ATTITUDE DETERMINATION OF A STUDENT SATELLITE USING ON-ORBIT MAGNETOMETER AND TEMPERATURE DATA

An extended Kalman filter is modified to support only magnetometer data as a measurement for spacecraft attitude information. Actual on-orbit data from a student satellite is used in the filter from three different time periods and varying data frequencies. The extended Kalman filter has a thermal model that utilizes external temperature data as a verification tool for filter convergence and for parameter tuning. It can capture the frequency of temperature changes and the correct side panel being lit by the sun as long as the filter converges properly, but not the magnitude of the temperature at a specific time. A solar panel power model is also attempted, which was found to be unusable due to power budget issues and the side panel current sensors railing. Convergence of the three sets of data showed that a 30 second snapshot rate converges to a more accurate attitude information when the satellite has a 0.1 rev/min rotation rate compared to the 1.0 rev/min rotation rate data. A 10 second snapshot rate gives more accurate attitude information for data from a satellite with a 1.0 rev/min rotation rate. By investigating the drastic reduction in the satellite’s rotation rate over 6 months, it was discovered that the satellite’s antenna is most likely magnetized, causing it to try to align itself with the Earth’s magnetic field, slowing down the rotation rate of the satellite from 1 rev/min to 0.1 rev/min

Winter diet, seed preferences and foraging behavior of Henslow\u27s Sparrows (Ammodramus henslowii) in southeastern Louisiana

Henslow\u27s Sparrow (Ammodramus henslowii) is a grassland bird whose population is declining throughout its range, mainly due to habitat loss. The Longleaf Pine forest ecosystems in which Henslow\u27s Sparrows spend their winters are reduced to 5% of their former range. The winter ecology of Henslow\u27s Sparrow remains understudied, especially regarding important aspects of diet and foraging behavior. To determine winter diet, I collected fecal samples from Henslow\u27s Sparrows during banding operations in southeastern Louisiana pine savannas from October 2003-March 2004 and October 2004-April 2005. I then analyzed the samples for presence of seeds and arthropod parts, identified them to the lowest classification possible, and then used both multivariate and univariate techniques to look for variations in diet due to a savannas burn history, month of year and their interaction. I also conducted multiple-offer and simple-offer seed preference experiments on captive Henslow\u27s Sparrows in December 2004 and February 2005 to test a variety of seed types found at differing abundances within the study sites. Commonly consumed seeds included Scleria spp., Rhynchospora spp., the category including Dichanthelium spp. and Panicum spp., and the combined category of Aristida spp., Schizachyrium spp. and Andropogon spp. Frequently consumed arthropods included Arachnids and insects from the orders Coleoptera, Hymenoptera, Hemiptera and Orthoptera. Diets varied significantly among months, most likely due to resource availability and timing of seed senescence. Results of seed preference experiments suggest that Henslow\u27s Sparrows preferred Dichanthelium angustifolium, Muhlenbergia expansa and Eupatorium leucolepis while they avoided Schizachyrium scoparium. Ctenium aromaticum and Panicum anceps appeared to be secondarily preferred food items

Whose turn is it anyway : the impact of job rotation on the reduction of cumulative trauma disorders

In today\u27s fast-paced world, repetitive activity on the job has become very demanding. Many workers are suffering from injuries known as cumulative trauma disorders (CTDs). Job rotation can be an effective and powerful tool when seeking to minimize CTDs by allowing workers to experience different activities, thereby distributing the physical demands on the workers\u27 bodies. A case study was conducted on a northwestern New York manufacturing facility to identify the presence of excessive work stressors and to formulate potential corrective actions, including an analysis of their current job rotation system. The jobs were evaluated using the Rapid Upper Limb Assessment. This study provides valuable information on the benefits of an effective job rotation system, and the steps necessary to implement one. For the case study, a reduction of exposure to work stressors of 20.9% for the Overall Risk Index can be accomplished using the new job rotation system methods

A Preliminary Study of Solar Powered Aircraft and Associated Power Trains

The feasibility of regeneratively powered solar high altitude powered platform (HAPP) remotely piloted vehicles was assessed. Those technologies which must be pursued to make long duration solar HAPPs feasible are recommended. A methodology which involved characterization and parametric analysis of roughly two dozen variables to determine vehicles capable of fulfilling the primary mission are defined. One of these vehicles was then conceptually designed. Variations of each major design parameter were investigated along with state-of-the-art changes in power train component capabilities. The midlatitude mission studied would be attainable by a solar HAPP if fuel cell, electrolyzer and photovoltaic technologies are pursued. Vehicles will be very large and have very lightweight structures in order to attain the combinations of altitude and duration required by the primary mission

