847 resultados para reserve requirements


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The forthcoming NIST’s Advanced Hash Standard (AHS) competition to select SHA-3 hash function requires that each candidate hash function submission must have at least one construction to support FIPS 198 HMAC application. As part of its evaluation, NIST is aiming to select either a candidate hash function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card implementations of some of the recently proposed MAC alternatives to NMAC (a fully analyzed variant of HMAC) and HMAC algorithms and NMAC/HMAC versions of some recently proposed hash and compression function modes. We show that the recently proposed BNMAC and KMDP MAC schemes are even weaker than NMAC/HMAC against the DPA attacks, whereas multi-lane NMAC, EMD MAC and the keyed wide-pipe hash have similar security to NMAC against the DPA attacks. Our DPA attacks do not work on the NMAC setting of MDC-2, Grindahl and MAME compression functions.

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By definition, regulatory rules (in legal context called norms) intend to achieve specific behaviour from business processes, and might be relevant to the whole or part of a business process. They can impose conditions on different aspects of process models, e.g., control-flow, data and resources etc. Based on the rules sets, norms can be classified into various classes and sub-classes according to their effects. This paper presents an abstract framework consisting of a list of norms and a generic compliance checking approach on the idea of (possible) execution of processes. The proposed framework is independent of any existing formalism, and provides a conceptually rich and exhaustive ontology and semantics of norms needed for business process compliance checking. The possible uses of the proposed framework include to compare different compliance management frameworks (CMFs).

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The rise in popularity of the digital library has lead to studies addressing digital library education and curricula development to emanate from the United States and Europe. However, to date very little research has been conducted with an Australian focus. Additionally, very few studies worldwide have sought the opinions of practitioners and the influence that these opinions may have on developing appropriate digital library curricula. The current paper is drawn from a larger study which sought to determine the skills and knowledge required of library and information professionals to work in a digital library environment. Data were collected via an online questionnaire from two target groups: practitioners working in academic libraries and Library and Information Science (LIS) educators across Australia. This paper examines in depth the findings from the survey specifically relating to the following topics. Firstly, whether or not there is a need for an educational programme to be targeted solely at the digital library environment. Secondly, the preferred delivery options for such a programme, and preferred models of digital library education. In addition, a determination on the elements which should be included in the curricula of a digital library education programme are discussed. Findings are compared and discussed with reference to the literature which informed the study. Finally, implications for the sustainability of library education programmes in Australia are identified and directions for further research highlighted.

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CoMFA and CoMSIA analysis were utilized in this investigation to define the important interacting regions in paclitaxel/tubulin binding site and to develop selective paclitaxel-like active compounds. The starting geometry of paclitaxel analogs was taken from the crystal structure of docetaxel. A total of 28 derivatives of paclitaxel were divided into two groups—a training set comprising of 19 compounds and a test set comprising of nine compounds. They were constructed and geometrically optimized using SYBYL v6.6. CoMFA studies provided a good predictability (q2 = 0.699, r2 = 0.991, PC = 6, S.E.E. = 0.343 and F = 185.910). They showed the steric and electrostatic properties as the major interacting forces whilst the lipophilic property contribution was a minor factor for recognition forces of the binding site. These results were in agreement with the experimental data of the binding activities of these compounds. Five fields in CoMSIA analysis (steric, electrostatic, hydrophobic, hydrogen-bond acceptor and donor properties) were considered contributors in the ligand–receptor interactions. The results obtained from the CoMSIA studies were: q2 = 0.535, r2 = 0.983, PC = 5, S.E.E. = 0.452 and F = 127.884. The data obtained from both CoMFA and CoMSIA studies were interpreted with respect to the paclitaxel/tubulin binding site. This intuitively suggested where the most significant anchoring points for binding affinity are located. This information could be used for the development of new compounds having paclitaxel-like activity with new chemical entities to overcome the existing pharmaceutical barriers and the economical problem associated with the synthesis of the paclitaxel analogs. These will boost the wide use of this useful class of compounds, i.e. in brain tumors as the most of the present active compounds have poor blood–brain barrier crossing ratios and also, various tubulin isotypes has shown resistance to taxanes and other antimitotic agents.

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This paper analyzes the limitations upon the amount of in- domain (NIST SREs) data required for training a probabilistic linear discriminant analysis (PLDA) speaker verification system based on out-domain (Switchboard) total variability subspaces. By limiting the number of speakers, the number of sessions per speaker and the length of active speech per session available in the target domain for PLDA training, we investigated the relative effect of these three parameters on PLDA speaker verification performance in the NIST 2008 and NIST 2010 speaker recognition evaluation datasets. Experimental results indicate that while these parameters depend highly on each other, to beat out-domain PLDA training, more than 10 seconds of active speech should be available for at least 4 sessions/speaker for a minimum of 800 speakers. If further data is available, considerable improvement can be made over solely out-domain PLDA training.

