morphology is achieved by a combination of dynamic local branch growth behaviors, including elongation, branching, and retraction. Impacting these behaviors, the self-avoidance of each branch terminal is essential to form the non-overlapping dendritic configuration. This review outlines recent advances in our understanding of the cellular and molecular mechanisms of dendrite formation during cerebellar Purkinje cell development.

Meta-heuristic Algorithms for Nesting Problem of Rectangular Pieces

Nesting problems consist of placing multiple items onto larger shapes finding a good arrangement. The goal of the nesting process is to minimize the waste of material. It is common to assume, as in the present work, that the stock sheet has fixed width and infinite height, since in the real world a company may have to cut pieces from a roll of material.The complexity of such problems is often faced with a two-stage approach, so-called “hybrid algorithm”, combining a placement routine and a meta-heuristic algorithm. Starting from a given positioning sequence, the placement routine generates a non-overlapping configuration. The encoded solution is manipulated and modified by the meta-heuristic algorithm to generate a new sequence that brings to a better value of the objective function (in this case the height of the strip).The proposed method consists in placing the rectangles inside a strip and in combining the meta-heuristic algorithms with the No Fit Polygon algorithm. The software has been developed in Python language using proper libraries to solve the meta-heuristic techniques (Inspyred) and the geometric problems (Polygon).The results show the effectiveness of the proposed method; moreover, with regard to problems reported in literature employed as benchmark of the nesting algorithms, the degree of occupation values (Efficiency Ratio, ER) are shown to be higher than 90%.

Simulating the Crack Propagation Mechanism of Pre-Cracked Concrete Specimens Under Shear Loading Conditions

The mechanism of crack propagation in concrete specimens containing cracks under shear loading conditions is studied. The shear box test of pre-cracked (double edge cracks) concrete specimens is carried out under laboratory conditions. The higher order displacement discontinuity formulation and the special crack tip elements for the treatment of crack ends is used to numerically simulate the crack propagation mechanism of brittle solids under direct shear loading. A special modeling technique is also proposed to take into account the effect of crack overlapping on the fracturing process of the bridge area in between the two parallel cracks. In this study, the wing cracks are produced at the first stage of loading and continued their propagation paths toward the shear loading direction. The crack propagation path of the double edge cracked specimens in the bridge area is mostly affected by ligament angles and crack length whereas the shear strength is closely related to the failure pattern. The coalescence mechanism of cracks indicated that the pre-cracked concrete failure occurs in mixed mode in case of non-overlapping cracks configuration and in tensile mode for the overlapping cracks. Finally, comparing the numerical and experimental results validated the crack propagation modeling and verified the accuracy and efficiency of the proposed numerical method.

“Positive” and “negative” edge dislocations simultaneously interacting with Σ11 GB during nanoindentation

Quasicontinuum simulations of “positive” and “negative” dislocations simultaneously interacting with Σ11 symmetrical tilt grain boundary (GB) during nanoindentation reveal two distinctive dislocation/GB interactions depending on the indenter size h and demarcated by a potential independent critical indenter size h¯cr. When h is less than h¯cr, lattice dislocations are eliminated by a reflected dislocation from dislocation-GB interaction. Meanwhile, less grain boundary dislocations (GBDs) are emitted. However, when h is greater than h¯cr, the “positive” and “negative” dislocations nucleate separately and interact with GB dependently due to one interaction site absorbing GBDs nucleated from another interaction site. The resulted GB configuration shows a regularly-stepped shape. Studies of a free-standing dissociated dislocation dipole (DP) shows that, hcr, depending on potentials, is a critical distance between two extended dislocations of a DP, at which the DP transforms configuration between stacking fault overlapping and non-overlapping configuration. The full edge DP model based on continuum theory, which does not take the strong interactions between partial dislocations into account, fails to predict hcr.

Cyclic pursuit in a multi-agent robotic system with double-integrator dynamics under linear interactions

SUMMARYWe investigate the controlled realization of a stable circular pursuit model in a multi-agent robotic system described by double-integrator dynamics with homogeneous controller gains. The dynamic convergence of the system starting from a randomly chosen, non-overlapping initial configuration to a sustained, stable pursuit configuration satisfying velocity matching and uniform inter-agent separation is demonstrated using the proposed control framework. The cyclic pursuit configuration emerges from local, linear, inter-agent interactions and is shown to be robust under stochastic perturbations of small and moderate intensities. The stability criterion discussed in this work is independent of the number of agents, permitting dynamic addition/deletion of agents without affecting overall system stability. Experimental results that validate the key theoretical results are also presented. Potential applications of the results obtained include cooperative perimeter tracking and resource distribution applications such as border patrol and wildfire monitoring.

