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Multi-objective optimal sizing and techno-economic analysis of on- and off-grid hybrid renewable energy systems for EV charging stations
No full textIntegrating electric vehicle charging stations (EVCSs) with renewable energy systems requires the consideration of several factors during the planning stage, including environmental impact, economic viability, grid reliability, and self-sufficiency. Therefore, this study conducts a multi-objective optimal sizing of on- and off-grid hybrid renewable energy systems for EVCSs. The sizing problem is solved using the Non-dominated Sorting Genetic Algorithm (NSGA-II). Subsequently, the best suitable solutions from the obtained non-dominated solutions are selected using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method, prioritizing the objective functions based on diverse interests of different stakeholders (large and small private investors and governmental entities). Finally, a techno-economic analysis is made considering payback period, profitability index (PI), and internal rate of return (IRR). The results show that on-grid systems show high economic viability with payback periods between 1.98 and 7.72 years, an average PI of 5.07 and an average IRR of 23.97%. Although off-grid systems present lower economic viability with payback periods between 8.77 and 22.42 years, an average PI of 1.68 and an average IRR of 4.91%, in certain cases they reach investable levels with payback periods below 10 years, PI above 2, and IRR above the interest rate.Scientific Research Projects Department of Istanbul Technical University [MDK-2022-43623]The authors would like to thank the Republic of Tuerkiye, the Ministry of Transport and Infrastructure, and the staff of the General Directorate of Highways (KGM) for providing the data used in this study. This work was supported by the Scientific Research Projects Department of Istanbul Technical University. Project Number: MDK-2022-43623
Türk firmalarının sürdürülebilirliğinin uluslararası standartlara uygun olarak modellenmesi ve gereksinimleri
No full textSürdürülebilirlik günümüzde gün geçtikçe daha önem kazanan bir terim olmaya başlamıştır. İşletmelerin sürdürülebilir olması için sürdürülebilirlikle ilgili faaliyetlerinin raporlanması dünya çapında yasal olarak zorunluluk haline gelmektedir. Bu sebepten ötürü sürdürülebilirlik raporlama ekosistemi devamlı değişmektedir. Bu tez çalışması bu değişime ayak uydurmaya çalışan Türkiye'ye özel ve küresel sürdürülebilirlik raporlama standartlarının durumunu ve uyumunu içerik analize yöntemi ile değerlendirmiştir. Tez çalışması Türkiye'ye özel olan sürdürülebilirlik raporlama standartları hakkında bir değerlendirmelerde ve gerekli yerlerde tavsiyelerde bulunmuştur.Sustainability is a term that is becoming constantly more relevant. For businesses to become more sustainable sustainability reporting activities are becoming globally mandatory. For this reason sustainability reporting ecosystem is constantly changing. Using a content analysis method this thesis work has evaluated the situation and compatibility of Turkish and global sustainability reporting frameworks that are constantly trying to adjust to this change. This thesis work has provided an evaluation and appropriate recommendations on Turkish sustainability reporting standards
Bourdieu’nün sermaye teorisi bağlamında Türkiye’den Almanya’ya göç eden akademisyenlerin perde arkası: Nitel bir çalışma
Get PDFIn dieser Masterarbeit wurde eine Untersuchung über Akademiker durchgeführt, die in der Türkei geboren und aufgewachsen sind und sich während ihrer Tätigkeit als Mitarbeiter einer Universität in der Türkei für eine Migration nach Deutschland entschieden haben. Unter Verwendung des konzeptionellen Rahmens von Pierre Bourdieu zielt die Studie darauf ab, den ökonomischen, kulturellen, sozialen und symbolischen Kapitalstatus von Akademikern in der Türkei und in Deutschland aufzuzeigen. Der Fokus der Studie liegt auf der Art und Weise, wie die Stichprobe ihr kulturelles Kapital vor und nach der Migration nutzen kann, sowie auf den Funktionen ihres sozialen Kapitals. Die Studie ist das Ergebnis einer qualitativen Forschung mit der Technik des Tiefeninterviews. Im Rahmen der Studie wurden 7 Akademiker befragt, die nach 2015 aus der Türkei nach Deutschland migriert sind. Der Grund für die Beschränkung auf das Jahr 2015 ist die zunehmende Tendenz der Migration zwischen der Türkei und Deutschland im Jahr 2015. Den Forschungsergebnissen zufolge wanderten einige der Befragten aus, um ihren Lebensstandard zu verbessern, während andere aufgrund von politischem Druck auswanderten. Es