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101.
Radiation fog is an important modifier of atmosphericcompounds in the planetary boundary layer. In vegetated areas effects are especially pronounced due to the enlarged surface area. Besides affectingthe lower boundary of atmospheric models fog acts as amulti-phase reaction chamber leading to acid deposition. Here we present the 1-dimensional radiation fog modelCHEMIFOG_V to simulate regional radiation fogevents. The key feature of the fog model is thedetailed microphysics, where the aerosol/dropletspectrum is describedwith a joint 2-dimensional distribution, but also thedynamics, thermodynamics, and radiative transfer are calculated. Toinvestigate the interaction between fog and the biosphere amulti-layer vegetation module, including a soil module as well as a drydeposition module were coupled. Vegetation influences thedynamics, thermodynamics, and the radiation field of the lowestatmospheric layers. With CHEMIFOG_V, numerical case studieson dry and moist deposition processes on vegetation surfaces wereperformed. Hereby multi-phase chemistry and the processing of aerosolswere considered. The results show that the chemical composition of thedeposited fog droplets is mainly determined by the aerosol composition. Dry deposition fluxes are dependent on the incoming radiation and the leaves' surface conditions with respect to water coverage.Due to chemical aerosol processing and deposition, the aerosol spectrumis significantly modified in the planetary boundary layer. 相似文献
102.
Gerhard Blickle James A. Meurs Andreas Wihler Christian Ewen Andrea Plies Susann Günther 《组织行为杂志》2013,34(8):1145-1164
Caveats concerning the ability of personality to predict job performance have been raised because of seemingly modest criterion‐related validity. The goal of the present research was to test whether narrowing the context via the type of job (i.e., jobs with complex task demands) and adding a social skill‐related moderator (i.e., political skill) would improve performance prediction. Further, along with political skill, the broad factor of personality demonstrated in prior research to have the strongest criterion validity (i.e., conscientiousness) was joined with a narrow construct closely related to openness to experience (i.e., learning approach) in a three‐way interactive prediction of supervisor‐rated task performance. With the employee–supervisor dyads among professionals, but not with the control group of non‐professional employees, task performance was predicted by the three‐way interaction, such that those high on all three received the highest performance ratings. Implications, strengths and limitations, and directions for future research are discussed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
103.
Alfred Benninghoven Fritz Bindzius Detlef Braun Jutta Cramer Rolf Ellegast Udo Flowerday Andreas Genz Thomas von der Heyden Wolfgang Pfeiffer Dagmar Schittly Ralf Schweer Roger Stamm 《International journal of occupational safety and ergonomics》2005,11(4):409-421
Call centre workplaces are in many ways a challenge to occupational health and safety. The occupation itself can be described as an IT information technology-supported, communication-intensive form of work with often unusual working hours and a high rate of part-time employment. Data on the employee turnover as well as absenteeism related to occupational disability is quite contradictory. Occupational safety and its proponents still have to find new ways into the corporate structures and cultures of this relatively new and rapidly growing branch of industry. In a 2-year research and development project, using a holistic approach and under consideration of all the relevant disciplines, call centre workplaces were studied, and organisational measures were developed and field tested by putting them into practice. Practical help was developed for a sustainable strategy for successful and healthy work in call centres. 相似文献
104.
Does the Temporal Resolution of Precipitation Input Influence the Simulated Hydrological Components Employing the SWAT Model? 下载免费PDF全文
Andreas Bauwe Sara Tiedemann Petra Kahle Bernd Lennartz 《Journal of the American Water Resources Association》2017,53(5):997-1007
This study aimed to evaluate the influence of sub‐daily precipitation time steps on model performance and hydrological components by applying the Green and Ampt infiltration method using the Soil and Water Assessment Tool (SWAT). Precipitation was measured at a resolution of 0.1 mm and aggregated to 5‐, 15‐, 30‐, and 60‐min time steps. Daily discharge data over a 10‐year period were used to calibrate and validate the model. Following a global sensitivity analysis, relevant parameters were optimized through an automatic calibration procedure using SWAT‐CUP for each time step. Daily performance statistics were almost equal among all four time steps (NSE ≈ 0.47). Discharge mainly consisted of groundwater flow (55%) and tile flow (42%), in reasonable proportions for the investigated catchment. In conclusion, model outputs were almost identical, showing simulations responded nearly independently of the chosen precipitation time step. This held true for (1) the selection of sensitive parameters, (2) performance statistics, (3) the shape of the hydrographs, and (4) flow components. However, a scenario analysis revealed that the precipitation time step becomes important when saturated hydraulic conductivities are low and curve numbers are high. The study suggests that there is no need in using precipitation time steps <1 h for lowland catchments dominated by soils with a low surface runoff potential if daily flow values are being considered. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series. 相似文献
105.
106.
Per Schubert Nils G. A. Ekelund Thomas H. Beery Christine Wamsler K. Ingemar Jönsson Andreas Roth 《Journal of Environmental Policy & Planning》2018,20(3):298-312
While ecosystem-based planning approaches are increasingly promoted through international and national policies, municipalities are still struggling with translating them into practice. Against this background, this paper aims to increase the knowledge of current advances and possible ways to support the implementation of the ecosystem services (ES) approach at the municipal level. More specifically, we analyze how ES have been integrated into comprehensive planning within the municipality of Malmö in Sweden over the last 60 years, a declared forerunner in local environmental governance. Based on a content analysis of comprehensive plans over the period 1956–2014 and interviews with municipal stakeholders, this paper demonstrates how planning has shifted over time toward a more holistic view of ES and their significance for human well-being and urban sustainability. Both explicit and implicit applications of the ES concept were found in the analyzed comprehensive plans and associated programs and projects. Our study shows how these applications reflect international, national, and local policy changes, and indicates how municipalities can gradually integrate the ES approach into comprehensive planning and facilitate the transition from implicit to more explicit knowledge use. 相似文献
107.
