Enhancing workers’ quality of life: why land use mix should be increased? (Case study: Semarang City)

Nowadays, many urban workers are struggling and exhausted because of commuting activity due to the effect of urban sprawl. In order to overcome the externalities of the sprawl, many cities are directed to become more compact, to reduce travel time and cost. The efficiency that comes from the proximity of mixed-use development helps workers allocate time and money for participating in other activities and indirectly increases their quality of life. This article reviews the importance of increasing the land use mix to facilitate workers’ activities. The network and entropy index analyses are used to examine the land use mix in the study area. Then the result is discussed in the context of the travel behavior approach theory. The result shows the aggregate land use mix in the study area is moderate-mix with an index of 0,47. In detail, areas under 2 kilometers have a high mix of land use (0,63-0,74), but the value decreases as it moves away from the city center to an index of 0,4. This study reveals that increasing number of land use variants does not improve the land use mix, but balancing the proportion of land use area is more important to increase the mix. It is necessary to improve land use mix because there are approximately 6.939-13.877 workers in the area that should be facilitated so they might participate in other activities effectively. Workers with a simple trip chain might be facilitated handily. But as the land use mix increases, workers with a complex trip chain might fulfill their needs within the area. Integrating land use and transportation allows workers to make active trips, which can affect their health and quality of life.


Introduction
The concept begins with individuals moving to other places to meet their needs that cannot be fulfilled in the same location [1].It also leads us to understand that a trip is derived from a need to participate in an activity.Human activities can be categorized as subsistence, maintenance, discretionary, and commuting activity [2].These varieties of activity require space, and so on, it implicates land use.Due to the lack of land use control, city development is spreading out horizontally and making it sprawl.It separates residence locations and works, even increasing travel time and cost.
The separation of residence and work location should be minimized to consider the convenience of commuting trips to participate in subsistence activities.It is noteworthy because subsistence activities have the most significant motivation to make people travel [3].Due to fulfilling their needs, human is obliged to work, requiring them to make trips to their office in another place and often closer to the city center.The commuting activity should be done regularly, five days a week.It could be stressful and 1318 (2024) 012019 IOP Publishing doi:10.1088/1755-1315/1318/1/012019 2 tiring if commuting takes hours.Workers with long commute times exhibit adverse health outcomes, such as stress, exhaustion, sleep disturbances, and illness [4].Commuting affects work and family life and is subsequently associated with lower well-being and decreased physical and mental health [5].
Urban sprawl creates excessive land consumption and exponentially increases resource and energy use.In order to overcome the externalities of urban sprawl, many cities are directed to become more compact.It is already common that compact development with a high mix of land use functions is more advantageous rather than low-density or mono-functional land use [6].Mixed land use facilitates inhabitant to participate in activities within a neighborhood, reducing private car use, travel distance, and travel time and minimizing the energy consumption for these activities [7].Mixed land use becomes a key point for compact development and subsequently affects urban sustainability because it can minimize regional energy consumption and carbon emissions, promote residents' health and urban living, and make the urban environment more livable [7][8].
Along with urban development, it seems urgent to evaluate land use based on activity-based and travel behavior approaches to increase accessibility.The concept of accessibility emphasizes the integration between transportation and land use development that comforts people to make the trip [9].Considering the human scale, especially in how and when the inhabitant makes the trip, can lead us to understand the pattern of their activities.It can be the input to arrange land use mix and to add urban functions based on demands.This study examines the land use mix in the study area, and the results are assessed using a travel behavior approach.The comparison between the existing condition and the theories enriches planners' consideration to add urban functions to increase the land use mix.

