We consider the problem of minimizing transmission energy in wireless sensor networks by taking into account that every sensor may require a different bit rate and reliability according to its particular application. We propose a cross-layer approach to tackle such a minimization in centralized networks for the total transmission energy consumption of the network: in the physical layer, for each sensor the sink estimates the channel gain and adaptively selects a modulation scheme; in the MAC layer, each sensor is correspondingly assigned a number of time slots. The modulation level and the number of allocated time slots for every sensor are constrained to attain their applications bit rates in a global energy-efficient manner. The signal-to-noise ratio gap approximation is used in our exposition in order to jointly handle required bit rates, transmission energies, and symbol error rates.

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One of the most commonly used agile methods is Scrum. Capability Maturity Model Integration for Development (CMMI-DEV) is currently the de facto framework for process improvement and for determining the organizational maturity of software development companies. CMMI-DEV and Scrum share certain characteristics, and even though they were developed for different purposes, they can be complementary to each other; and as such, they are not in competition. This paper presents a case study of the relationship between level 2 of CMMI-DEV 1.3 and Scrum. This research has focused on the relationships between Scrum and level 2 of CMMI-DEV 1.3. The objective of this research paper is to evaluate how Scrum helps implement a process model such as CMMI-DEV.A detailed case study was conducted among Spanish IT companies. The case study was designed according to established guidelines for cases studies. There were eight principal activities: case study design, case selection, case study procedures and roles, data collection, analysis, plan validity, study limitations, and reporting.The results obtained show that most of the process areas of CMMI-DEV level 2 had been improved by using Scrum. Other issues detected arose during the formal appraisals and illustrated how it is possible to verify with Scrum that the specific goals of CMMI-DEV have been implemented. In addition, it highlights how the use of open-source tools was useful in improving the process in the companies involved. Based on the case study carried out, the addition of Scrum methodologies may improve the increase in quality of software processes.

The purpose of this article is to provide an overview of academic research on professional success, using the bibliometric analysis to understand the evolution of this field between the years 1990 and 2020. The information was obtained from the publications indexed in the Scopus database, under a rigorous bibliometric process that comprises five parts: (i) criteria search of the field, (ii) selection of database and documents, (iii) inclusion and selection criteria, (iv) software and data selection, and (v) analysis and results. The results show professional success as a scientific discipline in full exponential growth, which allows us to consider the main contributions of authors, institutions, and international contributions, as well as to consider the main themes that have shaped the intellectual structure of the subject through their visualization using bibliometric maps of co-citation and co-occurrence, which combined showed eight main lines of research. The results obtained allowed us to identify patterns of convergence and divergence in various topics, which allows obtaining current and diverse information on the state of the research field’s art.

At the present time, best rules and patterns have reached a zenith in popularity and diffusion, thanks to the software community's efforts to discover, classify and spread knowledge concerning all types of rules and patterns. Rules and patterns are useful elements, but many features remain to be studied if we wish to apply them in a rational manner.The improvement in quality that rules and patterns can inject into design is a key issue to be analyzed, so a complete body of empirical knowledge dealing with this is therefore necessary. This paper tackles the question of whether design rules and patterns can help to improve the extent to which designs are easy to understand and modify. An empirical study, composed of one experiment and a replica, was conducted with the aim of validating our conjecture. The results suggest that the use of rules and patterns affect the understandability and modifiability of the design, as the diagrams with rules and patterns are more difficult to understand than non-rule/pattern versions and more effort is required to carry out modifications to designs with rules and patterns.