Studies of Ground Conductivity in the Territory of Alaska

The effective ground conductivity of Alaska has been determined by a comparison of experimental and theoretical field strengths. The experimental field strengths have been obtained by use of an airborne receiver, flown along radial paths from a large number of CAA radio ranges and beacons. The surface wave attenuation factor was computed for both a plane and a curved, homogeneous earth by methods presented by Norton. The experimentally determined relative field strengths were plotted as a function of distance and were compared with a family of curves for assumed values of conductivity and dielectric constant. From this comparison, that value of conductivity that best fits the experimental data is taken as the effective conductivity over the path. An investigation of the effect at dielectric constant on the transmitted signal shows that, within the frequency range used, a change of dielectric constant from 1 to 20 has but little effect on the attenuation of the transmitted signal for values of conductivity between 1 and 5 mmho/m. The experimental results indicate that for most sections of Alaska, the effective conductivity falls within this range. In some cases the earth was not homogeneous over the entire flight path as evidenced by changes in the slope of the field strength vs distance curves. In such cases, the data were replotted with an initial point at the discontinuity and new theoretical curves were drawn for each section of the field strength vs distance curves. Investigation of the variation of effective conductivity with change of frequency and at different seasons was made. In addition, wave tilt methods of determining the conductivity were used. A 'Ground Constants Measuring Set' was obtained from the Signal Corps and measurements were made in selected areas in Alaska. Attempts were made to use 1height-gain' and 'mutual coupling of loops' techniques but these were not successful. An investigation of anomolous propagation in the vicinity of Point Barrow was made. It was determined that this anomolous propagation appears to be the result of a layered earth. In addition to the anomolous propagation in the vicinity of Point Barrow, there appears to be similar anomolies in the vicinity of Kotzebue, Galena, Bethel and Port Heiden. From the above investigations a map showing the effective conductivity of Alaska as determined by the attenuation method is presented.Navy Department Bureau of Ships NObsr 72528 NE 120308 Subtask No. 6ABSTRACT -- PART I A. Purpose -- B. General Factual Data -- C. Detail Factual Data -- PART II -- A, Conclusions -- APPENDIX IYe

Method for analyzing radiation sensitivity of integrated circuits

A method for analyzing the radiation sensitivity of an integrated circuit is described to determine the components. The application of a narrow radiation beam to portions of the circuit is considered. The circuit is operated under normal bias conditions during the application of radiation in a dosage that is likely to cause malfunction of at least some transistors, while the circuit is monitored for failure of the irradiated transistor. When a radiation sensitive transistor is found, then the radiation beam is further narrowed and, using a fresh integrated circuit, a very narrow beam is applied to different parts of the transistor, such as its junctions, to locate the points of greatest sensitivity

A Consistent Histogram Estimator for Exchangeable Graph Models

Exchangeable graph models (ExGM) subsume a number of popular network models. The mathematical object that characterizes an ExGM is termed a graphon. Finding scalable estimators of graphons, provably consistent, remains an open issue. In this paper, we propose a histogram estimator of a graphon that is provably consistent and numerically efficient. The proposed estimator is based on a sorting-and-smoothing (SAS) algorithm, which first sorts the empirical degree of a graph, then smooths the sorted graph using total variation minimization. The consistency of the SAS algorithm is proved by leveraging sparsity concepts from compressed sensing.Comment: 28 pages, 5 figure

The propagator for the step potential using the path decomposition expansion

We present a direct path integral derivation of the propagator in the presence of a step potential. The derivation makes use of the Path Decomposition Expansion (PDX), and also of the definition of the propagator as a limit of lattice paths.Comment: To appear in DICE 2008 conference proceeding

SNACK PEANUTS PURCHASE PATTERN: EFFECTS OF NUTRITIONAL CONSIDERATIONS AND HOUSEHOLD CHARACTERISTICS

This study examines the effect of a meal planner's nutritional awareness, exercise habits, and household socioeconomic characteristics on market participation and frequency of purchase of snack peanuts. Data are from a household survey of 2880 U.S. households collected by Gallup in 1997. Statistical tests showed that a double-hurdle or Cragg model best represented consumers' participation and purchase level decisions in the snack peanut market. The results indicated that meal planner's nutritional considerations while making food purchase decisions had little effect on the participation level decisions, but did affect purchase frequency of snack peanuts. Those household meal planners who were overly concerned about undesirable nutritional factors tended to decrease their purchase of snack peanuts. Promotion of snack peanuts on the basis of nutritional benefits through health professional and media is a useful tool to increase purchase frequency.Food Consumption/Nutrition/Food Safety,

Import Demand for Shelled Peanuts in the European Union: Impacts of the U.S. Export Promotion Program

The objective of this study is to propose a system of input demand functions consistent with the theory of the firm where promotion is treated as an information input in the production function. The empirical model is applied to the European Union (EU) input demand for shelled peanuts. The information input is measured as Euros spent on the U.S. Foreign Market Development program (FMD) on peanuts by the U.S. in the EU market. We find that the FMD program had a positive effect on the EU demand for U.S. shelled peanuts. This result suggests that the information provided to manufactures through the FMD has helped to increase the demand for shelled U.S. peanuts in the EU markets. The estimated marginal return of U.S. export promotion expenditures on the FMD program is 240 Euros.Input demand, Shelled peanuts, U.S. Foreign Market Development Program, International Relations/Trade,

Equation of State of Supercooled Water from the Sedimentation Profile

To study the coexistence of two liquid states of water within one simulation box, we implement an equilibrium sedimentation method--which involves applying a gravitational field to the system and measuring/calculating the resulting density profile in equilibrium. We simulate a system of particles interacting via the ST2 potential, a model for water. We detect the coexistence of two liquid phases at low temperature.Comment: 4 pages, 4 EPS figure

Household Snack-Food Purchases: Does Nutrition Matter?

Purchase patterns for two types of snack foods--pretzels and popcorn, and potato, corn, and tortilla chips--were analyzed using the data from a national survey. The study examined the effect of socio-economic and lifestyle factors including nutritional awareness and exercise habits of household respondents on snack-food purchase. A geometric-hurdle count-data model that distinguished between market-participation and purchase-frequency decisions revealed that the decision to participate in the market for snack food was separate from the purchase-level decision. Pretzels and popcorn consumers were unaffected by nutrition consideration of any kind. However, respondents who were overly concerned about desirable nutritional factors were unlikely to be buyers or potential buyers of snacks such as potato, corn, and tortilla chips.Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

Evidence of improved inventory control

Inventory data applied to a standard partial stock-adjustment model demonstrate that inventory control, defined by desired marginal inventory-sales ratios and speeds of adjustment, improved in the last decade or so, particularly in the manufacturing sector. In addition, the evidence suggests that, contrary to popular wisdom, the net effect of these changes in inventory control has been to increase the volatility of inventory investment in both the manufacturing and trade sectors.Inventories

Returns, Lags, and Complementarities in Brand and Generic Advertising: The Demand for Peanut Butter

This paper estimates the impact of generic and brand advertising on the demand for peanut butter in the U.S. An error correction model is estimated with quarterly data from 1985 to 2004 to study both the short- and long-run adjustments. The results indicate that brand advertising has a significant but short-lived effect on aggregate consumption while generic advertising has little short-run but significant long-run effects.Demand and Price Analysis, Marketing,