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41.
For governments and for manufacturing companies, global warming, rising energy prices, and customers’ increasing ecological awareness have pushed energy efficient manufacturing to the top of the agenda. Governments and companies are both striving to identify the most effective measures to increase energy efficiency in manufacturing processes. Based on results of a recent EU-funded roadmapping project, this paper highlights the needs of industrial companies for integrating energy efficiency performance in production management. First, it analyses concepts and tools for measurement, control and improvement of energy efficiency in production management proposed in literature. Second, the paper outlines that ICT tools and standardization are important enablers for energy efficient manufacturing. Third, industrial needs in these areas are presented based on expert interviews. The industrial needs thus identified are contrasted with concepts proposed in literature to point out the implementation gaps between practice and theory. The paper demonstrates that there exists a gap between the solutions available and the actual implementation in industrial companies. It concludes by deriving requirements for energy management in production that future collaborative research projects should address.  相似文献   
42.
In their recent study, Hilbeck et al. (2012) report that Cry1Ab causes lethal effects on larvae of the ladybird beetle Adalia bipunctata when fed directly to the predator. Such toxic effects were not previously observed in a direct feeding study conducted by us (álvarez-Alfageme et al. 2011). Because Hilbeck et al. (2012) claim that our study design did not allow us to detect any adverse effects we provide arguments for the value and relevance of our study in this commentary. Furthermore we discuss two additional published studies that have not revealed any direct effects of Cry1Ab on larvae of A. bipunctata and are not mentioned by Hilbeck et al. (2012). One of the studies was conducted in our laboratory under more realistic exposure conditions (álvarez-Alfageme et al. 2011). Feeding A. bipunctata larvae with spider mites reared on Bt maize did not reveal any adverse effects on lethal and sublethal parameters of the predator. This was despite the fact that the larvae had ingested high amounts of biologically-active Cry1Ab protein. Thus, we do not see verified evidence that A. bipunctata larvae are sensitive to Cry1Ab at realistic worst-case exposure concentrations. This, together with the fact that A. bipunctata will be little exposed to Cry1Ab under field conditions, allows us to conclude that the risk of Bt maize to this predator is negligible. Support for this comes from the results of many Bt maize field studies that have not revealed evidence for direct Cry1Ab-effects on non-Lepidoptera species.  相似文献   
43.
Several integrated assessment studies have concluded that future learning about the uncertainties involved in climate change has a considerable effect on welfare but only a small effect on optimal short-term emissions. In other words, learning is important but anticipation of learning is not. We confirm this result in the integrated assessment model “model of investment and technological development” for learning about climate sensitivity and climate damages. If learning about an irreversible threshold is included, though, we show that anticipation can become crucial both in terms of necessary adjustments of pre-learning emissions and resulting welfare gains. We specify conditions on the time of learning and the threshold characteristic, for which this is the case. They can be summarized as a narrow “anticipation window.”  相似文献   
44.
Surface runoff is one of the most important pathways for pesticides to enter surface waters. Mathematical models are employed to characterize its spatio-temporal variability within landscapes, but they must be simple owing to the limited availability and low resolution of data at this scale. This study aimed to validate a simplified spatially-explicit model that is developed for the regional scale to calculate the runoff potential (RP). The RP is a generic indicator of the magnitude of pesticide inputs into streams via runoff. The underlying runoff model considers key environmental factors affecting runoff (precipitation, topography, land use, and soil characteristics), but predicts losses of a generic substance instead of any one pesticide. We predicted and evaluated RP for 20 small streams. RP input data were extracted from governmental databases. Pesticide measurements from a triennial study were used for validation. Measured pesticide concentrations were standardized by the applied mass per catchment and the water solubility of the relevant compounds. The maximum standardized concentration per site and year (runoff loss, RLoss) provided a generalized measure of observed pesticide inputs into the streams. Average RP explained 75% (p < 0.001) of the variance in RLoss. Our results imply that the generic indicator can give an adequate estimate of runoff inputs into small streams, wherever data of similar resolution are available. Therefore, we suggest RP for a first quick and cost-effective location of potential runoff hot spots at the landscape level.  相似文献   
45.
A new analytical method using accelerated solvent extraction was developed for the determination of 10 particle-associated polar and semipolar pesticides. In addition, six deuterated analogues of the target compounds were evaluated as internal standards. The method yielded acceptable accuracy (73–103% recovery) and precision (<25% relative standard deviation) for eight compounds. Using size exclusion chromatography (SEC) as cleanup step resulted in higher recoveries compared to solid phase extraction (SPE) cleanup.

Deuterated standards with 10 or more deuterium atoms performed well as internal standards concerning similar recovery and correlation with the target analytes.

The method was employed to extract particle-associated pesticides from 16 streams located in an area with intense agriculture in France. Acetochlor, pirimicarb, tebuconazole, fenpropidin, -endosulfan and chlorfenvinphos were detected at concentrations up to 1 mg kg−1 dry weight. A comparison with aquatic toxicity data indicated potential risk to the benthic fauna exposed to these concentrations of pirimicarb, -endosulfan and chlorfenvinphos.

We suggest that the method presented here be used for the extraction and quantitation of particle-associated polar pesticides.  相似文献   

46.
Application of microbial hot spots enhances pesticide degradation in soils   总被引:1,自引:0,他引:1  
Through transfer of an active, isoproturon degrading microbial community, pesticide mineralization could be successfully enhanced in various soils under laboratory and outdoor conditions. The microbes, extracted from a soil having high native ability to mineralize this chemical, were established on expanded clay particles and distributed to various soils in the form of microbial "hot spots". Both, diffusion controlled isoproturon mass flow towards these "hot spots" (6microg d(-1)) as well as microbial ability to mineralize the herbicide (approximately 5microg d(-1)) were identified as the main processes enabling a multiple augmentation of the native isoproturon mineralization even in soils with heavy metal contamination. Soil pH-value appears to exert an important effect on the sustainability of this process.  相似文献   
47.
针对传统教与学算法在解决复杂多峰函数优化问题时,具有局部最优且搜索开发能力较差的缺点,提出了一种改进的多学习教与学优化算法,新算法为学员的每一维加入不同的教学因子,设计了基于学员均值比较的教师选择策略和向教师及学员学习的多学习策略。基于多个单峰和多峰函数的仿真结果表明,新算法跟传统的、改进的教与学算法相比,在稳定性、寻优精度和收敛速度方面更具优势。  相似文献   
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