Prescribed fire has become a known silvicultural disturbance on public and private lands in the United States. Implementation of fire as a treatment allows land managers to reach specific goals through lower operational costs compared to mechanical or chemical means. Differences in management strategies for forested ecosystems often lead to individual plant species being overlooked. With an increasing number of invasive plants spreading into North American ecosystems, response of invasive plants to fire could potentially affect management decisions. It is important to understand the fire-response of invasive plants as stimulatory, neutral or suppressive to aid in future management of ecosystems. This study quantified the impact of small-scale prescribed fire on the invasive plant Japanese chaff flower (Achyranthes japonica; hereafter Chaff), at three different sites in Southern Illinois. The hypothesis was that fire would decrease the density and survival of chaff. Fixed sample plots were created (24 plots per site). At each site a set of unburned plots (control 8-16 plots) and treatment plots (burned 8-16 plots) were established, resulting in 32 burned plots and 32 unburned plots between 2015 and 2016. To best understand the effects fire had on Chaff, plant phenology was classified into four different life stages (cotyledons, seedlings, juveniles, adults) during each survey of the study plots. Using multi-model inference, one candidate model set was created to evaluate the survival of adult chaff flower, and 4 model sets to investigate the change in density of adults, juveniles, seedlings, and cotyledons respectively. The models had sites, treatment (burned versus unburned), and year (2015 and 2016) as explanatory variables. We compared the models using Akaike’s Information Criterion corrected for sample bias (AICc) to compare and rank models. The top model described survival of adult chaff flower, retained only treatment (burn vs. unburned) as a variable, and showed that Chaff survival was lower in burned plots than in unburned plots (β = -0.30, SE = 0.02), with the effect being greater at site 3 where about 46% of adult plants died after being treated with fire. The top model describing the change in adult plant density retained an interaction between year and site, and showed that adult chaff density increased from 2015 to 2016 on sites 1 and 2 by 32% and 14%, respectively. However, on site 3 there was nearly a 50% decrease in adult chaff flower plants in 2016. The juvenile and cotyledon stages showed similar results, by retaining an interaction between site and treatment, with an addition to year; the data showed a higher number of juveniles and cotyledons in the unburned plots than the burned plots going from 2015 to 2016. Seedling density decreased from 2015 to 2016 on sites 2 and 3, but on site 1 there was a slight increase. This increase could be largely due to the ability of the plants independent ability to replenish gaps in the population. Chaff can grow from the cotyledon class to an adult plant in a single growing season with sufficient sunlight, nutrient, and space. This study showed that a single entry of low intensity prescribed fire can kill established adult chaff plants. A single entry of prescribed fire had a direct negative impact on emerging young chaff plants, but the traits and characteristics of this invasive species which enable it to persist after a disturbance, as well as the documented variability on control associated with seasonal and local site differences, suggest that fire treatment alone may not be enough to halt its spread. Future work could focus on more burns, with repeated entry of fire in chaff flower populations and burns conducted at higher intensities and at different times of the year to further explore the impacts of fire on this invasive species.

The colors of the glumes on wheat have been described as being white, yellow, brown, or black. The white actually ranges from cream or pale straw-yellow to dark yellow. Some varieties have white or yellow glumes with brown or black nerves.

