Compensatory Ability to Null Mutation in Metabolic Networks

Robustness is an inherent property of biological system. It is still a limited understanding of how it is accomplished at the cellular or molecular level. To this end, this article analyzes the impact degree of each reaction to others, which is defined as the number of cascading failures of following and/or forward reactions when an initial reaction is deleted. By analyzing more than 800 organism’s metabolic networks, it suggests that the reactions with larger impact degrees are likely essential and the universal reactions should also be essential. Alternative metabolic pathways compensate null mutations, which represents that average impact degrees for all organisms are small. Interestingly, average impact degrees of archaea organisms are smaller than other two categories of organisms, eukayote and bacteria, indicating that archaea organisms have strong robustness to resist the various perturbations during the evolution process. The results show that scale-free feature and reaction reversibility contribute to the robustness in metabolic networks. The optimal growth temperature of organism also relates the robust structure of metabolic network.

The underpricing of A-REIT IPOs in Australia during 2002 to 2008

This study analyses 45 Australian Real Estate Investment Trust (A-REIT) initial public offerings (IPOs) in Australia from January 2002 to June 2008, since the introduction of the single responsible entity to oversee the activities of listed property trusts (LPTs) Rather than the trustee and manager roles. The study finds that this sample of A-REIT IPOs had a significant 3.37% underpricing and that the direct costs of capital raising help explain this indirect cost of underpricing. There is some evidence to suggest that A-REIT IPOs that seek to raise more equity capital have less underpricing, while those that are subscribed to more quickly have higher underpricing. The findings offer insights for issuers who seek to maximize the value of the A-REIT at the time of the IPO, underwriters who guarantee the success of the capital raising and for investors who are looking to invest in Australian A-RE1T 1POs.

Managing data using neighbour replication on a triangular-grid structure

Data in grid research deals with storage, replication, and management of large data sets in a distributed environment. The all-data-to-all-sites replication schemes, like Read-One Write-All (ROWA) and Tree Grid Structure (TGS), are the popular techniques in grid. However, these techniques have a weakness in data storage capacity and data access times. In this paper, we propose the all-data-to-some-sites scheme called the 'Neighbour Replication on Triangular Grid' (NRTG) technique. The proposed scheme minimises the storage capacity as well as data access time with high update availability. It also tolerates failures such as server and site failures.

Multi-criteria content adaptation service selection broker

In this paper, we propose a service-oriented content adaptation framework and an approach to the Content Adaptation Service Selection (CASS) problem. In particular, the problem is how to assign adaptation tasks (e.g., transcoding, video summarization, etc) together with respective content segments to appropriate adaptation services. Current systems tend to be mostly centralized suffering from single point failures. The proposed algorithm consists of a greedy and single objective assignment function that is constructed on top of an adaptation path tree. The performance of the proposed service selection framework is studied in terms of efficiency of service selection execution under various conditions. The results indicate that the proposed policy performs substantially better than the baseline approach.

Using constructed-response and multiple-choice questions in undergraduate examinations

This paper looks at the use of constructed-response and multiple-choice questions in first year management examinations involving 2364 students over a three semester period in 2008-9. It also compares student’s performance in research and analytical assignments with their results in Multiple-Choice tests. The results show that students who perform poorly in non-multiple-choice tests are slightly advantaged by multiple-choice tests. However, students who display high distinction scores in other pieces of assessment do not receive any advantage from multiple-choice testing. Interestingly, the research also highlighted that female students perform better in their articulation of management techniques overall, but do not gain the same comparative advantage from multiple choice testing. The analysis of the assessment methods was extremely useful in predicting the level of failures for the unit in the subsequent year. Finding the right balance of assessment tasks in first year university business courses is extremely difficult, using multiple-choice tests can be useful tool as part of the assessment mix in management units.

Minimum reconfiguration for fault tolerant manipulators

When a robotic manipulator is fault tolerant it is beneficial to study the configurations which tolerate non-catastrophic locked joint failures with a minimum relative change for the joint velocities. This problem is addressed using the properties of the condition number of the Jacobian matrix. The relationship between the faults within the joints of the manipulators and the condition number of the Jacobean matrix is used to introduce the optimal configurations for fault recovery. These optimum configurations require a minimum reconfiguration for fault tolerance of robotics manipulators. Then these configurations are studied for a 4-DOF planar manipulator to validate the proposed framework.

