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Service Area (service + area)
Selected AbstractsRadio resource management across multiple protocol layers in satellite networks: a tutorial overviewINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2005Paolo Barsocchi Abstract Satellite transmissions have an important role in telephone communications, television broadcasting, computer communications, maritime navigation, and military command and control. Moreover, in many situations they may be the only possible communication set-up. Trends in telecommunications indicate that four major growth market/service areas are messaging and navigation services (wireless and satellite), mobility services (wireless and satellite), video delivery services (cable and satellite), and interactive multimedia services (fibre/cable, satellite). When using geostationary satellites (GEO), the long propagation delay may have great impact, given the end-to-end delay user's requirements of relevant applications; moreover, atmospheric conditions may seriously affect data transmission. Since satellite bandwidth is a relatively scarce resource compared to the terrestrial one (e.g. in optical transport networks), and the environment is harsher, resource management of the radio segment plays an important role in the system's efficiency and economy. The radio resource management (RMM) entity is responsible for the utilization of the air interface resources, and covers power control, handover, admission control, congestion control, bandwidth allocation, and packet scheduling. RRM functions are crucial for the best possible utilization of the capacity. RRM functions can be implemented in different ways, thus having an impact on the overall system efficiency. This tutorial aims to provide an overview of satellite transmission aspects at various OSI layers, with emphasis on the MAC layer; some cross-layer solutions for bandwidth allocation are also indicated. Far from being an exhaustive survey (mainly due to the extensive nature of the subject), it offers the readers an extensive bibliography, which could be used for further research on specific aspects. Copyright © 2005 John Wiley & Sons, Ltd. [source] Substance use disorders in an Australian community surveyDRUG AND ALCOHOL REVIEW, Issue 3 2002MAREE TEESSON Abstract A community survey of the common mental disorders in a geographically defined treatment service area was used to explore the socio-demographic correlates and service utilization of people with alcohol and drug use disorders living in the area. These data represent the most comprehensive data on substance use disorders in a defined geographic region in Australia. Alcohol and drug use disorders were most likely to be found in the young, with those aged 18,34 uyears being three times more likely to have an alcohol use disorder than those aged 55 years and over. A third (33%) of those people with an alcohol use disorder and 42% of those with a drug use disorder had consulted a health professional in the past 12 months for their substance use disorder. [source] Incidence of Status Epilepticus in Adults in Germany: A Prospective, Population-Based StudyEPILEPSIA, Issue 6 2001Susanne Knake Summary: ,Purpose: To determine the incidence and case-fatality rate of status epilepticus (SE) in adults in Hessen, Germany, we performed a prospective, population-based study from July 1997 through June 1999. Methods: All adult patients residing within the zip-code area 35 (area-35) with SE were included. Area-35 had 743.285 adult inhabitants, including 123.353 adult inhabitants of the primary service area of the University Hospital Marburg (PS-area). Patients were reported by 16 hospitals in the area and were prospectively identified and carefully reviewed within 5 days by one of the authors. Based on the crude annual incidence of SE and a rate of underascertainment of 10% determined for the PS-area, the corrected, age-adjusted incidence of SE in area 35, more representative of the population of Germany, was calculated. Results: The crude annual incidence in the PS-area was 15.8/100,000 [95% confidence interval (CI), 11.2,21.6]. The calculated, corrected, age-adjusted incidence of SE in area 35 was 17.1/100,000. It was higher for men compared with women (26.1 vs. 13.7) and for those aged 60 years and older (54.5 vs. 4.2/100,000, p < 0.0001). The etiology was mainly remote symptomatic due to cerebrovascular disease. Epilepsy was previously diagnosed in only 50% of the patients. The case-fatality rate was 9.3%. Conclusions: Based on our data, at least 14,000 patients would be affected by SE in Germany, associated with ,1,300 deaths annually. The incidence of SE in Germany is similar to that found in the white United States population. Furthermore, this study confirms the higher incidence of SE in male patients and in the elderly population. This may be due to a higher incidence of cerebrovascular disease in these subpopulations. [source] Optimal feeder bus routes on irregular street networksJOURNAL OF ADVANCED TRANSPORTATION, Issue 2 2000Steven Chien The methodology presented here seeks to optimize bus