Car Structure Research Articles

Design and validation of fixation points of polymeric components for the automotive industry

ABSTRACT The incorporation of polymeric materials in car structure components plays a key role in the automotive sector, enabling the production of more efficient and ecological vehicles. Among the many options to fix these components, there are clips and snap-fits, which not only facilitate assembly and disassembly, but also contribute to reduce the total mass of the car. This work aims to design and validate these fixation points of polymeric components using the Design Science Research (DSR) methodology. The work resulted from the need for a more rigorous control involving some internal standardized fixation points, namely interior trim parts. Experimental tests were carried out according to the specifications of the automotive brand, including the strength of the fixation points, to enable incorporation as standard components. Using the Finite Element Method (FEM), static simulations were performed in the Abaqus® software, where the conditions of the physical tests were replicated to correlate both tests and validate the numerical approach. Improvement of the fixation points was next undertaken, by making changes in the areas that were identified as critical. The improved fixation points were able to meet the specifications of the company and were proposed as new geometry for standard interior trim parts.

Targeting CD5 chimeric antigen receptor-engineered natural killer cells against T-cell malignancies

BackgroundChimeric antigen receptor engineered T cells (CAR-T) have demonstrated promising clinical efficacy in B-cell malignancies, and the approach has been extended to T-cell malignancies. However, the use of allogeneic T cells in CAR therapy poses a challenge due to the risk of graft-versus-host disease. Recently, natural killer (NK) cells have exhibited “off‑the‑shelf” availability. The nanobody-based CAR structures have attracted much attention for their therapeutic potential owing to the advantages of nanobody, including small size, optimal stability, high affinity and manufacturing feasibility. CD5, a common surface marker of malignant T cells, has three scavenger receptor cysteine-rich domains (D1-D3) in the extracellular region. The present study aims to construct “off‑the‑shelf” CAR-NK cells targeting the membrane-proximal domain of CD5 derived from nanobody against T-cell malignancies.MethodsAnti-CD5-D3 nanobody was screened by phage display technology, followed by constructing fourth-generation CAR plasmids ectopically producing IL-15 to generate CD5 CAR-NK cells derived from peripheral blood. And the second-generation CD5 CAR-T cells based on nanobody were generated, referred to as 5D.b CAR-T and 12 C.b CAR-T. Furthermore, CAR-NK cells without IL-15 (IL-15△ CAR-NK) were generated to assess the impact on cytotoxicity of CAR-NK cells. Cytotoxic activity against CD5+ hematologic malignant cell lines and normal T cells was exerted in vitro and NOD/ShiLtJGpt-Prkdcem26Cd52Il2rgem26Cd22/Gpt mouse model transplanted with Jurkat-Luc cells was used to evaluate the antitumor efficacy of CD5 CAR-NK cells in vivo.ResultsTwo nanobodies (5D and 12 C) competed for binding to the epitope of CD5-D3. 12 C CAR-NK cells were superior to 5D CAR-NK cells in antitumor potential and 12 C.b CAR-T cells exhibited superior cytotoxic activity than 5D CAR-T cells ex vivo. So, 12 C was regarded as the optimal nanobody. 12 C CAR-NK cells and IL-15△ CAR-NK cells exhibited robust cytotoxicity against CD5+ malignant cell lines and controlled disease progression in xenograft mouse model. 12 C CAR-NK cells demonstrated greater antitumor activity compared to that of IL-15△ CAR-NK cells in vitro and in vivo.ConclusionsTaken together, the fourth-generation nanobody-derived anti-CD5 CAR-NK cells may be a promising therapeutic against T-cell malignancies.

