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This paper presents a filled function method to solve economic load dispatch (ELD) of the thermal unit. The proposed method can take care of ELD considering nonlinearity such as valve point loading. The effectiveness of the proposed algorithm has been verified on three different test systems with equality and inequality constraint. Simulation results show that the filled function method is less sensitive to initial values of parameters and is more effective than other previously developed algorithms. In addition, the proposed algorithm is highly promising for the large-scale system. [ABSTRACT FROM AUTHOR]

In this study, infill walls, which are commonly used nowadays, were examined using linear elastic method to investigate the positive and negative effects on steel frame systems under lateral loads. The most common models in structural applications were reviewed, and structural steel and gas concrete were selected for the load resisting frame system and the infill material respectively. The purpose of this study is to show that infill walls have advantages and disadvantages not only under the collapse load, but also under service loading. An equivalent diagonal compression bar model was used for the elastic analysis of infill walls in two-story, two-bay planar frames under lateral loads; and a total number of seven models were analyzed for the combinations of steel frames with, without, and partial infill walls. The strength calculations of the equivalent diagonal compression bar were based on the mechanical and geometric properties of the gas concrete. Effects of symmetrically and asymmetrically placed infill walls on the lateral displacement, rigidity, and natural vibration period of the frame were investigated as well as short column and soft story behaviors. The structures were modeled and analyzed using the SAP2000 structural analysis program. [ABSTRACT FROM AUTHOR]

Nowadays, the mini plates are used for the treatment of mandibula and maxilla fractures. Because of the complex geometry of mandibula and maxilla, the calculation of maximum stress is necessary for determination of the failure probability in the plates which are used for the treatment. For this purpose, the three dimensional (3D) models of mandibula and mini plates have been obtained from real models and then the placement of mini plates to mandibula have been performed. The mini plates' stresses emerged in consequence of different loads have been analyzed using finite element method (FEM). As a result of study, the best results have been obtained from double locking plate in terms of both stresses and reliability. [ABSTRACT FROM AUTHOR]

CoCrMo alloy from metallic implant material use at the production of the prosthesis (especially orthopedic products such as hip and knee prostheses) which used in place of especially hard tissues due to the superior mechanical and corrosion resistance properties. However CoCrMo alloy does not have the required resistance in terms of wear properties. In this study, the material surface was oxidized by plasma at the different process temperatures to increase wear resistance of CoCrMo alloy. After oxidation, depending on the process parameters of surface hardness increased 2-3 times were determined. It was emerged that the wear behaviour of adhesive types of untreated CoCrMo alloy showed. After the plasma diffusion treatments, the composed layers on the surface caused the lower adhesive contact and therefore, wear resistance increased. [ABSTRACT FROM AUTHOR]

Some rock engineering applications require the behaviour of rocks to be known under high strain rate loading. Dynamic properties of rocks are important for mining and civil engineering operations such as cutting, excavating, drilling, blasting and crushing. In this study, split Hopkinson pressure bar (SHPB) method, which is commonly used for dynamic testing of rocks, is used. 7 limestone samples were tested using this method. Analysing the results of dynamic tests, testing method for determining the time-dependent compressive stress and elastic behaviour was explained. Analysis of results showed that dynamic equilibrium condition and constant strain rate during the tests could be achieved with pulse shaping technique. Under same testing conditions, increase in stress with time (loading rate) is more significant for strong samples compared to weak samples. Duration of constant strain rate during testing is larger for strong limestone samples than weak samples. It was found that elasticity modulus is strongly related to strain rate. Samples having high strain rate had lower elasticity modulus. It was found that dynamic compressive strength of rock tested in this study was about 2.5 times the static strength. [ABSTRACT FROM AUTHOR]

