Orhan Dengiz - Profile on Academia.edu (original) (raw)

Papers by Orhan Dengiz

Http Dx Doi Org 10 1080 00207540500534454, Feb 22, 2007

Advanced ceramics are commonly manufactured by sintering high-purity powders. The design of ceram... more Advanced ceramics are commonly manufactured by sintering high-purity powders. The design of ceramic elements is governed by its fracture strength, which is greatly influenced by microstructural flaws. Three ceramic powder preparation methods for ceramics manufacturing are considered in this paper-uniaxial pressing followed by isostatic pressing, flocculated slip casting, and dispersed slip casting. Their effects on the growth and characteristics of microstructure flaws and damage on the ceramic surface are investigated using a two-stage data-mining approach. In the first stage, digital microstructural images are mined to characterize the flaws and surface damage. In the second stage, an extreme value probability distribution is fitted using the information from stage 1. The extreme value distribution estimates large flaws which are highly correlated with subsequent fractures. Results of the two-stage data mining show that ceramic production method significantly affects flaw characteristics that, in turn, determine the ceramics' fracture strength.

Uzaktan Algılama ve Coğrafi Bilgi Sistem Teknikleri Kullanılarak Arazi Örtüsü / Arazi Kullanımı Zamansal DeğiĢimin Belirlenmesi: Samsun Merkez Ġlçesi Örneği (1984-2011)

Turkiye Tarımsal Arastırmalar Dergisi, Apr 9, 2014

Http Dx Doi Org 10 1080 01490451 2011 653089, 2012

Anadolu Journal of Agricultural Sciences, 2006

Geliş Tarihi: 15.09.2005 ÖZET: Bu çalışmanın amacı 33.233 dekarlık yüz ölçümüne sahip Atatürk Orm... more Geliş Tarihi: 15.09.2005 ÖZET: Bu çalışmanın amacı 33.233 dekarlık yüz ölçümüne sahip Atatürk Orman Çiftliği arazilerinin tarımsal yönden kullanım durumlarının belirlenmesidir. Bu amaçla 1:20.000 ölçekli temel toprak haritasından yararlanılarak arazi karakteristikleri ve kaliteleri ile haritalama üniteleri tanımlanmıştır. Daha sonra değerlendirmeye alınacak arazi kullanım türleri ve onların arazi istekleri belirlenmiştir. Arazi kullanım türlerinin arazi istekleri ile arazi haritalama birimlerinin arazi karakteristik ve nitelikleri karşılaştırılmıştır. Arazi haritalama birimlerinin arazi kullanım türleri ile karşılaştırılmasıyla elde edilen sonuçlar ekonomik, sosyal ve ekolojik verilerle birleştirilerek her bir arazi haritalama birimi için uygun olan arazi kullanım türleri ve uygunluk sınıfları belirlenmiştir. Son olarak ta arazi uygunluk haritası hazırlanmıştır. Tarımsal kullanıma uygunluk haritası göstermiştir ki, çalışma alanının sadece % 8.2 tarım dışı araziler oluştururken, % 54.4' ü tarımsal kullanım için oldukça iyi arazilerden oluşmaktadır. Anahtar Kelimeler: Arazi değerlendirmesi, arazi kullanım türü, arazi karakteristikleri ve kaliteleri, arazi uygunluk sınıflaması ABSTRACT: The land assessment of the soils of the Atatürk Orman Çiftliği covering 33.233 da was determined according to the agricultural uses. The land mapping units were primarily described and land characteristics and qualities were determined from 1:20.000 scaled soil maps of the area. Land use types to be considered were described and their land requirements were determined. The land requirement of the land use types were compared with the land characteristics and land qualities of land mapping units. The results of the matching process combined with those of assessment, environmental impact, economic and social analysis, produced a classification, showed the suitability of each land mapping unit for each relevant land use type. The outcoms of the suitability map for agricultural uses revealed that only 8.2 % of the study area soils was not suitable for agricultural uses 54.4 % of the study area soils was found as highly suitable for agricultural uses.

Farklı Fluviyal Depozitler Üzerinde Oluşmuş Toprakların Dağılım Alanlarının Belirlenmesi ve Sınıflaması

Türkiye Tarımsal Araştırmalar Dergisi, 2014

Toprak ile Anamateryal Arasındaki İlişkilerin Uzaktan Algılama ve Coğrafi Bilgi Sistem Teknikleri Kullanılarak Belirlenmesi

Selcuk Tarım Ve Gıda Bilimleri Dergisi a, Feb 5, 2010

Alluvial land, formed on accumulated sediment depositions by time, show large variety in their pr... more Alluvial land, formed on accumulated sediment depositions by time, show large variety in their properties at short distances. Therefore, different soils can be form on these lands. The objective of this research was to determine and classify different soils formed on alluvial land used for rice cultivation in Corum-Osmancik. Total study area is approximately 1663 ha. Average annual temperature and precipitation are 13.2 o C and 380 mm, respectively. After examination of topographic, land use, geologic and geomorphologic maps and land observation, 12 profile places were excavated in study area. Detailed land observations were done with grid method and auger examinations. The soil samples were taken from each profile and their analyses were done in the laboratory. By assessing the results of analyses and field studies, 9 different soil series were determined and described. Two of them were classified as Entisol due to their young age and four are as Inceptisol and three are as Mollisol. Whereas Taslikbasi series has the largest area (18.9 %), Dagmatoglu series has the smallest area in the study area (4.0 %). Also, suitability of soil series was investigated for the rice production and soil properties limited rice production were determined in this study.

