Reducing position error of cantilevered loads in motion systems

The positioning error of a large cantilevered mass that is actuated at its supported end is minimized as this mass travels at challenging high speeds and accelerations. An integrated approach is adopted to realize the task. After selecting the appropriate actuator that would provide higher rigidity, the system is viewed as a multi-degree of freedom system, and hence the concept of system-generated disturbance is introduced. This allows the use of appropriate mechanical design considerations and a proper generation of the kinematics commands to minimize such disturbance. A disturbance observer is then designed to detect and compensate the remaining disturbance, hence minimizing the positioning error.
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A search for sources of preferential attachment phenomena in e-business

This paper presents and empirical study in which we examine the process of preserential attachment as it applies to business enterprises on the World Wide Web.  Using randomly selected business Web pages as nodes and their inbound links as edges, we explre the role of parked domain names in link creation and preferential attachment at very granular levels.  Our research leads us to the conclusion that the abundance of parked domain name sites does not present a plausible explanation for preferential attachment.

Expanding the realm of best practices in cooperative industry-based learning in information systems and information technology : an inter-institutional investigation in Australian higher education

The professional fields of information systems and information technology are drivers and enablers of the global economy. Moreover, their theoretical scope and practices are global in focus. University graduates need to develop a range of leadership, conceptual and technical capacities to work effectively in, and contribute to, the shaping of companies, business models and systems which operate in globalised settings. This paper reports a study of the operation of industry‐based learning (IBL) at three Australian universities, which employ different models and approaches, as part of a series of investigations of the needs, circumstances and perspectives of various stakeholders (program coordinator, faculty teaching staff, the students, industry mentors, and the professional body). The focus of this paper is a discussion of salient pragmatic considerations in an attempt to conceptualize what constitutes best practice in offering industry‐based learning for higher education students in the disciplines of information systems and information technology (Asia‐Pacific Journal of Cooperative Education, 9(2), 73‐80).

Power control in CDMA systems based on channel identification

Power control design is a critical aspect of CDMA cellular systems design. This paper develops an adaptive power controller design method for CDMA systems. The key to the power control design is on the recursive identification of the underlying wireless stochastic channel model parameters. The identification process guarantees the power controller to work well for systems in unknown or time varying network environment.

There's SEM and 'SEM' : a critique of the use of PLS regression in information systems research

In disciplines other than IS, the use of covariance-based structural equation modelling (SEM) is the mainstream method for SEM analysis, and for confirmatory factor analysis (CFA). Yet a body of IS literature has developed arguing that PLS regression is a superior tool for these analyses, and for establishing reliability and validity. Despite these claims, the views underlying this PLS literature are not universally shared. In this paper the authors review the PLS and mainstream SEM literatures, and describe the key differences between the two classes of tools. The paper also canvasses why PLS regression is rarely used in management, marketing, organizational behaviour, and that branch of psychology concerned with good measurement – psychometrics. The paper offers some practical options to Australasian researchers seeking greater mastery of SEM, and also acts as a roadmap for readers who want to check for themselves what the mainstream SEM literature has to say.

Transparent and autonomic rollback-recovery in cluster systems

Cluster systems provide an excellent environment to run computation hungry applications. However, due to being created using commodity components they are prone to failures. To overcome these failures we propose to use rollback-recovery, which consists of the checkpointing and recovery facilities. Checkpointing facilities have been the focus of many previous studies; however, the recovery facilities have been overlooked. This paper focuses on the requirements, concept and architecture of recovery facilities. The synthesized fault tolerant system was implemented in the GENESIS system and evaluated. The results show that the synthesized system is efficient and scalable.

The curious case of the missing employee in information systems research

ICT has transformed our working lives. The IS discipline has a great deal to contribute to better understand the employee management issues associated with the implementation of new technologies. This paper analyses the IS literature to ascertain the level of research being undertaken in the area of employee management and human resource management. The analysis illustrates that employee management is currently not a key area of research in the mainstream IS discipline. The antecedents as to why there have not been many papers published in this area are many and as yet unstudied. The paper concludes by suggesting future areas of research addressing employee management issues.

Dielectrophoresis for manipulation of micro/nano particles in microfluidic systems

Dielectrophoretic (DEP) force is exerted when a neutral particle is polarized in a non-uniform electric field, and depends on the dielectric properties of the particle and the suspending medium. The integration of DEP and microfluidic systems offers numerous applications for the separation, trapping, assembling, transportation, and characterization of micro/nano particles. This article reviews the applications of DEP forces in microfluidic systems. It presents the theory of dielectrophoresis, different configurations, and the applications of such systems for particle manipulation and device fabrication.

