JTP: An Energy-conscious Transport Protocol for Wireless Ad Hoc Networks

Within a recently developed low-power ad hoc network system, we present a transport protocol (JTP) whose goal is to reduce power consumption without trading off delivery requirements of applications. JTP has the following features: it is lightweight whereby end-nodes control in-network actions by encoding delivery requirements in packet headers; JTP enables applications to specify a range of reliability requirements, thus allocating the right energy budget to packets; JTP minimizes feedback control traffic from the destination by varying its frequency based on delivery requirements and stability of the network; JTP minimizes energy consumption by implementing in-network caching and increasing the chances that data retransmission requests from destinations "hit" these caches, thus avoiding costly source retransmissions; and JTP fairly allocates bandwidth among flows by backing off the sending rate of a source to account for in-network retransmissions on its behalf. Analysis and extensive simulations demonstrate the energy gains of JTP over one-size-fits-all transport protocols.Defense Advanced Research Projects Agency (AFRL FA8750-06-C-0199

Faculty Recital: Leah Partridge, soprano, The Many Phases of Love

Kennesaw State University School of Music presents The Many Phases of Love, a concert of arias, songs and piano pieces featuring Leah Partridge, soprano with Craig Ketter, piano.https://digitalcommons.kennesaw.edu/musicprograms/1372/thumbnail.jp

Study and Simulation of Enhancements for TCP (Transmission Control Protocol) Performance Over Noisy, High-Latency Links

The designers of the TCP/IP protocol suite explicitly included support of satellites in their design goals. The goal of the Internet Project was to design a protocol which could be layered over different networking technologies to allow them to be concatenated into an internet. The results of this project included two protocols, IP and TCP. IP is the protocol used by all elements in the network and it defines the standard packet format for IP datagrams. TCP is the end-to-end transport protocol commonly used between end systems on the Internet to derive a reliable bi-directional byte-pipe service from the underlying unreliable IP datagram service. Satellite links are explicitly mentioned in Vint Cerf's 2-page article which appeared in 1980 in CCR [2] to introduce the specifications for IP and TCP. In the past fifteen years, TCP has been demonstrated to work over many differing networking technologies, including over paths including satellites links. So if satellite links were in the minds of the designers from the beginning, what is the problem? The problem is that the performance of TCP has in some cases been disappointing. A goal of the authors of the original specification of TCP was to specify only enough behavior to ensure interoperability. The specification left a number of important decisions, in particular how much data is to be sent when, to the implementor. This was deliberately' done. By leaving performance-related decisions to the implementor, this would allow the protocol TCP to be tuned and adapted to different networks and situations in the future without the need to revise the specification of the protocol, or break interoperability. Interoperability would continue while future implementations would be allowed flexibility to adapt to needs which could not be anticipated at the time of the original protocol design

Transitions at the end of life for older adults - patient, carer and professional perspectives

BackgroundThe end of life may be a time of high service utilisation for older adults. Transitions between care settings occur frequently, but may produce little improvement in symptom control or quality of life for patients. Ensuring that patients experience co-ordinated care, and moves occur because of individual needs rather than system imperatives, is crucial to patients’ well-being and to containing health-care costs.ObjectiveThe aim of this study was to understand the experiences, influences and consequences of transitions between settings for older adults at the end of life. Three conditions were the focus of study, chosen to represent differing disease trajectories.SettingEngland.ParticipantsThirty patients aged over 75 years, in their last year of life, diagnosed with heart failure, lung cancer and stroke; 118 caregivers of decedents aged 66–98 years, who had died with heart failure, lung cancer, stroke, chronic obstructive pulmonary disease or selected other cancers; and 43 providers and commissioners of services in primary care, hospital, hospice, social care and ambulance services.Design and methodsThis was a mixed-methods study, composed of four parts: (1) in-depth interviews with older adults; (2) qualitative interviews and structured questionnaire with bereaved carers of older adult decedents; (3) telephone interviews with care commissioners and providers using case scenarios derived from the interviews with carers; and (4) analysis of linked Hospital Episode Statistics (HES) and mortality data relating to hospital admissions for heart failure and lung cancer in England 2001–10.ResultsTransitions between care settings in the last year of life were a common component of end-of-life care across all the data sets that made up this study, and many moves were made shortly before death. Patients’ and carers’ experiences of transitions were of a disjointed system in which organisational processes were prioritised over individual needs. In many cases, the family carer was the co-ordinator and provider of care at home, excluded from participation in institutional care but lacking the information and support to extend their role with confidence. The general practitioner (GP) was a valued, central figure in end-of-life care across settings, though other disciplines were critical of GPs’ expertise and adherence to guidelines. Out-of-hours services and care homes were identified by many as contributors to unnecessary transitions. Good relationships and communication between professionals in different settings and sectors was recognised by families as one of the most important influences on transitions but this was rarely acknowledged by staff.ConclusionsDevelopment of a shared understanding of professional and carer roles in end-of-life transitions may be one of the most effective ways of improving patients’ experiences. Patients and carers manage many aspects of end-of-life care for themselves. Identifying ways to extend their skills and strengthen their voices, particularly in hospital settings, would be welcomed and may reduce unnecessary end-of-life transitions. Why the experiences of carers appear to have changed little, despite the implementation of a range of relevant policies, is an important question that has not been answered. Recommendations for future research include the relationship between policy interventions and the experiences of end-of-life carers; identification of ways to harmonise understanding of the carers’ role and strengthen their voice, particularly in hospital settings; identification of ways to reduce the influence of interprofessional tensions in end-of-life care; and development of interventions to enhance patients’ experiences across transitions.FundingThe National Institute for Health Research Health Services and Delivery Research programme

2010 Forest Carbon Workgroup: Final Report

This document provides a detailed report and recommendations of the 2010 Forest Carbon Work group to the Director of the Department of Ecology and the Commissioner of Public Lands. The recommendations relate to the critical role Washington’s forest lands will play in addressing the challenge of climate change; appropriate responses to pressure for conversion of working forest lands to non-forest uses; and the role of ecosystem service markets, including carbon offset markets, and other incentive systems in bringing about desired results. The 2010 Work group included some members of a similar 2008 Work group and built on the results of that 2008 effort. The report appendix contains purpose statements by each participating interest, explaining its rationale for participation. In light of the 2010 Work group emphasis, this document focused on three topics: Forest carbon considerations in avoiding forest land use conversion; incentives to reward forest landowners for providing ecosystem services, including carbon storage and improvement of forest health; and features of forest carbon offset protocols and registries that are appropriate for use by forest offset project developers in Washington State