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5. A Novel Way of Optimizing Headlight Distributions Based on Real Life Traffic and Eye Tracking Data Part 1: Idealized Baseline Distribution

Author

Kobbert, Jonas, Erkan, Anil, Bullough, John D., Khanh, Tran Quoc, Kobbert, Jonas, Erkan, Anil, Bullough, John D., and Khanh, Tran Quoc

Abstract

In order to find optimized headlight distributions based on real traffic data, a three-step approach is chosen. Since the complete investigations are too extensive to fit into a single publication, this paper is the first in a series of three publications. Over three papers, a novel way to optimize automotive headlight distributions based on real-life traffic and eye-tracking data is presented, based on 119 test subjects who participated in over 15,000 km of driving, including recordings of gaze behavior, light data, detection distances, and other objects in traffic. In the present paper, a baseline headlight distribution is derived from a series of detection tests conducted under ideal conditions, with a total of three tests, each with 19–30 subjects, conducted within the same test environment. In the first test, the influence of low beam intensity on the detection of pedestrians on the sidewalk (5.0 m from the center of the driving lane) is investigated. In the second test, the influence of different high beam intensities was investigated for the same detection task. In the third test, the headlight distribution and intensity are kept constant at a representative high beam level, but the detection task is changed. In this test, the pedestrian detection target is placed along different detection angles, ranging from immediately adjacent to the road (2.5°) to 15.5 m away from the center of the driving lane (8.0°). As mentioned, all of these tests were conducted under ideal conditions, with the studies taking place on an airfield with a 1.2 km long straight road and normal road markings, but without oncoming traffic, tasks other than keeping the vehicle with cruise control within its lane, or other distracting objects present. The tests yielded two sets of data; the first is the intensity, based on the first two studies, needed to ensure sufficient intensity to detect objects under ideal conditions at distances needed for different driving speeds. The last test then

Published
2024

6. A Novel Way of Optimizing Headlight Distributions Based on Real-Life Traffic and Eye-Tracking Data Part 2: Analysis of Real-World Traffic Environments Data in Germany

Author

Kobbert, Jonas, Erkan, Anil, Bullough, John D., Khanh, Tran Quoc, Kobbert, Jonas, Erkan, Anil, Bullough, John D., and Khanh, Tran Quoc

Abstract

In order to find optimized headlight distributions based on real traffic data, a three-step approach has been chosen. Since the complete investigations are too extensive to fit into one single publication, this paper is the second of three papers. Over the course of these papers, a novel way to optimize automotive light distributions based on real-life traffic and eye-tracking data is presented. Over all three papers, 119 test subjects participated in the studies, with over 15,000 km of driving, including recordings of gaze behavior, light data, detection distances and other objects in traffic. In the first paper, an ideal headlight distribution for straight roads with no other road users was identified. The second paper aims to collect the data required to modify this idealized headlight distribution for use on real roads. The first step is to find the extent to which real roads differ from an ideal, straight road. To do this, the German traffic space was analyzed. A new test vehicle recorded video and GPS data over a selected route. The video data were then evaluated by a machine learning algorithm. Object recognition software was used to find different traffic participants and road signs. Camera calibrations were used to find the exact angles of these objects. Using publicly available road data combined with the recorded GPS data, the video data were split into different road categories, and traffic object distributions were calculated for urban roads, country roads and motorways. The resulting analyses provided representative distributions of vehicles and highway signs along different types of roadways and roadway geometries. The GPS data were also used to find the curvature distributions along the selected route. These data were then used to optimize segment sizes for an adaptive driving beam. Overall, increasing the number of segments above 100 did not have appreciable benefits. These data will also be used in the third paper, where along the same route, the g

Published
2024

7. An Analysis of Visibility Requirements and Reaction Times of Near-Field Projections

Author

Schlürscheid, Tabea, Stuckert, Alexander, Erkan, Anil, Khanh, Tran Quoc, Schlürscheid, Tabea, Stuckert, Alexander, Erkan, Anil, and Khanh, Tran Quoc

Abstract

Successful communication between highly automated vehicles and vulnerable road users will be crucial in the future. In addition to the technical requirements of the communication system, the projected content is also essential to ensure successful communication. For this purpose, previous studies have investigated the necessary technical requirements for near-field projections. However, the impact of the presentation content, whether symbol- or text-based, on the technological domain, has yet to be investigated. Therefore, a psychophysical subject study investigated the necessary detection probability for symbol- and text-based projection in the near-field of a vehicle. The visibility of symbol- and text-based projections were analyzed by the subject’s detection rate of the tested projection in an ambient lighting scenario of 20 lx at two different distances. Additionally, the corresponding reaction time of the subjects was measured. The results of the subject study showed that, contrarily, an arbitrary increase does not reduce the reaction time and thus saturates at a level of 650 ms before the 90% detection threshold for both projection contents. The observed detection contrast indicates that symbol-based projections need approximately 25% less contrast level than text-based projections to reach a 90% detection rate.

