Air permeability of balsa core, and its influence on defect formation in resin infused sandwich laminates

Many large composite structures are manufactured using sandwich laminates to achieve high specific bending strength and stiffness. Examples include wind turbine blades, where self-weight becomes increasingly important as blade size increases. Resin infusion of three-dimensional sandwich laminates can result in complex resin flow paths, and subsequent defect formation, which are difficult to predict. The core material used for sandwich construction and its interaction with liquid resins may also influence the formation of defects, and in the case of balsa this effect can be used to reduce defect severity. In order to evaluate the effect of cored sandwich laminate construction on the formation of defects, this thesis concentrates on the characterisation of commonly used core materials and their interaction with liquid resin under high vacuum conditions. It also considers two numerical flow-modelling packages which are shown to be effective at the prediction of flow front convergence for monolithic laminate, but over-estimate defect severity when modelling air- permeable cored laminates. For balsa core, experiments indicate that the available pore space can act as sink for trapped air, which can aid the reduction of defects where multiple flow fronts converge due to the complexity of flow in sandwich laminates. Empirical data for air absorption and desorption rates in balsa core were obtained using a custom-designed experiment. Using these data a theoretical model was developed that can indicate available pore space, which can inform optimum processing conditions, such as time under vacuum. The diffusion coefficients obtained for air absorption and desorption in balsa are very similar, and lie in the middle of published ranges for hard woods at around 2 x 10 -7 m2/s. The methodology developed for this research project represents actual behaviour of air absorption/desorption during resin infusion, whilst other techniques do not, merely measuring diffusion of air through a sample not allowing for finite pore space. In consequence, infusion strategies can be planned more precisely because core/resin interaction is better understood. Knit line defect formation could be predicted with greater accuracy with suitably modified flow-modelling programs.Vestas Technologies, EPSR

