Reinforcement Learning for Route Optimization with Robustness Guarantees

Application of deep learning to NP-hard combinatorial optimization problems is an emerging research trend, and a number of interesting approaches have been published over the last few years. In this work we address robust optimization, which is a more complex variant where a max-min problem is to be solved. We obtain robust solutions by solving the inner minimization problem exactly and apply Reinforcement Learning to learn a heuristic for the outer problem. The minimization term in the inner objective represents an obstacle to existing RL-based approaches, as its value depends on the full solution in a non-linear manner and cannot be evaluated for partial solutions constructed by the agent over the course of each episode. We overcome this obstacle by defining the reward in terms of the one-step advantage over a baseline policy whose role can be played by any fast heuristic for the given problem. The agent is trained to maximize the total advantage, which, as we show, is equivalent to the original objective. We validate our approach by solving min-max versions of standard benchmarks for the Capacitated Vehicle Routing and the Traveling Salesperson Problem, where our agents obtain near-optimal solutions and improve upon the baselines.

Teacher and actor perceptions of a recent journey involving clinical simulation

INTRODUCTION: Medical education is under many modifications, insertions and new perspectives on the learning teaching process, and the realistic simulation is one of these changes. It includes technical skills, but also attitudinal skills. The original idea of simulation is to integrate theoretical knowledge, skills and attitude. OBJECTIVES: to tell the experience of building a simulation core in our institution, with faculty development and culture changes. METHODS: using the cartography, 04 teachers and 02 female actors told their narratives by memories and reflections about the path travelled and the knowledge built. RESULTS AND DISCUSSION: each one experience on the first simulation scenario in 2018.2. We reached the original objective (students’ participation and study), but also the depth of each one experience and reflection. There was a balance between technique and sensibility. The actor’s role to build and concretize the project was essential in this balance. CONCLUSIONS: the simulation strengthened the attitudinal competences, promoted the faculty development and showed the importance to put together art and technique on the health professional training.

A Redistributed Bundle Algorithm Based on Local Convexification Models for Nonlinear Nonsmooth DC Programming

For nonlinear nonsmooth DC programming (difference of convex functions), we introduce a new redistributed proximal bundle method. The subgradient information of both the DC components is gathered from some neighbourhood of the current stability center and it is used to build separately an approximation for each component in the DC representation. Especially we employ the nonlinear redistributed technique to model the second component of DC function by constructing a local convexification cutting plane. The corresponding convexification parameter is adjusted dynamically and is taken sufficiently large to make the ”augmented” linearization errors nonnegative. Based on above techniques we obtain a new convex cutting plane model of the original objective function. Based on this new approximation the redistributed proximal bundle method is designed and the convergence of the proposed algorithm to a Clarke stationary point is proved. A simple numerical experiment is given to show the validity of the presented algorithm.

Voices in Space or the Contemporary Realism in the Pedagogy of the Future Opera Singer

The Romanian opera and operetta repertoire is a constant objective in the Opera Class of the Faculty of Performing, Composition, and Musical Theoretical Studies in “George Enescu” National University of Arts from Iași. The stylistic diversity and the richness of the drama make not only an important instrument for the study out of it, but also a moral debt for the knowledge and transmission of a music whose beauty – once (re)discovered – is a source of enchantment for the artists, as well as for the public. If in the beginning of the professional route singing in the mother tongue facilitates the work and the study of the opera singer, over time this option may enter an ethic of the performer, happily completing his repertoire. Although one of our main goals is to guide the students, future opera singers, to gain and to develop their acting skills so as to be natural and convincing on stage, contemporary realism does not exclude experiments. Having this in mind and in order to make studentsʼ work visible, we made an experimental video document, based on a first selection from our recitals, which is aimed to let the audience take a glance into the intimacy of our class study on Romanian opera and operetta, both from the musical and drama perspective. By changing the original objective – the entire presentation in semester exams of studentsʼ classroom work – the fragmentary nature of the processing gives a certain dynamism to our work. Changing the purpose brings things to a new light, the artistic overbearing the pedagogical, and last but not least, the Romanian music proving that it supports an experimental treatment.

