Keng‐Hoong Yim  Gregory L. Whiting  Craig E. Murphy  Jonathan J. M. Halls  Jeremy H. Burroughes  Richard H. Friend  Ji‐Seon Kim 《Advanced materials (Deerfield Beach, Fla.)》2008,20(17):3319-3324

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Alexander Zakrassov  Gregory Leitus  Sidney R. Cohen  Ron Naaman 《Advanced materials (Deerfield Beach, Fla.)》2008,20(13):2552-2555

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Gregory A. Keoleian  Alan W. Phipps  Tad Dritz  Dov Brachfeld 《Packaging Technology and Science》2004,17(2):85-103

A life cycle assessment was conducted to evaluate the environmental performance of the yogurt product delivery system used by Stonyfield Farm. A life cycle model was developed which included material production, manufacturing and disposition for primary and secondary packaging, as well as the related transportation links between these stages and filling, retail and the point of consumption. Product delivery systems (PDS) that utilized 4, 6, 8 and 32 oz polypropylene (PP) cups and 2 oz linear low‐density polyethylene (LLDPE) tubes were analysed. Ten strategies for improving the environmental performance of these systems were proposed and their impacts on the total life cycle burden were analysed. The life cycle energy consumption for the 2, 4, 6, 8 and 32 oz containers was 4050, 4670, 5230, 4390 and 3620 MJ/1000 lb yogurt delivered to market, respectively. Material production of the primary packaging accounted for 58% of the life cycle energy, while Distribution 3 (yogurt delivery to distributors/retailers) alone accounted for one‐third of the life cycle total energy. The life cycle solid waste profile showed that as the container size decreased, the solid waste burden increased, from 27.3 kg (32 oz) to 42.8 kg (6 oz) per 1000 lb yogurt delivered to market. This relationship was even more pronounced for the 4 oz (47.5 kg) and 2 oz (56.2 kg) product delivery systems. The greatest potential improvements in the environmental performance of the PDS are achievable through redesigning the primary packaging and using alternative manufacturing techniques for the yogurt cups. Shifting from injection moulding to thermoforming of 32 oz container reduces the life cycle energy and solid waste by 18.6% and 19.5%, respectively, primarily due to light‐weighting. Elimination of lids for 6 oz and 8 oz containers provided similar benefits. Consumers purchasing yogurt in 32 oz instead of 6 oz containers can save 14.5% of the life cycle energy and decrease solid waste by 27.2%. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

    

Gregory J. Wagner  Wing Kam Liu 《International journal for numerical methods in engineering》2000,47(8):1367-1379

Collocation methods for applying essential boundary conditions are defined as those methods in which conditions are enforced exactly at a discrete set of boundary nodes. In mesh‐free methods, this is usually accomplished by replacing rows of the matrix equations which result from discretization of the weak form with equations which ensure the enforcement of boundary conditions. In this paper, an inconsistency in this method is pointed out, and a correction is derived. Numerical test are done on one‐ and two‐dimensional equations; it is shown that convergence rates decrease with the use of the invalid traditional collocation and are restored with the corrected method. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

    

Baker  Jeff; McCutcheon  Stephen; Keilin  W. Gregory 《Canadian Metallurgical Quarterly》2007,1(4):287

The internship has long been considered the capstone experience in the sequence of doctoral education in professional psychology. Since at least 1999, the number of available internship positions in the United States and Canada has been outstripped by the number of students seeking these positions. The resulting imbalance between supply and demand for internship positions has grown substantially since 2002 and now should be considered to have reached crisis proportions. Although no complete solution to this imbalance is imminently feasible, a comprehensive approach to addressing the crisis requires that both the supply of internships and the growth in demand be addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

    

Jeeho Lee  Gregory L. Fenves 《International journal for numerical methods in engineering》2001,50(2):487-506

Three‐dimensional and plane stress formulations of the return‐mapping algorithm for a class of plastic‐damage models are derived using the spectral decomposition form of the stress. An efficient plane stress computation scheme based on the spectral return‐mapping algorithm is developed. The consistent algorithmic tangent stiffness for the present algorithm is formulated. The validation and performance of the present return‐mapping algorithm is demonstrated by numerical examples. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

    

Gregory J. Wagner  Wing Kam Liu 《International journal for numerical methods in engineering》2001,50(3):507-524

