Towards a Rule-level Verification Framework for Property-Preserving Graph Transformations

International audienceWe report in this paper a method for proving that a graph transformation is property-preserving. Our approach uses a relational representation for graph grammar and a logical representation for graph properties with first-order logic formulas. The presented work consists in identifying the general conditions for a graph grammar to preserve graph properties, in particular structural properties. We aim to implement all the relevant notions of graph grammar in the Isabelle/HOL proof assistant in order to allow a (semi) automatic verification of graph transformation with a reasonable complexity. Given an input graph and a set of graph transformation rules, we can use mathematical induction strategies to verify statically if the transformation preserves a particular property of the initial graph. The main highlight of our approach is that such a verification is done without calculating the resulting graph and thus without using a transformation engine

Lattice-Based Cryptography for Privacy Preserving Machine Learning

The digitization of healthcare data has presented a pressing need to address privacy concerns within the realm of machine learning for healthcare institutions. One promising solution is Federated Learning (FL), which enables collaborative training of deep machine learning models among medical institutions by sharing model parameters instead of raw data. This study focuses on enhancing an existing privacy-preserving federated learning algorithm for medical data through the utilization of homomorphic encryption, building upon prior research. In contrast to the previous paper this work is based upon by Wibawa, using a single key for homomorphic encryption, our proposed solution is a practical implementation of a preprint by Ma Jing et. al. with a proposed encryption scheme (xMK-CKKS) for implementing multi-key homomorphic encryption. For this, our work first involves modifying a simple “ring learning with error” RLWE scheme. We then fork a popular FL framework for python where we integrate our own communication process with protocol buffers before we locate and modify the library’s existing training loop in order to further enhance the security of model updates with the multi-key homomorphic encryption scheme. Our experimental evaluations validate that despite these modifications, our proposed framework maintains robust model performance, as demonstrated by consistent metrics including validation accuracy, precision, f1-score, and recall

Construction and management of ethnicities in Southeast Asia : cultures, policies and development

Regional social sciences Summer university, "Tam Đáo Summer school week", Việt Nam, July 2011 ; [organized by École française d'Extrême-Orient ; Agence française de développement ; Institut de recherche pour le développement, et al.] ; [scientific editor, Stéphane Lagrée]GOODInternational audienceWelcome to the workshop on ethnic groups in Southeast Asia. We will start with introductions from the participants; this workshop is structured so as to promote the methodological and pedagogic dimension, and exchanges and discussions will be a priority all week. Presentation of the trainers and participants (see biographies of trainers and list of participants at the end of the chapter) How will these four and a half days of group work unfold? We will devote this first day to the ways in which ethnic groups are designated and named, and our approach will initially be theoretical and methodological: we will explain the constructivist and naturalist approaches. We will ask what an ethnic group is and how and why we make ethnic classifications. In the afternoon, we will turn towards case studies in Việt Nam and in Laos. Tuesday will be devoted to the relationship between the law and ethnic groups. We will start with the legal situation so as to be able to observe the relationship with what is visible in the field. Sociologists and anthropologists use the law very rarely as an instrument of knowledge; we will try to establish a relationship between law and anthropology. We will conclude this second day with case studies. Questions from applied anthropology and development anthropology will be studied on Wednesday morning, then we will together organize three working groups, one group per trainer with a specific theme. Friday morning will be devoted to presentations from each group; from these we will derive a synthesis for the public reporting session on Saturday

Forming Early-type Galaxies in Groups Prior to Cluster Assembly

We study a unique proto-cluster of galaxies, the supergroup SG1120-1202. We quantify the degree to which morphological transformation of cluster galaxies occurs prior to cluster assembly in order to explain the observed early-type fractions in galaxy clusters at z=0. SG1120-1202 at z~0.37 is comprised of four gravitationally bound groups that are expected to coalesce into a single cluster by z=0. Using HST ACS observations, we compare the morphological fractions of the supergroup galaxies to those found in a range of environments. We find that the morphological fractions of early-type galaxies (~60 %) and the ratio of S0 to elliptical galaxies (0.5) in SG1120-1202 are very similar to clusters at comparable redshift, consistent with pre-processing in the group environment playing the dominant role in establishing the observed early-type fraction in galaxy clusters.Comment: 5 pages, 2 figures, 2 tables. Accepted for publication in ApJ Letter

Combining active learning suggestions

We study the problem of combining active learning suggestions to identify informative training examples by empirically comparing methods on benchmark datasets. Many active learning heuristics for classification problems have been proposed to help us pick which instance to annotate next. But what is the optimal heuristic for a particular source of data? Motivated by the success of methods that combine predictors, we combine active learners with bandit algorithms and rank aggregation methods. We demonstrate that a combination of active learners outperforms passive learning in large benchmark datasets and removes the need to pick a particular active learner a priori. We discuss challenges to finding good rewards for bandit approaches and show that rank aggregation performs well.The research was supported by the Data to Decisions Cooperative Research Centre whose activities are funded by the Australian Commonwealth Government’s Cooperative Research Centres Programme. This research was supported by the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO), through project number CE110001020. The SDSS dataset was extracted from Data Release 12 of SDSS-III. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the U.S. Department of Energy Office of Science. The SDSS-III web site is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale Universit

