Kutlucan Görür, M. R. Bozkurt, M. S. Başçil, Feyzullah Temurtaş
Tongue-machine interface (TMI) is a feasible way between the assistive technologies and paralyzed individuals who have lost their abilities to communicate with the environment. Researchers have presented equipment based tongue-machine interfaces to reach a reliable and speedy system. However, this kind of interfaces may occur a way of obtrusive, unattractive and unhygienic for disabled persons. In this research, we intended to propose a natural, unobtrusive and robust glossokinetic potential signals (GKP) based TMI exploring the success of the novel machine learning algorithms. The tongue is bound up with cranial nerves to the brain, which can escape from the spinal cord injuries in general. Moreover, the tongue has highly capable of sophisticated manipulation tasks with less perceived exertion in the oral cavity and gives degrees of privacy. In this study, ten naive healthy subjects have attended who were between 22-34 ages. Decision Tree (DT) and k-Nearest Neighbors (kNN) algorithms were used with Mean-Absolute Value (MAV) and Power Spectral Density (PSD) methods. Moreover, Discrete Wavelet Transform (DWT) was implemented to reveal the theta and delta subbands. In the study, the highest value was provided as 96.77% by the k-Nearest Neighbor algorithm for the best participant. Furthermore, the GKP-based TMI may be an alternative system for the limitations of the brain-computer interfaces. It is well-known that EEG deficits are major concerns for brain-computer interfaces.
{"title":"Tongue-Operated Biosignal over EEG and Processing with Decision Tree and kNN","authors":"Kutlucan Görür, M. R. Bozkurt, M. S. Başçil, Feyzullah Temurtaş","doi":"10.21541/APJES.583049","DOIUrl":"https://doi.org/10.21541/APJES.583049","url":null,"abstract":"Tongue-machine interface (TMI) is a feasible way between the assistive technologies and paralyzed individuals who have lost their abilities to communicate with the environment. Researchers have presented equipment based tongue-machine interfaces to reach a reliable and speedy system. However, this kind of interfaces may occur a way of obtrusive, unattractive and unhygienic for disabled persons. In this research, we intended to propose a natural, unobtrusive and robust glossokinetic potential signals (GKP) based TMI exploring the success of the novel machine learning algorithms. The tongue is bound up with cranial nerves to the brain, which can escape from the spinal cord injuries in general. Moreover, the tongue has highly capable of sophisticated manipulation tasks with less perceived exertion in the oral cavity and gives degrees of privacy. In this study, ten naive healthy subjects have attended who were between 22-34 ages. Decision Tree (DT) and k-Nearest Neighbors (kNN) algorithms were used with Mean-Absolute Value (MAV) and Power Spectral Density (PSD) methods. Moreover, Discrete Wavelet Transform (DWT) was implemented to reveal the theta and delta subbands. In the study, the highest value was provided as 96.77% by the k-Nearest Neighbor algorithm for the best participant. Furthermore, the GKP-based TMI may be an alternative system for the limitations of the brain-computer interfaces. It is well-known that EEG deficits are major concerns for brain-computer interfaces.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133069673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photometric Flicker event, in other words, Temporal Light Modulation occurs at both visually noticeable and unnoticeable levels by human beings. In spite of this, the human brain and body experience some discomfort as a result of the direct or triggering effects of this event or the existing ailments increase. Photometric Flicker event occurs in a wide frequency band. Especially at low frequencies, due to the disease, seizure, disease progression, or headache, visual impairment may directly affect human biology negatively. The diseases most associated with the photometric Flicker event emerged as epilepsy, migraine and vertigo. In addition, unreasonable headache, poor performance in work, loss and errors of perception are frequently reported in the literature. When making lighting design, low and high risk groups should be determined in terms of both users and light sources, and projects should be made in this context. Various methods that do not require medical and / or laboratory research can be used to determine the level of exposure to the Flicker event. In this study, while examining the biological effects of Photometric Flicker, both the methods to easily determine these effects and their levels and what should be done to prevent the users from being adversely affected have been revealed. C YAVUZ Academic Platform Journal of Engineering and Science 9-1, 223-228, 2021 224
