1,875 research outputs found

    Categorizing Network Attacks Using Pattern Classification Algorithms

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    The United States Air Force relies heavily on computer networks for many day-to-day activities. Many of these networks are affected by various types of attacks that can be launched from anywhere on the globe. The rising prominence of organizations such as the AFCERT and the MAJCOM NOSCs is evidence of an increasing realization among the Air Force leadership that protecting our computer networks is vitally important. A critical requirement for protecting our networks is the ability to detect attacks and intrusion attempts. This research is an effort to refine a portion of an AFIT-developed intrusion detection system known as the COmputer Defense Immune System (CDIS). CDIS is based on the human immune system and uses antibodies to attempt to detect network intrusion attempts. The antibodies have various attributes of which a subset is randomly activated at generation time. This research attempts to determine which of the antibody attributes are most useful in helping to build successful antibodies

    Image Annotation and Topic Extraction Using Super-Word Latent Dirichlet

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    This research presents a multi-domain solution that uses text and images to iteratively improve automated information extraction. Stage I uses local text surrounding an embedded image to provide clues that help rank-order possible image annotations. These annotations are forwarded to Stage II, where the image annotations from Stage I are used as highly-relevant super-words to improve extraction of topics. The model probabilities from the super-words in Stage II are forwarded to Stage III where they are used to refine the automated image annotation developed in Stage I. All stages demonstrate improvement over existing equivalent algorithms in the literature

    Context-Driven Image Annotation Using ImageNet

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    Image annotation research has demonstrated success on test data for focused domains. Unfortunately, extending these techniques to the broader topics found in real world data often results in poor performance. This paper proposes a novel approach that leverages WordNet and ImageNet capabilities to annotate images based on local text and image features. Signatures generated from ImageNet images based on WordNet synonymous sets are compared using Earth Mover\u27s Distance against the query image and used to rank order surrounding words by relevancy. The results demonstrate effective image annotation, producing higher accuracy and improved specificity over the ALIPR image annotation system. Abstract © AAAI

    Applicability of Latent Dirichlet Allocation to Multi-Disk Search

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    Digital forensics practitioners face a continual increase in the volume of data they must analyze, which exacerbates the problem of finding relevant information in a noisy domain. Current technologies make use of keyword based search to isolate relevant documents and minimize false positives with respect to investigative goals. Unfortunately, selecting appropriate keywords is a complex and challenging task. Latent Dirichlet Allocation (LDA) offers a possible way to relax keyword selection by returning topically similar documents. This research compares regular expression search techniques and LDA using the Real Data Corpus (RDC). The RDC, a set of over 2400 disks from real users, is first analyzed to craft effective tests. Three tests are executed with the results indicating that, while LDA search should not be used as a replacement to regular expression search, it does offer benefits. First, it is able to locate documents when few, if any, of the keywords exist within them. Second, it improves data browsing and deals with keyword ambiguity by segmenting the documents into topics

    Caribou distribution during calving in the northeast National Petroleum Reserve-Alaska, June 1998 to 2000

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    Barren ground caribou (Rangifer tarandus granti) of the Teshekpuk Caribou Herd (TCH) inhabit the western portion of Alaska's Arctic Coastal Plain within the National Petroleum Reserve—Alaska (NPR-A). Alaska's North Slope communities, management agencies, and private industry are interested in this herd because of its importance as a subsistence resource and location relative to potential petroleum development. From 1998 through 2000, we monitored caribou distribution during the calving period within the Northeast Planning Area of the NPR-A using systematic strip-transect aerial surveys, as well as VHF and satellite telemetry for cow caribou. Aerial survey and telemetry data indicated cows with calves were distributed around Teshekpuk Lake, with a concentration south of the lake in 1999 and 2000. Inconsistencies in weather conditions, survey timing (both strip-transect and VHF surveys), 100% coverage survey areas, and small sample sizes confound interpretations of our results. However, several patterns were apparent. Later transect survey timing (7—12 June versus 4—7 and 5—8 June) resulted in more cow/calf pairs recorded. Our 18% coverage area, originally based on VHF telemetry data for the extent of TCH calving, covered a consistently high proportion (95% to 100%) of the annual calving ranges (95% kernel utilization distributions), but accounted for only 24% to 46% of the adult cows in the TCH based on the current Alaska Department of Fish and Game population estimate (1999) and average 1998¬2000 herd composition. It appears that either our transect survey methodology significantly underestimated the true number of caribou cows in the study area, many cows calved outside the area or moved into the area and calved after our surveys, or we have over estimated the number of reproductive cows in the herd. Our 100% coverage transect areas covering oil and gas lease areas, contained 38% of the calving range with 23% of TCH cows in 1999; and 18% of the calv¬ing range with 8% of TCH cows in 2000. Based on 95% minimum convex polygon ranges, satellite collared cow/calf pairs were not stationary during either our survey period (14.7 ± 6.56 km2; mean ± standard error of the mean; 4—12 June) or during the calving period (86.9 ± 72.30 km2; 1—20 June) during 1998—2000. Site specific pre-development data on caribou distribution during calving in NPR-A will be useful for assessing the importance of specific areas to caribou during calving and for designing oilfields that minimize impacts should oil development occur

