Modelling Shared Bicycle Demand Using Artificial Neural Networks

Since bicycles are based entirely on muscle power, they are the transportation vehicles with the lowest negative impact on the environment. In addition, since they are an active mode of transportation, they are also named among the leading modes in terms of sustainability. They are also the leading vehicles types among the micromobility systems, which can be considered as small-sized and individual transportation modes, in terms of their historical background as well as purchasing and operating costs. Today, bicycle ridership rates are increasing thanks to the bike-sharing or rental services provided by both local governments and companies in the private sector. Traveling by bicycle, rather than using a motor vehicle, has a positive effect on the natural environment as it does not cause pollutant gas emissions and effects the traffic jams minimally. It is crucial to investigate the periodic changes in the use of shared bicycle systems, especially in order to define the factors that affect this modal shift and to predict the demand for bicycle use in the future. Within the scope of the developed study, the changes in bicycle use and various factors affecting it were investigated in 4 of the cities in which one of Turkey's leading companies in micromobility provides bicycle sharing services. The values regarding bicycle use were then modelled using artificial neural networks. Thanks to the developed model, it will be possible to predict the number of future trips in the cities where bike sharing service is provided and the periodic changes of these trips, as well as to make estimations about the passenger demand that will arise in a city where the new service will be provided.This study has been prepared with the contribution of Yapidrom Technology JSC and with the support from the European Union's H2020 research and innovation programme under the RECIPROCITY Project (Grant NO 101006576)

The Effect of Tympanic Membrane Perforation Site, Size and Middle Ear Volume on Hearing Loss

Objective:The aim of this study was to analyze the location and the size of perforation in cases with tympanic membrane perforation, its relation to the manubrium mallei and middle ear volume, and to investigate how these are correlated with the severity and frequencies of conductive hearing loss.Methods: This prospectively designed study included the patients who presented to the the Department of Otorhinolaryngology at the Dokuz Eylül University with hearing loss or tinnitus complaints in the period from June 2014 through June 2017 and were identified to have tympanic membrane perforation in their otoscopic examination. Patients who underwent myringoplasty and type 1 tympanoplasty and whose air-bone gap was found lower than 10 dB in the postoperative audiological examination were included in the study. Effects of the perforation size, the perforation site, and the relationship of the perforation with the manubrium, as well as the effects of the middle ear volume on the severity and frequency of conductive hearing loss were compared.Results: The study included 44 ears of 38 patients (13 male and 25 female) of whom six had tympanic membrane perforation in both ears. Air conduction threshold and air-bone gap were significantly found higher if the perforation area was wide (p<0.05), the perforation involved both the anterior and the posterior quadrants (p<0.05), had contact with the manubrium mallei (p<0.05), and the middle ear volume reduced (p<0.05).Conclusion: Solely tympanic membrane perforation affects hearing function; nevertheless, hearing function are better in cases, which have perforations small in size, no contact with manubrium mallei and well pneumatized middle ears

Evaluation of the efferent system with contralateral suppression in auditory neuropathy spectrum disorder

