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A hybrid forecasting approach for demand prediction in the perfume industry
No full textAccuracy in demand forecasting is a key pillar that supports effective supply chain
management and operational effectiveness as it covers various industries .However,
traditional forecasting methodologies often struggle to keep pace with the complex and
constantly evolving nature of demand re subject to the influence of multiple factors. To
meet this complex challenge, hybrid forecasting presented them on the scene, leveraging
the combined capabilities of different distinct forecasting techniques. This thesis seeks to
present an innovative hybrid forecasting framework specifically designed for demand
forecasting, with the aim of enhancing accuracy and increasing flexibility in forecasts
Near-infrared-induced high-performance antimicrobial active coating for medical textiles based on easy-to-synthesize natural catechin with full end of life circularity
No full textThe near-infrared (NIR)-induced antimicrobial textile (CTex) exhibits significant antimicrobial and antibiofilm activity over 4log reductions (more than 99.99% killing efficiency) against methicillin-resistant S. aureus (MRSA), S. aureus, E. coli, and C. albicans within seconds under 808 nm NIR-laser irradiation by rapidly reaching almost 180 degrees C. A simple yet effective preparation method for an intensely active photothermal polymer backbone from the natural compound catechin is presented. The NIR-responsive polymer backbone was synthesized using a step-growth polymerization reaction between catechin and trimesoyl chloride. Features of this polymer, reported here for the first time, were systematically optimized: reaction conditions, chemical structure, thermal properties, and photothermal capabilities. The enhanced photothermal polymer formulation was integrated into a commercially available laboratory coat textile using a simple dip-coating method. The neat and coated textile products were evaluated by chemical and morphological analyses, as well as resistance to washing, reusability, and conversion of NIR light into thermal energy. On the aspect of sustainability, CTex is amenable to straightforward, cost-effective, and industry-friendly green chemical recycling, which was also indicated. This circular end-of-life recycling was demonstrated using a dry extrusion system, without the need for catalysts or solvents, to depolymerize the textile containing polyethylene terephthalate into constituent monomer, terephthalic acid with high-yield (97.9%) outputs
Designing and simulating neural networks for maximum power point tracking and active/reactive power control in grid-connected PV systems
No full textThis thesis explores the application of Neural Network (NN) in the management of gridconnected Photo Voltaic (PV) system. This study aims to improve the performance and
reliability of PV systems using NN capabilities. The controller modelling using
MATLAB/Simulink, the first section of the thesis designs and implements a Maximum
Power Point Tracker (MPPT) control system based on NN, designed to dynamically adapt
to variable solar radiation intensity due to weather conditions. it also raises the voltage from
260 V to 350 V despite fluctuations in radiation intensity. The result obtained indicates that
the boost converter effectively raised the PV voltage and maintain it at a certain level while
working under the guidance of the NN. The final section discusses active and reactive power
control. The algorithm provides local reactive power compensation making it economically
viable. We use five different performance scenarios of the proposed control method are tried,
and the NN controller shows remarkable flexibility and quickly adapting to fluctuations in
load and radiation. The inverter voltage of 230V was equivalent to the mains voltage due to
their parallel connection. The Total Harmonic Distortion (THD) of the grid current under all
operating conditions was measured at less than 1.86%. In addition, it has been observed that
the success rate of NN is more than 99%. This thesis provides insight into the potential of
NN in renewable energy applications by using NN, contributing to the development of a
more sustainable and stable energy grid, and obtaining an integrated system that can be
integrated with the grid.Bu tez, şebekeye bağlı Foto Voltaik (PV) sistemin yönetiminde Sinir Ağının (NN)
uygulanmasını araştırmaktadır. Bu çalışma, YSA yeteneklerini kullanarak PV sistemlerinin
performansını ve güvenilirliğini artırmayı amaçlamaktadır. Tezin ilk bölümü olan
MATLAB/Simulink kullanılarak kontrolör modellemesi, hava koşullarına bağlı olarak
değişen güneş ışınımı yoğunluğuna dinamik olarak uyum sağlamak üzere tasarlanmış, NN
tabanlı bir Maksimum Güç Noktası Takipçisi (MPPT) kontrol sistemi tasarlar ve uygular.
