Parallel access by butterfly networks for any degree permutation polynomial and ARP interleavers

Using more processors for parallel turbo decoding is an important issue to speed up the processing at the receiver of a communication system. Butterfly networks used to map the addresses of extrinsic values represent an elegant and simple solution in parallel turbo decoding. Recently, it has been shown that quadratic permutation polynomial (QPP) interleavers allow an easy way to compute the control bits for a butterfly network. In this paper we show that not only QPP interleavers, but any degree permutation polynomial (PP) interleavers and almost regular permutation (ARP) interleavers also allow the same easy way to compute the control bits required in butterfly networks. As a consequence, it is useful to apply the butterfly networks in parallel turbo decoding when using these performant algebraic interleavers.     

Influence of Process Parameters on Chlorinated Biocide Decontamination by li-CO2 on Artificially Contaminated Model Materials

ABSTRACT

Previously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO₂ was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO₂ decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present.     

四月的诗

晨月圆圆,金光灿烂,悬挂在雾霭蓝天上;高耸白杨独自摇晃,鸟鸣声声起伏不断,四月的第一天,朋友!在这愚人的四月,月亮闪着金光,如小巧温柔的太阳。The morning moon is round and goldUp in the misty milk-blue sky;The towering poplar sways alone;The birds are shouting one     

Family Risk and Externalizing Problems in Chilean Children: Mediation by Harsh Parenting and Emotional Support

Latent class analysis and multigroup mediation were used with 8,860 families in Chile to identify risk groups varying in socioeconomic status, family structure, and maternal depression, to determine whether profiles differed in children’s development of externalizing problems (EP) from 35 to 61 months, and maternal parenting that predicted EP. Four groups were identified: one no-risk profile and three risk profiles, impoverished and undereducated, depressed and impoverished, and father-absent and impoverished. All classes differed in EP. Maternal emotional support and harsh parenting were differentially associated with the development of EP across the three risk groups, relative to the low-risk group. Thus, specific constellations of adversities differentially predicted children’s EP and socialization processes mediating links between risk and EP. Implications are discussed.     

Effects on response time and accuracy of technology-enhanced cloze tests: an eye-tracking study

Educational technology research and development - The transition from paper-based tests to corresponding computer-administered tests allows for the incorporation of improved interfaces that support...     

‘Family comes in all forms,blood or not’: disrupting dominant narratives around the patriarchal nuclear family

ABSTRACT

After nearly 25 years of democracy, lives of young South Africans are still profoundly shaped by the legacies of apartheid. This paper considers how these differences are produced, maintained and disrupted through an exploration of changing narratives developed by a small group of South African pre-service teachers, with a particular focus on the narratives developed around discourses of fatherhood generally and absent fathers in particular. We draw on interviews conducted with three students in which we discussed their digital stories and literature reviews. In this paper, we draw attention to the limitations of digital storytelling and the risks such autobiographical storytelling presents of perpetuating dominant narratives that maintain and reproduce historical inequalities. At the same time, in highlighting ways in which this risk might be confronted, the paper also aims to show the possibilities in which these dominant narratives may be challenged.     

Learning Environments: The Case for Evidence-Based Practice and Issue-Driven Research

In his thought-provoking review of current trends in educational research, Winn offers advice to practitioners and to researchers concerning the role of computer-based simulations in education (Winn, W. (2000). Educ. Psychol. Rev. 14, 331–351). In this critique, I offer two proposals for consideration by those who wish to make practical recommendations about learning environments: (1) Recommendations for practice should be based on specifically relevant evidence. (2) The available methods for collecting evidence should not exclude controlled experiments; instead, researchers should be free to choose among experimental or observational methods, use quantitative or qualitative measures, focus on artificial or naturalistic settings, and invent new techniques as needed. In short, I join the call for evidence-based practice and issue-driven research.     

Enjoyment,Boredom, Anxiety in Elementary Schools in Two Domains: Relations With Achievement

This study investigated the enjoyment, boredom, and anxiety of elementary school students and the relations of these emotions with achievement in two domains. Seven-hundred-and-sixty-seven second- and fourth-graders completed an adaptation of the Achievement Emotions Questionnaire-Elementary School (AEQ-ES: Lichtenfeld, Pekrun, Stupnisky, Reiss, & Murayama, 2012) assessing their emotions in their native language and mathematics. The hierarchical model of the instrument was invariant across countries (Italy, Germany, United States), grades, gender, and domains. Anxiety related negatively to achievement, while enjoyment related positively to achievement only in mathematics. Second-graders reported more enjoyment and less boredom and anxiety than fourth-graders. Overall, mathematics resulted in better emotions than native language. The results have implications for future research on achievement emotions in elementary school.     

Bilingual-bicultural models of literacy education for deaf students: considering the claims

As Carolyn Ewoldt (1996) points out '[M]uch has been written of late about the viability of a bilingual focus in deaf education.' While these writings are necessary to the ongoing pedagogical dialogue in the field, much of the rhetoric suffers because, rather than truly adopting a 'holistic perspective', arguments and positions focus only on selected aspects of the relevant theoretical and research information. If proponents of bilingual education for deaf children truly rely on 'research on the benefits of native sign language and from theoretical and research support coming from other disciplines' (Ewoldt, 1996, p. 5) to support their claims, then these research and theoretical supports must be examined as comprehensively, and holistically, as possible. Weaving together only a few threads of theory and research does not create the fabric for a pedagogical position that can withstand close scrutiny and analysis.In this article, we will touch on some of the major claims made in explications of bilingual models of literacy education for deaf students (Baker, 1997; Livingston, 1997; Mashie, 1995; Mason & Ewoldt, 1996). Our goal is to broaden the scope of the discussion on some of the major arguments and to encourage an expanded dialogue in this ongoing debate. It is not our aim to argue against the concept of bilingual education for deaf students nor to advocate the exclusion of native sign languages from the classroom. Rather, we support the concept of a bilingual education for deaf students with native sign languages playing a key role; however, we contend that the model as it is currently conceived requires further scrutiny and analysis.