Improving Sustainability Asset Performance Based on Dynamic Data Envelopment Analysis

The success of an industry is often measured through sustainability performance because it serves as a benchmark of consideration for asset managers in carrying out actions, planning, and decisions. However, changes in the utilization of physical assets between entities impact not only the life cycle of these assets but also sustainability assets that will affect company performance in terms of controlling company efficiency. The DDEA method is an analytical method that can be used to assess the level of efficiency of the performance of sustainability assets. The performance of sustainability assets is measured using variable maintenance costs, asset availability, material consumption as an economic aspect, variable environmental impact costs, employee health costs, and accidents and incidents as social aspects. In addition, material rejects variables, hazardous waste, and energy consumption costs as environmental aspects. From the results of the analysis of sustainability asset performance through the DDEA method in the period 2018–2022, it shows that both before and after organizational changes have no significant impact. This is shown by the level of efficiency of sustainability asset indicators on the impact of organizational change found in DMU 1, DMU 2, DMU 3, DMU 5, DMU 6, DMU 9, and DMU 10. The achievement of constant or efficient conditions with input-oriented CRS efficiency is at a score of 1. While DMU 4, DMU 7, and DMU 8 show increasing conditions with input-oriented CRS efficiency at less than 1.


Introduction
In the current era of disruption, not only individual businesses but all industries and business ecosystems are required to be able to compete and survive the conditions of the new business model changes that occur [1], [2].Various defenses are built by each industry to continue to exist in this era of disruption, including by making changes in the organization to be more agile [3], [4].
This conception is also supported by [5], who argue that more agile organizational changes can increase efficiency and effectiveness.State-owned enterprises (SOEs) of the Republic of Indonesia are also not spared from the impact of disruption, which further changes business structures in various organizations to refocus business [6].Thus, the industry can overcome previously unforeseen situations to survive in a competitive environment.
The success of an industry is often measured using sustainability performance through social, environmental, and economic indicators [7]- [10].In addition, sustainability also serves as a benchmark 1256 (2023) 012001 IOP Publishing doi:10.1088/1755-1315/1256/1/012001 2 for consideration for asset managers in carrying out actions, planning, and a decision to be proposed [10], [11].This illustrates that industrial activities that produce a product's economic value also impact society and the safety and health of the surrounding environment.Thus, compliance in asset maintenance, production processes, and manufacturing processes during operations must always be controlled to reduce the impact of industry on the economy, society, and the surrounding environment [8].
Based on the results of an empirical study on one of the manufacturing companies in Indonesia, it is known that in the company's long-term plan for 2020-2024, it has planned to make organizational changes [12].Based on the asset database until 2022, the company has 1,287 types of physical assets managed by asset managers, and as many as 527 units, or around 41% of the total 1,287 units of existing production machine type assets, are welding machine type assets used for production activities (production assets).However, the utilization of each of the company's assets has also shifted, moving to subsidiaries at around 75%, affiliate companies at around 10%, and those managed by the company's asset managers at only around 15%.
The concept of asset management is widely adopted to optimize decision-making in terms of balancing costs, risks, and performance for asset-intensive companies [13], [14].However, changes in the utilization of physical assets between different entities certainly have an impact not only on the life cycle but also on the risk of maintaining sustainable assets.This is to ensure safety, availability, and reliability, as well as the provision of products according to the required quality [8].
Based on the impacts of these organizational changes, it is necessary to evaluate how the company performs through the performance of sustainability assets.Researchers have conducted empirical studies on previous studies.[15] in their research through empirical studies using the case exploration method, retested [16] model of 80 sustainability indicators (43 economic aspect indicators, 20 social aspect indicators, and 17 environmental aspect indicators) as a measure of industrial sustainability performance in the manufacturing industry in Italy and Germany.[8]in their research, assessed the impact of maintenance practices on asset sustainability in manufacturing companies located in the German region by measuring the level of efficiency in environmental, social, and economic aspects.
Researchers need to consider the variables conveyed by [8] in evaluating sustainability assets, namely by evaluating other aspects, such as aspects of the environmental budget level and aspects of the health budget level.In addition, it is necessary to consider long-term business conditions.As stated by [17], dynamic conditions greatly affect the company's operational cycle in decision-making.Refocusing business, which has implications for the delegation of the company's main business process and the utilization of production facility assets to subsidiary companies, impacts the maintenance and management activities of sustainable asset organizations so that it can impact company performance for a certain period.
From the consideration of these empirical studies, no results show performance evaluation of sustainability assets from organizational changes in a company by considering dynamic aspects through the Dynamic Data Envelopment Analysis (DDEA) approach.As [17]- [22], dynamic aspects become important to detect efficiency over certain time spans with the DDEA approach.It is considered important because the conditions of organizational change need to be evaluated before and after organizational change as a consideration in decision-making.Thus, researchers consider it necessary to deepen the aspects of sustainability assets that prioritize the evaluation stage of the impact of organizational changes in the company to obtain conclusions that provide benefits, namely by identifying the efficiency of sustainability asset indicators based on DDEA.

