MRP-production planning in agile manufacturing

Over the years many researchers have been investigating the area of MRP production planning and still is an area of high interest today. This paper look at production planning where there is unpredictable demands due to the type of product and market a company produces for. Production planning becomes difficult when demand fluctuates unpredictably, and hence a historical sales forecast is used as the initial data for production planning. The sales from previous years, especially in a seasonal market, don't necessarily correlate well to the current and future sales for the next year. A planner working in such environment would have himself frustrating to create a feasible production plan that not only needs to meet customer's demands but also to built up the 'correct' amount of stock for that peak sell season. To overcome some of these problems, This work describes a production planning methodology that can be implemented robustly and quickly. This paper has studied two multi-item lot-sizing problems. We detailed the development of the planning problem mathematically and highlight some solutions to initial problems investigated.

Productivity growth and efficiency change in Malaysian manufacturing : recent evidence from disaggregated data

This paper estimates productivity growth in Malaysian manufacturing over the period 1983-1999. Malmquist productivity Indices (MPIs) have been computed using non parametric Data Envelopment Analysis (DEA) type linear programming, which show productivity growth sourced from efficiency change and growth in technology. Unlike previous studies, this study identifies the Malaysian manufacturing industries at the five digit breakdown of Malaysian Standard Industrial Classification (MSIC) thereby revealing more industry specific efficiency and technical growth patterns. Results indicate that two third of the industries (76 out of total 114 categories) experienced average annual
productivity improvement ranging from 0.1% to 7.8% over the sampled period. Average annual technical progress was recorded by 95 industry categories while technical efficiency improvement was achieved by 53 industries. Overall yearly average indicated relatively low productivity growth from the mid 1990’s onwards caused by either efficiency decline or technical regress. Summary results for industries reveal that some of the high rates of productivity growth have been recorded in glass and glass products (7.3%), Petroleum and coal (7.2%), industrial chemicals (4.9%) contributed from both efficiency improvement and technical progress ranging from 0.8% to 5.4% and from 1.7% to 4.1%, respectively. These results are expected to have some implications for ongoing and future strategic policy reform in Malaysian manufacturing generating a more sustainable growth for specific industry categories.

Recognition of idle resources in time-driven activity-based costing and resource consumption accounting models

Despite its theoretical superiority over traditional volume-based costing models, the Activity-Based Costing (ABC) model has failed to replace traditional volume-based costing models in most organisations. In response to the problems of the model, Time-Driven Activity-Based Costing (TDABC) and Resource Consumption Accounting (RCA) models have been developed as costing models for next generation cost management systems. A key feature that distinguishes TDABC and RCA models from traditional volume-based costing models and the ABC model is the recognition of idle resources in resource pools.

This paper presents a discussion on implications of recognising idle resources in TDABC and RCA models on developments, maintenance and uses of cost management systems. A hypothetical case is presented to illustrate conversions of an ABC-based costing model to ones that are based on the TDABC and RCA models, and the resulting new allocation of resource costs.

Ontogeny of putative GABAergic neurons and their receptors in the nervous system of the crayfish Cherax destructor

Inhibitory neurons exert control the expression of many aspects of behaviour by regulating the effectiveness of excitatory neural function. By comparison with excitatory neural systems, relatively little is known about the development of inhibitory neurons and the influence which these neurons exert on the development of other neural systems. Two issues which relate to the development of inhibitory neurons are of particular interest. First, a paradox arises when inhibitory neurons are considered in terms of modern models of synaptic development which involve activity-dependent mechanisms of synaptic plasticity. Second, there is some evidence that inhibitory neurotransmitters may act in a special trophic manner during the early development of nervous systems. Investigations of these issues would be greatly facilitated in a neural system in which it was possible to experimentally control aspects of the development of individual pre- and postsynaptic cells. The aim of the results presented in this thesis was to characterise the normal development of one such system: the GABAergic inhibitory system of the Australian freshwater crayfish, Cherax destructor. The ontogeny of the inhibitory neurotransmitter GABA across the embryonic period of 30% to 100% development was investigated using immunohistochemical techniques. GABA-like immunoreactive cells and fibres were first detected in the embryonic brain region. The expression of GABA-like immunoreactivity progressed along a rostro-caudal gradient, with GABA-like immunoreactive cells being detected in the most anterior thoracic ganglia at 45% development and in all ganglia by 65% development. GABA-like immunoreactive fibres were evident in peripheral nerves as early as 55% development and ramified extensively throughout the neuropil of the nervous system by 65% development. By contrast, immunoreactivity to the primary excitatory neurotransmitter, glutamate, was not detected until 60-65% development. Glutamate-like immunoreactivity at 60-65% development was evident only in the form of punctate staining in the midline of the ventral nerve cord. Cell body staining was observed only at 90% development and was restricted to only a few cells on the periphery of the ventral nerve cord. Radio-labelled ligand binding methods and autoradiography were used to study the expression of putative GABA receptors in the Cherax embryos from 30% to 100% development. Specific binding was evident in the earliest embryos studies at 30% development. There was an initial increase in binding from 30% to 40% development, followed by a dramatic drop to almost zero binding at 50-55% development. This was followed by a gradual increase in binding levels with age, reaching a plateau at 85% development. Preliminary pharmacological evaluation of binding indicated that at least three GABA receptor types were expressed during embryonic development. Methods for culturing, dissociated neural tissues explanted form Cherax embryos at 85% development were established. The success of cultures was demonstrated by neurite extension, and neuronal networks in which neurons appeared to form connections with other neurons and with explanted muscle cells after two days in culture. Immunohistochemical studies demonstrated that some explanted neurons expressed GABA-like immunoreactivity within two days of explanting. These studies have provided a comprehensive description of the development of GABAergic neurons and their receptors in Cherax destructor embryos. The very early expression of GABA-like immunoreactivity, coupled with the early onset of specific GABA binding, strongly indicates that the GABAergic neurons are functional and able to exert an effect on other cells during much of the period of nervous system development in crayfish embryos. These results support the hypothesis that inhibitory neurons may play an important role as regulators of the overall process of assembly and maturation of the nervous system and provide a substantial basis for future experimental studies in which the specific action of inhibitory neurons on the development of discrete components of the crayfish nervous system may be investigated.

The viability of commercial tomato production in the Autopot system

An investigation of the viability of commercial tomato production using the Autopot growing system in Australia. The Autopot system is a relatively new hydroponic production system technology that is being introduced onto the market in competition with traditional systems. Although commercial tomato production was found to be significantly more water and nutrient efficient in the Autopot system than in a traditional open system, yields were significantly lower. Financial modelling shows that tomato production in this system would not be commercially viable in Australia for a typical tomato growing venture under current conditions.