gazi university journal of science最新文献_第3页

A Low-Profile High Isolation Wideband Dual-Polarized Antenna for Sub-1 GHz Base Stations 用于 1 千兆赫以下基站的低矮型高隔离度宽带双极化天线

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gazi university journal of science Pub Date : 2023-07-24 DOI: 10.35378/gujs.1279556

E. A. Miran, M. Çiydem

引用次数: 0

Classical and Bayesian Inference for the Length Biased Weighted Lomax Distribution under Progressive Censoring Scheme 渐进式删减方案下长度偏差加权洛马克斯分布的经典推论和贝叶斯推论

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gazi university journal of science Pub Date : 2023-07-23 DOI: 10.35378/gujs.1249968

Amal S. HASSAN, Samah A. ATİA, Hiba Z. MUHAMMED

{"title":"Classical and Bayesian Inference for the Length Biased Weighted Lomax Distribution under Progressive Censoring Scheme","authors":"Amal S. HASSAN, Samah A. ATİA, Hiba Z. MUHAMMED","doi":"10.35378/gujs.1249968","DOIUrl":"https://doi.org/10.35378/gujs.1249968","url":null,"abstract":"In this study, the distribution’s reliability and hazard functions, as well as the population parameters, are estimated for the length biased weighted Lomax (LBWLo) based on progressively Type II censored samples. The maximum likelihood and Bayesian methods are implanted to get the proposed estimators. Gamma and Jeffery's priors serve as informative and non-informative priors, respectively, from which the posterior distribution of the LBWLo distribution is constructed. To obtain the Bayesian estimates, the Metropolis-Hasting (MH) algorithm is also used. We obtain asymptotic confidence intervals based on the Fisher information matrix. Using the sample produced by the MH method, we construct the intervals with the highest posterior densities. A numerical simulation research is done to evaluate the effectiveness of the approaches. Through Monte Carlo simulation, we compare the proposed estimators in terms of mean squared error. It is possible to get coverage probability and average interval lengths of 95% .The study's findings supported the idea that, in the majority of cases, Bayes estimates with an informative prior are more appropriate than other estimates.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"31 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139356327","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}

引用次数: 0

Optimal Equipment Capacity Planning in the Neonatal Intensive Care Unit with Simulation-Optimization Approach 利用仿真优化方法优化新生儿重症监护室的设备容量规划

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gazi university journal of science Pub Date : 2023-07-17 DOI: 10.35378/gujs.1247829

Mufide Narli, Yusuf Kuvvetli̇, Ali Kokangül

{"title":"Optimal Equipment Capacity Planning in the Neonatal Intensive Care Unit with Simulation-Optimization Approach","authors":"Mufide Narli, Yusuf Kuvvetli̇, Ali Kokangül","doi":"10.35378/gujs.1247829","DOIUrl":"https://doi.org/10.35378/gujs.1247829","url":null,"abstract":"Capacity planning should be performed to balance investment costs and benefits of investing to meet the current and future demand in intensive care units. Having a high capacity to increase patient admission will lead to unutilized capacity in some periods, thereby increasing costs. On the other hand, patient admission requests from inborn and transported patients might be rejected due to lack of equipment. It should be considered in terms of cost-effectiveness and patient health; therefore, optimal equipment capacity must be determined. In this study, the optimal capacity planning problem has been considered for the neonatal intensive care unit of a hospital adopting the simulation-optimization approach. A discrete event simulation model is proposed for a neonatal intensive care unit in Adana, Turkey. Then, the optimization model identified the optimal numbers of incubators, ventilators, and nitric oxide devices to maximize equipment efficiency and minimize total inborn patient rejection and transport ratios. Three different resource allocations are presented, and the best is obtained from these three objectives as 72 incubators, 35 ventilators, and three nitric oxide devices. The application results obtained have revealed that the rejection and transport rate, which is found to be 1.12% in the current situation, can be reduced to 0.2% with different numbers of equipment and that equipment efficiency can be achieved with optimal numbers of equipment. The results of the study can help the decision-makers when minimum transport and rejection ratios are critical which almost intensive care units are required. Furthermore, the proposed simulation-optimization model can be adapted to different neonatal intensive care units having the same characteristics.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":"54 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139358669","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}

引用次数: 0

OBSERVING CONDUCTANCE QUANTIZATION by a NOVEL MAGNETIC CONTROL SYSTEM 用一种新型磁控制系统观察电导量子化

