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Pengaruh Debit Aliran Air terhadap Efektivitas Pendinginan Evaporatif dengan Cooling Pad Berbahan Sabut Kelapa dan Tapis Lontar
Full text linkKrisis energi dan perubahan iklim meningkatkan konsumsi energi untuk pemanasan, pendinginan, dan ventilasi, dengan sektor ini menyumbang 33% dari konsumsi energi global. Pendinginan udara mencapai 60% dari permintaan listrik musim panas, sehingga konservasi energi penting. Sistem pendinginan evaporatif dengan cooling pad berbahan sabut kelapa dan tapis lontar menjadi solusi yang efektif. Tujuan penelitian ini adalah untuk menganalisis pengaruh variasi debit aliran air pada cooling pad berbahan sabut kelapa dan tapis lontar terhadap efektivitas pendinginan evaporatif. Penelitian ini dilakukan secara eksperimen pada ruang pendingin evaporatif dengan dimensi 2,44 m x 1,22 m x 1,22 m dengan merubah jenis bahan cooling pad dan variasi debit aliran air 5 lpm, 7 lpm, dan 9 lpm. Berdasarkan hasil penelitian variasi debit aliran air memiliki pengaruh terhadap efektivitas pendinginan evaporatif menggunakan cooling pad berbahan sabut kelapa dan tapis lontar. Peningkatan debit air dari 5 lpm hingga 9 lpm menghasilkan penurunan temperatur yang lebih besar di ruang pendingin, terutama di ruang 1 yang dekat cooling pad, dan meningkatkan kelembaban relatif di ruang pendingin. Cooling pad sabut kelapa menunjukkan penurunan temperatur awal di ruang satu dekat cooling pad , sementara tapis lontar memberikan distribusi pendinginan yang lebih merata dan konsisten di ruang 1 maupun ruang 2 yang lebih jauh dari cooling pad sehingga tapis lontar menjadi bahan cooling pad yang memiliki performa yang lebih baik dibandingkan sabut kelapa
Pengaruh Jumlah Partikel SiC Terhadap Karakteristik Material FeCuAl Dibuat Melalui Teknik Metalurgi Serbuk
Full text linkPaduan logam FeCuAl potensial dikembangkan untuk aplikasi bidang keteknikan dikarenakan sifat mekanis yang cukup baik. Perbaikan sifat mekanis bisa dilakukan melalui berbagai cara diantaranya dengan penambahan karbida. Penelitian ini bertujuan memperbaiki sifat mekanis dan fisi paduan FeCuAl melalui penambahan partikel SiC menggunakan teknik metalurgi serbuk. Partikel SiC (2~8) wt.% ditambahkan ke serbuk Fe, Cu, dan Al menggunakan model pencampuran horizontal milling pada kecepatan 300 rpm selama 2 jam. Proses cold compaction dengan penekanan 250 MPa selama 15 menit dilanjutkan dengan sintering pada temperatur 1000oC. Karakteristik mekanis paduan diperoleh melalui pengujian kekerasan Vicker, comprressive test, dan keausan. Observasi mikrostruktur menggunakan mikroskop optik dan scanning electron microscope (SEM) untuk melihat bentuk patahan. Pengukuran konduktivitas listrik menggunakan Keithley 6517B Electrometer. Hasil pengujian diperoleh densitas terendah 4,7 gr/cm3 dan kekerasan tertinggi 117,6 ±2,2 HV untuk model material FeCuAl-8 wt.%SiC. Hasil ini berkesesuaian dengan ketahanan aus, dimana laju keausan terendah 3,2±1,1 x10-6 (mm3/N.mm) dan kekuatan tekan tertinggi 526 MPa diperoleh untuk 8 wt.%SiC. Besarnya kekuatan FeCuAl-xSiC dipengaruhi oleh mikrostruktur, dimana hasil observasi memperlihatkan terbentuknya oksida dan porositas diantara butiran Fe/Cu. Lebih lanjut, hasil pengujian kelistrikan diperoleh keberadaan partikel SiC menurunkan konduktivitas listrik, nilai terendah diperoleh 23% IACS untuk kandungan 8 wt.%SiC. Berdasarkan data hasil pengujian tekan, kekerasan, dan keausan dapat disimpulkan bahwa penambahan SiC pada rentang 2-8 wt.% berhasil meningkatkan sifat mekanis paduan FeCuAl. Dibagian lain, peningkatan kandungan partikel SiC berdampak terhadap penurunan konduktivitas listrik paduan
PERMBERDAYAAN BANK SAMPAH BERBASIS DIGITAL DALAM UPAYA MENDUKUNG GREEN ACCOUNTING PADA BANK SAMPAH SEMPULUR ASRI GEDAWANG: PERMBERDAYAAN BANK SAMPAH BERBASIS DIGITAL DALAM UPAYA MENDUKUNG GREEN ACCOUNTING PADA BANK SAMPAH SEMPULUR ASRI GEDAWANG
