column number
Recently Published Documents


TOTAL DOCUMENTS

34
(FIVE YEARS 7)

H-INDEX

3
(FIVE YEARS 0)

2021 ◽  
Vol 8 (2) ◽  
Author(s):  
Elvira Pradipta Sutiana ◽  
Risha Fatikha Sari ◽  
Ajat Sudrajat

"The Influence of Reference Groups and Culture on the Decision to Become Members of the Dance Studio" under the guidance of Ajat Sudrajat, SE., MM. The consumer behaviour in making purchasing decisions can be influenced by three factors including internal factors, external factors, and the decision-making process. The study entitled "The Influence of Reference Group and Culture on the Decision to Become a Member of the Dance Studio aims to analyze the influence of X1 and X2 on Y" has a population of 329 people and a sample of 100 people. By using a quantitative approach and descriptive analysis, in the variable X1 the dimension of value expression obtained the highest average score with a percentage of 51.82%, in the X2 variable the highest was the view of 59.50%, in the variable Y the highest was personality at 25.57%. Whereas in the verification analysis, the relationship between X1 and X2 is 0.426 which means that the correlation is moderate. For 5% error the two-tailed test and df = n - 3 = 97 is 1.66071. Because the t statistic> from t table (4.328> 1.66071), Ho is rejected. The significant column number is 0.000 or the probability is far below 0.05. So it means that X1 and X2 partially have a significant effect on Y.From the ANOVA test or F test, it is found that the F count is 19.714 with a significant level indicating a value of 0.000 which means less than 5%, it can be concluded that X1 and X2 are Simultaneously affects Decision Y. Keywords : Reference Group, Culture, Purchasing Decision


2021 ◽  
Vol 13 (18) ◽  
pp. 3784
Author(s):  
Patryk Tadeusz Grzybowski ◽  
Krzysztof Mirosław Markowicz ◽  
Jan Paweł Musiał

The COVID-19 pandemic has affected many aspects of human well-being including air quality. The present study aims at quantifying this effect by means of ground-level concentrations of NO2, PM2.5, as well as aerosol optical depth (AOD) measurements and tropospheric NO2 column number density (NO2 TVCD), during the imposed governmental restrictions in spring 2020. The analyses were performed for both urban and non-built-up areas across the whole of Poland accompanied by Warsaw (urban site) and Strzyzow (a background site). The results revealed that mean PM2.5 concentrations in spring 2020 for urban and non-built-up areas across Poland and for Warsaw were 20%, 23%, 15% lower than the 10-year average, respectively. Analogous mean NO2 concentrations were lower by 20%, 18%, 30% and NO2 TVCD revealed 9%, 4%, 9% reductions in 2020 as compared to 2019. Regarding mean AOD, retrieved from MERRA-2 reanalysis, it was found that for the whole of Poland during spring 2020 the reduction in AOD as compared to the 10-year average was 15%. The contribution of the lockdown within total air pollution reduction is not easily assessable due to anomalous weather conditions in 2020 which resulted in advection of clean air masses identified from MERRA-2 reanalysis and Strzyzow observatory.


Atmosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 896
Author(s):  
Marcin Kawka ◽  
Joanna Struzewska ◽  
Jacek W. Kaminski

The TROPOMI instrument aboard Sentinel-5P is a relatively new, high-resolution source of information about atmosphere composition. One of the primary atmospheric trace gases that we can observe is nitrogen dioxide. Thanks to TROPOMI capabilities (high resolution and short revisit time), one can describe regional and seasonal NO2 concentration patterns. Thus far, such patterns have been analysed by either ground measurements (which have been limited to specific locations and only to the near-surface troposphere layer) or numerical models. This paper compares the TROPOMI and GEM-AQ derived vertical column densities (VCD) over Poland, focusing on large point sources. Although well established in atmospheric science, the GEM-AQ simulations are always based on emission data, which in the case of the energy sector were reported by stack operators. In addition, we checked how cloudy conditions influence TROPOMI results. Finally, we tried to link the NO2 column number densities with surface concentration using boundary layer height as an additional explanatory variable. Our results showed a general underestimation of NO2 tropospheric column number density by the GEM-AQ model (compared to the TROPOMI). However, for the locations of the most significant point sources, we noticed a systematic overestimation by the GEM-AQ model (excluding spring and summer months when TROPOMI presents larger NO2 VCDs than GEM-AQ). For the winter months, we have found TROPOMI NO2 VCD results highly dependent on the choice of qa_value threshold.