Amaç: İşitsel nöropati spektrum bozukluğunun (ANSD) medial olivokoklear efferent sistem aktivitesi üzerine olan etkilerini anlık uyarılmış otoakustik emisyon (TEOAE) ve kontralateral supresyon (KLS) kullanarak değerlendirmek amaçlandı. Gereç ve Yöntemler: TEOAE yanıtları 2 gruba ayrılmış 48 kulakta kaydedildi. İşitsel nöropati grubundan 24 kulağı (ortalama 51,2 ay), kontrol grubu ise 24 kulağı (ortalama 55,9 ay) araştırmaya dahil edildi. Her iki grubun TEOAE ölçümleri karşı kulakta gürültülü (geniş band gürültü, 60 dB SPL şiddetinde) ve gürültüsüz olarak kaydedildi. Bulgular: ANSD ve kontrol grupları arasında kontralateral supresyon değerleri karşılaştırıldığında, istatistiksel olarak anlamlı fark gözlendi. KLS sonrası kontrol grubunun değerleri, öncekinden istatistiksel olarak anlamlı derecede düşüktü. ANSD grubunun KLS öncesi ve sonrası TEOAE sinyal-gürültü oranları (SNR) karşılaştırıldığında, ölçülen frekanslarda istatistiksel olarak anlamlı bir fark gözlenmedi. Sonuç: ANSD olgularında KLS uygulandığında anlamlı bir supresyon gözlenmemektedir. Kontrol grubunda KLS uygulandığında ise istatistiksel olarak da anlamlı supresyon görülmektedir. İşitsel nöropatili olgularda supresyon gözlenmemesi, efferent sistemin işlevsel olmamasından kaynaklanabileceği gibi hem afferent hem de efferent sistemin işlevselliğini yitirmesine bağlı olabilir. KLS, işitsel nöropatinin tanısında kullanılabilecek bir test bataryası olarak değerlendirilebilir. Ancak, işitsel nöropati tanısında kullanımına ilişkin daha fazla araştırmaya ihtiyaç vardır.Objective: It was aimed to examine the effects of Auditory Neurophaty Spectrum Disorder (ANSD) on medial olivocochlear efferent system activity by using Transient Evoked Otoacoustic Emission (TEOAE) and Contralateral Suppression (CLS). Material and Methods: TEOAEs were recorded in a total of 48 ears, divided into two groups. Twenty-four ears of the ANSD group (mean 51.2 months) and 24 ears of the control group (mean 55.9 months) were included in the study. TEOAE measuremens of both groups were recorded with (broadband noise, 60 dB SPL) and without noise in the contralateral ear. Results: When the contraateral supression values were compared between the ANSD and control groups, statistically significant difference was observed. The values of the control group after CLS were statistically significantly lower than before. When the TEOAE signal-to-noise ratios (SNR) of the ANSD group before and after KLS were compared, no statistically significant difference was observed in the measured frequencies. Conclusion: No significant suppression effect was found when CLS is performed to patients with ANSD. The absence of suppression in the ANSD grup may be due to the non-functionality of the efferent system as well as the loss of functionality of both afferent and efferent system. CLS can be considered as a test battery that may be used in the diagnosis of auditory neuropathy. However, there is need further research on its use in the diagnosis for auditory neuropathy

Effect of Korean Red Ginseng on Noise-Induced Hearing Loss

Objective:Noise-induced hearing loss (NIHL) is one of the most important problems affecting both social and professional life of patients. There is no treatment method considered to be successful on the hearing loss that has become a permanent nature. Aim of this study is to evaluate protective effect of Korean Red Ginseng (KRG) against NIHL in an animal model.Methods:Twenty-eight rats were separated into four groups [control saline (group I), control KRG (group II), saline + noise (group III), KRG + noise (group IV)]. Rats in the saline and KRG groups were fed via oral gavage with a dose of 200 mg/kg/day throughout for 10 days. Fourteen rats (group III and IV) were exposed to 4 kHz octave band noise at 120 dB SPL for 5 hours. Hearing levels of rats were evaluated by distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) at 4, 8, 12, 16 and 32 kHz frequencies prior to and on days 1, 7 and 10 after the noise exposure. Rats were sacrificed on 10th day, after the last audiological test. Cochlea and spiral ganglion tissues were evaluated by light microscopy.Results:Audiological and histological results demonstrated that after noise the group IV showed better results than group III. In the noise exposed groups, the most prominent damage was seen at the 8 kHz frequency region than other regions. After the noise exposure, DPOAE responses were lost in 1st, 7th and 10th measurements in both group III and IV. Thus, we were not able to perform any statistical analyses for DPOAE results.Conclusion:Our findings suggest that KRG seems to be an efficient agent against NIHL. There is need for additional research to find out about the mechanisms of KRG’s protective effect

HAVALİMANLARINA ERİŞİM İÇİN TÜREL SEÇİM DAVRANIŞI: İSTANBUL ATATÜRK ULUSLARARASI HAVALİMANI (IST) VE SABİHA GÖKÇEN ULUSLARARASI HAVALİMANI (SAW) ÖRNEĞİ

