Lotfısadıgh, Bahram

Profile Picture
Profile URL
https://hdl.handle.net/20.500.14411/7762
Name Variants
Lotfisadigh, B.
Lotfısadıgh, Bahram
Bahram, Lotfısadıgh
Lotfisadigh, Bahram
L.,Bahram
B.,Lotfisadigh
L., Bahram
Bahram, Lotfisadigh
B., Lotfisadigh
B.,Lotfısadıgh
Lotfısadıgh,B.
Lotfisadigh,B.
Sadigh, Bahram Lotfi
Job Title
Doktor Öğretim Üyesi
Email Address
bahram.lotfisadigh@atilim.edu.tr
Main Affiliation
Manufacturing Engineering
Status
Former Staff
Website
ORCID ID
Scopus Author ID
Turkish CoHE Profile ID
Google Scholar ID
WoS Researcher ID

Sustainable Development Goals

NO POVERTY1
NO POVERTY
0
Research Products
ZERO HUNGER2
ZERO HUNGER
0
Research Products
GOOD HEALTH AND WELL-BEING3
GOOD HEALTH AND WELL-BEING
1
Research Products
QUALITY EDUCATION4
QUALITY EDUCATION
0
Research Products
GENDER EQUALITY5
GENDER EQUALITY
0
Research Products
CLEAN WATER AND SANITATION6
CLEAN WATER AND SANITATION
0
Research Products
AFFORDABLE AND CLEAN ENERGY7
AFFORDABLE AND CLEAN ENERGY
0
Research Products
DECENT WORK AND ECONOMIC GROWTH8
DECENT WORK AND ECONOMIC GROWTH
0
Research Products
INDUSTRY, INNOVATION AND INFRASTRUCTURE9
INDUSTRY, INNOVATION AND INFRASTRUCTURE
6
Research Products
REDUCED INEQUALITIES10
REDUCED INEQUALITIES
0
Research Products
SUSTAINABLE CITIES AND COMMUNITIES11
SUSTAINABLE CITIES AND COMMUNITIES
1
Research Products
RESPONSIBLE CONSUMPTION AND PRODUCTION12
RESPONSIBLE CONSUMPTION AND PRODUCTION
1
Research Products
CLIMATE ACTION13
CLIMATE ACTION
0
Research Products
LIFE BELOW WATER14
LIFE BELOW WATER
0
Research Products
LIFE ON LAND15
LIFE ON LAND
1
Research Products
PEACE, JUSTICE AND STRONG INSTITUTIONS16
PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
PARTNERSHIPS FOR THE GOALS17
PARTNERSHIPS FOR THE GOALS
0
Research Products
This researcher does not have a Scopus ID.
This researcher does not have a WoS ID.
Scholarly Output

22

Articles

12

Views / Downloads

151/2174

Supervised MSc Theses

5

Supervised PhD Theses

1

WoS Citation Count

234

Scopus Citation Count

280

Patents

0

Projects

0

WoS Citations per Publication

10.64

Scopus Citations per Publication

12.73

Open Access Source

5

Supervised Theses

6

JournalCount
Machining Science and Technology3
International Journal of Computer Integrated Manufacturing2
Procedia CIRP2
The International Journal of Advanced Manufacturing Technology2
Artificial Intelligence for Engineering Design, Analysis and Manufacturing: AIEDAM1
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Scholarly Output Search Results