aynı zamanda radyasyon yoğunluğundaki dalgalanmalara rağmen voltajı 260 V'tan 350 V'a
yükseltir. Elde edilen sonuç, yükseltici dönüştürücünün NN'nin rehberliğinde çalışırken PV
voltajını etkili bir şekilde yükselttiğini ve belli bir seviyede tuttuğunu göstermektedir. Son
bölümde aktif ve reaktif güç kontrolü tartışılmaktadır. Algoritma yerel reaktif güç
kompanzasyonu sağlayarak ekonomik açıdan uygun hale getirir. Önerilen kontrol
yönteminin beş farklı performans senaryosu denenmiş olup, NN kontrolörü dikkate değer
bir esneklik göstermekte ve yük ve radyasyondaki dalgalanmalara hızlı bir şekilde uyum
sağlamaktadır. Paralel bağlanmaları nedeniyle 230V evirici voltajı şebeke voltajına
eşdeğerdi. Tüm çalışma koşulları altında şebeke akımının Toplam Harmonik Bozulması
(THD) %1,86'nın altında ölçülmüştür. Ayrıca NN'nin başarı oranının %99'un üzerinde
olduğu gözlemlenmiştir. Bu tez, NN kullanarak yenilenebilir enerji uygulamalarındaki
NN'nin potansiyeli hakkında fikir vermekte, daha sürdürülebilir ve istikrarlı bir enerji
şebekesinin geliştirilmesine katkıda bulunmakta ve şebeke ile entegre olabilecek entegre bir
sistem elde edilmesine katkıda bulunmaktadır
The effectiveness of outdoor spaces designed for the playing of children in İstanbul
Get PDFCreating spaces that not only benefit but also motivate play provides opportunities for child
development and growth. Child neural networks are programmed to develop a
comprehension of concepts like space and time through their play space explorations,
behaviours, reactions, sound, and toys. This thesis investigates how the constructed
environment, informal play, and the natural environment affect the wellness of kids, as well
as the role of architects in designing publicly accessible play spaces. There is a design gap
in comprehending the complicated population of users and the design components that
impact their health. The study examines play environments, and infrastructure. It presents
four instances of community-built playing environments, utilizing the site inventory, player
observations, child photo taping and Analysing these playgrounds in light of design criteria.
The research study's findings demonstrated that children's developmental needs are directly
impacted by the limitations of fixed playground equipment. According to the research
results, children's social and physical development is supported in some way by traditional
play structures. Nevertheless, children's cognitive and emotional development is not
facilitated by this type of equipment.Sadece fayda sağlamakla kalmayıp aynı zamanda oyunu motive eden alanlar yaratmak,
çocuk gelişimi ve büyümesi için fırsatlar sağlar. Çocuk sinir ağları, oyun alanı keşifleri,
davranışları, tepkileri, sesi ve oyuncakları aracılığıyla uzay ve zaman gibi kavramların
anlaşılmasını geliştirmek üzere programlanmıştır. Bu tez, inşa edilmiş çevrenin, gayri resmi
oyunun ve doğal çevrenin çocukların refahını nasıl etkilediğini ve ayrıca mimarların halka
açık oyun alanları tasarlamadaki rolünü araştırmaktadır. Karmaşık kullanıcı nüfusunu ve
sağlıklarını etkileyen tasarım bileşenlerini anlamada bir tasarım boşluğu vardır. Çalışma,
oyun ortamlarını ve altyapıyı inceler. Site envanterini, oyuncu gözlemlerini, çocuk fotoğraf
çekimini ve bu oyun alanlarını tasarım kriterleri ışığında analiz ederek topluluk tarafından
inşa edilmiş dört oyun ortamı örneği sunar. Araştırma çalışmasının bulguları, çocukların
gelişimsel ihtiyaçlarının sabit oyun alanı ekipmanlarının sınırlamalarından doğrudan
etkilendiğini göstermiştir. Araştırma sonuçlarına göre, çocukların sosyal ve fiziksel gelişimi
geleneksel oyun yapıları tarafından bir şekilde desteklenmektedir. Bununla birlikte,
çocukların bilişsel ve duygusal gelişimi bu tür ekipmanlar tarafından
kolaylaştırılmamaktadır
Design of power control circuit for grid-connected PV system-based neural network