routes feeding a major intermodal transit transfer station while considering intersection delays and realistic street networks. A model is developed for finding the optimal bus route location and its operating headway in a heterogeneous service area. The criterion for optimality is the minimum total cost, including supplier and user costs. Irregular and discrete demand distributions, which realistically represent geographic variations in demand, are considered in the proposed model. The optimal headway is derived analytically for an irregularly shaped service area without demand elasticity, with non-uniformly distributed demand density, and with a many-to-one travel pattern. Computer programs are designed to analyze numerical examples, which show that the combinatory type routing problem can be globally optimized. The improved computational efficiency of the near-optimal algorithm is demonstrated through numerical comparisons to an optimal solution obtained by the exhaustive search (ES) algorithm. The CPU time spent by each algorithm is also compared to demonstrate that the near-optimal algorithm converges to an acceptable solution significantly faster than the ES algorithm. [source] Evaluating home visitation: A case study of evaluation at the David and Lucile Packard FoundationNEW DIRECTIONS FOR EVALUATION, Issue 105 2005Kay E. Sherwood The David and Lucile Packard Foundation employed an evaluation-focused grant-making strategy over more than a decade in a particular child development service area, the home visitation approach, that illustrates, among other lessons, the management of disappointing evaluation results. [source] AHEC in West Virginia: A Case StudyTHE JOURNAL OF RURAL HEALTH, Issue 1 2003Lamont D. Nottingham MPH The outcome is an evolving universitycommunity partnership designed to meet changing workforce and community health needs in the heart of rural Appalachia. West Virginia University's (WVU's) application of the original Carnegie Commission AHEC recommendations (1970) resulted in the Charleston AHEC, now part of the Robert C. Byrd Health Sciences Center of WVU. AHEC today trains more than 135 residents and interns, and one-third of the third-year and fourth-year WVU medical students. Charleston offers clinical and continuing education for nurses, dentists, pharmacists, and allied health professionals. A health sciences library, distance learning, and a neiwork of primary care clinics help define Charleston's unique AHEC role. This AHEC hub continues to meet the classic Carnegie goals of recruiting and retaining health professionals, and providing access to care in the original service area and statewide. Based on the Charleston experience, four new federally funded AHECs are being developed to link rural primary care residencies with the state-funded West Virginia rural health education partnerships. These rural consortia AHECs are applying the concept of community competency, a performance-based methodology, to integrate learning while achieving the goals of Healthy People 2010. [source] Geographic Variation in End-Stage Renal Disease Incidence and Access to Deceased Donor Kidney TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2010A. K. Mathur The effect of demand for kidney transplantation, measured by end-stage renal disease (ESRD) incidence, on access to transplantation is unknown. Using data from the U.S. Census Bureau, Centers for Medicare & Medicaid Services (CMS) and the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients (OPTN/SRTR) from 2000 to 2008, we performed donation service area (DSA) and patient-level regression analyses to assess the effect of ESRD incidence on access to the kidney waiting list and deceased donor kidney transplantation. In DSAs, ESRD incidence increased with greater density of high ESRD incidence racial groups (African Americans and Native Americans). Wait-list and transplant rates were relatively lower in high ESRD incidence DSAs, but wait-list rates were not drastically affected by ESRD incidence at the patient level. Compared to low ESRD areas, high ESRD areas were associated with lower adjusted transplant rates among all ESRD patients (RR 0.68, 95% CI 0.66,0.70). Patients living in medium and high ESRD areas had lower transplant rates from the waiting list compared to those in low ESRD areas (medium: RR 0.68, 95% CI 0.66,0.69; high: RR 0.63, 95% CI 0.61,0.65). Geographic variation in access to kidney transplant is in part mediated by local ESRD incidence, which has implications for allocation policy development. [source] Viral Nucleic Acid Testing (NAT) and OPO-Level Disposition of High-Risk Donor OrgansAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2009L. M. Kucirka The use of Public Health Service/Centers for Disease Control and Prevention (PHS/CDC) high-risk donor (HRD) organs remains controversial, especially in light of a recent high-profile case of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) transmission. Nucleic acid testing (NAT), while more expensive and time consuming, reduces infectious risk by shortening the period between infection and detectability. The purpose of this