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This qualitative study sought to gain deeper insights into how English Language Heads of Department (H.O.D.) perceive their roles in teacher development and efficacy, what leadership style inform their role enactment and the different skill sets and beliefs they take to their H.O.D. roles. The population was limited to selected schools in central Jamaica with a sample size of eight Heads of Departments in upgraded and traditional high schools. The motivation to conduct this research arose out of the concerns about Jamaica’s poor ratings in CXC English Language passes and my perception that insights into how H.O.D.s perceived their roles could possibly generate a solution to enable them to facilitate teaching learning experiences that could redound to improved CXC English Language results. Extensive case-based interviews, ranking activity and stimulated recall of artefacts were my primary sources of data, and I used open coding axial coding systems to analyze my data. Presently H.O.D.s engage in more traditional roles align them to a transactional approach as their leadership style. However, the changing roles of the H.O.D.s demand a more transformational leadership style. The findings suggest that some H.O.D.s’ approach is transformational, some transactional, while others display no distinct leadership style. Some play an excellent role in teacher development and efficacy, others play very little or no role. H.O.D.s perception of their role conflict with how they enact these roles and what they believe about them. The conclusion is that i H.O.D.s need a comprehensive system of training in their H.O.D.s specific roles and to help them develop and utilize more transformational leadership skills for use with their departments. Keywords: transformational and transactional leadership, heads of department/department chairs, Jamaican education / Teaching & Learning

Under hela skolgången och i alla skolans ämnen stöter elever på texter. Utifrån det syftar denna studie till att undersöka hur lärare arbetar med textläsning för att eleverna ska förstå textens innehåll. Inriktningen har varit på läsförståelsearbete i andra ämnen än svenska. Våra teoretiska utgångspunkter har varit modellerna Reciprocal teaching och Transaction instruction strategies, varav båda tar upp flertalet strategier vad gäller läsförståelse.  Som metod har observationer använts, där två lärare i årskurs 4 respektive 5 observerats under totalt sex olika lektioner i ämnena matematik, biologi, geografi och historia. Efter observationerna visar resultatet att lärarna till stor del använder sig av de olika lässtrategierna som våra teorier tar upp, som till exempel textsammanfattning och att koppla texten till tidigare erfarenheter och kunskaper. I matematikundervisning är dock användningen av lässtrategier inte lika vanligt förekommande, åtminstone inte på de två matematiklektioner som har observerats. Därför har också längden på studien problematiserats utifrån att alla lektioner inte innehåller arbete med läsning. Utifrån det föreslås bland annat studier under längre tidsperioder med användning av Reciprocal teaching och Transactional instruction strategies, där man också kan ta del av elevers resultat och utveckling.

In this dissertation, we consider the problem of scheduling and synchronization of distributable real-time threads --- Real-Time CORBA's first-class abstraction for programming real-time, multi-node sequential behaviors. Distributable real-time threads can be scheduled, broadly, using two paradigms: node independent scheduling, in which nodes independently construct thread schedules, based on node-level decomposition of distributable thread (or DT) scheduling parameters, and collaborative scheduling, in which nodes collaborate to construct system-wide thread schedules, which may or may not involve scheduling parameter decomposition. While significant literature exists on node independent scheduling, little is known about collaborative scheduling and its concomitant tradeoffs. We design three collaborative scheduling algorithms, called ACUA, QBUA, and DQBUA. ACUA uses theory of consensus and QBUA uses theory of quorums for distributable thread schedule construction. DQBUA extends QBUA with lock-based, local and distributed concurrency control. The algorithms consider a model where distributable threads arrive arbitrarily, have time/utility function time constraints, access resources in an arbitrary way (e.g., arbitrary lock acquire/release order, arbitrary nestings), and are subject to arbitrary node crash failures and message losses. We analytically establish several properties of the algorithms including probabilistic end-to-end termination time