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Shared Space är ett koncept som syftar till att integrera fotgängare, cyklister och bilister på en gemensam yta och beskrivs ofta som ett koncept som bidrar till ökad trafiksäkerhet och attraktiva stadsrum. Begreppet attraktiva stadsrum innefattar ett flertal olika aspekter; trivsamma platser där människor vill vistas, tillgänglighet, trygghet och trafiksäkerhet.Denna studie baseras på en jämförelse av tre gatutyper i Malmö. Observationer, intervjuer och olycksstatistik varvas med teori för att på så sätt kunna utvärdera huruvida Shared Space, utifrån exemplet Kalendegatan, kan tillskrivas de kvaliteter som inryms i begreppet attraktiva stadsrum. Stort fokus ligger på de intervjuer som genomförts med trafikanterna och på deras upplevelser av de olika stadsrummen.Resultatet av studien visar på att Shared Space, genom exemplet Kalendegatan, upplevs och fungerar som en trafiksäker miljö, men är bristfällig utifrån kvaliteterna trygghet, tillgänglighet och attraktivitet. Resultatet tyder också på att cyklister är en användargrupp som ofta glöms bort i och med implementeringen av Shared Space, då dessa är i behov av en egen bana för att framkomlighet och trygghet ska främjas på bästa möjliga sätt.Med denna studie vill vi klargöra hur Shared Space upplevs och fungerar utifrån ett användarperspektiv som inkluderar både fotgängare, cyklister och bilister, samt hur Shared Space, utifrån exemplet Kalendegatan, fungerar med hänseende till trygghet, tillgänglighet, attraktivitet och trafiksäkerhet. / Shared Space is a concept that aims to integrate pedestrians, cyclists and motorists on a common surface and is often described as an approach to help improve road safety and attractive urban spaces. An attractive urban space involves several different aspects; places for social activity, availability, security and traffic safety.This study is based on a comparison of three different street types in Malmö. Observations, interviews and accident statistics is interspersed with theory in order to be able to evaluate whether Shared Space, based on the example Kalendegatan, can ascribe to the qualities embodied in the concept of attractive urban spaces. The main focus lies on the interviews conducted with the users and principally on their perceptions of the various urban spaces.The results of the study indicate that Shared Space serves as a safe traffic environment, but is inadequate based on the qualities of security, accessibility and attractiveness. The results also suggest that cyclists often are neglected in the implementation of Shared Space, as they are in need of their own path in order to encourage mobility and security in the best possible way.With this study we want to clarify how Shared Space is perceived from a user perspective, including both pedestrians, cyclists and motorists, and how Shared Space, based on the example Kalendegatan, functions with respect to security, accessibility, attractiveness and traffic safety.

This dissertation adopts a ‘social criticism’ model in order to analyze racism in our contemporary world – particularly the United States. This analysis offers a detailed account of racism as rooted in social structural processes, and prioritizes oppression and domination as the chief wrongs resulting from racism. To do so, said analysis highlights norms, ideals, policies, and actions, that are often assumed to be ‘race neutral’ (e.g., impartiality, merit, ‘natural rights’, and autonomy), and the role they play in the production of racial injustice. More specifically, it exposes how these norms function to undermine human agency by restricting means for self-development and self-determination. As such, the role that inclusive and democratic deliberation can play in combating racial oppression and domination is developed. In light of this analysis, a defense of a ‘concrete morality’ which prioritizes the fight against oppression and domination, is made against an ‘abstract morality’ that adheres to ‘ideally just’ principles regardless of the injustice that results from doing so. Moreover, this project develops a ‘shared responsibility model’ for racial injustice, articulating varying degrees and kinds of responsibility we have for correcting it. It concludes by offering ‘democratic equality of difference’ as a normative ideal for cultivating racial justice. Generally, said ideal aims to: create basic conditions for the self-development and collective self-determination of all; cultivate a universally inclusive and ongoing process of democratic deliberation for solving collective problems; and attend to difference when deliberating about matters of justice. / Philosophy

