Unsteady flow in a storm drainage system

CER69-70AB1.June 1969.Includes bibliographical references.U.S. Bureau of Public Roads Contract No. CPR-11-3584.Under contract no. CPR-11-3584

Report on photogrammetric determination of relative snow area

CER69-70AHB-40.June 1970.For U.S. Forest Service Rocky Mountain Forest and Range Experiment Station

Determination of snow depth and water equivalent by remote sensing

Submitted to Office of Water Research and Technology, U.S. Department of the Interior.June 1976.This exploratory study was designed to investigate the possibilities of using inexpensive aerial remote sensing methods to measure the snowpack and its water content. The relation of snow depth and elevation on the same aspect (north or south) was definitely linear but the slopes of the regression lines varied between months and between years. Thus no uniform prediction was possible of snow depth over an entire watershed from a single measurement at one point. Example: The regression equation for March 4, 1972 on the north aspect was YSNOW DEPTH(dm)= -24.5 + (1.10 ± 0.51)XELEV(100m). Snow depth and water equivalent were consistently related to melt date, sometimes quite strongly. The addition of vegetation density to the equation significantly increased the proportion of variability of snow depth which is accounted for. Little strength was added by including the other environmental factors, - aspect, elevation, and slope degree. However, elevation was more strongly related to snow depth early in the spring and aspect was more strongly related later. Prediction of water equivalent was improved by including degree of slope early in the season, and by including aspect and then slope later in the season. An example of multiple regression equation with a multiple R of 0.81 is YSNMAR= -14.0 + 0.08XMELTDA+ 0.095XVEGDEN+ 0.004XELEV - 0.021XFROMN- 0.053XSLOPE where subscripts mean SNow depth (dm) in MARch, MELT DAte (year-day), VEGetation DENsity (100-foot candles), ELEVation (meters), azimuth FROM due North less than 180° (degrees), and degree of SLOPE (Percent). Therefore by measuring the melt date and environmental variables one could predict snow depth and water equivalent, once these equations were established for a given area. Melt date can be measured by observation from two aerial flights at three-day intervals in early spring. The relationship between the elevation of the snow-melt line and time was determined to be linear for each of the three years observed. The average slope of the linear regression was 19.64 meters per day (0.82 meters per hour) during the snow melt period. This rate of recedence was consistent during the three-year period of observation. The variation in date over the three-year period for the snow-melt line to be at a given elevation, was approximately equivalent to the time period for the snow-melt line to raise 600 meters. The photogrammetric determination of snow depths over the area was restricted by the limited number of ground control targets. The measurement and computational procedures for the photographic imagery were adequate for the intended purpose. The determination of the location of additional visible ground control in the available photography would permit more definitive results. The point measurement of the elevation of snow fields can be accomplished if there are sufficient shadows due to vegetation or image texture due to dirt or surface irregularities. Our conclusion is that determination of snow depth and water equivalent by remote sensing from aircraft is possible. We have uncovered the basic principles but further work is needed to develop the method.OWRT Project no. A-019-COLO; supported (in part) by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized by the Water Resources Research Act of 1964, and pursuant to Grant Agreement Nos. 14-31-0001-3806, 14-13-0001-4006, and 14-31-0001-5006

Solution of problems of unsteady free surface flow in storm drains

November 1970.Includes bibliographical references (pages 74-79)

Evaluation of geometric and hydraulic parameters

November 1970.Includes bibliographical references (page 37)

Large-scale structure of a nation-wide production network

Production in an economy is a set of firms' activities as suppliers and customers; a firm buys goods from other firms, puts value added and sells products to others in a giant network of production. Empirical study is lacking despite the fact that the structure of the production network is important to understand and make models for many aspects of dynamics in economy. We study a nation-wide production network comprising a million firms and millions of supplier-customer links by using recent statistical methods developed in physics. We show in the empirical analysis scale-free degree distribution, disassortativity, correlation of degree to firm-size, and community structure having sectoral and regional modules. Since suppliers usually provide credit to their customers, who supply it to theirs in turn, each link is actually a creditor-debtor relationship. We also study chains of failures or bankruptcies that take place along those links in the network, and corresponding avalanche-size distribution.Comment: 17 pages with 8 figures; revised section VI and references adde

HDAC9 is implicated in atherosclerotic aortic calcification and affects vascular smooth muscle cell phenotype.