Author(s):  
Marcin Kawka ◽  
Joanna Strużewska ◽  
Jacek Kamiński

TRPOMI instrument aboard Sentinel-5P is a relatively new, high-resolution source of information about atmosphere composition. One of the primary atmospheric trace gases that we can observe through it is nitrogen dioxide. By now, we were using the chemical weather model (GEM-AQ) as a mean for estimating nitrogen dioxide concentration on a regional scale. Although well established in atmospheric science, the GEM-AQ simulations were always based on emission data, which in the case of the energy sector were reported by stack owners. In this paper, we attempted to compare the TROPOMI and GEM-AQ derived VCDs over Poland with a particular focus on large point emitters. We also checked how cloudy conditions influence TROPOMI results. Finally, we tried to link the NO2 column number densities with surface concentration using boundary layer height as an additional explanatory variable


Author(s):  
Marcin Kawka ◽  
Joanna Strużewska ◽  
Jacek Kamiński

TRPOMI instrument aboard Sentinel-5P is a relatively new, high-resolution source of information about atmosphere composition. One of the primary atmospheric trace gases that we can observe through it is nitrogen dioxide. By now, we were using the chemical weather model (GEM-AQ) as a mean for estimating nitrogen dioxide concentration on a regional scale. Although well established in atmospheric science, the GEM-AQ simulations were always based on emission data, which in the case of the energy sector were reported by stack owners. In this paper, we attempted to compare the TROPOMI and GEM-AQ derived VCDs over Poland with a particular focus on large point emitters. We also checked how cloudy conditions influence TROPOMI results. Finally, we tried to link the NO2 column number densities with surface concentration using boundary layer height as an additional explanatory variable


2020 ◽  
Vol 412 (30) ◽  
pp. 8225-8227
Author(s):  
Slavica Ražić ◽  
Marcela A. Segundo

2019 ◽  
Vol 411 (17) ◽  
pp. 3695-3698
Author(s):  
Slavica Ražić ◽  
Marcela A. Segundo ◽  
Günter Gauglitz

2018 ◽  
Vol 11 (12) ◽  
pp. 6627-6650 ◽  
Author(s):  
Guangliang Fu ◽  
Otto Hasekamp

Abstract. Polarimeter retrievals can provide detailed and accurate information on aerosol microphysical and optical properties. The SRON aerosol algorithm is one of the few retrieval approaches that can fully exploit this information. The algorithm core is a two-mode retrieval in which effective radius (reff), effective variance (veff), refractive index, and column number are retrieved for each mode; the fraction of spheres for the coarse mode and an aerosol layer height are also retrieved. Further, land and ocean properties are retrieved simultaneously with the aerosol properties. In this contribution, we extend the SRON aerosol algorithm by implementing a multimode approach in which each mode has fixed reff and veff. In this way the algorithm obtains more flexibility in describing the aerosol size distribution and avoids the high nonlinear dependence of the forward model on the aerosol size parameters. Conversely, the approach depends on the choice of the modes. We compare the performances of multimode retrievals (varying the number of modes from 2 to 10) with those based on the original (parametric) two-mode approach. Experiments with both synthetic measurements and real measurements (PARASOL satellite level-1 data of intensity and polarization) are conducted. The synthetic data experiments show that multimode retrievals are good alternatives to the parametric two-mode approach. It is found that for multimode approaches, with five modes the retrieval results can already be good for most parameters. The real data experiments (validated with AERONET data) show that, for the aerosol optical thickness (AOT), multimode approaches achieve higher accuracy than the parametric two-mode approach. For single scattering albedo (SSA), both approaches have similar performances.


2018 ◽  
Vol 410 (20) ◽  
pp. 4765-4766
Author(s):  
Wolfgang Buchberger ◽  
Sibel A. Özkan ◽  
Slavica Razic

2017 ◽  
Vol 93 ◽  
pp. 228-229
Author(s):  
Wolfgang Buchberger ◽  
Slavica Razic

Sign in / Sign up

Export Citation Format

Share Document