bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel General and Robust Method Based on NAOP for Solving Nonlinear Ordinary Differential Equations and Partial Differential Equations by Cellular Neural Networks
Authors: Chamberlain Chedjou Jean , Kyamakya Kyandoghere
Published: May 2013

This paper develops and validates through a series of presentable examples, a comprehensive high-precision, and ultrafast computing concept for solving nonlinear ordinary differential equations (ODEs) and partial differential equations (PDEs) with cellular neural networks (CNN). The core of this concept is a straightforward scheme that we call "nonlinear adaptive optimization (NAOP),” which is used for a precise template calculation for solving nonlinear ODEs and PDEs through CNN processors. One of the key contributions of this work is to demonstrate the possibility of transforming different types of nonlinearities displayed by various classical and well-known nonlinear equations (e.g., van der Pol-, Rayleigh-, Duffing-, Rössler-, Lorenz-, and Jerk-equations, just to name a few) unto first-order CNN elementary cells, and thereby enabling the easy derivation of corresponding CNN templates. Furthermore, in the case of PDE solving, the same concept also allows a mapping unto first-order CNN cells while considering one or even more nonlinear terms of the Taylor's series expansion generally used in the transformation of a PDE in a set of coupled nonlinear ODEs. Therefore, the concept of this paper does significantly contribute to the consolidation of CNN as a universal and ultrafast solver of nonlinear ODEs and/or PDEs. This clearly enables a CNN-based, real-time, ultraprecise, and low-cost computational engineering. As proof of concept, two examples of well-known ODEs are considered namely a second-order linear ODE and a second order nonlinear ODE of the van der Pol type. For each of these ODEs, the corresponding precise CNN templates are derived and are used to deduce the expected solutions. An implementation of the concept developed is possible even on embedded digital platforms (e.g., field programmable gate array (FPGA), digital signal processor (DSP), graphics processing unit (GPU), etc.). This opens a broad range of applications. Ongoing works (as outlook) are using NAOP for deriving precise templates for a selected set of practically interesting ODEs and PDEs equation models such as Lorenz-, Rössler-, Navier Stokes-, Schrödinger-, Maxwell-, etc.
Tip-Over Stability Analysis of Mobile Boom Cranes With Swinging Payloads
Authors: Rauch Andreas , Singhose William , Fujioka Daichi , Jones Taft
Published: May 2013

Mobile boom cranes are used throughout the world to perform important and dangerous manipulation tasks. The usefulness of these cranes is greatly improved if they can utilize their mobile base when they lift and transfer a payload. However, crane motion induces payload swing. The tip-over stability is degraded by the payload oscillations. This paper presents a process for conducting a stability analysis of such cranes. As a first step, a static stability analysis is conducted to provide basic insights into the effects of the payload weight and crane configuration. Then, a semi-dynamic method is used to account for payload swing. The results of a full-dynamic stability analysis using a multibody simulation of a boom crane are then compared to the outcomes of the simpler approaches. The comparison reveals that the simple semi-dynamic analysis provides good approximations for the tip-over stability properties. The results of the stability analyses are verified by experiments. The analysis in this paper provides useful guidance for the practical tip-over stability analysis of mobile boom cranes and motivates the need to control payload oscillation.
A Multimodule Planar Air Bearing Testbed for CubeSat-Scale Spacecraft
Authors: Wilson William R. , Jones Laura L. , Peck Mason A.
Published: May 2013

In the past several years, small satellites have taken on an increasingly important role as affordable technology demonstrators and are now being viewed as viable low-cost platforms for traditional spacecraft mission objectives. As such, the CubeSat standard (1 kg in a 10 cm cube) has been widely adopted for university-led development efforts even as it is embraced by traditional spacecraft developers, such as NASA. As CubeSats begin to take on roles traditionally filled by much larger spacecraft, the infrastructure for dynamics and controls testing must also transition to accommodate the different size and cost scaling associated with CubeSats. While air-bearing-based testbeds are commonly used to enable a variety of traditional ground testing and development for spacecraft, few existing designs are suitable for development of CubeSat-scale technologies, particularly involving multibody dynamics. This work describes Cornell University's FloatCube testbed, which provides a planar reduced-friction environment for multibody dynamics and controls technology development for spacecraft less than 6 kg and a 15 cm cube. The multimodule testbed consists of four free-floating air-bearing platforms with on-board gas supplies that allow the platforms to float over a glass surface without external attachments. Each of these platforms, or FloatCubes, can host CubeSat-sized payloads at widely ranging levels of development, from prototype components to full-scale systems. The FloatCube testbed has already hosted several successful experiments, proving its ability to provide an affordable reduced-friction environment to CubeSat-scale projects. This paper provides information on the system design, cost, performance, operating procedures, and applications of this unique, and increasingly relevant, testbed.
A Finite-Deformation Mechanics Theory for Kinetically Controlled Transfer Printing
Authors: Feng Xue , Cheng Huanyu , Bowen Audrey M. , Carlson Andrew W. , Nuzzo Ralph G. , Rogers John A.
Published: May 2013

