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Hydrocarbon polymers are used in a wide variety of practical applications. In the field of dynamic compression at extreme pressures, these polymers are used at several high energy density (HED) experimental facilities. One of the most common polymers is poly(methyl methacrylate) or PMMA, also called Plexiglass® or Lucite®. Here, we present high-fidelity, hundreds of GPa range experimental shock compression data measured on Sandia’s Z machine. We extend the principal shock Hugoniot for PMMA to more than threefold compression up to 650 GPa and re-shock Hugoniot states up to 1020 GPa in an off-Hugoniot regime, where experimental data are even sparser. These data can be used to put additional constraints on tabular equation of state (EOS) models. The present results provide clear evidence for the need to re-examine the existing tabular EOS models for PMMA above ∼120 GPa as well as perhaps revisit EOSs of similar hydrocarbon polymers commonly used in HED experiments investigating dynamic compression, hydrodynamics, or inertial confinement fusion.

Large-scale material extrusion additive manufacturing technology is becoming the new mainstream technology for scaled-up composite mold and die applications. This paradigm shift in composite processing technology is primarily driven by out-of-autoclave tooling applications, in which fiber reinforced composite molds with scaled-up sizes and embedded heating elements are attractive. The present research describes the design, manufacturing, and testing of self-heating composite molds fabricated via a large-scale pellet extrusion 3D printing machine with an integrated wire co-extrusion tool. Polycarbonate (PC) composites reinforced with carbon fiber (PC/CF; 20 wt.%) and glass fiber (PC/GF; 20 wt.%) were used to fabricate mold parts. Joule heating thermal test results showed that uniform temperatures (~100 °C) were achieved for both PC/CF and PC/GF mold surfaces, using a custom-made feedback control power supply and infrared thermography. Mechanical characterizations, including tensile and flexural testing were performed on the wire-embedded and un-wired PC/CF and PC/GF base specimens to investigate the impact of the fiber reinforcement as well as the embedded wires. In the direction of extrusion, the ultimate tensile stress of PC/CF was 105 MPa, and that of PC/GF was 73 MPa, while the neat PC value was 64 MPa. Inner-bead voids and interfacial gaps were observed and characterized via optical and scanning electron microscopy. The embedded wires and inner bead impacted the mechanical properties of the composites. However, the stiffness of the wire-embedded mold was still satisfactory, proving that the technology can be used to fabricate additively manufactured out-of-oven/autoclave molds.

Aerojet Rocketdyne's NextSTEP program is developing and demonstrating a 100 kW Electric Propulsion (EP) system, the XR-100, which includes a modular power processing unit and modular xenon feed system to operate a Nested Hall Thruster (NHT) designed for powers up to 200 kW. The NextSTEP system is intended for use on large scale cargo transportation to support human missions to the Moon and Mars, which require very high-power Solar Electric Propulsion (SEP) systems operating between 200 and 400 kW. The three-year program objective is to operate the integrated EP system continuously at 100 kW for 100 hours, advancing this very high-power EP system to Technology Readiness Level (TRL) 5. In order to process the power and control propellant flow for this high-power system, Aerojet Rocketdyne has developed a modular concept for the Power Processing Units (PPUs) and Xenon feed system. The program has completed testing of critical elements of the PPU and feed system with a thruster simulator. Design upgrades to demonstrate the TRL 5 capabilities are underway. This paper will present an overview of the program and system design approach, the high power XR-100 capabilities of the PPU and feed system, and the latest test results for the 100 kW EP system demonstration program. In order to successfully execute this contract, there is a close collaboration between the teammates at Aerojet Rocketdyne (AR), the University of Michigan (UM), the NASA Jet Propulsion Laboratory (JPL), and the NASA Glenn Research Center (GRC).

This article evaluates the energy efficiency investment decisionmaking used by most organizations. A financial risk management process is shown to provide greater financial returns and less risk in selecting investment projects compared to the traditional practice of payback analysis. An example application of Energy Budgets at Risk, a value-at-risk-based energy efficiency investment analysis, is presented to illustrate the advantages of risk management analysis in evaluating energy efficiency projects. Summary risk analysis results are presented as a communication bridge between technical project engineers, chief financial officers, and other financial executives and decision-makers. The article concludes with the suggestion to expand the traditional roles of energy engineers and managers to include providing energy efficiency and budget financial risk management analysis.

