The OCBI Tipping Point, August 29, 2007, Vol. 1, no.4

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

The OCBI Tipping Point, December 7, 2007, Vol. 1, no.5

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

Audit report on the City of Center Point, Iowa for the year ended June 30, 2009

Audit report on the City of Center Point, Iowa for the year ended June 30, 2009

Audit report on the City of Center Point, Iowa for the year ended June 30, 2010

Audit report on the City of Center Point, Iowa for the year ended June 30, 2010

Audit report on the City of Center Point, Iowa for the year ended June 30, 2011

Audit report on the City of Center Point, Iowa for the year ended June 30, 2011

Single Point of Entry Long-Term Living Resource System Team Report

Pursuant to House File 451 the Single Point of Entry Long-Term Living Resources System Team, involving several state agencies as well as interested associations, submitted a report to the legislature on recommendations to establish a single point of entry system.

Audit report on the City of Center Point, Iowa for the year ended June 30, 2012

Audit report on the City of Center Point, Iowa for the year ended June 30, 2012

Production of Acetic Acid by Fermentation with Propionibacteria, HR-321, 1993

This project was undertaken jointly with a project supported by the Iowa Corn Promotion Board. Together the projects aimed at producing the organic acids, propionic acid and acetic acid, by fermentation. The impacts were to provide agriculturally-based alternatives to production of these acids, currently produced mainly as petrochemicals. The potentially high-demand use for acetic acid is as the "acetate" in Calcium Magnesium Acetate (CMA), the non-corrosive road deicer. Fermentation was, however, far from being an economically acceptable alternative. Gains were made in this work toward making this a feasible route. These advances included (1) development of a variant strain of propionibacteria capable of producing higher concentrations of acids; (2) comparison of conditions for several ways of cultivating free cells and establishment of the relative benefits of each; (3) achievement of the highest productivity in fermentations using immobilized cells; (4) identification of corn steep liquor as a lower cost substrate for the fermentation; (5) application of a membrane extraction system for acid recovery and reduction of product inhibition; and (6) initial use of more detailed economic analysis of process alternatives to guide in the identification of where the greatest payback potential is for future research. At this point, the fermentation route to these acids using the propionibacteria is technically feasible, but economically unfeasible. Future work with integration of the above process improvements can be expected to lead to further gains in economics. However, such work can not be expected to make CMA a less expensive deicer than common road salt.

Using Scanning Lasers for Real-Time Pavement Thickness Measurement, TR-538, 2006

Due to limited budgets and reduced inspection staff, state departments of transportation (DOTs) are in need of innovative approaches for providing more efficient quality assurance on concrete paving projects. The goal of this research was to investigate and test new methods that can determine pavement thickness in real time. Three methods were evaluated: laser scanning, ultrasonic sensors, and eddy current sensors. Laser scanning, which scans the surface of the base prior to paving and then scans the surface after paving, can determine the thickness at any point. Also, scanning lasers provide thorough data coverage that can be used to calculate thickness variance accurately and identify any areas where the thickness is below tolerance. Ultrasonic and eddy current sensors also have the potential to measure thickness nondestructively at discrete points and may result in an easier method of obtaining thickness. There appear to be two viable approaches for measuring concrete pavement thickness during the paving operation: laser scanning and eddy current sensors. Laser scanning has proved to be a reliable technique in terms of its ability to provide virtual core thickness with low variability. Research is still required to develop a prototype system that integrates point cloud data from two scanners. Eddy current sensors have also proved to be a suitable alternative, and are probably closer to field implementation than the laser scanning approach. As a next step for this research project, it is suggested that a pavement thickness measuring device using eddy current sensors be created, which would involve both a handheld and paver-mounted version of the device.

Audit report on the City of Center Point, Iowa for the year ended June 30, 2013

Audit report on the City of Center Point, Iowa for the year ended June 30, 2013

Effectiveness of Electrochemical Chloride Extraction for the Iowa Avenue Pedestrian Bridge, TR-499, 2005

