Maden Mühendisliği Bölümü Koleksiyonu

Bu koleksiyon için kalıcı URI

https://hdl.handle.net/11468/10522

Listeleniyor 1 - 16 / 16

An investigation on the efficiency of water-jet technology for graffiti cleaning
(Elsevier Masson SAS, 2016) Careddu, Nicola; Akkoyun, Özgür
The scope of this study is to investigate the possible usage of water-jet technology for graffiti cleaning and to find out the best operational conditions of water-jet machine as cleaner. For this goal, Carrara marble was selected as a test stone. Three samples were prepared and 12 different areas were determined on them. Then, different operational conditions of water-jet were applied into these twelve pre-painted marble surfaces. These different operational conditions involve different travel speed, water pressure or inter-distance between passes of the machine to figure out the best combination. After that, image analysis methods were used in order to evaluate the conditions and find out the best one. In addition, roughness features of the marble samples were measured, because water-jet application can cause excavation, which may affect on the stone surface. Finally, it is concluded that water-jet machine can be used for graffiti cleaning with specific operational conditions, which are selected by using both image analysis and roughness test results. As a conclusion, it can be said that if the stone is painted heavily, then travel speed of the machine must be reduced. Oppositely, if the stone is slightly painted, the best solution is to increase both the inter-distance between passes and the travel speed of the jet. Economic considerations of water-jet application are also carried out.
Multiple cut-off grade optimization by genetic algorithms and comparison with grid search method and dynamic programming
(South African Institute of Mining and Metallurgy, 2016) Çetin, Erhan; Dowd, P. A.
Optimization of cut-off grades is a fundamental issue for mineral deposits. Determination of optimum cut-off grades, instead of application of a static cut-off grade for the life of a mine, maximizes the net present value. The authors describe the general problem of cut-off grade optimization for multi-mineral deposits and outline the use of genetic algorithms, the grid search method, and dynamic programming for optimal cut-off grade schedules for deposits with up to three constituent minerals. The methods are compared by assessing the results of the implications involved in using them.
The optimization of cut-off grades by means of memetic algorithms
(Polska Akademia Nauk, 2022) Çetin, Erhan; Dalgıç, Abdurrahman
Cut-off grades optimization is a fundamental issue for mineral deposits. A cut-off grade is any grade that is used to separate two courses of action; to mine or not to mine, to process or to dump. In order to achieve the maximum discounted cash flow, generally a decreasing order of cut-off grades schedule takes place. Variable mining costs are applied to the extracted material, not to all of the depletion rate as some of the depletion can be left in-situ. Because of access constraints, some of the blocks that have an average grade less than the determined cut-off grade are left in-situ, some of them are excavated and dumped as waste material. The probability density function of an exponential distribution is used to find the portion of the material below the cut-off used that is left in situ. The parts of a mineral deposit that are excavated but will be dumped as waste material and tailings of ore incur some additional cost of rehabilitation. The method of memetic algorithms is a very robust optimization tool. It is a step further from the genetic algorithms. The crossover, mutation and natural selection behavior of the method ensures it escape from a local optimum point, and a further local search improves the optimum further. This paper describes the general problem of cut-off grades optimization, outlines the use of memetic algorithms in cut-off grades optimization and further exten-sion of the method including partial depletion rates and variable rehabilitation cost. This paper is the first application of memetic algorithms to cut-off grades optimization in this context.