Research Method
This research was conducted at one of Indonesia's railway industry manufacturing companies.The problem that is the object of research is the increase in sustainability assets in the implementation of maintenance and the impact of organizational changes.

Data Collection
The data used in this study is sample data in the form of historical data on input and output variables related to improving the performance of sustainability assets in the implementation of maintenance and the impact of organizational changes in the period 2018-2022.The asset transaction data used are the assets of the production facility group for the production process, especially the type of welding machine and sustainability aspects covering economic, social, and environmental aspects.
The determination of the object and period of research is influenced by the reasons for the transaction cycle and methodology, as well as the availability of data that affects the context of the problem.The conditions are described as follows: • The conditions from 2018 to 2022, the Company achieved the highest fluctuations in company performance, marked by sales achievements, increased asset investment, and organizational changes.
• The phenomenon of organizational disruption, which has recently been introduced massively and was subsequently followed by SOEs of the Republic of Indonesia with significant organizational changes, is shown by the use of assets owned by the Company by Subsidiaries.

Data Analysis Methods
This research uses quantitative analysis methods through the DDEA approach related to improving the performance of sustainability assets in the implementation of maintenance against the impact of organizational change.The DDEA method in this study aims to evaluate efficiency in welding machine asset maintenance practice variables through a sustainable indicator approach as input and production amount as output variables in short-term and long-term situations.A measure of efficiency [23], [24], described in the maximum ratio of output weights to input weights provided that the ratio for each Decision-Making Unit (DMU) is less than or equal to one (≤ 1).The formula is explained by [20] as follows: ; Subject to: ,   ≥ 0; →  = 1, … , ; and  = 1, … , Formula (1)(2) above for   ,   is the output and input values to j of the DMU and must be positive.While   ,   ≥ 0 is the weight of the variable that will determine the solution of the problem.The DDEA model in this study uses a model delivered [20], which is input-oriented to minimize input concerning fixed output.Still, adjustments are made to input variables according to the results of identifying sustainability indicators conveyed [8], [15] so that the model used in this study becomes as shown in Figure 1.
In addition, DDEA Model in this study is input-oriented to minimize input.The dynamic system referred to in this study is related to time, as assumed below: 4

Figure 1. DDEA Model in sustainability aspects
Where   ,   and   is multiplication of each output as r, input as i, and carry over to f.This model is an input-oriented model that attempts to minimize input concerning a fixed output.The input-output variable for sustainable assets is the sustainability pillar variable in the economic, social, and environmental Triple Bottom Line (TBL) [25].From the results of identifying the efficiency level of sustainability assets that have been carried out based on the DDEA, an analysis related to slack analysis is carried out.It is to see the potential for slack that occurs in sustainability variables that have been identified.The analysis results identify the level of efficiency and slack analysis, then analyze the input targets on each variable of sustainability assets to see the condition of improving the performance of these sustainability assets.More specifically, observations are made on some sustainability indicators, as in Table 1: Description of operational variable in this research is follows: or defective in the production process compared to the amount of material to be used in the period 2018-2022.• Hazardous waste is a variable input level of toxic and hazardous materials waste generated from production process activities in the period 2018-2022 in percentage (%).• Energy consumption is a variable input level of energy used to carry out production activities and workshop operations in the period 2018-2022 in Rupiah (IDR).• Production Amount is the variable output of the number of train-type products completed by the company from 2018 to 2022.Data processing to obtain useful results in research discussions is done using DEA Frontier application software from http://www.deafrontier.net/.

