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As a result of increasing competitive pressures together with continuously increasing costumers needs, decreasing production costs and product development times urge companies to adept a systematic product development process. As the product are designed and produced for the costumers, costumer views are vital for the design and it dictates a close collaboration with the costumers. In order to meet their increasing customers' needs, today many companies are seeking the ways to reflect their costumers' voices and requirements into their products and services. A product development process based on rapid, non-problematical and costumer voices will provide companies a market success through developed products and services. An effective new product development process depends on the definition of uneasy customer problems. In today's competitive environment, companies are utilising different methods to define costumers' needs and to develop products accordingly. Nowadays companies are incorporating the lead users having the abilities to see the general future trends of the market and getting important solutions to these future market needs. In this way, the companies both define the changing costumer needs and getting important competitive advantages by entering their products to the market in shorter times. In this study, firstly the importance of the inclusion of the costumers to the creation of new product development process is outlined, the lead user concept is defined, and the lead user method is explained and the importance of this method in product development studies is underlined. Secondly, the main application steps of the lead user method, namely definition of definition of lead users and lead user characteristics, creation of product concept with lead users and lead users' product concept test are outlined in detail. Finally, the success factors in the application of this method are examined and the product development performance scales are explained. In the application stage of the work, a theoretical model explaining the effect of inclusion of the lead users into product development process was developed. As a result of continuously improvement of automotive technology and increase in customers' expectations, the automotive sub-industry has to develop new product and improve the performance of the product they develop. Automotive sub-industry is one of the high value added industries in sustainable, social and economical development of a society and from this perspective it is highly important for Turkey. In this respect, a market survey with a questionnaire in automotive sub-industry was conducted in order to define the effects of lead users considered in the product development process performance independent variable on product development performance dependent variable in the theoretical model. According to the State Statistical Institute (DİE) and Small and Medium Industry Development Organisation (KOSGEB) criterion, 51 out of 210 small and medium sized companies active in automotive sub industry in and around Istanbul and Gebze were responded positively to our questionnaire. 27 of these responded companies were contacted with face-to-face method and 27 of the remaining companies were responded via e-mail. The characteristics of these companies participated in the study are detailed in presented tables. The information gathered from the field survey was analyses with SPSS 11.0 statistical analysis software. In the statistical analysis, it is determined that the dependent and independent variables in the factor analysis are ascertained in the related factors, the scales developed in the reliability analysis are rather reliable. The analysis also revealed that in the correlation analysis there is a meaningful and positive relationship between dependent and independent variables and with the help of simple linear regression analysis it was determined the variable of the inclusion of the lead users in the product development process affects the product development process in high meaningful level and positive manner. Under the light of the current study, the effects of the inclusion of the lead users in the product development process are interpreted from automotive sub-industries perspective. The comments made on this sectoral basis could be considered as a guideline for other companies and the researches. [ABSTRACT FROM AUTHOR]

Extensive researches have been conducted about wave runup on smooth sloped breakwaters all over the world for a long time. Runup behavior on rough rock armored slopes are significantly different even under the same wave conditions. However, investigations on rock armored slopes are very limited. Rock armored slopes such as breakwaters and revetments are high-cost structures that defend the area behind them against severe wave attacks and strong currents. Wave runup is a crucial factor dictating the crest level of these structures. Van der Meer conducted extensive series of physical model tests under random sea states for investigating stability of rock armored slopes at Delft Hydraulics Laboratory, during which runup values are measured simultaneously. After qualitative review of various parameter influences concerning wave runup on impermeable, permeable and homogenous rock structures, Van der Meer and Stam proposed the most widely used formulae for the forecast of dimensionless 2% wave runup elevationas as function of surf similarity parameter by using regression analysis, which is also recommended by the U.S. Army Corps of Engineers, British standards. The regression model consists of two parts, namely linear and power functions.. Hence, it is necessary to consider a transition region which depends on the variable surf similarity parameter. Rock armored slopes are often designed according to the runup level exceeded by 2% of the incident waves, u 2% R /Hs, on the front face of the coastal structure by using Van der Meer and Stam formulae. This parameter is defined as the vertical distance between the still-water level and the elevation exceeded by 2% percent of the runup values in the distribution. This means that, for every 100 waves running up a slope, two waves would have a runup elevation