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Abstract: In previous papers, the authors developed an active control scheme based on the linear quadratic regulator (LQR) to maintain the separation distance constraints of the NASA benchmark tetrahedron constellation. Two different active control schemes were used to maintain the separation distance constraints, but one control scheme applied to every eccentricity of the NASA benchmark problem. Through this paper, the digital LQR strategy will be developed with this active control scheme to maintain the separation distance conditions of the tetrahedron constellation. The motion of a pair of satellites in an elliptical orbit about the Earth is defined by the linearized Tschauner–Hempel (TH) equations. These equations will be defined discretely in the true anomaly angle for the development of the digital control scheme. In summary, the digital LQR approach will be implemented and studied to determine how this active control scheme maintains the separation distance constraints for different specific sizes of the NASA benchmark tetrahedron constellation. [Copyright &y& Elsevier]

Abstract: This paper summarizes three micro-satellite impact tests completed in early 2007 through collaboration between Kyushu University and the NASA Orbital Debris Program Office. The previous experiments completed in late 2005 aimed to compare low- and hypervelocity impacts on identical target micro-satellites, whereas the new tests used larger micro-satellites as targets and aimed to investigate the effects of impact directions. Three identical micro-satellites equipped with fully functional electronic devices were prepared as targets. Their dimensions were 20cm by 20cm by 20cm, and the mass of each was approximately 1.3kg. Aluminum alloy solid spheres, with a diameter of 3cm and a mass of 39g, were prepared as projectiles. The impact velocity was approximately 1.7km/s. The impact tests were carried out using the two-stage light gas gun at the Kyushu Institute of Technology. All target micro-satellites were completely fragmented, but there were noticeable differences among the three sets of fragments due to the different impact directions. More than 1000 fragments from each test were collected, measured, photographed, and documented with material descriptions. Preliminary results of the new data and comparisons with the previous data will be presented in the paper. [Copyright &y& Elsevier]

Abstract: This paper examines the usefulness of metaphors by comparing the assessments of the current economic conditions of the US and Japan made by the countries’ respective monetary policy authorities. In particular, this paper compares the role played by metaphors in creating a technical lexicon for business cycle phases in each language, and presents three main empirical findings. First, in both the US and Japan, metaphors are used in keeping with the business cycle phases with which each economy is faced. Second, many of the verbal, adjectival and adverbial terms can be attributed solely to the mechanical metaphor in the US, while there is no incidence of this use in the case of Japan. Third, there are more metaphoric adjectives or adverbs in the assessments of the US economy than in those of the Japanese economy. These empirical findings can be useful for second language instruction in economics. [Copyright &y& Elsevier]

Proposals being considered by the U.S. Congress would establish a cap-and-trade system to cut greenhouse gas (GHG) emissions approximately 2% annually through 2050. Past cap-and-trade policies for other pollutants have distributed allowances free to the regulated companies, leaving consumers uncompensated for passed-through costs needed to achieve the required reductions. Social equity concerns were not a major issue because the total costs were relatively small. However, Americans currently spend about $1 trillion/year on energy, directly and indirectly via the goods and services they consume. If a cap on carbon emissions results in significant increases in energy prices, social equity concerns could quickly dominate the debate over climate policy. This paper confirms earlier studies that a traditional cap-and-trade policy is regressive and would cause the cost of reducing GHG emissions to fall disproportionately on low income households. This paper explores ways to ameliorate those effects, using highly disaggregated data available on consumer expenditures and energy-input¿output analyses of the U.S. economy. Emissions are estimated based on direct and embodied energy use at the household level. Social equity concerns are taken into account and the consequences of cap-and-trade policies are assessed by quantifying the extent to which the expenditure patterns of the poor are significantly more energy intensive than those of the rich. [Copyright &y& Elsevier]

The occurrence and impact of fructose in the American food supply has garnered much recent attention in the popular press as well as the scientific community. This paper provides an overview of a workshop cosponsored by the International Life Sciences Institute North America and the USDA, Agricultural Research Service, titled "State of the Science on Dietary Sweeteners Containing Fructose." Papers in the workshop addressed the chemical composition and properties of dietary sweeteners that contain fructose, the sources and amount of fructose in the American diet, and the metabolism of fructose in the human body. Further, the authors of each paper assessed the strength of the existing data linking dietary fructose intake and risk for overweight, metabolic syndrome, type 2 diabetes mellitus, cardiovascular disease, and other disorders. The assessment considered factors in study design, including the amount fed, the food form, the length of the study, the characteristics of the subjects, the specific methodology, and other potential confounders including diet. In addition to papers assessing the basic science of fructose, some papers also addressed consumer concern about sugars and fructose in the diet, the way fructose and other sugars are presented in the media, and the resulting confusion of consumers about fructose and other sugars in the diet. The purpose of the papers in the aggregate was to clarify what data exist about fructose and what the gaps are in the data and to help both scientists and consumers understand issues surrounding fructose in the food supply. [ABSTRACT FROM AUTHOR]

Abstract: The NASA Orbital Debris Engineering Model, ORDEM2000, is in the process of being updated to a new version: ORDEM2008. The data-driven ORDEM covers a spectrum of object size from 10μm to greater than 1m, and ranging from LEO (low Earth orbit) to GEO (geosynchronous orbit) altitude regimes. ORDEM2008 centimeter-sized populations are statistically derived from Haystack and HAX (the Haystack Auxiliary) radar data, while micron-sized populations are estimated from shuttle impact records. Each of the model populations consists of a large number of orbits with specified orbital elements, the number of objects on each orbit (with corresponding uncertainty), and the size, type, and material assignment for each object. This paper describes the general methodology and procedure commonly used in the statistical inference of the ORDEM2008 LEO debris populations. Major steps in the population derivations include data analysis, reference-population construction, definition of model parameters in terms of reference populations, linking model parameters with data, seeking best estimates for the model parameters, uncertainty analysis, and assessment of the outcomes. To demonstrate the population-derivation process and to validate the Bayesian statistical model applied in the population derivations throughout, this paper uses illustrative examples for the special cases of large-size (>1m, >32cm, and >10cm) populations that are tracked by SSN (the Space Surveillance Network) and also monitored by Haystack and HAX radars operating in a staring mode. [Copyright &y& Elsevier]

