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"Berkurangnya jumlah bahan bakar terbarukan pasokan karena sangat tinggi penggunaan transportasi pribadi memimpin banyak peneliti untuk membuat beberapa inovasi untuk meningkatkan efisiensi konsumsi bahan bakar. Konsumsi bahan bakar adalah terkait dengan jumlah udara dan menyeret kekuatan yang melewati tubuh bentuk transportasi. Berdasarkan teori yang telah kami pelajari, semakin tinggi tarik kekuatan pada transportasi tubuh lebih tinggi konsumsi bahan bakar, karena jumlah atas kekuatan tarik yang menyebabkan kebutuhan transportasi lebih banyak energi untuk membentuk beberapa daya kecepatan. Salah satu teknologi yang dapat mengurangi aerodinamis tarik kekuatan adalah aplikasi jet sintetis aktuator aliran kontrol aktif sebagai suatu modifikasi sederhana transportasi model untuk mengurangi aerodinamis tarik pada model transportasi. Fokus dari penelitian ini adalah analisis eksperimental variasi diameter lubang efek dari kerucut membentuk rongga sintetis jet aplikasi pada terbalik Ahmed tubuh model. Variabel independen yang diterapkan dalam percobaan ini adalah perubahan yang persegi, segitiga, gelombang sinus frekuensi yang berkisar dari 90 Hz untuk 130 Hz dengan interval frekuensi adalah 10 Hz, dan kecepatan aliran udara angin yang mulai dari 40 km/jam untuk 60 km/jam. Variabel gratis adalah diameter lubang rongga variasi; Ada 3 mm, 5 mm dan 8 mm. Fokus penelitian ini adalah eksperimental metode analisis. Berdasarkan hari percobaan, jenis gelombang persegi dengan frekuensi 110 Hz memiliki tertinggi tarik persentase pengurangan koefisien untuk lubang diameter 3 mm dan 8 mm, persentase pengurangan nilai koefisien drag adalah 9.93 untuk diameter lubang 3 mm dan 8,37 untuk 8 mm diameter lubang. 5 mm diameter lubang memiliki persentase terendah tarik pengurangan; nilai adalah 5,58.

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The decreasing number of non renewable fuel supply due to the very high use of private transportation leads many of researcher to make some innovation to improve the fuel consumption efficiency.The fuel consumption is related to the amount of air and drags force that passes through the body shape transportation.Based on the theory that we had learned, the higher drag force on transportation body the higher fuel consumption, since the upper amount of drag force causing the transportation need more energy to form some speed power.One of the technologies which can reduce the aerodynamic drag force is the application of synthetic jet actuator of flow active control as a modification of simple transportation model to reduce the aerodynamic drag on transportation model.The focus of this research is the experimental analysis of the effect orifice diameter variations of the conical shape cavities synthetic jet application on reversed Ahmed Body model.The independent variables that applied in this experiment are the change of the square, triangle, sine wave frequencies that range from 90 Hz to 130 Hz with the frequency interval is 10 Hz, and the wind airflow velocities which ranging from 40 km hr to 60 km hr.The free variable is the orifice diameter of cavity variations there are 3 mm, 5 mm and 8 mm.This research focus is experimental method analysis.Based on the recent experiment, the square wave type with a frequency 110 Hz has the highest drag coefficient reduction percentage for the orifice diameter 3 mm and 8 mm, the value coefficient drag reduction percentage is 9.93 for 3 mm orifice diameter and 8.37 for 8 mm orifice diameter.The 5 mm orifice diameter has the lowest percentage drag reduction the value is 5.58."

