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In this study, the vortex formed on the upstream of the frontal water intake structure in a dam lake was investigated by numerical modeling. Using the computational fluid dynamics method, vortex formation for different water levels was examined numerically. The purpose of this study is to prevent the formation of vortex, which can cause serious damage to the hydraulic structure. The water intake structure examined in the study has three units and rectangular shapes. The geometrical areas of each unit in the water intake structure are equal. The discharge and the distance between the side curtain walls were kept constant. The pressure at the inlet of the water intake structure has been changed depending on the height of the water level. The model scale of the water intake is 1/40. Froude model affinity was used as the model scale. In the numerical study, air intakes to the extent of serious damage to the structure and vortex formations have been observed. Visual simulations and analysis results of numerical models prepared and analyzed in FLOW-3D were examined in FlowSight. The first numerical models are based on examining the vortexes in the water intake structure, and the later numerical models are on the structures that prevent the vortexes in the water intake structure. Vortex formation in hydraulic structures is an undesirable physical phenomenon. Especially in dams with hydroelectric power plants, it causes serious damage to energy efficiency loss, water intake structure, shortening the service life of turbines and energy tunnels. Due to these problems, different anti-vortex structures were tested on the numerical model by CFD method in order to eliminate or reduce the negative forces from vortexes. Structures that block the tested vortex may allow to increase the operating water level in the dam reservoir. A new water intake structure model has been created for the solution of this hydraulic problem, which may cause great danger. Thanks to the new models created, it has been observed that air intake and vortex formations occur in a way that will cause less damage to the hydraulic structure in question.

Bu çalışma kapsamında, proje alanı olarak seçilen Trabzon İli, Vakfıkebir İlçesi Kirazlı deresi için Hydrologic Engineering Center-River Analysis System (HEC-RAS) yazılımı ile kurulmuş 1 boyutlu ve 2 boyutlu hidrodinamik modellerle, Q500 debisi kullanılarak, elde edilmiş taşkın tehlike ve derinlik haritaları doğrultusunda en riskli durumu belirleyebilmek için taşkına maruz kalan alanların yer aldığı binalarda nüfus analizi yapılmıştır. Çalışma alanının Doğu Karadeniz Bölgesinde seçilme nedeni, hem meteorolojik olarak fazla yağış alması hem de topoğrafik açıdan taşkın riski taşımasıdır. Daha önce hazırlanan taşkın tehlike ve derinlik haritaları doğrultusunda; taşkından etkilenen insan sayısı, sosyo-ekonomik aktiviteler ve olası ekonomik zararların tahmin edilmesi amaçlanarak taşkından etkilenebilecek yapıların risk durumunu belirlenmeye çalışılmıştır. Taşkın risk durumu belirlenirken Geographic Information System (Arc-GIS) programı ile taşkın derinlik haritasında yer alan konutlar, fabrika, sera alanlarının, konumları ve o bölgede yaşayan nüfus sayısının belirlenmesinin ardından yapıların cinsine göre ekonomik zarar hesaplanmıştır. Yapıların toplam ekonomik zarar değerinin yapıların kendi alanlarına bölünmesiyle taşkın birim zararı hesaplanarak, hesaplanan bu değerlerin birim metrekareye düşen maksimum ve minimum zarar değerleri 0 ile 1 arasında normalize edilmiştir. Nüfus risk durumu içinde yine aynı metot kullanılarak, normalize edilmiş birim taşkın zararı ile nüfus toplanarak taşkın risk durumu belirlenmiştir. Taşkın risk yüzdelerinin belirlendiği bu çalışmada, taşkından etkilenen yapıların durumuna göre de kabul yöntemiyle yapılan standart sapma analizi sonucu tehlike risk dereceleri belirlenmiştir. Bu kapsamda yapılan çalışma sonucu, taşkın zararlarının etkilerini en aza indirmek maksadıyla derenin belirli kısımlarda gerekli taşkın kontrol yapıları ile mevcut sanat yapılarının yeniden yapılması veya iyileştirilmesi ve derenin düzenli olarak yılda bir defa yatak temizliğinin yapılmasının faydalı olacağı düşünülmektedir.