Abstract: Nitrogen in wastewater degrades aquifer and surface water quality. To protect water quality in the United States, nitrogen discharge standards are strict: typically 1.0mg/L NH4-N for discharge to surface water and 10mg/L total nitrogen (TN) for discharge to soil. Passive constructed wetland treatment systems cannot meet the nitrification standards discussed in this paper, using loading rates commonly considered to be cost-effective based on economic conditions in North America. Although partial nitrification can be achieved with some vertically or intermittently loaded, subsurface flow (SSF) wetlands, complete nitrification cannot be achieved in these passive wetland treatment systems. Engineered wetlands (EWs) use mechanical power inputs via pumping of air or water to nitrify wastewater, and have evolved in large part to nitrify wastewater. The design energy requirements for these power inputs have yet to be described in the wetland treatment literature. Our paper investigates the energy and area requirements of three wetland technologies: aerated subsurface flow, tidal flow, and pulse-fed wetland treatment, compared to a mechanical activated-sludge treatment system. [Copyright &y& Elsevier]

Abstract: The following is a white paper (adapted here for print) for the U.S. National Research Council''s committee on Challenges and Opportunities in Earth Surface Processes, drafted at a National Science Foundation sponsored workshop associated with the 38th Binghamton Geomorphology Symposium, “Complexity in Geomorphology,” held at Duke University in October 2007. [Copyright &y& Elsevier]

Abstract: High strength woven fabrics are ideal candidate materials for use in structural systems where high energy absorption is required. One of the more widely used applications for woven fabrics is in propulsion engine containment systems. In this first part of a two-part paper, details of the experiments to characterize the behavior of dry fabrics including Kevlar® and Zylon® are presented. The experimental program to characterize the behavior of 1420 Denier Kevlar® 49 17×17, 500 Denier Zylon® AS 35×35, and 1500 Denier Zylon® 17×17 are discussed. The primary objective is to use the experimental results in the development of a constitutive model that can be used in an explicit finite element analysis program. These include Tension Tests in both the warp and fill directions of the fabric, Trellising Shear Tests and Friction Tests between fabric layers. The results from these tests provide the basis for development of the constitutive model – relating stresses to strains, characterizing failure and interaction between fabric layers. In addition to these basic material tests, tests on systems built with fabric wraps were also conducted. Ballistic tests of containment wraps subjected to a high velocity projectile were carried out at NASA-Glenn Research Center. While these tests provide a comparison between the energy absorbing characteristics of the three fabrics, they also provide benchmark results to validate the developed finite element methodology discussed in the second part of this paper. [Copyright &y& Elsevier]

Abstract: Aeroelastic coefficients (flutter derivatives) of bridge decks are routinely extracted from wind tunnel section model experiments for the assessment of performance against wind loading. Two distinct methods, developed over the years, are usually employed for this purpose (free or forced vibration). Even though advantages and disadvantages of each technique have been highlighted by numerous researchers, few examples of a systematic comparison of the experimental results are available in the literature. The significance of this study is related to the evaluation of an extended set of experimental data on flutter derivatives, and includes the analysis and interpretation of the differences recorded through the two methods. The motivation for this work emerged from the United States–Japan Benchmark Study on Bridge Flutter Derivatives that Iowa State University (ISU) in the United States and the Public Works Research Institute (PWRI) in Japan, initiated in 2002. Tests were designed to cover a wide range of solid cross sections, from bluff (rectangular prisms) to streamlined, in particular considering the current trend of engineers to use aerodynamically-designed girders for bridges with longer spans. In this paper, a systematic analysis and a comparison of laboratory results of flutter derivatives obtained at both institutions were performed. In a companion paper, a sensitivity study was performed to examine the implications of the perceived dissimilarities among flutter-derivative data sets on the aeroelastic instability of long-span bridges (single-mode and coupled-mode). [Copyright &y& Elsevier]

To predict atmospheric conditions in an urban environment, the land surface processes must be accurately described through the use of detailed land use (LU) and land cover (LC) data. Use of the U.S. Geological Survey (USGS) 25-category data, currently in the Fifth-generation Mesoscale Model (MM5), with the Noah land surface model (LSM) and MRF (medium-range forecast) planetary boundary layer (PBL) schemes resulted in the over-prediction of daytime temperatures in the Houston downtown area due to the inaccurate representation as a completely impervious surface. This bias could be corrected with the addition of canopy water in the urban areas from the evapotranspiration effects of urban vegetation. A more fundamental approach would be to utilize an LULC dataset that represents land surface features accurately. The Texas Forest Service (TFS) LULC dataset established with the LANDSAT satellite imagery correctly represents the Houston–Galveston–Brazoria (HGB) area as mixtures of urban, residential, grass, and forest LULC types. This paper describes how the Noah LSM and PBL schemes in the MM5 were modified to accommodate the TFS-LULC data. Comparisons with various meteorological measurements show that the MM5 simulation made with the high resolution LULC data improves the boundary layer mixing conditions and local wind patterns in the Houston Ship Channel, which is a critically important anthropogenic emission area affecting the HGB air pollution problems. In particular, when the synoptic flows are weak, the improved LULC data simulates the asymmetrically elongated Houston heat island convergence zone influencing the location of the afternoon Gulf of Mexico sea-breeze front and the Galveston Bay breeze flows. This paper is part I of a two-part study and focuses on the meteorological simulation. In part II, effects of using the different meteorological inputs on air quality simulations are discussed. [Copyright &y& Elsevier]

