This paper investigates the dynamic behaviour of cable-supported glazing façades
subjected to medium-level air blast loads. Preliminary numerical studies are carried-out in
SAP2000 by means of a geometrically refined and simplified lumped-mass finite-element
numerical model, in order to assess the major effects of the design blast load in the main
façade components. As shown, both the glass panels and the cable system are able to
properly accommodate the incoming impulsive loads, typically involving extreme ...

We prove the Stechkin inequality for Fourier multipliers on variable Lebesgue spaces under some natural assumptions on variable exponents.

STUDENTS’ CONCEPTIONS ABOUT THE USE OF GRAPHING CALCULATORS ON TESTS

H. Rocha

Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa (PORTUGAL)

The assessment is considered a key element of the teaching and learning process and is often divided into two types: formative and summative. The distinction between these two types of assessment is usually made based on the moments in which it occurs and the objectives it has. Nevertheless, there are some continuities between these two types of assessment, and this leads some authors to question whether these two types of assessment should be seen as fully disjoint. Despite this, the prevailing understanding of summative assessment is that it takes place at the end of the learning process and that it is intended to classify the students.

The technology and, in particular, the graphing calculator is recognized for the impact it may have on the students’ approaches to solve mathematical questions. When technology is available, several studies point to an higher relevance of the understanding of the mathematical concepts, to an increase in graphical approaches to mathematical questions and to an increment in the use of exploratory approaches to solve the problems that are posed. Of course, all these changes will have its impact also on summative assessment moments, and specifically in testing.

Students’ conceptions about the use of technology have a deep impact on how they actually use the technology. The relevance usually attributed to tests, makes it important to understand what determines the performance of students in these moments.

This study focuses on the use of the graphing calculator at assessment moments such as tests, intending to understand the students’ conceptions related to that use. Namely it intends to analyze the impact of the students’ conceptions about Mathematics, about the use of technology to learn, and about teachers’ perspectives.

The study adopts a qualitative and interpretative methodological approach, undertaking two students’ case studies. Data were collected during one school year by semi-structured interviews, students’ observation at testing moments, and documental data gathering. All interviews were audio recorded and transcribed and the students’ observation was video recorded. Data analysis was conducted in an interpretative way.

The conclusions reached suggest that students welcome the possibility of using the graphing calculator during testing. The way this technology allows them to avoid errors, both in the calculations and in the formulas to be used, is the main reason advanced by the students. The speed of resolution, which they consider very important during testing, is another of the valued aspects. The idea of Mathematics as something that you need to understand and where knowing the right formula is not enough to achieve the right answer is pointed as the main justification for the use of this technology in tests. Nevertheless, the idea that technology should not be used seems to be always present. The impact of family ideas and, in particular, the idea that one can become dependent of the graphing calculator, seems to have some influence over the students conceptions about the use of this technology. However, the one that is undoubtedly the decisive reason for this conception is what they consider to be the opinion of a teacher. For the students, a teacher cannot agree with the use of graphing calculators in tests. And the reason given for this is related to the idea that a teacher will not be able to actually understand the students’ mathematical knowledge if he uses the graphing calculator.

Keywords: summative assessment, students’ conceptions, technology, mathematics.

In this work, a multi-objective mixed integer linear programming (moMILP) model is presented for the design and planning of sustainable closed loop supply chains. It includes strategic decisions such as facility location, definition of transportation modes, technology selection and allocation, as well as tactical decisions. The model includes four objectives: 1) The economic pillar, measured through the net present value (NPV); 2) the environmental pillar, which includes Life Cycle Assessment (LCA), through the application of the ReCiPe methodology; 3 and 4) The social pillar measured using two socio-economic indicators applied by the European Union in its Sustainable Development Strategy. The applicability of the model is demonstrated through a representative supply chain case study. Results show that the different objectives influence the supply chain structure and translate in significantly different and conflicting decisions, showing the importance of such type of models to better understand the decisions implications on the different dimensions of sustainability.

Distributed transactional memory (DTM) presents itself as a highly expressive and programmer friendly model for con- currency control in distributed programming. Current DTM systems make use of both data distribution and replication as a way of providing scalability and fault tolerance, but both techniques have advantages and drawbacks. As such, each one is suitable for different target applications, and deployment environments. In this paper we address the support of different data replication models in DTM. To that end we propose ReDstm, a modular and non-intrusive framework for DTM, that supports multiple data replication models in a general purpose programming language (Java). We show its application in the implementation of distributed software transactional memories with different replication models, and evaluate the framework via a set of well-known benchmarks, analysing the impact of the different replication models on memory usage and transaction throughput.

Distributed transactional memory (DTM) presents itself as a highly expressive and programmer friendly model for concurrency control in distributed programming. Current DTM systems make use of both data distribution and replication as a way of providing scalability and fault tolerance, but both techniques have advantages and drawbacks. As such, each one is suitable for different target applications, and deployment environments. In this paper we address the support of different data replication models in DTM. To that end we propose ReDstm, a modular and non-intrusive framework for DTM, that supports multiple data replication models in a general purpose programming language (Java). We show its application in the implementation of distributed software transactional memories with different replication models, and evaluate the framework via a set of well-known benchmarks, analysing the impact of the different replication models on memory usage and transaction throughput.

