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The Slender Man, an online monster born to the internet in 2009, loves to live in the boundaries, specifically the boundary between the digital and the non-digital worlds. This chapter seeks to explore the full engagement of the community with the myth, analysing it structurally to understand the way, in which the narrative’s construction reflects the relationship of monster to society and society to itself. The sincerity in which the narratives are told, at first appearing intense, is actually a form of play, revealing a boundary blurring between play and non-play as well. While fully engaging in play, the community’s structured narrative is more than this: pulling them into a trapped world in which they play with death in the digital. The triadic structure of the Slender Man narratives reveals an anxiety to the community and their place within broader non-digital worlds.

Based on the error analysis, the authors proposed a new kind of high accuracy boundary element method (BEM) (HABEM), and for the large-scale problems, the fast algorithm, such as adaptive cross approximation (ACA) with generalized minimal residual (GMRES) is introduced to develop the high performance BEM (HPBEM). It is found that for slender beams, the stress analysis using iterative solver GMRES will difficult to converge. For the analysis of slender beams and thin structures, to enhance the efficiency of GMRES solver becomes a key problem in the development of the HPBEM. The purpose of this paper is study on the preconditioning method to solve this convergence problem, and it is started from the 2D BE analysis of slender beams.

The conventional sparse approximate inverse (SAI) based on adjacent nodes is modified to that based on adjacent nodes along the boundary line. In addition, the authors proposed a dual node variable merging (DNVM) preprocessing for slender thin-plate beams. As benchmark problems, the pure bending of thin-plate beam and the local stress analysis (LSA) of real thin-plate cantilever beam are applied to verify the effect of these two preconditioning method.

For the LSA of real thin-plate cantilever beams, as GMRES (m) without preconditioning applied, it is difficult to converge provided the length to height ratio greater than 50. Even with the preconditioner SAI or DNVM, it is also difficult to obtain the converged results. For the slender real beams, the iteration of GMRES (m) with SAI or DNVM stopped at wrong deformation state, and the computation failed. By changing zero initial solution to the analytical displacement solution of conventional beam theory, GMRES (m) with SAI or DNVM will not be stopped at wrong deformation state, but the stress error is still difficult to converge. However, by GMRES (m) combined with both SAI and DNVM preconditioning, the computation efficiency enhanced significantly.

This paper presents two preconditioners: DNVM and a modified SAI based on adjacent nodes along the boundary line of slender thin-plate beam. In the LSA, by using GMRES (m) combined with both DNVM and SAI, the computation efficiency enhanced significantly. It provides a reference for the further development of the 3D HPBEM in the LSA of real beam, plate and shell structures.

The common property of being able to travel faster than sound does not in general confer on aircraft any other similarities of shape or form. Thus supersonic aircraft have no great body of low speed behaviour in common, consequently in order to limit the discussion the following relates to a particular type of supersonic aircraft — namely large transport aircraft of slender delta form.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). In this paper, this important issue was explored using detailed data collected from 75 cases.

This paper was carried out with a comprehensive literature review including the database of the Council on Tall Buildings and Urban Habitat(CTBUH) (CTBUH, 2022), peer-reviewed journals, MSc theses and PhD dissertations, conference proceedings, fact sheets, architectural and structural magazines and other Internet sources. In this study, the case study method was also used to gather and consolidate information about supertall towers to analyze the interrelationships. Cases were 75 supertall buildings in various countries [44 from Asia (37 from China), 16 from the Middle East (6 from Dubai, the United Arab Emirates), 11 from the United States of America and 3 from Russia, 1 from the UK].

The paper's findings highlighted as follows: (1) for buildings in the height range of 300–399 m, the slenderness ratio was usually between 7 and 7.9 and megatall towers were frequently built at a slenderness ratio of 10–15; (2) the median slenderness ratio of buildings in the 400–599 m height ranges was around 8.6; (3) a trend towards supertall slender buildings (=8) was observed in Asia, the Middle East and North America; (4) residential, office and mixed-use towers had a median slenderness ratio of over 7.5; (5) all building forms were utilized in the construction of slender towers (>8); (6) the medium slenderness ratio was around 8 for supertall buildings constructed with outriggered frame and tube systems; (7) especially concrete towers reached values pushing the limits of slenderness (>10) and (8) since the number of some supertall building groups (e.g. steel towers) was not sufficient, establishing a scientific relationship between aspect ratio and related design criteria was not possible.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). This important issue was explored using detailed data collected from 75 cases.

The purpose of this paper is to investigate a partially textured slider of infinite width with orientation ellipse dimples in liquid application.

In this paper, the pressure distribution of lubrication between a partially textured slider and a smooth sliding slider is calculated by the multi-grid method. For the same dimple area, the influence of the ellipse dimple with geometric parameters, and distribution and orientation on the hydrodynamic lubrication is evaluated in terms of the dimensionless average pressure for a given set of operating parameters.

In the present work, the magnitude of the dimensionless average pressure seems proportional to the slender ratio. Consequently, the slender ratio may be chosen as large as possible based on fabrication techniques. The longer axes of ellipse dimples placed parallel to the direction of sliding always show the better hydrodynamic effect. Furthermore, the results show that the ellipse dimples can greatly improve hydrodynamic effect of partially surface textured slider of infinite width by proper design of these texturing parameters.

