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A phenomenological research on project managers' perceptions of project failure
No full textLisansüstü Eğitim Enstitüsü, Ekonomik ve Sosyal Etki Değerlendirme Çalışmaları Ana Bilim DalıGiderek zorlaşan rekabet koşulları, başarılı değişim programlarının temel araçlarından biri olan projelerin sayısını ve önemini artırmaktadır. Bununla ilişkili olarak projelerin etkili yönetimi ve buna ilişkin metodoloji ile standartlar ilgi görmektedir. Organizasyonlar projeler aracılığıyla arzu edilen hedeflere ulaşmayı denemektedir; bununla birlikte proje başarısızlığı yaygın bir fenomendir. Tamamen veya kısmen başarısızlıkla sonuçlanan projelerin organizasyonlara getirdiği mali yükün yüksek olduğu bilinmektedir. Bu araştırmanın amacı, proje yöneticilerinin projelerin başarısızlığına yönelik algılarını ve başarısızlık deneyimlerini incelemek, yaşanmış deneyimlerin ortak anlamını keşfetmektir. Bu doğrultuda nitel araştırma desenlerinden fenomenoloji kullanılmıştır. Araştırmanın amacına uygun olarak yirmi proje yöneticisi çalışma grubunu oluşturmuş; katılımcılarla derinlemesine görüşmeler gerçekleştirilerek veri toplanmıştır. Veriler fenomenolojik analiz kullanılarak çözümlenmiştir. Bulgulara göre projelerin başarısında iletişim/koordinasyon yönetimi, risk ve belirsizlik yönetimi, bütçe ve maliyet yönetimi ve hedeflere ulaşma ön plandayken, proje başarısızlıklarında zaman yönetimi ve planlamada yaşanan sıkıntılara bağlı temalar öne çıkmaktadır. Çalışmada ortaya konan temalar literatür ışığında tartışılmış, başarısızlık deneyimine ilişkin bireysel farklılıkların tespitiyle bu fenomen betimlenmiştir.The number and significance of projects as one of the key tools of effective change programmes have increased in response to increasingly challenging competitive conditions. In this regard, effective project management, as well as related methodologies and standards, are gaining popularity. Organizations strive to attain their goals through the delivery of projects; nevertheless, the occurrence of project failure is a prevalent phenomenon. The financial implications for organizations are substantial when projects meet complete or partial failure. The purpose of this study is to examine the perceptions and experiences of project managers towards the failure of projects and to discover the shared meaning of lived experiences. Phenomenology, a qualitative research design, was employed in this study. The study group consisted of twenty project managers, selected in accordance with the study's objectives. Data collection was carried out through in-depth interviews conducted with the participants. The data is examined using phenomenological analysis. Based on the research findings, it has been observed that effective project management is essential for achieving success in various aspects such as communication and coordination management, risk and uncertainty management, budget and cost management, and goal attainment. Conversely, project failures often stem from issues related to time management and deficiencies in the planning process. The study's findings were analyzed in relation to existing literature, and the phenomenon was elucidated by examining individual variations associated with the experience of failure
Comparison of a Dynamic Model of Electric Arc Furnace with Actual Operation Data for Voltage Flicker Analysis in Electrical Power Network
No full textElectric arc furnaces (EAFs) used in the iron and steel manufacturing industry for melting and re?ning scrap metals are one of the most disturbing loads that exhibit unbalanced and highly nonlinear characteristics. Serious voltage fluctuations occur in the power system as a result of the rapid change in the current drawn from the grid by the EAF. Voltage fluctuations lead to a power quality problem known as flicker, which is defined as observable changes in light sources that affect the production environment, cause eye fatigue in personnel, and lower the work concentration levels. To investigate the voltage flicker problem, an accurate mathematical model describing the behavior of the EAF load is required. In this study, a dynamic EAF model that can be adjusted to different operating conditions has been developed in the time domain. The electric arc voltage has been modeled as an externally controllable voltage source. The instantaneous arc voltage has been expressed as a function of the arc length independent of the current. The arc resistance, which varies with time and is nonlinear, has also been calculated with differential equations using the instantaneous arc voltage value. To measure the short-term flicker severity index caused by the EAF in the power system, a flicker meter in compliance with the International Electrotechnical Commission (IEC) 61000-4-15 standard has been designed. The current-voltage characteristics of the EAF, its effect on the power system, and the flicker severity occurring at the point of common coupling (PCC) have been analyzed with simulation studies using the PSCAD/EMTDC software. Besides, the simulation results of the dynamic model of the EAF have been compared with the results obtained from the model based on the measured ?eld data
Immune cell-specific and common molecular signatures in rheumatoid arthritis through molecular network approaches
