969 resultados para yield management


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FiSAT program was used to estimate population parameters of Upenaeus sulphureus from length frequency data. Loc and K were found to be 22.7 em and 0.98 year1 respectively. The Wetherall plot provided an estimate of L= and Z/K were 21.585 em and 4.759 respectively. The annual rate of natural and fishing mortality were estimated as 1.91 and 3.86 respectively. The exploitation rate was 0.668. The selection pattern Lc was 10.824 em. Recruitment pattern suggest of two uneven seasonal pulses in March-April and August-October. Peaks appeared in August-October. Maximum yield could be achieved simultaneously increasing length at first capture to 10.0 em. The length weight relationship was found to be W =0.03065 Lz.8328. Highest yield and price could be achieved by decreasing the fishing mortality to 0.9 coefficient rate.

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FiSAT program was used to estimate population parameters of Rastrelliger kanagurta from length frequency data. Loc and K were found to be 27.4 em and 0.90 year1 respectively. The Wetherall plot provided an estimate of Loc and Z/K were 26.7 cm and 4.683 respectively. The annual rate of natural and fishing mortality were estimated as 1.71 and 3.21 respectively. The exploitation rate was 0.652. The selection pattern L50 was 18.09 cm. Recruitment pattern suggests two seasonal pulses one in March-May and another in September-October. Peak recruitment appeared in March-May. Maximum yield could be achieved by decreasing length at first capture to 13.0 em. The relationship between total length and body weight was found to be W = 0.01583 L8952. Yield and stock prediction analysis suggested that highest yield and price could be achieved by decreasing the fishing mortality to 2.0 coefficient rate.

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A comparative study of benthic fauna between Rajdhala beel and Padmai beel of Netrakona District under different management system was carried out from July 1999 to January 20OO. An average number of 1113 and 1175 organisms/m2 were obtained from Rajdhala heel and Padmai beel respectively. A total of 22 taxa belonging to 8 diverse groups, Oligochaetes, Chironomids, Molluscs, Ceratopogonids, Diptera (other than Chironomids and Ceratopogonids), Ephemeroptera, Leeches and Crustaceans were recorded. Oligochaetes were dominated and constituted 46% and 49% ofthe total benthic population in Rajdhala heel and Padmai beel respectively. The next dominant group was the Chironomids, which constituted 31% and 30% of the total benthic population in Rajdhala beel and Padmai beel respectively. The highest number 1279 and 1437 individuals/m2 of benthic fauna was recorded in December from Rajdhla beel and Padmai bee! in respectively. The lowest number of benthic fauna 869 and 914 individuals/m2 were found during September and July from Rajdhala beel and Padmai beel respectively. Monthly variation of benthic fauna among two beels were found statistically significant (p<0.05). The numerical distributions of benthic fauna was found to be varied with depth ranges. However, the depth wise variation of total benthic fauna between two heels was not found statistically significant. Fish yield of Rajdhala beel (488 kg/ha/yr) was appreciably higher than the Padmai beel (250 kg/ha/yr).

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There have been considerable changes in fish species composition in Lakes victoria, Kyoga and Nabugabo since the Nile perch were introduced. Populations of most of the native species have declined and many species may have become extinct. The original decline in the fish stocks was due to overfishing but the recent and more drastic decline has been attributed to predation by the Nile perch. Nile perch feeds on invertebrates changing to a piscivorous diet with size. Haplochromine cichlids, which were the most abundant fish in Lakes Victoria just before the Nile perch populations started increasing rapidly have been depleted. As more suitable types of prey were depleted in the new habi tats, Nile perch switched to other prey types to the extent of feeding even on its own young. There are, fears that the Nile perch will overshoot its food supply, resulting in a reduction of its own population and subsequently a collapse in the fishery (FAD 1985).

