142 research outputs found
Seats: A Business Plan
Every year over 88 million people participate in recreational boating on lakes all across the U.S. (http://www.statista.com/topics/1138/recreational-boating/). While enjoying their favorite aquatic activities, these people have needs and desires just like any other time in life, but with a relatively high opportunity cost to acquire goods. Making a trip to the marina and back costs both money and time that boaters would rather be spending having fun with family and friends. The Seats model, a mobile vending vessel, will fill this gap, providing food necessities and a fun environment that does not require boaters to dock their boat in order to obtain any forgotten goods. Our vessel will be stocked with the items boaters forgot to pack and will make its way around the lake--attracting crowds of lake-goers who are hungry, looking for a good time, or both. The Seats model will begin operation at Beaver Lake in Northwest Arkansas, and eventually spread to lakes across the United States
Risk Factors For Congenital Heart Defects in Saudi Arabian Infants
Two studies were undertaken. Firstly, congenital heart defect (CHD) data from the Saudi Arabian Congenital Heart Defects registry (CHD registry) were compared to data published by the Baltimore-Washington Infant Survey (BWIS) group and the European Surveillance of Congenital Anomalies registry (EUROCAT). Distributions of CHD diagnoses within the Saudi Arabian dataset (Riyadh region and Saudi Arabia as a whole) were similar to those from these more comprehensive efforts, providing evidence for the completeness and accuracy of the CHD registry, for Riyadh region in particular. Secondly, an unmatched case-control study of risk factors for all structural congenital heart defects in children resident in Riyadh, Saudi Arabia was undertaken. The primary exposure of interest was consanguinity up to and including third cousins. Incident cases were identified from the CHD Registry from June 1, 2002 to December 31, 2004. Controls were obtained from the Well Baby Clinic, Riyadh Anned Forces (Military) Hospital. Using a detailed and reverse translated questionnaire, a face to face interview was conducted with 235 case and 247 control mothers by research assistants fluent in the local dialect. Mothers were asked to consider their exposure to risk factors within the period of 3 months prior to and 3 months post conception. Consanguinity was collected by phylogram method. The majority of mothers were interviewed when the infant was less than one year of age. Analyses were conducted using four different case groups: all cases, isolated cardiac cases, and embryological earliest and latest cases. Twenty five percent of cases and controls were first cousins or closer. Sixteen percent of cases versus 13 percent of controls were first cousins once removed or equivalent and 12 percent of both cases and controls were second 01' third cousins. Consanguinity was not found to increase the risk of CHD in this population. The adjusted odds ratio for all cases was 1.0 (CI9S=O.7-1.7) and for isolated cardiac cases it was 1.2 (CI9S=O.7-2.0). Statistically significant associations were found for other exposures such as previous pregnancy losses, maternal age, multiplicity, maternal use of hair dyes and pesticides sprayed in the house, confirming findings from previous studies. It is unlikely that the findings for consanguinity can be explained by misclassification of exposure or, in the analysis of all cases, low statistical power
Demonstration of decomposition and optimization in the design of experimental space systems
Effective design strategies for a class of systems which may be termed Experimental Space Systems (ESS) are needed. These systems, which include large space antenna and observatories, space platforms, earth satellites and deep space explorers, have special characteristics which make them particularly difficult to design. It is argued here that these same characteristics encourage the use of advanced computer-aided optimization and planning techniques. The broad goal of this research is to develop optimization strategies for the design of ESS. These strategics would account for the possibly conflicting requirements of mission life, safety, scientific payoffs, initial system cost, launch limitations and maintenance costs. The strategies must also preserve the coupling between disciplines or between subsystems. Here, the specific purpose is to describe a computer-aided planning and scheduling technique. This technique provides the designer with a way to map the flow of data between multidisciplinary analyses. The technique is important because it enables the designer to decompose the system design problem into a number of smaller subproblems. The planning and scheduling technique is demonstrated by its application to a specific preliminary design problem
The recoverability of fingerprints on paper exposed to elevated temperatures - Part 1: comparison of enhancement techniques