Now showing 1 - 10 of 22
  • Thumbnail Image
    Article
    Citation - WoS: 12
    Citation - Scopus: 19
    An Ontology-Based Multi-Agent Virtual Enterprise System (omave): Part 1: Domain Modelling and Rule Management
    (Taylor & Francis Ltd, 2017) Sadigh, Bahram Lotfi; Unver, Hakki Ozgur; Nikghadam, Shahrzad; Dogdu, Erdogan; Ozbayoglu, A. Murat; Kilic, S. Engin
    New advancements in computers and information technologies have yielded novel ideas to create more effective virtual collaboration platforms for multiple enterprises. Virtual enterprise (VE) is a collaboration model between multiple independent business partners in a value chain and is particularly suited to small and medium-sized enterprises (SMEs). The most challenging problem in implementing VE systems is ineffcient and inFLexible data storage and management techniques for VE systems. In this research, an ontology-based multi-agent virtual enterprise (OMAVE) system is proposed to help SMEs shift from the classical trend of manufacturing part pieces to producing high-value-added, high-tech, innovative products. OMAVE targets improvement in the FLexibility of VE business processes in order to enhance integration with available enterprise resource planning (ERP) systems. The architecture of OMAVE supports the requisite FLexibility and enhances the reusability of the data and knowledge created in a VE system. In this article, a detailed description of system features along with the rule-based reasoning and decision support capabilities of OMAVE system are presented. To test and verify the functionality and operation of this system, a sample product was manufactured using OMAVE applications and tools with the contribution of three SMEs.
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    Article
    Citation - WoS: 13
    Citation - Scopus: 14
    Integration of Psychological Parameters Into a Thermal Sensation Prediction Model for Intelligent Control of the Hvac Systems
    (Elsevier Science Sa, 2023) Turhan, Cihan; Ozbey, Mehmet Furkan; Lotfi, Bahram; Akkurt, Gulden Gokcen; Gökçen Akkurt, Gülden
    Conventional thermal comfort models take physiological parameters into account on thermal comfort models. On the other hand, psychological behaviors are also proven as a vital parameter which affects the thermal sensation. In the literature, limited studies which combine both physiological and psychological parameters on the thermal sensation models are exist. To this aim, this study develops a novel Thermal Sensation Prediction Model (TSPM) in order to control the HVAC system by considering both parameters. A data-driven TSPM, which includes Fuzzy Logic (FL) model, is developed and coded using Phyton language by the authors. Two physiological parameters (Mean Radiant Temperature and External Temperature) and one psychological parameter (Emotional Intensity Score (EIS) including Vigour, Depression, Tension with total of 32 subscales) are selected as inputs of the model. Besides the physiological parameters which are decided intentionally considering a manual ventilated building property, the most influencing three sub- psychological parameters on thermal sensation are also selected in the study. While the physiological parameters are measured via environmental data loggers, the psychological parameters are collected simultaneously by the Profile of Mood States questionnaire. A total of 1159 students are participated to the questionnaire at a university study hall between 15th of August 2021 and 15th of September 2022. The results showed that the novel model predicted Thermal Sensation Vote (TSV) with an accuracy of 0.92 of R2. The output of this study may help to develop an integrated Heating Ventilating and Air Conditioning (HVAC) system with Artificial Intelligence - enabled Emulators that also includes psychological parameters.
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    Master Thesis
    İç Ortamda Ortalama Radyan Sıcaklığını Elde Etmek için Farklı Yöntemlerin Doğruluğunun Karşılaştırılması
    (2021) Özbey, Mehmet Furkan; Turhan, Cihan; Lotfısadıgh, Bahram