satisfactions, timeliness optimality during underloads, bounded exception handling time, and correctness of the algorithms in partially synchronous systems. We implement distributable real-time threads in the Linux kernel as a first-class programming and scheduling abstraction. The resulting kernel, called ChronOS, provides application interfaces for creating and manipulating distributable threads, as well as kernel interfaces and mechanisms for scheduling them (using both independent and collaborative approaches). ChronOS also has failure detector mechanisms for detecting and recovering from distributable thread failures. We implement the proposed scheduling algorithms and their competitors in ChronOS and compare their behavior. Our studies reveal that the collaborative scheduling algorithms are superior to independent scheduling algorithms for certain thread sets, in particular, when thread sections have significantly varying execution time. This variability, especially if the variability is not consistent among the threads, may cause each node to make conflicting decisions in the absence of global information. We observe that collaborative schedulers outperform independent schedulers (e.g., EDF augmented with PIP) in terms of accrued utility by as much as 75%. We identify distributed dependencies as one of the major sources of overhead in collaborative scheduling. In particular, the cost of distributed lock-based concurrency control (e.g., lock management, distributed deadlock detection/resolution) can significantly reduce the problem space for which collaborative scheduling is beneficial. To mitigate this, we consider the use of software transactional memory (or STM), an optimistic, non-blocking synchronization alternative to lock-based concurrency control which has been extensively studied in non real-time contexts. We consider distributable real-time threads with STM concurrency control, and develop techniques for analyzing and bounding their end-to-end response times on distributed single-processor and distributed multiprocessor systems. We also develop contention management techniques, a key component of STM, which are driven by threads' real-time scheduling parameters, and establish their tradeoffs against non-real-time contention managers. / Ph. D.

The study addressed the problem that, although researchers have clearly identified areas of stress for clergy wives and suggested the use of counseling services, they have not identified effective counseling interventions. Clergy wives referred to non-clergy women married to Protestant clergymen. The study included (a) the development of Clergy Wife Wings (CWW), a 5-session psychoeducational group plan for 6 to 10 clergy wives, to alleviate ministry-related stress and (b) the formative evaluation of the plan in its first implementation. Conclusions drawn suggested that CWW showed good potential as an intervention in helping clergy wives to move towards alleviation of stress but needed revisions and additional implementation and evaluation. Recommendations provided a detailed list of specific revisions. CWW had an outcome goal for participants of decreasing ministry-related stress, particularly in three targeted stress domains: role expectations and time demands, clergy family boundary intrusiveness, and lack of social support. As presented in the literature review, the theoretical foundations in stress came from the multimodal-transactional model of stress and its treatment (Palmer, S. & Dryden, W., 1995) and from REBT. The literature review also contained, after a summary of the history of clergy wives, an overview of the plan, with references supporting the components. The plan included pre and post-group testing with two clergy-wife stress assessment instruments -- adaptations of the Clergy Family Life Inventory (Blanton, P., Morris, L, & Anderson, D., 1990) and of the Normative Stress Scale for Clergy Wives (Huebner, 1998). The formative evaluation of the group plan, in its first implementation, identified themes concerning effectiveness, strengths, weaknesses, and suggestions for improvement. These themes emerged from the qualitative analysis of various documents completed by the 9 participants, the group facilitator, and a group observer. Qualitative findings suggested effectiveness of Clergy Wife Wings through themes of participant perceptions and of reported changes in their thinking and behavior related to stress. Quantitative findings, however, from the pre and post-group measures on the clergy-wife stress instruments did not suggest effectiveness, except for a significant decrease in stress related to two of 35 stressor statements. Discussion included possible reasons for the disparity between findings. / Ph. D.