Published
2024

14. A Novel Way of Optimizing Headlight Distributions Based on Real-Life Traffic and Eye Tracking Data Part 3: Driver Gaze Behaviour on Real Roads and Optimized Light Distribution

Author

Kobbert, Jonas, Erkan, Anil, Bullough, John D., Khanh, Tran Quoc, Kobbert, Jonas, Erkan, Anil, Bullough, John D., and Khanh, Tran Quoc

Abstract

In order to find optimized headlight distributions based on real traffic data, a three-step approach has been chosen. The complete investigations are too extensive to fit into a single paper; this paper is the last of a three part series. Over the three papers, a novel way to optimize automotive headlight distributions based on real-life traffic and eye tracking data is presented. Across all three papers, a total of 119 test subjects participated in the studies with over 15,000 km of driving, including recordings of gaze behaviour, light data, detection distances, and other objects in traffic. In this third paper, driver gaze behaviour is recorded while driving a 128 km round course, covering urban roads, country roads, and motorways. This gaze behaviour is then analysed and compared to prior work covering driver gaze behaviour. Comparing the gaze distributions with roadway object distributions from part two of this series, Analysis of Real-World Traffic Data in Germany and combining them with the idealized baseline headlight distribution from part one, different optimized headlight distributions can be generated. These headlight distributions can be optimized for different driving requirements based on the data that is used and weighting the different road types differently. The resulting headlight distribution is then compared to a standard light distribution in terms of the required luminous flux, angular distribution, and overall shape. Nonetheless, it is the overall approach that has been taken that we see as the primary novel outcome of this investigation, even more than the actual distribution resulting from this effort.

Published
2023

15. Optimierung von Frontscheinwerferlichtverteilungen anhand wahrnehmungsphysiologischer Kriterien

Author

Erkan, Anil and Erkan, Anil

Abstract

Die vorliegende Arbeit beschäftigt sich mit der Optimierung von Kfz-Frontscheinwerferlichtverteilungen anhand wahrnehmungsphysiologischer Kriterien, um sowohl die subjektiv wahrgenommene als auch die objektive Sicherheit im nächtlichen Straßenverkehr zu erhöhen. Hierfür werden innerhalb und außerhalb geschlossener Ortschaften insgesamt vier Feldstudien zur Helligkeitswahrnehmung und Objektdetektion durchgeführt. Die durchgeführten Studien zur Helligkeitswahrnehmung zeigen, dass der hierfür relevante Bereich sich bis zu einer Entfernung von 32 m vor dem Fahrzeug erstreckt. Des Weiteren zeigen die Studien, dass die Helligkeitswahrnehmung von Fahrzeugführern sowohl von der Fahrgeschwindigkeit als auch von dem bereits ohne die Kfz-Beleuchtung vorhandenen Leuchtdichteniveau auf der Fahrbahn abhängt. So werden gleiche Fahrbahnleuchtdichten bei höheren Fahrgeschwindigkeiten dunkler wahrgenommen. Wird das Leuchtdichteniveau der Fahrbahn erhöht, so ist ein exponentieller Anstieg der für das subjektive Sicherheitsgefühl erforderlichen Fahrbahnleuchtdichte aufgrund der relativen und logarithmischen Helligkeitswahrnehmung des Menschen zu beobachten. Insgesamt wird für die Auslegung von Frontscheinwerferlichtverteilungen für die Vorfeldausleuchtung eine durchschnittliche Fahrbahnleuchtdichte von 1,0 cd m^-2 empfohlen, um ein adäquates Sicherheitsgefühl hervorzurufen. Die Studien zur Objektdetektion zeigen, dass außerhalb geschlossener Ortschaften ein Visibility Level VL von 13,35 benötigt wird, um Objekte sicher zu detektieren. Zusätzlich ist das benötigte Visibility Level winkelabhängig. So erreicht das benötigte Visibility Level im fovealen Bereich des Sichtfelds seinen Maximalwert und nimmt in der Peripherie gaußförmig ab. Innerhalb geschlossener Ortschaften sind die Beleuchtungssituationen derart komplex, dass eine statische Optimierung von Frontscheinwerferlichtverteilungen nicht sinnvoll ist. Eine kamerabasierte und dynamisch voll adaptive Lichtverteilungsregelung ist im n

Published
2023

22. Determination of Speed-Dependent Roadway Luminance for an Adequate Feeling of Safety at Nighttime Driving

Author

Erkan, Anil, Babilon, Sebastian, Hoffmann, David, Singer, Timo, Vitkov, Tsoni, Khanh, Tran Quoc, Erkan, Anil, Babilon, Sebastian, Hoffmann, David, Singer, Timo, Vitkov, Tsoni, and Khanh, Tran Quoc

Abstract

The purpose of this work is to determine as a function of velocity the minimal roadway luminance that is required to be judged as being bright enough for a driver to perform a nighttime driving task with an adequate feeling of safety. In this context, it shall also be evaluated which areas of the vehicle forefield are most crucial for the driver’s general brightness perception. A field study with 23 subjects and dimmable LED headlights was conducted, in which the subjects were given the task to assess their perceived brightness for different luminance levels caused by the headlights’ low-beam distribution in the vehicle’s forefield on a 5-step rating scale. The experiments were repeated for three different driving velocities of 0kmh⁻¹ (static case), 30kmh⁻¹, and 60kmh⁻¹, respectively. Results for the static case indicate that, for the roadway to be perceived as bright enough by 50% of the subjects, an average roadway luminance of 0.88 cdm⁻² is required in an area up to 32m in front of the vehicle. Furthermore, a significant effect of driving speed is observed. For example, at 60kmh⁻¹, the luminance must be increased to 1.54 cdm⁻² to be still perceived as sufficiently bright by 50% of the subjects.

