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991.
In this contribution, a theoretical and empirical framework based on work carried out at the Open universiteit (Ou) for a new approach towards the design, production and delivery of flexible, interactive learning materials for distance education is presented.

In the Research and Development centre of the Ou, a project has concentrated on the innovation of current approaches. This framework can also be considered as an advance organizer to reading the remaining articles from the Open universiteit in this issue of Distance Education.

A key feature of the innovation is that during the design phase, course developers have to define ‘models’ of the materials to be developed: a content model, a support model, a student model and the learning path. From a flexibility point of view especially, the ‘student model’ is of importance since it defines the student variables that will be taken into account when developing/ presenting alternative materials (basic content and/or embedded support). A computer‐based system, the ‘Interactive Learning and Course Development Environment (ILCE)’, was developed to support the work of course development teams and tutors on the one hand, and students on the other hand. The development system supports the work of the developers; the delivery system supports the study process of students. The delivery is realised as an on‐line course, on the World Wide Web.

Students start working with the ILCE‐system by following an intake procedure. They can make choices in relation to student variables that have been defined in the student model (profession, study intentions, context, etc.). Next, they can ‘on the fly’ generate a course. Rom the large repository of learning materials only those materials are selected and compiled that are in line with the student model of this specific student Furthermore, they can choose to study the materials on screen and/or make prints of the materials. Of course, in printing the materials they lose the interactive and dynamic possibilities of the computer learning environment  相似文献   

992.
In this article we briefly review the application of electrons in the field of microscopy. Two types of microscopes are discussed, the electron microscope and the tunneling microscope. It is emphasized that in both the applications the electron behaves as a quantum mechanical object.  相似文献   
993.
This paper focuses on the effect that diversity has on the performance and satisfaction of student groups in a computer simulation project. Using structural equation modeling, we find evidence to support the contention of previous research that diversity negatively affects group satisfaction. This finding was strongest for undergraduate groups. While the relationship between diversity and performance is inconclusive, groups that are dominated by one person tend to have below average performance.  相似文献   
994.
The Centrality of Test Use and Consequences for Test Validity   总被引:3,自引:0,他引:3  
What are the origins of consequential validity? What is the role of intended test use in validation? Is the study of unintended effects part of validation? What practical problems does this pose?  相似文献   
995.
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data...  相似文献   
996.
It has become commonplace to hold the view that virtual surrogates for the things that are good in life are inferior to their actual, authentic counterparts, including virtual education, virtual skill-demanding activities and virtual acts of creativity. Virtual friendship has also been argued to be inferior to traditional, embodied forms of friendship. Coupled with the view that virtual friendships threaten to replace actual ones, the conclusion is often made that we ought to concentrate our efforts on actual friendships rather than settle for virtual replacements. The purpose of this paper is to offer a balanced and empirically grounded analysis of the relative prudential value of actual and virtual friendship. That is, do actual and virtual friendships differ when it comes to enhancing our subjective well-being? In doing so, I will discuss a number of presuppositions that lie behind common criticisms of virtual friendship. This will include, among other considerations, their potential for replacing actual friendship, as well as the possibility for self-disclosure, trust, sharing and dynamic spread of happiness in virtual worlds. The purpose is not to arrive at a firm, normative conclusion, but rather to introduce a number of considerations that we should take into account in our individual deliberations over which role virtual friendships ought to have in our unique life situations.  相似文献   
997.
Owen revisited     
  相似文献   
998.
The Antarctic continent on the planet Earth is full of environmental extremes. It is considered as natural stress model. Therefore, the present study examined the effect of harsh environment on the certain salivary markers of 28th Indian Antarctic expeditioners. Thirty healthy men and women (median age 36 year; range 22–61 year) participated in this study. Parameters measured were salivary IgA (SIgA), IgM (SIgM), TGF-β and cortisol level at three different time points: (I) before leaving India on 26th October 2008 for base line level; (II) after 1 month on-board journey on 31st January 2009 in Southern Ocean and (III) after 1 month staying at Maitri, Antarctica on 3rd March 2009. Our observation indicated that Ship borne journey and Antarctic environment increased the SIgA levels while that of SIgM level was not altered on-board but decreased by staying for 1 month at Antarctica. No significant alteration was found in the TGF-β and cortisol level at any point of time. The present study concluded that ship borne journey and Antarctic environment may induce the SIgA level while SIgM level decreased in environmental extremes of Antarctica.  相似文献   
999.
1000.
A simple theory is presented for decoupling a pair of lossless coupled nonuniform transmission lines (CNUTL), with a common return and supporting TEM waves, into two lossless nonuniform transmission lines (NUTL). This theory is independent of the port terminations, symmetry conditions, etc. The method directly relates the line parameters of the lossless CNUTL's to those of the decoupled lines and vice versa; further, the matrix parameters of the CNUTL's as a four-port are explicitly expressed in terms of those of the decoupled lines as two-ports. This theory is then utilized to study the applications of CNUTL's as directional couplers.It is shown that for CNUTL's to behave as a codirectional coupler, each of the decoupled lines should be a proportional line, while for contradirectional coupler action, the two decoupled lines have to be duals of each other. The coupling response of the codirectional coupler is found to be periodic, while the phase shift between coupled and transmitted signals varies linearly with frequency. The coupling response of various contradirectional couplers with smooth transition at one of the ends, for which the decoupled lines are “basic NUTL's with hyperbolic solutions”, are studied in detail. It is shown that all these couplers have a high-pass response and that the CNUTL's with “hyperbolic cosine squared lines” as decoupled lines have the best response of all the CNUTL's considered.  相似文献   
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