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Study on Increasing the Cracking Resistance of Unsaturated Polyester Composites with MMA and Rice Husk Fiber Reinforcement
Get PDFThe development of polymer composite materials has been widely developed as an alternative material to replace metal materials due to various advantages such as having relatively good mechanical strength, low density, and easy manufacturing process, but polymers have many disadvantages that they easily crack when impacted. One of the most widely used materials for composite matrices is unsaturated polyester polymers which are widely used in vehicle, aircraft, and ship hull components as well as vehicle components. The crack study is important because it causes the material to no longer be able to support loads below its yield strength, therefore causing failure to occur more quickly. One way to overcome material failure due to cracks in composite materials is to prevent crack propagation by adding reinforcing materials. In this study, a composite material was made using rice husk fiber to increase the crack resistance of the polyester composite matrix. From the results of the crack test, it is known that there is a tendency to increase the percentage variable of the addition of rice husk by 5%, 10%, 15%, and 20%. The expected value obtained to determine the crack resistance of the material is the value of the stress intensity factor (K1c). The highest K1c price was obtained at a 15% rice husk percentage variable of 1.558 MPa.m0.5, this price could increase the price of the pure polyester stress intensity factor (K1c) by 0.667 MPa.m0.5, indicating an increase of 233.58%
Metode Pemantauan Pekerjaan Konstruksi Menggunakan Point Clouds Berbasis Drone dan LiDAR Iphone
Get PDFKepentingan industri konstruksi untuk informasi yang tepat waktu dan akurat tentang kemajuan proyek konstruksi semakin meningkat. Informasi yang diperlukan untuk mengukur progres proyek konstruksi tidak dapat dengan mudah dikumpulkan dikarenakan terus berubah. Pada sebagian besar lokasi proyek konstruksi, perolehan data bergantung pada pencatatan informasi secara manual di atas kertas, penggunaan foto dan dokumen yang menyebabkan banyak kendala dalam ruang dan waktu. Penelitian ini mengusulkan pemantauan pekerjaan berbasis BIM menggunakan foto udara Drone dan LiDAR Iphone yang diproses menjadi point clouds. Data point clouds berbasis LiDAR Iphone memenuhi persyaratan General Service Administration (GSA) untuk proyek desain arsitektural dengan kesalahan rata-rata dimensi 0,011 m. Data pengamatan terakhir menunjukkan proyek mengalami keterlambatan sebesar 240,10 m3, data ini memungkinkan manajer proyek untuk menilai kemajuan dan mengelola proyek secara komprehensif. Visualisasi 4 dimensi memudahkan manajer proyek untuk mengambil keputusan dengan cepat berdasar informasi aktual sehingga dapat mengurangi waktu pekerjaan dan pembengkakan biaya
Analisis Kerentanan Banjir Menggunakan Data Citra Satelit dan Machine Learning di Kota Surabaya
Get PDFBanjir merupakan bencana alam yang biasanya terjadi saat hujan. Banjir berdampak pada kerusakan sehingga diperlukannya penilaian kerentanan banjir yang efisien. Citra satelit dapat digunakan untuk membantu mendeteksi banjir dalam skala yang luas. Salah satu tantangan dalam mengolah data citra adalah interpretasi citra. Dengan memanfaatkan kemampuan Machine Learning yang diintegrasikan dengan Sistem Informasi Geografis, interpretasi citra dapat dilakukan dengan cepat. Namun, tantangan dari penggunaan citra satelit adalah kurangnya dataset kejadian banjir dalam skala besar. Pada paper ini, kami menyajikan tiga pendekatan Machine Learning, yaitu Bayes, Rain Forest (RF), dan Support Vector Machine (SVM) yang kemudian dianalisis menggunakan metode Frequency Ratio sehingga didapatkan indeks kerentanan banjir. Dengan memanfaatkan citra Sentinel-1 yang tersedia, analisis dalam penelitian ini menunjukkan bahwa Kota Surabaya termasuk kerentanan banjir rendah sebesar 61,23 persen dari total luas wilayah
Purification of lactic acid using alkaline precipitation followed by reactive distillation
Get PDFLactic acid (LA) can be applied commercially in the biodegradable polymer industry. The production of PLA biopolymers requires lactic acid with pure isomers as its raw material, therefore the process of producing lactic acid through biological fermentation pathways is preferred over through chemical synthesis processes that produce mixed (racemic) lactic acid. In general, lactic acid purification process is carried out by several methods including precipitation and distillation. Precipitation is a conventional method for separating fermented lactic acid which is carried out through 2 stages, namely neutralization and acidification. In the process of neutralizing the fermented solution, base is added to precipitate specific lactic acid and then an acidification process is carried out by adding