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Owing to overheating of electronic components during work, more and more attention has been paid to the research of high thermal conductivity polymer composites in recent years. However, traditional way to improve the thermal conductivity of polymer is not ideal. Here, a high-performance polyline-folded graphite paper (PFGP)/epoxy resin (EP) composite was prepared by using polyline-folded graphite paper and liquid epoxy resin as fillers and matrix, respectively. Its out-of-plane thermal conductivity and the improvement efficiency per 1 wt% are as high as 24.19 Wm −1 K −1 and 349%, respectively. Most importantly, this approach is very simple and can be industrialized compared to traditional polymer compounding methods. The thermodynamic finite element analysis in this work simulated the thermal conductivity of PFGP/EP composite at different mass fractions, which can verify the accuracy of the experimental values. These results indicate that the PFGP/EP composites have great prospects in the field of thermal interface materials. • Polyline-Folded graphene paper can create ultra-efficient heat transfer paths. • The prepared composite has an extremely high thermal conductivity. (24.19 Wm−1K−1). • The prepared composite is an excellent candidate for CPU heat dissipation. • The prepared composite can be initially industrialized. [ABSTRACT FROM AUTHOR]

This paper presents analysis, diagnosis and disposal with a typical internal breakdown failure of the resin impregnated paper (RIP) valve side bushing in high voltage direct current (HVDC) converter transformer. Based on the analysis of fault current characteristics at the time of the RIP valve side bushing failure, and field test results of insulation parameters, a method of diagnosing typical breakdown failures of valve side bushings is proposed. Through disassembly inspection of the internal overheating and arcing traces on the failure bushing, the root cause of this typical breakdown failure is found, which is upper axial flashover along the RIP condenser/SF6 interface caused by the abnormal contact of two current-carrying conductive tubes. Temperature distribution inside the bushing with an abnormal contact resistance between the copper conductive tube and aluminum conductive tube under different load current is simulated by using the finite element method. An special device is also developed for repairing defective bushing on-site, and 75 bushings with conductive contact defects have been repaired on the premise of not pushing converter transformers away from the valve hall and even without pulling out defective bushings. [ABSTRACT FROM AUTHOR]

In this article the authors discuss several scientific experimental methodology about orthodontics research. Finite element analysis can simulate headgear treatment using three dimensional initial tooth movement tendencies. A multivariate logistic regression analysis is used to determine the presence of aesthetic impact (AI). Moreover, nasal morphology is considered as an indicator for vertical maxillary skeletal pattern using diagnostic aid cephalogram.

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In the munitions industry, there have been considerable efforts spent to develop low-cost, simply fabricated, easily wearable, and biocompatible bulletproof armors. Recently, long fiber-reinforced composites and shear thickening fluids (STFs) were inceptively utilized to improve bulletproof performance with solid or fabric materials. In this study, Hanji, a cornstarch suspension, Korean traditional long fiber paper, and a well-known STF, respectively, were examined for bulletproof applications to evaluate their own effects on bulletproof performance; tests were carried out in the field and finite element analysis (FEA) was performed to evaluate the behavior of materials regarding with perforated clay areas from in-field tests. It was found that both Hanji and STF influenced the bullet penetration by two factors, namely the momentum of bullet and stress propagation. The cornstarch suspension, rather than Hanji, showed outstanding performance in decreasing the linear velocity of the bullet and minimized the stress propagation to the protecting object. Thus, although STF performed a key role in bulletproof performance, Hanji also proved to be a suitable material as an exterior covering for absorbing the initial impact stress and maintaining the durability and stability of the armor itself. [ABSTRACT FROM AUTHOR]

Researchers often summarize their work in the form of scientific posters. Posters provide a coherent and efficient way to convey core ideas expressed in scientific papers. Generating a good scientific poster, however, is a complex and time-consuming cognitive task, since such posters need to be readable, informative, and visually aesthetic. In this paper, for the first time, we study the challenging problem of learning to generate posters from scientific papers. To this end, a data-driven framework, which utilizes graphical models, is proposed. Specifically, given content to display, the key elements of a good poster, including attributes of each panel and arrangements of graphical elements, are learned and inferred from data. During the inference stage, the maximum a posterior (MAP) estimation framework is employed to incorporate some design principles. In order to bridge the gap between panel attributes and the composition within each panel, we also propose a recursive page splitting algorithm to generate the panel layout for a poster. To learn and validate our model, we collect and release a new benchmark dataset, called NJU-Fudan Paper-Poster dataset, which consists of scientific papers and corresponding posters with exhaustively labelled panels and attributes. Qualitative and quantitative results indicate the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

The finite element model for paper honeycomb was constructed, and the finite element method of out-of-plane compression for the paper honeycomb was studied. Then four kinds of paper honeycomb with different structural parameters were simulated and analyzed using finite element software ABAQUS. Moreover, the results obtained from finite element method were verified based on the existing theoretical research results and experimental results, respectively. The results show that stress–strain curves obtained from finite element method clearly show the four deformation stages of the paper honeycomb under out-of-plane compression, which is basically consistent with the trend of the typical curve. The values of initial peak stress, plateau stress and densification strain are close to the theoretical results. The stress–strain curves and deformation contours coincide with experiments well. The differences of initial peak stress σpk, plateau stress σpl and densification strain εD between theoretical, finite element method and experimental results are less than 15%. Therefore, the finite element method can be used to analyze the stress–strain curves and deformation characteristics of paper honeycomb. In addition, the results also show that the thickness of specimen has little effect on the stress and strain. However, people often prefer to use the thicker paper honeycomb to get better cushioning effect in practical applications, which was explained. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the skiving and cutting stock problem (SCSP) encountered in the paper and plastic film industries, in which a set of nonstandard reels generated from previous cutting processes are used to produce finished rolls through the skiving and cutting process. First, reels are skived together lengthwise to form a reel‐pyramid (a polygon), and then the reel‐pyramid is cut into finished rolls of small widths. Depending on if a reel can be divided lengthwise into subreels to form the reel‐pyramid, the problem can be classified into divisible SCSP (DSCSP) and indivisible SCSP (ISCSP). In this paper, two integer programming (IP) models are proposed for DSCSP and ISCSP, respectively. A sequential value correction procedure combined with the two IP models (SVCTIP) is developed to solve the two SCSPs. The effectiveness of the SVCTIP is demonstrated through extensive computational tests. [ABSTRACT FROM AUTHOR]