No full textRheumatoid arthritis (RA) is an autoimmune disorder and common symptom of RA is chronic synovial inflammation. The pathogenesis of RA is not fully understood. Therefore, we aimed to identify underlying common and distinct molecular signatures and pathways among ten types of tissue and cells obtained from patients with RA. In this study, transcriptomic data including synovial tissues, macrophages, blood, T cells, CD4+T cells, CD8+T cells, natural killer T (NKT), cells natural killer (NK) cells, neutrophils, and monocyte cells were analyzed with an integrative and comparative network biology perspective. Each dataset yielded a list of differentially expressed genes as well as a reconstruction of the tissue-specific protein-protein interaction (PPI) network. Molecular signatures were identified by a statistical test using the hypergeometric probability density function by employing the interactions of transcriptional regulators and PPI. Reporter metabolites of each dataset were determined by using genome-scale metabolic networks. It was defined as the common hub proteins, novel molecular signatures, and metabolites in two or more tissue types while immune cell-specific molecular signatures were identified, too. Importantly, miR-155-5p is found as a common miRNA in all tissues. Moreover, NCOA3, PRKDC and miR-3160 might be novel molecular signatures for RA. Our results establish a novel approach for identifying immune cell-specific molecular signatures of RA and provide insights into the role of common tissue-specific genes, miRNAs, TFs, receptors, and reporter metabolites. Experimental research should be used to validate the corresponding genes, miRNAs, and metabolites.Adana Alparslan Turkes Science and Technology University Scientific Research Projects Committee (BAPKO) [19103010]; YOK 100/2000 Doctoral Fellowship ProgramThis research was supported by grants from Adana Alparslan Turkes Science and Technology University Scientific Research Projects Committee (BAPKO) in the context of project 19103010. The scholarships under the YOK 100/2000 Doctoral Fellowship Program provided to BC are greatly acknowledged
Tracing 2D Growth of Pancreatic Tumoroids Using the Combination of Image Processing Techniques and Mini-Opto Tomography Imaging System
No full textObjectives: In this study, we aimed to trace the 2D growth development of tumoroids produced with MIA PaCa-2 pancreatic cancer cells at different time points. Methods We cultured 3 different tumoroids with 0.5%, 0.8%, and 1.5% agarose concentrations and calculated the growth rate of the tumoroids with their images acquired at 9 imaging time points by mini-Opto tomography imaging system applying image processing techniques. We used the metrics contrast-to-noise ratio (CNR), peak signal-to-noise ratio (PSNR), and mean squared error (MSE) to analyze the distinguishability of the tumoroid structure from its surroundings, quantitatively. Additionally, we calculated the increase of the radius, the perimeter, and the area of 3 tumoroids over a time period. Results In the quantitative assessment, the bilateral and Gaussian filters gave the highest CNR values (ie, Gaussian filter: at each of 9 imaging time points in range of 1.715 to 15.142 for image set-1). The median filter gave the highest values in PSNR in the range of 43.108 to 47.904 for image set-2 and gave the lowest values in MSE in the range of 0.604 to 2.599 for image set-3. The areas of tumoroids with 0.5%, 0.8%, and 1.5% agarose concentrations were 1.014 mm(2), 1.047 mm(2), and 0.530 mm(2) in the imaging time point-1 and 33.535 mm(2), 4.538 mm(2), and 2.017 mm(2) in the imaging time point-9. The tumoroids with 0.5%, 0.8%, and 1.5% agarose concentrations grew up to times of 33.07, 4.33, and 3.80 in area size over this period, respectively. Conclusions The growth rate and the widest borders of the different tumoroids in a time interval could be detected automatically and successfully. This study that combines the image processing techniques with mini-Opto tomography imaging system ensured significant results in observing the tumoroid's growth rate and enlarging border over time, which is very critical to provide an emerging methodology in vitro cancer studies
Impact of titania phase structure and surface reactivity on the photocatalytic degradation of various dyes and textile wastewater
No full textTitania (TiO2) powders have been prepared by precipitation method in different precipitation media which contain sulfate, nitrate or organic species. Photocatalytic degradation of different dyes and a real textile wastewater have been conducted with these powders along with commercial powder Degussa P25 for comparison. Ethyl alcohol (organic medium), sulfuric acid (sulfate medium) and nitric acid (nitrate medium) have been used to dissolve titanium precursor for the precipitation of TiO2 in ammonia solution. UV-Vis DRS and XPS results indicate that S doping in sulfate medium precipitated powder and N doping in nitrate medium precipitated powder has been occurred and the presence of S or N containing impurities on the grain boundaries have been improved light absorption of TiO2 significantly. However, these powders have exhibited low surface reactivities. The highest surface reactivity has been obtained with the powder precipitated in organic medium which also has the highest crystallite sizes (76 nm rutile and 34 nm anatase crystallites) with relatively low rutile weight percentage (10.0%). The surface-normalized rate constants of this powder are 0.02038 min-1.m-2 in real textile wastewater degradation and 0.0161 min-1.m-2 in methyl orange degradation, which are 0.01563 and 0.0091 min-1.m-2, respectively, for Degussa P25. Results have shown that this powder show 30-70% higher surface reactivities compared to Degussa P25. The main structural difference of organic medium precipitated powder and Degussa P25 has been found to be the anatase-rutile weight ratio and crystallite size of rutile phase whereas band gap energy of Degussa P25 is lower and other properties are not significantly different.Scientific and Technological Research Council of Turkey (TUBITAK) [110M739]Acknowledgements This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with the grant number of 110M739