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Aim: To estimate the colonoscopy burden of introducing population screening for colorectal cancer in New Zealand. Methods: Screening for colorectal cancer using biennial immunochemical faecal occult blood tests offered to people aged 50-74 years of age was modelled using population estimates from Statistics New Zealand for 2011-2031. Modelling to determine colonoscopy requirements was based on participation and test positivity rates from published results of screening programmes. Estimates of the number of procedures required for ongoing adenoma surveillance were calculated using screening literature results of adenoma yield, and New Zealand Guidelines for Adenoma Surveillance. Sensitivity analysis was undertaken on key parameters. Results: For a test positivity of 6.4%, biennial screening using immunochemical faecal occult blood testing with a 60% participation rate, would require 18,000 colonoscopies nationally, increasing to 28,000 by 2031. The majority of procedures are direct referrals from a positive FOBT, with surveillance colonoscopy numbers building over time. Conclusion: Colonoscopy requirements for immunochemical faecal occult blood based population screening for colorectal cancer are high. Significant expansion of services is required and careful management of surveillance procedures to ensure timely delivery of initial colonoscopies whilst maintaining symptomatic services. A model re-run informed by data from the screening pilot will allow improved estimates for the New Zealand setting.

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Organ-specific immunity is a feature of many infectious diseases, including visceral leishmaniasis caused by Leishmania donovani. Experimental visceral leishmaniasis in genetically susceptible mice is characterized by an acute, resolving infection in the liver and chronic infection in the spleen. CD4+ T cell responses are critical for the establishment and maintenance of hepatic immunity in this disease model, but their role in chronically infected spleens remains unclear. In this study, we show that dendritic cells are critical for CD4+ T cell activation and expansion in all tissue sites examined. We found that FTY720-mediated blockade of T cell trafficking early in infection prevented Ag-specific CD4+ T cells from appearing in lymph nodes, but not the spleen and liver, suggesting that early CD4+ T cell priming does not occur in liver-draining lymph nodes. Extended treatment with FTY720 over the first month of infection increased parasite burdens, although this associated with blockade of lymphocyte egress from secondary lymphoid tissue, as well as with more generalized splenic lymphopenia. Importantly, we demonstrate that CD4+ T cells are required for the establishment and maintenance of antiparasitic immunity in the liver, as well as for immune surveillance and suppression of parasite outgrowth in chronically infected spleens. Finally, although early CD4+ T cell priming appeared to occur most effectively in the spleen, we unexpectedly revealed that protective CD4+ T cell-mediated hepatic immunity could be generated in the complete absence of all secondary lymphoid tissues.

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This paper presents three methodologies for determining optimum locations and magnitudes of reactive power compensation in power distribution systems. Method I and Method II are suitable for complex distribution systems with a combination of both radial and ring-main feeders and having different voltage levels. Method III is suitable for low-tension single voltage level radial feeders. Method I is based on an iterative scheme with successive powerflow analyses, with formulation and solution of the optimization problem using linear programming. Method II and Method III are essentially based on the steady state performance of distribution systems. These methods are simple to implement and yield satisfactory results comparable with the results of Method I. The proposed methods have been applied to a few distribution systems, and results obtained for two typical systems are presented for illustration purposes.

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This thesis discusses the contemporary construction of the lived worlds of indigenous Amazonian youths. Today’s native peoples are considerably affected by the processes of globalization and urbanization, which have led to new ways of relating to their cultural traditions. This work presents a case study of Manchineri youngsters aged between 14 and 24 years old living in Acre state in Brazilian Amazonia. The Arawak-speaking Manchineri number some 1,000 people; their legally demarcated reserve is situated next to the River Yaco. The research is based on ethnographic material collected in the Mamoadate reserve and in the state capital, Rio Branco. By comparing the youth in different physical and social environments (the reserve and the city), my attempt has been to search for the most typical elements maintained, altered and created in the current lived worlds of Manchineri youths. Fieldwork methods included interviews, participant observation, photographs, video recordings, and drawings. The material was analyzed within the multidisciplinary framework of the social and cultural construction of knowledge. The study applies the concepts of social field, symbolic capital, and habitus as they have been used by Pierre Bourdieu; perspective as developed recently in Amazonian ethnology; the sacred as a cultural category as understood in the study of religion; and individual and person as concepts central to anthropology and sociology. Additionally, the study can be contextualized within youth studies, Latin American studies, and urban studies. The results of the study show that the everyday lives of young Amazonian native people are formed by a complex mixture of ‘modernity’ and ‘tradition’, fragmentation, and transitions between different conceptual frameworks. Part II discusses the ethnographic material in depth and shows that indigenous adolescents act from a variety of social perspectives: the native youth’s own ethnic group, divided into sub-groups, especially into urban residents and those living in the reserve; ancestors, super-human agents and spirits; other indigenous groups and non-natives. Consequently, besides the traditional initiation ritual, we find various contemporary rites of passage to adulthood: state-education, learning traditional practices, shamanism, matrimony, and transitions between the reserve and urban areas. According to these results, new social roles, political organization, responsibilities, and in general the desire to be respected, require both ‘modern’ and ‘traditional’ abilities. In Part III, the study shows that the current power relations constituted by new social contacts, ethnic recognition, and cooperation with different institutions have resulted in the formation of new social fields: youth cultures, the ethnic group, shamanic practices, the ethnopolitical movement, and indigenous students. The capacity of young Amazonian Indians to act in contemporary social fields produces them as full persons. The study also argues that the elements of the lived worlds can be divided into these social fields. When focusing on these fields, it became evident that these comprise the strategies adopted by young Indians to break through social and cultural barriers.

