Longer Distances Research Articles

Life cycle costing analysis of a retrofitted hydrogen-powered locomotive: Canadian context

The transportation sector must adopt cleaner alternatives to meet global emission reduction goals and attain net-zero emissions by 2050. Hydrogen stands out as a promising solution for decarbonizing the railway sector. This study conducts an economic assessment of hydrogen locomotives, considering their entire life cycle. Life cycle costs are analyzed across various travel scenarios and life stages. For shorter distances, the operational phase and capital costs of retrofitting components contribute 64% and 21% to the total life cycle costs, respectively. In contrast, longer distances are dominated by the operational phase, representing nearly 90% of the total costs. Clean hydrogen must reduce costs to compete with diesel locomotives, as only non-sustainable hydrogen currently matches diesel operational expenses. Anticipated advancements in hydrogen technology are expected to make clean hydrogen more accessible, leading to a significant reduction in the life cycle costs of hydrogen locomotives.

The Single Nucleotide Variant rs17602729 (C34T) of the <i>AMPD1</i> Gene is Associated with Athletic Qualification and Competitive Distance in Caucasian Cyclical Sports Athletes

All physiological processes necessary for high athletic performance, including energy production in skeletal muscles and the peculiarities of metabolic processes (phosphogenic pathway, glycolytic, aerobic) are genetically determined. The enzyme Adenosine Monophosphate Deaminase is an important regulator of skeletal muscle energy metabolism during exercise. The identification of genetic biomarkers that determine the effectiveness of ATP resynthesis is one of the priorities of sports genetics. (1) Background: To study the associations of SNV rs17602729 (C34T) allelic variants and genotypes of the AMPD1 gene with qualification and competitive distance in Caucasian athletes of the Southern Urals. (2) Methods: 173 people of European origin who lived in the Southern Urals region took part in the study. The first group included 123 cyclical sports athletes (speed skating, running disciplines in track-and-field): SD (short distances) subgroup ‒ 40 sprinters (mean - 22.1 ± 2.4 y.o.); MD (middle distances) subgroup ‒ 38 athletes (mean - 20.1 ± 2.5 y.o.); subgroup LD (long distances) – 45 stayer athletes (mean - 22.6 ± 2.7 y.o.). The control group consisted of 50 healthy non–athletes (mean ‒ 21.4 ± 2.7 y.o.). We used the Step One Real-Time PCR System (Applied Biosystems, USA) device for real-time polymerase chain reaction. (4) Conclusions: the common allele with rs17602729 of the AMPD1 gene can be considered as a biomarker associated with short and medium competitive distances. It can help in the selection of elite athletes who require effective performance of anaerobic sports loads. The variable T allele is an unfavorable biomarker (negative predictor) for achieving the status of Honored Master of Sports and Sport Master of International Class in athletics and speed skating, regardless of the competitive distance.

Laguerre-Gaussian laser filamentation for the control of electric discharges in air.

We study the use of Laguerre-Gaussian (LG) femtosecond laser filament with multi GW peak power to guide electric sparks in the atmosphere. We demonstrate that an LG beam with a vortex phase or with 6 azimuthal phase steps generates a filamentation regime, where a longer and more uniform energy deposition is produced compared to a normal beam with a flat phase. Such filaments can guide electric discharges over much longer distances. This technique could significantly extend the guiding range of laser filaments for lightning control and other long-range atmospheric experiments involving filamentation.

Max-convolution processes with random shape indicator kernels

In this paper, we introduce a new class of models for spatial data obtained from max-convolution processes based on indicator kernels with random shape. We show that these models have appealing dependence properties including tail dependence at short distances and independence at long distances. We further consider max-convolutions between such processes and processes with tail independence, in order to separately control the bulk and tail dependence behaviors, and to increase flexibility of the model at longer distances, in particular, to capture intermediate tail dependence. We show how parameters can be estimated using a weighted pairwise likelihood approach, and we conduct an extensive simulation study to show that the proposed inference approach is feasible in relatively high dimensions and it yields accurate parameter estimates in most cases. We apply the proposed methodology to analyze daily temperature maxima measured at 100 monitoring stations in the state of Oklahoma, US. Our results indicate that our proposed model provides a good fit to the data, and that it captures both the bulk and the tail dependence structures accurately.

2024: anticipating record-breaking performances in front crawl swimming through mathematical analysis.