"Untuk mengurangi hambatan drag aerodinamik pada bluff body perlu adanya pengaturan aliran separasi, sebagai salah satu penyebab adanya hambatan pada kendaraan. Penelitian ini merupakan kajian dasar pengembangan dari pengontrolan separasi aliran turbulen yang merupakan suatu fenomena yang terjadi pada aerodinamik khususnya dalam desain bodi kendaraan. Tujuan penelitian ini adalah untuk menganalisa penurunan drag yang terjadi pada bluff body model kendaraan akibat pemasangan aktuator jet sintetik.Penelitian ini dilakukan melalui metode eksperimen dan metode komputasi. Langkah pertama penelitian adalah mengkarakterisasi aktuator tersebut dari segi bentuk kaviti, besarnya diameter orifis dan frekwensi eksitasi yang diberikan terhadap membran aktuator serta kemampuan aktuator membentuk cincin vortek. Bentuk cavity-nya, yaitu bola, tabung dan kerucut dengan diameter orifisnya adalah 3 mm, 5 mm dan 8 mm. Frekwensi eksitasi yang diberikan terhadap membran aktuator antara 20 Hz 200 Hz dengan bentuk gelombang quad, sinusoidal dan triangular. Langkah kedua adalah menghitung besarnya penurunan drag yang terjadi pada model reverse Ahmed body yang dipasangi aktuator jet sintetik pada bagian belakangnya. Pengujian ini meliputi pengaruh perubahan bentuk kaviti dan diameter orifis terhadap penurunan drag model uji. Frekwensi eksitasi yang diberikan pada membran ini antara 90Hz 130 Hz dengan bentuk gelombang yang sama.Dari hasil penelitian didapatkan bahwa model uji reversed Ahmed body yang menggunakan aktuator jet sintetik dengan kaviti K-3 sebagai alat kontrol alirannya dapat mengurangi drag. Pada kondisi kecepatan freestream 13,9 m/s dan aktuator bekerja pada frekwensi eksitasi 110 Hz dengan gelombang quad, pengurangan drag yang dihitung melalui metoda eksperimen sebesar 17,6 atau 18,62 secara metoda simulasi. Kaviti K-3 ini memiliki performa yang paling baik dibandingkan dengan tipe lainnya. Kaviti ini dapat membentuk cincin vortek pada frekwensi eksitasi 80 ndash; 150 Hz. Kecepatan semburan maksimum kaviti ini sebesar 10,8447 m/s pada frekwensi eksitasi 110 Hz dengan gelombang berbentuk quad. Kedua metoda penelitian ini mendapatkan hasil yang sama.

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To reduce aerodynamic drag on the bluff body it is necessary to adjust the flow of separation, as one of the causes of vehicle resistance. This study is a basic study of the development of turbulent flow separation control which is a phenomenon that occurs in aerodynamics, especially in vehicle body design. The purpose of this research is to analyze the decrease of drag which happened to bluff body model of vehicle caused by installation of synthetic jet actuator.This research is done through experimental method and computation method. The first step of the research is to characterize the actuator in terms of cavitary form, the magnitude of the orifice diameter and the excitation frequency given to the actuator membrane and the actuator 39;s ability to form the vortex ring. Its cavity form, ie balls, tubes and cones with orifice diameter is 3 mm, 5 mm and 8 mm. The excitation frequency applied to the actuator membrane is between 20 Hz 200 Hz with quad, sinusoidal and triangular waveforms. The second step is to calculate the amount of drag decline that occurs in the reverse Ahmed body model fitted with synthetic jet actuators on the back. This test includes the effect of cavitary form changes and orifice diameter on the decrease of drag test model. The excitation frequency applied to this membrane is between 90Hz 130 Hz with the same waveform.From the results of the research it was found that the reversed Ahmed body test model using synthetic jet actuator with Kaviti cavity as its flow control tool can reduce drag. At 13.9 m / s freestream velocity conditions and actuators working at 110 Hz excitation frequencies with quad waves, the drag reduction calculated by experimental method was 17.6 or 18.62 by simulation method. Kaviti K-3 has the best performance compared with other types. This cavity can form a vortex ring at an excitation frequency of 80 - 150 Hz. The maximum cavity burst rate is 10.8447 m / s at 110 Hz excitation frequency with quad wave. Both methods of this research get the same result."

"This paper presents a baseline study of the development of turbulent flow separation for controlling aerodynamic phenomena, especially in the design of the vehicle body. The purpose of this study was to analyze the performance of synthetic jet actuators (SJAs) as one of the tools that can be used in reducing the flow controller separation area on the bluff body model of the vehicle. To get maximum results in the performance of the SJA, this research starts with characterizing the actuator, including changes in the shape of the cavity and orifice diameter. Cavity shapes tested were half-ball (B), tube (T) and cone (K), while orifice diameters of 3, 5 and 8 mm were examined. The study was conducted using both computational and experimental approaches. Results from both types of research methods were compared and displayed in graphical form. These results serve as a reference for determining future research. The experimental results, in the form of the flow rate for each type of cavity, determined the ability of different cavity conditions to form vortex rings, whereas in CFD simulations, the formation of vortex rings was demonstrated via the visualization of flow contours. Vortex rings occurred in cavity conditions B3, T3, T5, K3 and K5. Vortex rings were not formed on any type of cavity with an orifice having a diameter of 8 mm."