The widely used steady-state energy release rate G = F/w is extended to account for the elastic energy of deformed compliant stamps, e.g., low-modulus poly(dimethyl siloxane) (PDMS). An analytical expression for the energy release rate is obtained to quantify interfacial adhesion strength in tape peeling tests, and to analyze the dynamics of kinetically controlled transfer printing. The critical delamination velocity to separate retrieval and printing is related to the critical energy release rate and the tensile stiffness of the stamp. Experimental results validate the analytical expression established by the mechanics model.
Development of a Mechatronic Platform and Validation of Methods for Estimating Ankle Stiffness During the Stance Phase of Walking
Authors: Rouse Elliott J. , Hargrove Levi J. , Perreault Eric J. , Peshkin Michael A. , Kuiken Todd A.
Published: May 2013

The mechanical properties of human joints (i.e., impedance) are constantly modulated to precisely govern human interaction with the environment. The estimation of these properties requires the displacement of the joint from its intended motion and a subsequent analysis to determine the relationship between the imposed perturbation and the resultant joint torque. There has been much investigation into the estimation of upper-extremity joint impedance during dynamic activities, yet the estimation of ankle impedance during walking has remained a challenge. This estimation is important for understanding how the mechanical properties of the human ankle are modulated during locomotion, and how those properties can be replicated in artificial prostheses designed to restore natural movement control. Here, we introduce a mechatronic platform designed to address the challenge of estimating the stiffness component of ankle impedance during walking, where stiffness denotes the static component of impedance. The system consists of a single degree of freedom mechatronic platform that is capable of perturbing the ankle during the stance phase of walking and measuring the response torque. Additionally, we estimate the platform's intrinsic inertial impedance using parallel linear filters and present a set of methods for estimating the impedance of the ankle from walking data. The methods were validated by comparing the experimentally determined estimates for the stiffness of a prosthetic foot to those measured from an independent testing machine. The parallel filters accurately estimated the mechatronic platform's inertial impedance, accounting for 96% of the variance, when averaged across channels and trials. Furthermore, our measurement system was found to yield reliable estimates of stiffness, which had an average error of only 5.4% (standard deviation: 0.7%) when measured at three time points within the stance phase of locomotion, and compared to the independently determined stiffness values of the prosthetic foot. The mechatronic system and methods proposed in this study are capable of accurately estimating ankle stiffness during the foot-flat region of stance phase. Future work will focus on the implementation of this validated system in estimating human ankle impedance during the stance phase of walking.
In Vitro Comparison of Doppler and Catheter-Measured Pressure Gradients in 3D Models of Mitral Valve Calcification
Authors: Herrmann Tarrah A. , Siefert Andrew W. , Pressman Gregg S. , Gollin Hannah R. , Touchton Steven A. , Saikrishnan Neelakantan , Yoganathan Ajit P.
Published: May 2013

Mitral annular calcification (MAC) involves calcium deposition in the fibrous annulus supporting the mitral valve (MV). When calcification extends onto the leaflets, valve opening can be restricted. The influence of MAC MV geometry on Doppler gradients is unknown. This study describes a novel methodology to rapid-prototype subject-specific MAC MVs. Replicated valves were used to assess the effects of distorted annular-leaflet geometry on Doppler-derived, transmitral gradients in comparison to direct pressure measurements and to determine if transmitral gradients vary according to measurement location. Three-dimensional echocardiography data sets were selected for two MAC MVs and one healthy MV. These MVs were segmented and rapid prototyped in their middiastolic configuration for in vitro testing. The effects of MV geometry, measurement modality, and measurement location on transmitral pressure gradient were assessed by Doppler and catheter at three locations along the MV's intercommissural axis. When comparing dimensions of the rapid-prototyped valves to the subject echocardiography data sets, mean relative errors ranged from 6.2% to 35%. For the evaluated MVs, Doppler pressure gradients exhibited good agreement with catheter-measured gradients at a variety of flow rates, though with slight systematic overestimation in the recreated MAC valves. For all of the tested MVs, measuring the transmitral pressure gradient at differing valve orifice positions had minimal impact on observed gradients. Upon the testing of additional normal and calcific MVs, these data may contribute to an improved clinical understanding of MAC-related mitral stenosis. Moreover, they provide the ability to statistically evaluate between measurement locations, flow rates, and valve geometries for Doppler-derived pressure gradients. Determining these end points will contribute to greater clinical understanding for the diagnosis MAC patients and understanding the use and application of Doppler echocardiography to estimate transmitral pressure gradients.
Epitaxial growth and surface studies of the Half Heusler compound NiTiSn (001)
Authors: Kawasaki Jason K. , Neulinger Thomas , Timm Rainer , Hjort Martin , Zakharov Alexei A. , Mikkelsen Anders , Schultz Brian D. , Palmstrøm Chris J.
Published: May 2013

