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In several of the cases listed here, the game's developers released the source code expressly to prevent their work from becoming abandonware. Such source code is often released under varying (free and non-free, commercial and non-commercial) software licenses to the games' communities or the public; artwork and data are often released under a different license than the source code, as the copyright situation is different or more complicated. The source code may be pushed by the developers to public repositories (e.g. SourceForge or GitHub), or given to selected game community members, or sold with the game, or become available by other means. The game may be written in an interpreted language such as BASIC or Python, and distributed as raw source code without being compiled; early software was often distributed in text form, as in the book BASIC Computer Games. In some cases when a game's source code is not available by other means, the game's community "reconstructs" source code from compiled binary files through time-demanding reverse engineering techniques.
All these mechanisms of ductile fracture can be observed in front of the crack. However, the stress triaxiality factor alone is not always sufficient to explain changes in the failure mechanism. It has been suggested that other parameters that could be helpful in qualitative and quantitative analysis of fracture mechanisms are the accumulated effective plastic strain and the Lode angle/factor . The Lode angle θ, or one of the Lode parameters ξ, or L are defined as follows:
Distributions of η, L, and εeff_pl in front of the crack. Material S355JR (heat treatment NW, Table 1). (a) The central part of the specimen; (b) the layer located 1.75 mm from the surface; (c) the next to last layer from the specimen axis.
After specimen failure, the fracture surfaces of broken specimens were observed using electron scanning microscope, and finite element analyses were performed using the ABAQUS program. During numerical computations, the finite elements from the ABAQUS standard library were used. In the case of specimens C04 and C1, 4-node, reduced-integration, axisymmetric, solid elements were used (symbol CAX4R). Because large gradients of the computed quantities were not expected, the size of the element next to the notch was 0.138 mm. The other two cases (PN and PR specimens) were modeled using linear 3D hexagonal elements with reduced integration (C3D8R). The sizes of the element in the direction of the greatest stress gradient were 1/20 width of the specimen, i.e., 1.0 mm for the PR specimen and 0.086 mm for the PN specimen. In the case of the S specimen, the C3D8R elements were used, and the size of the element in the shear region was 0.2 mm. The symmetries of the modeled specimens were taken into account to reduce the time of computations. The specimens were loaded by displacements applied at the distance determined by the gauge length (see Figure 3). As a result of numerical computations, the following quantities were recorded over the critical plane: η, L, εeff_pl_cr, and σ22, where σ22 is the crack faces opening stress. In most cases, the microscopic observations revealed the ductile failure via the void mechanism (Figure 5a,b); in some cases, failure due to the slip over slip planes (Figure 5c) took place (in this case, the L parameter must be close to zero), and in some cases, the cleavage failure mechanism (Figure 5d) was observed. The latter mechanism was observed at low temperatures.
Distributions of the effective plastic strain along the crack front. (a) Curves recorded at the final moment of loading after calibration using specimen R1 and the material softening option, material N, temperature +20 °C. (b) Curves recorded at the final moment of loading after calibration using specimen R1 and the material softening option, material N, temperature +20 °C. Strain distributions are presented for all layers through the specimen thickness. (c) Curves recorded at the 25th/30th step of loading after calibration using specimen R1 and the material softening option, material N, temperature +20 °C. (d) Curves recorded at the 20th/30th step of loading after calibration using R1 specimen and the material softening option, material N, temperature +20 °C.
The image of the surface in front of the crack located at the specimen center perpendicular to the crack front, material N, temperature +20 °C. Arrow indicates the crack extension by voids mechanism.
Distributions of the effective plastic strain in front of the crack along the crack front at the final moment of loading after calibration using specimen PR and the material softening option, material HW, temperature +20 °C.
Distributions of the η and Lode functions in front of the crack at the crack centre at the moment when the loading was stopped; specimen PR and the material softening option, material HW, temperature +20 °C.
