Accelerating linear causal model discovery using hoeffding bounds

Efficiently inducing precise causal models accurately reflecting given data sets is the ultimate goal of causal discovery. The algorithms proposed by Dai et al. has demonstrated the ability of the Minimum Message Length (MML) principle in discovering Linear Causal Models from training data. In order to further explore ways to improve efficiency, this paper incorporates the Hoeffding Bounds into the learning process. At each step of causal discovery, if a small number of data items is enough to distinguish the better model from the rest, the computation cost will be reduced by ignoring the other data items. Experiments with data set from related benchmark models indicate that the new algorithm achieves speedup over previous work in terms of learning efficiency while preserving the discovery accuracy.

Encoding, ensemble and accelerating strategies for linear causal model discovery

This thesis made outstanding contribution in automating the discovery of linear causal models. It introduced a highly efficient discovery algorithm, which implements new encoding, ensemble and accelerating strategies. Theoretic research and experimental work showed that this new discovery algorithm outperforms the previous system in both accuracy and efficiency.

Microscopic / telescopic (universes unfold)

This exhibition was inspired by lens based observation; what is observed through the microscope – plankton and single cell organisms – finds its origin in what is observed through the telescope – stars and galaxies. The project explores two spatially divergent contexts. Artist, Melinda Capp explores the micro-scopic with porcelain objects, artist books and images derived microscopes and Daniel Armstrong references the macro-scopic with video, photography, lens based objects and installation of interactive sculpture / optical instruments to create an experiential connection between celestial phenomena/images and the viewer.

Pd embedded in porous carbon (Pd@CMK-3) as an active catalyst for Suzuki reactions: accelerating mass transfer to enhance the reaction rate

Heterogeneous catalysts are promising candidates for use in organic reactions due to their advantages in separation, recovery, and environment compatibility. In this work, an active porous catalyst denoted as Pd embedded in porous carbon (Pd@CMK-3) has been prepared by a strategy involving immersion, ammoniahydrolysis, and heating procedures. Detailed characterization of the catalyst revealed that Pd(0) and Pd(II) species co-exist and were embedded in the matrix of the porous carbon (CMK-3). The as-prepared catalyst has shown high activity toward Suzuki reactions. Importantly, if the reaction mixture was homogenized by two minutes of ultrasonication rather than magnetic stirring before heating, the resistance to mass transfer in the pore channels was significantly reduced. As a result, the reactions proceeded more rapidly and a four-fold increase in the turnover frequency (TOF) could be obtained. When the ultrasonication was employed throughout the entire reaction process, the conversion could also exceed 90% even without the protection of inert gas, and although the reaction temperature was lowered to 30 °C. This work provides a method for fabricating highly active porous carbon encapsulated Pd catalysts for Suzuki reactions and proves that the problem of mass transfer in porous catalysts can be conveniently resolved by ultrasonication without any chemical modification being necessary.[Figure not available: see fulltext.] © 2014 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

Selective visuo-haptic rendering of heterogeneous objects in 'parallel universes'

 Haptic rendering of complex models is usually prohibitive due to its much higher update rate requirement compared to visual rendering. Previous works have tried to solve this issue by introducing local simulation or multi-rate simulation for the two pipelines. Although these works have improved the capacity of haptic rendering pipeline, they did not take into consideration the situation of heterogeneous objects in one scenario, where rigid objects and deformable objects coexist in one scenario and close to each other. In this paper, we propose a novel idea to support interactive visuo-haptic rendering of complex heterogeneous models. The idea incorporates different collision detection and response algorithms and have them seamlessly switched on and off on the fly, as the HIP travels in the scenario. The selection of rendered models is based on the hypothesis of “parallel universes”, where the transition of rendering one group of models to another is totally transparent to users. To facilitate this idea, we proposed a procedure to convert the traditional single universe scenario into a “multiverse” scenario, where the original models are grouped and split into each parallel universe, depending on the scenario rendering requirement rather than just locality. We also proposed to add simplified visual objects as background avatars in each parallel universe to visually maintain the original scenario while not overly increase the scenario complexity. We tested the proposed idea in a haptically-enabled needle thoracostomy training environment and the result demonstrates that our idea is able to substantially accelerate visuo-haptic rendering with complex heterogeneous scenario objects.

