849 research outputs found
Brain-based Learning: Implications for the Elementary Classroom
Recent developments in neuroscience have enabled scientists to understand and image brain activity. Brain researchers are now more able than ever before to understand how the brain works, what affects the brain, and what implications these discoveries have for education. Based upon these discoveries new methods of teaching have been devised using the term, brain-based strategies or brain-based learning. This thesis examines some of the brain-based strategies embraced by leaders in this field. It will pay particular attention to the enriched environment, the effect of emotion on learning, and the concept of sensitive or critical periods. It will examine research in these areas and contemplate the validity of findings and the implications they have on classroom practice
Pullorum Disease Control and Eradication
Pullorum disease is recognized as a major disease entity among poultry in this country. Since the discovery of the etiologic agent in 1899, our knowledge concerning the nature of the disease has increased greatly through scientific investigation. These scientific findings have formed a basis for the formulation and application of an effective control and eradication program
Dedicated exhaust gas recirculation applied to a rich burn industrial natural gas engine
2020 Fall.Includes bibliographical references.Rich burn natural gas engines provide power for industrial applications such as gas compression. In this application where exhaust oxides of nitrogen (NOx) requirements can be critical, rich burn engines offer best in class aftertreatment emission reduction and operating cost capabilities by using a non-selective catalyst reduction (NSCR) or three-way catalyst system. However, due to high combustion temperatures associated with near stoichiometric air-fuel ratio (AFR) operation, rich burn engines are limited in brake mean effective pressure (BMEP) by combustion temperature. Consumers in the gas compression application are left to choose between engines that are capable of meeting even the most stringent emission requirements (rich burn) and engines with high BMEP rating (lean burn). Charge dilution by way of excess air (lean burn) or exhaust gas recirulation (EGR) is a common method used to lower combustion temperature with the purpose of limiting the production of engine out NOx. Conventional configurations of EGR consist of high pressure loop (HPL) and low pressure loop (LPL), each of which rely on components exposed to relatively high temperatures to control the impact that EGR has on combustion. Dedicated EGR is a novel variant of conventional EGR configurations which allows for the impact that EGR has on combustion to be controlled by components exposed to ambient temperature natural gas while also lowering rich burn combustion temperatures. Due to the lack of published research on dedicated EGR applied to industrial natural gas engines and consumer driven need for technologies to increase rich burn industrial natural gas engine BMEP this work represents an initial investigation into challenges associated with and capabilities of dedicated EGR. A Chemkin chemical kinetics model using the SI Engine Zonal, Flame Speed Calculator, and Equilibrium models was developed to quantify dedicated cylinder exhaust composition, laminar flame speed, and equilibrium combustion composition, respectively. The Aramco 2.0 mechanism was used for natural gas kinetics and was modified to include Zel'dovich mechanism for NOx formation. Engine experiments were conducted using a Caterpillar G3304 rich burn natural gas engine modified to operate with and without dedicated EGR. Initial tests that included power sweeps at fixed dedicated cylinder AFR revealed that operating conditions appropriate for dedicated EGR gasoline engines were not suitable for dedicated EGR natural gas engines. A response surface method (RSM) optimization was performed to find improved operating conditions at part load, 3.4 bar BMEP. Results showed that advanced spark timing and slightly rich dedicated cylinder AFR were optimal to achieve decreased coefficient of variance of indicated mean effective pressure (COV IMEP) and balanced cylinder IMEP output. In order to assess how operating with dedicated EGR would affect the performance of a NSCR system at 6.7 bar BMEP and fixed operating conditions engine AFR was swept between rich and lean conditions to quantify catalyst reduction efficiency and find the emissions compliance window. Without intentional AFR dithering the emissions compliance window was increased significantly. Finally, using best operating conditions from the RSM optimization and engine AFR sweep tests engine BMEP was increased beyond the 6.7 bar rating to find the possible increase in power density resulting from dedicated EGR
Everyday Peace in the Ecovillage: Unity and Strength through Diversity
Abstract:
Peace and conflict studies can benefit from studying small, ordinary, peaceful communities, in contrast to focusing on outlier events of violence, conflict and war. As a peace from below approach, the ecovillage model offers insights on how ordinary people innovate new ways to build and sustain peace within a microcosm of society, focusing intensely on the local. The aim of this research is to compare the everyday peace practices in two ecovillages, one in the United States and one in Ghana, how aspects of class, culture and race affect these practices, and what transformations can be seen toward positive peace as a result.