study was to characterize HRDs and disposition of their organs by organ procurement organization (OPO), to measure NAT practices by OPO and to examine associations between NAT practices and use of HRD organs. We analyzed 29 950 deceased donors (2574 HRDs) reported to UNOS since July 1, 2004 and May 8, 2008. We then surveyed all OPO clinical directors about their use of NAT, average time to receive NAT results, locations where NAT is performed and percentage of the time NAT results are available for allocation decisions. In total, 51.7% of OPOs always perform HIV NAT, while 24.1% never do. A similar pattern is seen for HCV NAT performance, while the majority (65.6%) never perform HBV NAT. AIDS prevalence in an OPO service area is not associated with NAT practice. OPOs that perform HIV NAT are less likely to export organs outside of their region. The wide variation of current practice and the possibility that NAT would improve organ utilization support consideration for a national policy. [source] Quantifying organ donation rates by donation service areaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2005Akinlolu O. Ojo Previous measures of OPO performance based on population counts have been deemed inadequate, and the need for new methods has been widely accepted. This article explains recent developments in OPO performance evaluation methodology, including those developed by the SRTR. As a replacement for the previously established measure of OPO performance , donors per million population , using eligible deaths as a national metric has yielded promising results for understanding variations in donation rates among the donation service areas assigned to each OPO. A major improvement uses "notifiable deaths" as a denominator describing a standardized maximal pool of potential donors. Notifiable deaths are defined as in-hospital deaths among ages 70 years and under, excluding certain diagnosis codes related to infections, cancers, etc. A most proximal denominator for determining donation rates is "eligible deaths," which includes only those deaths meeting the criteria for organ donation upon initial assessment. Neither measure is based on the population of a geographic unit, but on restricted upper limits of deaths that could be potential donors in any one locale (e.g., hospital or OPO). The inherent strengths and weaknesses of metrics such as donors per eligible deaths, donors per notifiable deaths, and number of organs per donor are discussed in detail. [source] CMS oversight, OPOs and transplant centers and the law of unintended consequencesCLINICAL TRANSPLANTATION, Issue 6 2009Richard J. Howard Abstract:, The Health Resources and Services Administration launched collaboratives with the goals of increasing donation rates, increasing the number of organs transplanted, eliminating deaths on the waiting list and improving outcomes. The Center for Medicare and Medicaid Services (CMS) recently published requirements for organ procurement organizations (OPOs) and transplant centers. Failure to meet CMS performance measures could result in OPOs losing their service area or transplant centers losing their CMS certification. CMS uses analyses by the Scientific Registry of Transplant Recipients (SRTR) to evaluate a transplant center's performance based on risk-adjusted outcomes. However, CMS also uses a more liberal (one-sided) statistical test rendering more centers likely to qualify as low performing. Furthermore, the SRTR model does not incorporate some important patient variables in its statistical model which may result in biased determinations of quality of care. Cumulatively, there is much unexplained variation for transplant outcomes as suggested by the low predictive ability of survival models compared to other disease contexts. OPOs and transplant centers are unlikely to quietly accept their elimination. They may take certain steps that can result in exclusion of candidates who might otherwise benefit from transplantation and/or result in fewer transplants through restricted use of organs thought to carry higher risk of failure. CMS should join with transplant organizations to ensure that the goals of the collaborative are not inhibited by their performance measures. [source] A heterogeneous-network aided public-key management scheme for mobile ad hoc networksINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 1 2007Yuh-Min Tseng A mobile ad hoc network does not require fixed infrastructure to construct connections among nodes. Due to the particular characteristics of mobile ad hoc networks, most existing secure protocols in wired networks do not meet the security requirements for mobile ad hoc networks. Most secure protocols in mobile ad hoc networks, such as secure routing, key agreement and secure group communication protocols, assume that all nodes must have pre-shared a secret, or pre-obtained public-key certificates before joining the network. However, this assumption has a practical weakness for some emergency applications, because some nodes without pre-obtained certificates will be unable to join the network. In this paper, a heterogeneous-network aided