Assumptions and Limitations of Research
The focus of this research covers several things that are limited to the problem, namely This research uses secondary and primary data on production facility assets in the company, especially welding machine-type assets, in the period 2018-2022.While the scope of assets used as the object of research is welding machine assets whose utilization is carried out by subsidiary companies, which has an impact on efficiency.
The sustainability indicators used in this study depend on the availability of data, so removing some sustainability indicators that have been studied in previous studies tailored to the needs of the company, While the data used in the research is data on the SAP application system, which has the information needed to perform analysis, This makes it possible to state that the resulting conclusions are feasible in terms of the availability of data related to the economic justification of sustainability.

The Result and Discussion
Measurement of efficiency scores using the CCR (Charnes, Cooper, and Rhodes) model through DDEA with input-oriented Constant Return to Scale (CRS) is necessary because the company is in a manufacturing industry that has job order and customization business characteristics, so improving company performance is very dependent on controlling the input of production factors to produce a product.

Identify the efficiency of sustainability asset indicators based on DDEA
Based on the identification of sustainability asset indicators described earlier, a collective of all aspects of output and input variables, both in economic, social, and environmental aspects, is presented in detail in Table 2.
From the results of data identification in Table 2, data processing was carried out using the Frontier Analyst application to identify the efficiency score of sustainability asset indicators through DDEA.The results of such identification are presented in Table 3.After identifying the efficiency of sustainability asset indicators based on DDEA, slack analysis is carried out on sustainability asset input indicators.Slack analysis of inputs is used to determine the amount of input proportionally so that DMU can reach the minimum point of efficiency.Based on the analysis of slack inputs on sustainability asset indicators, it is known that there are variables with slack input values that have yet to reach the minimum efficiency point target.The results of the slack analysis are presented in Table 4.
From the slack analysis, it is known that in DMU 4, DMU 7, and DMU 8 there is an excess proportion that has an impact on inefficiencies, so it is necessary to reduce the number of inputs with constant output targets to achieve maximum efficiency targets.The results of the input target analysis are presented in Table 5.

Analysis of economic aspects and policy implications
The concept is built for companies operating a pool of assets Table high complexity to reduce risk and maximize return on investment must make maintenance strategy a vital issue and invest appropriately in the area [26].However, based on the results of the analysis of the economic aspects of the efficiency score of sustainability asset performance as in Table 4, it is known that before the organizational change, inefficiencies were found in maintenance costs of IDR 50,726 million with an availability level of 0,993 (less than 100%).In addition, the level of material consumption to produce railway products also experienced inefficiencies of 41.281,306pcs.Compared to the In addition, from the analysis of target inputs and slack inputs in Tables 4 and 5, it is known that conditions after organizational changes experience inefficiencies that are less optimal than before, followed by differences in management in the asset maintenance function of welding machines.

Analysis of social aspects and policy implications
Based on Table 4, it is known that during the period of semester 1 of 2018 to semester 1 of 2019, before organizational changes occurred, social aspects had reached optimal efficiency points with a score equal to 1 (one); however, in semester 2 of 2019 before organizational changes, there was excess use of inputs to output with an efficiency score of less than 1 (<1).These advantages are sequentially at the level of environmental impact costs of IDR 19,605 million, health costs of IDR 369,997 million, and the percentage rate of work accidents of 0.107.Meanwhile, after organizational changes throughout 2021, there was excess use of inputs in environmental impact costs of IDR 26,278 million and employee health costs of IDR 125,405 million, and there were still work accidents.From these conditions, based on Table 5, to achieve optimal efficiency in the period before organizational changes, especially social aspects in semester 2 of 2019, the environmental impact cost from previously amounting to IDR 220,392 million must reach a minimum point of IDR 41,804 million, and employee health costs from the previous IDR 1,749 million per employee must earn a minimum threshold of IDR 117,226 million and an accident percentage rate of 0.053, for fixed output conditions.Meanwhile, to achieve optimal efficiency in the period after organizational changes in semester 1 of 2021, the environmental impact cost from the previous IDR 99,157 million must reach a minimum point of IDR 35,524 million; employee health costs from the previous IDR 799 thousand per employee must achieve a minimum threshold of IDR 372,339 thousand; and the percentage of accident incidence from the last 0.143 must reach a minimum point of 0.089 for fixed output conditions.In Semester 2 of 2021, environmental impact costs from the previous IDR 437,368 million must achieve a minimum threshold of IDR 12,602 million; employee health costs from the previous IDR 621 thousand per employee must reach a minimum point of IDR 114,899 thousand; and the percentage of accident incidence from the last 0.857 must achieve a minimum threshold of for fixed output conditions.

