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991.
M J Foster 《The Journal of the Operational Research Society》2000,51(1):45-52
Business and hence strategic planning is becoming increasingly international. Within that internationalisation, foreign direct investment (FDI) has become increasingly important, especially in E/SE Asia. A logical step then is to seek appropriate methods for modelling and evaluating those FDIs. Excluding the core financial appraisal the literature is sparse. This paper describes an empirical examination of these issues based on a sample from the UK's top 250 listed companies. The results of responses to a questionnaire are described with elaboration gleaned from eight detailed, follow up interviews. The picture to emerge is one of systematic treatment of the basic financial calculations but fairly rudimentary modelling of non-financial aspects. The treatment of risk was most typically through amendment of cash flows for core business risks and adjustment of the hurdle rate for ‘wilder’ risks. There is discussion of some of the subtler points of ‘wild’ risk's treatment and some outline suggestions for models to tackle other non-financial aspects of overall project evaluation. It is also suggested that the thinking developed may be applicable to a wider class of investment proposals. 相似文献
992.
This paper describes the development and preliminary analysis of a mathematical test targeted for high mathematical ability elementary school students, the Stanford Education Program for Gifted Youth (EPGY) Mathematical Aptitude Test (SEMAT). A version was administered to 248 students, 9–11 years old, in EPGY. The SEMAT was developed because no other satisfactory test was designed or normed for this population. Most standardized tests assess mathematics proficiency for the general population so that gifted students' scores cluster in the few top percentiles. The SEMAT discriminated among this extreme upper end. Item response theory determined proficiency estimates, which were then used as scores to predict various outcomes in EPGY. The SEMAT proved to be a strong predictor of acceleration in EPGY. 相似文献
993.
Dr. C. William Thorpe Stephen J. Cala Janice Chapman Pamela J. Davis 《Journal of voice》2001,15(1):86-104
Recordings of the rib cage and abdominal motions and acoustic output were obtained from five professional opera singers during performance of an aria recorded with two levels of voice projection. The condition of greater projection resulted in a significant increase in the acoustic power in the frequency band 2-4 kHz, relative to the power in the 0-2 kHz band, and a decrease in the mean expiratory flow, implying a move to more efficient vocalization with the greater projection. Also, the condition of greater projection resulted in a larger rib cage, particularly in the lateral dimension, but only a small decrease in the abdominal lateral dimension, suggesting that the greater abdominal support required for a larger projection is obtained by increased activation of abdominal muscles acting medially. 相似文献
994.
The study aimed to assess whether a specific training program in vocal and physical skills could reduce the level of perceived performance anxiety. Eighteen undergraduate performing arts students were divided into two even groups. The experimental group experienced 10 two-hour sessions in a specialized vocal and physical skills training program. The control group received the same number of sessions in text analysis by the same teacher. Ten weeks after the training period, both groups were videotaped delivering a short speech of general interest. The videotaped material was assessed by four judges, using a visual analog scale (VAS). Perceptual variables considered were eight vocal and physical features: physical ease, physical presence, effective gesture use, effective eye contact, correct breath use, suitable pace, vocal variety, speech clarity, and one performance feature: perceived performance anxiety. Results indicated that the particular vocal and physical skills training program used showed positive results in effectively reducing the level of perceived performance anxiety. The experimental group scored significantly higher on each of the eight vocal and physical features and significantly lower on the perceived anxiety feature than the control group. This research has implications for those affected by performance anxiety in vocal presentation. 相似文献
995.
Evaluating the solvation properties of functionalized ionic liquids with varied cation/anion composition using the solvation parameter model 总被引:1,自引:0,他引:1
Twu P Zhao Q Pitner WR Acree WE Baker GA Anderson JL 《Journal of chromatography. A》2011,1218(31):5311-5318
Ionic liquids (ILs) are promising gas chromatography (GC) stationary phases due to their high thermal stability, negligible vapor pressure, and ability to solvate a broad range of analytes. The tunability of ILs allows for structure modification in pursuit of enhanced separation selectivity and control of analyte elution order. In this study, the solvation parameter model is used to characterize the solvation interactions of fifteen ILs containing various cationic functional groups (i.e., dimethylamino, hydroxyl, and ether) and cation types paired with various counter anions, namely, tris(pentafluoroethyl)trifluorophosphate (FAP(-)), bis[(trifluoromethyl)sulfonyl]imide (NTf(2)(-)), thiocyanate (SCN(-)), tricyanomethide (C(CN)(3)(-)), tetracyanoborate (B(CN)(4)(-)), and bis[oxalate(2-)]borate (BOB(-)). The presence of functional groups affected the hydrogen bond basicity, hydrogen bond acidity, as well as dispersion interactions of the resulting ILs, while the change of cation type yielded modest influence on the dipolarity. The switch of counter anions in unfunctionalized ILs produced compounds with higher dipolarity and hydrogen bond basicity. The dipolarity and hydrogen bond basicity of ILs possessing cyano-containing anions appeared to be inversely proportional to the cyano content of the anion. The modification of IL structure resulted in a significant effect on the retention behavior as well as separation selectivity for many solutes, including reversed elution orders of some analytes. This study provides one of the most comprehensive examinations up-to-date on the relation between IL structure and the resulting solvation characteristics and gives tremendous insight into choosing suitable ILs as GC stationary phases for solute specific separations. 相似文献
996.
997.
A simple two-species asymmetric exclusion model is introduced. It consists of two types of oppositely charged particles driven by an electric field and hopping on an open chain. The phase diagram of the model is calculated in the meanfield approximation and by Monte Carlo simulations. Exact solutions are given for special values of the parameters defining its dynamics. The model is found to exhibit two phases in which spontaneous symmetry breaking takes place, where the two currents of the two species are not equal. 相似文献
998.
J. Rapaport R. Alarcon B.A. Brown C. Gaarde J. Larsen C.D. Goodman C.C. Foster D. Horen T. Masterson E. Sugarbaker T.N. Taddeucci 《Nuclear Physics A》1984,427(2):332-356
The 51V(p, n)51Cr reaction has been studied at Ep = 160 MeV using the Indiana University beam-swinger facility. Data have been obtained at several angles up to θL = 20°. The 0° spectrum is used to obtain a ΔL = 0 response function from which Gamow-Teller strength is derived. A shell-model calculation of the GT strength distribution is presented and compared with the experimental results. The M1 strength is also calculated and compared with available results from (e, e') and (p, p') experiments. A comparison is made with other N = 28 nuclei. Effects of a truncated shell-model space are presented. 相似文献
999.
1000.
A method for recording X-ray diffraction patterns of milligram quantities of particulates has been developed. The resulting diffraction patterns are similar to patterns obtained by standard methods. Application of this method to analysis of airborne particulates in the vicinity of a lead smelting operation has demonstrated the practical use of the method. Sample sizes as low as 1.1 mg have produced useful diffraction patterns. 相似文献