5 resultados para 621, WAST-T

em Deakin Research Online - Australia


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Application layer anycast possesses the property of flexibility, however, all the proposed application layer anycast routing algorithms are based on probing so far. One disadvantage of probing algorithms is that there are too many probing packets, which degrade the network performance, wast network bandwidth. In this paper, we propose an online algorithm, balance algorithm, for application layer anycast. Compared with the probing algorithms, the proposed algorithm has no probing cost at all. We model the two kinds of algorithms, and analyse the performance of the two algorithms. The results show that the online balance algorithm is better than the probing algorithms in terms of performance. A simulation is conducting as future work.

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University education is in a period of flux with emphasis being focused on quality education, competition for students both local and international as well as changes in governmental financial support and direction. It is with this scenario as a backdrop, that universities in an endeavour to obtain economies of scale offer subjects with large student enrolments. This study investigates marketing students’ perception of and participation in marketing subjects relating to teaching quality, staff availability and support, and individual student involvement in marketing education with large enrolments compared to subjects with small enrolments. This research builds on the investigations of effects of class size by Cuseo (2004) and Binney et al (2004). The study used a multi-method approach. Data from a sample of 621 students was analysed using Factor analysis, MANOVA and ANOVA. Students indicated that there was little difference in the quality of learning obtained in small or large classes. Of interest from a marketing perspective, however, is the perception by students that they are more likely to obtain practical assistance and support from tutors in smaller classes. Student perceptions generally show no major differences between large and small classes in relation to subject selection, ability to learn and lecture  attendance. Students expressed a preference for the opportunity to choose from a number of lecture streams available in subjects with large enrolments. Of interest, however is the student belief that they are less likely to actively participate in large lectures than in small lecture environments.

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The post-larvae and fry of Australian native species, including those of species belonging to the family Percichthyidae, are routinely reared to a fingerling size (35-55 mm in length) in fertilised earthen fry rearing ponds. The juveniles of Murray cod (Maccullochella peelii peelii\ trout cod (Maccullochella macquariensis) and Macquarie perch (Macquaria australasicd) (Percichthyidae) are grown in fry rearing ponds at the Marine and Freshwater Resources Institute, Snobs Creek (Vie. Australia) for production of fingerlings for stock enhancement and aquaculture purposes. However, no detailed studies have been undertaken of the productivity of these ponds and factors that influence fish production. An ecologically based study was undertaken to increase the knowledge of pond ecology and dynamics, particularly in relation to the rearing of juvenile Murray cod, trout cod and Macquarie perch in ponds. Over nine consecutive seasons commencing in 1991, water chemistry, plankton, macrobenthos (2 seasons only) and fish were monitored and studied in five ponds located at Snobs Creek. A total of 80 pond fillings were undertaken during the study period. Additional data collected from another 24 pond fillings undertaken at Snobs Creek collected prior to this study were included in some analyses. Water chemistry parameters monitored in the ponds included, temperature, dissolved oxygen pH, ammonia, nitrite, nitrate, orthophosphate and alkalinity. Water chemistry varied spatially (within and between ponds) and temporally (diurnally, daily and seasonally). Liming of ponds increased the total alkalinity to levels that were considered to be suitable for enhancing plankton communities and fish production. Water quality within the ponds for the most part was suitable for the rearing of juvenile Murray cod, trout cod and Macquarie perch, as reflected in overall production (growth, survival and yield) from the ponds. However, at times some parameters reached levels which may have stressed fish and reduced growth and survival, in particular, low dissolved oxygen concentrations (minimum 1.18 mg/L), high temperatures (maximum 34°C), high pH (maximum 10.38) and high unionised ammonia (maximum 0.58 mg/L). Species belonging to 37 phytoplankton, 45 zooplankton and 17 chironomid taxa were identified from the ponds during the study. In addition, an extensive checklist of aquatic flora and fauna, recorded from aquaculture ponds in south-eastern Australia, was compiled. However, plankton and benthos samples were usually numerically dominated by a few species only. Rotifers (especially Filinia, Brachionus, Polyarthra, and Asplanchnd), cladocerans (Moina and Daphnid) and copepods (Mesocyclops and Boeckelld) were most abundant and common in the plankton, while chironomids (Chironomus, Polypedilum, and Prodadius) and oligochaetes were most common and abundant in the benthos. Both abundance and species composition of the plankton and macrobenthos varied spatially (within and between ponds) and temporally (diurnally, daily and seasonally). Chlorophyll a concentrations, which ranged from 1.8 to 184 \ig/L (mean 29.37 ng/L), initially peaked within two weeks of filling and fertilising the ponds. Zooplankton peaked in abundance 2-4 weeks after filling the ponds. The maximum zooplankton density recorded in the ponds was 6,621 ind./L (mean 721 ind./L). Typically, amongst the zooplankton, rotifers were first to develop high densities (2nd-3rd week after filling), followed by cladocerans (2nd-4th week after filling) then copepods (2nd-5th week after filling). Chironomid abundance on average peaked later (during the 5th week after filling). The maximum chironomid density recorded in the ponds was 27,470 ind./m2 (mean 4,379 ind./m2). Length-weight, age-weight and age-length relationships were determined for juvenile Murray cod, trout cod and Macquarie perch reared in ponds. These relationships were most similar for Murray cod and trout cod, which are more closely related phylogenetically and similar morphologically than Macquarie perch. Growth of fish was negatively correlated with both size at stocking and stocking biomass. Stocking density experiments showed that, at higher densities, growth offish was significantly reduced, but survival was not affected. The diets of juvenile Murray cod trout cod and Macquarie perch reared in fry ponds were similar. The cladocerans Moina and Daphnia, adult calanoid and cyclopoid copepods and the chironomids, Chironomus, Polypedilum and Procladius were the most commonly occurring and abundant prey. Selection for rotifers and copepod nauplii was strongly negative for all three species of fish. Size range of prey consumed was positively correlated with fish size for trout cod and Macquarie perch, but not for Murray cod. Diet composition changed as the fish grew. Early after stocking the fish into the ponds, Moina was generally the more common prey consumed, while in latter weeks, copepods and chironomids became more abundant and common in the diet. On a dry weight basis, chironomid larvae were the most important component in the diets of these fish species. Selective feeding by fish on larger planktonic species such as adult copepods and cladocerans, may have influenced the plankton community structure as proposed by the trophic cascade or top -down hypothesis. The proximate composition and energy content of Murray cod, trout cod and Macquarie perch, reared in the ponds did not vary significantly between the species, and few significant changes were observed as the fish grew. These results suggested that the nutrient requirements of these species might not vary over the size range of fish examined. Significant differences in the proximate composition of prey were observed between species, size of species and time of season. The energy content of prey (cladocerans, copepods and chironomids) on a pond basis, was closely related to the abundance of these taxa in the ponds. Data collected from all pond fillings during the present study, along with historical data from pond fillings undertaken prior to this study, were combined in a data matrix and analysed for interactions between pairs of parameters. In particular, interactions between selected water chemistry parameters, zooplankton and chironomid abundance indicators were analysed to identify key factors that influence fish production (growth, survival, condition and yield). Significant correlations were detected between fish production indicators and several water chemistry and biota (zooplankton and chironomids) parameters. However, these were not consistent across all three species of fish. These results indicated that the interactions between water chemistry, biota and fish were complex, and that combinations of these parameters, along with other factors not included in the present study, may influence fish production in these ponds. The present study, showed that more stringent monitoring of fry rearing ponds, especially water quality, zooplankton and benthos communities and fish, combined with an associated increase in understanding of the pond ecosystem, can lead to substantial improvements in pond productivity and associated fish production. In the present study this has resulted in a general increase in fish survival rates, which became less variable or more predictable in nature. The value of such knowledge can provide managers with a more predicative capacity to estimate production of ponds in support of stock enhancement programs and provision of juvenile for aquaculture grow-out.