Underpricing, risk management, hot issue and crowding out effects : evidence from the Australian resources sector initial public offerings

The main purpose of this paper is to explore the role of risk management, speculative industry competition effect and hot issue markets. We used a sample of 260 initial public offerings (IPOs) in the Australian resource sector for the 1994–2004 period to test the underpricing effect. We do not find any evidence that risk management can reduce the uncertainty relating to the new issue and hence alleviate the extent of underpricing. A plausible explanation for this lack of evidence is the poor information content of publicly available disclosures regarding risk management activities of IPO firms. We further provide evidence that the underpricing returns for resources IPOs are not impacted upon by the strength of alternative speculative IPO markets. We also show that the degree of underpricing adjusts to both market return in the preceding three months and the average underpricing of resources IPOs in the 12 month period leading to the float which offers an explanation to the hot issue effect observed in the IPO market.

On the effort of task completion for partially-failed manipulators

Adding to a previous work of the authors for task completion for partially failed manipulator, other aspects of the effort are discussed. The paper aims to investigate on the strategies of maximum effort for maintaining the availability of partially failed manipulators. The failures are assumed as the joint lock failures of the manipulators. The main objective is to facilitate the existing manipulators to continue their tasks even if a non catastrophic fault occurs into their joints. The tasks includes motion tasks and force tasks. For each group of tasks a constrained optimality problem is introduced. Then in a case study a required force profile on a desired trajectory using a 3DOF planar manipulator is indicated. Through this study the joint angles and joint torques for a healthy manipulator and a faulty manipulator are shown. It is illustrated that a failure in the second joint is tolerated on the trajectory of end-effector.

About global leadership and global ethics, and a possible moral compass : an introduction to the special issue

This paper reviews a number of huge challenges to ethical leadership in the twenty-first century and concludes that the need for global ethical leadership is not merely a desirable option, but rather – and quite literally – a matter of survival. The crises of the recent past reveal huge, and in some cases criminal, failures of both ethics and leadership in finance, business and government. We posit that mainstream economic theory’s construct of ‘homo economicus’ and its faith in the ‘invisible hand’ of the market constitute deeply flawed foundations upon which alone policy may be built and, farthermore, that these problematic foundations exert substantial shaping power over the institutional and discursive landscapes in which international business is transacted. Analogously, we argue that dominant approaches to business ethics and corporate social responsibility are, if not incorrect, at least in need of revisiting in terms of questioning their basic assumptions. Instead of the smugness of Western (especially Anglo-American) attitudes towards other ways of thinking, valuing and organising, it appears clear that openness, cooperation and co-creation between the developed and developing worlds is a basic prerequisite for dealing with the global challenges facing not just leaders, but humanity as a whole. This objective of stimulating discussion between dominant and marginal voices has guided our selection of papers for this Special Issue. We have thus included not only representatives of research from within the parameters of mainstream business ethics, IB or leadership scholarship, but also innovative contributions from fields such as military history, information technology, regulation, spirituality and sociology.

UN-consistent : a comparison of Australia's military interventions in Somalia and Rwanda

This article seeks to compare Australia's involvement in two key 1990s peace missions: those to Somalia in 1992-93 and Rwanda in 1994-95. While there are many similarities between the two missions in terms of time, scale and theatre, the differences are more important. Both missions are usually recalled as failures despite the Australian troops having been extremely successful in their roles during both deployments. Moreover the experiences with intervention in Africa seem to have forever blighted Australian participation in peace missions on that continent.

Towards the development of a construction supply chain transaction cost economic model for strategic infrastructure procurement evaluation

Australia has adopted public-private partnership (PPP) as a major strategy for procuring infrastructure for decades. However, even though considered to be a mature and sophisticated market, several major
failures have occurred resulting in increasing financial burdens on taxpayers. Failures have typically been traced back to economic evaluation and, in particular, value-for-money across the supply chain
in the original proposal. However, the literature review identified that there was no economic model that evaluated holistically the transaction costs of PPPs across the supply chain. In this paper, theories of transaction cost economics and construction supply chain economics are critiqued and analysed in order to develop a strategic infrastructure procurement evaluation model. The model will offer decision makers with an insight into project life cycle economic outcomes needed to successfully deliver PPPs.