{"title":"The Effects of Photometric Flicker on Human and Their Non-Medical Detection Methods","authors":"C. Yavuz, C. A. Tırmıkçı","doi":"10.21541/APJES.833114","DOIUrl":"https://doi.org/10.21541/APJES.833114","url":null,"abstract":"Photometric Flicker event, in other words, Temporal Light Modulation occurs at both visually noticeable and unnoticeable levels by human beings. In spite of this, the human brain and body experience some discomfort as a result of the direct or triggering effects of this event or the existing ailments increase. Photometric Flicker event occurs in a wide frequency band. Especially at low frequencies, due to the disease, seizure, disease progression, or headache, visual impairment may directly affect human biology negatively. The diseases most associated with the photometric Flicker event emerged as epilepsy, migraine and vertigo. In addition, unreasonable headache, poor performance in work, loss and errors of perception are frequently reported in the literature. When making lighting design, low and high risk groups should be determined in terms of both users and light sources, and projects should be made in this context. Various methods that do not require medical and / or laboratory research can be used to determine the level of exposure to the Flicker event. In this study, while examining the biological effects of Photometric Flicker, both the methods to easily determine these effects and their levels and what should be done to prevent the users from being adversely affected have been revealed. C YAVUZ Academic Platform Journal of Engineering and Science 9-1, 223-228, 2021 224","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124780932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work characterizes the various length fluidic oscillators with constant depth and having the same main geometric dimensions. A change in fluidic oscillator's length affects the frequency and sweeping characteristics of the fluidic oscillators. These characteristics were extracted by means of constant temperature anemometry hot-wire measurements and water flow visualizations. A total number of ten fluidic oscillators were compared to the baseline fluidic oscillator design. It was observed that shortening the fluidic oscillator ceases the oscillations after a threshold oscillator length whereas elongating the fluidic oscillator decreases the frequency and sweep angle gradually. Furthermore, the frequency maps obtained from hot-wire measurements for each considered fluidic oscillator design provided overall detail about the frequency of the oscillations for a wide range of flow rate. For a constant supply flow rate where the frequency and the sweep angle of an oscillator is constant, changing the length of a fluidic oscillator will allow varying these characteristics of the oscillator. Thus the oscillator can be tailored for a specific need of an application.
{"title":"Effect of the Oscillator Length on the Characteristics of a Feedback Type Fluidic Oscillator","authors":"Mehmet N. Tomac","doi":"10.21541/apjes.583500","DOIUrl":"https://doi.org/10.21541/apjes.583500","url":null,"abstract":"This work characterizes the various length fluidic oscillators with constant depth and having the same main geometric dimensions. A change in fluidic oscillator's length affects the frequency and sweeping characteristics of the fluidic oscillators. These characteristics were extracted by means of constant temperature anemometry hot-wire measurements and water flow visualizations. A total number of ten fluidic oscillators were compared to the baseline fluidic oscillator design. It was observed that shortening the fluidic oscillator ceases the oscillations after a threshold oscillator length whereas elongating the fluidic oscillator decreases the frequency and sweep angle gradually. Furthermore, the frequency maps obtained from hot-wire measurements for each considered fluidic oscillator design provided overall detail about the frequency of the oscillations for a wide range of flow rate. For a constant supply flow rate where the frequency and the sweep angle of an oscillator is constant, changing the length of a fluidic oscillator will allow varying these characteristics of the oscillator. Thus the oscillator can be tailored for a specific need of an application.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130964543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Addressing the risk management process with a holistic approach, enterprise risk management (ERM) enables efficient business processes to be carried out. Achieving success in time, cost and quality factors for complex projects in the constantly evolving construction industry requires systematic and holistic management approaches. In the management process of the construction projects, managing the possible risks from a holistic perspective is critical to the success and efficiency of the construction projects. However, in the companies operating in the construction sector, the transition steps from project-level risk management to corporate risk management have just begun and the level of maturity has not yet been reached. In this context, the main purpose of this study is to reveal the effect of the existence of the risk manager and corporate risk managament structuring on the corporate risk management maturity level of the construction companies. For this purpose, six main factors (stability of the board and senior management, having corporate risk management, risk identification, analysis and response, integrating corporate risk management into business processes, setting targets, and sufficient resources) are obtained as a result of a comprehensive literature review and a survey field study was organized. The data were analyzed with descriptive statistics and ANOVA analysis methods. As a result of the study carried out, the effect of the presence of the risk manager on the maturity level of corporate risk management in the construction companies and the impact and importance levels of the basic factors on the maturity of ERM were determined and compared. This study shed light on future studies to be done by examining the conceptual framework regarding ERM maturity levels in production companies.
