Optimal regionalization of wastewater treatment for water quality management

A mathematical decision model is developed which determines how a group of waste dischargers should regionalize their treatment facilities and the amount of treatment each facility should provide so that the cost of achieving a specified water quality goal is minimized. The waste dischargers are assumed to lie in a linear configuration along (or on both sides of) the river and several other regionalization restrictions are imposed. Treatment plant and piping costs as functions of wasteflow can be of any form and may include fixed costs. The model is solved by using a dual approach to nonlinear programming and is applied to data from the Delaware Estuary. The results compare favorably with previous regionalization schemes. The model is extended to consider branched systems and the use of bypass piping. Two additional minimum cost, regional wastewater treatment models are developed; one which finds the regional treatment facility pattern when degree of treatment is fixed and another which finds the regional facility pattern and uniform level of treatment for all facilities so that a water quality goal is met.U.S. Department of the InteriorU.S. Geological SurveyOpe

Governance of Steel and Kryptonite Politics in Contemporary Public Education Reform

Public education in the United States has been crippled by a combination of entrenched bureaucratic governance and special-interest politics. To remedy these failings, school districts, states, and the federal Education Department have adopted education reforms characterized by rigorous outcome-focused standards and assessments and the empowering of public schools, charter or otherwise, to meet the standards. Despite promising initial results, however, the reforms have been widely criticized, including by the populations they most seek to help. To explain this paradox, this Article first tries to assimilate the new education reforms to the most frequently proposed alternatives to bureaucratic governance — marketization, managerialism, professionalism and craft. It concludes, however, that none of these models adequately elucidates the reforms or provides an attractive alternative to special-interest politics, a crucial concomitant of bureaucracy. The Article claims that another governance model, democratic experimentalism, better explains the recent reforms and provides a richly participatory alternative to special-interest politics, which directly engages stakeholders — families and teachers, in this case — into its collaborative governance mechanisms. The Article finds, however, that the new education reforms have largely omitted the “democratic” part of experimentalism, resulting in the backlash by special interest groups and the constituents the reforms help the most, parents and students. The Article concludes by proposing a more fully democratic version of the reforms designed to improve student outcomes, powerfully engage key stakeholders, and diminish objections

Reliability of reservoir operation under hydrologic uncertainty

Sensitivity analyses were performed to examine typical stochastic programming (SP) modeling issues for a hypothetical single reservoir system. The elements considered include the partitions of inflow and storage states, the hydrologic characteristics of inflows, the types of system performance functions, and the tradeoffs between conflicting objectives. Simulation studies were conducted to verify the modeling outcomes and to provide insights for possible improvements of the system performance. Results from these analyses show that (1) both the numbers and the discrete increment values of the inflow and storage states affect an SP model's accuracy; (2) the uncertainty associated with the coefficients of variation of the inflows consistently has a greater impact on the system performance than the influence of the serial correlations; (3) in a sample study with flood control being the only objective, the use of either a convex function or a concave function alone for flood damages will not lead to an optimal operation policy which always prevents excessive flood release when there exists some unused storage space in the reservoir; (4) the preferences between the conflicting objectives have been shown to affect both the expected system performance and the individual operation decisions; and (5) modification of the discrete optimal solution, using a simple interpolation scheme, may improve the reservoir performance without resorting to a more complex model. A case study of Lake Shelbyville, Illinois was conducted based on the findings of sensitivity analyses for the hypothetical reservoir system using SP. An -- ad hoc approach was used to estimate accurately the agricultural and property damages in the optimization procedure. The optimal pool levels of Lake Shelbyville in the summer months were found to be roughly 2 to 5 ft lower than the current target level which is 599.7 ft. When the summer pool was forced to reach this target level using a penalty function approach in the SP model, the annual expected damages would increase by 9%. Generally, it would take more than one month for Lake Shelbyville to resume the summer pool from the winter drawdown level. Therefore, a transition period longer than one month between the winter drawdown and the summer recovery of lake levels is recommended for consideration if future modification is made in the rule curve.U.S. Geological SurveyU.S. Department of the InteriorOpe

