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Öğe APPLICATION OF ARTIFICIAL NEURAL NETWORKS AND REGRESSION MODELS IN THE PREDICTION OF DAILY MAXIMUM PM10 CONCENTRATION IN DUZCE, TUKEY(Parlar Scientific Publications (P S P), 2014) Taşpınar, Fatih; Bozkurt, ZehraIncreasing levels of atmospheric particulate matter are known to adversely affect human health. Therefore, air quality predictions may provide important information in order to take actions for the public before the pollution happens. In this study, we presented artificial neural network (ANN), stepwise regression (SR) and multiple linear regression (MLR) models to forecast maximum daily PM10, concentrations one day ahead in Duzce, Turkey. Particularly, a special emphasis was put on the prediction of particulate levels during winter episodes. Inputs to the models include lagged values of maximum, minimum and standard deviations of PM10, concentrations, and some meteorological factors, which are all on daily basis. The output is the expected maximum concentration of PM10 in mu g.m(-3) for the following day. The data sets used in training and testing stages covered the daily averaged values of these variables for the period of 2011-2013. The results showed that selected inputs based on stepwise regression approach and use of cascading-training in multi-layer perceptron ANN (ANN-MLP) appeared to be promising with R-2 up to 0.69 and index-of-agreement up to 0.79. It is concluded that local monitoring systems associated with ANN model predictions may be a sound way to develop embedded online systems for public health.Öğe Application of artificial neural networks and regression models in the prediction of daily maximum PM10 concentration in Düzce, Tukey(Parlar Scientific Publications, 2014) Taşpınar, Fatih; Bozkurt, ZehraIncreasing levels of atmospheric particulate matter are known to adversely affect human health. Therefore, air quality predictions may provide important information in order to take actions for the public before the pollution happens. In this study, we presented artificial neural network (ANN), stepwise regression (SR) and multiple linear regression (MLR) models to forecast maximum daily PM1o concentrations one day ahead in Düzce, Turkey. Particularly, a special emphasis was put on the prediction of particulate levels during winter episodes. Inputs to the models include lagged values of maximum, minimum and standard deviations of PM1o concentrations, and some meteorological factors, which are all on daily basis. The output is the expected maximum concentration of PM10 in (?g.-3 for the following day. The data sets used in training and testing stages covered the daily averaged values of these variables for the period of 2011-2013. The results showed that selected inputs based on stepwise regression approach and use of cascading-training in multi-layer perceptron ANN (ANN-MLP) appeared to be promising with R2 up to 0.69 and index-of-agreement up to 0.79. It is concluded that local monitoring systems associated with ANN model predictions may be a sound way to develop embedded online systems for public health. © by PSP.Öğe Atmospheric ambient trace element concentrations of PM10 at urban and sub-urban sites: source apportionment and health risk estimation(Springer, 2018) Bozkurt, Zehra; Gaga, Eftade O.; Taşpınar, Fatih; Arı, Akif; Pekey, Beyhan; Pekey, Hakan; Üzmez, Özlem ÖzdenIn this study, PM10 concentrations and elemental (Al, Fe, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pb, and Bi) contents of particles were determined in Duzce, Turkey. The particulate matter samplings were carried out in the winter and summer seasons simultaneously in both urban and sub-urban sampling sites. The average PM10 concentration measured in the winter season was 86.4 and 27.3 mu g/m(3), respectively, in the urban and sub-urban sampling sites, while it was measured as 53.2 and 34.7 mu g/m(3) in the summer season. According to the results, it was observed that the PM10 levels and the element concentrations reached higher levels, especially at the urban sampling site, in the winter season. The positive matrix factorization model (PMF) was applied to the data set for source apportionment. Analysis with the PMF model revealed six factors for both the urban (coal combustion, traffic, oil combustion, industry, biomass combustion, and soil) and sub-urban (industry, oil combustion, traffic, road dust, soil resuspension, domestic heating) sampling sites. Loadings of grouped elements on these factors showed that the major sources of the elements in the atmosphere of Duzce were traffic, fossil fuel combustion, and metal industry-related emissions.