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381.
Stefano Tarantola Michela Nardo Michaela Saisana Debora Gatelli 《Reliability Engineering & System Safety》2006,91(10-11):1135-1141
In this paper we propose and test a generalisation of the method originally proposed by Sobol’, and recently extended by Saltelli, to estimate the first-order and total effect sensitivity indices. Exploiting the symmetries and the dualities of the formulas, we obtain additional estimates of first-order and total indices at no extra computational cost. We test the technique on a case study involving the construction of a composite indicator of e-business readiness, which is part of the initiative “e-Readiness of European enterprises” of the European Commission “e-Europe 2005” action plan. The method is used to assess the contribution of uncertainties in (a) the weights of the component indicators and (b) the imputation of missing data on the composite indicator values for several European countries. 相似文献
382.
Khurram Shahzad Karl-Heinz Kettl Michaela Titz Martin Koller Hans Schnitzer Michael Narodoslawsky 《Clean Technologies and Environmental Policy》2013,15(3):525-536
Realizing a sustainable development of our planet requires a reduction of waste production, harmful emissions, and higher energy efficiency as well as utilization of renewable energy sources. One pathway to this end is the design of sustainable biorefinery concepts. Utilizing waste streams as raw material is gaining great importance in this respect. This reduces environmental burden and may at the same time contribute to economic performance of biorefineries. This paper investigates the utilization of slaughtering waste to produce biodegradable polyesters, polyhydroxyalkanoates (PHA), via bioconversion. PHA are the target product while production of high quality biodiesel along with meat and bone meal (MBM) as by-products improves the economic performance of the process. The paper focuses on ecological comparison of different production scenarios and the effect of geographical location of production plants taking different energy production technologies and resources into account; ecological footprint evaluation using Sustainable Process Index methodology was applied. Keeping in mind that the carbon source for PHA production is produced from waste by energy intensive rendering process, the effect of available energy mixes in different countries becomes significant. Ecological footprint results from the current study show a bandwidth from 372,950 to 956,060 m2/t PHA production, depending on the energy mix used in the process which is compared to 2,508,409 m2/t for low density polyethylene. 相似文献
383.
Michaela Aloni 《Scientometrics》1985,8(5-6):279-300
This review discusses studies of informal communication of scientific and technical information published in the American management literature between 1976 and 1982. While investigated formerly by information scientists, the subject has been mentioned only infrequently in the literature and abstracts of information science in recent years. Management scientists view the informal information transfer as a special type of organizational communication. Among the papers reviewed, special attention is accorded to the publications byTushman who has extended and developedAllen's approach. The implications of the insights gained for the information worker and information scientist are discussed in the conclusions. 相似文献
384.
Urpí-Sardà M Jáuregui O Lamuela-Raventós RM Jaeger W Miksits M Covas MI Andres-Lacueva C 《Analytical chemistry》2005,77(10):3149-3155
In this paper, a sensitive, precise, and selective analytical method has been developed for the identification and quantification of resveratrol metabolites in human low-density lipoprotein (LDL) after moderate consumption of red wine, using high-performance liquid chromatography electrospray in tandem mass spectrometry (LC-ESI-MS/MS). From different extraction procedures tested, solid-phase extraction was selected to minimize matrix effects reaching the highest sensitivity. Standard calibration curves prepared in human LDL for trans-resveratrol were linear over a range of 0.44-438.59 pmol/mL. The accuracy and interassay precision of this LC-MS/MS assay for resveratrol showed a coefficient of variation of <6.0%. The method allows detection and quantification limits for resveratrol in LDL at 0.15 and 0.44 pmol/mL, respectively. Results to date indicate that resveratrol metabolites were incorporated into LDL after a moderate intake of red wine. The metabolites identified in LDL were trans-resveratrol-3-O-glucuronide, cis-resveratrol-3-O-glucuronide, and cis-resveratrol-3-O-glucoside, as well as free trans-resveratrol. To our knowledge, it is the first time that a polyphenol from red wine, specifically resveratrol, has been identified in human LDL after moderate intake of red wine. Furthermore, these findings suggest that these compounds may deliver their antioxidant effect to LDL. 相似文献
385.
MM Champ C Molis B Flourié F Bornet P Pellier P Colonna JP Galmiche JC Rambaud 《Canadian Metallurgical Quarterly》1998,68(3):705-710
Primary adenocarcinoma of sweat glands is a rare tumor; approximately 220 cases have been reported in the last 30 years. We reviewed the charts of patients with primary diagnosis of this tumor treated at the Mayo Clinic between 1935 and 1995. We included only cases with initial histology slides available for re-examination. Tumors were classified into five recognizable histologic patterns (solid, ductal, mucinous, microcystic adnexal, and adenocystic carcinoma) and graded by the Broder system. Statistical analysis consisted of Kaplan-Meier product limit method and Cox multiple regression test. In total, 55 patients were identified, and age ranged from 13 to 85 years (mean 59 years). Thirty-six patients (65 percent) presented to the Mayo Clinic for initial treatment; all except one had disease limited to the primary site. Microcystic adnexal carcinoma was the most frequent type, and more than 50 percent were grade 2 tumors. Among these 36 patients, 4 had some type of recurrence. Patients who developed metastasis had a high-grade tumor in the initial biopsy. Nineteen patients were referred with recurrence; 13 had local recurrence, 4 had regional diseases, and 2 had distant metastases. The histologic distribution showed 47 percent solid tumors, and 37 percent of them were grade 3. Multiple regression analysis did not show a difference in recurrence or survival when gender, age, tumor location, or histologic pattern was evaluated. In addition, there was no difference in the outcome between wide surgical resection and micrographic surgery. The only predictive factor for distant metastases and/or death (p < 0.003) was histologic grade. Overall 10-year survival rate was 86 and 60 percent for primary and referred patients, respectively. We conclude that histologic diagnosis of sweat gland carcinoma must be complemented by clinical examination to evaluate metastases. Clinical behavior depends on the histologic type of tumor, degree of differentiation, and clinical stage. On recurrence, the likelihood of further recurrences and mortality increases dramatically. Aggressive initial local ablation with tumor-free margins is recommended. In high-grade tumors, prophylactic regional lymph node dissection may further characterize tumor aggressiveness and may justify adjuvant radiotherapy as part of the primary treatment. 相似文献
386.