Abstract: This paper analyzes the evolution of African American entrepreneurship by comparing the patterns of development of African American entrepreneurship and immigrant entrepreneurship. Whereas most literature focuses on African American culture as the reason for limited entrepreneurial success compared to certain immigrant groups, this paper examines how social, economic, and political forces have adversely influenced the development of Black entrepreneurship compared to various immigrant groups. Using 90 years of census data, we also find empirical support consistent with our assertion that many immigrants have resources (not available to native non-Whites) that facilitate entrepreneurship. [Copyright &y& Elsevier]

Abstract: The protective properties of organic coated galvanised steel for outdoor applications are generally evaluated by means of accelerated laboratory tests, including electrochemical techniques. An open question is how these accelerated tests can be correlated with natural exposure in different environments. It is well known that many papers did not found any significant correlation between the natural exposure and laboratory tests. In this paper we propose a different approach. The starting point is the consideration to define the natural weathering by monitoring a few different environmental parameters affecting the organic coatings properties (energy from UV radiation, wet time, temperature, etc.), and not just considering the time of exposure. We studied two different galvanised materials: Zn and Zn–Al coatings, three different primers and one top coat. The samples were exposed for 12 months in three different natural environments: Trento (Italy), alpine region, Marseille (France) by the Mediterranean sea and Daytona (USA), a humid tropical environment. At the same time all the meteorological parameters were collected. The coatings weathering was evaluated in the laboratory after some different accelerated tests (salt spray chamber, UV exposure, cyclic test) and after natural exposure. A correlation between the “natural stresses” and the “artificial stresses” was investigated. [Copyright &y& Elsevier]

Abstract: This paper summarizes two new satellite impact experiments. The objective of the experiments was to investigate the outcome of low- and hyper-velocity impacts on two identical target satellites. The first experiment was performed at a low-velocity of 1.5km/s using a 40-g aluminum alloy sphere. The second experiment was performed at a hyper-velocity of 4.4km/s using a 4-g aluminum alloy sphere. The target satellites were 15cm×15cm×15cm in size and 800g in mass. The ratios of impact energy to target mass for the two experiments were approximately the same. The target satellites were completely fragmented in both experiments, although there were some differences in the characteristics of the fragments. The projectile of the low-velocity impact experiment was partially fragmented while the projectile of the hyper-velocity impact experiment was completely fragmented beyond recognition. To date, approximately 1500 fragments from each impact experiment have been collected for detailed analysis. Each piece has been weighed, measured, and analyzed based on the analytic method used in the NASA Standard Breakup Model (2000 revision). These fragments account for about 95% of the target mass for both impact experiments. Preliminary analysis results will be presented in this paper. [Copyright &y& Elsevier]

Abstract: In this paper, a brief history is presented of the development of pollution prevention (P2) programs and policies in both the states and by the federal government in the United States. Current trends are then discussed including the evolution of these programs, difficulties maintaining public support and prospects for the future. The 13 papers in this issue are then briefly described. They are grouped in the following four categories: [•] Government initiatives to increase use of P2 strategies and technologies [•] Purchasing initiatives [•] Sector initiatives [•] Program evaluation and measurement The papers in this issue are representative of much larger activities in each of these categories. Most P2 activity occurs in the states and by the private sector. With the available space it is not possible to adequately represent everything that is going on in all its aspects, including academia. For the future, three grand challenges are described: maintaining public support, competing priorities affecting P2 implementation by businesses, and the challenges of documenting P2 progress. [Copyright &y& Elsevier]

Abstract: This paper documents over 20 years of progress in the United States to advance environmental protection through pollution prevention and other performance-based initiatives and regulations. This paper highlights a number of different approaches and strategies used at the state and federal government levels while outlining emerging barriers to the overall effectiveness of the existing US environmental protection system. As a result, the authors provide specific recommendations to accelerate the use and evolution of performance-based initiatives and regulations to achieve the goal of sustainable consumption and production systems. [Copyright &y& Elsevier]

Abstract: As coastal disasters become more frequent and costly, a full assessment of costs becomes more important. This paper aims to identify costs of coastal disasters to human, social, built and natural capital and their associated services at the local site of a disaster and in the regions and nations that respond for relief and recovery. The spatial and temporal magnitude and scale of costs is captured differently in typical cost accounting and a more comprehensive approach, full-cost accounting. The difference between these approaches will be demonstrated using Hurricane Katrina (2005) as a case study, though we do not attempt to perform a full-cost accounting of this actual event. We examine how disaster planning and preparedness becomes more cost effective when the full cost of disasters is calculated. A full-cost accounting of coastal disasters sets the stage for rigorous comparisons of strategies for post-disaster development. The rudimentary analysis of this paper indicates that continued population development as well as the maintenance of current settlements in particular regions along the coasts may not be in the national interest. In this way, full-cost accounting could help reduce vulnerability to future disasters. [Copyright &y& Elsevier]

There are many sources of uncertainty in modelling systems including uncertainty due to parameter estimations, input data and structure of the system. In this paper, modelling system structure is understood to be the algorithms and equations used to describe and calculate processes. Specific attention is given to the uncertainty in the equations, which link models interactively in a modelling system and algorithms, which pass information between the models. This paper places emphasis on structural uncertainty in modelling systems since this topic has received very little attention in research compared to the wealth of literature on parameter and input data uncertainty. This imbalance is partly due to the difficulty in quantifying structural uncertainty and an example is given showing how this may be done. The modelling system used for this study incorporates the coupling of three models from the WASP5 package (Water quality Analysis Simulation Program) developed by the US Environmental Protection Agency: DYNHYD (hydrodynamics), EUTRO (dissolved oxygen, nutrient and phytoplankton dynamics) and TOXI (transport and transformation of sediments and micro-pollutants). The three models were coupled in the high level architecture (HLA) platform to enable interactions between the models during simulations. This platform allowed ease of implementing Monte Carlo simulation runs, which were used for the uncertainty analyses. The modelling system structure focuses on the exchange of data between EUTRO and TOXI in simulating two processes: (i) sorption of heavy metals to suspended solids as a function of the fraction of organic carbon constituting the solids and (ii) phytoplankton growth limitation by light extinction through the water column as a function of the concentration of suspended solids and chlorophyll a in the water. Both processes are described by empirical relationships using regression curves derived from field data. The variance in the y-axis interceptions of the curves (also called regression uncertainty) is taken to be the uncertainty bounds for the Monte Carlo simulations used for the uncertainty analyses. The results show that structural uncertainty can be more significant than parameter and input data uncertainty, especially if the processes are very sensitive to the state variables. [Copyright &y& Elsevier]