    Effects of nitrogen and potassium fertilization on the susceptibility of tomatoes to post-harvest proliferation of Salmonella enterica

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    Fresh fruits and vegetables are increasingly recognized as vehicles of salmonellosis. Pre- and post-harvest environmental conditions, and physiological, and genetic factors are thought to contribute to the ability of human pathogens to persist in the production environment, attach to, colonize and proliferate in and on raw produce. How field production conditions affect the post-harvest food safety outcomes is not entirely understood. This study tested how varying nitrogen and potassium fertilization levels affected the "susceptibility" of tomatoes to Salmonella infections following the harvest of fruits. Two tomato varieties grown over three seasons under high, medium, and low levels of nitrogen and potassium fertilization in two locations were inoculated with seven strains of Salmonella. Even though the main effects of nitrogen and potassium fertilization on the susceptibility of tomatoes to infections with Salmonella enterica were not statistically significant overall, differences in nitrogen concentrations in plant tissues correlated with the susceptibility of partially ripe tomatoes (cv. Solar Fire) to Salmonella. Tomato maturity and the season in which tomatoes were produced had the strongest effect on the ability of Salmonella to multiply in tomatoes. Tomato phenolics, accumulation of which is known to correlate with rates of the N fertilization, did not inhibit growth of Salmonella in vitro

    Caribou Distribution During the Post-calving Period in Relation to Infrastructure in the Prudhoe Bay Oil Field, Alaska

