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Unprecedented mechanical properties of the novel TWIP/TRIP titanium alloys are controlled by [Formula: see text][Formula: see text] twinning and stress-induced martensitic transformation, which can operate separately, simultaneously or even in synergy, following a still unclear atomic-scale mechanism. Using ab initio calculations and experimental observations, we show that [Formula: see text][Formula: see text] twinning can be described as a polymorphic solid-state transformation able to produce either twinned or martensitic structures with a unified transformation path. The required lattice strains and atomic shuffles are provided by the shear-shuffle mechanism of twin operation, of which trajectory, due to accompanied atomic relaxation, is not linear and strongly influenced by β phase stability.

This study investigates the effect of Mn on the microstructure and mechanical properties of Stellite 21 cobalt-based coatings prepared by laser cladding on 24CrNiMo steel substrates, focusing on utilizing the Transformation-Induced Plasticity (TRIP) mechanism to enhance toughness and thermal fatigue performance. The results indicate that the microstructure of the Stellite 21 alloy coating is primarily composed of γ-Co (FCC) with a minor presence of ε-Co (HCP), M 23 C 6 , and M 7 C 3 carbides, which predominantly precipitate at or near the grain boundaries. Upon the addition of Mn, it dissolves into the γ-Co matrix, causing lattice distortion and increasing dislocation density, thereby contributing to solid solution strengthening. Compared to the Mn-free Stellite 21 alloy coating, the coating with 5 % Mn exhibits an approximately 21 % increase in tensile strength (∼1135 MPa) and a 74 % increase in elongation (∼14.5 %). This improvement is mainly attributed to the solid solution strengthening caused by lattice distortion due to Mn addition and the synergistic enhancement from the TRIP mechanism facilitated by the lower stacking fault energy. Moreover, the thermal fatigue crack propagation rate in the coating with 5 % Mn is reduced by approximately 42.5 % compared to the Mn-free Stellite 21 alloy coating. The enhancement in thermal fatigue performance is primarily due to the Mn addition, which stabilizes the ε-Co phase during thermal fatigue processes, enhancing plastic deformation capacity. The phase transformation process alleviates stress concentration, effectively reducing crack propagation rates and ultimately improving the material's thermal fatigue performance. [ABSTRACT FROM AUTHOR]

The applicability of metastable β titanium alloys is frequently constrained by their relatively low yield strength. This study has successfully designed a metastable β titanium alloy with heterogeneous microstructures (HS) comprising both deformed and recrystallized grains, achieved through simple cold rolling followed by short-term annealing. Compared to traditionally coarse-grained (CG) specimen that is entirely crystallized and equiaxed, the HS specimen exhibit not only a postponed initiation of double yielding but also superior yield strength (enhanced by 27.8 %) and ductility (enhanced by 7 %). The delayed double yielding and enhanced strength in the HS specimen are ascribed to the restriction of dislocation motion by α" martensite and the heterogeneous deformation induced (HDI) strengthening mechanisms. The ductility of the HS specimen exceeds that of the CG specimen, owing to the combined effect of HDI hardening and the transformation-induced plasticity (TRIP) effects. The more pronounced TRIP effect in the HS specimens results from the synergistic effect of the elevated HDI stress and the applied external stress, which promotes the occurrence of stress-induced martensitic phase transformation. This study offers a novel strategy for the development of high-performance metastable β titanium alloys. [ABSTRACT FROM AUTHOR]

This study produces a Ni-containing ductile iron with a matrix consisting of lamellar α and γ phases, along with nanoscale Mg 6 Si 7 Ni 16 phases. The interface of fine α and γ phases and the nanoscale Mg 6 Si 7 Ni 16 phases impede dislocation mobility, contributing to high yield strength. During the tensile test, the transformation-induced plasticity (TRIP) phenomenon is etected because Ni addition effectively endows appropriate carbon concentration in γ phase of ductile iron. The TRIP effect significantly augments the strain-hardening capacity of ductile iron, resulting in an excellent plasticity with an elongation of ∼21 % and a considerable ultimate tensile strength of ∼900 MPa. Consequently, the ductile iron achieves an exceptional strength-plasticity synergy, characterized by the product of tensile strength and elongation (PSE) of 19 GPa%. [Display omitted] • A ductile iron composed of graphite, lamellar α and γ phases was produced. • Nanoscale Mg 6 Si 7 Ni 16 phases were observed in the tempered sample. • TRIP effect was observed during the deformation of the tempered sample. • An excellent strength and plasticity with a PSE of 19 GPa% was obtained. [ABSTRACT FROM AUTHOR]

Metallic materials or alloys consisting of single face-cubic centered (FCC) phases typically face difficulties in obtaining high strength without sacrificing ductility. The introduction of different crystalline defects via pre-straining and the activation of multiple deformation mechanisms have been shown to be effective in achieving superior strength–ductility synergy. In this work, we investigated the role of varying rolling conditions and subsequent annealing on the mechanical response in an established twinning- and transformation-induced plasticity dual phase high-entropy alloy (TWIP-TRIP-DP HEA). We found that all of the annealed samples exhibited similar nano-twinned structures. Furthermore, phase transformation from FCC γ to hexagonal close-packed (HCP) ε prevailed along the nano-twins under mechanical loading. With increasing rolling temperature, the phase stability of the matrix revealed a downward trend, resulting in a significant increase in TWIP/TRIP effects along with a prominent change in the deformation microstructure. Our study presented a simple and feasible strategy for manipulating mechanical performance by modulating the microstructural characteristics and associated deformation modes. [Display omitted] • Metastable Fe 50 Mn 30 Co 10 Cr 10 C 0.5 high-entropy alloys with single FCC matrix are successfully fabricated. • The structural stability can be adjustable by altering rolling temperature. • The origins for fantastic mechanical properties together with good work-hardening capability were elucidated. [ABSTRACT FROM AUTHOR]