This paper reviews current capital budgeting practices and their impact on energy efficiency investments. The prevalent use of short payback "rule-of-thumb" requirements to screen efficiency projects for risk is shown to bias investment choices towards "sure bet" investments bypassing many profitable efficiency investment options. A risk management investment strategy is presented as an alternative to risk avoidance practices applied with payback thresholds. The financial industry risk management tool Value-at-Risk is described and extended to provide an Energy-Budgets-at-Risk or EBaR risk management analysis to convey more accurate energy efficiency investment risk information. The paper concludes with recommendations to expand the use of Value-at-Risk-type energy efficiency analysis.

Electric utilities and regulators face difficult challenges evaluating new energy efficiency and smart grid programs prompted, in large part, by recent state and federal mandates and financial incentives. It is increasingly difficult to separate electricity use impacts of individual utility programs from the impacts of increasingly stringent appliance and building efficiency standards, increasing electricity prices, appliance manufacturer efficiency improvements, energy program interactions and other factors. This study reviews traditional approaches used to evaluate electric utility energy efficiency and smart-grid programs and presents an agent-based end-use modeling approach that resolves many of the shortcomings of traditional approaches. Data for a representative sample of utility customers in a Midwestern US utility are used to evaluate energy efficiency and smart grid program targets over a fifteen-year horizon. Model analysis indicates that a combination of the two least stringent efficiency and smart grid program scenarios provides peak hour reductions one-third greater than the most stringent smart grid program suggesting that reductions in peak demand requirements are more feasible when both efficiency and smart grid programs are considered together. Suggestions on transitioning from traditional end-use models to agent-based end-use models are provided.

Recent empirical evidence on rent and occupancy premiums associated with sustainable buildings is used to evaluate risks and returns associated with green real estate development projects. Green bu...

Developers and building owners are increasingly considering sustainable design options to enhance marketability, to meet corporate “green goals,” or simply as contributions to a more sustainable future. Regardless of motivation, the consideration of green designs is always prefaced with the question of “how much more does a sustainable design cost?” For the growing number of Leadership in Energy and Environmental Design LEED certified design professionals and others interested in promoting sustainable designs, this reluctance to accept anything other than marginal increments over least initial cost options is frustrating and, in some cases, costly. Green designs that are viewed as too “blue sky” can generate concerns that designers are less attuned to cost issues considered important by owners and developers. The irony in this situation is that many sustainable design components related to energy-efficiency investments provide returns greater than those achieved by developers/owners with other financial investments. One reason for this investment disparity is the traditional use of payback analysis to evaluate energyefficiency investments, with paybacks of two years or less often required for a project to qualify as a sustainable design option. This rule of thumb decision criterion stands in stark contrast to the sophisticated financial risk-management analysis such organizations use to assess their financial investments. This paper describes Energy Budgets at Risk EBaR Jackson 2008 , a new quantitative energy risk-management process that evaluates and presents risks and rewards associated with incremental investments in energy-related sustainability designs. EBaR analyses and presentations provide a bridge that translates energyefficiency and green designs into a financial presentation and a language familiar to CFOs and financial administrators. EBaR case study results Jackson 2008 are presented below to illustrate this process.

Electric power failures in the aftermath of disasters cripple the delivery of critical emergency services. While emergency generators are available in some facilities, these systems are designed for short-term use and support limited functions. The substantial investment required to ensure emergency power for all critical services is difficult to justify because of the uncertainty associated with the likelihood and magnitude of future disasters. Investment evaluations change when a new source of emergency power is considered. This study evaluates the costs and benefits of a program to preemptively install new building-sited electric combined heat and power (CHP) generation technologies to ensure reliable long-term power for critical municipal services in hurricane-prone regions of the US. Three municipalities are selected for this analysis: Houston, Texas; Miami, Florida; and Charleston, South Carolina. Analysis indicates that costs of such a program can, in some cases, provide net energy bill savings regardless of the occurrence of a disaster.

New, small-scale electric generation technologies permit utility customers to generate some of their own electric power and to utilize waste heat for space heating and other applications at the building site. This combined heat and power (CHP) characteristic can provide significant energy-cost savings. However, most current US utility regulations leave CHP standby rate specification largely to utility discretion resulting in claims by CHP advocates that excessive standby rates are significantly reducing CHP-related savings and inhibiting CHP diffusion. The impacts of standby rates on the adoption of CHP are difficult to determine; however, because of the characteristically slow nature of new technology diffusion. This study develops an agent-based microsimulation model of CHP technology choice using cellular automata to represent new technology information dispersion and knowledge acquisition. Applying the model as an n-factorial experiment quantifies the impacts of standby rates on CHP technologies under alternative diffusion paths. Analysis of a sample utility indicates that, regardless of the likely diffusion process, reducing standby rates to reflect the cost of serving a large number of small, spatially clustered CHP systems significantly increases the adoption of these technologies.

