Understanding Open Source Communities as Complex Adaptive Systems: A Case of the R Project Community

Open source communities evolve. This evolution is, at times, driven by corporate engagement with those communities. In these corporate-communal contexts, open source foundations often serve as facilitators in the evolution process and make these arrangements more stable over time. This paper expands the application of complex adaptive systems (CAS) theory to understand the role of open source foundations as facilitators in the evolution of corporate-communal arrangements. We present the case of the R Project community and how we can leverage complex adaptive systems as a way to understand the evolution of the community as driven by corporate engagement and facilitated by open source foundations. We develop the theory of CAS by enhancing the understanding of attractors in the evolution of CAS

Anxiety, depressed mood, self-esteem, and traumatic stress symptoms among distant witnesses of the 9/11 terrorist attacks: transitory responses and psychological resilience

Posttraumatic stress related to the September 11, 2001 terrorist attacks and general psychological distress were examined in six cohorts of college students (N=5,412) enrolled at an American public university between Spring 2000 and Fall 2002 some 2,500 miles from New York. Consistent with data from Schuster et al.’s (2001) national survey, which used a very low threshold criterion, our findings revealed that 44% of women and 32% of men experienced at least one symptom of posttraumatic stress 6-17 days after the attacks. In contrast to these results, depression levels showed only small differences, and self-esteem and trait anxiety showed no changes. Findings indicate that 9/11-related stress responses among distant witnesses were very mild, transitory and focused in scope, suggesting resilience with respect to broader psychological and psychopathological reactions. Findings are discussed with respect to the role of physical and psychological proximity on the reactions to traumatic events in the general population.El estrés post-traumático relacionado con los atentados terroristas del 11 de septiembre de 2001, así como el malestar psicológico general se examinaron en seis cohortes de estudiantes universitarios (N=5.412) matriculados entre la primavera de 2000 y el otoño de 2002 en una universidad pública norteamericana distante 2.500 millas aproximadamente de Nueva York De modo consistente con los datos del estudio a nivel nacional de Schuster et al. (2001), donde se empleó un criterio de corte muy bajo, nuestros resultados fueron que el 44% de las mujeres y el 32% de los hombres experimentaron al menos un síntoma de estrés post-traumático entre 6-17 días después de los atentados. En contraste con estos resultados, los niveles de depresión mostraron únicamente pequeñas diferencias y en la autoestima y la ansiedad de rasgo no se encontró cambio alguno. Nuestros hallazgos indican que, entre testigos distantes, las respuestas de estrés relacionadas con el 11/9 fueron muy débiles, transitorias y de alcance limitado, lo que sugiere resiliencia en lo referido a las reacciones psicológicas y psicopatológicas Estos hallazgos se discuten en relación con los efectos de la proximidad física y psicológica sobre las reacciones a hechos traumáticos en la población general

Post-Traumatic Stress Reactions Following the March 11, 2004 Terrorist Attacks in a Madrid Community Sample: A Cautionary Note about the Measurement of Psychological Trauma

