**5. Assessing the quality of Turkish urban design (level of success) by using a fuzzy logic method**

Determining the "urban design" quality of the Turkish cities which have been designed using urban plans is very important for future urban design approaches. In the following sections of this study, the success level will be determined by making use of the evaluations of the relevant and effective actors. In this analysis to be performed using the fuzzy logic method, the urban design criteria specified in the literature will be taken as a basis. The results of the evaluations will be used in analyzing the Turkish cities which come to the forefront with their planned development, in terms of the urban design criteria, and a general evaluation will be made.

Developed by Zadeh in 1965, fuzzy logic is a method for defining and solving the problems having no exact limits [25]. Besides that, it is generally accepted as a way of thinking and deciding in the way closest to the human's way of thinking. In the study of Yager, McNeill and Thro [26], this method was reported to have various positive characteristics such as simplicity, easiness, robustness, and the use of linguistic variables similar to the human's way of thinking. The multi-criteria decision-making methods are used for defining and solving decision-making problems with multiple criteria and repetitive decision-making processes.

The criteria involved in assessing urban design have different complex relationships. Since the urban design criteria are multifactorial and have various sizes and the criteria could not be expressed in a common way, the analysis of the cities in the present study can be formulated as multi-criteria decision-making [27]. In MCDM methods, the opinions of the main actors are requested, and these opinions are directly utilized. Since the specialists make net evaluations while making a decision, useful results may sometimes not be achieved when comparing complex criteria. For this reason, the fuzzy MCDM allowing an analysis of an interval and presenting the evaluations of the specialists within a range was used in the present study.

professional identity in the urban design. These are the professionals working in the private sector, public sector, and NGOs. The common character of these professionals is that they have an effective and specialized structure in the field of urban design. From this aspect, the professional titles of these actors were selected to be an urban planner, architect, and landscape architect. Seventy-three professionals following the urban design processes in Turkey and involved in many processes were involved in the analyses. Among these actors, there are 30 urban planners, 27

Among the selected actors related to the field of urban design, the urban planners are interested in the quality of the built and visual environment, examine the designrelated subjects from theoretical and political aspects, and ensure that they are reflected in the practice. They prepare the projects, which will meet the necessities of future objectives and provide solutions for the problems at different scales. Within the scope of plans, the architects make use of their creativity and implement their original and independent designs. They play a role in the entire project design and implementation process. The landscape architects, however, integrate the physical content, nature, and nature's components with the design by making use of their experience in using the dependence to location/ground and time as an important design element [24]. The decision-makers in this process may significantly vary in terms of person and institution. The effects of powers such as politicians, entrepreneurs, financial institutions, investors, etc. have always been effective on the actors. However, the present study does not involve these powers. It focuses on the evaluations of the main actors about the reflection of design processes on the space.

**5. Assessing the quality of Turkish urban design (level of success) by**

Determining the "urban design" quality of the Turkish cities which have been designed using urban plans is very important for future urban design approaches. In the following sections of this study, the success level will be determined by making use of the evaluations of the relevant and effective actors. In this analysis to be performed using the fuzzy logic method, the urban design criteria specified in the literature will be taken as a basis. The results of the evaluations will be used in analyzing the Turkish cities which come to the forefront with their planned development, in terms of the urban design criteria, and a general evaluation will be made. Developed by Zadeh in 1965, fuzzy logic is a method for defining and solving the problems having no exact limits [25]. Besides that, it is generally accepted as a way of thinking and deciding in the way closest to the human's way of thinking. In the study of Yager, McNeill and Thro [26], this method was reported to have various positive characteristics such as simplicity, easiness, robustness, and the use of linguistic variables similar to the human's way of thinking. The multi-criteria decision-making methods are used for defining and solving decision-making problems with multiple criteria and repetitive decision-making processes.

The criteria involved in assessing urban design have different complex relationships. Since the urban design criteria are multifactorial and have various sizes and the criteria could not be expressed in a common way, the analysis of the cities in the present study can be formulated as multi-criteria decision-making [27]. In MCDM methods, the opinions of the main actors are requested, and these opinions are directly utilized. Since the specialists make net evaluations while making a decision, useful results may sometimes not be achieved when comparing complex criteria. For this reason, the fuzzy MCDM allowing an analysis of an interval and presenting the evaluations of the specialists within a range was used in the present study.

architects, and 16 landscape architects (**Table 1**).

*Sustainability in Urban Planning and Design*

**using a fuzzy logic method**

**334**
