2,360 research outputs found
Consideration of Interference Correlation Properties in a JD-CDMA Mobile Radio System with Coherent Receiver Antenna Diversity
No full textIn code division multiple access (CDMA) mobile radio systems, both intersymbol interference and multiple access interference arise which can be combatted by using Joint Detection (JD) techniques, to reduce the degradation in performance resulting from time variance, coherent receiver antenna diversity (CRAD) can be used. The application of JD techniques offers the possibility to exploit the knowledge of noise covariances at the receiver. If only intercell (cochannel) interference is considered, the noise covariances in the uplink receiver of a multiple receiver antenna CDMA mobile radio system depend mainly on the directions of arrival (DOAs) of the interfering signals and the receiver antenna placement. Therefore, if the interferer DOAs are known at the base station, these covariances could be estimated. In this thesis, a realistic model of the uplink of a JD CDMA mobile radio system with CRAD is described in which the above mentioned interference cancelling method is used. Simulation results according to this model are given and evaluated.Applied SciencesElectrical EngineeringTelecommunications and Traffic Control Systems Grou
Dairy farmers’ perceptions toward the implementation of on-farm Johne’s disease prevention and control strategies
No full textmplementation of specific management strategies on dairy farms is currently the most effective way to reduce the prevalence of Johne’s disease (JD), an infectious chronic enteritis of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). However, dairy farmers often fail to implement recommended strategies. The objective of this study was to assess perceptions of farmers participating in a JD prevention and control program toward recommended practices, and explore factors that influence whether or not a farmer adopts risk-reducing measures for MAP transmission. Semi-structured interviews were conducted with 25 dairy farmers enrolled in a voluntary JD control program in Alberta, Canada. Principles of classical grounded theory were used for participant selection, interviewing, and data analysis. Additionally, demographic data and MAP infection status were collected and analyzed using quantitative questionnaires and the JD control program database. Farmers’ perceptions were distinguished according to 2 main categories: first, their belief in the importance of JD, and second, their belief in recommended JD prevention and control strategies. Based on these categories, farmers were classified into 4 groups: proactivists, disillusionists, deniers, and unconcerned. The first 2 groups believed in the importance of JD, and proactivists and unconcerned believed in proposed JD prevention and control measures. Groups that regarded JD as important had better knowledge about best strategies to reduce MAP transmission and had more JD risk assessments conducted on their farm. Although not quantified, it also appeared that these groups had more JD prevention and control practices in place. However, often JD was not perceived as a problem in the herd and generally farmers did not regard JD control as a “hot topic” in communications with their herd veterinarian and other farmers. Recommendations regarding how to communicate with farmers and motivate various groups of farmers according to their specific perceptions were provided to optimize adoption of JD prevention and control measures and thereby increase success of voluntary JD control programs
Constitutions of dwelling : ressentlement from Jd. São Marcos to Jd. Real
No full textOrientador: Daniel Joseph HoganDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de GeociênciasResumo: O município de Cubatão (SP) ainda lida com as conseqüências de sua expressiva industrialização. Dentre elas, associado ao conjunto significativo de impactos ambientais, está o problema habitacional: praticamente, metade das famílias do município vive em habitações precárias. Uma das medidas que vêm sendo tomadas, nesta década, para a resolução deste problema é o reassentamento urbano. Em Cubatão, esta política remove a população da área de risco e promove a mudança das famílias para conjuntos habitacionais construídos especificamente para estes moradores; oferecendo moradia fisicamente mais estável, junto a bairros consolidados. O último reassentamento concretizado neste município foi o das famílias do Jd. São Marcos para o Jd. Real. Do ponto de vista dos moradores, o reassentamento implica uma reestruturação da vida, na medida em que muda o espaço em que está a casa. A qualidade desta reestruturação é que responde à eficácia e