In this study, the Soil and Water Assessment Tool (SWAT) was used to estimate the streamflow, sediment yield, and the identification of soil erosion prone areas at the sub-watershed scale to enrich the water management practices. The upper part of the Euphrates-Tigris basin called as Murat River basin was selected as a study area. Nash-Sutcliffe Efficiency (NSE), coefficient of determination (R2), and percent bias (PBIAS) were used for the assessment of the model performance with the observed data at two gage stations located on the watershed, E21A074, and E21A077. The Modified Universal Soil Loss Equation was used in the SWAT model in order to predict sediment yield and soil erosion. Sediment Delivery Ratio was also computed to identify its relationship with sediment yield at the sub-watershed scale. NSE, R2, and PBIAS for monthly streamflow prediction were calculated as 0.71, 0.72, and -11.6 in the calibration period, as 0.77, 0.79, and -9.1 in the validation period, at the station E21A077, respectively. Daily simulation the results of NSE, R2, and PBIAS were calculated as 0.56, 0.57, and -15 in the calibration period, while 0.55, 0.56, and 1.2, respectively, in the validation period at the station E21A074. The statistical results for monthly sediment yield calibration and validation were calculated as follows: 0.75 and 0.80 for NSE, 0.76 and 0.84 for R2, -0.9 and 12.2 for PBIAS from the station E21A074. 32% area of the total watershed is under severe and very severe soil erosion conditions. Most of the soil erosion occurred at the barren land use and in the sub-watersheds with a slope greater than 25%. Overall, the SWAT model satisfactorily simulated the streamflow and sediment yield at the Murat River basin which may help the researchers in water resource management.

Akarsu yatağının su iletim kapasitesinin çeşitli sebeplerle azalması veya yatak kapasitesinden daha fazla suyun gelmesi halinde yatak dışına taşarak can ve mal kaybına sebep olan taşkın, tedbir alınması gereken önemli afetlerden biridir. Çalışma bölgesi olan Doğu Karadeniz Havzası, hem meteorolojik açıdan fazla yağış alıyor olması sebebiyle hem de topoğrafik açıdan taşkın riski taşıması açısından önemli bir örnektir. Bu çalışmada yerleşim alanları ile tarım alanlarının Doğu Karadeniz Havzası’nın değişik dönüş aralıkları için hesaplanan taşkın tekerrür debilerine karşılık gelen su seviyeleri ve su altında kalacak yerlerin HEC-RAS 1 ve 2 Boyutlu yazılımı kullanılarak hesaplanması amaçlanmıştır. Yapılan çalışmada yerel düzeyde tehlikeler belirlenerek ilgili kurumlar tarafından taşkın yönetim planları hazırlanmaktadır. Bu kapsamda yapılan çalışma sonucu çalışılan alanda taşkın zararlarının etkilerini en aza indirmek maksadıyla mevcut ıslah tesislerinin revize edilmesi ve taşkın erken uyarı sistemlerinin kurulması gerektiği yönünde taşkını önleyici tedbirlerin alınması gerektiği belirlenmiştir.

In many studies it is stated that increase in i

Because of the prevalence of mobile devices, the overuse of social networking sites has become a global phenomenon. Social networking sites (hereafter SNS) give a lot of opportunities for business. First of all, businesses can make advertise their product in an easy way. A lot of SNS users can see companies’ advertisements when they use SNS for a different purpose. For marketing management, attitude for advertising is very important. Because Consumers’ attitude is an important factor in influencing consumers’ purchase intention. Purposes of this study are to (1) identify the effect of habits and perceived ease of use on psychological dependence on SNS; and (2) to explore the relationship between SNS dependence and attitudes toward SNS advertisement. 215 data entries were analyzed through SPSS. Analysis results revealed that social networks have partial impacts on approaches of people who are psychologically bond to these web sites, towards advertisements.

