Planar receiver placement for unique emitter localization for indoor applications

This paper investigates two independent approaches to verify the necessary and sufficient condition to guarantee a unique solution for a passive emitter localization system based on time difference of arrival measurements from an
array of sensors.

A review of the scope of scientific studies relating indoor environment and student performance

In 2006-7 the Australian government will invest $9.3 billion in state government and nongovernment educational facilities (DEST 20061). One area of particular interest to both government and school designers is maximising this investment through providing students with healthy and
productive indoor learning environments. The lack of post-occupancy evaluations carried out in schools (Lackney 2001) means that designers are reliant on “best practice” indoor environment quality guidelines developed primarily from scientific studies. The problem with scientific evaluation is that often the complexity of the influences upon student performance is simplified in order to gather information, rather than necessarily providing a more holistic and realistic explanation of any improved outcomes. This paper examines the scope of various studies of classroom indoor environment qualities that have thus far contributed to current understanding of their impact on student learning outcomes. The review demonstrates the lack of comprehensive research into the full range of influences on student performance and offers a better understanding of the limitations of knowledge about indoor environment qualities. This information provides valuable input to research development and post-occupancy evaluation that can better integrate the full range of influences upon students of school facilities and test the assumptions made about “best practice”.

Indoor environment quality and occupant productivity in the CH2 building

This paper presents a summary of the results from a post-occupancy evaluation study on indoor environment quality (lEO) and occupant health, wellbeing and productivity in the Council House 2 (CH2) building, which is owned and occupied by the City of Melbourne. This case study has highlighted that the productivity of office building occupants can potentially be enhanced through good building design, and provision of a high quality, healthy, comfortable and functional interior environment, that takes account of basic occupant needs.

Combining image regions and human activity for indirect object recognition in indoor wide-angle views

Traditional methods of object recognition are reliant on shape and so are very difficult to apply in cluttered, wideangle and low-detail views such as surveillance scenes. To address this, a method of indirect object recognition is proposed, where human activity is used to infer both the location and identity of objects. No shape analysis is necessary. The concept is dubbed 'interaction signatures', since the premise is that a human will interact with objects in ways characteristic of the function of that object - for example, a person sits in a chair and drinks from a cup. The human-centred approach means that recognition is possible in low-detail views and is largely invariant to the shape of objects within the same functional class. This paper implements a Bayesian network for classifying region patches with object labels, building upon our previous work in automatically segmenting and recognising a human's interactions with the objects. Experiments show that interaction signatures can successfully find and label objects in low-detail views and are equally effective at recognising test objects that differ markedly in appearance from the training objects.

Indoor location prediction using multiple wireless received signal strengths

This paper presents a framework for indoor location prediction system using multiple wireless signals available freely in public or office spaces. We first propose an abstract architectural design for the system, outlining its key components and their functionalities. Different from existing works, such as robot indoor localization which requires as precise localization as possible, our work focuses on a higher grain: location prediction. Such a problem has a great implication in context-aware systems such as indoor navigation or smart self-managed mobile devices (e.g., battery management). Central to these systems is an effective method to perform location prediction under different constraints such as dealing with multiple wireless sources, effects of human body heats or mobility of the users. To this end, the second part of this pa- per presents a comparative and comprehensive study on different choices for modeling signals strengths and prediction methods under different condition settings. The results show that with simple, but effective modeling method, almost perfect prediction accuracy can be achieved in the static environment, and up to 85% in the presence of human movements. Finally, adopting the proposed framework we outline a fully developed system, named Marauder, that support user interface interaction and real-time voice-enabled location prediction.

Thermal comfort of multiple user groups in indoor aquatic centres

Aquatic centres are popular recreational facilities in Australia and other developed countries. These buildings have experienced exponential demand over the past few decades. The growing desire for better indoor environmental quality in aquatic centres has resulted in a marked increase in energy consumption in this sector. With the existence of multiple user groups, achieving thermal comfort has always been challenging. Even though several thermal comfort studies are conducted in other building types, such studies are very limited with respect to aquatic centres. This paper analyses the thermal comfort conditions of various user groups in seven aquatic centres in Australia. Comfort measurements are performed through monitoring environmental parameters and surveying swimmers, staff and spectators. The results revealed the variation of air temperatures among the buildings, resulting in high level of thermal discomfort for the spectators and staff in some of the buildings. The thermal sensation of the staff and spectators had good correlation with the indoor temperatures and PMVs. Altering temperature settings according to the seasons will help to improve the comfort with respect to the adaptation and expectation of the occupants.

Investigating energy and indoor environmental performance of aquatic centres

Aquatic centres are popular recreational facilities in Australia and other developed countries. These buildings have experienced exponential demand over the past few decades. The growing desire for better indoor environmental quality in aquatic centres has resulted in a marked increase in energy consumption in this sector. Community expectations in relation to aquatic centres are rising and these spaces are associated with wellness and health. Energy consumption in indoor swimming pool buildings is high due to the high indoor air temperatures, increased ventilation heat losses and the need to disinfect water. This study investigates the energy consumption and indoor environmental quality of seven aquatic centres in Australia. The construction and various energy consuming systems of the facilities are analysed and compared against the energy consumption. Thermal comfort data is collected through measuring the indoor environmental parameters. Building envelopes were found to be leaky in most of the buildings resulting in energy wastage. The main indicators for energy consumption were gross floor area, area of pool surface, and number of visitors. It was found that the set point temperatures were significantly high in some of the buildings resulting in high level of discomfort for the spectators and staff.

