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Herein, a novel combination with a focused morphology is designed after synthesizing CrVO4 (CV) nanoparticles and poly‐pyrrole nanotubes (PNT or P) to prepare the interlocks of the composites of PNT and CrVO4 as 1PCV1, 1PCV2, 2PCV1, and 2PCV2 to study the supercapacitor application. Structural and spectral characterizations are perpetuated to confirm the synthesis of the samples. Results furnishing best energy storage are obtained for the intercalated composite 2PCV1 examined for three‐probe and two‐probe set‐up. The excel values for specific capacitance (Cs) for 2PCV1 concerning the Cyclic voltammetry (CV) cycle and Galvanostatic Charge Discharge (GCD) curve are 1745.60 F g−1 at 10 mV s−1 rate and 1545.62 F g−1 at 0.625 A g−1 current density studied along with interface controlled and transport‐controlled Cs with a contribution of 55.13% interface part and 44.87% transport part at 5 mV s−1 scan rate. Electrochemical Impedance Spectroscopy (EIS) study has provided 0.86 n‐factor with solution resistance Rs of 1.48 Ω, and a charge transfer resistance of 0.166 Ω. The respective specific power and specific energy values obtained through the two‐probe set‐up are also interestingly high 416.68 W kg−1 and 45.14 Wh kg−1 at 0.83 A g−1 current density. Also, the retention % in Cs values is studied by running 5000 continuous voltammetric cycles with 96.23% retention in supercapacitor device. [ABSTRACT FROM AUTHOR]

Large-scale triaxial tests are popular for evaluating the mechanical properties of railroad ballast. The literature shows that different compaction methods have been used to prepare the samples. This research investigates the potential variation caused by different compaction methods, even when the samples are compacted to the same density. A series of triaxial tests are conducted, and the results confirm that the way in which ballast is compacted significantly affects its stiffness, but not its peak strength, as long as the density is consistent. Discrete-element method simulations are performed to explore this phenomenon and discover that stiffness variations are caused by different ways in which particles interlock and arrange themselves during compaction. Based on the findings from this study, it is recommended to consider the influence of compaction methods when conducting large-scale triaxial testing on railroad ballast or when evaluating the test results. [ABSTRACT FROM AUTHOR]

Copyright of Urban Mass Transit is the property of Urban Mass Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective In the multi-level road network, junction stations of lines with different signal systems face quite a number of challenges. In order to meet the new demands of multi-network interoperation, it is necessary to conduct in-depth research and propose interlocking functions and interface configuration solutions for junction stations. Method By comparing the differences between interlocking systems under CBTC and CTCS-2 signal systems, signal control function, construction and operation demands are analyzed in detail, and functional requirements of the junction station interlocking system are clarified. On this basis, the interface objects and interface contents of the interlocking system are further analyzed. Finally, a configuration scheme for the interlocking interface of the junction station is constructed. Result & Conclusion The junction station interlocking system not only needs to complete the basic route safety protection function, but is also able to adapt to the requirements of various signal systems for basic information provision, capable of mobile blocking adaptability, as well as comprehensive functions such as section block combination, platform door control, over lap section protection, automatic return route processing, flexible operation adjustment and adaptation. At the same time, the junction station interlocking system should support multi-channel interfaces such as signal safety data network, wired ring network, wireless network, relay, etc. to ensure the compatibility and reliability of the system.

Nature offers a valuable source of inspiration when designing optimized structures. For instance, when two or more shells are joined during growth processes, Nature prefers to exploit interlocking paradigms to enhance the strength of the bond—cranial sutures are one example. Mimicking this distinctive characteristic when welding thin metallic elements may offer some structural benefits. The present study theoretically investigates the possibility of mitigating the detrimental tensile residual stress that always originated by welding processes, by exploiting Computational Welding Mechanics. Specifically, two plates joined by laser welding following sinusoidal paths (i.e., wave‐like), alongside a linear one, will be studied and compared. Thanks to the distinctive temporal and spatial heat distributions of sinusoidal welding, both welding stress and strain develop in dissimilar ways compared with linear path welding—this is reflected to the resulting weldment distortion too. The results show that geometrically optimized sinusoidal welding can effectively reduce residual stress magnitudes compared with the linear configuration counterpart. The implications of these findings are of particular interest when dealing with the structural performance of welded structures, especially in fatigue contexts. Highlights: The effect of sinusoidal path welding on residual stress is investigated.The welding path significantly modifies the thermal history of the weld bead.Sinusoidal path welding offers an effective capability of tuning residual stresses. [ABSTRACT FROM AUTHOR]

