42 resultados para Production management


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Goat fibre production is affected by genetic and environmental influences. Environmental influences which are the subject of this review include bio–geophysical factors (photoperiod, climate–herbage system and soil–plant trace nutrient composition), nutrition factors and management factors. Nutrition and management influences discussed include rate of stocking, supplementary feeding of energy and protein, liveweight change, parturition and management during shearing. While experimental data suggest affects of seasonal photoperiod on the growth of mohair and cashmere are large, these results may have confounded changes in temperature with photoperiod. The nutritional variation within and among years is the most important climatic factor influencing mohair and cashmere production and quality. Mohair quality and growth is affected significantly by rate of stocking and during periods of liveweight loss by supplementary feeding of either energy or protein. Strategic use of supplements, methods for rapid introduction of cereal grains, influence of dietary roughage on intake and the economics of supplementary feeding are discussed. Cashmere production of young, low producing goats does not appear to be affected by energy supplementation, but large responses to energy supplementation have been measured in more productive cashmere goat strains. The designs of these cashmere nutrition experiments are reviewed. Evidence for the hypothesis that energy-deprived cashmere goats divert nutrients preferentially to cashmere growth is reviewed. The influence and potential use of liveweight manipulation in affecting mohair and cashmere production and quality are described. Estimates of the energy requirements for the maintenance of fibre goats and the effect of pregnancy and lactation on mohair and cashmere growth are summarised. The effects and importance of management and hygiene during fibre harvesting (shearing) in producing quality fibre is emphasised. The review concludes that it is important to assess the results of scientific experiments for the total environmental content within which they were conducted. The review supports the view that scientific experiments should use control treatments appropriate to the environment under study as well as having controls relevant for other environments. In mediterranean and annual temperate environments, appropriate controls are liveweight loss and liveweight maintenance treatments. Mohair producers must graze goats at moderate rates of stocking to maximise animal welfare, but in so doing, they will produce heavier goats and coarser mohair. In mediterranean and annual temperate environments, seasonal changes in liveweight are large and influence both quality and production of mohair and cashmere. Mohair and cashmere producers can manipulate liveweight by supplementary feeding energy during dry seasons to minimise liveweight loss, but the economics of such feeding needs to be carefully examined. Strategic benefits can be obtained by enhancing the growth of young does prior to mating and for higher producing cashmere goats.

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Industrial producers face the task of optimizing production process in an attempt to achieve the desired quality such as mechanical properties with the lowest energy consumption. In industrial carbon fiber production, the fibers are processed in bundles containing (batches) several thousand filaments and consequently the energy optimization will be a stochastic process as it involves uncertainty, imprecision or randomness. This paper presents a stochastic optimization model to reduce energy consumption a given range of desired mechanical properties. Several processing condition sets are developed and for each set of conditions, 50 samples of fiber are analyzed for their tensile strength and modulus. The energy consumption during production of the samples is carefully monitored on the processing equipment. Then, five standard distribution functions are examined to determine those which can best describe the distribution of mechanical properties of filaments. To verify the distribution goodness of fit and correlation statistics, the Kolmogorov-Smirnov test is used. In order to estimate the selected distribution (Weibull) parameters, the maximum likelihood, least square and genetic algorithm methods are compared. An array of factors including the sample size, the confidence level, and relative error of estimated parameters are used for evaluating the tensile strength and modulus properties. The energy consumption and N2 gas cost are modeled by Convex Hull method. Finally, in order to optimize the carbon fiber production quality and its energy consumption and total cost, mixed integer linear programming is utilized. The results show that using the stochastic optimization models, we are able to predict the production quality in a given range and minimize the energy consumption of its industrial process.

