Pamukkale University Journal of Engineering Sciences, 2021
Bu çalışmada, Niğde-Ulukışla yöresine ait Pb-Zn kompleks cevherinin optimum flotasyon şartları ar... more Bu çalışmada, Niğde-Ulukışla yöresine ait Pb-Zn kompleks cevherinin optimum flotasyon şartları araştırılmıştır. Deneysel çalışmalarda kullanılacak olan cevher numunesinin serbestleşme tane boyutu (d80) belirlenmiş ve mineralojik analizleri gerçekleştirilmiştir.
Pamukkale University Journal of Engineering Sciences, 2019
Tüm telekomünikasyon operatörleri için baz istasyonları önemli bir yer teşkil etmektedir. Verimli... more Tüm telekomünikasyon operatörleri için baz istasyonları önemli bir yer teşkil etmektedir. Verimli çalışan baz istasyonları gelir kaybının önüne geçmekte olup şirkete prestij kazandırmaktadır. Bu çalışma, Türkiye'nin önde gelen GSM operatörlerinden birinin elektrik kesintisi durumunda taşınabilir jenaratörlerin baz istasyonlarına dağıtımının planlaması ile ilgilenmektedir. Mersin'in belirli bir bölgesinde sık sık meydana gelen elektrik kesintileri müşteri şikayetlerinin yanı sıra firma için gelir kaybına neden olmaktadır. Elektrik kesintisi yaşandıktan sonra, o baz istasyonu için akü devreye girmektedir. Fakat akünün ömrü fazla uzun değildir ve bazen kesinti süresince yeterli olmamaktadır. Akü bittikten sonra baz istasyonunun çalışabilmesi için sabit jeneratörün devreye girmesi beklenmektedir. Öte yandan, sabit jeneratörlerin maliyetleri yüksek olduğundan her baz istasyonu bu jeneratöre sahip değildir. Bu nedenle firma sınırlı sayıdaki taşınabilir jeneratörleri kullanarak dur...
Advances in Intelligent Systems and Computing, 2020
In this study, optimum dimensioning of a reinforced concrete cantilever retaining wall under stat... more In this study, optimum dimensioning of a reinforced concrete cantilever retaining wall under static loads was made by developing a method using the Jaya algorithm. During the optimization process, the retaining wall stability checks, crosssection capacities and controls including reinforced concrete structural design rules were made. With the optimum design, it is aimed that the retaining wall crosssection dimensions reach the optimum value. The total material cost is defined as the objective function and the cross-section dimensions are defined to be variable. In order to determine the effect of the front encasement (toe projection), different design limits are entered into the program, and program outputs are examined. The results of the analysis showed that the standard deviation value increases as the design limits get narrow. The dimensioning of the retaining wall was made according to TS 7994 (Soil Resistance Structures; Classification, Properties and Project Design Principles) and the reinforced concrete design was made according to TS 500 (Design and Construction Rules of Reinforced Concrete Structures) rules. The Jaya optimization method has been found to be superior to the existing methods, and it has been understood that it is appropriate to use the method in the optimum design of the retaining wall.
