43 resultados para Refrigeration and refrigerating machinery

em Deakin Research Online - Australia


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Many nuclear and nucleolar small RNAs are accumulated as nonpolyadenylated species and require 3′-end processing for maturation. Here, we show that several genes coding for box C/D and H/ACA snoRNAs and for the U5 and U2 snRNAs contain sequences in their 3′ portions which direct cleavage of primary transcripts without being polyadenylated. Genetic analysis of yeasts with mutations in different components of the pre-mRNA cleavage and polyadenylation machinery suggests that this mechanism of 3"-end formation requires cleavage factor IA (CF IA) but not cleavage and polyadenylation factor activity. However, in vitro results indicate that other factors participate in the reaction besides CF IA. Sequence analysis of snoRNA genes indicated that they contain conserved motifs in their 3" noncoding regions, and mutational studies demonstrated their essential role in 3"-end formation. We propose a model in which CF IA functions in cleavage and polyadenylation of pre-mRNAs and, in combination with a different set of factors, in 3"-end formation of nonpolyadenylated polymerase II transcripts.

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The current work used discrete event simulation techniques to model the economics of quality within an actual automotive stamping plant. Automotive stamping is a complex, capital intensive process requiring part-specific tooling and specialised machinery. Quality control and quality improvement is difficult in the stamping environment due to the general lack of process understanding and the large number to interacting variables. These factors have prevented the widespread use of statistical process control. In this work, a model of the quality control techniques used at the Ford Geelong Stamping plant is developed and indirectly validated against results from production. To date, most discrete event models are of systems where the quality control process is clearly defined by the rules of statistical process control. However, the quality control technique used within the stamping plant is for the operator to perform a 100% visual inspection while unloading the finished panels. In the developed model, control is enacted after a cumulative count of defective items is observed, thereby approximating the operator who allows a number of defective panels to accumulate before resetting the line. Analysis of this model found that the cost sensitivity to inspection error is dependent upon the level of control and that the level of control determines line utilisation. Additional analysis of this model demonstrated that additional inspection processes would lead to more stable cost structures but these structures many not necessarily be lower cost. The model was subsequently applied to investigate the economics of quality improvement. The quality problem of panel blemishes, induced by slivers (small metal fragments), was chosen as a case stuffy. Errors of 20-30% were observed during direct validation of the cost model and it was concluded that the use of discrete event simulation models for applications requiring high accuracy would not be possible unless the production system was of low complexity. However, the model could be used to evaluate the sensitivity of input factors and investigating the effects of a number of potential improvement opportunities. Therefore, the research concluded that it is possible to use discrete event simulation to determine the quality economics of an actual stamping plant. However, limitations imposed by inability of the model to consider a number of external factors, such as continuous improvement, operator working conditions or wear and the lack of reliable quality data, result in low cost accuracy. Despite this, it still can be demonstrated that discrete event simulation has significant benefits over the alternate modelling methods.

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Coal handling is a complex process involving different correlated and highly dependent operations such as selecting appropriate product types, planning stockpiles, scheduling stacking and reclaiming activities and managing train loads. Planning these operations manually is time consuming and can result in non-optimized schedules as future impact of decisions may not be appropriately considered. This paper addresses the operational scheduling of the continuous coal handling problem with multiple conflicting objectives. As the problem is NP-hard in nature, an effective heuristic is presented for planning stockpiles and scheduling resources to minimize delays in production and the coal age in the stockyard. A model of stockyard operations within a coal mine is described and the problem is formulated as a Bi- Objective Optimization Problem (BOOP). The algorithm efficacy is demonstrated on different real-life data scenarios. Computational results show that the solution algorithm is effective and the coal throughput is substantially impacted by the conflicting objectives. Together, the model and the proposed heuristic, can act as a decision support system for the stockyard planner to explore the effects of alternative decisions, such as balancing age and volume of stockpiles, and minimizing conflicts due to stacker and reclaimer movements.

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The internet revolution has affected everybody in some way. Technologies used in business range from telephones to industry-specific machinery. Mostly though, business technology has come to mean the internet. In literature concerning innovation and the adoption of technology in business, research invariably centres on small to medium businesses (SI'v1Es), as these can be defined reasonably easily. Statistics on family businesses are limited, however, because family businesses are so difficult to categorize and define.