Analysis of environmental aspects and policy implications
Table 4 shows that before the organizational change, environmental aspects were mainly at the optimal point of efficiency with an efficiency score equal to 1 (one), except in the 2nd semester of 2019 when the cost of energy consumption levels exceeded IDR 652,535 million.Meanwhile, conditions after organizational changes throughout 2021 experienced excess use of inputs.In Semester 1 of 2021, the percentage of defective material in the production process (reject) was 0.030, the rate of hazardous waste was 0.307, and the cost of energy consumption was IDR 849.378 million.Meanwhile, for semester 2 of 2021, the percentage of defective material in the production process (reject) is 0.007, the rate of hazardous waste is 0.025, and the cost of energy consumption is IDR 295,052 million.
Based on these conditions, based on Table 5, to achieve optimal efficiency in the period before organizational changes, especially in environmental aspects, the cost of energy consumption level in semester 2 of 2019 from the previous IDR 6,696 million must reach a minimum point of IDR 1,213,112 million.Meanwhile, to achieve the optimal level of efficiency in the period after organizational changes in semester 1 of 2021, the percentage of defective material levels in the production process from the previous 0.052341 must reach a minimum point of 0.003, the rate of hazardous waste from the last 0.659 must achieve a minimum point of 0.104, and the level of energy consumption costs from the previous IDR 3,151 million must reach a minimum threshold of 1,114,299 million.In Semester 2 of 2021, the percentage of defective material levels in the production process from the previous 0.040573 must achieve a minimum point of 0.001.The hazardous waste rate from the last 0.341 must reach a minimum threshold of 0.038.The energy consumption costs from the previous IDR 3,705 million must achieve a minimum point of IDR 390,024 million.
Based on the results of the analysis above, conditions before and after organizational changes, especially in electrical energy consumption, we experienced excess input even though the company already had policies and programs in environmental and energy management.It is followed by the absence of a company program to improve the culture of controlling electrical power for each employee comprehensively, to reduce the company's fixed costs, and provide positive performance in the long run.