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Estimates of potential yield for Kainji Lake, and the methods of analysis by earlier workers are discussed. Also summarized is the state of the fishery after impoundment, between 1969 and 1971, based on experimental gillnet catches. Recent sampling of the young of the year along the littoral margin indicates that most of the commercially important species have spawned successful1y in the lake. An intense fishing mortality of juvenile fish, owing to the use of small mesh nets by local fishermen, presents a possible threat to the future establishment of the fish in the lake. The results of gill-net selection studies based on HOLT'S (1957) method are given. The data have been extracted from experimental gill-net catches with graded fleets of nets between 1969 and 1971. Recommendations based on the above studies have been made to ensure a successful establishment of the fish species in the lake and an increase in catch-per~unit effort in subsequent years.

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Fisheries science is concerned with ultimate yield prediction and control. The subject deals with the study of natural history of stocks and the dynamics of fish populations. The multiple species fisheries of Lake Victoria are undergoing rapid development. Already, some of the highly valued fish species have been reduced to very low population levels. The most abundant but less relished Haplochromis spp. remain underutilized. The real problem in management is to win acceptance for regulations that foster increasing productivity in the industry, without slavish adherence to status quo.

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ap Gwilym, Owain, McManus, Ian, and Thomas, Stephen, 'The role of payout ratio in the relationship between stock returns and dividend yield', Journal of Business Finance & Accounting (2004) 31(9-10) pp.1355-1387 RAE2008

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The desire to obtain competitive advantage is a motivator for implementing Enterprise Resource Planning (ERP) Systems (Adam & O’Doherty, 2000). However, while it is accepted that Information Technology (IT) in general may contribute to the improvement of organisational performance (Melville, Kraemer, & Gurbaxani, 2004), the nature and extent of that contribution is poorly understood (Jacobs & Bendoly, 2003; Ravichandran & Lertwongsatien, 2005). Accordingly, Henderson and Venkatraman (1993) assert that it is the application of business and IT capabilities to develop and leverage a firm’s IT resources for organisational transformation, rather than the acquired technological functionality, that secures competitive advantage for firms. Application of the Resource Based View of the firm (Wernerfelt, 1984) and Dynamic Capabilities Theory (DCT) (Teece and Pisano (1998) in particular) may yield insights into whether or not the use of Enterprise Systems enhances organisations’ core capabilities and thereby obtains competitive advantage, sustainable or otherwise (Melville et al., 2004). An operational definition of Core Capabilities that is independent of the construct of Sustained Competitive Advantage is formulated. This Study proposes and utilises an applied Dynamic Capabilities framework to facilitate the investigation of the role of Enterprise Systems. The objective of this research study is to investigate the role of Enterprise Systems in the Core Dynamic Capabilities of Asset Lifecycle Management. The Study explores the activities of Asset Lifecycle Management, the Core Dynamic Capabilities inherent in Asset Lifecycle Management and the footprint of Enterprise Systems on those Dynamic Capabilities. Additionally, the study explains the mechanisms by which Enterprise Systems sustain the Exploitability and the Renewability of those Core Dynamic Capabilities. The study finds that Enterprise Systems contribute directly to the Value, Exploitability and Renewability of Core Dynamic Capabilities and indirectly to their Inimitability and Non-substitutability. The study concludes by presenting an applied Dynamic Capabilities framework, which integrates Alter (1992)’s definition of Information Systems with Teece and Pisano (1998)’s model of Dynamic Capabilities to provide a robust diagnostic for determining the sustained value generating contributions of Enterprise Systems. These frameworks are used in the conclusions to frame the findings of the study. The conclusions go on to assert that these frameworks are free - standing and analytically generalisable, per Siggelkow (2007) and Yin (2003).

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The paper describes the development and application of a multiple linear regression model to identify how the key elements of waste and recycling infrastructure, namely container capacity and frequency of collection affect the yield from municipal kerbside recycling programmes. The overall aim of the research was to gain an understanding of the factors affecting the yield from municipal kerbside recycling programmes in Scotland. The study isolates the principal kerbside collection service offered by 32 councils across Scotland, eliminating those recycling programmes associated with flatted properties or multi occupancies. The results of a regression analysis model has identified three principal factors which explain 80% of the variability in the average yield of the principal dry recyclate services: weekly residual waste capacity, number of materials collected and the weekly recycling capacity. The use of the model has been evaluated and recommendations made on ongoing methodological development and the use of the results in informing the design of kerbside recycling programmes. The authors hope that the research can provide insights for the ongoing development of methods to optimise the design and operation of kerbside recycling programmes.

