62 research outputs found
Corresponding Author: Tolga DEMİRCAN
No full textGünümüzde içten yanmalı motorlar otomotiv, denizcilik, havacılık vb. birçok sektörde çok yaygın olarak kullanılmaktadır. Tek silindirli ve küçük boyutlarda yapılabileceği gibi, özellikle gemilerde kullanılmak üzere çok büyük boyutlarda da üretilebilmektedir. İçten yanmalı motorlar, birden çok parçanın birleşmesi ile oluşan kompleks yapılardır. Ayrıca silindir içerisinde gerçekleşen yanma olayı da oldukça hızlı ve karmaşık bir reaksiyondur. Dolayısıyla bir motorun güç performansı birden çok faktöre bağlıdır. Bu faktörlerden en önemlilerinden biri de yanmanın, ideal yanmaya yakın koşullarda sağlanabilmesidir. Bu ise, silindir içerisinde reaksiyona giren oksijen ve yakıtın uygun oranlarda karışması ile mümkün olabilmektedir. Bir motorun sürekli yüksek performansta çalışabilmesi için, yakıtın sürekli olarak, hava ile yeterli oranda beslenmesi gerekmektedir. Bu hava beslemesi emme manifoldu aracılığı ile gerçekleşir. Dolayısıyla iyi bir yanmanın sağlanabilmesi için emme manifold tasarımı önemli bir rol oynamaktadır. Bu amaçla, bu çalışmada; bir dizel motorda emme havasının ihtiyaç duyulan miktarda sağlanabilmesi için, emme manifoldunun giriş açılarının etkileri ele alınmıştır. Farklı giriş açıları için Ansys Fluent paket programı aracılığı ile simülasyonlar yapılmış ve akış karakteristiklerine olan etkileri irdelenmiştir. Simülasyonlardan elde edilen sonuçlar ışığında, manifold içerisindeki hız ve basınç dağılımları elde edilmiş ve çıkış debi değerleri aracılığıyla optimum şartlar belirlenmiştir.Today, internal combustion engines are widely used in many sectors such as automotive, marine, aviation, etc. They can be produced in single cylinders and small sizes for the automotive sector as well as in very large sizes for use on ships. Internal combustion engines are complex structures formed by joining multiple parts. In addition, the combustion inside the cylinder is a very quick and complicated reaction. Therefore, the power performance of the motor depends on multiple factors. One of the most important of these factors is approaching burning to ideal burning conditions. This is possible by mixing oxygen and fuel in the cylinder in a suitable ratio. For an engine to work at a high performance constantly, the fuel must be supplied continuously with sufficient air. The intake manifold is used for this air supply. Therefore, intake manifold design plays an important role for good combustion. For this purpose, in this study, the effects of the inlet angles of the intake manifold are discussed so that a sufficient amount of intake air can be supplied to a diesel engine. With the help of the Ansys Fluent package program, simulations were made for different manifold inlet angles and the effects of the inlet angles on flow characteristics were discussed. In the light of the results obtained from the simulations, velocity and pressure distributions in the manifold were obtained and optimum conditions were determined by outlet flow rate
Implications of cyber weapons in cybersecurity : a case study of Stuxnet and Duqu
No full textBu çalışma devlet temelli siber silahlar olan Stuxnet ve Duqu'nun etkilerini ve yeteneklerini literatürün belirlediği siber silah tanımlarıyla karşılaştırarak siber güvenlik ve bilgisayar ağı operasyonlarına olan etkilerini incelemeyi ve tartışmayı amaçlamaktadır. İlk siber savaş olarak nitelendirilen, Estonya devletine karşı 2007 yılında gerçekleştirilen dağıtık hizmet engeli saldırıları da siber silah olarak sınıflandırıp sınıflandırılamayacağını anlamak amacıyla incelenmiştir. Çalışma Stuxnet'in siber silah tanımlarına uyduğunu saptarken, iki devlet temelli zararlı yazılım arasındaki operasyonel farklılıklar nedeniyle Duqu yalnızca bir casusluk aracı olarak nitelendirilmiştir. Estonya'ya karşı yapılan hizmet engelleme saldırılarının ise literatürde ortaya konan siber silah ya da siber savaş kavramlarına uymadığı saptanmıştır
urinary incontinence by demircan_özmen et al
No full texturinary incontinence, survey, questionnaires; iciq-sf, wagner's quality of life questionnaire applied in a study population recruited in Zonguldak City-Region of Western Black Sea Costal Rim of Turke
Comparison of PV Power Production Estimation Methods Under Non-homogeneous Temperature Distribution for CPVT Systems