Lock-based synchronization on multiprocessors is inherently non-scalable, non-composable, and error-prone. These problems are exacerbated in distributed systems due to an additional layer of complexity: multinode concurrency. Transactional memory (TM) is an emerging, alternative synchronization abstraction that promises to alleviate these difficulties. With the TM model, code that accesses shared memory objects are organized as transactions, which speculatively execute, while logging changes. If transactional conflicts are detected, one of the conflicting transaction is aborted and re-executed, while the other is allowed to commit, yielding the illusion of atomicity. TM for multiprocessors has been proposed in software (STM), in hardware (HTM), and in a combination (HyTM). This dissertation focuses on supporting the TM abstraction in distributed systems, i.e., distributed STM (or D-STM). We focus on three problem spaces: cache-coherence (CC), conflict resolution, and replication. We evaluate the performance of D-STM by measuring the competitive ratio of its makespan --- i.e., the ratio of its makespan (the last completion time for a given set of transactions) to the makespan of an optimal off-line clairvoyant scheduler. We show that the performance of D-STM for metric-space networks is O(N^2) for N transactions requesting an object under the Greedy contention manager and an arbitrary CC protocol. To improve the performance, we propose a class of location-aware CC protocols, called LAC protocols. We show that the combination of the Greedy manager and a LAC protocol yields an O(NlogN s) competitive ratio for s shared objects. We then formalize two classes of CC protocols: distributed queuing cache-coherence (DQCC) protocols and distributed priority queuing cache-coherence (DPQCC) protocols, both of which can be implemented using distributed queuing protocols. We show that a DQCC protocol is O(NlogD)-competitive and a DPQCC protocol is O(log D_delta)-competitive for N dynamically generated transactions requesting an object, where D_delta is the normalized diameter of the underlying distributed queuing protocol. Additionally, we propose a novel CC protocol, called Relay, which reduces the total number of aborts to O(N) for N conflicting transactions requesting an object, yielding a significantly improvement over past CC protocols which has O(N^2) total number of aborts. We also analyze Relay's dynamic competitive ratio in terms of the communication cost (for dynamically generated transactions), and show that Relay's dynamic competitive ratio is O(log D_0), where D_0 is the normalized diameter of the underlying network spanning tree. To reduce unnecessary aborts and increase concurrency for D-STM based on globally-consistent contention management policies, we propose the distributed dependency-aware (DDA) conflict resolution model, which adopts different conflict resolution strategies based on transaction types. In the DDA model, read-only transactions never abort by keeping a set of versions for each object. Each transaction only keeps precedence relations based on its local knowledge of precedence relations. We show that the DDA model ensures that 1) read-only transactions never abort, 2) every transaction eventually commits, 3) supports invisible reads, and 4) efficiently garbage collects useless object versions. To establish competitive ratio bounds for contention managers in D-STM, we model the distributed transactional contention management problem as the traveling salesman problem (TSP). We prove that for D-STM, any online, work conserving, deterministic contention manager provides an Omega(max[s,s^2/D]) competitive ratio in a network with normalized diameter D and s shared objects. Compared with the Omega(s) competitive ratio for multiprocessor STM, the performance guarantee for D-STM degrades by a factor proportional to s/D. We present a randomized algorithm, called Randomized, with a competitive ratio O(sClog n log ^{2} n) for s objects shared by n transactions, with a maximum conflicting degree C. To break this lower bound, we present a randomized algorithm Cutting, which needs partial information of transactions and an approximate TSP algorithm A with approximation ratio phi_A. We show that the average case competitive ratio of Cutting is O(s phi_A log^{2}m log^{2}n), which is close to O(s). Single copy (SC) D-STM keeps only one writable copy of each object, and thus cannot tolerate node failures. We propose a quorum-based replication (QR) D-STM model, which provides provable fault-tolerance without incurring high communication overhead, when compared with the SC model. The QR model stores object replicas in a tree quorum system, where two quorums intersect if one of them is a write quorum, and ensures the consistency among replicas at commit-time. The communication cost of an operation in the QR model is proportional to the communication cost from the requesting node to its closest read or write quorum. In the presence of node failures, the QR model exhibits high availability and degrades gracefully when the number of failed nodes increases, with reasonable higher communication cost. We develop a protoytpe implementation of the dissertation's proposed solutions, including DQCC and DPQCC protocols, Relay protocol, and the DDA model, in the HyFlow Java D-STM framework. We experimentally evaluated these solutions with respective competitor solutions on a set of microbenchmarks (e.g., data structures including distributed linked list, binary search tree and red-black tree) and macrobenchmarks (e.g., distributed versions of the applications in the STAMP STM benchmark suite for multiprocessors). Our experimental studies revealed that: 1) based on the same distributed queuing protocol (i.e., Ballistic CC protocol), DPQCC yields better transactional throughput than DQCC, by a factor of 50% - 100%, on a range of transactional workloads; 2) Relay outperforms competitor protocols (including Arrow, Ballistic and Home) by more than 200% when the network size and contention increase, as it efficiently reduces the average aborts per transaction (less than 0.5); 3) the DDA model outperforms existing contention management policies (including Greedy, Karma and Kindergarten managers) by upto 30%-40% in high contention environments; For read/write-balanced workloads, the DDA model outperforms these contention management policies by 30%-60% on average; for read-dominated workloads, the model outperforms by over 200%. / Ph. D.