Educational leadership is challenged with meeting the requirements of No Child Left Behind (NCLB) and the Individuals with Disabilities Education Act (IDEA) legislation which mandates an education for all students. The focus on accessibility and accountability has resulted in more students with disabilities being served in the general education setting. The co-teaching service delivery model is offered in the school environment to provide an education for all students and is intended to include instruction that is specially designed for students with disabilities. Instructional leadership is essential to a successful implementation and maintenance of inclusive practices. This study sought to provide a better understanding of instructional leadership practices of the co-teaching service delivery model. The purpose of the study was to describe and explain how leaders support co-teaching. A distributed perspective based on the combination of activity and distributed cognition theories has been developed to study school leadership. This distributed perspective views leadership practice as an interaction between leaders, followers, and the situation (Spillane, Halverson, and Diamond 2004). This study examined instructional leadership practices of the co-teaching service delivery model at the elementary level. Data were collected through a qualitative design, using interviews, observations, and review of documents. Interviews were conducted with administrators responsible for the direct supervision of the co-teaching model and with co-teachers, both general and special educators. Observations occurred in the school setting and related documents were collected and analyzed. The distributed leadership perspective guided the data collection focusing on leadership tasks and functions, task-enactment, and social and situational distribution of leadership practice. The data revealed leadership tasks that included forming the team, scheduling, assigning instructional roles, allocating resources, and developing the co-teacher relationship. Leadership was shared between the administrators and teachers with both providing leadership. School environment, organizational arrangements with available resources, and participants' profile were identified as factors influencing the leadership practice of co-teaching. It is hoped by understanding the leadership roles and responsibilities of co-teaching, educators may better understand and nurture a co-teaching model that supports students in an inclusive environment. / Ed. D.

The role of teacher leaders in schools is becoming more prevalent as educators examine ways to insure systemic change. It is based on the assumption that education will improve when those closest to the situation are included and encouraged to not only participate in the decision-making process, but also to initiate change. The purpose of this study was to describe the principals' support of teacher leaders in elementary schools in one school system. This study collected data from all public elementary school principals in a large suburban school district in Virginia and from selected elementary level teachers in order to answer the following four research questions: 1. Do elementary principals and/or teachers perceive they support the development of teacher leaders? 2. Do elementary principals and/or teachers perceive teacher leaders serve as a vehicle for shared decision-making? 3. Do elementary principals and/or teachers perceive teacher leaders as instrumental in expanding the focus of shared decision-making to include instructional decisions? 4. Do teachers and/or principals receive preparation at the college/university level to assume teacher leadership positions or as principals to guide teachers to assume leadership positions? The findings of this study indicated that elementary principals and teacher leaders perceive there is support for teacher leaders in their school. There is also agreement that teachers should participate in shared decision-making structures. There is disagreement between the two groups as to the level of participation in such areas as finances, personnel and implementation of new school programs. Finally, the principals do not believe that course work at the university/college level assisted them in promoting and supporting teacher leadership in their school. / Ed. D.

This research investigated the determinants and outcomes of shared mental models of skill use in autonomous work teams. A model of the determinants and outcomes (team task behaviors) of shared mental models of skill use was tested. Three components of shared mental models of skill use were investigated: shared knowledge pertaining to skill use in task performance (i.e., knowledge about the task, equipment, team, and team interaction), shared expectations for skill use in task performance in both routine and non-routine situations, and shared attitudes relevant to skill use in task performance (i.e., collective orientation and collective efficacy). The model included the interdependence, uncertainty, and complexity of the technology; the degree to which the team is cross-trained and its membership stable; and the level of prior experience team members have had with teamwork as the determinants of overlap in a team's mental model of skill use. The beneficial outcomes of a high degree of overlap in the team's mental model of skill use were four team task behaviors: flexibility, quality, verbal communication, and time required in task planning. The flexibility construct was defined as the degree to which a team allocated and used the multiple competencies/skills of each of its members in pursuit of team goals. A model of the development of flexibility was developed as was a theory of the role of shared mental models in flexible skill use. / Ph. D.