IMPACT OF THE PAPER This paper 1 addressed a very specific topic and by itself would not have had much impact in the intervening years. However, most of the paper's content was subsequently included in an extensive report on the Damage Tolerance (DT) properties of aluminium alloys. 2 This report enabled guidelines for flight simulation fatigue crack growth testing to be formulated. 3,4 [ABSTRACT FROM AUTHOR]

Abstract: Objective: This brief review essay was triggered by the discovery of two errors that have been perpetuated in the dental literature for the last quarter century and is intended to alert the research community. Methods: An extensive search of the published literature, using PubMed and Web of Science search engines, electronic journal resources, and several trips to the library for manual retrievals of articles were used to retrieve hundreds of articles reporting on finite element modeling – finite element analysis (FEM/FEA) involving periodontal ligament (PDL) and gutta percha (GP). Results: The literature search revealed that erroneous values for the modulus of elasticity of PDL and GP were introduced in 1980 and in 1983, respectively. The identified errors range between two to three orders of magnitude and have been used in hundreds of FEM/FEA papers. Significance: The finding casts serious doubts regarding the validity of the results published in hundreds of papers and highlights the importance of checking the references cited and citing, or at least confirming, primary sources rather than citing citations. [Copyright &y& Elsevier]

Alternating current (ac) losses in conductor-on-rounded-core (CORC) cables of YBCO high-temperature superconducting (HTS) tapes are a significant challenge in HTS power applications. This study employs two finite element analysis (FEA) models to investigate the contributions from different ac loss components and provide approaches for reducing ac losses in cables. An FEA model based on the T-A formulation treats the cross section of thin superconducting layers as 1D lines and, therefore, only can predict the ac loss generated by the perpendicular magnetic field. In contrast, the model based on H-formulation can be performed on the actual 2D rectangular cross section HTS tapes to provide the total ac losses generated by magnetic fluxes penetrating from both the edges and surfaces of HTS tapes, although this model requires more computing time and memory. The 1D and 2D simulation models were validated by cross comparing the results from both models and by comparing sub-section and full cross section models. Subsequently, two models relate cable design and operational parameters to the surface and edge losses of a two-layer CORC cable by considering the (1) relative contributions of edge and surface losses to the overall ac losses; (2) effect of the current distribution between inner and outer HTS layers on ac losses; (3) impact of the tape alignment on ac losses in each HTS layer; (4) influence of the thickness of HTS layers on ac losses; (5) effect of size and number of inter-tape gaps on ac losses; and (6) contribution frequency on the ac losses. The research results given in this paper are therefore not only valuable to suggest strategies for reducing ac loss in multi-layer cables but also for developing more accurate and effective methods to calculate ac loss in CORC HTS cables. [ABSTRACT FROM AUTHOR]

Buckypapers are thin sheets produced from Carbon NanoTubes (CNTs) that effectively transfer the exceptional mechanical properties of CNTs to bulk materials. To accomplish a sensible tradeoff between effectiveness and efficiency in predicting the mechanical properties of CNT buckypapers, a multi-fidelity analysis appears necessary, combining costly but high-fidelity physical experiment outputs with affordable but low-fidelity Finite Element Analysis (FEA)-based simulation responses. Unlike the existing multi-fidelity analysis reported in the literature, not all of the input variables in the FEA simulation code are observable in the physical experiments; the unobservable ones are the latent variables in our multi-fidelity analysis. This article presents a formulation for multi-fidelity analysis problems involving latent variables and further develops a solution procedure based on nonlinear optimization. In a broad sense, this latent variable-involved multi-fidelity analysis falls under the category of non-isometric matching problems. The performance of the proposed method is compared with both a single-fidelity analysis and the existing multi-fidelity analysis without considering latent variables, and the superiority of the new method is demonstrated, especially when we perform extrapolation. [ABSTRACT FROM AUTHOR]

Origami structures, which were inspired by traditional paper folding arts, have been applied for engineering problems for the last two decades. Origami-based thin-wall tubes have been extensively investigated under axial loadings. However, less has been done with radial stiffness as one of the critical mechanical properties of a tubular structure working under lateral loadings. In this study, the radial stiffness of novel thin-wall tubular structures based on origami patterns have been studied with compression tests and finite element analysis (FEA) simulations. The results show that the radial stiffness of an origami-inspired tube can achieve about 27.1 times that of a circular tube with the same circumcircle diameter (100 mm), height (60 mm), and wall thickness (2 mm). Yoshimura, Kresling, and modified Yoshimura patterns are selected as the basic frames, upon which the influences of different design parameters are tested and discussed. Given that the weight can vary due to different designs, the stiffness-to-weight ratio is also calculated. The origami-inspired tubular structures with superior stiffness performances are obtained and can be extended to crashworthy structures, functional structures, and stiffness enhancement with low structural weight. [ABSTRACT FROM AUTHOR]