441 research outputs found
Validation of Non-destructive Methodology of Grapevine Leaf Area Estimation on cv. BlaufrÀnkisch (Vitis vinifera L.)
This paper evaluates the application of a statistical model to estimate leaf surface area in grapevines, expressed asleaf area of an individual leaf as well as total leaf area per shoot, including any lateral shoots. Estimating the area ofan individual leaf was based on a formula obtained by regression analysis that uses the sum of length of two inferiorleaf veins as an independent variable. To estimate the leaf area per main shoot and per lateral shoot we used themodel derived from multiple regression analysis that has the following independent variables: the number of leaves,and surface area of the largest and of the smallest leaf on the shoot. High values of the coefficient of determination(r2), as well as satisfactory levels of mean absolute error (MAE), suggest that the applied models appear valid. Theseresults have shown a good fit of observed and predicted values of shoot and lateral leaf areas
Confirmation by Explanation: A Bayesian Justification of IBE
We provide a novel Bayesian justification of inference to the best explanation (IBE). More specifically, we present conditions under which explanatory considerations can provide a significant confirmatory boost for hypotheses that provide the best explanation of the relevant evidence. Furthermore, we show that the proposed Bayesian model of IBE is able to deal naturally with the best known criticisms of IBE such as van Fraassenâs âbad lotâ argument
The propensity interpretation of probability and diagnostic split in explaining away
Causal judgements in explaining-away situations, where multiple independent causes compete to account for a common effect, are ubiquitous in both everyday and specialised contexts. Despite their ubiquity, cognitive psychologists still struggle to understand how people reason in these contexts. Empirical studies have repeatedly found that people tend to âinsufficientlyâ explain away: that is, when one cause explains the presence of an effect, people do not sufficiently reduce the probability of other competing causes. However, the diverse accounts that researchers have proposed to explain this insufficiency suggest we are yet to find a compelling account of these results. In the current research we explored the novel possibility that insufficiency in explaining away is driven by: (i) some people interpreting probabilities as propensities, i.e. as tendencies of a physical system to produce an outcome and (ii) some people splitting the probability space among the causes in diagnostic reasoning, i.e. by following a strategy we call âthe diagnostic splitâ. We tested these two hypotheses by manipulating (a) the characteristics of cover stories to reflect different degrees to which the propensity interpretation of probability was pronounced, and (b) the prior probabilities of the causes which entailed different normative amounts of explaining away. Our results were in line with the extant literature as we found insufficient explaining away. However, we also found empirical support for our two hypotheses, suggesting that they are a driving force behind the reported insufficiency
Validation of the oral health impact profile - 14 in patients with head and neck cancer
The Oral Health Impact Profile-14 (OHIP-14) was designed to assess patients? perception of the impact of oral disorders on their quality of life (QoL). Although the OHIP-14 is now frequently used in patients with head and neck cancer, data related to its measurement properties in this population are scarce. The aim of the present study was to evaluate the reliability and validity of the OHIP-14 in a sample of Serbian patients with head and neck cancer. Data were available for 345 patients (257 [74.5%] males; aged 30-92 years), with head and neck cancer. All patients completed the OHIP-14 and the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-H&N35. Factor analyses, internal consistency reliability (i.e., Cronbach?s ? coefficient), and construct validity were analyzed. The factor analyses confirmed that 14 OHIP items were measuring a single underlying factor. Cronbach?s ? coefficient was 0.98 and corrected item-total correlations ranged 0.77-0.93. Lower OHIP-14 scores (i.e., lower impacts on oral health) were more frequently present among patients who had only surgery as a therapeutic procedure compared to those who had surgery accompanied with radio- and chemotherapy (p< 0.01). Patients with a tumor stage 0-II also had lower OHIP-14 scores compared to those who had a tumor stage III-IV (p< 0.01). The OHIP-14 correlated significantly with the QLQ-C30 and QLQ-H&N35 scales. As a unidimensional instrument, the OHIP-14 provides oral QoL assessments with sound internal consistency reliability and construct validity among patients with head and neck cancer
STRESS, DEPRESSION AND BURNOUT AMONG HOSPITAL PHYSICIANS IN RIJEKA, CROATIA
Background: Six years of recent ongoing economic and structural crisis in Croatia have brought to a significant decrease of
socioeconomic standard in our country, and had an important impact on the health care system. In this background we examined the
prevalence of depression and burnout and their association with work stressors.