This paper develops a partial surface texturing infinitely width slider with orientation ellipse dimples for improving hydrodynamic lubrication.

Some historical notes of the early stages in the development of a slender wing supersonic transport aircraft. This article recounts some of the early steps in the development of the concept of a slender wing supersonic transport aircraft during the 1960s, which ultimately led to the design of Concorde. It attempts to indicate how an advanced design problem was met successfully by a completely new approach to aerodynamic design. Since a complete history of the work would fill a large book, the approach is necessarily selective in a way intended to illustrate the development of the main aerodynamic issues.

This paper is aimed at clarifying the behaviour of concrete-filled stainless steel tube (CFSST) slender columns. Based on the review of previous works, it can be found that the pieces of research on the behaviour of CFSST slender columns are very rare and the existing studies, to the author’s knowledge, have not covered this topic in greater depth. The purpose of this paper is to investigate the structural response and strength capacity of eccentric loaded long CFSST columns.

In this paper, a new finite element (FE) model is presented for predicting the nonlinear behaviour of CFSST slender columns under eccentric load. The FE model developed accounts for confinement influences of the concrete in-filled material. In addition, the initial local and overall geometric imperfections were introduced in the numerical model in addition to the inelastic response of stainless steel. The interaction between the stainless section and concrete in-filled was modelled using contact pair algorithm. The FE model was then verified against an experimental work presented in the literature. The ultimate strengths, axial load–lateral displacement and failure mode of CFSST slender columns predicted by the FE model were validated against corresponding experimental results.

The simulation results show that the improvement in the column strengths (compared to hollow section) is less significant when the composite columns have small width-to-thickness ratio. Finally, comparisons were made between the results obtained from FE simulation and those computed from the Eurocode 4 (EC4). It has been found that the EC4 predictions in most analysed cases are conservative for composite columns analysed under a combination of axial load and uniaxial or biaxial bending. However, the conservatism of the code is reduced with a higher slenderness ratio of the composite columns.

The simulation results throughout this research were compared with the corresponding Eurocode predictions.

This paper provides new findings about the structural behaviour of CFSST columns.

The purpose of this paper is to gain from experimental tests an insight into the failure mode of slender steel columns subjected to fire. The tests will also be used to validate a numerical model.

A series of experimental fire tests were conducted on eight full-scale steel columns made of slender I-shaped Class 4 sections. Six columns were made of welded sections (some prismatic and some tapered members), and two columns were made of hot rolled sections. The nominal length of the columns was 2.7 meters with the whole length being heated. The load was applied at ambient temperature after which the temperature was increased under constant load. The load was applied concentrically on some tests and with an eccentricity in other tests. Heating was applied by electrical resistances enclosed in ceramic pads. Numerical simulations were performed with the software SAFIR® using shell elements.

The tests have allowed determining the appropriate method of application of the electrical heating system for obtaining a uniform temperature distribution in the members. Failure of the columns during the tests occurred by combination of local and global buckling. The numerical model reproduced correctly the failure modes as well as the critical temperatures.

The numerical model that has been validated has been used in subsequent parametric analyses performed to derive design equations to be used in practice. This series of test results can be used by the scientific community to validate their own numerical or analytical models for the fire resistance of slender steel columns.

A method has been developed for computing aerodynamic loads on slender missiles with complicated cross‐sections. This method has been applied to the prediction of loads for missiles with folding wings. Comparison of theoretical calculations with supersonic wind‐tunnel measurements indicates that the method should provide satisfactory first estimates of the aerodynamic properties of missiles with folding wings. A series of design charts is presented to allow rapid estimation of lift, folding moment and span loading for a wide variety of folding‐wing configurations.

The purpose of this paper is to present an improved temperature-dependent constitutive model for steel that accounts for local instabilities of slender plates using an effective stress-based method. This model can be easily implemented for use with Bernoulli beam finite elements (FEs) in the fire situation.

The constitutive model is derived by calibration on parametric numerical analysis on isolated plates subject to buckling at different elevated temperatures. The model is implemented in the FE software SAFIR and validation is performed against experimental and shell element analysis results.

A constitutive model based on an equivalent stress method is proposed as an efficient way to consider local buckling in steel members exposed to fire. The proposed stress–strain–temperature relationship is asymmetric and is modified in compression only, by reducing the proportional limit, the yield stress and the strain at yield stress. The reduction of these parameters depends on the plate’s boundary conditions, slenderness and temperature. The validation of the proposed model shows good agreement over a range of profile dimensions, temperatures and steel grades.

The model is still giving conservative results for large compressive load eccentricities. An enhanced model is under development to improve the predictive capability under large eccentricities.

The proposed model, easily implemented into any finite element software, allows using fibre type (Bernoulli) beam FEs for modelling structures made of slender sections. This has major practical implications as beam elements are the workhorse used for simulating the behaviour of structures in fire. This model, thus makes it possible to simulate large structures with slender steel sections at a limited computational cost.

The paper presents a novel steel constitutive model based on an innovative approach to capture local buckling at the material level using an equivalent stress approach. The theoretical development, validation and perspectives for future improvements are presented.