Hindenburg would serve as the basis of many more icons, and in great detail, author Jesko von Hoegen's monograph leads us through the genesis and construction of each: the genius warlord, the embodiment of the god of war, the repository of trust and confidence, the national hero, the face of victory, and even Otto von Bismarck's successor. When defeat came, its shadows did not touch him. Instead, he and his armies remained "undefeated in the field," and he emerged unscathed as the moderator of the transition from empire to republic, the loyal Eckart (a figure of medieval German sagas), and once again, the savior, but this time as marshal-president, soldier-statesman, substitute kaiser, a transition figure with one foot in the past, the other in the present, around whom all could unite. Of the many symbolic images the old man embodied, this last one, the savior, transcending discord, rallying the disheartened, and illuminating the path of national unity, was the most endearing and the basis of the myth that Hindenburg and Hindenburg alone could rally the nation and hold it together in times of stress. The drama played out with the transition to the Third Reich, symbolized by the reconciliation of the marshal and corporal at the infamous Day of Potsdam.
Hoegen argues that the genesis of the myth stemmed from divisions in Wilhelmine society that existed long before the Reichsgründung: Protestant vs. Catholic, labor vs. capital, urban vs. rural, north vs. south, pre-industrial vs. modern. The Second Reich's founders had papered over but not cemented these cracks, and Wilhelm II proved woefully inadequate at the task of integrating these disparate factions into a unified nation. Aware of their lack of unity at the onset of the war, Germans initially rallied (Burgfrieden, Spirit of 1914), but the longer the war lasted, the greater the likelihood of exacerbating fissures whose rupture could only weaken the effort, leading to calamity. Germany needed a leader who symbolized unity.
The breadth of the Hindenburg myth allowed Germans to view Hindenburg as they wished. He could be something to each: victor, strategist, liberator, symbol of unity, ersatz kaiser, and so on. During the war, the myth largely worked. Hindenburg achieved an almost god-like status, moving from a victorious warlord to the strategic genius at the helm of Germany's war machine--indeed, eclipsing the kaiser, who saw where this sentiment was heading. Though slightly tarnished in the debates over war aims, Hindenburg managed to escape responsibility for the catastrophe that he and Erich Ludendorff had created. Hoegen offers two reasons for this good fortune. First, Hindenburg had become so identified with the nation that to admit he had failed was to concede the nation had as well--a problem that fed the stab-in-the-back legend. The marshal necessarily became its spokesman, and a public that declined to accept reality rushed to blame easy targets. Second, what blame did fall on the military was transferred to Ludendorff. Hoegen expresses his amazement at this development, because military custom placed commanders and their chiefs of staff in the same boat. Hindenburg and Ludendorff owed their appointment to the demise of another commander-chief of staff pairing, Maximilian von Prittwitz and Alfred von Waldersee, who were jointly relieved of duty when the former appeared to lose his nerve on the eve of Tannenberg. While Ludendorff's combative personality and increasing instability made him an easy target, the departure from the norm of viewing commander and chief as inseparable was unique. The defeated nation needed not so much a scapegoat (Ludendorff), claims Hoegen, as it longed for a savior to whom people could rally, and in the turmoil of the revolution, Hindenburg filled the gap. Ludendorff's successor, Wilhelm Groener, presciently and instantly recognized the requirement and made the marshal the "moderator" of the transition from Kaiserreich to republic. This move facilitated the acceptance of the republic while dismissing the megalomania of the High Command as the work of Ludendorff, allowing Hindenburg to escape the catastrophe with his reputation not only intact but also enhanced. He stood poised in 1920 to run for president as ersatz kaiser, but the Kapp Putsch changed matters, and he had to wait five years until Friedrich Ebert died. While at one time or another from 1925 to 1932, virtually all classes and parties, with the exception of the communists and the radical left, had supported Hindenburg, nonetheless, the aura of the marshal dimmed and his inviolability gradually fell apart. Hoegen's chapters on Hindenburg's presidency illustrate well the attacks and insults the old man endured. 2b1af7f3a8