The finite‐element method, when used with a basis made up of piecewise polynomials, often requires the generation of a very fine computational mesh in order to capture localized solution phenomena such as boundary layers or near‐singularities. Enrichment of the basis with additional functions, obtained through analytical or experimental means, can allow for a coarser mesh and more accurate solution. We introduce an enrichment scheme in which an interaction or ‘bridging’ scale term is used to separate the basis formed by the enrichment functions from the original set of basis functions, in effect making the enrichment hierarchical. This separation of scales allows the simple application of essential boundary conditions. It also allows a quantification of the effects of the enrichment, leading to strategies for error estimation and control of the stiffness matrix condition number. We also find that this formulation allows for the simple application of essential boundary conditions for mesh‐free shape functions, which are notoriously problematic. We find that for multiple dimensions, care must be taken to derive a weak form which is truly consistent with the strong form on the essential boundary. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

    

Julie Foertsch  Gregory Moses  John Strikwerda  Mike Litzkow 《工程教育杂志》2002,91(3):267-274

A new online streaming video and multi‐media application called eTEACH, http:eTEACH.engr.wisc.edu was used to reform a large, lecture‐based computer science course for engineering majors. In‐class lectures were replaced with videotaped lectures and other materials that students viewed on the Internet on their own schedule, making it possible to use the live class periods for small, team problem‐solving sessions facilitated by the professors and a teaching assistant. By using the eTEACH application to transform course lectures into “homework” and free up the face‐to‐face class time for working on problems that were similar to homework assignments, the professors effectively reversed the lecture and homework paradigm of a typical large lecture course. A thorough course evaluation over two semesters showed that students who took the online lecture version of the course gave significantly higher ratings to all aspects of the course, including lecture usefulness, professor responsiveness, the course overall, and the instructor. Although a few students missed having the opportunity to ask questions during lectures, about two‐thirds of the 531 students surveyed felt it was easier to take notes and understand the lectures presented via eTEACH than it would have been while attending the same lecture live, and 78% of students appreciated the ability to view and review course lectures on their own schedule.  相似文献   

    

Gregory KD  Hackmeyer P  Gold L  Johnson AI  Platt LD 《The Joint Commission journal on quality improvement》1999,25(12):619-629

BACKGROUND: In 1994 a five-year prospective observational study (including 38,541 singleton live-born deliveries) based on maternal and neonatal hospital administrative discharge data for DRGs 370-375 was launched at Cedars Sinai Medical Center (CSMC) in Los Angeles. In 1993 a cesarean section (C-section) reduction task force was first convened and several interventions were conducted and monitored during a two-year period. In 1995 CSMC joined the Institute for Healthcare Improvement's (IHI's) national collaborative on lowering C-section rates. RESULTS: The first intervention involved physician education (grand rounds) and occurred during the preintervention baseline period. Providing physician-specific data had been implemented before participation in the IHI collaborative. Two other interventions were implemented before the collaborative versus 13 interventions after. The C-section rate decreased from 26.0% in the baseline period in 1993 to 20.5% in 1997, a 21.2% reduction. During the postintervention period, the C-section rate increased to 23.5%. There was no statistically or clinically significant increase in clavicular fractures, brachial plexus injuries, or cerebral hemorrhage in the four study years, compared to the baseline period. DISCUSSION: It is possible to safely reduce C-section delivery rates. Activities are now under way to involve additional private physician leaders in the continuous quality improvement effort. Although the small increase in the C-section rate during the postintervention period may represent statistical variation, and in itself may not be clinically significant, it supports the thesis that ongoing, continuous organizational support is required to achieve and maintain gains.  相似文献   

    

Gregory V. Nelson 《Engineering Management Journal; EMJ》2013,25(3):39-44

ABSTRACT

After several years of applying the Quality Improvement Process to R&D at the R.L. Mitchell Technical Center of Hoechst Celanese Corporation, it is useful to recap the experience to suggest where we have been and what sort of hurdles had to be overcome. Our experience may be useful to others who are involved in implementing quality programs in their own organizations. Their experience may be similar so far, and our experience may suggest what to expect. Our experience was superimposed upon substantial cultural changes in the corporation as it merged with American Hoechst to begin to develop a new corporate culture. We have found that under the umbrella of the corporate values were found not only quality, but also innovation and the management of meaningful change.  相似文献