A Case Study on Formal Verification of Self-Adaptive Behaviors in a Decentralized System

Self-adaptation is a promising approach to manage the complexity of modern software systems. A self-adaptive system is able to adapt autonomously to internal dynamics and changing conditions in the environment to achieve particular quality goals. Our particular interest is in decentralized self-adaptive systems, in which central control of adaptation is not an option. One important challenge in self-adaptive systems, in particular those with decentralized control of adaptation, is to provide guarantees about the intended runtime qualities. In this paper, we present a case study in which we use model checking to verify behavioral properties of a decentralized self-adaptive system. Concretely, we contribute with a formalized architecture model of a decentralized traffic monitoring system and prove a number of self-adaptation properties for flexibility and robustness. To model the main processes in the system we use timed automata, and for the specification of the required properties we use timed computation tree logic. We use the Uppaal tool to specify the system and verify the flexibility and robustness properties.Comment: In Proceedings FOCLASA 2012, arXiv:1208.432

Cultural Transformation in Health Care

Describes the role of organizational culture in healthcare organizations. Recommends strategies for innovative approaches to improve the overall performance of the U.S. healthcare system

Towards a Formal Model of Recursive Self-Reflection

Self-awareness holds the promise of better decision making based on a comprehensive assessment of a system\u27s own situation. Therefore it has been studied for more than ten years in a range of settings and applications. However, in the literature the term has been used in a variety of meanings and today there is no consensus on what features and properties it should include. In fact, researchers disagree on the relative benefits of a self-aware system compared to one that is very similar but lacks self-awareness. We sketch a formal model, and thus a formal definition, of self-awareness. The model is based on dynamic dataflow semantics and includes self-assessment, a simulation and an abstraction as facilitating techniques, which are modeled by spawning new dataflow actors in the system. Most importantly, it has a method to focus on any of its parts to make it a subject of analysis by applying abstraction, self-assessment and simulation. In particular, it can apply this process to itself, which we call recursive self-reflection. There is no arbitrary limit to this self-scrutiny except resource constraints

Organization of Multi-Agent Systems: An Overview

In complex, open, and heterogeneous environments, agents must be able to reorganize towards the most appropriate organizations to adapt unpredictable environment changes within Multi-Agent Systems (MAS). Types of reorganization can be seen from two different levels. The individual agents level (micro-level) in which an agent changes its behaviors and interactions with other agents to adapt its local environment. And the organizational level (macro-level) in which the whole system changes it structure by adding or removing agents. This chapter is dedicated to overview different aspects of what is called MAS Organization including its motivations, paradigms, models, and techniques adopted for statically or dynamically organizing agents in MAS.Comment: 12 page

Principles of Antifragile Software

The goal of this paper is to study and define the concept of "antifragile software". For this, I start from Taleb's statement that antifragile systems love errors, and discuss whether traditional software dependability fits into this class. The answer is somewhat negative, although adaptive fault tolerance is antifragile: the system learns something when an error happens, and always imrpoves. Automatic runtime bug fixing is changing the code in response to errors, fault injection in production means injecting errors in business critical software. I claim that both correspond to antifragility. Finally, I hypothesize that antifragile development processes are better at producing antifragile software systems.Comment: see https://refuses.github.io

Arts, Health and Well-Being across the Military Continuum

Is there an active, meaningful role for the arts and creative arts therapies in addressing this vast array of critical human readiness issues across the military continuum? In general, "readiness" is the #1 issue for the military at all times. The connection of the arts to the human dimension of readiness is key. Military leaders say we need every weapon in our arsenal to meet the many challenges we face today. However, one of the most powerful tools we have in our arsenal -- the arts -- is often under-utilized and not well understood within the military and the healthcare system. The arts and creative arts therapists are -- and have been -- a part of military tradition and missions across all branches, supporting military health services, wellness, and mission readiness, including family support. For example, the War Department ordered the use of music in rehabilitation for the war wounded in World War II. In June 1945, the Department of War issued "Technical Bulletin 187: Music in Reconditioning in American Service Convalescent and General Hospitals." This bulletin was a catalyst for the growth and development of music therapy being used as a rehabilitative service for active duty service members and veterans alike during and after WWII. Although many gaps exist in our knowledge regarding the arts in military settings, what we do know to date holds great promise for powerful outcomes for our service members, veterans, their families, and the individuals who care for them. Today, a growing number of members of the public and private sectors are eager to collaborate with military leaders to help make these outcomes a reality.Nowhere was the momentum for greater collaboration more evident than in October 2011, when the first National Summit: Arts in Healing for Warriors was held at Walter Reed National Military Medical Center (now referred to as Walter Reed Bethesda) and the National Intrepid Center of Excellence (NICoE). Rear Admiral Alton L. Stocks, Commander of Walter Reed Bethesda, hosted the National Summit, in partnership with a national planning group of military, government, and nonprofit leaders. The 2011 Summit marked the first time various branches of the military collaborated with civilian agencies to discuss how engaging with the arts provides opportunities to meet the key health issues our military faces -- from pre-deployment to deployment to homecoming.Building upon its success, a multi-year National Initiative for Arts & Health in the Military was established in 2012, with the advice and guidance of federal agency, military, nonprofit, and private sector partners (see Figure 2). The National Initiative for Arts & Health in the Military (National Initiative) represents an unprecedented military/civilian collaborative effort whose mission is to "advance the arts in health, healing, and healthcare for military service members, veterans, their families, and caregivers."Members of the National Initiative share a commitment to optimize health and wellness, with a deep understanding and awareness that the arts offer a unique and powerful doorway into healing in ways that many conventional medical approaches do not. The Initiative's goals include working across military, government, private, and nonprofit sectors to: 1. Advance the policy, practice, and quality use of arts and creativity as tools for health in the military; 2. Raise visibility, understanding, and support of arts and health in the military; and 3. Make the arts as tools for health available to all active duty military, medical staff, family members, and veterans

Preparing For the Crossfire: Equipping Evangelical Leaders for Service in Public Schools

This article addresses the preparation and support needed by evangelicals who serve as administrators and teacher leaders in public school settings. Educational leadership is lonely, demanding, and draining. This article explores the unique challenges evangelical leaders face because of the ongoing conflict between conservative Christians and public schools. Work-related conflicts that evangelicals experience in the workplace due to faith and the cultural dynamics that fuel this conflict are described. Strategies are proposed for Christian colleges and universities to prepare school leaders for the cultural crossfire

HiTrust: building cross-organizational trust relationship based on a hybrid negotiation tree

Small-world phenomena have been observed in existing peer-to-peer (P2P) networks which has proved useful in the design of P2P file-sharing systems. Most studies of constructing small world behaviours on P2P are based on the concept of clustering peer nodes into groups, communities, or clusters. However, managing additional multilayer topology increases maintenance overhead, especially in highly dynamic environments. In this paper, we present Social-like P2P systems (Social-P2Ps) for object discovery by self-managing P2P topology with human tactics in social networks. In Social-P2Ps, queries are routed intelligently even with limited cached knowledge and node connections. Unlike community-based P2P file-sharing systems, we do not intend to create and maintain peer groups or communities consciously. In contrast, each node connects to other peer nodes with the same interests spontaneously by the result of daily searches

Size Matters: Microservices Research and Applications

In this chapter we offer an overview of microservices providing the introductory information that a reader should know before continuing reading this book. We introduce the idea of microservices and we discuss some of the current research challenges and real-life software applications where the microservice paradigm play a key role. We have identified a set of areas where both researcher and developer can propose new ideas and technical solutions.Comment: arXiv admin note: text overlap with arXiv:1706.0735