Modelling greenhouse gas emissions for Australian residential building construction

International pressure to reduce greenhouse gas emissions has forced many countries to look beyond 'demand side' measures. Several industry sectors are examining indirect requirements for energy and other resources that involve significant greenhouse gas emissions. The operation of buildings is responsible for approximately one quarter of greenhouse gas emissions in Australia. Moreover, he construction process consumes vast quantities of raw materials and complex goods and services each year. Each of the processes required for the provision of these products requires energy, and most of this is fossil fuel based. A national model of greenhouse gas emissions is required for residential building construction, to indicate where emissions reduction strategies should focus. A disaggregated input-output model is developed for the Australian residential building construction sector, and recommendations are made about how this model can be used in the development of policies of emissions mitigation for both the sector and individual residential buildings.

Hybrid life-cycle inventory for road construction and use

Life-cycle assessment (LCA) is a technique that is used worldwide by clients and their design team to assess the impact of
their projects on the environment. The main advantage of LCA is in supporting decision making with quantitative data. LCA inventories
can be either fully developed or streamlined. Fully developed LCAs are time-consuming and costly to prepare. Streamlined LCAs can be
used as an effective decision-making tool when considering environmental performance during the design process, but with a loss of
inventory completeness. Acknowledging the advantages and disadvantages of both types of LCA, this paper proposes a hybrid LCA
method that uses input-output data to fill in those gaps routinely left in conventional LCA inventories.

A linkage measure framework for the real estate sector

Linkage is one of the most important factors for gaining competitive advantage. Information on linkages is essential to understanding the structure of an economy, which is in turn important in formulating industry policies and business strategies. The hypothetical extraction method is used to measure the linkages by extracting a sector hypothetically from an economic system in the literature. In the previous research, however, the internal linkage (linkage within a sector) and sectoral linkages (linkage between two specific sectors) are ignored, and there is not a comprehensive framework to measure the linkages of a specific sector. Using the recently published Organisation for Economic Co-operation and Development input-output database at constant prices, this paper aims to resolve these two shortcomings and thereby propose a linkage measure framework to explore the linkages between the real estate sector and other sectors from a new angle. The relative and absolute linkages are termed and the total, backward, forward, internal and sectoral linkage indicators are formulated to investigate the linkages of the real estate sector from all directions. Empirical results show an increasing trend of these linkages, which confirms the increasing role of the real estate sector with economic maturity over the examined period. This framework also can be employed in other sectors.

Linkage measures of the construction sector using the hypothetical extraction method

The hypothetical extraction method (HEM) is used to extract a sector hypothetically from an economic system and examine the influence of this extraction on other sectors in the economy. Linkage measures based on the HEM become increasingly prominent. However, little construction linkage research applies the HEM. Using the recently published Organisation for Economic Co-operation and Development input-output database at constant prices, this research applies the HEM to the construction sector in order to explore the role of this sector in national economies and the quantitative interdependence between the construction sector and the remaining sectors. The output differences before and after the hypothetical extraction reflect the linkages of the construction sector. Empirical results show a declining trend of the total, backward and forward linkages, which confirms the decreasing role of the construction sector with economic maturity over the examined period from a new angle. Analytical results reveal that the unique nature of the construction sector and multifold external factors are the main reasons for the linkage difference between countries. Moreover, hypothesis-testing results consider statistically that the extraction structures employed in this research are appropriate to analyse the linkages of the construction sector.

Global factor trade with differentiated factor prices and factor intensities

Relaxing the assumption of internationally identical factor intensity techniques in the HOV model creates two challenges. First, computing actual factor intensity techniques of different countries requires detailed input-output tables and factor usage data, which are not always available. Second, determinants of the factor intensity technique differences across countries need to be identified. This paper explores the role of relative factor price differences in the determination of factor intensity technique differences across countries and proposes an inferring method that infers factor intensity techniques of different countries based on relative factor price differences. The HOV model is then modified accordingly.