Revealing grain refinement and hydrogen trapping mechanism for anti-hydrogen susceptibility of Nb-alloyed 34MnB5 press hardened steel

Hydrogen embrittlement (HE) extant a substantial concern to press-hardened steel (PHS) owing to superior strength. The high strength to light-weight automobile structures necessitates the advancement of superior HE resistance PHS. This study investigated the HE susceptibility of Nb-microalloyed PHS by slow strain rate tensile testing, u-shaped constant bending load test, and thermal desorption spectroscopy. Nb enhances microstructure and HE resistance by introducing retained austenite, refining prior austenite grains (21.14–13.73 μm), forming low-angle grain boundaries, and nano-scale precipitates. Nb-alloyed steel exhibits no-cracking over 300 h under high pre-bending stress and decreases elongation loss up to 48% in hydrogen environment as compared to Nb-free steel. Diffusible H-content in 0.12 wt% Nb-steel reduces to 14.9% of that in Nb-free steel owing to enhanced hydrogen traps, the Fcc/Bcc matrix, and carbide precipitation. The multi-phase microstructure with nano-scale NbC precipitation impeded the localized H-dispersion, enhancing the HE resistance in PHS despite its high strength.

Beyond Conventional Treatments: Exploring CAR-T Cell Therapy for Cancer Stem Cell Eradication.

For decades cancer remained the center of attention in the scientific community as its survival rates are low. Researchers from all around the world wanted to know the core of the problem as to what initiates cancer in a patient and helps with its progression. Many postulations came to light, but Cancer Stem Cells (CSC) was the most appealing and convincing. In this review, we shed light on a potential solution to the problem by reviewing CAR-T cells (Chimeric antigen receptor T cells). These specialized T cells are designed to detect specific antigens on cancer cells. We analyse the steps of their formation from the collection of T cells from the patient's bloodstream and modifying it to exhibit specific CAR structures on their surfaces, to reinjecting them back and evaluating their efficacy. We thoroughly investigate the structure of the CAR design with improvements across different generations. The focus extends to the unique properties of CSCs as in how targeting specific markers on them can enhance the precision of cancer therapy. Despite the successes, the review discusses the existing limitations and toxicities associated with CAR-derived therapies, highlighting the ongoing need for research and refinement. Looking ahead, we explore proposed strategies aimed at optimizing CAR-T cell therapy to mitigate adverse effects for improved cancer treatments.

Axial Crushing and Energy Absorption Integrated Design of Modular Filled Double-Hat Beam Composite Structures.

In order to study the influence of modular filled and composite material forms on the axial crushing and energy absorption properties of structures, modular filled composite structures were constructed, and innovatively applied to the inner side of double-hat beam (DHB) structures in automobiles. The modular filled structures comprise hexagonal, quadrilateral, and triangular sections. By analyzing the collision performance of modular filled DHB structures, significant enhancements were observed in both the sectional characteristics and the specific Mean Crushing Force of modular filled DHBs compared to the conventional double-hat beam structure. These advancements notably improved the plastic deformation characteristics of the structures. Additionally, dynamic weightlessness experiments were conducted to validate the accuracy of the simulation model. Among the proposed schemes, namely QU-5, HE-5, and TR-5, notable improvements in crashworthiness were identified. Specifically, crashworthiness indicators increased by 32.54%, 78.9%, and 116.53%. Compared with other thin-walled structures, modular filled composite DHBs have advantages in axial crushing and energy absorption. By optimizing layout characteristics, the modular filled structures will achieve significant lightweight and energy absorption performance improvements. This work has clear reference value for automotive engineers and scholars to further explore the axial crash safety, platform modularization, and lightweight design of vehicles.

Interleukin-7 expression by CAR-T cells improves CAR-T cell survival and efficacy in chordoma

Chordoma is a rare bone tumor that frequently recurs after surgery, and the prognosis is poor with current treatments. This study aimed to identify potential novel immunotherapeutic targets for chordomas by identifying target proteins in clinical samples as well as tumor microenvironmental factors to enhance efficacy. Fourteen chordoma samples were analyzed by single-cell RNA sequencing, and B7–H3 and IL-7 were identified as potential targets and potentiators, respectively. B7–H3-targeted chimeric antigen receptor T (CAR-T) cells and B7–H3 CAR-T cells expressing IL-7 were synthesized and their anti-tumor activity evaluated in vitro, including in primary chordoma organoid models. The B7–H3 CAR-T/IL-7 therapy showed enhanced cytotoxicity and prolonged duration of action against tumor cells. Additionally, IL-7 modulated favorable subpopulations of cultured CAR-T cells, diminished immune checkpoint expression on T-cell surfaces, and enhanced T-cell functionality. The incorporation of IL-7 molecules into the B7–H3 CAR structure augmented CAR-T-cell function and improved CAR-T-cell efficacy, thus providing a novel dual therapeutic strategy for chordoma treatment.