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This study investigates the attitudes of senior managers in Sri Lankan firms to governance issues using a countrywide cross-sectional survey. Respondents from 64 public firms provide information on manager's attitudes to internal control procedures: (1) producing misleading financial reports, (2) providing faulty investment advice, (3) permitting insider-trading, and (4) providing inaccurate advertising. We establish if these attitudes vary with 5 firm-specific factors: industry group, international exposure of firms, size, whether the firm was listed or not, and whether the firm had a written code of ethics. Employing ordinal logistic regression techniques, the results demonstrate significant variation by respondents within different types of firms. Specifically there was little variation to these issues when respondents were classified by industry, with most variation when classified by international involvement. Respondents from firms with significant international exposures were strongly opposed to most practices, while respondents from firms with written codes of ethics were strongly opposed to the production of misleading reports and insider-trading. Interestingly respondents from listed firms were most opposed to insider-trading, while smaller firms were more opposed to misleading advertising than respondents from larger firms. The results have important implications for the implementation of corporate governance practice.

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Like a number of gull species, the silver gull Larus novaehollandiae has expanded its population in response to human food subsidy. The major anthropogenic food source is food waste at rubbish tips. Other sources of human food waste are also exploited. Many problems result from the activities of these birds, including human health and safety, economic impacts, and effects on the conservation of other species. My study examines aspects of the economic impacts of the silver gull on the human community of the Greater Melbourne Area comprising approximately 4065 km2 (1569 square miles). My data collection method involves identifying sites where problems have been experienced and completing questionnaires during face to face interviews with the managers of those sites. Data collected at this early stage of the study demonstrate that there are significant, quantifiable economic impacts associated with the superabundance of the silver gull in this area. Other impacts, such as reduced amenity and potential health hazards are equally real but more difficult to quantify. Costs include damage to structures and products, damage prevention measures, and loss of production. Information about the costs of these problems will be presented to the relevant landfill management authorities to encourage them to consider alternative means of disposing of putrescible waste, rather than by open landfill disposal, because even current best practice management of open landfill sites (rubbish tips) provides ample opportunity for silver gulls and certain other bird species to exploit this food source. Controlling access by the silver gull to food at rubbish tips would be an important first step in managing the population of this species.

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The demolition activities of buildings produce numerous environmental pressures as a large proportion of demolition waste materials are sent to landfill directly in many projects. Web-based waste exchange systems could provide right solutions for releasing these pressures. Because the approaches adopted in current waste exchange systems are inefficient, these systems cannot generate waste exchange, not achieving their final goal, environmental protection. The Just-in-time (JIT) philosophy has been applied in the manufacture industry for decades and it is proven to be effective to eliminate or minimise inventory during production. This research aims to adopt the JIT philosophy into a demolition project management informapon system so that the system is more efficient in handling waste exchange. The system structure, key components and Just-in-time adoption are proposed and identified. Finally, a proto typed system is demonstrated.

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The recently erected concept of building deconstruction has significantly promoted building components and materials reuse and recycling where building is carefully dismantled into reusable parts. Current research and practices of building deconstruction mainly focus on issues of process before and during the deconstruction such as hazardous material detection, deconstruction design and deconstruction technology. The issues after the deconstruction project are rarely considered. Waste reuse and recycling are enabled through deconstruction yet not practically achieved, and especially the demands of waste building components and materials are hard to appear and match the actual waste production in a building deconstruction project. To deal with this awkward situation, the waste production needs to be conducted in a demand-oriented way. It needs to be thoughtfully planned and scheduled prior to the physical deconstruction as an essential portion of deconstruction project planning and scheduling. Furthermore, the relationship between waste production and structural characteristics of the building creates a serious consideration affecting a deconstruction plan. As a result, a waste production simulation will facilitate waste reuse and recycling in a deconstruction project. It serves as a crucial section of deconstruction planning and design. This research aims to describe the concept of waste production simulation and investigate various management and technical aspects of waste production simulation for building deconstruction projects.

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Building demolition imposes substantial environmental impacts. In particular, large amount of demolition wastes are disposed to landfills. A solution to ease the situation is to maximally reuse and recycle waste building material. Management philosophies such as Just-in-time are applied into demolition project management in order to promote reuse and recycling of demolition wastes. Transportation logistics, widely applied in the manufacturing industry, is ideal to be adopted into demolition projects to optimise waste material production, inventorying, and transportation. In particular, it enables right types and amounts of dismantled building materials to be transferred to right location, and at right time, as required by material demanders. Consequently, waste reuse and recycling can be facilitated. Furthermore, logistics management helps the demolition project team to reduce cost, shorten project duration, and satisfy material demanders. Transportation planning concerns thorough preparation technically and managerially on the demolition site for transportation activities. Information exchange is playing a significant role in delivering and sharing information among project participants, including building owner, demolition project team, potential material demanders, and transporters. This research paper aims to identify the role of transportation logistics in a building demolition project and to analyse inventory control, transportation, and various technical aspects of logistic management for demolition wastes.

