How to select measures for decision support systems - An optimization approach integrating informational and economic objectives

It is still an open issue of designing and adapting (data-driven) decision support systems and data warehouses to determine relevant content and in particular (performance) measures. In fact, some classic approaches to information requirements determination such as Rockart’s critical success factors method help with structuring decision makers’ information requirements and identifying thematically appropriate measures. In many cases, however, it remains unclear which and how many measures should eventually be used. Therefore, an optimization model is presented that integrates informational and economic objectives. The model incorporates (statistic) interdependencies among measures – i. e. the information they provide about one another –, decision makers’ and reporting tools’ ability of coping with information complexity as well as negative economic effects due to measure selection and usage. We show that in general the selection policies of all-or-none or themore- the-better are not reasonable although they are often conducted in business practice. Finally, the model’s application is illustrated by the German business-to-business sales organization of a global electronics and electrical engineering company as example. In this position paper we discuss the importance of Green IT as a new research field that investigates all the environmental and energy issues related to IT and information systems in general. In particular we focus on the energy consumption of software applications, which is amplified by all the above IT layers in a data center and thus is worth a greater attention. By adopting a top-down approach, we address the problem from a logical perspective and try to identify the original cause that leads to energy consumption, i.e. the elaboration of information. We propose a research roadmap to identify a set of software complexity and quality metrics that can be used to estimate energy consumption and to compare specific software application

A Multi-Precision Bit-Serial Hardware Accelerator IP for Deep Learning Enabled Internet-of-Things

Deep Neural Networks (DNNs) computation-hungry algorithms demand hardware platforms capable of meeting rigid power and timing requirements. We introduce the Serial-MAC-engine (SMAC-engine), a fully-digital hardware accelerator for inference of quantized DNNs suitable for integration in a heterogeneous System-on-Chip (SoC). The accelerator is completely embedded in the form of a Hardware Processing Engine (HWPE) in the PULPissimo platform, a RISCV-based programmable architecture that targets the computational requirements of IoT applications. The SMAC-engine supports configurable precision for both weights (8/6/4 bits) and activations (8/4 bits), with scalable performance. Results in 65 nm technology demonstrate that the serial-MAC approach enables the accelerator to achieve a maximum throughput of 14.28 GMAC/s, consuming 0.58 pJ/MAC @ 1.0 V when operating at a precision of 4 bits for weights and 8 bits for activations

The economics of community open source software projects: an empirical analysis of maintenance effort

Previous contributions in the empirical software engineering literature have consistently observed a quality degradation effect of proprietary code as a consequence of maintenance. This degradation effect, referred to as entropy effect, has been recognized to be responsible for significant increases in maintenance effort. In the Open Source context, the quality of code is a fundamental design principle. As a consequence, the maintenance effort of Open Source applications may not show a similar increasing trend over time. The goal of this paper is to empirically verify the entropy effect for a sample of 4,289 community Open Source application versions. Analyses are based on the comparison with an estimate of effort obtained with a traditional effort estimation model. Findings indicate that community Open Source applications show a slower growth of maintenance effort over time, and, therefore, are less subject to the entropy effect

Management of displaced radial neck fractures in children: Percutaneous pinning vs. elastic stable intramedullary nailing

Background: The treatment of radial neck fractures in children varies according to the displacement, angulation, and skeletal maturity. There is a general agreement that displaced radial neck fractures with more than 30 angulations (Judet type III and IV fractures) should be surgically treated. There are several treatment possibilities for Judet type III and IV fractures including percutaneous pin reduction, elastic stable intramedullary nailing (ESIN), and open reduction with or without internal fixation. In this retrospective study we compared the clinical and radiographical outcomes, and complications following intramedullary versus percutaneous pinning in displaced radial neck fractures in children. Materials and methods: Between 2000 and 2011, 20 patients were treated using closed reduction: in 12 cases we used percutaneous pinning, and in 8 cases we used ESIN. According to Judet classification the two groups were composed as follows: 10 (77 %) type III and 3 (23 %) type IV fractures in the percutaneous pinning group; 4 (57 %) type III, and 3 (43 %) type IV fractures in the ESIN group. Results: After an average of 42 months, excellent results in Mayo elbow performance scores (MEPS) were obtained in 71 and 69 % of ESIN and percutaneous pinning groups respectively, with good results in the remaining cases apart from one fair case (8 %) in the percutaneous pinning group. After a radiological evaluation, all fractures healed in excellent or good alignment. When comparing the two groups, the subjects treated with the ESIN technique had higher range of motion (ROM) in flexion, extension and pronation. No patients developed complications, except three cases of asymptomatic enlargements of the radial head, reported only in the percutaneous pinning group. Conclusion: In this research the clinical outcome, assessed with the MEPS, and the radiological alignment, were comparable between the subjects that were treated with percutaneous pinning and those with ESIN techniques; whereas the ESIN technique demonstrated higher ROM in flexion, extension and pronation. The ESIN technique seems to be the ideal approach both for the higher ROM values and for the absence of complications. © 2012 The Author(s)

