TCSC control design for transient stability improvement of a multi-machine power system using trajectory sensitivity

This paper discusses the effects of thyristor controlled series compensator (TCSC), a series FACTS controller, on the transient stability of a power system. Trajectory sensitivity analysis (TSA) has been used to measure the transient stability condition of the system. The TCSC is modeled by a variable capacitor, the value of which changes with the firing angle. It is shown that TSA can be used in the design of the controller. The optimal locations of the TCSC-controller for different fault conditions can also be identified with the help of TSA. The paper depicts the advantage of the use of TCSC with a suitable controller over fixed capacitor operation.

Twelve-month effectiveness of a parent-led, family-focused weight-management program for prepubertal children : a randomized, controlled trial

BACKGROUND Parenting-skills training may be an effective age-appropriate child behavior-modification strategy to assist parents in addressing childhood overweight. OBJECTIVE Our goal was to evaluate the relative effectiveness of parenting-skills training as a key strategy for the treatment of overweight children. DESIGN The design consisted of an assessor-blinded, randomized, controlled trial involving 111 (64% female) overweight, prepubertal children 6 to 9 years of age randomly assigned to parenting-skills training plus intensive lifestyle education, parenting-skills training alone, or a 12-month wait-listed control. Height, BMI, and waist-circumference z score and metabolic profile were assessed at baseline, 6 months, and 12 months (intention to treat). RESULTS After 12 months, the BMI z score was reduced by ∼10% with parenting-skills training plus intensive lifestyle education versus ∼5% with parenting-skills training alone or wait-listing for intervention. Waist-circumference z score fell over 12 months in both intervention groups but not in the control group. There was a significant gender effect, with greater reduction in BMI and waist-circumference z scores in boys compared with girls. CONCLUSION Parenting-skills training combined with promoting a healthy family lifestyle may be an effective approach to weight management in prepubertal children, particularly boys. Future studies should be powered to allow gender subanalysis.

Design of a capacitor supported dynamic voltage restorer (DVR) for unbalanced and distorted loads

The paper discusses the operating principles and control characteristics of a dynamic voltage restorer (DVR) that protects sensitive but unbalanced and/or distorted loads. The main aim of the DVR is to regulate the voltage at the load terminal irrespective of sag/swell, distortion, or unbalance in the supply voltage. In this paper, the DVR is operated in such a fashion that it does not supply or absorb any active power during the steady-state operation. Hence, a DC capacitor rather than a DC source can supply the voltage source inverter realizing the DVR. The proposed DVR operation is verified through extensive digital computer simulation studies.

Design of a static thruster for microair vehicle rotorcraft

This paper presents a case study of a design for a complete microair vehicle thruster. Fixed-pitch small-scale rotors, brushless motors, lithium-polymer cells, and embedded control are combined to produce a mechanically simple, high-performance thruster with potentially high reliability. The custom rotor design requires a balance between manufacturing simplicity and rigidity of a blade versus its aerodynamic performance. An iterative steady-state aeroelastic simulator is used for holistic blade design. The aerodynamic load disturbances of the rotor-motor system in normal conditions are experimentally characterized. The motors require fast dynamic response for authoritative vehicle flight control. We detail a dynamic compensator that achieves satisfactory closed-loop response time. The experimental rotor-motor plant displayed satisfactory thrust performance and dynamic response.

Empirical investigation of interactive highway safety design model accident prediction algorithm : Rural intersections