This dissertation focuses on the problem space of heterogeneous-ISA multiprocessors – an architectural design point that is being studied by the academic research community and increasingly available in commodity systems. Since such architectures usually lack globally coherent shared memory, software-based distributed shared memory (DSM) is often used to provide the illusion of such a memory. The DSM abstraction typically provides this illusion using a reader-replicate, writer-invalidate memory consistency protocol that operates at the granularity of memory pages and is usually implemented as a first-class operating system abstraction. This enables symmetric multiprocessing (SMP) programming frameworks, augmented with a heterogeneous-ISA compiler, to use CPU cores of different ISAs for parallel computations as if they are of the same ISA, improving programmability, especially for legacy SMP applications which therefore can run unmodified on such hardware. Past DSMs have been plagued by poor performance, in part due to the high latency and low bandwidth of interconnect network infrastructures. The dissertation revisits DSM in light of modern interconnects that reverse this performance trend. The dissertation presents Xfetch, a bulk page prefetching mechanism designed for the DEX DSM system. Xfetch exploits spatial locality, and aggressively and sequentially prefetches pages before potential read faults, improving DSM performance. Our experimental evaluations reveal that Xfetch achieves up to ≈142% speedup over the baseline DEX DSM that does not prefetch page data. SMP programming models often allow primitives that permit weaker memory consistency semantics, where synchronization updates can be delayed, permitting greater parallelism and thereby higher performance. Inspired by such primitives, the dissertation presents a DSM protocol called MWPF that trades-off memory consistency for higher performance in select SMP code regions, targeting heterogeneous-ISA multiprocessor systems. MWPF also overcomes performance bottlenecks of past DSM systems for heterogeneous-ISA multiprocessors such as due to significant number of invalidation messages, false page sharing, large number of read page faults, and large synchronization overheads by using efficient protocol primitives that delay and batch invalidation messages, aggressively prefetch data pages, and perform cross-domain synchronization with low overhead. Our experimental evaluations reveal that MWPF achieves, on average, 11% speedup over the baseline DSM implementation. The dissertation presents PuzzleHype, a distributed hypervisor that enables a single virtual machine (VM) to use fragmented resources in distributed virtualized settings such as CPU cores, memory, and devices of different physical hosts, and thereby decrease resource fragmentation and increase resource utilization. PuzzleHype leverages DSM implemented in host operating systems to present an unified and consistent view of a continuous pseudo-physical address space to guest operating systems. To transparently utilize CPU and I/O resources, PuzzleHype integrates multiple physical CPUs into a single VM by migrating threads, forwarding interrupts, and by delegating I/O. Our experimental evaluations reveal that PuzzleHype yields speedups in the range of 355%–173% over baseline over-provisioning scenarios which are otherwise necessary due to resource fragmentation. To enable a distributed hypervisor to adapt to resource and workload changes, the dissertation proposes the concept of CPU borrowing that allows a VM's virtual CPU (vCPU) to migrate to an available physical CPU (pCPU) and release it when it is no longer necessary, i.e., CPU returning. CPU borrowing can thus be used when a node is over-committed, and CPU returning can be used when the borrowed CPU resource is no longer necessary. To transparently migrate a vCPU at runtime without incurring a significant downtime, the dissertation presents a suite of techniques including leveraging thread migration, loading/restoring vCPU in KVM states, maintaining a global vCPU location table, and creating a DSM kernel thread for handling on-demand paging. Our experimental evaluations reveal that migrating vCPUs to resource-available nodes achieves a speedup of 1.4x over running the vCPUs on distributed nodes. When a VM spans multiple nodes, it is likelihood for failure increases. To mitigate this, the dissertation presents a distributed checkpoint/restart mechanism that allows a distributed VM to tolerate failures. A user interface is introduced for sending/receiving checkpoint/restart commands to a distributed VM. We implement the checkpoint/restart technique in the native KVM tool, and extend it to a distributed mode by converting Inter-Process Communication (IPC) into message passing between nodes, pausing/resuming distributed vCPU executions, and loading/restoring runtime states on the correct set of nodes. Our experimental evaluations indicate that the overhead of checkpointing a distributed VM is ≈10% or less than that of the native KVM tool with our checkpoint support. Restarting a distributed VM is faster than native KVM with our restart support because no additional page faults occur during restarting. The dissertation's final contribution is PopHype, a system software stack that allows simulation of cache-coherent, shared memory heterogeneous-ISA hardware. PopHype includes a Linux operating system that implements DSM as an OS abstraction for processes, i.e., allows multiple processes running on multiple (ISA-different) machines to share memory. With KVM-enabled, this OS becomes a hypervisor that allows multiple, process-based instances of an architecture emulator such as QEMU to execute in a shared address space, allowing multiple QEMU instances to emulate different ISAs in shared memory, i.e., emulate shared memory heterogeneous-ISA hardware. PopHype also includes a modified QEMU to use process-level DSM and an optimized guest OS kernel for improved performance. Our experimental studies confirm PopHype's effectiveness, and reveal that PopHype achieves an average speedup of 7.32x over a baseline that runs multiple QEMU instances in shared memory atop a single host OS. / Doctor of Philosophy / Computing devices are ubiquitous around us. Each of these devices is powered by specialized chips called processors. These processors take in instructions, process them, and produce output. Such processing is what enables us, humans, to send messages to our loved ones, take photographs, as well as carry out various business functions such as using spreadsheet software. The kinds of instructions these processors execute are classified into so-called Instruction Set Architectures or ISAs. Chip designers build processors adopting different ISAs for various applications ranging from computing on mobile phones to cloud computing data centers used by large technology companies. Within a data center, there are typically hundreds of thousands of computing devices that serve an organization's purpose to serve millions or even billions of users. Programming these computers individually to serve a collective goal is an arduous task requiring hundreds of software engineering experts. To simplify programming these computers on a large scale, this thesis envisions an abstraction where tens of devices appear as one computing unit to the programmer, allowing them to program multiple computers as if they are one. This allows for better resource utilization in the sense that the power of multiple computing devices can be pooled together without the need to acquire newer, larger, and more-expensive computers. Furthermore, such pooling allows the software to leverage multiple different ISAs on different computers instead of a single ISA on one computer. This thesis also envisions a way for software to run on multiple computers with potentially different ISAs without exposing the difficulty of managing them to the software engineers.