No full textThe establishment of the Sempulur Asri Waste Bank began with the establishment of the Sempulur Asri Waste Bank located in RW 5, Gedawang Village, which was pioneered in 2014. The increase in the number of customers made management overwhelmed the management with the problems experienced, there were three main problems in the form of conventional customer account management, suboptimal marketing of the Sempulur waste bank, and incomplete and conventional production equipment. The solution to the problem of conventional customer account management is to digitize the management of the Sempulur Waste Bank account. Solutions for managers who do not master information technology, training and assistance in digitizing the management of the Sempulur Asri waste bank are absolutely necessary. Solutions for customers who are still unfamiliar with the use of information technology, training and assistance in digitizing for customer accessibility related to mutations. The implementation of empowerment is carried out by creating a system utilizing Google Drive for data and file storage. Then for Google Spreadsheet to recap each customer's account mutations and adding customers. In the implementation, it was later found that it was easy for customers to access the balance. This is because the implementation using email is considered less understandable by the customer. Then checking the account by the customer can use the website. This website is used for free using facilities from google site
Prosthetic Foot Mold Making with Photogrammetry Based Reverse Engineering Method
Full text linkProsthetic foot mold making is a crucial stage in the production of prosthetic feet that are in accordance with the anatomy and user needs. This research aims to develop a method for making prosthetic foot mold using a reverse engineering approach with photogrammetry techniques. The process begins with scanning the sole of the foot using photogrammetry methods to obtain a three dimensional model. The scanned model is then converted into a CAD design which is used as the basis for mold making. The mold design was made by considering ergonomic aspects and ease of manufacturing in the next stage. The results showed that the average deviation was within the range of ±0.65 mm or 0.42%, with a maximum deviation of 1.42%. This method is capable of producing precise casts that match the geometry of the original foot. With this approach, it is expected to improve the quality and customization of prosthetic products in the future
The Influence of Full Annealing Process Combined with Repetitive Hammering on the Mechanical Properties of AISI 316 Steel
Full text linkAISI 316 steel is known for its corrosion resistance, high hardenability, and good formability. It belongs to meta-stable austenitic stainless steel, where its microstructure can transform into α-martensite under treatments like Dynamic Plastic Deformation (DPD). This steel contains 16-18% Cr and 10-14% Ni. This study aims to analyze the mechanical properties of AISI 316 steel after annealing and after combining annealing with strain hardening through repetitive hammering. The research parameters included full annealing at 1050ºC with a holding time of 30 minutes, followed by repeated hammering for 30, 60, and 90 times, and annealing at 1050ºC with repeated hammering 30 times at the same temperature. A 5 kg iron load was used during the hammering process. The tests conducted were Optical Emission Spectroscopy (OES), hardness testing using the micro vickers method, tensile testing, microstructure analysis, and calculations of strain and thickness reduction. Results showed that the untreated specimen had a hardness of 269.3 VHN, while full annealing at 1050ºC reduced it to 165.2 VHN. Combining annealing with 30, 60, and 90 hammer blows increased hardness to 213.4, 228.5, and 251.4 VHN, respectively, demonstrating the effect of repeated hammering on the mechanical properties of AISI 316 steel.