With the surge of electric vehicles, accurate estimation of their energy consumption becomes increasingly critical. Data-driven models have been widely used for estimating the energy consumption of electric vehicles; however, their applications often face limitations due to inadequate training data, resulting in over-fitting and poor generalizability. In this paper, a physically rational data augmentation approach is proposed to expand the driving trip dataset. By incorporating physical coherence into the augmentation process, new driving trips are synthesized with rational physical context. The effectiveness of the proposed approach is validated by applying it to three data-driven models for estimating the energy consumption of electric vehicles across different validation scenarios. Compared with two baseline data augmentation approaches, our proposed approach demonstrates superior model training performance with less data synthesized. In the best case, the proposed approach achieved a 34% accuracy improvement over the raw data and an 11% improvement over the best-performing baseline. This proposed approach shows considerable promise in facilitating the effective adoption of advanced machine learning algorithms in industrial applications by significantly reducing the data collection requirements. [Display omitted] • The requirements of small-scale data for BEV data-driven models are discussed. • An approach that synthesizes physically rational BEV trip samples is proposed. • Experiments show that conventional data augmentation may produce invalid samples. • The proposed approach effectively improves the performance of data-driven models. [ABSTRACT FROM AUTHOR]

The mechanical performance and multi-step TRIP/TWIP behaviors in a metastable Fe 55 Mn 25 Co 10 Cr 10 were systematically investigated at room temperature (RT) and 77 K. The deformation behaviors and mechanically induced ε-martensite, fcc twin and hcp twin bands in Fe 55 Mn 25 Co 10 Cr 10 were studied based on the thermodynamics and nanostructural analyses. Deformation-induced nanostructural evolutions were found to vary greatly as the temperture decreases from RT to 77K. Deformation induced ε-martensite and fcc deformation twins (fcc) carrying more strain developed at RT. On the other hand, bi-directional ε-martensite bands were favored to accommodate the increased strain at 77K instead of fcc deformation twins because of the increased stability of hcp phase. Complicated hcp ε-martensite twins developed adjacent to the crossed region of two ε-martensitec bands at 77K. The tensile stress developed perpendicular to the original hcp ε-martensite band because of its intrinsic smaller c/a ratio (1.615–1.620) than the ideal ratio (1.633) in hcp ε-martensite, inducing {10Ī2} twins with (0001) basal plane approximately perpendicular (86.0°) to that of the original ε-martensite band. Hcp twinning in the ε-martensite band at 77K is suggested to be driven by the structural and electronic relaxations associated with the c/a distortion of the hcp ε-martensite bands. Excellent strength-ductility combinations were also obtained at RT (861MPa/73.2 %) and 77 K (1.42GPa/61.8 %) because of the enhanced hardening rates due to TRIP/TWIP(fcc) at RT and/or TRIP/TWIP(hcp) at 77 K in this study. [ABSTRACT FROM AUTHOR]

Additively-manufactured metastable high entropy alloys are emerging as promising alternatives for energy absorption in protective equipment due to their exceptional ductility. In this study, an elongation of over 50 % was achieved in a directed energy deposition fabricated Fe 45 Mn 35 Co 10 Cr 10 metastable high entropy alloys (MHEAs). The inherent high cooling rate and repeated heat treatment in the directed energy deposition process were harnessed to deliberately induce an uneven distribution of Mn elements, forming a cellular structure with chemical boundary. The unique heterogeneity stacking fault energy results in a synergistic interplay of multiple deformation mechanisms such as, dislocation slip, transformation-induced plasticity (TRIP) and twinning-induced plasticity (TWIP). In the initial stage of deformation, dislocation slip and TRIP contribute to the main plasticity. Stacking faults/martensite are confined within the cellular structure with low stacking fault energy (SFE). As strain increases, TWIP and TRIP are activated in the high SFE regions. Twins and martensite across the cell wall were observed. As strains exceed 40 %, primary martensite variant and twinning with a particular intersection angle take place to further enhance the deformation ability. The chemical boundary with stacking fault energy heterogeneity not only simultaneously activates both TRIP and TWIP, but also maintains the martensite and twins at the nanoscale. • Fe 45 Mn 35 Co 10 Cr 10 MHEAs were manufactured by DED with high ductility. • The uneven distribution of Mn elements results in stacking fault energy heterogeneity. • The stacking fault energy heterogeneity enables the simultaneous activation of TRIP and TWIP. • Chemical discontinuity maintains the width of martensite and twins consistently at the nanoscale. • Monoclinic structure MnO particles do not influence the TRIP/TWIP processing. [ABSTRACT FROM AUTHOR]

