An Adaptive Genetic Algorithm with Dynamic Population Size for Optimizing Join Queries

The problem of finding the optimal join ordering executing a query to a relational database management system is a combinatorial optimization problem, which makes deterministic exhaustive solution search unacceptable for queries with a great number of joined relations. In this work an adaptive genetic algorithm with dynamic population size is proposed for optimizing large join queries. The performance of the algorithm is compared with that of several classical non-deterministic optimization algorithms. Experiments have been performed optimizing several random queries against a randomly generated data dictionary. The proposed adaptive genetic algorithm with probabilistic selection operator outperforms in a number of test runs the canonical genetic algorithm with Elitist selection as well as two common random search strategies and proves to be a viable alternative to existing non-deterministic optimization approaches.

Building theory at the intersection of ecological sustainability and strategic management

This article builds theory at the intersection of ecological sustainability and strategic management literature—specifically, in relation to dynamic capabilities literature. By combining industrial organization economics–based, resource-based, and dynamic capability–based views, it is possible to develop a better understanding of the strategies that businesses may follow, depending on their managers’ assumptions about ecological sustainability. To develop innovative strategies for ecological sustainability, the dynamic capabilities framework needs to be extended. In particular, the sensing–seizing–maintaining competitiveness framework should operate not only within the boundaries of a business ecosystem but in relation to global biophysical ecosystems; in addition, two more dynamic capabilities should be added, namely, remapping and reaping. This framework can explicate core managerial beliefs about ecological sustainability. Finally, this approach offers opportunities for managers and academics to identify, categorize, and exploit business strategies for ecological sustainability.

Facilitating intuitive-guided learning in a serious game through integration with a learning content management system

Increased global uptake of entertainment gaming has the potential to lead to high expectations of engagement and interactivity from users of technology-enhanced learning environments. Blended approaches to implementing game-based learning as part of distance or technology-enhanced education have led to demonstrations of the benefits they might bring, allowing learners to interact with immersive technologies as part of a broader, structured learning experience. In this article, we explore how the integration of a serious game can be extended to a learning content management system (LCMS) to support a blended and holistic approach, described as an 'intuitive-guided' method. Through a case study within the EU-Funded Adaptive Learning via Intuitive/Interactive, Collaborative and Emotional Systems (ALICE) project, a technical integration of a gaming engine with a proprietary LCMS is demonstrated, building upon earlier work and demonstrating how this approach might be realized. In particular, how this method can support an intuitive-guided approach to learning is considered, whereby the learner is given the potential to explore a non-linear environment whilst scaffolding and blending provide guidance ensuring targeted learning objectives are met. Through an evaluation of the developed prototype with 32 students aged 14-16 across two Italian schools, a varied response from learners is observed, coupled with a positive reception from tutors. The study demonstrates that challenges remain in providing high-fidelity content in a classroom environment, particularly as an increasing gap in technology availability between leisure and school times emerges.

Self-organising zooms for decentralised redundancy management in visual sensor networks

When visual sensor networks are composed of cameras which can adjust the zoom factor of their own lens, one must determine the optimal zoom levels for the cameras, for a given task. This gives rise to an important trade-off between the overlap of the different cameras’ fields of view, providing redundancy, and image quality. In an object tracking task, having multiple cameras observe the same area allows for quicker recovery, when a camera fails. In contrast having narrow zooms allow for a higher pixel count on regions of interest, leading to increased tracking confidence. In this paper we propose an approach for the self-organisation of redundancy in a distributed visual sensor network, based on decentralised multi-objective online learning using only local information to approximate the global state. We explore the impact of different zoom levels on these trade-offs, when tasking omnidirectional cameras, having perfect 360-degree view, with keeping track of a varying number of moving objects. We further show how employing decentralised reinforcement learning enables zoom configurations to be achieved dynamically at runtime according to an operator’s preference for maximising either the proportion of objects tracked, confidence associated with tracking, or redundancy in expectation of camera failure. We show that explicitly taking account of the level of overlap, even based only on local knowledge, improves resilience when cameras fail. Our results illustrate the trade-off between maintaining high confidence and object coverage, and maintaining redundancy, in anticipation of future failure. Our approach provides a fully tunable decentralised method for the self-organisation of redundancy in a changing environment, according to an operator’s preferences.