Abstract: This paper presents a DSP based algorithm to control inverters used in interfacing alternate energy systems with the electric utility. Since a constant and ripple free dc bus voltage is not ensured at the output of alternate energy sources, the main aim of the proposed algorithm is to make the output of the inverter immune to the fluctuations in the dc input voltage. In this paper a modified space vector pulse width modulation (SVPWM) technique is proposed which will maintain the quality of the ac output of the inverter, regardless of the ripple present at the inverter input. The principle is explained qualitatively and extensive experiments have been carried out to verify and validate the proposed algorithm. A 16-bit fixed-point C2000 family DSP from Texas Instruments was used as the controller to implement the proposed control algorithm. [Copyright &y& Elsevier]

Abstract: The Symposium on Novice Teen Driving: GDL and Beyond — Research Foundations for Policy and Practice, held in Tucson, AZ, on February 5–7, 2007, provided a detailed overview of graduated driver licensing (GDL) and other beginning driver issues in the United States. This paper summarizes the information presented at the Symposium and in its background papers. Impact on Industry: This information and summary should help all interested persons and organizations, including industry, in their efforts to improve GDL and teen driver programs in the United States, which in turn will further reduce traffic crashes and fatalities involving teenage drivers. [Copyright &y& Elsevier]

Abstract: A prototype high altitude balloon payload dedicated to measuring wind characteristics, pressure and temperature in terrestrial atmospheric environments was developed as part of a National Aeronautics and Space Administration (NASA) Workforce Development Educational Grant. The WindSat as it became known was one of 15 conceptual projects suggested by various NASA agencies with this specific concept suggested by the Jet Propulsion Laboratory (JPL). The WindSat project was designed, built, and tested by the University of Colorado at Colorado Springs (UCCS) Space Grant program to determine the feasibility of obtaining atmospheric weather in the upper and lower atmosphere for entry, descent, and landing of planetary missions. In the first phase of the project described in this paper, the payload was designed for and tested in the terrestrial environment of Earth. The prototype is similar to a radiosonde in function; however, the prototype logs data at a frequency of 1Hz to determine relative gusts and also records values on both ascent and descent through the atmosphere. Some preliminary results from the first two test flights of WindSat are given in this paper. [Copyright &y& Elsevier]

Abstract: A physical input–output table (PIOT) provides a framework in which all the physical flows associated with an economy can be recorded. This makes it a valuable tool for environmental–economic modeling and accounting. During the 1990''s PIOTs were constructed for a number of countries. Subsequently, the PIOT and related physical supply and use tables have been taken up in the System of Environmental and Economic Accounting [UN (United Nations), 2003. System of Environmental and Economic Accounting. United Nations, New York]. This paper reviews PIOTs for the Netherlands, Germany, Denmark, Italy, Finland and the European Union. These studies applied the ‘basic’ and ‘extended’ PIOT frameworks. This paper elaborates these frameworks with packaging, residuals (wastes and emissions), recycling and stock changes, in order to create a ‘full’ PIOT. The production process of the extended and full PIOT is split into structural and auxiliary production processes. Modeling applications and ways of deriving environmentally relevant information from the full PIOT are illustrated using a numerical example. [Copyright &y& Elsevier]

Abstract: This paper uses innovation strengths indicators based on patents lodged at the US Patent and Trademark Office from 1975 to 2002: (i) to analyse trends in the patenting of pollution prevention and abatement (or anti-pollution) technologies in the USA; and (ii) to provide international rankings for the development of anti-pollution technologies. As the indicators are not directly measurable, accurate approximations are used, namely patent shares for international presence, the technological specialisation index for national priorities, and the rate of assigned patents for potential economic benefits. The findings of the paper demonstrate the clear advantage Japan and France have out of the group of the top 12 foreign countries patenting in the USA. [Copyright &y& Elsevier]

This paper aims to describe selected study sites monitored and analyzed during the DELOS project. All the selected sites are protected by Low Crested Structures (LCSs) under various environmental conditions. In the first part of the paper the characteristics of the European structures are presented and the results of the inventory are summarized with statistical comparison with LCS characteristics in the worldwide scenario (Japan and USA). In the second part a description of the sites and prototype observation of the impact of LCSs is given: a description of the site, environmental conditions and response to its construction based on existing literature and on activities performed during the project are summarized and the research results are reported. Where available observation on ecological impacts and socioeconomic effects are provided. The descriptions are introductory to other DELOS Special Issue papers dealing with prototype observations and experiments. The geometric characteristics of the sites are very wide-ranging: deeply submerged LCSs perform well when groins are present (Pellestrina), whereas for semi-submerged LCSs (Lido di Dante) particular maintenance has to be planned for vulnerable parts, such as gaps and roundheads, where strong currents are responsible for erosion. Emergent LCSs show the formation of salients (Altafulla) or tombolos (Lønstrup) depending on the shoreline distances. In macro-tidal beaches (Elmer) tidal currents can control the salient development and the overall performance of the scheme. On the basis of the field observations described here, LCSs seem to work effectively under different environmental conditions, providing the opportunity to protect beaches in the context of Integrated Coastal Management. [Copyright &y& Elsevier]

Abstract: Ecological patents have been increasing steadily over time. This paper analyses trends and volatility in ecological patents in the USA from 1975 to 1997. Germany contributed more than 10% of the total US ecological patents, and is by far the strongest foreign performer. This paper estimates a set of novel regime-switching models to investigate the time-varying nature of the conditional mean, as well as the conditional variance of the patent ratio, namely the ratio of US ecological patents to total US patents, using monthly data from January 1975 to December 1997. The regime-switching LSTAR-GARCH model is found to be optimal for modelling the ecological patent ratio. [Copyright &y& Elsevier]