One major gap in transportation system safety management is the ability to assess the safety ramifications of design changes for both new road projects and modifications to existing roads. To fulfill this need, FHWA and its many partners are developing a safety forecasting tool, the Interactive Highway Safety Design Model (IHSDM). The tool will be used by roadway design engineers, safety analysts, and planners throughout the United States. As such, the statistical models embedded in IHSDM will need to be able to forecast safety impacts under a wide range of roadway configurations and environmental conditions for a wide range of driver populations and will need to be able to capture elements of driving risk across states. One of the IHSDM algorithms developed by FHWA and its contractors is for forecasting accidents on rural road segments and rural intersections. The methodological approach is to use predictive models for specific base conditions, with traffic volume information as the sole explanatory variable for crashes, and then to apply regional or state calibration factors and accident modification factors (AMFs) to estimate the impact on accidents of geometric characteristics that differ from the base model conditions. In the majority of past approaches, AMFs are derived from parameter estimates associated with the explanatory variables. A recent study for FHWA used a multistate database to examine in detail the use of the algorithm with the base model-AMF approach and explored alternative base model forms as well as the use of full models that included nontraffic-related variables and other approaches to estimate AMFs. That research effort is reported. The results support the IHSDM methodology.

Evaluating the effect of a patient education brochure on patients’ expectations and satisfaction with emergency department service

Introduction: The purpose of this study was to assess the capacity of a written intervention, in this case a patient information brochure, to improve patient satisfaction during an Emergency Department (ED) visit. For the purpose of measuring the effect of the intervention the ED journey was conceptualised as a series of distinct areas of service comprising waiting time, service by the triage nurse, care from doctors and nurses and information giving Background of study: Research into patient satisfaction has become a widespread activity endorsed by both governments and hospital administrations. The literature on ED patient satisfaction has consistently indicated three primary areas of patient dissatisfaction: waiting time, nursing care and communication. Recent developments in the literature on patient satisfaction studies however have highlighted the relationship between patients. expectations of a service encounter and their consequent assessment of the experience as dissatisfying or satisfying. Disconfirmation theory posits that the degree to which expectations are confirmed will affect subsequent levels of satisfaction. The conceptual framework utilised in this study is Coye.s (2004) model of disconfirmation. Coye while reiterating satisfaction is a consequence of the degree expectations are either confirmed or disconfirmed also posits that expectations can be modified by interventions. Coye.s work conceptualises these interventions as intra encounter experiences (cues) which function to adjust expectations. Coye suggests some cues are unintended and may have a negative impact which also reinforces the value of planned cues intended to meet or exceed consumer expectations. Consequently the brochure can be characterized as a potentially positive cue, encouraging the patient to understand processes and to orient them in what can be a confronting environment. Only a limited number of studies have examined the effect of written interventions within an ED. No studies could be located which have tested the effect of ED interventions using a conceptual framework which relates the effect of the degree to which expectations are confirmed or disconfirmed in terms of satisfaction with services. Method: Two studies were conducted. Study One used qualitative methods to explore patients. expectations of the ED from the perspective of both patients and health care professionals. Study One was used in part to direct the development of the intervention (brochure) in Study Two. The brochure was an intervention designed to modify patients. expectations thus increasing their satisfaction with the provision of ED service. As there was no existing tools to measure ED patients. expectations and satisfaction a new tool was also developed based on the findings and the literature of Study One. Study Two used a non-randomised, quasi-experimental approach using a non-equivalent post-test only comparison group design used to investigate the effect of the patient education brochure (Stommel and Wills, 2004). The brochure was disseminated to one of two study groups (the intervention group). The effect of the brochure was assessed by comparing the data obtained from both the intervention and control group. These two groups consisted of 150 participants each. It was expected that any differences in the relevant domains selected for examination would indicate the effect of the brochure both on expectation and potentially satisfaction. Results: Study One revealed several areas of common ground between patients and nurses in terms of relevant content for the written intervention, including the need for information on the triage system and waiting times. Areas of difference were also found with patients emphasizing communication issues, whereas focus group members expressed concern that patients were often unable to assimilate verbal information. The findings suggested the potential utility of written material to reinforce verbal communication particularly in terms of the triage process and other ED protocols. This material was synthesized within the final version of the written intervention. Overall the results of Study Two indicated no significant differences between the two groups. The intervention group did indicate a significant number of participants who viewed the brochure of having changed their expectations. The effect of the brochure may have been obscured by a lack of parity between the two groups as the control group presented with statistically significantly higher levels of acuity and experienced significantly shorter waiting times. In terms of disconfirmation theory this would suggest expectations that had been met or exceeded. The results confirmed the correlation of expectations with satisfaction. Several domains also indicated age as a significant predictor with older patients tending to score higher satisfaction results. Other significant predictors of satisfaction established were waiting time and care from nurses, reinforcing the combination of efficient service and positive interpersonal experiences as being valued by patients. Conclusions: Information presented in written form appears to benefit a significant number of ED users in terms of orientation and explaining systems and procedures. The degree to which these effects may interact with other dimensions of satisfaction however is likely to be limited. Waiting time and interpersonal behaviours from staff also provide influential cues in determining satisfaction. Written material is likely to be one element in a series of coordinated strategies to improve patient satisfaction during periods of peak demand.