Michael Ahlheim Benchaphun Ekasingh Jirawan Kitchaicharoen Andreas Neef Chapika Sangkapitux 《Journal of Environmental Planning and Management》2010,53(2):163-182
Although contingent valuation is the dominant technique for the valuation of public projects, especially in the environmental sector, the high costs of contingent valuation surveys prevent the use of this method for the assessment of relatively small projects. The reason for this cost problem is that typically only contingent valuation studies which are based on face-to-face interviews are accepted as leading to valid results. Particularly in countries with high wages, face-to-face surveys are extremely costly considering that for a valid contingent valuation study a minimum of 1000 completed face-to-face interviews is required. This paper tries a rehabilitation of mail surveys as low-budget substitutes for costly face-to-face surveys. Based on an empirical contingent valuation study in Northern Thailand, it is shown that the validity of mail surveys can be improved significantly if so-called Citizen Expert Groups are employed for a thorough survey design. 相似文献
108.
Aris Antsaklis George Daskalakis Nikolaos Papantoniou Andreas Mentis Stylianos Michalas 《黑龙江环境通报》2002,22(12):1107-1111
Ninety-three pregnant women with Toxoplasma gondii seroconversion during pregnancy underwent prenatal diagnosis of fetal toxoplasmosis. The following tests were used: (1) amniocentesis for mouse inoculation (93 subjects), (2) amplification of T. gondii DNA by polymerase chain reaction (PCR) (79 subjects), and (3) cordocentesis for the detection of T. gondii-specific IgM antibodies (13 subjects). All patients had serial ultrasonographic scans to detect those fetuses with abnormalities that could be associated with congenital toxoplasmosis. Eighteen pregnancies (19.4%) had evidence of vertical transmission. A total of 11/18 (61.1%) had positive amniotic mouse inoculation test, while 10/12 (83.3%) had positive PCR results. The combination of both tests allowed the prenatal diagnosis in 17/18 infected fetuses (94.4%). All patients who underwent cordocentesis for the detection of T. gondii-specific IgM antibodies had negative results. However, in two of the above cases fetal toxoplasmosis was detected by amniotic fluid studies. In five of the infected fetuses there were abnormal ultrasonographic findings. All pregnancies with evidence of vertical transmission were terminated, whereas the remaining pregnancies proceeded normally to term. The present data showed that amniotic fluid studies, preferably PCR amplification of T. gondii DNA, are the best diagnostic tools for the detection of vertical transmission in pregnancies with seroconversion during pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
109.
Floating, organic crusts on liquid manure, stored as a result of animal production, reduce emission of ammonia (NH3) and other volatile compounds during storage. The occurrence of NO2- and NO3- in the crusts indicate the presence of actively metabolizing NH3-oxidizing bacteria (AOB) which may be partly responsible for this mitigation effect. Six manure tanks with organic covers (straw and natural) were surveyed to investigate the prevalence and potential activity ofAOB and its dependence on the O2 availability in the crust matrix as studied by electrochemical profiling. Oxygen penetration varied from <1 mm in young, poorly developed natural crusts and old straw crusts, to several centimeters in the old natural crusts. The AOB were ubiquitously present in all crusts investigated, but nitrifying activity could only be detected in old natural crusts and young straw crust with high O2 availability. In old natural crusts, total potential NH3 oxidation rates were similar to reported fluxes of NH3 from slurry without surface crust. These results indicate that old, natural surface crusts may develop into a porous matrix with high O2 availability that harbors an active population of aerobic microorganisms, including AOB. The microbial activity may thus contribute to a considerable reduction of ammonia emissions from slurry tanks with well-developed crusts. 相似文献
110.
Hamid Taheri Shahraiyni Sahar Sodoudi Andreas Kerschbaumer Ulrich Cubasch 《Environmental monitoring and assessment》2017,189(3):134
A dense monitoring network is vital for the reliable assessment of PM10 in different parts of an urban area. In this study, a new idea is employed for the re-construction of the 20 shut-down PM10 monitoring stations of Berlin. It endeavours to find the non-linear relationship between the hourly PM10 concentration of both the still operating and the shut-down PM10 monitoring stations by using a fuzzy modelling technique, called modified active learning method (MALM). In addition, the simulations were performed by using not only raw PM10 databases but also log-transformed PM10 databases for skewness reduction. According to the results of hourly PM10 simulation (root mean square error about 13.0 μg/m3, correlation coefficient 0.88), the shut-down stations have been appropriately simulated and the idea of dense monitoring network development by the re-construction of the shut-down stations was realised. The results of simulations using raw and log-transformed databases showed that data transformation has no significant effect on the performance of MALM in the simulation of shut-down PM10 stations. By the combination of the 11 still operating stations and the 20 re-constructed stations, a dense monitoring network was generated for Berlin and was utilised for the calculation of the reliable monthly and mean annual PM10 concentration for five different PM10 zones in Berlin (the suburban-background, urban-background, urban-traffic, rural-background and suburban-traffic areas). The results showed that the mean annual concentration of PM10 at the five zones increased by about 13.0% in 2014 (26.3 μg/m3) in comparison with 2013 (23.3 μg/m3). Furthermore, the mean annual concentration of PM10 in the traffic lanes of the suburban (2013 25.0 μg/m3, 2014 26.9 μg/m3) and urban (2013 27.7 μg/m3, 2014 31.3 μg/m3) areas is about 14 and 20% higher than the PM10 concentration of suburban-background (2013 21.3 μg/m3, 2014 24.5 μg/m3) and urban-background (2013 23.0 μg/m3, 2014 26.1 μg/m3) areas, respectively. 相似文献