Performance evaluation of adaptive context aware rate selection algorithm (ACARS) for road safety applications in vehicular network

One of the major drawbacks for mobile nodes in wireless networks is power management. Our goal is to evaluate the performance power control scheme to be used to reduce network congestion, improve quality of service and collision avoidance in vehicular network and road safety application. Some of the importance of power control (PC) are improving spatial reuse, and increasing network capacity in mobile wireless communications. In this simulation we have evaluated the performance of existing rate algorithms compared with context Aware Rate selection algorithm (ACARS) and also seen the performance of ACARS and how it can be applied to road safety, improve network control and power management. Result shows that ACARS is able to minimize the total transmit power in the presence of propagation processes and mobility of vehicles, by adapting to the fast varying channels conditions with the Path loss exponent values that was used for that environment which is shown in the network simulation parameter. Our results have shown that ACARS is a very robust algorithm which performs very well with the effect of propagation processes that is prone to every transmitted signal in mobile networks. © 2013 IEEE.

Switching among pulse-generation regimes in passively mode-locked fibre laser by adaptive filtering

We show both numerically and experimentally that dispersion management can be realized by manipulating the dispersion of a filter in a passively mode-locked fibre laser. A programmable filter the dispersion of which can be software configured is employed in the laser. Solitons, stretched-pulses, and dissipative solitons can be targeted reliably by controlling the filter transmission function only, while the length of fibres is fixed in the laser. This technique shows remarkable advantages in controlling operation regimes in ultrafast fibre lasers, in contrast to the traditional technique in which dispersion management is achieved by optimizing the relative length of fibres with opposite-sign dispersion. Our versatile ultrafast fibre laser will be attractive for applications requiring different pulse profiles such as in optical signal processing and optical communications.

Menedzsmentképességek és döntéshozatali közelítésmódok longitudinális elemzése a versenyképesség-kutatások alapján (Longitudinal analysis of management capabilities and decision making approaches based on the competitiveness researches)

Számos korábbi kutatás – köztük a szerzők korábbi vizsgálatai is – azt mutatja, hogy a menedzsmentképességek és a vállalatok versenyképessége között pozitív kapcsolat áll fenn, a jobban teljesítő és a proaktívabb vállalatok rendre felkészültebb, jobb vezetői képességekkel bíró, kockázatvállalóbb vezetőkkel rendelkeznek. Az is megfigyelhető, hogy az ebből a nézőpontból sikeresebben működő vállalatok döntéseiben az átlagosnál is erősebben érvényesül a racionális közelítésmód, melynek alkalmazásával a menedzserek az optimális cselekvési alternatíva kiválasztására törekszenek. A cikkben a szerzők az elmúlt 15 év versenyképességi kutatásainak tapasztalatait összegzik, kiemelt hangsúlyt helyezve a legfrissebb felmérés eredményeire. ________________ The article summarizes the main findings of the Competitiveness Research Program with respect to the skills and capabilities of the Hungarian managers and the decision making approaches they use during their work. The results of the four surveys conducted in 1996, 1999, 2004 and 2009 are fairly stable over time: practice minded behavior, professional expertise, and problem solving skills are on the top of the list of the most developed skills of the Hungarian executives. The rational approach is the most popular among the most widespread decision making models in the authors’ sample which is rather alarming since the present turbulent economic environment may demand more adaptive and intuitive approaches.

Knowledge representation and evaluation an ontology-based knowledge management approach

Competition between Higher Education Institutions is increasing at an alarming rate, while changes of the surrounding environment and demands of labour market are frequent and substantial. Universities must meet the requirements of both the national and European legislation environment. The Bologna Declaration aims at providing guidelines and solutions for these problems and challenges of European Higher Education. One of its main goals is the introduction of a common framework of transparent and comparable degrees that ensures the recognition of knowledge and qualifications of citizens all across the European Union. This paper will discuss a knowledge management approach that highlights the importance of such knowledge representation tools as ontologies. The discussed ontology-based model supports the creation of transparent curricula content (Educational Ontology) and the promotion of reliable knowledge testing (Adaptive Knowledge Testing System).