Refrakter olmayan sülfürlü altın-gümüş cevherinin flotasyon davranışının incelenmesi
(Niğde Ömer Halisdemir Üniversitesi, 2020) Aydın, Ş. Beste; Aydın, Deniz; Gül, Alim
Bu çalışma kapsamında refrakter olmayan sülfürlü altın-gümüş cevherinin zenginleştirilmesinde çevreye daha dost proseslerden olan flotasyon yönteminin uygulanabilirliği araştırılmıştır. Çanakkale-Serçeler bölgesinden temin edilen 18,85 ppm Au ve 120 ppm Ag içeren numune üzerinde gerçekleştirilen flotasyon çalışmalarına göre, -74 µm tane boyutunda, kaba devrede 1000+1000 g/t Aerophine 3418 A+Aero 208 kullanımı ve 2 kademeli temizleme devresi ile konsantrede %75,8 verim ile 625 ppm Au, %86,5 verim ile 4833 ppm Ag elde edilmiştir. Kaba devrede 1500+1500 g/t Aerophine 3418 A+Aero 208 kullanımı ve 3 kademeli temizleme devresi ile ise konsantrede %69,6 verim ile 1026,5 ppm Au, %80,6 verim ile 8058,1 ppm Ag elde edilmiştir. Bu sonuçlara göre, refrakter olmayan sülfürlü altın-gümüş cevherinden flotasyon yöntemi ile doğrudan izabeye gönderilebilecek nitelikte bir konsantre elde edilebileceği belirlenmiştir. Flotasyon kinetiği ile ilgili çalışmalarda ikinci derece kinetik modelinin bu cevher için uygulanabilir olduğu ve ikinci dereceden flotasyon kinetik sabitleri göz önüne alındığında, gümüşün altına göre 2,5 kat daha fazla flotasyon hızına sahip olduğu sonucuna varılmıştır
Avnik (Bingöl) açık ocak demir işletmesinde şev duraylılığının farklı yöntemlerle incelenmesi
(Hacettepe Üniversitesi Yerbilimleri Uygulama ve Araştırma Merkezi, 2023) Varol, Ogün Ozan; Ayhan, Mustafa; Akın, Mutluhan
Ülkemizin en önemli demir yataklarının işletildiği Avnik Demir İşletmesi, Bingöl ilinin güney doğusunda ve yaklaşık 40 km uzaklıkta yer almaktadır. Bu çalışmada kazı derinliğinin günümüzde 333 m’ye ulaştığı Avnik Demir İşletmesi’ndeki şevlerin duraylılığı incelenmiştir. Yapılan arazi çalışmaları kapsamında açık ocak işletmesinin şevlerini oluşturan birimlerde süreksizlik hat etütler yapılmıştır. Süreksizlik hat etütleri neticesinde süreksizliklerin özellikleri belirlenmiştir. Yapılan arazi çalışmaları sonucunda inceleme alanındaki metamorfik kayaçların ileri derecede çatlaklı ve kırıklı bir yapı kazandığı ortaya konmuştur. Öte yandan açık ocak işletmesinde daha önceki dönemlerde iki farklı noktada birleşik kayma yüzeyli duraysızlıklar gelişmiştir. Açık ocak işletmesindeki kritik işletme şevleri boyunca kesitler alınmış ve bu kesitler üzerinde statik - kuru ve dinamik – kuru koşullar için limit denge ve sonlu elemanlar yöntemleri kullanılarak şev duraylılık analizleri gerçekleştirilmiştir. Hem limit denge hem de sonlu elemanlar yöntemiyle yapılan analiz sonuçlarına göre açık ocak işletmesinin kuzeyinde yer alan şevlerin dinamik koşullarda güvenlik katsayılarının azaldığı ve kritik limit denge durumuna oldukça yaklaştığı tespit edilmiştir.
MediNet: transfer learning approach with MediNet medical visual database
(Springer, 2023) Reis, Hatice Çatal; Türk, Veysel; Khoshelham, Kourosh; Kaya, Serhat
The rapid development of machine learning has increased interest in the use of deep learning methods in medical research. Deep learning in the medical field is used in disease detection and classification problems in the clinical decision-making process. Large amounts of labeled datasets are often required to train deep neural networks; however, in the medical field, the lack of a sufficient number of images in datasets and the difficulties encountered during data collection are among the main problems. In this study, we propose MediNet, a new 10-class visual dataset consisting of Rontgen (X-ray), Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Ultrasound, and Histopathological images such as calcaneal normal, calcaneal tumor, colon benign colon adenocarcinoma, brain normal, brain tumor, breast benign, breast malignant, chest normal, chest pneumonia. AlexNet, VGG19-BN, Inception V3, DenseNet 121, ResNet 101, EfficientNet B0, Nested-LSTM + CNN, and proposed RdiNet deep learning algorithms are used in the transfer learning for pre-training and classification application. Transfer learning aims to apply previously learned knowledge in a new task. Seven algorithms were trained with the MediNet dataset, and the models obtained from these algorithms, namely feature vectors, were recorded. Pre-training models were used for classification studies on chest X-ray images, diabetic retinopathy, and Covid-19 datasets with the transfer learning technique. In performance measurement, an accuracy of 94.84% was obtained in the traditional classification study for the InceptionV3 model in the classification study performed on the Chest X-Ray Images dataset, and the accuracy was increased 98.71% after the transfer learning technique was applied. In the Covid-19 dataset, the classification success of the DenseNet121 model before pre-trained was 88%, while the performance after the transfer application with MediNet was 92%. In the Diabetic retinopathy dataset, the classification success of the Nested-LSTM + CNN model before pre-trained was 79.35%, while the classification success was 81.52% after the transfer application with MediNet. The comparison of results obtained from experimental studies observed that the proposed method produced more successful results.