public-key management scheme for mobile ad hoc networks is proposed to remedy this weakness. Several heterogeneous networks (such as satellite, unmanned aerial vehicle, or cellular networks) provide wider service areas and ubiquitous connectivity. We adopt these wide-covered heterogeneous networks to design a secure certificate distribution scheme that allows a mobile node without a pre-obtained certificate to instantly get a certificate using the communication channel constructed by these wide-covered heterogeneous networks. Therefore, this scheme enhances the security infrastructure of public key management for mobile ad hoc networks. Copyright © 2006 John Wiley & Sons, Ltd. [source] Residential Provision for Adult Persons with Intellectual Disabilities in IrelandJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 2 2007Fiona Mulvany Background, The type of accommodation provided for persons with an intellectual disability is a major indicator of the social policy for this client group. This is likely to vary within and across countries; hence the importance of undertaking national and international comparisons. Estimations of future need are also required to assist service planning. Method, A database of all persons in receipt of intellectual disability services has been operating in the Republic of Ireland since 1995. In Northern Ireland, regional databases were used to provide similar information. Results, Around 10 000 people live in some form of residential provision: 56% in special settings, 35% in ordinary housing and 9% in hospitals. Most residents were classed as having ,severe' disabilities and were aged over 35 years. There were marked differences in the amount and type of provision provided in the two parts of the island. This was also mirrored in differences across health service areas within each country. The demand for future places was greater in Northern Ireland. Conclusions, A planning target of 3.5 places per 1000 adult population is proposed although substantial investments in services is required to achieve this. Longitudinal surveys are an important way of monitoring the impact of new policy initiatives. [source] Modeling the Mental Health Workforce in Washington State: Using State Licensing Data to Examine Provider Supply in Rural and Urban AreasTHE JOURNAL OF RURAL HEALTH, Issue 1 2006Laura-Mae Baldwin MD ABSTRACT:,Context: Ensuring an adequate mental health provider supply in rural and urban areas requires accessible methods of identifying provider types, practice locations, and practice productivity. Purpose: To identify mental health shortage areas using existing licensing and survey data. Methods: The 1998-1999 Washington State Department of Health files on credentialed health professionals linked with results of a licensure renewal survey, 1990 US Census data, and the results of the 1990-1992 National Comorbidity Survey were used to calculate supply and requirements for mental health services in 2 types of geographic units in Washington state,61 rural and urban core health service areas and 13 larger mental health regions. Both the number of 9 types of mental health professionals and their full-time equivalents (FTEs) per 100,000 population measured supply in the health service areas and mental health regions. Findings: Notable shortages of mental health providers existed throughout the state, especially in rural areas. Urban areas had 3 times the psychiatrist FTEs per 100,000 and more than 1.5 times the nonpsychiatrist mental health provider FTEs per 100,000 as rural areas. More than 80% of rural health service areas had at least 10% fewer psychiatrist FTEs and nonpsychiatrist mental health provider FTEs than the state ratio (10.4 FTEs per 100,000 and 306.5 FTEs per 100,000, respectively). Ten of the 13 mental health regions were more than 10% below the state ratio of psychiatrist FTEs per 100,000. Conclusions: States gathering a minimum database at licensure renewal can identify area-specific mental health care shortages for use in program planning. [source] Geographic Variation in Organ Availability Is Responsible for Disparities in Liver Transplantation between Hispanics and CaucasiansAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2009M. L. Volk The aims of this study were to determine whether disparities in waiting list outcomes exist for Hispanics and African Americans during the post-MELD era, and to investigate interactions between disparities and geography. Scientific Registry of Transplant Recipients data were used to compare Hispanics and African Americans to Caucasians listed between 2003 and 2008. Endpoints included (i) receipt of a liver transplant and (ii) death or removal from the waiting list for being too sick or medically unsuitable. Adjustment for possible confounders was performed using multivariate Cox regression, with adjustment for geographic variation using a fixed-effects multilevel model. In multivariate analysis, African Americans have similar hazard of transplantation and death/removal as Caucasians during the post-MELD era. However, Hispanics are less likely to receive a transplant than Caucasians despite