Published
2022

23. Association between serum NUCB2/nesfatin‑1 levels and erectile dysfunction.

Author

Koç, Akif, Gul, Abdullah, Erkan, Anil, Guzelsoy, Muhammet, Turkoglu, Ali Riza, Coban, Soner, Kologlu, Rahime Feyza, and Ustundag, Yasemin

Subjects
RECEIVER operating characteristic curves, HIGH density lipoproteins, PROSTATE-specific antigen, IMPOTENCE, BLOOD sugar
Abstract

Erectile dysfunction (ED) is one of the most common complaints in the male sexual health field, with a multifactorial etiology yet to be fully elucidated. Nucleobindin 2 (NUCB2)/nesfatin-1, known for its regulatory role in food intake, can also regulate the vascular, neural and hormonal systems, all of which are of great importance in the etiology of ED. The present study included 43 men with ED and 40 healthy individuals without ED. The participants were assessed using the Turkish version of the International Index of Erectile Function (IIEF-5) to determine the presence and severity of ED. Serum NUCB2/nesfatin-1, total testosterone, fasting blood glucose, hemoglobin A1c, total cholesterol, low-density lipoprotein, high-density lipoprotein, very low-density lipoprotein, triglyceride and total prostate-specific antigen levels were all measured. The mean age of the participants was 46.77±9.87 years with an age range of 25-67 years. The mean ages of the ED and non-ED groups were 47.47±11.19 and 46.03±8.30 years, respectively. Patient age and serum biochemical parameters were found to be comparable between the two groups. The serum NUCB2/nesfatin-1 levels of the ED group were also revealed to be significantly lower compared with those of the non-ED group (P=0.019). There was a weak negative correlation between the serum NUCB2/nesfatin-1 level and the severity of ED according to the IIEF-5 score (r=-0.306; P=0.005). The receiver operating characteristic curve analysis of serum NUCB2/nesfatin-1 revealed a cut-off value of 1.25 ng/ml for distinguishing between the ED and non-ED groups (P=0.019). These findings suggest that reduced serum NUCB2/nesfatin-1 values may be implicated in the etiology of ED. Further studies are required to clarify the effect of NUCB2/nesfatin-1 on vascular physiology and erectile physiology or pathophysiology. [ABSTRACT FROM AUTHOR]

Published
2024
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25. Helligkeits- und Kontrastwahrnehmung bei unterschiedlichen Scheinwerfereinstellungen unter konstanter Straßenbeleuchtung

Author

Wagner, Max, Erkan, Anil, and Khanh, Tran Quoc

Subjects
621.3
Abstract

Innerorts tragen sowohl die Straßenbeleuchtung, als auch die Fahrzeugscheinwerfer zur Beleuchtung der Fahrbahn bei. Die lichttechnischen Anforderungen unterscheiden sich dabei je nach Art der Straße. Die Spannbreite bewegt sich von kleinen Anwohner bis zu großen Hauptverkehrsstraßen. Sowohl Scheinwerfer, als auch Straßenleuchten sind nicht aufeinander abgestimmt. In dem vorliegenden Beitrag soll untersucht werden, inwiefern eine Anpassung des Frontscheinwerfers bei konstanter Straßenbeleuchtung aus Fahrersicht möglich ist. Dazu wurde das Licht eines LED-Scheinwerferpaares eines PKWs gedimmt. Auf unterschiedlichen Straßen wird das Licht der Straßenbeleuchtung dagegen konstant gehalten. Die Probanden sitzen im Fahrzeug, im Gesichtsfeld befinden sich zu bewertende Straßenabschnitte. Die Probanden sollen einschätzen, ob die Helligkeit der Fahrbahnoberfläche für eine sichere Fahrt ausreicht. Außerdem dienen auf der Straße platzierte Detektionsobjekte zur Untersuchung der Kontrastwahrnehmung., Lux junior 2021: 15. Internationales Forum für den lichttechnischen Nachwuchs, 04. – 06. Juni 2021, Ilmenau : Tagungsband, p. 297

Published
2021
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26. Lichttechnische Analyse des deutschen Verkehrsraumes zur Optimierung von Lichtverteilungskurven für Scheinwerfer im Kraftfahrzeug