wurde festgestellt, dass die Befragten, die alle über ein hohes kulturelles Kapital verfügten, der Meinung waren, dass ein gewisses Maß an sozialem Kapital erforderlich sei, um in der Türkei in Positionen arbeiten zu können, die ihrem kulturellen Kapital entsprechen. Andererseits wurde beobachtet, dass sie in Deutschland, obwohl sie noch nicht so viel soziales Kapital wie in der Türkei aufgebaut hatten, nur mit ihrem kulturellen Kapital einen Arbeitsplatz finden konnten. Es zeigte sich, dass die Befragten, die ihr soziales Kapital in der Türkei auf kumulative Weise und von Menschen, die ihnen ähnlich waren, aufgebaut hatten, aufgrund von sprachlichen und kulturellen Unterschieden die größten Schwierigkeiten hatten, soziale Netzwerke in Deutschland aufzubauen. Es wurde festgestellt, dass keiner der Befragten, die angaben, dass die unzureichende Anerkennung ihres in der Türkei erworbenen Kapitals eine Rolle bei ihrer Entscheidung zur Migration spielte, erwägt, zurückzukehren.Bu yüksek lisans tezinde Türkiye’de doğup büyüyen ve Türkiye’de bir üniversitede kadrolu çalışırken Almanya’ya göç etme kararı almış akademisyenler üzerine bir araştırma gerçekleştirilmiştir. Çalışma Pierre Bourdieu'nün kavramsal çerçevesini kullanarak, akademisyenlerin Türkiye’de ve Almanya'daki ekonomik, kültürel, sosyal ve sembolik sermaye durumlarını ortaya çıkarmayı amaçlamaktadır. Çalışmanın odağında örneklemin göç öncesi ve göç sonrası kültürel sermayesini kullanabilme yolları ve sosyal sermayesinin işlevleri yer almaktadır. Çalışma derinlemesine görüşme tekniğinin kullanıldığı niteliksel bir araştırmanın ürünüdür. Çalışma kapsamında 2015 yılından sonra Türkiye’den Almanya’ya göç etmiş olan 7 akademisyen ile görüşülmüştür. 2015 yılı sınırlandırmasının sebebi Türkiye Almanya göç hattında 2015’te görülen ivmedir. Araştırmada elde edilen bulgulara göre görüşülenlerin bir kısmı yaşam standartlarını iyileştirme amaçlı göç etmiş, bir kısmı da siyasi nedenlerden bir baskı hissederek göç etmiştir. Hepsi yüksek kültürel sermayeye sahip olan görüşülenlerin Türkiye’de bu sermayelerine uygun pozisyonlarda çalışabilmek için belirli bir sosyal sermayeye sahip olmak gerektiği düşüncesi taşıdığı görülmüştür. Öte yandan Almanya’da ise henüz Türkiye’deki kadar bir sosyal sermaye oluşturmamış olmalarına rağmen sadece kültürel sermayeleri ile iş bulabildikleri görülmüştür. Türkiye’de sosyal sermayelerini kümülatif bir şekilde ve kendilerine benzeyen insanlardan oluşturmuş olan görüşülenlerin Almanya’da sosyal ağlar kurarken en çok dil ve kültür farklılığından zorluklar yaşadıkları ortaya çıkmıştır. Türkiye’de biriktirdikleri sermayelerinin karşılığını alamamalarının göç etme kararlarında rol oynadığını belirten görüşülenlerin hiçbirinin geri dönmeyi düşünmedikleri tespit edilmiştir
Structural properties of rat intestinal fatty acid-binding protein with its dynamics: Insights into intrinsic disorder
No full textBackground: The rat intestinal fatty acid-binding protein (I-FABP) is expressed in the small intestine and is involved in the absorption and transport of dietary fatty acids. It is used as a marker for intestinal injury and is associated with various gastrointestinal disorders. I-FABP has been studied extensively using conventional experimental and computational techniques. However, the detection of intrinsically disordered regions requires the application of special sampling molecular dynamics simulations along with certain bioinformatics because conventional computational and experimental studies face challenges in identifying the features of intrinsic disorder. Methods: Replica exchange molecular dynamics simulations were conducted along with bioinformatics studies to gain deeper insights into the structural properties of I-FABP. Specifically, the C? and H? chemical shift values werecalculated, and the findings were compared to the experiments. Furthermore, secondary and tertiary structure properties were also calculated, and the protein was clustered using k-means clustering. The end-to-end distance and radius of gyration values were reported for the protein in an aqueous solution medium. In addition, its disorder tendency was studied using various bioinformatics tools. Results and Conclusion: It was reported that I-FABP is a flexible protein with regions that demonstrate intrinsic disorder characteristics. This flexibility and intrinsic disorder characteristics of IFABP may be related to its nature in ligand binding processes
Remineralization potential of a novel varnish: an in vitro evaluation