The technology of Formula 1 racing car

Formula 1 racing is held every year. It dissects every part of an F1 car. Through the observation of F1 cars and watching races, the research data comes from real-time data published by major teams and articles published by well-known Chinese papers. If the power source is fixed, that is, the same pressure air is used as the power, and the simulation software is used to quickly and efficiently complete the design of the car model, to achieve higher speed with less air resistance. Everyone can get a clearer and more accurate picture of the structure of the F1 car. And better study the generation and utilization of aerodynamics. Based on the currently available research, this paper know that F1 cars have been pursuing the ultimate ground flight through constant changes to the body. The Formula 1 car is already the worlds most extreme invention of aerodynamics.

Targeted Therapy of CEA-CAR-NK Cells Against Colorectal Cancer Cells

Objective: Investigate the cytotoxic effect of CAR-NK cells targeting CEA on colorectal cancer cells with positive CEA expression. Methods: The mRNA and protein levels of CEA in different CRC cell lines were detected by qRT-PCR and Western blot analysis. Lentiviral transduction was used to construct CAR-NK cells and empty vector CON-NK cells targeting CEA. Fluorescence microscopy and WB were used to determine whether the cells successfully constructed and expressed CAR structures. The effector NK cells were co-cultured with target cells, and the levels of LDH, IFN-γ, and GM-CSF were detected. The killing rate of effector cells was calculated, and the release of cytokines during the killing of target cells by different effector cells was compared. Results: The expression level of CEA in colorectal cancer patients was significantly higher than that in normal samples and other tumor samples, and the prognosis survival time of patients with high CEA expression was lower than that of CRC patients with low or no CEA expression (P < 0.05). The CEA expression of the HT29 cell line was significantly higher than that of the SW1116 cell line at both the mRNA and protein levels. CEA-CAR-NK92 cells and CON-NK92 cells expressed green fluorescence under a microscope, and WB results showed that CEA-CAR-NK92 cells successfully expressed the CAR structure. Compared with CON-NK92 cells and NK92 cells, CEA-CAR-NK92 cells effectively killed HT29 cells (P < 0.05). CEA-CAR-NK92 cells secreted a large amount of IFN-γ and GM-CSF during the killing of HT29 cells, while the cytokine secretion of CON-NK92 cells and NK92 cells was not significant (P < 0.05). Conclusion: CAR-NK92 cells targeting CEA can effectively kill CEA-positive colorectal cancer cells.

Rapidly-manufactured CD276 CAR-T cells exhibit enhanced persistence and efficacy in pancreatic cancer

BackgroundPancreatic cancer is one of the most lethal malignancies and the lack of treatment options makes it more deadly. Chimeric Antigen Receptor T-cell (CAR-T) immunotherapy has revolutionized cancer treatment and made great breakthroughs in treating hematological malignancies, however its success in treating solid cancers remains limited mainly due to the lack of tumor-specific antigens. On the other hand, the prolonged traditional manufacturing process poses challenges, taking 2 to 6 weeks and impacting patient outcomes. CD276 has recently emerged as a potential therapeutic target for anti-solid cancer therapy. Here, we investigated the efficacy of CD276 CAR-T and rapidly-manufactured CAR-T against pancreatic cancer.MethodsIn the present study, CD276 CAR-T was prepared by CAR structure carrying 376.96 scFv sequence, CD8 hinge and transmembrane domain, 4-1BB and CD3ζ intracellular domains. Additionally, CD276 rapidly-manufactured CAR-T (named CD276 Dash CAR-T) was innovatively developed by shortening the duration of ex vitro culture to reduce CAR-T manufacturing time. We evaluated the anti-tumor efficacy of CD276 CAR-T and further compared the functional assessment of Dash CAR-T and conventional CAR-T in vitro and in vivo by detecting the immunophenotypes, killing ability, expansion capacity and tumor-eradicating effect of CAR-T.ResultsWe found that CD276 was strongly expressed in multiple solid cancer cell lines and that CD276 CAR-T could efficiently kill these solid cancer cells. Moreover, Dash CAR-T was successfully manufactured within 48–72 h and the functional validation was carried out subsequently. In vitro, CD276 Dash CAR-T possessed a less-differentiated phenotype and robust proliferative ability compared to conventional CAR-T. In vivo xenograft mouse model, CD276 Dash CAR-T showed enhanced anti-pancreatic cancer efficacy and T cell expansion. Besides, except for the high-dose group, the body weight of mice was maintained stable, and the state of mice was normal.ConclusionsIn this study, we proved CD276 CAR-T exhibited powerful activity against pancreatic cancer cells in vitro and in vivo. More importantly, we demonstrated the manufacturing feasibility, acceptable safety and superior anti-tumor efficacy of CD276 Dash CAR-T generated with reduced time. The results of the above studies indicated that CD276 Dash CAR-T immunotherapy might be a novel and promising strategy for pancreatic cancer treatment.