Through nine semi-structured interviews with ecovillage members, supplemented with documents and field notes, similar everyday peace practices were discovered. Key findings suggest that in both ecovillages, developing social cohesion through a clearly stated purpose and meaningful daily social interactions, is most fundamental, while dialogue is the most versatile and transformational practice for deepening understanding and promoting peace. Embracing diversity as a benefit for all, helps to transcend histories of oppression and create unity. Narratives revealed stories of transformation of improved financial stability, personal development and unifying relations between groups.
Key Words: Ecovillage, Everyday Peace, Conflict, Positive Peac
The Christianization of Judith: Considering the Hieronymian Translation of Liber Iudith and Jerome’s Christianizing Agenda
I will consider Jerome’s translation using gendered analysis while considering carefully how hints of his own preoccupations and Christianizing agendas can be found within. In Liber Iudith, Jerome gives a night’s work to a text illustrating the story of the Hebrew widow Judith single-handedly overcoming the seemingly unassailable Assyrians. Comparing Jerome’s translation to the earlier Septuagint text, a number of significant departures can be located. These departures demonstrate Jerome’s conception of proper Christian widowhood, related too to his qualms with femininity. The Hieronymian changes then appear to be both culturally-motivated and implemented in response to the demands of an increasingly Christian world.[1]
[1] K. F. B. Fletcher, “Hyginus’ Fabulae: Toward a Roman Mytholography,” in Writing Myth: Mythography in the Ancient World, ed. S. Trzaskoma and R. Scott Smith (Leuven: Peeters, 2013), 135; although Fletcher applies this theoretical approach to the first-century BCE author Hyginus, the framework can also be applied to Jerome’s translation of the Latin Vulgate
Influence of variations in penetrating solar radiation on the diurnal and intraseasonal structure of the oceanic boundary layer, The
2010 Summer.Includes bibliographical references.The upper portion of the ocean is fairly well mixed and turbulent. The turbulence within the ocean boundary layer (OBL) is regulated by many mechanisms. One process that is receiving a renewed interest is the effect of penetrating component of surface shortwave radiation on ocean dynamics. The influence of solar radiation has been parameterized in two ways. A limited set of models force all the incoming solar radiation to be absorbed in the top model layer. The second parameterization assumes that the irradiance (light) at a given level follows a multiple term exponential. Most commonly it is assumed that shortwave radiation is absorbed in two bands: visible and near infrared. The strength of the infrared absorption is assumed to be fixed. For the visible band, absorption depends on water clarity. Until recently, water clarity could take six different values (Jerlov water types). On climate scales, spatial and temporal variations in water clarity, based on surface chlorophyll, have a strong impact on the simulated ocean temperature, salinity, and momentum. For example, the sea surface temperature (SST) in the cold tongue is reduced. In addition, the strength of the Walker circulation is increased. However, this response is not consistent among different models and parameterizations. When chlorophyll is predicted, the influence of vertically variable water clarity on the thermodynamic and dynamic fields of the ocean can be examined. Studies that have incorporated an ecosystem model find minimal changes relative to using observed surface chlorophyll. Previous research has focused on longer climate time scales and most models do not consider vertical variations in water clarity. In this study the response of the ocean to diurnal and intraseasonal variations of water clarity is examined. The sensitivity to vertical variations in water clarity is also considered. To study the impact of variable solar radiation a model that accurately represents upper ocean physics is required. A new ocean mixing model is proposed that addresses some of the known deficiencies in previous models. The new model predicts entrainment based on turbulence at the OBL base, unlike other ocean models. An over prediction of the vertical heat flux in previous mixed layer models is avoided. The model framework discussed can be easily extended to any coordinate system. Further, this model can be coupled to an ocean biological model, which would determine the water clarity with depth, in a natural way. An evaluation of the new model against observations and a newly developed vector vorticity large eddy simulation (LES) model has shown that the new model preforms as well or better than previous OBL models in certain circumstances. This is especially with low vertical resolution. Since this version of the new model is local, it does not perform as well in pure convective simulations as OBL models with non-local forcing In this new model and K-Profile Parameterization (KPP), the temperature and velocity is very sensitive to variations in water clarity. Trapping more heat near the surface