justiça desta política pública do ponto de vista da população envolvida. Clarificar o devir e os fatores envolvidos deve ajudar na reflexão das conseqüências do reassentamento para os moradores, auxiliando na reflexão e planejamento desta política pública. A reestruturação se dá no cotidiano, nas pequenas ou nas fundamentais atividades que centramos na casa; em outras palavras, o cerne da reestruturação da vida em função do reassentamento está na articulação entre espaço, indivíduo e o modo como habitamos. A partir desta constatação, trazemos o habitar como categoria para apreender as conseqüências do reassentamento. Apoiados nas formulações sobre sentido do habitar de Heidegger, que auxiliam a refletir sobre a articulação entre espaço, indivíduo e morar, discutimos sobre o papel da casa, do bairro, da articulação entre lugares privados e públicos e da apropriação do espaço como fenômenos que compõe o habitar e que entram em xeque frente ao reassentamentoAbstract: The City of Cubatão (SP) still deals with the consequences of its expressive industrialization. Among them, associated with a set of significant environmental impacts, is the habitation problem: almost half of the families in the city live in precarious residences. The urban resettlement is one of the measures that are being taken in this decade to solve this problem. In Cubatão, this policy removes the population in risk areas and promotes the displacement of the families to habitation sets constructed specifically for these residents; providing housing physically more stable, within consolidated neighborhood. The last resettlement achieved in this city involved the families of Jd. São Marcos to Jd. Real. From the residents' perspective, the resettlement implies restructuring of life, in as much as it changes the space of the house. The quality of this restructuring direct responds to the efficiency and justice of this public policy from the residents' perspective subjected to this. Clarify the destiny and the factors involved should help in the reflection of resettlements' consequences to residents, helping the studies and planning of such public policy. The restructuring happens in daily life, in small or fundamental activities that we concentrate in the house; in other words, the heart of the restructuring of life in the light of resettlement is in the articulation between space, individual and the way that we live. From this observation, we bring 'dwelling' as a category to embrace the consequences of resettlement. Supported in formulations on "dwelling" discussed by Heidegger and his aid to reflect the articulation between space, individual and settlement we discuss the role of home, neighborhood, articulation between private and public places and space appropriation as phenomena that compose the dwelling and confront the resettlement focusMestradoAnálise Ambiental e Dinâmica TerritorialMestre em Geografi
Knowledge gaps that hamper prevention and control of Mycobacterium avium subspecies paratuberculosis infection
No full textIn the last decades, many regional and country‐wide control programmes for Johne's disease (JD ) were developed due to associated economic losses, or because of a possible association with Crohn's disease. These control programmes were often not successful, partly because management protocols were not followed, including the introduction of infected replacement cattle, because tests to identify infected animals were unreliable, and uptake by farmers was not high enough because of a perceived low return on investment. In the absence of a cure or effective commercial vaccines, control of JD is currently primarily based on herd management strategies to avoid infection of cattle and restrict within‐farm and farm‐to‐farm transmission. Although JD control programmes have been implemented in most developed countries, lessons learned from JD prevention and control programmes are underreported. Also, JD control programmes are typically evaluated in a limited number of herds and the duration of the study is less than 5 year, making it difficult to adequately assess the efficacy of control programmes. In this manuscript, we identify the most important gaps in knowledge hampering JD prevention and control programmes, including vaccination and diagnostics. Secondly, we discuss directions that research should take to address those knowledge gaps
Evaluation of an alternative method of herd classification for infection with paratuberculosis in cattle herds in the United States