The strategy literature is replete with studies focusing on such strategic and cultural firm-level factors as entrepreneurship and differentiation. Research indicates that these factors are major determinants of superior firm performance in the long-term. Nonetheless, a majority of works in this area has focused on large-scale, multinational firms. Very little is known about the effects of entrepreneurship and differentiation on the financial performances of small and medium-size firms (SMEs). In the present study, I explore the effects of these three critical factors on firm performance using a sample of 70 SMEs drawn from the Turkish Machinery and Equipments Manufacturing Industry. The results suggest that corporate entrepreneurship and differentiation positively affect SME performance. Theoretical and managerial implications of the study findings are discussed.

In this study; the characteristics of sales representatives related to their sales performance such as learning orientation, customer orientation, intrinsic motivation, hardworking and technical expertise were defined as “Critical Success Factors in Selling” and the mediating role of social intelligence between these and sales performance were investigated. Data collected from 376 sales representatives from 125 different companies showed that social intelligence has strong influence over sales performance and plays a mediating role between critical success factors in selling and sales performance.

This study aims to explore the influence of Human Resource Management (HRM) activities and organizational climate on corporate innovativeness level in United States of America. The data is collected through interviews from 546 employees in US. The study first examines the relative influence of seven HRM activities of i) behavior and attitudes (in recruitment and selection) ii) teamwork iii) extensive training, iv) written policies, (v) training in multiple functions vi) performance appraisal and incentives, vii) feedback on innovativeness level. Secondly, the influence of five factors relating to organizational climate are examined. The second group factors are i) support for innovation, ii) workload pressure, iii) cohesion, iv) organizational boundaries and v) organizational ethics. The paper presents the influence of the two groups of factors on corporate innovativeness level.

Baffled chutes are used in irrigation systems, storm water systems, wastewater canal chutes, river training, and drop structures for energy dissipation. Two flow regions occur on the flow surface of baffled chutes. These are black water and white water regions. Knowing the location of the inception point where white water begins to appear on the surface is important for determination of the non-aerated flow region. Thus, cavitation damage can be prevented. In this study, 160 laboratory test results have been used for determining black water length (i.e., length of the non-aerated region) of baffled chutes with stepped, wedge, trapezoidal, and T-shaped baffle blocks. The obtained observation data have been analyzed by well-known soft computing methods such as artificial neural networks (ANN), curve fitting (CF), non-linear regression (NLR) and special extreme learning machine (ELM). The methods’ performance in mapping input data to the output were compared. The mean regression errors calculated by the curve fitting model, ANN, NLR and ELM are obtained as 2.5, 8.0, 11.25 and 0.8 %, respectively. The experimental results show that ELM’s nonlinear system modeling capability is superior to ANN, NLR, and CF.

Burnout, as a factor related to an individual’s success, is defined as being exposed to behaviors that negatively affect performance and mainly refers to chronic stress. This research focuses on the effects of servant leadership on burnout through organizational politics. Data for the study were collected by survey method with participation of 401 employees from 49 different organizations. Obtained data were subjected to factor analysis with SPSS in order to check the internal consistency of the sample. Thereafter, by using AMOS software, confirmatory factor analysis were conducted and with structural equation modeling method research hypothesis of the study were tested. The results revealed that burnout was not emerged by servant leadership through organizational politics. Even though servant leadership is related to a change by creating a vision, this change process does not affect employees negatively because it comprises long-term plans and occurs spontaneously.

