Change-centric improvement of team collaboration

In software development, teamwork is essential to the successful delivery of a final product. The software industry has historically built software utilizing development teams that share the workplace. Process models, tools, and methodologies have been enhanced to support the development of software in a collocated setting. However, since the dawn of the 21st century, this scenario has begun to change: an increasing number of software companies are adopting global software development to cut costs and speed up the development process. Global software development introduces several challenges for the creation of quality software, from the adaptation of current methods, tools, techniques, etc., to new challenges imposed by the distributed setting, including physical and cultural distance between teams, communication problems, and coordination breakdowns. A particular challenge for distributed teams is the maintenance of a level of collaboration naturally present in collocated teams. Collaboration in this situation naturally d r ops due to low awareness of the activity of the team. Awareness is intrinsic to a collocated team, being obtained through human interaction such as informal conversation or meetings. For a distributed team, however, geographical distance and a subsequent lack of human interaction negatively impact this awareness. This dissertation focuses on the improvement of collaboration, especially within geographically dispersed teams. Our thesis is that by modeling the evolution of a software system in terms of fine-grained changes, we can produce a detailed history that may be leveraged to help developers collaborate. To validate this claim, we first c r eate a model to accurately represent the evolution of a system as sequences of fine- grained changes. We proceed to build a tool infrastructure able to capture and store fine-grained changes for both immediate and later use. Upon this foundation, we devise and evaluate a number of applications for our work with two distinct goals: 1. To assist developers with real-time information about the activity of the team. These applications aim to improve developers’ awareness of team member activity that can impact their work. We propose visualizations to notify developers of ongoing change activity, as well as a new technique for detecting and informing developers about potential emerging conflicts. 2. To help developers satisfy their needs for information related to the evolution of the software system. These applications aim to exploit the detailed change history generated by our approach in order to help developers find answers to questions arising during their work. To this end, we present two new measurements of code expertise, and a novel approach to replaying past changes according to user-defined criteria. We evaluate the approach and applications by adopting appropriate empirical methods for each case. A total of two case studies – one controlled experiment, and one qualitative user study – are reported. The results provide evidence that applications leveraging a fine-grained change history of a software system can effectively help developers collaborate in a distributed setting

Advanced information processing system: The Army fault tolerant architecture conceptual study. Volume 1: Army fault tolerant architecture overview

Digital computing systems needed for Army programs such as the Computer-Aided Low Altitude Helicopter Flight Program and the Armored Systems Modernization (ASM) vehicles may be characterized by high computational throughput and input/output bandwidth, hard real-time response, high reliability and availability, and maintainability, testability, and producibility requirements. In addition, such a system should be affordable to produce, procure, maintain, and upgrade. To address these needs, the Army Fault Tolerant Architecture (AFTA) is being designed and constructed under a three-year program comprised of a conceptual study, detailed design and fabrication, and demonstration and validation phases. Described here are the results of the conceptual study phase of the AFTA development. Given here is an introduction to the AFTA program, its objectives, and key elements of its technical approach. A format is designed for representing mission requirements in a manner suitable for first order AFTA sizing and analysis, followed by a discussion of the current state of mission requirements acquisition for the targeted Army missions. An overview is given of AFTA's architectural theory of operation

The evaluation of a breast cancer screening decision aid in the community setting.

Breast cancer screening (BCS) has been recommended to women by healthcare providers as well as professional organizations and non-profit awareness organizations for over four decades. Recently, attention is being paid to quantification of the actual benefits and harms of BCS with mammography. The harms include overdiagnosis, overtreatment and mandate of mammography screening that may not be in alignment with the individual values and preferences of women ages 40-69. This evidence translation project developed a resource for practice that was evaluated by community participants for alignment with personal value and preference-based educational needs about BCS. This project piloted a clinical practice decision aid (DA), called My Personal Decision (MPD), directly to a community-based convenience sample of women ages 40-69. Through a small sample of women, a change in knowledge about the harms and benefits of BCS was demonstrated. Evaluation feedback from the participants before and after use of the tool confirmed that MPD was helpful and enhanced preparedness for BCS decision-making. Provision of evidence-based information directly to women in the community setting was well received and perceived as valuable in the screening decision-making process in this context. Understanding of evidence-based information is a fundamental element in the empowerment of the decision maker with the goal of informed decision-making

Nurturing Systems Thinking: Developing a Framework Based on the Human Factors Analysis and Classification System (HFACS) to Improve Systems Development Processes