Identifying patterns in loading a gondola car body with reinforcing belts in the structure of side walls

The object of this study is the processes of occurrence, perception, and redistribution of loads in the body of a gondola car with reinforcing belts in the structure of side walls. In order to improve the strength of side walls of the gondola car body, it is proposed to strengthen them with additional belts. At the same time, it is reinforced with diagonal belts in three sections of the body on the side of the consoles, and in the middle section, 1/3 of the height from the lower strapping, with a horizontal belt. To determine the parameters for the execution of profiles in the reinforcing belts, the calculation of the gondola car body as a rod system was carried out. Based on the resulting values of bending moments, the moment of resistance of the cross-section of the profiles of the reinforcing belts was determined. The calculation of the strength of the body of the gondola car under the main modes of its loads in operation (I and III calculation modes) was carried out. It was found that the resulting stresses were 10.3 % lower than those occurring in a typical design of a gondola car body. The movement of the gondola car in the empty and loaded states was evaluated. A feature of the reported research results is that the improvement of the strength of the side walls of the gondola car body is achieved by increasing the rigidity of its frame. The field of practical use of the results is the engineering industry, in particular, railroad transport. The conditions for the practical application of results are the symmetrical distribution of reinforcing belts along the length of the gondola car body. This study results may contribute to improving the durability of gondola car bodies in operation, and accordingly to reducing costs for unscheduled repairs. Also, the findings could prove useful for designing modern structures of railroad cars

IMMU-06. CAR DESIGN SHAPES THE BRAIN TUMOR IMMUNE MICROENVIRONMENT: IMPACT ON ACTIVITY AND PERSISTENCE OF ANTI-GLIOMA ADOPTIVE T CELL IMMUNOTHERAPY

Abstract BACKGROUND B7-H3 CAR T-cells effectively eradicate brain tumors in xenograft models and have proven safe in clinical trials, yet no objective responses were observed in patients. The limited efficacy is partly attributed to the immunosuppressive tumor microenvironment (TME), a characteristic not fully recapitulated in investigations using xenograft models. In this study, we set to optimize B7-H3 CAR structure and examine the effects of CAR design on the brain TME using an immunocompetent glioma model. METHODS We generated a panel of fully murine B7-H3 CARs with variations in transmembrane, co-stimulatory, and activation domains. This enabled us to comprehensively investigate their effector functions within the intact immune system. High-dimensional flow cytometry and single-cell RNA sequencing were then used to investigate changes in the brain TME following CAR T-cell therapy. RESULTS While five out of six B7-H3 CARs with single co-stimulatory domains exhibited potent functionality in vitro, optimizing co-stimulation and signaling failed to enhance their anti-glioma efficacy in vivo. To further enhance therapeutic effectiveness and persistence, we incorporated 4-1BB and CD28 co-stimulation through transgenic expression of 4-1BBL on CD28-based CAR T-cells. Although this design significantly improved anti-glioma efficacy in vitro, it conferred no additional benefits in vivo. Analysis of the TME revealed that CAR T-cell therapy influenced the immune composition of the brain TME. Successful anti-tumor responses were dictated by the recruitment, activation, and spatial localization of unique inflammatory ‘immune hubs’ containing specific subsets of macrophages and endogenous T-cells. Interestingly, depletion of brain macrophages using CSF1R inhibitor markedly inhibited CAR T-cell anti-tumor activity. CONCLUSION Our study highlights the critical role of CAR structural design and its modulation of the TME in mediating the efficacy of CAR T-cell therapy in brain tumors. Yet, more specific targeting and/or reprogramming of the TME is warranted for the successful design of effective adoptive immunotherapies for high-grade glioma.

