Measuring urban slum area imageability through visual indicators

Imageability is the quality of a place that makes it recognizable, memorable, and different from other places. It determines the character and identity of city space. On the other hand, slum settlements are a severe problem in several countries worldwide. Urbanization makes urban space denser and causes disorder if there is no good urban spatial development. This condition then affects the image of the city, which becomes less good, disorganized, and has no character. In its role, good quality (non-slum) urban settlement will improve the image of the city. However, in the context of slum settlements in Indonesia, under certain conditions, it can have good imageability as part of the identity of urban settlements. This paper aims to assess the imageability of the slum area of Mojo Village, Surakarta City, which will be used as a basis for settlement upgrading. This study uses a qualitative method with a visual assessment survey using the main parameters of the condition of the open spaces and buildings. A visual assessment survey is a survey to assess visual quality by observers with predetermined assessment criteria. This study found that predominantly settlement neighborhoods have low imageability, but some places have high imageability.


Introduction
The city of Surakarta in Central Java is one of the cities facing the problem of slum settlements. Based on the Decree of the Mayor of Surakarta Number 640/69.9 concerning the Location of Slum Settlement in Surakarta City, Surakarta City has eight areas spread over 29 villages, including slum areas with a total area of 135.97 ha. The Semanggi area is included in the largest slum area, with 35.45 ha spread over the Kedung Lumbu, Sangkrah, Semanggi and Mojo Villages [1]. Mojo Village is a division (pemekaran) of Semanggi Village in 2018. In 2020, the settlement area of Mojo Village was in the City Without Slums (KOTAKU) program of the Central Java Provincial Government. The program focuses on constructing new livable housing on previously cleared land and the construction of supporting infrastructures such as roads, sanitation, drainage, garbage, clean water, and fire mitigation.
In the 1960s, Kampung Silir was located in the Semanggi Village (before the division) and became a place of localization (prostitution) [2]. Historically, during the independence period, the city government tried to eliminate the practice of prostitution, which was rampant in the city of Surakarta, with various regulations and policies. However, this effort was considered less than optimal. In 1997, the localization was officially closed by the government. Furthermore, the government is trying to improve the population's skills to find a more decent income. The government also turned the area into a center for selling animals (chickens and goats) and used goods. Over time, there was also the construction of educational facilities, health, and several government agencies. Mojo Village itself IOP Publishing doi:10.1088/1755-1315/1082/1/012027 2 dominates residential areas located in suburban areas ( Figure 1). Even so, the Mojo village, with its mixed-use function is expected to be able to support the city in realizing a liveable city.

Figure 1. Mojo District Context in Surakarta City
In recent years, this area has received the KOTAKU program, a slum environmental upgrading program from the government. Some slum criteria have been handled well so that some RTs are no longer included in slum areas, while in other areas, they are still classified as slum areas because they have not received more attention (Figure 2). Even so, the imageability of the area is not considered suitable as a built environment area. Apart from the delineation of slums, several buildings, mainly commercial functions, are in poor condition, making the visual image less suitable.
Imageability in Mojo District needs to exist and be improved because Mojo is a suburban settlement area that tends to be densely packed. Most of the residents get their income from the economic sector around settlements. Some residents sell in the markets, become casual laborers, and have commercial activities along the corridor, as well as in the informal sector, such as food stalls and angkringan. With high imageability, it will increase people's interest to come and conduct economic transactions. In addition, it certainly increases the sense of belonging to the place and builds good social relations with fellow residents and visitors. An excellent urban environment should have a good image to support the city's liveability both economically, socially, and environmentally. This research needs to explore the factors that influence the urban space imageability so that these factors can be the basis for improving the existing conditions of imageability. This research aims to assess the imageability of the urban slum area environment by looking at its physical elements.