"Inter-island freight transport costs in eastern compared to western Indonesia are relatively high, caused by operator charges for roundtrip fees. In order to make the distribution of freight efficient, the network of freight transport needs to be rationalized on a regional basis. The output from the regional model counts are few and far between in relation to intercity traffic volume data, and the disaggregate model at a regional level requires more effort in conducting travel route surveys. Therefore, aggregated analysis is preferable initially, based on the traffic volume and the commodity flow for inter-island freight transport. The accessibility and connectivity of the land use can be obtained from the freight distribution model as a measurement to evaluate different land use scenarios and also to provide feedback for land use modeling, as a parameter for freight location choice. With a freight distribution model to identify freight commodity supply and demand in a particular region, potential freight transport generation uses such variables, which consider generalized transport costs. Using the Furness and Maximum Entropy models, the results indicate that Furness model finishes in the 4th iteration and Maximum Entropy in 6th, while the negative exponential function offers the best calibrated estimation, using sea freight movement data. It was also found that the positive value of ? means that any increment of travel time decreased the rate of freight flow, which mirrored the conditions in reality: the higher travel costs, the fewer the number of flows between zones. The data is analyzed in the context of modeling intra-city freight flow in the archipelagic region of northern Maluku."

"COVID-19 adalah penyakit yang disebabkan oleh virus SARS-CoV-2 dan menyerang sistem pernapasan manusia. Selain menganggu kesehatan fisik, pandemi COVID-19 juga memberikan dampak psikologis, salah satunya adalah tingkat stres yang meningkat pada masyarakat. Penelitian ini bertujuan untuk mengidentifikasi faktor-faktor yang berasosiasi dengan tingkat stres pada pandemi COVID-19. Dalam mencapai tujuan tersebut, penelitian ini menggunakan metode classification tree dan regresi logistik multinomial. Sebelum melakukan proses identifikasi faktor menggunakan classification tree, dilakukan penanganan masalah imbalance data menggunakan metode SMOTE. Selanjutnya, dilakukan kuantifikasi risiko faktor-faktor yang teridentifikasi pada classification tree menggunakan analisis regresi logistik multinomial. Kinerja model diukur menggunakan nilai precision, recall, F1-Score, dan AUC. Hasil yang diperoleh adalah model classification tree dengan penanganan imbalance data menggunakan SMOTE dapat meningkatkan kinerja model dengan nilai precision 0,5980, nilai recall 0,8653, nilai F1-Score 0,7072, dan AUC 0,702. Dengan model tersebut, didapatkan faktor-faktor yang teridentifikasi berasosiasi dengan tingkat stres pada pandemi COVID-19 adalah Total_OECDInsititutions, Total_CoronaConcerns, dan Age. Peningkatan nilai Corona Concerns cenderung memberikan risiko peningkatan tingkat stres, sedangkan peningkatan nilai OECDInsititutions dan Age cenderung memberikan risiko penurunan tingkat stres.

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COVID-19 is a disease caused by the SARS-CoV-2 virus that attacks the human respiratory system. In addition to disrupting physical health, the COVID-19 pandemic also has psychological impacts, one of which is an increased level of stress. This study aims to identify factors associated with the level of stress during the COVID-19 pandemic. The study employs the classification tree method and multinomial logistic regression. Prior to the factor identification process using the classification tree, the issue of imbalanced data is addressed using the SMOTE method. Subsequently, the quantification of risk factors identified in the classification tree is conducted using multinomial logistic regression analysis. The model's performance is measured using precision, recall, F1-score, and AUC values. The results obtained indicate that the classification tree model with the handling of imbalanced data using SMOTE can improve model performance, with a precision value of 0,5980, recall value of 0,8653, F1-score value of 0,7072, and AUC value of 0,702. With this model, the identified factors associated with the level of stress during the COVID-19 pandemic are Total_OECDInstitutions, Total_CoronaConcerns, and Age. An increase in Corona Concerns tends to pose a risk of increased stress levels, while an increase in OECD Institutions and Age tends to pose a risk of decreased stress levels."