Within the growing literature on team leadership, there is a lack of understanding which leadership process may be most reflective of intratsk leadership. In study 1, I explored leadership behaviors throughout the operating team's OR tasks and if a shared leadership approach is related to psycho-social attitudes and performance of the team. I also investigate surgical teams' engagement in safety related behaviors and if these are related to the team's workflow disruptions. As an exemplar environment, I chose to observe these dynamics in the operating theater, which is a high-stakes environment that necessitates the team to use both technical and non-technical skills. In study 2, I investigate whether a brief targeted leadership coaching sessions with residents in a simulated environment results in different (increase or decrease) leadership behaviors at an interval of 6 months. Multiple hypothesized models were tested in Study 1. The results of model 1 show that psychological safety and team trust are significantly correlated to each other (r=.704, p= <.001). The results show that psychological safety (β= -.505 p=.049) is related to performance (time of patient on bypass), while team trust (β= .177 p=.303) does not predict performance. The results of model 2 show that more extensive shared leadership behaviors are not significantly correlated with psychological safety (r=.087 p=.250) and performance (r=-.085, p =.295); however, the results show that there is a significant correlation with shared leadership and team trust (r=.260 p =.023), indicating that a more extensive shared leadership approach is related to higher team trust in a surgical team. The results of model 3 show that the length of the time-out (a safety critical behavior) does not mediate the relationship between perceptions of the usefulness of the time-out and frequency with which the circulating nurse leaves the operating room (OR). However, there is a strong relationship between the perceptions of the time-out and the number of times the circulating nurse leaves the OR (β = -.425, p<.001), indicating that for every unit increase in the perceptions of the usefulness of the time-out, the nurse leaves the OR .45 fewer times. In study 2, a paired sample t-test was conducted to understand if leadership behaviors post-coaching session are more frequent than pre-coaching session. The results show that there is no significant difference in the frequency of leadership behaviors at time 1 (M =.113, SD=.040) and the leadership behaviors at time 2 (M= .127, SD= .041); t (6)= -1.216, p = .270. / Doctor of Philosophy / Within the growing literature on team leadership, there is a lack of understanding which leadership process may be most reflective of intratsk leadership. In study 1, I explored leadership behaviors throughout the operating team's OR tasks and if a shared leadership approach is related to psycho-social attitudes and performance of the team. I also investigate surgical teams' engagement in safety related behaviors and if these are related to the team's workflow disruptions. As an exemplar environment, I chose to observe these dynamics in the operating theater, which is a high-stakes environment that necessitates the team to use both technical and non-technical skills. In study 2, I investigate whether a brief targeted leadership coaching sessions with residents in a simulated environment results in different (increase or decrease) leadership behaviors at an interval of 6 months. Multiple hypothesized models were tested in Study 1. The results of model 1 show that psychological safety and team trust are significantly correlated to each other. The results show that psychological safety is related to performance (time of patient on bypass), while team trust does not predict performance. The results of model 2 show that more extensive shared leadership behaviors are not significantly correlated with psychological safety and performance; however, the results show that there is a significant correlation with shared leadership and team trust, indicating that a more extensive shared leadership approach is related to higher team trust in a surgical team. The results of model 3 show that the length of the time-out (a safety critical behavior) does not mediate the relationship between perceptions of the usefulness of the time-out and frequency with which the circulating nurse leaves the operating room (OR). However, there is a strong relationship between the perceptions of the usefulness of the time-out and the number of times the circulating nurse leaves the OR, indicating that for every unit increase in the perceptions of the usefulness of the time-out, the nurse leaves the OR .45 fewer times. In study 2, a paired sample t-test was conducted to understand if leadership behaviors post-coaching session are more frequent than pre-coaching session. The results show that there is no significant difference in the frequency of leadership behaviors at time 1 and the leadership behaviors at time 2.

This dissertation, and its companion dissertation, are the products of a collaborative research project that was conducted by two doctoral students. The process utilized is discussed. The research project focused on site-based management and shared decision-making. Site-based management (SBM) is a strategy that involves the decentralization of authority, and shared decision-making (SOM) among those involved. H is based on the assumption that education will improve when those closest to the situation are included in the decision-making process, and held accountable for their decisions. This study describes the status of SBM/SOM in the public secondary schools of Virginia in regards to teacher and principal participation, size of secondary school, and geographic location. / Ed. D.