DrAST - An attribute debugger for JastAdd

Here we present a solution for debugging compilers that use abstract-syntax trees as their internal structure. The solution focuses on capturing one specific state of the compilation process, and should not be confused with the more known step-by-step debugging. The goal is to visualize the current state of the abstract-syntax tree and present its data to the user in an intuitive and interactive way. We believe that deeper understanding of an abstract-syntax tree, and bugs in its structure, can be achieved by visualization of the tree. Few such debuggers exist today however, but with this master thesis we aim to fill this gap. The main feature of the developed tool DrAST is the ability to visualize the abstract-syntax tree. It is also possible to filter the tree, so that only nodes of interest are visualized, while the rest are gathered in what we call clusters. Further, DrAST can display attributes, draw references between nodes, calculate parameterized attributes and is built for further extension. DrAST mainly debugs compilers created in the attribute-grammar-based system JastAdd. By the use of Java reflection and annotations from the JastAdd system, the debugger is able to extract the abstract-syntax tree from a compiler without knowing the specific grammar. In short, DrAST provides a new solution in compiler debugging which can be of use for both students and professionals

Generation of Sparse Jacobians for the Function Mock-Up Interface 2.0

Derivatives, or Jacobians, are commonly required by numerical algorithms. Access to accurate Jacobians often improves the performance and robustness of algorithms, and in addition, efficient implementation of Jacobian computations can reduce the over-all execution time. In this paper, we present methods for computing Jacobians in the context of the Functional Mock-up Interface (FMI), and Modelica. Two prototype implementations, in JModelica.org and OpenModelica are presented and compared in industrial benchmarks

OAuth versioner 1.0a och 2.0 - En säkerhetsjämförelse

In this work two versions of Oauth have been analyzed, the protocol OAuth 1.0a and the newer framework OAuth 2.0. A higher version number is often considered a good thing, but OAuth 2.0 has encountered much criticism. It has been criticised of not being safe enough while OAuth 1.0a was criticised of being very complicated protocol to implement, which has stopped it from growing as expected. The following problem is solved with OAuth: a resource owner has resources on a server. A third party would like to use some of these resources in the resource owner's name. OAuth solves this by letting the resource owner authenticates at the server and agree that the third party is authorized to access the resources that the resource owner possesses. The result of this work led to an implementation of an OAuth client to LinkedIn on PMCG Scandinavia AB's project portal. The result is an OAuth 2.0 solution that gives LinkedIn users the ability to log in to the project portal through LinkedIn. LinkedIns OAuth 2.0 solution was considered to be sufficiently safe and much easier to implement and maintain

Productivity in relation to organization of a surgical department : a retrospective observational study

Background Responsible and efficient resource utilization are important factors in healthcare. The aim of this study was to investigate how total case time differs between two differently organized surgical departments. Methods This is a retrospective observational study of a cohort of patients undergoing elective surgery for breast cancer or malignant melanoma in a university hospital setting in Sweden. All patients were operated on by the same set of surgeons but in two different surgical departments: a general surgery (GS) and a cardiothoracic (CT) surgery department. Patients were selected to the two departments from a waiting list in the order of referral for surgery. The effect of being operated on at the CT department compared to the GS department was estimated by linear regression. Results The final study cohort comprised 349 patients in the GS department and 177 patients in the CT department. Both groups were similar regarding surgical procedures, American Society of Anesthesiologists' score, body mass index, age, sex, and the skill level of the operating surgeon. These covariates were included in the linear regression model. The total case time, defined by the Procedural Time Glossary as room set-up start to room clean-up finish, was significantly shorter for the patients who underwent a surgical procedure at the CT department compared to the GS department, even after adjusting for the background characteristics of the patients and surgeon. After adjusting for the selected covariates, the average difference in total case time between the two departments was - 30.67 min (p = 0.001). Conclusions A significantly shorter total case time was measured for operations in the CT department. Plausible explanations may be more beneficial organizational factors, such as staffing ratio, skill mix in the operating room team, and working behavioral aspects regarding resource utilization.Peer reviewe

Rethinking Human Nature: Bridging the ‘Gap’ through Landscape Analysis and Geographical Information Systems (GIS)

This paper will discuss a pedagogical approach to integrating the humanities and the natural sciences. Our approach calls for extended collaboration between the two fields and a capacity to integrate the experimental and deductive lines of reasoning within the natural sciences with the holistic and critical perspectives of the humanities. This paper will describe and discuss how this notion is applied to the construction of a pedagogical framework or a learning environment constituted from landscape theory, GIS, and pedagogical principles derived from EBL and PL. The paper highlights how a landscape approach in combination with the interactive and dynamic properties of GIS can be used as an active learning environment crossing the interfaces of the disciplines