Weight reduction strategies are essential for the transportation sector to reduce greenhouse gas emissions or extend the range of electric vehicles. In the field of lightweight assembly strategies, multi-material design offers great potential. Joining materials typically used in the automotive sector, such as aluminum and steel, brings challenges as conventional processes such as fusion welding are unsuitable. Therefore, new technologies can extend the design options. In previous studies, a mechanical interlocking between cold-rolled surface structures with undercuts on a steel sheet and die-cast aluminum was presented. This method has now been extended to double-sided structures for more complex applications with a joint on both sheet surfaces. Numerical simulations and validation experiments were performed to investigate the manufacturing of the double-sided structures. Furthermore, the influence of the alignment of the upper and lower structures in relation to each other on the resulting structural geometry and the rolling forces were analyzed. More advantageous geometric parameters, e.g., 24% larger undercuts, and approx. 24.1% lower forming forces at 20% height reduction were observed for a shifted alignment. However, significantly higher wear of the structured rollers occurred in the corresponding experiments. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AbstractFine-grained soils containing diatom microfossils exhibit unique geotechnical behavior due to their biological origins, but their strength properties controlled jointly by diatom content (DC) and stress history remain to be revealed. In this study, reconstituted diatomaceous soil was prepared by mixing pure diatom and kaolin powders in different proportions. These mixtures were subjected to undrained consolidated triaxial shear tests performed using the Stress History and Normalized Soil Engineering Properties (SHANSEP) procedures, revealing how the DC and stress history affect the soil strength. Adding diatoms improved the mixture strength, and a critical DC of approximately 20% was determined, beyond which the normalized undrained strength of the soil was considerably higher than that of common clay without diatoms. Also, a DC higher than 20% associates with the dilatancy of the studied soil with high OCR. Improving the strength of diatomaceous soil by adding diatoms differs essentially from the case of common clay because the plasticity index of the former remains almost unchanged. New formulas incorporating DC and OCR are proposed for predicting the strength of diatomaceous soil, and data for several well-studied soils confirm their validity. This study improves the understanding of fine-grained soils with biological origins and provides important data regarding the mechanical behavior of diatomaceous soil. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the interlayer bonding characteristics between double-layered asphalt systems. Three typical asphalt structures were chosen for evaluation. In each case, the bottom layer comprised of a dense graded asphalt concrete (AC-20) while three different asphalt mixtures were applied in surface layer: a dense graded mixture (AC-13), stone mastic asphalt (SMA-13), and open-graded friction course (OGFC-13). The effects of interface morphology, loading, and temperature conditions on interlayer bonding properties were considered. The interlayer shear and tensile strengths of the asphalt systems were tested using 'shear-compression' and 'shear-tensile' loading mode set ups, and the relationship between interface morphology and interlayer bond strength was quantitatively analyzed using 3D laser scanning. In addition, statistical analysis was performed to determine the significance level of each factor, followed by developing and validating prediction models for interlayer bond strength using multivariate nonlinear regression. The results showed that all factors had a significant effect on interlayer bonding performance, with temperature being the most prominent contributing factor. Increasing normal pressure had a positive effect on preventing the attenuation of interlayer shear strength, while an increase in shear stress was found to intensify the degradation of interlayer tensile strength. Moreover, interlocking and ensuring sufficient contact at the layer interface were demonstrated to enhance the interlayer friction effect positively. However, high normal stress could potentially lead to damage at the interface. Finally, the developed prediction models exhibited a high level of accuracy in estimating interlayer bond strengths and were able to explain over 97% and 98% of measured interlayer shear and tensile strengths, respectively. Employing a properly graded surface layer can improve the frictional and contact effects at the layer interface, thereby enhancing the overall interlayer bonding performance. [ABSTRACT FROM AUTHOR]

Digital design techniques and fabrication technologies have become essential in architectural design, influencing the design process significantly. The pursuit of form in both digital and physical environments is a priority in architectural education, promoting the development of students' multidimensional thinking skills. This article discusses a graduate course that aims to introduce digital design concepts and their integration with the fabrication techniques. The course focuses on students' interaction with digital tools during the design and fabrication stages, particularly emphasizing the design of interlocking modular structures. Through experiential engagement with design and fabrication tools, students enhance their problem-solving skills and gain new knowledge. The course concludes with testing the digital and physical production stages, demonstrating the positive impact of digital design techniques on students' learning and creative abilities. [ABSTRACT FROM AUTHOR]

