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Pada pengujian seakeeping miniatur kapal cepat gerak zig-zag mengalami overshoot sebesar 13,5° melewati jalur yang telah ditentukan 20°, sehingga tidak terwujud konsistensi kestabilan kapal dan kemiringan arah sudut yang berakibat pada hasil pengambilan data. Pada penelitian ini berfokus pada pembuatan sistem kontrol otomatis untuk mengendalikan gerak rudder. Metode yang digunakan yaitu PID dengan tuning Ziegler-Nichols. Sistem ini menggunakan teenseyduino sebagai mikrokontroler untuk mengontrol dua servo motor sebagai rudder kapal, HWT 905 sebagai sensor dan motor DC sebagai laju kecepatan pada miniatur kapal cepat. Sensor HWT905 akan mendeteksi kemiringan arah pada badan kapal akibat gelombang. Berdasarkan hasil pengujian didapatkan parameter gain yang mampu memberikan hasil terbaik yaitu pada saat nilai Kp = 1,1, Ki = 3,3, Kd = 0,09, didapatkan nilai error steady state sebesar 15% dan overshoot sebesar 3°. Nilai rise time yang diperoleh sebesar 3 detik dan settling time diperoleh sebesar 5 detik yang menunjukkan bahwa gerak dari motor servo mulai stabil pada waktu tersebut.

Sextortion is one of the type of Online Gender Based Violence. It is an extortion by using the threat of distributing private photos or videos of victims with pornographic content, which intimidates the victim and fulfill the perpetrator's request. Therefore, the purpose of this study is to find out the qualification of sextortion which has implication as a criminal act. It also to find out the criminal responsibility of the perpetrator and to analyse the verdict of the related cases. This study uses the normative legal method which employs Statute Approach and Case Approach. This study concludes that the criminal qualifications of sextortion can be punished using the Criminal Code, the ITE Law and the Pornography Law. However, more specific regulations are still needed considering that the characteristics of the sextortion are actually different from those of the criminal act of extortion in general. Keywords: Online; Sextortion; Violence; Gender; Extortion. Abstrak “Sekstorsi” yaitu salah satu Kekerasan Berbasis Gender Online (KBGO) yang merupakan suatu perbuatan pemerasan dengan menggunakan ancaman menyebarkan foto atau video korban yang memiliki muatan pornografi yang menyebabkan korban takut dan memenuhi permintaan pelaku. “Sekstorsi” belum dikualifikasikan sebagai tindak pidana yang berbeda dengan pemerasan biasa. Peraturan perundang-undangan yang terkait dengan perbuatan pelaku “sekstorsi” belum diatur secara menyeluruh. Penulisan skripsi ini bertujuan untuk mengetahui perbuatan yang dilakukan oleh pelaku “sekstorsi” tersebut dapat dikualifikasikan sebagai tindak pidana dan pertanggungjawaban pidana pelaku “sekstorsi” dan memahami putusan kasus terkait. Penelitian ini adalah penelitian yuridis normatif, dengan pendekatan perundang-undangan dan pendekatan Kasus. Penelitian ini menyimpulkan bahwa kualifikasi tindak pidana dari perbuatan “sekstorsi” dan pertanggungjawaban pelaku “sekstorsi” telah dapat dapat dipidana dengan menggunakan KUHP, UU ITE dan UU Pornografi. Namun masih diperlukan peraturan yang lebih khusus mengingat karakteristik “sekstorsi” yang sebenarnya berbeda dengan bentuk tindak pidana pemerasan pada umumnya. Kata Kunci: Online; “Sekstorsi”; Kekerasan; Gender; Pemerasan.

A shortcoming of distance learning is the lack of substantive integration of hands-on activities into online classrooms. We conducted a research and development study, where the lab kits and tutorial videos were sent to students to perform experiments in their own homes. We planned, tested, developed, improved, and implemented kits into experimental distance learning. This research was conducted to improve previous studies in linear subjects. Findings have implications for distance learning in rural areas that have limitations. Furthermore, our findings illustrate the potential amplifying effect of this learning environment configuration for science teachers. Thirty-two students, four experts, and three science teachers participated in this research. The product’ validity and feasibility were obtained by descriptive analysis of experts and students' assessment data. Students’ learning motivation and activities were observed and analyzed descriptively. Students’ cognitive learning outcomes were obtained by analyzing pretest and posttest data using paired sample t-test. This learning helped students achieve intellectual goals by significantly improving students’ learning motivation, activities, and cognitive outcomes.