Author

Hoffmann, David, Erkan, Anil, and Khanh, Tran Quoc

Subjects
621.3
Abstract

Seit Einführung der asymmetrischen Abblendlichtverteilung im Jahr 1957 hat sich die grundsätzliche Lichtverteilung von Kfz-Scheinwerfern kaum verändert. Da sich das Verkehrsbild und die relevanten Straßenparameter, wie die Straßengeometrie oder das Verkehrsaufkommen, seitdem stark verändert haben, eignen sich diese Lichtverteilungen nur bedingt für den Einsatz im heutigen nächtlichen Straßenverkehr. Aktuelle Zusatzfunktionen, wie Autobahn- und Stadtlicht, können bereits in unterschiedlichen Verkehrsräumen aktiviert werden, jedoch fehlen Informationen bezüglich des Verkehrsraumes, die eine vollkommen dynamische Steuerung dieser Lichtfunktionen ermöglichen könnte. Daher besteht eine Notwendigkeit darin, Kenntnis über die lichttechnischen und geometrischen Bedingungen des Verkehrsraumes zu gewinnen. Aus vorherigen und aktuell laufenden Untersuchungen ist der Schwellenkontrast für die sichere Detektion von Objekten im nächtlichen Straßenverkehr bekannt. Um jederzeit eine optimale Ausleuchtung der Fahrbahn und relevanter Objekte zu gewährleisten, ist eine Kenntnis des aktuellen Beleuchtungsniveaus und der Straßengeometrie essenziell. Diese Arbeit präsentiert erste Ergebnisse, benötigte Daten und Methoden zur Datenauswertung des deutschen Verkehrsraumes, um Lichtverteilungen von Kfz-Scheinwerfern zu optimieren., Lux junior 2021: 15. Internationales Forum für den lichttechnischen Nachwuchs, 04. – 06. Juni 2021, Ilmenau : Tagungsband, p. 61

Published
2021
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27. Vergleich von konventionellen H7-Halogenglühlampen und zugelassenen Retrofit-LEDs anhand eines Kfz-Scheinwerfers

Author

Erkan, Anil and Khanh, Tran Quoc

Subjects
621.3
Abstract

LED-Leuchtmittel, die durch ihre Bauform in die Fassungen von konventionellen Leuchtmitteln eingesetzt werden können und somit den Umstieg auf die moderne Lichtquellentechnologie erleichtern, werden Retrofit-LEDs genannt. Im Haushalt erfolgt dieser erleichterte Umstieg auf LEDs bereits seit einigen Jahren. Solch ein Umstieg wäre durch vorhandene Retrofit LEDs auch im Automobilbereich möglich. Aufgrund des hohen Anteils von Fahrzeugen mit Halogen-Scheinwerfern (ca. 56 %) wäre ein Umstieg auf die effizientere LED-Technologie vor allem von energetischem Vorteil. Mittlerweile gibt es in Deutschland Retrofit-LEDs, die für vereinzelte Fahrzeugmodelle zugelassen sind und mit einer Bauartgenehmigung verwendet werden können. Inwieweit diese zugelassenen Leuchtmittel die konventionellen Halogenglühlampen in den Scheinwerfern ersetzen können, wird in dieser Untersuchung betrachtet. Hierzu werden Lichtstärkeverteilungskurven des gleichen Scheinwerfers mit konventionellen H7-Halogenglühlampen und zugelassenen Retrofit-LEDs aufgenommen und verglichen. Die Auswirkungen der verschiedenen Leuchtmittel auf die Lichtverteilung auf der Fahrbahn wird simulativ über die Berechnung der Fahrbahnbeleuchtungsstärke untersucht., Lux junior 2021: 15. Internationales Forum für den lichttechnischen Nachwuchs, 04. – 06. Juni 2021, Ilmenau : Tagungsband, p. 23

Published
2021
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31. Lichttechnische Eignungsprüfung von Retrofit-LEDs als Ersatz für Halogenglühlampen in Kfz-Scheinwerfern

Author

Erkan, Anil, Kobbert, Jonas, Kosmas, Kyriakos, and Khanh, Tran Quoc

Abstract

Die Licht-emittierende Diode (LED) gewinnt sowohl in der Haushalts- als auch in der Kfz-Beleuchtung stetig an Bedeutung. Der Umstieg von konventionellen Glühlampen zu LED-Leuchtmitteln erfolgt bereits seit einigen Jahren durch die Verwendung von sogenannten Retrofit-LEDs im Haushalt. Auch in der Kfz-Frontbeleuchtung wäre solch ein Wechsel technisch möglich. In Deutschland und Europa fehlen derzeit jedoch die rechtlichen Rahmenbedingungen für die Zulassung von Retrofit-LEDs. Dabei könnten sich durch die Verwendung von Retrofit-LEDs sowohl Vor- als auch Nachteile bezüglich der Sicherheit im nächtlichen Straßenverkehr ergeben. So könnte der mögliche höhere Lichtstrom und die kältere Lichtfarbe der Retrofit-LEDs zu einer höheren Leuchtweite und somit einer größeren Sichtbarkeitsweite führen. Diese Eigenschaften könnten jedoch ebenfalls für ein erhöhtes Blendpotential sorgen. Mit der durchgeführten Untersuchung wird eine Aussage bezüglich der Sicherheitserhöhung im nächtlichen Straßenverkehr durch die Verwendung von aktuell verfügbaren Retrofit-LEDs getroffen. Hierfür werden sowohl photometrische Messungen im Labor als auch ein Feldtest durchgeführt und ausgewertet.