adjustment for potential confounders (HR 0.80, 95% CI 0.77,0.83), while having a similar hazard of death/removal. This effect disappeared after adjusting for unequal regional distribution of Hispanics, who represent 8% of patients in donation service areas (DSAs) having median waiting times of ,155 days versus 19% in DSAs with median waiting times of >155 days. In conclusion, disparities in liver transplantation exist for Hispanics during the post-MELD era, caused by geographic variation in organ availability. [source] Organ Donation and Utilization in the United States: 1998,2007AMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2009J. E. Tuttle-Newhall Organ transplantation remains the only life-saving therapy for many patients with organ failure. Despite the work of the Organ Donation and Transplant Collaboratives, and the marked increases in deceased donors early in the effort, deceased donors only rose by 67 from 2006 and the number of living donors declined during the same time period. There continues to be increases in the use of organs from donors after cardiac death (DCD) and expanded criteria donors (ECD). This year has seen a major change in the way organs are offered with increased patient safety measures in those organ offers made by OPOs using DonorNet©. Unfortunately, the goals of 75% conversion rates, 3.75 organs transplanted per donor, 10% of all donors from DCD sources and 20% growth of transplant center volume have yet to be reached across all donation service areas (DSAs) and transplant centers; however, there are DSAs that have not only met, but exceeded, these goals. Changes in organ preservation techniques took place this year, partly due to expanding organ acceptance criteria and increasing numbers of ECDs and DCDs. Finally, the national transplant environment has changed in response to increased regulatory oversight and new requirements for donation and transplant provider organizations. [source] Quantifying organ donation rates by donation service areaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2005Akinlolu O. Ojo Previous measures of OPO performance based on population counts have been deemed inadequate, and the need for new methods has been widely accepted. This article explains recent developments in OPO performance evaluation methodology, including those developed by the SRTR. As a replacement for the previously established measure of OPO performance , donors per million population , using eligible deaths as a national metric has yielded promising results for understanding variations in donation rates among the donation service areas assigned to each OPO. A major improvement uses "notifiable deaths" as a denominator describing a standardized maximal pool of potential donors. Notifiable deaths are defined as in-hospital deaths among ages 70 years and under, excluding certain diagnosis codes related to infections, cancers, etc. A most proximal denominator for determining donation rates is "eligible deaths," which includes only those deaths meeting the criteria for organ donation upon initial assessment. Neither measure is based on the population of a geographic unit, but on restricted upper limits of deaths that could be potential donors in any one locale (e.g., hospital or OPO). The inherent strengths and weaknesses of metrics such as donors per eligible deaths, donors per notifiable deaths, and number of organs per donor are discussed in detail. [source] Hierarchical and Joint Site-Edge Methods for Medicare Hospice Service Region Boundary AnalysisBIOMETRICS, Issue 2 2010Haijun Ma Summary Hospice service offers a convenient and ethically preferable health-care option for terminally ill patients. However, this option is unavailable to patients in remote areas not served by any hospice system. In this article, we seek to determine the service areas of two particular cancer hospice systems in northeastern Minnesota based only on death counts abstracted from Medicare billing records. The problem is one of spatial boundary analysis, a field that appears statistically underdeveloped for irregular areal (lattice) data, even though most publicly available human health data are of this type. In this article, we suggest a variety of hierarchical models for areal boundary analysis that hierarchically or jointly parameterize,both,the areas and the edge segments. This leads to conceptually appealing solutions for our data that remain computationally feasible. While our approaches parallel similar developments in statistical image restoration using Markov random fields, important differences arise due to the irregular nature of our lattices, the sparseness and high variability of our data, the existence of important covariate information, and most importantly, our desire for full posterior inference on the boundary. Our results successfully delineate service areas for our two Minnesota hospice systems that sometimes conflict with the hospices' self-reported service areas. We also obtain boundaries for the spatial residuals from our fits, separating regions that differ for reasons yet unaccounted for by our model. [source] | ||||||||||||||||