A novel cache mechanism

This cache mechanism is transparent but does not contain associative circuits. It does not rely on locality of reference of instructions or data. No redundant instructions or data are encached. Items in the cache are accessed without address arithmetic. A cache miss is detected by the simplest test; compare two bits. These features would result in faster access, higher hit rate, reduced chip area, and less power dissipation in comparison with associative systems of similar size

Complex-linear invariants of biochemical networks

The nonlinearities found in molecular networks usually prevent mathematical analysis of network behaviour, which has largely been studied by numerical simulation. This can lead to difficult problems of parameter determination. However, molecular networks give rise, through mass-action kinetics, to polynomial dynamical systems, whose steady states are zeros of a set of polynomial equations. These equations may be analysed by algebraic methods, in which parameters are treated as symbolic expressions whose numerical values do not have to be known in advance. For instance, an "invariant" of a network is a polynomial expression on selected state variables that vanishes in any steady state. Invariants have been found that encode key network properties and that discriminate between different network structures. Although invariants may be calculated by computational algebraic methods, such as Gr\"obner bases, these become computationally infeasible for biologically realistic networks. Here, we exploit Chemical Reaction Network Theory (CRNT) to develop an efficient procedure for calculating invariants that are linear combinations of "complexes", or the monomials coming from mass action. We show how this procedure can be used in proving earlier results of Horn and Jackson and of Shinar and Feinberg for networks of deficiency at most one. We then apply our method to enzyme bifunctionality, including the bacterial EnvZ/OmpR osmolarity regulator and the mammalian 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase glycolytic regulator, whose networks have deficiencies up to four. We show that bifunctionality leads to different forms of concentration control that are robust to changes in initial conditions or total amounts. Finally, we outline a systematic procedure for using complex-linear invariants to analyse molecular networks of any deficiency.Comment: 36 pages, 6 figure

A Control Systems Perspective to Condition Monitoring and Fault Diagnosis

Modern industrial processors, engineering systems and structures, have grown significantly in complexity and in scale during the recent years. Therefore, there is an increase in the demand for automatic processors, to avoid faults and severe break downs, through predictive maintenance. In this context, the research into nonlinear systems analysis has attained much interest in recent years as linear models cannot be used to represent some of these systems. In the field of control systems, the analysis of such systems is conducted in the frequency domain using methods of Frequency Response Analysis. Generalised Frequency Response Functions (GFRFs) and the Nonlinear Output Frequency Response Functions (NOFRFs) are Frequency Response Analysis techniques used for the analysis of nonlinear dynamical behaviour in the frequency domain. The problem of Condition Monitoring and Fault Diagnosis has been investigated in the perspective of modelling, signal processing and multivariate statistical analysis, data-driven methods such as neural networks have gained significant popularity. This is because possible faulty conditions related to complex systems are often difficult to interpret. In such a background, recently, a new data-driven approach based on a systems perspective has been proposed. This approach uses a controls systems analysis method of System Identification and Frequency Response Analysis and has been shown before as a potential technique. However, this approach has certain practical concerns regarding real-world applications. Motivated by these concerns in this thesis, the following contributions are put forward: 1. The method of evaluating NOFRFs, using input-output data of a nonlinear system may experience numerical errors. This is a major concern, hence the development of a method to overcome these numerical issues effectively. 2. Frequency Response Analysis cannot be used in its current state for nonlinear systems that exhibit severe nonlinear behaviour. Although theoretically, it has been argued that this is possible, even though, it has been impossible in a practical point of view. Therefore, the possibility and the manner in which Frequency Response Analysis can be conducted for these types of systems is presented. 3. Development of a System Identification methodology to overcome the issues of inadequately exciting inputs and appropriately capturing system dynamics under general circumstances of Condition Monitoring and Fault Diagnosis. In addition to the above, the novel implementation of a control systems analysis approach is implemented in characterising corrosion, crack depth and crack length on metal samples. The approach is applied to the data collected, using a newly proposed non-invasive Structural Health Monitoring method called RFID (Radio Frequency IDentification) wireless eddy current probing. The control systems analysis approach along with the RFID wireless eddy current probing method shows the clear potential of being a new technology in non-invasive Structural Health Monitoring systems