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gazi university journal of science Pub Date : 2023-07-10 DOI: 10.35378/gujs.1222023

Dila Çi̇ğdem, Bilge Toprak Karakaya, Duru Deği̇mli̇, Meltem GÖNÜLOL ÇELİKOĞLU, Yavuz Öztürk

引用次数: 0

Survival Prediction with Extreme Learning Machine, Supervised Principal Components and Regularized Cox Models in High-Dimensional Survival Data by Simulation 基于极端学习机的高维生存数据生存预测、监督主成分和正则化Cox模型的仿真研究

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gazi university journal of science Pub Date : 2023-07-06 DOI: 10.35378/gujs.1223015

Fulden CANTAŞ TÜRKİŞ, İ. Kurt Omurlu, M. Türe

{"title":"Survival Prediction with Extreme Learning Machine, Supervised Principal Components and Regularized Cox Models in High-Dimensional Survival Data by Simulation","authors":"Fulden CANTAŞ TÜRKİŞ, İ. Kurt Omurlu, M. Türe","doi":"10.35378/gujs.1223015","DOIUrl":"https://doi.org/10.35378/gujs.1223015","url":null,"abstract":"Mortality risks of important diseases such as cancer can be estimated using gene profiles which are high-dimensional data obtained from gene expression sequences. However, it is impossible to analyze high-dimensional data with classical techniques due to multicollinearity, time-consuming processing load, and difficulty interpreting the results. For this purpose, extreme learning machine methods, which can solve regression and classification problems, have become one of the most preferred machine learning methods regarding fast data analysis and ease of application. The goal of this study is to compare estimation performance of risk score and short-term survival with survival extreme learning machine methods, L2-penalty Cox regression, and supervised principal components analysis in generated high-dimensional survival data. The survival models have been evaluated by Harrell’s concordance index, integrated Brier score, F1 score, kappa coefficient, the area under the curve, the area under precision-recall, accuracy, and Matthew’s correlation coefficient. All results showed that survival extreme learning machine methods that allow analyzing high-dimensional survival data without the necessity of dimension reduction perform very competitive with the other popular classical methods used in the study.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46047966","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}

引用次数: 0

Distinguishing Obstructive Sleep Apnea Using Electroencephalography Records 用脑电图记录鉴别阻塞性睡眠呼吸暂停

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gazi university journal of science Pub Date : 2023-07-04 DOI: 10.35378/gujs.1229166

I. Umut, Hakan Üstünel, Güven Çentik, E. Uçar, L. Öztürk

引用次数: 0

Efficient Algorithm for Dominatig Set In Graph Theory Based on Fundamental Cut-Set 基于基本割集的图论中控制集的有效算法

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gazi university journal of science Pub Date : 2023-07-03 DOI: 10.35378/gujs.1243008

Furkan Öztemiz, A. Karcı

{"title":"Efficient Algorithm for Dominatig Set In Graph Theory Based on Fundamental Cut-Set","authors":"Furkan Öztemiz, A. Karcı","doi":"10.35378/gujs.1243008","DOIUrl":"https://doi.org/10.35378/gujs.1243008","url":null,"abstract":"Determining the minimum dominating set in connected graphs is one of the most difficult problems defined as NP-hard. In this problem, it is aimed to determine the important nodes that can influence all nodes via the minimum number of nodes on the graph. In this study, an efficient near optimal algorithm showing a deterministic approach has been developed different from the approximation algorithms mentioned in literature for discovering dominating set. The algorithm has O(n3) time complexity in determining the Dominating Set (DS). At the same time, the algorithm is a original algorithm whose solution is not random by using fundamental cut-set. The DS algorithm consists of 3 basic phases. In the first phase of the algorithm, the algorithm that constructs the special spanning tree (Karci Max tree) of the graph is developed. In the second phase, the algorithm that finds the fundamental cut sets using the Kmax spanning tree is developed. In the last phase, Karci centrality node values are calculated with fundamental cut set and by using these Karci centrality node values, an algorithm has been developed to identify DS nodes. As a result of these three phases, the dominance values of the nodes on the graph and the DS nodes are calculated. The detected Karci centrality node values give priority to the node selection for determining the DS. All phases of the developed DS and Efficient node algorithms were coded in R programming language and the results were examined by running on sample graphs.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48515752","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}

