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Gaining access to the cost savings and production efficiencies derived from lowering inventories in the supply chain is as vital for small‐to medium‐sized enterprises (SMEs) as they are for larger manufacturing firms. Lean procurement as a concept has been advanced as a method for achieving this. The purpose of this paper is to discuss a method of addressing some of the critical barriers to implementing lean procurement methodologies in an SME environment through the application of procurement consolidation techniques.

First the relevant theoretical and practitioner literature is reviewed, a theoretical consolidation model is developed, and a worked example is presented.

The barriers face by SMEs trying to implement a lean procurement philosophy are significant. Low volumes, small lot sizes and high frequency purchases incur significant additional distribution costs. The paper argues that the use of a double freight consolidation model (DFCM) is useful to SMEs for maximising the trade‐offs between volume and frequency in an international supply chain.

Whilst this research suggests that SMEs can indeed use the DFCM for lean procurement, the next step is to apply the model in practice.

This paper synthesises consolidation modelling and lean procurement principles. This synthesis is further enhanced by applying a simulated example to the challenging SME environment. The application of the categorisation of both buyers and vendors to the consolidation model is novel.

This study aims to enhance understanding of malnutrition's effect on academic achievement of primary school students.

This is a descriptive, cross-sectional design built on Roy's adaptation model (RAM). This study uses a random cluster sample, consisting of 453 primary school students. Contextual stimuli (mother's educational level, income and child’s breakfast eating) and focal stimuli (wasting, thinness, body mass index and stunting) were examined regarding adaptive responses to student’s academic achievement.

The investigation revealed that Model 1, which took into account factors of age, gender, the frequency of breakfast, income, the number of family members and the education of mothers, explained 12% (R² = 0.12) of the variance in academic achievement. Stuntedness (β = −3.2 and p < 0.01), BMI (β = 0.94 and p < 0.001), family income per month (β = 5.60 and p < 0.001) and mother's education (β = 2.79 and p < 0.001) were the significant predictors in Model 2.

This study provides evidence that malnutrition is associated with ineffective academic achievement. Moreover, variables such as the mother's level of education, family income and the child’s breakfast consumption have a significant impact on academic achievements.

RAM is a useful framework for determining factors affecting people's reactions to difficult circumstances.

This qualitative phenomenological study examined the experiences of patients, their family members, and the nurses in the intensive care unit during critical illness. Five participants from each category participated in two interviews over a period of five months. Content analysis of the interview transcripts revealed five integrating common themes, each reflecting concepts from the Roy Adaptation Model (RAM). The ICU experience among all participants is interdependence. Adaptation in the ICU integrated family as a unit, physical care/comfort, physiological care and psychosocial support, resulting in transformation.

The purpose of this paper is to apply agent-based modeling and simulation concepts in evaluating different approaches to solve ambulance-dispatching decision problems under bounded rationality. The paper investigates the effect of over-responding, i.e. dispatching ambulances even for doubtful high-risk patients, on the performance of equity constrained emergency medical services.

Agent-based modeling and simulation was used to evaluate two different dispatching policies: first, a policy based on maximum reward, and second, a policy based on the Markov decision process formulation. Four equity constraints were used: two from the patients’ side and two from the providers’ side.

The Markov decision process formulation, solved using value iteration method, performed better than the maximum reward method in terms of number of patients served. As the equity constraints conflict with each other, at most three equity constraints could be enforced at a time. The study revealed that it is safe to over-respond if there is uncertainty in the risk level of the patients.

Further research is required to understand the implications of under-responding, where doubtful high-risk patients are denied an ambulance service.

The need for good triage system is apparent as over-responding badly affects the operational budget. The model can be used for evaluating various dispatching policy decisions.

Emergency medical services have to ensure efficient and equitable provision of services, from the perception of both patients and service providers.

The paper applies agent-based modeling to equity constrained emergency medical services and highlights findings that are not reported in the existing literature.

THE study of the flight of birds has provided and will still provide much valuable information for tiie progress of human flight. Many suggestions for the improvements of wings by the use of special wing tips owe their existence to the observation of nature. In spite of such suggestions, free‐flight experimentation—as far as published work goes—is still rather rare and restricted in scope. This reluctance may be due to practical design considerations (handling) as well as to the necessity of making the conventional aileron as efficient as possible; it may also be caused by the impression that experiment in this direction is not worth the effort.

The problem of supplying additional power to a helicopter rotor for take‐off or hovering under overload, hot‐day or altitude conditions is discussed briefly, and the boost system requirements are defined qualitatively. The Mirquardt Aircraft Co. is in process of developing a novel ram‐jet engine to meet these requirements under the sponsorship of the United States Air Force. The progress to date is reviewed, and the eventual application of this engine is discussed.

THE aerodynamic sessions of this year's Annual Meeting were not quite as dramatic as in some preceding years. But how can such sessions remain always at the highest pitch? Aeroplane designers have broken through the sonic barrier and aerodynamicists now understand far better compressibility effects and supersonics. One cannot expect every year a startling announcement of the kind that von Kármán used to make, that the drag coefficient would actually drop in supersonic flight, or that camber contributes nothing to lift at the highest speeds. This intellectual calm is only temporary. Rocket flight at a hundred miles altitude where molecules become individuals will bring tine new problems. So will the design of artifificial satellites. But for the time being, research men and engineers must present papers that dig deep but do not strike out into new territory. Also it is barely possible that there is another reason for the less exciting character of the aerodynamic papers—the word ‘Restricted’. For example, in one session it appeared that the fuel consumption of a jet‐propelled helicopter is still restricted information. To mark things ‘Re‐stricted’ or ‘Confidential’ can become a tiresome habit. However, there was no lack of the striking in other directions. What, for example, could be more intriguing than a session entitled Human Engineering in Aviation? Aeronautics is not all a matter of physics, mathematics, design and innumerable gadgets. It is more than fitting that psychologists, teachers, physicians should play their part and make the life of the pilot an easier one. Of course, the engineers do occasionally develop ‘gadgets’ that help the pilot, as witness the remarkable Sperry Zero Reader (discussed in the Instruments Session), and Air‐Borne Radar (Air Transport Session) that seems to be coming into its own.

This paper aims to comprehensively achieve the requirements of high assembly precision and low cost, a precision-cost model of assembly based on three-dimensional (3D) tolerance is established in this paper.

The assembly precision is related to the tolerance of parts and the deformation of matching surfaces under load. In this paper, the small displacement torsor (SDT) theory is first utilized to analyze the manufacturing tolerances of parts and the assembly deformation deviation of matching surface. In the meanwhile, the extracting method of SDT parameters is proposed and the assembly precision calculation model based on the 3D tolerance is established. Second, an integrated optimization model based on the machining cost, assembly cost (mapping the deviation domain to the SDT domain) and quality loss cost is built. Finally, the practicability of the precision-cost model is verified by optimizing the horizontal machining center.

The assembly deviation has a great influence on cost fluctuation. By setting the optimization objective to maximize the assembly precision, the optimal total cost is CNY 72.77, decreasing by 16.83 per cent from the initial value, which meets economical requirements. Meanwhile, the upper bound of each processing tolerance is close to the maximum value of 0.01 mm, indicating that the load deformation can be offset by appropriately increasing the upper bound of the tolerance, but it is necessary to strictly restrict the manufacturing tolerances of lower parts in a reasonable range.

In this paper, a 3D deviation precision-cost model of assembly is established, which can describe the assembly precision more accurately and achieve a lower cost compared with the assembly precision model based on rigid parts.