Madendere Havzasında Fizyoğrafik Faktörlerin ve Bazı Fiziko-Kimyasal Toprak Özelliklerinin Belirlenmesi ve Haritalanması

Türkiye Tarımsal Araştırmalar Dergisi, 2015

A Genetic Algorithm for Fuzzy Optimization of the Multi-Objective Redundancy Allocation Problem

The redundancy allocation problem (RAP) is defined as the selection of components and redundancy ... more The redundancy allocation problem (RAP) is defined as the selection of components and redundancy levels to meet reliability and weight constraints collectively at minimum cost, or to maximize reliability given cost and weight constraints or to maximize reliability and minimize cost and weight simultaneously. The RAP is a NP-hard problem and different methods, mostly heuristics, are available to solve it

The main objective of this study was to determine some chemical, physical properties and extracel... more The main objective of this study was to determine some chemical, physical properties and extracellular enzymatic activities of soil modified after forestland transformation into cropland and pasture in Çankırı-Uludere watershed. In this study, the changes in the properties of four different pedons classified as Lithic Leptosol (Lithic Xerorthent, LPq), Dystric Cambisol (Typic Dystroxerept, CMd) and Haplic Cambisol (Typic Haploxerept, CMha) located on three adjacent land use types which are native forest, pasture and cultivated fields include some extracellular enzymes, organic matter, pH, EC, CaCO 3 , bulk density, total porosity, hydraulic conductivity and aggregate stability. The effects of agricultural practices on soil properties taken from each four adjacent land use types were most clearly detected in the past 50 years with the land use change. Land use change and subsequent tillage practices resulted in significant decreases in organic matter, total porosity, total nitrogen a...

Non-deterministic decoding with memory to enhance precision in binary-coded genetic algorithms

Proceedings of the 2004 Congress on Evolutionary Computation (IEEE Cat. No.04TH8753), 2004

A non-deterministic decoding algorithm for binary coded genetic algorithms is presented. The prop... more A non-deterministic decoding algorithm for binary coded genetic algorithms is presented. The proposed algorithm enhances the precision of the GA solutions by introducing a Gaussian perturbation to the decoding function. This non-deterministic decoding enables individuals to represent any point in the continuum instead of finite discrete points. As the generations evolve, information gathered from the most fit members is continuously

Application of a multicriteria decision-making approach for rice land suitability analysis in Turkey

TURKISH JOURNAL OF AGRICULTURE AND FORESTRY, 2014

Journal of environmental biology / Academy of Environmental Biology, India, 2009

The objective of this research was to assess vulnerable soil erosion risk with qualitative approa... more The objective of this research was to assess vulnerable soil erosion risk with qualitative approach using GIS in Ankara-Guvenc Basin. The study area is located about 44 km north of Ankara and covers 17.5 km2. The selected theme layers of this model include topographic factor, soil factors (depth, texture, impermeable horizon) and land use. Slope layer and land use-land cover data were prepared by using DEM and Landsat-TM satellite image. According to land use classification, the most common land use type and land cover are rangeland (50.5%) then, rainfed (36.4%), week forest land (3.2%), irrigated land (0.7%) and other various lands (rock out crop and lake) (9.2%). Each land characteristic is also considered as a thematic layer in geographical information systems (GIS) process. After combination of the layers, soil erosion risk map was produced. The results showed that 44.4% of the study area is at high soil erosion risk, whereas 42% of the study area is insignificantly and slightly...

Topsis based Taguchi method for multi-response simulation optimization of flexible manufacturing system

Proceedings of the Winter Simulation Conference 2014, 2014

Land Degradation and Desertification: Assessment, Mitigation and Remediation, 2010

The main objective of the study was to find out the effects of various organic matter sources suc... more The main objective of the study was to find out the effects of various organic matter sources such as bio-solid (BS) and tea waste (TW) on macro nutrient content of eroded soils. In order to determine different soil erodibility levels (slightly, moderately and severely), erosion ratio (ER) and soil erodibility factor (K) parameters were used. Soil samples used in this research were taken from bulk surface (0-20 cm depth) located on agricultural lands of Asagi Aksu village that is 20 km far from Samsun province in the north part of Turkey. These lands have been used as agricultural activity. Some properties of the soil classified as Vertic calciudoll were determined as follows; fine in texture, organic matter content varies between 0.83% and 0.90%. In addition, pH and EC values of these soils are 8.0-8.1 and 0.64-0.79 dSm −1 respectively. This study was conducted by applying four different doses of BS and TW (0%, 2%, 4% and 6%) in eroded soils under greenhouse condition. Each treatment was replicated three times in a split block design. After 18 weeks incubation period associated parameters were determined in all pots. According to analysis

Materials Science and Engineering: A, 2006

Quantitative image analysis was used to study the effect of the powder forming method on the popu... more Quantitative image analysis was used to study the effect of the powder forming method on the population of pull-out flaws for polished surfaces of dense alumina ceramics. By comparing the area fractions, the size distributions and the extreme values of the pull-out areas it was concluded that slip casting with dispersed slips resulted in significantly fewer and smaller pull-outs compared to slip casting with flocculated slips or powder pressing. The implications of these observations for the effect of the powder forming method on the strength of alumina ceramics are discussed.

Journal of the European Ceramic Society, 2007

This study used quantitative image analysis to examine the effect of powder forming method on a p... more This study used quantitative image analysis to examine the effect of powder forming method on a population of dense heterogeneities that could be imaged in partially sintered alumina using optical microscopy. Powder pressing resulted in a higher area fraction of dense heterogeneities than slip casting. Extreme value analysis was used to predict the size of the largest heterogeneity in the populations and assess the processing methods. Powder pressing resulted in the largest extreme value estimate. The results are interpreted in terms of the effect of the forming method on particle packing and the possible effect of the dense heterogeneities on mechanical strength.

International Journal of Production Research, 2006

Geomicrobiology Journal, 2013

Environmental Monitoring and Assessment, 2009