Depression, Methamphetamine use, and Alcohol Consumption among Thai Youth in Chiang Mai Province: The Exploration of Perceptions of Depression and Associations between Substance Use and Depressive Symptoms

Background: Methamphetamine use and alcohol consumption have reached epidemic levels among rural Thai adolescents and young adults in Chiang Mai Province, Thailand. High levels of depressive symptoms often occur among individuals who abuse or who are dependent on methamphetamine and alcohol. An understanding of the nature of associations between these substances and depressive symptoms can advance understanding of prevention and treatment options among individuals most at risk. Understanding the nature of depression as perceived by this population and the individual and social correlates can inform culturally-appropriate interventions. Methods: A mixed methods design was implemented and employed the use of a convergent parallel design to understand depressive symptoms and their correlates. Data obtained from a structured survey included information pertaining to lifetime and recent methamphetamine use, alcohol consumption, other illicit drugs, and depressive symptoms and was used for the epidemiological analyses. Primary variables of interest were lifetime and recent methamphetamine use, lifetime and recent alcohol consumption and depressive symptoms. In-depth interviews were conducted among 24 adolescent and young adult participants aged 14 - 24 from January – February 2013. Qualitative research was conducted to explore the perception of depression among Thai youth and potential factors responsible for the onset of depression in this population. Results: Multivariate linear regression revealed statistically significant associations between recent methamphetamine use and CES-D scores. Multivariate logistic regression revealed significant associations between lifetime and recent methamphetamine use and high levels of depressive symptoms. Multivariate linear and logistic regression models did not reveal statistically significant associations between lifetime/recent alcohol consumption and depressive symptoms. Explorations of symptoms of depression as perceived by respondents demonstrated similarities to Western cultures. Social antecedents were specific to the context of rural Chiang Mai. Substance use, abuse, and dependence were viewed as a way to self-medicate depressive symptoms. Conclusions: Methamphetamine use, alcohol consumption, and depressive symptoms are prevalent among Thai adolescents and young adults in Chiang Mai. This research suggests that culturally-relevant and integrated interventions for depression, methamphetamine use, and alcohol consumption are needed in rural Chiang Mai Province

Estimating Canopy Gap Fraction Using ICESat GLAS within Australian Forest Ecosystems

Spaceborne laser altimetry waveform estimates of canopy Gap Fraction (GF) vary withrespect to discrete return airborne equivalents due to their greater sensitivity to reflectance differencesbetween canopy and ground surfaces resulting from differences in footprint size, energy thresholding,noise characteristics and sampling geometry. Applying scaling factors to either the ground or canopyportions of waveforms has successfully circumvented this issue, but not at large scales. This studydevelops a method to scale spaceborne altimeter waveforms by identifying which remotely-sensedvegetation, terrain and environmental attributes are best suited to predicting scaling factors basedon an independent measure of importance. The most important attributes were identified as: soilphosphorus and nitrogen contents, vegetation height, MODIS vegetation continuous fields productand terrain slope. Unscaled and scaled estimates of GF are compared to corresponding ALS datafor all available data and an optimized subset, where the latter produced most encouraging results(R2 = 0.89, RMSE = 0.10). This methodology shows potential for successfully refining estimates ofGF at large scales and identifies the most suitable attributes for deriving appropriate scaling factors.Large-scale active sensor estimates of GF can establish a baseline from which future monitoringinvestigations can be initiated via upcoming Earth Observation missions

Biophysical characterization of protected areas globally through optimized image segmentation and classification

Protected areas (PAs) need to be assessed systematically according to biodiversity values and threats in order to support decision-making processes. For this, PAs can be characterized according to their species, ecosystems and threats, but such information is often difficult to access and usually not comparable across regions. There are currently over 200,000 PAs in the world, and assessing these systematically according to their ecological values remains a huge challenge. However, linking remote sensing with ecological modelling can help to overcome some limitations of conservation studies, such as the sampling bias of biodiversity inventories. The aim of this paper is to introduce eHabitat+, a habitat modelling service supporting the European Commission's Digital Observatory for Protected Areas, and specifically to discuss a component that systematically stratifies PAs into different habitat functional types based on remote sensing data. eHabitat+ uses an optimized procedure of automatic image segmentation based on several environmental variables to identify the main biophysical gradients in each PA. This allows a systematic production of key indicators on PAs that can be compared globally. Results from a few case studies are illustrated to show the benefits and limitations of this open-source tool