Accessing airports has been a problem for passengers due to traffic congestion in cities. Thus, in order to catch the flights on time, passengers consider many factors to choose the transportation mode for airport access. Some of the factors are covariates, and they can be listed as age of the passenger, number of luggage carried, travel cost and travel time to the airport, group size of the passengers, and reliability of access modes. These covariates, may differ for each airport; and hence, in this paper, we investigated the differences of these covariates between Istanbul Ataturk International Airport (IST) and Istanbul Sabiha Gokcen International Airport (SAW). Analysis of Variance (ANOVA) and post-hoc tests were conducted to investigate the covariates that affect the mode choice to access IST and SAW. The results indicated that these two airports have differences in terms of the effect of these selected six covariates on airport access mode choice. Reliability of the modes, travel time, travel cost, age of the passenger and traveling group size affected the mode choice to access IST. On the other hand, only reliability of the modes, travel time and travel cost had effects on airport access mode choice for SAW. Based on the analysis, some recommendations for the decision makers were also provided.Şehirlerde trafik sıkışıklığından dolayı havalimanlarına erişim bir sorun haline gelmiştir. Bu yüzden, yolcular havalimanlarına erişimdeki ulaşım türü seçimlerinde uçuşlarını kaçırmamak adına birçok faktörü değerlendirmektedir. Bu faktörlerin bazısı yolcunun yaşı, beraber seyahat ettiği kişi sayısı, bagaj sayısı, havalimanına yaptığı seyahatin maliyeti ve süresi ile ulaşım türünün güvenirliğidir. Bu faktörler havalimanları arasında farklılık gösterebilir. Dolayısıyla, bu çalışmada, sözü edilen faktörlerin farkı İstanbul Atatürk Uluslararası Havalimanı (IST) ve İstanbul Sabiha Gökçen Uluslararası Havalimanı (SAW) arasında incelenmiştir. Bu inceleme, Varyans Analizi (ANOVA) ve ona ait post-hoc testleri ile yapılmıştır. Sonuçlara göre, havalimanına erişimde kullanılan ulaşım türlerinin seçimini etkileyen faktörler hususunda bu iki havalimanı arasında farklılıklar mevcuttur. Ulaşım türlerinin güvenirliliğinin, seyahat süresinin, seyahat maliyetinin, yolcunun yaşının ve yolcuyla beraber seyahat eden kişi sayısının, IST’a erişim için ulaşım tür seçiminde etkili olduğu ortaya çıkmıştır. Ancak SAW’a erişim için sadece ulaşım türü güvenirliliği, seyahat süresi ve seyahat maliyeti tür seçiminde etkin olmuştur. Analizin sonuçlarına bağlı olarak, karar verici merciiler için bazı tavsiyelerde bulunulmuştur

Organizational commitment: Organizational climate's effect on organizational commitment and research of the relationship between organizational climate and organizational commitment in Trakya University

Yüksek Lisans Tezi1960 lardan beri örgütsel baglılık, hem yöneticiler hem de arastırmacılar için en ilgi çekici konulardan biri olmaya devam etmektedir. Bir çok çalısma, örgütsel baglılıgın is bırakma ve performans gibi sonuçlarını arastırmak için gerçeklestirilmektedir. Örgütsel baglılık çalısanın örgüt ile iliskisini niteleyen psikolojik bir durumdur. Bu psikolojik durum örgüte üyeliginin devamı konusunda büyük bir etkiye sahiptir. Baglı bir çalısan, örgütü etkileyen herhangi bir iyi veya kötü durumda örgütte kalan bireydir. Örgüt iklimi örgütsel kosulları, çalısanları ve yönetim uygulamalarını içeren dinamik bir etkilesim sürecinin yansımasıdır. Algılanan örgüt iklimi motivasyonu uyandırır ve tatmin, üretkenlik veya performans, örgütsel baglılık ve is bırakma gibi örgüt için çesitli sonuçlar doguran davranıslara sebep olur. Bu çalısmada, örgüt iklimi ve örgütsel baglılık arasındaki iliski ile ilgilenmekteyiz. Örgüt iklimi ve örgütsel baglılık arasındaki iliskiyi kavrayabilmek için, ilk asamada literatür arastırması yürütülmüstür ve ikinci asamada Trakya Üniversitesi'nde amprik bir çalısma uygulanmıstır. Bilgiler bir anket vasıtasıyla toplanmıstır. Anket sosyo-demografik, örgüt iklimi ve örgütsel baglılık bölümleri olmak üzere üç bölümden olusmaktadır.Since the 1960s organizational commitment continues to be one of the most interesting issues for both managers and researchers. Many studies have attempted to explore its effect on work outcomes such as turnover and job performance. Organizational commitment is a psychological state that characterizes the employee's relationship with the organisation. This psychological state has big effects in terms of continuing his or her membership in the organization. A committed employee is one who stays with the organization under any favorable or unfavorable circumstances affecting the organization. Organization climate is a reflection of a dynamically interacting process involving organizational conditions, internal employees, and management practices. The perceived organizational climate can arouse motivation and cause behaviour, which results in various consequences for the organization such as: satisfaction, productivity or performance, organizational commitment and turnover. In this study, we are interested in the relationship between organizational climate and organizational commitment. To apprehend the relationship between organizational climate and organizational commitment, a literature survey was conducted in first stage, and an amprical study was applied in Thrace University in second stage. Data were collected by using a questionnaire. The questionnaire consisted of three part as socio-demographic, organizational climate survey and organizational commitment survey