Internal combustion engines contribute significantly to global warming and air pollution in urban areas with high population densities and abundant vehicular movement. Alternative energy vehicle, such as hybrid and electric vehicles, are being developed to address these concerns. However, a gradual transition to electrification while maintaining the existing fuel infrastructure appears more feasible than the rapid proliferation of battery-powered electric vehicles. Hybrid electric vehicles are recognized as an important means of improving vehicle fuel efficiency and reducing carbon emissions by introducing changes in driving modes to enhance energy consumption efficiency. Catalyst activation does not occur in cold starts, making it challenging to control exhaust emissions. In Korea, urban driving patterns characterized by speeds below 60 km/h often results in insufficient catalyst activation. Therefore, research on the characteristics of urban driving and cold-start conditions is essential. This study analyzed the urban driving characteristics of domestic hybrid vehicles reflecting urban conditions through chassis tests and examined the variations in the external temperature and engine contribution to assess the control capability of the hybrid system. Confirming that minimizing the engine preheating time during cold starts and efficiently utilizing energy stored in the motor can enhance fuel efficiency and reduce exhaust emission rates. • Fuel consumption and exhaust emissions are predominantly generated during vehicle operation. • Hybrid electirc vehicles have the best fuel efficiency. • The hybrid system is controlled and operated by the state of charge. • Enhancing both fuel efficiency and emission control is achieved through hybrid systems. [ABSTRACT FROM AUTHOR]

In this comprehensive study, the multifaceted impact of laser surface texturing (LST) on AISI 301LN stainless steel is explored. Changes in the microstructure, mechanical properties, and grain characteristics are examined. The dynamic relationship between Schmid factor evolution and plastic deformation in this stainless steel alloy is unveiled through the analysis of grain statistics and individual grain scrutiny. It is revealed that LST initiates the formation of strain-induced α’-martensite, grain refinement, and substantial hardness enhancements. Notably, an α’-martensite crystalline size of 2.05 Å is induced by LST. Furthermore, a 12% increase in tensile strength is observed after LST along with an 11% boost in yield strength. However, reductions of 19% in elongation to fracture and 12% in the area reduction are experienced.

This study aims to analyze the effect of thermo mechanical coupling damage in the presence of a phase change (austenite/martensite) in 35NCD16 steel. The impact of increasing mechanical traction load, accompanied by a martensitic transformation on the scale of a single grain with boundary has been studied. The prediction transformation of induced plasticity (TRIP) was evaluated by taking into account the following parameters: twenty shear directions of the martensitic plates, two values of the shear deformation of the martensitic plates, energetic and thermodynamics criteria for getting in order the transformation of the martensitic plates, elastoplastic behavior of the two areas in the first case (martensitic plate and grain boundary) and elastic behavior for the grain boundary in the second case. The numerical calculation is carried out using the finite element method (FEM), implemented in the Zebulon calculation code. The developed approach is validated using the available experimental results reported in the literature. The numerical results showed that the estimation of TRIP given by the energetics criteria with the values of the shear deformation (?0 = 0.16) are closer to the experiment results.

The socio-economic characteristics of individual and group have been found to significantly have an impact on their mobility and travel behaviour. Hence, this study examined the influence of socio-economic characteristics of households in the Rural areas of Nigeria on trip making. The study adopted the multi-stage sampling technique method where 12, 365 registered buildings were systematically selected out of a total of 28,341 buildings. Systematic sampling technique was used to survey 4 percent of households, representing 495 household heads of a total 12,365 registered buildings by means of questionnaire administration. The study revealed that majority of the respondents were between the age of 60–69 years and utilized the non-motorized (walk & bicycle) means of transport. The result of the multiple regression analysis further revealed that Age and Income were the significant socio-economic variables influencing trip making of households. This study thus advocates the influence of demographic attributes on households' travel behaviour. Therefore, rural communities should be given equal privilege as urban areas when formulating transport policies as a result of their unique and distinct socio-economic attributes. [ABSTRACT FROM AUTHOR]

There is significant evidence from light metals that turbulence in casting leads to bifilm defects; enfolded, doubled-over oxide films which act like cracks in the liquid, and are inherited as cracks by the solid. This population of introduced cracks is now known to significantly influence the tensile failure behaviour of light alloys. There is evidence that analogous defects exist in steels. This paper examines the possibility that bifilms may control the hot ductility of TWIP and TRIP steels, and therefore the problems of straightening during continuous casting. Techniques for overcoming these problems are indicated. [ABSTRACT FROM AUTHOR]