A Precondition Calculus for Correct-by-Construction Graph Transformations

We aim at assisting developers to write, in a Hoare style, provably correct graph transformations expressed in the ALCQ Description Logic. Given a postcondition and a transformation rule, we compute the weakest precondition for developers. However, the size and quality of this formula may be complex and hard to grasp. We seek to reduce the weakest precondition’s complexness by a static analysis based on an alias calculus. The refined precondition is presented to the developer in terms of alternative formulae, each one specifying a potential matching of the source graph. The developer chooses then the formulae that correspond to his intention to obtain finally a correct-byconstruction Hoare triple

SLRefactor: Ein Refactoring-Ansatz für Simulink-Modelle

Bei der Funktionsmodellierung ist die Veränderung und Erweiterung der Struktur eines Modells eine häufig durchgeführte Aktivität. Während es bereits Refactoring-Ansätze für textuelle Programmiersprachen wie Java, C# usw. gibt, fehlt ein vergleichbarer, integraler und durchgehender Ansatz für Simulink-Modelle. Wir haben einen automatisierten Refactoring-Ansatz (im Folgenden SLRefactor-Ansatz genannt) für Simulink-Modelle erfolgreich entwickelt, der in einem Zeitraum von ca. zwei Jahren in der Serienentwicklung bei der Daimler AG erprobt und eingesetzt wurde. In diesem Beitrag wird der SLRefactor-Ansatz anhand eines ausführlichen Beispiels erläutert und es wird über die Erfahrungen beim produktiven Einsatz des Ansatzes und über die dabei gewonnenen Erkenntnisse berichtet

No One Walks Alone: Fall Prevention Program

Background: Hospitals strive for patient safety, with fall prevention being a top priority. To improve patient safety outcomes, two local hospitals implemented No One Walks Alone (NOWA), an innovative fall prevention program. Purpose: The purpose of this study was to determine the effectiveness of the NOWA at Hospital A and Hospital B. The study continues to be part of a national system-wide implementation of NOWA. Methods: All staff were trained in the NOWA program. Hospital A implemented the program March 3, 2014 and Hospital B began implementation on two units on March 18, 2014. Data was collected by monitoring fall rates over a one-month trial period. Results: Data showed a decrease in falls at both hospitals after implementation of NOWA. Discussion/Recommendation: The study was limited to one month of data. Long-term data is needed to better evaluate the effectiveness of the program in both hospitals. Topics that need to be discussed and addressed are patient refusal rates and modified plans for specialty units. Further data analysis can help identify the most effective methods in preventing falls. Hospital B should begin implementation hospital-wide

A Practical Implementation of Medical Privacy-Preserving Federated Learning Using Multi-Key Homomorphic Encryption and Flower Framework

The digitization of healthcare data has presented a pressing need to address privacy concerns within the realm of machine learning for healthcare institutions. One promising solution is federated learning, which enables collaborative training of deep machine learning models among medical institutions by sharing model parameters instead of raw data. This study focuses on enhancing an existing privacy-preserving federated learning algorithm for medical data through the utilization of homomorphic encryption, building upon prior research. In contrast to the previous paper, this work is based upon Wibawa, using a single key for HE, our proposed solution is a practical implementation of a preprint with a proposed encryption scheme (xMK-CKKS) for implementing multi-key homomorphic encryption. For this, our work first involves modifying a simple “ring learning with error” RLWE scheme. We then fork a popular federated learning framework for Python where we integrate our own communication process with protocol buffers before we locate and modify the library’s existing training loop in order to further enhance the security of model updates with the multi-key homomorphic encryption scheme. Our experimental evaluations validate that, despite these modifications, our proposed framework maintains a robust model performance, as demonstrated by consistent metrics including validation accuracy, precision, f1-score, and recall.publishedVersio

Incidence of dengue and chikungunya viruses in mosquitoes and human patients in border provinces of Vietnam

Background: Dengue virus remains a major threat in Vietnam, while chikungunya virus is expected to become one. Surveillance was conducted from 2012 to 2014 in Vietnam to assess the presence of dengue and chikungunya viruses in patients hospitalized with acute fever in five Vietnam provinces neighboring Lao PDR and Cambodia. Surveillance was extended to mosquitoes present in the vicinity of the patients' households. Results: A total 558 human serum samples were collected along with 1104 adult mosquitoes and 12,041 larvae from 2250 households. Dengue virus was found in 17 (3%) human serum samples and in 9 (0.8%) adult mosquitoes. Chikungunya virus was detected in 2 adult mosquitoes (0.18%) while no chikungunya virus was detected in humans. Differing densities of mosquito populations were found, with the highest in the Long An Province border with Cambodia. Long An Province also displayed the lowest rate of infection, despite a very high Breteau Index, high human population density and presence of the main cross border road system. The highest incidence was found in Dac Nong Province, where the Breteau and Container indices were the second lowest. Dengue virus was detected in five Aedes albopictus, three Aedes aegypti and one Culex vishnui. Chikungunya virus was detected in two Ae. aegypti. All infected mosquitoes belonged to haplotypes described in other parts of the world and a number of novel haplotypes were found among uninfected mosquitoes. Conclusions: Dengue is considered to be regularly introduced to Vietnam from Cambodia, mostly through human movement. The data reported here provides a complementary picture. Due to intensive international trade, long-distance transportation of mosquito populations may play a role in the regular importation of dengue in Vietnam through Ho Chi Minh City. It is important to decipher the movement of mosquitoes in Vietnam, not only at the Lao PDR and Cambodia borders but also through international trade routes. Mosquito surveillance programs should address and follow mosquito populations instead of mosquito species