To compare the performance and safety of a fully subcutaneous vascular access device, the LifeSite hemodialysis access system, versus a tunneled hemodialysis catheter, the Tesio-Cath, at 1 year after implantation.Sixty-eight patients who required hemodialysis received implantation of the LifeSite device or a Tesio-Cath device as a part of this multicenter study. Thirty-four patients were treated in each group. The endpoints observed included blood flow rates and associated venous pressures, overall and device-related adverse events, the need for thrombolytic infusions, device-related infections (DRIs) and associated hospitalizations, and technical device survival.During the 12-month observation period, significantly higher venous pressures were required in patients with the Tesio-Cath to achieve blood flow rates comparable with those achieved with the LifeSite device. Patients in the LifeSite group experienced a significantly lower rate of non-device-related adverse events (P.001), device-related adverse events (P.016), need for thrombolytic infusions (P.002), and DRIs (P.013) compared with patients in the Tesio-Cath group. There was a trend toward a lower number of hospital days per month for DRIs in the LifeSite group, with the rate for the Tesio-Cath group being twice that in the LifeSite group. The use of the LifeSite device was also associated with a significantly higher probability of device survival for 12 months after censoring for planned removals (P.031).The results of the present study demonstrate superior device performance and technical device survival, reduced complications, and the need for fewer interventions with the LifeSite hemodialysis access system compared with a standard hemodialysis catheter during a 1-year time period after implantation.

Multicenter clinical trial results with the LifeSite® hemodialysis access system.BackgroundThe LifeSite® Hemodialysis Access System is a subcutaneous access device designed to maximize blood flow while minimizing access-related complications. The purpose of this study was to compare the efficacy and safety of the LifeSite System to a similar but transcutaneous access device, the Tesio-Cath® Hemodialysis Catheter.MethodsThe study was conducted in two phases. A multi-center randomized prospective design was utilized for the first phase (Phase 1) where thirty-four patients were enrolled in the Tesio-Cath group and 36 patients into the LifeSite group where 0.2% sodium oxychlorosene was used as an antimicrobial solution for the LifeSite. A nonrandomized, but otherwise identical, second phase of the study followed where a 70% isopropyl alcohol solution was utilized as the antimicrobial solution for 34 additional LifeSite patients (Phase 2).ResultsDevice function was evaluated in Phase 1 of the trial. Actual blood flow (determined by ultrasound dilution) was greater in the LifeSite versus the Tesio-Cath group (358.7 vs. 331.8 mL/min, P < 0.001 for machine-indicated blood flow of 400 mL/min). Infection comparisons were performed for all three groups encompassing Phase 1 and 2 of the trial; Tesio-Catheter, LifeSite System with oxychlorosene, and LifeSite System with 70% isopropyl alcohol. Device-related infections were defined as systemic bacteremia without another obvious site of origin and exit site infections requiring systemic antibiotics or device removal. This revealed infection rates per 1000 device use days of 1.3 for the LifeSite alcohol group, 3.3 for the Tesio-Cath group, and 3.4 per for the LifeSite oxychlorosene group. There was no statistically significant difference in device related infection rates between the Tesio-Cath and the LifeSite oxychlorosene groups. There were significant differences in infection rate between LifeSite alcohol group and the other two groups (P < 0.05). Device thrombosis was defined by the need for instillation of thrombolytic agents to maintain blood flow>300 mL/min. There was no difference in the need for thrombolytic infusions between the LifeSite oxychlorosene group and the Tesio-Cath group (P = 0.1496); however, the LifeSite alcohol group required significantly fewer thrombolytic infusions than the Tesio-Cath group (P = 0.0295) to maintain adequate blood flow. Device survival at 6 months after stratification by diabetic status and adjusting for age was significantly better in the LifeSite alcohol group (89.9%) than in the LifeSite oxychlorosene group (64.8%, P = 0.0286) and in the Tesio-Cath (69.1%, P = 0.0292) group.ConclusionsThe LifeSite Hemodialysis Access System, when used with 70% isopropyl alcohol as an antimicrobial solution, provides superior performance with a lower infection rate and better device survival than a standard cuffed tunneled hemodialysis catheter.