TB167: Management and Winter Hardiness of Hairy Vetch in Maine

The research presented here describes a set of three different experiments that sought to establish appropriate management practices for hairy vetch in Maine, and to determine whether variability for winter hardiness exists among germplasm available commercially or from gene banks. Specific objectives of the first experiment were to evaluate effects of planting date and companion crop on crop and weed dry weight and total above-ground N content, at two sites differing in drainage. In a second experiment, the winter hardiness of hairy vetch from six commercial sources and the effect of a rye companion crop on hardiness were evaluated. In a third experiment, 69 V. villosa accessions from three gene banks were evaluated for winter hardiness, vigor, flowering date, and seed production.https://digitalcommons.library.umaine.edu/aes_techbulletin/1043/thumbnail.jp

Flood plain management through allocation of land uses–a dynamic programming model

Despite heroic structural measures, flood damages continue to rise. This research develops a means for identifying more nearly optimal patterns of land use with particular reference to timing, depth, and duration of flooding. The major premise is that flood plain management is best viewed as a problem of allocating land uses to land parcels. A dynamic programming model is developed to determine what combination of downstream uses, which require flood protection, and upstream uses, which may increase runoff or provide protection through longer water retention, should be encouraged. The dynamic programming model and an associated simplified routing technique are demonstrated on a real watershed. Desirable extensions of the model are identified. One major result of the project is the realization of a need to classify watersheds by the degree of effective interdependence among land use decisions so as to determine the most appropriate types of analytical model s and public sector interventions for particular cases. Thinking about flood management as a problem of land use allocation is shown to be a fruitful conceptualization for exploring the issues, for developing models, and for identifying appropriate public sector interventions.U.S. Geological SurveyU.S. Department of the InteriorOpe

What Is the Evidence that Riboflavin Can Be Used for Migraine Prophylaxis?

Individuals with migraine often have recurrent, painful symptoms, and symptomatic treatments have detrimentalside effects and do not prevent further attacks. Studies indicate that riboflavin can be used to decrease headachefrequency and lessen the need for symptomatic treatment. Mitochondrial dysfunction may play a role in migrainepathogenesis by interfering with oxygen metabolism. Daily doses of riboflavin, vitamin B2, may improve mitochondrialfunction by increasing the reserve of brain mitochondrial energy, and there are minimal side effects with dailytreatment. However, there is a need for further randomized, double-blind controlled studies to determine the effectivedose. Although riboflavin may not fully eliminate migraine nor take effect for several months, riboflavin is apromising prophylactic agent with minimal adverse effects that may significantly reduce the frequency of migraine

What Can We Learn about Neighborhood Effects from the Moving to Opportunity Experiment?

Experimental estimates from Moving to Opportunity (MTO) show no significant impacts of moves to lower‐poverty neighborhoods on adult economic self‐sufficiency four to seven years after random assignment. The authors disagree with Clampet‐Lundquist and Massey's claim that MTO was a weak intervention and therefore uninformative about neighborhood effects. MTO produced large changes in neighborhood environments that improved adult mental health and many outcomes for young females. Clampet‐Lundquist and Massey's claim that MTO experimental estimates are plagued by selection bias is erroneous. Their new nonexperimental estimates are uninformative because they add back the selection problems that MTO's experimental design was intended to overcome.Economic

Cropping System Diversification Reduces Severity and Incidence of Soybean Sudden Death Syndrome Caused by Fusarium virguliforme

Current management of sudden death syndrome (SDS) of soybean, caused by Fusarium virguliforme, focuses on planting resistant varieties and improving soil drainage; however, these measures are not completely effective. A 6-year study evaluated the effects of cropping system diversification on SDS and soybean yield. SDS, root health, yield, and F. virguliforme density in soil were assessed in a naturally infested field trial comparing a 2-year cropping system consisting of a corn-soybean rotation and synthetic fertilizer applications with 3- and 4-year cropping systems consisting of corn-soybean-oat + red clover and corn-soybean-oat +alfalfa-alfalfa rotations, respectively, with both manure and low synthetic fertilizer rates. In 5 of 6 years, SDS incidence and severity were lower and yield higher in the 3- and 4-year systems than in the 2-year system. SDS severity and incidence were up to 17-fold lower in the diversified systems than in the 2-year system. Incidence and severity of SDS explained 45 to 87% of the variation in yield. Plants in the 2-year system generally showed more severe root rot and lower plant weights than plants in the diversified systems. F. virguliforme density in soil was up to fivefold greater in the 2-year system compared with the 4-year system. The processes responsible for the suppression of SDS and yield protection in the diversified cropping systems still need to be determined