Abstract: Recent studies regarding the climate variability in South America during the 20th century, revealed the existence of climate cycles that influenced the hydrologic conditions in the Paraná River basin, one of the largest in the continent. How that variability affected the channel morphology of this river in its middle reach is quantitatively analyzed in this paper. The link between climate, hydrology and channel morphology is obtained through the computation of effective discharge. This discharge implicitly synthesizes the point hydrologic and bed sediment transport changes in an alluvial stream during a relatively long period. The results were obtained studying, with increasing detail, two channel reaches 373 km and 25 km long, respectively. The analysis involved the processing of more than 180 bathymetric charts, satellite images and hydraulic and sedimentologic data recorded in the Paraná River since the very beginning of the 20th century. A rather detailed description of the treatment made with this information is given in the paper. It is shown that three periods of different effective discharges fairly well correlated with reported climatic fluctuations occurred during the last 100 years, i.e. two periods of high discharges (at the century beginning and from 1970 till present) and another of relatively low discharges between 1930 and 1970. Morphologic parameters of the main channel, such as mean width, thalweg sinuosity, braided index and aspect ratio, increased or decreased in correspondence with those variations. In transitional channels (between meandering and braided) like the Paraná River, careful study of the thalweg behavior is a key issue, if a proper approach to the dynamic of morphologic processes operating on the whole channel is intended. Finally, on the basis of theoretical (extreme hypotheses approach) and empirical results, it is suggested that the Paraná River main channel would not be adjusted to the present high values of effective discharge. Thus, larger erosion of banks (channel widening) and increases in the other cited morphologic characteristics will occur if those values persist. [Copyright &y& Elsevier]

Abstract: This paper summarizes results from two postmission disposal (PMD) parametric analyses based on the high fidelity NASA orbital debris evolutionary model LEGEND. The first analysis includes a non-mitigation reference scenario and four test scenarios, where the mission lifetimes of spacecraft are set to 5, 10, 20, and 30years, respectively, before they are moved to the 25-year decay orbits. The comparison among the five scenarios quantifies how a prolonged spacecraft mission lifetime decreases the effectiveness of the 25-year decay rule in the low Earth orbit region (LEO). The second analysis includes three 25-year decay PMD scenarios where the mission lifetimes of spacecraft are set to 5years but with disposal success rates set to 50%, 70%, and 90%, respectively. It illustrates how the PMD success rate impacts the long-term debris environment. The conclusion of this paper is that a prolonged spacecraft mission lifetime and a lower PMD success rate can have noticeable negative impact on the debris environment in the long run. [Copyright &y& Elsevier]

Abstract: This paper presents a fragility assessment for roof sheathing in light frame constructions built in high wind regions. A fragility methodology is developed to assess the performance of roof sheathing subjected to uplift (suction) pressures. The majority of single-family housing in the United States is woodframe construction. A review of the performance of woodframe buildings after recent hurricanes has shown that the majority of wind damage (insured losses) was the result of a breach in the building envelope. Loss of roof sheathing and broken windows result in water penetration causing extensive interior damage and associated property and contents losses. The aim of this study was to develop a fragility model for roof sheathing uplift using available fastener test data, recently developed wind load statistics, and a code-based approach for evaluating pressures. Five baseline structures considering different roof shapes, geographic locations, nail types, and enclosure conditions were investigated using simulation and system reliability concepts. Fragilities and complementary fragilities (or survivorship curves) of roof sheathing removal considering different levels of damage are developed as a function of basic wind speed (3 s gust wind speed at 33 ft (10 m) above the ground in open terrain). The fragility models presented in this paper can be used to develop performance-based design guidelines for woodframe structures as well as tools for condition assessment and loss estimation for use with the existing building inventory. [Copyright &y& Elsevier]

Abstract: The determination of sex and estimation of stature are among the important aspect of forensic anthropology. These characteristics display population specific variation and therefore, need further attention for major populations of the world. The aim of this special issue is to bring together scientific papers dealing with new anthropological techniques and knowledge about populations that are least known. The present issue is composed of 12 papers by individual scientists from Germany, South Africa, India, The United States, Croatia, Spain, Poland, and Turkey. The samples, those were analyses by these authors had wide range including remains from archaeological and mass grave sites and dictatorial regimes. The papers show that still osteometry seems to be the preferred technique because they are more effective in determining sex and estimating body height. Forensic anthropology seems to be developing technique for specific population groups and increasing its ability to deal with diverse population around the world. [Copyright &y& Elsevier]

This paper discusses many aspects of “casualty expectation”, defined as the expected number of people suffering death or injury due to a spacecraft entry event, normally used when planning the end-of-life disposal of satellites. United States guidelines state a disposal via atmospheric entry should be controlled rather than uncontrolled whenever casualty expectation estimates exceed a specified limit. Since this guideline can have serious impacts on the cost, lifetime, and even the mission and functionality of a satellite, it is critical that casualty expectation (Ec) be estimated well, and decision-makers understand all assumptions and limitations inherent in the result. This paper begins with an overview of relevant United States guidelines. The equation the space industry typically uses to estimate Ec is presented, along with its sensitivity to typical assumptions, models, and initial condition uncertainties. An alternate quantity is introduced, called “probability of casualty”, or Pc. Two examples are given of both Ec and Pc estimations. Because Ec and Pc are dependent on variables with significant uncertainty, confidence in the estimates themselves can be challenged. Fortunately, a precise value is rarely needed. Results typically are well above or well below guideline limits to the extent that even if all variable values were certain, the resulting recommended course of action would not change. Ec and Pc are then ideal to use in relative analyses using a standard tool to assess compliance with guidelines. [Copyright &y& Elsevier]

The purpose of this paper is to study the impact of ISO 14001 certification on recycling performance. The research is based on a survey conducted on a sample of certified industrial companies that operate in United States. The paper reveals that companies’ recycling performance is significantly positively affected by certification. The paper also reveals that earlier certified companies experience better recycling performance than more recently certified companies. Finally, the paper shows that smaller firms experience greater improvement in recycling performance than larger firms due to ISO 14001 certification. [Copyright &y& Elsevier]