{"title":"Yapım Firmalarının Kurumsal Risk Yönetimi Olgunluğunda Risk Yöneticisinin Rolü","authors":"Tugce Ercan, Kübra Ari","doi":"10.21541/apjes.579463","DOIUrl":"https://doi.org/10.21541/apjes.579463","url":null,"abstract":"Addressing the risk management process with a holistic approach, enterprise risk management (ERM) enables efficient business processes to be carried out. Achieving success in time, cost and quality factors for complex projects in the constantly evolving construction industry requires systematic and holistic management approaches. In the management process of the construction projects, managing the possible risks from a holistic perspective is critical to the success and efficiency of the construction projects. However, in the companies operating in the construction sector, the transition steps from project-level risk management to corporate risk management have just begun and the level of maturity has not yet been reached. In this context, the main purpose of this study is to reveal the effect of the existence of the risk manager and corporate risk managament structuring on the corporate risk management maturity level of the construction companies. For this purpose, six main factors (stability of the board and senior management, having corporate risk management, risk identification, analysis and response, integrating corporate risk management into business processes, setting targets, and sufficient resources) are obtained as a result of a comprehensive literature review and a survey field study was organized. The data were analyzed with descriptive statistics and ANOVA analysis methods. As a result of the study carried out, the effect of the presence of the risk manager on the maturity level of corporate risk management in the construction companies and the impact and importance levels of the basic factors on the maturity of ERM were determined and compared. This study shed light on future studies to be done by examining the conceptual framework regarding ERM maturity levels in production companies.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125657388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mobil iletisiminin hizli gelismesiyle internet iceriginin cogu gunumuzde hucresel aglar ile saglanmaktadir. Hucresel aglarda yasanan tikaniklik sirasinda kullanilan algoritmalar paket gecikmesi, kuyruk tasmasi ve darbogaz problemlerini cozmeye calismaktadirlar. LTE aglarinda remote-host ile PG-W dugumu arasindaki veri transferi yuksek hiz gerektirmekte bu da hucresel agin calisma hizini dogrudan etkilemektedir. Dogru bir kuyruk yonetim algoritmasinin secilmesi LTE hucresel agi icin kritik bir onem kazanmaktadir. Bu calismada LTE aglarinda remote-host ile PG-W arasinda calisan aktif kuyruk yonetim algoritmalari olan RED, CoDel, Pie ve pFIFO’nun performanslarinin, uctan uca ortalama verim, gecikme ve paket dusurme oranlari uzerindeki etkisi karsilastirmali olarak incelenmistir ve sonuclari degerlendirilmistir.
{"title":"LTE Ağlarda Remote-Host ile PG-W arasındaki Kuyruk Yönetim Algoritmalarının Performans Analizi","authors":"Muhammet Çakmak, Zafer Albayrak","doi":"10.21541/apjes.662677","DOIUrl":"https://doi.org/10.21541/apjes.662677","url":null,"abstract":"Mobil iletisiminin hizli gelismesiyle internet iceriginin cogu gunumuzde hucresel aglar ile saglanmaktadir. Hucresel aglarda yasanan tikaniklik sirasinda kullanilan algoritmalar paket gecikmesi, kuyruk tasmasi ve darbogaz problemlerini cozmeye calismaktadirlar. LTE aglarinda remote-host ile PG-W dugumu arasindaki veri transferi yuksek hiz gerektirmekte bu da hucresel agin calisma hizini dogrudan etkilemektedir. Dogru bir kuyruk yonetim algoritmasinin secilmesi LTE hucresel agi icin kritik bir onem kazanmaktadir. Bu calismada LTE aglarinda remote-host ile PG-W arasinda calisan aktif kuyruk yonetim algoritmalari olan RED, CoDel, Pie ve pFIFO’nun performanslarinin, uctan uca ortalama verim, gecikme ve paket dusurme oranlari uzerindeki etkisi karsilastirmali olarak incelenmistir ve sonuclari degerlendirilmistir.