No full textDespite fluoride's widespread use in preventing dental caries, it remains a significant oral disease with some drawbacks. Consequently, new preventative agents have emerged that can function independently of fluoride. Our aim is to demonstrate the efficacy of newly developed varnishes, 3% Rennou (theobromine calcium and phosphate) and 1% Rennou, in remineralizing initial caries. In our experiment, 40 human enamel samples were randomly allocated into four groups of 10 samples each as: Group 1 (G1): 5% NaF (Colgate PreviDent (R)), Group 2 (G2): 1% Rennou (R), Group 3 (G3): 3% Rennou (R) and Group 4 (G4): Casein Phosphopeptide-Amorphous Calcium Phosphate + Fluoride (MI Varnish (TM) GC). To produce an artificial carious lesion in the enamel, the samples were kept in a demineralizing solution for 72 hours. Samples underwent pH cycling for 6 days in order to induce remineralization. The means of the three measurements were compared, and the percentage of Surface Microhardness Recovery in (SMHR%) was calculated. Scanning Electron Microscopy (SEM) was used for qualitative assessment of surface changes. G1 had the highest SMHR% value, followed by G3, G2 and G4. The One-way ANOVA (Analysis of Variance) showed significant differences in the SMHR% values among the groups after six days of cycling (p < 0.001). In pairwise comparisons, groups did not show differences in means of SMHR% except for G1 and G4 (p = 0.006). In the SEM Images, after treatment within the NaF group, many flaky sediments were found on the enamel surface. Similarly, the maximum mineral gain was seen in the NaF and Rennou groups. SEM images of both varnish surfaces revealed a uniform layer interspersed with shapeless precipitates. All varnishes treated artificial enamel lesions to varying degrees. However, both concentrations of Rennou showed remineralization potential comparable to 5% NaF in acceptable statistical measurements. Thus, it could be used as a potentially effective preventive measure for pediatric patients
Corporates' responsibility to respect human rights
No full textBağlayıcı hukuk normları ve yaptırımları incelendiğinde uluslararası hukukun birincil aktöru?nu?n halen devletler olduğu gözlemlenmektedir. Bununla birlikte özellikle 1970 sonrası neoliberal ekonomik politikalar sonucu hızla bu?yu?yerek ulus ötesi yayılım sergileyen çok uluslu şirketler uzun zamandır ekonomik bakımdan birçok u?lke ile rekabet edebilecek gu?çtedir ve gu?nu?mu?zde bu rekabetin toplumsal olarak da önem arz ettiği söylenebilecektir. Sahip olduğu gu?ç kapsamında insan haklarını tehdit eden şirketlerin bu konuya ilişkin sorumluluklarının belirlenmesi ihtiyacından dolayı uluslararası örgu?tler tarafından bir dizi kılavuzlar yayınlanarak iş du?nyası ve insan hakları ilişkisinin çerçevesi çizilmiştir. Bu uluslararası belgeler, şirketlerin özen yu?ku?mlu?lu?ğu? kapsamında insan hakları durum tespiti su?reci yu?ru?tu?lmesi ve olumsuz etkilerin önlemesi veya azaltması amacıyla etki gu?cu? kullanılması gibi yeni kavramlara yer vermesi bakımından önem arz etmektedir ancak nihayetinde birer yumuşak hukuk kuralı olarak şirketlerin sebep olduğu insan hakları ihlallerinin önlenmesi ve telafisi konusunda tek başlarına yetersiz kalacaklarını belirtmek isteriz. Yakın geçmişte meydana gelen endu?striyel ve çevresel felaketler ile ku?resel ekonomik ve sağlık krizlerinin ortaya çıkardığı tablo şirketlerin gönu?llu?lu?k esasına dayanan davranışlarının insan hakları ihlallerini azaltmakta etkili olamadığını ortaya koymuştur. Bunun farkına varan u?lkeler, şirketlerin tedarik zincirinde yer alan insan hakları meselelerini ele almasını zorunlu kılacak du?zenlemeleri kabul etmişlerdir. Avrupa Birliği'nde birçok u?ye devlet mevzuatında bu yönde değişiklikler gerçekleştirmiş olup çok yakın tarihli direktif uyarınca önu?mu?zdeki dönemde tu?m u?ye devletlerin şirketlerin hesap verebilirliğine yönelik bağlayıcı kuralları yasalaştırması gerekmektedir. Hiç şu?phesiz bu yasalar yalnızca yu?ru?rlu?kte olduğu u?lkeyi değil ticari ilişkilerin bulunduğu tu?m u?lkeleri etkileyecektir. İşbu çalışmada, sosyal alandan sıyrılarak hukuki bir zemine oturtulmaya çalışılan şirketlerin insan hakları alanındaki sorumlulukları ele alınmıştır.When binding legal norms and penalties are analyzed, it is observed that states are still the primary actors in international law. However, as a result of neoliberal economic policies, particularly after 1970, multinational corporations that have rapidly grown and expanded transnationally have long been economically capable of competing with many countries, and it can be said that this competition is also socially significant today. Due to the need to determine the responsibilities of companies that threaten human rights within the scope of their power, a series of guidelines have