Published
2019
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32. İlkokul 4. sınıf sosyal bilgiler dersinde kullanılan eğitsel oyun ve dijital oyun öğretiminin öğrencilerin başarı ve tutumlarına etkisi

Author

Erkan, Anil, Kerimgil Çelik, Seda, and Temel Eğitim Anabilim Dalı

Subjects
Eğitim ve Öğretim, Education and Training
Abstract

Araştırmada, İlkokul 4.sınıf Sosyal Bilgiler dersinde kullanılan eğitsel oyun ve dijital oyun öğretiminin öğrencilerin başarı ve tutumlarına etkisinin araştırılması amaçlanmaktadır. Araştırmanın çalışma grubunu 2018-2019 eğitim-öğretim yılı Elazığ ili Merkez ilçesine bağlı Toki Fırat İlkokulu'nda 4. sınıfa devam eden, deney grubunda 18 öğrenci ve kontrol grubunda 18 öğrenci olmak üzere toplam 36 öğrenci oluşturmaktadır. Deney grubunda eğitsel oyun ve dijital oyun yöntemi, kontrol grubunda da düz anlatım yöntemi uygulanmıştır. Araştırmada nicel araştırma yöntemlerinden deneysel desen ve deneysel desen yöntemlerinde de yarı deneysel desen kullanılmıştır. Uygulama beş hafta sürmüştür. Araştırmada verileri toplamak amacıyla, araştırmacı tarafından geliştirilen Sosyal Bilgiler Başarı Testi ve Demir ve Akengin (2010) tarafından geliştirilen Sosyal Bilgiler Dersine Yönelik Tutum Ölçeği kullanılmıştır. Elde edilen veriler analiz edilirken çözümleme ve yorumlamalarda normallik testleri, ortalama (x̄), standart sapma (ss), frekans, yüzde dağılımları gibi teknikler kullanılmıştır. Normal dağılım gösteren gruplar için İlişkili Örneklemler t-Testi ve Bağımsız Örneklemler T-Testi; normal dağılım göstermeyen gruplar için de Mann Whitney U Testi ve Wilcoxon İşaretli Sıralar Testi kullanılmıştır. Her testi için etki büyüklüğü değeri hesaplanarak sonuca etkisi belirtilmiştir.Araştırma sonuçlarına göre; deney grubu öğrencilerinin başarı testi son test puanları arasında anlamlı bir farklılık tespit edilmiş [p = .000 < .05, t= -6,606] ve kontrol grubu öğrencilerinin başarı testi son test puanları arasında da anlamlı bir farklılık tespit edilmiştir [p= .001 < .05, Z= 3,442]. Ancak deney grubu ve kontrol grubu öğrencilerinin başarı testi son test puanları arasında anlamlı bir farklılık tespit edilmemiştir [p = .885 (p > 0,05), U=157,500]. Araştırma sonuçları öğrencilerin tutumlarına göre incelendiğinde ise, deney grubu öğrencilerinin tutum ölçeği son test puanları arasında anlamlı bir farklılık tespit edilmemiş [p=.102 > .05, Z= 1,635] ve kontrol grubu öğrencilerinin tutum ölçeği son test puanları arasında anlamlı bir farklılık tespit edilmemiştir [p = .881 > .05, t= .152]. Ancak, deney grubu ve kontrol grubu öğrencilerinin tutum ölçeği son test puanları arasında anlamlı bir farklılık tespit edilmiştir [p = .018 < .05, t= 2,475].Öğretmenler, öğrencilerin derse karşı ilgi ve motivasyonun artırmak, süreçte öğrencileri aktif kılmak ve dersleri daha ilgi çekici ve eğlenceli hale getirebilmek için eğitsel oyun ve dijital oyun yöntemlerinden faydalanabilirler. Eğitsel oyun ve dijital oyun yönteminin sadece Sosyal Bilgiler dersinde değil farklı derslerde de rahatlıkla kullanılabileceği söylenebilir. Öğrencileri süreçte aktif hale getirebilecek eğitsel oyun ve dijital oyunlar farklılaştırılarak öğrencilerin bir ürün ortaya çıkarmaları sağlanabilir. In this research, it is aimed to investigate the effect of educational game and digital game teaching used in 4th grade social studies course on students' achievement and attitudes. The study group of the study was attended to 4th grade in Toki Fırat Primary School in the central district of Elazığ in the 2018-2019 academic year, constitute a total of 36 students, including experimental groups 18 students and 18 students in the control group. Educational game and digital game method were used in the experimental group and plain expression method was used in the control group. In the research, experimental design which is one of the quantitative research methods and quasi-experimental design was used in experimental design methods. The application lasted five weeks. In order to collect data, Social Studies Achievement Test developed by the researcher and Attitude Scale towards Social Studies Course developed by Demir and Akengin (2010) were used. While analyzing the data, techniques such as normality values, mean (x̄), standard deviation (ss), frequency and percentage distributions were used in analysis and interpretation. For the normally distributed groups, Related Samples t-Test and Independent Samples T-Test; Mann Whitney U Test and Wilcoxon Signed Ranks Test were used for non-normal distribution groups. The effect size value was calculated for each test and its effect was indicated.According to the results of the research; there was a significant difference between the achievement test posttest scores of experimental group students [p değeri .000 < .05, t= -6,606] and there was a significant difference between the achievement test posttest scores of the control group students [p= . 001 < .05, Z= 3,442]. However, there was no significant difference between experimental group and control group students' achievement test posttest scores. [p= .885 ( p > 0,05 ), U= 157,500]. When the results of the study were examined according to the attitudes of the students, there was no significant difference between the attitude test post-test scores of experimental group students [p = .102 > .05, Z= 1,635] and there was no significant difference between the attitude test post-test scores of the control group students [p = .881 > .05, t=.152]. However, a significant difference was found between the attitude test post-test scores of the experimental and control group students. [ p = .018 < .05, t= 2,475].Teachers can use educational and digital game methods to increase students' interest and motivation towards the lesson, to make them active in the process and to make the lessons more interesting and fun. It can be said that educational and digital game methods can be used not only in Social Studies course but also in different courses. Students are provided with educational games and digital games to uncover a product that can activate in the process of learning students. 156