Commerce mondial des facteurs de production quand les prix des facteurs sont différenciés et les intensités dans l'intensité d'utilisation des facteurs différentes. Relaxer le postulat de techniques à intensité identique de facteurs de production d'un pays à l'autre dans un modèle Heckscher-Ohlin-Vanek (HOV) pose deux défis. D'abord, mesurer les intensités en facteurs des techniques en place dans les divers pays réclame des tableaux interindustriels détaillés et des données sur l'utilisation des facteurs qui ne sont pas toujours disponibles. Ensuite, il faut identifier les déterminants des différences d'intensités en facteurs des techniques d'un pays à l'autre. Ce mémoire explore le rôle des différences dans les prix relatifs des facteurs dans la détermination des différences d'intensité en facteurs d'un pays à l'autre, et propose une méthode qui permet d'inférer les différences d'intensité en facteurs des techniques des divers pays à partir des différences dans les prix relatifs des facteurs. Le modèle HOV est alors modifié en conséquence.

Nonlinear identification of pneumatic servo-drive

Three nonlinear approaches to model the nonlinear pneumatic servo- drive are presented. The three nonlinear approaches are: (1) the multi input-single output (MISO) approach, which describes the single input-single output (SISO) nonlinear plant using a MISO linear representation which allows replacement of the nonlinear analysis by a linear one without approximation, and is studied in both time and frequency domains; (2) piecewise linearization, which systematically replaces, using artificial neural network, the nonlinear surface representing the plant in the hyper input-output space by a number of linear planes that are continuous over the boundaries between them; and (3) Adaptive Neuro-Fuzzy Inference System (ANFIS), in which the fuzzy rules are placed in a neural network structure, and which consequently utilizes neural networks learning rules to systematically tune the nonlinear fuzzy model. The superiority of these nonlinear models over the best model that can be developed using linear identification techniques is shown.

Deception: a tool and curse for security management

With the proliferation of electronic information systems over the last two decades, the integrity of the stored data and its uses have become an essential component of effective organisational functioning. This digitised format, used in input, output, processing, storage, and communication, has given those wishing to deceive new opportunities. This paper examines the nature of deception and its potential as a new security risk in the information age.

Embodied energy analysis of the refurbishment of a small detached building

Energy efficient design principles and the minimisation of operational energy requirements have been demonstrated in the refurbishment of a small existing residential building. Significant thought has been given to these areas, together with an emphasis on the minimisation of resource consumption and material wastage. However, less consideration has been given to the embodied energy of the additional materials, components and systems required to meet these aims. The additional embodied energy may reduce the advantages of minimising the operational energy consumption by extending the energy payback period beyond the life of the building. In general, the embodied energy of buildings and their products has been found to be significant, when national average input-output data is used to fill gaps in traditional life-cycle assessment inventories. Through the use of an input-outputbased hybrid embodied energy analysis, the embodied energy of this refurbished building has increased by 63% compared to the existing building, showing the impact that filling the gaps in traditional inventories can have on energy payback periods.

Predicting the rolling force in hot steel rolling mill using an ensemble model

Accurate prediction of the roll separating force is critical to assuring the quality of the final product in steel manufacturing. This paper presents an ensemble model that addresses these concerns. A stacked generalisation approach to ensemble modeling is used with two sets of the ensemble model members, the first set being learnt from the current input-output data of the hot rolling finishing mill, while another uses the available information on the previous coil in addition to the current information. Both sets of ensemble members include linear regression, multilayer perceptron, and k-nearest neighbor algorithms. A competitive selection model (multilayer perceptron) is then used to select the output from one of the ensemble members to be the final output of the ensemble model. The ensemble model created by such a stacked generalization is able to achieve extremely high accuracy in predicting the roll separation force with the average relative accuracy being within 1% of the actual measured roll force.

Economic analyses on multinational real estate and construction sectors

Both the construction and real estate sectors have been considered vital productive drivers for the economic development of a nation. Multinational economic analyses on these two sectors over a long period enable a better comprehension of their effects and interrelationships. Based on the recently published Organisation for Economic Co-operation and Development (OECD) input-output database at constant prices, this paper compares the real estate and construction sectors of six countries in terms of their shares in gross national product and gross national income. The push and pull effects of these two sectors onto the whole economy are further determined using forward and backward linkage indicators respectively. In addition, the interactions between themselves are formulated in terms of direct and total input parameters. This research provides a numerical approach to examine the economic influences and sectorial correlation of the real estate and construction sectors.