been published by international organizations to outline the framework of the relationship between business and human rights. These international instruments are remarkable as they introduce new concepts such as conducting human rights due diligence processes and using leverage to prevent or mitigate adverse impacts on human rights within the scope of corporations' duty of care. However, it should be noted that, as soft law rules, they will be insufficient on their own to prevent and remedy human rights violations caused by companies. The recent industrial and environmental disasters, which have led to severe consequences, global economic and health crises, and their impacts, have shown that corporations' ethical and social responsibilities based on voluntarism are ineffective in reducing human rights violations. Recognizing this, many countries have adopted regulations that require companies to address human rights issues within their supply chains. In the European Union, many member states have amended their legislation in this direction, and according to a very recent EU directive, all member states will be required to adopt binding rules on corporate accountability in the coming period. Undoubtedly, these regulations will have an impact not only in the country where they are enforced but also in all countries where commercial relations exist. This study addresses the responsibilities of corporations on human rights, which are attempted to be shifted from the social sphere and be grounded on a legal basis
Oil-in-Water Emulsions Probed Using Fluorescence Multivariate-Curve-Resolution Spectroscopy
No full textHydrophobic surfaces in contact with aqueous media are omnipresent in nature. A plethora of key biological and physiological processes occur at the interface of immiscible fluids. Besides its fundamental importance, probing such interfaces is rather challenging, especially when one medium is bathed in the other. Herein, we demonstrate a fluorescence-based method that probes the oil-water interface and interfacial processes through surface dielectric perturbations. The fluorescence response of Nile Red is measured in hexadecane in water nanoemulsions. Three major spectral components appear: two from the bulk liquid media (hexadecane and water) and a distinct band at around 640 nm due to the interfacial component. Such spectra are deconvoluted using the multivariate-curve-resolution algorithm, and interface-correlated fluorescence spectra are attained. The influence of anionic sodium dodecylbenzenesulfonate (SDBS) and cationic cetyltrimethylammonium bromide (CTAB) surfactants on the oil-water interface is elucidated with concentration-dependent measurements. A charge-dependent spectral shift is observed. The interface correlated band at 641 nm for bare hexadecane nanoemulsions red shifts in the presence of anionic surfactants, indicating an apparent dielectric increase. In contrast, the same band gradually blue shifts with increasing cationic surfactant concentration, indicating an apparent interface dielectric decrease. Such a method can be utilized to probe alterations at interfaces beyond the oil/water interface.T?rkiye Bilimler Akademisi; TUBA-GEBIP Outstanding Young Investigator Award; Science Academy BAGEP Young Scientist AwardsThis work was supported by the TUBA-GEBIP Outstanding Young Investigator Award and the Science Academy BAGEP Young Scientist Awards. We sincerely thank Prof. Sylvie Roke for fruitful discussions and Laboratory for Fundamental BioPhotonics at EPFL to allow us to perform data acquisition of the early stages of this study
Imprinted Polymers on the Route to Plastibodies for Biomacromolecules (MIPs), Viruses (VIPs), and Cells (CIPs)
No full textAround 30% of the scientific papers published on imprinted polymers describe the recognition of proteins, nucleic acids, viruses, and cells. The straightforward synthesis from only one up to six functional monomers and the simple integration into a sensor are significant advantages as compared with enzymes or antibodies. Furthermore, they can be synthesized against toxic substances and structures of low immunogenicity and allow multi-analyte measurements via multi-template synthesis. The affinity is sufficiently high for protein biomarkers, DNA, viruses, and cells. However, the cross-reactivity of highly abundant proteins is still a challenge
CEO mesajlarındaki izlenim yönetimi taktikleri üzerine bir literatür araştırması A literature review on impression management tactics in CEO messages