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"285 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116104876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Meyve posalari icerdigi besin degerlerinden dolayi, gubre olarak kullaniminin yaninda hayvan yemi olarak da kullanimi cok yaygindir. Kusburnu, portakal, havuc, turp gibi bircok meyve sebze atiklari posa olarak degerlendirilmektedir. Calismada kapsaminda, kabin tip bir kurutucu ile 60, 65 ve 70 °C sicaklik degerlerinde kurutularak, armut posasinin ortalama kuruma sureleri, renk, asitlik (pH), suda cozunebilir kuru madde (SCKM) ve titrede edilebilir asitlik (T.A.) degerleri belirlenmistir. Urun, kurutma havasi sicakliklarinda yas baza (y.b.) gore % 10-13 nem seviyelerine kadar kurutulmustur. Sicaklik degerlerine gore ortalama kuruma sureleri sirasiyla; 24, 21 ve 12 saat olarak tespit edilmistir. Kurutma islemi esnasinda uzaklasan nem oranlari kurutma esitliklerinde islenerek egrileri olusturulmus ve en iyi tahmin eden modelin Midilli-Kucuk oldugu belirlenmistir. Kurutulan urunlere ait olculen renk degerleri tazeye gore kiyaslanarak istatistiki acidan en uygun kurutma havasi sicakligi belirlenmistir. Hesaplanarak belirlenen renk kriterlerinden olan, kroma degerleri tazeye gore kiyaslandiginda en uygun deger 65 °C kurutma sicakliginda belirlenmistir. Kurutulan urunlerin pomolojik ozellikleri hakkinda onemli bilgiler veren pH, SCKM, ve T.A. ozelliklerine ait en yuksek ve en dusuk ortalama degerler ise sirasiyla; 3.65-3.44, 2.70-2.33, 1.68-1.10 olarak belirlenmistir.
{"title":"Armut (Pirus communis L.) Posasının Bazı Kalite Değerleri Açısından Uygun Kurutma Sıcaklığının Belirlenmesi","authors":"Hakan Polatcı, Muhammed Taşova, Onur Saraçoğlu","doi":"10.21541/APJES.525655","DOIUrl":"https://doi.org/10.21541/APJES.525655","url":null,"abstract":"Meyve posalari icerdigi besin degerlerinden dolayi, gubre olarak kullaniminin yaninda hayvan yemi olarak da kullanimi cok yaygindir. Kusburnu, portakal, havuc, turp gibi bircok meyve sebze atiklari posa olarak degerlendirilmektedir. Calismada kapsaminda, kabin tip bir kurutucu ile 60, 65 ve 70 °C sicaklik degerlerinde kurutularak, armut posasinin ortalama kuruma sureleri, renk, asitlik (pH), suda cozunebilir kuru madde (SCKM) ve titrede edilebilir asitlik (T.A.) degerleri belirlenmistir. Urun, kurutma havasi sicakliklarinda yas baza (y.b.) gore % 10-13 nem seviyelerine kadar kurutulmustur. Sicaklik degerlerine gore ortalama kuruma sureleri sirasiyla; 24, 21 ve 12 saat olarak tespit edilmistir. Kurutma islemi esnasinda uzaklasan nem oranlari kurutma esitliklerinde islenerek egrileri olusturulmus ve en iyi tahmin eden modelin Midilli-Kucuk oldugu belirlenmistir. Kurutulan urunlere ait olculen renk degerleri tazeye gore kiyaslanarak istatistiki acidan en uygun kurutma havasi sicakligi belirlenmistir. Hesaplanarak belirlenen renk kriterlerinden olan, kroma degerleri tazeye gore kiyaslandiginda en uygun deger 65 °C kurutma sicakliginda belirlenmistir. Kurutulan urunlerin pomolojik ozellikleri hakkinda onemli bilgiler veren pH, SCKM, ve T.A. ozelliklerine ait en yuksek ve en dusuk ortalama degerler ise sirasiyla; 3.65-3.44, 2.70-2.33, 1.68-1.10 olarak belirlenmistir.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125128538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Medical decision-making has recently become a crucial research area due to its outputs related to the continuity of human life. Since the physicians used to employ statistical tools for a number of years, constructing a multi-attribute decision framework is quite difficult. In general, fuzzy decision aid systems provide flexibility to the physicians enabling them to express their opinions using linguistic variables. Moreover, orthopair fuzzy numbers allows the decision makers to represent their hesitations while providing linguistic data in both uncertain and hesitant environment. This paper proposes orthopair fuzzy TOPSIS (OFTOPSIS) methodology in order to rank the length of hospital stay of chronic obstructive pulmonary disease patients, who admitted to a chest diseases hospital with an acute exacerbation. The proposed method provides maximum flexibility to the physicians for expressing their hesitations to the system modelers, while assessing patients’ status according to pre-determined attributes. The novelty of this paper is to develop OFTOPSIS methodology, and conduct a case study in medical area to demonstrate the robustness of the proposed decision-making framework. The actual ranking and the ranking determined by OFTOPSIS method are compared by Spearman rank correlation coefficient to conclude whether there is a positive relationship between the ranking results.