Conclusion
Based on the results of data processing and data analysis described earlier, it can be concluded as follows: From the results of the analysis through the Dynamic Data Envelopment Analysis method approach, it is known that the level of efficiency of sustainability asset indicators on the impact of organizational change found in DMU 1, DMU 2, DMU 3, DMU 5, DMU 6, DMU 9, and DMU 10 has shown the achievement of constant or efficient conditions with input-oriented CRS efficiency equal to 1 (DMU = 1).While DMU 4, DMU 7, and DMU 8 show increasing conditions or need to be improved, inputoriented CRS efficiency is at < 1.However, this shows that both before and after organizational changes do not significantly impact the efficiency score of sustainability assets, as seen by the condition of inefficiencies in DMU 4, which was before the organizational change.However, the conditions in question are still better than before the organizational changes.
Based on the results is known that efficiency increases to reach optimal points in DMUs that experience inefficiency conditions, namely: first, DMU 4 to reach the minimum input point, in maintenance costs, increased efficiency score 77% from Rp1065,106 million, amount of material consumption increased efficiency score 86% from 42482,213pcs/WI, environmental impact costs increased efficiency score 81% from Rp220,392 million, employee health costs increased 93% or Rp117,226 thousand per employee, percentage rate of accidents increased efficiency score 91% from 8 events, dangerous waste level increased efficiency score 72% from 9,570kg and cost energy consumption rate increased efficiency score 82% from Rp1,213,112 million at fixed output.
Second, DMU 7 to reach the minimum input point, the maintenance cost increased efficiency score 51% from Rp174,856 million, the amount of material consumption increased efficiency score 38% from 17,874,875 pcs/wi material, environmental impact cost increased efficiency score 81% from Rp35524 million, employee health costs increased efficiency score 53% from Rp372,339 thousand, percentage accident incidence increased efficiency score 38% from 1 incident, percentage of defective material level in production process increased efficiency score of 94% from 1,584pcs/wi, ratio of hazardous waste increased efficiency score of 84% from 5,102kg and energy consumption cost rate increased efficiency score of 65% from Rp1,114.3 million at fixed output.
Third, DMU 8 to reach the minimum input point, the maintenance cost increased efficiency score by 90% from Rp64,184 million, environmental impact costs increased the efficiency score by 97% from Rp12,602 million, employee health costs increased the efficiency score 81% from Rp114,899 thousand per employee, the percentage of accident incidence increased efficiency score 97% from 6 events, for the rate of defective material levels in the production process increased efficiency score 98% from 1.713pcs/wi, the percentage of hazardous waste increased efficiency score by 89% from 2,643kg and the level of energy consumption cost increased efficiency score by 89% from Rp390,024 million at fixed output.
This research still has things that are lacking to be material for future studies to be refined for future researchers, so it is recommended that, from the condition of organizational changes that have an inefficiency impact on sustainability asset indicators, it is necessary to further evaluate the effectiveness of the company's asset management function, especially in the type of welding machine, and improve the culture in controlling electrical energy for each employee comprehensively, to reduce the company's fixed costs and provide positive performance in the long term.Further research can be carried out in more depth by adding risk analysis to provide mitigation solutions for the impact of corporate organizational change policies.Adding data and research objects to see further comparisons between similar companies will give a better picture of sustainability assets in the existing manufacturing industry.

Table 1 .
Variable units of research input and output in the period 2018-2022, obtained from the company's financial statements contained in the application system in Rupiah (IDR).• Availability is the percentage (%) input variable of the comparison between available time reduced by downtime divided by the time available on the welding machine in the time range from 2018 to 2022.• Material Consumption is an input variable for the use of raw materials based on the working instruction report, namely per pcs component/Working Instruction (pcs/WI) in the period 2018 to 2022.• Environmental Impact is an input variable of the amount of budget value of cost realization for the allocation of activities on environmental impacts in the period 2018-2022 in Rupiah (IDR).• Costs of health are variable inputs to the amount of budget value realized for the allocation of employee health per employee in the period 2018-2022 in Rupiah (IDR).• Incident & Accident is an input variable of events caused by activities on company assets from 2018 to 2022.• Material Reject is an input variable percentage ratio (%) of the number of raw materials rejected • Costs of Maintenance are variable inputs: the number of accumulated costs of maintenance activities covering preventive and corrective maintenance activities on welding machine assets

Table 2 .
Sustainability asset indicator identification data based on DDEA

Table 3 .
Results of identification of efficiency indicators of sustainability assets based on DDEA

Table 4 .
The Results of slack analysis of sustainability asset indicators based on DDEA for 2018 -2022 Table of organizational change, the inefficiency of welding machines maintenance costs in 2021 is IDR 47,726 million in semester 1 of 2021 and IDR 58,532 million in semester 2 of 2021.It is also shown that the availability rate of welding machines for production activities throughout 2021 did not reach 100% (semester 1 of 2021 was 0.988, and semester 2 of 2021 was 0.971).Based on Table 5, to achieve optimal efficiency in maintenance costs before organizational changes in semester 2 of 2019, from the previous IDR 1065,106 million, it must reach the minimum point of IDR 246,047 million at fixed output.Meanwhile, for conditions after organizational changes from the previous IDR 355,961 million (semester 1 of 2021) and IDR 663,647 million (semester 2 of 2021), it must reach the minimum point of IDR 47,005 million and IDR 58,532 million at fixed output.

Table 5 .
The Results of the analysis of input targets for sustainability asset indicators based on DDEA for the period 2018 -2022