6,041 research outputs found
Exploring intraspecific life history patterns in sharks
Marine ecosystems compose the major source (85%) of world fisheries production (Garcia and Newton, 1997). Although only a few fish species tend to dominate fishery catches (Jennings et al., 2001), a large diversity of fishes
representing varied taxonomic levels, ecological guilds, and life histories is commonly taken. Recently, 66% of
global marine resources were determined to be either fully, heavily, or over-exploited (Botsford et al., 1997).
Considering the current state of many fisheries, the large diversity of species taken globally, and the general lack of resources to adequately assess many stocks, it has become important to develop shortcuts that may provide
methods fisheries scientists can use to determine which stocks are in danger of overexploitation and which recovery plans are appropriate when biological data are limited (Stobutzki et al., 2001)
Health Insurance in Nonstandard Jobs and Small Firms: Differences for Parents by Race and Ethnicity
Focuses on the higher rates of small-firm and nonstandard employment and of uninsurance regardless of job type among Latino/Hispanic and African-American parents. Considers healthcare reform provisions' effects on their insurance costs and coverage rates
Generalized Newton-Raphson trajectory optimization-generator 1
Computer program constructs a sequence of optimal solutions to dynamically-approximate linear equations. Specification of the number and type of subarcs in the optimal solution allows simultaneous satisfaction of all switching criteria
A Look At The Merchant Marine Act Of 1920: Is It Time For The U.S. To Change Course?
Due to recent changes in global shipping, we investigate the Merchant Marine Act of 1920 – also known as the Jones Act. When constructed, our governing body decided that the Act was necessary for the country’s naval defenses and for proper growth of foreign and domestic commerce. The plan was for the fleet to be owned and operated privately by citizens of the United States. However, in today’s economic conditions some are wondering if the Jones Act is a liability to foreign commerce. In our work, we explore the advantages of naval defense and shipbuilding as well as the disadvantages on commerce and U.S. transportation infrastructure. To conclude, we offer opinions for policy changes to create a more level playing field for the U.S. to compete in global logistics
Container Ship Routing: Panama Canal vs. U.S. Land Bridge
In our work, we investigate choices for container ship transportation from the eastern Pacific to the western Atlantic based solely on time. Choices include traveling through the Panama Canal or using the U.S. as a land bridge (via truck and rail car). A breakeven methodology, given vessel size, is employed to discriminate between paths. Interested parties of our work might include those investigating multi-modal integration opportunities, those seeking transportation efficiencies in water, truck and rail, and students as a case assignment in Transportation and Logistics courses
Flexible Resource Allocation: A Comparison Of Linear Diophantine Analysis And Integer Programming
To help production managers cope with an ever changing and complex business environment, we investigate a flexible methodology for solving integer resource allocation problems. Solutions obtained to an example problem using the Linear Diophantine Equation (LDE) methodology presented are compared to solutions produced using Integer Programming. Tradeoffs are examined and discussed, and suggestions are made for managers facing resource decisions similar to the example studied
Effects of radiation on charge-coupled devices
The effects of 1 MeV electron irradiation upon the performance of two phase, polysilicon aluminum gate CCDs are reported. Both n- and p-surface channel and n-buried channel devices are investigated using 64- and 128-stage line arrays. Characteristics measured as a function of radiation dose include: Transfer inefficiency, threshold voltage, field effect mobility, interface state density, full well signal level and dark current. Surface channel devices are found to degrade considerably at less than 10 to the 5th power rads (Si) due to the large increase in fast interface state density caused by radiation. Buried channel devices maintain efficient operation to the highest dose levels used
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