Introduction: This study presented a novel approach to predict future front crawl swimming world records (WRs) by employing a methodology that integrated performance data from both running and front crawl swimming. Methods: By extracting the top one running and swimming performances from 1995 to 2023 and applying a model that correlates physiological characteristics such as maximum aerobic power, anaerobic capacity, the decrement in maximum power with prolonged effort, and performance speed and duration, it was possible to project the potential record-breaking performances in 2024 across various swimming distances for both male and female athletes. Furthermore, this approach was expected to be less susceptible to the influence of the full-body swimsuit era, which may have disrupted the typical trajectory of swimming performance progression. Results: The average relative error between the top one and estimated speeds in front crawl swimming (50-1,500m, from 1995 to 2023, and for male and female) was 0.56% ± 0.17%. For male, WR in longer distances have been predicted with new WR in the 400 and 800m. A more ambitious prediction was noted among female, with twice as many WR as among male illustrated by new WR in the 50, 200, 400 and 800m. Discussion: This study illustrated that the utilization of a prediction model based on physiological parameters yielded plausible time estimates. Additionally, the research accentuated the ongoing trajectory of surpassing existing WR into 2024, illustrating the competitive zeal fueled by an emerging framework of exceptional swimmers.

Outcomes and risk factors of transported patients with extracorporeal membrane oxygenation: An ECMO center experience

BackgroundExtracorporeal membrane oxygenation (ECMO) has been proven to be a support method and technology for patients with cardiopulmonary failure. However, the transport of patients under ECMO support is challenging given the high-risk technical maneuvers and patient-care concerns involved. Herein, we examined the safety of ECMO during the transport of critically ill patients and its impact on mortality rates, to provide more secure and effective transport strategies in clinical practice. MethodTo assess the safety of ECMO patient transport, this study conducted a retrospective analysis on critically ill adults who required ECMO support and transport at the intensive care unit (ICU) center between 2017 and 2023. The study utilized standard ECMO transport protocols and conducted a comprehensive statistical analysis of the collected clinical data and transport processes. The 28-day survival rate for ECMO patients was determined using Kaplan–Meier analysis, while logistic regression identified prognostic factors. ResultOut of 303 patients supported with ECMO, 111 (36.6%) were transported. 69.4% of the transport group were male, mean age was (42.0±17.0) years, mean body mass index was (24.4±4.6) kg/m2, and veno-arterial-ECMO accounted for 52.5%. The median transportation distance was 190 (interquartile range [IQR]: 70–260) km, and the longest distance was 8100 km. The median transit time was 180 (IQR: 100–260) min, and the maximum duration was 1720 min. No severe adverse events including death or mechanical failure occurred during transportation. The 28-day survival was 64.7% (n=196) and ICU survival was 56.1% (n=170) for the entire cohort; whereas, the 28-day survival was 72.1% (n=80) and ICU survival was 66.7% (n=74) in the transport group. A non-significant difference in survival (P=0.56) was observed between the two groups after propensity score matching. Additionally, we found that acute physiology and chronic health evaluation II score (odds ratio [OR]=1.06, P <0.01), lactate levels (>5 mmol/L, OR=2.80, P=0.01), and renal replacement therapy initiation (OR=3.03, P <0.01) were associated with increased mortality risk. ConclusionTransporting patients on ECMO between medical facilities is a safe procedure that does not increase patient mortality rates, provided it is orchestrated and executed by proficient transport teams. The prognostic outcome for these patients is predominantly influenced by their pre-existing medical conditions or by complications that may develop during the course of ECMO therapy. These results form the basis for the creation of specialized ECMO network hubs within healthcare regions.

Pathological evaluation of tumor immune microenvironment before first-line anti-PD1 plus anti-angiogenic therapy in patients with unresectable hepatocellular carcinoma (HCC): Towards a prediction for treatment efficacy.

