Group ranking of two-stage production units in network data envelopment analysis

Data envelopment analysis (DEA) is a useful mathematical tool for evaluating the performance of production units and ranking their relative efficiency. In many real-world applications, production units belong to several separate groups and also consist of several sub-units. In this paper, we introduce a new method of evaluating group efficiency of two-stage production systems. To this end, some new DEA models are introduced for evaluating and ranking groups of production systems based on the average and weakest group performance criteria. Some numerical examples, including an empirical application in the banking industry, are also provided for illustration.

Organizational culture and Employee engagement: A Review of selected studies

The study attempts to examine the effect of organizational culture on employee engagement and performance and its evaluation has been identified by certain selected researcher’s research. The main aim of research article is to identify and determine strong relationship between organizational culture and employee engagement as well as performance. Employee engagement and effectiveness could prove to be an excellent parameter to assess the health of the organization as such with regards to satisfaction, innovation, commitment, retention and productivity. Literature review is adopted as methodology to review the culture of an organization upon employee engagement and performance. The owners and top management of an organization generally tends to have a large impact on establishing a culture. Organizational culture plays a vital role in engaging the employees and enhancing their performance. Organizational culture must be united all members and employees of the organization as this will encourage uniformity among members of the organization and this enhance commitment, group efficiency and overall performance of employees. In this study it was tried to look at the effect of organizational culture on employee’s engagement and performance with evidence of selected related literatures.

Large-scale model tests of a single pile and two-pile groups for an offshore platform in sand

Estimating pile group efficiency for open-ended steel piles in small group arrangements is a challenging task for designers. This paper reports on the large-scale experimental campaign performed for the BorWin gamma offshore converter platform, which involved single piles and two-pile group systems on a scale of 1:10. The experimental works included installation, dynamic end-of-driving tests, dynamic restrike tests, and static load tests of a single pile and a pair of two-pile groups in densely compacted, artificially prepared homogeneous sand. The CPT profiles and the blow counts confirmed that the foundation systems are comparable to each other. The experimental results of the single pile system were compared with conventional design methods. Such comparison indicated that CPT-based methods and load-transfer methods are applicable at the considered model scale. The bearing capacity prediction obtained via the CAPWAP method is conservative with respect to the static capacity. A consistent setup effect can be detected by analyzing the complete dynamic loading session. The pile group efficiency for the given foundation system was found to be less than 1.0 at both very small and very large soil strains, while it equaled 1.0 at failure.

Numerical investigation on pile group efficiency embedded in soft clay

Purpose This paper aims to investigate the pile group efficiency based on the load-settlement response in soft clay conditions, considering several pile configurations using a variable number of piles and pile spacing. The overall objective of the present paper is to provide further insight into the mechanical response of the pile group and aim at helping the engineers in taking a logical path in an iterative design process for pile group efficiency. Design/methodology/approach To investigate the pile group efficiency, three-dimensional (3D) numerical simulations were performed using the finite-difference code FLAC3D. Findings The obtained numerical results are validated by comparing them to those of similar subgrade structure and in comparable geological conditions provided within the literature. The results indicated that although the bearing capacity of the pile group increases with increasing number of piles, the efficiency of the pile group is very important for a small number of piles. However, increasing of pile spacing has a positive effect on pile group efficiency depending on piles number and settlement level. The pertinence of the 3D numerical results of efficiency coefficient is judged by comparison with those obtained from the most popular formulas available in the literature. Originality/value A predicted model is also proposed which is validated with the obtained numerical results to a better goodness of fit.

A Review on Interaction Effect of Pile under Vertical Compression

The present theories and methods for design of the vertically loaded pile foundations generally provides the overall values of bearing capacity and settlement characteristics for the pile groups. In every design criteria for vertically loaded pile system, there are some factors affecting on major scale such as bearing capacity, Settlement, skin friction etc. This review paper shows that the consequences of vertical load on pile foundation done by various researchers and from their results help in predicting the load–settlement behavior of vertically loaded pile and pile groups. It is observed, when the group efficiency is close to unity, the variation between expected and observed behavior of piles proves to be a positive approach towards the ultimate load. Hence, various researchers have tested and published their laboratory and theoretical values on load-settlement characteristics under the influence of vertical load on pile foundation. This paper illustrates about comparison of various test results and their research gap on consequences of vertically loaded pile foundation.

Application of centralised DEA in an automobile parts retail network in Taiwan

PurposeThe purpose of this study is to address three managerial issues in a retail network under a centralised regime, including resource allocation, expansion and downsizing. In particular, this study investigates how to optimise resource allocation across retailers and how to decide the optimal size of a retail network for an empirical case, where 27 retailers belong to an automobile parts supplier in Taiwan.Design/methodology/approachThe centralised data envelopment analysis (DEA) approach is used to optimise resource allocation among retailers and to seek the possibility of either an expansion and/or downsizing for a retail network.FindingsThe case company knows the best way to (re)allocate its available resources and (re)arrange the outcome goals for its own retailers. The 27 retailers are assigned specific targets for input and output adjustments to become Pareto or technically efficient units. Besides, an experiment is designed to measure how changing the number of retailers affects the group efficiency of the retail network. To keep the current aggregated output level of the retail network, the centralised supplier needs at least 24 retailers. However, the retail network with 37 retailers can achieve maximal group efficiency.Originality/valueCentralised resource allocation is an inherent feature of most supplier-retailer relationships, where the supplier is usually a central planner with the power to allocate available resources among its own retailers. To the best of our knowledge, this is the first study to assess retail performance under a centralised regime.