No full textThis research explores the application of neural networks in managing grid- photovoltaic (PV) systems. this paper aims to improve the performance and reliability of PV systems using artificial intelligence capabilities, specifically neural networks. The main emphasis of this system is to control active and reactive power and to track the maximum power point (MPPT). This study introduces an intelligent control technique for fuel cell distributed generation (DG) grid connection inverters. The algorithm allows for the management of both active and reactive power for the unit. The algorithm provides local reactive power compensation, making it economically viable. The controller modeling and performance validation are conducted using MATLAB/Simulink and Sim power system blocks, demonstrating its capacity for enhancing power factor. This makes fuel cell technology a clean, highly controllable, and economically viable option for DG systems. The system maximizes the energy extraction of PV panels and maintains them at their ideal PowerPoint across various environmental conditions. It also raises the voltage from 260 volts to 350 volts. Simulations and practical evaluations validate the proposed control system. The obtained results indicate that the total harmonic distortion (THD) of the grid current under operating conditions was less than 1.86%. This demonstrates significant improvements in the efficiency and reliability of PV systems. The neural network controller shows remarkable flexibility and the ability to quickly adapt to fluctuations in load and radiation, which contributes to developing a more sustainable and stable energy network
A potential novel technique for measurement of pulp volume on periapical radiography: A pilot study
Get PDFPulp volume can be assessed during dental treatment. Three-dimensional imaging techniques are not routinely used for this purpose because of high radiation doses. This study aimed to develop a novel method to measure pulp volume using periapical radiography. In this study, cone-beam computed tomography (CBCT) was used as a reference method. Periapical radiography and CBCTs obtained from the same patients (n = 32) were recorded. Pulp volume was determined by observing the density differences between the pulp and peripheral structures using ImageJ. A method of graph and volume calculation was developed for each tooth. The Shapiro-Wilk test and Mann-Whitney U test were used to show normality and non-normal distributions. The Bland-Altman plot was used to show the scattering of the mean versus difference values of the measurements of the two methods used to calculate the pulp volume. Normality was evaluated using the Shapiro-Wilk test. CBCT measurements are normally distributed (p = 0.307), while ImageJ is not normally distributed (p = 0.027). Therefore, the mean difference between the two groups was analyzed using the nonparametric Mann-Whitney U test. There was a statistically significant difference between the CBCT and ImageJ measurements (p = 0.01). According to Spearman's correlation analysis, the results obtained from the novel method were moderately correlated with those obtained from the reference method (r = 0.444). The results of this study indicated that a novel method-based Java software can be used to calculate pulp volume using low-dose radiation containing periapical radiography
Optimizing MIMO-OFDM communication systems: a comparative analysis of LMMSE and LZF equalizers under varying antenna configurations
No full textOrthogonal Frequency Division Multiplexing (OFDM) has emerged as a fundamental modulation technique in modern broadband wireless communication systems, effectively addressing challenges arising from dispersive channels and random fading phenomena. By employing orthogonal subcarrier frequencies, OFDM enables the simultaneous transmission of multiple in-formation symbols, thereby mitigating Inter-Symbol Interference (ISI) often encountered in scenarios characterized by multi-path propagation. In contrast to traditional Frequency Division Multiplexing (FDM) methods, OFDM eliminates the need for guard bands between adjacent frequency bands, thereby improving spectral efficiency for high-speed data transmission. This paper conducts an extensive analysis of Zero Forcing (ZF) and Minimum Mean Squared Error (MMSE) equalizers in wireless Multi-Input Multi-Output (MIMO) systems employing BPSK, QPSK, and 16-PSK modulations. Lever-aging MATLAB-based simulations, diverse configurations involving multiple transmit and receive antennas are explored, yielding insightful findings concerning output Signal-to-Noise Ratio (SNR) and Bit Error Rate (BER). Our study underscores the efficacy of OFDM-MIMO systems with equalizers in enhancing communication performance across a spectrum of wireless scenarios, offering valuable insights for both theoretical exploration and practical implementation