Modern civilization moves ahead with strong economical growth. Using a large number of new technologies and new machines in working procedures brings a proportional growth of noise and vibration. Noise and vibration have become an essential part of active safety measures because they are endangering the health of the employee as well as the public. Preventive solutions are ensured in new legislation and standards too. They facilitate high levels of unification of safety requirements for machines as well as the working environment from the acoustics point of view. © 2012 Wiley Periodicals, Inc. 相似文献
387.
Tracy Erin N.; Bucchianeri Michaela M.; Rodolfa Emil R. 《Canadian Metallurgical Quarterly》2011,5(2):97
Inconsistent training requirements across predoctoral internships have problematic implications for psychologists seeking licensure and for the profession as a whole. This investigation is an 11-year follow-up to a previous study (Bartle & Rodolfa, 1999) that explored the variation in hours accrued across predoctoral internship programs. The current study examined the total number of supervised training hours provided by internships and the methods utilized by training directors to calculate these hours. The total number of supervised hours reported by training directors ranged from 1,840 to 2,080, with 58.2% calculating hours by approximation, rounding off, or estimation. As training directors reported more total hours, they were increasingly likely to include holiday, vacation, and sick leave. Recommendations for state licensing boards and internship training programs are provided, including a national licensure requirement of 1,800 hours accrued during internship. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
388.
Riediger Michaela; Wrzus Cornelia; Schmiedek Florian; Wagner Gert G.; Lindenberger Ulman 《Canadian Metallurgical Quarterly》2011,11(3):656
Hedonism, or wanting to feel good, is central to human motivation. At times, however, people also seek to maintain or enhance negative affect or to dampen positive affect, and this can be instrumental for the later attainment of their goals. Here, we investigate the assumption that such contra-hedonic orientation is cognitively more demanding than prohedonic orientation, above and beyond the effects of momentary affective experience. We provided 378 participants with mobile phones that they carried with them for 3 weeks while pursuing their daily routines. The phones prompted participants at least 54 times to report their current affect-regulation orientation and to work on two trials of a cognitively demanding working memory task. As expected, contra-hedonic orientation was substantially less prevalent than prohedonic orientation. It was reported in 15% of the measurement occasions. Participants who reported on average more contra-hedonic orientation showed lower average working memory performance throughout the study interval. Further, controlling for the effects of accompanying affective experiences, momentary occurrences of contra-hedonic orientation were associated with temporary declines in working memory performance within individuals, and this could neither be explained by lacking task compliance nor by other characteristics of the individual or the situation. Prohedonic orientation showed a considerably smaller association with working memory performance. These findings are consistent with the view that contra-hedonic orientation is accompanied by momentarily more diminished cognitive resources than is prohedonic orientation. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
389.
Corning Alexandra F.; Malofeeva Elena V.; Bucchianeri Michaela M. 《Canadian Metallurgical Quarterly》2007,44(2):193
Discrepancies between clients and therapists in their perceptions of the severity of the client's presenting problem were tested for their utility in predicting both premature and mutual termination. Eight problem types were examined, and analyses were conducted within a survival analysis framework. Across the majority of problem types, results indicated that greater discrepancies between clients and therapists lowered the odds of mutual termination; however, greater discrepancies did not in turn increase the odds of premature termination. Interaction tests of client-therapist discrepancy with a variable that changes over time, accruing number of sessions, offer some qualifications. In particular, in the case of two problem types--depression and family-of-origin--when large discrepancies occurred, the likelihood of premature termination maintained at an equal rate throughout treatment, whereas when discrepancies were moderate or absent, the likelihood of premature termination diminished. Implications for clinicians and researchers point to enhancement of the therapeutic alliance as a means of reducing the probability of premature termination and increasing the probability of mutual termination. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
390.
Software architectures such as plug-in and service-oriented architectures enable developers to build extensible software products, whose functionality can be enriched by adding or configuring components. A well-known example of such an architecture is Eclipse, best known for its use to create a series of extensible IDEs. Although such architectures give users and developers a great deal of flexibility to create new products, the complexity of the built systems increases. In order to manage this complexity developers use extensive automated test suites. Unfortunately, current testing tools offer little insight in which of the many possible combinations of components and components configurations are actually tested. The goal of this paper is to remedy this problem. To that end, we interview 25 professional developers on the problems they experience in test suite understanding for plug-in architectures. The findings have been incorporated in five architectural views that provide an extensibility perspective on plug-in-based systems and their test suites. The views combine static and dynamic information on plug-in dependencies, extension initialization, extension and service usage, and the test suites. The views have been implemented in ETSE, the Eclipse Plug-in Test Suite Exploration tool. We evaluate the proposed views by analyzing eGit, Mylyn, and a Mylyn connector. 相似文献