    Amerikan Isıtma Soğutma ve Klima Mühendisleri Birliği (ASHRAE), ısıl konforu bir kişinin bulunduğu ortamdaki memnuniyetini ifade eden öznel ve zihinsel değerlendirme ile elde edilen zihin koşulları olarak tanımlanmıştır. Isıl konfor, geleneksel olarak Fanger'in Ortalama Tahmini Oy (PMV) / Memnuniyetsizliklerin Tahmini Yüzdesi (PPD) metodu ve kişilerin davranışlarını da içeren adaptif ısıl konfor metotları ile elde edilmektedir. Isıl konfor parametreleri kişisel parametreler (giysi değeri ve metabolizma hızı) ve çevresel parametreler (hava sıcaklığı, bağıl nem, hava hızı ve ortalama radyan sıcaklığı) olarak üzere iki farklı kategoride ele almaktadır. Bu parametreler arasında, Ortalama Radyan Sıcaklık ölçülmesinin ve hesaplanmasının karmaşık olmasından dolayı elde edilmesi zor bir faktördür. İç ortamlarda ortalama radyan sıcaklığı elde etme yaklaşımları hesaplama yöntemleri, ölçüm yöntemleri ve varsayımlar gibi farklı yöntemlere dayanmaktadır. Ancak hesaplama yöntemlerinin karmaşık olması ve ölçüm yöntemleri için kullanılacak ölçüm aletlerinin pahalı ve elde edilmesi zor araçlar olması araştırmacıları doğruluğu kesin olmayan varsayımlara yönlendirmektedir. Bu nedenle, bu çalışmanın amacı ortalama radyan sıcaklığın elde edilme yöntemlerinin ölçüm yöntemlerinden birisi olan ve bu çalışma için üretilen küre termometresini referans alıp diğer metotlar ile karşılaştırılarak tüm yöntemlerin doğruluğunu bulmaktır. Bu çalışmada Köppen- Geiger sınıflandırmasına göre Csb tipi iklim bölgesinde bulunan bir test odası seçilmiştir ve ortalama radyatif sıcaklığı elde etmek için kullanılan 2 farklı hesaplama yöntemi ve 8 farklı varsayım yerinde ölçümle referans metodu ile karşılaştırılmıştır. Sonuçlar, ortalama radyan sıcaklığı elde etmek için varsayımların veya hesaplama yöntemlerinin kullanılmasının, referans yönteme kıyasla %9,1'e varan bir hataya neden olduğunu ortaya koydu.
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    Conference Object
    Citation - Scopus: 1
    Ontology Based Virtual Enterprise System Domain Modeling
    (DEStech Publications Inc., 2014) Lotfi Sadigh,B.; Ünver,H.Ö.; Dogdu,E.; Kiliç,S.E.
    A virtual enterprise (VE) is a product oriented temporary consortium which forms a collaboration platform to fulfil a specific common purpose (typically to create a product) by benefiting from various capabilities of multiple VE partner enterprises. VE lifecycle consists of 3 distinct phases including VE Formation, Operation and Dissolution. VE partner enterprises are selected from virtual breeding environment (VBE) based on specific criteria considering the new VE project specifications. In order to select the most appropriate partners for the forthcoming VE project, it is required to have comprehensive information regarding the VBE members, their current conditions, capabilities, capacities and their past performances. This database continuously changes and it is dynamic. Ontologies and the corresponding knowledge bases provide the best tools for modelling such complex domain knowledge and highly dynamic data requirements. Ontologies not only help model and capture complex domain knowledge, but also improve the sharing and reusability of data and knowledge providing a suitable environment for software agents and human communications. The VE system must be able to demonstrate what types of resources exist, where they are located, and how much resource capacity is available to be used by the consortium. In this paper a pilot Virtual Enterprise system model developed for OSTIM organized industrial park in Ankara will be presented in detail. The objective of this system model is to enable SMEs in the region to collaborate effectively in order to produce eco-friendly high value added products. © Copyright 2014 by DEStech Publications, Inc. All rights reserved.
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    Article
    Citation - WoS: 41
    Citation - Scopus: 42
    Enhancing Machining Efficiency of Ti-6al Through Multi-Axial Ultrasonic Vibration-Assisted Machining and Hybrid Nanofluid Minimum Quantity Lubrication
    (Elsevier Sci Ltd, 2024) Namlu, Ramazan Hakki; Lotfi, Bahram; Kilic, S. Engin
    Ti-6Al-4V offers a balance of good strength with lightweight properties. Yet, Ti-6Al-4V poses machining challenges, including low thermal conductivity, chemical adhesion to cutting tools, and chip removal difficulties. To improve machining efficiency, Ultrasonic Vibration-Assisted Machining (UVAM) has emerged as a promising approach. UVAM has demonstrated reduced tool wear, cutting forces, and improved surface quality compared to Conventional Machining (CM). Additionally, Minimum Quantity Lubrication (MQL) methods offer sustainable coolant alternatives, with recent research focusing on Nanofluid-MQL (NMQL) and Hybrid Nanofluid-MQL (HNMQL) for enhanced performance. Although there exists a body of literature showcasing the promising effects of UVAM and MQL methods individually, comprehensive investigations into the synergistic effects of these methodologies remain limited. This study addresses these critical research gaps by conducting a systematic examination of combined application of multi-axial UVAM and HNMQL. Specifically, it delves into the comparison of different vibration directions within UVAM, evaluates the effectiveness of UVAM when combined