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This paper discusses, an application of social marketing relating to pro-environmental awareness and social change. The integration of consumer behaviour theory into social marketing has been highlighted in the literature as requiring greater attention. Social marketing campaigns, like all marketing activities, rely on an understanding of stakeholders' attitudes and motivations in regard to the issue of concern, as well as towards the desired modified behaviour or lack of behaviour. The study highlights the marketing paradigms of benchmarking and social marketing in a not for profit governmental environment. Serrated Tussock has been designated as a weed of national significance and therefore the program has national implications (Thorp 2000). Even though issues associated with introduced species are less publicised than other environmental issues on the world stage, the associated environmental problems are no less severe than those caused by production and consumption activities. Weed control is a widespread problem facing individuals, communities and governments at all levels. A triangulatory approach, involving three distinct phases and incorporating both qualitative and quantitative tools, was used for the research design. The qualitative phase involved focus groups and in depth interviews with landholders, focus groups with professionals in the field and a focus group of key stakeholders. The mail survey resulted in a representative sample of 608 usable responses from the infestation area. The research conducted in this study illustrates how the various stages in the social marketing process were achieved and recommendations consistent with social marketing theory were generated.

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Since the late 1980s, when authors began to deliver typescripts to their publishers on disk, the process of editing and publishing books has been in an almost constant state of change. Not only has digital technology enabled a conflation of book production processes, but books themselves are increasingly available in a wider choice of delivery modes. From traditional hard cover and paperback books, to digital files formatted for printing on desktop printers, to files specifically prepared for delivery via hand-held electronic book-reading devices, to text designed to be read on screen (incorporating hyperlinks that facilitate the reader's ability to navigate around the text and between texts), the consumer now has potential myriad choices for delivery of their chosen content. And the publisher, it seems, has myriad ways to deliver content and to seek and satisfy new markets. As well as opportunities, these changes have caused disruption to the traditional supply chain.

This paper focuses on changes to the role of the editor caused by the digitisation of the publishing industry.

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Sustainable development is a growing area of interest in organisations. Particularly those that have large energy demands for processing, use dwindling raw materials or produce a great deal of waste through production. Knowing those processes that can contribute to making an organisation more sustainable provides a great advantage both in terms of project implementation success and in measurable Triple Bottom Line returns.

In previous research we identified that many of the Information Technology processes used to assist organisations in developing sustainable practices were more clearly suited as Knowledge Management processes (Van Der Meer and Sinnappan, 2008), however less empirical study has been done to categorise them meaningfully.

In this study we have taken these Knowledge Management processes and categorised them according to the sustainable development practice where we identify they can be of service based on Waage et al (2003). Through this we are hoping to develop a framework for organisations to determine what Knowledge Management processes are needed to achieve the particular sustainable development. We may also be able to judge what steps an organisation needs to take to develop further sustainable practices in other areas.

Development of a framework for knowledge management tools in sustainable development would assist industries in determining the best processes for these sustainable projects. This framework also contributes to the body of knowledge on sustainable development and Information Technology.

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Goat fibre production is affected to a similar extent by genetic and environmental influences. Environmental influences include bio-geophysical factors (photoperiod, climate-herbage system and soil-plant trace nutrient composition), country of origin, nutrition factors (live weight, growth patterns) and management factors (farm, herd age and sex structure). Nutrition and management influences discussed include rate of stocking, energy nutrition, live weight change, parturition and management during shearing. The nutritional variation within and among years is the most important climatic factor influencing cashmere production, fibre diameter and fibre curvature (crimp). With productive cashmere goats, large responses to energy supplementation have been measured with optimum nutritional management. The effects and importance of management and hygiene during fibre harvesting (shearing) in producing quality fibre are emphasised.