The effectiveness of a short-term group music therapy intervention for parents who have a child with a disability

The relationship between the quality of parent-child interactions and positive child developmental trajectories is well established (Guralnick, 2006; Shonkoff & Meissels, 2000; Zubrick et al., 2008). However, a range of parental, family, and socio-economic factors can pose risks to parents’ capacity to participate in quality interactions with their children. In particular, families with a child with a disability have been found to have higher levels of parenting stress, and are more likely to experience economic disadvantage, as well as social isolation. The importance of early interventions to promote positive parenting and child development for these families is widely recognised (Shonkoff & Meissels, 2000). However, to date, there is a lack of evidence about the effectiveness of early parenting programs for families who have a young child with a disability. This thesis investigates the impact of a music therapy parenting program, Sing & Grow, on 201 parent-child dyads who attended programs specifically targeted to parents who had a young child with a disability. Sing & Grow is an Australian national early parenting intervention funded by the Australian Government Department of Families, Housing, Community Services and Indigenous Affairs and delivered by Playgroup Queensland. It is designed and delivered by Registered Music Therapists for families with children aged from birth to three years. It aims to improve parenting skills and confidence, improve family functioning (positive parent-child interactions), enhance child development, and provide social networking opportunities to socially isolated families. The intervention targets a range of families in circumstances that have the potential to impact negatively on family functioning. This thesis uses data from the National Evaluation Study of Sing & Grow from programs which were targeted at families who had a young child with a disability. Three studies were conducted to address the objectives of this thesis. Study 1 examines the effects of the Sing & Grow intervention on parent reported pre and post parent mental health, parenting confidence, parenting skills, and child development, and other parent reported outcomes including social support, use of intervention resources, satisfaction with the intervention and perceived benefits of and barriers to participation. Significant improvements from pre to post were found for parent mental health and parent reported child communication and social skills, along with evidence that parents were very satisfied with the program and that it brought social benefits to families. Study 2 explored the pre to post effects of the intervention on children’s developmental skills and parent-child interactions using observational ratings made by clinicians. Significant pre to post improvements were found for parenting sensitivity, parental engagement with child and acceptance of child as well as for child responsiveness to parent, interest, and participation in the intervention, and social skills. Study 3 examined the nature of child and family characteristics that predicted better outcomes for families while taking account of the level of participation in the program. An overall outcome index was calculated and served as the dependent variable in a logistic regression analysis. Families who attended six or more sessions and mothers who had not completed high school were more likely to have higher outcome scores at post intervention than those who attended fewer sessions and those with more educated mothers respectively. The findings of this research indicate that the intervention had a positive impact on participants’ mental health, parenting behaviours and child development and that level of attendance was associated with better outcomes. There was also evidence that the program reached its target of high risk families (i.e., families in which mothers had lower educational levels) and that for these families better outcomes were achieved. There were also indications that the program was accessible and highly regarded by families and that it promoted social connections for participants. A theoretical model of how the intervention is currently working for families is proposed to explain the connections between early parenting, child development and maternal wellbeing. However, more research is required to further elucidate the mechanisms by which the intervention creates change for families. This research presents promising evidence that a short term group music therapy program can elicit important therapeutic benefits for families who have a child with a disability.