This study focuses on PET waste reduction worldwide by looking at the application of these polymeric materials in the construction and building industries. An effective application of PET wastes will reduce PET pollution, especially in water bodies. Due to its rising cost, it can partially replace the conventional binder used (cement).Bricks were made in the conventional cement-sand and PET-sand, and a total of 72 cubes were produced for different mix ratios of 1:1, 1.5:1, and 2:1. Their properties like particle size analysis, water absorption, slump testing, and compressive strength were investigated and compared.The particle size analysis showed that the sand was well-graded with a Cu of 3.41 and a Cc of 1.07. The results of the water absorption test showed that, in both series and different mix ratios, the PET-sand interlocking blocks had a lower sorptivity (percentages of 2.02, 2.72, and 4.20) than the cement-sand interlocking blocks (percentages of 0.91, 2.40, and 3.31). The mixtures produced a 70 mm, 50 mm, and 80 mm slump for 1:1, 1.5:1, and 2:1, respectively.The maximum compressive strengths in cement-sand interlocking blocks were 13.89 N/mm2, 17.34 N/mm2, and 21.06 N/mm2 in the 1:1, 1.5:1, and 2:1 respectively. Although the results showed that the compressive strength of PET-sand interlocking bricks was lower than that of cement-sand interlocking bricks, it can be useful in a low-density carriage road.

Abstract Suckermouth armoured catfish (Loricariidae) are a highly speciose and diverse freshwater fish family, which bear upper and lower lips forming an oral disc. Its hierarchical organisation allows the attachment to various natural surfaces. The discs can possess papillae of different shapes, which are supplemented, in many taxa, by small horny projections, i.e. unculi. Although these attachment structures and their working mechanisms, which include adhesion and interlocking, are rather well investigated in some selected species, the loricariid oral disc is unfortunately understudied in the majority of species, especially with regard to comparative aspects of the diverse oral structures and their relationship to the ecology of different species. In the present paper, we investigated the papilla and unculi morphologies in 67 loricariid species, which inhabit different currents and substrates. We determined four papilla types and eight unculi types differing by forms and sizes. Ancestral state reconstructions strongly suggest convergent evolution of traits. There is no obvious correlation between habitat shifts and the evolution of specific character states. From handling the structures and from drying artefacts we could infer some information about their material properties. This, together with their shape, enabled us to carefully propose hypotheses about mechanisms of interactions of oral disc structures with natural substrates typical for respective fish species.

This study investigates blast dynamics of prestressed segmented columns assembled of osteomorphic interlocking elastic blocks without any binding materials or mechanical connectors. The unique ability of the interlocking structures to absorb and dissipate energy through the independent movement of their segments is analyzed using the nonlinear finite element method. The effects of the number of blocks, the axial prestress, the friction, and the level of interlocking between the contact surfaces on the flexural response and energy absorption capability of the segmented column are investigated parametrically. It is demonstrated that the detachments between blocks control the energy absorption capability of these structures. Therefore, the number of blocks, the axial prestress, and the level of interlocking (i.e., the parameters influencing the available detachment between blocks) define the response of this column to blast loads. Columns segmented into a greater number of blocks with lower prestress levels exhibit a higher damping capability but reduced column stiffness, which is usually undesirable in structural applications. A higher level of interlocking between the contact surfaces of blocks increases the damping capacity of the column without reducing its stiffness. The effect of friction is found to be insignificant for all cases considered. The effect of interlocking is small relative to the effects of prestress and the number of blocks. However, it provides an independent design parameter for the passive mitigation of blast loads. [ABSTRACT FROM AUTHOR]

This article suggests a new waveguide design that utilizes a "walled" architecture. Instead of relying on conventional gap waveguide structures to create electronic bandgaps and prevent field leakage, the proposed design introduces a "walled" guiding mechanism. This technique preserves transmission while maintaining the multilayer approach and eliminates the need for nails or chemical bonds to attach the layers. Simulations were carried out in the W-band (75–110 GHz) and D-band (110–170 GHz) using several metals, and measurements were performed in the W-band using aluminum. The simulation results show that the reflection coefficient was less than −40 dB over the entire D-band. At the same time, the average insertion loss was around 0.0054 dB/mm and around 0.0065 dB/mm for silver and gold, respectively. Similarly, the reflection coefficient was less than −45 dB over the 75–110 GHz range, with an average insertion loss of 0.0018 dB/mm for silver and 0.003 dB/mm for gold, respectively. The aluminum model's reflection coefficient was less than −35 dB, and the average insertion loss was 0.0035 dB/mm. The experimental results achieved a reflection coefficient of less than –30 dB and the average transmission coefficient was −0.2 dB, with an insertion loss of 0.002 dB/mm. The simple stacking ability of the weightless walled metal plates and easy fabrication makes the proposed transmission line a promising technology in mmWave and Terahertz applications. [ABSTRACT FROM AUTHOR]

