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The purpose of this paper is to examine the impact of applying two classical controller strategies, including two proportional (P) controllers with two feedback loops and one proportional–integral–derivative (PID) controller with one feedback loop, on the order and inventory performance within a production-inventory control system.

The simulation experiments of the dynamics behaviour of the production-inventory control system are conducted using a model based on control theory techniques. The Laplace transformation of an Order–Up–To (OUT) model is obtained using a state-space approach, and then the state-space representation is used to design and simulate a controlled model. The simulations of each model with two control configurations are tested by subjecting the system to a random retail sales pattern. The performance of inventory level is quantified by using the Integral of Absolute Error (IAE), whereas the bullwhip effect is measured by using the Variance ratio (Var).

The simulation results show that one PID controller with one feedback loop outperforms two P controllers with two feedback loops at reducing the bullwhip effect and regulating the inventory level.

The production-inventory control system is broken down into three components, namely: the forecasting mechanism, controller strategy and production-inventory process. A state-space approach is adopted to design and simulate the different controller strategy.

The purpose of this study is to propose a new dynamic model of a production-inventory control system. The objective of the new model is to maximise the flexibility of the system so that it can be used by decision makers to design inventory systems that adopt various strategies that provide a balance between reducing the bullwhip effect and improving the responsiveness of inventory performance.

The proposed production-inventory control system is modelled and analysed via control theory and simulations. The production-inventory feedback control system is modelled through continuous time differential equations. The simulation experiments design is conducted by using the state-space model of the system. The Automatic Pipeline Inventory and Order-Based Production Control System (APIOBPCS) model is used as a benchmark production-inventory control system.

The results showed that the Two Automatic Pipelines, Inventory and Order-Based Production Control System (2APIOBPCS) model outperforms APIOBPCS in terms of reducing the bullwhip effect. However, the 2APIOBPCS model has a negative impact on Customer Service Level. Therefore, with careful parameter setting, it is possible to design control decisions to be suitably responsive while generating smooth order patterns and obtain the best trade-off of the two objectives.

This research is limited to the dynamics of single-echelon production-inventory control systems with zero desired inventory level.

This present model is an extension and improvement to Towill’s (1982) and John et al.’s (1994) work, since it presents a new dynamic model of a production-inventory control system which utilises an additional flow of information to improve the efficiency of order rate decisions.

This paper aims to optimise the dynamic performance of production–inventory control systems in terms of minimisation variance ratio between the order rate and the consumption, and minimisation the integral of absolute error between the actual and the target level of inventory by incorporating the Pareto optimality into particle swarm optimisation (PSO).

The production–inventory control system is modelled and optimised via control theory and simulations. The dynamics of a production–inventory control system are modelled through continuous time differential equations and Laplace transformations. The simulation design is conducted by using the state–space model of the system. The results of multi-objective particle swarm optimisation (MOPSO) are compared with published results obtained from weighted genetic algorithm (WGA) optimisation.

The results obtained from the MOPSO optimisation process ensure that the performance is systematically better than the WGA in terms of reducing the order variability (bullwhip effect) and improving the inventory responsiveness (customer service level) under the same operational conditions.

This research is limited to optimising the dynamics of a single product, single-retailer single-manufacturer process with zero desired inventory level.

PSO is widely used and popular in many industrial applications. This research shows a unique application of PSO in optimising the dynamic performance of production–inventory control systems.

‘Already there are indications that several big American companies plan ambitious recruitment drives in our universities’

I MUST SAY, I was astonished to read in the editorial in the November issue of Assistant librarian the bald declaration that AL ‘is broke’. I mean, whatever will the printers think?

Reproduces the main texts of hitherto unpublished reminiscences of the style and influence, as a teacher, of Allyn Abbott Young (1876‐1929) by 17 of his distinguished students. They include Bertil Ohlin, Nicholas Kaldor, James Angell, Lauchlin Currie, Colin Clark, Howard Ellis, Frank Fetter, Earl Hamilton, and Melvin Knight (brother of Frank Knight who, with Edward Chamberlin, was perhaps Young’s most famous PhD student). There has recently been a revival of interest in Young’s influence on US monetary thought and in his theory of economic growth based on endogenous increasing returns. These recollections of his students (addressed to Young’s biographer, Charles Blitch) shed light on why Young has, at least until recently, been renowned more for his massive erudition than for his published writings.

The purpose of this chapter is to analyse the interplay between fathers’ perceptions of the workplace and how they enact fatherhood. Data were derived from qualitative in-depth interviews with seven elite, professional fathers employed at multinational manufacturing corporations in Detroit, Michigan. Fathers are highly educated, have a significant income and all but one have wives in the paid labour market. This study shows how the persistence of the ideal worker norm and penalties for using work-family policies (WFP) perpetuate the gendered division of paid and unpaid work. First, fathers who are ideal workers are rewarded; fathers who do not face criticism and obstacles to promotions. Second, management and supervisor’s discretion results in uneven access to WFP, penalizing fathers for asking and preventing most from using them. Third, fathers express desire to be ‘involved’, but their engagement is largely visible fatherhood.

This study extends our theoretical understandings of work, WFP and fatherhood from a distinct departure point – the elite fathers highlighted here have been parenting for at least three years, and live and work in circumstances that seemingly would allow them to disrupt normative expectations of work and family. The United States provides a unique backdrop to examine the navigation of competing work and family demands because reconciliation is largely left to employees and their families. Public and individual company policies are not enough; there must be a corresponding supportive family-friendly culture – supervisor support and penalty-free WFP – to disrupt gendered work and family.

We investigate the association between attributes of the audit committee of a firm and the likelihood of negative events occurring in the firm’s life in Israel. The mandate of the audit committee in Israel is substantially different from its mandate in the US. The responsibilities of the committee in the US are divided between two committees in Israel, one of which deals with reviewing the financial statements and the other one, titled “audit committee,” is in charge of the remaining tasks of the US-type audit committee. This allows us a unique opportunity to focus on the roles of the audit committee other than reviewing the financial statements. Using hand-collected data on firms traded on Tel Aviv Stock Exchange in 2010–2014, we find that the larger the audit committee size, the larger the likelihood of negative events, consistent with the cumbersome workings and potential conflicts of interests characterizing a large committee. The percentage of directors with accounting and financial expertise on the audit committee is associated with a lower likelihood of negative events, in line with the value of such experts in tasks beyond reviewing the financial statements. The fraction of independent directors on the audit committee is not found to be significantly related to the likelihood of negative events. This is consistent with the notion that some independent directors are independent in form but not necessarily in substance, which is surprising in light of the comprehensive regulation regarding audit committee independence imposed by the Israeli regulator.

People with schizophrenia and related psychoses may be more likely to be ‘treatment‐resistant’ when dually diagnosed with intellectual disabilities. This case study highlights many of the difficulties which can occur in their assessment and management. Clozapine is currently the best available intervention for treatment‐resistant schizophrenia, and its use has increased in people with intellectual disabilities. However, it is not always effective, and a wide range of adjunctive strategies have been suggestive and tried. The evidence base for the specific use of these additional strategies in people with intellectual disabilities needs to be increased.