Faster group operations on elliptic curves

This paper improves implementation techniques of Elliptic Curve Cryptography. We introduce new formulae and algorithms for the group law on Jacobi quartic, Jacobi intersection, Edwards, and Hessian curves. The proposed formulae and algorithms can save time in suitable point representations. To support our claims, a cost comparison is made with classic scalar multiplication algorithms using previous and current operation counts. Most notably, the best speeds are obtained from Jacobi quartic curves which provide the fastest timings for most scalar multiplication strategies benefiting from the proposed 12M + 5S + 1D point doubling and 7M + 3S + 1D point addition algorithms. Furthermore, the new addition algorithm provides an efficient way to protect against side channel attacks which are based on simple power analysis (SPA). Keywords: Efficient elliptic curve arithmetic,unified addition, side channel attack.

Principal preparation and training : a look at China and its issues

Purpose: The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number of countries. As an illustration, it provides an overview of the curriculum used in the initial preparation of school principals at Beijing Normal University.-----Design/methodology/approach: The paper draws mainly on writing and research from China, Australia and the USA to explore principal preparation and training in China.-----Findings: In addition to providing a rich description of principal preparation in China, the paper's main findings comprise seven key challenges that confront China as it endeavours to provide quality principal preparation. These challenges include China's diversity and uneven social, cultural and educational development; limited resources in some regions throughout China; the place and importance of study tours for principal preparation; the teaching approach used to train principals; the process used for assessing principal learning during their training programs; the limited transfer of learning from the classroom to the school environment; and the timing of training for principals.-----Practical implications: Each of the challenges arising here raises important practical implications for developers of principal training programs.-----Originality/value: The paper paints a picture of principal preparation in China and raises a number of issues and challenges with which it continues to grapple. Of note is that China is not alone in facing some of these ongoing concerns.

Body-shadowing effects in indoor MIMO-OFDM channel capacity

We investigate Multiple-Input and Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems behavior in indoor populated environments that have line-of-site (LoS) between transmitter and receiver arrays. The in-house built MIMO-OFDM packet transmission demonstrator, equipped with four transmitters and four receivers, has been utilized to perform channel measurements at 5.2 GHz. Measurements have been performed using 0 to 3 pedestrians with different antenna arrays (2 £ 2, 3 £ 3 and 4 £ 4). The maximum average capacity for the 2x2 deterministic Fixed SNR scenario is 8.5 dB compared to the 4x4 deterministic scenario that has a maximum average capacity of 16.2 dB, thus an increment of 8 dB in average capacity has been measured when the array size increases from 2x2 to 4x4. In addition a regular variation has been observed for Random scenarios compared to the deterministic scenarios. An incremental trend in average channel capacity for both deterministic and random pedestrian movements has been observed with increasing number of pedestrian and antennas. In deterministic scenarios, the variations in average channel capacity are more noticeable than for the random scenarios due to a more prolonged and controlled body-shadowing effect. Moreover due to the frequent Los blocking and fixed transmission power a slight decrement have been observed in the spread between the maximum and minimum capacity with random fixed Tx power scenario.

How to extract and expand randomness : a summary and explanation of existing results

We examine the use of randomness extraction and expansion in key agreement (KA) pro- tocols to generate uniformly random keys in the standard model. Although existing works provide the basic theorems necessary, they lack details or examples of appropriate cryptographic primitives and/or parameter sizes. This has lead to the large amount of min-entropy needed in the (non-uniform) shared secret being overlooked in proposals and efficiency comparisons of KA protocols. We therefore summa- rize existing work in the area and examine the security levels achieved with the use of various extractors and expanders for particular parameter sizes. The tables presented herein show that the shared secret needs a min-entropy of at least 292 bits (and even more with more realistic assumptions) to achieve an overall security level of 80 bits using the extractors and expanders we consider. The tables may be used to �nd the min-entropy required for various security levels and assumptions. We also �nd that when using the short exponent theorems of Gennaro et al., the short exponents may need to be much longer than they suggested.

Application of system dynamics for evaluating truck load regulations in Anhui, China

In the critical situation of prevailing overweight transportation and crag-fast enforcement in Chinese highway networks, this paper develops a methodological framework for truck weight regulation (TWR) evaluation using System Dynamics (SD). Composed of five interrelated subsystems, the framework is able to capture the highway, vehicle and freight variables that influence the effect of TWR and transportation efficiency over time. It specifically describes the development and use of the Truck Weight Regulation Evaluating Model (TWREM) for the highway freight system in Anhui province, China. Three policy alternatives are analyzed: 1) tolerant policy approach, which allows heavy-duty freight activity to continue in its current state, and is shown to lead to nearly catastrophic results; 2) rigid policy approach, which would terminate all heavy-duty freight activities immediately, and is shown to be economically infeasible; and 3) moderate policy approach, which advocates a gradual reduction of heavy-duty freight activities to a moderate state. The simulation results shows that the moderate policy approach is the most appropriate option to solve the social and economic problems arising from the activities of the heavy-duty freight transportation in Anhui. In addition, some suggestions of TWR policy in China are also made in this paper.

