Construction safety and digital design: a review

As digital technologies become widely used in designing buildings and infrastructure, questions arise about their impacts on construction safety. This review explores relationships between construction safety and digital design practices with the aim of fostering and directing further research. It surveys state-of-the-art research on databases, virtual reality, geographic information systems, 4D CAD, building information modeling and sensing technologies, finding various digital tools for addressing safety issues in the construction phase, but few tools to support design for construction safety. It also considers a literature on safety critical, digital and design practices that raises a general concern about ‘mindlessness’ in the use of technologies, and has implications for the emerging research agenda around construction safety and digital design. Bringing these strands of literature together suggests new kinds of interventions, such as the development of tools and processes for using digital models to promote mindfulness through multi-party collaboration on safet

Single system image: A survey

Single system image is a computing paradigm where a number of distributed computing resources are aggregated and presented via an interface that maintains the illusion of interaction with a single system. This approach encompasses decades of research using a broad variety of techniques at varying levels of abstraction, from custom hardware and distributed hypervisors to specialized operating system kernels and user-level tools. Existing classification schemes for SSI technologies are reviewed, and an updated classification scheme is proposed. A survey of implementation techniques is provided along with relevant examples. Notable deployments are examined and insights gained from hands-on experience are summarized. Issues affecting the adoption of kernel-level SSI are identified and discussed in the context of technology adoption literature

Lightweight Environment for Cyber Security Education

The use of physical systems and Virtual Machines has become inefficient and expensive for creating tailored, hands-on exercises for providing cyber security training. The main purpose of this project is to directly address these issues faced in cyber security education with the help of Docker containers. Using Docker, a lightweight and automated platform was developed for creating, sharing, and managing hands-on exercises. With the help of orchestration tools, this platform provides a centralized point to monitor and control the systems and exercises with a high degree of automation. In a classroom/lab environment, this infrastructure enables instructors and students not only to share exercises but also helps create and deploy exercises more easily. By streamlining the end to end delivery and deployment of the exercises, instructors can now efficiently make use of the class/lab hours in educating the students rather than performing system administration tasks

Arquitecturas para sistemas de informação baseados em cloud computing

Mestrado em Engenharia dos Computadores e TelemáticaEste trabalho faz um apanhado do panorama actual no que diz respeito a Cloud computing. Começa por analisar a definição proposta pelo NIST e cate-gorizar vários serviços comerciais de acordo com as categorias propostas nes-sa definição. De seguida, são analisadas as implementações grátis disponíveis em licenças Open Source e chega-se à conclusão que para Clouds do tipo IaaS já existem várias implementações, algumas com boa qualidade, mas que na área de PaaS ainda existe muito trabalho a ser feito antes de se chegar a uma imple-mentação com funcionalidade comparável à dos serviços comerciais existen-tes. Após uma breve análise sobre a integração de SOA com as facilidades do Cloud computing, chegou-se à conclusão que PaaS se apresenta como o modelo de serviço mais adequando para desenvolver aplicações SOA. Visto que não existe ainda nenhum PaaS livre, e que os existentes apresentam problemas sérios de vendor lock in, é especificada uma framework completa, portátil e aberta que permitirá implementar um serviço do tipo PaaS em infra-estrutura privada ou sobre algum dos IaaS existentes. O PaaS especificado baseia-se, sempre que possível, em tecnologias existen-tes, concluindo-se que apenas a tecnologia de armazenamento de dados estruturados está aquém do necessário para a implementação. Deixa-se para o futuro a implementação dos vários módulos que permitirão a integração dos vários componentes da PaaS, no entanto sempre que possível, são sugeridas tecnologias a utilizar de forma a manter a implementação aberta e portátil.This work sums up the current situation of Cloud computing. It starts by per-forming an analysis of the NIST definition draft, and categorizing some com-mercial services into the categories proposed by the referred definition. Next, the free implementations distributed under an Open Source license are analyzed, and the conclusion is that there are some high quality IaaS cloud implementations, but the PaaS area still needs a lot of work before the functio-nality of a free implementation is comparable to that of the commercial services available. After a brief analysis of the integration of SOA and Cloud computing, the con-clusion is that PaaS presents the most adequate service model for the devel-opment of SOA applications. Given that, up to the moment, there is no free PaaS, and that the existing ones present serious vendor lock in problems, a complete, portable, and open framework that allows the deployment of a PaaS type service on private or on IaaS infrastructure is specified. The specified PaaS is based on current technology whenever possible, with exception of the storage of structured data that is not up to the requirements yet. The implementation of the modules required to integrate the various PaaS components is left as future work. Yet, whenever possible, suggestions are made about usable technologies that will allow the PaaS to remain portable and open