Fatigue failure of structures operating under dynamic loadings is widely seen in engineering applications. Electronic equipment, which is widely used in military applications, must be able to survive harsh environments. The endurance of such equipment is defined by the durability of their internal sensitive components. Traditionally, vibration isolation of equipment having commercial of-the-shelf (COTS) electronics is achieved by means of vibration-shock isolators. However, the use of such vibration isolators has some disadvantages. Since most failures occur at mechanical joints such as solder joints and lead wires, ruggedization of sensitive electronic components mounted on PCB's are investigated in this study. Therefore vibration induced fatigue life analysis of an axial leaded aluminum capacitor is performed. Using Step Stress Testing method (SST) component fatigue capabilities, which are used as inputs in further numerical analysis, are obtained. Furthermore, sensitivity analysis for axial leaded capacitor is done in order to focus on the influence of some design parameters on the fatigue life. Finally, the effect of well-known ruggedization techniques in electronic industry like eccobond and silicone reinforcement on the fatigue life of the component is examined. [ABSTRACT FROM AUTHOR]

In this study, abrasion resistance of concrete used for road construction was investigated with respect to the wear resistance of fine agregate. Concrete studied is produced with fine crushed limestone aggregate, fine crushed limestone and basalt commixture and fine crushed basalt aggregate. Abrasion resistance of concrete was measured using Böhme abrasion machine. The data obtained from laboratory study showed that using wear resistant fine aggregate in concrete significantly increases abrasion resistance of concrete. [ABSTRACT FROM AUTHOR]

A sloped face maintained with "rubble-mound" technique, is mostly preferred as far as the coastal structures that are designed and constructed in order to be protected against wave effects are concerned. The main reason is not only the inexpensive and easy handling of rubble-mound operation, but also the satisfactory dissipation of incident waves on this sloped face, decreasing both the dynamic load and the reflected component. The vertical faced coastal structures, on the other side, can be constructed to fulfill many different functions with their constant breadth and suitable draft that can be used both for berthing and handling purposes. However, the vertical faced structures are poor to dissipate reflection or to limit wave run-up, compared to sloped ones, at the same time being exposed to high wave loads especially if they are plain faced. There have been several studies devoted to neutralize these disadvantages and managed to increase the performance of vertical faced structures by means of newly developed front face configurations. On the axis of this very same effort, the main goal of this study is to come up with an optimized structure configuration which will not bring a significant extra cost and will be easy to construct and mount; yet, at the same time which is capable of decreasing wave reflection, wave run-up and wave loads reliably with its high dissipation performance. First, various modifications proposed during past studies for vertical faced coastal structures were gone through. Several theoretical and experimental studies conducted on different variations of chambered breakwaters with a perforated front face have yielded quite satisfactory performance against waves, on the condition that the structure is dimensioned and designed with respect to that specific wave. These breakwaters, called "Jarlan" type after the first one to propose, may give a decreasing performance if incident wave period does not coincide with the resonance properties of their chambers. The partially perforated double chambered structure which is proposed with this study, is able to damp the wave energy with its upper chamber located just above the mean water level, without any strong dependence on the incident wave period, while performing the resonant dissipation to a specific wave frequency with its very shallow lower chamber separated from the upper chamber with a slab-like panel resting at the mean sea level. A plexiglas model of this structure, called as the flow chambered caisson, were manufactured with adjustable chamber breadths and tested under 9 sets of regular and one set of irregular waves, for different frontface perforation ratios and different relative dimensions. All the related performance parameters were derived as dimensionless parameters in order to be valid in any system and both in model and prototype scales. These parameters are reflection and runup coefficients for wave damping; pressure coefficient, force and moment coefficients for dynamic wave loads.… [ABSTRACT FROM AUTHOR]

The fatigue strength evaluation and fatigue strength proof of the welded joints generally is divided into two main concepts, as nominal concept and local concept. These both concepts, depending on the method used and loading conditions allow estimating the fatigue strength of the welded joints. In this study, structural stress concept on the fatigue strength evaluation of the welded joints is handled. [ABSTRACT FROM AUTHOR]

In this study, optimization of space steel frames exposed to seismic loads was carried out by taking into consideration both materially and geometrically nonlinear behaviours via the ANSYS packed program. By taking into account the buckling estimations, the buckling constraints were applied to the optimization technique. For the nonlinear behaviour of the material, the bilinear cinematic hardness model was used and the buckling formulation given in TS 648 was taken in the solutions. For a dynamic solution technique, Newmark method and for the nonlinear solution algorithm, Newton-Raphson methods were used. Solutions were found by preparing subroutine in APDL (Ansys Programming Design Language) coding language of ANSYS packed program. [ABSTRACT FROM AUTHOR]

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