Accelerating the Search of Differential and Linear Characteristics with the SAT Method

The introduction of the automatic search boosts the cryptanalysis of symmetric-key primitives to some degree. However, the performance of the automatic search is not always satisfactory for the search of long trails or ciphers with large state sizes. Compared with the extensive attention on the enhancement for the search with the mixed integer linear programming (MILP) method, few works care for the acceleration of the automatic search with the Boolean satisfiability problem (SAT) or satisfiability modulo theories (SMT) method. This paper intends to fill this vacancy. Firstly, with the additional encoding variables of the sequential counter circuit for the original objective function in the standard SAT method, we put forward a new encoding method to convert the Matsui’s bounding conditions into Boolean formulas. This approach does not rely on new auxiliary variables and significantly reduces the consumption of clauses for integrating multiple bounding conditions into one SAT problem. Then, we evaluate the accelerating effect of the novel encoding method under different sets of bounding conditions. With the observations and experience in the tests, a strategy on how to create the sets of bounding conditions that probably achieve extraordinary advances is proposed. The new idea is applied to search for optimal differential and linear characteristics for multiple ciphers. For PRESENT, GIFT-64, RECTANGLE, LBlock, TWINE, and some versions in SIMON and SPECK families of block ciphers, we obtain the complete bounds (full rounds) on the number of active S-boxes, the differential probability, as well as the linear bias. The acceleration method is also employed to speed up the search of related-key differential trails for GIFT-64. Based on the newly identified 18-round distinguisher with probability 2−58, we launch a 26-round key-recovery attack with 260.96 chosen plaintexts. To our knowledge, this is the longest attack on GIFT-64. Lastly, we note that the attack result is far from threatening the security of GIFT-64 since the designers recommended users to double the number of rounds under the related-key attack setting.

Getting RCEP across the Line

After eight years of effort, the 15 Asian members involved in the Regional Comprehensive Economic Partnership (RCEP) met in a virtual ceremony to sign the final document on Sunday, 15 November 2020. The final deal matches the original objective – to knit the region together and allow firms to build supply chains across the region to deliver goods, services, and investment to Asian markets more seamlessly. Getting this free trade agreement (FTA) to this point involved repeated missed deadlines, the loss of one important negotiating partner, and thousands of miles of travel for a rotating cast of officials, trade ministers, and leaders. RCEP began in late 2012 as an effort to unravel what has often been called the ‘spaghetti or noodle bowl’ of overlapping and inconsistent rules that can impede trade. While most of the countries in the region have extensive experience in trade and are outward oriented, trade in Asia has been bedeviled with challenges. This includes a range of both tariff and non-tariff obstacles that have made it more difficult than might be expected to trade, especially for final products, within the region.

A Novel Strategy for Optimal PSO Control Parameters Determination for PV Energy Systems

This study introduces a novel strategy that can determine the optimal values of control parameters of a PSO. These optimal control parameters will be very valuable to all the online optimization problems where the convergence time and the failure convergence rate are vital concerns. The newly proposed strategy uses two nested PSO (NESTPSO) searching loops; the inner one contained the original objective function, and the outer one used the inner PSO as a fitness function. The control parameters and the swarm size acted as the optimization variables for the outer loop. These variables were optimized for the lowest premature convergence rate, the lowest number of iterations, and the lowest swarm size. The new proposed strategy can be used for all the swarm optimization techniques as well. The results showed the superiority of the proposed NESTPSO control parameter determination when compared with several state of the art PSO strategies.

How at the Institute of Information Systems and Marketing One Thing Leads to Another and Eventually Results in a Low-Trade Theorem

This chapter portrays how research topics arise and develop in the creative environment of the research group Information & Market Engineering of the Institute of Information Systems and Marketing at the Karlsruhe Institute of Technology. It is somewhat long-winded in the beginning but identifies then a clear goal. In the following, it strays around several lines of research; touches on the question of why something like forecasting markets, the actual research topic, works at all – without answering it; and finally reaches a result that has little to do with the original objective. Along the way, the chapter provides some insights into the economic theory of double auctions.