Copyright of TST - Transportes, Servicios y Telecomunicaciones is the property of Asociacion Iberica de Historia Ferroviaria 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 protein known as PI3K-interacting protein (PIK3IP1), or transmembrane inhibitor of PI3K (TrIP), is highly expressed by T cells and can modulate PI3K activity in these cells. Several studies have also revealed that TrIP is rapidly downregulated following T cell activation. However, it is unclear how this downregulation is controlled. Using a novel monoclonal antibody that robustly stains cell-surface TrIP, we demonstrate that TrIP is lost from the surface of activated T cells in a manner dependent on the strength of signaling through the T cell receptor and specific downstream signaling pathways, in particular classical PKC isoforms. TrIP expression returns by 24 h after stimulation, suggesting that it may play a role in resetting T cell receptor signaling at later time points. We also provide evidence that ADAM family proteases are required for both constitutive and stimulation-induced downregulation of TrIP in T cells. Finally, by expressing truncated forms of TrIP in cells, we identify the region in the extracellular stalk domain of TrIP that is targeted for proteolytic cleavage., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The article discusses and systematizes the causes of high values of short-circuit currents in electrical networks up to 1 kV and indicates their negative consequences. A brief analysis of some current limiting methods (both with and without additional investment) is given, which makes it possible to reduce the negative effects when significant short-circuit currents occur. The variants of the implementation of these current limiting methods recommended for study at the design stage or when replacing equipment that has exhausted its resource, are considered. The advantages and disadvantages of the methods of limiting short-circuit currents described in the article are indicated. Options for connecting equipment with low power consumption to nodes of the electrical network up to 1 kV with high values of short-circuit currents are also considered. Special attention is paid to current-limiting protection devices, a detailed description of the design of some of them is given, the advantages of their use in comparison with other current-limiting methods are indicated, the corresponding graphs of the limitation of the periodic component of the short-circuit current, shock short-circuit current and thermal pulse are presented. Based on the analysis of graphic materials, the issue of ensuring the selectivity of protections is considered. The degree of prevalence of equipment with the property of current limitation is determined. A method for determining selective current-limiting protection devices is given, viz. the method of energy selectivity, the corresponding graphs for determining energy selectivity are presented. The physics allowing to determine the degree of efficiency of limiting the short-circuit current is described. Recommendations on the use of current-limiting equipment are proposed.

Resumen Este artículo propone un análisis del libro Viajes. De la Amazonia a Malvinas (2014) de Beatriz Sarlo, en las distintas disposiciones en que aparecen la experiencia, los saberes y la comprensión. Abstract This article proposes an analysis of Beatriz Sarlo's book Viajes. De la Amazonia a Malvinas (2014), in the different dispositions in which experience, knowledge and understanding appear.

Background: Transfemoral prosthesis users' high fall rate is related to increased injury risk, medical costs, and fear of falling. Better understanding how stumble conditions (e.g., participant age, prosthesis type, side tripped, and swing phase of perturbation) affect transfemoral prosthesis users could provide insight into response deficiencies and inform fall prevention interventions.Methods: Six unilateral transfemoral prosthesis users experienced obstacle perturbations to their sound limb in early, mid, and late swing phase. Fall outcome, recovery strategy, and kinematics of each response were recorded to characterize (1) recoveries versus falls for transfemoral prosthesis users and (2) prosthesis user recoveries versus healthy adult recoveries.Results: Out of 26 stumbles, 15 resulted in falls with five of six transfemoral prosthesis users falling at least once. By contrast, in a previously published study of seven healthy adults comprising 214 stumbles using the same experimental apparatus, no participants fell. The two oldest prosthesis users fell after every stumble, stumbles in mid swing resulted in the most falls, and prosthesis type was not related to strategy/fall outcomes. Prosthesis users who recovered used the elevating strategy in early swing, lowering strategy in late swing, and elevating or lowering/delayed lowering with hopping in mid swing, but exhibited increased contralateral (prosthetic-side) thigh abduction and trunk flexion relative to healthy controls. Falls occurred if the tripped (sound) limb did not reach ample thigh/knee flexion to sufficiently clear the obstacle in the elevating step, or if the prosthetic limb did not facilitate a successful step response after the initial sound-side elevating or lowering step. Such responses generally led to smaller step lengths, less anterior foot positioning, and more forward trunk flexion/flexion velocity in the resulting foot-strikes.Conclusions: Introducing training (e.g., muscle strength or task-specific motor skill) and/or modifying assistive devices (e.g., lower-limb prostheses or exoskeletons) may improve responses for transfemoral prosthesis users. Specifically, training or exoskeleton assistance could help facilitate sufficient thigh/knee flexion for elevating; training or prosthesis assistance could provide support-limb counteracting torques to aid in elevating; and training or prosthesis assistance could help initiate and safely complete prosthetic swing. [ABSTRACT FROM AUTHOR]

