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941.
942.
943.
A laboratory practical examination was used to compare the investigative skills developed in two different types of general‐chemistry laboratory courses. Science and engineering majors (SEM) in the control group used a traditional verification approach (SEM‐Ctrl), whereas those in the treatment group learned from an innovative, inquiry‐based approach (SEM‐Trt). A scoring rubric was developed from their examination sheets to assess six component investigative skills. Results indicated that SEM students in the SEM‐Trt group scored significantly higher than those in SEM‐Ctrl for all six skills. Furthermore, nursing and applied science majors (NonSEM) in the inquiry‐based group (NonSEM‐Trt) wrote significantly better discussions than did SEM students in SEM‐Ctrl group. Overall, competency at the mid‐range level of laboratory skills was attained by most SEM‐Trt students (72.5%) but by only 30.5% of SEM‐Ctrl and 28.6% of NonSEM‐Trt students. Apparently, during the semester students in the SEM‐Trt group were able to use the inquiry‐based method effectively to combine chemical tasks with writing tasks and postlaboratory discussions. One implication of this study for science instructors is that practical examinations can provide useful feedback regarding the quality of the laboratory experience. Another implication is that this study provides evidence for the use of the innovative inquiry‐based laboratory approach to support student learning of high‐level investigative skills. However, students' requisite background knowledge must match the level of these skills.  相似文献   
944.
The purposes of this study were to observe the teaching practices occurring in student teachers' science and mathematics K‐12 classrooms, compare the student teachers' perceptions of their teaching with what was actually occurring in their classrooms, and determine which college faculty members and courses these student teachers felt contributed to the teaching methods they used. Data on each student teacher were gathered via field notes of three classes, an observation protocol completed after each lesson, and an interview. Composites were written for each of the students. The total data set of all composites was examined to see if any patterns generalizable to the whole were evident. Differences between and among grade levels and content areas surfaced and are discussed.  相似文献   
945.
Tracing is a method of assigning flows in an electricity network to particular generators and loads, assuming perfect mixing at each node. It can be used to assign costs to transmission users. We show that the resulting allocation is equal to the Shapley value of an equivalent co-operative game.  相似文献   
946.
947.
Gauss Algebras     
A special class of associative algebras is introduced and studied. A criteria of semisimplicity for suitable category of modules is obtained.  相似文献   
948.
An algebraic approach to harmonic analysis on reductive Lie groups is proposed. The case of complex semisimple Lie groups is considered in details. Some problems for real reductive Lie groups are discussed.  相似文献   
949.
Using the result by D. Gessler, we show that any invariant variational bivector (resp., variational 2-form) on an evolution equation with nondegenerate right-hand side is Hamiltonian (resp., symplectic).  相似文献   
950.
In this note we show how 1-factors in the middle two layers of the discrete cube can be used to construct 2-factors in the Odd graph (the Kneser graph of (k − 1)-sets from a (2k − 1)-set). In particular, we use the lexical matchings of Kierstead and Trotter, and the modular matchings of Duffus, Kierstead and Snevily, to give explicit constructions of two different 2-factorisations of the Odd graph. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
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