Non-steroidal anti-inflammatory drugs exert their pharmacological activity through inhibition of cyclooxygenase 1 and 2 (COX-1 and COX-2). Recent research suggests that a balanced inhibition of both COX-1 and COX-2 is the key to reduce the side-effects exhibited by COX inhibitors. We developed new benzimidazole-based compounds that showed a balanced COX inhibition, supported by molecular docking screening. The human whole blood assays demonstrated that the ester derivatives were potent inhibitors. Competitive saturation transfer difference (STD)-NMR experiments, in the presence of COX-2, using naproxen and diclofenac demonstrated that ester derivatives do not compete with diclofenac for the same binding site, but compete with the allosteric inhibitor naproxen. Combination of NMR spectroscopy with molecular docking has permitted us to detect a new naproxen-like inhibitor, which could be used for future drug development.

Technology assessment (TA) and TA-like activities in countries like Japan have a unique history and continue to play a role in contemporary science, technology, and innovation (STI) processes. The aim of the discussion of TA’s experience in East Asia is how STI governance is locally enacted in Asian knowledge-driven economies, as TA activities develop in conjunction with STI policies and programs. To render these processes, policies, and programs visible and to understand their implications for STI governance, a panel at the Berlin conference on TA discussed contributions that described and conceptualized, for example, how TA activities have emerged in Asian knowledge-based economies (KBE), in which particular forms (e.g., academic and parliamentary TA programs), to which technologies and/or actors they are linked, and which methods are used and why. The panel also sought to compare and contrast how TA is (or is not) institutionalized in Asian countries and regions, and to point to prospects for expansion of TA capacity. In doing so, the panellists placed the development of TA in a historical, sociological, and comparative perspective, and opened space for critical reflection on the potential, problems, and limitations associated with initiating TA in Asia and with KBEs overall

The evolution of technology has risen new possibilities in the so called Natural User Interfaces research area. Among distinct initiatives, several researchers are working with the existing sensors towards improving the support to gesture languages. This article tackles the recognition of gestures, using the Kinect sensor, in order to create a gesture library and support the gesture recognition processes afterwards.

A spreadsheet usually starts as a simple and single- user software artifact, but, as frequent as in other software systems, quickly evolves into a complex system developed by many actors. Often, different users work on different aspects of the same spreadsheet: while a secretary may be only involved in adding plain data to the spreadsheet, an accountant may define new business rules, while an engineer may need to adapt the spreadsheet content so it can be used by other software systems. Unfortunately, spreadsheet systems do not offer modular mechanisms, and as a consequence, some of the previous tasks may be defined by adding intrusive “code” to the spreadsheet.

In this paper we go through the design and implementation of an aspect-oriented language for spreadsheets so that users can work on different aspects of a spreadsheet in a modular way. For example, aspects can be defined in order to introduce new business rules to an existing spreadsheet, or to manipulate the spreadsheet data to be ported to another system. Aspects are defined as aspect-oriented program specifications that are dynamically woven into the underlying spreadsheet by an aspect weaver. In this aspect-oriented style of spreadsheet development, different users develop, or reuse, aspects without adding intrusive code to the original spreadsheet. Such code is added/executed by the spreadsheet weaving mechanism proposed in this paper.

In this session we review the Upper Cretaceous marine amniote records from the west coasts of North America and Africa. Recent work by our group in Angola, on the west coast of Africa, has opened up new fossiliferous localities, producing well-preserved turtles, plesiosaurs, and mosasaurs, ranging in age from Late Turonian to Late Maastrichtian. These African localities were deposited in arid latitudes and highly productive upwelling zones along the passive margin of a growing South Atlantic Ocean. The fossil record of Cretaceous marine amniotes from the West Coast of North America is relatively meager when compared to the African record and the prolific fossil beds laid down in the epicontinental seas of the Western Interior Seaway and northern Europe. Nonetheless, these localities provide an important glimpse of a marine ecosystem that developed on the active margins of a deep ocean basin. Historically considered to be depauperate and endemic, the west coast fauna was characterized by unusual forms such as Plotosaurus, arguably one of the most derived mosasaurs; however, in recent years, additional taxa have been described, revealing species diversity and ecological partitioning within these communities and in some cases, faunal interchange with other regions. The large quantity of well-preserved fossils from the west coast of Africa is influenced in part by its paleogeographic position, deposited within highly productive areas of Hadley Cell controlled upwelling zones. By contrast, the North American west coast localities have been deposited in temperate and higher latitudes since the Late Cretaceous. Nonetheless, the North American and African faunas share some common characteristics in a possessing a mix of endemic and more cosmopolitan forms. Habitat partitioning reflected in tooth form and body size is comparable between the Angolan and the North American west coast, and there is remarkable convergence in taxa which appear to exploit certain like-niches.