Use of IL-3RB to mediate antitumor effect of CAR-T cells through the JAK-STAT signaling pathway.

2541 Background: The application of CAR-T in solid tumors has not yet demonstrated significant clinical benefits. The continuous proliferation and decreased terminal differentiation of CAR-T cells in vivo are considered potential strategies that could alter this predicament. Cytokines, as the 3rd signal for T-cell activation, play a crucial role in the lifecycle and fate of T cells. In this study, we innovatively incorporated the IL-3 receptor β chain (IL-3RB) into the CAR structure to enhance signal transduction, potentially activating the anti-tumor function of CAR-T and maintaining the persistent proliferative activity. Methods: Transcriptional profiling analysis performed on HER2 or VEGFR1 CAR-T cells, with a specific focus on the gp140 cytokine family (IL-3/IL-5/CSF-2) and the receptor expression, validated by ELISA and Western blot. By cloning CAR genes containing different structural domains of the IL-3RB into the lentiviral vector pWPXLd, CAR expression, activation, depletion, proliferation, cytotoxicity, pSTAT3 and pSTAT5, and cytokine release of CAR-T cells were assessed using flow cytometry (FCM), Western blot (WB), RTCA, CCK-8, and ELISA. Subcutaneous/abdominal injections of SKOV3 cells or SKOV3-Luc cells into NSG mice, followed treated by CAR-T cells. Tumor burden was regularly monitored, and FCM and Q-PCR were utilized to assess the quantity and phenotype of CAR-T cells in vivo. Results: RNA-sequence, ELISA and WB revealed that upon activation of CAR-T cells, the expression of genes such as IL-3/IL-5/CSF-2 rapidly increased. However, their receptors were hardly expressed. IL-3RB modification did not affect the phenotype of resting CAR-T cells. But, co-cultured with target cells, IL-3RB significantly enhanced the anti-tumor effects of CAR-T cells. This was manifested by more rapid activation, promotion of persistent proliferation, delayed exhaustion phenotype, secretion of higher levels of cytokines (IL-2, IFN-γ, TNF-α) and efficient cytotoxicity. IL-3RB-expressing CAR-T cells exhibited activation of the JAK kinase and STAT3, STAT5 transcription factor signaling pathways in vitro. We established solid tumor models of subcutaneous (SKOV3) and intraperitoneal metastasis, where HER2/VEGFR1 CAR-T cells partially inhibited tumor cell growth in vivo. In contrast, IL-3RB-enhanced CAR-T cells completely eradicated tumor cells, and even achieving a state of complete remission. FCM and Q-PCR also confirmed that IL-3RB significantly improved the proliferation and survival of CAR-T cells in vivo. Conclusions: IL-3RB is scarcely expressed in T cells and not regulated by T cell activation. IL-3RB-modified CAR-T cells exhibit superior persistence and significant anti-tumor advantages in a solid tumor through the JAK-STAT signaling pathway. Our innovative CAR structure design has the potential to demonstrate promising anti-tumor effects in clinical translational applications.

Activating innate immune responses repolarizes hPSC-derived CAR macrophages to improve anti-tumor activity

Generation of chimeric antigen receptor macrophages (CAR-Ms) from human pluripotent stem cells (hPSCs) offers new prospects for cancer immunotherapy but is currently challenged by low differentiation efficiency and limited function. Here, we develop a highly efficient monolayer-based system that can produce around 6,000 macrophages from a single hPSC within 3weeks. Based on CAR structure screening, we generate hPSC-CAR-Ms with stable CAR expression and potent tumoricidal activity invitro. To overcome the loss of tumoricidal activity of hPSC-CAR-Ms invivo, we use interferon-γ and monophosphoryl lipid A to activate an innate immune response that repolarizes the hPSC-CAR-Ms to tumoricidal macrophages. Moreover, through combined activation of Tcells by hPSC-CAR-Ms, we demonstrate that activating a collaborative innate-adaptive immune response can further enhance the anti-tumor effect of hPSC-CAR-Ms invivo. Collectively, our study provides feasible methodologies that significantly improve the production and function of hPSC-CAR-Ms to support their translation into clinical applications.