The Half Heuslers are currently an attractive family of compounds for high temperature thermoelectrics research, and recently, there has been renewed interest since some of these compounds are proposed to be topological insulators. NiTiSn belongs to the family of 18 valence electron Half Heuslers that are predicted to be semiconducting, despite being composed entirely of metallic elements. The growth of the Half Heusler compound NiTiSn by molecular beam epitaxy is demonstrated. The NiTiSn films are epitaxial and single crystalline as observed by reflection high-energy electron diffraction and x-ray diffraction. Temperature dependent transport measurements suggest the films may be semiconducting, but with a high background carrier density indicative of a high density of electrically active defect states. Methods of protecting the sample surface for synchrotron-based photoemission measurements are explored. These methods may be applied to the study of surface electronic structure in unconventional materials.
Combined in-situ photoemission spectroscopy and density functional theory of the Sr Zintl template for oxide heteroepitaxy on Si(001)
Authors: Seo Hosung , Choi Miri , Posadas Agham B. , Hatch Richard C. , Demkov Alexander A.
Published: May 2013

Half-monolayer Sr on Si(001) is a Zintl template necessary for epitaxial growth of SrTiO3 on Si(001). The authors investigate the reconstruction in the atomic and electronic structure of Si(001) induced by sub-monolayer Sr deposition using in-situ x-ray/ultraviolet photoemission spectroscopy and density functional theory. Sub-monolayer Sr is deposited on Si(001) using molecular beam epitaxy and the structural evolution of the surface is monitored using reflection high-energy electron diffraction. Experimentally, the authors find that the ionization energy of Si(001) decreases as a function of Sr coverage from 4.82 eV for pure Si(001) to 3.97 eV for half-monolayer Sr on Si(001) due to charge transfer from Sr to Si. They calculate the ionization energy for sub-monolayer Sr on Si(001) by considering several atomistic models and find good agreement with experiment. The authors clearly establish the Zintl character of the template by measuring the surface core level shifts of Si(001) and half-monolayer Sr/Si(001). They analyze and interpret the results of these measurements using first-principles final state theory.
Growth, doping, and characterization of ZnO nanowire arrays
Authors: Shen Gang , Dawahre Nabil , Waters Joseph , Kim Seongsin M. , Kung Patrick
Published: May 2013

Zinc oxide (ZnO) nanowire (NW) arrays were grown by chemical vapor deposition using the carbothermal reduction of ZnO powder at different pressures from 0.13 to 1.0 atm on basal plane sapphire substrates. The ZnO NWs were oriented in their [0001] direction. Lower growth pressures led to generally longer and smaller diameter wires. A model relating the length and diameter of the NWs was used to interpret the growth mechanism of these ZnO NWs as a function of pressure as the combination of adatom diffusion along the NW sidewalls and direct impingement growth on the NW tip. Al-doped ZnO NWs were synthesized by introducing Al power into the source material, resulting in an Al mole fraction up to 1.8 at. % in the NWs and a concurrent reduction in NW resistivity. Raman spectroscopy revealed slight lattice distortion to the ZnO crystal lattice, while room temperature photoluminescence showed an increase in the near band edge emission concurrently with a reduction in the green emission. The near band edge emission was also blue shifted in a manner consistent with the Burstein–Moss effect in degenerated semiconductor materials.
High-Strength Chemical-Vapor–Deposited Graphene and Grain Boundaries
Authors: Lee Gwan-Hyoung , Cooper Ryan C. , An Sung Joo , Lee Sunwoo , van der Zande Arend , Petrone Nicholas , Hammerberg Alexandra G. , Lee Changgu , Crawford Bryan , Oliver Warren , Kysar Jeffrey W. , Hone James
Published: May 2013

Graphene Staying Strong

Although exfoliated graphene can be extremely strong, it is produced on too small a scale for materials application. Graphene can be produced on a more practical scale by chemical vapor deposition, but the presence of grain boundaries between crystallites apparently weakens the material.

Lee
et al.

(p.
1073
) show that postprocessing steps during the removal of the graphene sheets can oxidize the grain boundaries and weaken them. If these steps are avoided, the material is comparable in strength to exfoliated graphene.
Vitamin Currency in a Lipid Exchange Market
Authors: Mesmin Bruno , Antonny Bruno
Published: May 2013

A lipid transfer protein moves vitamin E through the cell to the cell surface by exchanging it for a phosphoinositide in the plasma membrane.

[Also see Report by

Kono
et al.