Öğe Atmospheric concentrations of SO2, NO2, ozone and VOCs in Duzce, Turkey using passive air samplers: Sources, spatial and seasonal variations and health risk estimation(Turkish Natl Committee Air Pollution Res & Control-Tuncap, 2018) Bozkurt, Zehra; Üzmez, Özlem Özden; Döğeroğlu, Tuncay; Artun, Gülzade; Gaga, EftadeIn this research, seasonal and spatial distributions of inorganic and organic pollutants (sulphur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O-3) and also volatile organic compounds (VOCs)), were determined by passive sampling technique. Fifty sampling sites were selected considering possible sources in the study area. The sampling area were classified as urban (n=23), industrial (n=17) and rural (n=10) regions. Sampling campaigns were carried out for two-week periods in fall, winter, spring and summer seasons in all regions. Benzene and toluene concentrations were found to be the highest in winter at the traffic-dense sites and lowest concentrations were measured at rural sampling sites in summer. Concentrations of NO2 were higher at sampling sites with high traffic density in winter. A much uniform distribution was observed for SO2 in all seasons. However higher levels were observed in winter compared to other seasons due to use of coal for domestic heating. Low O-3 concentrations were measured in winter while higher concentrations were measured in summer. Based on principal component analysis (PCA), four factors (gasoline vehicle emissions, diesel vehicle emissions, industrial emissions and fossil fuel combustion) were identified that could explain about 78% of the system variance of the measured pollutants in the city. Health risk assessment revealed that the safe level of 1 x 10(-6) (United States Environmental Protection Agency's (USEPA) acceptable risk value) was exceeded for benzene in all sampling sites in whole region, but non-carcinogenic risk values were at safe level.Öğe Characterization and source estimates of primary and secondary carbonaceous aerosols at urban and suburban atmospheres of Duzce, Turkey(Springer Heidelberg, 2019) Kılavuz, Seda Aslan; Bozkurt, Zehra; Öztürk, FatmaDuzce is one of the cities located in the western Black Sea region of Turkey with a population of 377,610 in 2017 (TUIK, 2017). There is no satisfying scientific information available to address the contribution of primary and secondary sources of carbonaceous aerosols to the observed PM10 levels in the city. The main objective of the study is to determine the levels and sources of carbonaceous aerosols in PM10. For this purpose, PM10 samples were collected at urban and suburban locations in Duzce during winter and summer season in 2015. Average summer OC and EC concentrations in the urban area were 9.5 and 1.3gm(-3), respectively, while the corresponding concentrations were observed as 28.5 and 2.3gm(-3), respectively for winter season. Summer mean OC and EC levels at the suburban site were 5.46 and 0.37gm(-3), respectively, while those for winter were found as 6.68 and 0.61gm(-3).The contributions of OC and EC to measured PM10 levels were found in the range of 10% to 60% and 1% to 7%, respectively, at the urban station while the associated contributions were in the range of 10% to 50% and 0.6% to 6%, respectively, at the suburban station. The concentrations measured during winter months in both areas were found to be higher than those measured during summer months. The EC tracer method was used in order to estimate the SOC contribution. The contribution of SOC concentrations to the total PM10 mass was found to be higher during winter in the urban area and during summer in the suburban area.