Fouling is the accumulation of undesired particles on heat transfer surfaces which affects the heat transfer performance of a heat exchanger negatively. The accumulation of these particles prevents heat from being transformed through the heat exchangers by generating a fouling layer-like insulation. The main aim of the thesis is to investigate the machine learning algorithms to classify and predict the fouling status of PHE used in combi-boilers, to generate the background of the predictive maintenance, besides investigating the fouling effect on PHEs in terms of heat transfer and energy consu ...Daha fazlası
Within the scope of this thesis, PLA-based composites have been developed and coated with peptide to increase biocompatibility for temporary implant applications and PLA biocomposite materials have been produced. HA and β-TCP were used as additive materials, and PLLA and PDLA polymers were used as polymer matrix. The main purpose is to obtain the composite with the best mechanical properties and to improve the biocompatibility properties as a result of coating this final material with peptide. In the first stage, 10% HA (PLA-10 HA), 10% β-TCP (PLA-10TCP) and 5% HA + 5% β-TCP (PLA-5TCP-5HA) are ...Daha fazlası
Plasma is an ionized gas generated under an electric field that contains photons, free electrons, ions, free radicals, and reactive oxygen/nitrogen species (RONS). Cold atmospheric plasma (CAP) is generated in the cold form under a high electric field at atmospheric pressure. CAP is generated using two methods, Dielectric Barrier Discharge (DBD) and plasma jet. In the DBD method, the electrode configuration, shape, material, and substance from which the dielectric barrier is made are important. Beyond the electrode design and geometry, the barrier and electrode materials can also impact the re ...Daha fazlası
Excessive use of global energy sources causes negative environmental impacts and a reduction in the available energy resources. Therefore, energy efficiency is the main scope of engineering studies. Since household refrigeration accounts for a large portion of the energy consumption rate in buildings, several innovative techniques have been developed to improve the energy efficiency of vapor compression refrigeration systems. Suction line heat exchangers are considered one of these techniques and they are used to avoid the presence of liquid at the compressor and to prevent sweating on the suc ...Daha fazlası
The way a droplet behaves when it lands on a surface depends on the characteristics of the surface and the flow conditions of the droplet. It can deposit, rebound, splash, etc. There is delimited research on how surface roughness and chemical composition affect the deformation of droplets upon impact, in comparison to the studies done on smooth surfaces. Our model uses two-phase flow to simulate the axisymmetric motion of droplets over surfaces with heterogeneities by combining the Navier-Stokes equations for motion with the Cahn-Hilliard equation for tracking the phase-field. We integrate the ...Daha fazlası
Bu çalışmada, farklı zeminler ve geomembranlar (GM) arasındaki arayüzleri
etkileyen mühendislik parametreleri, kür sıvısı, kür süresi ve normal gerilme sınıfı
gibi çeşitli koşullar altında incelenmiştir. Ayrıca depolama sahaları gibi birden çok
geosentetiğin (GS) bir arada kullanıldığı tasarımlarda, GS’ler arasında oluşan
arayüzeylerde de potansiyel kayma yüzeyleri oluşabilir. Bu nedenle, bu çalışmada
aynı zamanda GM ve geotekstiller arasındaki arayüzeyler de araştırılmıştır. İlk
aşamada, GS’lerin ve zeminlerin mühendislik parametreleri laboratuvar deneyleri ile
belirlenmiştir. İkinci a ...Daha fazlası
With the rapid development of technology, cellular networks can no longer meet the
demands of wireless networks. Communication systems need to be updated to ensure
that every user equipment (UE) receives accurate and efficient service. Cell-free (CF)
networks offer advantages over cellular networks, such as more flexible resource
allocation, higher capacity, better coverage and lower interference. The deployment of
multiple access points (APs) and flexible allocation of resources leads to higher
network performance and efficiency. In addition, in CF networks, users can
communicate with ...Daha fazlası
In this study, the necessary data obtained from the databases (such as MSSQL, Mysql, Postgre SQL, etc.) of the softwares like ETA and NETSİS that are used for preaccountancy of the local and global companies were read, some of the data were written to the databases, and this data was used by the end user by using mobile phones or tablets carrying Android operating systems and working with Internet and cloud technology. In addition, new data sets that are collected on a cloud system from the accounting data while the company is on was studied by genetic algorithms which are one of the artificia ...Daha fazlası
This thesis presents both control of mobile robots that can move by using collective motion algorithm and simulation of the robots during the motion. The orientation of the robots was controlled remotely by one user during the collective motion. The transmission of orientation data from the remote controller to the robots was done by using XBee modules. The control algorithm of collective motion was developed by using individual-based model. Two modes are considered during the control. These modes are search and swarm mode.
The collective motion was performed by robots that are moving with re ...Daha fazlası
Photocatalytic degradation and complete mineralization of toxic organic compounds in water, soil, and air in the presence of semiconductor materials have received much attention over the last decades. Electronic structure of semiconductors is characterized by a filled valence band and an empty conduction band. When the semiconductor is irradiated with light of sufficient energy corresponding to or exceeding its band gap, an electron is promoted into the conduction band, leaving a hole in the valence band. The electrons and holes are good reductants and powerful oxidants, respectively, and they ...Daha fazlası
Today, thermoplastic polyurethane materials are widely used in many different
applications. There are many types of thermoplastic polyurethanes which offers
different mechanical and chemical properties according to application area. In
addition to the existing properties, thermoplastic polyurethane materials mixed with
various additives to obtain specific, targeted thermoplastic polyurethane materials in
order to impart different properties to the material for application.
In this study, materials of the sealing elements are approached which is one of the
most important parts of the hyd ...Daha fazlası
The goal of this thesis is to develop the applicability of an ultra-low cost, field-deployable, plastic fiber based smartphone spectrometer system to study dye adsorption from water. A custom cradle using smartphone’s built-in flash and camera was designed for visible absorbance spectroscopy without any need for external electrical components. We firstly investigated the performance of smartphone spectrometer for methylene blue (MB) absorbance in water with a detection limit of 0.5 ppm, and compared it to that of a commercial spectrometer. We elaborated on the contribution of image formats to ...Daha fazlası
6698 sayılı Kişisel Verilerin Korunması Kanunu kapsamında yükümlülüklerimiz ve çerez politikamız hakkında bilgi sahibi olmak için alttaki bağlantıyı kullanabilirsiniz.