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Interaction with ecological models can improve stakeholder participation in fisheries management. Problems exist in efficiently communicating outputs to stakeholders and an objective method of structuring stakeholder differences is lacking. This paper aims to inform the design of a multi-user communication interface for fisheries management by identifying functional stakeholder groups. Intuitive categorisation of stakeholders, derived from survey responses, is contrasted with an Evidence-Based method derived from analysis of stakeholder literature. Intuitive categorisation relies on interpretation and professional judgement when categorising stakeholders among conventional stakeholder groups. Evidence-Based categorisation quantitatively characterises each stakeholder with a vector of four management objective interest-strength values (Yield, Employment, Profit and Ecosystem Preservation). Survey respondents agreed little in forming intuitive groups and the groups were poorly defined and heterogeneous in interests. In contrast the Evidence-Based clusters were well defined and largely homogeneous, so more useful for identifying functional relations with model outputs. The categorisations lead to two different clusterings of stakeholders and suggest unhelpful stereotyping of stakeholders may occur with the Intuitive categorisation method. Stakeholder clusters based on literature-evidence show a high degree of common interests among clusters and is encouraging for those seeking to maximise dialogue and consensus forming. © 2013 Elsevier Ltd.

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A size and trait-based marine community model was used to investigate interactions, with potential implications for yields, when a fishery targeting forage fish species (whose main adult diet is zooplankton) co-occurs with a fishery targeting larger-sized predator species. Predicted effects on the size structure of the fish community, growth and recruitment of fishes, and yield from the fisheries were used to identify management trade-offs among the different fisheries. Results showed that moderate fishing on forage fishes imposed only small effects on predator fisheries, whereas predator fisheries could enhance yield from forage fisheries under some circumstances.

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This thesis consists of an introductory chapter (essay I) and five more empirical essays on electricity markets and CO2 spot price behaviour, derivatives pricing analysis and hedging. Essay I presents the structure of the thesis and electricity markets functioning and characteristics, as well as the type of products traded, to be analyzed on the following essays. In the second essay we conduct an empirical study on co-movements in electricity markets resorting to wavelet analysis, discussing long-term dynamics and markets integration. Essay three is about hedging performance and multiscale relationships in the German electricity spot and futures markets, also using wavelet analysis. We concentrate the investigation on the relationship between coherence evolution and hedge ratio analysis, on a time-frequency-scale approach, between spot and futures which conditions the effectiveness of the hedging strategy. Essays four, five and six are interrelated between them and with the other two previous essays given the nature of the commodity analyzed, CO2 emission allowances, traded in electricity markets. Relationships between electricity prices, primary energy fuel prices and carbon dioxide permits are analyzed on essay four. The efficiency of the European market for allowances is examined taking into account markets heterogeneity. Essay five analyzes stylized statistical properties of the recent traded asset CO2 emission allowances, for spot and futures returns, examining also the relation linking convenience yield and risk premium, for the German European Energy Exchange (EEX) between October 2005 and October 2009. The study was conducted through empirical estimations of CO2 allowances risk premium, convenience yield, and their relation. Future prices from an ex-post perspective are examined to show evidence for significant negative risk premium, or else a positive forward premium. Finally, essay six analyzes emission allowances futures hedging effectiveness, providing evidence for utility gains increases with investor’s preference over risk. Deregulation of electricity markets has led to higher uncertainty in electricity prices and by presenting these essays we try to shed new lights about structuring, pricing and hedging in this type of markets.

