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31.
Arne Frick Rainer Neumann und Wolf Zimmermann 《Informatik - Forschung und Entwicklung》1997,12(4):186-195
Zusammenfassung. In diesem Beitrag wird eine Methode zur Konstruktion robuster Klassenhierarchien vorgestellt. Hierzu wird aus den überlegungen
bezüglich der polymorphen Verwendung von Klassen [2] eine Vorgehensweise zur Konstruktion von Klassenhierarchien abgeleitet.
Die Begriffe Konformit?t und Spezialisierung werden verfeinert, indem nicht mehr s?mtliche Methoden einer Klasse, sondern
Teilmengen davon betrachtet werden. Dies führt zum Begriff der partiellen Konformit?t. In Erweiterung von [2] sind partiell konforme Klassen dann polymorph verwendbar, wenn der Anwendungskontext, der sich aus der Benutzung der Klasse ergibt, sich ausschlie?lich auf konforme Methoden erstreckt. Diese Eigenschaft ist
statisch zur übersetzungszeit überprüfbar. Damit k?nnen Fehlbenutzungen bereits zur übersetzungszeit ausgeschlossen werden.
Eingegangen am 24. Dezember 1996 / Angenommen am 15. Oktober 1997 相似文献
32.
A. Zaher S. Li K. T. Wolf F. N. Pirmoradi O. Yassine L. Lin N. M. Khashab J. Kosel 《Biomicrofluidics》2015,9(5)
Implantable drug delivery systems can provide long-term reliability, controllability, and biocompatibility, and have been used in many applications, including cancer pain and non-malignant pain treatment. However, many of the available systems are limited to zero-order, inconsistent, or single burst event drug release. To address these limitations, we demonstrate prototypes of a remotely operated drug delivery device that offers controllability of drug release profiles, using osmotic pumping as a pressure source and magnetically triggered membranes as switchable on-demand valves. The membranes are made of either ethyl cellulose, or the proposed stronger cellulose acetate polymer, mixed with thermosensitive poly(N-isopropylacrylamide) hydrogel and superparamagnetic iron oxide particles. The prototype devices'' drug diffusion rates are on the order of 0.5–2 μg/h for higher release rate designs, and 12–40 ng/h for lower release rates, with maximum release ratios of 4.2 and 3.2, respectively. The devices exhibit increased drug delivery rates with higher osmotic pumping rates or with magnetically increased membrane porosity. Furthermore, by vapor deposition of a cyanoacrylate layer, a drastic reduction of the drug delivery rate from micrograms down to tens of nanograms per hour is achieved. By utilizing magnetic membranes as the valve-control mechanism, triggered remotely by means of induction heating, the demonstrated drug delivery devices benefit from having the power source external to the system, eliminating the need for a battery. These designs multiply the potential approaches towards increasing the on-demand controllability and customizability of drug delivery profiles in the expanding field of implantable drug delivery systems, with the future possibility of remotely controlling the pressure source. 相似文献
33.
Shereen C. Naser Katherine Clonan-Roy Kimberly A. Fuller Elizabeth A. Goncy Nicole Wolf 《Psychology in the schools》2022,59(1):34-50
The purpose of this study is to describe the experiences of lesbian, gay, bisexual, transgender, questioning, intersex, two spirit, and queer (LGBTQ+) youth with school-based sexuality education (SBSE), as well as to document strategies LGBTQ+ youth are using to address their evolving and specific sexual health needs outside of SBSE. Researchers conducted focus groups with 17 adolescents (ages 14–18) from urban and suburban Midwestern cities. Results of this study indicate LGBTQ+ youth find SBSE to be heteronormative, cisgender focused, and primarily focused on pregnancy and disease prevention, which contributes to LGBTQ+ youth experiences of exclusion. In response to SBSE that did not meet student needs, participants reported seeking sexual health information outside of SBSE. Other sources included family and other trusted adults, the Internet, and community resource centers. Students reported variable rates of use and trustworthiness across these resources. Results of this study suggest that school personnel should consider alternatives to traditional SBSE models to meet the needs of LGBTQ+ youth, and that an important part of SBSE should include guidelines for Internet safety. 相似文献
34.