The global political structure has changed dramatically since the breakup of the former Soviet Union, and world changes have caused the United States to reprioritize its national hypersonic needs. The US Government has looked at the needs of the future, and the hypersonic aerospace plane is one of the systems included in alternative force structures. One hypersonic aerospace plane concept would involve magnetohydrodynamic (MHD) technology (i.e., the AJAX hypersonic flight vehicle concept) originally proposed by Russian scientist Vladimir Fraishtadt.This paper reports on the current progress and findings of an air-breathing horizontal takeoff and landing design concept using an MHD energy bypass injector ramjet engine being studied at MSE Technology Applications, Inc., HyperTech Concepts, and several universities for the National Aeronautics and Space Administration Langley Research Center under a Phase II Small Business Innovation Research project. The areas that are addressed in this paper include: (1) ionization required to achieve the required energy bypass, (2) utilization of a nonequilibrium model to calculate nonequilibrium engine ionization conditions, (3) hydrocarbon fuel reforming, and (4) vehicle performance and sizing. A quasi-onedimensional electromagnetic code combined with a new scramjet model, as well as other tools, were used to examine total system performance. [Copyright &y& Elsevier]

In February 2000, a detailed measurement campaign was conducted over a 9-day period within a mercury (Hg) cell chlor-alkali plant in the southeastern United States (US). The principal focus of this study was to determine the fugitive (non-ducted) airborne Hg emissions from the main production equipment located in the “cell building” during extended period operations, including maintenance events. Other Hg monitoring conducted in and around the plant also included surveys of process areas surrounding the cell building, measurement of Hg fluxes from soil and other exposed surfaces, and speciated Hg measurements of ambient air both “upwind” and “downwind” of the production area as well as the determination of Hg contained in output products and wastes. The study was a collaborative effort among scientists from the US Environmental Protection Agency, the US Department of Energy''s Oak Ridge National Laboratory, and the University of Michigan. This paper provides a description of the facility, the rationale and design of the study, and an introduction to companion papers containing the observational data. [Copyright &y& Elsevier]

Four major themes will dominate United States energy-security in the 21st century. One is the need to diversify the fuel mix (i.e., oil, natural gas, nuclear power, hydro-electricity and other renewable and alternative energy resources). Another is the need to diversify the geographic origin of energy. A third theme is conservation and energy efficiency. And the final theme is devising new ways of managing growing dependence on oil imports rather than aiming at achieving “energy independence”. This paper will examine the new frontiers of the United States’ energy security in the 21st century. It will argue that fossil fuels will continue to dominate US energy needs well into the 21st century and that the Gulf region will maintain its strategic importance for US energy security for the foreseeable future. The paper will conclude that US energy-security could be better served by devising ways of managing dependence on oil imports rather than engaging in meaningless debate over energy independence. [Copyright &y& Elsevier]

Journalists seem to treat public relations and its practitioners with contempt. However, this tension is complex and no studies have investigated the problem’s historic roots. Thus, this paper explores the perspective of “early insiders” through an historical analysis of autobiographies, biographies, and magazine articles written by and about early US newspaper reporters and editors. Results revealed six interrelated factors that contributed to the origins, persistence, and contradictions surrounding the hostility. The paper concludes with practical implications and future research directions. [Copyright &y& Elsevier]

This paper describes the development and use of a particle-tracking model to perform radionuclide-transport simulations in the unsaturated zone at Yucca Mountain, Nevada. The goal of the effort was to produce a computational model that can be coupled to the project''s calibrated 3D site-scale flow model so that the results of that effort could be incorporated directly into the Total System Performance Assessment (TSPA) analyses. The transport model simulates multiple species (typically 20 or more) with complex time-varying and spatially varying releases from the potential repository. Water-table rise, climate-change scenarios, and decay chains are additional features of the model. A cell-based particle-tracking method was employed that includes a dual-permeability formulation, advection, longitudinal dispersion, matrix diffusion, and colloid-facilitated transport. This paper examines the transport behavior of several key radionuclides through the unsaturated zone using the calibrated 3D unsaturated flow fields. Computational results illustrate the relative importance of fracture flow, matrix diffusion, and lateral diversion on the distribution of travel times from the simulated repository to the water table for various climatic conditions. Results also indicate rapid transport through fractures for a portion of the released mass. Further refinement of the model will address several issues, including conservatism in the transport model, the assignment of parameters in the flow and transport models, and the underlying assumptions used to support the conceptual models of flow and transport in the unsaturated zone at Yucca Mountain. [Copyright &y& Elsevier]

This paper presents the CN2 model for calculating the micrometeorological influences on the refractive index structure parameter. The CN2 model is a semi-empirical algorithm developed by the U.S. Army Research Laboratory to provide realistic values for the refractive index structure parameter over land given two vertical levels of conventional wind speed, temperature, and humidity data as input. The CN2 model is based on the structure function formulations of Tatarski. Equations for the real index of refraction are expressed in terms of temperature, pressure, and moisture (preferably the conserved elements potential temperature and specific humidity). Calculations of micrometeorological profile structure are carried out via Monin–Obukhov theory for the surface layer. Model results can be derived for unstable, stable, and near-neutral atmospheric conditions. The CN2 model algorithm is validated in comparison to optical scintillometer data collected at 2 m above ground level over a 450 m path. The paper reported here contains technical and user’s guide information on the CN2 model. [Copyright &y& Elsevier]