acid to take back the precipitated lactic acid. Distillation of a raw fermented mixture can produce very pure LA. This is an effective method for separating LA from other organic acids. The reactive distillation process is a chemical process in which the chemical reaction and the distillation process are carried out in one unit. In reactive distillation, LA forms esters with alcohols in the presence of an acid catalyst. Esters have much lower boiling points than LA. Therefore, separation can be achieved by distillation. In this research, the lactic acid purification process was carried out by combining the precipitation process followed by the distillation process. The lactic acid solution obtained from the precipitation process is then mixed with ethanol and the catalyst is put into the batch distillation column system. Most of the ethanol and water come out as distillate while the residue is fed back into the distillation column system and aqueous lactic acid solution is added for the hydrolysis stage. The distillate products are ethanol and water, while lactic acid is obtained from the residue. In the esterification step, the concentration of ethyl lactate in the residue was measured, while in the hydraulic stage, the level of lactic acid in the residue was measured. In this study, the results of purification of lactic acid from the bases Ca(OH)2, NaOH, and KOH were obtained sequentially, including: 89.07%; 84.21; and 80.56%. The use of Ca(OH)2 base produces higher purity due to higher cation valence and low solubility formed between Ca(OH)2 and lactic acid so that the amount of lactic acid precipitated is greater than the other bases
Peramalan Curah Hujan di Kota Bandung dengan Metode SARIMA (Seasonal Autoregressive Integrated Moving Average)
Get PDFThe need for future rainfall information, modeling and forecasting is important. The forecasting method is a method used to predict future conditions based on past data. Rainfall data is time-series data in the form of seasonality, a pattern that repeats at fixed time intervals, so the authors use the Seasonal Autoregressive Integrated Moving Average (SARIMA) method, which is appropriate for data with seasonal characteristics. The author takes monthly rainfall data in Bandung city for the period January 2016 to December 2021 to forecast rainfall in Bandung city for next year. After calculations using the SARIMA method, the best model for forecasting rainfall in the city of Bandung is then obtained, namely the SARIMA model (0,0,0)(0,1,1)12
Aplikasi Model ARIMAX dengan Efek Variasi Kalender untuk Peramalan Trend Pencarian Kata Kunci “Zalora” pada Data Google Trends
Get PDFARIMAX is a method in time series analysis that is used to model an event by adding exogenous variables as additional information. Currently, the ARIMAX model can be applied to time series data that has calendar variation effects. In short, calendar variations occur due to changes in the composition of the calendar. The purpose of this study is to apply the ARIMAX model with the effects of calendar variations to forecast search trends for the keyword "Zalora". Data were collected starting from January 2018 to November 2022 in the form of a weekly series. Based on the results of the analysis, the ARIMAX model is obtained with calendar variation effects with ARIMA residuals (1,1,1). Forecasting accuracy using the Mean Absolute Percentage Error (MAPE) of 10.47%. Forecasting results for the next 24 periods tend to fluctuate and it is estimated that in April 2023 there will be an increase in search trends for the keyword "Zalora"
Pengaruh Operasional Bus Sarana Angkutan Umum Massal (SAUM) Penurunan Kemacetan di Kota Balikpapan
Get PDFImplementing bus as a public transport system could reduce traffic congestion on urban roads. This study aims to identify the effectiveness of Sarana Angkutan Umum Massal (SAUM) bus in congestion reduction in Balikpapan. This study uses a macroscopic approach to analyze the changing in traffic characteristics when SAUM buses operate. Modal shift percentage is gained from the previous study. The focus of traffic characteristics is the degree of saturation, operational speed, and travel time. The result shows that decreasing the degree of saturation, increasing operational speed, and shorter travel time occurred. However, the result also found that operating buses do not contribute significantly to increasing operational speed on low-traffic corridors
Pra Desain Pabrik Fenol dari Tandan Kosong Kelapa Sawit
