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An Evaluation Method of Ship-Tracking Algorithms for High-Frequency Surface Wave Radar considering High Maneuvers Generated by the MMG Model
No full textThelong-distance coverage of high-frequency surface wave radar (HFSWR) has promoted it as an enormous means for ship monitoring on the country's maritime territory. Since it is a primaryradar, noncooperative targets can also be detected. However, this radar also has a shortcoming of low spatial and temporal resolutions due to the narrow available bandwidth in the HF band. This limitation can reduce the performance of ship detection and tracking, especially for highly maneuvering ships. This paper proposes a new method to assess the tracking algorithm for a high-maneuvering ship. The absence of a high-maneuvering plot in the AIS data and existing analytical models are replaced by the MMG model run on MANSIM software. The linear, turning, and zigzag motions are generated and used to evaluate the tracking algorithms. The Monte Carlo simulation was conducted regarding the degradation of spatial resolution in the higher radial range. The tracking performance was analyzed by calculating the RMSE of four parameters, i.e., absolute position, radial range, bearing angle, and speed. For a trial case, four tracking algorithms were evaluated, i.e., Kalman filter (KF), extended Kalman filter (EKF), unscented Kalman filter (UKF), and particle filter (PF). The evaluation results showed that the EKF tracker had a minor error for the linear track with RMSE of absolute position, radial range, bearing angle, and speed being 1.368 km, 0.526 km, 1.550°, and 0.005 m/s, respectively. Otherwise, the UKF performed slightly better than EKF for the high maneuver targets. The RMSE of absolute position, radial range, bearing angle, and speed were 1.649 km, 0.639 km, 1.919°, and 0.165 m/s, respectively. The results also ensure the applicability of the MMG model to evaluate the tracking algorithm's performance in HFSWR
Microwave-assisted green synthesis of nitrobenzene using sulfated natural zeolite as a potential solid acid catalyst
No full textNatural zeolite and sulfated natural zeolite catalyst materials have been successfully prepared, characterized, and applied as a replacement for the role of a sulfuric acid catalyst in the synthesis of nitrobenzene. Natural zeolites were prepared into uniform-sized powders and then refluxed with H2SO4 with varying concentrations of 0, 1, 2, 3, and 4 M, proceeded by calcination with N2 gas flow (labeled as NZ, SNZ-1, SNZ-2, SNZ-3, and SNZ-4). Nitrobenzene was synthesized in a batch microwave reactor using natural zeolite and sulfated natural zeolite catalysts with the best acidity value. The results showed that the sulfuric acid treatment of natural zeolite caused changes in its physical and chemical characteristics. The NZ catalyst has an acidity value of 1.742 mmol g�1, and the 2 M concentration variation resulted in the sulfated natural zeolite with the best acidity value of 1.625 mmol g�1. The optimal amount of catalyst required is 1.0 g. Both catalysts are selective toward the nitration reaction of benzene. The average benzene conversion produced for each catalyst was 41.53 ± 3.61% and 58.92 ± 1.37%. Furthermore, the SNZ-2 catalyst has better reusability for three reaction runs. Graphical abstract: Figure not available: see fulltext
Performance analysis of a drop-swap terminal to mitigate truck congestion at chemical sites
No full textTruck congestion at chemical sites is a persistent problem that is difficult to solve, even using a truck appointment system. This study presents an alternative solution to improve the flexibility of chemical sites by creating a drop-swap terminal adjacent to the site location. The terminal serves as an intermediate depot where the trucks can drop empty containers and swap them with preloaded containers without entering the site. This study aims to evaluate the performance of such a solution in mitigating truck congestion at chemical sites. The problem is modeled as a nonstationary semi-open queueing network with time-varying arrivals. We propose a combination of a fluid-flow approximation and a decomposition-aggregation method to estimate the time-dependent performance of the system. A chemical site in the Netherlands is presented as a case study. Several scenarios are tested and evaluated. Numerical results show that a drop-swap terminal can effectively reduce truck idling time and increase logistics efficiency at chemical sites. We also found that swapping containers on chassis is a cheaper and greener option to operate the terminal. However, the investment needed to support the operation should not be overlooked to sustain the benefits. The study concluded with several key messages for site operators who wish to maximize the benefit from a drop-swap terminal
Model linier efek campuran bivariat untuk data longitudinal
No full textThe development of a mixed effects linear model with one response variable into two response variables is defined as a bivariate mixed effects linear model. In general, co-modelling is required to model two or more correlated longitudinal processes simultaneously. This is done to understand the relationship between the response variables over time. The method for estimating parameters in a bivariate mixed effect linear model uses the Expectation Maximization (EM) algorithm.