A study was conducted on an annual cropped field near Lanigan, Saskatchewan over two years (2005-2006, 2006-2007) to evaluate the effects of three extensive winter feeding systems (bale grazing (BG), swath grazing (SG) and straw-chaff grazing (ST-CH)) and one intensive winter feeding system (drylot (DL)) on cow performance, soil nutrients, crop yield and system cost of production.<p> Differences in BW (P<0.05) were observed during the 2005-2006 study period with the greatest difference occurring with cows in the SG feeding system. Cows grazing swaths (SG) had a BW loss of 8.0 kg over the 78 d trial period, however these cows consumed 15% less DM and 13% less TDN than cows bale grazing, grazing crop residue or fed in drylot pens. Differences in BW change (P<0.05) were also observed during Yr 2 between the cows fed drylot and cows grazing barley straw-chaff, 32.9 and 6.5 kg, respectively. This difference in body weight change (BW∆) and lower TDN consumption may be attributed to inaccessibility of the straw-chaff feed in the field, due to inclement weather and would suggest a lengthy acclimation period for extensive field grazing systems.<p> The effects of extensive winter feeding system on soil nutrients and soil structure were determined the following spring after winter grazing. NO3-N levels at the low slope position in the 0-15 cm depth were 53% higher on the BG sites than the ST-CH sites. This may be attributed to the larger concentration of feed, thus feed nutrients, in the BG feeding system. Phosphorus levels on the BG wintering sites were 34% higher than levels in the SG or ST-CH sites. Crop biomass measured on the BG sites was consistent with soil nutrients captured, resulting in a 15% increase in biomass compared to ST-CH and SG sites. Soil nutrient and crop biomass distribution was consistent among winter grazing sites with the ST-CH sites having the most uniform distribution of nutrients and crop biomass, and the BG sites having the least.

Electrical wiring on board aircraft has raised serious weight and safety concerns in the aerospace industry. Wires are antenna. It may also cause interference to radio-based systems on the aircraft, or, in the case of military aircraft, create a "signature" that can be detected by enemy receivers. Wireless application in avionic system helps reducing the total weight and reconfigurable of the aircraft; hence, lower the fuel costs, installation cost and maintenance costs, as well as the “signature” of the aircraft. The focus of this thesis, therefore, is to study the feasibility of different wireless standards, namely Wi-Fi, Bluetooth and ultra-wide band (UWB), on replacing the wired data connection in the EW countermeasure or chaff/flare dispenser systems. The study was constructed under the supervision of the department of Electronic Defense System, Saab AB in Järfalla, Stockholm. The discussion will be based on the resource availability, the reliability, the stability and the security of the wireless system relative to an avionic application; i.e., whether wireless links will negatively affect the overall reliability and safety of the aircrafts. Due to the theoretical studies and results from the simulation, we studied the feasibility issue and concluded that UWB is the most appropriate choice of wireless communication for non-critical aerospace applications, comparing with Wi-Fi and Bluetooth. UWB links can have reasonable immunity to interferences, low interference to other on-board wireless systems, and good security performance.

A study was conducted on an annual cropped field near Lanigan, Saskatchewan over two years (2005-2006, 2006-2007) to evaluate the effects of three extensive winter feeding systems (bale grazing (BG), swath grazing (SG) and straw-chaff grazing (ST-CH)) and one intensive winter feeding system (drylot (DL)) on cow performance, soil nutrients, crop yield and system cost of production.<p> Differences in BW (P<0.05) were observed during the 2005-2006 study period with the greatest difference occurring with cows in the SG feeding system. Cows grazing swaths (SG) had a BW loss of 8.0 kg over the 78 d trial period, however these cows consumed 15% less DM and 13% less TDN than cows bale grazing, grazing crop residue or fed in drylot pens. Differences in BW change (P<0.05) were also observed during Yr 2 between the cows fed drylot and cows grazing barley straw-chaff, 32.9 and 6.5 kg, respectively. This difference in body weight change (BW∆) and lower TDN consumption may be attributed to inaccessibility of the straw-chaff feed in the field, due to inclement weather and would suggest a lengthy acclimation period for extensive field grazing systems.<p> The effects of extensive winter feeding system on soil nutrients and soil structure were determined the following spring after winter grazing. NO3-N levels at the low slope position in the 0-15 cm depth were 53% higher on the BG sites than the ST-CH sites. This may be attributed to the larger concentration of feed, thus feed nutrients, in the BG feeding system. Phosphorus levels on the BG wintering sites were 34% higher than levels in the SG or ST-CH sites. Crop biomass measured on the BG sites was consistent with soil nutrients captured, resulting in a 15% increase in biomass compared to ST-CH and SG sites. Soil nutrient and crop biomass distribution was consistent among winter grazing sites with the ST-CH sites having the most uniform distribution of nutrients and crop biomass, and the BG sites having the least.