Get PDFFenol merupakan senyawa kimia dengan rumus molekul C6H6O. Tandan Kosong Kelapa Sawit (TKKS) merupakan limbah terbesar dari pabrik yang menggunakan kelapa sawit sebagai bahan utamanya yaitu sekitar 23% dari jumlah tandan buah segar, sehingga sampai saat ini masih sangat melimpah. Komponen utama TKKS yaitu lignin, selulosa, dan hemiselulosa. Lignin inilah yang akan dimanfaatkan sebagai bahan pembuatan fenol. Metode yang dipilih adalah proses pirolisi. Proses produksi fenol dari TKKS terbagi menjadi tiga bagian yaitu proses pre-treatment, proses utama (pirolisis), dan juga proses pemurnian fenol. Proses pre-treatment dibagi menjadi dua tahap yaitu proses grinding dan proses hidrolisis. Proses selanjutnya yaitu proses pirolisis dilakukan pada fluidized bed reactor dengan pemanasan menggunakan N2. Setelah itu, proses pemurnian fenol terbagi menjadi dua proses yaitu proses ekstraksi dan proses distilasi. Kemudian, ditetapkan untuk kapasitas pabrik fenol sebesar 30.000 ton/tahun. Pabrik fenol dari TKKS akan didirikan di Kota Dumai, Provinsi Riau. Penentuan lokasi ini didasarkan pada pabrik yang dekat dengan produsen bahan baku, dekat dengan Ibukota Provinsi Riau yaitu Kota Pekanbaru, dan juga ketersediaan tenaga kerja yang mencukupi. Dengan didirikannya pabrik fenol dari TKKS ini diharapkan mampu menyerap tenaga kerja untuk membantu mengurangi tingkat pengangguran di Kota Dumai, Provinsi Riau. Pabrik direncanakan mulai dibangun pada tahun 2022 dan mulai beroperasi pada tahun 2025. Investasi pembangunan pabrik berasal dari modal sendiri (equity) dan modal pinjaman bank (loan) dengan laju inflasi 1,75% pertahun dan suku bunga bank 8% pertahun. Total biaya bahan baku sebesar Rp 326.068.953.366 pertahun. Untuk Internal Rate of Return dari pabrik terkait adalah sebesar 29.73% dengan Payout Time selama 5 tahun dan 11 bulan serta nilai Break Even Point sebesar 33,08%. Pabrik ini direncanakan untuk beroperasi dengan proses Semi Batch-Continue 24 jam selama 330 hari per tahun operasi dengan rencana kapasitas produksi sebesar 90 ton/hari
Evaluation Batch Process Scheduling for Single Campaign in FMCG Industry
Get PDFThe Fast-Moving Consumer Goods (FMCG) sector plays a pivotal role in meeting daily consumer requirements. Efficient manufacturing and revenue generation are of paramount importance. The industry adopts a batch-processing approach to maintain adaptability and responsiveness to evolving market needs. A critical element in this process is the evaluation of batch scheduling, especially the batch cycle time of the products, a key factor with a substantial impact on production efficiency and profitability. This research delves deep into the complexities of batch scheduling methods between overlapping batches and parallel units for limiting steps, especially single-product campaigns in terms of its benefit towards production efficiency and company profitability. In the end, it illustrates the consequences of optimal scheduling on production time and income, highlighting the potential for significant improvements or downwards within the applied method through sensitivity analysis, which could give the FMCG industry more careful consideration in strategizing its future planning productio
Developing New Indonesia Circular Economy Indicators: A Lesson Learnt from European Union
Get PDFCircular Economy (CE) right now has been a point of interest among countries in the world as a commitment of the Paris Agreement to solve global environmental problems, which are simultaneously beneficial to economics. However, presently there is no single indicator available that easily be used as a CE standard due to various stresses among the countries. There are different approaches among countries in developing CE indicators, although they are still within the scope of the environmental and economic aspects. CE indicators could be developed based on region covering several countries, government/country level, and company level. Those indicators refer to the region and government policy and market or users of the product and a society where its public area would receive waste that the company might produce. This review will discuss only European Union and Poland, representing regions and countries. A region like the European Union (EU) considers ten indicators for CE, consisting of 21 sub-indicators. These indicators include self-sufficiency in raw materials, procurement for the green public, waste generation, food waste, recycling rate, recovery of specific waste streams, recycled materials to raw materials demand contribution, raw material trade-in, investment, jobs, and gross value-added, patents of secondary and recycling raw materials. While Poland, as a member of the EU, developed 25 CE indicators based on the seven dimensions of the economic point of view, such as economic prosperity, zero waste, innovative, renewable energy- based economy, low carbon, smart economy, and spatially effective economy. Implementing a Comparative Analysis Method that compares one indicator to another, the results show that 6 of 10 indicators belonging to the EU overlap with four indicators of 25 belonging to Poland. Covering all indicators of both regions and countries, thus it would become 29 selected indicators that might be useful for developing Indonesia CE- Indicators, which are presently unavailable yet