increases the temperature near the surface and confines daytime momentum input to a shallow layer. In addition, the depth of the thermocline is reduced as water clarity decreases. The simulated temperature and velocity fields are insensitive to subsurface variations in water clarity. The responses of the new model and KPP are similar when the turbidity of the column is taken as the near surface average. Two-dimensional simulations examining the influence of spatially variable turbidity lead to a slightly deeper thermocline and weaker near surface velocity relative to simulations with a zonally constant water clarity. It is found that models must allow solar radiation to penetrate beyond the top model level. Further, water clarity should be diagnosed from observed or predicted surface chlorophyll instead of the six Jerlov water types
Physiological and Nutritional Characterization of High Yield Soybean
Soybean [Glycine max (L.) Merr.] grain yields greater than three times the national average have been reported in yield contests. Characterization of soybean in a maximum yield environment is necessary to provide empirical data to support those yield claims and to provide an understanding of the physiological processes at that yield level. From 2011 to 2013, research characterized biomass and N accumulation rates, radiation use efficiency (RUE), leaf N dynamics, the rate of harvest index increase (dry matter allocation coefficient, DMAC), seedfill period (SFP), and grain yield components from Mr. Kip Cullers\u27 contest fields and in small plots at the University of Arkansas in Fayetteville. The greatest cultivar mean yield was 7953 kg ha-1, which occurred in 2013 when biomass and N accumulation rates and RUE values as high as 64.3 g m-2 d-1, 2.08 g N m-2 d-1, and 1.89 g MJ-1 were observed, respectively. These observed crop growth characteristics were near or above the maximum values previously reported in the literature. The DMAC and SFP values were also abnormally slow and long, respectively. This coupled with the enhanced growth rates provide empirical data and insights into the production of yields \u3e6419 kg ha-1 (100 bushels acre-1).
Additional research in Fayetteville evaluated the yield effects of several of Mr. Cullers\u27 alternative management practices. Management practices evaluated included various seed treatments, intentional herbicide injury, uniform plant spacing and emergence, lodging prevention, and a proprietary foliar-applied product. None of these alternative practices were effective in increasing yields beyond the high input practices utilized within this maximum yield environment.
The feasibility of several of these high input maximum yield management practices in large production fields in eastern Arkansas were evaluated. Enhanced management including
additional inputs of poultry litter, irrigation, supplemental N, and pest control were evaluated on the field scale. Two cultivars had average yields of 6931 and 6986 kg ha-1 at the England location in 2013. Economic analysis suggested that even this scaled down maximum yield management was less profitable than the growers\u27 normal production practices.
Finally, a simple soybean crop model was used to simulate crops grown within maximum yield environments at Fayetteville and Mr. Cullers\u27 contest fields. Sensitivity analyses were also conducted to examine the effects of varying values of RUE, N accumulation, specific leaf N (SLN), and DMAC. The most accurate dataset was for Fayetteville in 2012 and 2013 and the default parameters in the model predicted yields 34.0% less than observed over all cultivars. Modifying the model with the observed parameters for RUE, N accumulation, and SLN resulted in yield predictions that averaged 3.4% greater than the observed for all the cultivars in Fayetteville in 2012 and 2013. Sensitivity analyses indicated that yield could be increased with decreased DMAC values, increased RUE values, increased SLN values when coupled with greater N accumulation rates, and with increasing N accumulation when coupled with increasing RUE values
Hackerville: A laboratory environment for security literacy
Teenage internet usage is on the rise. With the increase in activity comes a need to train students to be secure online. But awareness campaigns and top ten lists aren\u27t enough. With the ever evolving attack vectors, students need to be able to adapt and recognize potentially malicious attacks. Literacy is therefore the best course of action when teaching students how to be safe and secure online. And a course will need to have a hands-on component, so that students can experience attacks in a safe and secure environment, as well as be able to recognize attacks when they happen.
The objective of this paper is to create a lab framework to be used with a security literacy course. This framework will be modular, with the ability to add new modules as new attacks, and new types of websites come about. The lab will need to have the ability to evolve with the ever-changing attack landscape. In this paper, I present, in detail, how this framework works, and what components are necessary to make this framework successful
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