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31.
This article employs theory to demonstrate the characteristics of successful cross‐disciplinary engineering education collaborations. Specifically, we analyzed data from interviews with 24 recent Journal of Engineering Education authors from engineer‐nonengineer teams. Theoretical frameworks from education and psychology are used to ground the results and contribute to broader research on collaboration across technology and social science disciplines. The data suggest that the way an individual understands and appreciates the nature of knowledge affects the way he or she collaborates with colleagues in different academic disciplines, especially when the disciplines are fundamentally different. Although the literature criticizes engineers for not understanding or respecting other viewpoints, we found that nine engineers and eight nonengineers articulated awareness of their collaborators' perspectives, worked to integrate these into the research, and noted increased satisfaction and quality of work as a result. Recommendations for fostering this type of interdisciplinary integration in engineering education are offered along with suggestions for future research. 相似文献
32.
According to the Air Quality Framework Directive, air pollutant concentration levels have to be assessed and reported annually by each European Union member state, taking into consideration European air quality standards. Plans and programmes should be implemented in zones and agglomerations where pollutant concentrations exceed the limit and target values. The main objective of this study is to perform a long-term air quality simulation for Portugal, using the CHIMERE chemistry-transport model, applied over Portugal, for the year 2001. The model performance was evaluated by comparing its results to air quality data from the regional monitoring networks and to data from a diffusive sampling experimental campaign. The results obtained show a modelling system able to reproduce the pollutant concentrations' temporal evolution and spatial distribution observed at the regional networks of air quality monitoring. As far as the fulfilment of the air quality targets is concerned, there are excessive values for nitrogen and sulfur dioxides, ozone also being a critical gaseous pollutant in what concerns hourly concentrations and AOT40 (Accumulated Over Threshold 40 ppb) values. 相似文献
33.
The purpose of this research review is to open dialog about quantitative, qualitative, and mixed research methods in engineering education research. Our position is that no particular method is privileged over any other. Rather, the choice must be driven by the research questions. For each approach we offer a definition, aims, appropriate research questions, evaluation criteria, and examples from the Journal of Engineering Education. Then, we present empirical results from a prestigious international conference on engineering education research. Participants expressed disappointment in the low representation of qualitative studies; nonetheless, there appeared to be a strong preference for quantitative methods, particularly classroom‐based experiments. Given the wide variety of issues still to be explored within engineering education, we expect that quantitative, qualitative, and mixed approaches will be essential in the future. We encourage readers to further investigate alternate research methods by accessing some of our sources and collaborating across education/social science and engineering disciplinary boundaries. 相似文献
34.
This paper presents a simple method to implement a complete on‐line portable wireless holter including an electrocardiogram (ECG) monitoring, processing, and communication protocol. The proposed algorithm significantly reduces the hardware resources of threshold estimation for ECG compression, using the standard deviation updated with each new input signal sample. The new method achieves superior performance in terms of hardware complexity, channel occupation and memory requirements, while keeping the ECG quality at a clinically acceptable level. 相似文献
35.
36.
Borrego Joaquin Jr.; Timmer Susan G.; Urquiza Anthony J.; Follette William C. 《Canadian Metallurgical Quarterly》2004,72(5):897
The authors used sequential analysis to examine specific interaction patterns between physically abusive mothers and their children following episodes of noncompliance and compliance. Fifteen abusive and 15 nonabusive, low-risk mother-child dyads were observed, and their behaviors were coded for specific interactions. The children in the study ranged in age from 2 to 6 years. Results indicated that after noncompliance occurred, physically abusive mothers were more likely than nonabusive mothers to respond negatively and give another command. When child compliance occurred, there were no group differences in the likelihood of praising their children's prosocial behavior, but physically abusive mothers were less likely than nonabusive mothers to engage in other forms of positive behavior (e.g., positive touch) after compliance. Clinical implications are discussed in the context of working with physically abusive families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
L. P. Borrego J. M. Costa S. Silva J. M. Ferreira 《International Journal of Fatigue》2004,26(12):1-1331
Fatigue crack propagation tests in constant amplitude loading, as well as with single peak overloads, have been performed in AlMgSi1-T6 aluminium alloys with different Mn and Cr contents. Crack closure was monitored in all tests by the compliance technique using a pin microgauge. A moderate stress ratio and a strong material dependence effects on the fatigue crack growth were observed. These effects are discussed in terms of the different dominant closure mechanism (plasticity-induced closure or roughness-induced closure). Roughness-induced closure dominates crack closure in the alloys with higher contents of Mn and Cr elements. In the alloy with a lower content of these elements, plasticity-induced closure is dominant. When roughness-induced closure is the prime pre-overload closure mechanism, the retardation effect is decreased in comparison to when plasticity-induced closure is dominant. 相似文献
38.
Francisco Borrego Isabel Canales Michael G. Lindley 《European Food Research and Technology》1995,200(1):14-23
Proteins of fish muscle undergo chemical and physical changes during frozen storage which may result in, under certain conditions (i. e. long periods of storage, poor freezing practices, temperature fluctuations, etc), loss of quality, reflected mainly by an unacceptable texture as well as an undesirable flavour, odour and colour. In frozen gadoid fish species, most of these changes are caused by the production of formaldehyde in the muscle. Formaldehyde is produced, along with dimethylamine, by the enzymatic reduction of trimethylamine oxide (TMAO). Many aspects of formaldehyde production by TMAO demethylase (TMAOase) have been studied throughout the last decade. In addition, different approaches have been used to investigate the effect of formaldehyde production on protein denaturation and the associated muscle textural changes. Some insight into the reaction between protein and formaldehyde has clarified the possible mechanism of formaldehyde-mediated denaturation. However, evidence of covalent bonding between proteins and formaldehyde, to form crosslinks, has not explained fully the changes observed in fish proteins during frozen storage. The study of cold-induced denaturation of proteins might give new clues for further investigation of the problem. The implications of formaldehyde in toxicological and nutritional issues is also reviewed, as general concern about the safety of food products is a growing field in food science. Finally, different approaches have been proposed to avoid the detrimental action of formaldehyde during frozen storage of gadoid fish; they are some of the practical applications of the knowledge acquired after years of study of different workers in the field. 相似文献
39.
Erhlich Ascitic Tumor and Sarcoma 37 were implanted in mice and afterward the animals were treated with ozone (rectally). A significant decrease in the number of metastasis was obtained. In another study, ozone was applied intraperitoneally, before Lewis' lung carcinoma inoculation. A delayed effect in the tumor development kinetics and in the increase rate of tumor volume in the ozone groups was observed. With regard to the clinical trial, patients with prostatic cancer were treated with cobalt-60 therapy and ozone (rectally), decreasing the presence of side effects (due to radiation treatment) and the prostatic specific antigen figures. However, further investigations are necessary to be performed, in order to be considered the ozone therapy as complementary therapy for cancer. 相似文献
40.
Metal-semiconductor barrier height and semiconductor doping concentration evaluated from room temperature current-voltage and capacitance-voltage data of Schottky barrier diodes exhibit significant error in the presence of an interfacial oxide layer of appreciable thickness (?50 ?). The effective Richardson constant obtained from an activation energy plot of saturation current is shown to provide a sensitive indication of the presence of the interfacial layer. 相似文献