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Remote and environmentally sensitive sites present unique challenges for participants involved in the design and construction process. Worldwide advances in information technology coupled with improved site accessibility and manageability has enabled the construction industry to undertake such projects with greater ease. Furthermore, research on information technology in construction has begun to focus our attentions on our increased ability to work virtually in distributed teams. These remote sites have a range of development potential as clients have varied interests including; tourism, scientific investigation and resource exploration and processing which impact upon the management of the design process. These sites pose unique challenges to the project teams and in particular for the management of project design. The conceptual design phase is often marked by an iterative and creative process, which tends to be a sociologically oriented world where designers respond to a range of functional, aesthetic, environmental and even spiritual concerns. Strategic decisions made during the briefing and conceptual design stage may impact upon construction logistics and sustainability. Detailed design for construction tends to be a production oriented world. There is a significant body of literature that addresses the application of lean thinking to improving the interface between detailed design and construction production. There is little literature that takes a holistic view of design management for remote sites. The lean design management field of research has much to contribute to the design management of these projects. The review of the literature indicated that much of the lean thinking has been primarily concerned with sequential production. However, lean thinking is based upon principles of flow and value, which is also conducive to the complex process involved in design management for remote sites. A conceptual model is developed that considers both the production and sociological approaches to design management, in response to the peculiar demands of the site and their project teams.