Adaptív döntéshozatal a beszállítóválasztás példáján (Adaptive decision-making on example of the supplier selection)

Ez a tanulmány a projektvezetési szakirodalomban kialakult ismeretanyagot szem előtt tartva (noha tételesen nem hivatkozva arra) tárja fel azt a sajátos és tipikusnak nevezhető kontextust, amelyben a projektalapú szervezetek projektmarketing tevékenysége megnyilvánul. A tanulmány célja tehát nem magának a projektmarketingnek a kérdéskörére irányul, hanem elsősorban annak projektspecifikus kontextusára. Jellegét illetően a tanulmány spekulatív jellegű, vagyis lényegét tekintve nem empirikus kutatási eredményekből levont következtetésekre épül. _____ The author analyses the cognitive level of individual decisions by placing the adaptive decision-maker in the centre of interest. The main question is how do adaptive processes evolve and what factors determine the adaptive mechanism. The author builds on his own qualitative study conducted with the Grounded Theory Methodology in the SME sector. The supplier selection decision is chosen from the wide range of business decisions. From the research results the two elements of the adaptive mechanism – the metastructure and the attitude set –, the process of their evolution and the factors determining this process are presented. The findings here are a middle-range theory, which can be elaborated further, but they provide some interesting insights already.

Do institutions matter in business strategy? – The changing focus of strategic management to institutions: a literature review

The post-crisis managerial literature emphasizes the roles of institutional factors in any disruption of the ecosystem of market capitalism and puts it in the middle of its analytical framework. It has become clear that nowadays, scientific discussions about the measure of increase of direct state involvement in certain economic areas has become more relevant. The socio-economic model based on market coordination was no doubt shaken by the crisis in 2008 across the world and inspired various representatives of the scientific and political community to revise their theses on coordination mechanisms that support the way out of an economic downturn. This paper intends to give a brief summary of the two leading strategic management approaches (Porter’s five forces and the resource-based view of the firm) on institutions. The author’s aim is to demonstrate that incorporation of the institution-based view into the mainstream theories can enrich the analytical framework of strategic management by providing deeper understanding of the contextual factors that underpin interactions between institutions and organizations.

Towards the formation of a sustainable South Florida: An analysis of conflict resolution and consensus building in the South Florida Everglades Ecosystem Restoration Initiative

This dissertation examines the sociological process of conflict resolution and consensus building in South Florida Everglades Ecosystem Restoration through what I define as a Network Management Coordinative Interstitial Group (NetMIG). The process of conflict resolution can be summarized as the participation of interested and affected parties (stakeholders) in a forum of negotiation. I study the case of the Governor's Commission for a Sustainable South Florida (GCSSF) that was established to reduce social conflict. Such conflict originated from environmental disputes about the Everglades and was manifested in the form of gridlock among regulatory (government) agencies, Indian tribes, as well as agricultural, environmental conservationist and urban development interests. The purpose of the participatory forum is to reduce conflicts of interest and to achieve consensus, with the ultimate goal of restoration of the original Everglades ecosystem, while cultivating the economic and cultural bases of the communities in the area. Further, the forum aim to formulate consensus through envisioning a common sustainable community by providing means to achieve a balance between human and natural systems. ^ Data were gathered using participant observation and document analysis techniques to conduct a theoretically based analysis of the role of the Network Management Coordinative Interstitial Group (NetMIG). I use conflict resolution theory, environmental conflict theory, stakeholder analysis, systems theory, differentiation and social change theory, and strategic management and planning theory. ^ The purpose of this study is to substantiate the role of the Governor's Commission for a Sustainable South Florida (GCSSF) as a consortium of organizations in an effort to resolve conflict rather than an ethnographic study of this organization. Environmental restoration of the Everglades is a vehicle for recognizing the significance of a Network Management Coordinative Interstitial Group (NetMIG), namely the Governor's Commission for a Sustainable South Florida (GCSSF), as a structural mechanism for stakeholder participation in the process of social conflict resolution through the creation of new cultural paradigms for a sustainable community. ^