Efficiency implications of open source commonality and reuse

This paper analyzes the reuse choices made by open source developers and relates them to cost efficiency. We make a distinction between the commonality among applications and the actual reuse of code. The former represents the similarity between the requirements of different applications and, consequently, the functionalities that they provide. The latter represents the actual reuse of code. No application can be maintained for ever. A fundamental reason for the need for periodical replacement of code is the exponential growth of costs with the number of maintenance interventions. Intuitively, this is due to the increasing complexity of software that grows in both size and coupling among different modules. The paper measures commonality, reuse and development costs of 26 open-source projects for a total of 171 application versions. Results show that reuse choices in open-source contexts are not cost efficient. Developers tend to reuse code from the most recent version of applications, even if their requirements are closer to previous versions. Furthermore, the latest version of an application is always the one that has incurred the highest number of maintenance interventions. Accordingly, the development cost per new line of code is found to grow with reuse

3D reconstruction of an underwater archaelogical site: comparison between low cost cameras

The 3D reconstruction with a metric content of a submerged area, where objects and structures of archaeological interest are found, could play an important role in the research and study activities and even in the digitization of the cultural heritage. The reconstruction of 3D object, of interest for archaeologists, constitutes a starting point in the classification and description of object in digital format and for successive fruition by user after delivering through several media. The starting point is a metric evaluation of the site obtained with photogrammetric surveying and appropriate 3D restitution. The authors have been applying the underwater photogrammetric technique since several years using underwater digital cameras and, in this paper, digital low cost cameras (off-the-shelf). Results of tests made on submerged objects with three cameras are presented: (c) Canon Power Shot G12, (c) Intova Sport HD e (c) GoPro HERO 2. The experimentation had the goal to evaluate the precision in self-calibration procedures, essential for multimedia underwater photogrammetry, and to analyze the quality of 3D restitution. Precisions obtained in the calibration and orientation procedures was assessed by using three cameras, and an homogeneous set control points. Data were processed with (c) Agisoft Photoscan. Successively, 3D models were created and the comparison of the models derived from the use of different cameras was performed. Different potentialities of the used cameras are reported in the discussion section. The 3D restitution of objects and structures was integrated with sea bottom floor morphology in order to achieve a comprehensive description of the site. A possible methodology of survey and representation of submerged objects is therefore illustrated, considering an automatic and a semi-automatic approach

Comparison between absorbable pins and mini-screw fixations for the treatment of radial head fractures Mason type II-III

Background: The treatment of comminuted radial head fractures can include prosthetic replacement or open reduction and internal fixation. The purpose of this study is to evaluate the results of two different internal fixation systems for Mason type II-III radial head fractures. Methods: Between 2005 and 2015, 82 patients were treated using pins and 65 patients by mini-screws. The follow-up protocol included: a clinical evaluation 15 days after surgery, and clinical and radiographic evaluations performed at 30 and 60 day intervals, unless any complications were reported by the patient. Over a period of at least 12-months of follow-up, patients were checked and interviewed. Clinical examinations included elbow range of motion (ROM), arm, shoulder and hand Disabilities, (DASH), and the Mayo Elbow Performance Score (MEPS). Results: Sixty-one subjects who had been treated with mini-screws were clinically reviewed at a mean 47.3 \ub1 35.8 month of follow-up; all patients who had been treated using absorbable pins were evaluated at a mean 82.5 \ub1 20.6 month of follow-up. No significant statistically differences were observed between the two groups in the mean ROM, DASH, and MEPS scores. Residual pain was reported in 15.8%of the patients treated by pins and 9.2% patients treated by mini-screws. Secondary displacement of fracture fragments was observed in 8.5% patients treated by pins and 1.6% using mini-screws. Conclusions: Both absorbable pins and mini-screws provided adequate strength and rigidity, allowing good clinical and functional scores at a mid-term follow-up. However, a higher rate of secondary displacement of the fracture fragments was reported among subjects who had been treated using absorbable pins