e14662 Background: Immune checkpoint inhibitor (ICI) combined with anti-angiogenic therapy is the standard first-line treatment for unresectable HCC patients. However, most patients do not derive durable benefit and will progress faster. Simultaneously, sufficient clinically validated biomarkers to stratify patients are lacking in HCC. Recent studies have shed a light on the strong connection between immunotherapy efficacy and tumor immune microenvironment (TIME) in HCC. Thus, this study aims to investigate TIME features before treatment to develop a potential way for survival prediction which may optimize risk stratification. Methods: A total of 84 unresectable HCC patients who received first-line ICI plus anti-angiogenic therapy at Nanjing Drum Tower Hospital were included. 4 multiplex immunohistochemistry (mIHC) panels containing 18 biomarkers were developed to thoroughly evaluate immune cells in TIME before therapy, such as cytotoxic T cells, tissue-resident memory T cells, macrophages and neutrophils. TIME features were then extracted from raw image by digital pathology, including cell subpopulation abundance and spatial profiling. We identified a list of TIME features associated with objective response rate (ORR), progression free survival (PFS) and overall survival (OS), and developed a TIME-based risk score (TIS) in our cohort using machine-learning. Results: After data cleaning, a total of 78 patients with complete clinical information and TIME features were included and split into training and validation sets. A higher positive rate of CD103+ cells and CD8+ cells were observed in responder, while patients with higher CD66b+ positive rate showed shorter PFS and OS. In terms of spatial profiling, tumor cells accompanied with more CD8+ cells were associated with longer PFS and OS, while longer distance from CD14+ cells and CD66b+ cells to tumor cells favored longer PFS and OS. Regarding PFS prediction, our machine-learning model TIS included both immune cell abundance and spatial features. Stratifying patients in the low- and high-risk groups using TIS revealed prolonged PFS (p&lt;0.0001, HR: 0.24, 95%CI [0.13-0.45]) and OS (p = 0.00057, HR: 0.27, 95%CI [0.12-0.60]) in TIS low-risk group. Moreover, ORR in TIS low-risk group was 52.9% (17/34) and 15.9% (7/44) in TIS high-risk group. Univariable and multivariable analysis demonstrated that TIS was an independent predictor for ORR (p = 0.0017), PFS (p = 0.00065) and OS (p = 0.00042). Independent validation is still awaited. Conclusions: This study demonstrates that our machine-learning based risk score can improve treatment response and survival prediction using TIME features, which provides the potential to optimize risk stratification before first-line treatment for unresectable HCC patients.

Integration of GNSS, Total Station, and Grid Controls: An Analysis of Combined Effect of Elevation of Topography and Map Projection Distortion to Solve the Distance Discrepancy

Heterogeneous measurements from various surveying methods need to be integrated to accomplish any survey project. The use of Global Navigation Satellite System (GNSS) and Total Station (TS) to establish a control framework along with utilizing existing national grid controls, for any survey project has been the standard practice. However, the successful integration of GNSS, TS, and existing grid controls could be challenging at times. Both survey professionals, and surveying stakeholders would benefit from the successful augmentation of heterogeneous measurements from GNSS, TS, and existing grid controls in order to provide a control framework for their survey project. In the past, the distance discrepancy/mismatch of GNSS-derived distance which is obtained from indirect measurements from GNSS survey and TS distance which is ground-based direct measurements, has created confusion. Herein, we have analyzed in detail, the combined effect of elevation of topography and map projection's distortion on the distance; demonstrate the magnitude of combined effect by numerical examples; tested this formulation with real-world GNSS and TS measurements. This way we proposed a solution to solve distance discrepancy/mismatch between various survey methods. The magnitude of the combined effect would be substantial with higher elevations and longer distances and could cross the threshold of specified/required accuracy. The effect would be more pronounced in mountainous regions suggesting combined effect should be properly taken into account. Taking combined effect into consideration brings the compatibility and comparability of GNSS, TS, and existing grid controls together. Thus, allowing both survey professionals and surveying stakeholders to utilize the mix of GNSS, TS, and existing grid controls to achieve required precision and accuracy in an economical, timely, and easy manner.

Grounded Ambitions: A Lean Approach for Assessing Beachability in Concept Design

Littoral operations have become an increasing interest for defense stakeholders over the last several decades. Many navies currently operate ship-to-shore assets that are designed to travel shorter distances exclusively in the littorals between a ship and the beach. New concepts are being designed to transit much longer distances from shore-to-shore in both blue water and littoral regions. This Concept of Employment (CONEMP) drives these ships to displacements that are orders of magnitude larger. Compared to smaller vessels where seakeeping and maneuverability performance in the surf-zone are a significant area of interest, larger vessels have a comparatively greater risk with respect to the ability of the ship to get far enough up a beach to safely deliver assets and then get off the beach. This research presents the foundation for a new simulation tool to analyze how far up the beach a ship will be able to get given loading condition, initial speed, beach condition, and hull shape. The focus of this research is to provide a low computational-cost method for analyzing the beachability of a ship that still considers the dominating physical phenomena of grounding at early stages of design. The tool will need much faster turnaround times than high-fidelity Reynolds-Averaged Navier-Stokes (RANS) or Finite Element Analysis (FEA) simulations to support the rapid and evolving environment of concept design timelines.