This paper presents a procedure for the evaluation of the seismic damage in steel moment frame buildings. The rotational capacities, of typical connections of a building in the Los Angeles area, which suffered extensive damage during the Northridge earthquake, were determined using stress triaxiality as an indicator for fracture. The rotational demands of the same connections were obtained from a three-dimensional finite element analysis of the building model. Comparisons of the rotational demands at several locations in the building to the rotational capacities determined by the stress triaxiality analysis showed that fracture of steel moment connections of the building are governed by the triaxiality of stresses. Based on a number of moment connections analyzed, the paper suggests a moment capacity equation for the pre-Northridge welded steel moment connections taking into account the fracture incidence due to stress triaxiality effect. The moment capacity of such connections as dictated by stress triaxiality compared favorably to FEMA-350 requirements. [Copyright &y& Elsevier]

This paper examines crisis discourse that emphasizes renewal and growth over issues of blame, responsibility, and liability. Three categories of renewal are discussed in light of the September 11, 2001 terrorist attacks. These categories include renewal based upon stakeholder commitment, commitment to correction, and core values. This paper concludes with crisis communication implications for both theory and practice. [Copyright &y& Elsevier]

This paper provides an overview of Advanced Vehicle Simulator (ADVISOR)—the US Department of Energy’s (DOE’s) ADVISOR written in the MATLAB/Simulink environment and developed by the National Renewable Energy Laboratory. ADVISOR provides the vehicle engineering community with an easy-to-use, flexible, yet robust and supported analysis package for advanced vehicle modeling. It is primarily used to quantify the fuel economy, the performance, and the emissions of vehicles that use alternative technologies including fuel cells, batteries, electric motors, and internal combustion engines in hybrid (i.e. multiple power sources) configurations. It excels at quantifying the relative change that can be expected due to the implementation of technology compared to a baseline scenario. ADVISOR’s capabilities and limitations are presented and the power source models that are included in ADVISOR are discussed. Finally, several applications of the tool are presented to highlight ADVISOR’s functionality. The content of this paper is based on a presentation made at the ‘Development of Advanced Battery Engineering Models’ workshop held in Crystal City, Virginia in August 2001. [Copyright &y& Elsevier]

Application of fiber reinforced polymer (FRP) composite plates to strengthen the capbeam of Pier 3 of East Church Street Bridge in Chemung County, New York, is discussed in this paper. Addition of a concrete wearing surface and a median barrier to the bridge superstructure increased dead load, contributing to deficiencies in moment and shear capacities of the capbeam structure. As a result, the concrete capbeam suffered flexural and shear cracking, and was considered for strengthening using bonded FRP composite plates. Service load tests were performed before and after the plates were installed, to investigate effectiveness of the strengthening system. Installation of the plates and results from the performed load tests related to flexural behavior of the beam are discussed in the paper. [Copyright &y& Elsevier]

This paper explores the relation between metaphysical commitments and the evaluation of design projects. The dialectical relation of permanence and change needs to be incorporated into current design more frequently. Any project which lacks a clear metaphysical status makes the challenge to address permanence and change more difficult. Metaphysical uncertainty also results in (a) evaluations that have no clear criteria of success and (b) a shift in the language of evaluation from objective criteria towards expressions of personal taste. The paper contains some examples and a case study of new courthouses in the USA. [Copyright &y& Elsevier]

The paper aims at exploring the viability of the Florida snail kite population under various drought regimes in its wetland habitat. The population dynamics of snail kites are strongly linked with the hydrology of the system due to the dependence of this bird species on one exclusive prey species, the apple snail, which is negatively affected by a drying out of habitat. Based on empirical evidence, it has been hypothesised that the viability of the snail kite population critically depends not only on the time interval between droughts, but also on the spatial extent of these droughts. A system wide drought is likely to result in reduced reproduction and increased mortality, whereas the birds can respond to local droughts by moving to sites where conditions are still favourable. This paper explores the implications of this hypothesis by means of a spatially-explicit individual-based model. The specific aim of the model is to study in a factorial design the dynamics of the kite population in relation to two scale parameters, the temporal interval between droughts and the spatial correlation between droughts. In the model high drought frequencies led to reduced numbers of kites. Also, habitat degradation due to prolonged periods of inundation led to lower predicted numbers of kites. Another main result was that when the spatial correlation between droughts was low, the model showed little variability in the predicted numbers of kites. But when droughts occurred mostly on a system wide level, environmental stochasticity strongly increased the stochasticity in kite numbers and in the worst case the viability of the kite population was seriously threatened. [Copyright &y& Elsevier]

Whole building life cycle assessment (WBLCA) has received significant attention from the research community in the past few years. The United States Green Building Council (USGBC) has made it an option for receiving points in version 4 of its Leadership in Energy and Environmental Design (LEED) rating system. Yet, the research described in this paper has revealed that the process of WBLCA as applied to LEED is not very well understood by building professionals. As many building professionals do not understand WBLCA, very few pursue it for their new building projects. The objective of the research described in this paper was to examine and clarify issues related to WBLCA as it applies to LEED. The paper presents a six-step process for conducting a WBLCA and use the process on a building case study for which a LEED compliant WBLCA was conducted and approved. The paper also suggests improvements to the current LEED WBLCA requirements that have the potential to further reduce the embodied energy and environmental impacts of materials used in new building projects. The ultimate goal of the research presented in the paper is to increase the building industry awareness of the WBLCA process and make it "business as usual". [ABSTRACT FROM AUTHOR]

The rise in power shutdowns triggered by severe weather due to deteriorating climate change has expedited the research in enhancing community resilience. Several researchers and policy-makers have contributed to the characterization and parameterization of energy resilience and reliability in particular, which requires accumulated and coordinated studies to underline the outcomes and reflect those in future works on grid resilience and reliability enhancement. The concept of both the resilience and reliability of the grid systems should be defined and distinguished so that the systems can be clearly comprehended, assessed, and operated to maintain flawless operation and ensure environmental sustainability. This paper meets the mentioned objectives to discuss grid resilience and reliability, their quantification metrics, and their enhancement techniques in detail. The paper also categorizes the United States into four tiers based on grid reliability and grid resilience using Monte Carlo Simulations and the discussed metrics. Two novel terminologies named resilience risk factor and grid infrastructure density are propounded in this work, which will serve as vital parameters to determine grid resilience. • Impact of natural disasters on the electricity grid is studied. • Grid resilience and reliability metrics and enhancement strategies are described. • Grid resilience and reliability of the United States are assessed. • The United States map is categorized based on grid resilience and reliability. • Resilience risk factor and grid infrastructure density are newly coined terms. [ABSTRACT FROM AUTHOR]