In the geotechnical area, advances in diatomaceous soil research are laconic and mainly oriented towards understanding the primary soil response (typical characterization methods) considering observation and experience (failures in construction processes or unexpected laboratory results) more than following a scientific method. Coincident results have been evidenced in the correspondence between the content of frustules, the effective friction angle and the water retention capacity. However, the variables and processes that control some mechanical behaviors have yet to be documented in the literature, such as the level of fracturing of the frustules and its relation with interlocked behavior, compressibility and shear strength. In addition to the bibliographic background, SEM microscopy records are presented. These facilitate the understanding of the described phenomena. The images highlight the level of deterioration, the environment, the morphology and the pores present in diatoms of different origins. The morphology (as a function of the species) of intact or fractured frustules (depending on the stress record) affects the mechanical responses and volumetric variations of the diatomaceous deposits. Furthermore, this review presents some emerging research lines in diatomaceous soils, such as the subjection of structures to geotechnical centrifuge conditions, some constitutive models and the criteria for developing water retention curves. [ABSTRACT FROM AUTHOR]

Due to the current changes in mobility, lightweight design concepts continue to be of particular interest to the automotive industry. One form is the multi-material design, in which the advantageous properties of different materials are combined in one component. In this work, a component made of a steel sheet with stiffening structures of cast aluminum is considered. The joint is created by channel structures with undercuts on the surface of the steel sheet, into which the molten aluminum can flow. After solidification, an interlocking connection is created. The aim of this work is to investigate the influence of a bending operation on the surface structure before the die casting process. Numerical simulations and experimental validations were performed with different bending angles and radii as well as orientations between the channel structure and the punch. The results show that the undercuts on the outer radius are reduced by up to 75% by the bending operation, thus weakening the resulting joint. On the inner radius, the channel opening width narrows by up to 73% and can thus impede the filling with the melt. [ABSTRACT FROM AUTHOR]

Suckermouth armoured catfish (Loricariidae) are a highly speciose and diverse freshwater fish family, which bear upper and lower lips forming an oral disc. Its hierarchical organisation allows the attachment to various natural surfaces. The discs can possess papillae of different shapes, which are supplemented, in many taxa, by small horny projections, i.e. unculi. Although these attachment structures and their working mechanisms, which include adhesion and interlocking, are rather well investigated in some selected species, the loricariid oral disc is unfortunately understudied in the majority of species, especially with regard to comparative aspects of the diverse oral structures and their relationship to the ecology of different species. In the present paper, we investigated the papilla and unculi morphologies in 67 loricariid species, which inhabit different currents and substrates. We determined four papilla types and eight unculi types differing by forms and sizes. Ancestral state reconstructions strongly suggest convergent evolution of traits. There is no obvious correlation between habitat shifts and the evolution of specific character states. From handling the structures and from drying artefacts we could infer some information about their material properties. This, together with their shape, enabled us to carefully propose hypotheses about mechanisms of interactions of oral disc structures with natural substrates typical for respective fish species. [ABSTRACT FROM AUTHOR]

Weight reduction strategies are essential for the transportation sector to reduce greenhouse gas emissions or extend the range of electric vehicles. In the field of lightweight assembly strategies, multi-material design offers great potential. Joining materials typically used in the automotive sector, such as aluminum and steel, brings challenges as conventional processes such as fusion welding are unsuitable. Therefore, new technologies can extend the design options. In previous studies, a mechanical interlocking between cold-rolled surface structures with undercuts on a steel sheet and die-cast aluminum was presented. This method has now been extended to double-sided structures for more complex applications with a joint on both sheet surfaces. Numerical simulations and validation experiments were performed to investigate the manufacturing of the double-sided structures. Furthermore, the influence of the alignment of the upper and lower structures in relation to each other on the resulting structural geometry and the rolling forces were analyzed. More advantageous geometric parameters, e.g., 24% larger undercuts, and approx. 24.1% lower forming forces at 20% height reduction were observed for a shifted alignment. However, significantly higher wear of the structured rollers occurred in the corresponding experiments.