exceeding the level estimated by R From the literature survey, it is seen that the two most important factors influencing runup phenomena on rock armored slopes are structure permeability and surf similarity parameter Since the relationships between wave runup and these parameters are complex, vague and uncertain in nature, it is quite difficult to adequately examine wave runup by conventional regressional approaches. Here, an attempt is made to construct various Takagi-Sugeno (TS, 1985) fuzzy models for predicting the 2% wave runup on rock armored slopes. The key task in developing a satisfactory forecasting model in the TS approach is the selection of appropriate input variables and numerical counts and types of Membership Functions of these variables, which determines the architecture of the model. Subsequently, the premise and consequent parameters are optimized by using ANFIS learning procedure. ANFIS, free of restrictive assumptions, optimizes premise and consequent parameters by gradient descent and least-squares methods, respectively, in order to best learn information about the dynamic system and does not contain any transition regions, as in the Meer and Stam equation depending on surf similarity parameter. In this study, many ANFIS models with different architectures are trained with the same 100 training data of Van der Meer and Stam. The training performance of each model is accomplished within a short time. They are compared with conventional empirical model of Van der Meer and Stam and with one another by using the 161 test data. As a result, the system with two inputs, namely structure permeability and surf similarity parameter, and each of which is assigned three trapezium MFs provides a smaller error compared to the empirical and other constructed ANFIS models and therefore is selected. In the constructed model, structure permeability and surf similarity parameter variables are initially assigned three trapezium MFs with equal base widths. Then each parameter in the membership functions in the premise part of fuzzy IF–THEN rules that changes the shapes of the membership function is set to an appropriate value to match the output data of the training data by using the back propagation algorithm. This leads Structure Permeability and Surf similarity parameter variables to different trapezium shapes. The developed fuzzy model with two inputs namely structure permeability and surf similarity parameter yielded the best result out of all constructed models and is proposed in this study. The presented model is validated by comparison with widely used empirical model of Meer and Stam recommended by the U.S. Army Corps of Engineers, using the experimental data-sets of Van der Meer and Stam. The verification process is obtained through scatter diagrams and two numerical error criterias. It was found that the Fuzzy Logic model produce better accuracy in performance than the Van der Meer and Stam’s empirical model. [ABSTRACT FROM AUTHOR]

As a result of increasing competitive pressures together with continuously increasing costumers needs, decreasing production costs and product development times urge companies to adept a systematic product development process. As the product are designed and produced for the costumers, costumer views are vital for the design and it dictates a close collaboration with the costumers. In order to meet their increasing customers' needs, today many companies are seeking the ways to reflect their costumers' voices and requirements into their products and services. A product development process based on rapid, non-problematical and costumer voices will provide companies a market success through developed products and services. An effective new product development process depends on the definition of uneasy customer problems. In today's competitive environment, companies are utilising different methods to define costumers' needs and to develop products accordingly. Nowadays companies are incorporating the lead users having the abilities to see the general future trends of the market and getting important solutions to these future market needs. In this way, the companies both define the changing costumer needs and getting important competitive advantages by entering their products to the market in shorter times. In this study, firstly the importance of the inclusion of the costumers to the creation of new product development process is outlined, the lead user concept is defined, and the lead user method is explained and the importance of this method in product development studies is underlined. Secondly, the main application steps of the lead user method, namely definition of definition of lead users and lead user characteristics, creation of product concept with lead users and lead users' product concept test are outlined in detail. Finally, the success factors in the application of this method are examined and the product development performance scales are explained. In the application stage of the work, a theoretical model explaining the effect of inclusion of the lead users into product development process was developed. As a result of continuously improvement of automotive technology and increase in customers' expectations, the automotive sub-industry has to develop new product and improve the performance of the product they develop. Automotive sub-industry is one of the high value added industries in sustainable, social and economical development of a society and from this perspective it is highly important for Turkey. In this respect, a market survey with a questionnaire in automotive sub-industry was conducted in order to define the effects of lead users considered in the product development process performance independent variable on product development performance dependent variable in the theoretical model. According to the State Statistical Institute (DIE) and Small and Medium Industry Development Organisation (KOSGEB) criterion, 51 out of 210 small and medium sized companies active in automotive sub industry in and around Istanbul and Gebze were responded positively to our questionnaire. 27 of these responded companies were contacted with face-to-face method and 27 of the remaining companies were responded via e-mail. … [ABSTRACT FROM AUTHOR]