Farklı ISG-RİSK değerlendirme yöntemlerinin bir yeraltı maden işletmesinde karşılaştırmalı uygulanması ve yöntem önerisi
(TMMOB Maden Mühendisleri Odası, 2021) Akkoyun, Özgür; Ekinci, Ğurbet
Bu çalışmada bir yeraltı maden işletmesinde iş sağlığı güvenliği kapsamında risk değerlendirme çalışması yapılmıştır. En çok kullanılan risk değerlendirme yöntemlerinden olan 5x5 L matris ve Fine-Kinney yöntemleri ile çok bilinmeyen HRNS risk değerlendirme yöntemi bir yeraltı maden işletmesine uygulanarak karşılaştırılmışlardır. Buna göre 5x5 L matris yönteminin esnek olduğu, düşük seviyeli riskleri görmeye yatkın olduğu, Fine-Kinney yönteminin daha az esnek olduğu görülmüştür. HRNS yönteminin ise riskleri görmek konusunda daha iyi olduğu, özellikle tehlike seviyesi yüksek riskleri görme konusunda diğerlerine göre daha iyi olduğu sonuçlarına varılmış ve maden işletmeleri gibi çok riskli işyerleri için HRNS yöntemi önerilmiştir.
Kaya kütle makaslama dayanımının geri analiz yöntemi ile belirlenmesi: Bir vaka analiz
(TMMOB Maden Mühendisleri Odası, 2021) Varol, Ogün Ozan; Ayhan, Mustafa; Akın, Mutluhan
Bu çalışma kapsamında, Avnik (Bingöl) demir açık ocak işletmesinde meydana gelen şev duraysızlıkları incelenmiştir. Duraysızlıklar; ileri derecede kırıklı, çatlaklı, fillit ve şist birimlerinde meydana gelmiştir. Limit denge analiz yöntemi ile geri analizler yapılmış ve duraysız şevlerin makaslama dayanım parametreleri belirlenmiştir. Limit denge yöntemi ile makaslama dayanım parametreleri belirlenirken Hoek – Brown yenilme ölçütü kullanılmıştır. Geri analizler neticesine elde edilen GSI değerleri (35 - 32) ile arazi çalışmalarından elde edilen GSI değerleri (41 – 35) birbirleri ile uyumludur. Geri analizler neticesinde fillit ve şist birimleri için Hoek – Brown parametreleri sırası ile mb: 0,147 ve 0,173, s: 3,305x10-5 ve 8,566x10-5, a: 0,516 ve 0,511 olarak hesaplanmıştır.
Farklı yaklaşımlarla madenler ve değerli taşlar
(Orient Yayınları, 2022) Kavak, Orhan; Haspolat, Yusuf Kenan
Jeoloji sözcük olarak Türkçede Yerbilimi anlamına gelmektedir. Latince “Geologia; Geo-Yer, Logia-Bilim” sözcüklerinden türetilmiş bir kavramdır. Jeoloji geniş anlamda Yerküreyi, dar anlamda Litosferi, daha da dar anlamda Litosferin Üst seviyesi olan Yerkabuğunun oluşumunu, bileşimini, yapısını, hareketini, değişiklikleri, değişiklikleri yaratan olayları ve tarihsel evrim bakımından araştırıp inceleyen bir bilim dalıdır. Bilimsel açıdan daha çok bir Fen ya da Doğa Bilimi niteliği taşıyan Jeoloji; uygulamalar dikkate alındığında ağırlıklı olarak Mühendislik Bilimleri grubundan sayılmaktadır. Jeolojiyi daha geniş açıklamalı olarak aşağıdaki gibi tanımlayabiliriz (1). Jeoloji: • İnsanoğlunun üzerinde yaşadığı Dünya’nın doğası hakkında merakını uyandıran pek çok somut sorunun bilimsel ve pratik yanıtlarını veren; • Yerkabuğunda insanlara büyük yararlar sağlayan her türlü Maden, Petrol, Doğal Gaz, Kömür, Yer Altı Suyu, Endüstriyel Hammaddeler gibi Yer Altı Zenginliklerinin aranıp bulunması, bunların işletile bilirlik özelliklerinin belirlenmesi hizmetlerini yürüten; • Yerleşim yeri ile Bina, Yol, Tünel, Köprü, Baraj, Havaalanı gibi her türlü yapı için uygun Yer ve Zemin seçimi, Zeminlerin Jeolojik özelliklerinin belirlenmesi, Mineral kökenli yapı malzemesinin aranıp bulunması çalışmalarını yürüten; • Başka bilim ve meslek dalları yanında insanların Deprem, Yanardağ Patlaması, Heyelan, Sel gibi Doğal Afetlerle savaşımında çok önemli katkılar sağlayan bir bilim ve mühendislik dalıdır
Geochemistry and origin of bituminous samples of Kuriki Höyük (SE Turkey) from 4000 BCE to 200 CE: Comparison with Kavuşan Höyük, Hakemi Use and Salat Tepe
(Elsevier, 2022) Connan, Jacques; Genç, Elif; Kavak, Orhan; Engel, Michael H.; Zumberge, Alex
Twelve samples of organic mixtures collected from floors and potsherds in different areas of Kuriki Hoyuk (SE Turkey) were analyzed by geochemical techniques to identify bitumens and try to locate their sources. Oil seeps from the region (Gercus, Badzivan, Zengen, Kerbent, Kayatepe, Eruh) and some other samples characterized later as asphaltites (Kumcati, Anittepe, Silip), were compared to the archaeological mixtures. To trace the source of bitumen, stable carbon isotope values of chromatographic fractions and mass fragmentograms of steranes and terpanes were acquired on both archaeological mixtures and oil seeps used as references. Bitumen was recognized in all samples and the Kerbent oil seep is the most likely source of bitumen at Kuriki Hoyuk. This source was used from 4000 BCE to 200 CE. In contrast, Eruh appears to be the likely source for the other archaeological sites of the neighbourhood namely: Kavusan Hoyuk, Salat Tepe and Hakemi Use. The mineral composition of archaeological samples shows that the mixtures used at Kuriki Hoyuk are similar to those observed elsewhere in many archaeological bitumens from other localities.
