1. Carbonaceous aerosols in contrasting atmospheric environments in Greek cities : evaluation of the EC-tracer methods for secondary organic carbon estimationDimitris G. Kaskaoutis, Georgios Grivas, Christina Theodosi, M. Tsagkaraki, D. Paraskevopoulou, Iasonas Stavroulas, Eleni Liakakou, Antonis Gkikas, Nikolaos Hatzianastassiou, Cheng Wu, 2020, original scientific article Abstract: This study examines the carbonaceous-aerosol characteristics at three contrasting urban environments in Greece (Ioannina, Athens, and Heraklion), on the basis of 12 h sampling during winter (January to February 2013), aiming to explore the inter-site differences in atmospheric composition and carbonaceous-aerosol characteristics and sources. The winter-average organic carbon (OC) and elemental carbon (EC) concentrations in Ioannina were found to be 28.50 and 4.33 µg m−3, respectively, much higher than those in Heraklion (3.86 µg m−3 for OC and 2.29 µg m−3 for EC) and Athens (7.63 µg m−3 for OC and 2.44 µg m−3 for EC). The winter OC/EC ratio in Ioannina (6.53) was found to be almost three times that in Heraklion (2.03), indicating a larger impact of wood combustion, especially during the night, whereas in Heraklion, emissions from biomass burning were found to be less intense. Estimations of primary and secondary organic carbon (POC and SOC) using the EC-tracer method, and specifically its minimum R-squared (MRS) variant, revealed large differences between the sites, with a prevalence of POC (67–80%) in Ioannina and Athens and with a larger SOC fraction (53%) in Heraklion. SOC estimates were also obtained using the 5% and 25% percentiles of the OC/EC data to determine the (OC/EC)pri, leading to results contrasting to the MRS approach in Ioannina (70–74% for SOC). Although the MRS method provides generally more robust results, it may significantly underestimate SOC levels in environments highly burdened by biomass burning, as the fast-oxidized semi-volatile OC associated with combustion sources is classified in POC. Further analysis in Athens revealed that the difference in SOC estimates between the 5% percentile and MRS methods coincided with the semi-volatile oxygenated organic aerosol as quantified by aerosol mass spectrometry. Finally, the OC/Kbb+ ratio was used as tracer for decomposition of the POC into fossil-fuel and biomass-burning components, indicating the prevalence of biomass-burning POC, especially in Ioannina (77%).
Keywords: carbonaceous aerosols, inorganic species, POC-SOC estimation, biomass burning, MRS method, Greece
Published in RUNG: 10.05.2024; Views: 136; Downloads: 3
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2. Click-through rate estimation using CHAID classification tree model : case study of direct benefit transfer in IndiaRajan Gupta, Saibal K. Pal, 2019, published scientific conference contribution Abstract: Click-Through Rate (CTR) is referred to as the number of clicks on a particular advertisement as compared to the number of impressions on it. It is an important measure to find the effectiveness of any online advertising campaign. The effectiveness of online advertisements through calculations of ROI can be done through the measurement of CTR. There are multiple ways of detecting CTR in past; however, this study focuses on machine learning based classification model. Important parameters are judged on the basis of user behavior toward online ads and CHAID tree model is used to classify the pattern for successful and unsuccessful clicks. The model is implemented using SPSS version 21.0. The dataset used for the testing has been taken from Kaggle website as the data is from anonymous company’s ad campaign given to Kaggle for research purpose. A total of 83.8% accuracy is reported for the classification model used. This implies that CHAID can be used for less critical problems where very high stakes are not involved. This study is useful for online marketers and analytics professionals for assessing the CHAID model’s performance in online advertising world.
Keywords: click-through rate, online advertisements, classification tree, mobile ads, click estimation
Published in RUNG: 02.04.2021; Views: 1717; Downloads: 14
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3. ASYMMETRIES IN SUB-EXTRACTION OUT OF NP IN SLOVENIAN : A MAGNITUDE ESTIMATION STUDYArthur Stepanov, Manca Mušič, Penka Stateva, 2016, original scientific article Abstract: In this work, we aim to clarify the empirical paradigm that bears on two aspects of syntactic locality in Slovenian. First, building on previous work, we investigate how
robustly Slovenian observes the syntactic locality constraint precluding constituent sub-extraction out of subject noun phrases. Second, we ask whether Slovenian allows Left Branch Extraction in interrogative and non-interrogative sentences. To elucidate both issues, we conducted a magnitude estimation study, the results of which support our previous claim that there is a subject island effect in Slovenian. Furthermore,
our results suggest that Slovenian disallows Left Branch Extraction, in contrast with some other Slavic languages. We also discuss theoretical consequences of our empirical findings.
Keywords: syntactic island, Left Branch extraction, magnitude estimation, Slovenian
Published in RUNG: 03.01.2017; Views: 4908; Downloads: 251
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