Papers by Zakka Ugih Rizqi
Engineering applications of artificial intelligence, Aug 1, 2024
Social Science Research Network, Dec 31, 2022
Computers & industrial engineering, Mar 1, 2024
Applied Energy
Reducing global warming is crucial for sustainability. Carbon emissions primarily stem from energ... more Reducing global warming is crucial for sustainability. Carbon emissions primarily stem from energy supply, prompting a shift from Non-Renewable Energy Supply (NRES) to Renewable Energy Supply (RES). However, transitioning to RES entails substantial investment and faces supply uncertainty due to weather dependency. Therefore, the transition should be done gradually, requiring a reliable approach to energy mix modeling. This study proposes a System Dynamics framework integrated with Adaptive Particle Swarm Optimization (APSO) and Machine Learning to optimize the energy mix under supply uncertainty. Due to energy system dynamicity, the proposed framework considers not only supply, but also demand, energy storage, electric vehicle, and emission subsystems. The experiment has been conducted by taking the United States as a case under various scenarios namely to minimize the total system cost, total carbon emissions, and both, accounting for the static and dynamic cost of RES. Results of this study reveal four main points: (i) A 38% reduction in total system cost is achievable by decreasing the RES Ratio to 6%, but total emissions will rise by 8%; (ii) A 55% reduction in total emissions is possible by directly transitioning to 100% RES, but total system cost increases by 68%; (iii) Both objective functions can be significantly minimized at a time by increasing the RES ratio; (iv) Dynamic cost offers a better opportunity for reducing costs and emissions than static cost.
IOP Conference Series: Materials Science and Engineering, 2020
Increasingly developing technology makes human easier to carry out the life, and one of them is i... more Increasingly developing technology makes human easier to carry out the life, and one of them is in the transportation sector. The high number of vehicle accidents causes losses to the passenger so that it requires safeguards to minimize these losses, one of the ways is by using a seat belt. This study aims to design a voice of customer-based seat belt using integrating Kano model and Quality Function Deployment (QFD) produced by an innovative product, namely “Multifunctional Seat Belt for Vehicle Safety”. Through the distribution of questionnaires, 8 attributes are needed in the design of the seat belt. The results of the Kano Model analysis show that 2 attributes fall into the indifferent category which is then eliminated because the presence or absence of these attributes does not affect customer satisfaction. The other 6 attributes are portable, can store items, can hold the body while sleeping, can warm the body, there are pads on the sides of the head, and adjustable strap. The...
IOP Conference Series: Materials Science and Engineering, 2020
In inventory management, stockout and overstock are problems that always occur in the inventory s... more In inventory management, stockout and overstock are problems that always occur in the inventory system. The limitations of the method make it difficult for companies to determine the level of inventory following probabilistic inventory conditions. Ajeng Gallery is a quality bag craft company that has problems in the supply of raw materials where there is always a large stockout and overstock. The research is limited to cow leather material which is the main material based on the results of ABC analysis. This research also integrates Min-Max method which is a deterministic method to determine the level of inventory then the results will be integrated with Monte Carlo simulation which is a probabilistic method so that it can evaluate the amount of stockout and overstock that occurs. The results showed that the company no longer experienced stockout for 1 month and the amount of overstock decreased by 0.42% of the actual system.
IOP Conference Series: Materials Science and Engineering, 2020
The length of supply chain at Ajeng Gallery causes emergence of risks that can harm the company. ... more The length of supply chain at Ajeng Gallery causes emergence of risks that can harm the company. Moreover, the company has not implemented risk management properly so that the purpose of this study is to implement supply chain risk management properly. By using House of Risk, it is obtained 10 risk events and 9 risk agents. 2 risk agents that have the largest percentage are mitigated. There are 4 priority mitigation strategies to overcome risk agents. The implementation of mitigation strategy can reduce risk levels in risk map based on previous research that discusses the same mitigation plan.