Soil Loss Estimation from Kelani River Catchment, Sri Lanka

Soil erosion from land surfaces is a major problem worldwide including Sri Lanka, especially in the Kelani river catchment. Kelani river basin is home to around 25% of the Sri Lankan population. The river is primary source of drinking water to over 4 million people living in the capital city - greater Colombo and over 10,000 industries and businesses depend on the natural resources and services provided by the basin. The land of Kelani river catchment is 2,342.05 km2 of this area 1,211.67 km2 used for agricultural purposes including rubber, tea and paddy and for the home gardens 390.29 km2 have been used. Another 269.38 km2 are occupied for forest cover together with lowland rainforests, sub-montane forests and montane forests. In addition, 24.04 km2 are covered with streams and rivers. To address these issues proper understating of soil erosion from the catchment is a vital requirement. Therefore, a study was conducted with the objective of estimating the soil erosion from the Kelani river watershed using universal soil loss equation (USLE). ArcGIS 10.2.2 commercial software was used to calculate the soil loss from the catchment. The results indicate that the average soil loss ranges between 0 to 715-ton ha-1, which is considerably high soil loss from the catchment. Average soil loss is highest in urbanized areas (715-ton ha-1) due to increases of the slope length factor and the lowest soil loss were found in the forested areas (0-ton ha-1). The soil loss from agricultural areas (481-ton ha-1), had average soil loss. Therefore, immediate soil erosion control measures must be applied to the residential areas. Also, sustainable development strategies should give major consideration for soil conservation. Since, the forested areas have the lowest erosion rates, forest cover in the upper catchments must be protected and expansion of the forests must be promoted. Therefore, this study concludes, estimation and modeling of soil erosion from the Kelani river catchment is an important tool for development of environment conservation and management plans with in the catchment.Keywords: Catchment, GIS, Kelani River, Soil loss USL

Analysis Of A Global Online Debate And The Development Of An Interaction Analysis Model For Examining Social Construction Of Knowledge In Computer Conferencing

This study attempts to find appropriate interaction analysis/content analysis techniques that assist in examining the negotiation of meaning and co-construction of knowledge in collaborative learning environments facilitated by computer conferencing. The authors review strengths and shortcomings of existing interaction analysis techniques and propose a new model based on grounded theory building for analyzing the quality of CMC interactions and learning experiences. This new Interaction Analysis Model for Examining Social Construction of Knowledge in Computer Conferencing was developed after proposing a new definition of "interaction" for the CMC context and after analyzing interactions that occurred in a Global Online Debate. The application of the new model for analysis of collaborative construction of knowledge in the online debate and in a subsequent computer conference are discussed and future research suggested

The horofunction boundary of the Hilbert geometry

We investigate the horofunction boundary of the Hilbert geometry defined on an arbitrary finite-dimensional bounded convex domain D. We determine its set of Busemann points, which are those points that are the limits of `almost-geodesics'. In addition, we show that any sequence of points converging to a point in the horofunction boundary also converges in the usual sense to a point in the Euclidean boundary of D. We prove that all horofunctions are Busemann points if and only if the set of extreme sets of the polar of D is closed in the Painleve-Kuratowski topology.Comment: 24 pages, 2 figures; minor changes, examples adde

Long term trend of selected halogenated hydrocarbons

The so-called 'Library of Background Air' at the Oregon Graduate Institute was used to determine the trend in volume mixing ratios of selected halogenated hydrocarbons in the time period 1977-1989. This library consists of background air samples most of them taken at Cape Meares (Oregon). For storage stainless steel containers are used. Tests have shown the gases under consideration to be stable in these containers. Analyses using a GC/MS-system were performed for the CFCs 11, 12, 12B1 (HALON 1211, CBrClF2), 22, 113, 114 and CH3Cl, CH3Br, CH3CCl3, CCl4. The advantage of this unique investigation: different aged air samples are analyzed at the same time with the same instrument. No calibrations or intercalibrations are needed. All data are presented in normalized mixing ratios versus time. We discuss the results, derive rate constants and present a formula to describe the nonlinear increases