Large systems engineering projects have an astonishingly high failure rate. The reasons hypothesized for such a high failure rate include the neglect of nonsalient system elements such as social and human or organizational aspects of systems. Social and human factors have long been known to be critical elements of systems that are frequently ignored (e.g., Goguen, 1994). Systems engineering processes can benefit and be improved by effective utilization of a framework that helps developers expand their attention and efforts beyond the salient aspects of the system and the development process. In the aviation field, the Human Factors Analysis and Classification System (HFACS) is used to facilitate the consideration of non-salient, easily overlooked influences on the potential for aviation mishaps. This system has improved the effectiveness of the aviation accident investigation by helping investigators perform a thorough analysis of the system factors that may have contributed to the accident. HFACS helps aviation organizations improve their quality assessment and monitoring by making explicit the relationships between a wide range of organizational factors and accident risks. In this research, a framework similar to HFACS was developed for the systems engineering domain.The purpose of the framework is to guide and improve systems engineering projects. This research was conducted using qualitative methods to identify the elements and structure of a framework for quality improvement in system engineering. Data extracted from interviews and systems engineering literature was assessed in a bottom-up manner to identify emergent patterns and in a top-down manner using HFACS-based themes. The framework developed from this research can be used to guide systems development organizations analyze both the obvious and the latent reasons behind a project\u27s failure. This would help systems development teams to better understand the causal factors underlying a systems development failure and look out for them in the future. Using the framework, organizations and development teams can better understand the positive effects of considering all elements of a system, including the social and human factors that may not be obvious

Contributions to the routing of traffic flows in multi-hop IEEE 802.11 wireless networks