Literature Review
Imageability is the quality of a place that makes it recognizable, memorable, and different from other places [3]. A place has high imageability when certain physical elements and arrangements attract attention, evoke feelings, and create a lasting impression [4]. The image of the city is formed based on IOP Publishing doi:10.1088/1755-1315/1082/1/012027 3 the response between residents and environmental, economic, social, and technological developments that reflect the local climate in the city [5]. The image of the city is also related to the ease of orientation and feelings of security and comfort in the city [3]. The development and growth of the city is a continuous process so that its shape, character, and image develop over time as a result of the development of urbanization with a paradigm shift [6].
There are four important roles when the city has a clear city image. First, is the mobility function, which allows people to move easily. Second, the image serves as a broad frame of reference for the structural knowledge of the city and the activities within it. Third, is the emotional function where a clear image allows a person to move into the city with a sense of comfort, ease, and emotional security. Finally, the image of the city has a symbolic function by providing symbols and strong associations with a place [7] [8]. Those can support the community to interact well with the environment. Therefore, to maximize the relationship between humans and their environment, the city must be designed to maximize its image by considering the factors that make up the city's image [9].

Methods
The research method used is a qualitative method for the assessment of imageability. Previously, slum areas had been assessed to see the latest slum conditions with slum criteria from government regulations. Imageability parameters are public open spaces, significant landscape features, buildings with signage, buildings with non-rectangular shapes, and the presence of outdoor dining [4] (Table 1). These physical elements will be mapped in a predetermined delineation of slum locations.

Visual Assessment Survey
Researchers will assess the condition of imageability based on field observations to see the physical aspects as visual indicators. Visual appraisal attempts to measure how individuals perceive their environment and better understand what individuals value in their environment, also adding another important quality [10]. Researchers will use a Likert scale of 1-5 with particular criteria for each parameter (Table 1). These assessment criteria describe the condition of the physical elements as visual indicators in each parameter.  Figure 3). The location has potential commercial points such as a chicken and goat market, a place to sell used goods, Klithikan Notoharjo Semanggi Market, and the most significant selling scrao iron in Surakarta, namely Pasar Besi Tua Semanggi (Figure 4). In several locations, there is a dominance of the Mojo Village residential area, where some of them are in seedy condition according to the Mayor's Decree on the Location of Slum Settlement in Surakarta City. Observation spots are buildings and areas according to the imageability parameters, and the spots are marked with numbers sequentially that mark the order of assessment from beginning to end ( Figure 5).

Current slum condition in the area
The last slum assessment by KOTAKU was carried out in 2020, and since 2017 the government has begun upgrading slum areas in this Mojo village. Until 2022, there have been many improvements to reduce slum conditions. Therefore, the researcher reassessed the slum areas, especially RW 01, 02, and 03. The current condition of slums is as follows ( Figure 5).  From the imageability assessment in the Mojo residential area, it can be seen that on the parameters of public open space, the major landscape features and buildings are in poor condition. On the parameters of public open space, several open areas are managed independently by the community with improvised designs without any unique creations or innovations. Even though public amenities are an important factor in creating good quality urban space [11]. In the parameters of the main landscape elements, the majority have not been designed or are in an abandoned condition. However, some spots are used by the community for farming and as a means for children to play. Those are related to the freedom to do activities in public spaces, where the public feels free to use the space with a sense of belonging to increase their social interactions [3]. In the outdoor dining area, most food stalls have not been arranged, and there is no particular design where some of them occupy the shoulder area. Buildings with non-rectangular silhouettes are in poor condition, especially in commercial buildings such as scrap iron trading buildings, because they use improvised materials. Some that are already in good condition are government buildings, such as mosques, junior high schools, as well as kindergartens and health centers.