Characterising indoor air temperature and humidity in Australian homes

Information about indoor air temperatures in residential buildings is of interest for a range of reasons, e.g. the health and comfort of occupants, energy demand for space heating and cooling. To date there have been few long term studies that measure and characterise indoor air temperatures in Australian homes. New primary research undertaken by the authors measured temperatures in 273 homes over the period 2011 to 2014 in seven climate zones, from Melbourne in the south to Cairns in the north of Australia. Humidity data was also collected in 20 homes. This paper is a description of the data collected and the subsequent analysis.

Indoor temperatures were compared with outdoor temperatures and a mathematical model was fitted to the data. In general, monthly average indoor temperatures were found to be 2 degreesC higher than monthly average outdoor temperatures, apart from periods with consistently cold weather, where the monthly average outdoor temperature was less than 20 degreesC, which were found to have larger differences. The indoor temperature model developed has been compared with data measured by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in 438 homes in three Australian cities. The model developed using project measurements are highly consistent with the CSIRO data.

Further data collection compared indoor and outdoor humidity in 20 houses in Sydney and Melbourne. The indoor humidity ratio was found to be, on average, slightly higher than outdoors, but indoor levels generally track outdoor levels quite closely. This is likely due to the high air exchange rate in most houses.

Heuristics-based Indoor positioning systems: a systematic literature review

Context: Many heuristics-based indoor positioning approaches havebeen developed to enhance positioning estimation. However, thereis no comprehensive survey of these heuristics information and methods. 

Applying the adaptive model of comfort

This note is directed to one major aspect of the comfort of building occupants – namely, thermal comfort. Even though it may be difficult to isolate thermal sensations from the whole of comfort itself, humans have a strong physiological connection with their thermal environment. Our thermal perceptions and sensations often vary greatly, especially between our indoor and outdoor environments. We may be totally comfortable lounging under a shade cloth on a 35°C day with a stiff breeze enveloping our body, but would never tolerate similar conditions indoors. Such divergent perceptions of the same thermal stimulus across differing contexts raise countless questions about just what the determinants of thermal comfort actually are, and how they may be managed against the demands for an environmentally responsive architecture.

Degradation of VOCs by phototcatalytic oxidation reactor using TiO2 pellets

Volatile Organic Compounds (VOCs) are air pollutants that come from burning fossil fuels and industrial emissions. They have potentially adverse health effects being carcinogenic and highly persistent in the environment. The use of photocatalytic oxidation to remove VOCs has the potential to be applied in indoor air quality improvement and industrial emission control. A fixed bed photocatalytic reactor was designed and built. UV black light lamps were installed in the reactor to provide a source of UV radiation. A non-film titania media as pellets were placed on the three fixed beds within the reactor. Toluene and acetone were used as indicators of VOCs during the experiment. With a flow rate of 12.75l/min, the oxidation efficiencies were obtained at four different concentrations of acetone laden gas streams ranging from 40ppm to 250ppm. It was found that the lower the acetone concentration of the untreated inlet gas, the higher the oxidation efficiency. The oxidation efficiency was in the range of 40–70% for various concentrations of untreated gases. Two concentrations of toluene laden gas stream were also tested using the same reactor. The oxidation efficiencies were found as 50% for 120ppm toluene gas and 45% for 300ppm toluene gas. It was found that the times required for toluene to reach oxidization equilibrium have been halved than for acetone gas stream. Other parameters such as flow rate and UV intensity were also altered to see their effects on the oxidation efficiency. A full spectrum scan was carried out using a Bio-rad Infrared spectrometer. It was found that the main components of the treated gas stream from the outlet of the reactor were CO2 and water along with small amount of untreated acetone. The suspected intermediates of aliphatic hydrocarbons and CO were found in very minimal amounts or undetectable. The research experiments supported that the TiO2 pellets can work effectively in a fixed bed photocatalytic reactor and achieve significant oxidation efficiencies for degradation of toluene and acetone as indicators of VOCs.

Node localization using mobile robots in delay-tolerant sensor networks

We present a novel scheme for node localization in a Delay-Tolerant Sensor Network (DTN). In a DTN, sensor devices are often organized in network clusters that may be mutually disconnected. Some mobile robots may be used to collect data from the network clusters. The key idea in our scheme is to use this robot to perform location estimation for the sensor nodes it passes based on the signal strength of the radio messages received from them. Thus, we eliminate the processing constraints of static sensor nodes and the need for static reference beacons. Our mathematical contribution is the use of a Robust Extended Kalman Filter (REKF)-based state estimator to solve the localization. Compared to the standard extended Kalman filter, REKF is computationally efficient and also more robust. Finally, we have implemented our localization scheme on a hybrid sensor network test bed and show that it can achieve node localization accuracy within 1m in a large indoor setting.