Mode choice behavior modeling of ground access to airports: A case study in Istanbul, Turkey

Günay, Gürkan (Dogus Author)The increase in air transportation mode share, thereby the passenger traffic at airports has made the ground access to the airports more important in recent years. The aim of this study is to analyze the ground access mode choice to airports by using Multinomial Logit (MNL). In particular, our focus is on how transit areas of influence affect the mode choice for travelling to airports. Ataturk International Airport (IST) in Istanbul, Turkey was selected for the analyses and the investigated modes to access IST were automobile, drop-off, public transit, and taxi. The results showed that significant factors and variables included the trip distance to access IST, type of destination, trip cost to IST, automobile ownership status, employment status, travelling group size, location of the trip origin with respect to public transit influence, and time difference between the flight time and departure time to IST. It is also concluded that if the trip origin to IST was inside the influence areas of public transit, then public transit would be more likely to be chosen over other modes for accessing IST

Congestion pricing implementation in Taksim zone: a stated preference study

Günay, Gürkan (Dogus Author) -- Conference full title: 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest; Hungary.Implementation of Congestion Pricing, which is one the mechanisms of transportation demand management, has so far been successfully used throughout the world. In this study, it was aimed to measure the applicability of Congestion Pricing concept in Istanbul, Turkey. Taksim district of Istanbul was proposed as the implementation area. This is because high levels of congestion are being observed in Taksim. To understand responses of residents living in Yesilkoy (Istanbul) data are collected using stated preference surveys. Yesilkoy is chosen since it is close to the Istanbul Ataturk International Airport (IST) and hence is considered as a transfer point between IST and Taksim. Many trips between IST and Taksim involve the usage of the express jitneys between Yesilkoy and Taksim. Moreover, Yesilkoy is mainly a residential area and generate high number of jitney trips. Travel patterns and behavior of residents in Yesilkoy and attitudes towards Congestion Pricing are investigated

Conditional freight trip generation modelling

Günay, Gürkan (Dogus Author)Freight Trip Generation (FIG) in general and FTG modelling in particular are fields that are not concentrated upon as much as passenger trip generation. Therefore, the main objective of this work was to improve the understanding of the underlying processes that generate freight trips and through this understanding, to improve the modelling of FIG. To achieve this goal, the authors first had an extensive literature review to understand the reasons for the weaknesses of the current FTG modelling approaches. After identifying these weaknesses, some of them were brought to a focus in this work. One of the main weaknesses was the inadequacy of the classification system which was used to group commercial establishments in a set of standardized classes. Hence, firstly an experiment was conducted to create groups of logistical sites that had homogeneous FTG characteristics. It was observed that one of these segments had too many zero trips for a particular vehicle category, namely tractor trailers. Then, to solve this problem, a new 'conditional' modelling approach for FTG modelling of this group and this vehicle category was proposed and tested using the data obtained from Kocaeli City Logistics Master Plan. This new hypothesised conditional approach aimed to find the probability of the segment generating tractor-trailer trips using the binary logit model and the generated trips given that the sites produced tractor trailer trips using the regression technique. Afterwards, the models developed using the new approach were compared with the models obtained using only the common modelling approach of the regression analysis. The results indicated that creating homogeneous groups of logistical sites was possible and the new conditional modelling approach which was applied to one segment of the logistical sites for FTG of tractor-trailers, performed better than the regular regression modelling. Lastly, some recommendations for further improvement of this modelling approach were provided