Petrov type I electric silent universes must possess symmetries: G1, G2 or G3

We prove that all Petrov type I, silent universe solutions of Einstein's field equations with a zero cosmological constant must possess symmetries: G1, G2 or G3.

Accelerating mathematics learners : what counts?

This article elaborates on my statements quoted in The Age October 2014 article 'More students take on VCE mathematics subject early'. (http://theage.com.au/victoria/more-students-take-on-vce-subjects-early-20141024-11b4rv.html). This article was about accelerating mathematics students by allowing them to take year 11 Mathematics subjects in year 10, and year 12 Mathematics subjects in year 11. My statements were 'Although 'taking on Year 12 subjects early could help students prepare for the workload once they reach their final year ... based on my research and teaching experience, you don't take on early those subjects that are going to be key to your university studies' because 'going early means you are going to rely much more heavily on learning things faster.

Enabling electronic medicine at Kiwicare : the case of video conferencing adoption for psychiatry in New Zealand

Telemedicine emerges as a viable solution to New Zealand health providers in reaching out to rural patients, in offering medical services and conducting administrative meetings and training. No research exists about adoption of telemedicine in New Zealand. The purpose of this case study was to explain factors influencing adoption of telemedicine utilizing video conferencing technology (TMVC) within a New Zealand hospital known as KiwiCare. Since TMVC is part of IT, tackling it from within technological innovation literature may assist in providing an insight into its adoption within KiwiCare and into the literature. Findings indicate weak presence of critical assessment into technological innovation factors prior to the adoption decision, thereby leading to its weak utilization. Factors like complexity, compatibility and trialability were not assessed extensively by KiwiCare and would have hindered TMVC adoption. TMVC was mainly assessed according to its relative advantage and to its cost effectiveness along with other facilitating and accelerating factors. This is essential but should be alongside technological and other influencing factors highlighted in the literature.

The influence of object-image velocity change on perceived heading in minimal environments

When human observers move forward and rotate their eyes, a complex pattern of light flows across the retina. This pattern is referred to as retinal flow. A model has been proposed to explain how humans perceive their direction of self-movement (or heading) from (1) static depth, (2) direction of image motion, and (3) whether image velocity undergoes acceleration or deceleration (Wang & Cutting, 1999). However, findings from past research in which sparse or minimalist stimuli were used have suggested that not all of the information to which participants are sensitive is captured within the scope of this model. In particular it has been suggested that the magnitude or size of image velocity change may be of significance beyond simply whether image velocity could be categorized as speeding up (i.e., accelerating) or slowing down (i.e., decelerating). In two experiments, the influence of this factor on heading judgments under minimal conditions was investigated. Evidence was found in support of the idea that the rate of image velocity change can influence judgments of the direction of self-movement in minimalist conditions.

Defining the Australian mechanical engineer

The attribute focus in engineering education now adopted by the engineering education accrediting bodies of the US, UK and Australia is based on meeting the assumed needs of professional practice. It is associated with an increasing expectation by employers of work-ready graduates rather than relying on subsequent work-based learning and experience to develop many of the essential professional practice attributes. Yet the scope of the mechanical engineering profession is broad and views of practitioners contributing to debate on attribute requirements are largely influenced by their own often unique professional formation.

In addition, the formative development of the profession in Australia has been significantly influenced by 19th and 20th century UK and US practices, although historically the industrial profile of Australia has been strikingly different. An analysis of current industry distribution of Australian, UK and US mechanical engineers presented in this paper shows continuing, although less marked, differences.

To develop a clearer perception of the profession in Australia, its educational formation, and operational environment, this paper provides a concise study of the formative development of the profession, and presents a breakdown of the industry sectors in which they are currently employed. The effects of momentous global changes in engineering employment and formation over recent decades are also discussed.

Recent changes in engineering employment have included major structural changes to organisations, accelerating technical and educational developments and mounting societal expectations making it imperative that attributes be attuned to the new engineering paradigm as increasing demands are placed on our graduates.

This paper provides an essential foundation for ongoing debate and analysis of attribute needs related to this broadly based engineering discipline. Although presented from an Australian perspective, many issues discussed are applicable worldwide.