The Australian Family Business Survey of 1993 (Institute of Chartered Accountants) determined that family business is the largest form of business ownership in Australia and represents 83% of all business enterprises, although Basu (2004) believes that over two thirds of all world-wide businesses are owned or managed by families and around half of all businesses in Australia are family businesses. The Australian Institute of Management (AIM) (2004) states that the wealth of family and private businesses is estimated at $3.6 trillion and that family firms generate 50 per cent of Australia's employment growth, account for 40 per cent of Australia's private sector output, and are a seed bed for innovation and the information of large companies.

The difficulty in defining a family business is heightened because family businesses can take many forms ranging from sole traders to private companies to public companies. Hence, when talking about family business, you could be referring to the sole trader dealing with organic produce to an IT organisation employing hundreds of staff. Basu (2004) thinks that while ordinarily, in non-family businesses, the business and family domains remain separate, the key distinctive characteristic of family businesses is that family members work together for economic purposes. In other words, the family is not merely a social unit but also an economic unit. Craig and Lindsay (2002) believe that family involvement in the business is what makes the family business different... researchers, however, cannot seem to agree as to what constitutes 'family involvement' in a business so that it can be defined as a family business and that family business is ... a business that is governed and/or managed with the intention to shape and pursue the vision of the business held by a dominant coalition that is controlled by members of the same family or a small number of families in a manner that is potentially sustainable across generations of the family or families.

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This paper presents an idea of using solar powered adsorption ice making system as an alternative or an auxiliary way for the traditional ice storage air conditioning systems. A simple solar adsorption refrigeration system runs in intermittent cycle. It makes cooling effect at night, and the cooling effect can be stored for the day use. It fits in well with the cycle of the existing off-peak ice storage air conditioning system. On the top of green effect of the solar powered ice making system, the idea is specifically beneficial for places where the price of the off-peak electricity is not significantly lower than peak price. Based on our many years experience on the solar ice making systems, the paper discusses the technical feature of the solar ice making technology and the solutions we are working on to attack the problems which may have potential damage to application of the solar ice making system for air conditioning purposes.

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This paper presents a novel approach of applying both positive selection and negative selection to supervised learning for anomaly detection. It first learns the patterns of the normal class via co-evolutionary genetic algorithm, which is inspired from the positive selection, and then generates synthetic samples of the anomaly class, which is based on the negative selection in the immune system. Two algorithms about synthetic generation of the anomaly class are proposed. One deals with data sets containing a few anomalous samples; while the other deals with data sets containing no anomalous samples at all. The experimental results on some benchmark data sets from UCI data set repertory show that the detection rate is improved evidently, accompanied by a slight increase in false alarm rate via introducing novel synthetic samples of the anomaly class. The advantages of our method are the increased ability of classifiers in identifying both previously known and innovative anomalies, and the maximal degradation of overfitting phenomenon.

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Integral proteins in the outer membrane of mitochondria control all aspects of organelle biogenesis, being required for protein import, mitochondrial fission, and, in metazoans, mitochondrial aspects of programmed cell death. How these integral proteins are assembled in the outer membrane had been unclear. In bacteria, Omp85 is an essential component of the protein insertion machinery, and we show that members of the Omp85 protein family are also found in eukaryotes ranging from plants to humans. In eukaryotes, Omp85 is present in the mitochondrial outer membrane. The gene encoding Omp85 is essential for cell viability in yeast, and conditional omp85 mutants have defects that arise from compromised insertion of integral proteins like voltage-dependent anion channel (VDAC) and components of the translocase in the outer membrane of mitochondria (TOM) complex into the mitochondrial outer membrane.

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During spore formation in Bacillus subtilis, cell division occurs at the cell pole and is believed to require essentially the same division machinery as vegetative division. Intriguingly, although the cell division protein DivIB is not required for vegetative division at low temperatures, it is essential for efficient sporulation under these conditions. We show here that at low temperatures in the absence of DivIB, formation of the polar septum during sporulation is delayed and less efficient. Furthermore, the polar septa that are complete are abnormally thick, containing more peptidoglycan than a normal polar septum. These results show that DivIB is specifically required for the efficient and correct formation of a polar septum. This suggests that DivIB is required for the modification of sporulation septal peptidoglycan, raising the possibility that DivIB either regulates hydrolysis of polar septal peptidoglycan or is a hydrolase itself. We also show that, despite the significant number of completed polar septa that form in this mutant, it is unable to undergo engulfment. Instead, hydrolysis of the peptidoglycan within the polar septum, which occurs during the early stages of engulfment, is incomplete, producing a similar phenotype to that of mutants defective in the production of sporulation-specific septal peptidoglycan hydrolases. We propose a role for DivIB in sporulation-specific peptidoglycan remodelling or its regulation during polar septation and engulfment.

