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11.
This paper measures technological change, factor demand and inter-factor and inter-fuel substitutability measures for China. We use individual fuel price data and a two-stage approach to estimate total factor cost functions and fuel share equations. Both inter-factor and inter-fuel substitution elasticities are calculated and the change in energy intensity is decomposed into its driving forces. The results suggest that energy is substitutable for capital regionally and for labor nationally. Capital substitutes for energy more easily than labor does. Energy intensity changes vary by region but the major drivers seem to be “budget effect” and the adoption of energy-intensive technologies, which might be embodied in high-level energy-using exports and sectors, capital investment and even old technique and equipment imports. Whether the trend in rising energy intensity continues will be significant for China and the rest of the world. 相似文献
12.
Les Ruddock 《Construction Management & Economics》2013,31(7):553-556
In the context of a truly global market for construction, an international strategy is required to ensure that national and international statistical systems are able to provide accurate and valid information. In many parts of the world the collection of reliable national information on construction activity is not an easy task, and the measurement of comparable, cross-national data can be problematic. This paper considers possible strategies for the improvement of data collection systems in the context of user needs. 相似文献
13.
Biarc approximation of NURBS curves 总被引:4,自引:0,他引:4
An algorithm for approximating arbitrary NURBS curves with biarcs is presented. The main idea is to approximate the NURBS curve with a polygon, and then to approximate the polygon with biarcs to within the required tolerance. The method uses a parametric formulation of biarcs appropriate in geometric design using parametric curves. The method is most useful in numerical control to drive the cutter along straight line or circular paths. 相似文献
14.
Reports a typesetting error in the original article by L. Leventhal (Canadian Psychology, 1994[Jul], Vol 35[3], 283–298). On page 295, the sentence should read "Compared to the old views, the new views might give less weight to the confidence interval and more weight to the probability value of .007 which indicates that the theory performed far better than chance." (The following abstract of this article originally appeared in PA, Vol 82:8115.) P. E. Meehl (1967) attacked significance tests used to appraise directional theoretical predictions. With perfect statistical power, the probability approaches .5 of significance in the predicted direction, even for meritless theories. Feeble theory corroboration results. This article argues that directional predictions, not significance tests, produce the feeble corroboration. The author reviews previous solutions to Meehl, rejecting all except the multiple corroboration solution by D. T. Lykken (1968) and A. Kukla (see record 1991-31958-001). This solution is defended against Meehl's (see record 1991-31961-001) criticisms and extended.… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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16.
Teaching mental patients to use client-centered and experiential therapeutic skills with each other.
Investigated the effects of teaching 42 acute and chronic schizophrenic inpatients (mean age 27.6 yrs) to use client-centered reflective and experiential focusing skills with each other. To determine whether these skills could be learned, Ss were pre- and posttested with the Hinterkopf-Brunswick Talker and Helper Rating Scales. Results indicate that Ss were successful in learning the majority of skills taught. Administration of the Discharge Readiness Inventory revealed significant improvement in experimental Ss as compared to controls on community adjustment potential. In addition to statistical results, patients reported other beneficial effects from the training. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
The construction and performance measurement of a quasi-optical Fresnel rhomb for millimetre wavelengths is described. The Fresnel rhomb was found to operate successfully over W-band with an efficiency ranging from 85 to 95% as the frequency increased from 85 to 99 GHz. Thus, the device offers a wideband performance quarter-wave plate, suitable for quasi-optical systems at millimetre wavelengths 相似文献
18.
This paper presents a methodology to repair flawed migrated models that are designed with knowledge-guided NURBS (KGN). Incompatible traditional CAD packages that are based on NURBS technology have been for many years carrying out the exchange of models and data through either neutral file formats (IGES or STEP) or proprietary formats. The exchange process most often produces poor quality data and results in errors in the migrated CAD models costing the industry billions of dollars every year. While previous studies by large focus on finding means to repair migrated models through patching, we propose to repair errors in CAD models which are generated using KGN through a reconstructing process instead of patching. We have implemented a prototype system to show that employing the right tools on the stored knowledge and data a designer can reconstruct a migrated model based on new local requirements of the receiving system without having to repair it, avoiding delay and corrective processes that only produce patched-up design bases and limiting the effective use of such models. 相似文献
19.
20.
An alternative method of curve interpolation 总被引:1,自引:0,他引:1
Given a point data set that contains several fairly unevenly distributed random points, this paper presents a new paradigm of curve interpolation to fit a curve to the data with end tangent vector constraints. The method uses a base curve, which is subjected to constrained shape manipulations to achieve interpolation, while maintaining end point and end tangent constraints. The algorithm is not sensitive to the distribution or to the randomness of the data, as long as the points represent fairly simple shapes, as in reverse engineering of properly segmented points, or in shape design using simple segments. The method is iterative in nature and allows various forms of adjustments to achieve good results. 相似文献