16,852 research outputs found
Limnological study of Zealand Pond, White Mountains, New Hampshire
Zealand Pond, New Hampshire, was chosen as the site of a remote lake study. Data were collected between July 18 and August 29,1997. Zealand Pond had a relatively high pH (6.3-6.9) and alkalinity (2.3- 3.1 mg CaCO3 /liter), considering its small size and elevation (752 m). The lake was not thermally stratified, presumably due to its shallow depth and exposure to wind. Zealand Pond had a diverse zooplankton community, with two calanoid copepod species (Hesperodiaptomus wilsonae and Leptodiaptomus ashlandi), two cyclopoid copepods (Mesocyclops edax and Ectocyclops phaleratus), six cladoceran species (Daphnia ambigua, Daphnia pulex, Ceriodaphnia reticulata, Bosmina longirostris, Alona costata, and Polyphemus pediculus), and two rotifer species (Keratella taurocephala and Conochilus sp.). Densities of zooplankton ranged from 57.6 (Hesperodiaptomus) to 0.04 (Alona) animals per liter. Zooplankton species were documented with photographs and key identifying features. Low densities of fish were also present in the lake. Features of Zealand Pond are compared to other high altitude lakes
Evaluation of a ‘whole programme’ strategy for developing social work students’ skills in communication with children and young people
Improving outcomes for children and young people through effective social work practice requires skilled engagement and communication with the children and young people themselves. Social work qualification programmes play a key role in ensuring practitioners are equipped for this role. However, recent research by the presenter and colleagues noted an absence of empirical evidence on what constitutes effective methods of teaching and learning communication skills with children and a lack of academic consensus regarding curriculum structure, content or delivery, in England, Wales and Northern Ireland at least. That previous research did enable the authors, though, to identify a taxonomy of knowledge, values, personal qualities and micro-skills which underpin effective communication with children and young people in social work practice and, consequently, what might need to be covered by qualifying programmes. Hypotheses were developed regarding the kinds of pedagogical methods which might be effective in teaching these. Rather than considering disparate ways of teaching discrete skills, a ‘whole programme’ approach was proposed. This approach was then instituted in a Masters degree qualifying social work programme in England, where this presenter teaches. This paper will present the findings of a 2 year evaluation of the effectiveness of this pedagogical approach (linked to the Outcomes in Social Work Education project). Qualitative and quantitative data was collected at four points during the programme, including at the beginning and end of the programme. Quantitative measures included students rating their subjective perception of what aspects of the programme (or other experiences) contributed to their enhanced confidence in communicating with children and young people. Qualitative measures included a vignette tool which indicated students’ underpinning knowledge about what constituted effective communication and how best to achieve it. The paper will end with considering implications for both curriculum structure and programme evaluation
Computer program simplifies design of rotating components of turbomachinery
Digital computer program performs stress analysis and burst speed calculations on rotating axisymmetric turbomachinery components. The computer printout contains the displacement of each nodal point, the stress at the center of each element, the average tangential stress within the component, and the burst speed
The Tell-Tale “Heart”: Determining “Fair” Use of Unpublished Texts
Copyright laws require that courts consider at least four factors in determining whether a quotation or close paraphrase of another\u27s unpublished work without permission falls under fair use. Several cases involving fairuse are discussed
Circumstellar shells, the formation of grains, and radiation transfer
Advances in infrared astronomy during the last decade have firmly established the presence of dust around a large number of cold giant and supergiant stars. To describe the properties of stars and to understand their evolution, it is necessary to know the nature of the giants and their influence on stellar radiation. Two questions are considered: the formation of grains around cold stars and the modification of stellar radiation by the stellar shell
Covering Arrays and Fault Detection
Given their several applications, covering arrays have become a topic of significance over the last twenty years in both the mathematical and computer science fields. A covering array is a N × k array with strength t, k rows of length N, entries from the set {0, 1, ..., v − 1}, and all vt possible combinations occur between any t columns, where N,k,t, and v are positive integers. The focus of our research was to explore the different constructions of strength two and strength three covering arrays, to find better covering arrays (i.e. more cost and time efficient covering arrays), and to see if covering arrays can detect a fault in a system. Through analyzing the covering arrays that we constructed, we were able to successfully prove that in general, a covering array of strength k + 1 can detect a single fault between any k or fewer variables in a system. Some areas of future research would include finding the location of a fault in a system or detecting two or more faults in a system