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In this study the nutrition, growth and production of C. destructor was examined. Selected nutritional requirements of juvenile animals were determined under controlled conditions with the aim of developing a pelleted diet for use in hatcheries, nurseries and growout situations. The best developed diet was assessed for its potential as a supplementary feed for animals cultured in earthen environments. The protein requirements were first determined simultaneously with an evaluation of the effect of replacing animal protein (fishmeal) by soybean meal. Juveniles were reared communally for 59 d on isoenergetic diets containing 15-30% protein and graded levels of soybean meal (0-60%, of protein). When soybean meal was included at a level of 40-60%, growth was reduced relative to that achieved with control diets containing 15% and 20% protein, but this was not the case at a 20% soybean meal substitution level. A two-way interaction occurred between dietary protein and soybean meal content. Higher protein feeds enabled higher soybean meal inclusion levels without significantly affecting growth. Protein increases of 5% produced better growth at the 40% and 60% soybean meal substitution levels. This effect was less pronounced in the control and the 20% soybean meal diets. Carcass %protein increased and %lipid decreased as dietary protein increased. A similar effect occurred by increasing the soybean meal level to 60%. No obvious trend in carcass moisture, energy, and ash occurred. A protein requirement of 30% was apparent when fish meal and soybean meal were included in diets at levels of 20% and 24% (dry matter) respectively. Alternative protein sources to soybean meal were subsequently identified. Juveniles were maintained for 12 weeks on isoenergetic diets containing 30% protein and differing in the primary source of protein used, with meat, snail, soybean, yabby, and zooplankton meals comprising the major protein ingredient. No significant difference occurred in mean weight (MW), percentage weight gain (%WG), SGR or survival among diets. Food conversion ratios (FCR) were low, with a minimum value of 0.95 for the snail-based diet. The apparent net protein utilisation (ANPU) varied from 29.6% (zooplankton-based diet) to 41.2% (snail-based diet). Carcass composition varied with diet, with the greatest difference occurring in carapace colour. Animals fed the zooplankton-based diet developed the strongest, most natural pigmentation. A new combination of previously used protein-based ingredients was subsequently tested with reference to two yabby species, Cherax albidus and Cherax destructor, that were grown simultaneously in identical conditions. Juvenile male animals were reared individually for 20 weeks on isoenergetic diets containing 15% or 30% protein with fish meal, soybean meal, yabby meal and wheat products forming the basis of the diets. C albidus grew the fastest and utilised the food the most effectively. Carcass composition was influenced by diet with the 30% protein diet resulting in an increase in carcass protein and ash and a decrease in carcass lipid and energy relative to the low protein diet. Carcass moisture and calcium were not affected by diet. The intermoult period (IP) was highly dependent on the premoult weight (W) but the mean moult increment (WI, as weight) was independent of the PM. The orbital carapace length (OCL) and the abdominal length (ABL) %moult increments generally declined with an increase in PM whereas the propus length (PL) %moult increment generally increased. The IP, WI, %OCL, %ABL, and %PL moult increments varied according to diet and to species. Elevated dietary protein caused a reduction to the IP (for similar sized animals) by 11 d and 7 d and an increase to the WI by 85% and 81% in C. albidus and C destructor respectively. Dietary induced morphological changes also occurred. Animals of a standard OCL (both species) had significantly larger abdomens when fed the higher protein diet. Growth on the best developed diet was compared to the growth obtained on a natural diet of freshwater zooplankton. Juveniles were reared individually for 12 weeks on the two diets. The MW, %WG and SGR were higher for the zooplankton diet. Carcass composition was influenced by diet and the zooplankton fed animals had a higher carcass %protein, %lipid, %ash and %fibre content and were more richly pigmented than animals fed pellets. The IP and the WI were highly dependent on the PM and varied according to diet; feeding with zooplankton reduced the IP by 1.2 days and increased the WI by 13.7% compared to pellets. Nutrient digestibility was determined for the pelleted diets evaluated in the growth trials. Protein digestibility (PD) and dry matter digestibility (DMD), using chromic oxide (Cr2O3) as an exogenous marker, were high for all diets, at around 93% and 83% respectively. Ash digestibility varied considerably from 17% to 73% for the snail and yabby meal diets respectively. Crude fibre digestibility was around 50% and probably indicates cellulase activity. Alternative markers to Cr2O3 were evaluated. Ash was considered to be the most suitable alternative to Cr2O3, providing a reasonable, albeit lower, estimate of nutrient digestibility. Cr2O3 and ash were preferentially excreted whereas fibre was retained in the digestive system for a longer period, consequently, the collection of a particular fraction of the deposited faeces (late or early) substantially affected the digestibility coefficients. In earthen-based environments, animals fed the best developed diet were compared to animals cultured using a forage crop of clover (Trifolium repens). Three supplementary feeding strategies representing varying levels of management intensity were evaluated in a series of trials conducted in ponds and pond microcosms. Growth on pellets consistently exceeded that obtained with the forage crop, with final MW being 67-159% higher than that using clover and appeared to be the result of direct pellet consumption and from a pellet fertiliser effect (on the sediment). Within-pond DMD and PD were high and similar for each treatment (DMD = 51-58%; PD = 89-92%). In the control pond, DMD and PD increased with each successive flood. The faecal egestion rate (PER) decreased with each successive flood in all ponds, and is negatively related to animal weight and to foregut fullness (FF) according to power curves. FF was consistently lowest in the control pond. Mean FF was 48.5%, 62.3%, and 26.7% for the pellet, crop