Kamusal alanda kullanıcı hareketlerinin benzetimi için etmen tabanlı bir model önerisi : İzmir Konak Meydanı
An agent based model proposal to simulate user movements in public spaces: Izmir Konak Square
Yazar: BERFİN BERİCAN YILDIZ
Danışman: PROF. DR. GÜLEN ÇAĞDAŞ
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Bilişim Ana Bilim Dalı / Mimari Tasarımda Bilişim Bilim Dalı
Derece: Yüksek Lisans, 2017
Konu: Mimarlık = Architecture

Özet:
Günümüz kentlerinin en büyük sorunlarından nüfus artışı ve buna bağlı düzensiz kentleşme, kamusal alanların yok olmasına, bu sebeple de sosyal hayatın ve hayat kalitesinin zarar görmesine sebep olmaktadır. Bu durum özellikle büyük şehirlerde kamusal alanların önemini arttırmış ve yenilerinin tasarlanması ihtiyacını doğurmuştur. 
Kentsel mekanların tasarlanmasındaki temel odak insan iken, kullanımındaki temel durum ise harekettir. Bu bağlamda kullanıcı hareketlerinin analiz edilmesi, tasarım problemlerinin doğru tanımlanması açısından önem taşımaktadır. Buna bağlı olarak kullanıcı, tasarım parametrelerinin en önemlilerinden biri haline gelmektedir. Kullanıcı hareketleri, tasarımın erken evrelerinde tasarım problemlerinin doğru tanımlanması açısından önem taşımaktadır. Kentlinin kamusal alan kullanımı tasarımı doğrudan etkileyecek önemli bir girdi iken aslında çoğunlukla tasarımı şekillendiren bir kısıttır. 
Kullanıcı hareketlerine etki eden birçok faktör sıralanabilir: insan faktörü, fiziksel yapı faktörleri, doğal yapı faktörleri ve zaman faktörü. Kullanıcı hareketleri açısından insan faktörüne iki farklı açıdan bakmak gereklidir. Bunlar çevrede yürüyen insanların varlığı ve duran insanların varlığıdır. Bu iki durum da değişken bir şekilde zaman zaman hareketi olumlu ya da olumsuz etkiler. Fiziksel faktörlerde ise zemin kat kullanımı, kot farkı, aydınlatma miktarı gibi alt unsurlar yer alır. Bu unsurların kalitesi ve zenginliği, kullanıcı hareketlerini doğrudan etkilemektedir. Doğal yapı faktörleri ise kentsel mekanın sıcaklık, rüzgar, yağmur gibi hava durumları ile peyzaj, manzara gibi etkenleri barındırır. Sıcaklık ve rüzgar gibi dinamik değişkenler de kullanıcı hareketlerini mevsime bağlı olarak etkiler.
Bu tez kapsamında kamusal alanların sahip oldukları fiziksel, çevresel ve işlevsel özelliklerine bağlı olarak kullanıcı hareketlerinin oluşturulabileceği etmen tabanlı bir benzetim modeli önerisi geliştirilmiştir. 
Tezin giriş bölümünde problem tanımı yapılarak tezin amacı, kapsamı ve izlenen yöntem tanımlanmıştır. 
İkinci bölümde ise, kamusal alanda kullanıcı hareketleri incelenirken öncelikle kamusal alanlardan ve kamusallık tanımından bahsedilmiş tezin alan çalışmasına konu olan meydanların özellikleri irdelenmiştir. Ayrıca kullanıcı hareketlerini etkileyen faktörler detaylı bir şekilde incelenmiştir.
Üçüncü bölümde, benzetim modelinin geliştirilmesi sürecinde rol oynayan karar verme yöntemleri incelenmiştir. Bunlar öncelikle elde edilen gözlem verilerinin yorumlanması için kullanılan bulanık mantık yöntemidir. Diğeri ise benzetim modelinin dayandığı temel olan etmen tabanlı sistemlerdir. Bu bölümde kullanıcı hareketlerinin benzetimi için kullanılan etmen tabanlı model yazılımları ile bu yazılımlar kullanılarak gerçekleştirilmiş alan çalışmaları birlikte incelenmiştir.
Dördüncü bölümde, modelin geliştirilmesinde kullanılan etmen sistemlerin hareket yöntemleri açıklanmıştır. Sonrasında, geliştirilen modelin uygulanması için gerekli verilerin toplanması ve yorumlanması süreçleri açıklanmış, modelin uygulanması ile beraber sonuçları irdelenmiştir.
Son bölümde ise, geliştirilen model ile ilgili varılan sonuçlar açıklanmış ve değerlendirilmiştir. Benzetim modeli çıktıları ile gözlem sonuçlarının büyük oranda paralellik gösterdiği sonucuna varılmıştır. Bunun yanında modelin kısıtları ile birlikte gelecek çalışma hedefleri aktarılmıştır.

Abstract:
One of the problems of today's cities is population growth which causes rapid and unplanned urbanization. Designing the urban form considering the spatial requirements of the rapid urbanization, lead to increase urban mass whereas reduce urban open spaces. Lack of these urban open spaces results in to damage the social life and quality of life for citizens. As a result of that, the importance of the urban open spaces increases and necessity to create new urban spaces occurs. 