Development of physical and numerical techniques of Alanine/EPR dosimetry in radiotherapy

In this work, a set of 50 alanine dosimeters has been used in a radiotherapy context, simulating a two-dimensional treatment in a non-overlapping dosimeter configuration. The dose is reconstructed from physical and numerical simulation of the electron paramagnetic resonance signal, calculating the spin density. Thus, it can be used to better adjust the error in the calibration curve to give a final accuracy of <0.03 Gy. A complete set of experimental test parameters have been used with a standard dosimeter in order to obtain the best analysis configuration. These results indicate that for a conventional treatment of some hundreds of mGy, this method can be useful with a correct signal validation. A numerical test and fitting software has been developed. The general use of alanine/electron paramagnetic resonance dosimetry in radiotherapy context is discussed.

The Synaptic Mechanism of Direction Selectivity in Distal Processes of Starburst Amacrine Cells

Patch-clamp recordings revealed that distal processes of starburst amacrine cells (SACs) received largely excitatory synaptic input from the receptive field center and nearly purely inhibitory inputs from the surround during both stationary and moving light stimulations. The direct surround inhibition was mediated mainly by reciprocal GABA(A) synapses between opposing SACs, which provided leading and prolonged inhibition during centripetal stimulus motion. Simultaneous Ca(2+) imaging and current-clamp recording during apparent-motion stimulation further demonstrated the contributions of both centrifugal excitation and GABA(A/C)-receptor-mediated centripetal inhibition to the direction-selective Ca(2+) responses in SAC distal processes. Thus, by placing GABA release sites in electrotonically semi-isolated distal processes and endowing these sites with reciprocal GABA(A) synapses, SACs use a radial-symmetric center-surround receptive field structure to build a polar-asymmetric circuitry. This circuitry may integrate at least three levels of interactions--center excitation, surround inhibition, and reciprocal inhibitions that amplify the center--surround antagonism-to generate robust direction selectivity in the distal processes.

Packing Boxes with Bricks

Brick-packing problems In a packing problem we must arrange a given collection of geometric objects in a nonoverlapping configuration to fill some larger object com pletely. Packing problems can be challenging even when only a few simple shapes are involved. For example, several innocuous-looking, but fiendish 3-dimensional packing problems were devised by J. H. Con way [23]. Tiling problems (2-dimensional packing problems) studied in the ancient world include tangrams in China and a conundrum of Archimedes, whose resolution merited a front page article in the New York Times in 2003 [25]. Jigsaw puzzles are familiar instances of more recent tiling problems. The packing problems most studied by mathematicians concern polyominoes?finite sets of rookwise-connected unit cells in an infinite chessboard?and their generalizations to higher dimensions. In this article, we examine packings of rectangular boxes with rectangular bricks. Even in this basic case the problems that arise are interesting and difficult. We treat ?/-dimensional bricks and boxes, including those whose edge lengths are not integers, and answer the following questions as we introduce our packing theorems and con structions.

Cloning of the maize rough dwarf virus genome: Molecular confirmation of the plant-reovirus classification scheme and identification of two large nonoverlapping coding domains within a single genomic segment

The segmented double-stranded RNA genome of maize rough dwarf virus, a plant-infecting reovirus of the genus Fijivirus, was cloned and partially characterized. Nucleotide sequence analysis of full-length cDNA clones corresponding to genomic segments S6, S7, and S8 revealed each segment to contain the conserved terminal oligonucleotide sequences (+) 5′ AAGUUUUUU------UGUC 3′ and adjacent, segment-specific, regions of inverted complementarity (inverted repeats), a structural motif previously reported for members of the genus Phytoreovirus. Genomic segment S6 was completely sequenced and found to consist of 2193 base pairs. Computer analysis indicated that the coding strand contained two large nonoverlapping open reading frames consisting of 363 and 310 codons and located in the 5′- and 3′-terminal domains, respectively. This was confirmed by cell-free translation studies with synthetic transcripts and denatured genomic RNA. However, only the product of the 5′-proximal open reading frame, a 40-kDa polypeptide, was efficiently expressed in vitro from the full-length S6 coding strand. This represents the first case in which a reovirus genomic segment was found to contain two large open reading frames in a nonoverlapping configuration, suggesting possible alternative strategies for regulation of gene expression by members of this genus. The combined results provide a molecular confirmation of the current classification scheme for plant-infecting reoviruses. Furthermore, the fact that the same terminal structural motif is conserved across genera provides additional evidence that these elements serve an important functional role during genome transcription or replication.

Coulomb interaction energy including overlap effects for the ground states of LiNa and Na 2

A recently proposed method to calculate first-order electrostatic as well as second-order induction and dispersion energies including charge-overlap effects for the interaction between two atoms each with one active electron is applied to the systems Li(2s) + Na(3s) and Na(3s) + Na(3s), giving the induction energy for both systems. The variation with R of the relative contribution of the overlapping and non-overlapping configuration space regions is discussed for the largest dispersion and induction terms.