Academic Platform Journal of Engineering and Science, 2021
In this study, grinding + flotation experiments were performed on the sample of complex Pb-Zn sul... more In this study, grinding + flotation experiments were performed on the sample of complex Pb-Zn sulphide ore taken from Niğde (Ulukışla-Madenköy) region in Turkey. According to the mineralogical analysis of the ore sample used in experimental studies, it was determined that the ore composition contains calcite, quartz, pyrite, chalcopyrite, hematite, goethite, limonite, gypsum, galena, sphalerite, jarosite, arsenopyrite and marcasite minerals. In addition, Au and Ag grains were found to be inclusions in hematite, goethite and jarosite minerals. The experiments were carried out at a solid ratio of 30%, a flow rate of 10 L/min, a stirring rate of 1250 rpm and pH = 9. In flotation tests, lime is used as the pH regulator, zinc sulphate, sodium silicate as the depressant, sodium isobutyl dithiophosphine as the collector and methyl isobutyl carbinol as the frother. In the flotation studies, the effect of Aerophine 3418A collector dosage on flotation was investigated. As a result, a lead concentrate of 55.13% Pb was obtained and it was found that this concentrate contained 2489 ppm of Ag. The amount of Aerophine 3418A collector was determined as 10 g/t.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Pamukkale University Journal of Engineering Sciences, 2019
Base stations are very important for all GSM operators. Efficient base stations prevent income lo... more Base stations are very important for all GSM operators. Efficient base stations prevent income loss while bringing prestige to the company. This study deals with the problem of transportation planning of portable generators during electricity failure for a leading Turkish GSM operator. There are often electricity failures in a particular area of Mersin which cause not only customer complaints but also income loss for the company. After an electricity failure, a battery steps in for that station. However, the lifetime of battery is limited and sometimes not enough during the failure. In that case, a fixed generator could step in to give service properly. Unfortunately, because of the high cost of fixed generators, not all base stations have a fixed generator. Therefore, the company tries to interfere this problem by using limited number of portable generators. Field operation teams transport and set up these portable generators to the sites with electricity failure before the battery dies. The problem is to schedule the transportation of portable generators to the base stations with electricity failure. In this study, composite dispatching rule, one of the scheduling algorithms, is used to solve this planning problem effectively. An Excel based decision support system has been developed for field operation team. Whenever a failure occurs, after inputting necessary information to the Excel, transportation schedule for each team could be easily obtained by the company experts.
Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, ... more Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, we aimed to investigate the appropriateness of TM requests in our hospital. Patients in the study were identified from the TM requests for 3 months between June-August 2004, using the laboratory database. A total of 2249 patients (1351 men, 898 women) were included in the study and there were 6570 TM requests. The number of requests were 1050 (16%) for Carbohydrate Antigen 19-9, 993 (15.1%) for Cancer Antigen 125 , 941 (14.3%) for Prostate Specific Antigen, 921 (14%) for free PSA, 925 (14.1%) for Cancer Antigen 15-3, 788 (12%) for Alphafetoprotein, 730 (11.1%) for Carcinoembryonic Antigen and 222 (3.4%) for AFP / Human Chorionic Gonadotrophin. Our findings support the idea that for the evidence-based use of TM requests the education of clinical staff is required. Clear clinical guidelines including recommendations about the appropriate use of TM can be useful for this education process. Careful audit studies are also useful to determine the impact of these guidelines on the practice of evidence-based laboratory medicine.
BACKGROUND Innovation in design depends on successful concept generation. The ideation stage of d... more BACKGROUND Innovation in design depends on successful concept generation. The ideation stage of design is intended to produce multiple, varied concepts from which to develop and choose. Often, instruction on idea generation methods is not offered in engineering classes; however, when taught, it is commonly through techniques like brainstorming, which lacks specific ways to generate designs. Further, existing ideation strategies are not based on evidence from designers or rigorous testing through empirical studies. PURPOSE This study investigated how engineering students and practitioners generated ideas. We focused on how designers used product characteristics to define concepts, and how previous concepts were transformed into new solutions by modifying their characteristics. Our methodology is based on our previous work identifying Design Heuristics in engineering solutions, defined as cognitive prompts that facilitate exploration of multiple designs during concept generation. METHOD Think-aloud recordings and concept sketches were collected from 36 engineering students and practitioners (with varying levels of experience) as they generated ideas for a novel design task in a laboratory setting. These data, along with retrospective interviews, were analyzed for the ideation strategies evident in the participants' solutions. RESULTS This study revealed evidence for over 60 strategies for concept generation during the ideation stage. Participants generated novel concepts and proposed concept modifications, and specific Design Heuristics were observed in their designs. The results suggest instruction on Design Heuristics can aid in effective idea generation. CONCLUSIONS This protocol study of engineering designers provides a collection of heuristics observed in practice that offers new methods for students and practitioners to explore design spaces. The Design Heuristics identified in this and previous work can potentially be learned and then incorporated into the practice of engineering students and practitioners.