Data application for a linear model of bivariate mixed effects, namely the results of medical records of examination of systolic blood pressure and diastolic blood pressure at one of the health centers in Yogyakarta. In a follow-up study of hypertension, both systolic blood pressure and diastolic blood pressure were measured repeatedly for each patient and the aim was to investigate changes in the two response variables and examine the factors that affect changes in systolic blood pressure and longitudinal diastolic blood pressure over time. time in hypertensive patients together.
The results of the analysis show that the factors of time of visit, age and body weight have a significant effect on changes in systolic blood pressure and diastolic blood pressure. Joint modeling of both systolic blood pressure and diastolic blood pressure responses yielded a strong positive relationship. This means that if the systolic blood pressure variable increases, it will be followed by an increase in the diastolic blood pressure variable.
Keywords: Bivariate Mixed Effects Linear Model, Longitudinal, Expectation Maximization, Systolic Blood Pressure, and Diastolic Blood Pressure
Physicochemical, structure and functional characteristics of Tacca leontopetaloides starches grown in Indonesia
No full textUnderstanding the physicochemical, structure and functional characteristics of tacca tuber (Tacca leontopetaloides) starch is crucial as a scientific basis for its development, especially in the food industry. Despite the abundance of starch in Indonesian tacca tubers, its potential remains largely untapped. This research aims to determine the physicochemical, structure and functional characteristics of tacca tuber starch from three different regions in Indonesia: Bangkalan, Garut and Sumenep. Wet extraction yielded tacca tuber starch with yields ranging from 21.26 to 26.42. Significant differences (p<0.05) were observed in proximate composition (ash, lipid, and protein), starch purity (97.35-98.48), amylose content (32.81-35.26), and functional properties like swelling power (9.67-10.51 g/g at 95°C), solubility (4.93-5.87 at 95°C), water holding capacity (0.77-0.90 g/g), oil holding capacity (0.62-0.71 g/g), and relative crystallinity (24.22-27.03). Thermal properties and pasting properties (except breakdown viscosity) exhibited significant variations. The gelatinization temperature profile of tacca tuber starch ranged from 57.92 to 76.38℃C, with an ∆H value of around 3.81-4.62 J/g. Meanwhile, the temperature of tacca tuber starch paste ranged from 72.12 to 72.88℃C. Tacca tuber starch granules are polygonal, elliptical, oval to slightly ellipsoidal, with an average granule diameter of 20.21-40.43 μm. Based on the X-ray diffraction pattern, tacca tuber starch shows the CA-type, containing orthorhombic and hexagonal structure crystals. Tacca tuber starch has a high lightness (92.01-93.62) and whiteness index (91.68-92.74). In conclusion, the cultivation location significantly influences the physicochemical, structural, and functional characteristics of t acca tuber starch
Glycerolysis-Interesterification of Palm Olein and Coconut Oil Blend using Two High-Shear Continuous Stirred Tank Reactors
No full textThis study aimed to synthesize structured lipids containing high mono- and diacylglycerol by glycerolysisinteresterification of palm olein and coconut oil blend in two high-shear continuous stirred tank reactors in series. The result showed that various flow rates of 11 mL/min to 23 mL/min did not significantly increase mono- and diacylglycerol concentration, while at a flow rate of 26 mL/min only a low concentration of mono- and diacylglycerol was formed. However, a flow rate 20 mL/min and an agitating speed of 2000 rpm produced mono- and diacylglycerol concentration of 61.7 with the highest productivity of 2.1/min and a triacylglycerol conversion of 64.6. The slip melting point, melting point, hardness, emulsion capacity, and stability were 23.77 oC, 30 oC, 14.6 N, 65.15, and 59.15, respectively. The product's solid fat content at 25 oC was lower than cocoa butter. The product contained β' and β crystals, thus it can be applied as a cocoa butter substitute
Metode Tes Usap Untuk Uji Kebocoran Sumber Tertutup Menggunakan Spektometer Gamma Dengan Detektor NaI(Tl)
No full textKegiatan Kerja Praktik merupakan sebuah kegiatan akademis yang memiliki
peran penting bagi mahasiswa untuk mempraktikan ilmunya dalam dunia kerja.
Departemen Teknik Nuklir dan Teknik Fisika mewajibkan mahasiswanya untuk
melaksanakan Kerja Praktik dan diharapkan dalam pelaksanaannya memiliki
konsentrasi yang sama dalam bidang ke-nukliran. Salah satu instansi yang memiliki
konsentrasi sejenis adalah NuklindoLab yang merupakan instansi penyedia jasa
layanan dalam bidang keselamatan radiasi baik bagi industri maupun bagi rumah
sakit.
Pada pelaksanaan Kerja Praktik di NuklindoLab ini tugas yang diberikan
adalah terkait Metode Tes Usap Untuk Uji Kebocoran Sumber Tertutup
Menggunakan Spektometer Gamma Dengan Detektor NaI(Tl). Pengujian kebocoran
sumber tertutup dengan menggunakan metode tes usap ini sudah sering dilakukan
dalam bidang industri terutama untuk kegiatan logging dan gauging. Pada
NuklindoLab terdapat beberapa sampel yang dapat digunakan untuk melakukan
pengujian dengan metode tes usap, yaitu sampel 137Cs plat dan 137Cs keramik.
