CLAIRAUT ANTI-INVARIANT SUBMERSIONS FROM COSYMPLECTIC MANIFOLDS

Tastan, Hakan Mete,Aydin, Sibel Gerdan The Honam Mathematical Society 2019 호남수학학술지 Vol.41 No.4

We investigate the new Clairaut conditions for anti-invariant submersions whose total manifolds are cosymplectic. In particular, we prove the fibers of a proper Clairaut Lagrangian submersion admitting horizontal Reeb vector field are one dimensional and classify such submersions. We also check the existence of the proper Clairaut anti-invariant submersions in the case of the Reeb vector field is vertical. Moreover, illustrative examples for both trivial and proper Clairaut anti-invariant submersions are given.

Evaluation of the Knowledge, Behavior and Health Beliefs of Individuals over 50 Regarding Colorectal Cancer Screening

Tastan, Sevinc,Andsoy, Isil Isik,Iyigun, Emine Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

The aim of the study was to evaluate of the knowledge, behavior and health beliefs of individuals over 50 regarding colorectal cancer screening, with a descriptive and cross-sectional design at Karabuk Life and Health Center in Turkey. A total of 160 people meeting set criteria were included in the study. The questionnaire consisted of two parts. The first part was composed of questions on characteristics of participants and the second part of questions derived from the Champion's Health Belief Model Scale. Only 15.0% of participants (n=24) had undergone a fecal occult blood test (FOBT), 11.3% (n=18) had had colonoscopy and 4.4% (n=7) had had sigmoidoscopy. Some 90.6% of the participants had low levels of risk awareness about the colorectal cancer. It was found that the average point of severity subscale of participants over 65 is higher than that of participants under 65 (p<0.05). In conclusion, because of the many barriers and health beliefs for the colorectal cancer screening program, the rate of participation in screening programs is not sufficient. Healthcare providers have important responsibilities for increasing rate of attendance in colorectal cancer screening programs.

Health Beliefs Concerning Breast Self-examination of Nurses in Turkey

Sevinc Tastan,Emine Iyigün,Ayse Kılıc,Vesile Unver 한국간호과학회 2011 Asian Nursing Research Vol.5 No.3

Purpose: The purpose of the study was to evaluate the health beliefs regarding breast self-examination (BSE) and their relationship with age, educational status and history of breast cancer in the family among nurses working in a university hospital. Methods: A cross-sectional design was used, with a convenience sample of 381 nurses at a military university hospital in Ankara in Turkey. Data were collected by using a personal data form and the Champion’s Health Belief Model Scale. Descriptive statistics, logistic regression, Mann-Whitney U test and Kruskal Wallis Test were conducted. Results: The proportion of nurses reported doing BSE regularly is 47.2%. Controlling variables such as age,body mass index, the age at first birth, breast cancer in the family history and educational background,we found that the subscales of the health belief model, BSE benefit (OR ¼ 0.782), self-efficacy (OR ¼ 0.919), and risk perception (OR ¼ 0.114) have statistically significant effects on the risk of not making BSE. Conclusion: It is important to be aware of the health beliefs of nurses regarding BSE so that their own health can be protected and improved. Beneficial attitudes and behaviors of nurses regarding BSE will enable them to provide more effective services to women regarding breast cancer. Understanding the nurses’ health beliefs, attitude and behavior that are influential to make BSE will guide nursing practices towards early diagnosis of breast cancer at the societal level.

Business Cycle Asymmetries in Turkey: An Application of Markov-Switching Autoregressions

Huseyin Tastan 한국국제경제학회 2008 International Economic Journal Vol.22 No.3

This paper examines business cycle characteristics of Turkish economy in the liberalization pe- riod (post-1980 period) using a Markov-switching Autoregressive (MSAR) model framework. The importance of model selection process is emphasized in an extensive search for the appropriate MS model. The business cycle properties are found to be very sensitive to the state dimension, the choice of the MS model (classi¯ed according to regime-dependent parameters) and the autoregres- sive lag order. The chosen two-regime MS model suggests four recessionary and ¯ve expansionary phases in the post-1980 period. Business cycle phases are found to be asymmetric with probability of switching from a recession to expansion exceeding the probability of switching from expansion to recession. The paper also provides evidence on the usefulness of a non-linear model as compared to linear alternative in the context of business cycle research in an emerging economy using various parametric and nonparametric tests. Nonlinear and linear models are compared and evaluated using kernel density and conditional expectation estimates by simulating data from respective models.