The IEEE 802.11 standard was not initially designed to provide multi-hop capabilities. Therefore, providing a proper traffic performance in Multi-Hop IEEE 802.11 Wireless Networks (MIWNs) becomes a significant challenge. The approach followed in this thesis has been focused on the routing layer in order to obtain applicable solutions not dependent on a specific hardware or driver. Nevertheless, as is the case of most of the research on this field, a cross-layer design has been adopted. Therefore, one of the first tasks of this work was devoted to the study of the phenomena which affect the performance of the flows in MIWNs. Different estimation methodologies and models are presented and analyzed. The first main contribution of this thesis is related to route creation procedures. First, FB-AODV is introduced, which creates routes and forwards packets according to the flows on the contrary to basic AODV which is destination-based. This enhancement permits to balance the load through the network and gives a finer granularity in the control and monitoring of the flows. Results showed that it clearly benefits the performance of the flows. Secondly, a novel routing metric called Weighted Contention and Interference routing Metric (WCIM) is presented. In all analyzed scenarios, WCIM outperformed the other analyzed state-of-the-art routing metrics due to a proper leveraging of the number of hops, the link quality and the suffered contention and interference. The second main contribution of this thesis is focused on route maintenance. Generally, route recovery procedures are devoted to the detection of link breaks due to mobility or fading. However, other phenomena like the arrival of new flows can degrade the performance of active flows. DEMON, which is designed as an enhancement of FB-AODV, allows the preemptive recovery of degraded routes by passively monitoring the performance of active flows. Results showed that DEMON obtains similar or better results than other published solutions in mobile scenarios, while it clearly outperforms the performance of default AODV under congestion Finally, the last chapter of this thesis deals with channel assignment in multi-radio solutions. The main challenge of this research area relies on the circular relationship between channel assignment and routing; channel assignment determines the routes that can be created, while the created routes decide the real channel diversity of the network and the level of interference between the links. Therefore, proposals which join routing and channel assignment are generally complex, centralized and based on traffic patterns, limiting their practical implementation. On the contrary, the mechanisms presented in this thesis are distributed and readily applicable. First, the Interference-based Dynamic Channel Assignment (IDCA) algorithm is introduced. IDCA is a distributed and dynamic channel assignment based on the interference caused by active flows which uses a common channel in order to assure connectivity. In general, IDCA leads to an interesting trade-off between connectivity preservation and channel diversity. Secondly, MR-DEMON is introduced as way of joining channel assignment and route maintenance. As DEMON, MR-DEMON monitors the performance of the active flows traversing the links, but, instead of alerting the source when noticing degradation, it permits reallocating the flows to less interfered channels. Joining route recovery instead of route creation simplifies its application, since traffic patterns are not needed and channel reassignments can be locally decided. The evaluation of MR-DEMON proved that it clearly benefits the performance of IDCA. Also, it improves DEMON functionality by decreasing the number of route recoveries from the source, leading to a lower overhead.El estándar IEEE 802.11 no fue diseñado inicialmente para soportar capacidades multi-salto. Debido a ello, proveer unas prestaciones adecuadas a los flujos de tráfico que atraviesan redes inalámbricas multi-salto IEEE 802.11 supone un reto significativo. La investigación desarrollada en esta tesis se ha centrado en la capa de encaminamiento con el objetivo de obtener soluciones aplicables y no dependientes de un hardware específico. Sin embargo, debido al gran impacto de fenómenos y parámetros relacionados con las capas físicas y de acceso al medio sobre las prestaciones de los tráficos de datos, se han adoptado soluciones de tipo cross-layer. Es por ello que las primeras tareas de la investigación, presentadas en los capítulos iniciales, se dedicaron al estudio y caracterización de estos fenómenos. La primera contribución principal de esta tesis se centra en mecanismos relacionados con la creación de las rutas. Primero, se introduce una mejora del protocolo AODV, que permite crear rutas y encaminar paquetes en base a los flujos de datos, en lugar de en base a los destinos como se da en el caso básico. Esto permite balacear la carga de la red y otorga un mayor control sobre los flujos activos y sus prestaciones, mejorando el rendimiento general de la red. Seguidamente, se presenta una métrica de encaminamiento sensible a la interferencia de la red y la calidad de los enlaces. Los resultados analizados, basados en la simulación de diferentes escenarios, demuestran que mejora significativamente las prestaciones de otras métricas del estado del arte. La segunda contribución está relacionada con el mantenimiento de las rutas activas. Generalmente, los mecanismos de mantenimiento se centran principalmente en la detección de enlaces rotos debido a la movilidad de los nodos o a la propagación inalámbrica. Sin embargo, otros fenómenos como la interferencia y congestión provocada por la llegada de nuevos flujos pueden degradar de forma significativa las prestaciones de los tráficos activos. En base a ello, se diseña un mecanismo de mantenimiento preventivo de rutas, que monitoriza las prestaciones de los flujos activos y permite su reencaminamiento en caso de detectar rutas degradadas. La evaluación de esta solución muestra una mejora significativa sobre el mantenimiento de rutas básico en escenarios congestionados, mientras que en escenarios con nodos móviles obtiene resultados similares o puntualmente mejores que otros mecanismos preventivos diseñados específicamente para casos con movilidad. Finalmente, el último capítulo de la tesis se centra en la asignación de canales en entornos multi-canal y multi-radio con el objetivo de minimizar la interferencia entre flujos activos. El reto principal en este campo es la dependencia circular que se da entre la asignación de canales y la creación de rutas: la asignación de canales determina los enlaces existentes la red y por ello las rutas que se podrán crear, pero son finalmente las rutas y los tráficos activos quienes determinan el nivel real de interferencia que se dará en la red. Es por ello que las soluciones que proponen unificar la asignación de canales y el encaminamiento de tráficos son generalmente complejas, centralizadas y basadas en patrones de tráfico, lo que limita su implementación en entornos reales. En cambio, en nuestro caso adoptamos una solución distribuida y con mayor aplicabilidad. Primero, se define un algoritmo de selección de canales dinámico basado en la interferencia de los flujos activos, que utiliza un canal común en todos los nodos para asegurar la conectividad de la red. A continuación, se introduce un mecanismo que unifica la asignación de canales con el mantenimiento preventivo de las rutas, permitiendo reasignar flujos degradados a otros canales disponibles en lugar de reencaminarlos completamente. Ambas soluciones demuestran ser beneficiosas en este tipo de entornos.Postprint (published version

Chronic Kidney Disease Patients\u27 Experiences in the Decision Making Process: The Relationship Between Personal Characteristics and Decisional Self-Efficacy on Decisional Conflict and the Dialysis Decision in Patients who Participated in Shared Decision Making