{"title":"Ortoper Bulanık Kümelerle Bir Karar Verme Yaklaşımı: Ortoper Bulanık TOPSIS Metodu","authors":"Elif Doğu","doi":"10.21541/apjes.619339","DOIUrl":"https://doi.org/10.21541/apjes.619339","url":null,"abstract":"Medical decision-making has recently become a crucial research area due to its outputs related to the continuity of human life. Since the physicians used to employ statistical tools for a number of years, constructing a multi-attribute decision framework is quite difficult. In general, fuzzy decision aid systems provide flexibility to the physicians enabling them to express their opinions using linguistic variables. Moreover, orthopair fuzzy numbers allows the decision makers to represent their hesitations while providing linguistic data in both uncertain and hesitant environment. This paper proposes orthopair fuzzy TOPSIS (OFTOPSIS) methodology in order to rank the length of hospital stay of chronic obstructive pulmonary disease patients, who admitted to a chest diseases hospital with an acute exacerbation. The proposed method provides maximum flexibility to the physicians for expressing their hesitations to the system modelers, while assessing patients’ status according to pre-determined attributes. The novelty of this paper is to develop OFTOPSIS methodology, and conduct a case study in medical area to demonstrate the robustness of the proposed decision-making framework. The actual ranking and the ranking determined by OFTOPSIS method are compared by Spearman rank correlation coefficient to conclude whether there is a positive relationship between the ranking results.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122588443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Katırcıoğlu, Zafer Cingiz, Yusuf Çay, Ali Gürel, Suat Saridemi̇r, A. Kolip
Gunumuzde cesitli protokoller ile halojenik kloroflorokarbon (CFC) ve hidrokloroflorokarbon (HCFC) sogutucu akiskanlarinin ilerleyen zamanlarda kullanilmayacagi ve bu akiskanlara cesitli alternatiflerin olusturulmasi gerektigi gozlemlenmistir. Geleneksel sogutma etkinlik katsayisi (COP) hesaplama yonteminde, termodinamik ozellik tablolari ve basinc-entalpi diyagramlari kullanilmaktadir. Onerilen yontem sayesinde, COP hesaplanirken, bu tablo ve diyagramlarin kullanilmasina gerek duyulmayacaktir. Kizilotesi goruntuleme sistemi ile belirtilen bolgelerden goruntu alinmasi yeterli olacaktir. Bu calismada, R22 akiskanina alternatif olan, ozon tabakasina dost R417A ve R438A akiskanlarinin ticari sogutma sistemlerine yonelik performans analizi yapilmistir. CFC gazlarin tuketiminin yasaklanmasi ile birlikte gelinen surecte ozon tabakasina zarar veren diger bir gaz grubu olan HCFC gazlarin da kullanimi once sinirlandirilmis ardindan tamamen yasaklanmistir. Bu gazlardan en cok kullanilani R22 gazidir. Referans R22 gazi ile R438A ve R417A gazlarinin performanslari kizilotesi goruntu analizi ile gerceklestirmek icin bolgesel oz nitelik veri elde edinimi ile COP olmak uzere iki yontem onerilmistir. Ayrica gerceklestirilen iki ara yuz uzerinde, kizilotesi goruntulerden elde edilen buyuklukler, grafiksel ve sayisal olarak karsilastirilmaktadir. Elde edilen sayisal ve gorsel uygulama sonuclarina gore, R22 gazina en yakin performansi R438A gostermistir. Geleneksel hesaplamali performans testlerine gore, uygulanan sistemin kullanim kolayligi, uzaktan olcum ve es zamanli kayit alma noktasinda daha avantajli oldugunu gostermistir.
