Application of fuzzy set and Dempster-Shafer theory to organic geochemistry interpretation

An application of fuzzy sets and Dempster Shafter Theory (DST) in modeling the interpretational process of organic geochemistry data for predicting the level of maturities of oil and source rock samples is presented. This was accomplished by (1) representing linguistic imprecision and imprecision associated with experience by a fuzzy set theory, (2) capturing the probabilistic nature of imperfect evidences by a DST, and (3) combining multiple evidences by utilizing John Yen's generalized Dempster-Shafter Theory (GDST), which allows DST to deal with fuzzy information. The current prototype provides collective beliefs on the predicted levels of maturity by combining multiple evidences through GDST's rule of combination

Permafrost temperatures and active layer thickness in Svalbard during 2017/2018 (PermaSval)

This report follows up on the report published in the SESS Report 2018 (Christiansen et al. 2019). Since 2018, the Norwegian Environment Agency has released the Climate in Svalbard 2100 report summarizing observed trends in permafrost conditions over the period of field measurements and a forecast for the future, based on recent climate and permafrost modelling (Hanssen-Bauer et al. 2019). It is well established that the terrestrial cryosphere in Svalbard has changed since modern permafrost monitoring efforts began in the late 1990s. In central Svalbard in the Adventdalen area, ground temperatures have risen by as much as 0.15°C per year (10 m depth) and the thickness of the seasonally-unfrozen active layer increased by 0.6 cm per year since 2000 in sediments and 1.6 cm/year in bedrock (Hanssen-Bauer et al. 2019), while in Ny-Ålesund ground temperatures increased by 0.18°C/year and the thickness of active layer increased by 5 cm/year (Boike et al. 2018). Modern monitoring techniques mean that it is relatively easy to quantify permafrost change in terms of temperature. The visible effects of warming permafrost are, however, more ambiguous. A prolonged thaw season is anticipated to result in a thicker active layer, and increased rainfall intensity can result in more frequent landslides. The strength of frozen soil decreases when warming and permafrost change may expectedly result in infrastructure problems in cases where climate change was not considered during the initial design. The aims of this part of the State of Environmental Science in Svalbard reporting are to: (1) provide an overview of permafrost data collected during the 2017-2018 hydrological year (1 September 2017 – 31 August 2018), (2) contrast these results with the 2016-2017 hydrological year as presented in Christiansen et al. (2019), (3) summarise developments in permafrost monitoring in Svalbard, and (4) provide recommendations for future permafrost investigations. Understanding the spatial distribution of permafrost conditions is critical to predicting geomorphological change and understanding the variability in climate impacts. 2371

Halocarbon ozone depletion and global warming potentials

Concern over the global environmental consequences of fully halogenated chlorofluorocarbons (CFCs) has created a need to determine the potential impacts of other halogenated organic compounds on stratospheric ozone and climate. The CFCs, which do not contain an H atom, are not oxidized or photolyzed in the troposphere. These compounds are transported into the stratosphere where they decompose and can lead to chlorine catalyzed ozone depletion. The hydrochlorofluorocarbons (HCFCs or HFCs), in particular those proposed as substitutes for CFCs, contain at least one hydrogen atom in the molecule, which confers on these compounds a much greater sensitivity toward oxidation by hydroxyl radicals in the troposphere, resulting in much shorter atmospheric lifetimes than CFCs, and consequently lower potential for depleting ozone. The available information is reviewed which relates to the lifetime of these compounds (HCFCs and HFCs) in the troposphere, and up-to-date assessments are reported of the potential relative effects of CFCs, HCFCs, HFCs, and halons on stratospheric ozone and global climate (through 'greenhouse' global warming)

Radiative forcing in the 21st century due to ozone changes in the troposphere and the lower stratosphere

Radiative forcing due to changes in ozone is expected for the 21st century. An assessment on changes in the tropospheric oxidative state through a model intercomparison ("OxComp'') was conducted for the IPCC Third Assessment Report (IPCC-TAR). OxComp estimated tropospheric changes in ozone and other oxidants during the 21st century based on the "SRES'' A2p emission scenario. In this study we analyze the results of 11 chemical transport models (CTMs) that participated in OxComp and use them as input for detailed radiative forcing calculations. We also address future ozone recovery in the lower stratosphere and its impact on radiative forcing by applying two models that calculate both tropospheric and stratospheric changes. The results of OxComp suggest an increase in global-mean tropospheric ozone between 11.4 and 20.5 DU for the 21st century, representing the model uncertainty range for the A2p scenario. As the A2p scenario constitutes the worst case proposed in IPCC-TAR we consider these results as an upper estimate. The radiative transfer model yields a positive radiative forcing ranging from 0.40 to 0.78 W m(-2) on a global and annual average. The lower stratosphere contributes an additional 7.5-9.3 DU to the calculated increase in the ozone column, increasing radiative forcing by 0.15-0.17 W m(-2). The modeled radiative forcing depends on the height distribution and geographical pattern of predicted ozone changes and shows a distinct seasonal variation. Despite the large variations between the 11 participating models, the calculated range for normalized radiative forcing is within 25%, indicating the ability to scale radiative forcing to global-mean ozone column change