МАТЕМАТИЧНЕ МОДЕЛЮВАННЯ ПРОСТОРОВИХ КОЛИВАНЬ РУХОМОГО СКЛАДУ ЗАЛІЗНИЦЬ

The development of railway transport is accompanied by the introduction of innovative equipment and modern information technologies. The creation of railway rolling stock and rail machinery requires an assessment of their strength and dynamic qualities even at the stage of design and experimental production, therefore, the development of specialized software for evaluating the main parameters of the rolling stock structures being created is an urgent scientific and applied problem for railway transport and transport engineering. Theoretical studies of spatial fluctuations of certain types of railway rolling stock were performed and recommendations were obtained for the formation of parameters of the structures of freight cars and special rolling stock. When conducting theoretical research, the author's DYNRAIL-PRO software complex was used, which was verified and the reliability of the calculation results was proven.

Does the new energy vehicles subsidy policy decrease the carbon emissions of the urban transport industry? Evidence from Chinese cities in Yangtze River Delta

New energy vehicles (NEV) have become an important driving force for carbon reduction in the transportation industry. This paper adopts the extended environmental pressure assessment (STIRPAT) model and the time-varying difference in differences (DID) model to evaluate the effectiveness of the NEV subsidy policy to achieve sustainable governance. The results show that the NEV subsidy policy can significantly decrease the carbon emission of the transport industry. The mechanism analysis results indicate that the NEV subsidy policy can decrease carbon emissions by promoting a green transformation of the consumer car purchasing structure. Further analysis found that a “fraudulent subsidy” can significantly weaken the policy effect of subsidies. The results of heterogeneity analysis indicate that the subsidy policies introduced by different levels of government have different effects. The subsidy policy of the central government has a more significant effect, and repeated subsidies from central and local governments will weaken the policy's effectiveness. These findings provide valuable insights for policymakers in developing countries to optimize subsidies for new energy vehicles in reducing carbon emissions in the transportation industry.

Comparative performance of scFv-based anti-BCMA CAR formats for improved T cell therapy in multiple myeloma

In multiple myeloma (MM), B cell maturation antigen (BCMA)-directed CAR T cells have emerged as a novel therapy with potential for long-term disease control. Anti-BCMA CAR T cells with a CD8-based transmembrane (TM) and CD137 (41BB) as intracellular costimulatory domain are in routine clinical use. As the CAR construct architecture can differentially impact performance and efficacy, the optimal construction of a BCMA-targeting CAR remains to be elucidated. Here, we hypothesized that varying the constituents of the CAR structure known to impact performance could shed light on how to improve established anti-BCMA CAR constructs. CD8TM.41BBIC-based anti-BCMA CAR vectors with either a long linker or a short linker between the light and heavy scFv chain, CD28TM.41BBIC-based and CD28TM.CD28IC-based anti-BCMA CAR vector systems were used in primary human T cells. MM cell lines were used as target cells. The short linker anti-BCMA CAR demonstrated higher cytokine production, whereas in vitro cytotoxicity, T cell differentiation upon activation and proliferation were superior for the CD28TM.CD28IC-based CAR. While CD28TM.CD28IC-based CAR T cells killed MM cells faster, the persistence of 41BBIC-based constructs was superior in vivo. While CD28 and 41BB costimulation come with different in vitro and in vivo advantages, this did not translate into a superior outcome for either tested model. In conclusion, this study showcases the need to study the influence of different CAR architectures based on an identical scFv individually. It indicates that current scFv-based anti-BCMA CAR with clinical utility may already be at their functional optimum regarding the known structural variations of the scFv linker.