No full textThe way to increase energy generation in a standard photovoltaic (PV) or photovoltaic/thermal (PV/T) system is the tracking of the sun and/or concentrating to increase the solar energy coming into the field. As the radiation is increased in both concentrated PV and PV/T systems, both PV power output and PV module temperature increase. The fact that the PV module temperature increases and exceeds the reasonable level reduces the life of solar cells and permanently damages the cells. The way to prevent this is to cool the PV modules. In other words, thermal energy is absorbed by integrating the thermal system. Thus, both electrical and thermal energy needs will be met easily, and a concentrating photovoltaic thermal (CPVT) system produces both electricity and thermal energy from the sun. Electrical and thermal behavior analyzes of CPVT systems are important issues in order to robust and accurate deciding for electrical and thermal power production. In a previous study, finite volume methods were applied for thermal analysis of the CPVT system. Temperature distribution of the PV modules and CPVT surfaces was done. In the numerical analysis; power/temperature coefficient-based method was used for electrical power estimation. In this chapter, power/temperature coefficient-based and five parameter models of PV modules were presented and discussed for forecasting of electrical power production. Decided to PV module temperature in power/temperature coefficient model and temperature distribution applications on diode model were discussed. Power/temperature-based power estimation methods are depending on first, medium, and end PV module temperature. However, different case studies for CPVT electrical power production forecasting methods were investigated. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd
Sağlık Çalışanlarının Yeme Davranışlarının Hollanda Yeme Davranışı Anketi (DEBQ) ile Değerlendirilmesi
No full textAmaç: Bu çalışmada, Zonguldak Bülent Ecevit Üniversitesi (ZBEÜN) Sağlık Uygulama ve Araştırma Hastanesinde çalışan doktor ve hemşirelerin obezite sıklığı ile yeme tutum ve davranışlarının incelenmesi ve birbirleri arasındaki ilişkilerin değerlendirilmesi amaçlanmıştır. Gereç ve Yöntemler: Bu araştırma, 260 sağlık çalışanı üzerinde gerçekleştirilen kesitsel ve tanımlayıcı tipte bir çalışmadır. Araştırmada veri toplama aracı olarak sosyodemografik veri formu ve Hollanda Yeme Davranışı Anketi (DEBQ) kullanılmıştır. Elde edilen veriler SPSS 20 Programı kullanılarak değerlendirilmiştir. Bulgular: Doktor ve hemşirelerin obezite sıklığı %9,2 olarak saptanmıştır. Obez bireylerin %62,5’inde kronik hastalık olduğu ve %83,3’ünün daha önce zayıflama diyeti yaptığı gözlenmiştir. Katılımcılardan diyet öyküsü olanların duygusal yeme, kısıtlayıcı yeme ve dışsal yeme faktörlerinin ortalaması daha yüksek saptanmıştır. Duygusal yeme davranışı ile Beden kitle indeksi (BKİ) sınıflaması arasında anlamlı bir fark bulunmuştur. Duygusal yeme puanları yüksek olanlarda kısıtlayıcı ve dışsal yeme puanlarının da yüksek olduğu görülmüştür. Sonuç: Obez olan sağlık çalışanlarının kronik hastalık varlığının daha yüksek olduğu, yetersiz ve dengesiz beslenmenin sağlığı olumsuz yönde etkilediği görülmüştür. Hastalarına ve içinde yaşadıkları topluma rol model olan sağlık çalışanlarına; kendi sağlıklarını korumak ve geliştirmek, sağlıklı yaşam biçimini benimsemeleri ve davranış haline getirebilmeleri için öğrencilik dönemindeki eğitimlerin zorunlu hale getirilmesi, hizmet içi eğitimlerin yapılması ve bu eğitimlerin devamlılığı sağlanabilir.</jats:p
Independence or Development?: An Overview of TurkeyÃs Foreign Language Education Policies
No full textMany countries have long had two sorts of interests; on the one hand, they have had to remain independent via protecting and promoting their official languages as a powerful symbol of their identities, and on the other hand, they have had to enable technological and economic development, which essentially involves international communication, usually by means of a foreign language. These two sorts of interests have often posed a dilemma for those countries and their peoples, because protecting and promoting identities have often implied closed and egocentric policies while international communication has involved more open and other-conscious policies. In todayÃs world, this dilemma is even more highlighted because of the so-called "globalization", which is taking place. In this article, I will present this dilemma by focussing on one country, Turkey, and its foreign language education policies. An historical account of the countryÃs interaction with other languages (than Turkish) will precede a presentation of the recent shape the recurring dilemma took, namely, teaching foreign languages versus teaching in a foreign language, in the daily national papers and publications in the1989 and 1997 discussions. I will then make personal suggestions of conduct for decision-makers in Turkey and other countries facing the same dilemma.Turkey, foreign language education, language planning
Tanzimat'tan Cumhuriyet'e aydınlık bir yüz : Abdülhak Hâmit Tarhan
No full textCataloged from PDF version of article.Abdülhak Hamit Tarhan (1852-1937) is the author of a large and
comprehensive volume of works is one of the most prolific authors in Turkish
Literature whose works range from poetry to drama. It can be easily deducted
through a rough analysis concerning his works that the poet/author had endorsed the
works published within the framework of "project of civilization" and pro-reformist
movements which occurred along the period beginning from Tanzimat Era
(Administrative Reforms in 1839) including İstibdat Era (Oppression) and
Meşrutiyet Era (Constitutional Monarchy) till the Proclamation of Republic in 1923.