This paper analyzes the characteristics of acquisition of functions in the technical conditions of the centralized signal monitoring system and verifies the analysis results through on-site trial in specific projects. In this way, it seeks to find installation methods to greatly improve the product quality of the centralized signal monitoring system. Decentralized installation means installation nearby monitoring objects, this installation method will shorten the monitoring and acquisition wirings and reduce the safety risks. Preinstallation at the factory will advance the field wiring to the assembly and prefabrication stage, which improves accuracy and achieves standardization. The installation method combining these two has been proved to be an effective approach. [ABSTRACT FROM AUTHOR]

Reducing the weight of parts through lightweight designs impacts CO2 emissions, especially in the automotive and transportation sectors, which have significant fuel and electric energy consumption. Using multi-material design approaches, specific material properties can be combined to achieve effective lightweighting. Commonly used metals include aluminum, which is known for its high specific strength, and steel, which is valued for its strength and structural integrity. However, joining aluminum and steel presents challenges given their different thermophysical properties and the potential formation of brittle intermetallic phases, making common joining techniques like fusion welding unsuitable. In this study, a hybrid casting process for the production of a complex workpiece from dissimilar materials was investigated. Aluminum was die-cast around a steel sheet insert. Surface structures with undercuts on the steel sheet were applied through modified cold rolling, allowing molten aluminum to flow into the channels and interlock during solidification. It was found that elevated temperatures of the melt and tool were beneficial for the interlocking, resulting in a 30% increase in compound strength. Furthermore, a reduction in both the piston position at the changeover point, between the pre-filling and cavity filling, and the melt velocity at the gate reduced the compound's strength by 41% and 30%. Up- and downstream processes did not show any significant influence on the conducted experiments. Based on this, two main detrimental effects were observed: pre-solidification of the aluminum melt and gas entrapment. [ABSTRACT FROM AUTHOR]

This paper presents a new gripping technique that merges the variable stiffness characteristics of conventional magnet-controlled and negative-pressure spherical grippers to produce a spherical gripper capable of securely grasping large and structurally diverse objects. The proposed method incorporates the smart rheological material from magnet-controlled grippers with the particle-jamming smart structure used in negative-pressure grippers. The gripper comprises a magnetic control device and a spherical variable stiffness body. Simulation analysis was used to optimize its structure and enhance the efficiency ratio of the magnetic control device. The flexible variable stiffness body was initially designed to be cylindrical to increase interlocking with objects. Experiments were conducted to evaluate the gripping efficiency and adaptability of the magnetron spherical gripper, which were designed to simulate real-world application requirements. These results suggest that the magnetically controlled spherical gripper can achieve a gripping efficiency of approximately five and securely grasp objects with a relative bladder diameter ranging from 20 % to 130 %. Furthermore, it can stably grip objects up to an offset distance of 15 mm without requiring sensor assistance. The enhanced magnetic field-powered spherical gripper exhibits superior adaptability and efficiency in gripping compared to its counterpart. In addition, it boasts robust resistance against environmental interference.

Studies show that the shear strength of angular-shaped calcareous sand is mainly affected by dilatancy, interparticle locking, and particle breakage. In the present study, a series of consolidated-drained triaxial compression tests on calcareous sands are carried out to investigate the strength impacts of dilatancy, interparticle locking, and particle breakage. It is found that as the stress level increases, the friction angle difference reflecting the effect of the particle breakage increases. In contrast, the friction angle difference reflecting the interparticle locking and dilatancy effect decreases gradually. Moreover, the critical stress ratio of the high-angled calcareous sands decreases, which may be attributed to particle breakage. The obtained results demonstrate that when the stress level exceeds a certain value, the critical stress ratio remains constant. Then the correlation between the particle breakage, interparticle locking, and dilatancy effects in the shear strength is studied. Finally, based on the performed analysis on energy dissipation in calcareous sands, a dilatancy model is proposed that covers the particle breakage effect. The performed analyses demonstrate that the proposed model can accurately explain the experimental data. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] Colloidal particles can be trapped at a liquid interface, which reduces the energetically costly interfacial area. Once at an interface, colloids undergo various self-assemblies and structural transitions due to shape-dependent interparticle interactions. Particles with rough surfaces receive increasing attention and have been applied in material design, such as Pickering emulsions and shear-thickening materials. However, the roughness effects on the interactions at a liquid interface remain less understood. Experimentally, particles with four surface roughnesses were designed and compared via isotherm measurements upon a uniaxial compression. At each stage of the compression, micrographic observations were conducted via the Blodgett method. Numerically, the compression of monolayer was simulated by using Langevin dynamics. Rough colloids were modelled as particles with capillary attraction and tangential constraints. Sufficiently rough systems exhibit a non-trivial intermediate state between a gas-like state and a close-packed jamming state. This state is understood as a gel state due to roughness-induced capillary attraction. Roughness-induced friction lowers the jamming point. Furthermore, the tangential contact force owing to surface asperities can cause a gradual off-plane collapse of the compressed monolayer. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Formal methods are mathematically based techniques for the rigorous development of software-intensive systems. The railway signaling domain is a field in which formal methods have traditionally been applied, with several success stories. This article reports on a mapping study that surveys the landscape of research on applications of formal methods to the development of railway systems. Following the guidelines of systematic reviews, we identify 328 relevant primary studies, and extract information about their demographics, the characteristics of formal methods used and railway-specific aspects. Our main results are as follows: (i) we identify a total of 328 primary studies relevant to our scope published between 1989 and 2020, of which 44% published during the last 5 years and 24% involved industry; (ii) the majority of studies are evaluated through Examples (41%) and Experience Reports (38%), while full-fledged Case Studies are limited (1.5%); (iii) Model checking is the most commonly adopted technique (47%), followed by simulation (27%) and theorem proving (19.5%); (iv) the dominant languages are UML (18%) and B (15%), while frequently used tools are ProB (9%), NuSMV (8%), and UPPAAL (7%); however, a diverse landscape of languages and tools is employed; (v) the majority of systems are interlocking products (40%), followed by models of high-level control logic (27%); and (vi) most of the studies focus on the Architecture (66%) and Detailed Design (45%) development phases. Based on these findings, we highlight current research gaps and expected actions. In particular, the need to focus on more empirically sound research methods, such as Case Studies and Controlled Experiments, and to lower the degree of abstraction, by applying formal methods and tools to development phases that are closer to software development. Our study contributes with an empirically based perspective on the future of research and practice in formal methods applications for railways. It can be used by formal methods researchers to better focus their scientific inquiries, and by railway practitioners for an improved understanding of the interplay between formal methods and their specific application domain. [ABSTRACT FROM AUTHOR]