Modeling and mapping in support of the Regional conservational Strategy Framework

Prior to November 2010, when The Intertwine Alliance launched the Regional Conservation Strategy (RCS) and Biodiversity Guide (RBG) efforts for the Portland-Vancouver metropolitan region, conservation priorities in the metropolitan region were identified at a broad regional scale that generally excluded urban areas (e.g., state conservation strategies and Willamette Synthesis); were regional but based solely on expert opinion (e.g., Natural Features); and consisted of localized priorities that abruptly ended at jurisdiction boundaries. The goal of the RCS was to fill in the gaps between broad and local scales of information related to conservation priorities. RCS members envisioned a data-driven approach that could add a regional perspective to local efforts and facilitate cross-scale cooperation toward protecting remaining valuable habitat in the Portland-Vancouver metropolitan region. Also, RCS members expected that the product would complement rather than replace local knowledge, by validating what we know and expanding to areas we know less well. In June 2011, INR completed an initial proof-of-concept product describing high value conservation areas in the Portland-Vancouver region. The product demonstrated a methodology that enabled stakeholder involvement while also being data-driven. In September 2012, we completed a second version of this product that is reported on in this document. While the product is considered complete at this time, it is expected and hoped that the models and data will be updated and improved upon into the future as more and better information becomes available so that the product functions as a “living work” rather than a one-time snapshot in time. Several key products resulted from the project: the High Value Habitat data describing high value terrestrial habitat within the metropolitan region, the Riparian Habitat data describing high value habitat adjacent to streams and rivers, and the high spatial resolution land cover data set describing land cover at a 5 m spatial resolution

Indicators for Assessing Habitat Values and Pressures for Protected Areas—An Integrated Habitat and Land Cover Change Approach for the Udzungwa Mountains National Park in Tanzania

Assessing the status and monitoring the trends of land cover dynamics in and around protected areas is of utmost importance for park managers and decision makers. Moreover, to support the Convention on Biological Diversity (CBD)’s Strategic Action Plan including the Aichi Biodiversity Targets, such efforts are necessary to set a framework to reach the agreed national, regional or global targets. The integration of land use/cover change (LULCC) data with information on habitats and population density provides the means to assess potential degradation and disturbance resulting from anthropogenic activities such as agriculture and urban area expansion. This study assesses the LULCC over a 20 year (1990–2000–2010) period using freely available Landsat imagery and a dedicated method and toolbox for the Udzungwa Mountains National Park (UMNP) and its surroundings (20 km buffer) in Tanzania. Habitat data gathered from the Digital Observatory for Protected Areas (DOPA)’s eHabitat+ Web service were used to perform ecological stratification of the study area and to develop similarity maps of the potential presence of comparable habitat types outside the protected area. Finally, integration of the habitat similarity maps with the LULCC data was applied in order to evaluate potential pressures on the different habitats within the national park and on the linking corridors between UMNP and other protected areas in the context of wildlife movement and migration. The results show that the UMNP has not suffered from relevant human activities during the study period. The natural vegetation area has remained stable around 1780 km2. In the surrounding 20 km buffer area and the connecting corridors, however, the anthropogenic impact has been strong. Artificially built up areas increased by 14.24% over the last 20 years and the agriculture area increased from 11% in 1990 to 30% in the year 2010. The habitat functional types and the similarity maps confirmed the importance of the buffer zone and the connecting corridors for wildlife movements, while the similarity maps detected other potential corridors for wildlife

The Prelude to the Deep Minimum between Solar Cycles 23 and 24: Interplanetary Scintillation Signatures in the Inner Heliosphere

Extensive interplanetary scintillation (IPS) observations at 327 MHz obtained between 1983 and 2009 clearly show a steady and significant drop in the turbulence levels in the entire inner heliosphere starting from around ~1995. We believe that this large-scale IPS signature, in the inner heliosphere, coupled with the fact that solar polar fields have also been declining since ~1995, provide a consistent result showing that the buildup to the deepest minimum in 100 years actually began more than a decade earlier.Comment: 9 pages, 4 figures, accepted for publication in Geophysical Research Letters on 28 September 201