Applied Energy, 2023
Reducing global warming is crucial for sustainability. Carbon emissions primarily stem from energ... more Reducing global warming is crucial for sustainability. Carbon emissions primarily stem from energy supply, prompting a shift from Non-Renewable Energy Supply (NRES) to Renewable Energy Supply (RES). However, transitioning to RES entails substantial investment and faces supply uncertainty due to weather dependency. Therefore, the transition should be done gradually, requiring a reliable approach to energy mix modeling. This study proposes a System Dynamics framework integrated with Adaptive Particle Swarm Optimization (APSO) and Machine Learning to optimize the energy mix under supply uncertainty. Due to energy system dynamicity, the proposed framework considers not only supply, but also demand, energy storage, electric vehicle, and emission subsystems. The experiment has been conducted by taking the United States as a case under various scenarios namely to minimize the total system cost, total carbon emissions, and both, accounting for the static and dynamic cost of RES. Results of this study reveal four main points: (i) A 38% reduction in total system cost is achievable by decreasing the RES Ratio to 6%, but total emissions will rise by 8%; (ii) A 55% reduction in total emissions is possible by directly transitioning to 100% RES, but total system cost increases by 68%; (iii) Both objective functions can be significantly minimized at a time by increasing the RES ratio; (iv) Dynamic cost offers a better opportunity for reducing costs and emissions than static cost.
PLOS ONE
The COVID-19 pandemic has presented significant public health and economic challenges worldwide. ... more The COVID-19 pandemic has presented significant public health and economic challenges worldwide. Various health and non-pharmaceutical policies have been adopted by different countries to control the spread of the virus. To shed light on the impact of vaccination and social mobilization policies during this wide-ranging crisis, this paper applies a system dynamics analysis on the effectiveness of these two types of policies on pandemic containment and the economy in the United States. Based on the simulation of different policy scenarios, the findings are expected to help decisions and mitigation efforts throughout this pandemic and beyond.
OISAA Journal of Indonesia Emas, 2020
E-commerce is growing rapidly in Indonesia. In fact, the number of e-commerce transactions in Ind... more E-commerce is growing rapidly in Indonesia. In fact, the number of e-commerce transactions in Indonesia is the largest in Southeast Asia in 2019. This has a major impact on logistics service providers because the e-commerce trading system requires logistical intermediaries between sellers and buyers. Therefore, logistics companies are developing rapidly to achieve this opportunity so that each company competes to become the best logistics company. Companies become competitive if they have a good business process. So that the effectiveness and efficiency of the supply chain are two important things so that the company becomes sustainable. This research is basically qualitative study where the business process development of PT Z is carried out to enhance the efficiency and effectiveness of the supply chain through Focus Group Discussion (FGD) and Benchmarking. Through a systematic process, more effective and efficient business process are obtained from the perspective of information ...
OISAA Journal of Indonesia Emas, 2020
The local language is one of the cultural properties that must be maintained. However, modernizat... more The local language is one of the cultural properties that must be maintained. However, modernization can not be avoided and it causes the young generation to do not care about their own local language anymore. In Indonesia, there are already 11 extinct local languages. If there is no action to take care, it will increase the number of local language extinction. The Javanese language is one of local languages that is the most speakers in Indonesia, especially in Yogyakarta as the student city. However, the Javanese language itself is started to be left alone by the young generation. Therefore, this research is intended to give the scientific written idea to maintain Javanese language in Yogyakarta. This research is done by 2 steps of research, the first step is finding the idea by observation, literature study, and Focus Group Discussion with 3 experts. Second, prioritizing ideas to be realized using AHP with multi-expert. The result shows that there are 3 ideas that have to be reali...
Indonesian Scholars Scientific Summit Taiwan Proceeding, 2021
Forecasting and aggregate planning are crucial phases in production planning especially for oil r... more Forecasting and aggregate planning are crucial phases in production planning especially for oil refining company that takes expensive production cost. Accurate forecasting greatly influences the success of production planning since it is the starting point of production planning. Whereas aggregate planning becomes important because it functions to bridge between the demand or production target with the existing resource requirements. Seeing the importance of accurate forecasting and aggregate planning, this research emphasizes the use of Fuzzy Time Series (FTS) Algorithm to forecast Premium sales in Indonesia’s oil refining company. The comparison is also done between FTS with the other classical techniques in time series forecasting to test the reliability of algorithm and FTS outperforms the others based on the lowest MAPE value as much as 0.87%. FTS result is then used as an input in the aggregate planning by using heuristics method and comparing 3 strategies which are Level Str...