Background and Objectives: Intramedullary interlocking nailing is currently considered the treatment of choice foropen(grade 1 and grade 2)tibial shaft fractures, with high rates of fracture union, advantages of early stabilization which decreases the morbidity and mortality rates in patients, allows early mobilization, reduces the incidence of infection, malunion, nonunion, or implant failure. This study is done to assess compound diaphyseal fractures of tibia and to evaluate the functional outcome of patients with open tibial shaft fracture treated with locked intramedullary nailing without reaming. Methods: Twenty adult patients of both sexes presented with open tibial shaft fractures to Princess Esra Hospital, Deccan College of medical sciences, Hyderabad who satisfies our inclusion criteria and are surgically fit are included in this study. All enrolled Patients were admitted from March 2020 to December 2021 were treated surgically with locked intramedullary interlocking nailing tibia without reaming and evaluated. Final assessment of functional outcome is done using JOHNER and WRUH'S Criteria. Results: The results of interlocking nail for fracture tibia without reaming were excellent in 15 patients (75%), good in 3 patients (15%) and fair in 2 patients (10%). The average healing time was 20.13 weeks. In our study valgus deformity of 3 degrees (3 patients) and varus deformity of 3 degrees (1 patient) is seen. There were 1 superficial infection (5%), 2 patients with anterior knee pain (10%), 1 patient with delayed union (5%) and 1 patient with shortening of 1cm seen (5%). Conclusion: The method of treatment employing closed intramedullary interlocking nailing without reaming to stabilize open (type 1 and type 2) diaphyseal fractures of tibia is ideal because of its excellent and good results. The method has a long learning curve but with the excellent results. The advantages of rapid rehabilitation and relatively few complications serve to recommend it for wider use. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the bonding mechanism during laser transmission welding of polycarbonate sheets using an electrolytic iron powder (EIP) absorber. The experiments are performed at different scan speeds and laser powers. The mechanical strength is determined by the lap shear test. The influence of line energy, interface temperature, and absorptivity on weld strength is discussed. The weld characteristics, bond morphology, and elemental distribution at the cross-section and fracture interface of the welded samples are analyzed. The results show that the maximum breaking strength of 1180 N is obtained at the 400 mm/min scan speed and 100 W laser power. The iron particles are observed mechanically interlocked at the lowest line energy with partial chemical bonding. However, the chain diffusion and chemical bonding have been increased with line energy. Thermal degradation and burning of the polycarbonate at the interface restrict the bonding and reduces the weld strength. [ABSTRACT FROM AUTHOR]

Two forms of symmetry which plane patterns can possess are the traditional wallpaper symmetries and the counterchange symmetries enumerated by H.J. Woods. Intermeshed crochet is a technique which may possess not only plane symmetries, but symmetries relating the back of the work to the front of the work. We explore how each of these new symmetries are realizable, in what combinations they can be realized within a single work, and how many ways each symmetry can be realized. [ABSTRACT FROM AUTHOR]

