Conservation areas in tropical forests protect the most diverse and threatened ecosystems on the planet. In the Amazon, ungulates are important to forest structure and diversity, but are also food for rural people. I estimated occupancy of white-lipped peccary (Tayassu pecari), collared peccary (T. tajacu), lowland tapir (Tapirus terrestris), and red brocket deer (Mazama americana) in Tambopata, Peru to evaluate how different management designations along with anthropogenic and habitat factors influenced the distribution of these species. I used track surveys (n = 258) and camera surveys (n = 256) to estimate ungulate occupancy and detection at 55 sites in a national reserve, a native community, and adjacent buffer areas from May 2008 to March 2009. The best approximating model for white-lipped peccary, lowland tapir, and red brocket deer included only a variable of travel time from the nearest city (a measure of an area's accessibility). Management designation also had some influence on occupancy. I found significantly higher occupancy for collared peccary and red brocket deer in reserve and buffer areas than in the native community but there was no significant difference in occupancy between the reserve and buffer. These results indicate that passive protection might be an adequate management strategy for inaccessible areas of this region. However, as the Amazon continues to be developed, more active enforcement of park boundaries and regulations should be enacted if wildlife conservation is to be effective.

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Many Indigenous communities around the world are facing a health crisis aggravated by environmental degradation and dispossession. Through community-based participatory research, we examined barriers to land use, declining environmental health and human health implications for the Isga People in west-central Alberta, Canada. Through interviews, land use-and-occupancy and traditional and local knowledge of environmental change was spatially documented. Key concerns including declining wildlife health and water quality were largely attributed to the petroleum and forestry industries. Barriers included the encroachment of industry, agriculture and urban development, and a legacy of state-imposed assimilation policies. Human health concerns were associated with these barriers and environmental degradation along with a loss of connection to land and cultural practices. However, community resilience was also evident in the persistence of land use and cultural revival. Underlying environmental and sociopolitical factors are crucial for the health and wellbeing of the Isga and Indigenous Peoples worldwide.

With advances in communications technologies, there is a constant need for higher data rates. One possible solution to overcome this need is to allocate additional bandwidth. However, due to spectrum scarcity this is no longer feasible. In addition, the results of spectrum measurement campaigns discovered the fact that the available spectrum is under-utilized. One of the most significant solutions to solve the under- utilization of radio-frequency (RF) spectrum is the cognitive radio (CR) concept. A valid mathematical model that can be applied for most practical scenarios and also captures the random fluctuations of the spectrum is necessary. This model provides a significant insight and also a better quantitative understanding of such systems and this is the topic of this dissertation. Compact mathematical formulations that describe the realistic spectrum usage would improve the recent theoretical work to a large extent. The data generated for such models, provide a mean for a more realistic evaluation of the performance of CR systems. However, measurement based models require a large amount of data and are subject to measurement errors. They are also likely to be subject to the measurement time, location, and methodology. In the first part of this dissertation, we introduce cognitive radio networks and their role on solving the problem of under-utilized spectrum. In the second part of this dissertation, we target the random variable which accounts for the fraction of available subcarriers for the secondary users in an OFDMA based CR system. The time and location dependency of the traffic is taken into account by a non-homogenous Poisson Point Process (PPP). In the third part, we propose a comprehensive statistical model for user activity, spectrum occupancy, and system throughput in the presence of mutual interference in an OFDMA-based CR network which accounts for the sensing procedure of spectrum sensor, spectrum demand-model and spatial density of primary users, system objective for user satisfaction which is to support as many users as possible, and environment-dependent conditions such as propagation path loss, shadowing, and channel fading. In the last part of this dissertation, unlike the second and the third parts that the modeling is theoretical and based on limiting assumptions, the spectrum usage modeling is based on real data collected from an extensive measurement.

Thesis (M.S.H.A.)--University of Michigan, 1981.

Thesis (M.S.H.A.)--University of Michigan, 1981.

