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Control Projects (control + project)
Selected AbstractsDetermining controller benefits via probabilistic optimizationINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 7-9 2003Y. Zhou Abstract For the most part, process control research has focussed on the synthesis and tuning of controllers, which has provided a plethora of techniques that can address virtually any application. With each new control technique, a steady stream of ,successful' application results are generated and reported. Recently, a considerable number of control researchers have turned their attention to assessing the performance of installed control systems and to the diagnosis of controller performance problems. Despite successes in the areas of controller synthesis, tuning and performance analysis, almost no research has addressed the fundamental issue of determining whether the economic performance gains that are expected accrue from a proposed process control project are sufficient to justify its execution. The work presented here proposes an optimization-based technique for calculating the expected economic performance of a given control system; a method, which is analogous to analysis of variance, for determining the expected economic benefit that will arise from a particular controller improvement effort; and a sensitivity analysis approach for determining the effect of specific assumptions on control system improvement decisions. Copyright © 2003 John Wiley & Sons, Ltd. [source] Molecular epidemiology of rubella virus in Asia: Utility for reduction in the burden of diseases due to congenital rubella syndromePEDIATRICS INTERNATIONAL, Issue 2 2004Shigetaka Katow AbstractBackground:,Rubella is a mild disease mainly of infants, involving a rash and a fever. However, when women who have no immunity to rubella are infected during the early stage of pregnancy, their babies are often born with congenital rubella syndrome (CRS), which is characterized by a few disorders including deafness, cataracts and heart malformations. To prevent CRS, several strains of live attenuated rubella vaccine have been developed and introduced into immunization programs in many countries. In most Asian countries except Japan, Singapore and Taiwan, rubella remains uncontrolled, and the burden of diseases from CRS is high. In order to develop a control program to reduce the number of CRS cases in Asian countries, it is necessary to conduct a survey of rubella and CRS cases, and to then determine the genotype of the circulating rubella virus in each country. Methods:,Cases of rubella and CRS, based on national reporting systems or active surveillance in the Asian countries, are summarized. Sequences of the E1 gene of the virus isolates from the Asian countries were compared by phylogenic analysis. Results:,Recent studies of the molecular epidemiology of rubella virus worldwide revealed that there are two genotypes, and that genotype I is circulating almost worldwide, while genotype II is an Asian prototype restricted to the Asian continent. Genotype I viruses fall into a number of groups, some of which are geographically localized. Antigenically these two genotypes are cross-reactive and immunization with either virus results in immunity to all rubella viruses. Discussion:,The hypotheses that rubella virus has evolved on the Asian continent is proposed. The World Health Organization (WHO) has recognized that a rubella immunization program can be combined with the measles immuization program. Inclusion of rubella in the expanded program of immunization (EPI) of measles would be ideal in Asian countries, as it would be efficient and cost effective to administer one injection containing a three-combined vaccine (MMR). It would also be desirable given that WHO require laboratory tests to confirm the presence of measles or rubella as part of it's measles control project, because rubella is often misdiagnosed as measles. [source] Modelling the benefits of American Mink Mustela vison management options for terns in west ScotlandIBIS, Issue 2008NORMAN RATCLIFFE American Mink Mustela vison is a semi-aquatic predator that has invaded the west coast of Scotland and many of its associated islands. We developed a GIS model of their potential range based on their dispersal abilities and habitat use, which revealed that most islands in west Scotland are accessible to Mink, and that these host a large proportion of the region's Common Sterna hirundo and Arctic Terns S. paradisaea. Mink are predators on tern eggs and chicks, and statistical modelling of long-term productivity data demonstrated that unprotected sites within their range have an average productivity of 0.33 chicks per pair, whereas that at sites where Mink were trapped was 253% higher. We assessed the benefits of current Mink control projects for terns in the Western Isles and the remainder of west Scotland using a population modelling approach. This showed that both projects delivered considerable benefits for Common Terns, because a large proportion of their numbers were within the area of the control programmes and in sites that would be accessible to Mink if no control were in operation. For Arctic Terns, the benefits were less clear, as a larger proportion of their numbers were outside the control areas, and many of these were in sites isolated from, or unsuitable for, Mink. We discuss the implications of these findings for future strategic planning of Mink management in west Scotland. [source] Assessment of Ceratitis capitata (Diptera, Tephritidae) pupae killed by heat or cold as hosts for rearing Spalangia cameroni (Hymenoptera: Pteromalidae)ANNALS OF APPLIED BIOLOGY, Issue 2 2010J. Tormos In this work, we study the suitability of using dead medfly Ceratitis capitata pupae, killed by heat- or cold-shock, for the mass rearing of Spalangia cameroni, a pupal parasitoid of key pests. 100% mortality of medfly pupae could be accomplished with cold-shock at ,20°C for 60 min or with heat-shock at 55°C for 30 min. Neither parasitism percentage nor sex ratio of the offspring differed significantly among heat-shocked, cold-shocked and untreated pupae. In addition, there was no significant difference in the percentage of parasitoids that aborted (,, or ,,) among pupal treatments. Some of the pupae were covered with peat because the third larval instar of the medfly buries itself before pupation. However, the buried pupae were not parasitised at a greater or lesser rate than those not covered with peat. The percentage of parasitism was also unaffected by whether the pupae had been killed recently or had been stored at between 4°C and 6°C over 15 or 30 days. The use of dead hosts and later storage permitted the following: (a) the use of hosts over long periods of time; (b) a rapid increase in parasitoid numbers and (c) the availability of pupae killed at the most suitable postpupation times for the production of parasitoids. Furthermore, in biological control projects, the use of dead parasitised pupae in the field avoids the risk of enhancing the pest and allows an increase in parasitism in the field through the use of pupae treated with cold- or heat-shock. [source] Rearing and release of Homichloda barkeri (Jacoby) (Coleoptera: Chrysomelidae: Alticinae) for the biological control of prickly acacia, Acacia nilotica ssp. indica (Mimosaceae) in AustraliaAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 3 2003Catherine J Lockett Abstract Prickly acacia, Acacia nilotica ssp. indica, a major weed of the Mitchell Grass Downs of northern Queensland, has been the target of biological control projects since the 1980s. The striped leaf-feeding beetle, Homichloda barkeri (Coleoptera: Chrysomelidae: Alticinae), was the third insect approved for release for the control of this weed in Australia. However, mass rearing this insect under glasshouse conditions proved to be difficult and time consuming as there were problems associated with low egg-hatching rates and poor larval survival. Eggs in diapause were stimulated to hatch by repeated wetting and drying. Larvae were fed on potted prickly acacia plants in cages. Late-instar larvae were collected and transferred to a mix of sand, peat moss and vermiculite for pupation and adult emergence. Over 10 500 adults were released at 28 sites in north Queensland between November 1996 and December 1999. Initial releases of insects confined to gauze cages resulted in limited adult survival, oviposition and development of first-generation larvae. First-generation larvae were observed at two sites where cages were not used. However, later inspections of release sites, including those made in April and December 2000, April 2001 and late March 2002, failed to find any trace of the insect, which is assumed to have failed to establish. Possible reasons for this failure are discussed. [source] | ||||||||||