"Increasing energy demand, in line with the rate of population growth, is always followed by the pace of the waste dump. Where the largest percentage comes from organic waste, it is potentially utilized as raw material of biomass mixture for emission reduction efforts in fuel conversion from waste energy. The main objective of this paper is to study the characteristics of co-gasification, especially gasification temperature, lower heating value and gas emission, on the performance of the biomass gasification process in a downdraft fixed bed gasifier. In this study, organic waste used twigs, coconut fibers and rice husks in the pelletization as raw materials on the combustion technology Downdraft Gasifier. Methods were carried out by co-gasification techniques between WCF (wood-coconut fibers) pellet and rice husk on 100% pellet composition, 75:25, 50:50, 25:75 and 100% rice husk. Syngas testing is done with direct measurement on the burner with TCD type Shimadzu 8A gas chromatography. The highest reactor temperature in the pyrolysis zone was 400oC to 850oC and the temperature in the oxidation zone was 1000oC to 1200oC. The result of the synthetic gas testing obtained the highest lower heating value (LHV) in WCF 100% pellet composition at 4.07 MJ/Nm3 with 85% efficiency. The lower heating value of the lowest syngas in a 100% pellet composition was 2.99 MJ/Nm3, where the increase of WCF pellets will increase the LHV syngas value. This resulted in visually low tar content and low ash particles in all compositions of approximately 30 to 35% of the initial mass of each composition, with the lowest ash in 100% rice husk composition at 0.29 g."

"This study investigated the possibility of developing a synthetic fill material by combining industrial waste materials, thus, integrating the properties of cohesion and friction as a replacement for natural soil. Biosolids and steel slag were selected for proportioning of the synthetic fill material. They were blended in different proportions and the geotechnical properties of the various blends were investigated to determine the strength and bearing of the blended synthetic material for fill applications. The results of the investigation were encouraging with the index properties of the blends better than those of biosolids. It was found that 25% to 40% steel slag blending produced the maximum strength and bearing. The investigation revealed that blending of industrial waste materials has the potential to perform the function of a synthetic fill material in road embankments and backfills. However, further studies are recommended to investigate its long term compressibility and permeability and further improvement of bearing to meet local standards."

"Sifat menularnya virus COVID-19 mengakibatkan masa lockdown yang berkelanjutan, sehingga terjadi peningkatan signifikan terhadap pekerjaan dan pembelajaran secara daring di Jerman. Banyak perusahaan mengevaluasi kondisi kerja yang baru menguntungkan dan berencana untuk memanfaatkan kesempatan ini untuk mempertahankan bekerja dari rumah. Dengan lebih banyak waktu di rumah, kebiasaan hidup penghuni-penghuni, yang sebelumnya tidak berada di rumah untuk bekerja, berubah. Demikian, pola konsumsi listrik mereka juga meningkat. Skripsi ini menyampaikan sebuah penelitian mengenai pengaruh pandemi COVID-19 terhadap profil beban perumahan dengan rumah tangga yang sebelumnya tidak berada di rumah pada siang hari karena berada di kantor, melalui profil beban yang dihasilkan secara sintetik.Profil beban sintetik memampukan pemodelan pola konsumsi listrik perumahan untuk sekelompok rumah tangga. Model ini bergantung pada input data mengenai aspek teknis dan aspek sosial dari elektronik konsumen yang ada di rumah. Pandemi mengubah secara signifikan aspek sosial dari model ini karena ada transisi dari bekerja di kantor menjadi bekerja dari rumah. Hasil dari profil beban sintetik yang dihasilkan akan dianalisa dan dibandingan dengan model yang ada sebelum pandemi.

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The contagious nature of COVID-19 virus has led to extended period of stay-at-home order which triggers significant increase in teleworking and online-learning in Germany. More companies evaluate the new working condition as beneficial and have planned to utilize this opportunity to sustain working from home. With more time home, the lifestyle of people who used to be absent from the house to work changes. Consequently, the electrical consumption pattern also increases. This thesis presents a study in the influences of the COVID-19 pandemic to residential load profile of households that used to be absent during the day as they are in the office, through the synthetically generated load profile.

Synthetic load profile allows modelling of residential electrical consumption pattern for a group of households. It relies on input data regarding the technical aspect and social aspect of consumer electronics available at home. The pandemic significantly changes the social aspect of the model with transition from working in the office to working from home. Result from the synthetic load profile generated is analyzed and compared to previous model before the pandemic."

