Numerical and Experimental Determination of the Feeding Distance of Aluminum Alloys in Gravity Die Casting Using an Optimized Riser Shape

A finite difference thermal model was utilized to analyze the solidification process and to predict the maximum feeding distance in gravity die casting of aluminum alloys with an optimal riser shape. Predictions are verified experimentally for both pure aluminum and A1-12% Si alloy. The experimental maximum feeding distance for castings made from A1-12% Si alloy in gravity diecastings was found to be 10 times the casting thickness, compared to 9.1 times the casting thickness from numerical predictions. For pure aluminum, the experimental maximum feeding distance was 7 times the casting thickness, compared to 6.2 times the casting thickness from numerical analysis.     

An assessment of various process strategies for improving precision in single point incremental forming

Single point incremental forming (SPIF) is a process with the capability to form complex geometries using a tool of very simple geometry, without the need for a matching die. However, large elastic springback resulting from the die-less nature of the process can cause problems if high levels of accuracy are required. The aim of this investigation is to use numerical modelling to investigate different strategies to improve the process precision. A finite-element (FE) model has been used to investigate the effects of adding a backing plate, a supporting kinematic tool and modifying the final stage of the tool path. The results show that the backing plate will minimise the sheet bending near to the initial tool contact location; the additional kinematic tool will reduce springback; and the extension of the tool path across the base of the sheet will eliminate the pillow effect. The cumulative effect of introducing these features to the process shows an improvement in the overall accuracy of the profile and in the thickness distributions of the final product. The results contribute to a better understanding of springback in SPIF.     

丁丁的旅行

“为了部落！”神色庄严的牛头人导师冲着一只棕色的大牛大喊着这句话，而后者显得很有荣誉感的样子，煞有介事的单膝跪地。在他黄褐色的牛角上，一个淡紫色的名字轻轻的漂浮着：“旅行者丁丁”。     

Innovationen in der Holzverabeitung

In a prevous study innovations in the wood working industry were deseribed regarding numerically controlled processing machnies. This article gives a review of the application, of industrial robots and data processing in wood working. The use of computer controlled processes will continue progressively in the future following the example of more, advanced industrial branches. Flexible production methods which make use of all existing machine capacities can reduce production costs considerably.     

Task-specific gesture analysis in real-time using interpolatedviews

Hand and face gestures are modeled using an appearance-based approach in which patterns are represented as a vector of similarity scores to a set of view models defined in space and time. These view models are learned from examples using unsupervised clustering techniques. A supervised teaming paradigm is then used to interpolate view scores into a task-dependent coordinate system appropriate for recognition and control tasks. We apply this analysis to the problem of context-specific gesture interpolation and recognition, and demonstrate real-time systems which perform these tasks     

Prediction of tensile strength of friction stir welded 6061 Al plates

The present paper investigates the prediction of tensile strength after friction stir welding (FSW) using artificial neural network (ANN) in the MATLAB program. The experimental results are used to develop the mathematical model. The combined influence of welding speed, rotation speed, and axial force on the tensile strength of 6061 Al plates is simulated. Results of the tensile test are used to train and test the ANN model. A multi-layer solution is developed using the ANN model to predict tensile strength. Back propagation (BP) method is initially trained using 80% of the experimental data, then, testing is performed with the rest of the data. Results indicate that predicted values are close to the corresponding measured values.     

Measurement of Temperature Increment in Compressive Quasi-Static and Dynamic Tests Using Infrared Thermography

Abstract:  During the plastic deformation of metals, part of the mechanical energy is retained in the material as plastic deformations and the rest is converted to heat. A temperature increment is a measure of the heat energy generated in the tested specimen. This temperature can be detected by measuring the infrared (IR) radiation emitted by the specimen surface. This study describes an attempt to improve the experimental procedure using IR thermography to measure the temperature increment as a function of the plastic strain of the studied materials. Tests were carried out under quasi-static and dynamic load conditions (using a universal testing machine and a Split Hopkinson pressure bar). The method is applied on an Al alloy (Al6082), a Mg alloy (ZC71) and the same Mg alloy reinforced with ceramic particles (SiC, 12 vol%). The emissivity measurement of the studied materials is detailed, as well as the method of synchronising the IR camera with the testing machines. Finally, the influence of test conditions on the measured temperature is analysed.     

New Frontiers in Monoclonal Antibodies for the Targeted Therapy of Acute Myeloid Leukemia and Myelodysplastic Syndromes

Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) represent an unmet clinical need whose prognosis is still dismal. Alterations of immune response play a prominent role in AML/MDS pathogenesis, revealing novel options for immunotherapy. Among immune system regulators, CD47, immune checkpoints, and toll-like receptor 2 (TLR2) are major targets. Magrolimab antagonizes CD47, which is overexpressed by AML and MDS cells, thus inducing macrophage phagocytosis with clinical activity in AML/MDS. Sabatolimab, an inhibitor of T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), which disrupts its binding to galectin-9, has shown promising results in AML/MDS, enhancing the effector functions of lymphocytes and triggering tumor cell death. Several other surface molecules, namely CD33, CD123, CD45, and CD70, can be targeted with monoclonal antibodies (mAbs) that exert different mechanisms of action and include naked and conjugated antibodies, bispecific T-cell engagers, trispecific killer engagers, and fusion proteins linked to toxins. These novel mAbs are currently under investigation for use as monotherapy or in combination with hypomethylating agents, BCL2 inhibitors, and chemotherapy in various clinical trials at different phases of development. Here, we review the main molecular targets and modes of action of novel mAb-based immunotherapies, which can represent the future of AML and higher risk MDS treatment.     

IR, ESCA and Auger analysis of thermally hydrogenated a-Si:H thin films

Hydrogenated amorphous silicon thin films have been prepared by thermal evaporation. IR investigations showed the existence of all expected Si---H. The electron spectroscopy for chemical analysis exhibited the existence of oxygen and carbon atoms on the silicon surface which led to a shift in the Si2p core level. Auger spectroscopy also exhibited a peak shift in the kinetic energy. Both shifts are interpreted on the bases of the environmental change in the amorphous structure.