Pada pengujian dengan sampel ini didapatkan hasil berupa persamaan
kalibrasi energi dan kalibrasi efisiensi dengan nilai kalibrasi energi yaitu
y = 1,8164x – 20,851 serta persamaan kalibrasi efisiensi yaitu y = 27,29x⁰¹⁶⁵¹
. dari
kedua persamaan tersebut dapat diketahui nilai konsentrasi radinuklida sampel yaitu
sebesar 39 Bq untuk 137Cs plat dan 91 Bq untuk 137Cs keramik
INSPEKSI PRODUK SEMEN DENGAN XRF (X-RAY FLUORESENCE) PADA QUALITY CONTROL PT SOLUSI BANGUN INDONESIA TBK
No full textKerja Praktik yang telah dilaksanakan di PT Solusi Bangun Tbk, perusahaan yang mengoperasikan empat pabrik semen masing-masing di Narogong, Jawa Barat; Cilacap, Jawa Tengah; Tuban, Jawa Timur dan Lhoknga, Aceh. Perusahaan PT Solusi Bangun Tbk. menyediakan fasilitas Kerja Praktik secara luring. Perusahaan publik Indonesia ini, mayoritas sahamnya (83,52%) dimiliki dan dikelola oleh PT Semen Indonesia (Persero) Tbk merupakan produsen semen terbesar di Indonesia dan Asia Tenggara. Perusahaan PT Solusi Bangun Indonesia Tbk menjalankan usaha yang terintegrasi terdiri dari semen, beton siap pakai, dan produksi agregat. Pada proses produksi dilakukan pengendalian mutu (quality control) dengan metode uji tak merusak/non-destructive testing (NDT) untuk mengidentifikasi dan memastikan kualitas produk sesuai dengan standar. Uji tak merusak yang dilakukan pada produk dan bahan produksi semen menggunakan XRF (X-Ray Fluoresence) dengan preparasi sampel berupa pressed pallete dan fuse bead. Titik pengambilan sampel uji berada di beberapa titik mulai dari tambang hingga pack house. Adapun pelaksanaan tugas khusus dengan topik “Kalibrasi XRFuse 2 Electric Fusion machine dengan preparasi fuse bead dan X-Ray Bruker S8 Lion” dan sub-topik Kalibrasi XRFuse 2 dan Bruker S8 Lion dengan semen Standar Reference Material.
Kata Kunci : Industri Semen, Non-destructive test, Quality Control, Pemanfaatan Sinar X, XRF (X-Ray Fluoresence), Fuse bead, Kalibrasi XRFuse 2
Feature Representation for Network Intrusion Detection System Trough Embedding Neural Network
No full textComputer network technology is growing rapidly, but cyberattacks are also increasing in number and variants that occur every year. Anomaly-based network intrusion detection system (NIDS) is still vulnerable to false positive rates even though it has used a machine learning approach to detect zero-day attacks on network traffic. Deep learning can provide advanced solutions to this problem. However, deep learning requires special handling to process tabular NIDS datasets with highly sparse categorical and numerical data. To overcome this, we propose a new embedding method implemented by embedding not only categorical data but also numerical data to provide the best representation features for deep learning models. The proposed method was evaluated with other deep learning and machine learning models with results outperforming all models based on the f1-score macro using the CSE-CIC-IDS-2018 dataset
Production competitiveness of regional sorghum genotypes against new, enhanced varieties and their morphological traits in Gunung Kidul, Yogyakarta, Indonesia
No full textSorghum is an important cereal crop after rice, maize, wheat and barley. Sorghum can be a potential local food to supportnational food security and to anticipate the threat of a world food crisis. One effort that can be madeis to optimize the land by using adaptivesorghum varieties planted during the rainy season. Various new superior varieties have been released through the Ministry ofAgriculture, but the germplasm withapotential to be local food has not been utilized optimally. Several studies on sorghum have been carried out from both cultivation and post-harvest aspects, but to continue the research relay and to participate in meeting national food needs,characterization of local varieties needs to be carried out as a first step in plant breeding activities.This study aims to determine the performance of six genotypes of new high-yielding sorghum varieties and localvarieties grown duringthe rainy season in Karangmojo Village, Karangmojo Sub-district, Gunung KidulDistrict, Yogyakarta Province, fromOctober 2022toMarch 2023. The design used was a Randomized Block Complete Design, with 5 repetitions. The resultsshowed the significantly different effect of genotypes on the parameters of plant height, panicle length, panicle width, 1000 seed weight, floweringage, stem diameter, harvesting age, panicle weight per plot, and production per hectare