]
Italian Parliament Orders €3 Million Trial of Disputed Therapy
Authors: Margottini Laura
Published: May 2013

A controversial stem cell treatment for neurodegenerative diseases, provided by the Stamina Foundation, is continuing on a small scale along with the trial.
Radiation Will Make Astronauts' Trip to Mars Even Riskier
Authors: Kerr Richard A.
Published: May 2013

Future astronauts headed for the Red Planet will have more than an imagined martian jinx to worry about: deep space radiation.
A Role for Science in Poverty Alleviation?
Authors: Bagla Pallava , Stone Richard
Published: May 2013

Science
spoke with Minister of Rural Development Jairam Ramesh about the role of science in poverty alleviation.
The Numbers Game
Authors: Hvistendahl Mara
Published: May 2013

In China, statistics have long been skewed by their use in rewarding performance; social scientists say they are beginning to remove those distortions.
Activity Increase in Respiratory Chain Complexes by Rubella Virus with Marginal Induction of Oxidative Stress
Authors: Claus C. , Schönefeld K. , Hübner D. , Chey S. , Reibetanz U. , Liebert U. G.
Published: May 2013

Mitochondria are important for the viral life cycle, mainly by providing the energy required for viral replication and assembly. A highly complex interaction with mitochondria is exerted by rubella virus (RV), which includes an increase in the mitochondrial membrane potential as a general marker for mitochondrial activity. We aimed in this study to provide a more comprehensive picture of the activity of mitochondrial respiratory chain complexes I to IV. Their activities were compared among three different cell lines. A strong and significant increase in the activity of mitochondrial respiratory enzyme succinate:ubiquinone oxidoreductase (complex II) and a moderate increase of ubiquinol:cytochromecoxidoreductase (complex III) were detected in all cell lines. In contrast, the activity of mitochondrial respiratory enzyme cytochromecoxidase (complex IV) was significantly decreased. The effects on mitochondrial functions appear to be RV specific, as they were absent in control infections with measles virus. Additionally, these alterations of the respiratory chain activity were not associated with an elevated transcription of oxidative stress proteins, and reactive oxygen species (ROS) were induced only marginally. Moreover, protein and/or mRNA levels of markers for mitochondrial biogenesis and structure were elevated, such as nuclear respiratory factors (NRFs) and mitofusin 2 (Mfn2). Together, these results establish a novel view on the regulation of mitochondrial functions by viruses.
Effect of argillic alteration on rock mass stability
Authors: Watters Robert J. , Delahaut Warren D.
Published: May 2013

The role of hydrothermal alteration in producing clay-rich rocks is discussed. Hydrothermal fluids derived from magmatic sources change rock lithologies to argillic rocks as a result of temperature, pressure and chemical effects. The grade of the argillization can vary from one in which only trace amounts of clay minerals are present to one in which there has been complete alteration into clay. Detailed geologic surface mapping and subsurface drilling are required to accurately delineate the extent and grade of alteration. Suggestions are presented for assessing the grade and amount of alteration. Two examples illustrate the effects of argillic alteration on the engineering design of excavated slopes. One example demonstrates a successful design where alteration effects were incorporated into the initial design stage. The second example illustrates where an inadequate geologic model underestimated the grade and extent of alteration, and a landslide of over four million tons of material resulted. Reappraisal of the geologic model enabled a successful mitigation and incorporation of the clay-rich lithologies to be designed, and permitted continued safe excavation at the site.
Groundwater flow and the stability of heterogeneous infinite slopes underlain by impervious substrata
Authors: Haneberg William C.
Published: May 2013

The effects of steady groundwater flow on the stability of heterogeneous infinite slopes underlain by impervious substrata were investigated using a series of computer simulations. A preliminary one-dimensional analysis shows that the magnitude of hydraulic head perturbation that can be attributed to flow across an idealized heterogeneity is controlled by both the size of the heterogeneity and the hydraulic conductivity contrast. In the limit, a perfectly impermeable heterogeneity will give rise to hydraulic gradients that are controlled by the normalized length of the heterogeneity, whereas an infinitely permeable heterogeneity will cause the hydraulic gradient to vanish across the heterogeneity. A series of two-dimensional finite-difference models shows that individual heterogeneities occupying 10% of the slope area can significantly perturb flow fields and influence local factors of safety in hypothetical slopes. Although local factors of safety are reduced enough to indicate the development of small secondary slides as a consequence of flow through or around heterogeneities, overall factors of safety remain unchanged. When heterogeneities are closely spaced, however, their effects on the stability of the model slopes are cumulative and in one case the overall factor of safety was increased by about 2%.
Playas and military operations
Authors: Neal James T.
Published: May 2013

Playas are among the most common of desert landforms, with more than 50,000 worldwide and with great variation in size and physical characteristics. They range from a hectare or less to hundreds of square kilometers, and they may support aircraft landings or be totally impassable to land vehicles. Because they possess distinctive physical attributes and are common elements of arid and semiarid landscapes, which occupy nearly 30% of the Earth's land surface, they have had significant effects on military history and operations for centuries. This significance is not apt to diminish.

The single most important determinant of playa-surface conditions is the combination of surface and ground-water hydrology. Playas with ground water that is sufficiently deep to preclude capillary rise favor hard surface crusts. Prolonged capillary or direct ground-water discharge in arid environments readily builds up evaporite mineral assemblages including halite, gypsum, and calcite. Changing hydrologic conditions resulting either naturally or from human activity, for example, ground-water extraction, can result in alteration of relief and surface hardness of playas over both short- and longer-time spans.