Published
2019

33. Investigation of effects of nanofluid utilization in automotive radiators on exergetic efficiency of diesel engines

Author

Erkan, Anil, Tüccar, Gökhan, and Nanoteknoloji Mühendisliği Ana Bilim Dalı

Subjects
Exergy analysis, Automotive, Nanoparticles, Engineering Sciences, Radiator, Mühendislik Bilimleri
Abstract

Bu çalışmada, dört zamanlı içten yanmalı motor radyatörüne, etilen glikolve Al2O3, SiO2 ve TiO2 gibi üç farklı çeşit nanoparçacık kullanılarak oluşturulannanoakışkanlar eklenerek konvansiyonel soğutucu akışkanla (saf su)karşılaştırılmıştır. Bu karşılaştırmayı yaparken termodinamiğin ikinci yasasının anakonusu olan ekserji performansları baz alınmıştır. Testler dizel yakıt kullanılarak,sabit 1800 rpm motor hızında gerçekleştirilip, bütün çıktılar deney düzeneğindenelde edilmiştir. İki farklı dispersiyonda (0.2 % ve 0.4 %) toplamda altı adetnanoakışkan testi yapılıp, TiO2 bazlı nanoakışkanın diğer soğutucu akışkanlaragöre ekserjetik açıdan daha iyi performans sergilediği sonucuna varılmıştır. Sonuçolarak bu tezde, saf su ve her bir nanoakışkan için ekserji verimi, ekserji kaybı, ısıekserjisi, iş ekserjisi, egzoz ekserjisi ve entropi üretim oranı gibi tüm ekserjetikçıktılar hesaplanmıştır. In this study, nanofluids formed by using ethylene glycol (EG) and threekinds of nanoparticles such as Al2O3, SiO2 and TiO2 were added to the four-strokeinternal combustion engine radiator and compared with the conventional coolant(pure water). This comparison is based on the exergy performances which are themain theme of the second law of thermodynamics. The tests were carried out at afixed engine speed of 1800 rpm using diesel fuel, and the outputs were obtainedfrom the test setup experimentally. A total of six nanofluid tests were performed ontwo different dispersions (0.2 % and 0.4 %). It was concluded that TiO2 basednanofluid showed better exergetic performance than other coolants. As a result, inthis thesis, exergetic outputs such as exergetic efficiency, exergy destruction,exergy heat, exergy work, exergy total exhaust and entropy production rate werecalculated for pure water and each nanofluid. 67

Published
2018

40. Enerji arzı güvenliği bakımından Avrupa'nın Rusya Federasyonu'na bağımlılığı

Author

Erkan, Anil Çağlar, Batır, Kerem, TR136185, Adnan Menderes Üniversitesi, Sosyal Bilimler Enstitüsü, Uluslararası İlişkiler Anabilim Dalı, and Uluslararası İlişkiler Ana Bilim Dalı

Subjects
Rusya Federasyonu, Pipelines, Enerji Güvenliği, Energy Supply Security, Energy, Yenilenebilir Enerji Kaynakları, Energy Coorperations, International Relations, Enerji Politikaları, Uluslararası İlişkiler, Renewable Energy Sources, Energy Diplomacy, Enerji, Boru Hatları, Energy Security, Enerji Diplomasisi, Enerji Arz Güvenliği, Enerji Şirketleri, Nonrenewable Energy Sources, Russian Federation, Energy Policies, European Union, Avrupa Birliği, Yenilenemeyen Enerji Kaynakları
Abstract