Stroke survivors are at a relatively higher risk of falling than their healthy counterparts. To identify the key gait characteristics affecting fall risk in this population, this study analyzed the gait kinematics and gait asymmetries for 36 community-dwelling people with chronic stroke (PwCS). According to their fall history in the last 12 months, they were divided into a fall group (n = 21) and non-fall group (n = 15), and then the gait kinematics (step length, stride length, stance time, swing time, trunk angle, and segment angles for lower limbs) and their asymmetries (symmetry ratio and symmetry index) were compared between these two groups. To investigate the relationship between fall types and gait characteristics, these variables were also compared between 11 slip-fallers and non-fallers, as well as between 7 trip-fallers and non-fallers. Our results indicated that the fallers showed smaller trunk and thigh angle, larger shank angle, and higher gait asymmetries (trunk and foot). Such changes in gait pattern could also be found in the trip-fallers, except the trunk angle. Additionally, the trip-fallers also showed a shorter step length, shorter stride length, shorter swing time, larger foot angle on the paretic side, and higher asymmetries in shank angle and step length, while the slip-fallers only showed changes in trunk angle and thigh angle and higher asymmetries in step length and foot angle compared to the non-fall group. Our results indicated that improper or pathological gait patterns (i.e., smaller thigh angle or higher foot asymmetry) increases the risk of falling in PwCS, and different fall types are associated with different gait characteristics. Our findings would be helpful for the development of fall risk assessment methods that are based on kinematic gait measurements. Implementation of objective fall risk assessments in PwCS has the potential to reduce fall-related injuries, leading to a reduction in associated hospital costs. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) and medium-entropy alloys (MEAs), also sometimes referred to as multi-principal element alloys (MPEAs), present opportunities to develop new materials with outstanding mechanical properties. Through the careful selection of constituent elements along with optimized thermal processing for proper control of structure, grain size, and deformation mechanisms, many of the newly developed HEA systems exhibit superior strength and ductility levels across a wide range of temperatures, particularly at cryogenic deformation temperatures. Such a remarkable response has been attributed to the hardening capacity of many MPEAs that is achieved through the activation of deformation twinning. More recent compositions have considered phase transforming systems, which have the potential for enhanced strengthening and therefore high strength and ductility levels. However, the strain rate sensitivity of such transforming MPEAs is not well understood and requires further investigation. In this study, the tensile properties of the non-equiatomic V10Cr10Fe45Co30Ni5 MPEA were investigated at different deformation rates and temperatures ranging from 77 K (−196 °C) to 573 K (300 °C). Depending on the deformation temperature, the considered MPEA exhibits plasticity through either crystallographic slip, deformation twinning, or solid-state phase transformation. At 300 °C, only slip-mediated plasticity was observed for all the considered deformation rates. Deformation twinning was detected in samples deformed at room temperature, while face-centered cubic to body-centered cubic phase transformation became more favorable at cryogenic deformation temperatures. The trends are nonlinear with twinning-induced plasticity (TWIP) favored at the intermediate deformation rate, while transformation-induced plasticity (TRIP) was observed, although limited, only at the slowest deformation rate. For all the considered deformation rates at cryogenic deformation temperature, a significant TRIP activity was always detected. The extent of TRIP, however, was dependent on the deformation rate. Increasing the deformation rate is not conducive to TRIP and thus hinders the hardening capacity. [ABSTRACT FROM AUTHOR]

Current applications of the Internet of Everything (IOE) tend to ignore the components of people, processes, and data. In the current study, we propose applying the IOE to design, the core of which comprises people, processes, and data. Evidence of the positive effects of the IOE on design indirectly confirms the value of these three components. The selected case study was poster designs advertising personalized travel. We reported the process of how the system was created, followed by an actual simulation with the personalized poster design for the tourism promotion for the city of Tainan, Taiwan. This study created an IOE framework and applied relevant algorithms to collect data to target design issues. Data were collected, converted, and cleaned through multiple physical objects, internet resources, and output keywords, which were then provided to three designers with various backgrounds and styles. Posters were designed based on the keywords identified. As the targeted audience, 124 respondents were recruited to participate in a survey on the finished posters. Analysis of this feedback demonstrated the validity of the proposed framework. [ABSTRACT FROM AUTHOR]

This study aims to develop a valid and reliable "Teacher Anxiety Scale for Organizing Trips to Out of School Learning Environments" to measure teachers' anxiety about out-of-school learning environments. This research focuses on the methodological validity and reliability of the scale. The study group of the research consisted of 394 teachers working in public and private schools affiliated to the Ministry of National Education in different cities of Turkey. In the development of the scale, the processes of literature review, creating an item pool, obtaining expert opinion, pilot test, creating the trial form, data collection, data analysis (exploratory factor analysis, repeated exploratory factor analysis, confirmatory factor analysis, item analysis, and reliability analysis), and creating the final form were followed. As a result of the analysis, a valid and reliable scale consisting of 28 items and four factors was created. The factors of the scale were named "Bureaucracy-Related (BR) Anxiety", "Safety Risks-Related (SRR) Anxiety", "Harm-Related (HR) Anxiety" and "Pedagogy-Related (PR) Anxiety", respectively. While the Cronbach's Alpha reliability coefficient for the total scale was determined as .944; the reliability coefficients for the factors were determined as BR Anxiety Cr α=.868, SRR Anxiety Cr α=.922, HR Anxiety Cr α=.903, and PR Anxiety Cr α=.952, respectively. The results indicate that the scale is quite reliable. [ABSTRACT FROM AUTHOR]

Copyright of Runa: Archivo para las Ciencias del Hombre is the property of Runa: Archivo para las Ciencias del Hombre 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.)

Trip perturbations are proposed to be a leading cause of falls in older adults. To prevent trip-falls, trip-related fall risk should be assessed and subsequent task-specific interventions improving recovery skills from forward balance loss should be provided to the individuals at risk of trip-fall. Therefore, this study aimed to develop trip-related fall risk prediction models from one’s regular gait pattern using machine-learning approaches. A total of 298 older adults (≥60 years) who experienced a novel obstacle-induced trip perturbation in the laboratory were included in this study. Their trip outcomes were classified into three classes: no-falls (n = 192), falls with lowering strategy (L-fall, n = 84), and falls with elevating strategy (E-fall, n = 22). A total of 40 gait characteristics, which could potentially affect trip outcomes, were calculated in the regular walking trial before the trip trial. The top 50% of features (n = 20) were selected to train the prediction models using a relief-based feature selection algorithm, and an ensemble classification model was selected and trained with different numbers of features (1–20). A ten-times five-fold stratified method was utilized for cross-validation. Our results suggested that the trained models with different feature numbers showed an overall accuracy between 67% and 89% at the default cutoff and between 70% and 94% at the optimal cutoff. The prediction accuracy roughly increased along with the number of features. Among all the models, the one with 17 features could be considered the best model with the highest AUC of 0.96, and the model with 8 features could be considered the optimal model, which had a comparable AUC of 0.93 and fewer features. This study revealed that gait characteristics in regular walking could accurately predict the trip-related fall risk for healthy older adults, and the developed models could be a helpful assessment tool to identify the individuals at risk of trip-falls.