Structural and Functional Characterization of a Lytic Polysaccharide Monooxygenase with Broad Substrate Specificity

The recently discovered lytic polysaccharide monooxygenases (LPMOs) carry out oxidative cleavage of polysaccharides and are of major importance for efficient processing of biomass. NcLPMO9C from Neurospora crassa acts both on cellulose and on non-cellulose β-glucans, including cellodextrins and xyloglucan. The crystal structure of the catalytic domain of NcLPMO9C revealed an extended, highly polar substrate-binding surface well suited to interact with a variety of sugar substrates. The ability of NcLPMO9C to act on soluble substrates was exploited to study enzyme-substrate interactions. EPR studies demonstrated that the Cu2+ center environment is altered upon substrate binding, whereas isothermal titration calorimetry studies revealed binding affinities in the low micromolar range for polymeric substrates that are due in part to the presence of a carbohydrate-binding module (CBM1). Importantly, the novel structure of NcLPMO9C enabled a comparative study, revealing that the oxidative regioselectivity of LPMO9s (C1, C4, or both) correlates with distinct structural features of the copper coordination sphere. In strictly C1-oxidizing LPMO9s, access to the solvent-facing axial coordination position is restricted by a conserved tyrosine residue, whereas access to this same position seems unrestricted in C4-oxidizing LPMO9s. LPMO9s known to produce a mixture of C1- and C4-oxidized products show an intermediate situation

Photochemical modelling in the Po basin with focus on formaldehyde and ozone

As part of the EU project FORMAT ( Formaldehyde as a Tracer of Oxidation in the Troposphere), a field campaign was carried out in the vicinity of Milan during the summer of 2002. Results from a 3-D regional chemical transport model (NILU RCTM) were used to interpret the observations focusing primarily on HCHO and ozone. The performance of the model was assessed by comparing model results with ground based and aircraft measurements. The model results show good agreement with surface measurements, and the model is able to reproduce the photochemical episodes during fair weather days. The comparison indicates that the model can represent well the HCHO concentrations as well as their temporal and spatial variability. The relationship between HCHO and (O-3 x H2O) was used to validate the model ability to predict the HCHO concentrations. Further analysis revealed the importance of the representativeness of different instruments: in-situ concentrations might be locally enhanced by emissions, while long path measurements over a forest can be influenced by rapid formation of HCHO from isoprene. The model is able to capture the plume from the city of Milan and the modelled levels agree generally well with the aircraft measurements, although the wind fields used in the model can lead to a displacement of the ozone plume. During the campaign period, O3 levels were seldom higher than 80 ppb, the peak surface ozone maxima reached 90 ppb. Those relatively low values can be explained by low emissions during the August vacation and unstable weather conditions in this period. The modelled Delta O-3/Delta NOz slope at Alzate of 5.1 agrees well with the measured slope of 4.9

An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach allows for a very close comparison with observations and fully accounts for the specific meteorological conditions during the measurement flights. This is important considering the often limited availability and representativity of such trace gas measurements. A new extensive database including all major research and commercial aircraft measurements between 1995 and 1998, as well as ozone soundings, was established specifically to support this type of direct comparison. Quantitative methods were applied to judge model performance including the calculation of average concentration biases and the visualization of correlations and RMS errors in the form of so-called Taylor diagrams. We present the general concepts applied, the structure and content of the database, and an overall analysis of model skills over four distinct regions. These regions were selected to represent various atmospheric conditions and to cover large geographical domains such that sufficient observations are available for comparison. The comparison of model results with the observations revealed specific problems for each individual model. This study suggests the further improvements needed and serves as a benchmark for re-evaluations of such improvements. In general all models show deficiencies with respect to both mean concentrations and vertical gradients of important trace gases. These include ozone, CO and NOx at the tropopause. Too strong two-way mixing across the tropopause is suggested to be the main reason for differences between simulated and observed CO and ozone values. The generally poor correlations between simulated and measured NOx values suggest that in particular the NOx input by lightning and the convective transport from the polluted boundary layer are still not well described by current parameterizations, which may lead to significant differences in the spatial and seasonal distribution of NOx in the models. Simulated OH concentrations, on the other hand, were found to be in surprisingly good agreement with measured values