Inventory is one of the main components in supply chain. However, it is not easy to design invent... more Inventory is one of the main components in supply chain. However, it is not easy to design inventory policy under uncertainties. The frequent occurrence of overstocks increases the company's financial expenditure. Otherwise, stockout decreases customer satisfaction and damage the company's image. This study aims to provide monte carlo model to design inventory policy with the aim of maximizing net income with a variety of uncertainties, one of the uncertainties is defective product because of the travel from suppliers. To handle the complexity and uncertainty of problem, a Monte Carlo simulation is used with spreadsheet-based representation. To test the reliability of the model, guitar company is used as relevant use case with uncertainty adhered ‘the greater number of order quantity, the greater likely the defective guitar will be’. The verification & validation process, experimental design, and alternative selection are also done with statistical tests. Based on the simula...
Semakin tingginya tingkat persaingan bisnis di Indonesia menuntut setiap perusahaan untuk selalu ... more Semakin tingginya tingkat persaingan bisnis di Indonesia menuntut setiap perusahaan untuk selalu berkembang. UD Jati Surya merupakan UKM produsen furnitur di Yogyakarta yang ingin mengembangkan bisnisnya. Ditambah semakin banyaknya kompetitor dibidang yang sama sehingga menuntut perusahaan untuk mempertahankan keberadaannya bahkan meningkatkan perkembangan dari bisnisnya. Penelitian ini menggunakan analisis SWOT untuk menentukan strategi-strategi bisnis yang tepat dengan melihat sisi kekuatan, kelemahan, kesempatan dan ancaman yang dimiliki oleh UD Jati Surya. Strategi-strategi yang didapat kemudian dilakukan pembobotan menggunakan Analytical Hirarchy Process (AHP) guna mendapatkan strategi mana yang paling tinggi prioritasnya berdasarkan pandangan expert. Kemudian akan digambarkan model bisnisnya dengan metode Business Model Canvas (BMC). Hasil penelitian menunjukkan didapat 5 strategi berdasarkan analisis SWOT. Kemudian dilakukan pembobotan didapat strategi yang memiliki prioritas tertinggi adalah meningkatkan produksi yang selalu sesuai dengan pesanan pada momen (musim) pembelian masyarakat dan memanfaatkan tenaga kerja yang tersedia. Kemudian memvisualisasikan bisnis UD Jati Surya berdasarkan sembilan elemen yang ada, yaitu Customer Relationships, Key Partners, Value Propositions, Customer Segments, Channel, Revenue Stream, Key Resource, Key Activities dan Cost Structure.
