Design of scalar functional observers of order less than (v-1)

This paper presents a new method of designing scalar functional observers of order less than the well-known upper bound (ν - 1). A condition for the existence of observers of order p where 1 ≤ p ≤ (ν - 1) is given. A simple and effective algorithm for solving the constrained generalized Sylvester equation is proposed. Several numerical examples are given to illustrate the attractiveness of the design algorithm.

Design and simulation of a RF MEMS shunt switch for Ka and V bands and the impact of varying its geometrical parameters

RF MEMS plays an important role in microwave switching. The high performance of RF MEMS shunt such as high bandwidth, low insertion loss, and high isolation have made these switches well suitable for high performing microwave and millimeter wave circuits. This paper presents a RF MEMS shunt capacitive switch for Ka and V band application. This paper investigates the effect of various geometrical parameters on RF characteristics of the switch. The simulation results are presented and discussed.

Computer-aided design decision support: interfacing knowledge and information

Computer-aided design decision support has proved to be an elusive and intangible project for many researchers as they seek to encapsulate information and knowledge-based systems as useful multifunctional data structures. Definitions of ‘knowledge', ‘information', ‘facts', and ‘data' become semantic footballs in the struggle to identify what designers actually do, and what level of support would suit them best, and how that support might be offered. The Construction Primer is a database-drivable interactive multimedia environment that provides readily updated access to many levels of information aimed to suit students and practitioners alike. This is hardly a novelty in itself. The innovative interface and metadata structures, however, combine with the willingness of national building control legislators, standards authorities, materials producers, building research organisations, and specification services to make the Construction Primer a versatile design decision support vehicle. It is both compatible with most working methodologies while remaining reasonably future-proof. This paper describes the structure of the project and highlights the importance of sound planning and strict adhesion to library-standard metadata protocols as a means to avoid the support becoming too specific or too paradigmatic.

Energy efficient envelope design for high-rise apartments

The energy required to create a comfortable living environment in  high-density cities in hot and humid climates usually demands a substantial electricity usage with an associated environmental burden. This paper describes an integrated passive design approach to reduce the cooling requirement for high-rise apartments through an improved building envelope design. The results show that a saving of 31.4% in annual required cooling energy and 36.8% in the peak cooling load for the BASECASE apartment can be achieved with this approach. However, all the passive strategies have marginal effect on latent cooling load, often less than 1%.

Design of reduced-order scalar functional observers

In the existing literature, the existence conditions and design procedures for scalar functional observers are available for the cases where the observers’ order p is either p=1 or p=(v-1), where v is the observability index of the matrix pair (C,A). Therefore, if an observer with an order p=1 does not exist, the other available option is to use a higher order observer with p=(v-1). This paper shows that there exists another option that can be used to design scalar linear functional observers of the order lower than the well-known upper bound (v-1). The paper provides the existence conditions and a design procedure for scalar functional observers of order 0≤ p ≤2, and demonstrates the presented results with a numerical example.

Existence and design of reduced-order scalar functional observers

In the existing literature, the existence conditions and design procedures for scalar functional observers are available for the cases where the observers’ order p is either p=1 or p=(v-1), where v is the observability index of the matrix pair (C,A). Therefore, if an observer with an order p=1 does not exist, the other option is to use a high-order observer with p=(v-1). This paper provides the existence conditions and a design procedure for scalar functional observers of order 0≤p≤2, and demonstrates the presented results with a numerical example. where K, M, E, H and G are constant matrices to be designed. The problem of observing a scalar functional or multi functionals (z(t)∈Rk , k>1) of the state vector has been the subject of numerous papers, and different algorithms have been proposed (see, [1]-[13] and references therein). There are also papers that deal with the order reduction of multi-dimensional functional observers [9,10,12,13]. For scalar functional observers, a well-known Luenberger’s classic result [1] provides an upper bound on the order with p=(v-1). It is interesting to note here that, except for a recent result of Darouach [12,13], little results have been reported on the order reduction for scalar functional observers.