Review of the market for Welsh organic meat, 2007

The supply situation for Welsh organic meat Organic production in Wales has been developing steadily in the last five years, with particular emphasis on organic cattle and sheep production. This was despite over-supply conditions in some sectors, notably dairy, following the very rapid growth in 1999/2000. Between the end of 2002 and end of 2005, the number of holdings increased by 12% to 688, and the certified land area increased by 29% to 71,000 hectares, of which more than 90% is grassland. Growth in Wales has exceeded other parts of the UK, reaching 5% of agricultural land by end 2005. More rapid growth is projected for 2006 and possibly 2007. Organic cattle and sheep numbers have also increased steadily between 2003 and 2005, with total cattle numbers increasing by 114% to 37,000, and total sheep numbers increasing 105% to 248,000, representing 17 and 36% of the end 2005 UK organic population respectively (compared with 16% of UK holdings and 12% of UK land area). Actual output of Welsh organic lamb and beef is more difficult to quantifying reflecting a continuing need for improved statistical data to support market development and the delivery of public policy. Best estimates are 4000-5000 cattle slaughtered as organic, but potentially available production (some in conversion and/or marketed as conventional) may be as high as 8000 head. For lambs, possible estimates based on availables source range from 25,000 to 57,000, but potentially available production may be as high as 100,000. Better data is available within the industry, but is regarded as highly commercially sensitive and was not made available to the review team. Organic farm gate prices for lamb and beef have remained relatively steady over the period, although the gap with conventional prices has closed as the conventional sector has recovered. Recent increases in demand for organic meat, and the temporary suspension of beef imports from Argentina (now restarted) have resulted in some strengthening of organic prices in 2006. Organic premium prices do not, however, fully compensate for the increased costs of production per kg of meat, so that organic producers, like their conventional counterparts, are being paid less than the real costs of production, and are relying on Tir Mynydd, agri-environmental and Single Farm Payments to subsidise continued production. This leaves the industry vulnerable to any decline in market conditions and will mean continuing pressure on smaller producers to leave the sector. The Welsh organic red meat sector currently relies on two main marketing approaches. The majority of lamb and beef (> 80%) is marketed through multiple retailers, supplied by two producer groups. The need for producer collaboration to ensure a strong price negotiating position with the multiple retailers is recognised and has been yielding benefits. The remainder of Welsh production is marketed on a smaller scale through specialist and local retailers and directly to consumers, through farmers markets, farm shops and via internet sales. There is currently virtually no exploitation of the potential export market (outside the UK) and still some difficulties with marketing light and store lambs as well as dairy bred calves and cull cattle, although various initiatives are in progress to address this. The demand situation for Welsh organic meat From a consumer demand perspective, the overall organic food market is in a healthy state: according to TNS data, it has just passed the £1 billion mark and has put on an extra £200 million in the last two years. Growth in the latest year was 10% and 17% in the previous year. There is still huge opportunity for growth by continuing to convert non-users and simply getting existing users to purchase more often. Household penetration of any organic product is very high at 84%. However, many organic products are purchased by default, and are not planned, as consumers were either satisfying other needs or simply because they liked the product. The positive aspect is that organic is a benefit to products that fall in this category and gives something extra. Current organic users are also interested in most of the ethical issues affecting society today. They regard themselves as connoisseurs of food and wine and as such purchase quality and premium food. As the main contributor to the sales within each of these sectors, this may dilute the expenditure they could make on organic food specifically. Heavy users in total organic represent 20% of buyers and they are responsible for 80% of organic expenditure. You would expect these heavy users to be committed organic purchasers but they only spend 5% of their grocery shopping spend on organic products. None of them are exclusive organic users and they cross-shop across the retail quality tiers (Organic/Premium/Healthy/Standard and Value) extensively. In organic meat the situation is the same. There are 0.3% of meat shoppers who buy only organic and a further 0.1% who buy only organic and premium. The rest shop across all the tiers. This does however identify some of the scope for expansion and these heavy users must be prime targets for increased organic usage. The red meat heavy organic shopper will buy over six times a year but medium users just under twice and light users just over once. This level of frequency is low and would suggest little commitment from the light and medium buyers and a very mixed cross-tier purchasing strategy for the heavy organic buyer. There are 3.2 million households in GB who buy organic meat but there are only 68,000 who only buy organic meat. This figure is lower than that for any of the individual species, indicating that someone who is a loyal organic user of one species is not loyal to organic, when purchasing the other species. (Households who only purchase organic: Beef 108,000, Lamb 269,000, Pork 112,000, Red meat 68,000). Heavy organic meat buyers will have one or two children and be in social class ABC1; they may be younger and older family groups. They are over represented in London, South, Scotland, East England and the South West. Whilst beef is the biggest organic red meat sector, it is only 1.5% of total beef sales; Lamb is the strongest at 2.2% of sales. Pork is a clear third with organic being 1% of sales. Organic meat in Wales is currently worth £2.4 million and is growing at 3% a year. This growth is coming from new entrants into the market. Total GB is growing 10% ahead of Wales but the household penetration in Wales is higher at 13.1% compared to 12.9% for GB. Growth in Wales is coming from all age groups and social classes, with the under 28’s and the C2 groups being particularly strong. This report also looks at the retail market in Great Britain for organic produce; there are additional opportunities within the foodservice sector where a number of specialist organic restaurants are appearing and interest shown by some of the large operators in including an organic alternative on their menus. There are also opportunities for export of organic Welsh lamb; currently some exports to Italy are carried out and there is further potential to exploit and develop this market. The potential for export of light organic lamb is restricted to southern European markets due to the small size and high seasonality of the product. Hybu Cig Cymru is have ongoing discussions with potential buyers in countries such as Portugal, Spain and Greece; however to date, the small volumes required have precluded meaningful developments due to logistical difficulties. Recommendations Despite the generally positive outlook from a demand perspective, there is a need to address some of the factors that might discourage producers from converting, including disruption to the Organic Farming Scheme, price levels that are below costs of production, and lack of markets for some livestock categories, in particular light lamb. To address this, there is a need for: • better statistical data on current and future production levels and market shares; • continued efforts to support producer groups in developing markets for organic meat and in seeking to achieve realistic prices; • continued development of alternative marketing channels, building on Welsh PGI and organic status, including local multiple and smaller retailers, public procurement, distribution hubs and exports; • consumer promotion initiatives and increased Welsh organic meat presence at trade fairs; • improved production systems, supported by effective research and development and knowledge transfer; • improved integration of effort between organic sector businesses and the agencies that support the development of the Welsh meat and organic sectors; • better linkage with the dairy, arable and horticulture sectors to benefit from complementarity relationships between the sectors at production, market development and promotional levels

Industrial pollution control down on the farm : integrated pollution prevention & control and intensive pig farming