The purpose of this study is to examine the perceptions about organizational politics held by members of different organizations and how these affect their perceptions of organizational justice and decisions relating to employee turnover. For this study, 259 completed surveys were obtained from various public and private sector personnel. After the measures used in the study were verified through confirmatory factor analysis, correlation and regression analyses were then conducted in order to determine the relationship between variables. As a result of the study, it was found out that organizational politics had a significant effect on perceived organizational justice and intention to leave. In addition to those results, a significant relationship was further found between perceived organizational justice and intention to leave.

Side weirs are flow diversion devices commonly used in irrigation, land drainage and urban sewage systems. It is essential for hydraulic and environmental engineers involved in the design of side weirs to predict the discharge coefficient correctly. The aim of this study is to present an accurate equation for discharge coefficients along the bend of sharp-crested rectangular side weirs based on a total of 1504 experimental runs. The discharge coefficient of the rectangular side weir along the bend depends on the dimensionless parameters of Froude number in the main channel F1, the angle of bend curvature α, the ratio of weir length to main channel width L/b, the ratio of weir length to radius of main channel centreline L/rc and the ratio of weir height to upstream flow depth p/h1. In particular, the variables L/rc and p/h1 are not seen in any equation for a rectangular side weir located on a curved channel. However, it was found that these dimensionless parameters were significantly important for the overflow rate. Moreover, the equation in the literature needs interpolation in order to obtain the discharge coefficient for different L/b and α values. Therefore, a reliable equation containing all dimensionless parameters for calculating the discharge coefficient was introduced.

Summary A labyrinth weir is defined as a weir crest that is not straight in planform. The increased sill length provided by the semi-elliptical labyrinth side weirs effectively reduces upstream head to the particular discharge. They can therefore be used to particular advantage where the width of a channel is restricted and a weir is required to pass a range of discharges with a limited variation in upstream water level. In this study, the discharge capacity of semi-elliptical side weirs is estimated by using Adaptive-Neuro Fuzzy Inference System (ANFIS). 675 Laboratory test results are used for determining discharge coefficient of semi-elliptical labyrinth side weirs. The performance of the ANFIS model is compared Multiple Linear Regression (MLR) and Nonlinear Regression (NLR) models based on performance evaluation parameters. Comparison results indicated that the ANFIS technique could be successfully employed in modeling discharge coefficient.

This study aims to explore the influence of human resource management (HRM) activities and organizational climate on job satisfaction in Turkish banks. The study first examines the relative influence of eight HRM activities of: (i) behavior and attitudes (in recruitment and selection); (ii) teamwork; (iii) extensive training; (iv) written policies; (v) training in multiple functions; (vi) incentives; (vii) performance appraisal; and (viii) feedback on performance on job satisfaction. Second, the influence of six factors relating to organizational climate are examined, again from the view point of their influence on job satisfaction. The second group factors are: (i) support for innovation; (ii) managerial competence and consistency; (iii) workload pressure; (iv) cohesion; (v) organizational boundaries; and (vi) organizational ethics. The data collected through interviews from 346 employees from 19 banks show that in addition to the positive impact of HRM activities, organizational climate in particular makes a significant contribution to job satisfaction. The paper presents the influence of the two groups of factors on job satisfaction and the mechanisms through which these factors foster job satisfaction and their implications for practitioners.

Side weirs, also known as lateral weirs, are flow diversion devices widely used in irrigation as a head regulator of distributaries and escapes, land drainage, and urban sewage systems. The studies on the subject have been generally focused on rectangular and triangular side weirs located on a straight channel. However, the same is not true for labyrinth side weirs. The current studies deal with sediment transport and scour problems around side weirs and lateral structures. The investigation of the hydraulic effects of labyrinth side weirs to increase discharge capacity of them has been studied in this particular work. In the study, 2,830 laboratory tests were conducted for determining discharge coefficient of labyrinth side weirs, and results were analyzed to find the influence of the dimensionless weir length L/b , the dimensionless effective length L/l , the dimensionless weir height p/ h1 , triangular labyrinth side weir included angle θ , and upstream Froude number F1 on the discharge coefficient, wa...