and control ponds respectively. FF increased to the third flood in each pond. The foregut protein content was high in all samples and the mean values were 33.9%, 32.7% and 35.6% for the pellet, crop and control ponds respectively. Foregut ash was highly variable within each pond and is inversely related to the foregut protein content. In the control and pellet ponds the highest foregut ash content occurred during flood 1. The culture system (aquaria or pond) strongly influenced the composition of the foregut content. The foregut of animals fed the manufactured diet (B2) in ponds contained approximately 176% more ash and 5% more protein than the foregut of animals fed in bare-bottom tanks. The FF of the tank fed animals was approximately 45% higher than the FF of pond fed animals after a similar feeding period. Base-line yields for extensive production systems appeared to be around 400kg ha-1. The supplementary addition of T. repens produced yields of approximately 635kg ha-1 (in ponds) to around 1086kg ha-1 (in tanks). The sequential addition of cut-clover to tanks stimulated growth to levels approaching those achieved on pellets. Yabbies stocked into ponds at 15-20 m-2 with a mean weight of 2.67g and fed a 30% protein pelleted diet for 100 d, resulted in a yield of approximately 1117kg ha-1, but only 2% of the population were above a marketable size of 50g. The feed utilisation indices were better for animals reared on pellets in bare-bottom tanks than in earthen environments, indicating some degree of pellet wastage when natural feeds are simultaneously present. High apparent food conversion ratios and low protein efficiency ratios occurred when the forage crop was provided. A considerable quantity of the dry matter and protein content of the forage crop was either inefficiently utilised or directed into other production pathways. Sowing a forage crop into pond microcosms to which a pelleted diet was also provided, did not enhance growth performance. Pelleted feed inputs at a rate of approximately 129g m-2 to 198g m-2 (dry matter) and 38g -2 to 64g m-2 (protein) over 70-100 d resulted in acceptable growth and feed utilisation indices for animals reared in ponds and pond microcosms. Forage crop inputs of approximately 533g m-2 to 680g m-2 (as dry matter) or 84g m-2 to 177g m-2 (as protein) over a 70-100 d period produced reasonable growth rates but poor feed utilisation indices. Low inputs of dry matter (from 113-296g m-2) and protein (from 24-54g m-2) from clover were sufficient to maintain high growth rates in pond microcosms for around 28 d. In ponds, a very low level of 21g m-2 (dry matter) and 4.3g m-2 (protein) was sufficient for around 3 weeks. Forage depletion appeared to occur beyond week 3-4 and was probably a major growth limiting factor. The mean hepatosomatic index (HSI) was 9.44, 7.68, and 6.79 for the pellet, crop, and control ponds respectively. The relationship between hepatopancreas weight and overall animal weight was significantly different between treatments. The hepatopancreas of pellet-fed animals had the highest %lipid and lowest %ash, %protein, %carbohydrate and %moisture content. In terms of absolute quantities, the only major difference in hepatopancreas composition between treatments occurred for lipid and dry matter content. The hepatopancreas of the pellet-fed animals was a cream/cream-yellow colour and was very fragile, whereas in the other ponds it was a more ‘natural’ bright yellow colour and was structurally more robust. C. destructor has a capacious foregut, being approximately 5 times the volume of similar sized Penaeids. The foregut volume (V, ml) of the yabby is related to animal weight (W, g) according to V = 0.048 W0.9543. Animals that were starved for 96 h and then fed diet B2 were almost completely foil after 30 min. The ‘apparent enzymatic response’ of animals fed various natural and artificial diets in tanks was evaluated. Nutrient processing time and the enzymatic response following ingestion appeared to be regulated by the chemical and physical properties of the diet. For the natural feeds, foregut protein was 1.2% higher (for zooplankton) and up to 300% higher (for detritus) than dietary protein, whereas ash was 7.5% higher (zooplankton) and 46-63% lower (detritus) than dietary ash. For animals fed diet B2 after 48 h without food, FF was approximately half that of 96 h starved animals after a similar feeding period but foregut protein and ash contents were similar. Finally, the physiological and morphological attributes elucidated in this study are discussed with reference to the ecology of the yabby. High growth rates, excellent feed utilisation indices and high digestibility coefficients for a wide range of diet-types illustrate nutritional flexibility. A capacious foregut, a large hepatopancreas with a high energy storage capacity, the ability to partition and preferentially excrete the low nutrient value inorganic component of the diet, the capacity to alter body form, nutrient processing time and enzymatic secretions in relation to diet-type, and modified behaviour according to feed availability also demonstrate plasticity/adaptability/flexibility. The combined effect of these important characteristics ensures survival in environments that may be adverse and highly variable in terms of nutrient availability. Collectively the morphological and digestive traits elucidated in this study reflect the generalist-type nature of C destructor and indicate that a polytrophic classification still seems appropriate. Several priority areas for further nutrition research are identified and recommendations are made regarding the best-practices to use in the commercial culture of the yabby. Of paramount importance is the further clarification of the nutritional requirements and feeding preferences of animals in various phases of development.

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The Fiji Government's inability to resolve the differences over land leases is widely seen as a major contributor to the difficulties experienced by the sugar industry. In this paper, however, a different perspective is provided on the industry's problems. In examining the relationship between the profitability of the Fiji Sugar Corporation and sugarcane production, it is found that profitability has had a statistically significant negative effect on sugarcane production, leading to the conclusion that the Fiji Sugar Corporation has been inefficient in the management of the mills, the rail transport system, and sugarcane research.