Get PDFGünlük yaşamda bireyler, sosyal çevrelerindeki insanların kendileri hakkındaki düşüncelerini etkileyebilmek için farklı davranış biçimleri sergileyebilmektedirler. Bu durum kişisel yaşamda olduğu kadar iş yaşamında da görülmekte ve çalışanlar bireylerin kendileri hakkındaki izlenimlerini etkileyebilmek için çeşitli taktiklere başvurmaktadırlar. Üst düzey yönetime bakıldığında ise CEO’lar, şirketlerini temsil etmekte ve ilgilileri tarafından takip edilmektedirler. CEO’ların açıklamalarının gerek iç gerekse dış paydaşlar üzerindeki etkileri dikkate alındığında, mesajlarında yer alan izlenim yönetimi taktikleri izleyicilerin şirket hakkındaki düşüncelerini etkilemede önemli bir rol oynayabilmektedir. Bu nedenle çalışmada, CEO’ların metinlerinde yer alan izlenim yönetimi taktilerini belirlemeye yönelik bir literatür araştırması yapılması hedeflenmiştir. Konu ile ilgili incelenen yirmi dokuz makale sonucunda CEO’ların kişilik ve demografik özelliklerinin, kurucu olma statülerinin, tanınırlıklarının ve kültürlerinin CEO’ların izlenimlerini nasıl yönettikleri üzerinde etkili olduğu görülmektedir. Bununla birlikte izlenim yönetimi kriz dönemlerinde paydaşlarla iletişimde, finansal analistlerin tahmin davranışlarını etkilemede ve CEO’ların görevden ayrılma ihtimallerine ilişkin takipçilere fikir sunmada rol oynamaktadır. Ayrıca CEO’ların mesajlarının yer aldığı raporların türü ve şirketin performansına göre de izlenim yönetimi taktikleri farklılaşabilmektedir. Araştırmalar aynı zamanda CEO’lar ve yönetim kurulu başkanları tarafından yazılan mesajlardaki benzerlikleri ve farklılıkları da ortaya çıkarmaktadır. Çalışmalar incelendiğinde, CEO’ların açıklamalarında yer alan sürdürülebilirlik ve entelektüel sermaye gibi konuların yanı sıra olumsuz ifadelerin de izlenim yönetimi kapsamında ele alındığı görülmektedir.In daily life, individuals can exhibit different behaviors in order to influence the opinions of people in their social environment about themselves. This situation is seen in business life as well as in personal life and employees’ resort to various tactics to influence individuals’ impressions about themselves. In terms of senior management, CEOs represent their companies and are followed by their interested parties. Considering the effects of CEOs’ statements on both internal and external stakeholders, the impression management tactics in their messages can play an important role in influencing the audience’s opinions about the company. Therefore, this study aims to conduct a literature research to identify the impression management tactics in the texts of CEOs’. Twenty-nine articles examined on the subject reveal that CEOs’ personality and demographic characteristics, founder status, recognition and culture have an impact on how CEOs manage their impressions. In addition, impression management plays a role in communicating with stakeholders in times of crisis, influencing the forecasting behavior of financial analysts, and providing insight to followers about the possibility of CEOs leaving their positions. Moreover, impression management tactics may differ depending on the type of reports containing CEO messages and the company’s performance. Research also reveals similarities and differences in the messages written by CEOs and board chairs. When the studies are analyzed, it is seen that in addition to topics such as sustainability and intellectual capital in CEOs’ statements, negative expressions are also discussed within the scope of impression management
Specific features of epitope-MIPs and whole-protein MIPs as illustrated for AFP and RBD of SARS-CoV-2
Get PDFMolecularly imprinted polymer (MIP) nanofilms for alpha-fetoprotein (AFP) and the receptor binding domain (RBD) of the spike protein of SARS-CoV-2 using either a peptide (epitope-MIP) or the whole protein (protein-MIP) as the template were prepared by electropolymerization of scopoletin. Conducting atomic force microscopy revealed after template removal and electrochemical deposition of gold a larger surface density of imprinted cavities for the epitope-imprinted polymers than when using the whole protein as template. However, comparable affinities towards the respective target protein (AFP and RBD) were obtained for both types of MIPs as expressed by the KD values in the lower nanomolar range. On the other hand, while the cross reactivity of both protein-MIPs towards human serum albumin (HSA) amounts to around 50% in the saturation region, the nonspecific binding to the respective epitope-MIPs is as low as that for the non-imprinted polymer (NIP). This effect might be caused by the different sizes of the imprinted cavities. Thus, in addition to the lower costs the reduced nonspecific binding is an advantage of epitope-imprinted polymers for the recognition of proteins