The purpose of the research is to determine the relationship between individual achievement motive and organizational commitment of employees. With this purpose, to be able to test the relationships between the factors data collected from 412 employees (technical / management staff) working in different public organizations. The factors which have been studied in the research are; about achievement motive (confidence in success, competitiveness - status orientation, focus on work, in charge of individual task) and organizational commitment (affective commitment, continuance or calculative commitment and normative commitment). According to the analysis results; the factors which affect positively to personnel's perception of affective commitment are; confidence in success and being different. The factor which affects negatively to personnel's perception of affective commitment is in charge of individual task. The factor which affect positively to personnel's perception of continuance commitment and normative commitment is in charge of individual task. The results of this research show that there isn't any relationship between factor of focus on work and all organizational commitment factors.

This paper outlines the important role of human resource management practices with a link between corporate entrepreneurship and firm performance. Data were collected from a survey of 124 firms operating in different industries in Turkey. The findings of this study indicated that human resource management (HRM) practices partially mediated the relationship between corporate entrepreneurship and firm performance. In other words, corporate entrepreneurship affects firm performance, both directly and through its effects on HRM practices. In addition to corporate entrepreneurship, it is found that HRM practices explain a significant level of additional variance (9 per cent) in firm performance. The theoretical and managerial implications are discussed.

A labyrinth weir provides an effective way to increase weir crest length without an associated increase in structure width. Labyrinth side weirs have important advantages compared to conventional side weirs in term of discharge capacity, length of the channel opening, and nappe height over the weir. A different equation is needed for each number of cycles to determine the discharge coefficient of labyrinth side weir. Unlike labyrinth spillways, one or two cycles are mostly sufficient for the labyrinth side weirs to accommodate the required discharge. This study examines the hydraulic characteristics of trapezoidal labyrinth side weirs with two cycles in a subcritical situation and the effect on discharge capacity of using single or multiple cycles in side weirs with the same length openings and crest lengths. The results show that a side weir with one cycle has slightly greater discharge coefficient. In addition, the variation of the discharge capacity was investigated for both one-cycle and two-c...

Menfezler belirli bir ihtimalle gelebilecek taşkınlara göre boyutlandırılır.

Authentic leadership, as a new leadership concept emerging from the demand for honest and reliable leaders, has attracted the attention of the business community. The relationship between authentic leaders and their followers is being investigated across many disciplines. This study focuses on authentic leadership in sales management and explores how it affects the task-related outcomes of salespeople, such as learning orientation, customer orientation, intrinsic motivation and working hard. The data for the study were obtained from 364 salespeople and analysed using the partial least squares method. The results indicate that authentic leadership has significant positive effects upon learning orientation (β=0.251; p

A labyrinth weir is an overflow weir, folded in plan view to provide a longer total effective length for a given overall weir width. The total length of the labyrinth weir is typically three to five times the weir width. In this study, a semi-elliptical labyrinth weir was used as a side weir structure. Rectangular side weirs have attracted considerable research interest. The same, however, is not true for labyrinth side weirs. The present study investigated the hydraulic effects of semi-elliptical side weirs in order to increase their discharge capacity. To estimate the outflow over a semi-elliptical side weir, the discharge coefficient in the side weir equation needs to be determined. A comprehensive laboratory study including 677 tests was conducted to determine the discharge coefficient of the semi-elliptical side weir. The results were analyzed to find the influence of the dimensionless weir length L / B , the dimensionless effective length L / l , the dimensionless weir height p / h 1 , the dimensionless ellipse radius b / a , and upstream Froude number F 1 on the discharge coefficient. It was found that the discharge coefficient of semi-elliptical side weirs is higher than that of classical side weirs. Additionally, a reliable equation for calculating the discharge coefficient of semi-elliptical side weirs is presented.