Analysis and quantification of the diversities of aerosol life cycles within AeroCom

Simulation results of global aerosol models have been assembled in the framework of the AeroCom intercomparison exercise. In this paper, we analyze the life cycles of dust, sea salt, sulfate, black carbon and particulate organic matter as simulated by sixteen global aerosol models. The diversities among the models for the sources and sinks, burdens, particle sizes, water uptakes, and spatial dispersals have been established. These diversities have large consequences for the calculated radiative forcing and the aerosol concentrations at the surface. The AeroCom all-models-average emissions are dominated by the mass of sea salt (SS), followed by dust (DU), sulfate (SO_4), particulate organic matter (POM), and finally black carbon (BC). Interactive parameterizations of the emissions and contrasting particles sizes of SS and DU lead generally to higher diversities of these species, and for total aerosol. The lower diversity of the emissions of the fine aerosols, BC, POM, and SO_4, is due to the use of similar emission inventories, and does therefore not necessarily indicate a better understanding of their sources. The diversity of SO_4-sources is mainly caused by the disagreement on depositional loss of precursor gases and on chemical production. The diversities of the emissions are passed on to the burdens, but the latter are also strongly affected by the model-specific treatments of transport and aerosol processes. The burdens of dry masses decrease from largest to smallest: DU, SS, SO_4, POM, and BC. The all-models-average residence time is shortest for SS with about half a day, followed by S_O4 and DU with four days, and POM and BC with six and seven days, respectively. The wet deposition rate is controlled by the solubility and increases from DU, BC, POM to SO_4 and SS. It is the dominant sink for SO_4, BC, and POM, and contributes about one third to the total removal rate coefficients of SS and DU species. For SS and DU we find high diversities for the removal rate coefficients and deposition pathways. Models do neither agree on the split between wet and dry deposition, nor on that between sedimentation and turbulent dry Deposition. We diagnose an extremely high diversity for the uptake of ambient water vapor that influences the particle size and thus the sink rate coefficients. Furthermore, we find little agreement among the model results for the partitioning of wet removal into scavenging by convective and stratiform rain. Large differences exist for aerosol dispersal both in the vertical and in the horizontal direction. In some models, a minimum of total aerosol concentration is simulated at the surface. Aerosol dispersal is most pronounced for SO4 and BC and lowest for SS. Diversities are higher for meridional than for vertical dispersal, they are similar for a given species and highest for SS and DU. For these two components we do not find a correlation between vertical and meridional aerosol dispersal. In addition the degree of dispersals of SS and DU is not related to their residence times. SO_4, BC, and POM, however, show increased meridional dispersal in models with larger vertical dispersal, and dispersal is larger for longer simulated residence times

Successful new product development by optimizing development process effectiveness in highly regulated sectors: the case of the Spanish medical devices sector

Rapid development and commercialization of new products is of vital importance for small and medium sized enterprises (SME) in regulated sectors. Due to strict regulations, competitive advantage can hardly be achieved through the effectiveness of product concepts only. If an SME in a highly regulated sector wants to excell in new product development (NPD) performance, the company should focus on the flexibility, speed, and productivity of its NPD function: i.e. the development process effectiveness. Our main research goals are first to explore if SMEs should focus on their their development process effectiveness rather than on their product concept effectiveness to achieve high NPD performance; and second, to explore whether a shared pattern in the organization of the NPD function can be recognized to affect NPD performance positively. The medical devices sector in Spain is used as an example of a\ud highly regulated sector. A structured survey among 11 SMEs, of which 2 were studied also as in in-depth case studies, led to the following results. First of all, indeed the companies in the dataset which focused on the effectiveness of their development process, stood out in NPD performance. Further, the higher performing companies did have a number of commonalities in the organisation of their NPD function: 1) The majority of the higher performing firms had an NPD strategy characterized by a predominantly incremental project portfolio.\ud 2) a) Successful firms with an incremental project portfolio combined this with a functional team structure b) Successful firms with a radical project portfolio combined this with a heavyweight or autonomous team structure.\ud 3) A negative reciprocal relationship exists between formalization of the NPD processes and the climate of the NPD function, in that a formalized NPD process and an innovative climate do not seem to reinforce each other. Innovative climate combined with an informal NPD process does however contribute positively to NPD performance. This effect was stronger in combination with a radical project portfolio. The highest NPD performance was measured for companies focusing mainly on incremental innovation. It is argued that in highly regulated sectors, companies with an incremental product portfolio would benefit from employing a functional structure. Those companies who choose for a more radical project portfolio in highly regulated sectors should be aware\ud that they are likely to excell only in the longer term by focusing on strategic flexibility. In their NPD organization, they might be well advised to combine informal innovation processes with an innovative climate