Portal Jurnal Politeknik Negeri Semarang
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The Effect of Hot Air Flow Velocity on The Drying Characteristics of Turmeric in A Rotary Dryer
Get PDFTurmeric (Curcuma longa) is a rhizome plant widely used in the food, pharmaceutical, and cosmetic industries. This study aims to determine the characteristics of turmeric after the drying process and to analyze the effect of variations in hot air flow rate on moisture content reduction, drying rate, and thermal efficiency. Although various studies on turmeric drying have been conducted, most of these studies only tested one parameter, such as cylinder speed, drying temperature, and airflow rate, without considering the interaction of hot airflow rate in the rotary dryer system. The drying method in this study used a rotary dryer with a heat source from LPG combustion, at hot air flow rates of 5.2 m/s, 7.9 m/s, and 9.1 m/s with a drum rotation speed of 6 rpm for 360 minutes. The results showed that higher hot air flow rates accelerated the drying process. Optimal conditions were achieved at a speed of 9.1 m/s with a moisture content of 43.97%. Although drying was faster at higher speeds, the best thermal efficiency (23.36%) occurred at a speed of 7.9 m/s. Meanwhile, at a speed of 9.1 m/s, efficiency decreased to 22.39%
Optimization of Barium Sulfate (BaSO₄) Crystallization Using the Box-Behnken Design Method to Mitigate Scaling in Industrial Pipes
Get PDFThe precipitation of barium sulfate (BaSO4) in industrial piping systems is a major problem because it causes blockage, decreased productivity, and structural damage, including pipe rupture. Although there has been progress in understanding the mechanism of BaSO4 formation, some elements, such as the interaction of tartaric acid with BaSO4 crystals, the best parameters for reducing scaling, and the effectiveness of gas hydrate inhibitors, are still not fully understood. The objectives of this study were to find out how tartaric acid and BaSO4 crystals interact, find the ideal parameters to prevent scale formation, and assess the effectiveness of scaling inhibition techniques using gas hydrate inhibitor and scaling theories. This study used a Box-Behnken experimental design in the laboratory to optimize the temperature, solution concentration, and tartaric acid additive. The test was carried out under laminar flow conditions with a flow rate of 30 mL/min. After that, the morphology and composition of the scale were analyzed by SEM-EDX and XRD. The main results of the study showed that, under ideal conditions, the addition of tartaric acid significantly prolonged the induction time and reduced the mass of BaSO4 scale by up to 50%. This study reached the main conclusion that tartaric acid functions well as an anti-scaling agent and that ideal parameters can be used to effectively prevent scaling. This study is very helpful in developing more efficient and sustainable BaSO4 scaling mitigation methods for industrial applications
ANALISIS DEBIT BANJIR PADA SUB DAERAH ALIRAN (DAS) SUNGAI TABUK, PERBANDINGAN METODE HIDROGRAF SATUAN SINTETIK SCS DAN SNYDER
No full textFloods are a natural disaster that can occur during the rainy season in various watershed areas across many regions of Indonesia. Continuous heavy rainfall causes rivers to exceed their capacity, leading to flooding. The Sungai Tabuk sub-district, which comprises 20 villages and one urban village, is entirely affected by flooding, with the worst-hit area being Pemakuan Darat Village. To determine the magnitude of the flood discharge, a hydrological model simulation using the HEC-HMS software is necessary. The analysis was conducted by collecting data on the Sub-basin of Sungai Tabuk, which includes primary and secondary data. The data was processed to create a rainfall-runoff model using HEC-HMS. The rainfall distribution process was carried out using the Mononobe distribution. The method used is the SCS Curve Number, while direct runoff is analyzed using the HSS SCS and the HSS Snyder. The simulation results with observations dated January 1, 2021, using the Mononobe distribution method by SCS and Snyder, are as follows: the SCS method at the outlet Reach and Sink had the highest discharge of 1,430.2 m³/s, whereas the Snyder method had a discharge of only 1,092.3 m³/s. In contrast, the discharge observed in the field was 39.072 m³/s. It can be seen that the discharge values from the HEC-HMS software are significantly higher than the discharge values obtained in the field