Just How River‐Like Are Atmospheric Rivers?

AbstractAtmospheric Rivers (ARs) are synoptic‐scale conduits for poleward transport of heat and water, often associated with extreme rainfall. Using NASA surface heat flux observations and climate model simulations, we assess whether ARs are “rivers”, transporting heat and moisture over longer distances, or mostly local convergence. The observations indicate that ARs reduce extratropical surface energy fluxes, even during early development. This damping of surface fluxes during ARs is also simulated in the Goddard Institute for Space Studies ModelE, 2.1 (GISS‐E2.1) nudged to (MERRA2) reanalysis winds. Furthermore, water provenance tracers in GISS‐E2.1 identify the moisture source for ∼7,500 ARs globally during 2018–2022 as farther upstream and equatorward compared to climatology. These results quantitatively show that ARs source relatively less moisture from the surface beneath them and more from a greater distance than during non‐AR times.

Indoor AR Navigation Framework Based on Geofencing and Image-Tracking with Accumulated Error Correction

This study presents a novel framework for improving indoor augmented reality (AR) navigation with modern smartphone technology, which is achieved by addressing two major challenges: managing large absolute coordinate spaces and reducing error accumulation in camera-based spatial tracking. Our contribution is significant in two ways. First, we integrate geofencing with indoor navigation by considering spatial tracking errors, timing for audio guidance, and dynamic 3D arrow visualization for effective local-to-global spatial coordinate transformation. This method achieves precise local positioning and seamlessly integrates with larger spatial contexts, overcoming the limitations of current AR systems. Second, we introduce a periodic image-based calibration approach to minimize the inherent error accumulation in camera-based tracking, enhancing accuracy over longer distances. Unlike prior studies focusing on individual technologies, our work explores the software architecture of indoor AR navigation by providing a comprehensive framework for its design and practical use. The practicality of our approach is validated through the implementation of a smartphone application at the Mineral Industry Museum of Akita University, highlighting the limitations of component technologies and demonstrating our framework’s effectiveness.

Effects of Seed Size and Frequency on Seed Dispersal and Predation by Small Mammals.

Frequency-dependent predation is common in predator-prey interactions. Size is an important characteristic of seeds and is crucial in the regeneration stage of plant seeds. However, the frequency dependence of animal predation on seed size has not been reported. In this study, we conducted a field experiment and used different sizes of Liaodong oak (Quercus wutaishanica) seeds to test the frequency dependence of intraspecific seed size selection in rodents. We used the number ratio of large to small seeds as the frequency. The results show that the rate of small seeds being eaten in situ was significantly higher than that of large seeds (p < 0.05). The rates of different-sized seeds being eaten after removal decreased with increasing frequencies, and there was no significant difference between frequencies except for 1:9 and 9:1. The rates of large seeds being scatter-hoarded were significantly higher than those of small seeds at different frequencies (p < 0.05). The eating distances after removal of large seeds were significantly longer than those of small seeds at the same frequencies (p < 0.05). Furthermore, the scatter-hoarding distances of large seeds were significantly longer than those of small seeds at three frequencies (1:9, 3:7, and 9:1) (p < 0.05). That is, rodents consumed more small seeds in situ, dispersed and scatter-hoarded more large seeds, and dispersed large seeds over longer distances. Rodents exhibited a negative frequency dependence for small seeds and a positive frequency dependence for large seeds on being eaten in situ. Moreover, rodents exhibited a negative frequency dependence for large seeds and a positive frequency dependence for small seeds on being eaten after removal and scatter-hoarding. These results reveal the frequency dependence of rodent selection on seed size and provide new insights into animal-mediated seed dispersal and the regeneration of plant populations.