Military use by ground forces includes both expeditious and evasive maneuvering of ground vehicles. Air and spaceborne vehicles, including fixed and rotary wing craft and spacecraft, have used numerous playas in their natural state as landing platforms, and many other playas are readily available in remote, unpopulated areas of the globe. Future uses are apt to take advantage of the unique attributes of this arid-region feature—the flattest of all landforms.
Role of geology in assessing vulnerability of underground fortifications to conventional weapons attack
Authors: Eastler Thomas E. , Percious Donald J. , Fisher Paul R.
Published: May 2013

The military use of subsurface geologic environments dates back at least 5,000 years to Mesopotamia and Egypt, and continues to be a critical element in planning for both tactical and strategic military activities worldwide. In the context of present-day concerns of “proliferation,” the concept of geologic barriers and how best to defeat them has taken on new meaning. Characterization of the geology and the engineering properties of materials surrounding and constituting a deeply buried bedrock underground military facility (UGF) is of great military interest The degree of success of employing conventional munitions against such UGFs will be limited by our ability to understand the matter/energy interactions between penetrating conventional warheads and rock environments. Geotechnical information that can be used strategically to evaluate the vulnerability of UGFs is herein defined as “strategic geologic intelligence” and includes lithologic characterization; intact mechanical, weight/volume, penetrability; and interpreted in situ engineering properties of geologic units proximal to UGFs. Geologic vulnerability of UGFs can be considered primarily a function of three variables: depth, rock-mass strength, and surface-layer penetrability.

To the degree that any bedrock UGF is vulnerable to conventional weapons attack, the availability of appropriate site characterization data significantly increases one's ability to choose optimal weapons and tactics to defeat UGFs. Thus the role of “strategic geologic intelligence” in future war planning cannot be overstated.
Military Geology Unit of the U.S. Geological Survey during World War II
Authors: Terman Maurice J.
Published: May 2013

On June 24, 1942, the temporary Military Geology Unit of the U.S. Geological Survey was formalized after the U.S. Army Corps of Engineers requested them to prepare terrain intelligence studies to meet wartime priorities. The entire Military Geology Unit wartime roster was 114 professionals, including 88 geologists, 11 soil scientists, and 15 other specialists; 14 were women. Assisting staff (illustrators, typists, photographers, and others) totaled 43. The unit produced 313 studies, including 140 major terrain folios, 42 other major special reports, and 131 minor studies. These reports contain about 5,000 maps, 4,000 photographs and figures, 2,500 large tables, and 140 terrain diagrams. Most products were designed in the beginning for general strategic planning in Washington and later for detailed strategic planning overseas; they utilized graphics and nontechnical, telegraphic-style tabular texts.

The Military Geology Unit's principal effort was the preparation of the terrain folios titled Strategic Engineering Studies. They varied somewhat in content and format, but the key components usually were introduction, terrain appreciation, rivers, road and airfield construction, construction materials, and water resources. The folios, produced at an average rate of about one per week and at an average cost of $2,500, were compiled from scientific journals, books, maps, and photographs available in the Washington area by a team of 3 to 8 scientists; 8 to 12 teams might be working concurrently. MGU personnel took great pride in never having missed a delivery deadline.

In 1944, 5 Military Geology Unit consultants were sent to Europe and 5-man teams were assigned to the Southwest Pacific Area and to the Central Pacific Area. Each team produced large-scale terrain reports, mostly from aerial photographs, and consulted with engineer units and tactical officers in the field. By the end of the war, a consolidated 20-man team worked in Manila at the headquarters of the Armed Forces Pacific.
Clandestine Tunnel-4, northern Punchbowl, Korean Demilitarized Zone
Authors: Cameron C. P.
Published: May 2013

The Punchbowl is a large topographic basin in the rugged T'aebaek Mountains (T'aebaeksanmaek) of east-central Korea. Its steep northern rim is part of the Korean Demilitarized Zone (DMZ). This terrain was the target of various infiltration attempts in the postwar period and its potential to host clandestine tunnels was indicated by Allied intelligence studies of the early 1970s. In December 1989, at a depth of 145 m in intrusive granodiorite, a coherent cross-borehole electromagnetic anomaly with a signature indicative of an air-filled cavity was recorded by tunnel-search teams using continuous wave and pulsed ground-probing borehole-radar systems. Natural air-filled cavities at this depth were precluded by geological considerations and ground-water elevations. Target-evaluation drilling followed and, on December 24 at 0130 hours, a drill bit penetrated “Tunnel-4.” A borehole television camera provided clear images of artifacts of human tunnel-construction activity. Two and a half months later, Korean engineers, using a Wirth 3-m tunnel-boring machine (TBM), gained access to the tunnel and confirmed its nature and purpose.