Willingness-to-pay for Local Milk-based Dairy Product in Senegal
This paper aims to evaluate Senegalese consumers' willingness-to-pay (WTP) for local fresh milk-based products, in opposition to the ones produced with imported powder. Using data from a choice-based-conjoint analysis conducted on 400 households in the re- gion of Dakar, we evaluate the premium that consumers are willing to pay for fresh raw material (rather than powder) in the composition of sour milk. Based on an Ordered Probit Model, the results show evidence for a positive WTP for fresh raw material, which may be seen as a strong indication of preference for local products. This WTP greatly depends on the characteristics of the households. Wealthier house- holds are willing to pay more than the medium households, while big households are ready to pay much less than the base category ones. Obviously, some niche markets exist, that producers may target to sell the local milk-based dairy products. However, more infor- mation has to be provided about the composition of dairy products, as consumers are not currently able to distinguish both types of raw material, even if they are willing to pay more for one of them.
Explanation-Based Auditing
To comply with emerging privacy laws and regulations, it has become common
for applications like electronic health records systems (EHRs) to collect
access logs, which record each time a user (e.g., a hospital employee) accesses
a piece of sensitive data (e.g., a patient record). Using the access log, it is
easy to answer simple queries (e.g., Who accessed Alice's medical record?), but
this often does not provide enough information. In addition to learning who
accessed their medical records, patients will likely want to understand why
each access occurred. In this paper, we introduce the problem of generating
explanations for individual records in an access log. The problem is motivated
by user-centric auditing applications, and it also provides a novel approach to
misuse detection. We develop a framework for modeling explanations which is
based on a fundamental observation: For certain classes of databases, including
EHRs, the reason for most data accesses can be inferred from data stored
elsewhere in the database. For example, if Alice has an appointment with Dr.
Dave, this information is stored in the database, and it explains why Dr. Dave
looked at Alice's record. Large numbers of data accesses can be explained using
general forms called explanation templates. Rather than requiring an
administrator to manually specify explanation templates, we propose a set of
algorithms for automatically discovering frequent templates from the database
(i.e., those that explain a large number of accesses). We also propose
techniques for inferring collaborative user groups, which can be used to
enhance the quality of the discovered explanations. Finally, we have evaluated
our proposed techniques using an access log and data from the University of
Michigan Health System. Our results demonstrate that in practice we can provide
explanations for over 94% of data accesses in the log.Comment: VLDB201
Cultural differences in complex addition: efficient Chinese versus adaptive Belgians and Canadians
In the present study, the authors tested the effects of working-memory load on math problem solving in 3 different cultures: Flemish-speaking Belgians, English-speaking Canadians, and Chinese-speaking Chinese currently living in Canada. Participants solved complex addition problems (e.g., 58 + 76) in no-load and working-memory load conditions, in which either the central executive or the phonological loop was loaded. The authors used the choice/no-choice method to obtain unbiased measures of strategy selection and strategy efficiency. The Chinese participants were faster than the Belgians, who were faster and more accurate than the Canadians. The Chinese also required fewer working-memory resources than did the Belgians and Canadians. However, the Chinese chose less adaptively from the available strategies than did the Belgians and Canadians. These cultural differences in math problem solving are likely the result of different instructional approaches during elementary school (practice and training in Asian countries vs. exploration and flexibility in non-Asian countries), differences in the number language, and informal cultural norms and standards. The relevance of being adaptive is discussed as well as the implications of the results in regards to the strategy choice and discovery simulation model of strategy selection (J. Shrager & R. S. Siegler, 1998)
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