A comparison of statistical machine learning methods in heartbeat detection and classification

In health care, patients with heart problems require quick responsiveness in a clinical setting or in the operating theatre. Towards that end, automated classification of heartbeats is vital as some heartbeat irregularities are time consuming to detect. Therefore, analysis of electro-cardiogram (ECG) signals is an active area of research. The methods proposed in the literature depend on the structure of a heartbeat cycle. In this paper, we use interval and amplitude based features together with a few samples from the ECG signal as a feature vector. We studied a variety of classification algorithms focused especially on a type of arrhythmia known as the ventricular ectopic fibrillation (VEB). We compare the performance of the classifiers against algorithms proposed in the literature and make recommendations regarding features, sampling rate, and choice of the classifier to apply in a real-time clinical setting. The extensive study is based on the MIT-BIH arrhythmia database. Our main contribution is the evaluation of existing classifiers over a range sampling rates, recommendation of a detection methodology to employ in a practical setting, and extend the notion of a mixture of experts to a larger class of algorithms

Provisioning of customizable pattern-based software artifacts into Cloud environments

Software architects and engineers frequently face reoccurring problems, when implementing cloud computing applications, leading towards reduced productivity and an increased time to market factor. These issues can be faced by the commonly known concept of patterns. Thus, researchers identified and documented patterns for the cloud computing domain, to preserve gained knowledge about cloud application architectures and service offerings [FLMS11, FLR+12]. These patterns can be used to from the foundation of aggregated cloud computing applications. Dependent on the corresponding cloud service model, such applications require different provisioning steps, which can be performed by individually implemented actions or can be executed by pre-provided cloud services. Yet, these cloud computing patterns are offered in non-technical, written form, which does not allow to aggregate corresponding implementation binaries to pattern-based applications. Therefore, this thesis combines software product line engineering methods, open source build management tools, and open source infrastructure management tools to implement a software product line for cloud computing patterns, which allows to reduce human-driven efforts to implement aggregated cloud computing applications. This approach enables the possibility to create, aggregate and customize cloud computing pattern implementations; and store them in a so-called pattern template catalogue. Hence, each pattern, stored in such a catalogue, is associated with so-called customization points, which allow to adapt instantiated patterns to individual needs. To accomplish these challenges, Apache Maven [Mava], an open source build management tool, is extend with means to create, customize and aggregate pattern-based cloud computing applications. Corresponding provisioning tasks are accomplished, by combining PuppetLabs’ Puppet [Pup] and pre-offered cloud provisioning services. Pattern-specific customization points are stored within a serialized, so-called variability model, embedded in each pattern. Moreover, the presented structure model allows to decouple direct pattern dependencies through common interfaces, which allows to switch pattern implementations transparently, without adapting dependent patterns. Furthermore, combinable reference patterns are presented and discussed, to provide a proof of concept of the implemented software product line approach

Security Audit Compliance for Cloud Computing

Cloud computing has grown largely over the past three years and is widely popular amongst today's IT landscape. In a comparative study between 250 IT decision makers of UK companies they said, that they already use cloud services for 61% of their systems. Cloud vendors promise "infinite scalability and resources" combined with on-demand access from everywhere. This lets cloud users quickly forget, that there is still a real IT infrastructure behind a cloud. Due to virtualization and multi-tenancy the complexity of these infrastructures is even increased compared to traditional data centers, while it is hidden from the user and outside of his control. This makes management of service provisioning, monitoring, backup, disaster recovery and especially security more complicated. Due to this, and a number of severe security incidents at commercial providers in recent years there is a growing lack of trust in cloud infrastructures. This thesis presents research on cloud security challenges and how they can be addressed by cloud security audits. Security requirements of an Infrastructure as a Service (IaaS) cloud are identified and it is shown how they differ from traditional data centres. To address cloud specific security challenges, a new cloud audit criteria catalogue is developed. Subsequently, a novel cloud security audit system gets developed, which provides a flexible audit architecture for frequently changing cloud infrastructures. It is based on lightweight software agents, which monitor key events in a cloud and trigger specific targeted security audits on demand - on a customer and a cloud provider perspective. To enable these concurrent cloud audits, a Cloud Audit Policy Language is developed and integrated into the audit architecture. Furthermore, to address advanced cloud specific security challenges, an anomaly detection system based on machine learning technology is developed. By creating cloud usage profiles, a continuous evaluation of events - customer specific as well as customer overspanning - helps to detect anomalies within an IaaS cloud. The feasibility of the research is presented as a prototype and its functionality is presented in three demonstrations. Results prove, that the developed cloud audit architecture is able to mitigate cloud specific security challenges