In the geotechnical area, advances in diatomaceous soil research are laconic and mainly oriented towards understanding the primary soil response (typical characterization methods) considering observation and experience (failures in construction processes or unexpected laboratory results) more than following a scientific method. Coincident results have been evidenced in the correspondence between the content of frustules, the effective friction angle and the water retention capacity. However, the variables and processes that control some mechanical behaviors have yet to be documented in the literature, such as the level of fracturing of the frustules and its relation with interlocked behavior, compressibility and shear strength. In addition to the bibliographic background, SEM microscopy records are presented. These facilitate the understanding of the described phenomena. The images highlight the level of deterioration, the environment, the morphology and the pores present in diatoms of different origins. The morphology (as a function of the species) of intact or fractured frustules (depending on the stress record) affects the mechanical responses and volumetric variations of the diatomaceous deposits. Furthermore, this review presents some emerging research lines in diatomaceous soils, such as the subjection of structures to geotechnical centrifuge conditions, some constitutive models and the criteria for developing water retention curves.

Copyright of Turkish Journal of Trauma & Emergency Surgery / Ulusal Travma ve Acil Cerrahi Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Interlocking refers to a kind of resistance caused by the staggered arrangement of granular materials. In geotechnical engineering, it is considered as one of the important sources of the shear strength of granular materials. Based on series of DEM simulations with varying particle shapes, the influences of interlocking on the mechanical behavior of granular soils are investigated in this paper, and the competition mechanism between dilation and interlocking in granular soils is discussed. A unified interlocking model is then proposed to characterize the influence of interlocking on mechanical response of granular sand with different densities, and a comprehensive interlocking parameter S is introduced to relate interlocking with yielding as well as dilation. Finally, a modified constitutive model is proposed considering the effect of interlocking within the framework of the bounding surface. And the predicted results using the proposed model have a good agreement with triaxial tests data for different sands with varying particle shapes. [ABSTRACT FROM AUTHOR]

The mechanical behavior of the interfaces between fine sea sand and offshore structure is regarded as a quite important issue that influences the foundation-bearing capacity and structural safety. In this work, by employing a modified shear apparatus with a ring-transparent sample container, a series of interface shear tests were conducted to shed light on the effects of the applied normal stress, initial relative density, and the roughness of the steel surface. Based on image analysis, the horizontal deformation at various vertical positions within the sand specimen was captured. In addition, the postshearing particle-size distributions of sand specimens were measured and compared. From the acquired test results, it was demonstrated that for the dense and medium dense sand–steel interfaces, strain softening is a typical shear behavior, regardless of the roughness of the steel surface. The mobilized shear stress of the interface with a smooth steel surface reaches the peak strength earlier than that of the rough one and then rapidly declines to residual strength within a short softening stage. The shearing zone in sand specimens can be divided into a large deformation zone and a small deformation zone. The shear deformation that occurs within the sand specimens sheared against the smooth steel surface is negligible and concentrated very close to the interface. However, for rough surface and dense sand, the interlocking between sand and steel forces the deformation of sand specimens to arise in greater scope and magnitude, accompanied by significant particle crushing. [ABSTRACT FROM AUTHOR]

Entirely grouted cable tendons are commonly used in mining engineering. They have superior working ability in reinforcing the excavated rocks and soils. During the working process of cable tendons, the force-transferring ability and the corresponding mechanism are significant in guaranteeing the safety of underground openings. To further understand the force-transferring mechanism of entirely grouted cable tendons, this paper provided a literature review on the force transfer of cable tendons. First, the force-transferring concept of entirely grouted cable tendons was summarised. The force-transferring process and failure modes of cable tendons were illustrated. Then, the experimental test program used in testing the entirely grouted cable tendons was summarised. The advantages and disadvantages of various test programs were illustrated. After that, the working ability of entirely grouted cable tendons was reviewed. The effect of various parameters on the working ability of cable tendons was summarised and compared. These parameters include the rock stiffness, embedment length, cement grout property, resin grout property, modified geometry, borehole size, rotation and pre-tensioning. Last, a discussion was provided to elaborate the working ability and force-transferring mechanism of entirely grouted cable bolts. This literature review is beneficial for researchers and engineers, furthering their understanding of the working ability of cable tendons. [ABSTRACT FROM AUTHOR]