• In-situ tensile testing is performed up to failure under synchrotron X-ray diffraction. • Stress/strain level dependent strengthening mechanisms are exhibited in terms of diffraction peaks change. • The microstructure evolution, phase transformation, and strengthening mechanisms occurring during loading on a dual-phase high entropy alloy are detailed. The present research focuses on analyzing the deformation mechanisms associated with tensile loading of the Fe 50 Mn 30 Co 10 Cr 10 high entropy alloy (HEA) using synchrotron x-ray diffraction (SXRD). This novel material is comprised by two major phases: γ-FCC and ε-HCP, where transformation induced plasticity (TRIP) effectively transforms the first into the latter, upon the application of an external stress. However, the presence of thermally stable ε-HCP prior to loading will also influence the deformation mechanism of the material during mechanical solicitation. As such, here we investigate the activation of different strain accommodation mechanisms and the consequent microstructural evolution. Four stages were identified in the mechanical response of this novel HEA, where the TRIP and the twinning induced plasticity (TWIP) deformation modes are the main events granting this HEA its outstanding properties. Such sequence of events allows to evidence the effectiveness of the collaboration between the transformative capability of the γ-FCC phase and the work hardening potential of the ε-HCP phase. This analysis is performed via quantitative and qualitative analysis of the SXRD data, allowing also to investigate the response behavior of specific crystallographic planes to the increasing stress throughout the experiment. [Display omitted] [ABSTRACT FROM AUTHOR]

When the 34th sucker rod was set down into the well, the first tubing of the string was tripped from the mill end, and all the entire well's tubing and the sucker rods dropped into the well, the tubing was tripped three times during the salvage process, and all of them was tripped from the mill end. The specification of failed tubing was Φ73.02 mm × 5.51 mm J55 NU. To analyze the cause of the tubing failure, three groups of samples (failed tubing, new tubing and used tubing) were analyzed by means of mechanical characteristics, thread parameter inspection, microstructure analysis, and physical performance test. The results indicated: (1) the mechanical characteristics of failed tubing and new tubing met the standard requirements; (2) the thread parameters of the new tubing met the standard requirements, and there was no galling after makeup or breakout; (3) the strength of the thread connection after stretching to failure of the two groups of tubing that had not failed met the standard requirements, but the failure position was the mill end of the coupling; (4) the pitch fluctuation of the same axis of the new tubing and the outer thread of the failed tubing was obvious, indicating that the mill end thread of the tubing coupling was insufficient to bear the tensile load and had experienced a large plastic deformation during the tripping process; (5) combined with the three occasions of the mill end tripping of the tubing salvage, it was clear that the failure tubing was caused by a smaller makeup torque at the mill end of the tubing. As a result, the connection strength was relatively low, and the field tensile load surpassed the thread connection strength of the tubing mill end. [ABSTRACT FROM AUTHOR]

The uniaxial ratchetting behavior and cyclic softening/hardening characteristics of Fe‐0.4C‐7Mn‐3.2Al steel are revealed by cyclic loading experiments. Electron backscattered diffraction (EBSD) and X‐ray diffraction (XRD) analyses have been carried out for assessing retained austenite (RA) transformation during cyclic deformation. Fe‐0.4C‐7Mn‐3.2Al steel exhibits a gradual transition from cyclic stabilization to slight cyclic hardening with increasing strain amplitude. RA transformation is one of the reasons for cyclic hardening. The ratchetting of Fe‐0.4C‐7Mn‐3.2Al steel shows two different characteristics under asymmetrical cyclic stressing. When the stress amplitude is below a certain value, the ratchetting is similar to that of typical cyclic stabilized materials in three stages of deceleration, stabilization and acceleration. However, when the stress amplitude reaches a certain level, the ratchetting evolution accelerates from the beginning to the fracture. The results show that the interaction between transformation‐induced plasticity and ratchetting strain can lead to accelerated accumulation of plastic strain. Highlights: The uniaxial ratchetting behavior and cyclic softening/hardening characteristics of a medium manganese steel are revealed.The transformation of retained austenite (RA) during cyclic deformation is analyzed.The interaction between transformation induced plasticity and ratchetting can lead to accelerated accumulation of plastic strain. [ABSTRACT FROM AUTHOR]

Unprecedented mechanical properties of the novel TWIP/TRIP titanium alloys are controlled by { 332 } < 113 > twinning and stress-induced martensitic transformation, which can operate separately, simultaneously or even in synergy, following a still unclear atomic-scale mechanism. Using ab initio calculations and experimental observations, we show that { 332 } < 113 > twinning can be described as a polymorphic solid-state transformation able to produce either twinned or martensitic structures with a unified transformation path. The required lattice strains and atomic shuffles are provided by the shear-shuffle mechanism of twin operation, of which trajectory, due to accompanied atomic relaxation, is not linear and strongly influenced by β phase stability. Plasticity of metastable alloys is extended by the concept of polymorphic deformation modes of which path is sensitive to the composition of the alloy, enabling stabilization of the intermediate transition states. [ABSTRACT FROM AUTHOR]