Mapping and surveying of the tunnel revealed that (1) the tunnel was constructed by drill and blast methods in Mesozoic intrusive granodiorite, similar to that hosting previously identified DMZ Tunnel-2 and Tunnel-3, and in Precambrian gneiss; (2) the tunnel slopes up to the south at an average grade of 2.3%, ranging from a low of 0.91% to a high of 3.5%; (3) the average cross-sectional dimensions of the tunnel, 1.6 m × 1.6 m, are somewhat smaller than other hardrock tunnels discovered elsewhere in the DMZ; and (4) standard rock-mass rating schemes do not accurately predict tunnel-construction difficulty for hardrock tunnels smaller than 2 m × 2 m in cross section.
Fifty-four years of ephemeral channel response to two years of intense World War II military activity, Camp Iron Mountain, Mojave Desert, California
Authors: Nichols Kyle K. , Bierman Paul R.
Published: May 2013

During World War II, U.S. Army personnel lived, trained, and executed mock battles on low gradient piedmonts (~2°) in the Mojave Desert. For example, Camp Iron Mountain (established in 1942 by General George S. Patton, Jr., and used until 1944) housed up to 20000 Army personnel at any specific time. The camp is located on the large alluvial piedmont that extends from the Iron Mountains and is drained by shallow ephemeral channels.

At this camp, we made 18 detailed topographic maps in order to compare drainage networks of six undisturbed control plots and 12 plots disturbed by army activities. There are significant differences between the morphometery of small-scale, ephemeral drainage networks on control plots, on plots bisected by stone-walled walkways, and on plots down gradient of former army roads. Control plot channels are wider (2.05 ± 1.48 m) and deeper (8.8 ± 4.5 cm) than channels in walkway plots (width: 1.19 ± 0.71 m, depth: 7.4 ± 4.1 cm) and in road plots (width: 1.18 ± 0.61 m, depth: 7.2 ± 6.7 cm).

The military’s modification of the landscape affected subsequent channel originations and orientations. Channel heads were found in 76% of the compacted and smoothed walkways. In walkway plots, 80% of walkways caused the orientation of channels to deviate from the steepest piedmont gradient by more than 20°. After more than 50 years, road berms still act as local drainage divides. Down gradient of each intact road berm, there is a wide (20–40 m) zone in which no channels exist. Where channels have developed below intact road berms, they are smaller than channels in undisturbed control plots. Down gradient of breached road berms, wide, braided channels are common. Fifty-four years after camp abandonment, the channel network at Camp Iron Mountain has yet to recover, primarily because rock alignments and road berms continue to influence drainage patterns and local gradients.
Sustainability of military lands
Authors: Albertson Paul E.
Published: May 2013

Military land managers are faced with questions of landscape stability and sustainability. Fort Leonard Wood, Missouri, was selected to test these concerns because it has been the site of engineering training for over 50 years. Prior to U.S. Army occupancy, the landscape was undergoing disequilibrium resulting from historic land use activities. An integrated approach was used to examine landscape changes using existing information and technologies to answer geomorphic inquiries of equilibrium and recovery. The lack of a long-term sediment record was supplemented by performing soil-loss modeling. Soil simulations were done using the Revised Universal Soil Loss Equation (RUSLE) to simulate the effect of changing land use and land cover on soil loss. The aerial photographic record offered a means to create land cover for RUSLE simulations. The sustainable or acceptable soil-loss rate is known as the soil loss tolerance. Simulation of soil loss using 1938, 1955, 1976, and 1997 aerial photographs identified "hot spots" where soil loss was greater than tolerance. The results show that past Army training activities caused more soil loss than did presettlement activities, but that estimated soil loss from current training is less than loss rates before military occupancy of the landscape. Current best management practices are leading to landscape restoration within accepted soil loss tolerance. This study supports the U.S. Army’s commitment to landscape stewardship, which is essential for land-use sustainability.
Predicting fracture properties in weathered granite in denied areas
Authors: Ehlen Judy
Published: May 2013

This chapter describes a model developed to predict fracture properties of weathered granite in denied areas, predictions made using imagery, and a test undertaken to determine prediction accuracy. This project is part of a geotechnical characterization of weathered granites that will be used to predict weapons effects at denied sites. Joint spacings, orientations, and trace lengths were measured in four field areas near the denied sites. Three-dimensional models of field measurements from an analogue area and lineation data derived from imagery over this area and over two denied sites were sampled to determine mean joint spacings in simulated horizontal and vertical boreholes, mean joint trace length, joint intensity, termination percent, mean rock block width and volume, and RQD (Rock Quality Designation) at the denied sites. The simulated data were regressed against scale in log-log space and the equations for the best fit were used to calculate the predictions.

The predictions made for the denied sites are realistic compared to measurements made in the four field areas. They are within the standard deviations of field measurements and generally fall within the range of measurements made in the four field areas. Most predictions are within 25% of field measurements in the analogue area. The accuracy of the predictions was assessed by selecting one of the field areas as a denied area, and then using the same procedures to make predictions for the same set of variables. These predictions are very similar to the field measurements; most lie within 10–15%, indicating that predictions made using these procedures are accurate as well as realistic.
Geologic evaluation of a site for a nuclear power plant
Authors: Adair Merlyn J.
Published: May 2013

The scope and detail of geologic studies made for a nuclear power plant site far exceed those made for any other type of engineering structure. The regional and local physiography, geomorphology, geologic history, lithology, stratigraphy, and structural geology must be studied through (1) reviewing the literature, (2) discussions with local, academic, State and Federal geologists, geophysicists, and seismologists, and (3) original geologic mapping, geophysical studies, and subsurface investigations. Reviews of previous studies in the region are an important part of the evaluation of any site; they help to identify, and form the basis for, additional detailed studies of particular geologic conditions and features which may be significant to that site.