The Influence of Profitability and Capital Structure on Company Value with Dividend Policy as a Moderating Variable in Consumer Companies which is listed on the Indonesian Stock Exchange for the 2018-2021 Period

This research aims to examine and analyze the company value of consumer companies listed on the Indonesian Stock Exchange. The variables tested include Profitability, Capital Structure, Company Value with Dividend Policy as a Moderating variable. This research involves consumer companies listed on the Indonesia Stock Exchange during the 2018-2021 period. Sample selection was carried out using the purposive sampling method. The data used is external data, obtained from the site www.idx.co.id. The data analysis process was carried out using PLS Algorithm calculations using SmartPLS and then hypothesis testing was carried out. Results. Research shows that Profitability has a positive relationship towards Company Value, Capital Structure has no effect on Company Value, Dividend Policy is unable to mediate the influence of Profitability and Car Structure on Company Value.

Testing and identification method for the interfacial heat transfer coefficient between CFRTP and tools under fast hot-stamping conditions

Carbon fiber reinforced thermoplastic composites (CFRTP) are increasingly applied in automobile structures. Hot-stamping is a fast forming process for complex components of CFRTP. During hot-stamping process, the variations of temperature field occur in entire forming process, which ultimately have an impact on the forming quality and dimensional precision of the part. The interfacial heat transfer behaviour between CFRTP and tools directly determines the temperature distribution in the part. However, the existing heat transfer testing and identification methods are designed for sheet metal, which may not be applicable for CFRTP due to the differences in material properties and forming processes. Therefore, in this work, a new test device was developed to reproduce the interfacial heat transfer behaviour of CFRTP under various hot-stamping conditions, and an inverse identification method of the interfacial heat transfer coefficient (IHTC) between CFRTP and tools was proposed. The influences of contact conditions on the IHTC were investigated, including the interfacial contact pressure, interfacial clearance, heating temperature of tools and sheets. The results showed that the IHTC demonstrated a positive correlation with the contact pressure. However, the IHTC would significantly decrease with the existence of a clearance at the interface. Within the entire heat transfer process, it was also found that an increase in tool temperature resulted in a decrease in the IHTC, while initial sheet temperature didn't exert a significant influence. Furthermore, the reliability of proposed testing and identification methods had been verified by the hot-stamping for U-shaped CFRTP parts. The temperature error between the simulation and experiment was less than 5 %.

ANALYSIS OF IMPACT OF STATIC AND DYNAMIC LOADS ON THE STRUCTURAL ELEMENTS OF THE ROLLING STOCK

In the operation of railway rolling stock, special attention is paid to the dynamic characteristics of the behavior of structural elements of wagons and locomotives. Under these conditions, the magnitude and nature of the change in the forces arising from the interaction of the track and rolling stock, as well as the interaction of all elements of the car structure with each other, are the main parameters determining traffic safety and wear of the elements of the rolling stock structure. This article examines the influence of static and dynamic loads on the running gear of the car, in particular the load on the side frame of the cargo bed (18-100). To determine the stress-strain state of the side frame of the cargo trolley, experimental and theoretical (computational) studies were carried out, which made it possible to determine the main stress zones in the side frame of the trolley trolley, both with permissible deviations in the parameters of the components of the trolley in operation, and with the presence of defects in the running gear affecting traffic safety. Based on the results obtained, an assessment of the negative combinations of malfunctions of the trolley elements affecting the further failure of the parts and components of the chassis of the car is given. The factors for the development of constructive recommendations aimed at improving the structural elements of the side frames of cargo trucks are determined.

Design and simulation of structural durability of passenger car front in collision

In this paper, design and calculate a damping system with HYPERMESH software. Research using LS-DYNA software to analyze finite element model and structural strength of passenger car front and violate the safe space on impact. Simulation results with a speed of 50 km/h according to ECE R66 standards show a reduction of 27%. Meet the requirements on the condition of the car head structure. The safe space is not violated according to ECE R66 standards in a head-on collision. Additionally, the numerical analysis techniques employed in this study could be used for future research on collisions between maritime structures including fishing boats and aquaculture engineering. Keywords: ECE R66 standard, HYPERMESH software, LS-SYNA software, collision, passenger car, damping system.