Assessing direct and indirect water requirements of construction

Australia is considered the driest populated continent in the world. Despite this, we consume the largest amount of water, per capita. While little of this water is used for the operation of buildings, buildings are now being designed to use less water. Additionally, rainwater collection and grey water recycling systems offer the potential to significantly reduce demand for fresh water. However, little is known about the water required directly and indirectly (ie., embodied in) construction materials and products. Embodied water comprises the water required directly for construction itself and the water consumed indirectly in the production and delivery of materials, products and services to construction. Water required directly for construction is likely to be insignificant compared to the indirect water required for the manufacture of construction materials and products (ie., through materials and other products required to support construction). There is currently a lack of research into embodied water requirements by the construction sector. The relationship between the embodied water and the operational water is also unknown, apart from a handful of studies based solely on national average statistics known as 'input-output' data. The aim of this paper is therefore to model the water required directly and indirectly by construction, integrating currently available public domain industry data with input-output data. The coverage of the industry data relative to the input-output data was evaluated for a typical commercial building, and was found to be very low.

Assessment of embodied energy analysis methods for the Australian construction industry

Environmental assessment of buildings typically focuses on operational energy consumption in an attempt to minimise building energy consumption. Whilst the operation of Australian buildings accounts for around 20% of total energy consumption nationally, the energy embodied in these buildings represents up to 20 times their annual operational energy. Many previous studies, now shown to be incomplete in system boundary or unreliable, have provided much lower values for the embodied energy of buildings and their products. Many of these studies have used traditional embodied energy analysis methods, such as process analysis and input-output (1-0) analysis. More recently, hybrid embodied energy analysis methods have been developed, combining these two traditional methods. These hybrid methods need to be compared and validated, as these too have been considered to have several limitations. This paper aims to evaluate a recently developed hybrid method for the embodied energy analysis of the Australian construction industry, relative to traditional methods. Recent improvements to this hybrid method include the use of more recent 1-0 data and th.fl inclusion of capital energy data. These significant systemic changes mean that a previous assessment of the methods needs to be reviewed. It was found that the incompleteness associated with process analysis has increased from 49% to 87%. These findings suggest that current best-practice methods of embodied energy analysis are sufficiently accurate for most typical applications. This finding is strengthened by recent improvements to the 1-0 model.

An assessment of the energy and water embodied in commercial building construction

Growing global concern regarding the rapid rate at which humans are consuming the earth’s precious natural resources is leading to greater emphasis on more effective means of providing for our current and future needs. Energy and fresh water are the most crucial of these basic human needs. The energy and water required in the operation of buildings is fairly well known. Much less is known about the energy and water embodied in construction materials and products. It has been suggested that embodied energy typically represents 20 times the annual operational energy of current Australian buildings. Studies have suggested that the water embodied in buildings may be just as significant as that of energy. As for embodied energy, these studies have been based on traditional analysis methods, such as process and input-output analysis. These methods have been shown to suffer from errors relating to the availability of data and its reliability. Hybrid methods have been developed in an attempt to provide a more reliable assessment of the embodied energy and water associated with the construction of buildings. This paper evaluates the energy and water resources embodied in a commercial office building using a hybrid analysis method based on input-output data. It was found that the use of this hybrid analysis method increases the reliability and completeness of an embodied energy and water analysis of a typical commercial building by 45% and 64% respectively, over traditional analysis methods. The embodied energy and water associated with building construction is significant and thus represents an area where considerable energy and water savings are possible over the building life-cycle. These findings suggest that current best-practice methods of embodied energy and water analysis are sufficiently accurate for most typical applications, but this is heavily dependent upon data quality and availability.

Reproducibility of digital evidence in forensic investigations

We present a three-component model of a digital investigation which comprises: determination of input-output layers, assignment of read and write operations associated with use of forensic tools, and time-stamping of read and write operations. This builds on work of several authors, culminating in the new model presented here which is generic, scalable and compatible with all functions in the system, and which is guaranteed to produce a high quality of reproducibility.