Multi-medium pollution control has finally transcended the boundary from its roots in traditional manufacturing industry, and has entered the realm of intensive pig farming. This research has revealed the problems that face pig farmers when confronted by the Integrated Pollution Prevention & Control (IPPC) Directive (1996/61/EC). It has developed approaches that could assist intensive pig farmers in making important choices. A parallel study of the re-licensing of landfill facilities, an industry that is a veteran of licensing, has provided an ideal comparator. The literature on both industries was extensively searched for what was previously known. This has been supported by original research, including interviews with both landfill managers and pig farmers. These interviews were preceded by tours of landfill sites and pig farms - something that is seldom performed within the data collection stage of research where interviews are used. Differences between words and actions became apparent. These were analysed and their motivating factors considered. These discrepancies, evident through this verification process, serves to caution other researchers about the distortions that can arise when interviews alone are used. Identifying these discrepancies is also important because policy is often formulated using information collected though interview-based surveys. It may be the case that policy outcome deficit can result from the difference between words and actions.For decades farming has been moulded by society's desires in a similar vein to a nationalised industry. However, it is not a nationalised industry, but a collection of private individuals, family businesses, and larger companies. Multi-medium pollution control has been tried before. Integrated Pollution Control (IPC) was pioneered in England and Wales in 1991. Comparing the first years of that regime with the experiences that the Environment Agency are currently having reveals that many of the lessons have not been learnt. The funding available to the regulator, and the charges levied against the regulated are negotiated through compromises whereby environmental protection may be the loser. In this study, industry structures have been examined, revealing that the landfill industry is biased towards large operating companies. Re-licensing for the landfill industry is essentially a tightening of existing emission control, with relatively few additions. Landfill operators have the ability to pass costs on. Different experiences have been found between small and large landfill operators. Many small operators will go out of business. In this context it is noted that the structure of the intensive pig farming industry is biased towards smaller operators. Existing literature demonstrates that Small- and Medium-sized Enterprises (SMEs) have difficulty implementing environmental regulation. Through this study, this knowledge has been supplemented by close examination of two industries that have hitherto been omitted from the SME - environmental regulation debate. Industry characteristics are important factors that are here explored in detail, through inter-industry comparisons based upon size and through size comparisons within each industry. Within both industries large size is not just a scaled-up version of a small business. In fact the cultures and organisational structures are different. Essentially, intensive pig farmers have limited choices. Those at the small end of the scale may be able to de-stock and temporarily escape the threshold beyond which strict environmental controls come into play. Many at this scale may decide to retire and abandon pig farming. Alternatives for these farmers include pursuing niche or more specialised markets. Intermediate in size, Family Farming Businesses exhibit characteristics of both large and small businesses. Their future is a little more uncertain as there is a momentum to continue farming - a key characteristic which makes family businesses different. The largest businesses are better placed to implement the controls, or to challenge and to find the least cost compliance route. However, the competition from imports, and an inability to gain more for the meat they produce may force this category to increase the size of operation even further, so as to lower unit costs

Politics without Democracy: A Study of the New Principal Officials Accountability in Hong Kong

his Article seeks to discuss a range of issues related to the POAS. These issues include: The one country, two systems framework; The background to the introduction of the POAS; The fundamentals of the POAS; The notion of accountability pre- and post-POAS; An evaluation of executive government systems; The issues arising from the implementation of POAS; and, A best practice ministerial model for Hong Kong

Getting the Political Architecture Right

As Australia approaches the twenty-first century, it finds itself, like a number of other Anglo-centred countries in the western world, including Canada, in the grip of continuing economic trauma. There has been a marked relative (and absolute) slip in general economic performance. This paper focuses on the linkages between this phenomenon and Australia\u27s basic political architecture. It argues that, although renovation of Australian federalism is no panacea for these problems, there are linkages between Australia\u27s aged, formal, political structure and its recent economic performance. Lack of attention to the task of serious, systematic renovation is allowing the present outdated political structure to aggravate economic and social problems. The article concludes that a much more adventurous, long-term approach to the renovation of Australia\u27s political architecture is needed

Extension of the season of production and quality improvement of a range of vegetable crops.

End of Project ReportThe use of modules for propagation together with growing aids such as plastic covers after transplanting has brought forward significantly the start of the harvest season and improved yield and quality of several important brassicas including swede, cauliflower, broccoli and cabbage. These container grown plants (modules) enables crops to be grown for part of the life cycle under protection in early spring and transplanted outside in March/April when conditions become favourable.European Union Structural Funds (EAGGF