Method and Data
This study used the quantitative approach and operated the network analysis to determine the study area and the entropy index analysis to assess the land use mix within the study area.Also, the descriptive analysis was used to elaborate the result based on the travel behavior theory.Hereafter is the approach to determine the study area in the research.
An illustration used to determine the study area by considering the convenient travel time for daily commuting and the willingness to walk distance (see Fig. 1).The workplaces' location tends to be in the city center, and it should be reached with a comfortable travel time of 30 minutes, including the time to walk.If the willingness to walk in Semarang city is approximately 160-179 meters [10], then the interaction between land use within that radius should be higher where the transportation node is the center.Thus, the study areas were selected with the criteria within 160 meters and 5-minutes walking distances (400 meters) near transportation nodes in origin (residential) and destination (office) areas.The data used in this network analysis measurement was traffic data of Semarang City 2016 that projected into present traffic conditions.After the study areas were determined, the entropy index measurement assessed the land use mix.The entropy index is a measurement to define land use mix, which considers the relative percentage of two or more land use types within an area as described in equation 1.The value varies from 0 to 1, so it can be interpreted that the study area has a high level of land use mix when the value is closer to one.The value may also divide into five classes (with 0,2 points interval range) and classified as very low, low, moderate, high, and very high-mix land use [11].Even though this measurement is debated because it is just a statistical approach and does not consider the distance of each land use [7], it can always be the initial measurement to evaluate the land use mix of an area.The data used to measure the entropy index was land use data produced by the Bappeda of Semarang City in 2016 that were reclassified according to the newest Minister for Agrarian Affairs and Spatial Planning's decree (Permen No. 14 Tahun 2021).
As mention before, the land use mix will facilitate workers to move easily before or after work hours.The travel patterns of workers participating in other activities will form a complex trip chain such as H-X-W-H, H-W-X-H, or H-X-W-X-H [12].The "X" notation represents a place where inhabitant do an activity, such as shopping, taking children to school, hanging out at cafes, and others, while the "H" stands as the home and the "W" stands as the workplace.

Result and Discussion
Workers make the commute trip regularly, so as the potential regular passenger, their needs should be prioritized by urban-transport planners.Ideally, workers would be comfortable and enjoy the journey if they do daily commuting trips with a maximum time of about 30 minutes.However, during the commute trip, planners should be aware of the individual workers' needs that make them require to participate in other activities at different locations, which will affect the workers' trip chain.With this worker behavior, urban planners are challenged to integrate transportation and land use to make workers' trips more seamless.

Figure 2. The coverage area based on a convenient time to commute to the Semarang City Center
This study has considered the convenience time of commute trips to estimate the travel coverage area and land use conditions within the study area.Estimation is conducted by utilizing network analysis with the criteria of the 20-minute trip by motorized from the center of Semarang City.Each Trans Semarang shelter located within the coverage area is used as a new point to perform the subsequent network analyses to define the coverage area with the criteria of the 5-minute walking trip (equivalent to 400 meters).In addition to walking time, network analysis is also carried out to determine the coverage area based on willingness to walk with a distance criterion of 160 meters.
Based on the approach, the coverage area of the 20-minute trip by motorized vehicle is 13,095.81hectares or equivalent to 35.04% of Semarang City's area, where 409 Trans Semarang bus shelters are located and served the area (see Fig. 2).With those shelters as a center, network analysis forms 3,540.93hectares as the 5-minute walking trip coverage area which is equivalent to 10.64% of the Semarang City's area (see Fig. 3a).The coverage area of the Trans Semarang bus shelter is getting smaller when using the distance criteria of willingness to walk, which is 587.23 hectares or equivalent to 1.92% of the Semarang City's area (see Fig. 3b).Both coverage areas are used as a boundary to estimate the land use mix around Trans Semarang bus shelters.The entropy index measurement assessed the land use mix.In aggregate, the land use mix in the 5minute walking trip coverage (400 meters) from the Trans Semarang bus shelters is 0.47, or a moderate mix level.However, the land use mix value increased to 0,58 in the 160-meter distance coverage, but it is still in the moderate mix level.Although classified into the same mixed-level category, the land use is more diverse as it is closer to the bus shelter.In the study area, the value differentiation among both areas occurs because of a large amount of residential use in the 400-meter coverage area compared to other land use variants, and it is affecting the balance (see Fig. 4).
In the 400-meter coverage area, the residential area is 2.147,29 hectares.With that amount and considering the population density, which is 8,078 people/km 2 in the city center (BPS Semarang City, 2021), this area serves approximately 173,467 inhabitants or the equivalent of 34,693 households with single or dual-earners in each household.This study assumes that there are 6,939-13,877 workers which are accommodated by Trans Semarang services and could make commute trips in less than 30 minutes.If the land use has a high mix, it will reduce the need for workers to make additional trips to fulfill their needs outside the area.However, this study shows that the possibility of individual workers traveling outside the area is still high because the aggregate land use mix level is moderate-mix with a value of 0.47.It also needs further study because trip efficiency can only be realized if a variety of activity options has met the needs of workers.
The level of land use mix around the Trans Semarang bus shelter increases as it is closer to the city center and decreases further away from the city center (see Fig. 5).The land use mix within a 1-kilometer radius has a value of 0.74.The value reduces to 0.63 in the area of kilometer 1 to 2 and continues to decrease as it moves away from the city center.An interesting thing was shown on kilometers 7 to 9 from the city center, where the entropy index value bounced back.It can be a suggestion for workers that looking for a place near bus shelter, to avoid the residential in kilometers 6 to 7 from the city center because these locations have the lowest land use mix.It represents a low variety of activity options that could facilitate individual workers to meet their needs.However, this study also shows that the more significant number of land use variants in an area does not affect the value of the entropy index (see Fig. 5).This is because the value of the entropy index is dependent on the balance of land use's proportion in the area.Therefore, efforts to increase the level of land use mix could not focus on increasing the number of land use variants but also on balancing the proportion of land use area.In addition to increasing the land use mix in the study area, individual workers must also be willing to walk further, which is more than 160 meters.Based on the 160-meter coverage area of the Trans Semarang bus shelter, there is a residential land use of 258.75 hectares, so the study estimated that approximately 836-1,672 workers have potentially walked from or to the Trans Semarang bus shelter.This number is only 12% of the total estimated workers in the study area, so there are 6,103-12,205 individual workers who could be encouraged to walk or make other active trips.The opportunity for individual workers to travel actively is quite significant because 70% of workers who work in the center of Semarang City have a simple trip chain, especially workers who are not married, do not have child, or do not have school-age children [13] .Individual workers with a simple trip chain might be more easily encouraged to make active trips by taking advantage of proximity to transportation nodes.An active trip such as walking, cycling, and public transport will improve the workers' health and quality of life.It will also reduce the use of private vehicles and carbon emissions.
In the long term, efforts to integrate land use with transportation system can facilitate the convenience of individual workers in meeting various needs, e.g., increasing the land use mix.The availability of options in a compact area will attract individual workers with complex trip chains to meet their needs inside the area.Complex trips are formed because workers participate and travel to other places to carry out non-work activities, as shown by the "X" notation in the trip chain (see Table 1).However, with an increase in the land use mix, the diversity of activity options provides proximity between places, so individual workers' trips can be more efficient.It allows individual workers to allocate remaining time and cost to participate in other activities.