DVCL:A Distributed Virtual Computer Lab for Security and Network Education

Teaching networking and IT security in higher education requires a safeplayground for students, where they can safely carry out hands-on exercises.This safe playground is known as a computer lab. Universities have todesign and to provide such a lab with respect to certain criteria, e.g.technical opportunities, educational requirements and demands of thelearners. Since there is no one-size-fits-all lab, the labs will be designed tofit into a certain context and thus have own strengths and weaknesses.In this thesis, we investigate and work with two established labs, whichwere designed for hands-on experiences in networking and it security courses.These labs are predominantly different but have an essential overlap ineducational requirements.One lab is developed by the Open University. It is dedicated for distancelearning. It is based on virtualization and every student is able to startthis lab on his own computer. Students can work out exercises wheneverand wherever they want. A shortcoming however is that students have towork alone, (distant) group work is not possible due to the isolated labarchitecture. This lab is the technical base for our research.The other lab is developed by the Cologne University. It is a physicallab, dedicated for on-campus courses and thus it is not portable. Butstudents can meet in the lab, work in groups and are able to get supportfrom a course advisor, who is also able to verify exercises. A shortcominghowever is that students must be present (they have to travel to theuniversity) and they are dependent on the opening hours of the laboratoryand the availability of the course advisers.In two research parts, we show how such two different lab approachescan be combined and what can be achieved.The first research part is about design issues.Initially, we enable group work in our lab for distance education, sincegroup work is an essential part in on-campus classes. Also remote studentsshould be able to work together. Since the lab is designed as an isolatedsystem, the challenge is to connect two of them on the network level butwithout creating a potential bridge between the isolated and the outsideworld. We achieved this by adding a communication interface to the labarchitecture. This communication interface consists of a ghost host toextract and inject network packets, and a remote bridge endpoint, totransport these packets between remote ghost hosts across an intermediateconnection, e.g. the internet. The developed prototype is called DistributedVirtual Computer Lab (DVCL) and enables to connect two or more distantlabs while preserving the isolated character.The DVCL is then extended and improved by a central authority (CA).While the point-to-point connection of the communication interface canconnect two remote networks in a handy way, more connections requirecareful planning by the students. We show that a CA simplifies the usageof our DVCL for the students (and also for academic staff) and in additionto it avoids administrative configuration errors while connecting remotelabs, e.g. a circular flow which leads to an unusable lab.The first part is completed by two applicability enhancements. Thefirst enhancement covers and resolves security issues in order to pushour prototypical implementation of the DVCL and the CA closer to aproductive learning environment. The second enhancement introduces aGraphical User Interface to increase the usability of the DVCL.The second research part is about educational aspects.In the first part, we assume that working independent from a physicalon-campus lab as well as group work is essential for our students. Ourevaluation of more than 200 students participating in an on-campus networkingcourse shows, that nearly half of the students actually say, thatthey would like to work independently from the university at least partiallyand they would welcome the introduction of an e-learning system. Inaddition, a predominant majority think of working in groups as well asreceiving guidance and feedback as crucial to their learning success. Thisresult justifies and confirms our research and also reveals an additional requirement.The challenge is to provide feedback and guidance to a student, who isworking on an exercise and a human course advisor is not available. Thisis e.g. when students use the DVCL at home in the evening hours. Weshow, that captured network traffic of a lab can give some indication ofwhat a student has already configured according to a certain exercise. Weuse this insight to develop an Electronic Exercise Assistant. This softwareprogram is able to recognize the progress of an exercise and can provideappropriate feedback and support, based on preloaded rules and conditions.This significantly improves the learning situation for students workingremotely in lab. Besides this automatic support, the exercise assistant canverify intermediate and complete solutions of an exercise.The second part is completed by an educational enhancement. Ourevaluation and also own observations show, that a lab is more than aroom with computer and network facilities. Rather it is a social placewhere students e.g. meet, form learning groups, talk and discuss. Weuse these insights and enhance the DVCL to support social interactions.Based on our on-campus lab as source, we model a set of communicational,organizational as well as educational activities and implement them in ourDVCL. The result shows, that our DVCL prototype is no longer a technicalplatform but a virtual place, where students can meet, communicate,arrange learning groups, exchange experiences and work on exercises.This thesis shows that aspects of our two different lab environments canbe combined. Our resulting Distributed Virtual Computer Lab incorporatesstrengths of each source lab. It is a gain for distance teaching as well as foron-campus classes. Remote students are now able to utilize the lab being avirtual classroom, where they can learn in groups, assisted by an electronicadvisor and without the need for a face-to-face meeting. On-campus classescan offer students a new learning environment, where they can learn in aclassroom character without the need to travel to the university