Jurnal Ilmu Komputer dan Teknologi Informasi

Analisis Pola Pembelian Menu Coffee Shop Menggunakan Algoritma FP-Growth sebagai Dasar Rekomendasi Menu pada Sistem Kasir

Martianova Lusia Sihombing — 2026-09-28

Transaction data in cash register systems has the potential to serve not only as sales records but also to identify customer purchasing patterns that can support business decision-making. Unfortunately, the utilization of transaction data in coffee shops is often limited to sales reports, resulting in suboptimal use of the relationships between menu items. This study aims to analyze menu purchasing patterns using the Frequent Pattern Growth (FP-Growth) algorithm and to interpret the resulting association rules as a basis for menu recommendations in the cash register system. Employing a quantitative approach and descriptive methods, this research analyzes the public dataset The Bread Basket, which contains over 9,000 transactions. Data preprocessing was conducted using RapidMiner Studio through attribute selection and transformation stages. The FP-Growth algorithm was applied with a minimum support parameter of 5% and a minimum confidence of 20%, yielding two association rules: Bread → Coffee and Cake → Coffee. The Cake → Coffee rule demonstrates a positive relationship with a support value of 0.055 and confidence of 0.527, while Bread → Coffee does not indicate a positive association despite having a higher support value. These findings suggest that the FP-Growth algorithm is effective in identifying purchasing patterns that support menu recommendation logic.

Audit Retrospektif Kinerja Chiller Tanpa Bas: Validasi Data Ultrasonik Portabel Dan Deteksi Anomali Yang Dapat Dijelaskan

Aldi Cahya Muhammad — 2026-08-28

Chillers in government buildings located in tropical climates often operate without a building automation system (BAS), making performance degradation difficult to detect through routine monitoring. This study reanalyzes the 2024 field measurement dataset for a 500 TR (R134a) water-cooled centrifugal chiller in a city government office without new data collection. The Isolation Forest model interpreted with permutation-based SHAP attribution marks instances of zero flow rate and surrounding reading changes, with residuals against local trends as the primary explanatory feature. Extended flatline segments following zero events are overlooked, complementing rather than replacing manual screening. The marking proportion ranges from 6.2% to 6.5% per session, adhering to a contamination parameter of 0.06. Pipe cross-section examinations restore stable diameters at three locations: 240 mm, 97.7 mm, and 450 mm, correcting a labeling error. Recalculated results show evaporator heat of 825.5 ± 79.7 kW and an actual COP of 3.75 ± 0.36 compared to a design COP of 5.76 at a measured load of 47.2% capacity. The energy balance deviation reaches 11.6%, exceeding the 5% threshold. This imbalance reflects combined uncertainty, with specific power at 0.94 kW/TR and a temperature difference of 1.3 °C, consistent with additional thermal resistance yet to be verified.