Improving Performance of M-to-N Processing and Data Redistribution in In Transit Analysis and Visualization

In an in transit setting, a parallel data producer, such as a numerical simulation, runs on one set of ranks M, while a data consumer, such as a parallel visualization application, runs on a different set of ranks N. One of the central challenges in this in transit setting is to determine the mapping of data from the set of M producer ranks to the set of N consumer ranks. This is a challenging problem for several reasons, such as the producer and consumer codes potentially having different scaling characteristics and different data models. The resulting mapping from M to N ranks can have a significant impact on aggregate application performance. In this work, we present an approach for performing this M-to-N mapping in a way that has broad applicability across a diversity of data producer and consumer applications. We evaluate its design and performance with a study that runs at high concurrency on a modern HPC platform. By leveraging design characteristics, which facilitate an “intelligent” mapping from M-to-N, we observe significant performance gains are possible in terms of several different metrics, including time-to-solution and amount of data moved

Feasibility of a New Indiana Coordinate Reference System (INCRS)

Engineers, Surveyors, and GIS Professionals spend an enormous amount of time correcting field surveys to the classical State Plane Coordinate System (SPCS). The current mapping corrections are in the order of 1:33,000, or 30 parts per million (ppm). Modern surveys (e.g., GPS/InCORS) have an accuracy of a few parts per million. Whenever original surveys made on the surface of the Earth need to be reduced to a mapping reference surface, surveyed distances and angles (azimuths) need to be corrected. Measured distances need to be corrected for two scale factors: 1) due to the mapping scale inherent in conformal mappings, and 2) due to terrain heights. Measured angles (azimuths) need to be corrected for so-called convergence angles. The application of these necessary corrections is time consuming and may add an estimated 15 to 20% to the cost of a survey. The omission of these corrections corrupts the reliability of survey results. A new Indiana Coordinate Reference System (INCRS) allows for so much smaller corrections that when omitted the errors committed are small, and may be even neglected for surveys less accurate than a few ppm. In a few areas of Indiana (e.g. Clark County), terrain heights corrections are still needed because these corrections due to the terrain roughness are at the 14 ppm level. Not only reduces the proposed INCRS reduces the scale factor from 30 ppm to a few ppm, but also the convergence angles are reduced by a factor of four (from about 0.5 degree to about 7-8 arcminutes)

Laser Mobile Mapping Standards and Applications in Transportation

This report describes the work that was done to support the development of a chapter for the INDOT Survey Manual on Mobile Mapping. The work includes experiments that were done, data that was collected, analysis that was carried out, and conclusions that were drawn about accuracy of Mobile Terrestrial Laser Scanning (MTLS) systems. The resulting Manual chapter, located in the appendix, defines standards and procedures for preparing, collecting, editing, delivering, exploiting, and archiving electronic mapping data that is created for Indiana Department of Transportation (INDOT). The purpose of the standards and procedures within this manual is to obtain statewide uniformity within the INDOT combined Aerial/Ground Survey process, to establish and maintain MTLS Standards for INDOT and contracted consultants, and allow for all of the project data to be effectively managed from conception to completion. These standards apply to all projects delivered to INDOT by contracted consulting firms, or exchanged internally within INDOT or between state agencies. The standards and procedures are the result of mobile terrestrial laser scanning surveys of two test sites - one urban and one freeway - created for this project. After establishing reference control points on the sites, each site was surveyed by four mobile terrestrial laser scanning vendors. The results from the vendor data over the test sites, in addition to information in published literature, are the basis for the specifications manual. The proposed chapter for the Survey Manual is in Appendix E of this report

Principles and evaluation of autostereoscopic photogrammetric measurement

Stereoscopic perception is a basic requirement for photogrammetric 3D measurement and accurate geospatial data collection. Ordinary stereoscopic techniques require operators wearing glasses or using eyepieces for interpretation and measurement. However, the recent emerging autostereoscopic technology makes it possible to eliminate this requirement. This paper studies the principles and implementation of autostereoscopic photogrammetric measurement and evaluates its performance. We first describe the principles and properties of the parallax barrier-based autostereoscopic display used in this study. As an important metric property, we quantitatively present the autostereoscopic geometry, including viewing zones and the boundary of a viewer\u27s movement for autostereoscopic measurement. A toolkit AUTO3D is developed that has common photogrammetric functions. The implementation principles are described by addressing the differences compared to the ordinary stereoscopic technology. To evaluate the performance of the autostereoscopic measurement, images at a resolution of 25 μm and 50 μm are measured by a group of seven (7) operators, who are asked to digitize 18 well-defined roof points and 18 ground points. These results are evaluated by comparing the same measurements obtained from a popular stereoscopic photogrammetric workstation. It is shown that the precision of autostereoscopic measurement is about 16 percent to 25 percent lower than the conventional stereo workstation. © 2006 American Society for Photogrammetry and Remote Sensing