X, Y, Z kuşağı temsilcilerinin yeşil tüketim alışkanlıkları
Get PDFBu çalışmada, yeşil tüketimde kuşak farklılıklarının incelenmesi amaçlanmıştır. Bu
kapsamda katılımcıların yeşil tüketim değerleri ve yeşil satın alma davranışı seviyelerinin
kuşaklarına göre farklılık gösterip göstermediği incelenmiştir. Bunun yanında, çalışmada
yeşil tüketim değerlerinin yeşil satın alma davranışları üzerindeki etkilerini incelenmek de
amaçlanmıştır. İlişkisel tarama modelinde gerçekleştirilen bu çalışma, kolayda örnekleme
yöntemiyle seçilen 385 katılımcı ile yürütülmüştür. Çalışma verileri çevrimiçi olarak
hazırlanan bir anket yardımıyla toplanmıştır. Demografik sorular dışında kişilerin yeşil
ürünleri tercih edip etmeyeceğini ölçebilmek, davranışlarını anlamak ve bu davranış
stillerine şekil veren etkeneri belirlemek içinde yeşil satın alma ölçeği yer alır. ANOVA
analizleri sonucunda fonksiyonel kalite değeri, fonksiyonel fiyat değeri, epistemik değer ve
yeşil satın alma davranışının Z kuşağında anlamlı olarak daha yüksek seviyede olduğu
belirlenmiştir. Bunun yanında, koşullu/duygusal değerin ise X kuşağında anlamlı olarak
daha yüksek seviyede olduğu belirlenmiştir. Diğer taraftan sosyal değerin kuşaklara göre
anlamlı farklılık göstermediği belirlenmiştir. Regresyon analizi sonucunda ise yeşil satın
alma davranışı üzerinde fonksiyonel fiyat değeri ve koşullu/duygusal değerin olumlu yönde
ve anlamlı etkilerinin olduğu, fonksiyonel kalite değeri, sosyal değer ve epistemik değerin
ise anlamlı etkilerinin olmadığı tespit edilmiştir. Çalışma sonuçlarımız göstermiştirki X,Y,Z
kuşağı temsilcilerinin yeşil ürünlere verdiği değer anlamlı derecede farklıdır ve bu farklılık
kişilerin demografik bulguları ile doğrudan ilişkilidir. Kaliteye, faydaya ve duygulara verilen değerin ölçülmesi için yapılan anket sonuçları günümüz dünyasında etkin rol oynamaya
henüz başlamış olan Z kuşağı temsilcilerinin özellikle X kuşağı temsilcilerine göre daha
sorgulayan daha “kaliteli” bir çevrede yaşamak isteyen bir kuşak olduğu ortaya
çıkarmaktadır.
Sonuçlar ışığında beklentimiz odur ki arzı doğuran talep daha iyisini istediği sürece bütün
paydaşlar bu talebin gereklerini yerine getirmek için daha hızlı hareket edecekler ve çevre
sorunları, daha ciddi alanlarda bir insanlık problemi olarak ele alınabilecektir ve bütün dünya
vatandaşları bu yüksek bilince kavuşacaktır.In this study, it is aimed to examine generational differences in green consumption. In this
context, it was examined whether the green consumption values and green purchasing
behavior levels of the participants differ according to their generations. In addition, it is
aimed to examine the effects of green consumption values on green purchasing behaviors in
the study. This study, which was carried out in relational screening model, was carried out
with 385 participants selected by convenience sampling method. The study data were
collected with the help of an online questionnaire. The green purchasing scale is used to
measure whether people prefer green products apart from demographic questions, to
understand their behavior and to determine the factors that shape these behavior styles. As a
result of ANOVA analysis, it was determined that functional quality value, functional price
value, epistemic value and green purchasing behavior were significantly higher in
Generation Z. In addition, it was determined that the conditional/emotional value was
significantly higher in the X generation. On the other hand, it was determined that social
value did not differ significantly according to generations. As a result of the regression
analysis, it was determined that functional price value and conditional/emotional value had
positive and significant effects on green purchasing behavior, while functional quality value,
social value and epistemic value did not have significant effects. Our study results showed
that the value given to green products by the representatives of the X, Y, Z generation is significantly different and this difference is directly related to the demographic findings of
the people. The results of the survey conducted to measure the value given to quality, benefit
and emotions reveal that the representatives of the Z generation, who have just begun to play
an active role in today's world, are a generation that wants to live in a more "quality"
environment, which is more questioning than the representatives of the X generation.