Thermal Energy Storage (TES) provides us with a flexible heating and/or cooling tool to combat gl... more Thermal Energy Storage (TES) provides us with a flexible heating and/or cooling tool to combat global warming through conserving energy while utilising natural renewable energy resources. This paper aims to show how CO 2 emissions can be decreased by utilising different TES concepts in Turkey. The first project is for the heating and cooling of a supermarket using Aquifer Thermal Energy Storage (ATES) in Mersin. With a 60% higher Coefficient of Performance (COP), the yearly CO 2 emissions reduction contribution of this project is 113 tonnes. The second project concerns ATES for the heating and cooling of a greenhouse in Adana. The greenhouse was used as a 'solar collector' and source of energy for the ATES system. No fossil fuels were consumed for heating the greenhouse and cooling was made possible with the ATES system. Energy conservation amounted to 68% and CO 2 emissions were reduced by 26 tonnes/year. The third one is a pilot project using TES in microencapsulated phase change materials in a test cabin in Adana with a floor area of 4 m 2. By using a 3.5 kg Phase Change Material (PCM) together with insulation panels in the test cabin, 7% cooling energy and 28% heating energy can be conserved. The corresponding CO 2 emissions reduction would be 0.5 tonnes/year.
Research has shown that cognition often relies on simplified heuristics; however, few studies hav... more Research has shown that cognition often relies on simplified heuristics; however, few studies have explored the role of heuristics in design. We propose that designers utilize specific heuristics to explore the problem space of potential concepts, leading to the generation of novel and creative solutions. Design heuristic use in the early stages of product conception was examined through a case study of an expert industrial designer working on a real-world project. Sequences of exploratory concept sketches were analyzed for evidence of design heuristic use in generating concepts. This case study uncovers design heuristics that promote variation in concepts and alter existing solutions, supporting the claim that expertise incorporates the use of heuristics to maximize creativity and diversity in designs.
By uncovering the Design Heuristics that engineers use to explore solution spaces, we can provide... more By uncovering the Design Heuristics that engineers use to explore solution spaces, we can provide engineering students and practitioners with a collection of explicit, empirically based strategies to aid their idea generation.[...] it offers a way to teach engineering students specific strategies that will increase their chances of success in generating ideas to solve design problems when they become practicing engineers.
Pamukkale University Journal of Engineering Sciences, 2021
Bu çalışmada, Niğde-Ulukışla yöresine ait Pb-Zn kompleks cevherinin optimum flotasyon şartları ar... more Bu çalışmada, Niğde-Ulukışla yöresine ait Pb-Zn kompleks cevherinin optimum flotasyon şartları araştırılmıştır. Deneysel çalışmalarda kullanılacak olan cevher numunesinin serbestleşme tane boyutu (d80) belirlenmiş ve mineralojik analizleri gerçekleştirilmiştir.
Pamukkale University Journal of Engineering Sciences, 2019
Tüm telekomünikasyon operatörleri için baz istasyonları önemli bir yer teşkil etmektedir. Verimli... more Tüm telekomünikasyon operatörleri için baz istasyonları önemli bir yer teşkil etmektedir. Verimli çalışan baz istasyonları gelir kaybının önüne geçmekte olup şirkete prestij kazandırmaktadır. Bu çalışma, Türkiye'nin önde gelen GSM operatörlerinden birinin elektrik kesintisi durumunda taşınabilir jenaratörlerin baz istasyonlarına dağıtımının planlaması ile ilgilenmektedir. Mersin'in belirli bir bölgesinde sık sık meydana gelen elektrik kesintileri müşteri şikayetlerinin yanı sıra firma için gelir kaybına neden olmaktadır. Elektrik kesintisi yaşandıktan sonra, o baz istasyonu için akü devreye girmektedir. Fakat akünün ömrü fazla uzun değildir ve bazen kesinti süresince yeterli olmamaktadır. Akü bittikten sonra baz istasyonunun çalışabilmesi için sabit jeneratörün devreye girmesi beklenmektedir. Öte yandan, sabit jeneratörlerin maliyetleri yüksek olduğundan her baz istasyonu bu jeneratöre sahip değildir. Bu nedenle firma sınırlı sayıdaki taşınabilir jeneratörleri kullanarak dur...