A STUDY ON SENSOR MODELING AND TRIANGULATION FOR AN AIRBORNE THREE LINE SCANNER

ABSTRACT From the end of the twentieth century, commercial vendors have introduced airborne three line scanners, instead of more traditional single line scanners. While ADS40 (Leica Geosystems) and TLS (STARLABO) placed CCD arrays on the focal plane in a single optical system, 3-DAS-1 and 3-OC (Wehrli & Associates) use three optical systems but rigidly fixed to each other. For this reason, we need to develop a photogrammetric model for three different cameras but moving together along a single flight trajectory. In this paper, we present a sensor model for such a three line scanner and a piece-wise polynomial trajectory model. Preliminary triangulation results show that when geometric constraints on the trajectory model are loosely weighted, the misclosures in the image space are around 3 pixels while misclosures were increased up to 9 pixels if the geometric constraints are strictly enforced

Commute Times, Food Retail Gaps, and Body Mass Index in North Carolina Counties

Introduction: The prevalence of obesity is higher in rural than in urban areas of the United States, for reasons that are not well understood. We examined correlations between percentage of rural residents, commute times, food retail gap per capita, and body mass index (BMI) among North Carolina residents. Methods: We used 2000 census data to determine each county\u27s percentage of rural residents and 1990 and 2000 census data to obtain mean county-level commute times. We obtained county-level food retail gap per capita, defined as the difference between county-level food demand and county-level food sales in 2008, from the North Carolina Department of Commerce, and BMI data from the 2007 North Carolina Behavioral Risk Factor Surveillance System. To examine county-level associations between BMI and percentage of rural residents, commute times, and food retail gap per capita, we used Pearson correlation coefficients. To examine cross-sectional associations between individual-level BMI (n=9,375) and county-level commute times and food retail gap per capita, we used multilevel regression models. Results: The percentage of rural residents was positively correlated with commute times, food retail gaps, and county-level BMI. Individual-level BMI was positively associated with county-level commute times and food retail gaps. Conclusions: Longer commute times and greater retail gaps may contribute to the rural obesity disparity. Future research should examine these relationships longitudinally and should test community-level obesity prevention

LEADER-4

Objective: As glucagon-like peptide-1 receptor agonists lower blood pressure (BP) in type 2 diabetes mellitus (T2DM), we examined BP control in relation to targets set by international bodies prior to randomization in the Liraglutide Effect and Action in Diabetes: Evaluation of cardiovascular outcome Results (LEADER) trial. Methods: We analyzed baseline data from LEADER (NCT01179048), an ongoing phase 3B, randomized, double-blind, placebo-controlled cardiovascular outcomes trial examining the cardiovascular safety of the glucagon-like peptide-1 receptor agonist liraglutide in 9340 people with T2DM from 32 countries [age (all mean +/- SD) 64 +/- 7.2 years, BMI 32.5 +/- 6.3 kg/m2, duration of diabetes 12.7 +/- 8.0 years], all of whom were at high risk for cardiovascular disease (CVD). Results: A total of 81% (n = 7592) of participants had prior CVD and 90% (n = 8408) had a prior history of hypertension. Despite prescription of multiple antihypertensive agents at baseline, only 51% were treated to a target BP of less than 140/85 mmHg and only 26% to the recommended baseline BP target of less than 130/80 mmHg. In univariate analyses, those with prior CVD were prescribed more agents (P < 0.001) and had lower BP than those without (137 +/- 18.8/78 +/- 10.6 mmHg versus 140 +/- 17.7/80 +/- 9.9 mmHg; P < 0.001). In logistic regression analyses, residency in North America (64% treated to <140/85 mmHg; 38% treated to <130/80 mmHg) was the strongest predictor of BP control. Conclusion: These contemporary data confirm that BP remains insufficiently controlled in a large proportion of individuals with T2DM at high cardiovascular risk, particularly outside North America. Longitudinal data from the LEADER trial may provide further insights into BP control in relation to cardiovascular outcomes in this condition