Öğe Determination of airborne trace elements in an urban area using lichens as biomonitor(Springer, 2017) Bozkurt, ZehraThe amounts of elements emitted from industrial, domestic, and vehicle sources in Duce through the analyses of lichens, which are bioindicators of air pollution, were determined in this research. Concentrations of Al, Fe, Cr, Mn, Co, Ni, Cu, Zn, As, V, Cd, Hg, and Pb in the lichens that were collected from 40 different points were analyzed using an inductively coupled plasma (ICP-MS) device. The highest concentration values were detected for Fe and Al, while the lowest concentration values were detected for Cd and Hg. Distribution maps of elements were created using geographic information systems. The distribution maps showed how the concentrations of elements for Duzce have changed across the city. According to our results, the elements sourced from traffic and combustion, such as Cr, Co, Ni, Cu, As, and V, have the highest concentrations in the city center near the traffic.Öğe Determination of the personal, indoor and outdoor exposure levels of inorganic gaseous pollutants in different microenvironments in an industrial city(Springer, 2015) Bozkurt, Zehra; Doğan, Güray; Arslanbaş, Demet; Pekey, Beyhan; Pekey, Hakan; Dumanoğlu, Yetkin; Tuncel, GürdalWe measured SO2, NO2 and O-3 concentrations during the summer and winter in Kocaeli, Turkey. The sampling was carried out indoors and outdoors at homes, schools and offices. Personal samplers were also used to determine personal exposures to these pollutants. High NO2 and SO2 concentrations were observed in outdoor samples collected close to locations characterized by heavy urban traffic. Concentrations of O-3, on the other hand, were higher in rural areas around the city due to ozone distillation. For both sampling periods, the concentrations of outdoor SO2 and O-3 were higher than for indoor and personal samples; however, the NO2 concentrations were higher in indoor and personal samples, indicating that outdoor sources significantly contribute to indoor SO2 and O-3 levels and that indoor NO2 concentrations are primarily modulated by sources within buildings. Seasonal variations in pollutant concentrations showed statistically significant differences. Indoor and outdoor concentrations of NO2 and SO2 measured in the winter were higher than the levels measured in the summer; O-3 concentrations, on the other hand, exhibited the opposite trend. Active-to-passive concentration ratios for NO2, SO2 and O-3 were 0.99, 1.08 and 1.16, respectively; the corresponding outdoor ratios were 0.95, 0.99 and 1.00.Öğe Düzce İlinde İlkokulların İç ve Dış Ortamlarındaki Toz Örneklerinde PCB Düzeylerinin Belirlenmesi(2022) Kılavuz, Seda Aslan; Tekli, Aslı; Bozkurt, ZehraSanayi, trafik ve konut bölgelerinin iç içe geçtiği Düzce ili hızla gelişmekte ve bu nedenle bölgede çevresel kirlilik yoğun olarak hissedilmektedir. Emisyon kaynaklarından çıkan hava kirleticileri ilin coğrafi konumu sebebi dağılamamakta ve önemli sağlık riskleri oluşturmaktadır. Bu çalışmada bölgesel kirlilik dağılımı ve çeşitli emisyon kaynaklarını açıklayabilmek için farklı konumlarda toz örnekleri toplanmıştır. Çocuklar hava kirleticileri açısından daha hassas risk grubunda yer alması nedeniyle örneklemeler için ilkokulların iç ve dış ortamları seçilmiştir. Toplanan toz örneklerinde PCB düzeyleri belirlenmiştir. Mekanik süpürme tekniği kullanılarak toplanan örneklerde PCB analizleri Gaz Kromatografisi/Kütle Spektrometresi (GC/MS) cihazı kullanılarak gerçekleştirilmiştir. Elde edilen sonuçlarda dış ortam ?PCB konsantrasyonları 0,737-22,307 ng/gr arasında olup, ortalama 3,626 ng/gr olarak bulunmuştur. İç ortam ?PCB konsantrasyonları ise 17,17–294,22 ng/gr arasında olup, ortalama 66,89 ng/gr olarak bulunmuştur. İç ortam örneklerinde yüksek ?PCB konsantrasyonları, iç ortam kaynaklarının katkısının ve dış ortamdan taşınım yolu ile iç ortamlarda gerçekleşen birikimin etkisinin daha fazla olduğunu göstermektedir. Dış ortam kaynaklarına göre yapılan değerlendirmede en yüksek konsantrasyonlar daha çok endüstriye yakın noktalarda elde edilmiştir. En düşük konsantrasyonlar ise kırsal örnekleme noktalarında ölçülmüştür.