Petrographical and chemical properties of mus coals
(Institute of Physics Publishing, 2019) Kavak, Orhan
One of the most important natural energy resources of our country stands to be as coal; our reserve with the newly discovered bed exceeds more than 14 billion tons. Although the higher quality coals are located at the western and inner part of Anatolia, there are some coal beds in the eastern Anatolia as well. The coals near Muş city are one of them. The coals are Tertiary (Pliocene) aged coals. Petrographical and chemical properties, as moisture, volatile matter, fixed carbon, ash content of the coals were determined in this study. The coals are of many thin layers and of a total thickness varying between 0.9-3.6 meters. The original coals contain of an average lower calorific value about 1200 Kcal/kg. Their ash content changes between 17-30 %, moisture with 30% average. The coals exhibit higher moisture content which is thought to be derived from high ground water level and of surfical water inputs. The dominant maceral of the coals is huminite, changing between 28 to 61 % amount. Gelinite is the most common huminites. Liptinite content changes between 2-5% and inertinite, between 2-11 %. The huminite reflectance (Ro) were measured as changing between 0.10 - 0.29 % (standard deviation as 0.01 - 0.02%) and corresponds to lignite rank. The low reflectance values are probably resulted from their shallow burials and their being remote to tectonic activities in the region. The coals comprise of 3-6% pyrite and 14-62 clay and other inorganic materials. Muş coals were classified as poor quality lignite, based on organic petrography, coal quality data and their low maturity index. Detail coal petrographical analysis seems to indicate depositional environment of the coals to be as limnic swamps. Total reserve of the coals is about 6.2 million metric tons.
Environmental effects of petroleum leaks around Diyarbakir City (SE Anatolia of Turkey) and its environment
(Institute of Physics Publishing, 2019) Aba, Tahsin; Kavak, Orhan
Crude oil; Gasoline; Global warming; Groundwater resources; Oil fields; Oil spills; Petroleum prospecting; Petroleum transportation; River pollution; Sulfuric acid; Surface waters
Evaluation of oil fields in and around Diyarbakir (SE anatolia of Turkey) in terms of production
(Institute of Physics Publishing, 2019) Bulbul, Rıfat; Kavak, Orhan
This study aims to give information about the oil production of 42 Oil Fields and the wells of each field in Diyarbakir and the surrounding area where is geologically located at the boundary of Anatolian plate and Middle Eastern oil region in the Southeastern Anatolia of Turkey. The structure of oil reservoirs at this region, the interaction of oil and water at the reservoir, capping mechanism of reservoir oil and water are the given topics about the reservoir. Average drilling depth of oil wells at the surrounding area, chemical structure and physical properties of production formations, calculation of production rate, pump types and selecting the suitable type of pump for several production rates, advantages and disadvantages of the pump types are also the other given information about the region. Moreover, regional evaluation of the oil and water ratios, API gravity of produced oil, salinity and pH values of produced water are mentioned by using the analysis of samples taken from the wells in different regions of Diyarbakir province. The other purpose of the study is to inform about stocking of produced oil and water by using surface systems, seperation systems of oil from the water, injecting of seperated water to water injection wells, analysing the downhole and surface equipment failures for production wells and enviromental effects of oil production. Giving information about the economical aspect of the oil production for Turkey and Diyarbakir region is also one of the other goal. Solutions are offered for the encountered problems during the production, separation, transportation, and the refinery processes of the reserves in Diyarbakir city of Turkey, that imports most of its petroleum and natural gas use despite being very close to relatively large reserves.