All historical earthquakes that could have been felt at a proposed site should be identified. All historical earthquakes of modified Mercalli (MM) intensity greater than IV or magnitude greater than 3 which have been reported within 200 mi (320 km) of a site are listed and shown on epicenter maps that also show significant tectonic structures within 200 mi of the site. The maximum potential earthquake for the site is evaluated from a consideration of the regional and local geologic setting and the historical seismicity. The maximum vibratory ground motion that safety-related plant structures and equipment are designed to withstand is defined on the basis of an evaluation of the maximum potential earthquake and the assumed location of the earthquake that will produce the maximum vibratory ground motion.

Geologic, seismic, and man-made hazards significant to the site are identified and evaluated. The soils and rock underlying a site are investigated to determine their characteristics and behavior under static and dynamic loads. Safety Analysis Reports (SARs) for the site are prepared. They document the studies which were made by the applicant; they also document that pertinent reports and studies by others were considered. The SARs provide the basis for the conclusions as to the geologic suitability of the site and the basis for the parameters selected for engineering design.
Geologic reports used in evaluation of nuclear reactor sites
Authors: Morris Robert H.
Published: May 2013

More than a decade has passed since the earliest geologic reports relating to proposed nuclear reactor sites were completed. Then, guidelines were few, and the safety analysis was brief and general. Today, the geologic portions of Preliminary Safety Analysis Reports (PSARs) and Final Safety Analysis Reports (FSARs) are by requirement more complex. Through the cooperative efforts of the Nuclear Regulatory Commission (NRC; formerly the Atomic Energy Commission) and the American Nuclear Society, specific seismic and geologic criteria for nuclear plant sites and a standard format for the presentation of data have been developed. These standards and requirements have shifted the emphasis of power plant siting from one that considered mainly the economics of the site and its proximity to the service area, as in the case of fossil fuel plants, to one that gives important consideration to the geologic suitability of the site.

Geologic studies of nuclear plant sites require a comprehensive exposition of the areal and structural geology, hydrology, and seismicity in addition to site exploration of engineering-geology and foundation characteristics, which are the major concerns in geologic studies for fossil fuel plants. For each site a design acceleration (g) value must be derived from studies of local and regional geology and seismicity. In recent years these studies have resulted in more comprehensive as well as more voluminous reports. Such an evolution has its problems. Reports commonly lack coherence and integration of subsurface and surface geology, particularly in the case of geophysical data. Cross reference is hampered when illustrations differ in scale. The geologic safety analysis should include more basic, original field investigations of the areal geology of the site and the surrounding area.
Mechanisms of surface subsidence resulting from solution extraction of salt
Authors: Ege John R.
Published: May 2013

Extraction of soluble minerals, whether by natural or man-induced processes, can result in localized land-surface subsidence. The subsidence is caused by partial or total collapse of underground cavities resulting from dissolution of salt or other soluble evaporites. In many cases, subsidence is ultimately related to the strength limit of the overlying rocks that form the unsupported roof above the cavity. Downwarping results where strength of roof spans are exceeded. In other cases, collapse of the undermined roof causes stoping of the overburden rocks. If sufficient underground space is available for the loosely packed rock debris to collect, the void can migrate to the surface and produce surface subsidence, or in the extreme, catastrophic surface collapse. Another mechanism is subsurface erosion of susceptible layers (sandstone, silt, loess) overlying salt cavities. Ground water can erode and transport the loose material down subsidence-induced and natural cracks, or drill holes into the salt cavity. The voids formed in the higher eroded beds can then cause surface subsidence.
Subsidence due to geothermal fluid withdrawal
Authors: Narasimhan T. N. , Goyal K. P.
Published: May 2013

Single-phase and two-phase geothermal reservoirs are currently being exploited for power production in Italy, Mexico, New Zealand, the United States, and elsewhere. Vertical ground displacements of up to 4.5 m and horizontal ground displacements of up to 0.5 m have been observed at Wairakei, New Zealand, that are clearly attributable to the resource exploitation. Similarly, vertical displacements of about 0.13 m have been recorded at The Geysers, California. No significant ground displacements that are attributable to large-scale fluid production have been observed at Larderello, Italy, and Cerro Prieto, Mexico. Observations show that subsidence due to geothermal fluid production is characterized by such features as an offset of the subsidence bowl from the main area of production, time-lag between production and subsidence, and nonlinear stress-strain relationships. Several plausible conceptual models, of varying degrees of sophistication, have been proposed to explain the observed features. At present, relatively more is known about the physical mechanisms that govern subsidence than the relevant thermal mechanisms. Although attempts have been made to simulate observed geothermal subsidence, the modeling efforts have been seriously limited by a lack of relevant field data needed to sufficiently characterize the complex field system.
Estimation of earthquake size for seismic hazards
Authors: dePolo Craig M. , Slemmons D. Burton
Published: May 2013