Öğe Düzce İlinde Kentsel ve Yarı Kentsel Örnekleme Noktalarında Atmosferik İnorganik İyonların Kaynaklarının Belirlenmesi(2018) Bozkurt, ZehraBu çalışmada, Düzce ilinde atmosferik partiküllerin (PM10) yapısında bulunan suda çözünür inorganik iyonların konsantrasyonları belirlenmiştir. Örneklemeler eş zamanlı olarak kentsel ve yarı kentsel özellikte iki örnekleme noktasında, yaz ve kış olmak üzere iki mevsimde gerçekleştirilmiştir. Partikül madde örneklerinde bulunan inorganik iyonların analizleri için iyon kromotografisi cihazı kullanılmıştır. Çalışmada, iyonların yaz ve kış konsantrasyonlarını karşılaştırmak için Mann-Whitney U testi uygulanmıştır. Test sonuçlarına göre kentsel örnekleme alanında SO42- ve Ca2 iyonları dışında, yarı kentsel örnekleme alanında ise NO-, Mg2 , NH4iyonları dışında tüm iyonlar istatiksel olarak anlamlı (p 0.05,% 95 güven seviyesi) mevsimsel farklar göstermiştir. Ölçülen iyonik türlerinin kaynaklarının açıklanabilmesi amacı ile veri setlerine Temel bileşenler analizi (PCA) tekniği uygulanmıştır. PCA çalışması sonucunda kentsel bölgede inorganik iyonlara ait sistem varyansının yaklaşık % 88'ini yarı kentsel örnekleme noktasında % 80'ini açıklayabilen toplam 3 faktör belirlenmiştir. Bu faktörler altında toplanan iyonlar incelendiğinde Düzce atmosferinde inorganik iyon içeriğinin en önemli kaynaklarının, trafik, yanma, deniz tuzu ve toprak olduğu belirlenmiştir. Kirleticilerin uzun menzilli taşınımını belirlemek için çalışmaya HYSPLIT modeli uygulanmıştır. Böylece, hava kütlelerinin geri yörüngeleri ve kaynak bölgeleri tespit edilmiştirÖğe Heavy metal pollution and health risk assessment of road dust on selected highways in Duzce, Turkey(Taylor & Francis Ltd, 2018) Taşpınar, Fatih; Bozkurt, ZehraIn this study, road dust samples from state roads D-100 and D-655 passing through the city of Duzce, Turkey were analyzed using ICP-MS to ascertain heavy metal pollution, and also to evaluate possible risks to human health. Some pollution indices such as enrichment factors (EFs), geo-accumulation index (I-geo) and integrated pollution index (IPI) were calculated to determine the pollution levels of metals. According to the mean EF values, Zn, Mo, and Pb exhibited significant enrichment, while enrichment of As, Cd, Sn, and Sb was very high. The I-geo values for Pb, Ba, Mo, Zn, Cu, Mn, and Cr indicated an extremely polluted environment whereas those for Sc, V, Fe, As, Cd, Sn, and Sb indicated moderate to strong pollution of the environment. The IPI values of Pb and Mo were also at extreme levels due to vehicle traffic related contamination along the roads. Analysis of the road dust matrix indicated the mixed effect of the fossil fuel combustion for residential heating and industrial activities within the studied area as well as traffic originated pollution. Cluster analysis revealed that sampling area has been influenced by mainly three pollution sources: (i) traffic and industrial activities, (ii) polluted soil due to accumulation, and (iii) fossil fuel combustion. According to human health risk assessment studies, a level lower than 1.0 has been determined to be a non-cancer health risk. However, a total hazard index level of 1.4 poses a significant non-cancer health risk for children. Fortunately, a total lifetime cancer risk value of 8.8x10(-8) was found, and this is considered safe.Öğe PM10 ve PM2.5 Boyutundaki Atmosferik Partiküllerin Bölgesel, Mevsimsel Değişimlerinin ve Meteorolojik Parametrelerle İlişkilerinin İncelenmesi(2018) Bozkurt, ZehraBu çalışmada, Marmara Temiz Hava Merkezi'ne (MTHM) ait hava kalitesi ölçüm istasyonlarından eş zamanlıPM10 ve PM2.5 örneklemesi yapılan Edirne-Keşan, İstanbul-Silivri, İstanbul-Ümraniye, Kocaeli-Kandıra,Tekirdağ-Çerkezköy ve Yalova-Armutlu istasyonlarında 2017 yılında ölçülen PM10 ve PM2.5 kütlekonsantrasyonlarının mevsimsel ve günlük değişimleri incelenmiştir. Çalışmada, PM10 ve PM2.5konsantrasyonlarının mevsimsel farklılıklarını karşılaştırmak için Mann-Whitney U testi uygulanmıştır.Mevsimsel faklılıkların en belirgin olduğu istasyonlar kentsel Tekirdağ ve Çerkezköy istasyonları ile kırsalKandıra istasyonu olarak belirlenmiştir. Konsantrasyonlar, kentsel istasyonlarda kış mevsiminde artarken, kırsalistasyonlarda yaz mevsiminde