This study identifies proficiency levels in pre-service physics teachers' pedagogical content knowledge (PCK) and reveals how teacher education can promote transitions into higher proficiency. Teacher education plays a fundamental role in supporting pre-service teachers' PCK development. Proficiency levels are a powerful source when evaluating this PCK development because they characterize what learners are likely to be able to know on a specific level. Previous research has presented a model of proficiency levels in pre-service physics teachers' PCK; however, evidence for the model's validity is still lacking. According to the Refined Consensus Model of PCK, factors such as teachers' content knowledge (CK), their teaching experience, and their beliefs about teaching and learning science promote PCK development. Thus, understanding how and when pre-service physics teachers' CK, teaching experience, and beliefs contribute to their proficiency can bring insights into how teacher education can promote PCK development. To address this issue, N = 427 observations of pre-service physics teachers were analyzed. Utilizing the scale anchoring procedure, four different proficiency levels in pre-service physics teachers' PCK were identified. Analyzing these proficiency levels showed that lower levels can be characterized as remembering content-unspecific knowledge, whereas higher levels encompass content-specific strategies to structure and elaborate lessons. Additionally, logistic regression models revealed that pre-service physics teachers' CK is crucial for an increase in PCK proficiency. However, transitions into higher levels of PCK additionally require teaching experience and adequate beliefs about teaching and learning. Thus, our proficiency levels can be used to bring insights into how proficiency in PCK can be supported during teacher education. For example, teacher education should provide courses focusing on the science curriculum and the assessment of student learning to promote pre-service physics teachers' progression in PCK. 相似文献
35.
36.
Klaus Achatz und Wolfram Schulte 《Informatik - Forschung und Entwicklung》1997,12(4):174-185
Zusammenfassung. Wir stellen die neue Methode vor, die auf die formale Entwicklung sequentieller, objektorientierter Softwaresysteme abzielt. ist eine synergetische Kombination aus der semiformalen Methode Fusion und der formalen Spezifikationssprache Object-Z. Die
Methode unterscheidet ausdrücklich Analyse und Entwurf, um die Komplexit?t und die unterschiedlichen Aufgaben der Softwareentwicklung
zu bew?ltigen. In jeder Entwicklungsphase werden Zustands- und Verhaltensspezifikationen in graphischer oder textueller Form
erstellt. Wir geben Beweisverpflichtungen an, um zu gew?hrleisten, da? die entwickelten Spezifikationen formal konsistent
und vollst?ndig sind, und da? das resultierende System zur Ausgangsspezifikation konform ist. Wir illustrieren die Anwendung
von an einem einfachen Beispiel, einem Grapheditor.
Eingegangen am 24. Dezember 1996 / Angenommen am 8.10.1997 相似文献
37.
38.
Michelle M. Neumann Glenn Finger David L. Neumann 《Early Childhood Education Journal》2017,45(4):471-479
As we progress in the 21st century, children learn to become proficient readers and writers of both digital and non-digital texts. Knowledge, skills, and understandings of literacy emerge through sociocultural interactions with non-digital tools (e.g., paper-printed books) and digital tools (e.g., touch screen tablets). However, debate is ongoing over the role that digital experiences play in emergent literacy development. Researchers have voiced the need to conceptualise a common framework for literacy development that considers the emergence of digital literacy skills alongside conventional literacy skills and how these skills might interact during development. This is particularly important in light of the increasing use of digital texts used by young children, such as E-books and digital games. Therefore, this paper proposes a framework that might guide research and practice by examining the relationships between emergent literacy skills, emergent digital literacy skills, and proficiency in reading and writing. 相似文献
39.
Combining entrepreneurial and scientific performance in academia: towards a compounded and reciprocal Matthew-effect? 总被引:2,自引:0,他引:2
The increase of entrepreneurial activity within academia has raised concerns that the research orientation of universities might become ‘contaminated’ by the application-oriented needs of industry. Empirical evidence on this concern is scarce and ambiguous. We examine whether entrepreneurial and scientific performance in academia can be reconciled. Our empirical findings (KU Leuven, Belgium) suggest that both activities do not hamper each other; engagement in entrepreneurial activities coincides with increased publication outputs, without affecting the nature of the publications involved. As resources increase, this interaction becomes more significant, pointing towards a Matthew-effect. We finally suggest that balancing both activities further depends on the institutional policies deployed. 相似文献
40.
Frijters JC Lovett MW Steinbach KA Wolf M Sevcik RA Morris RD 《Journal of learning disabilities》2011,44(2):150-166
This study reports on several specific neurocognitive process predictors of reading outcomes for a sample of 278 children with reading disabilities. Three categories of response (i.e., poor, average, and good) were formed via growth curve models of six reading outcomes. Two nested discriminant function analyses were conducted to evaluate the predictive capability of the following models: (a) an intervention and phonological processing model that included intervention group, phonological awareness, and rapid naming and (b) an additive cognitive neuropsychological model that included measures of memory, visual processes, and cognitive or intellectual functioning. Over and above the substantial explanatory power of the base model, the additive model improved classification of poor and good responders. Several of the cognitive and neuropsychological variables predicted degree of reading outcomes, even after controlling for type of intervention, phonological awareness, and rapid naming. 相似文献