Figure 5. Slum Mapping and Observation Spot
Buildings with signage are also almost where government buildings have good quality and are well maintained with clear signage, such as the Pasar Kliwon Koramil building and the Semanggi IKM Center. Unfortunately, market buildings such as the Chicken Silir Market and Klithikan Notohardjo Market have different conditions; the buildings are not well maintained, the roads are flooded, and the material's quality is not good. Although the existence of this market is very busy with buying and selling activities, it is not surprising because the three markets are the largest in Solo City, even Soloraya. Klithikan Notohardjo Market is the largest market for buying and selling used goods, Chicken Silir Market is the largest place to buy and sell chicken, and the Old Iron Market is the center for buying and selling scrap or scrap metal in Soloraya. In Rahman's research, areas and areas along roads that are poorly maintained and less clean give a bad impression and create feelings of insecurity and discomfort for road users [11].
Even so, the Mojo residential area, at some point has a strong historical trace as part of the power of the Surakarta Kasunanan Palace in the past. The historical traces are like the gate to enter the Surakarta Palace area, which has large and small sizes as well as Rajamala boats. The large gates are located in the Grogol, Kerten, and Jurug areas, while the smaller ones are in the Solo Baru area, the Makam Haji, and one is in Mojo [12]. Kyai Rajamala boat is a boat belonging to the Surakarta Kasunanan Palace with 58.9 x 6.5 meters. The paddleboat has a length of 6.6 meters and is now stored in the Kraton Surakarta Museum [13]. The replica of the boat was then made in Mojo as a distinctive landmark in the Mojo settlement area. From this assessment, it can be found that the factors that can affect the imageability of the area are the presence of public amenities, maintenance, and cleanliness [11]. In addition, historical value can also increase the imagination of urban space that represents the city's historical identity. Historic city space or urban space related to cultural heritage is the cultural capital of urban places, essential in shaping the future historical urban space [14].
Urban spaces can be designed to meet all technical requirements, but randomly combined details, materials, and colors can reduce their visual quality [15]. Moreover, technical adequacy conditions that are not met, such as minimal building maintenance and cleanliness, will further reduce the visual quality of urban spaces. In addition to working on space and detail, it is often possible to make significant quality improvements if urban spaces are designed to bring out the unique character of the location. Surakarta with a strong cultural and historical city background should have a distinctive urban space character that distinguishes it from other cities in Indonesia. New and exciting combinations are possible when urban spaces can be connected directly to water elements and riverbanks, and interaction with gardens, flowers, and landscapes; then spaces can be well-designed where appropriate to the local climatic context [15]. Trees, landscape management, and flowers play an essential role in shaping the image of the city. Trees can also define urban spaces and highlight important areas, providing shade, conditioning, and purifying the air. In another aspect, the green element in the city has a symbolic value. Its existence can convey the meaning of space-related to recreation, introspection, beauty, sustainability, and natural diversity [15]. This will at some point create comfortable and adequate public amenities.
From the discussion that has been raised, the condition of imagination in the observation spots in the slum neighborhood area is at a low level, especially in abandoned public open spaces, untreated landscape elements, irregular food stalls, buildings with non-square shapes but does not show a special character, as well as buildings with markers but in unkempt and unsanitary conditions. The observation spots with a fairly high level of imagination are found in the landscape element area with landmarks that have historical value to the city as well as buildings with unique or distinctive styles, characters, and architectural elements. The factors that affect the condition of imageability are the existence of adequate public facilities, the level of care, the level of cleanliness, and the existence of historical values.

Conclusion
This paper emphasizes the assessment of the imageability of the area through visual assessment surveys in the slum area in Surakarta City. The assessment is carried out based on the imageability parameter through the most influential elements, namely public open space, major landscape features, buildings with non-rectangular shapes, and buildings with signage. The research shows that the assessment of these elements shows that the dominance of the imageability value is not good. Due to the existence of public amenities that have not been appropriately managed, the level of maintenance and cleanliness is low. Some points with a high enough imageability are areas that show the historical value unique to the place. Seeing these things, certain factors become very influential on the level of imageability in urban spaces. These factors include the existence of adequate public amenities, the level of maintenance, the level of cleanliness, and the presence of historical values. The findings of this study will contribute to strengthening the imageability of the Mojo settlement area. Strong neighbourhood imageability will support increased liveability of urban space both economically, socially, and environmentally.