Advances in Intelligent Systems and Computing, 2020
In this study, optimum dimensioning of a reinforced concrete cantilever retaining wall under stat... more In this study, optimum dimensioning of a reinforced concrete cantilever retaining wall under static loads was made by developing a method using the Jaya algorithm. During the optimization process, the retaining wall stability checks, crosssection capacities and controls including reinforced concrete structural design rules were made. With the optimum design, it is aimed that the retaining wall crosssection dimensions reach the optimum value. The total material cost is defined as the objective function and the cross-section dimensions are defined to be variable. In order to determine the effect of the front encasement (toe projection), different design limits are entered into the program, and program outputs are examined. The results of the analysis showed that the standard deviation value increases as the design limits get narrow. The dimensioning of the retaining wall was made according to TS 7994 (Soil Resistance Structures; Classification, Properties and Project Design Principles) and the reinforced concrete design was made according to TS 500 (Design and Construction Rules of Reinforced Concrete Structures) rules. The Jaya optimization method has been found to be superior to the existing methods, and it has been understood that it is appropriate to use the method in the optimum design of the retaining wall.
Academic Platform Journal of Engineering and Science, 2021
In this study, grinding + flotation experiments were performed on the sample of complex Pb-Zn sul... more In this study, grinding + flotation experiments were performed on the sample of complex Pb-Zn sulphide ore taken from Niğde (Ulukışla-Madenköy) region in Turkey. According to the mineralogical analysis of the ore sample used in experimental studies, it was determined that the ore composition contains calcite, quartz, pyrite, chalcopyrite, hematite, goethite, limonite, gypsum, galena, sphalerite, jarosite, arsenopyrite and marcasite minerals. In addition, Au and Ag grains were found to be inclusions in hematite, goethite and jarosite minerals. The experiments were carried out at a solid ratio of 30%, a flow rate of 10 L/min, a stirring rate of 1250 rpm and pH = 9. In flotation tests, lime is used as the pH regulator, zinc sulphate, sodium silicate as the depressant, sodium isobutyl dithiophosphine as the collector and methyl isobutyl carbinol as the frother. In the flotation studies, the effect of Aerophine 3418A collector dosage on flotation was investigated. As a result, a lead concentrate of 55.13% Pb was obtained and it was found that this concentrate contained 2489 ppm of Ag. The amount of Aerophine 3418A collector was determined as 10 g/t.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Pamukkale University Journal of Engineering Sciences, 2019
Base stations are very important for all GSM operators. Efficient base stations prevent income lo... more Base stations are very important for all GSM operators. Efficient base stations prevent income loss while bringing prestige to the company. This study deals with the problem of transportation planning of portable generators during electricity failure for a leading Turkish GSM operator. There are often electricity failures in a particular area of Mersin which cause not only customer complaints but also income loss for the company. After an electricity failure, a battery steps in for that station. However, the lifetime of battery is limited and sometimes not enough during the failure. In that case, a fixed generator could step in to give service properly. Unfortunately, because of the high cost of fixed generators, not all base stations have a fixed generator. Therefore, the company tries to interfere this problem by using limited number of portable generators. Field operation teams transport and set up these portable generators to the sites with electricity failure before the battery dies. The problem is to schedule the transportation of portable generators to the base stations with electricity failure. In this study, composite dispatching rule, one of the scheduling algorithms, is used to solve this planning problem effectively. An Excel based decision support system has been developed for field operation team. Whenever a failure occurs, after inputting necessary information to the Excel, transportation schedule for each team could be easily obtained by the company experts.
Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, ... more Serum tumor markers may be requested inappropriately by clinicians. In this retrospective study, we aimed to investigate the appropriateness of TM requests in our hospital. Patients in the study were identified from the TM requests for 3 months between June-August 2004, using the laboratory database. A total of 2249 patients (1351 men, 898 women) were included in the study and there were 6570 TM requests. The number of requests were 1050 (16%) for Carbohydrate Antigen 19-9, 993 (15.1%) for Cancer Antigen 125 , 941 (14.3%) for Prostate Specific Antigen, 921 (14%) for free PSA, 925 (14.1%) for Cancer Antigen 15-3, 788 (12%) for Alphafetoprotein, 730 (11.1%) for Carcinoembryonic Antigen and 222 (3.4%) for AFP / Human Chorionic Gonadotrophin. Our findings support the idea that for the evidence-based use of TM requests the education of clinical staff is required. Clear clinical guidelines including recommendations about the appropriate use of TM can be useful for this education process. Careful audit studies are also useful to determine the impact of these guidelines on the practice of evidence-based laboratory medicine.