{"title":"R22 ve alternatifleri R438A ile R417A soğutucu akışkanları için kızılötesi görüntü işleme teknikleri kullanarak, soğutma sistem performansının incelenmesi","authors":"F. Katırcıoğlu, Zafer Cingiz, Yusuf Çay, Ali Gürel, Suat Saridemi̇r, A. Kolip","doi":"10.21541/apjes.726624","DOIUrl":"https://doi.org/10.21541/apjes.726624","url":null,"abstract":"Gunumuzde cesitli protokoller ile halojenik kloroflorokarbon (CFC) ve hidrokloroflorokarbon (HCFC) sogutucu akiskanlarinin ilerleyen zamanlarda kullanilmayacagi ve bu akiskanlara cesitli alternatiflerin olusturulmasi gerektigi gozlemlenmistir. Geleneksel sogutma etkinlik katsayisi (COP) hesaplama yonteminde, termodinamik ozellik tablolari ve basinc-entalpi diyagramlari kullanilmaktadir. Onerilen yontem sayesinde, COP hesaplanirken, bu tablo ve diyagramlarin kullanilmasina gerek duyulmayacaktir. Kizilotesi goruntuleme sistemi ile belirtilen bolgelerden goruntu alinmasi yeterli olacaktir. Bu calismada, R22 akiskanina alternatif olan, ozon tabakasina dost R417A ve R438A akiskanlarinin ticari sogutma sistemlerine yonelik performans analizi yapilmistir. CFC gazlarin tuketiminin yasaklanmasi ile birlikte gelinen surecte ozon tabakasina zarar veren diger bir gaz grubu olan HCFC gazlarin da kullanimi once sinirlandirilmis ardindan tamamen yasaklanmistir. Bu gazlardan en cok kullanilani R22 gazidir. Referans R22 gazi ile R438A ve R417A gazlarinin performanslari kizilotesi goruntu analizi ile gerceklestirmek icin bolgesel oz nitelik veri elde edinimi ile COP olmak uzere iki yontem onerilmistir. Ayrica gerceklestirilen iki ara yuz uzerinde, kizilotesi goruntulerden elde edilen buyuklukler, grafiksel ve sayisal olarak karsilastirilmaktadir. Elde edilen sayisal ve gorsel uygulama sonuclarina gore, R22 gazina en yakin performansi R438A gostermistir. Geleneksel hesaplamali performans testlerine gore, uygulanan sistemin kullanim kolayligi, uzaktan olcum ve es zamanli kayit alma noktasinda daha avantajli oldugunu gostermistir.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"275 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133104408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Betonarme Binaların Güçlendirilmesinde Uygun Merkezi Çelik Çapraz Yerleşiminin Belirlenmesi","authors":"E. Aydin, Elif Boru","doi":"10.21541/apjes.572750","DOIUrl":"https://doi.org/10.21541/apjes.572750","url":null,"abstract":"","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129472877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hibrit Laminer Akis Kontrolu (HLFC), sivil jet tasimaciligi ucaklarinin yakit tuketimini azaltmak icin havacilik endustrisindeki en onemli teknolojilerden biridir. Sinir tabaka emisinin neden oldugu surtunmeyi azaltmak icin ucak kanatlarinin ve kuyruk duzlemlerinin on kenarlarinda kucuk deliklere ihtiyac vardir. Bu kucuk deliklerin Ti-6Al-4V alasimlarina uygulanmasi icin cok fazla calismalar yapilmistir. Mikro lazer delme islemi uygulandiginda, delinmis deliklerin yakinligina bagli olarak bazi problemler ortaya cikmaktadir. Ek olarak, genis alanlara cok sayida delik acarken isil bozulmanin en aza indirilmesi daha da zorlasmaktadir. Bu arastirmanin amaci, mikro lazer delme isleminden kaynaklanan deformasyonu degerlendirmek ve en aza indirmek icin etkili bir dizi calismalar gelistirmektir. Bu calisma kapsaminda galvo tarayiciya sahip 50 W guc darbeli Ytterbium fiber lazer kullanilmistir. Her mikro delme islemi icin atilan lazerler arasi bekleme suresinin arttirilmasi, numunelerin her iki tarafinda agirlik kullaniminin ve delinmis numunelerin deformasyonu uzerine azot sogutmanin etkileri incelenmistir. Delme isleminden once ve sonra ornekler, entegre bir 3D lazer tarayicisina sahip 6 eksenli bir kol CMM ile taranmistir. PC-DMIS yazilimi kullanilarak deformasyon egrileri elde edilmistir. Sonuc olarak, bekleme suresi arttikca numunelerde daha az deformasyon gozlenmistir. Ek olarak, surece azot gazi eklenmesi deformasyon minimuma indirgeme cabalarini olumlu yonde etkilemistir.