Applications of aptamers in nanodelivery systems in cancer, eye and inflammatory diseases

Aptamers are an interesting class of molecules that have potential in many facets of human health. They are characterized by high affinity and specificity to their targets, are small in size, have similar properties to antibodies, but are made synthetically. All of these properties, among others, give aptamers the potential to diagnose, image and treat like no other molecules. By combining the unique properties of aptamers with the ever expanding field of nanotechnology and all it has to offer, we are entering a very promising new area of targeted nanodelivery treatments. These treatments have found success in the complex disease processes of cancer, eye and inflammatory diseases.

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.

The role of herbivorous water birds in aquatic systems through interactions with aquatic macrophytes, with special reference to the Bewick’s Swan – Fennel Pondweed system

The role of aquatic macrophytes in stimulating biodiversity and maintaining clear waters is currently undisputed. The management of (eutrophic) shallow waters is therefore often directed at (re-)establishing macrophyte domination. In contrast, the role of water birds has long been considered of minor importance for the functioning of fresh water ecosystems. Indeed, in terms of biomass and production, water birds constitute only a minor part of these systems. However, water birds may graze heavily on water plants under certain circumstances, and the question arises whether herbivorous water birds have an important indirect effect on shallow fresh water systems. Mainly illustrated with the interaction between Bewick’s Swans and Fennel Pondweed, we present data on the role that water plants may play in the life of water birds and how water birds may impact water plants’ fitness in terms of survival, production, dispersal and competitive ability. It appears that water plants may be crucial for water birds during periods of high-energy requirements, such as migration. Despite the plants’ costs associated with water bird grazing, the interaction between water birds and water plants varies in nature from an apparent predator–prey relationship to a mutually beneficial interaction depending on the context and the perspective. For the case of the Bewick’s Swan–Fennel Pondweed interaction, regular bird grazing is sustainable and may actually favour the plant’s dispersal. Thus, Bewick’s Swans themselves may in fact play a crucial role in establishing and maintaining the Fennel Pondweed rich staging sites between the swans’ wintering and breeding grounds, which are vital for the swans’ successful migration.

Identifying capabilities for the IT function to create agility in information systems

In this paper, we identify the necessary capabilities of the IT function to create agility in existing information systems. Agility is the ability to quickly sense and respond to environment perturbations. We contrast the agility perspective from a widely used industry framework with research perspectives on agility in the IS literature. We suggest Beer’s Viable System Model (VSM) is a useful meta-level theory to house agility elements from IS research literature, and apply VSM principles to identify the capabilities required of the IT function. Indeed, by means of a survey of 34 organisations, we confirm that the meta-level theory better correlates with reported agility measures than existing practice measures do on their own. From a research perspective, the incorporation of the VSM mechanism helps to explain ‘why’ the IT function is capable of creating agility. From a practical perspective of ‘how’, the findings point to a new set of capabilities of the IT function for future versions of the industry frameworks to enable agility.

Agility in information systems : enabling capabilities for the IT function

This research identifies how the IT function can create agility in existing information systems. Agility is the capability to quickly sense and respond to environmental perturbations. We contrasted perspectives on agility from a widely used industry framework and that of the IS research literature. Beer’s Viable System Model was a useful meta-level theory to house agility elements from IS research and it introduced cybernetic principles to identify the processes required of the IT function. Indeed, our surveys of 70 organizations confirmed that the applied theory better correlates with reported agility than does existing industry best practice.

The research conducted two quantitative surveys to test the applied theory. The first survey mailed a Likert-type questionnaire to the clients of an Australian IT consultancy. The second survey invited international members of professional interest groups to complete a web-based questionnaire. The responses from the surveys were analyzed using partial-least-squares modeling. The data analysis positively correlated the maturity of IT function processes prescribed by the VSM and the likelihood of agility in existing information systems. We claim our findings generalize to other large organizations in OECD member countries.

The research offers an agility-capability model of the IT function to explain and predict agility in existing information systems. A further contribution is to improve industry ‘best practice’ frameworks by prescribing processes of the IT function to develop in maturity.

Simulating crowd phenomena in African markets

Crowd simulation is an important feature in the computer graphics field. Typical implementations simulate battle scenes, emergency situations, safety issues or add content to virtual environments. The problem stated in this paper falls in the last category. We present a crowd simulation behavioural model which allows us to simulate identified phenomena in popular local African markets such as narrow street flows and crowd formation around street performances. We propose a three-tier architecture model enable to produce intentions, perform path planning and control movement. We demonstrate that this approach produces the desired behaviour associated with crowds in an African market, which includes navigation, flow formation and circle creation.