Determining Desired Speeds from Vehicle Trajectory Data

Desired speed or free speed distributions are important input parameters for microscopic traffic flow simulations. Whereas driven speeds can be measured, desired speeds are not detectable for all vehicles because of vehicles constraining each other. An established approach to estimating desired speed distributions is the modified Kaplan–Meier approach, which estimates desired speed distributions based on single vehicle data from stationary detectors. We propose a novel approach to determine desired speeds based on vehicle trajectory data. The proposed approach, as well as the modified Kaplan–Meier approach, is applied to a trajectory dataset recorded on a German freeway. With the modified Kaplan–Meier approach, we observed that the resulting desired speed distributions vary by approximately 5 km/h depending on the position of the stationary detectors. The desired speed distributions obtained from the trajectory-based approach are approximately 5 to 10 km/h higher than those estimated by the modified Kaplan–Meier approach. This difference in results is probably because the trajectory-based approach observes each vehicle over a longer distance rather than just at stationary points. Nevertheless, it can be concluded that the estimation of desired speed distributions is subject to a certain degree of inaccuracy. The analysis of the vehicle trajectory data revealed a notable intra-vehicle instability in desired speeds, with a difference of 5 to 7 km/h observed for 40% of the vehicles between different periods of free driving. These findings should be considered in the context of calibrating microscopic traffic flow simulations.

Performance pathways in elite middle- and long-distance track and field athletes: The influence of a successful youth

ObjectivesThere is limited information on the performance progression of athletics endurance athletes from junior-to-senior status and the determinants of success in adulthood. This study aimed to quantify the youth-to-senior transition rate, the likelihood of success and the relationship between youth and senior performance amongst world-class athletes competing in middle- and long-distance disciplines. DesignRetrospective design examining public data between 2000 and 2019. MethodsThe performances of 4678 international athletes (45.3 % female) were analysed. World's all-time top 50 athletes were identified for U18 and Senior categories (age ≥ 20 years). Youth-to-senior transition rate and transition probabilities were calculated. Correlations between best U18 and Senior performances were determined to assess the stability of the performance. ResultsThe youth-to-senior transition rate for top U18 athletes was low for males and females (~19 % and 21 %). Nevertheless, the probability of transition to a top senior was ~7 times higher for top U18 athletes than for non-top U18 athletes. The correlations between youth and senior best performances were low-to-high. ConclusionsFew top U18 athletes maintained top world ranking status during their senior careers. Still, they are more likely to become top senior athletes than those who did not perform at the top level in U18. The association between youth and senior performance is stronger when comparing the same discipline or when athletes competed over longer distances in their senior compared to U18 career. Being a successful youth athlete may represent a small advantage for future success, however, it does not guarantee advancement to the senior top level.

Measurement of mandibular incisive canal diameter using cone beam computed tomography

Cone beam computed tomography was used for measuring the diameter of a Mandibular incisive canal. The dental practice can now visualize small bone structures with low dose and high spatial resolution due to the introduction of CBCT (Cone Beam Computed Tomography). Therefore, it is of interest to measure the diameter of the MIC (Mandibular Incisive Canal) using the CBCT. Fifty CBCT scans obtained for implant placement preoperative planning were included in the study material. Observers carefully examined the CBCT data to determine the MIC’s presence &amp; position. The inner diameter of the MIC was measured by taking the longest distance between the inner cortical borders of the canal which was further analyzed using software CS3D software. The collected data were further subjected to statistical analysis. The average mean of the population was 1.7130±.5178. The average diameter of MIC in males was 1.735±.5406 and in females was 1.6800±.4934. Complications from implant surgery in the anterior mandible may be prevented by utilizing CBCT scans to analyze the smallest diameter of the MIC.

Magnetic field impact on ferronanofluid laminar flow

A comprehensive understanding of the magnetic field interaction with the flow of ferronanofluids is essential to determine the heat transfer effect and the potential for use in industrial applications. The purpose of this work is to determine the effects of magnetic field orientation and intensity, as well as inertia forces, on heat transfer in the laminar flow of a ferronanofluid. The experiment involved the use of five permanent magnets positioned both below and above the flowing magnetite-based ferronanofluid. The analysis of the effect on heat transfer is carried out using the similarity numbers, Reynolds number (ratio of inertia and viscous forces), magnetic number (ratio of magnetic and inertia forces) and product of the two (ratio of magnetic and viscous forces).The findings indicate that the orientation of the magnetic field relative to temperature gradient-induced secondary motions plays a crucial role in either enhancing or inhibiting heat transfer. The magnet positioned below the flow leads to improved heat transfer, while placement above hinders it. To determine the magnetic field effect on heat transfer, the ratio of magnetic to viscous force introduced as MnRe is used. Taking the 5 % Nusselt number change as the threshold, the critical value for the orientation of magnet above the tube is MnRe = 24,000, while for the configuration with the magnet below, MnRe = 32,000 for Re = 109 and MnRe = 88,000 for Re = 150 and 163. The magnetic field effect is local and diminishes as the fluid flows, ultimately causing the heat transfer parameters to revert to their reference state. However, an increase in the ratio of inertia and viscosity forces enables the magnetic field interaction effect to propagate over a longer distance.

