272 research outputs found
Mixed integer programming in production planning with backlogging and setup carryover : modeling and algorithms
This paper proposes a mixed integer programming formulation for modeling the capacitated multi-level lot sizing problem with both backlogging and setup carryover. Based on the model formulation, a progressive time-oriented decomposition heuristic framework is then proposed, where improvement and construction heuristics are effectively combined, therefore efficiently avoiding the weaknesses associated with the one-time decisions made by other classical time-oriented decomposition algorithms. Computational results show that the proposed optimization framework provides competitive solutions within a reasonable time
Long-term research challenges in wind energy – a research agenda by the European Academy of Wind Energy
The European Academy of Wind Energy (eawe), representing universities and institutes with a significant wind energy programme in 14 countries, has discussed the long-term research challenges in wind energy. In contrast to research agendas addressing short- to medium-term research activities, this eawe document takes a longer-term perspective, addressing the scientific knowledge base that is required to develop wind energy beyond the applications of today and tomorrow. In other words, this long-term research agenda is driven by problems and curiosity, addressing basic research and fundamental knowledge in 11 research areas, ranging from physics and design to environmental and societal aspects. Because of the very nature of this initiative, this document does not intend to be permanent or complete. It shows the vision of the experts of the eawe, but other views may be possible. We sincerely hope that it will spur an even more intensive discussion worldwide within the wind energy community
SUSTAINABLE DEVELOPMENT AND THE PROCESS OF JUSTIFYING CHOICES IN A CONTROVERSIAL UNIVERSE
All in all, neither the path of the generic principle nor that of the reduction to existing principles would appear to be fully satisfactory as the basis for establishing the legitimacy of sustainable development or as a way of making sustainability a principle of legitimacy by its own. We should probably resign ourselves to seeing in this idea a composite construction, still striving towards the formation of a new "superior common principle", without this principle yet being able to be completely clarified and validated. What we have here is an example of the sort of "compromise" described by Boltanski and Thévenot (1991, p.338): "In the compromise, the participants abandon the idea of clarifying the principle of their agreement but endeavour to maintain a frame of mind aiming at the common good." If we want to consolidate the compromise developing around sustainability, it would be well advised to seek the support of tests using well-formed objects. To this end, steps should be taken to move the emphasis away from long-term and unknowable sustainability requirements and closer to secondbest criteria focused on the transitional developments and possible risks of intentional human action, the ways of managing the linking of the different temporalities in play -- as regards the biophysical phenomena, their understanding and the main worlds of legitimacy (Godard, 1992) -- and the introduction of deliberation within the present generations as to what they feel best describes their identity, those things they would like to pass on
Inherited susceptibility to bleomycin-induced chromatid breaks in cultured peripheral blood lymphocytes
Background: Susceptibility to bleomycin-induced chromatid breaks in cultured peripheral blood lymphocytes may reflect the way a person deals with carcinogenic challenges. This susceptibility (also referred to as mutagen sensitivity) has been found to be increased in patients with environmentally related cancers, including cancers of the head and neck, lung, and colon, and, in combination with carcinogenic exposure, this susceptibility can greatly influence cancer risk. The purpose of this study was to assess the heritability of mutagen sensitivity. Methods: Heritability was determined by use of a maximum likelihood method that employed the FISHER package of pedigree analysis. Bleomycin-induced breaks per cell values for 135 healthy volunteers without cancer were determined. These individuals were from 53 different pedigrees and included 25 monozygotic twin pairs (n = 50), 14 pairs of dizygotes (twin pairs and siblings, n = 28), and 14 families selected on the basis of a first-degree relative who was successfully treated for head and neck cancer and who had no sign of recurrence for at least 1 year. All data were analyzed simultaneously, and different models of familial resemblance were fitted to the data. All P values are two-sided. Results: Our results showed no evidence for the influence of a shared family environment on bleomycin-induced chromatid breaks. Genetic influences, however, were statistically significant (P = .036) and accounted for 75% of the total variance. Conclusions: The high heritability estimate of the susceptibility to bleomycin-induced chromatid breaks indicates a clear genetic basis. The findings of this study support the notion that a common genetic susceptibility to DNA damage - and thereby a susceptibility to cancer - may exist in the general population
Multiple carbon accounting to support just and effective climate policies