Aortic calcification is an important independent predictor of future cardiovascular events. We performed a genome-wide association meta-analysis to determine SNPs associated with the extent of abdominal aortic calcification (n = 9,417) or descending thoracic aortic calcification (n = 8,422). Two genetic loci, HDAC9 and RAP1GAP, were associated with abdominal aortic calcification at a genome-wide level (P < 5.0 × 10-8). No SNPs were associated with thoracic aortic calcification at the genome-wide threshold. Increased expression of HDAC9 in human aortic smooth muscle cells promoted calcification and reduced contractility, while inhibition of HDAC9 in human aortic smooth muscle cells inhibited calcification and enhanced cell contractility. In matrix Gla protein-deficient mice, a model of human vascular calcification, mice lacking HDAC9 had a 40% reduction in aortic calcification and improved survival. This translational genomic study identifies the first genetic risk locus associated with calcification of the abdominal aorta and describes a previously unknown role for HDAC9 in the development of vascular calcification

Zettawatt-Exawatt Lasers and Their Applications in Ultrastrong-Field Physics: High Energy Front

Since its birth, the laser has been extraordinarily effective in the study and applications of laser-matter interaction at the atomic and molecular level and in the nonlinear optics of the bound electron. In its early life, the laser was associated with the physics of electron volts and of the chemical bond. Over the past fifteen years, however, we have seen a surge in our ability to produce high intensities, five to six orders of magnitude higher than was possible before. At these intensities, particles, electrons and protons, acquire kinetic energy in the mega-electron-volt range through interaction with intense laser fields. This opens a new age for the laser, the age of nonlinear relativistic optics coupling even with nuclear physics. We suggest a path to reach an extremely high-intensity level $10^{26-28}$W/cm$^2$ in the coming decade, much beyond the current and near future intensity regime $10^{23}$W/cm$^2$, taking advantage of the megajoule laser facilities. Such a laser at extreme high intensity could accelerate particles to frontiers of high energy, tera-electron-volt and peta-electron-volt, and would become a tool of fundamental physics encompassing particle physics, gravitational physics, nonlinear field theory, ultrahigh-pressure physics, astrophysics, and cosmology. We focus our attention on high-energy applications in particular and the possibility of merged reinforcement of high-energy physics and ultraintense laser.Comment: 25 pages. 1 figur

Towards an Intelligent Tutor for Mathematical Proofs

Computer-supported learning is an increasingly important form of study since it allows for independent learning and individualized instruction. In this paper, we discuss a novel approach to developing an intelligent tutoring system for teaching textbook-style mathematical proofs. We characterize the particularities of the domain and discuss common ITS design models. Our approach is motivated by phenomena found in a corpus of tutorial dialogs that were collected in a Wizard-of-Oz experiment. We show how an intelligent tutor for textbook-style mathematical proofs can be built on top of an adapted assertion-level proof assistant by reusing representations and proof search strategies originally developed for automated and interactive theorem proving. The resulting prototype was successfully evaluated on a corpus of tutorial dialogs and yields good results.Comment: In Proceedings THedu'11, arXiv:1202.453

Large-scale genome-wide association studies and meta-analyses of longitudinal change in adult lung function.

BACKGROUND: Genome-wide association studies (GWAS) have identified numerous loci influencing cross-sectional lung function, but less is known about genes influencing longitudinal change in lung function. METHODS: We performed GWAS of the rate of change in forced expiratory volume in the first second (FEV1) in 14 longitudinal, population-based cohort studies comprising 27,249 adults of European ancestry using linear mixed effects model and combined cohort-specific results using fixed effect meta-analysis to identify novel genetic loci associated with longitudinal change in lung function. Gene expression analyses were subsequently performed for identified genetic loci. As a secondary aim, we estimated the mean rate of decline in FEV1 by smoking pattern, irrespective of genotypes, across these 14 studies using meta-analysis. RESULTS: The overall meta-analysis produced suggestive evidence for association at the novel IL16/STARD5/TMC3 locus on chromosome 15 (P  =  5.71 × 10(-7)). In addition, meta-analysis using the five cohorts with ≥3 FEV1 measurements per participant identified the novel ME3 locus on chromosome 11 (P  =  2.18 × 10(-8)) at genome-wide significance. Neither locus was associated with FEV1 decline in two additional cohort studies. We confirmed gene expression of IL16, STARD5, and ME3 in multiple lung tissues. Publicly available microarray data confirmed differential expression of all three genes in lung samples from COPD patients compared with controls. Irrespective of genotypes, the combined estimate for FEV1 decline was 26.9, 29.2 and 35.7 mL/year in never, former, and persistent smokers, respectively. CONCLUSIONS: In this large-scale GWAS, we identified two novel genetic loci in association with the rate of change in FEV1 that harbor candidate genes with biologically plausible functional links to lung function