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    There is concern that caribou (Rangifer tarandus) may avoid roads and facilities (i.e. infrastructure) in the Prudhoe Bay oil field (PBOF) in northern Alaska, and that this avoidance can have negative effects on the animals. We quantified the relationship between caribou distribution and PBOF infrastructure during the post-calving period (mid-June to mid-August) with aerial surveys from 1990 to 1995. We conducted four to eight surveys per year with complete coverage of the PBOF. We identified active oil field infrastructure and used a geographic information system (GIS) to construct ten 1 km wide concentric intervals surrounding the infrastructure. We tested whether caribou distribution is related to distance from infrastructure with a chi-squared habitat utilization-availability analysis and log-linear regression. We considered bull, calves, and total caribou of all sex/age classes separately. The habitat utilization-availability analysis indicated there was no consistent trend of attraction to or avoidance of infrastructure. Caribou frequently were more abundant than expected in the intervals close to infrastructure, and this trend was more pronounced for bulls and for total caribou of all sex/age classes than for calves. Log-linear regression (with Poisson error structure) of numbers of caribou and distance from infrastructure were also done, with and without combining data into the 1 km distance intervals. The analysis without intervals revealed no relationship between caribou distribution and distance from oil field infrastructure, or between caribou distribution and Julian date, year, or distance from the Beaufort Sea coast. The log-linear regression with caribou combined into distance intervals showed the density of bulls and total caribou of all sex/age classes declined with distance from infrastructure. Our results indicate that during the post-calving period: 1) caribou distribution is largely unrelated to distance from infrastructure; 2) caribou regularly use habitats in the PBOF; 3) caribou often occur close to infrastructure; and 4) caribou do not appear to avoid oil field infrastructure.On s'inquiète du fait que le caribou (Rangifer tarandus) pourrait éviter les routes et installations (c-à-d. les infrastructures) du champ pétrolifère de Prudhoe Bay dans l'Alaska septentrional et que ce comportement pourrait avoir des répercussions négatives sur les animaux. Des relevés aériens effectués de 1990 à 1995 ont permis de quantifier le rapport entre la distribution du caribou et les infrastructures du champ pétrolifère de Prudhoe Bay au cours de la période suivant immédiatement la mise bas (de mi-juin à mi-août). On a procédé à un nombre de relevés annuels allant de quatre à huit, couvrant toute la superficie du champ. On a identifié les infrastructures du champ pétrolifère qui étaient en activité et utilisé un système d'information géographique (SIG) pour construire dix anneaux concentriques de 1 km de large entourant chaque infrastructure. On a testé l'hypothèse que la distribution du caribou est indépendante de l'éloignement de l'infrastructure grâce au test de chi carré entre l'utilisation et la disponibilité de l'habitat, et à la régression log-linéaire. On a tenu compte séparément de la catégorie des mâles, de celle des veaux et de celle de la population totale, sexe et âge confondus. L'analyse de l'utilisation et de la disponibilité de l'habitat révélait qu'il n'y avait pas de schéma cohérent d'attrait ou d'évitement des infrastructures. Les caribous étaient souvent plus abondants que prévu dans les anneaux proches des infrastructures, et cette tendance était plus prononcée pour les mâles adultes et pour l'ensemble des catégories, sexe et âge confondus, que pour les veaux. On a fait les analyses par régression log-linéaire en regroupant et sans regrouper les données anneaux de 1 km de largeur. L'analyse sans regroupement montrait qu'il n'existe pas de rapport entre la distribution du caribou et l'éloignement des infrastructures du champ pétrolifère, ou entre la distribution du caribou et la date julienne ou même l'éloignement de la côte de la mer de Beaufort. L'analyse log-linéaire avec les caribous regroupés dans des anneaux concentriques montrait que la densité des mâles adultes de l'ensemble de la population, sexe et âge confondus, était plus élevée dans les anneaux jouxtant les infrastructures. Nos résultats indiquent que, durant la période suivant immédiatement la mise bas: (1) la distribution du caribou est dans une large mesure indépendante de l'éloignement des infrastructures; (2) le caribou utilise les habitats au sein du champ pétrolifère de Prudhoe Bay sur une base régulière; (3) le caribou se trouve fréquemment près des infrastructures; et (4) le caribou ne semble pas chercher à éviter les infrastructures du champ pétrolifère

    Sexual behavior, psychosocial and knowledge differences between consistent, inconsistent and non-users of condoms: a study of female bar and hotel workers in Moshi, Tanzania.

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    Understanding psychosocial, sexual behavior and knowledge differences between never, inconsistent and consistent condom users can improve interventions to increase condom use in resource-poor countries, but they have not been adequately studied. We examined these differences in a cohort of 961 female hotel and bar workers in Moshi, Tanzania. Forty-nine percent of women reported no condom use; 39% reported inconsistent use, and 12% reported consistent use. Women with multiple sexual partners in the past five years were less likely to be consistent rather than inconsistent users as were women who had ever exchanged sex for gifts or money. Inconsistent users had higher condom knowledge and higher perceived acceptability of condom use than did never users, but they did not differ from consistent users by these factors. There are important differences between women by level of condom use. These findings can help inform interventions to increase condom use

    Pelvic Trauma: Wses Classification And Guidelines

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    Complex pelvic injuries are among the most dangerous and deadly trauma related lesions. Different classification systems exist, some are based on the mechanism of injury, some on anatomic patterns and some are focusing on the resulting instability requiring operative fixation. The optimal treatment strategy, however, should keep into consideration the hemodynamic status, the anatomic impairment of pelvic ring function and the associated injuries. The management of pelvic trauma patients aims definitively to restore the homeostasis and the normal physiopathology associated to the mechanical stability of the pelvic ring. Thus the management of pelvic trauma must be multidisciplinary and should be ultimately based on the physiology of the patient and the anatomy of the injury. This paper presents the World Society of Emergency Surgery (WSES) classification of pelvic trauma and the management Guidelines.1
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