No estudo da complexidade de problemas computacionais destacam-se duas classes conhecidas como P e NP. A questao P=NP e um dos maiores problemas nao resolvidos em Ciencia da Compu- tacao teorica e Matematica contemporanea. O problema SAT foi o primeiro problema reconhecido como NP-completo e consiste em verificar se uma determinada formula da logica proposicional clas- sica e ou nao satisfazivel. As implementacoes de algoritmos para resolver problemas SAT sao conhe- cidas como resolvedores SAT (SAT Solvers). Existem diversas aplicacoes em Ciencia da Computacao que podem ser realizadas com SAT Solvers e com outros resolvedores de problemas NP-completos que podem ser reduzidos ao SAT como por exemplo problemas de coloracao de grafos, problemas de agendamento e problemas de planejamento. Dentre os mais eficientes algoritmos para resolvedores de SAT estao Sato, Grasp, Chaff, MiniSat e Berkmin. O Algoritmo Chaff e baseado no Algoritmo DPLL o qual existe a mais de 40 anos e e a estrategia mais utilizada para os Sat Solvers. Essa dissertacao apresenta um estudo aprofundado do comportamento do zChaff (uma implementacao muito eficiente do Chaff) para saber o que esperar de suas execucoes em geral . / In the study of computational complexity stand out two classes known as P and NP. The question P = NP is one of the greatest unsolved problems in theoretical computer science and contemporary mathematics. The SAT problem was first problem recognized as NP-complete and consists to check whether a certain formula of classical propositional logic is satisfiable or not. The implementations of algorithms to solve SAT problems are known as SAT solvers. There are several applications in computer science that can be performed with SAT solvers and other solvers NP- complete problems can be reduced to SAT problems such as graph coloring, scheduling problems and planning problems. Among the most efficient algorithms for SAT solvers are Sato, Grasp, Chaf, MiniSat and Berkmin. The Chaff algorithm is based on the DPLL algorithm which there is more than 40 years and is the most used strategy for Sat Solvers. This dissertation presents a detailed study of the behavior of zChaff (a very efficient implementation of the Chaff) to know what to expect from their performance in general.

No estudo da complexidade de problemas computacionais destacam-se duas classes conhecidas como P e NP. A questao P=NP e um dos maiores problemas nao resolvidos em Ciencia da Compu- tacao teorica e Matematica contemporanea. O problema SAT foi o primeiro problema reconhecido como NP-completo e consiste em verificar se uma determinada formula da logica proposicional clas- sica e ou nao satisfazivel. As implementacoes de algoritmos para resolver problemas SAT sao conhe- cidas como resolvedores SAT (SAT Solvers). Existem diversas aplicacoes em Ciencia da Computacao que podem ser realizadas com SAT Solvers e com outros resolvedores de problemas NP-completos que podem ser reduzidos ao SAT como por exemplo problemas de coloracao de grafos, problemas de agendamento e problemas de planejamento. Dentre os mais eficientes algoritmos para resolvedores de SAT estao Sato, Grasp, Chaff, MiniSat e Berkmin. O Algoritmo Chaff e baseado no Algoritmo DPLL o qual existe a mais de 40 anos e e a estrategia mais utilizada para os Sat Solvers. Essa dissertacao apresenta um estudo aprofundado do comportamento do zChaff (uma implementacao muito eficiente do Chaff) para saber o que esperar de suas execucoes em geral . / In the study of computational complexity stand out two classes known as P and NP. The question P = NP is one of the greatest unsolved problems in theoretical computer science and contemporary mathematics. The SAT problem was first problem recognized as NP-complete and consists to check whether a certain formula of classical propositional logic is satisfiable or not. The implementations of algorithms to solve SAT problems are known as SAT solvers. There are several applications in computer science that can be performed with SAT solvers and other solvers NP- complete problems can be reduced to SAT problems such as graph coloring, scheduling problems and planning problems. Among the most efficient algorithms for SAT solvers are Sato, Grasp, Chaf, MiniSat and Berkmin. The Chaff algorithm is based on the DPLL algorithm which there is more than 40 years and is the most used strategy for Sat Solvers. This dissertation presents a detailed study of the behavior of zChaff (a very efficient implementation of the Chaff) to know what to expect from their performance in general.