with cutting fluids incorporating Al2O3 and CuO nanoparticles in NMQLs and HNMQLs, and contrasts these novel approaches with conventional machining methods. The study unfolds in three distinct stages. The first stage examines the ultrasonic cutting mechanism and its combined application with the MQL technique. In the second stage, the study investigates the physical properties of the cutting fluids, including contact angle and surface tension. The final stage encompasses slot milling operations, where an array of parameters such as cutting forces, surface roughness, surface topography, surface texture, and the occurrence of burr formations are rigorously analyzed. The results demonstrate that the combination of multi-axial UVAM with HNMQL yields substantial advantages over traditional machining methods. Notably, it leads to a remarkable reduction in cutting forces (up to 37.6 %) and surface roughness (up to 37.4 %). Additionally, this combination engenders the production of highly homogeneous and uniform surface textures, characterized by minimal surface defects and a significantly diminished occurrence of burr formations. These findings underscore the potential of multi-axial UVAM combined with HNMQL as a promising approach in enhancing the machining of Ti-6Al-4V, thus offering a pathway to enhance the efficiency and precision of aerospace component manufacturing processes.
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    Conference Object
    Citation - WoS: 20
    Citation - Scopus: 26
    An Experimental Study on Surface Quality of Al6061-T6 in Ultrasonic Vibration-Assisted Milling with Minimum Quantity Lubrication
    (Elsevier Science BV, 2022) Namlu, Ramazan Hakki; Yilmaz, Okan Deniz; Lotfisadigh, Bahram; Kilic, S. Engin
    Al6061-T6 is frequently used in the automotive and aerospace industries, where milling is an essential process, due to its high strength-to-weight ratio. In order to achieve improved surface quality in milling, Ultrasonic Vibration-Assisted Milling (UVAM) has been introduced recently. Besides, Minimum Quantity Lubrication (MQL) is another advanced method to enhance the surface properties of the cutting by improving the coolant performance. However, the effects of simultaneous implementation of UVAM and MQL methods has not yet been studied sufficiently. This paper investigates the effects of applying UVAM in tandem with MQL in cutting of Al6061-T6. The results showed that surface quality enhanced with this combination. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0)
  • Thumbnail Image
    Article
    Citation - WoS: 12
    Citation - Scopus: 13
    Predictive Models for Mechanical Properties of Expanded Polystyrene (eps) Geofoam Using Regression Analysis and Artificial Neural Networks
    (Springer London Ltd, 2022) Akis, E.; Guven, G.; Lotfisadigh, B.
    Initial elastic modulus and compressive strength are the two most important engineering properties for modeling and design of EPS geofoams, which are extensively used in civil engineering applications such as light-fill material embankments, retaining structures, and slope stabilization. Estimating these properties based on geometric and physical parameters is of great importance. In this study, the compressive strength and modulus of elasticity values are obtained by performing 356 unconfined compression tests on EPS geofoam samples with different shapes (cubic or disc), dimensions, loading rates, and density values. Using these test results, the mechanical properties of the specimens are predicted by linear regression and artificial neural network (ANN) methods. Both methods predicted the initial modulus of elasticity (E-i), 1% strain (sigma(1)), 5% strain (sigma(5)), and 10% strain (sigma(10)) strength values on a satisfactory level with a coefficient of correlation (R-2) values of greater than 0.901. The only exception was in prediction of sigma(1) and E-i in disc-shaped samples by linear regression method where the R-2 value was around 0.558. The results obtained from linear regression and ANN approaches show that ANN slightly outperform linear regression prediction for E-i and sigma(1) properties. The outcomes of the two methods are also compared with results of relevant studies, and it is observed that the calculated values are consistent with the results from the literature.
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    Master Thesis
    Ayrık Üretim Sistemlerinde Kestirimci Bakım için Akıllı Süreç Planlama Uygulaması
    (2022) Al-humaırı, Elaf Rıyadh Resen; Lotfısadıgh, Bahram; Amınbakhsh, Saman