The role of product involvement in e-service evaluations

This paper provides conceptual and empirical insights into consumers’ evaluations of online services and their consequent behavioural intentions. We show that behavioural intentions in online contexts are driven primarily by two factors, namely online service satisfaction and perceived service quality. Perceived sacrifice and service quality are found to have an indirect effect on online service satisfaction through their influences on perceived value associated with the online service. In addition, we examine the moderating effects of product involvement and discuss the implications of our research findings.

What’s in a handshake? Exploring business-to-business relational exchange

Despite its importance in the development of competitive advantage, attempts to unify diverse classifications of business-to-business relational exchange have been largely unsuccessful. We used 18 semi-structured, in-depth interviews with managers from a wide range of industries to explain the business-to-business relational exchange construct. Analysis of the data revealed that business-to-business relational exchange comprises five key dimensions. These are communication, compatibility, commitment, trust and power symmetry. The research highlights the importance of personal interaction in business relationships and provided additional insights into the importance of affective commitment. In addition we reveal a number of negative consequences of affective commitment, which have been previously unexplored. A new conceptual model of business-to-business relational exchange is presented, which synthesises these findings and directs future research.

Union strategies in representing ‘new’ workers : the comparative case of UK and Australian retail unions

This paper is a comparative exploratory study of the changing nature of employee voice through trade union representation in the retail industry in the UK and Australia. In both countries, the retail industry is a major employer and is one of the few private sector service industries with significant union membership (Griffin et al 2003). The relevant unions, the Distributive and Allied Workers Union (USDAW) and the Shop, Distributive and Allied Union (SDA), are the fourth largest and largest unions in the UK and Australia respectively. However, despite this seeming numerical strength in membership, the characteristics of the industry provide unique challenges for employee voice and representation. The significance of the study is that any extension of representation and organisation by unions in the retail sector is valuable socially and politically, given that retail workers are often categorised a s vulnerable, due to their low pay, the predominance of disadvantaged labour market groups such a s women and young people, workers’ atypical employment arrangements and, in the case of the UK, variable levels of union recognition which inhibit representation (Broadbridge 2002; Henley 2006; Lynch 2005; Roan & Diamond 2003; Reynolds et al 2005). In addition, specifically comparative projects have value in that they allow some variables relating to the ‘industry’ to be held constant, thus reducing the range of potential explanations of differences in union strategy. They also have value in that the research partners may be more likely to notice and problematise taken-for-granted aspects of practices in another country, thus bringing to the fore key features and potentially leading to theoretical innovation. Finally, such projects may assist in transnational diffusion of union strategy.

Construction safety in the repair and maintenance sector

Statistics indicate that the percentage of fatal industrial accidents arising from repair, maintenance, minor alteration and addition (RMAA) works in Hong Kong was disturbingly high and was over 56% in 2006. This paper provides an initial report of a research project funded by the Research Grants Council (RGC) of the HKSAR to address this safety issue. The aim of this study is to scrutinize the causal relationship between safety climate and safety performance in the RMAA sector. It aims to evaluate the safety climate in the RMAA sector; examine its impacts on safety performance, and recommend measures to improve safety performance in the RMAA sector. This paper firstly reports on the statistics of construction accidents arising from RMAA works. Qualitative and quantitative research methods applied in conducting the research are dis-cussed. The study will critically review these related problems and provide recommendations for improving safety performance in the RMAA sector.

Cyclic strain disrupts endothelial network formation on Matrigel

Most forms of tissue healing depend critically on revascularisation. In soft tissues and in vitro, mechanical stimuli have been shown to promote vessel-forming activity. However, in bone defects, increased interfragmentary motion impairs vascular regeneration. Because these effects seem contradictory, we aimed to determine whether a range of mechanical stimuli exists in which angiogenesis is favoured. A series of cyclic strain magnitudes were applied to a Matrigel-based “tube formation” assay and the total lengths of networks formed by human microvascular endothelial cells measured at 24 h. Network lengths were reduced at all strain levels, compared to unstretched controls. However, the levels of pro-angiogenic matrix metalloproteases-2 and -9 in the corresponding conditioned media were unchanged by strain, and vascular endothelial growth factor was uniformly elevated in stretched conditions. By repeating the assay with the addition of conditioned media from mesenchymal stem cells cultivated in similar conditions, paracrine stimuli were shown to increase network lengths, but not to alter the negative effect of cyclic stretching. Together, these results demonstrate that directly applied periodic strains can inhibit endothelial organisation in vitro, and suggest that this may be due to physical disruption rather than biochemical modulation. Most importantly, the results indicate that the straining of endothelial cells and their assembly into vascular-like structures must be studied simultaneously to adequately characterise the mechanical influence on vessel formation.