Modelling of the hourly horizontal solar diffuse radiation in Sanliurfa, Turkey
(Serbian Society of Heat Transfer Engineers, 2020) Beyazit, Nesrin İlgin; Ünal, Fatih; Bulut, Hüsamettin
Horizontal diffuse solar radiation has been calculated over various models by using the total radiation data obtained from the horizontal surface due to reasons such as lack of adequate measurements and expensive measuring instruments. In this study, the measurements were calculated using the obtained data between the years 2009 and 2016 from solar radiation measurement system with solar tracking system, which belongs to the Department of Mechanical Engineering, Sanliurfa Harran University, Turkey. Three horizontal solar diffuse radiation models have been proposed by using the relationship between the diffuse radiation ratio and the clarity index obtained by eight years' data. Horizontal solar diffuse radiation values were calculated and compared with the measurement data for Sanliurfa by using 15 models of diffuse radiation given in the literature and the results obtained from the models. The statistical errors of the proposed models and 15 different diffusive radiation models were calculated. As diffuse radiation varies with time, it is determined that modelling of Model 1 and Model 2 obtained from Sanliurfa data gives better results in terms of clarity index constraints. Furthermore, although the desired success cannot be achieved with Model 2 in terms of tstat, it has been determined that the relevant model provides better results than many models when compared to statistical errors. With the improvements to be made on Model 2, a local estimation model is thought to give better results.
The impact of cyclic loads on physicomechanical properties of the massive and vesicular basalts
(IOP Publishing Ltd, 2020) Dursun, Felat; Topal, Tamer
Stone monuments are the most visible and essential structures of our cultural heritage; however, many of the historical structures around the world are now suffering from stone deterioration. Diyarbakır City Walls, which were acknowledged the status of World Heritage Site by UNESCO, are among the most extensive surviving structures from ancient times. The City Walls have also some deterioration related problems. Basalts having such different textural properties as massive and vesicular were employed as the principal material in the construction of the Diyarbakır City Walls. Weathering is strongly related to the climatic and environmental conditions of the site. In order to evaluate the physical deterioration, environmental conditions were artificially simulated in accelerated weathering tests such as wetting-drying, freezing-thawing, and salt crystallization. For this purpose, 180 massive and vesicular basalt samples were prepared. The effects of these tests were evaluated by visual examination, weight loss, effective porosity, dry and saturated unit weights, water absorptions under atmospheric and vacuum pressure, sonic velocity and uniaxial compressive strength. It is found that the salt crystallization is the most effective accelerated weathering test deteriorating the basalt samples most aggressively. © 2020 Institute of Physics Publishing. All rights reserved.
A Preliminary study on material properties of the Zerzevan Castle, Turkey
(IOP Publishing Ltd, 2020) Dursun, Felat; Coşkun, Aytaç
Abstract. Zerzevan is a recently discovered castle, situated on a rocky hill in the province of Diyarbakır, southeastern Turkey. Like many other Medieval defensive artifacts, Zerzevan Castle has also erected to protect the site against the incursions of enemies and to dominate the land. Zerzevan Castle, as a former military base of the Roman Empire, consists of such remains as churches, tombs observation towers, cisterns, arsenal, canals and city walls. The archaeological excavations conducted in the site revealed the existence of various underground structures, among them a temple of Mithraism, a mystery religion. The temple is considered as the first and unique Mithraeum located on the eastern border of the Roman Empire. The castle has been constructed by employing natural stones. Similar to that of the stone artifacts around the world, the Zerzevan Castle has also suffered from stone deterioration and stability problems. The present study aims to characterize stone used in the Zerzevan Castle as a building material. The study also aims to characterize the provenance of the stone material utilized in the monuments of that archaeological site. For this purpose, samples were collected from the building façade and stone quarry located on the site. The samples then used to determine their petrographic, chemical and some of the physico-mechanical properties. The preliminary results demonstrate that the stone employed in the construction of the Castle is calcitic dolomite. Moreover, the great similarities in chemical compositions of the samples collected from the building and the quarry indicate that the stone material employed in the construction was most probably extracted from the nearby quarries.

Güncel Gönderiler