Indiana University-Purdue University Indianapolis (IUPUI) / This thesis discusses occupancy grid map, collision avoidance system and belief theory, and propose some of the latest and the most effective method such as predictive occupancy grid map, risk evaluation model and OGM role in the belief function theory with the approach of decision uncertainty according to the environment perception with the degree of belief in the driving command acceptability. Finally, how the proposed models mitigate or prevent the occurrence of the collision.

Consider n players whose "scores" are independent and identically distributed values {Xi}i=1n from some discrete distribution F. We pay special attention to the cases where (i) F is geometric with parameter p{combining right arrow above}0 and (ii) F is uniform on {1,2,. . . ,N}; the latter case clearly corresponds to the classical occupancy problem. The quantities of interest to us are, first, the U-statistic W which counts the number of "ties" between pairs i, j; second, the univariate statistic Yr, which counts the number of strict r-way ties between contestants, i.e., episodes of the form Xi1=Xi2=. . .=Xir; Xj≠Xi1;j≠i1,i2,. . . ,ir; and, last but not least, the multivariate vector ZAB=(YA, YA+1,. . . ,YB). We provide Poisson approximations for the distributions of W, Yr and ZAB under some general conditions. New results on the joint distribution of cell counts in the occupancy problem are derived as a corollary.

The Southeast Asian island of Borneo boasts an incredible diversity of terrestrial mammals which is threatened by habitat loss. Understanding the abundance and distribution of these species is essential for conservation and management. We assessed the occurrence of terrestrial mammals within two commercial forest reserves in Sabah, Malaysian Borneo. In particular, we investigated the habitat associations of the Sunda stink-badger, whose patchy distribution is not well understood. To improve detection probability and precision of model parameters, we deployed 2 camera-traps at sample stations. Our results showed that Sunda stink-badgers are likely dietary and habitat generalists, that may benefit from forest disturbance. Additionally, we found that unguligrade species were associated with high detection probability when data from one camera trap was considered and inclusion of a second camera further increased the detectability of ungulates compared to all other species. We suggest that future studies consider physical characteristics of focal species to maximize effectiveness of camera effort and ensure that data collection is efficient and meets project needs.

Commercial catfish production is an inveterate industry within the southeastern United States. Bacterial disease is a significant detriment to global aquaculture, including the United States catfish industry. Among them, an atypical strain of the bacterium Aeromonas hydrophila has plagued the industry since the late 2000s. Atypical A. hydrophila (aAh) outbreaks are largely acute, resulting in catastrophic losses. The disease ecology, prevalence, and genetic distribution are poorly understood. Atypical Aeromonas hydrophila displays a rapid onset with few warning signs of the impending disease, making it difficult for early detection. At present there are two recognized haplotypes of aAh. This project aimed to investigate changes in the spatial and temporal distributions of these haplotypes. The analysis of clinical isolates from different geographic regions across multiple years revealed complete supplanting by the younger haplotype in the Mississippi Delta within 5 years of first isolation. Comparative genomics demonstrated distinct divergences in specific virulence components between the two strains, specifically the Type VI Secretion System, which may explain putative differences in outbreak dynamics and recent displacement of one strain by the other. Also, a rapid, non-lethal screening method was validated that can detect aAh within the catfish host. This method affords data collection regarding infection severity prior to onset of disease and, can predict aAh prevalence at the fish- and pond-levels. The occupancy model indicates more than half the population within a pond may be infected with aAh despite no overt signs of disease. Additionally, aAh is commonly present in approximately 10% of the population, providing the first evidence of a carrier state in this disease. Lastly, a compartmental SLIR model was used to investigate disease dynamics of aAh in catfish aquaculture ponds. Simulations suggest the introduction hypothesis does affect estimated pond profit and antibiotic intervention is an economical treatment for aAh. Routine monitoring was less economical and could dramatically reduce profit in some scenarios. Overall, this work expands our current knowledge of aAh in catfish aquaculture and lays the foundation for future studies investigating aAh management and mitigation of bacterial disease in catfish aquaculture.