BACKGROUND Innovation in design depends on successful concept generation. The ideation stage of d... more BACKGROUND Innovation in design depends on successful concept generation. The ideation stage of design is intended to produce multiple, varied concepts from which to develop and choose. Often, instruction on idea generation methods is not offered in engineering classes; however, when taught, it is commonly through techniques like brainstorming, which lacks specific ways to generate designs. Further, existing ideation strategies are not based on evidence from designers or rigorous testing through empirical studies. PURPOSE This study investigated how engineering students and practitioners generated ideas. We focused on how designers used product characteristics to define concepts, and how previous concepts were transformed into new solutions by modifying their characteristics. Our methodology is based on our previous work identifying Design Heuristics in engineering solutions, defined as cognitive prompts that facilitate exploration of multiple designs during concept generation. METHOD Think-aloud recordings and concept sketches were collected from 36 engineering students and practitioners (with varying levels of experience) as they generated ideas for a novel design task in a laboratory setting. These data, along with retrospective interviews, were analyzed for the ideation strategies evident in the participants' solutions. RESULTS This study revealed evidence for over 60 strategies for concept generation during the ideation stage. Participants generated novel concepts and proposed concept modifications, and specific Design Heuristics were observed in their designs. The results suggest instruction on Design Heuristics can aid in effective idea generation. CONCLUSIONS This protocol study of engineering designers provides a collection of heuristics observed in practice that offers new methods for students and practitioners to explore design spaces. The Design Heuristics identified in this and previous work can potentially be learned and then incorporated into the practice of engineering students and practitioners.
Thermal Energy Storage (TES) provides us with a flexible heating and/or cooling tool to combat gl... more Thermal Energy Storage (TES) provides us with a flexible heating and/or cooling tool to combat global warming through conserving energy while utilising natural renewable energy resources. This paper aims to show how CO 2 emissions can be decreased by utilising different TES concepts in Turkey. The first project is for the heating and cooling of a supermarket using Aquifer Thermal Energy Storage (ATES) in Mersin. With a 60% higher Coefficient of Performance (COP), the yearly CO 2 emissions reduction contribution of this project is 113 tonnes. The second project concerns ATES for the heating and cooling of a greenhouse in Adana. The greenhouse was used as a 'solar collector' and source of energy for the ATES system. No fossil fuels were consumed for heating the greenhouse and cooling was made possible with the ATES system. Energy conservation amounted to 68% and CO 2 emissions were reduced by 26 tonnes/year. The third one is a pilot project using TES in microencapsulated phase change materials in a test cabin in Adana with a floor area of 4 m 2. By using a 3.5 kg Phase Change Material (PCM) together with insulation panels in the test cabin, 7% cooling energy and 28% heating energy can be conserved. The corresponding CO 2 emissions reduction would be 0.5 tonnes/year.
Research has shown that cognition often relies on simplified heuristics; however, few studies hav... more Research has shown that cognition often relies on simplified heuristics; however, few studies have explored the role of heuristics in design. We propose that designers utilize specific heuristics to explore the problem space of potential concepts, leading to the generation of novel and creative solutions. Design heuristic use in the early stages of product conception was examined through a case study of an expert industrial designer working on a real-world project. Sequences of exploratory concept sketches were analyzed for evidence of design heuristic use in generating concepts. This case study uncovers design heuristics that promote variation in concepts and alter existing solutions, supporting the claim that expertise incorporates the use of heuristics to maximize creativity and diversity in designs.
By uncovering the Design Heuristics that engineers use to explore solution spaces, we can provide... more By uncovering the Design Heuristics that engineers use to explore solution spaces, we can provide engineering students and practitioners with a collection of explicit, empirically based strategies to aid their idea generation.[...] it offers a way to teach engineering students specific strategies that will increase their chances of success in generating ideas to solve design problems when they become practicing engineers.
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