While innovation has been a critical tool for the success of hospitality businesses, there has been little research concerning how hospitality service innovation is created. Focusing on knowledge development for service innovation, this dissertation examines hospitality open innovation processes by highlighting the critical role of customers as important external stakeholders for knowledge creation. More specifically, this research examines how hospitality brand community members engage in brand activities that co-create non-transactional knowledge value for open innovation. To achieve the research purpose, the dissertation consists of four independent studies. The design of the four studies followed a theory development process focusing on bibliometric analysis (Study 1), exploratory analysis (Study 2), empirical analysis (Study 3), and experimental analysis (Study 4). Study 1 conducted bibliometric co-citation analysis to examine the foundation and evolution of the service innovation research in both hospitality and tourism and service management literature. Study 2 examined how hospitality (hotel) customers engage in an online brand community and what types of value are co-created from their engagement behaviors. Study 3 empirically developed a multi-dimensional measure of customer engagement behaviors for co-creating non-transactional value. Lastly, Study 4 examined how hospitality online brand community members participate in open innovation behaviors as a result of customer empowerment and social recognition. Study 1 identified critical research opportunities for future hospitality and tourism research in terms of innovation creation, diffusion, and evaluation. Most importantly, open innovation via customer engagement was identified as a critical topic to understand hospitality innovation creation. In Study 2, customer engagement behaviors, motivations, and value co-creation were qualitatively analyzed in the context of an online hotel brand community. Using mixed-methods, including netnography analysis and qualitative written interviews, a conceptual framework of value co-creation via customer engagement was developed. Based on this framework, Study 3 developed a scale consisting of 15 items measuring customer engagement behaviors in terms of influential-experience value, C-to-B innovation value, relational value, and citizenship value. Lastly, Study 4 found a causal process that customer empowerment makes a positive impact on the intention of open innovation engagement and the creativity of ideas by mediating intrinsic motivation. / Doctor of Philosophy / While innovation has been a critical tool for the success of hospitality businesses, there has been little research concerning how hospitality service innovation is created. Focusing on knowledge development for service innovation, this dissertation examines hospitality open innovation processes by highlighting the critical role of customers as important external stakeholders for knowledge creation. More specifically, this research examines how hospitality brand community members engage in brand activities that co-create non-transactional knowledge value for open innovation. To achieve the research purpose, the dissertation consists of four independent studies. The design of the four studies followed a theory development process focusing on bibliometric critical literature review analysis (Study 1), exploratory analysis (Study 2), empirical analysis (Study 3), and experimental analysis (Study 4). Specifically, Study 1 critically analyzed service innovation academic studies published in the last decade in both hospitality and tourism and service management journals to get insights into future research directions. Study 2 analyzed how hospitality (hotel) customers engage in online brand community activities in terms of the benefits of the behaviors and the motivations for the engagement behaviors. Study 3 developed a practical tool to measure customer engagement behaviors. Lastly, Study 4 investigated how hospitality online brand community members participate in idea sharing behaviors in terms of customer empowerment and social recognition. Study 1 identified critical research opportunities for future hospitality and tourism research in terms of innovation creation, diffusion, and evaluation. Most importantly, open innovation via customer engagement was identified as a critical topic to understand hospitality innovation creation. Focusing on the open innovation, Study 2 analyzed hospitality customers' various engagement activities and contents created from the activities in an online hotel brand community. A conceptual framework of value co-creation via customer engagement behaviors was developed. Based on this framework, Study 3 developed a scale consisting of 15 items measuring customer engagement behaviors in terms of influential-experience value, C-to-B innovation value, relational value, and citizenship value. Lastly, Study 4 found that customers are likely to share their service ideas with hospitality practitioners when they enjoy doing so with the belief that their ideas can affect brand management decisions.