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BACKGROUND The visual demands of modern classrooms are poorly understood yet are relevant in determining the levels of visual function required to perform optimally within this environment. METHODS Thirty-three Year 5 and 6 classrooms from eight south-east Queensland schools were included. Classroom activities undertaken during a full school day (9 am to 3 pm) were observed and a range of measurements recorded, including classroom environment (physical dimensions, illumination levels), text size and contrast of learning materials, habitual working distances (distance and estimated for near) and time spent performing various classroom tasks. These measures were used to calculate demand-related minimum criteria for distance and near visual acuity, contrast and sustained use of accommodation and vergence. RESULTS The visual acuity demands for distance and near were 0.33 ± 0.13 and 0.72 ± 0.09 logMAR, respectively (using habitual viewing distances and smallest target sizes) or 0.33 ± 0.09 logMAR assuming a 2.5 times acuity reserve for sustained near tasks. The mean contrast levels of learning materials at distance and near were greater than 70 per cent. Near tasks (47 per cent) dominated the academic tasks performed in the classroom followed by distance (29 per cent), distance to near (15 per cent) and computer-based (nine per cent). On average, children engaged in continuous near fixation for 23 ± 5 minutes at a time and during distance-near tasks performed fixation changes 10 ± 1 times per minute. The mean estimated habitual near working distance was 23 ± 1 cm (4.38 ± 0.24 D accommodative demand) and the vergence demand was 0.86 ± 0.07Δ at distance and 21.94 ± 1.09Δ at near assuming an average pupillary distance of 56 mm. CONCLUSIONS Relatively high levels of visual acuity, contrast demand and sustained accommodative-convergence responses are required to meet the requirements of modern classroom environments. These findings provide an evidence base to inform prescribing guidelines and develop paediatric vision screening protocols and referral criteria.

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Space allowance is a major factor influencing animal welfare. For livestock, at least, it plays a critical role in profitability, yet there is little information on the amount of space that animals require. The amount of space an animal occupies as a consequence of its shape and size can be estimated using allometry; linear dimensions (L) can be expressed as L = kW1/3 and surface area (S) as S = kW2/3, where k = a constant and W = the weight of the animal. Such equations have been used to determine the amount of space needed by standing (area [m2] = 0.019W0.66) and lying (area [m2] = 0.027W0.67) animals. Limited studies on the lying down and standing up behaviors of pigs and cattle suggest that the amount of space required can be estimated by area (m2) = 0.047W0.66. Linear space required per animal for behaviors such as feeding or drinking from a trough can be estimated from 0.064W0.33, but in groups this requirement will be affected by social interactions among group members and the amount of competition for the resource. Determining the amount of space for groups of animals is complex, as the amount of useable space can vary with group size and by how group members share space in time. Some studies have been conducted on the way in which groups of domestic fowl use space, but overall, we know very little about the ways in which livestock time-share space, synchronicity in the performance of behaviors, and the effects of spatial restrictions on behavior and welfare.

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Climate matching software (CLIMEX) was used to prioritise areas to explore for biological control agents in the native range of cat's claw creeper Macfadyena unguis-cati (Bignoniaceae), and to prioritise areas to release the agents in the introduced ranges of the plant. The native distribution of cat's claw creeper was used to predict the potential range of climatically suitable habitats for cat's claw creeper in its introduced ranges. A Composite Match Index (CMI) of cat's claw creeper was determined with the 'Match Climates' function in order to match the ranges in Australia and South Africa where the plant is introduced with its native range in South and Central America. This information was used to determine which areas might yield climatically-adapted agents. Locations in northern Argentina had CMI values which best matched sites with cat's claw creeper infestations in Australia and South Africa. None of the sites from where three currently prioritised biological control agents for cat's claw creeper were collected had CMI values higher than 0.8. The analysis showed that central and eastern Argentina, south Brazil, Uruguay and parts of Bolivia and Paraguay should be prioritised for exploration for new biological control agents for cat's claw creeper to be used in Australia and South Africa.

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Absenteeism is one of the major problems of Indian industries. It necessitates the employment of more manpower than the jobs require, resulting in the increase of manpower costs, and lowers the efficiency of plant operation through lowered performance and higher rejects. It also causes machine idleness, if extra manpower is not hired, resulting in disrupted work schedules and assignments. Several studies have investigated the causes of absenteeism (Vaid 1967) for example and their remedy and relationship between absenteeism and turnover with a suggested model for diagnosis and treatment (Hawk 1976) However, the production foremen and supervisor will face the operating task of determining how many extra operatives are to be hired in order to stave off the adverse effects of absenteeism on the man-machine system. This paper deals with a class of reserve manpower models based on the reject allowance model familiar in quality control literature. The present study considers, in addition to absenteeism, machine failures and the graded nature of manpower met within production systems and seeks to find optimal reserve manpower through computer simulation.