The Effect of Technological Progress on Yarder Productivity: An Example from the Bulgarian Mountains

In recent years, a significant import of modern tower yarders has been registered in Bulgaria, where official productivity standards are routinely used for operational planning and control. Given the higher potential of the newer yarder models, the Bulgarian forestry sector has started a review of the older productivity standards dating back to the 1970s. This new endeavor has offered an ideal opportunity for gauging the effect of technological progress in yarder technology. Therefore, the authors have used the very first results achieved during the development of the new standards for conducting a preliminary quantitative comparison between older and newer yarder types. Modern yarders (e.g., Konrad Mounty 4000) are much faster than the older ones (e.g., Koller K300), and their time consumption per cubic meter is half as large, especially on longer distances. At short distances, however, their performance evens out. Regardless of the distance, the installation time of the Konrad Mounty 4000 is twice as short. As they are largely automated, the new machines can be manned by smaller crews (e.g., two workers instead of three) and are easier and safer to operate. Finally, the new machines are equipped with built-in loaders and processors, which allows them to integrate delimbing, crosscutting and stacking within the same work cycle. With older models, a separate team must be deployed for those tasks.

Perfect vortex beams with periodic coherence properties

Partially coherent perfect vortex beams with periodic coherence properties, namely, optical coherence perfect vortex lattices (OCPVLs), are proposed in this letter. Rhombus-, spiral-, and circle-shaped OCPVLs were investigated in detail both theoretically and experimentally through the manipulation of the coherent structures. Manipulating the coherence width yielded unique advantages, such as maintaining uniformity over a longer distance, more efficient optical trapping, and high-capacity free-space optical communications. OCPVLs with such advantages hold outstanding potential for applications in multi-particle trapping and manipulation.

Dynamic Node Selection Approach for 6G Heterogeneous Cellular Networks (HCN) to Enhance QoS and Low Latency

A wireless multi-hop network is a group of nodes that can interact directly with one another or across longer distances by using other nodes as relay points and routers. 6G heterogeneous cellular network support several transmission modalities, such as single hop, multi-hop transmission and device-to-any device transmission. These transmission services can greatly increase 6G cellular network capacity, spectral efficiency, power efficiency, Quality of Service (QoS) and Ultra Reliable Low Latency Communication (URLLC). According to current research, Heterogeneous Cellular Networks (HCN) can benefit even more from the integration of demand-driven opportunistic networking into HCN. Devices can search look for the connections between nodes that are most efficient. in Proactive HCN connections by taking advantage of the URLLC acceptability of many mobile data services. Multiple Transmission modes necessitate node selection schemes that can determine the best node for each transmission. Previous proposals for node selection schemes have taken into account the introduction of D2X and HCN. Proactive HCN connections, however, cannot be incorporated into the selection process by current node selection schemes. By implementing outward the first node selection scheme that can incorporate Proactive HCN sharing information within 6G and beyond networks, this research work enhances the existing work. The analysis that was carried out shows the potential for Proactive HCN communications as well as the ability of the suggested node selection scheme to choose the best communication node to enhance QoS and Low Latency.

Influence of Stitch Angle on the Flexural Response of Composite Structures

Utilizing lightweight composites in aerospace vehicles plays a pivotal role in sustainability by improving fuel efficiency and mitigating emissions. However, due to their low interlaminar strength, delaminations and microcracking degrade their strength and stiffness properties. Through-thickness stitching improves the interlaminar strength, thus increasing the delamination tolerance of composite structures. Therefore, in this study, the influence of repeated periodic stitching patterns, stitched at three different angles (0, 45, and 90°) w.r.t. the transverse direction, on the flexural properties of stitched composites is investigated. The strain distributions of these specimens were obtained using a single continuous optical fiber bonded to the tensile surface of the specimens. The results show that stitching at a 45° angle produced lower strains and higher flexural strength and bending modulus when compared to the stitched and unstitched laminates. An increase of 32.3 and 47.4% in the flexural strength and bending modulus were obtained, respectively, with reference to the unstitched laminates. The failure morphology of specimens was also analyzed using optical microscopy and revealed that the stitch seams arrested delaminations. However, due to the 45° angle, the damage progressed along a longer distance, thus resulting in an increased ultimate failure load.