Conclusion
Urban governance has the primary outcome of realizing the urban communities' welfare [14].It begins by providing livable urban space as a place to live, work, and seek entertainment to improve the quality of life.Quality of life is influenced by many factors, including how individual workers make travel to work.Commute trips that take hours will reduce the comfort level, and the impact will accumulate negatively on the workers' well-being.Therefore, it is necessary to integrate transportation and land use to reduce the negative externalities of workers' trip routines.Efforts to increase the land use mix will facilitate individual workers to meet their needs through various available options for activity, especially in areas around transportation nodes.Based on the study's results, the aggregate land use mix in the convenient travel time area (within 30 minutes) has a mixed land use with a moderate level (entropy index 0.47).Partially, the land use mix in areas less than 2 kilometers has a high mixed-use level with an entropy index value of 0.63-0.74.It is quite good but still ought to be progressed, especially in the areas within kilometers 3 to 9 from the city center, where the entropy index is decreased in the range of 0.40-0.58(see Fig. 5).It can be a suggestion for workers that looking for a place near bus shelter, to avoid the residential in kilometers 6 to 7 from the city center because these locations have the lowest land use mix.However, the land use mix should be improved, and urban planners should be focused on balancing the proportion of land area more than just increasing the number of land use variants.It is because increasing the number of land use variants is not directly proportional to the entropy index value.
Integrating land use and transportation will create proximity between places to streamline workers' travel time and costs to participate in the activities.The estimated population served within the convenient travel time coverage area is 173,467 inhabitants, and this study assumed that there are 6,939-13,877 workers among them.Workers could generate many trips as a trip derived from a need to participate in an activity.So, the increase in the land use mix is expected to provide more options for individual workers to meet their needs inside the area and to reduce cross-regional trip, especially for workers with a complex trip chain.The activity diversity around transportation nodes is expected to ease travel, so individual workers consider taking active commuting trips, such as taking public transportation and walking on their first-and last-mile trips.Therefore, workers will perform physical exercise that naturally helps improve their fitness and health and increases their quality of life cumulatively.

Figure 1 .
Figure 1.The study area determination approach

( a )Figure 3 .
Figure 3. Land use around Trans Semarang shelter

Figure 4 .Figure 5 .
Figure 4. Comparison between the two coverage areas in terms of land use area and its distribution

Table 1 .
Workers' trip-chain for working purposes in Semarang City