This research investigates the recoverability of fingerprints which have been exposed to elevated temperatures in order to mimic the environment a piece of paper may be exposed to within an arson scene. Arson is an expensive crime, costing the UK economy, on average, £53.8 million each week [1]. Anything which may give rise to the identity of the fire setter should be analysed and as such, unburnt paper may be a potential source of fingerprints. While it is true that even a moderate fire will obscure and render partially useless some types of evidence, many items, including fingerprints, may still survive [2-4]. This research has shown that fingerprints are still retrievable from paper which has been subjected to the maximum testing conditions of 200˚C for 320min. In fact, some fingerprints naturally enhance themselves by the heating process. This investigation has also shown that the most effective enhancement technique was found to be 1,8-diazafluoren-9-one (DFO) for exposure temperatures upto 100˚C. Physical developer (PD) is the most effective enhancement technique for exposure temperatures from 100˚C to 200˚C. For porous surfaces, there are fingerprint development techniques which are effective at enhancing fingerprints exposed upto a temperature of 200˚C, irrespective of the firefighting extinguishing technique, as PD, in addition to developing fingerprints exposed to high temperatures, is one of the few processes which will enhance fingermarks on wetted surfaces
Dehydrative cyclizations via acid catalysis as a method for molecular diversity
Development of new synthetic methodologies that allow for efficient access to desirable core structures is a consistently valuable area of research for synthetic chemistry. Good methodologies provide rapid access to systematically varying compounds with desirable properties, enabling functional testing and the discovery of new, useful compounds and materials. Three novel synthetic methodologies that make use of dehydrative cyclizations of carbinols via Lewis acid catalysis have been developed towards this end: (1) A calcium-catalyzed, dehydrative, ring-opening cyclization of cyclopropyl carbinols to form (hetero)aryl-fused cyclohexa-1,3-dienes; (2) A Bi(OTf)3-catalyzed synthesis of α-alkylidene-γ-butyrolactones from the ring-opening cyclization of cyclopropyl carbinols; (3) A calcium-catalyzed synthesis of cyclopenta[b]thiophenes and indenes via dehydrative Nazarov-type electrocyclizations of alkenyl (hetero)aryl carbinols. The mechanistic details of how each of these methods perform have also been investigated. Initial results and proposals for consequent projects, which span the breadth of target synthesis and new methodologies, have also been established.Ph.D
The recoverability of fingerprints on paper exposed to elevated temperatures - Part 2: natural fluorescence
Previous work by the authors [1] investigated the recoverability of fingerprints on paper which had been exposed to elevated temperatures by comparing various chemical enhancement techniques (ninhydrin, 1,8-diazafluoren-9-one (DFO), and physical developer (PD)). During that study, it became apparent, as a consequence of observations made in operational work [2], that fingerprints on paper subjected to 150ËšC fluoresced under examination with green light of waveband 473-548nm with a 549nm viewing filter. This work examined the three types of prints (eccrine, sebaceous, and ungroomed) after 20 min exposure to the temperature range 110ËšC to 190ËšC (in 10ËšC increments) and found that the eccrine fingerprints fluoresced more brightly. This indicated that it was a component of the eccrine deposit which was causing the fluorescence. Luminance measurements found that the maximum fluorescence was experienced at 170ËšC on both types of paper. As a consequence, eccrine heat-treated fingerprints were viewed under violet-blue (350-469nm), blue (352-509nm), and green light (473-548nm) which indicated that the greatest luminance intensities were obtained under blue light and the smallest under green light. In order to determine what component of the eccrine fingerprint was causing this fluorescence, five of the most prevalent amino acids (alanine, aspartic acid, glycine, lysine, and serine) [3-4] were exposed to this temperature range. The luminance measurements were taken under exposure to the green light in order for the minimum fluorescence to be observed, with an assumption that blue-violet or blue illumination will provide brighter fluorescence in practice. The results indicated that four of the amino acids are behaving similarly across the temperature range, but with slightly different luminance measurements, but all are exhibiting some level of fluorescence. Thermal degradation products of alanine and aspartic acid have been suggested by Richmond-Aylor et al. [5]. The structure of these thermal degradation products is cyclic in nature, and as such, there is a possibility that two of these products would fluorescence. Sodium chloride and urea were also exposed to the temperature range and they also fluoresced to some extent. This work shows that eccrine fingerprints that have been exposed to temperatures of between 130ËšC to 180ËšC will fluoresce under violet-blue, blue, and green light. This level of fluorescence for ungroomed fingerprints is much less but this will be dependent on the individual, the more eccrine the deposit, the stronger the fluorescence. This work shows that the amino acids, sodium chloride, and urea present in fingerprint deposits are all contributing to the fluorescence of the print, but may not be the sole contributor as other eccrine components have not yet been tested
Risk factors for congenital heart defects in Saudi Arabian infants