Pavement performance prediction using adaptive logic networks

Pavement performance is one of the most important components of the pavement management system. Prediction of the future performance of a pavement section is important in programming maintenance and rehabilitation needs. Models for predicting pavement performance have been developed on the basis of traffic and age. The purpose of this research is to extend the use of a relatively new approach to performance prediction in pavement performance modeling using adaptive logic networks (ALN). Adaptive logic networks have recently emerged as an effective alternative to artificial neural networks for machine learning tasks. ^ The ALN predictive methodology is applicable to a wide variety of contexts including prediction of roughness based indices, composite rating indices and/or individual pavement distresses. The ALN program requires key information about a pavement section, including the current distress indexes, pavement age, climate region, traffic and other variables to predict yearly performance values into the future. ^ This research investigates the effect of different learning rates of the ALN in pavement performance modeling. It can be used at both the network and project level for predicting the long term performance of a road network. Results indicate that the ALN approach is well suited for pavement performance prediction modeling and shows a significant improvement over the results obtained from other artificial intelligence approaches. ^

3D TerraFly: Quality of service management for online interactive 3D geographic information system

3D geographic information system (GIS) is data and computation intensive in nature. Internet users are usually equipped with low-end personal computers and network connections of limited bandwidth. Data reduction and performance optimization techniques are of critical importance in quality of service (QoS) management for online 3D GIS. In this research, QoS management issues regarding distributed 3D GIS presentation were studied to develop 3D TerraFly, an interactive 3D GIS that supports high quality online terrain visualization and navigation. ^ To tackle the QoS management challenges, multi-resolution rendering model, adaptive level of detail (LOD) control and mesh simplification algorithms were proposed to effectively reduce the terrain model complexity. The rendering model is adaptively decomposed into sub-regions of up-to-three detail levels according to viewing distance and other dynamic quality measurements. The mesh simplification algorithm was designed as a hybrid algorithm that combines edge straightening and quad-tree compression to reduce the mesh complexity by removing geometrically redundant vertices. The main advantage of this mesh simplification algorithm is that grid mesh can be directly processed in parallel without triangulation overhead. Algorithms facilitating remote accessing and distributed processing of volumetric GIS data, such as data replication, directory service, request scheduling, predictive data retrieving and caching were also proposed. ^ A prototype of the proposed 3D TerraFly implemented in this research demonstrates the effectiveness of our proposed QoS management framework in handling interactive online 3D GIS. The system implementation details and future directions of this research are also addressed in this thesis. ^

Resource management and optimization in wireless mesh networks

A wireless mesh network is a mesh network implemented over a wireless network system such as wireless LANs. Wireless Mesh Networks(WMNs) are promising for numerous applications such as broadband home networking, enterprise networking, transportation systems, health and medical systems, security surveillance systems, etc. Therefore, it has received considerable attention from both industrial and academic researchers. This dissertation explores schemes for resource management and optimization in WMNs by means of network routing and network coding.^ In this dissertation, we propose three optimization schemes. (1) First, a triple-tier optimization scheme is proposed for load balancing objective. The first tier mechanism achieves long-term routing optimization, and the second tier mechanism, using the optimization results obtained from the first tier mechanism, performs the short-term adaptation to deal with the impact of dynamic channel conditions. A greedy sub-channel allocation algorithm is developed as the third tier optimization scheme to further reduce the congestion level in the network. We conduct thorough theoretical analysis to show the correctness of our design and give the properties of our scheme. (2) Then, a Relay-Aided Network Coding scheme called RANC is proposed to improve the performance gain of network coding by exploiting the physical layer multi-rate capability in WMNs. We conduct rigorous analysis to find the design principles and study the tradeoff in the performance gain of RANC. Based on the analytical results, we provide a practical solution by decomposing the original design problem into two sub-problems, flow partition problem and scheduling problem. (3) Lastly, a joint optimization scheme of the routing in the network layer and network coding-aware scheduling in the MAC layer is introduced. We formulate the network optimization problem and exploit the structure of the problem via dual decomposition. We find that the original problem is composed of two problems, routing problem in the network layer and scheduling problem in the MAC layer. These two sub-problems are coupled through the link capacities. We solve the routing problem by two different adaptive routing algorithms. We then provide a distributed coding-aware scheduling algorithm. According to corresponding experiment results, the proposed schemes can significantly improve network performance.^