A role for skeletal muscle stearoyl-CoA desaturase 1 in control of thermogenesis

An enhanced metabolic efficiency for accelerating the recovery of fat mass (or catch-up fat) is a characteristic feature of body weight regulation after weight loss or growth retardation and is the outcome of an "adipose-specific" suppression of thermogenesis, i.e., a feedback control system in which signals from the depleted adipose tissue fat stores exert a suppressive effect on thermogenesis. Using a previously described rat model of semistarvation-refeeding in which catch-up fat results from suppressed thermogenesis per se, we report here that the gene expression of stearoyl-coenzyme A desaturase 1 (SCD1) is elevated in skeletal muscle after 2 wk of semistarvation and remains elevated in parallel to the phase of suppressed thermogenesis favoring catch-up fat during refeeding. These elevations in the SCD1 transcript are skeletal muscle specific and are associated with elevations in microsomal ^9 desaturase enzyme activity, in the ^9 desaturation index, and in the relative content of SCD1-derived monounsaturates in several lipid fractions extracted from skeletal muscle. An elevated skeletal muscle SCD1, by desaturating the products of de novo lipogenesis and diverting them away from mitochondrial oxidation, would inhibit substrate cycling between de novo lipogenesis and lipid oxidation, thereby leading to a state of suppressed thermogenesis that regulates the body’s fat stores.—Mainieri, D., Summermatter, S., Seydoux, J., Montani, J. P., Rusconi, S., Russell, A. P., Boss, O., Buchala, A. J., Dulloo, A. G. A role for skeletal muscle stearoyl-CoA desaturase 1 in control of thermogenesis.

Thrifty metabolism that favors fat storage after caloric restriction: a role for skeletal muscle phosphatidylinositol-3-kinase activity and AMP-activated protein kinase

Energy conservation directed at accelerating body fat recovery (or catch-up fat) contributes to obesity relapse after slimming and to excess fat gain during catch-up growth after malnutrition. To investigate the mechanisms underlying such thrifty metabolism for catch-up fat, we tested whether during refeeding after caloric restriction rats exhibiting catch-up fat driven by suppressed thermogenesis have diminished skeletal muscle phosphatidylinositol-3-kinase (PI3K) activity or AMP-activated protein kinase (AMPK) signaling—two pathways required for hormone-induced thermogenesis in ex vivo muscle preparations. The results show that during isocaloric refeeding with a low-fat diet, at time points when body fat, circulating free fatty acids, and intramyocellular lipids in refed animals do not exceed those of controls, muscle insulin receptor substrate 1-associated PI3K activity (basal and in vivo insulin-stimulated) is lower than that in controls. Isocaloric refeeding with a high-fat diet, which exacerbates the suppression of thermogenesis, results in further reductions in muscle PI3K activity and in impaired AMPK phosphorylation (basal and in vivo leptin-stimulated). It is proposed that reduced skeletal muscle PI3K/AMPK signaling and suppressed thermogenesis are interdependent. Defective PI3K or AMPK signaling will reduce the rate of substrate cycling between de novo lipogenesis and lipid oxidation, leading to suppressed thermogenesis, which accelerates body fat recovery and furthermore sensitizes skeletal muscle to dietary fat-induced impairments in PI3K/AMPK signaling.—Summermatter, S., Mainieri, D., Russell, A. P., Seydoux, J., Montani, J. P., Buchala, A., Solinas, G., Dulloo, A. G. Thrifty metabolism that favors fat storage after caloric restriction: a role for skeletal muscle phosphatidylinositol-3-kinase activity and AMP-activated protein kinase.

Investor perception of the business case for sustainable office buildings : evidence from New Zealand

Over recent years the global market for sustainable commercial property has been growing in importance, with rapid growth occurring overseas that has led to substantial changes in the property markets. The New Zealand property industry has been recently introduced to the concept of sustainability, and although still at an early stage is already noticing the accelerating uptake of sustainability in the industry. Although certain measures have been taken by the New Zealand Green Building Council and government mandates, there remains still a common assumption that there is considerable hesitation and skeptism in the market from both an investor’s and a building owner’s perspective.

The research presented in this paper reports on the results of an investigation into the market perception toward sustainable buildings from the investment community in New Zealand. Property developers and investors from New Zealand were surveyed about their perception of sustainable buildings in New Zealand and their actions with regards to their own commercial portfolios, as well as the impact sustainability is having upon investment decisions. This paper presents the results of research conducted into the relationship between the elements of sustainability and the market value of an office building. The paper provides an insight into the rapidly evolving area of sustainability and office buildings, with the emphasis placed on the valuation process that seeks to assess a hypothetical purchaser’s perspective of this relationship.