 
PENINGKATAN KUAT LENTUR BETON FAST TRACK MUTU FS 45 DENGAN ADMIXTURE MR 73
Full text linkA number of studies and concrete trials have been undertaken in an effort to improve the quality of concrete and address common issues in the construction industry, such as project deadlines. Efforts that have been made to improve the quality of concrete include modifying the strength of high concrete at 7 days of age using chemical admixtures. This research aims to determine the effect of the MR 73 admixture on the flexural strength of concrete at 7 and 28 days of age. The research method used is quantitative experimentation. The research results show that concrete with an admixture of MR 73 at a dosage of 0.4% at 7 days of age has an average flexural strength of 43.5042 kg/cm ², while normal concrete at the same age has a flexural strength of 35.34 kg/cm ². At 28 days of age, concrete with an admixture of MR 73 at a dosage of 0.4% reaches an average flexural strength of 49.97 kg/cm ², compared to normal concrete which reaches 45.54 kg/cm ². The MR 73 admixture has been proven to increase the flexural strength of concrete by 23% at 7 days and by 10% at 28 days compared to normal concrete
Heat Source in a Pyrolysis Reactor Design for Energy Converting of Polypropylene into Fuel Oil at PPSDM Migas, Cepu
Full text linkFurnace-02 at PPSDM Migas is utilised in the petroleum processing of residual fuel. The efficiency value of furnace-02 is 62.71%, with 119,1763 Btu/h of heat being wasted through flue gas and a flow velocity of 164 m3/min. The heat value in the flue gas is utilised for the purpose of pyrolysis of the plastic, with a view to optimising energy use in the furnace. The process of plastic pyrolysis has been demonstrated to yield pyrolysis oil, which possesses a calorific value comparable to that of gasoline (10,520 kcal/kg). This pyrolysis oil has the potential to serve as a substitute fuel source for fossil fuels. The design of the pyrolysis system burner modification is such that its capacity is 75 kg/hour. The energy utilisation in the design amounted to 28,645.02 kJ/h, representing 2.3% of the total flue gas heat
IMPLEMENTASI SISTEM PEMERIKSAAN DAN PERBAIKAN KERUSAKAN PADA DINDING BANGUNAN DI KELURAHAN NGADIRGO KECAMATAN MIJEN KOTA SEMARANG: IMPLEMENTASI SISTEM PEMERIKSAAN DAN PERBAIKAN KERUSAKAN PADA DINDING BANGUNAN DI KELURAHAN NGADIRGO KECAMATAN MIJEN KOTA SEMARANG
No full textCommunity service in the form of implementing a system for inspecting and repairing damage to building walls in Ngadirgo Village, Mijen District, Semarang City aims to increase the insight and skills of local residents regarding the problem of cracks in building walls that occur due to ground movement. This activity starts from a site survey, preparation of tools and materials, training on the correct procedures, ensuring the implementation of correct repair methods and according to standards. Based on the results of surveys and interviews with local residents, the cracks in the walls of RW 2 Hall, Ngadirgo Village, Mijen District were caused by ground movement activities, resulting in non-uniform settlement of the building structure. The service team and students provide training and assistance to residents and bricklayers in Ngadirgo Village, Mijen District. The repair method used to repair cracked walls is the stitching metho
PENGARUH PRELOADING TERHADAP LAMA WAKTU KONSOLIDASI PADA TAHAP PRECONSTRUCTION STUDI KASUS PESISIR KOTA SEMARANG: PENGARUH PRELOADING TERHADAP LAMA WAKTU KONSOLIDASI PADA TAHAP PRECONSTRUCTION STUDI KASUS PESISIR KOTA SEMARANG
No full textThe problem of soft clay soil is currently one of the most worrying soil problems due to the increasing use of soft soil areas for construction needs. The main problem with soft clay soil is its nature which easily absorbs water but is difficult to release the water. The large amount of soft soil in the coastal area of Semarang City implies that in the construction process in the area, it is necessary to consider consolidation reduction. Soft clay soil takes a long time to reach 90% consolidation. This is because the permeability of soft clay soil is very small so that the process of dissipating water out is quite long. This dissipation process can be accelerated using engineering techniques, one of which is preloading. This process will further accelerate the consolidation process. This study was conducted to obtain the optimization of the embankment area against land subsidence on the coast of Semarang City using the numerical analysis method. From the research results, various variations were obtained for the area of embankment for a soil depth of 20 meters with a size of 30 x 30, the decline that occurred was 1.37 cm, a size of 40 x 40, the decline that occurred was 1.552 cm, a size of 50 x 50, the decline that occurred was 1.772 cm. While for the sea decline according to Steinbene
STUDI EKSPERIMEN KUAT LEKAT LEM PADA PASANGAN BETON RINGAN: STUDI EKSPERIMEN KUAT LEKAT LEM PADA PASANGAN BETON RINGAN
No full textIn modern construction, lightweight bricks are increasingly used as an alternative building material due to their advantages in terms of light weight, ease of installation, and energy efficiency. However, the strength of structures formed from lightweight brick masonry is highly dependent on the quality of the bond between the elements, particularly the use of adhesives such as construction glue. One crucial factor determining the bond strength is the configuration and length of the bonding surface used. This study aims to evaluate the effect of the number of bonding rows on the adhesive bond strength of lightweight brick masonry. Testing was conducted experimentally using one- and two-row bonding configurations. Each sample was subjected to compressive force through a 24.4 mm diameter cylindrical press. Results showed that the two-row configuration produced a higher bond strength, but with a larger coefficient of variation, indicating lower stability of the results. Increasing the bond length actually tended to decrease the bond strength, likely due to uneven distribution of glue and pressure. Furthermore, all test specimens fractured in the brick body, not at the bonding surface, indicating that the adhesive strength had exceeded the tensile strength of the lightweight brick. Regression analysis showed a very strong relationship between compressive force and bond strength, indicating that applied pressure was the dominant factor in bond effectiveness