artmaktadır. Partikül boyutu ile kirletici kaynakları arasındaki ilişkininanlaşılabilesi için PM2.5/PM10 oranları hesaplanmış ve bu oranlar incelenen istasyonların özelliklerine göredeğerlendirilmiştir. Yapılan değerlendirmeler, kış mevsiminde PM2.5, yaz mevsiminde ise PM10 boyutundakikirleticilerin hakim olduğunu göstermektedir. İncelenen istasyonlar için hesaplanan ortalama konsantrayonlar vePM2.5/PM10 oranları, farklı ülkelerde farklı özelliklerde şehirlerde yapılan benzer çalışmalarla karşılaştırılaraksonuçların literatür ile uyumlu olduğu belirlenmiştir. Çalışmada, PM10 ve PM2.5 konsantrasyonlarının birbirleriile ve meteorolojik parametrelerle anlamlı ilişkiler gösterdiği Spearman korelasyon katsayıları hesaplanarakanlaşılmıştır.Öğe Seasonal variation of water-soluble inorganic ions in PM10 in a city of northwestern Turkey(Taylor & Francis Ltd, 2018) Bozkurt, ZehraThe objective of this study was to determine the concentrations of inorganic ions present in particulate matter smaller than 10 mm (PM10), released into the environment by industrial, domestic and mobile sources in Duzce. To assess spatial variations, samples were collected from two sampling sites that had urban and suburban characteristics. Further, the process was carried out in two seasons to understand the seasonal variations. An ion chromatography device was used for analyzing the inorganic ion content in the collected samples. The highest levels of inorganic ion concentrations were measured at the urban sampling site during the winter campaign. Furthermore, the highest ion concentrations were measured for SO42- ion at both sampling sites and during both seasons, while the lowest concentrations were measured for Br-. Moreover, there were significant relationships between meteorological parameters and ion concentrations. A comparison of the cation and anion equivalence values using seasonal CE/AE (cation equivalence/anion equivalence) ratios showed that the aerosol matter had alkaline characteristics during both seasons. The mean value for the CE/AE ratios was 1.58 in winter and 2.06 in summer at the urban sampling site and 1.36 in winter and 1.52 in summer at the suburban sampling site. The interrelationships among the ions were determined by Pearson correlation analysis. Based on the correlation analyses, the ions emitted from common sources and those exposed to similar atmospheric conditions displayed strong correlations with each other.Öğe Source Identification of Volatile Organic Compounds and Particulate Matters in an Urban and Industrial Areas of Turkey(Foundation Environmental Protection & Research-Fepr, 2015) Pekey, Hakan; Pekey, Beyhan; Arslanbaş, Demet; Bozkurt, Zehra; Doğan, Güray; Tuncel, GürdalElevated levels of volatile organic compounds (VOCs) and particulate matters have been observed in recent years in Kocaeli, Turkey, despite improvements in pollution prevention technology that have led to a reduction in gas and particulate emissions. Local authorities should devise alternative strategies to reduce the possible health effects of a variety of pollutants that affect air quality. The objective of this study was to identify potential sources of VOCs, fine particulate matter (PM2.5) and coarse particulate matter (PM10) concentrations in atmospheric aerosols that were collected in the highly industrialised area of Kocaeli, Turkey, during the winter and summer months by using wind directions. Samples were collected from May 2006 to January 2007, and concentrations of eight elements (As, Cr, Cu, Mn, Ni, Pb, V and Zn) were measured using energy dispersive X-ray fluorescence (EDXRF) and wavelength dispersive X-ray fluorescence (WDXRF) spectrometer. Samples were analysed for thirteen VOCs, including benzene, toluene, m/p-xylene, o-xylene, ethylbenzene, styrene, cyclohexane, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, hexane, nonane and dodecane using thermal desorption (TD) and a gas chromatography/flame ionisation detector (GC/FID). The results show that vehicular emissions, oil and coal combustions, petroleum refinery and hazardous and medical waste incinerator are the significant sources of VOCs, PM2.5 and PM10 concentrations in Kocaeli.