    Sıkı küresel pazar rekabeti ve sürekli değişen müşteri talepleri, üretim işletmelerini esnek üretim sistemlerine doğru itmektedir. Bu şekilde, süreç planlama ve çizelgeleme adımları üreticiler için gerçekten çok önemlidir. Özellikle hacim ve ürün tipi esnekliği olan esnek atölyelerde bu süreçler daha da kritik hale geliyor. 'Endüstri 4.0' adı verilen yeni bir sanayi devrimi, işletmelerin bu ezici rekabet baskısı ile yüzleşmelerini desteklemek ve süreç planlama ve çizelgeleme süreçlerinin verimliliğini artırmak için bilgisayar ve bilgi teknolojilerini üretim sistemleriyle entegre ederek yeni teknolojik olanaklar getiriyor. Etmen tabanlı sistemler, üretim sistemlerinin sanallaştırılması, siber-fiziksel katmanların oluşturulmasıyla sistem simülasyonu, dijital ikizler ve diğerleri gibi bu teknolojilerden bazıları literatürde çeşitli araştırmalarda çalışılmış ve geliştirilmiş olarak adlandırılabilir. Bu araştırmada, üretim alanının ontolojik modellemesi ve muhakeme kurallarının süreç planlama aşamasına bir çözüm olarak Lekin çizelgeleme programı ile entegre edilerek yeni bir metodoloji önerilmiştir. Bu tezde, önce talaşlı imalat işlemleri için geliştirilen ontoloji etki alanı modeli anlatılmış, daha sonra tasarlanarak eklenen muhakeme kuralları ve SPARQL sorguları detaylı olarak anlatılmıştır. Son olarak, Lekin programı yerleşik sezgisellerinden elde edilen çizelgeleme sonuçları açıklanmıştır.
  • Thumbnail Image
    Article
    Citation - WoS: 28
    Citation - Scopus: 33
    An Experimental Investigation on the Effects of Combined Application of Ultrasonic Assisted Milling (uam) and Minimum Quantity Lubrication (mql) on Cutting Forces and Surface Roughness of Ti-6al
    (Taylor & Francis inc, 2021) Namlu, Ramazan Hakki; Sadigh, Bahram Lotfi; Kilic, Sadik Engin
    Ti-6Al-4V is widely used in aerospace, medical and defense industries where materials with superior characteristics are needed. However, Ti-6Al-4V is categorized as a difficult-to-cut material, and machining of this alloy is highly challenging. Ultrasonic Assisted Milling (UAM) is a quite recent method to facilitate the machining of difficult-to-cut materials. This method has numerous advantages over the Conventional Milling (CM) method, such as reduced cutting forces and increased surface quality. Besides, Minimum Quantity Lubrication (MQL) is an alternative cooling method to enhance the process efficiency with respect to conventional cooling methods. Cutting force and surface roughness are essential measures to evaluate the cutting performance of a machining process. However, the simultaneous effects of implementing MQL and ultrasonic vibrations in milling operations are not much researched yet. In this study, the combined effects of UAM and MQL on cutting forces and surface roughness during the machining of Ti-6AL-4V are investigated. Results show that the combination of MQL and UAM enhances the cutting forces in rough cutting operations and the surface roughness in both finish and rough cutting operations significantly compared to conventional processes. Consequently, it is concluded that simultaneous implementation of UAM and MQL enhances overall cutting performance in end-milling operation of Ti-6Al-4V.
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    Master Thesis
    Yazılım Araçları Kullanarak Kablaj Tasarımı ve Maliyetanalizinin Modellenmesi ve Optimizasyonu
    (2021) Tankut, Mehmet Kemal; Lotfısadıgh, Bahram; Kara, Ali
    Bir kablaj elektriksel gücü, sinyali veya veriyi iki veya daha fazla kaynak arasında ileten kablo ağı veya kablo montajlarına denir. Bir kablaj aynı zamanda, konnektörleri, arkalıkları, iletken telleri, koruyucu kılıfları, branşmanları, metal örgüleri, kablo ceketlerini ve birleştirici kılıfları gibi bazı alt bileşenler içerebilir. Bir kablaj çeşitli materyal ve alt bileşen içerebildiği için gerekli malzemelerin kablaj tasarımı ve imalatı sürecinde belirlenmesi kritiktir. Bu nedenle, uygun bileşenlerin seçimi, standartlar ve veri sayfalarına göz atmak için çok fazla zaman gerektirir. Zaman kayıpları, büyük ölçüde tasarımcıların deneyim düzeyine ve istenilen kablajın karmaşıklığına bağlıdır. Bu araştırmada, kablo demeti tasarımı sırasında zaman kayıplarını azaltmak ve bu arada bileşen seçimlerinde hata riskini azaltmak için yazılım geliştirilmiştir. Bu çalışma, kablaj karmaşıklığı ve tasarımcı tecrübesi göz önünde bulundurularak, kablaj tasarım sürecini geliştirmeye yönelik böyle bir girişimin etkilerini ve sonuçlarını özetlemektedir. Deneysel sonuçlara göre, her tasarımcı için projelerde aylık harcanan zaman hesaplanmış ve bir maliyet modeli geliştirilmiştir. Son olarak, hazırlanan yazılımın katkısı değerlendirilmiş ve sonuçlar, bu yazılımın kablaj tasarım ve geliştirme sürecinde, kablaj karmaşıklığı ve kullanıcı deneyimi ne olursa olsun uygulanmasının faydalı olduğunu göstermektedir.