PERSEPSI MAHASISWA POLITEKNIK NEGERI SEMARANG TERHADAP PELAYANAN BIDANG KEMAHASISWAAN UNTUK MENINGKATKAN KUALITAS PELAYANAAN PADA MAHASISWA POLITEKNIK NEGERI SEMARANG : PERSEPSI MAHASISWA POLITEKNIK NEGERI SEMARANG TERHADAP PELAYANAN BIDANG KEMAHASISWAAN UNTUK MENINGKATKAN KUALITAS PELAYANAAN PADA MAHASISWA POLITEKNIK NEGERI SEMARANG
No full textThis study aims to evaluate student perceptions of the quality of services provided by the student affairs sector at Politeknik Negeri Semarang. The method used in this research is a survey by distributing questionnaires to 100 active students as respondents. Data analysis was performed using multiple linear regression. The results showed that the dimensions of service quality such as tangible, reliability, responsiveness, and assurance have a significant influence on student satisfaction, while empathy has no significant effect. This study also provides recommendations for improving service quality in the field of student affairs in order to meet student expectations
PEMANFAATAN POLYURETHANE DENGAN VARIASI VOLUME SEBAGAI PERKUATAN STRUKTUR DINDING BATA RINGAN RUMAH PENDUDUK DI KECAMATAN MIJEN KOTA SEMARANG: PEMANFAATAN POLYURETHANE DENGAN VARIASI VOLUME SEBAGAI PERKUATAN STRUKTUR DINDING BATA RINGAN RUMAH PENDUDUK DI KECAMATAN MIJEN KOTA SEMARANG
No full textThe vulnerability to earthquake hazards in Semarang City is still quite low. Many people have houses that are not yet standardized to the Indonesian National Standards (SNI). Mijen District, Semarang City, is one of the districts that is quite prone to earthquake hazards because of its location close to the source of the Kaligarang fault. Therefore, it is necessary to provide preventive measures and measures for community housing buildings. The house is an earthquake-resistant building and is able to withstand sudden ground movements. By building houses that comply with Indonesian National Standards, it is hoped that damage to the building will be minimized and there will be no loss of life. By using light building materials and strong adhesive between joints, it will increase the ability to withstand seismic loads in a building. In wall construction, you can apply light bricks with polyurethane adhesive because the load caused is relatively light. Apart from being able to strengthen the bond between each layer of brick properly, this adhesive is easy to apply. It is hoped that this adhesive material will be capable of gluing and creating a strong bond in the lightweight brick layers. Varying polyurethane volume is needed to determine the effective and efficient quantity of polyurethane to produce a strong bond. For this reason, "Using Polyurethane with Varying Volumes to Strengthen the Structure of Light Brick Walls of Residents' Houses in Mijen District, Semarang City" is very important as a community service step in presenting innovations that are easy to implement independently by residents in earthquake-prone areas
EVALUASI PEMENUHAN KEBUTUHAN RUANG PARKIR DI KAMPUS POLITEKNIK NEGERI SEMARANG: EVALUASI PEMENUHAN KEBUTUHAN RUANG PARKIR DI KAMPUS POLITEKNIK NEGERI SEMARANG
No full textActivities that occur in an activity center will certainly cause vehicle parking activities. Parking facilities are a very important supporting factor and require extra attention for their development in the activity center. Parking problems are something that we often encounter in various locations of educational centers, shopping centers, hospitals, factories, universities and many other places. One real example that occurs in Semarang is on the Semarang State Polytechnic campus, every day active lectures are certainly always a buildup of vehicles that cause traffic activities around the Semarang State Polytechnic campus to become dense. Therefore, an evaluation is needed to fulfill the need for parking space on the Semarang State Polytechnic campus. In evaluating the fulfillment of parking needs, Parking Characteristics on the Semarang State Polytechnic Campus with a composition of 2-wheeled and 4-wheeled vehicles with a parking duration for each type of vehicle is 425 minutes and 546 minutes with a parking index of 104% and 277%. The need for parking space that must be provided on the Semarang State Polytechnic campus with each type of vehicle is 3622.3 for 2-wheeled vehicles and 140.8 for 4-wheeled vehicles