Transformasi: Jurnal Pengabdian Masyarakat
Desa Rejosari adalah salah satu Desa di Kabupaten Purworejo, Jawa Tengah yang memiliki potensi su... more Desa Rejosari adalah salah satu Desa di Kabupaten Purworejo, Jawa Tengah yang memiliki potensi sumber daya alam (SDA) berupa pohon kelapa. Akan tetapi, pemanfaatan yang tidak maksimal sering mengakibatkan pembuangan kelapa disebabkan jumlah panen yang berlebih. Untuk mengoptimalkan pemanfaatan SDA tersebut, dilakukan perancangan bisnis produksi Virgin Coconut Oil (VCO). Pengabdian ini fokus pada aspek teknis yang meliputi pemilihan lokasi produksi dengan metode Analytical Hierarchy Process (AHP), analisis aliran produksi VCO, layout design, dan penentuan jumlah pekerja dan peralatan yang optimal berbasis simulasi. Hasil pemilihan lokasi produksi pada program pengabdian ini menunjukkan bahwa lokasi yang terletak di samping SMK VIP Maarif NU 1 Kemiri merupakan lokasi yang paling optimal dilihat dari kriteria kemudahan akses, luas bangunan, dan ketersediaan sarana dan prasarana. Kemudian untuk memenuhi permintaan selama 4 bulan ke depan, diperlukan 13 orang pekerja beserta peralatan yang mendukung proses produksi dengan investasi serendah mungkin. Selanjutnya layout dari lantai produksi VCO dirancang dengan pertimbangan dapat menghasilkan jarak seminimal mungkin sehingga mampu meningkatkan efisiensi serta mempermudah jalan keluar-masuk barang. Hasil analisis teknis kemudian disimulasikan menggunakan software Flexsim versi 2021 dan menunjukkan bahwa perancangan bisnis VCO telah mencapai hasil efektif dilihat dari ketercapaian output produksi dan efisien dilihat dari utilisasi pekerja. Uji coba produksi serta penyuluhan telah dilakukan sebagai bukti validasi.
OISAA Journal, 2020
The local language is one of the cultural properties that must be maintained. However, modernizat... more The local language is one of the cultural properties that must be maintained. However, modernization can not be avoided and it causes the young generation to do not care about their own local language anymore. In Indonesia, there are already 11 extinct local languages. If there is no action to take care, it will increase the number of local language extinction. The Javanese language is one of local languages that is the most speakers in Indonesia, especially in Yogyakarta as the student city. However, the Javanese language itself is started to be left alone by the young generation. Therefore, this research is intended to give the scientific written idea to maintain Javanese language in Yogyakarta. This research is done by 2 steps of research, the first step is finding the idea by observation, literature study, and Focus Group Discussion with 3 experts. Second, prioritizing ideas to be realized using AHP with multi-expert. The result shows that there are 3 ideas that have to be realized sequentially. The first idea to be applied is 'One day with Javanese language program', second is the making of 'Java café', and the third is the selection of 'Javanese language ambassador'.
OISAA Journal, 2020
E-commerce is growing rapidly in Indonesia. In fact, the number of e-commerce transactions in Ind... more E-commerce is growing rapidly in Indonesia. In fact, the number of e-commerce transactions in Indonesia is the largest in Southeast Asia in 2019. This has a major impact on logistics service providers because the e-commerce trading system requires logistical intermediaries between sellers and buyers. Therefore, logistics companies are developing rapidly to achieve this opportunity so that each company competes to become the best logistics company. Companies become competitive if they have a good business process. So that the effectiveness and efficiency of the supply chain are two important things so that the company becomes sustainable. This research is basically qualitative study where the business process development of PT Z is carried out to enhance the efficiency and effectiveness of the supply chain through Focus Group Discussion (FGD) and Benchmarking. Through a systematic process, more effective and efficient business process are obtained from the perspective of information flow, financial flow, and flow of goods.
Indonesian Scholars Scientific Summit Taiwan Proceeding, 2021
Inventory is one of the main components in supply chain. However, it is not easy to design invent... more Inventory is one of the main components in supply chain. However, it is not easy to design inventory policy under uncertainties. The frequent occurrence of overstocks increases the company's financial expenditure. Otherwise, stockout decreases customer satisfaction and damage the company's image. This study aims to provide monte carlo model to design inventory policy with the aim of maximizing net income with a variety of uncertainties, one of the uncertainties is defective product because of the travel from suppliers. To handle the complexity and uncertainty of problem, a Monte Carlo simulation is used with spreadsheetbased representation. To test the reliability of the model, guitar company is used as relevant use case with uncertainty adhered 'the greater number of order quantity, the greater likely the defective guitar will be'. The verification & validation process, experimental design, and alternative selection are also done with statistical tests. Based on the simulation result, it is known that changing the reorder point to 80 and the order quantity to 90 gives the best result which can increase net income by 0.44% compared to the initial net income. In addition, the number of stockouts has decreased.
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Papers by Zakka Ugih Rizqi