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91.
Computer anxiety: A cross-cultural comparative study of Dutch and Turkish university students 总被引:1,自引:1,他引:0
The purpose of this study is to determine Dutch and Turkish university students’ computer anxiety levels and to find out whether their computer anxiety levels differ according to their culture, gender and computer experience (i.e., personal computer (PC) ownership, computer usage frequency, computer usage level). A total of 106 university students (30 Dutch female, 22 Dutch male, 26 Turkish female, 28 Turkish male) participated in this research. The data were collected through computer anxiety rating scale (CARS) validated by Heinssen et al. [Heinssen, R. K., Glass, C. R., & Knight, L. A. (1987). Assessing computer anxiety: Development and validation of the computer anxiety rating scale. Computers in Human Behavior, 3, 49–59]. The data were analyzed by t-test and one-way-analysis of variance (ANOVA). The results indicated that the Turkish students have significantly higher computer anxiety levels than the Dutch students. The students’ computer anxiety levels do not differ depending on gender. However, post-hoc analysis revealed that the Turkish female students have significantly higher computer anxiety levels than the Dutch female and Dutch male students. Also, results indicated that while the students’ computer experience increase their computer anxiety levels decrease significantly. 相似文献
92.
Shahram Minaei Erkan Yuce Oguzhan Cicekoglu 《Circuits, Systems, and Signal Processing》2006,25(4):559-566
In this paper, a novel second-order voltage-mode filter with single input and six outputs employing inverting second-generation
current conveyors (ICCIIs) is presented. This filter simultaneously realizes negative and positive gain lowpass, bandpass,
and highpass filter responses, and does not require active and passive element matching. The new filter has low active and
passive element sensitivities, and offers orthogonal control of the angular resonance frequency (ωo) and quality factor (Q). 相似文献
93.
Shahram Minaei Erkan Yuce Oguzhan Cicekoglu 《Analog Integrated Circuits and Signal Processing》2006,47(2):199-202
An active circuit suitable for realizing floating inductance, capacitance, FDNR and admittance converter depending on the
selection of passive elements of the circuit is presented. The proposed circuit employs only two dual output second-generation
current conveyors (DO-CCIIs) and does not require passive element matching. The proposed network has a grounded capacitor
for the floating inductance and capacitance simulation. Frequency performance of the circuit is tested using SPICE. 相似文献
94.
Crude oil, coal and gas, known as fossil fuels, play a crucial role in the global economy. This paper proposes new econometrics modelling to demonstrate the trend of fossil fuels consumption. The main variables affecting consumption trends are: world reserves, the price of fossil fuels, US production and US net imports. All variables have been analysed individually for more than half a century. The research found that while the consumption of fossil fuels worldwide has increased trends in the US production and net imports have been dependent on the type of fossil fuels. Most of the US coal and gas production has been for domestic use, which is why it does not have a strong influence on worldwide fossil fuel prices. Moreover, the reserves of fossil fuels have not shown any diminution during the last couple of decades and predictions that they were about to run out are not substantiated. The nominal and real price of fossil fuels was found to change depending on the type. Finally, estimates of three econometric models for the consumption of fossil fuels from 1949 to 2006 are presented which identify the effects of significant variables. 相似文献
95.
Yahya Erkan Akansu Mustafa Sarioglu Kemal Kuvvet Tahir Yavuz 《International Communications in Heat and Mass Transfer》2008
An experimental study was performed to determine the effects of inclination of an impinging two dimensional slot jet on the heat transfer from a flat plate. Local Nusselt numbers and surface pressure distributions were determined depending on inclination angle, jet-to-plate spacing and Reynolds number. The results showed that the location of maximum heat transfer was mainly due to the angle of inclination. As the inclination angle increases, the location of the maximum heat transfer shifts towards the uphill side of the plate and the value of the maximum Nusselt number gradually increases at lower jet-to-plate spacings. 相似文献
96.
97.
Mustafa Erkan Turan 《Water Resources Management》2016,30(12):4345-4362
River flow prediction is an important phenomenon in water resources for which different methods and perspective have been used. Using fuzzy system with black box perspective is one of them. Fuzzy systems have some parameters and properties that have to be determined. This is an optimization problem that can be solved by swarm optimization techniques among several techniques. Swarm optimization are developed by inspiring from the behavior of the animals living as swarm. The study presents two achievements fuzzy system that tuned by swarm optimization algorithms can be used for prediction of monthly mean streamflow and which swarm optimization algorithm is better than the others for tuning fuzzy systems. Three swarm optimization algorithms, hunter search, firefly, artificial bee colony are used in this study. These algorithms are compared with mean performance values and convergence speed. Monthly streamflow data of three stream gauging stations in Susurluk Basin are used for the case study. The results show, swarm optimization algorithms can be used for prediction of monthly mean streamflow and ABC algorithm has better performance values than other optimization algorithms. 相似文献
98.
Artificial Intelligence Review - Heuristic algorithms can give optimal solutions for low, middle, and large scale optimization problems in an acceptable time. The social spider algorithm (SSA) is... 相似文献
99.
The last two decades have witnessed widespread power market reforms in both developed and developing countries that have cost billions of dollars. Among the key aims (and assumptions) of these reforms, there has always been realization of improvements in power sector efficiency. This paper questions the validity of this hypothesis. Using panel data from 92 countries covering the period 1982–2008, empirical models are developed and analyzed. The research findings suggest that the impact of the reforms on electricity industry performance is statistically significant but also limited. The results imply that, after controlling for country-specific variables, application of liberal market models in electricity industries slightly increases efficiency in power sector. Besides, we detect a positive relationship between reform process and the percentage share of network (transmission and distribution) losses in total electricity supplied, meaning that as countries take more reform steps the network losses as a fraction of power generated tend to increase. Moreover, the study puts forward that income level and other country specific features are more important determinants of industry efficiency than the reform process. Overall, contrary to expectations of substantial increases in sector efficiency, the paper concludes that introducing a decentralized market model with competition in the electricity sector has a limited increasing effect on power industry performance. 相似文献
100.
Nuray Erkan 《International Journal of Food Science & Technology》2011,46(8):1734-1738
This study evaluates the effects of different cooking (grilling, frying and steaming) and processing (smoking, salting, marinating and drying) methods on iodine contents of valuable marine and freshwater fish species commonly consumed in Turkey. The highest mean iodine content of cooked fish was determined to be 3.760 mg kg?1, 2.788 mg kg?1, 5.831 mg kg?1 and 6.161 mg kg?1 in grilled anchovy, horse mackerel, Atlantic Bonito and whiting, 0.914 mg kg?1, 1.452 mg kg?1, 3.106 mg kg?1 in steamed bluefish, red mullet. The highest mean iodine content of processed fish was determined to be 2.149 mg kg?1 in smoked mackerel, 0.701 mg kg?1 in salted Bonito, 1.128 mg kg?1 in dried horse mackerel and 7.283 mg kg?1 in marinated anchovy. This iodine values are also above the Upper Tolerable Nutrient Level of 100–150 μg day?1 iodine. 相似文献