Preceding chapters in Future Energy present exciting advances in energy production, conversion and storage, some of which were barely on the horizon when the first edition of this reference was published in 2008. Similarly, the ‘smart grid’, which was an idea just gaining traction in 2008, reflects the most exciting paradigm change to impact the electric power system since its beginnings more than a century ago. Smart grids apply new metering, communications and control technologies and strategies to provide an optimised power system that integrates distributed energy resources and electric customer participation in maximising power system efficiency and reliability. Smart grids will also contribute to achieving energy efficiency, conservation and power plant emissions goals. While the smart grid concept can be described relatively easily, the transition to smart power grids presents financial evaluation challenges that are unique to these new technologies and applications.

Residence in a State has a very important role as human resources capable of turning the wheels of development of a nation. In managing the population administration, and its relation to the needs of the community about their rights as a resident or citizen, then the government should be running one of the essential functions, which provide public services, particularly the population administration services to meet people's rights as citizens. There are internal factors District government organization that can inhibit or support the achievement of the performance of Civil Affairs Ministry, namely: factor structure, factor culture and human resource factors.Keywords : population, administration, development

The Fistula First Breakthrough Initiative (FFBI) has improved the awareness of the value of fistula creation in patients with end-stage renal disease (ESRD). The FFBI Health Policy Workgroup has been charged with reviewing the relationship of policy and economic issues to this project. This article reviews the efforts and successes of renal community clinical activities and reemphasizes the economic impact of fistula creation and catheter reduction on the health care system. Major obstacles are discussed, and existing tools and efforts designed to address them are outlined. The FFBI Health Policy Workgroup then identifies less frequently recognized barriers to the achievement of the FFBI goals and suggests solutions to them. It concludes that nephrologists need to assume the leadership role and drive fistula creation and central venous catheter reduction to achieve programmatic success.

Fistula First, now a CMS "Breakthrough Initiative", sets the eventual goal of 66% prevalence of arteriovenous (AV) fistulas in the U.S. dialysis population. The benefit of an AVfistula as the hemodialysis access has been clearly demonstrated; yet the current incidence of AV fistulas in patients new to dialysis in the U.S. is extremely low and prevalence rates are approximately half the eventual target rate. In this article, the components of an Integrated Vascular Access Program are described. One of these is a dedicated Vascular Access Center (VAC), a facility specializing in radiographic and interventional procedures for the vascular access care of patients with ESRD. Procedures carried out in a dedicated VAC are described and are shown to support both K/DOQI and the Fistula First "Change Package" in terms of promoting increased prevalence of AV fistulas. These include preoperative vessel mapping, fistula maturation, fistula maintenance, and identification of candidates for secondary fistula. The above type procedures that were carried out in our dedicated VAC in 2004 are described. These included vessel mapping (n=220), fistula maturation procedures (n=104), and fistula maintenance procedures (n=103). The results suggest that the shift to a "fistula culture" within a dialysis practice requires a significant number of interventional procedures--both maturation and maintenance types. A dedicated VAC can efficiently carry out these procedures and is an important component of an Integrated Vascular Access Program.

A 3-year prospective study examined 76 frontal (F) and 45 lateral (L) motor vehicle crash (MVC) patients with regard to seatbelt restraint use and occupant compartment contact and intrusion injuries. These 121 MVC victims with multiple injuries (39 belted [B] and 82 non-belted [NB]), admitted to a level I trauma center, were studied by accident reconstruction and medical data analysis. They had a MVC mean impact velocity (delta V) of 30 +/- 11 mph and an injury Severity Score of 29 +/- 12. Proper restraint use reduced brain injury in F MVCs (30% FB vs. 47% FNB) but had no effect in L MVCs (63% LB vs. 30% FB [p0.06]). Belt use did not protect against lung, liver, spleen, pelvis, or lower extremity (LE) injury. These appeared to be more a function of crash direction, with LE injuries higher in F crashes (p0.04) and pelvis injuries (p0.001) higher in L crashes. In FB crashes, however, properly used safety restraints were the primary cause of bowel or colon injuries (p0.006). Belts did not prevent thoracic or abdominal solid organ injuries in L crashes. Contact-intrusions (CI) of the car occupant compartment in F crashes were the main cause of brain (A-pillar), lung and liver (steering wheel and instrument panel), and LE (toepan) injuries; but in L crashes, side-door CI caused lung, aorta, liver, and pelvic injuries. In contrast, contact-only (CO) injuries of the steering assembly were mainly responsible for injuries to the lung, heart, and liver in F crashes, and side-door CO for lung, liver, and spleen injuries in L crashes. Deaths and complications after injury were higher among F MVC occupants, or when delta V wasor = 30 mph. Hospital and professional costs reflect the complex care needed for victims of multiple injuries: FB, $99,000; FNB, $95,000; LB, $75,000; LNB, $79,000; total, $10.7 million. Present vehicle safety standards are not adequate, and structural design changes are needed to improve restraints and protect occupants from intrusion-related injuries.

