BACombo—Bandwidth-Aware Decentralized Federated Learning

The emerging concern about data privacy and security has motivated the proposal of federated learning. Federated learning allows computing nodes to only synchronize the locally- trained models instead of their original data in distributed training. Conventional federated learning architecture, inherited from the parameter server design, relies on highly centralized typologies and large nodes-to-server bandwidths. However, in real-world federated learning scenarios, the network capacities between nodes are highly uniformly distributed and smaller than that in data centers. As a result, how to efficiently utilize network capacities between computing nodes is crucial for conventional federated learning. In this paper, we propose Bandwidth Aware Combo (BACombo), a model segment level decentralized federated learning, to tackle this problem. In BACombo, we propose a segmented gossip aggregation mechanism that makes full use of node-to-node bandwidth for speeding up the communication time. Besides, a bandwidth-aware worker selection model further reduces the transmission delay by greedily choosing the bandwidth-sufficient worker. The convergence guarantees are provided for BACombo. The experimental results on various datasets demonstrate that the training time is reduced by up to 18 times that of baselines without accuracy degrade.

A priori prediction of complex liquid–liquid–liquid equilibria in organic systems using a continuum solvation model

Application of Rachford–Rice LLLE (RRL3E) and Henley–Rosen LLLE (HRL3E) algorithms for the prediction of liquid–liquid–liquid equilibria phase behavior of ternary and quaternary systems invoking COnductor like Screening MOdel-Segment Activity Coefficient model.

Behavior of Extended End-Plate Steel Beam to Column Connections

Background: The main objective of this study is to simulate the behaviour of steel beam-to-column connections using the computer package of Finite Element Analysis (FEA) known as “ABAQUS”. Objective: This paper presents the investigations of extended End-Plate connections (EP). A one-model segment is examined under the impact of concentrated load and the exclusive boundary conditions were tested. The analysis of the nonlinear behaviour of the connection is a complicated science and needs to use programs to solve this problem. Experimental works are normally conducted for this type of studies which used more of money, time and effort. Therefore, with the availability of simulation applications, these problems can be addressed. Results and Conclusion: The results of the evaluation were compared with the experimental data from the available literature. In this case, nonlinearity materials were used. A sample study on EP connections was carried out using both material and geometric nonlinearities. The comparison of FEA results with corresponding experimental results confirms the correlation and convergence between them.

Investigation of Redistribution of Pile Foundation Forces Under Successive Loading of Its Elements

Redistribution of pile foundation forces under successive loading of its elements was investigated under laboratory conditions. A segment of pile foundation model was taken for use in the case study. Load tests on the pile foundation model segment, without joining its elements (pile and plate, which turns into grillage) and based on different combinations of static loadings were conducted. This proved that the loading of a plate causes skin friction on some length of the pile side surface as well as providing additional loading and settlement. Test results have shown that application of successive elements enables the foundation to carry loads up to 13% higher than in the case of a standard pile foundation loading with the same settlement rates.

Comparison of results of experimental research with numerical calculations of a model one-sided seal

Paper presents the results of experimental and numerical research of a model segment of a labyrinth seal for a different wear level. The analysis covers the extent of leakage and distribution of static pressure in the seal chambers and the planes upstream and downstream of the segment. The measurement data have been compared with the results of numerical calculations obtained using commercial software. Based on the flow conditions occurring in the area subjected to calculations, the size of the mesh defined by parameter y+has been analyzed and the selection of the turbulence model has been described. The numerical calculations were based on the measurable thermodynamic parameters in the seal segments of steam turbines. The work contains a comparison of the mass flow and distribution of static pressure in the seal chambers obtained during the measurement and calculated numerically in a model segment of the seal of different level of wear.

A Consolidated Model for the Turbine Operation of Centrifugal Pumps

A consolidated model for the turbine operation of centrifugal pumps comprising accurate prediction, optimum selection, and rigorous evaluation has been the primary need and the most challenging tasks for the industry to deal with. This paper introduces a consolidated model that is developed from experimental results of different pump shapes (20–80 rpm) and turbomachine fundamentals directly resulting in the parsimony feature of the model. The model also creates a new basis for dealing with uncertainties. The prediction model segment of the consolidated model requires only the pump shape and size as input parameters for bringing out the complete turbine characteristics. The selection model segment, on the other hand, requires the site head and flow as fixed input parameters and turbine speed as the control parameter to prescribe suitable pumps available in the market. The evaluation model segment compares the absolute turbine characteristics of the suitable pumps and recommends the most suitable pump for the given site. The model also includes an acceptance criterion that relates the deviation of the “pump as turbine” operating parameters with the site parameters, and it is very useful at the evaluation stage. The features of the consolidated model are illustrated with two case studies, which highlight the importance of evaluation in addition to the prediction and basic selection of pumps operating as turbines. In order to increase the accuracy and robustness of the model, the paper recommends an optimization routine stage on the existing model that comprises results of more pump shapes (obtained through field projects or extended laboratory work). The optimization procedure suggested would come a long way to provide a lasting solution for the search of a reliable pump as turbine model.