Her geçen gün küresel enerji tüketimi hızla artmaktadır. Enerji kaynaklarının tükenmeye başlamasıyla birlikte yetersiz enerji kaynağı rezervlerine sahip olan ekonomiler enerji ihtiyaçlarını karşılayabilmek amacıyla kaynaklar üzerinde hâkimiyet mücadeleleri ve enerji ithalatına yönelmektedirler. Ekonomilerin enerji ithalatına bağımlı hale gelmesine neden olan enerji kaynakları ithalatına yönelim, enerji güvenliğini son derece olumsuz etkileyen bir durum olarak ortaya çıkmaktadır. Bu bağlamda Avrupa Birliği ve kıta ülkeleri, her geçen gün enerji kaynaklarını diplomatik yaptırım aracı olarak kullanan Rusya Federasyonu?na başta doğal gaz olmak üzere, enerji ithalatına bağımlı hale gelmeye başlamışlardır. Küresel enerji süper gücü olabilmek hedefi doğrultusunda politikalarını belirleyen ve ülke ekonomisi enerji kaynaklarının ihracatından sağlanan gelirlerle büyüyen Rusya Federasyonu, bölge üzerinde, ulusal güvenliğini ve çıkarlarını korumayı amaçlarken, aynı zamanda enerji ihracatının devamlılığının sağlanabilmesi yönünde politikalar belirlemektedir. Bu nedenle, en fazla enerji kaynağı ihracatını gerçekleştirdiği Avrupa kıtası ülkeleriyle işbirliği içerisinde hareket etmeye çalışmakta, aynı zamanda çıkar bölgesi olan yakın çevresinde etkisini kaybetmemek yönünde politikalar izlemektedir. Bu bağlamda, ulusal çıkarların korunması amacıyla Rusya Federasyonu?nun diplomatik yaptırım aracı olarak kullandığı enerji kaynaklarının ve enerji ithalatı bağımlılığının Avrupa ülkelerinin ulusal güvenlikleriyle birlikte, enerji güvenliği üzerindeki olumsuz etkilerin açıklanması tezin amacını oluşturmaktadır. Avrupa ülkelerinin enerji güvenliğinde Rusya Federasyonu?nun politikalarının, boru hatlarının ve enerji şirketlerinin etkisi ve Avrupa ülkelerinin artan bağımlılığa karşılık geliştirdiği politikalar ayrıntılı olarak açıklanmıştır.ANAHTAR SÖZCÜKLER: Enerji Güvenliği, Enerji Arz Güvenliği, Yenilenemeyen Enerji Kaynakları, Avrupa Birliği, Rusya Federasyonu, Enerji Politikaları, Boru Hatları, Enerji Şirketleri, Yenilenebilir Enerji Kaynakları, Enerji Diplomasisi. Each passing day, global energy consumption is increasing rapidly. With shrinking energy sources, economies, which has insufficient energy reserves, are driven into struggles to dominate energy reserves and get obliged to import energy to meet their energy needs. Tendency towards the import of energy sources, which make economies dependent, is an unfavorable situation, which affects energy security negatively. In this scope, European Union and continental countries have begun to be dependent on Russian Federation, which use its energy sources as a diplomatic tool. Russian Federation, which determines its policies so as to be a super power of energy, and whose economy is growing with the income accumulating from the export of energy sources, is conducting policies to keep sustainability of energy export while also aiming to protect its national security and interests in the region. With this reason, while it is conducting policies not to lose its impact over its close neighborhood, where its interests lie, it is also trying to stay in cooperation with European continental countries, where most of its energy exports are transferred. In this scope, the explanation of the impacts of energy resources used as a diplomatic tool by the Russian Federation and the impact of energy import dependency on both national securities of European countries as well as on energy security constitute the main purpose of the thesis. The impact of Russian Federation?s energy policies, of the pipelines and of energy companies as well as the policies developed by European countries as a remedy to their increasing dependency are examined in detail.KEYWORDS : Energy Security, Energy Supply Security, Nonrenewable Energy Sources, European Union, Russian Federation, Energy Policies, Pipelines, Energy Coorperations, Renewable Energy Sources, Energy Diplomacy. 248

Published
2013

44. The Association of Body Composition Parameters Measured by Computed Tomography with Cancer Stage, Prognosis, and Survival in Patients with Renal Cell Carcinoma.

Author

Gur Ozcan SG, Barali D, and Erkan A

Subjects
Humans, Male, Female, Middle Aged, Retrospective Studies, Prognosis, Aged, Muscle, Skeletal diagnostic imaging, Adult, Adipose Tissue diagnostic imaging, Aged, 80 and over, Subcutaneous Fat diagnostic imaging, Length of Stay, Carcinoma, Renal Cell diagnostic imaging, Carcinoma, Renal Cell mortality, Carcinoma, Renal Cell surgery, Tomography, X-Ray Computed methods, Body Composition, Kidney Neoplasms diagnostic imaging, Kidney Neoplasms mortality, Neoplasm Staging
Abstract

Objective: This study aims to investigate the association of preoperative body composition parameters, measured by computed tomography in patients undergoing surgery for renal cell carcinoma, with its stage and to survey the relationship with postoperative hospitalization duration and survival., Methods: Demographic data, pathology results, cancer stages, and hospitalization duration of 104 patients undergoing surgery at the urology clinic due to renal cell carcinoma between 2019 and 2023 were analyzed retrospectively. On computed tomography scans acquired during diagnosis, visceral adipose tissue, subcutaneous adipose tissue, total adipose tissue, and skeletal muscle area were measured. The ratios of body composition parameters were computed., Results: When the correlation between survival time and body composition in deceased patients was analysed, a moderate but significant correlation was observed between skeletal muscle area value and total adipose tissue / skeletal muscle area ratio (r=0.630, p=0.001; r=0.598, p=0.002). A significant and strong correlation was observed between total adipose tissue value and survival (r=0.704, p<0.001). Subcutaneous adipose tissue / skeletal muscle area was found to be an independent risk factor associated with mortality, and a ratio of 0.98 or less increased the mortality risk approximately 16-fold., Conclusion: The relationship between body composition parameters measured by computed tomography, which can be easily evaluated pre-treatment, and mortality, postoperative recovery and length of hospital stay can be evaluated, giving clinicians an idea about the potential difficulties that patients may encounter during the treatment process. For this purpose, the subcutaneous adipose tissue / skeletal muscle area ratio is the most helpful parameter that can be used.

.

Published
2024
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45. Selection for antimicrobial prophylaxis in emergency and elective transurethral procedures: Susceptibility pattern in Türkiye.