Factors affecting the success of an individual, as an employee, may differ from each other. Burnout, as a phenomenon, is different from the concept of stress. It refers to a concept that an individual is continuously exposed and it distracts employees from the activities by which he or she exhibit his or her performance. In fact, it causes that the individual leaves himself or herself to the flow of environmental factors. In this study, the transformational leadership practices, as a dimension of manager-employee relationship, have been studied. In addition, The effects of organizational policies, by which achievement of an individual is evaluated in terms of recognition, appreciation, expectations and justice, on the level of individual’s achievement, sensitivity and emotional power, were investigated. This investigation was performed based on individual’s own perception. In this study, survey method was used. 401 questionnaires were collected from 49 different companies and institutions. The obtained data were subjected to exploratory factor analysis by using SPSS statistics software. Reliability of factors were evaluated. At the second stage of the analysis we conducted the confirmatory factor analysis and we realized hypotheses testing by the help of structural equation modeling. We used AMOS at this stage. As a result of this study we observed the effects of power sources and organizational policies on burnout perception. Many hypotheses of this study were accepted.

WOS: A1997XU22200014 PubMed: 9355790 Background and objectives: Symptoms due to slowing of gastrointestinal motility constitute an important problem in most patients with primary hypothyroidism. The purpose of this study was to calculate gastric emptying time in patients with primary hypothyroidism using a radioisotopic method. Patients and methods: Fifteen hypothyroid patients (2 male, 13 female) participated in the study. Mean age was 43 (range 38-50) years. Only patients who had been recently diagnosed and had received no previous therapy were included in the study. Radiological and endoscopic examination of the upper gastrointestinal tract was carried out. Patients with gastric outlet obstruction were excluded. Twelve healthy and euthyroid people with no detectable gastrointestinal pathology were examined as a control group. The mean age of this group was 45 (range 35-55) years. Patients and control group received a semisolid meal containing 1 mCi technetium-99m sulphur colloid and measurements were made from the epigastrium. Results: Mean gastric emptying half-time (t(half)) was 112.13 +/- 48.96 min in hypothyroid patients and 57.87 +/- 6.38 min in the control group. Gastric emptying time of the hypothyroid patients was significantly different from the control group ( P< 0.001). There was no correlation between gastric emptying time and serum thyroid-stimulating hormone (TSH) levels. Conclusion: We concluded that radioisotopic study is a safe, rapid and reliable method for determining gastric emptying time in patients with primary hypothyroidism.

WOS: 000276667400022, Among other significant obstacles, inherent nonlinearity in experimental physical response data poses severe difficulty in empirical physical formula (EPF) construction. In this paper, we applied a novel method (namely layered feedforward neural network (LFNN) approach) to produce explicit nonlinear EPFs for experimental nonlinear electro-optical responses of doped nematic liquid crystals (NLCs). Our motivation was that, as we showed in a previous theoretical work, an appropriate LFNN, due to its exceptional nonlinear function approximation capabilities, is highly relevant to EPF construction. Therefore, in this paper, we obtained excellently produced LFNN approximation functions as our desired EPFs for above-mentioned highly nonlinear response data of NLCs. In other words, by using suitable LFNNs, we successfully fitted the experimentally measured response and predicted the new (yet-to-be measured) response data. The experimental data (response versus input) were diffraction and dielectric properties versus bias voltage; and they were all taken from our previous experimental work. We conclude that in general, LFNN can be applied to construct various types of EPFs for the corresponding various nonlinear physical perturbation (thermal, electronic, molecular, electric, optical, etc.) data of doped NLCs. (C) 2010 Elsevier B.V. All rights reserved., CUBAP (Cumhuriyet University-Bilimsel Arastirma Projeleri Birimi) [F-250], This work has been supported by CUBAP (Cumhuriyet University-Bilimsel Arastirma Projeleri Birimi) Project no. F-250. Also we thank to permission given by the authors (some are also the co-authors here) of the paper of literature data [13] used in this paper.