Internet of Things based Smart Energy Management for Smart Home

( Mehmet Tastan ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.6

Thanks to internet, as one of indispensable parts of our lives, many devices that we use in our daily lives like TV, air conditioner, refrigerator, washing machine, can be monitored and controlled remotely by becoming more intelligent via Internet of Things (IoT) technology. Smart Home applications as one of the elements of smart cities, are individually the most demanded application without question. In this study, Smart Energy Management (SEM) system, based on NodeMCU and Android, has been designed for SEM, which is a part of the smart home application. With this system, household energy consumption can be monitored in real time, as well as having the ability to record the data comprising of operation times and energy consumption information for each device. Additionally, it is ensured to meet the energy needs on a maximized level possible, during the hours when the energy costs are lower owing to the SEM system. The Android interface provides the users with the opportunity to monitor and change their electricity consumption habits in order to optimize the energy efficiency, along with the opportunity to draw up of a daily and weekly schedule.

Clairaut anti-invariant submersions from cosymplectic manifolds

Hakan Mete Tastan,Sibel Gerdan Aydin 호남수학회 2019 호남수학학술지 Vol.41 No.4

We investigate the new Clairaut conditions for anti-invariant submersions whose total manifolds are cosymplectic. In particular, we prove the fibers of a proper Clairaut Lagrangian submersion admitting horizontal Reeb vector field are one dimensional and classify such submersions. We also check the existence of the proper Clairaut anti-invariant submersions in the case of the Reeb vector field is vertical. Moreover, illustrative examples for both trivial and proper Clairaut anti-invariant submersions are given.

On spirallike functions related to bounded radius rotation

Asena Cetinkaya,Hakan Mete Tastan 호남수학회 2022 호남수학학술지 Vol.44 No.1

In the present paper, we prove the growth and distortion theorems for the spirallike functions class $\mathcal{S}_k(\lambda)$ related to boundary radius rotation, and by using the distortion result, we get an estimate for the Gaussian curvature of a minimal surface lifted by a harmonic function whose analytic part belongs to the class $\mathcal{S}_k(\lambda)$. Moreover, we determine and draw the minimal surface corresponding to the harmonic Koebe function.

Identifying Women's Knowledge about Risk Factors of Breast Cancer and Reasons for Having Mammography

Guvenc, Inanc,Guvenc, Gulten,Tastan, Sevinc,Akyuz, Aygul Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

The aim of this study was to identify breast cancer risk factors and reasons for having mammography of the women who applied for mammography, as well as to determine their level of knowledge about risk factors and level of risk perception, and anxiety concerning breast cancer. This cross-sectional descriptive study was conducted from June 15, 2010 through September 10, 2010, in a university hospital in Ankara, Turkey. A questionnaire prepared by the researchers was used to collect the data. The mean age of the women was $52.1{\pm}9.98$ years. Sixteen percent of the women had a family history of breast cancer. The majority of participants had mammograms (75.8%) before and had gained knowledge about breast cancer and its screening (73.7%). The leading source of information about breast cancer was physicians (46.2%). Physician recommendations, having breast-related complaints, and family history of breast cancer were important reasons to obtain mammography. The mean knowledge score about risk factors of breast cancer was $4.15{\pm}2.73$ and the mean anxiety score was $1.65{\pm}1.61$. It was found that some socio-demographic and obstetrical characteristics of women, their family history, and risk perceptions about breast cancer affect their knowledge and anxiety scores about breast cancer. In conclusion, the present study identified a number of factors affecting mammography participation for women. The results of this study can be helpful in promoting screening for breast cancer.