Two studies were undertaken. Firstly, congenital heart defect (CHD) data from the Saudi Arabian Congenital Heart Defects registry (CHD registry) were compared to data published by the Baltimore-Washington Infant Survey (BWIS) group and the European Surveillance of Congenital Anomalies registry (EUROCAT). Distributions of CHD diagnoses within the Saudi Arabian dataset (Riyadh region and Saudi Arabia as a whole) were similar to those from these more comprehensive efforts, providing evidence for the completeness and accuracy of the CHD registry, for Riyadh region in particular. Secondly, an unmatched case-control study of risk factors for all structural congenital heart defects in children resident in Riyadh, Saudi Arabia was undertaken. The primary exposure of interest was consanguinity up to and including third cousins. Incident cases were identified from the CHD Registry from June 1, 2002 to December 31, 2004. Controls were obtained from the Well Baby Clinic, Riyadh Anned Forces (Military) Hospital. Using a detailed and reverse translated questionnaire, a face to face interview was conducted with 235 case and 247 control mothers by research assistants fluent in the local dialect. Mothers were asked to consider their exposure to risk factors within the period of 3 months prior to and 3 months post conception. Consanguinity was collected by phylogram method. The majority of mothers were interviewed when the infant was less than one year of age. Analyses were conducted using four different case groups: all cases, isolated cardiac cases, and embryological earliest and latest cases. Twenty five percent of cases and controls were first cousins or closer. Sixteen percent of cases versus 13 percent of controls were first cousins once removed or equivalent and 12 percent of both cases and controls were second 01' third cousins. Consanguinity was not found to increase the risk of CHD in this population. The adjusted odds ratio for all cases was 1.0 (CI9S=O.7-1.7) and for isolated cardiac cases it was 1.2 (CI9S=O.7-2.0). Statistically significant associations were found for other exposures such as previous pregnancy losses, maternal age, multiplicity, maternal use of hair dyes and pesticides sprayed in the house, confirming findings from previous studies. It is unlikely that the findings for consanguinity can be explained by misclassification of exposure or, in the analysis of all cases, low statistical power.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Development of the Multi-Purpose Transportation System for the Space Launch System (SLS) Core Stage (CS) Flight Article
NASA's Multi-Purpose Transportation System (MPTS) is designed to transport the Space Launch System (SLS) vehicle segments by waterway and roadway. It is tasked with transporting the vehicle from where it is manufactured to its intermediate test location and final launch destination. Its design incorporates mechanisms that release degrees of freedom to prevent excessive loading during transit and ensure a successful delivery of the vehicle to its intended destination. In addition to the Core Stage (CS) flight article, the system will also move three Structural Test Articles (STAs), the Dynamic Demonstration Unit (DDU), and a simulated CS Pathfinder (weight, center of gravity, outer mold line dimensions, and overall length) over road terrain at four NASA centers and on the Pegasus barge. The MPTS independently supports the article at both ends while operating as a combined unit through automated monitoring of its released degree of freedom and corrective responses. This allows the system to constrain its payload in a statically determinate manner while traversing highly variable terrain. Multi-body simulation of the transportation route is useful to predict free-body motion within its range of mobility. The MPTS has completed its design and analysis developmental cycles. This paper describes the design challenges encountered in developing this system of large-scale structure, which incorporates complex mechanisms. The unique techniques and methodologies developed for analytical assessment of the hardware are also discussed
Development of the Multi Purpose Transportation System for the Space Launch System (SLS) Core Stage (CS) Flight Article
NASAs Multi Purpose Transportation System (MPTS) is designed to transport the Space Launch System vehicle segments by waterway and roadway. It is tasked with transporting the vehicle from where it is manufactured to its intermediate test location and final launch destination. Its design incorporates mechanisms that release degrees of freedom to prevent excessive loading during transit and ensure a successful delivery of the vehicle to its intended destination. In addition to the CS (Core Stage) flight article, the system will also move three structural test articles and a simulated CS Pathfinder (weight, center of gravity, outer mold line dimensions, and overall length) over road terrain on four NASA centers and on the Pegasus barge. The MPTS independently supports the article at both ends while communicating as a combined unit through automated monitoring of its released degree of freedom and corrective responses. This allows the system to constrain its payload in a statically determinate manner while traversing across highly variable terrain. Multi-body simulation of the transportation route is useful to predict free-body motion within the specified travel ranges. The MPTS has completed its design and analysis developmental cycles. This unpublished paper will describe the design challenges encountered in developing this system of large scale structure which incorporates complex mechanisms. The unique techniques and methodologies developed for analytical assessment of the hardware will be also be discussed. Key results from analytical evaluations as well as ongoing performance testing will be presented
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