Subjects and methods: Cross sectional survey was conducted with self reported questionnaires in 459 hospital physicians in
Rijeka, Croatia. Physicians were divided into three groups: surgical, nonsurgical and diagnostic group. Socio-demographic and
work-related characteristics questionnaire, Occupational Stress Assessment Questionnaire (OSAQ), Maslach Burnout Inventory-
Human Services Survey (MBI-HSS) and Beck Depression Inventory II (BDI-II) were used. Sperman correlation and logistic
regression were calculated to rank association between stressors at work with depression and burnout syndrome.
Results: Response rate was 62.3%, (286/459). Every fifth doctor experienced all examined stressors in the workplace as
stressful. The prevalence of moderate and severe depression was 12.2%. High levels of emotional exhaustion were 43.6%,
depersonalization 33.5%, and lack of personal accomplishment 49.1%. There was no statistical difference in surgical, nonsurgical
and diagnostic groups in depression and all domains of MBI-HSS. Almost all stressors were correlated with depression and burnout
syndrome. Most of the perceived stressors were significant predictors of burnout syndrome and depression.
Conclusions: High levels of burnout domain compared to overall results from similar studies from other countries, placed the
results in our sample on the higher end of the range, while results for depression after adjustment with lower cutoff point would be
similar to those usually found in research literature. Our study showed that burnout is highly prevalent among Croatian physicians.
Target interventions at the workplace should be considered as one of the strategies to reduce negative impact of work stress on
physiciansâ mental health
Explanation and argument
In this thesis I address the relationship between arguments and explanations. In particular, I consider three notions of explanation and the way they relate to arguments. I argue that arguments and explanations should be considered in tandem rather than in isolation. I provide support for this contention throughout the thesis. Specifically, I show how research on argumentation includes considerations of explanation and informs useful distinctions regarding the different notions of explanation (Chapter 1). I then explore the close relationship between arguments and explanations on a specific pattern of reasoning called âexplaining awayâ where I show how explanations can affect the strength of an argument (Chapter 2). In Chapter 3 I provide further theoretical background regarding the different notions of explanations and I discuss factors that constitute âgoodâ explanations. These factors are then explored with respect to the notion of explanations as inference processes and in the context of arguments viewed as causal Bayesian networks. In Chapter 4 I focus on one of the aspects of explanations when embedded in a social context. Here, I take a concern that has been prominent in recent argumentation work, namely the role of the argument source, and pursue it in the context of explanation by examining how the provision of explanations affects the perceived reliability of the explainer. Finally, in Chapter 5 I summarize the results of the thesis and discuss the implications and potential directions for future research
Period Batch Control - A Production Planning System Applied to Virtual Manufacturing Cells
Period Batch Control (PBC) system has been known for its implementation with the classical group technology (GT) cells, and it has been known for its simplicity. The main production planning decisions concern the choice of the period length and the stage number and contents. Also, in order to better integrate the production planning with the application of GT cells at the shop floor, the concept of virtual manufacturing cells has been applied. Since virtual cells configurations are changing periodically, a model for implementing the PBC system into virtual manufacturing cells environment is developed. The model enables alignment of the PBC principles and rules with virtual cell design goals. Model is tested on the case study of furniture production. With the use of scheduling software, different scheduling rules were simulated for four production weeks. The experimental results from these for production weeks show how the choice of PBC parameters impacts the virtual cells configurations, machine sharing and utilization
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