Design and analysis of group key exchange protocols

A group key exchange (GKE) protocol allows a set of parties to agree upon a common secret session key over a public network. In this thesis, we focus on designing efficient GKE protocols using public key techniques and appropriately revising security models for GKE protocols. For the purpose of modelling and analysing the security of GKE protocols we apply the widely accepted computational complexity approach. The contributions of the thesis to the area of GKE protocols are manifold. We propose the first GKE protocol that requires only one round of communication and is proven secure in the standard model. Our protocol is generically constructed from a key encapsulation mechanism (KEM). We also suggest an efficient KEM from the literature, which satisfies the underlying security notion, to instantiate the generic protocol. We then concentrate on enhancing the security of one-round GKE protocols. A new model of security for forward secure GKE protocols is introduced and a generic one-round GKE protocol with forward security is then presented. The security of this protocol is also proven in the standard model. We also propose an efficient forward secure encryption scheme that can be used to instantiate the generic GKE protocol. Our next contributions are to the security models of GKE protocols. We observe that the analysis of GKE protocols has not been as extensive as that of two-party key exchange protocols. Particularly, the security attribute of key compromise impersonation (KCI) resilience has so far been ignored for GKE protocols. We model the security of GKE protocols addressing KCI attacks by both outsider and insider adversaries. We then show that a few existing protocols are not secure against KCI attacks. A new proof of security for an existing GKE protocol is given under the revised model assuming random oracles. Subsequently, we treat the security of GKE protocols in the universal composability (UC) framework. We present a new UC ideal functionality for GKE protocols capturing the security attribute of contributiveness. An existing protocol with minor revisions is then shown to realize our functionality in the random oracle model. Finally, we explore the possibility of constructing GKE protocols in the attribute-based setting. We introduce the concept of attribute-based group key exchange (AB-GKE). A security model for AB-GKE and a one-round AB-GKE protocol satisfying our security notion are presented. The protocol is generically constructed from a new cryptographic primitive called encapsulation policy attribute-based KEM (EP-AB-KEM), which we introduce in this thesis. We also present a new EP-AB-KEM with a proof of security assuming generic groups and random oracles. The EP-AB-KEM can be used to instantiate our generic AB-GKE protocol.

Implementing value management as a decision-making tool in the design stages of design and build construction projects : a methodology for improved cost optimization

Value Management (VM) has been proven to provide a structured framework, together with other supporting tools and techniques, that facilitate effective decision-making in many types of projects, thus achieving ‘best value’ for clients. One of the major success factors of VM in achieving better project objectives for clients is through the provision of beneficial input by multi-disciplinary team members being involved in critical decision-making discussions during the early stage of construction projects. This paper describes a doctoral research proposal based on the application of VM in design and build construction projects, especially focusing on the design stage. The research aims to study the effects of implementing VM in design and build construction projects, in particular how well the methodology addresses issues related to cost overruns resulting from poor coordination and overlooking of critical constructability issues amongst team members in construction projects in Malaysia. It is proposed that through contractors’ early involvement during the design stage, combined with the use of the VM methodology, particularly as a decision-making tool, better optimization of construction cost can be achieved, thus promoting more efficient and effective constructability. The main methods used in this research involve a thorough literature study, semi-structured interviews, and a survey of major stakeholders, a detailed case study and a VM workshop and focus group discussions involving construction professionals in order to explore and possibly develop a framework and a specific methodology for the facilitating successful application of VM within design and build construction projects.