Patients with End Stage Renal Disease (ESRD) experience a complex and stressful decision making when comes to dialysis modality selection. There are pros and cons to both hemodialysis (HD) and peritoneal dialysis (PD). Patients are often uncertain as to which one is the best modality for them. This decisional conflict increases the likelihood of making a decision that is not based on the patient’s values or preferences and may result in undesirable post-decisional consequences. Purpose The purpose of this study was to explore Chronic Kidney Diseases (CKD) patients\u27 experiences regarding their decision making process in selecting a dialysis modality. The study examined individual characteristics and explores the relationship between characteristics such as demographics, decisional self-efficacy, and decisional conflict on perceived participation in shared decision making in a sample of individuals with CKD. Research Objective The objective of this mixed-method study was twofold: (a) to provide a quantitative description of the sample of individuals with CKD who are currently considering any one of the treatment strategies or currently receiving treatment for CKD within the last three months of diagnosis; and (b) to explore relationships between individual characteristics and participation in shared decision making (SDM) as they predict their decisional conflict and satisfaction with the decision made. Method This study employed a mixed-methods approach with an exploratory and a descriptive correlation designed to evaluate constructs of individual characteristics that may impact the decisions of individuals with CKD participating in shared decision making as described by the Ottawa Decisional Support Framework. Sample Study participants were recruited directly from the Kidney Solutions website (kidneysolutions.org). A recruitment flyer was sent out with the researcher’s contact information to Kidney Solutions along with the survey questionnaire using Google Forms. Kidney Solutions then sent out the link directly to all the patients who qualify for the study based on the inclusion criteria via email. No participants were contacted directly by the researcher. Participants were informed that their participation was voluntary, confidential, and that they could opt-out at any time. Procedure Data were collected after obtaining approval from Molloy College IRB. The survey was integrated into a single web-based set of questions using Google Forms. Completing the questionnaire indicated the subject\u27s consent to participate. The online survey included four inclusion criteria questions: (a) 18 years of age and older; (b) individuals who self-identify as having CKD diagnosed by a healthcare provider; (c) individuals currently considering or within the last three months has decided on a treatment option for CKD; (d) individuals who can participate in English and have modest internet skills. Measures Suitable tools were selected after an intense literature review that would be useful in measuring the research concepts in shared decision making, and permission was obtained from the developers of the tool for the study. These instruments capture participants’ self-reported Decisional Self-Efficacy Scale (DSES), decisional conflict (SURE test), shared decision making (9-item Shared Decision Making Questionnaire), and Satisfaction with Decision Instrument. Results Statistical analysis was performed to determine relationships between individual characteristics and concepts in shared decision making using t test, Chi-square, ANOVA and Pearson product-moment correlation coefficient and multiple linear regression. Participants were predominantly White (63.6%), male (54.5%), between 45-64 years old (45.5%), married or partnered (54.5%), college educated (60.0%), with most reporting CKD stage 5 (63.6%). There was a statistically significant difference at the p \u3c .05 level in SDMQ9 scores for Decision making support (t = -2.582, p \u3c .05) and use of a decisional aid in decision making (t = -2.357, p \u3c .05). The study also found a statistically significant association between current treatment option (p = .021) and decisional conflict as measured by the SURE test. There was a statistically significant positive correlation between decisional self-efficacy (as measured by the DSES) and shared decision making (as measured by the 9-item Shared Decision Making Questionnaire) observed (r = .390, n = 55, p \u3c .01). There was a significant relationship between participation in shared decision making and decisional conflict (r = -0.362, p \u3c .01). The results indicated a negative correlation, which means as SDM increases, less decisional conflict is reported by the participants. There was a significant relationship between decisional self-efficacy and decisional conflict (r = -0.489, p \u3c .001). The results indicated a negative correlation, which means as Decisional Self-Efficacy increases, less decisional conflict is reported by the participants. There was also a positive correlation between shared decision making and satisfaction with the decision, r = .701, n = 55, p \u3c .01. There was also a positive correlation between decisional self-efficacy and satisfaction with decision, r = .624, n = 55, p \u3c .01. Prediction for satisfaction with decision (SWD) is significant using a multiple linear regression model by combining decisional self-efficacy (DSES) and SDM, with n = 55, R = 0.797, R square 0.636, Adjusted R square = 0.622, F = 45.408. Prediction for decisional conflict (SURE) was significant using a multiple linear regression model by combining DSES and SDM, with n = 55, R = 0.523, R square 0.273, Adjusted R square = 0.245, F = 9.781. In this model, decisional self-efficacy predicts decisional conflict more than shared decision making. Shared decision making had a non-significant impact on the dependent variable decisional conflict alone, but it adds to the prediction when combined with decisional self-efficacy. Qualitative findings supported several quantitative findings, adding depth to understanding participants’ views. Conclusions The findings contribute to understanding the importance of increasing patient involvement in determining treatment when more than one treatment option exists based on the goals of care. Providers must approach their patients’ critical decision points in their illness trajectory with an openness of sharing in the plan of care. There is a significant need to move away from a “one-size-fits-all” approach to dialysis and provide more individualized care that incorporates patient goals and preferences while still maintaining best practices for quality and safety