No full textObjective - To develop a better system for classification of herd infection status for paratuberculosis (Johne's disease JD]) in US cattle herds on the basis of the risk of potential transmission of Mycobacterium avium subsp paratubeculosis. Sample - Simulated data for herd size and within-herd prevalence; sensitivity and specificity for test methods obtained from consensus-based estimates. Procedures - Interrelationships among variables influencing interpretation and classification of herd infection status for JD were evaluated by use of simulated data for various herd sizes, true within-herd prevalences, and sampling and testing methods. The probability of finding ≥1 infected animal in herds was estimated for various testing methods and sample sizes by use of hypergeometric random sampling. Results - 2 main components were required for the new herd JD classification system: the probability of detection of infection determined on the basis of test results from a sample of animals and the maximum detected number of animals with positive test results. Tables were constructed of the estimated probability of detection of infection, and the maximum number of cattle with positive test results or fecal pools with positive culture results with 95% confidence for classification of herd JD infection status were plotted. Herd risk for JD was categorized on the basis of 95% confidence that the true within-herd prevalence was ≤15%, ≤10%, ≤5%, or ≤2%. Conclusions and Clinical Relevance - Analysis of the findings indicated that a scientifically rigorous and transparent herd classification system for JD in cattle is feasible.Source type: Electronic(1
Factors associated with participation of Alberta dairy farmers in a voluntary, management-based Johne’s disease control program
No full textThe Alberta Johne's Disease Initiative (AJDI) is a voluntary, management-based prevention and control program for Johne's disease (JD), a wasting disease in ruminants that causes substantial economic losses to the cattle industry. Despite extensive communication about the program's benefits and low cost to participating producers, approximately 35% of Alberta dairy farmers have not enrolled in the AJDI. Therefore, the objective was to identify differences between AJDI nonparticipants and participants that may influence enrollment. Standardized questionnaires were conducted in person on 163 farms not participating and 61 farms participating in the AJDI. Data collected included demographic characteristics, internal factors (e.g., attitudes and beliefs of the farmer toward JD and the AJDI), external factors (e.g., farmers' JD knowledge and on-farm goals and constraints), as well as farmers' use and influence of various information sources. Nonparticipants and participants differed in at least some aspects of all studied categories. Based on logistic regression, participating farms had larger herds, higher self-assessed knowledge of JD, better understanding of AJDI details before participation, and used their veterinarian more often to get information about new management practices and technologies when compared with nonparticipants. In contrast, nonparticipants indicated that time was a major on-farm constraint and that participation in the AJDI would take too much time. They also indicated that they preferred to wait and see how the program worked on other farms before they participated
FIG. 5 in Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America
No full textFIG. 5. — Premaxillae of Albanerpeton nexuosus Estes, 1981, Campanian and Maastrichtian (Aquilan to Lancian in age), North American Western Interior; A-C, UALVP 16206, fused and nearly complete premaxillae; A, labial view; B, lingual view; C, occlusal view; D, E, UALVP 39955, nearly complete left premaxilla; D, lingual view; E, lateral and slightly dorsal view; F, UALVP 39971, fused premaxillae missing most of right side, occlusal view; G, UALVP 39960, left premaxilla, occlusal view; H, UALVP 39969, left premaxilla broken transversely across pars dorsalis, dorsal view showing dorsal openings of palatal and unnamed foramina in floor of suprapalatal pit; I, OMNH 25345, incomplete left premaxilla, labial view; J, OMNH 60238, incomplete left premaxilla, lingual and slightly ventral view; K, UCM 38713, incomplete left premaxilla, lingual view. Provenances: A-H, UALVP specimens, Milk River Formation, lower Campanian (i.e. Aquilan in age), Alberta; I, J, OMNH specimens, Aguja Formation, middle Campanian (i.e. Judithian in age), Texas; K, UCM specimen, Laramie Formation, upper Maastrichtian (i.e. Lancian in age), Colorado. Arrows: 1, palatal foramen; 2, unnamed foramen in junction between pars palatinum and pars dentalis. Scale bar: 1 mm.Published as part of Gardner, JD, 2000, Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America, pp. 349-388 in Geodiversitas 22 (3) on page 358, DOI: 10.5281/zenodo.537870
