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\"In August 1942, beleaguered Malta was within weeks of surrender to the Axis, because its 300,000 people could no longer be fed. Churchill made a personal decision that at all costs, the 'island fortress' must be saved. This was not merely a matter of strategy, but of national prestige, when Britain's fortunes and morale had fallen to their lowest ebb. The largest fleet the Royal Navy committed to any operation of the western war was assembled to escort fourteen fast merchantmen across a thousand of miles of sea defended by six hundred German and Italian aircraft, together with packs of U-boats and torpedo craft. The Mediterranean battles that ensued between 11 and 15 August were the most brutal of Britain's war at sea, embracing four aircraft-carriers, two battleships, seven cruisers, scores of destroyers and smaller craft. The losses were appalling: defeat seemed to beckon. This is the saga Max Hastings unfolds in his first full length narrative of the Royal Navy, which he believes was the most successful of Britain's wartime services. As always, he blends the 'big picture' of statesmen and admirals with human stories of German U-boat men, Italian torpedo-plane crews, Hurricane pilots, destroyer and merchant-ship captains, ordinary but extraordinary seamen. Operation Pedestal describes catastrophic ship sinkings, including that of the aircraft-carrier Eagle, together with struggles to rescue survivors and salvage stricken ships. Most moving of all is the story of the tanker Ohio, indispensable to Malta's survival, victim of countless Axis attacks. In the last days of the battle, the ravaged hulk was kept under way only by two destroyers, lashed to her sides. Max Hastings describes this as one of the most extraordinary tales he has ever recounted. Until the very last hours, no participant on either side could tell what would be the outcome of an epic of wartime suspense and courage\"-- Jacket.

The physical processes in tokamak plasma are strongly related to the coupling between the core and the pedestal. The accurate prediction of the kinetic profiles (electron temperature and density) from the pedestal to the core lays the physics basis for fusion performance optimization in future plasma-burning tokamak devices. Based on the optimized width model ( between the pedestal width and the square root of the poloidal pedestal beta ) from empirical observations in type-I edge-localized mode (ELM) H-mode discharges, the REPED model is further used to predict the pedestal structures for type-III ELM H-modes on EAST in this work. By combining the REPED model and the TGYRO transport module, the core-pedestal coupling was initially employed for predicting the kinetic profiles ranging from the axis to the separatrix in H-mode plasma discharges on EAST.

Referring to existing vibration transmissibility function-based approaches, which are frequently applied to diagnose fatigue crack and joint loosening faults in two-dimensional engineering structures such as aluminium plates and steel frames, a novel approach applying nonlinear vibration transmissibility functions is developed to diagnose potential loose pedestals in this paper. Firstly, the two-dimensional structural dynamic model, which simulates effects of loose pedestals as equivalent loads, is obtained through the lumped mass method. Secondly, exciting the dynamic model three times with different extra masses, the transmissibility function-based matrix of one sub-model to be diagnosed is obtained, and then a novel damage index is defined based on the matrix singularity. Lastly, a novel approach with particular procedures is proposed. Through three numerical cases on a two-dimensional dynamic model with multiple degrees of freedom (MDOFs), validity and applicability of the proposed approach are shown. As a result, this paper provides a totally new idea to diagnose loose pedestals, which can ensure structures’ smooth operation.

Bearings often experience ring slip and raceway damage due to fit looseness, which induces abnormal dynamic behavior. In this study, a dynamic model of the shaft-bearing-pedestal system with outer ring slip and damage is developed based on the Hertz contact theory and the lumped parameter method. A three-degree-of-freedom model for bearing ring slip is proposed, and the fractal function is used to characterize the damaged surface morphology of the bearing raceway. The effects of fit looseness on system dynamic response and the damage vibration of the bearing outer ring are investigated through simulation. The typical dynamic characteristics are verified by experiments. The results indicate that an increase in looseness degree leads to a noticeable rise in higher frequencies of the rotating frequency, as well as odd-multiple frequency components appearing in the spectrum. The system undergoes bifurcation, transitioning from periodic motion to chaotic motion. Under the severe looseness condition, sub-harmonic frequencies and continuous spectra further appear in the system. The strong nonlinear impact force between the outer ring and the pedestal is the main reason for the instability and chaotic motion of the system. Due to the outer ring slip caused by bearing looseness, there is a decrease in bearing damage frequency value. This work provides valuable insights for operation, maintenance, and early fault warning related to bearings.

