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51.
This paper discusses implications of the convergence of legal and organizational issues in the context of developing and implementing digital government projects in large urban settings. By the convergence of legal and organizational issues we refer to two important aspects of urban government: (1) the close relationship between legal/policy structures and the way government is organized and functions, and (2) the way the legal/policy elements interact with organizational dynamics and work cultures to influence digital government projects (and government activities generally). It is our contention that convergence in the organizational and legal/policy context is a powerful determinant of how these projects develop and how likely they are to succeed. Therefore the understanding of this convergence and related dynamics is critically important to planning and designing both policy to promote digital government and particular digital government projects themselves. Illustrations of this convergence and its consequences are presented. They are based on research involving two digital government projects in urban settings: development of a management information system for homeless shelter administration and a developing a system for sharing information among New York City agencies.  相似文献   
52.
This investigation identifies demographic, media, and social correlates of verbally aggressive communication in adolescence. Mail surveys were completed and returned by 2,300 adolescents between the ages of 13 and 15. These adolescents were asked about the prevalence of verbal and physical aggression, the context in which it occurred, demographics, and the interpersonal and media influences in their lives. The results indicate that verbal aggression is widespread, that committing and experiencing verbal aggression is largely reciprocal, that there is a strong relationship between committing verbal and physical aggression, and that peer social influence and listening to violently oriented music are mildly related to verbal aggression in adolescents. These findings suggest more resources should be allocated to teaching adolescents to understand and control verbal aggression. Further, they provide important answers to many prevention and intervention programmatic questions, including context, content, and targeting concerns. Since the negative consequences of verbal aggression are severe and long lasting, decreasing this destructive communication behavior should significantly improve the lives of many adolescents. These and other practical implications are expanded upon and discussed.  相似文献   
53.
To evaluate Information Retrieval Systems on their effectiveness, evaluation programs such as TREC offer a rigorous methodology as well as benchmark collections. Whatever the evaluation collection used, effectiveness is generally considered globally, averaging the results over a set of information needs. As a result, the variability of system performance is hidden as the similarities and differences from one system to another are averaged. Moreover, the topics on which a given system succeeds or fails are left unknown. In this paper we propose an approach based on data analysis methods (correspondence analysis and clustering) to discover correlations between systems and to find trends in topic/system correlations. We show that it is possible to cluster topics and systems according to system performance on these topics, some system clusters being better on some topics. Finally, we propose a new method to consider complementary systems as based on their performances which can be applied for example in the case of repeated queries. We consider the system profile based on the similarity of the set of TREC topics on which systems achieve similar levels of performance. We show that this method is effective when using the TREC ad hoc collection.  相似文献   
54.
Many scientists and coaches are interested in mechanical power produced during cycling, and use Schoberer Rad Me\technik (SRM) bicycle power cranks to obtain this data. However, it has been expensive and difficult to calibrate SRM cranks, causing much of the collected data to be unreliable. We present a static method, derived from first principles, for obtaining a calibration factor for SRM cranks. A known mass and lever arm (chainring of a known diameter) are used to apply a known torque load to the instrument in four positions, and the output frequencies are used to calculate the calibration factor in Hz/Nm. The reproducibility of this method is ±0.01 Hz/Nm, which is acceptable for the application of the instrument, which is measurement of mechanical power application by cyclists at the crank. The method is reliable, inexpensive, and easy to set up, and will allow higher confidence in data collected using SRM power cranks. We recommend calibration of the power meter once every six months because of the measured drift of the calibration factor over time.  相似文献   
55.
动态在线讨论:交互式学习环境中的深层学习   总被引:3,自引:0,他引:3  
本文阐述了在远程教育中进行面向深层学习的动态在线讨论的一个框架。该框架建立在信息、方法和认知等三个普遍性过程的基础上。在本框架中进行动态讨论的结构包括三种在线讨论的类型,即灵活的同伴、结构化的主题和协作性任务讨论。该框架在一门有关教学多媒体设计的在线研究生课程中使用过两个学期。创建动态讨论的策略是为了促进不同学习者之间的在线交互,并有助于设计能实现有效交互的任务。学生通过设计的任务产生了接受性学习,在此基础上促进了适应性学习,并且激发了他们促进深层学习的认知能力。该框架及动态讨论的策略提供了一个在线学习环境,在这样的环境中学生的学习超越了既定的课程目标。  相似文献   
56.
In this article, Anthony Feiler, senior lecturer in the Graduate School of Education at the University of Bristol, and Elaine Logan, lecturer in early years education at the City of Bristol College, present a case study of a child who made strong progress with literacy during his first year at school. The child and his family participated in the Literacy Early Action Project (LEAP), a home-visiting scheme for children judged by school staff to be at risk of struggling with literacy. A teaching assistant made weekly home visits during the year and developed literacy support activities with the child's mother and grandparents. Five key factors underpinning the child's progress are identified here: the flexibility in the teaching assistant's approach that enabled extended family members to become engaged in literacy support; the teaching assistant's sensitivity to family culture; the playful approach to learning adopted by the teaching assistant; putting the child at the centre of the intervention; and the existence of a school culture that strongly promoted involvement for parents. Anthony Feiler and Elaine Logan conclude that teaching assistants in the UK might be given more scope to develop support strategies for early childhood education that involve collaborative work with parents.  相似文献   
57.
Renewed interest in natural materials as food flavors and preservatives has led to the search for suitable essential oils. Moringa oleifera seed essential oil was extracted by solvent-free microwave and hydrodistillation. This study assessed its chemical constituents. Cytotoxicity of the oils was investigated using hatchability and lethality tests on brine shrimps. A total of 16 and 26 compounds were isolated from the hydrodistillation extraction (HDE) and solvent-free microwave extraction (SME) oils, respectively, which accounted for 97.515% and 97.816% of total identifiable constituents, respectively. At 24 h when the most eggs had hatched, values of the SME (56.7%) and HDE (60.0%) oils were significantly different (P<0.05) from those of sea water (63.3%) and chloramphenicol (15.0%). Larva lethality was different significantly (P<0.05) between HDE and SME oils at different concentrations and incubation periods. The median lethal concentration (LC50) of the oils was >1000 mg/ml recommended as an index for non-toxicity, which gives the oil advantage over some antioxidant, antimicrobial, therapeutic, and preservative chemicals.  相似文献   
58.
As a key element in teacher education programmes, action research is a learning process in which pre-service teachers inquire, reflect on and improve their teaching practices. This qualitative study sought to understand what enhanced or hindered Thai pre-service teachers' action research projects during their student teaching. This study drew upon written reflections, focus-group interviews and observations of seminar sessions. Data analysis was inductive, involving categorical aggregation followed by a search for correspondence and patterns. The results indicated that the pre-service teachers misunderstood action research, and also held a negative attitude toward it, both of which led them to superficial analyses of practice. They struggled with time limitations, data gathering and interpretation strategies. In spite of the struggles they experienced, these pre-service science teachers did learn more about the action research through collaboratively working with cooperating teachers and university supervisors and on-campus seminar discussions held concurrently with the fifth year internship. Recognizing and understanding the reasons and thinking patterns at the root of these teachers' difficulties with learning about action research can form the basis for reflecting on and rethinking the components of science teacher preparation programmes in Thailand.  相似文献   
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