FIG. 2 in Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America
No full textFIG. 2. — Dentaries of Albanerpeton nexuosus Estes, 1981 and A. galaktion Fox & Naylor, 1982, Campanian and Maastrichtian (Aquilan to Lancian in age), North American Western Interior; A-I, A. nexuosus; A, B, UCMP 49540, topotypic right mandible consisting of incomplete dentary and anterior tip of angular, A, lingual view, B, occlusal view; C, UCMP 49535, incomplete topotypic right dentary, lingual view; D, E, UCM 38714, incomplete left dentary, D, labial view, E, lingual view; F, RTMP 96.78.152, anterior part of left dentary, lingual view; G, UALVP 16238, anterior part of right dentary, labial view; H, UALVP 40014, anterior part of right dentary, labial view; I, UALVP 40032, posterior part of left dentary missing posteriormost end of area for attachment of postdentary bones, lingual view; J-M, A. galaktion; J, UALVP 16221, incomplete small, left dentary, lingual view; K-M, UALVP 16217, incomplete large, right dentary, K, labial view, L, lingual view, M, occlusal view. Provenances: A-C, UCMP specimens, Lance Formation, Wyoming; D, E, UCM specimen, Laramie Formation, Colorado, all upper Maastrichtian (i.e. Lancian in age); F, RTMP specimen, Oldman Formation, middle Campanian (i.e. Judithian in age), Alberta; G-M, UALVP specimens, Milk River Formation, lower Campanian (i.e. Aquilan in age), Alberta. Scale bars: 1 mm.Published as part of Gardner, JD, 2000, Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America, pp. 349-388 in Geodiversitas 22 (3) on page 355, DOI: 10.5281/zenodo.537870
FIG. 6 in Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America
No full textFIG. 6. — Frontals of Albanerpeton nexuosus Estes, 1982 and A. galaktion Fox & Naylor, 1981, lower Campanian (Aquilan in age), Alberta; A-E, A. nexuosus; A, B, UALVP 39996, fused frontals lacking anterior and posterior ends, A, dorsal view, B, ventral view; C, UALVP 39983, anterior part of fused frontals, dorsal view; D, UALVP 39989, posterior part of left frontal, ventral view; E, UALVP 39987, fragmentary fused frontals, ventral view; F-K, A. galaktion; F, G, UALVP 16216, fused and incomplete frontals missing anteri- or end of bone and posterior end of both ventrolateral crests, F, dorsal view, G, ventral view; H, UALVP 39946, anterior part of fused frontals, dorsal view; I, J, UALVP 39945, posterior one-half of fused frontals missing posterior end of both ventrolateral crests, I, dorsal view, J, ventral view; K, UALVP 39951, right posterior part of fused frontals, ventral view. All specimens are from the Milk River Formation. Scale bars: 1 mm.Published as part of Gardner, JD, 2000, Albanerpetontid Amphibians from the Upper Cretaceous (Campanian and Maastrichtian) of North America, pp. 349-388 in Geodiversitas 22 (3) on page 362, DOI: 10.5281/zenodo.537870
Deadly meals: The influence of personal and job factors on burnout and risky riding behaviours of food delivery motorcyclists
No full textFood delivery riders are overrepresented in road crashes. Arguably, the increased risk experienced by food delivery riders is linked to the working conditions offered by the “gig economy”. Research is needed to fully understand the safety-related issues this vulnerable group of road users face daily and identify opportunities for counter measures. In this investigation, we proposed a new theoretical model to explain the risky behaviour of food delivery motorcyclists based on the well-established Job Demands-Resources (JD-R) model. Following the JD-R, we considered the impact of job demands (job aspects that require sustained effort) and job resources (job aspects that help achieve work-related goals, reduce job demands and stimulate personal development) on the risky riding behaviours of food delivery motorcyclists. The JD-R model was also extended with three constructs, including personal demands, personal resources, and perceived safety risk to explore the role of individuals' within-person aspects. The developed model was tested using data collected from 554 food delivery riders in the two biggest cities in Vietnam. The results showed that job burnout, job resources, and personal demands directly impact risky riding behaviours, in which job burnout was the most significant predictor. Constructs such as job demands, personal resources, and perceived safety risk were not significant predictors of risky riding behaviours. This research shows that organisation-level factors could be modified to prevent risky riding behaviour. The gig economy industry can do much more to improve the safety of delivery riders.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Safety and Security Scienc
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