Role of multi-tenure reserve networks in improving reserve design and connectivity

Multi-tenure reserve networks aim to connect areas managed for biodiversity conservation across public and private land. This paper seeks to determine to what extent multi-tenure reserve networks improve the reserve design and connectivity of the public protected area estate, using three networks in southeastern Australia as case studies. Network configuration varied considerably and those networks with generally larger parcels tended to be better connected. On average, public land components were larger than private land components in all networks. Two networks had 18 components physically adjoining other network components while another had only 6 components adjoining. Importantly for two of the networks, the average distance between the nearest neighbouring component was significantly less than average distances between public protected areas in the subregion. Thus these multi-tenure reserve networks acted to enhance the existing public protected area estate by increasing the potential linkages in the landscape and therefore the viability of individual public protected areas.

A review of cashmere nutrition experiments with suggestions for improving their design and conduct

The scientific literature contains divergent views about the effects of nutrition on cashmere. The consequences of ignoring nutrition will be an increase in the number of goats suffering lower production, increased welfare risks and premature mortality. This review evaluated published reports to identify current knowledge and best practice in regard to the design and management of cashmere nutrition experiments. The ability of experiments to distinguish between treatments was evaluated based on their statistical evidence. Many experiments had serious deficiencies in their design, conduct and reporting. Six of 16 papers did not provide statistical information that would enable a reader to verify differences between treatments. For most experiments to detect nutrition affects at P < 0.05, they required a difference between treatments of 0.2–0.8 μm in cashmere mean fibre diameter and 15–42 g in clean cashmere production. Government Research Institutes research was characterised by more experienced authors conducting longer (P < 0.05) and larger (P < 0.05) experiments than those conducted by Universities. Much of the “debate” regarding the affects of nutrition on cashmere production arises from the misinterpretation of both experiments that did not detect statistically significant effects and of experiments that did detect statistically significant effects. Based on a comparison between experiments reporting responses to nutrition with those reporting no response, 13 design and management features were identified that are related to the ability of experiments to detect significant treatment affects. Methods must be adopted to reduce the variance in cashmere production within treatments, by using sufficient animals per treatment, and having replication to provide sufficient degrees of freedom to reduce error terms in analysis. The power of experimental designs should be evaluated before experiments commence. Cashmere production records from a previous full production year could be used as co-variants during statistical analyses but this requires that potential experimental goats are managed in one flock, without variations resulting from different grazing, reproduction or other management for a year prior to an experiment. It is preferable to use more productive and older goats, and goats that are used to handling, and to the conditions and feed to be used. Allocation of animals to treatments must take into account live weight. Nutrition treatments need to be sufficiently different to produce different growth curves. An appropriate control is needed such as live weight maintenance. Evidence of both nutrition intake and growth curves must be published with cashmere production data so the claims made can be verified by the actual responses. As cashmere production is an order of magnitude less than fibre production of Merino sheep or Angora goats and is more difficult to measure, the requirements for measurement, sampling and testing cashmere fleeces are summarised. The use of mid side cashmere patches to determine cashmere growth and quality is seriously biased and must be avoided, preferably by shearing goats prior to and at the end of experiments. In order to obtain higher fleece growth responses and improve the ability of experiments to detect treatment effects it is preferable to start cashmere growth experiments by midsummer and conduct experiments for at least 4 months. These requirements make it difficult for many university students to plan, undertake and complete long-term cashmere nutrition experiments without considerable management support. It is not possible for experiments to disprove the Null hypothesis regarding the effects of nutrition on cashmere production as they can only report a failure to detect treatment effects. Researchers and journals need to be more rigorous in providing statistical information including: degrees of freedom for error terms, treatment variances, standard error of differences or similar to enable readers to compare treatment effects. Publications that do not provide sufficient statistical information should be disregarded from future discussions. Claims that an experiment shows no responses to nutrition should be subject to rigorous examination using the issues identified in this review.