引用次数: 0

Examining the Corrosion Behavior of The 6061-T6 Al Alloy Inside Seawater With Decorative Gold- And Silver-Color Coating 6061-T6铝合金在海水中金银装饰涂层腐蚀行为的研究

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gazi university journal of science Pub Date : 2023-07-01 DOI: 10.35378/gujs.1219180

J. Erkmen, Benek Hamamci, A. Aydin

引用次数: 0

Fine-Kinney-Based Occupational Risk Assessment using Pythagorean Fuzzy AHP-COPRAS for the Lifting Equipment in the Energy Distribution and Investment Sector 基于精细基尼的能源分配和投资领域起重设备的模糊层次分析法- copras职业风险评估

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gazi university journal of science Pub Date : 2023-06-05 DOI: 10.35378/gujs.1227756

Suleyman Recep Satici, Suleyman Mete

{"title":"Fine-Kinney-Based Occupational Risk Assessment using Pythagorean Fuzzy AHP-COPRAS for the Lifting Equipment in the Energy Distribution and Investment Sector","authors":"Suleyman Recep Satici, Suleyman Mete","doi":"10.35378/gujs.1227756","DOIUrl":"https://doi.org/10.35378/gujs.1227756","url":null,"abstract":"The initial risk assessment, especially when using a risk score system, is the main step in a risk assessment process that comes after determining the scope of the risks and assessment. The Fine-Kinney method, a thorough approach to quantitative assessments to help keep risks under control, is commonly used in risk assessment. A risk score (RS) is determined using the standard version of Fine-Kinney by mathematically multiplication of probability (P), exposure (E), and consequence (C) parameters. The Fine-Kinney-based risk evaluation approach has the disadvantage of not accounting for the relationships among the risk parameters' interaction and determining the risk precedence of work-related hazards. Hence, a new hazard evaluation method for occupational health and safety (OHS) is required to lessen the adverse effects of rising dangers. In this paper, a novel approach is proposed for integrating Fine–Kinney-based occupational hazard evaluation and AHP-COPRAS for the energy distribution and investment sector under the Pythagorean fuzzy environment. A lifting equipment case study is used to demonstrate practicality and efficacy of the suggested integrated approach. To verify the novel method to risk assessment, a comparative study and sensitivity analysis are also provided. As a result, using the benefit of Pythagorean fuzzy sets, which more effectively express uncertainty, the integrated approach yields more logical conclusions for assessing work-related hazards in the energy distribution and investment sector.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42866825","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}

引用次数: 1

A Two-Phase Approach for Reliability-Redundancy Optimization of a Communication Satellite 通信卫星可靠性冗余优化的两阶段方法

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gazi university journal of science Pub Date : 2023-05-24 DOI: 10.35378/gujs.1186561

Gazi University, T. Teti̇k, G. Das, B. Birgoren

{"title":"A Two-Phase Approach for Reliability-Redundancy Optimization of a Communication Satellite","authors":"Gazi University, T. Teti̇k, G. Das, B. Birgoren","doi":"10.35378/gujs.1186561","DOIUrl":"https://doi.org/10.35378/gujs.1186561","url":null,"abstract":"The development and launch of communication satellite projects pose significant challenges and costs. The expenses can range from several hundred million dollars, contingent on factors such as mission objectives, satellite system size and complexity including the launch vehicle, and ground infrastructure. Satellites must be designed to withstand harsh conditions in space, such as the extreme temperatures, radiation, and other hazards, while delivering reliable communication services to its users. However, once a satellite is launched, physical maintenance interventions become infeasible in the event of technical problems. Thus, reliability is a critical aspect for these expensive systems.\u0000\u0000This study aims to minimize the cost of a high-tech communication satellite by addressing design considerations that meet customer reliability requirements without exceeding power and redundant equipment limits. To achieve this goal, we propose an integer non-linear programming model in this research. To solve the satellite design problem, we adopt a two-stage solution approach. Conventional industrial practices in satellite design often involve iterative attempts to determine the redundancy level of onboard units based on customer reliability requirements. These processes rely heavily on the experience of design engineers who evaluate a limited number of alternatives to determine the number of redundant units, resulting in sub-optimal outcomes. In contrast, our proposed approach systematically handles the problem and yields optimal results. Our findings demonstrate that the proposed two-phase approach can achieve optimal redundancy levels within seconds.","PeriodicalId":12615,"journal":{"name":"gazi university journal of science","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43719902","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}

引用次数: 0