混合层流控制(HLFC)是航空工业中减少民用喷气运输机燃料消耗的最重要技术之一。为了减少边界层吸力造成的阻力,需要在飞机机翼和尾翼的前缘开小孔。在 Ti-6Al-4V 合金上应用这些小孔方面已经做了大量工作。在使用微型激光钻孔时,由于钻孔距离较近,会产生一些问题。此外,在大面积钻大量孔时,最大限度地减少热变形变得更加困难。这项研究的目的是开发一套有效的程序,用于评估和尽量减少微型激光钻孔造成的变形。本研究使用了 50 W 脉冲镱光纤激光器和 Galvo 扫描仪。研究了增加每次微钻孔操作脉冲之间的停留时间、在样品两侧使用砝码和氮气冷却对钻孔样品变形的影响。在钻孔前后,使用集成了三维激光扫描仪的六轴臂坐标测量机对样品进行扫描。使用 PC-DMIS 软件获得了变形曲线。结果表明,随着停留时间的增加,试样的变形量减少。此外,在加工过程中加入氮气对尽量减少变形也有积极作用。
{"title":"An Investigation of the Deformation Patterns Due to the High-Speed Micro-Laser Drilling Process for Ti-6Al-4V Used in Aerospace Applications","authors":"A. Çelebi, H. Tosun, Ali Çağlar Önçağ","doi":"10.21541/apjes.576629","DOIUrl":"https://doi.org/10.21541/apjes.576629","url":null,"abstract":"Hibrit Laminer Akis Kontrolu (HLFC), sivil jet tasimaciligi ucaklarinin yakit tuketimini azaltmak icin havacilik endustrisindeki en onemli teknolojilerden biridir. Sinir tabaka emisinin neden oldugu surtunmeyi azaltmak icin ucak kanatlarinin ve kuyruk duzlemlerinin on kenarlarinda kucuk deliklere ihtiyac vardir. Bu kucuk deliklerin Ti-6Al-4V alasimlarina uygulanmasi icin cok fazla calismalar yapilmistir. Mikro lazer delme islemi uygulandiginda, delinmis deliklerin yakinligina bagli olarak bazi problemler ortaya cikmaktadir. Ek olarak, genis alanlara cok sayida delik acarken isil bozulmanin en aza indirilmesi daha da zorlasmaktadir. Bu arastirmanin amaci, mikro lazer delme isleminden kaynaklanan deformasyonu degerlendirmek ve en aza indirmek icin etkili bir dizi calismalar gelistirmektir. Bu calisma kapsaminda galvo tarayiciya sahip 50 W guc darbeli Ytterbium fiber lazer kullanilmistir. Her mikro delme islemi icin atilan lazerler arasi bekleme suresinin arttirilmasi, numunelerin her iki tarafinda agirlik kullaniminin ve delinmis numunelerin deformasyonu uzerine azot sogutmanin etkileri incelenmistir. Delme isleminden once ve sonra ornekler, entegre bir 3D lazer tarayicisina sahip 6 eksenli bir kol CMM ile taranmistir. PC-DMIS yazilimi kullanilarak deformasyon egrileri elde edilmistir. Sonuc olarak, bekleme suresi arttikca numunelerde daha az deformasyon gozlenmistir. Ek olarak, surece azot gazi eklenmesi deformasyon minimuma indirgeme cabalarini olumlu yonde etkilemistir.","PeriodicalId":294830,"journal":{"name":"Academic Platform Journal of Engineering and Science","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126479251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}