Negotiating reductions in greenhouse gas emission involves the allocation of emissions and of emission reductions to specific agents, and notably, within the current UN framework, to associated countries. As production takes place in supply chains,increasingly extending over several countries, there are various options available in which emissions originating from one and the same activity may be attributed to different agents along the supply chain and thus to different countries. In this way, several distinct types of national carbon accounts can be constructed. We argue that these accounts will typically differ in the information they provide to individual countries on the effects their actions have on global emissions; and they may also, to varying degrees, prove useful in supporting the pursuit of an effective and just climate policy. None of the accounting systems, however, prove 'best' in achieving these aims under real-world circumstances; we thus suggest compiling reliable data to aid in the consistent calculation of multiple carbon accounts on a global level
Interaction of Co(II), Ni(II) and Cu(II) with dibenzo-substituted macrocyclic ligands incorporating both symmetrically and unsymmetrically arranged N, O and S donors
The synthesis and characterisation of four 17-membered, dibenzo-substituted macrocyclic ligands incorporating unsymmetrical arrangements of their N3S2, N3O2 and N3OS (two ligands) donor atoms are described; these rings complete the matrix of related macrocyclic systems incorporating both symmetric and unsymmetric donor sets reported previously. The X-ray structures of three of the new macrocycles are reported. In two of the Cu(II) structures only three of the possible five donor atoms present in the corresponding macrocyclic ligand bind to the Cu(II) site, whereas all five donors are coordinated in each of the remaining complexes. The interaction of Co(II), Ni(II) and Cu(II) with the unsymmetric macrocycle series has been investigated by potentiometric (pH) titration in 95% methanol; X-ray structures of two nickel and three copper complexes of these ligands, each exhibiting 1 : 1 (M :L) ratios, have been obtained. The results are discussed in the context of previous results for these metals with the analogous 17-membered ring systems incorporating symmetrical arrangements of their donor atoms, with emphasis being given to both the influence of the donor atom set, as well as the donor atom sequence, on the nature of the resulting complexes
Partial costs of global climate change adaptation for the supply of raw industrial and municipal water: a methodology and application
Despite growing recognition of the importance of climate change adaptation, few global estimates of the costs involved are available for the water supply sector. We present a methodology for estimating partial global and regional adaptation costs for raw industrial and domestic water supply, for a limited number of adaptation strategies, and apply the method using results of two climate models. In this paper, adaptation costs are defined as those for providing enough raw water to meet future industrial and municipal water demand, based on country-level demand projections to 2050. We first estimate costs for a baseline scenario excluding climate change, and then additional climate change adaptation costs. Increased demand is assumed to be met through a combination of increased reservoir yield and alternative backstop measures. Under such controversial measures, we project global adaptation costs of 73 bn p.a.), which supports the notion of mainstreaming climate change adaptation into broader policy aims. The method provides a tool for estimating broad costs at the global and regional scale; such information is of key importance in international negotiations. © 2010 IOP Publishing Ltd
Ketahanan Sumberdaya Genetik Jagung Sulawesi Tenggara terhadap Cekaman Kekeringan pada Berbagai Fase Vegetatif
Maize crops experiencing water stress can experience cell damage, loss of turgor, closed stomata, plant leaf roll then wilt. Germination and vegetative growth are thought to be a very sensitive phases in relation to the availability of water, because it can influence subsequent growth processes. This study aimed to determine the potential tolerance of Southeast Sulawesi\u27s maize genotypes to drought stress at different vegetative growth phases. This study was based on completely randomized design (CRD) with factorial pattern consisting of two factors: the first factor composed of 9 local maize genotypes of Southeast Sulawesi and 1 national variety (cv. Arjuna), while the second factor was drought stress at different vegetative growth phases, consisting of four levels ie: C0 = plants irrigated with 100 % water availability during the growth phase, C1 = Stress for 5 days , at 21-26 days old (vegetative phase), C2 = Stress for 5 days starting at panicle emergence (early flowering stage), and C3 = Stress for 5 days starting 2 weeks after silking. Research results showed that Genotype (G) treatment significantly influenced all observed growth variables (at age 21 and 42 days after planting, DAP), except for the variable of number of leaf, age 21 DAP. However, water stress treatment (C) only significantly affected plant height variable, at the age of 42 DAP. In general, G6 and G7 genotypes tended to have a higher crop and trunk diameter than the other genotypes. Contrary, G3 genotype tended to have shorter crop and smaller stem diameter than the other genotypes. There are indications that the drought stress treatment (C) significantly inhibited the growth of maize crops
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