Our paper focuses on whether the geopolitical risk can generate a cleaner production and sustainable environment or not. It empirically investigates the geopolitical risk influence on the United States' renewable energy deployment. The United States' economy is the largest globally, and its economic, political, and military interests spread all over the contents. Thus, it could be the most frequent nation influenced by the world's geopolitical uncertainty. Our paper postulates that geopolitical risk stimulates countries to be independent and rely on renewable energy sources to reduce fossil fuel inflows' risk. We use a cointegration analysis and estimate an autoregressive distributed lag model using quarterly data (1973: q1-2020: q1). We find that geopolitical risk has a significant and positive effect on the United States renewable energy deployment. Hence, it is a driver, not a barrier to renewable energy diffusion. On the policy implication side, we expect to notice more deviations toward renewable energy technology by the United States and the other nations within the high probability of geopolitical uncertainty. Thus, geopolitical risk is expecting to enhance cleaner production and a sustainable environment. [Display omitted] • We explore the geopolitical risk effect on the US renewable energy diffusion. • The geopolitical risk stimulates nations to be dependent on their energy resources. • We employ a cointegration analysis and estimate an ARDL model using quarterly data. • The geopolitical risk has a direct significant effect on the renewable energy spread. • The geopolitical risk enhances cleaner energy technology and cleaner production. [ABSTRACT FROM AUTHOR]

Utility incentive programs are an important channel to support the deployment of energy efficiency in buildings. To date, these programs have largely been limited to single-component strategies. However, many utilities are now motivated to identify and develop multi-component system retrofits to achieve deeper energy savings, which are essential to achieving broader energy and greenhouse gas reduction goals in the buildings sector. In this paper we present the energy savings, demand reductions, and cost-effectiveness of 16 systems retrofit packages in six utility regions in the United States. These results are being used by these utilities to inform and develop incentive programs for systems retrofits. Our analysis shows that packages with proven lighting and HVAC measures can provide 5–22% whole building annual energy savings, and 13–22% annual energy costs savings, using utility incentive program baselines (code and existing building). The packages are reasonably cost effective for replace-on-burnout but generally not for a retrofit scenario prior to end of equipment life. Demand response can increase both the energy savings and energy cost savings, further improving the cost effectiveness of these packages. We analyzed the impact of using existing building vs. code baselines for calculating savings, showing that the choice of baseline in developing utility incentive programs has a substantial impact on the attributable energy savings to a program, with significant implications for the overall viability of a program (generally savings against existing building condition are higher and improve project and program cost-effectiveness). [ABSTRACT FROM AUTHOR]

Activists and scholars increasingly blame neoliberalism for the failure to sharply reduce greenhouse gas emissions, but there is insufficient research that investigates the theoretical link between neoliberalism and climate paralysis. This paper seeks to fill that gap by presenting a coherent account of how neoliberal ideology has constrained policies to address climate change in the United States. As motivation, we first present evidence suggesting more neoliberal countries perform worse in addressing climate change. We then analyze how three tenets of neoliberal ideology—to decentralize democracy, defund public investment, and deregulate the economy—have stymied climate action in the United States. Finally, we discuss the Green New Deal as a decisively anti-neoliberal framework that seeks to wield the power of the federal government to pursue large-scale public investments and binding climate regulations for rapid decarbonization. [ABSTRACT FROM AUTHOR]

Approximately 11% of bridges in the United States are categorized as structurally deficient and there is a marked need of more accurately evaluating true structural capacity. Structural Health Monitoring (SHM) systems can provide a timely indication of the need for maintenance, repair, rehabilitation and replacement of bridges and can greatly improve the apportionment and management of limited resources. This paper presents an Automated Ambient Traffic (AAT) approach for determining load rating of bridges monitored by the BECAS SHM system under ambient traffic. The AAT approach was developed through a process integration of truck detection, bridge model calibration, and bridge load rating: (1) the quasi-static bridge strain response and the characteristics of associated trucks are collected; (2) multiple trucks are randomly sampled from a historic Weigh-In-Motion (WIM) database; and (3) for each combination of strain response and truck selection, an Finite Element (FE) model is calibrated and used to calculate a load rating. Sampling strategies were discussed for appropriately quantifying the influence of uncertainties of truck characteristics on the calibration and load rating results. To demonstrate this approach, a sample three-span, five-girder, and two-lane steel girder/concrete deck (I-80) bridge was utilized. A load rating of the I-80 Bridge using the Traditional Known Truck (TKT) approach was performed to provide benchmark results. The results of the calibration and load rating using the AAT approach were derived using three different sampling strategies and compared to those using the TKT approach. The sampling strategy, selecting strain response with a spectrum of higher peak girder strains, associated trucks with a spectrum of higher gross vehicle weights, and two truck events on south and north lanes respectively for a calibration, resulted in the best calibration and load rating results. It was concluded that the AAT approach using the BECAS SHM system is a reliable method for continuously estimating the load carrying capacity of bridges. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke (AIS) is the leading cause of disability worldwide and among the leading causes of mortality. Although intravenous tissue plasminogen activator (IV-rtPA) was approved nearly 2 decades ago for treatment of AIS, only a minority of patients receive it due to a narrow time window for administration and several contraindications to its use. Endovascular approaches to recanalization in AIS developed in the 1980s, and recently, 5 major randomized trials showed an overwhelming superior benefit of combining endovascular mechanical thrombectomy with IV-rtPA over IV-rtPA alone. In this paper, we discuss the evolution of catheter-based treatment from first-generation thrombectomy devices to the game-changing stent retrievers, results from recent trials, and the evolving stroke systems of care to provide timely access to acute stroke intervention to patients in the United States. [ABSTRACT FROM AUTHOR]