The main objective of this study is to determine the effectiveness of the Electrochemical Chloride Extraction (ECE) technique on a bridge deck with very high concentrations of chloride. This ECE technique was used during the summer of 2003 to reverse the effects of corrosion, which had occurred in the reinforcing steel embedded in the pedestrian bridge deck over Highway 6, along Iowa Avenue, in Iowa City, Iowa, USA. First, the half cell potential was measured to determine the existing corrosion level in the field. The half-cell potential values were in the indecisive range of corrosion (between -200 mV and -350 mV). The ECE technique was then applied to remove the chloride from the bridge deck. The chloride content in the deck was significantly reduced from 25 lb/cy to 4.96 lb/cy in 8 weeks. Concrete cores obtained from the deck were measured for their compressive strengths and there was no reduction in strength due to the ECE technique. Laboratory tests were also performed to demonstrate the effectiveness of the ECE process. In order to simulate the corrosion in the bridge deck, two reinforced slabs and 12 reinforced beams were prepared. First, the half-cell potentials were measured from the test specimens and they all ranged below -200 mV. Upon introduction of 3% salt solution, the potential reached up to -500 mV. This potential was maintained while a salt solution was being added for six months. The ECE technique was then applied to the test specimens in order to remove the chloride from them. Half-cell potential was measured to determine if the ECE technique can effectively reduce the level of corrosion.

Audit report on the City of Center Point, Iowa for the year ended June 30, 2014

Audit report on the City of Center Point, Iowa for the year ended June 30, 2014

Comparison of Roadway Roughness Derived from LIDAR and SFM 3D Point Clouds, HR-3001, 2015

This report describes a short-term study undertaken to investigate the potential for using dense three-dimensional (3D) point clouds generated from light detection and ranging (LIDAR) and photogrammetry to assess roadway roughness. Spatially continuous roughness maps have potential for the identification of localized roughness features, which would be a significant improvement over traditional profiling methods. This report specifically illustrates the use of terrestrial laser scanning (TLS) and photogrammetry using a process known as structure from motion (SFM) to acquire point clouds and illustrates the use of these point clouds in evaluating road roughness. Five roadway sections were chosen for scanning and testing: three gravel road sections, one portland cement concrete (PCC) section, and one asphalt concrete (AC) section. To compare clouds obtained from terrestrial laser scanning and photogrammetry, the coordinates of the clouds for the same section on the same date were matched using open source computer code. The research indicates that the technologies described are very promising for evaluating road roughness. The major advantage of both technologies is the large amount of data collected, which allows the evaluation of the full surface. Additional research is needed to further develop the use of dense 3D point clouds for roadway assessment.

Road Safety Audits for County Road X-23 from IA 2 to the South Corporate Limits of West Point and for County Road W-62 from US 218 to IA 27 in Lee County, Iowa, 2010

On October 20–21, 2009, two road safety audits were conducted in Lee County, Iowa: one for a 6 mile section of County Road X-23 from IA 2 to the south corporate limits of West Point and one for a 9.7 mile section of County Road W-62 from US 218 to IA 27. Both roads have high severe crash histories for the years of 2001 through 2008. Using these crash data, the Iowa Department of Transportation (Iowa DOT) has identified County Road X-23 as being in the top 5 percent of similar roads for run-off-road crashes. The Iowa DOT lists County Road W-62 as a high-risk rural road that has above-average crash numbers and is eligible for funding under the Federal High-Risk Rural Road Program. Considering these issues, the Lee County Engineer and Iowa DOT requested that road safety audits be conducted to address the safety concerns and to suggest possible mitigation strategies.

GPS to LRM: Integration of Spatial Point Features with Linear Referencing Methods, 2001

Global positioning systems (GPS) offer a cost-effective and efficient method to input and update transportation data. The spatial location of objects provided by GPS is easily integrated into geographic information systems (GIS). The storage, manipulation, and analysis of spatial data are also relatively simple in a GIS. However, many data storage and reporting methods at transportation agencies rely on linear referencing methods (LRMs); consequently, GPS data must be able to link with linear referencing. Unfortunately, the two systems are fundamentally incompatible in the way data are collected, integrated, and manipulated. In order for the spatial data collected using GPS to be integrated into a linear referencing system or shared among LRMs, a number of issues need to be addressed. This report documents and evaluates several of those issues and offers recommendations. In order to evaluate the issues associated with integrating GPS data with a LRM, a pilot study was created. To perform the pilot study, point features, a linear datum, and a spatial representation of a LRM were created for six test roadway segments that were located within the boundaries of the pilot study conducted by the Iowa Department of Transportation linear referencing system project team. Various issues in integrating point features with a LRM or between LRMs are discussed and recommendations provided. The accuracy of the GPS is discussed, including issues such as point features mapping to the wrong segment. Another topic is the loss of spatial information that occurs when a three-dimensional or two-dimensional spatial point feature is converted to a one-dimensional representation on a LRM. Recommendations such as storing point features as spatial objects if necessary or preserving information such as coordinates and elevation are suggested. The lack of spatial accuracy characteristic of most cartography, on which LRM are often based, is another topic discussed. The associated issues include linear and horizontal offset error. The final topic discussed is some of the issues in transferring point feature data between LRMs.