Master of Science / Department of Grain Science and Industry / Kingsly Ambrose / Consistent and reliable flow of bulk wheat from hoppers and silos is very significant in wheat handling and processing. Bulk wheat flow challenges such as inconsistent flow, arching, etc., are common during handling. The irregular size and non-uniformity of physical properties, the presence of impurities affects the flow behavior during discharge. Chaff and insects infested kernels are the two most common impurities present in wheat. In this research, the effect of these two impurities on their physical and flow properties of wheat were studied. Physical and flow indicators, such as bulk, tapped, particle densities, angle of repose, Hausner’s ratio, Carr index, and porosity measures the flowability of uncompacted bulk solids. Meanwhile, flow properties tested by shear testing principle based on Jenike’s method, simulated bulk wheat under pressure in bins/hoppers. The dynamic properties tested quantify the energy required to flow, compressibility and permeability at dynamic handling situations. Due to the presence of impurities and moisture content differences, bulk density and angle of repose of wheat varied from 801.54kg/m3 to 718.36kg/m3, and 23.6° to 38.4°, respectively. Angle of internal friction and wall friction angle that reflect interaction between particles and particle with bins/hopper walls, ranged from 23.95° to 43.13° and 15.46° to 20.33°, respectively. In addition to instrumental flow property evaluation, the flow profile, discharge rate, and particle velocity during hopper flow of bulk wheat was studied using Particle Image Velocimetry method. Mass flow and funnel flow hopper dimensions were used for this flow profile analysis. The discharge rate decreased from 1.67 to 1.12 kg/s for mass flow and 1.42 to 0.86 kg/s for funnel flow when the chaff in bulk wheat increased from 0% to 7.5% (weight basis). Analysis of the active flow zone indicated that bulk wheat without chaff had a uniform flow compared to wheat with chaff in the bulk. The findings from this study will be useful for design of hopper bottom bins and handling equipment based on the wheat quality and percent moisture content.

名古屋大学年代測定総合研究センターシンポジウム報告

In this thesis, trajectory computations of chaff particles ejected from a medium weight utility helicopter are performed using computational fluid dynamics. Since these chaff particles are ejected from a helicopter and carried by its flow field, it is necessary to compute and include the effects of the helicopter flow field in general and engine hot gases, main and tail rotor wakes in particular. The commercial code FLUENT is used for flow field and trajectory computations. Both main rotor and tail rotor are simulated by the so-called Virtual Blade Model in a transient fashion. Flows through the engine inlets and exhausts are treated via appropriate boundary conditions in the analysis. The generic ROBIN geometry is studied first in order to assess the accuracy of the Virtual Blade Model and various turbulence models. The computational solutions related to the ROBIN geometry are validated against the available experimental data. Flowfield and trajectory computations of chaff particles are done at a forward flight condition at which certain flight data and chaff trajectory data were acquired by ASELSAN, Inc. In the flight test, three successive chaff decoy ejections were conducted, and the chaff cloud distributions were recorded by two high-speed cameras positioned on two different locations on the helicopter. Numerical calculations employ the post-processed camera recordings for setting the initial distributions of the chaff particles. Then, the computational results related to the chaff particle trajectories are validated by comparing to the recorded transient chaff cloud distributions from the ASELSAN flight test. For post-processing of the recorded chaff distributions, an experimental analysis commercial code called TrackEye is used. It is found that the numerical simulations capture the trends of chaff particle distributions reasonably well.