Decision-making style and self-concept

The Flinders Decision-Making Questionnaire (FDMQ) (Mann, 1982), which measures three decision-making styles and decision-making self-esteem, and the Self-Description Questionnaire III (SDQ HI) (Marsh & O'Neill, 1984), which measures 13 facets of self-concept; were administered to 475 university students to investigate some of the tenets of Janis and Mann's (1976, 1977) conflict model of decision-making and to further investigate the influence of self-concept on decision-making behaviours. The findings empirically validated Janis and Mann's (1977) link between decision-making self-esteem and decision-making style. Modest relationships, in the predicted direction, were found between decision-making self-esteem and the three decision-making styles (Vigilance, Defensive Avoidance, and Hypervigilance). In addition, specific facets of self-concept (General, Verbal, Academic, Honesty/Reliability and Problem-Solving Self Concepts) were related to self-reported decision-making behaviours.

The inclusion of first aid in an injury prevention curriculum

Prompt first aid can have considerable benefits. The Skills for Preventing Injury in Youth (SPIY) program aims to teach, in part, first aid skills along with additional injury prevention strategies. The approach to including first aid is both as an injury prevention strategy and a way in which to reduce the severity of injuries once they occur. This paper outlines an implementation trial of the SPIY program with particular emphasis on the delivery and implementation of first aid skills. SPIY demonstrated effectiveness with regard to first aid knowledge and as an injury prevention program. SPIY is taught in the Year 9 Health curriculum by HPE teachers. Students and teachers who undergo or deliver such training offer important perspectives about implementation. In addition independent observation of delivery provides further information about the program. The research aimed to examine teachers‟ and students‟ experiences of first aid activities within a school-based injury prevention and control program and identify key issues in delivery from independent observation of the program. Focus groups were held with 8 teachers who delivered, and 70 students who participated in the SPIY curriculum program. Results showed favourable reports on the delivery of first aid material however teachers noted challenges in delivering practical activities. In sum, first aid can be effectively implemented within the high school setting and both students and teachers identified multiple benefits and positive experiences after undertaking first aid training.

Modelling urban public transit users' route choice behaviour: review and outlook

This paper reviews the main development of approaches to modelling urban public transit users’ route choice behaviour from 1960s to the present. The approaches reviewed include the early heuristic studies on finding the least cost transit route and all-or-nothing transit assignment, the bus common line problem and corresponding network representation methods, the disaggregate discrete choice models which are based on random utility maximization assumptions, the deterministic use equilibrium and stochastic user equilibrium transit assignment models, and the recent dynamic transit assignment models using either frequency or schedule based network formulation. In addition to reviewing past outcomes, this paper also gives an outlook into the possible future directions of modelling transit users’ route choice behaviour. Based on the comparison with the development of models for motorists’ route choice and traffic assignment problems in an urban road area, this paper points out that it is rewarding for transit route choice research to draw inspiration from the intellectual outcomes out of the road area. Particularly, in light of the recent advancement of modelling motorists’ complex road route choice behaviour, this paper advocates that the modelling practice of transit users’ route choice should further explore the complexities of the problem.

The reputation of the corporate social responsibility industry in Australia

Corporate social responsibility (CSR) is increasingly seen as an imperative for sustainable business and there is a growing literature on the effect of CSR on corporate reputation. Despite this, a pall of ambiguity and uncertainty remains around what CSR means and how it should be practiced. This paper offers a unique addition to the body of literature to date by revealing that CSR is an emerging industry in Australia, which is in the process of developing its own reputation as a set of business practices. The paper is based on exploratory qualitative research using a case study methodology. Interviews were conducted with key actors within the industry to investigate shared understandings of what CSR means, perceptions of CSR practice and of the industry as a whole, and who is involved in shaping these perceptions. The research revealed that the CSR industry in Australia is in its early stages of development and is therefore in need of increased internal cooperation if it is to develop a strong reputation.

The Google online marketing challenge and research opportunities

The Google Online Marketing Challenge is an ongoing collaboration between Google and academics, to give students experiential learning. The Challenge gives student teams US$200 in AdWords, Google’s flagship advertising product, to develop online marketing campaigns for actual businesses. The end result is an engaging in-class exercise that provides students and professors with an exciting and pedagogically rigorous competition. Results from surveys at the end of the Challenge reveal positive appraisals from the three—students, businesses, and professors—main constituents; general agreement between students and instructors regarding learning outcomes; and a few points of difference between students and instructors. In addition to describing the Challenge and its outcomes, this article reviews the postparticipation questionnaires and subsequent datasets. The questionnaires and results are publicly available, and this article invites educators to mine the datasets, share their results, and offer suggestions for future iterations of the Challenge.