Active fault-tolerant control of quadrotor UAVs with nonlinear observer-based sliding mode control validated through hardware in the loop experiments
No full textMultirotor unmanned aerial vehicles (UAV) are highly prone to motor faults, which can arise from defective motors or damaged propellers. Motor faults severely change the multirotor UAV's dynamics and therefore endanger flight safety and reliability since the controller loses its efficiency. To cope with such crucial problems, a fault-tolerant controller is proposed in this paper for full control of a quadrotor UAV with motor faults. The proposed fault-tolerant approach consists of the nonlinear observer technique and the Sliding Mode Control (SMC). The designed novel nonlinear observer predicts the effects of motor faults on quadrotor dynamics and it is augmented with an SMC to create a fault-tolerant controller. In addition, the nonlinear observer enhances the robustness of the SMC against the uncertainties and disturbances acting on the quadrotor during flight. Any actuator fault will be treated as a disturbance detected by the nonlinear observer and will be attenuated directly by the proposed SMC. The disturbance attenuation capability achieved by the nonlinear observer decreases the amount of control action expected from the SMC, which results in advanced robustness without sacrificing the nominal control performance. The performance of the proposed nonlinear observer SMC (NOSMC) is demonstrated through simulations and testbed experiments. The results show that the proposed fault-tolerant controller effectively recovers the full control of the quadrotor with motor faults up to 40% while tracking the predefined trajectory and rotation angles as desired.Scientific and Technological Re-search Council of Turkey (TUBITAK) [120M793]This research is supported by the Scientific and Technological Re-search Council of Turkey (TUBITAK) under 3501 program, with project number [120M793]
Estimation of DC Motor Parameters Using Least Square-based Optimization Algorithm
No full text2023 Innovations in Intelligent Systems and Applications Conference, ASYU 2023 -- 11 October 2023 through 13 October 2023 -- Sivas -- 194153In daily life, Direct Current (DC) motors are employed in virtually all applications due to their ease of operation, simple construction, and affordability. Therefore, a proper mathematical model for DC motors is essential for developing model-based controllers and predicting system responses. In this paper, the Least Square-based Autoregressive-eXogenous (LS-ARX) optimization algorithm has been developed to estimate unknown parameters of the DC motor model. Furthermore, the unknown parameters of the motor have been estimated by using the Nonlinear Least Square (NLS) and Pattern Search (PS) methods from the MATLAB optimization toolbox. For the purpose of estimating the DC motor parameters, an experimental setup has been constructed to measure the angular velocity of the motor utilizing an Arduino and two different sensors (photon interrupter and hall-effect sensors). To transfer data from the Arduino program to the MATLAB environment, a serial connection has been established between the Arduino and the Python program. Utilizing the proposed algorithm and the MATLAB optimization toolbox, the accuracy of the estimation process has been evaluated and compared through coefficient of determination. As a result of the comparison, it can be observed that the LS-ARX optimization algorithm is extremely robust, and the unknown parameters of the DC motor have been estimated with a high degree of accuracy. © 2023 IEEE.Adana Alparslan Türkeş Bilim ve Teknoloji Üniversitesi, ATÜ, (21303004
The effect of social assistance on the political preferences of urban house women: The case of Adana
No full textLisansüstü Eğitim Enstitüsü, Kent Çalışmaları Ana Bilim DalıBu araştırmanın amacı sosyal yardımların Adana ilinde ikamet eden ev kadınlarının oy verme davranışları üzerindeki etkisini tespit etmeye yöneliktir. Araştırmada nitel araştırma yöntemlerinden içerik analizi kullanılmıştır. Araştırma evrenini sosyal yardımlardan yararlanan ve yararlanmayan şehirli ev kadınları oluşturmaktadır. Çalışma grubu ise Adana ili, Seyhan, Çukurova, Yüreğir ve Sarıçam ilçelerinde ikamet eden, sosyal yardımlardan faydalanan 15 kadın ve sosyal yardımlardan faydalanmayan 15 kadının katılımından oluşmuştur. Verilerin toplanmasında yarı yapılandırılmış görüşme formu ve derinlemesine görüşme tekniğinden yararlanılmıştır. Araştırma sonucunda katılımcılara yöneltilen 'Sosyal yardımların oy verme davranışınız üzerindeki etkisi nedir ?' sorusundan elde edilen veriler, sosyal yardımlardan faydalanan ve faydalanmayan katılımcılar için ayrı değerlendirilmiştir. 