Posttraumatic stress reactions related to the Madrid March 11, 2004, terrorist attacks were examined in a sample of Madrid residents (N = 503) 18-25 days after the attacks, using multiple diagnostic criteria and different cut-off scores. Based on the symptoms covered by the Posttraumatic Stress Disorder Checklist-Civilian (PCL-C; Weathers, Litz, Herman, Huska, & Keane, 1993), rates of probable posttraumatic stress disorder (PTSD) ranged from 3.4% to 13.3%. Taking into account additional criteria from the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 200; i.e., the impact of initial reaction and problems in daily functioning as a consequence of the traumatic event), only 1.9% of respondents reported probable PTSD. These results suggest that inferences about the impact of traumatic events on the general population are strongly influenced by the definition of traumatic response. Our findings also revealed that the magnitude of posttraumatic reactions is associated with several risk factors, including living close to the attacked locations, physical proximity to the attacks when they occurred, perception of one’s life being at risk, intensity of initial emotional reactions, and being a daily user of the attacked train lines. The use of different cut-off scores did not affect the pattern of risk to develop traumatic stress. The implications of these results for public health policies related to terrorist attacks are discussed.Se examinaron reacciones de estrés postraumático, empleando múltiples criterios diagnósticos y puntos de corte, en una muestra de la población de Madrid (N = 503), 18-25 días después de los ataques terroristas de Madrid del 11 de marzo de 2004. En función del punto de corte seleccionado, los porcentajes de probable trastorno de estrés postraumático (TEPT) basado en el Posttraumatic Stress Disorder Checklist-Civilian (PCL-C; Weathers, Litz, Herman, Huska, & Keane, 1993) fluctuaban entre el 3,4% y el 13,3%. Al añadir a los síntomas de TEPT otros criterios del Manual Diagnóstico y Estadístico de Trastornos Mentales (American Psychiatric Association, 2000) requeridos para su diagnóstico (p. ej., el impacto de la reacción inicial y problemas en el funcionamiento cotidiano como consecuencia del evento traumático), sólo el 1,9% presentaba un probable TEPT. Estos resultados demuestran que las inferencias acerca del impacto de eventos traumáticos en la población general pueden depender en gran parte de la definición y medida de la respuesta traumática. Nuestros resultados también revelaron que, aunque la magnitud de las reacciones postraumáticas se relacionaba con varios factores de riesgo (vivir cerca de los lugares atacados, proximidad física a los ataques cuando ocurrieron, percepción de amenaza para la propia vida, intensidad de las reacciones emocionales iniciales, y ser un usuario diario de las líneas de trenes atacadas), el uso de diferentes estrategias de punto de corte no afectó el patrón principal de riesgo para el desarrollo de estrés traumático. Se comentan las implicaciones de estos resultados para las políticas de la salud pública relacionadas con los ataques terroristas

Nicotine on Children's Hands: Limited Protection of Smoking Bans and Initial Clinical Findings.

BackgroundThirdhand smoke (THS) pollutants, such as nicotine, accumulate on the hands of children who live in homes with smokers and are exposed to secondhand smoke. Our objective was to examine whether levels of hand nicotine in exposed children are associated with demographics, environmental factors, and clinical findings.MethodsParticipants were caregivers who smoke and children (mean age (SD) = 2.6 (3.7) years) who were part of an ongoing 2-group, randomized controlled trial of an emergency department-based tobacco cessation intervention (N = 104). The primary outcome measure was nicotine on the child's hand. Caregivers reported demographics and smoking patterns; children's medical records were abstracted for chief complaint, medical history, and diagnoses.ResultsAll children had detectable hand nicotine (geometric mean [GeoM] = 86.2 ng/wipe; range = 3.5-2, 190.4 ng/wipe). Children in the age group of 2 to 4 years old (GeoM = 185.6 ng/wipe) had higher levels than the children in the age groups of 0 to 1 (GeoM = 68.9 ng/wipe, P < .001), 5 to 9 (GeoM = 77.9 ng/wipe, P = .04), and 10 to 15 years old (GeoM = 74.2 ng/wipe, P = .048). Children whose caregivers smoked 6 to 14 (GeoM = 97.2 ng/wipe, P = .047) and 15 to 40 cigarettes/day (GeoM = 124.0 ng/wipe, P = .01) had higher levels than children whose caregivers smoked 1 to 5 cigarettes/day (GeoM = 59.7 ng/wipe). Children with 6 to 14 cigarettes/day (GeoM = 163.11 ng/wipe, P = .007) and 15 to 40 cigarettes/day (GeoM = 186.1, P = .003) smoked inside the home by all smokers had significantly higher levels than homes with 0 cigarettes (GeoM = 81.3 ng/wipe). Similar differences in hand nicotine levels were found for smoking frequency of all household members in any location. Children with complaints of cough/congestion (GeoM = 97.7 ng/wipe) had higher levels than those without cough/congestion (GeoM = 59.0 ng/wipe, P = .01).ConclusionsThe high hand nicotine levels in children whose caregivers do not necessarily smoke indoor demonstrate that indoor smoking bans do not safeguard against THS exposure and the associations with increased home smoking activity indicate that hand wipes may be a noninvasive way to characterize children's exposure. The findings of associated cough and congestion with higher THS levels need to be examined further

Open Data Standards for Open Source Software Risk Management Routines: An Examination of SPDX