Recently, considerable effort has been devoted to improving vehicle fuel efficiency and emissions during real road trips. An analysis of vehicle driving energy is typically based on vehicle dynamics, and it has been very effectively used for the analysis of vehicle operation, brake down analysis of the required energy, prediction of vehicle performance, and vehicle control design. In this work, on the basis of the results of driving and powertrain operation analyses performed for diesel sport utility vehicles, a new trip unit of CO2 emission and NOx emission model that reflects real road operating conditions such as the coolant temperature and engine and vehicle efficiency changes is presented. In particular, the developed model does not require detailed powertrain specifications and performance maps, and is constructed to enable simple configuration, easy utilization, and extended application. The model was verified by comparing its results with those of the National Institute of Environmental Research (NIER) driving mode test, which is a domestic vehicle driving mode test, and with the results of an actual road driving analysis. Finally, a model analysis of energy consumption factors for different vehicle speeds on real roads is presented. [ABSTRACT FROM AUTHOR]

The hot ductility of Transformation Induced Plasticity (TRIP) and Twinning Induced Plasticity (TWIP) steels is reviewed, concentrating on the likelihood of cracking occurring on continuous casting during the straightening operation. In this review, the influence of high levels of Al, Si, P, Mn and C on their hot ductility will be discussed as well as the important role B can play in improving their hot ductility. Of these elements, Al has the worst influence on ductility but a high Al addition is often needed in both TWIP and TRIP steels. AlN precipitates are formed often as thin coatings covering the austenite grain surfaces favouring intergranular failure and making them difficult to continuous cast without cracks forming. Furthermore, with TWIP steels the un-recrystallised austenite, which is the state the austenite is when straightening, suffers from excessive grain boundary sliding, so that the ductility often decreases with increasing temperature, resulting in the RA value being below that needed to avoid cracking on straightening. Fortunately, the addition of B can often be used to remedy the deleterious influence of AlN. The influence of precipitation hardeners (Nb, V and Ti based) in strengthening the room temperature yield strength of these TWIP steels and their influence on hot ductility is also discussed. [ABSTRACT FROM AUTHOR]

In this paper, the Seto Inland Sea landscape is analyzed, based on the writings in a travel diary belonging to a landowner during the Meiji period. Tourist guidebooks of that period generally not only described famous scenic spots and historic sites but also human landscapes of the Seto Inland Sea. They also cited legends and waka poems in their descriptions of the landscape. However, intellectuals viewed the Seto Inland Sea as a landscape that would appeal to Westerners as a place of scenic beauty and historic sites. Nevertheless, they considered it more as an archipelago and a human landscape, with port facilities for ships to come and go, and from a natural science perspective they were interested in the components of the land and the living organisms that inhabited it. Although the literati viewed the Seto Inland Sea as an archipelago, the human landscape did not interest them much. Mr. A., the author of the travel diary, did not have a natural scientific perspective, but he did write about the Seto Inland Sea as an archipelago, without focusing much on its scenic spots and historic sites. Further, he also mentioned the human landscapes, such as cities and harbors, and land use in the coastal areas. Since tourist guides also focused on human landscapes, it may be inferred that Mr. A was influenced by the descriptions in the tourist guides of that time. [ABSTRACT FROM AUTHOR]

This study aims to analyze the effect of thermo mechanical coupling damage in the presence of a phase change (austenite/martensite) in 35NCD16 steel. The impact of increasing mechanical traction load, accompanied by a martensitic transformation on the scale of a single grain with boundary has been studied. The prediction transformation of induced plasticity (TRIP) was evaluated by taking into account the following parameters: twenty shear directions of the martensitic plates, two values of the shear deformation of the martensitic plates, energetic and thermodynamics criteria for getting in order the transformation of the martensitic plates, elastoplastic behavior of the two areas in the first case (martensitic plate and grain boundary) and elastic behavior for the grain boundary in the second case. The numerical calculation is carried out using the finite element method (FEM), implemented in the Zebulon calculation code. The developed approach is validated using the available experimental results reported in the literature. The numerical results showed that the estimation of TRIP given by the energetics criteria with the values of the shear deformation (γ0 = 0.16) are closer to the experiment results. [ABSTRACT FROM AUTHOR]

Copyright of ESTOA: Revista de la Facultad de Arquitectura y Urbanismo de la Universidad de Cuenca is the property of ESTOA Revista de la Facultad de Arquitectura y Urbanismo de la Universidad de Cuenca 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.)

Copyright of Progress. Journal of Young Researchers is the property of University of Gdansk / Uniwersytet Gdanskim 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 paper deals with travel vouchers issued by the organizers (travel agencies) during the Covid-19 pandemic and tries to offer a critical perspective on the application of Act No. 185/2020. It deals with the information obligation under the provisions of Section 9 of the lex voucher. The article also deals with vouchers that have been issued by the organizer (travel agency) in violation of legal regulations. The issue addressed is the possibility of rejecting the voucher for reasons specified bylaw for the customer - the contractor and the customer - the beneficiary. The article concludes with a proposal de lege ferenda, which offers a possible solution for customer (consumer) protection in the form of limitation of advances that the organizers receive at the time of negotiating the contract. [ABSTRACT FROM AUTHOR]