People should be the main focus of the design fields in all scale, because they are the users of the design objects. Also users are inputs of the design while plays a role as a constraint. 
The design of urban open spaces is one of the subjects that effected by user movements. While the principle focus on urban design is users, the main usage is movement. Within this context, analysing the user movement is crucial to define the design problems in pre-design phases. 
An agent based model is developed to simulate user movements in public spaces. The model works according to the physical, natural and  human factor of the urban space. As mentioned, users which are the most important parameters of design, constitute part of the simulation models as 'agents'.
The definition of the research problem and motivation are presented in the introduction. Also the scope of the thesis and the applied method explained in this chapter.The research problem can be summerized that, user movements are one of the most important design inputs and constraints but they are not easily predictable. Because of the fuzzy nature of human decision making processes these problems are defined as an ill-defined problems. At that point, the research aimed to be able to simulate user movements in public spaces in the scope of urban squares while using decision making approaches. These approaches are aimed to reach the attractiveness value of the urban square components. The agents in the simulation model, are moving under the attract force according to this attractiveness values.
In the second section, user movements in public spaces are briefly presented. Definitions of public space and publicity have been discussed. The notion of publicity should be examined with the accessibility issue because a public space should be accessible in every sense. The space should be physically accessible that every people can enter. Also, social accessbility refers to citizens from all social class are able to enter the space, spare their time. As a subject of the case study, urban squares are chosen and discussed. The urban square can be defined as an urban void. The relation of the urban solids and voids are important for urban fabric and urban life. Moreover, urban squares are important in case of transportation, commercial and cultural activities. 
Urban squares as an urban voids are crucial for this study. Because mainly user movements in urban spaces depend on the configuration of the streets. Squares provides citizens to nonoriented and optional move. A person moves as a result of some cognitive processes. The process initiates with the defining aim, and continues with the perceiving, evaulating the aim and process, moving. According to the literature and the observations, user movements are evaluated with the process of the movement. The users are able to go their target directly or varibly. This variability originate the factors that effect the user movements. 
There are lots of factors that effects the user movements such as: human factor, physical factors, natural, seasonal and time factor. We need to analyse human factor from two point of view which is people that move in the public space and people that stay in the public space. Both situation effects the user movement dynamically. In physical factors contain sub-factors like ground floor usage, level differences, illumination level. The qualities of these factors has a direct affect on user movements. Natural factors in urban spaces contain weather conditions like temperature, wind, rain. These dynamic natural factors effect the user movements depends on the season. In case of all the factors, the classification of them is important. First of all, we can classified the factors into two groups : positive and negative factors. Positive factors cause to user change their route while moving closer to the object. Contrarirly, negative factors cause to change their route while moving away to the object. Also another types of classification is seperate the factors according to its stability. For example, components of the urban space like buildings, trees etc. are static factor that effect the movement positively or negatively. On the other hand, as an example the temperature or the amount of wind effect the users positively or negatively depends on the time and season. That's why we defined them dynamic factors.
In the third chapter of the thesis, decision making approaches that are used in the process of simulation model are identified. Decision making is the processes of the defining the problem, evaluating the alternatives, choosing one of them and application. 
First of the decision making approach that is used is fuzzy logic. This approach have been used to interpret the observation data in the thesis. According to Aristotle's binary logic, a proposition can be true or false but fuzzy logic enable the third truth value. To understand the fuzzy logic, first we need to examined the set theory. In the set theory, the element should be an element of a set, or not. In the fuzzy logic, every elements has membership degrees. The decisions, according to pre-defined rules, are made with these membership functions. Specific to this thesis, the membership functions are identified as distance, heating, illumination and population. These functions are defined with linguistic classifications. As an example, for distance membership function, this classification is made far, normal and close.  The result of the fuzzy inference system is attractiveness value which ranging between 0 to 1. 
The other one is agent based systems that constitute the base of the simulation model. Also the literature review of the softwares that used for agent based systems and case studies that have been used these softwares are explained and discussed together. 
In the forth chapter, starting from the softwares that are used to develop the model with opportunities and constraints, the process of the proposed agent based model are explained. The agent based model contains the agents with the defined forces according to the attractiveness values, the environment that presents the urban square. 
To constitute the simulation models;
•	Emitters, the points that agents will start to move, are defined to the starting points.
•	Arrive force is applied to agents to be able to reach the targets.
•	The numbers of users that determinated from the observation studies, are defined as a number of agents. 
•	For the morning simulation model, the day light simulation results are transferred as a heat values.
•	For the evening simulation model, the illuminance simulation results are transferred as an illuminance values.
•	Attract force is applied to agents according to the heat, illuminance and attractiveness values. 
Also the data that are collected from the observations with the observation model and its interpretation processes are identified in detail. The model and its outputs are evaluated comparingly the observations of the urban square.
In the last part, the outcomes of the thesis are explained and evaluated. The outputs of the simulation models are mostly overlap to the observation results. The observation studies are carried out with 10 users in week-days and in winter. Therefore, in summer and week-end usage patterns with more users need to be examined. The future works are  given related to the constraints of the model in this part.