There is also a general agreement among the pundits of literature and scholars who
carried out researches regarding Abdülhak Hâmit Tarhan that he scrutinized the
"female problematic" in his drams and poems. Although Gündüz Akıncı strongly
argued that "Abdülhak Hâmit Tarhan is the first feminist author in Turkish
Literature", it is remarkable that no research has been carried out regarding this
aspect of the author so far. Within the framework of this study, Abdülhak Hâmit
Tarhan's perspective of female problematic, his propositions concerning the solutions
and his contributions to the Ottoman-Turkish Feminist Movement has been argued
by means of analyzing his drama works, memories and lettersDemircan, Aynu
Evaluation of Respiratory Symptoms in Workers of a Rubber Factory
No full textAim: In this study, our objective was to investigate whether there is any relationship between working in the rubber industry and having respiratory symptoms. Method: This study was performed on 141 workers of a rubber factory. Anamnesis, physical examination and pulmonary function tests (PFT) were evaluated. Peak Expiratory Flow (PEF) follow-up and skin Prick Test were administered to the patients according to the results of respiratory system complaints, physical examination and PFT. Result: One hundred and forty one workers who accepted to participate in the study consisted of 116 (82.3%) males and 25 females (17.7%). In the comparison group with greater exposure results were obtained in the normal range, however the parameters of FEV 1 /FVC and FEF 25-75 (%) were lower in the greater exposure group. This difference was statistically significant (p<0.05). Variability was greater than 20% in 9 (6.3%) workers in the evaluation of PEF-meter follow-up forms. Conclusion: In conclusion, our study has demonstrated that exposure to dust and smoking in rubber industry seem to be associated with the development of occupational respiratory symptoms and diseases. That’s why, control of dust exposure and cessation of smoking is important in prevention of this situations
Kömür Madeni İşçilerinde Plazma Antikoagülan Protein Düzeyleri ve Trombin Zamanının Değerlendirilmesi
No full textORIGINAL ARTICLE - EVALUATION OF ERYTHROCYTE Na+, K+ -ATPASE AND SUPEROXIDE DISMUTASE ACTIVITIES AND MALONDIALDEHYDE LEVEL ALTERATION IN COAL MINERS
No full textThe purpose of the present study was to determine the structural
integrity of red blood cells in coal miners by assessing the
concentration of malondialdehyde and the activities of superoxide
dismutase and, Na+, K+ -ATPase in erythrocytes. Occupational exposure
to coal mine dust can result in a wide range of lung diseases, which
include pneumoconiosis, bronchitis, and emphysema. Pathophysiological
mechanisms of the diseases are not fully understood; however,
cytotoxicity is related to reactive oxygen substances which are
produced by coal dust. The study population consisted of 40 coal
workers previously known not to have any pulmonary disease and 34
healthy subjects who were randomly selected from the population
register or recruited from the hospital staff. The activities of Na+,
K+ -ATPase in the erythrocyte membrane was significantly decreased in
the coal workers as compared to the control group. Serum potassium and
iron concentrations were significantly higher whereas serum sodium was
moderately decreased in coal workers as compared to control. MDA levels
of all samples were significantly increased in the coal workers as
compared to the control group. SOD activity in serum and erythrocyte
was significantly lower in the coal miner group as compared to the
control group. The present study demostrated that the elevated MDA and
iron levels and insufficiency of antioxidant potential in serum and
erythrocytes cause a decrease in erythrocyte Na+, K+ -ATPase enzyme
activity in coal miners as compared to normal subjects
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