In the light of the results, our expectation is that as long as the demand that creates the supply
wants better, all stakeholders will act faster to fulfill the requirements of this demand, and
environmental problems will be considered as a humanitarian problem in more serious areas,
and all citizens of the world will attain this higher consciousness
Multimodal battle royale optimizasyon algoritmasi
No full textFarklı alanlarda birçok karmaşık problemi çözmek için çeşitli metaheuristik optimizasyon
yaklaşımları geliştirilmiştir. Stokastik metasezgisel optimizasyon algoritmaları üç ana
kategoriden oluşmaktadır: Evrimsel algoritmalar, sürü tabanlı ve fiziksel denklem tabanlı
algoritmalardır. Battle Royal Optimizasyon algoritması oyun tabanlı algoritma olarak
literatüre dördüncü bir kategori olarak eklenmiştir.
Önerilen yöntem, “Battle Royale" olarak bilinen bir dijital oyun türünden esinlenmiştir.
"BRO, her bireyin en güvenli (en iyi) yere doğru ilerlemek ve nihayetinde hayatta kalmak
isteyen bir asker/oyuncu tarafından temsil edildiği popülasyon tabanlı bir algoritmadır.
Tez kapsamında; Battle Royale Optimizasyon algoritmasını hiçbir parametreye ihtiyaç
duymadan multimodal problemleri çözmesi amaçlanmaktadır. Multımodal Battle Royale
Algoritmasındaki uyarlamalar ile, tek bir çözüme yakınsama olmadan arama alanının birden
fazla optimum noktayı keşfetmesi amaçlanmaktadır.Various metaheuristic optimization appoaches have been developed to solve many complex
problem in diffirent fields. Stochactic metaheuristic optimization algorithms consist of three
main categories: Evolutionary Algorithms, Swarm Intelligence, and physics-based
algorithms. The Battle Royale Optimizastıon algorithm has been added to the literatüre as a
fourth category as a game-based algorithm.
The proposed method is inspired by a digital game known as “Battle Royale”. The Battle
Royale Optimization (BRO) is a populatıon-based algorithm, where each individual is
represented by a soldier/player aiming to move towards the safest (best) position and
ultimately survive.
In this thesis, the Battle Royale Optimization algorithm aims to solve multımodal problems
without needing any parameters. With adaptations in the Multımodal Battle Royale
Algorithm, it aims to explore multiple optimal points in the search space without converging
to a single solution
MANDIBULAR METASTASIS OF RENAL CELL CARCINOMA: AN UNCOMMON CASE
No full textAmong the masses seen in the oral cavity, distant metastases constitute 1% of all oral cavity neoplasms. Within this 1%, renal cell carcinoma is the third most common cancer that metastasises to the oral cavity after lung cancer and breast cancer, respectively. Although thyroid, salivary glands, skull base, sinuses, pharynx, tonsils, tongue, lips and skin metastases have been reported in the literature in order of incidence, very few renal cell carcinoma mandibular metastases have been reported in the literature in the last 25 years. A patient referred to our clinic by a dentist presented with swelling on the left side of the face and a 2x3 cm radiolucent lesion in the left mandibular corpus on orthopantomogram. The patient had previously been diagnosed with renal cell carcinoma and had received chemotherapy followed by targeted therapy for one year. After advanced radiological examinations, the pathology of the biopsy taken under general anaesthesia was reported as renal cell carcinoma. By sharing this experience with clinicians, the aim is to raise awareness that metastasis of an existing malignancy should be considered in the preliminary diagnosis of patients with known malignancies other than in the head and neck region who present with swelling in areas such as the mandible where distant metastasis is uncommon