La universidad en estado (a)crítico: entre la tecnocracia y la burocracia

The university, insofar as its main objective is the generation of knowledge, is constantly in a state of crisis. However, it is currently in an uncritical period regarding the power dynamics that have shaped its development in the last century. In this text, bureaucracy and technocracy are analyzed as control structures that determine the university in their own designs. From the acquisition of various functions outside its original objective, and from the transfer of legitimacy to other external bodies, the university has uncritically adopted an imposition of meaning that gradually leads to irrelevance. Only critical reflection and the unconditional search for truth can restore it to the central place it deserves in modern societies.

Digitization of US Herbaria - How close did we get to the 2020 goal?

A discussion session held at a National Science Foundation-sponsored Herbarium Networks Workshop at Michigan State University in September of 2004 resulted in a rallying objective: make all botanical specimen information in United States collections available online by 2020. Rabeler and Macklin 2006 outlined a toolkit for realizing this ambitious goal, which included: a review of relevant and state-of-the-art web resources, data exchange standards and, mechanisms to maximize efficiencies while minimizing costs. a review of relevant and state-of-the-art web resources, data exchange standards and, mechanisms to maximize efficiencies while minimizing costs. Given that we are now in the year 2020, it seems appropriate to examine the progress towards the objective of making all US botanical specimen collections data available online. Our presentation will attempt to answer several questions: How close have we come to meeting the original objective? What fraction of “digitized” specimens are minimally represented by a catalog number, a determination, and/or a photograph? What fraction has been thoroughly transcribed? How close have we come to attaining a seamlessly integrated, comprehensive, and national view of botanical specimen data that guides a stakeholder to appropriate resources regardless of their entry point? What “holes” in this effort still exist and what might be required to fill them? How close have we come to meeting the original objective? What fraction of “digitized” specimens are minimally represented by a catalog number, a determination, and/or a photograph? What fraction has been thoroughly transcribed? How close have we come to attaining a seamlessly integrated, comprehensive, and national view of botanical specimen data that guides a stakeholder to appropriate resources regardless of their entry point? What “holes” in this effort still exist and what might be required to fill them? Given our interest in the success of both the Global Biodiversity Information Facility (GBIF) and the Integrated Digitized Biocollections (iDigBio), as well as the overwhelming likelihood that either one of these initiatives is the usual entry point for someone seeking US-based botanical data, we approached the answers to the above questions by first crafting a repeatable data download and processing workflow in early July 2020. This resulted in 25.6M records of plant, fungi, and Chromista from 216 datasets available through GBIF and 32.8M comparable records available through iDigBio from 525 recordsets. We attempted to align these seemingly discordant sets of records and also chose Darwin Core terms that were best suited to match the four hierarchical levels of digitization defined in the Minimal Information for Digital Specimens (MIDS) (van Egmond et al. 2019). During the analysis/comparison of the datasets, we found several examples where the number of data records from an institution seemed much lower than expected. From a combination of analyzing record content in GBIF/iDigBio and consulting regional/taxonomic portals, it became evident that, besides datasets only being included in either GBIF or iDigBio, there was a significant number of records in regional/taxonomic portals that were not yet made available through either GBIF or iDigBio. Progress on digitization has benefited greatly from the US National Science Foundation's creation of the Advancing Digitization of Biodiversity Collections (ADBC) program, and funding of the 15 Thematic Collection Networks (TCN). The launching of new projects and the ensuing digitization of herbarium collections have led to a multitude of new specimen portals and the enhancement of existing software like Symbiota (Gries et al. 2014). But, it has also led to insufficient data sharing among projects and inadequately aligned data synchronization practices between aggregators. Consistency in terms of data availability and quality between GBIF and iDigBio is low, and the chronic lack of record-level identifiers consistently restricts the flow of enhancements made to records. We conclude that there remains substantial work to be done on the national infrastructure and on international best practices to help facilitate collaboration and to realize the original objective of making all US botanical specimen collections data available online.