"Dalam era digital saat ini, banyaknya data finansial yang melimpah dan tidak berlabel menimbulkan tantangan dalam pemilihan teknik pendeteksian outlier (outlier detection) yang optimal. Penelitian ini bertujuan untuk menangani tantangan tersebut dengan membandingkan model unsupervised outlier detection pada data sintetis yang dirancang untuk meniru karakteristik data finansial nyata. Sebagai studi kasus, penelitian ini menggunakan data Laporan Harta Keuangan Penyelenggara Negara (LHKPN) tahun 2022. Proses penelitian mencakup pengumpulan data, pemrosesan, pembuatan data sintetis, pengujian sepuluh algoritma outlier detection, dan penerapan model terbaik pada data LHKPN tahun 2022. Dari proses ini, model Median Absolute Deviation (MAD) dengan threshold 7.8 teridentifikasi sebagai yang paling efektif pada data sintetis yang meniru data LHKPN. Penelitian ini juga menemukan hyperparameter terbaik untuk model lain dan melakukan analisis skor outlier pada data nyata. Hasilnya memberikan wawasan baru dan menunjukkan potensi investigasi lanjutan dalam outlier detection pada data finansial tidak berlabel, dengan pendekatan yang menyeluruh mulai dari analisis distribusi data hingga pengujian model pada data sintetis dan asli.

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In the current digital era, the abundance of unlabeled financial data poses challenges in selecting optimal outlier detection techniques. This research aims to address these challenges by comparing unsupervised outlier detection models on synthetic data, designed to mimic real financial data characteristics. Using 2022 data from the Laporan Harta Keuangan Penyelenggara Negara (LHKPN) as a case study, the research process includes data collection, processing, creating synthetic data, testing 10 outlier detection algorithms, and applying the most effective model, identified as Median Absolute Deviation (MAD) with a threshold of 7.8, on synthetic data based on LHKPN data. The study also finds the best hyperparameters for other models and conducts real data outlier score analysis, providing new insights and demonstrating further investigation potential in outlier detection for unlabeled financial data."

"Dalam beberapa dekade terakhir, pariwisata telah menjadi salah satu sektor ekonomi paling dinamis dan paling cepat berkembang di dunia. Pemerintah mengeluarkan kebijakan pengembangan ekonomi yang juga berkaitan dengan pengembangan pariwisata, yakni Kawasan Ekonomi Khusus. Salah satu KEK yang berkaitan dengan pengembangan pariwisata dan merupakan salah satu dari 5 Destinasi Super Prioritas yang dicanangkan pemerintah adalah Kawasan Ekonomi Khusus Mandalika. Penelitian mengenai KEK pariwisata terhadap perekonomian di Indonesia hanya terbatas pada studi kualitatif dan lebih banyak terfokus pada KEK industri sementara KEK pariwisata juga berpotensi memberikan manfaat. Menggunakan data tingkat kabupaten/kota dari tahun 2000 sampai dengan 2021, penelitian ini menggunakan metode synthetic control untuk mengestimasi dampak dari keberadaan KEK Mandalika terhadap pertumbuhan ekonomi daerah di Kabupaten Lombok Tengah yang diukur dari Produk Domestik Regional Bruto (PDRB). Hasil penelitian ini menemukan bahwa dengan adanya KEK berdampak positif dan signifikan berkontribusi sebesar 1,485 persen terhadap pertumbuhan ekonomi meskipun perkembangan pembangunan KEK Mandalika sampai dengan akhir tahun 2022 masih 55 persen.

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In recent decades, tourism has become one of the most dynamic and fastest growing economic sectors in the world. The government issued an economic development policy which is also related to tourism development, namely the Special Economic Zones. One of the SEZs related to tourism development and one of the 5 Super Priority Destinations launched by the government is the Mandalika Special Economic Zone. Research on tourism SEZs on the economy in Indonesia is limited to qualitative studies and focuses more on industrial SEZs while tourism SEZs also have the potential to provide benefits.

Using district/city level data from 2000 to 2021, this study uses the synthetic control method to estimate the impact of the existence of the Mandalika SEZ on regional economic growth in Central Lombok Regency as measured by the Gross Regional Domestic Product (GRDP). The results of this study found that the existence of SEZs had a positive and significant impact contributing 1.485 percent to economic growth even though the development of the Mandalika SEZ until the end of 2022 was still 55 percent."