The antenna pedestal in marine satellite communications uses three degrees of freedom, with an added degree to avoid singularity, which can increase joint angular velocity and acceleration. This study models the mechanism in SolidWorks, simulates it in Matlab, uses kinematic equations and the Denavit-Hartenberg method to propose a path that minimizes joint velocity and acceleration during tracking. The novelty of this study as a summary includes first identifying the required degree of freedom to address the redundancy issue and introducing an equation based on that degree of freedom considering the workspace far from singularity to add to the inverse kinematics equations of the mechanism. The second is finding the optimal value of the influential parameter for the mechanism to pass through the farthest range from the singularity when the end-effector passes 90 ∘ above the mechanism, the third is a trade-off between the effects of different variable values from the equation on the angular velocity of the joints and operating in the workspace far from the singularity, and finally, the fourth is finding the optimal value of the parameter from the introduced equation to simultaneously optimize the maximum angular acceleration of the joints and operating in the workspace far from the singularity.

The theoretical investigation of relevant turbulent transport mechanisms in H-mode pedestals is a great scientific and numerical challenge. In this study, we address this challenge by global, nonlinear gyrokinetic simulations of a full pedestal up to the separatrix, supported by a detailed characterisation of gyrokinetic instabilities from just inside the pedestal top to the pedestal centre and foot. We present ASDEX Upgrade pedestal simulations using an upgraded version of the gyrokinetic, Eulerian, delta-f code GENE (genecode.org) that enables stable global simulations at experimental plasma $\\beta$ values. The turbulent transport is found to exhibit a multi-channel, multi-scale character throughout the pedestal with the dominant contribution transitioning from ion-scale trapped electron modes/micro-tearing modes at the pedestal top to electron-scale electron temperature gradient modes in the steep gradient region. Consequently, the turbulent electron heat flux changes from ion to electron scales and the ion heat flux reduces to almost neoclassic values in the pedestal centre. $E\\times B$ shear is found to strongly reduce heat flux levels in all channels (electron, ion, electrostatic, electromagnetic) and the interplay of magnetic shear and pressure gradient is found to locally stabilise ion-scale instabilities.

We report on the results of a survey to document and characterize pedestal craters on Mars equatorward of ∼60°N and 65°S latitude. The identification of 2696 pedestal craters reveals a strong latitude dependence, with the vast majority found poleward of 33°N and 40°S. This latitudinal extent is correlated with many climate indicators consistent with the presence of an ice‐rich substrate and with climate model predictions of where ice is deposited during periods of higher obliquity in the Amazonian. We have measured key physical attributes of pedestal craters, including the farthest radial extents of the pedestals, pedestal heights, and the circularity of the pedestal margins. In conjunction with the geographic distribution, our measurements strongly support a sublimation‐related formation mechanism. This is in contrast to previous hypotheses, which have relied on eolian deflation to produce the elevated plateaus. The identification of marginal pits on the scarps of some pedestal craters, interpreted to be sublimation pits, provide direct evidence for the presence of ice‐rich material underlying the armored surface of pedestal craters. On the basis of our findings, we propose a formation mechanism whereby projectiles impact into a volatile‐rich dust/snow/ice substrate tens to hundreds of meters thick overlying a dominantly fragmental silicate regolith. The area surrounding the resulting crater becomes armored. Pedestals extend to a distance of multiple crater radii, farther than typical ejecta deposits, necessitating an armoring mechanism that is capable of indurating the surface to a distance greater than the reach of the ejecta. Return to low obliquity causes sublimation of the volatile‐rich layer from the intercrater plains, lowering the elevation of the regional terrain. This yields generally circular pedestal craters elevated above the surrounding plains. As a result, the armored surfaces of pedestal craters have preserved a significant record of Amazonian climate history in the form of ice‐rich deposits.