This chapter presents a structured organization of the various types of seismic-hazard estimates, approaches, scaling parameters, techniques, and data used in the estimation of potential earthquake sizes. This organization is designed to facilitate the use of multiple techniques, so that a greater amount of data can be incorporated into the size estimate. An earthquake size analysis begins with the determination of the type of seismic hazard to be estimated, such as characteristic, maximum, maximum credible, or floating earthquakes. The characteristic earthquake is defined as one that is characteristic of a particular fault or area. The maximum earthquake generally is defined as the largest to occur during a given time period, whereas the maximum credible earthquake is the largest that is reasonably physically possible, irrespective of the frequency of occurrence. Floating earthquakes occur along unidentified sources, e.g., along smaller faults adjacent to the major fault zones. The various types of estimates can be made at different levels of conservatism and probabilities of occurrence. Five approaches to earthquake size analysis are: historical earthquake, paleoseismic, source characterization, regional, and relative comparison approaches. For each of these, various parameters are used to scale earthquake size, including fault rupture length, fault rupture area, fault displacement, seismic moment calculations, and strain rates. Techniques include the specific correlations and equations used in the analysis. Data include the information collected and its associated uncertainties. The combined use of several approaches, scaling parameters, techniques, and data may reduce the overall uncertainty (or increase the confidence) in the analysis. Logic trees offer a useful format for presenting multiple estimates and uncertainties in an explicit manner. It is important to understand the type of earthquake size estimate made (e.g., local magnitude, surface-wave magnitude, or seismic moment), and to be internally consistent about the type used throughout the analysis, most importantly in the techniques and data. Current research in seismic-hazard analysis includes studies in intraplate regions (e.g., central and eastern United States) and on fold-related, subduction-zone, and volcanic earthquake sources.
Implications of the Meers fault on seismic potential in the central United States
Authors: Ramelli Alan R. , Slemmons D. Burton
Published: May 2013

The Meers fault in southwestern Oklahoma, with a prominent scarp resulting from late Holocene surface displacement, is the best-expressed late Quaternary surface fault known to occur in a “stable” continental interior (or mid-plate) region (i.e., regions far removed from areas of high tectonic rates). The Meers fault is part of a major fault system that has not been the locus of major tectonic activity since the Paleozoic, and although recent surface displacements have been sizable, average late Quaternary rates have been low, based on a lack of geomorphic expression indicating significant cumulative displacement. Activity of the Meers fault is unusual, because in mid-plate regions, few large historical earthquakes have occurred and recognized cases of late Quaternary surface faulting are very rare.

Based on the extent of surface rupturing and amounts of displacement, the Meers fault appears capable of producing very large events (i.e., M > 7, or possibly even M > 7 ½). Recent events on the Meers fault produced surface displacements of a few to several meters. Such displacements are quite large, relative to the rupture length of about 40 km, and could result from a tendency for mid-plate or long-recurrence faults to rupture with higher stress drops than plate-margin or short-recurrence faults. Studies attempting to evaluate this possibility have produced conflicting results and may indicate this cannot be placed in as simple a context as plate-margin versus intraplate settings. A large earthquake on the Meers fault would produce strong ground motion throughout much of the south-central United States and could cause widespread damage. The existence of a potential source of large earthquakes in a region thought to be tectonically stable suggests that the seismic potential of this and other mid-plate regions may be underestimated.
Surficial slope failures in southern California hillside residential areas
Authors: Merifield P. M.
Published: May 2013

Widespread damage in hillside areas of southern California resulting from major rainstorms during 1978 and 1980 focused attention on risks to life and property from surficial slope failures, including debris slides, debris flows, and debris floods. Both artificial and natural slopes underwent damaging surficial failures; however, mountain and foothill areas below burned watersheds were affected by considerably more debris than unburned areas. Slopes vegetated with grasses or other ground cover lacking deep root systems were particularly susceptible to failure.

Preventive measures include stricter enforcement of existing grading codes (includ-ing the requirement for a continuous cover of deep-rooted vegetation), stability analyses of surficial failures, regional studies by state and local governments to identify hazardous areas, site-specific investigations by consultants when properties change hands, and increased efforts to educate the public about slope maintenance in order to mitigate slope failures.
Recent developments in landslide mitigation techniques
Authors: Rogers J. David
Published: May 2013

This chapter begins with a brief synopsis of landslide repair methodologies developed over the past 70 years. Early attempts at stabilizing slopes focused on em-placement of toe buttresses and inclusion of subdrainage. As earthwork equipment became larger and more capable, the removal and recompaction of entire slide masses became commonplace. Over the past decade, geotextile and geomembrane products have become available that can significantly alter the options for repair, especially under conditions of restricted access or poor weather. In the balance of the chapter, I seek to introduce the reader to some of these products and to case histories of ways in which they have been combined to effect novel solutions to slope stability problems.