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To solve the leaking problem faced by current vacuum adsorption refrigeration systems, the authors have carried out a series of studies on the concept of raising the system's pressure to around atmospheric pressure with an inert gas (eg. Helium) as the pressure-adjusting agent. This paper presents the simulation of the performance oj the activated carbon-methanol adsorption refrigeration operating at near atmospheric pressure powered by solar energy. This simulation can be refereed in the prototype design.

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Sport video data is growing rapidly as a result of the maturing digital technologies that support digital video capture, faster data processing, and large storage. However, (1) semi-automatic content extraction and annotation, (2) scalable indexing model, and (3) effective retrieval and browsing, still pose the most challenging problems for maximizing the usage of large video databases. This article will present the findings from a comprehensive work that proposes a scalable and extensible sports video retrieval system with two major contributions in the area of sports video indexing and retrieval. The first contribution is a new sports video indexing model that utilizes semi-schema-based indexing scheme on top of an Object-Relationship approach. This indexing model is scalable and extensible as it enables gradual index construction which is supported by ongoing development of future content extraction algorithms. The second contribution is a set of novel queries which are based on XQuery to generate dynamic and user-oriented summaries and event structures. The proposed sports video retrieval system has been fully implemented and populated with soccer, tennis, swimming, and diving video. The system has been evaluated against 20 users to demonstrate and confirm its feasibility and benefits. The experimental sports genres were specifically selected to represent the four main categories of sports domain: period-, set-point-, time (race)-, and performance-based sports. Thus, the proposed system should be generic and robust for all types of sports.

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The Commonwealth departmental machinery of government is changed by using Orders in Council to create, abolish or change the name of departments. Since 1906 governments have utilised a particular form of Order in Council, the Administrative Arrangements Order (AAO), as the means to reallocate functions between departments for administration. After 1928 successive governments from Scullin to Fraser gradually streamlined and increasingly used the formal processes for the executive to change departmental arrangements and the practical role of Parliament, in the process of change, virtually disappeared. From 1929 to 1982, 105 separate departments were brought into being, as new departments or through merger, and 91 were abolished, following the merger of their functions in one way or another with other departments. These figures exclude 6 situations where the change was simply that of name alone. Several hundred less substantial transfers of responsibilities were also made between departments. This dissertation describes, documents and analyses all these changes. The above changes can be distilled down to 79 events termed primary decisions. Measures of the magnitude of change arising from the decisions are developed with 157.25 units of change identified as occurring during the period, most being in the Whitlam and Fraser periods. The reasons for the changes were assessed and classified as occurring for reasons of policy, administrative logic or cabinet comfort. 47.2% of the units of change were attributed to policy, 34.9% to administrative logic, 17% to cabinet comfort. Further conclusions are drawn from more detailed analysis of the change and the reasons for the changes.

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Legislation is demanding that our existing building stock be improved to a minimum of 4.0 Star AGBRS (Aust. Green Building Rating Scheme) energy standards. In the 'Green Building Fund' scheme for office buildings and other government incentives, retrofitting our existing building stock makes plain good sense. However, many of the stakeholders (owners, facilities managers, occupants) do not know where to begin to invest, for making these savings. This paperdemonstrates through two case studies, in government related  office buildihgs,how real energy savings were approached and obtained. It illustrates a process whereby preliminary and pretesting results lead to solutions of building ventilation, infiltration and comfort improvement. Furthermore, it discusses how post building performance testing results verified improvement as well as provided inputs to energy simulation, indicating where further invested improvements could be made.
One case study illustrates how the weatherisation of a building prevented a 1.5 million dollar retrofitting spending, costing the client less than one-tenth of the initial retrofitting cost. Another example demonstrates how over-engineering and incorrect ventilation concepts can cost the client up to 70% of their energy bill. Both papers involve real evidence-based pre and post measurement results in existing occupied buildings.