This study aims to analyze the effect of thermo mechanical coupling damage in the presence of a phase change (austenite/martensite) in 35NCD16 steel. The impact of increasing mechanical traction load, accompanied by a martensitic transformation on the scale of a single grain with boundary has been studied. The prediction transformation of induced plasticity (TRIP) was evaluated by taking into account the following parameters: twenty shear directions of the martensitic plates, two values of the shear deformation of the martensitic plates, energetic and thermodynamics criteria for getting in order the transformation of the martensitic plates, elastoplastic behavior of the two areas in the first case (martensitic plate and grain boundary) and elastic behavior for the grain boundary in the second case. The numerical calculation is carried out using the finite element method (FEM), implemented in the Zebulon calculation code. The developed approach is validated using the available experimental results reported in the literature. The numerical results showed that the estimation of TRIP given by the energetics criteria with the values of the shear deformation (γ0 = 0.16) are closer to the experiment results.

There is significant evidence from light metals that turbulence in casting leads to bifilm defects; enfolded, doubled-over oxide films which act like cracks in the liquid, and are inherited as cracks by the solid. This population of introduced cracks is now known to significantly influence the tensile failure behaviour of light alloys. There is evidence that analogous defects exist in steels. This paper examines the possibility that bifilms may control the hot ductility of TWIP and TRIP steels, and therefore the problems of straightening during continuous casting. Techniques for overcoming these problems are indicated.

This study examined the effects of perturbation training on the contextual interference and generalization of encountering a novel opposing perturbation. One hundred and sixty-nine community-dwelling healthy older adults (69.6 ± 6.4 years) were randomly assigned to one of the three groups: slip-perturbation training (St, n = 67) group received 24 slips, trip-perturbation training (Tt, n = 67) group received 24 trips, and control (Ctrl: n = 31) group received only non-perturbed walking trials (ClinicalTrials.gov NCT03199729; https://clinicaltrials.gov/ct2/show/NCT03199729). After training, all groups had 30 min of rest and three post-training non-perturbed walking trials, followed by a reslip and a novel trip trial for St, a retrip and a novel slip trial for Tt, and randomized novel slip and trip trials for Ctrl. The margin of stability (MOS), step length, and toe clearance of post-training walking trials were compared among three groups to examine interferences in proactive adjustment. Falls, MOS at the instant of recovery foot touchdown, and hip height of post-training perturbation trials were investigated to detect interferences and generalization in reactive responses. Results indicated that prior adaptation to slip perturbation training, resulting in walking with a greater MOS (more anterior) and a shorter step length (p < 0.01) than that of the Ctrl group, would be associated with a greater likelihood to forward balance loss if encountered with a trip. The trip adaptation training mainly induced a higher toe clearance during walking (p < 0.01) than the Ctrl group, which could lead to reduced effectiveness of the reactive response when encountered with a novel slip. However, there was no difference in the reactive MOS, limb support, and falls between the control group and the slip and trip training groups on their respective opposing novel perturbation post-training (MOS, limb support, and falls for novel slip: Tt = Ctrl; for the novel trip: St = Ctrl, both p > 0.05). Current findings suggested that, although perturbation training results in proactive adjustments that could worsen the reactive response (interference) when exposed to an unexpected opposing perturbation, older adults demonstrated the ability to immediately generalize the training-induced adaptive reactive control to maintain MOS, to preserve limb support control, and to reduce fall risk.

Background: Differences in reactive stepping strategy to recover balance have been investigated as a function of age and sex, but to date have been measured using discrete step or joint specific measures. It is unknown how whole-body strategy or underlying motor control objectives differ between age and sex groups in forward reactive stepping.Research Question: Does whole-body movement and/or motor control strategy differ as a function of age or sex in a forward reactive step to maintain balance?Methods: Forty young and older adults (45 females, 35 males) participated in this study. All participants performed five reactive stepping trials in response to a forward balance perturbation while whole-body kinematics and ground reaction forces were collected. Features of whole-body movement strategy were determined using a principal component analysis model. Average principal component (PC) scores were compared between groups as a measure of whole-body movement strategy and within participant relative standard deviation of PC scores were compared to determine if motor control objectives differed across groups.Results: Significant differences in reactive stepping strategy were observed both as a function of age and sex. Older adults had a greater step length and width, greater anterior trunk and pelvis translation, greater knee flexion angles and anterior translation of the hip joint on the stepping leg compared to young participants. Males had lesser step length and width, as well as greater trunk flexion compared to females. No differences in relative standard deviation of PC scores were observed between age or sex-based groups suggesting that motor control objectives were similar between groups.Significance: This study demonstrates how whole-body movement strategy differs as a function of age and sex, which explains why previously reported discrete outcomes occur. Additionally, it does not seem that motor control strategy objectives differ between age or sex groups in forward reactive stepping. [ABSTRACT FROM AUTHOR]

This work of reflection lays the foundations of the subsumed traveling body in a backpack, which gives rise to a new biocorporality: the backpacking body. We lay the foundation for what the backpack object is, and what is its basic context walking and making the way. Thinking about the backpacking body we observe it in the reality of different paths: firstly, in a material order, from the backpack on the way to Santiago to that given in the path of the great sports exploits; but also in the ideational order, from the backpacking body as aspiration of the journey through the world in the form of a capitalist order, to the backpack as a baggage in the walk of life. [ABSTRACT FROM AUTHOR]