Dietary and Inhalation Intake of Lead and Estimation of Blood Lead Levels in Adults and Children in Kanpur, India

This research was initiated to study lead levels in various food items in the city of Kanpur, India, to assess the dietary intake of lead and to estimate blood lead (PbB) levels, a biomarker of lead toxicity. For this purpose, sampling of food products, laboratory analysis, and computational exercises were undertaken. Specifically, six food groups (leafy vegetables, nonleafy vegetables, fruits, pulses, cereals, and milk), drinking water, and lead air concentration were considered for estimating lead intake. Results indicated highest lead content in leafy vegetables followed by pulses. Fruits showed low lead content and drinking water lead levels were always within tolerable limits. It was estimated that average daily lead intake through diet was about 114 microg/day for adults and 50 microg/day in children; tolerable limit is 250 microg/day for adults and 90 microg/day for children. The estimated lead intakes were translated into the resultant PbB concentrations for children and adults using a physiologically-based pharmacokinetic (PBPK) model. Monte Carlo simulation of PbB level variations for adults showed that probability of exceeding the tolerable limit of PbB (i.e.,10 microg/dL) was 0.062 for the pre-unleaded and 0.000328 for the post-unleaded gasoline period. The probability of exceeding tolerable limits in PbB level was reduced by a factor of 189 in the post-unleaded scenario. The study also suggested that in spite of the introduction of unleaded gasoline, children continue to be at a high risk (probability of exceeding 10 microg/dL = 0.39) because of a high intake of lead per unit body weight.     

Identifying design criteria for urban system ‘last-mile’ solutions – a multi-stakeholder perspective

Abstract

This study presents a novel approach to design and evaluate ‘last-mile’ solutions – encompassing the social and economic perspectives of key stakeholders. While urban system initiatives have been implemented in practice, theoretical gaps remain at the operational design level. A theoretical framework is developed, based on design criteria identified from a critical synthesis of supply chain and operations management literature, and ‘operationalised’ using an in-depth case study demonstrating implementation of a Consumer Choice Portal-Package Consolidation Centre solution, within a densely populated urban geography. Findings suggest that there is a need to re-define the role of institutional actors beyond that of the traditional governance task, to one of being able to facilitate performance outcomes. Similarly, industrial efficiency dimensions need to be reorientated to include consumer participation, social considerations and multi-stakeholder service outcomes. Finally, implications for operations theory and practising managers in city logistics are highlighted, with suggested directions for future research.     

An integrated model of supply chain performance evaluation and decision-making using structural equation modelling and fuzzy AHP

This paper aims to propose a comprehensive evaluation tool and decision model, which can help the practitioners to gauge their supply chain performance and guide them in decision-making for further improvements. The model provides a salient notion of integrated supply chain performance evaluation approach distilled from the literature. The five important performance evaluation criteria (supply chain planning performance, supply chain partnership performance, production performance, delivery and logistic performance and customer service and satisfaction performance) and corresponding 19 sub-criteria have been identified. An integrated methodology of structural equation modelling (SEM) and fuzzy analytic hierarchy process (FAHP) have been applied to the proposed model to a real case study of Indian textile–apparel–retail supply chain network.     

Stochastic simulation based genetic algorithm for chance constrained data envelopment analysis problems

Genetic algorithm (GA) approach is developed for solving the P-model of chance constrained data envelopment analysis (CCDEA) problems, which include the concept of “Satisficing”. Problems here include cases in which inputs and outputs are stochastic, as well as cases in which only the outputs are stochastic. The basic solution technique for the above has so far been deriving “deterministic equivalents”, which is difficult for all stochastic parameters as there are no compact methods available. In the proposed approach, the stochastic objective function and chance constraints are directly used within the genetic process. The feasibility of chance constraints are checked by stochastic simulation techniques. A case of Indian banking sector has been presented to illustrate the above approach.     

Integrated approach for optimizing quality control in international manufacturing networks

Abstract

This article aims at providing an integrated approach for optimizing quality control in International Manufacturing Networks (IMN) which can be characterized by consisting of numerous plants acting autonomously according to an individual target system. A key challenge is to ensure the overall process quality despite distributed value creation processes and differing target systems in dynamic environments. Hence, the developed approach allows for identifying potentials in the quality control strategy using a value stream-based method to visualize quality characteristics and procedures in the production process chain. Furthermore, the approach contains a framework for identifying possible improvement measures and a simulation-based evaluation concept to evaluate the effects of different measures with respect to individual target systems. The simulation combines elements of a discrete-event simulation in order to depict the value stream with agent-based modelling for realizing different target systems by considering distinctive plant roles. The article concludes with a case study of a globally operating automotive supplier to apply the approach. A forward research agenda is proposed that evaluates the approach in multiple cases, deriving patters across companies or industries.     

Contribution of maximum entropy principle in the field of queueing theory

ABSTRACT

In the literature of information theory, there exist many well known measures of entropy suitable for entropy optimization principles towards applications in different disciplines of science and technology. The object of this article is to develop a new generalized measure of entropy and to establish the relation between entropy and queueing theory. To fulfill our aim, we have made use of maximum entropy principle which provides the most uncertain probability distribution subject to some constraints expressed by mean values.     

THE EVOLUTIONARY LOGIC OF HONORING SUNK COSTS

Although economics claims that sunk costs should not figure in current decision‐making, there is ample evidence to suggest that people squander resources by honoring bygones. We argue that such wastage of resources was tolerated in our evolutionary past by Nature because it served fitness‐enhancing functions. In this study, we propose and model one such function. We demonstrate how the honoring of sunk costs could have arisen as a commitment device that Nature found expedient for scenarios where conflicts over temptations between the emotional and rational centers of the brain might sabotage long‐term investments. By applying this idea to the self‐concept, we argue that this model provides a rationale for cognitive dissonance, a well‐established phenomenon in social psychology. (JEL D01, D03)     

Knowledge management in SMEs and MNCs: matching knowledge mobility mechanisms to supply network configuration profiles

Abstract

While ‘knowledge mobility’ presents significantly different challenges for SMEs and MNCs, it is strongly influenced by two common factors: the type of knowledge to be integrated and the configuration of the operations network. Here, SMEs and MNCs are required to make critical decisions about ‘levels’ of collaboration and knowledge sharing with network partners. A Knowledge Mobility Configuration (KMC) framework was developed, tested and refined using five case studies indicative of a growing shift towards information and knowledge-intensive activities. In terms of contribution, there has been limited empirical research to-date into the determinants of successful knowledge transfers in MNC-SME network contexts. The network configuration element of the KMC framework provides insights on how such networks evolve, and how specific knowledge mobility profiles may evolve over time. This more nuanced approach may be used as a basis for a proactive and differentiated approach to knowledge mobility and integration across SME and MNC networks.