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Double Degree. A Work Project presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA- School of Business and Economics and a Masters Degree in Management from Louvain School of Management

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The present investigation on “Coconut Phenology and Yield Response to Climate Variability and Change” was undertaken at the experimental site, at the Regional Station, Coconut Development Board, KAU Campus, Vellanikkara. Ten palms each of eight-year-old coconut cultivars viz., Tiptur Tall, Kuttiadi (WCT), Kasaragod (WCT) and Komadan (WCT) were randomly selected.The study therefore, reinforces our traditional knowledge that the coconut palm is sensitive to changing weather conditions during the period from primordium initiation to harvest of nuts (about 44 months). Absence of rainfall from December to May due to early withdrawal of northeast monsoon, lack of pre monsoon showers and late onset of southwest monsoon adversely affect the coconut productivity to a considerable extent in the following year under rainfed conditions. The productivity can be increased by irrigating the coconut palm during the dry periods.Increase in temperature, aridity index, number of severe summer droughts and decline in rainfall and moisture index were the major factors for a marginal decline or stagnation in coconut productivity over a period of time, though various developmental schemes were in operation for sustenance of coconut production in the State of Kerala. It can be attributed to global warming and climate change. Therefore, there is a threat to coconut productivity in the ensuing decades due to climate variability and change. In view of the above, there is an urgent need for proactive measures as a part of climate change adaptation to sustain coconut productivity in the State of Kerala.The coconut productivity is more vulnerable to climate variability such as summer droughts rather than climate change in terms of increase in temperature and decline in rainfall, though there was a marginal decrease (1.6%) in the decade of 1981-2009 when compared to that of 1951-80. This aspect needs to be examined in detail by coconut development agencies such as Coconut Development Board and State Agriculture Department for remedial measures. Otherwise, the premier position of Kerala in terms of coconut production is likely to be lost in the ensuing years under the projected climate change scenario. Among the four cultivars studied, Tiptur Tall appears to be superior in terms of reproduction phase and nut yield. This needs to be examined by the coconut breeders in their crop improvement programme as a part of stress tolerant under rainfed conditions. Crop mix and integrated farming are supposed to be the best combination to sustain development in the long run under the projected climate change scenarios. Increase in coconut area under irrigation during summer with better crop management and protection measures also are necessary measures to increase coconut productivity since the frequency of intensity of summer droughts is likely to increase under projected global warming scenario.

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The South West (S.W.) coast of India is blessed with a series of wetland systems popularly referred to as backwaters covering a total area of 46128.94 ha. These backwaters are internationally renowned for their aesthetic and scientific values including being a repository for several species fish and shell fishes. This is more significant in that three wetlands (Vembanad, Sasthamcotta and Ashtamudi) have recently been designated as Ramsar sites of international importance. Thirty major backwaters forming the crux of the coastal wetlands form an abode for over 200 resident or migratory fish and shellfish species. The fishing activities in these water bodies provide the livelihood to about 200,000 fishers and also provide full-time employment to over 50,000 fishermen. This paper describes the changes on the environmental and biodiversity status of selected wetlands, during 1994-2005 period. The pH was generally near neutral to alkaline in range. The salinity values indicated mixohaline condition ranging from 5.20-32.38 ppt. in the 12 wetlands. The productivity values were generally low in most of the wetlands during the study, where the gross production varied from 0.22 gC/m3/day in Kadinamkulam to 1.10 gC/m3/day in the Kayamkulam. The diversity of plankton and benthos was more during the pre-monsoon compared to the monsoon and post-monsoon periods in most of the wetlands. The diversity of plankton and benthos was more during the pre-monsoon compared to the monsoon and post-monsoon periods in most of the wetlands. The average fish yield per ha. varied from 246 kg. in Valapattanam to 2747.3 kg. in Azhikode wetland. Retting of coconut husk in most of the wetlands led to acidic pH conditions with anoxia resulting in the production of high amounts of sulphide, coupled with high carbon dioxide values leading to drastic reduction in the incidence and abundance of plankton, benthic fauna and the fishery resources. The major fish species recorded from the investigation were Etroplus suratensis, E. maculatus, Channa marulius, Labeo dussumieri, Puntius sp. Lutianus argentimaculatus, Mystus sp., Tachysurus sp. and Hemiramphus sp. The majority of these backwaters are highly stressed, especially during the pre monsoon period when the retting activity is at its peak. The study has clearly reflected that a more restrained and cautious approach is needed to manage and preserve the unique backwater ecosystems of South-west India