Interlocking Concrete Block Pavement (ICBP) is a special type of pavement with a unique load spreading mechanism due to the discrete wearing layer. There is a lack of design procedure and design charts for the ICBP in India, as reported by the IRC SP 63 [2018. Guidelines for the use of interlocking concrete block pavement. New Delhi: Indian Road Congress] specification. The objective of the present study is to develop a design procedure for ICBP which complies Indian standards specification. The study also aimed to develop the deflection model and combined elastic modulus model for ICBP wearing layer considering the geometric properties of ICBP based on laboratory and numerical studies. The design procedure was then formulated considering the deflection of the pavement section and the rutting of the subgrade. The proposed design procedure was validated with the ICBP design section of ASCE58-10 [2010. Structural Design of Interlocking Concrete pavement for municipal streets and roadways. American Society of Civil Engineers] developed by ASCE (American Society of Civil Engineers) and ICPI (Interlocking Concrete Pavement Institute). The study finally arrived in developing a design chart and design software named NITT-BLOCKPAVE, which is programmed based on the proposed design procedure for the ICBP pavement section. [ABSTRACT FROM AUTHOR]

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Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current mechanisms and factors influencing soil aging remain inconclusive and incomplete. Discrete element method (DEM) is adopted to investigate the responses of irregularly shaped granular assemblies subjected to creep and post-creep triaxial shear. The simulated creep and aging behaviours are generally in line with those observed in existing laboratory tests and numerical investigations. In addition to an increase in soil stiffness, the DEM analyses predict an enhanced soil strength as a result of the prolonged interlocking between sand particles during the relatively long creep duration. It is demonstrated that the creep-induced interlocking is directly manifested as a shear resistance above the minimum energy line. The development of interlocking explains the overshooting behaviour observed in post-creep shear. The microscopic responses do not support the aging mechanism based on the buckling of strong force chains. A new hypothesis, termed 'microstructure evolution by stability selection', is proposed to explain soil aging. This hypothesis suggests that interlocking between particles develops naturally during the creep process because interlocked particle clusters generally have a greater chance to survive the particle rearrangement induced by creep, leading to an increased number of interlocked particle clusters in aged soils. [ABSTRACT FROM AUTHOR]

Combining interlocking structures and gradient design, this paper proposes a 2D biomimetic nacreous composite material with a gradient interlocked structure. Experimental and numerical simulation methods are employed to investigate the initiation and propagation behavior of cracks in the regular interlocking and gradient interlocked biomimetic nacreous composite materials. Samples of biomimetic nacreous composite materials with pre-existing cracks are manufactured using 3D printing technology, and uniaxial tensile tests are conducted to explore their crack propagation behavior. For biomimetic nacreous composite materials with periodic interlocking structures, the interlocking angle is found to play an important role in the toughening mechanism of composites. In biomimetic composite materials with large interlocking angles, crack inhibition effects are achieved through structural gradient design, effectively preventing catastrophic failure. Within the numerical analysis framework, a cohesive zone modeling approach is employed to represent the softer phase of the material, and the numerical simulation are validated by direct comparison with experimental results. In addition, a comprehensive numerical analysis is carried out to comprehend how the structural gradient affects the spread of cracks in these nacreous composites. This research not only illuminate the underlying deformation and toughening mechanisms intrinsic to interlocking nacreous composites but also pave the way for innovative strategies in the design of biomimetic materials through the incorporation of structural gradients. [ABSTRACT FROM AUTHOR]

Reducing the weight of parts through lightweight designs impacts CO2 emissions, especially in the automotive and transportation sectors, which have significant fuel and electric energy consumption. Using multi-material design approaches, specific material properties can be combined to achieve effective lightweighting. Commonly used metals include aluminum, which is known for its high specific strength, and steel, which is valued for its strength and structural integrity. However, joining aluminum and steel presents challenges given their different thermophysical properties and the potential formation of brittle intermetallic phases, making common joining techniques like fusion welding unsuitable. In this study, a hybrid casting process for the production of a complex workpiece from dissimilar materials was investigated. Aluminum was die-cast around a steel sheet insert. Surface structures with undercuts on the steel sheet were applied through modified cold rolling, allowing molten aluminum to flow into the channels and interlock during solidification. It was found that elevated temperatures of the melt and tool were beneficial for the interlocking, resulting in a 30% increase in compound strength. Furthermore, a reduction in both the piston position at the changeover point, between the pre-filling and cavity filling, and the melt velocity at the gate reduced the compound’s strength by 41% and 30%. Up- and downstream processes did not show any significant influence on the conducted experiments. Based on this, two main detrimental effects were observed: pre-solidification of the aluminum melt and gas entrapment.