30 şehirli ev kadını ile yapılan görüşmeler neticesinde mevcut sosyal yardım sisteminin kapsamı, amacı, yeterliliği, uygulanışı ve dağıtımındaki adalete ilişkin olumsuz deneyimlerine de bağlı olarak tek başına sosyal yardımların katılımcıların oy verme davranışlarını değiştirmede önemli bir etkisinin olmadığı görülmüştür.The aim of this study is to determine the effect of social assistance on the voting behavior of housewives residing in Adana. Content analysis, one of the qualitative research methods, was used in the research. The population of the research consists of urban housewives who benefit from social assistance and who do not. The working group consisted of 15 women residing in Adana province, Seyhan, Çukurova, Yüreğir and Sarıçam districts, benefiting from social assistance, and 15 women not benefiting from social assistance. Semi-structured interview form and in-depth interview technique were used to collect the data. As a result of the research, the data obtained from the question "What is the effect of social assistance on your voting behavior?" directed to the participants were evaluated separately for the participants who benefited from social assistance and those who did not. As a result of the interviews with 30 urban housewives, it was seen that social assistance alone did not have a significant effect on changing the voting behavior of the participants, depending on their negative experiences with the scope, purpose, adequacy, implementation and justice of the existing social assistance system
Development, characterization, and assessment of antioxidant pectin-sodium alginate based edible films incorporated with cassia essential oil
No full textThis research was conducted in order to develop a sustainable and eco-friendly pectin-sodium alginate-based packaging material using natural additives. Cassia essential oil (CEO) is a GRAS-approved natural preservative and flavouring agent used for a variety of food products. Recent reports revealed the growing interest in using oils in packaging material as natural additives. In the current study, CEO is loaded in pectin-sodium alginate-based composite films. The main component observed in CEO was cinnamaldehyde which was evaluated by employing gas chromatography-mass spectrometry (GCMS) analysis. Moreover, the incorporation of CEO improved the tensile strength (TS) and elongation at break (EAB) and increased the opacity of the films. However, a decrease in the moisture content, water solubility and water vapour permeability was observed with the incorporation of EO. Additionally, SEM analysis of the CEO-loaded films revealed an improvement in their morphology. The results of the DPPH and ABTS cation scavenging assays revealed a significant (P <= 0.05) increase in antioxidant activity with the incorporation of CEO. These findings indicate that cassia essential oil can be employed as a natural additive to develop edible active packaging material. This image illustrates the effect of Cassia essential oil (CEO) on water vapour permeability, morphology, transparency, thickness, mechanical strength, moisture content, and solubility of pectin/sodium alginate based edible films for food packaging application.dagger imageThe authors are thankful to the Natural and Medical Sciences Research Center, University of Nizwa Oman for providing research facilities to conduct the current study.; Natural and Medical Sciences Research Center, University of Nizwa OmanThe authors are thankful to the Natural and Medical Sciences Research Center, University of Nizwa Oman for providing research facilities to conduct the current study
Antimicrobial activity enhancement of PVA/chitosan films with the additive of CZTS quantum dots
No full textThe wound environment is a breeding ground for pathogens, and traditional wound dressing materials lack antibacterial properties. In this work, we aimed to develop PVA/chitosan (P/C)-based wound dressing scaffolds with anti-infective properties using Cu2ZnSnS4 quantum dots (CZTS QDs) to prevent infections in the wound. CZTS quantum dots were prepared by a simple hydrothermal process and characterized using appropriate techniques such as TEM, XRD, FTIR spectrum, and UV-Vis absorption spectroscopy. CZTS QDs were subsequently loaded at different concentrations onto PVA/chitosan membranes (0, 1.6, 2.5 and 3.3% w/w, based on the total polymer quantity). The chemical structure, contact angle and mechanical properties of the membranes were analyzed, and their antimicrobial activities and cell viability were also investigated. The cytocompatibility of the membranes and cell morphology was investigated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and SEM. Based on studies on the interactions between membranes and cells, it was determined that incorporation of CZTS QDs into the membrane did not cause toxicity. To the best of our knowledge, this is the first report on loading CZTS QDs into membranes for tissue engineering applications, and the overall findings suggest that CZTS QDs-integrated membranes might have potentially appealing uses as antimicrobial films for wound healing.Tarsus University Scientific Research Projects Coordination Department [MF.22.003]The authors thank the Tarsus University Scientific Research Projects Coordination Department (Project no: MF.22.003) for the supports