An experiment was conducted to explore the impact of cooling air in a portable bladeless pedestal fan using Peltier modules. Traditional cooling methods face challenges of high energy consumption, motivating the need for innovative solutions. This study hypothesized that integrating Peltier modules into a pedestal fan could significantly enhance cooling efficiency while conserving energy. Investigating the shift from traditional to renewable energy systems for air conditioning (A/C) and ventilation is crucial for achieving sustainability and energy conservation. To meet the comfort standards set by ASHRAE, a study was carried out to design, construct, and assess the cooling efficiency of a bladeless pedestal fan employing Peltier modules. This study also examined how Peltier modules influence the efficiency of a conventional pedestal cooling fan. The experimental study was held in a 4 × 4 m room using two, four, six, and eight Peltier modules at external temperatures ranging from 43°C to 45°C, with indoor starting temperatures of 37°C. Each setup was tested three times and each experimental condition was tested for 60 min, with data recorded at 10‐min intervals. The Peltier effect was utilized to cool water, which in turn cooled the air. The comfort zone was subsequently created using this cooled air. A regression analysis was employed to validate the results, with the cooling performance evaluated using standard error and confidence intervals. The energy savings were estimated by comparing the power consumption of the Peltier module‐based fan to that of conventional pedestal fans and A/C units. The temperature reduction achieved was 4%, 12%, 18%, and 22% with the use of two, four, six, and eight Peltier modules, respectively. The energy analysis indicated significant savings, suggesting that the proposed Peltier‐based bladeless pedestal cooling fan could potentially save over 2000 MW of energy nationwide if it replaced traditional pedestal fans.

The central image of Yakushi Nyorai in the Kondō of Yakushi-ji is a statue closely associated with the imperial household. This study centers on the iconography of the Four Directional Deities and grotesque figures on the pedestal of this statue, while drawing comparative references to related imagery from both China and Japan, in order to reassess the intended meaning behind the iconographic program and, by extension, the original purpose of the statue’s creation. The analysis suggests that the twelve grotesque figures, enclosed within bell-shaped niches on all four sides of the pedestal’s midsection, likely represent the Twelve Divine Generals, who collectively symbolize the Pure Land of Yakushi in conjunction with the Medicine Buddha above. The grotesque figures situated outside the niches on the north and south faces take on the posture of supportive yakṣa and additionally carry the iconographic attributes of beast-demons. Positioned at the lowest register, the Four Directional Deities are interpreted as forming a directional entourage of ascension—either to immortality or to rebirth in the Pure Land. Taken together, these visual elements strongly suggest that the central image of Yakushi Nyorai may have been created as a posthumous votive offering for the soul of Empress Jitō.

Naturally evolved biological structures exhibit the optimal characteristics of light weight, high stiffness, and high strength. Based on the growth mechanism of biological branch systems in nature, an optimization method for internal stiffener plate distribution in box structures is suggested. Under the given load and support conditions, the internal stiffener plates of machine pedestal structures grow, bifurcate, and degenerate towards the direction of maximum overall structural stiffness in accordance with the adaptive growth law. The optimal and distinct distribution of internal stiffener plates with the most effective load path is thus obtained. Based on this, a size optimization for lightweight design is conducted, in which the self-weight of the structures is taken as the design objective, and the natural vibration frequency and static stiffness in the direction that is sensitive to machining accuracy are set as constraints. Finally, an optimized structure is obtained. The effectiveness of the proposed method is verified by using a precision grinder bed as an example. The results of numerical simulation and 3D–printed model experiment indicate that both the dynamic and the static performance of the optimized structure are improved, while the structural weight is reduced by compared with the initial structure. The suggested design method provides a new solution approach for the design optimization of machine pedestal structures.