As the organizational use of open source software (OSS) increases, it requires the adjustment of organizational routines to manage new OSS risk. These routines may be influenced by community-developed open data standards to explicate, analyze, and report OSS risks. Open data standards are co-created in open communities for unifying the exchange of information. The SPDX® specification is such an open data standard to explicate and share OSS risk information. The development and subsequent adoption of SPDX raises the questions of how organizations make sense of SPDX when improving their own risk management routines, and of how a community benefits from the experiential knowledge that is contributed back by organizational adopters. To explore these questions, we conducted a single case, multi-component field study, connecting with members of organizations that employed SPDX. The results of this study contribute to understanding the development and adoption of open data standards within open source environments

Eight Observations and 24 Research Questions About Open Source Projects: Illuminating New Realities

The rapid acceleration of corporate engagement with open source projects is drawing out new ways for CSCW researchers to consider the dynamics of these projects. Research must now consider the complex ecosystems within which open source projects are situated, including issues of for-profit motivations, brokering foundations, and corporate collaboration. Localized project considerations cannot reveal broader workings of an open source ecosystem, yet much empirical work is constrained to a local context. In response, we present eight observations from our eight-year engaged field study about the changing nature of open source projects. We ground these observations through 24 research questions that serve as primers to spark research ideas in this new reality of open source projects. This paper contributes to CSCW in social and crowd computing by delivering a rich and fresh look at corporately-engaged open source projects with a call for renewed focus and research into newly emergent areas of interest

A deployment-friendly decentralized scheduling approach for cooperative multi-agent systems in production systems

Abstract Decentralized control paradigms are becoming more and more attractive in an ever-changing commercial environment, where there is a strong trend towards smaller production lot sizes. Whereas centralized scheduling might find a global throughput optimum (even at high computational and implementation cost), decentralized scheduling decisions in a multi-agent system are much more manageable and agents are more robust to handle any interruptions that might take place on the production floor. Compared to a centralised architecture, the development, testing and commissioning is definitely more complex, as it requires the availability of the physical units. Yet these aspects are not visited frequently by research activities. This paper details a novel implementation approach of a multi-agent based production control, that was developed for a lab-contained production environment that serves as test-bed for decentralized scheduling algorithms, with both a nominal operational mode and a simulation mode. The latter one is introduced to ease up the deployment process of the system. The description of the new approach is illustrated with different examples

Stellarator coil optimization supporting multiple magnetic configurations

We present a technique that can be used to design stellarators with a high degree of experimental flexibility. For our purposes, flexibility is defined by the range of values the rotational transform can take on the magnetic axis of the vacuum field while maintaining satisfactory quasisymmetry. We show that accounting for configuration flexibility during the modular coil design improves flexibility beyond that attained by previous methods. Careful placement of planar control coils and the incorporation of an integrability objective enhance the quasisymmetry and nested flux surface volume of each configuration. We show that it is possible to achieve flexibility, quasisymmetry, and nested flux surface volume to reasonable degrees with a relatively simple coil set through an NCSX-like example. This preliminary coil design is optimized to achieve three rotational transform targets and nested flux surface volumes in each magnetic configuration larger than the NCSX design plasma volume. Our work suggests that there is a tradeoff between flexibility, quasisymmetry, and volume of nested flux surfaces

Single-stage gradient-based stellarator coil design: stochastic optimization

We extend the single-stage stellarator coil design approach for quasi-symmetry on axis from [Giuliani et al, 2020] to additionally take into account coil manufacturing errors. By modeling coil errors independently from the coil discretization, we have the flexibility to consider realistic forms of coil errors. The corresponding stochastic optimization problems are formulated using a risk-neutral approach and risk-averse approaches. We present an efficient, gradient-based descent algorithm which relies on analytical derivatives to solve these problems. In a comprehensive numerical study, we compare the coil designs resulting from deterministic and risk-neutral stochastic optimization and find that the risk-neutral formulation results in more robust configurations and reduces the number of local minima of the optimization problem. We also compare deterministic and risk-neutral approaches in terms of quasi-symmetry on and away from the magnetic axis, and in terms of the confinement of particles released close to the axis. Finally, we show that for the optimization problems we consider, a risk-averse objective using the Conditional Value-at-Risk leads to results which are similar to the risk-neutral objective