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101.
The purpose of the paper has been to present simplified methods that will expedite the calculation of ceiling lighting (Type II). Approximate formulas have been given, which allow ordinary slide-rule calculations to be made very easily for the usual range of variables. Only with rooms having very high domance (or perhaps with extraordinarily high floor reflectance) are the complicated equations of the previous paper (1) needed. These approximate formulas can be represented also by alignment charts, Figs. 2 to 5, which further simplify the work.Either the formulas or the charts may be used to investigate the effect of a change in ?1, ?2, or ?3. However, if reflectances are standardized at recommended values, other methods are possible.In particular, one may use graphs (Fig. 6) or a slide-rule (Figs. 7 and 8). The method of calculation chosen for a specific problem will depend on the problem and on the preferences of the designer. The previous equations and tables (3) may always be used; but in most cases, time can be saved by employing the short-cuts given in the present paper.  相似文献   
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A study is made of separability conditions for the Helmholtz and Laplace equations. Attention is confined to the most useful case for physical applications; namely,
1.
(a) The coordinate system is either cylindrical or it has rotational symmetry, and  相似文献   
103.
Previous interflectance tables have dealt principally with three basic types of lighting (Types I, II, and III). The present paper extends the scope of the interflection method by showing how it can be applied to rooms lighted by hanging luminaires. It is found that most cases arising in practice can be covered by six canonic distributions. The effect of mounting height is handled by means of a simple equation.  相似文献   
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Science writing, such as lab reports, allows students to form a meaningful understanding of scientific concepts. However, students often view scientific writing as unimportant and utilize surface level approaches when completing writing assignments. The current study implemented three experimental interventions (directly-communicated, self-generated, and hybrid) aligned with prior literature and designed to improve the utility value of lab reports in college settings. Participants (n = 1,002) were recruited from 43 lab sections of an introductory biology course at a large southeastern university. Measures of subjective task value (utility value, attainment value, cost, and intrinsic value) were collected pre-, mid-, and post-intervention. The self-generated and hybrid groups exhibited higher self-reported utility value by posttest compared to the control group. Requiring students to generate their own utility value toward a task, followed by a written reflection, increases students' maintained and situational interest for biology laboratory reports.  相似文献   
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The Medical Library Association''s InSight Initiative provides an open and collaborative environment for library and industry partners to discuss vexing problems and find solutions to better serve their users. The initiative''s fifth summit, continuing work from the previous summit, focused on understanding how users discover and access information in the clinical environment. During the summit, participants were divided into working groups and encouraged to create a tangible product as a result of their discussions. At the end of the summit, participants established a framework for understanding users'' pain points, discussed possible solutions to those points, and received feedback on their work from an End User Advisory Board comprising physicians, clinical researchers, and clinical faculty in biomedicine. In addition to the pain point framework, participants are developing MLA InSight Initiative Learning content with modules to educate librarians and publishers about critical aspects of user behavior. The 2020 Insight Initiative Fall Forum will serve as a virtual home for constructive dialogue between health sciences librarians and publishers on improving discovery and access to information.  相似文献   
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