MSME Growth in a Learning Perspective: an Examination of Work Experience, Self-Efficacy, and Financial Literacy
Get PDFThis study aims to analyse the influence of work experience, self-efficacy, access to financing, financial management skills, and financial literacy on MSME growth in Karawang Regency with entrepreneurial learning as a mediating variable. This research uses a quantitative approach with a survey method of 120 MSME actors selected through purposive sampling technique. The data were analysed using Structural Equation Modeling-Partial Least Squares (SEM-PLS) with the help of SmartPLS 3 software. The results show that work experience and self-efficacy have a positive and significant direct effect on MSME growth, while access to financing, financial management skills, and financial literacy do not show a significant direct effect. However, all of the exogenous variables were shown to have significant indirect effects on business growth through entrepreneurial learning as a mediator. This finding reinforces the strategic role of Entrepreneurial Learning in bridging the influence of human and financial resources on business growth. This research provides a theoretical contribution to the development of Human Capital Theory and Entrepreneurial Learning Theory and suggests the need for MSME empowerment programme design that focuses on strengthening the entrepreneurial learning process in a practical, contextual, and sustainable manner
DESIGN AND IMPLEMENTATION OF AN X DOUBLE BAZOOKA ANTENNA IN A HYBRID COMMUNICATION SYSTEM
Get PDFThe double bazooka antenna is an antenna developed for military applications and later adapted by amateur radio enthusiasts for high-frequency (HF) communication. The double bazooka antenna consists of two elements: the main element, which functions as the transmitter element that transmits and receives radio frequency (RF) signals, and the auxiliary element, which serves to widen the bandwidth. The main element is the most significant factor influencing the antenna’s parameter characteristics. This study aims to realize a double bazooka antenna with a semi-directional radiation pattern at an operating frequency of 433 MHz, which will be applied as an external antenna in a hybrid communication system. The antenna material used in this study is RG-8 cable with a relative permittivity (εᵣ) of 2.3. Antenna parameter testing was conducted at the Telecommunication Engineering Laboratory of the State Polytechnic of Semarang using a Spectrum Analyzer, Vector Network Analyzer, Radio Frequency Generator, and Antenna Trainer Kit. The results of the double bazooka antenna parameter testing showed a return loss value of -23,345537 5 and a VSWR of 1:1.24 at a frequency of 433 MHz, which is in accordance with standards, and has a gain of 19.55 dBi with a semi-directional radiation pattern and vertical elliptical polarization. The double bazooka antenna was successfully implemented in a hybrid communication system, with test results showing that the antenna operates optimally.
Keywords: double bazooka antenna, radio communication, hybrid communication system, handy talki
PENYAJIAN LAPORAN KEUANGAN DESA PADA DESA LEREP KEC AMATAN UNGARAN BARAT KABUPATEN SEMARANG
Get PDFPenelitian ini bertujuan untuk mengetahui kesesuaian dalam penyajian laporan keuangan desa dan pemenuhan asas dalam setiap tahapan pengelolaan keuangan desa pada Desa Lerep Kecamatan Ungaran Barat Kabupaten Semarang dengan Permendagri No. 20 Tahun 2018. Data yang digunakan yaitu data kualitatif, data primer dan data sekunder. Pengumpulan data menggunakan metode observasi, wawancara dan dokumentasi. Hasil penelitian yang telah dilakukan menunjukkan bahwa penyajian laporan keuangan desa pada Desa Lerep berdasarkan jenis dan komponennya telah sesuai dengan Permendagri No. 20 Tahun 2018. Dalam penerapan asas pengelolaan keuangan desa sudah memenuhi asas partisipatif serta tertib dan disiplin anggaran namun belum sepenuhnya memenuhi asas transparansi dan akuntabilitas karena tidak adanya informasi mengenai pelaksana kegiatan anggaran beserta tim yang melaksanakan kegiatan, tidak adanya tahap pelaporan pada semester pertama dan kurangnya dokumen yang dilaporkan pada tahap pertanggungjawaban