Controller structure and design of firing angle controllers for (unit connected) HVDC systems

This paper investigates the control of a HVDC link, fed from an AC source through a controlled rectifier and feeding an AC line through a controlled inverter. The overall objective is to maintain maximum possible link voltage at the inverter while regulating the link current. In this paper the practical feedback design issues are investigated with a view of obtaining simple, robust designs that are easy to evaluate for safety and operability. The investigations are applicable to back-to-back links used for frequency decoupling and to long DC lines. The design issues discussed include: (i) a review of overall system dynamics to establish the time scale of different feedback loops and to highlight feedback design issues; (ii) the concept of using the inverter firing angle control to regulate link current when the rectifier firing angle controller saturates; and (iii) the design issues for the individual controllers including robust design for varying line conditions and the trade-off between controller complexity and the reduction of nonlinearity and disturbance effects

Implications for the design of a digital stethoscope for anaesthetic preadmission consultations

Background This research addresses the development of a digital stethoscope for use with a telehealth communications network to allow doctors to examine patients remotely (a digital telehealth stethoscope). A telehealth stethoscope would allow remote auscultation of patients who do not live near a major hospital. Travelling from remote areas to major hospitals is expensive for patients and a telehealth stethoscope could result in significant cost savings. Using a stethoscope requires great skill. To design a telehealth stethoscope that meets doctors’ expectations, the use of existing stethoscopes in clinical contexts must be examined. Method Observations were conducted of 30 anaesthetic preadmission consultations. The observations were video- taped. Interaction between doctor, patient and non-human elements in the consultation were “coded” to transform the video into data. The data were analysed to reveal essential aspects of the interactions. Results The analysis has shown that the doctor controls the interaction during auscultation. The conduct of auscultation draws heavily on the doctor’s tacit knowledge, allowing the doctor to treat the acoustic stethoscope as infrastructure – that is, the stethoscope sinks into the background and becomes completely transparent in use. Conclusion Two important, and related, implications for the design of a telehealth stethoscope have arisen from this research. First, as a telehealth stethoscope will be a shared device, doctors will not be able to make use of their existing expertise in using their own stethoscopes. Very simply, a telehealth stethoscope will sound different to a doctor’s own stethoscope. Second, the collaborative interaction required to use a telehealth stethoscope will have to be invented and refined. A telehealth stethoscope will need to be carefully designed to address these issues and result in successful use. This research challenges the concept of a telehealth stethoscope by raising questions about the ease and confidence with which doctors could use such a device.

Aggression in Sexually Abused Trafficked Girls and Efficacy of Intervention

The broad objective of this study was to understand the incidence and severity of aggression among sexually abused girls who were trafficked and who were then further used for commercial sexual exploitation (referred to subsequently as sexually abused trafficked girls). In addition, the impact of counseling for minimizing aggression in these girls was investigated. A group of 120 sexually abused trafficked Indian girls and a group of 120 nonsexually abused Indian girls, aged 13 to 18, participated in the study. The sexually abused trafficked girls were purposively selected from four shelters located in and around Kolkata, India. The nonsexually abused girls were selected randomly from four schools situated near the shelters, and these girls were matched by age with the sexually abused trafficked girls. Data were collected using a Background Information Schedule and a standardized psychological test, that is, The Aggression Scale. Results revealed that 16.7% of the girls were first sexually abused between 6 and 9 years of age, 37.5% between 10 and 13 years of age, and 45.8% between 14 and 17 years of age. Findings further revealed that 4.2% of the sexually abused trafficked girls demonstrated saturated aggression, and 26.7% were highly aggressive, that is, extremely frustrated and rebellious. Across age groups, the sexually abused trafficked girls suffered from more aggression (p < .05), compared with the nonvictimized girls. Psychological interventions, such as individual and group counseling, were found to have a positive impact on the sexually abused trafficked girls. These findings should motivate counselors to deal with sexually abused children. It is also hoped that authorities in welfare homes will understand the importance of counseling for sexually abused trafficked children, and will appoint more counselors for this purpose.

Equity and research design

This chapter recognizes that research is a cultural invention and explains why. It discusses what equity, research and research design mean, and suggests that the concept of equity is enriched considerably when ideas from Indigenous, critical and politically committed research traditions are involved in research design. When research design and the processes of research are guided by principles of equity, several issues warrant investigation. These include power relations, deficit models of research, homogeneity and reflexivity. Research design that is informed by principles of equity is explicit in its political purpose of seeking socially just outcomes for the short and long term.