This paper evaluates the impact of the US National Energy Plan on energy demand in US commercial and residential buildings. Following a brief historical review of energy use patterns in US buildings, estimates are presented of how the National Energy Plan would affect the sector in terms of fuel expenditures and investment in energy using equipment and structures. The analysis is based on economic-engineering models of energy demand which are currently being used by the US Department of Energy to evaluate conservation programmes. The demand models incorporate behavioural as well as technological determinants and are sufficiently disaggregated to allow consideration of individual components of the National Energy Plan.

This paper reviews trends in residential energy use and commercial energy use for the 1950–1975 period. Historical data on energy use by type of fuel—electricity, gas, oil, other—are presented for both sectors. These energy use data are compared with data on the determinants of energy use for each sector: population, per capita income, fuel prices, economic output from the service sectors, commercial building floorspace. These historical data show marked differences between the 1950–1972 and 1972–1975 periods. From 1950 to 1972, energy use in both sectors grew steadily and rapidly. Since 1972, however, energy use growth has been almost static and unstable. The data show, in a general way, the influence of changes in fuel prices and economic activity on energy use.

Aggressive treatment of early fistula failure. Background Fistula failure has been classified as early and late. Early failure refers to those cases in which the arteriovenous (AV) fistula never develops to the point that it can be used or fails within the first 3 months of usage. It has been common practice to abandon these early failures; however, aggressive evaluation and treatment of early fistula failures has been shown to result in the salvage of a large percentage. The two most common causes of the failure seen at this time are juxta-anastomotic stenosis (JAS) and the presence of accessory veins. Both of these can be easily diagnosed by physical examination. This study reports the results of early fistula failure managed aggressively in an attempt at salvage. Methods These studies were conducted in six freestanding outpatient interventional facilities in different regions of the United States. Interventional nephrologists are employed at all of these facilities except one that is operated by an interventional radiologist. Each patient was first evaluated angiographically to identify the anatomy of their AV fistula and detect abnormalities that might be present. Stenotic lesions were then treated with angioplasty and accessory veins thought to be significant were obliterated. All patients were then followed to determine if the fistula was usable for dialysis. Results One hundred patients were identified that met the definition of early failure. Venous stenosis was present in 78% of these cases. In 43% of the cases, the lesion was in the JAS location. In 15%, this was the only lesion present. In 24%, it was associated with an accessory vein, in 6% with a proximal stenosis, and in 4% with both. A proximal stenosis lesion was present in the fistula in 36%. In 6%, it was associated with an accessory vein, in 6% with a JAS, and in 4% with both. The definition of arterial anastomosis stenosis was met in 38% of the cases. This was always in association with JAS. In four cases, a stenotic lesion was present in the artery above the anastomosis. An accessory vein was present in 46% of the cases. In 12% of the cases, this was the only lesion present. In 24% of the cases, this anomaly was associated with JAS, in 6% with proximal stenosis, and in 4% with both. Angioplasty was performed to treat venous stenosis in 72% of the cases with a 98% success rate. Angioplasty of the arterial anastomosis was performed in 38 cases with a 100% success rate. Accessory vein obliteration was performed in 46% of the patients with a 100% success rate. The overall complication rate in this series was 4%, of these 3% were minor and 1% were major. It was possible to initiate dialysis using the fistula in 92% of the cases. Actuarial life-table analysis showed that 84% were functional at 3 months, 72% at 6 months, and 68% at 12 months. Conclusion If correctable pathology is detected in patients with early fistula failure, the incidence of correctable lesions is relatively high and an aggressive therapeutic approach can be expected to have a high yield.