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Although several studies in social psychology suggest that male participants are more likely than female ones to engage in individuating behaviors, other studies have found no gender differences in willingness to perform individuating acts. This study posits that differences in findings across past investigations may be attributed to the chosen domain of individuating behavior. The content of the Individuation Scale (Maslach, Stapp, & Santee, 1985) is examined in terms of Bakan's (1966) agency‐communion theory to identify two types of individuating behaviors that are consistent with men's gender role orientations (i.e., eliciting conflict, leadership), one type of individuating behavior that is consistent with women's gender role orientations (i.e., personal disclosures), and a gender‐neutral type of individuation (i.e., performance). Responses to the scale are obtained from a sample of business school students (N = 273) and a more heterogeneous mail survey sample (N = 621). A sequence of measurement invariance tests of a 4‐factor correlated model of the individuation measure indicates a high degree of equivalence in the meaning of the measure across gender groups. Subsequent latent‐means structure analysis examines gender differences in willingness to perform the 4 types of individuation behaviors captured in the scale. In the student sample, there were no mean differences in willingness to perform any of the 4 types of individuating acts. However, in the mail survey sample, findings of mean differences supported hypotheses derived from agency‐communion theory: For men as compared with women, the latent means for leadership and eliciting conflict were higher and the latent mean for personal disclosure was lower.

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Background: Substantial numbers of cancer patients use complementary medicine therapies, even without a supportive evidence base. This study aimed to evaluate in a randomized controlled trial, the use of Medical Qigong (MQ) compared with usual care to improve the quality of life (QOL) of cancer patients. Patients and methods: One hundred and sixty-two patients with a range of cancers were recruited. QOL and fatigue were measured by Functional Assessment of Cancer Therapy—General and Functional Assessment of Cancer Therapy—Fatigue, respectively, and mood status by Profile of Mood State. The inflammatory marker serum C-reactive protein (CRP) was monitored serially. Results: Regression analysis indicated that the MQ group significantly improved overall QOL (t144 = −5.761, P < 0.001), fatigue (t153 = −5.621, P < 0.001), mood disturbance (t122 =2.346, P = 0.021) and inflammation (CRP) (t99 = 2.042, P < 0.044) compared with usual care after controlling for baseline variables. Conclusions: This study indicates that MQ can improve cancer patients’ overall QOL and mood status and reduce specific side-effects of treatment. It may also produce physical benefits in the long term through reduced inflammation.