Re-thinking Middle Eastern democracy : lessons from ancient Mesopotamia

The issue of Middle Eastern democracy has long inspired lively academic debate and research from across the ideological and political spectrum. Despite their differences, much of this work measures the successes and failures of Middle Eastern democracy against the Western model, with its antecedents in the political machinations found in Athens during the 5th century B.C. However, there is growing evidence to suggest that the history of democracy began on the other side of the Occidental/Oriental line and can be traced as far back as the early Mesopotamian myths of Enuma Elish, through to the grand empires of the Babylonians, Assyrians, Egyptians and Phoenicians. In the interest of fostering a liberal, democratic and egalitarian Middle East, this paper concludes by suggesting that one strategy for re-thinking the Middle East’s democratisation is to engage the powerful discourses of the Middle East’s ancient, and democratic, past.

Ten years of environmental university building

The authors have been involved in over ten years of environmental consulting and research on university buildings. Numerous simulations and measurement studies have occurred over this period of time. The intentions have always been to improve and optimise the environmental performing aspects of a building. This paper is a reporting of the implemented strategies, their pre-building research investigation as well as their operational outcomes. Their successes and failures are discussed here. This research is intended as a feedback loop to future design specification, commissioning and maintenance improvements. In hindsight many of the environmental concepts, when executed as planned, were successful. However, often those requiring extensive control, such as lighting, ventilation and mechanical air-conditioning were a failure. The observations between simulation and actual performance are also noted. The paper includes discussion about some of the obstacles in building procurement which can hinder the result of a good environmental performing building.

Fault-tolerant scheduling with dynamic number of replicas in heterogeneous systems

In the existing studies on fault-tolerant scheduling, the active replication schema makes use of ε + 1 replicas for each task to tolerate ε failures. However, in this paper, we show that it does not always lead to a higher reliability with more replicas. Besides, the more replicas implies more resource consumption and higher economic cost. To address this problem, with the target to satisfy the user’s reliability requirement with minimum resources, this paper proposes a new fault tolerant scheduling algorithm: MaxRe. In the algorithm, we incorporate the reliability analysis into the active replication schema and the theoretical analysis and experiments prove that the MaxRe algorithm’s schedule can certainly satisfy user’s reliability requirements. And the MaxRe scheduling algorithm can achieve the corresponding reliability with at most 70% fewer resources than the FTSA algorithm.

Investigating directionality for a media consumption construct : establishing the utility of confirmatory vanishing tetrad analysis

Purpose – When assessing the psychometric properties of measures and estimate relations among latent variables, many studies in the social sciences (including management and marketing) often fail to comprehensively appraise the directionality of indicants. Such failures can lead to model misspecification and inaccurate parameter estimates. The purpose of this paper is to apply a post hoc test called confirmatory vanishing tetrad analysis (CTA hereafter) to a single construct called mass media consumption information exposure, which antecedent studies conceptually posited to be a formative (causative) representation.
Design/methodology/approach – This paper analyses a consumer sample of 585 US respondents and applies the CTA test to a single construct by its inclusion in various matrices within a statistical analysis system-macro that takes into account nonnormal data characteristics. The matrices are derived from Mplus 5 through the estimation of a single-factor congeneric model. The CTA test calculates a test statistic similar to an asymptotic x2 distribution with degrees of freedom equal to the number of nonredundant tetrads tested.
Findings – The preliminary data analyses reveal that the data characteristics are nonnormal which is not uncommon in social research. The CTA results reveal that the reflective (emergent) item orientation cannot be fully ruled out as being the correct model representation. This is in contrast to prior theoretical conceptual work which would strongly support this construct being a formative representation.
Originality/value – Insofar as the authors are aware, there is no paper with a particular focus on how the CTA might not provide sound results with a demonstrated example. The paper makes a valuable contribution by discussing modelling philosophy and a procedure for directionality testing. The authors advocate the implementation of pre and post hoc tests as a key component of standard research practice.