Author

Keten T, Balci M, Eroğlu Ü, Özercan AY, Coşer Ş, Başboğa S, Tatlıcı K, Erkan A, Şenel Ç, Salar R, Güzel Ö, Aslan Y, Tuncel A, and Atan A

Subjects
Male, Humans, Female, Adult, Middle Aged, Aged, Retrospective Studies, Anti-Bacterial Agents therapeutic use, Trimethoprim, Sulfamethoxazole Drug Combination, Escherichia coli, Anti-Infective Agents
Abstract

Background: In this study, we aimed to determine the most appropriate antimicrobial agents for prophylactic antibiotic use during emergency and elective transurethral procedures., Methods: The study was conducted in five hospitals located in five different geographical regions of Türkiye. The microorganism cultured in urine before emergency and elective transurethral procedures in these centers between March 2021 and March 2022 were reviewed retrospectively from the hospital records. Demographic data (age and gender) of the patients, comorbid disorders, previous urological procedures, anomalies of the urogenital tract, use of urethral catheters (permanent or clean intermittent catheterization), cultured microorganisms, and antibiotic susceptibilities were noted. The patients hospitalized or had antibiotics for any reason in the previous 1 month were excluded from the study., Results: A total of 1450 patients, 742 men (51.2%) and 708 women (48.8%), were included in the study. The mean age of the patients was 55.3±19.36 (1-98) years. Diabetes mellitus was evident in 271 (18.7%) patients. The five most common microorgan-isms cultured in urine, in order of frequency, were: ESBL (-) Escherichia coli in 418 (28.8%), ESBL (+) E. coli in 309 (21.3%), Klebsiella pneumonia in 183 (12.6%), Enterococcus faecalis in 124 (8.6%), and Pseudomonas aeruginosa in 89 (6.1%). The susceptibility rates to antimicrobial agents recommended for prophylaxis by the American Urology Association and the European Association of Urology guidelines were found as follows: cefepime 87.1%, ampicillin+sulbactam 84%, TMP-SMX 71.6%, amoxicillin+clavulanate 63.5%, cefoxitin 59%, ceftazidime 58.6%, cefuroxime 43.5%, ceftriaxone 43%, and cefixime 38.4%., Conclusion: We found that currently recommended antimicrobials provide poor coverage for the most common pathogens isolated. Urologists should consider patient-based antibiotic prophylaxis in endoscopic urethral procedures, follow appropriate proto-cols, and consider local antibiotic resistance.

Published
2023
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46. Management of Priapism: Results of a Nationwide Survey and Comparison with International Guidelines.

Author

Kalkanli A, Sönmez SZ, Guvel M, Aglamis E, Araz S, Asfuroglu A, Avci HK, Aydin M, Aydos M, Balci U, Baran C, Bastug Y, Baydilli N, Bayrak O, Benlioglu C, Bozkurt IH, Bursali K, Can U, Coser S, Cakici MC, Calik G, Cift A, Cilesiz NC, Demir DO, Demir M, Demirel HC, Dursun M, Demirelli E, Ekenci BY, Eksi M, Ergin G, Ergin IE, Erkan A, Fikri O, Gezmis CT, Gül A, Guzelsoy M, Ibis MA, Inkaya A, Ipekci T, Karakeci A, Karkin K, Kaya C, Kazan O, Kirdag MK, Kizilcay YC, Koseoglu B, Kucuk E, Gonultas S, Ogras MS, Olgun A, Ordek E, Ozbey I, Sarier M, Senel S, Tahra A, Toprak T, Yalcin MY, Yavuzsan AH, Yazar S, Hacıbey İ, Yildirim K, Yilmaz K, Yilmaz S, Yoldas M, Yuce A, Yucel MO, Yuceturk CN, de la Rosette J, and Kadioglu A

Abstract

Objective: The aim of this study is to evaluate current urologic practice regarding the management of priapism in Turkey and compare with international guidelines., Methods: Urologists and urology residents were invited to an online survey consisting of 30 multiple-choice questions on priapism-related clinical practices that were consid- ered most important and relevant to practices by using Google Forms., Results: Total number of responses was 340. Respondents reported that they recorded a detailed patient's medical history and physical examination findings (n = 340, 100%) and laboratory testing, which includes corporal blood gas analysis (n=323, 95%). Participants announced that they performed Doppler ultrasound for 1/4 cases (n = 106, 31%), but 22% of the participants (n=75) replied that they performed in >75% of cases. Participants (n=311, 91%) responded that the first-line treatment of ischemic priapism is decompression of the corpus cavernosum. Moreover, most respondents (n = 320, 94%) stated that sympathomimetic injection drugs should be applied as the second step. About three-quarters of respondents (n = 247, 73%) indicated adrenaline as their drug of choice. Phosphodiesterase type 5 inhibitors seems to be the most pre- ferred drug for stuttering priapism (n=141, 41%). Participants (n=284, 84%) replied that corpora-glanular shunts should be preferred as the first. A large number of par- ticipants (n = 239, 70%) declared that magnetic resonance imaging can be performed in cases with delayed (>24 hours) priapism to diagnose corporal necrosis. Most of the participants (84%) responded that penile prosthesis should be preferred to shunts in cases with delayed (>48 hours) priapism., Conclusion: It would be appropriate to improve the training offered by professional associations and to give more training time to the management of priapism during residency.

Published
2023
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