Li-ion capacitors (LIC) have emerged as a promising hybrid energy storage system in response to increasing energy demands. However, to achieve excellent LIC performance at high rates, along with cycling stability, an alternative anode to graphite is needed. Porous high-surface-area carbons, such as onion-like carbons (OLCs), have been recently found to hold high potential as high-rate-capable LIC anodes. However, a systematic understanding of their synthesis route and morphology is lacking. In this study, OLCs prepared from self-made metal organic frameworks (MOFs) Fe-BTC and Fe-MIL100 by a simple pyrolysis method were compared to OLCs obtained via high-temperature annealing of nanodiamonds. The LICs with OLCs produced from Fe-BTC achieved a maximum energy density of 243 Wh kg−1 and a power density of 20,149 W kg−1. Furthermore, excellent capacitance retention of 78% after 10,000 cycles was demonstrated. LICs with MOF-derived OLCs surpassed the energy and power density of LICs with nanodiamond-derived OLCs. We determined the impact of the MOF precursor structure and morphology on the resulting OLC properties, as well as on the electrochemical performance. Thus, MOF-derived OLCs offer significant potential toward high-performance anode material for LICs, enabling control over structure and morphology, as well as easy scalability for industrial implementation.

To develop seaplanes as a means of inter-island transportation, it is necessary to have a simulation, testing, and analysis of force measurements that work so that the aircraft can be designed optimally in terms of function and safety. To fulfill one type of test, the seaplane floater model is pulled in the Towing Tank to determine the hydrodynamic forces acting on the floater which include resistance (Fx), side force (Fy), lift force (Fz), and moments in all three axes. A method of measuring the force of 6 axis force and moment or 6 degrees of freedom (6 Degree of Freedom, 6 DOF) was built and designed by combining several single load cells so that these forces can be known optimally. From the results of the 6 DOF transducer design, it is proven that it can be used well in measuring 6 forces and moments with force measurement errors ranging from 1.38%. The distance between the 6 DOF transducer capture point and the floater force capture point will affect the measured moment transformation.

Pengukuran performa poros (torsi) kapal merupakan salah satu cara yang dapat digunakan untuk menghitung atau mengetahui performa dari mesin kapal. Pengukuran performa ini dilakukan pada saat mesin dan poros kapal belum dipasang atau dalam keadaan kapal baru. Untuk pengukuran performa (torsi) poros kapal pada saat kapal sudah berlayar lama tidak bisa dilakukan dengan menggunakan metode seperti pada saat mesin dan poros dalam keadaan baru. Terdapat beberapa kesulitan yang menyebabkan metode ini sulit untuk dilakukan terutama untuk mengukur torsi yang bekerja pada poros kapal. Hal ini disebabkan oleh minimnya ruang untuk melakukan pengukuran pada poros kapal. Salah satu metode yang dapat digunakan adalah melakukan pengukuran performa poros (torsi) kapal adalah menggunakan peralatan yang bernaman Shaft Power Measurement. Dengan peralatan ini maka dapat diketahui torsi, kecepatan dan daya yang bekerja pada poros (shat horse power/SHP) untuk nantinya diturunkan menjadi daya yang bekerja pada mesin kapal (effective horse power/EHP). Hasil yang didapatkan dari pengukuran torsi pada poros kapal adalah untuk mesin 1 dengan gearbox 1 mempunyai daya efektif (EHP) sebesar 822.56 HP dan untuk mesin 2 dengan gearbox 2 mempunyai daya efektif (EHP) sebesar 659.61 HP

Autopilot mode in the ship navigation system is intended to assist the work of the captain in controlling the ship, but the autopilot mode still has some disadvantages such as in the case of maneuvers to avoid collisions. Many studies on design of anti-collision design. But almost all use a numerical approach. In this paper will be discussed the design of maneuver controls that will be used on the ship model to avoid the ship from the collision. Where within the control system there are several sensors, including ultrasonic sensors, gyro sensors and Qualysis cameras. From ship model testing conducted, the design of maneuver control proved able to avoid the ship from the occurrence of collisions. Minimum distance of ship and obstacle at 250 m distance is 34,17 m, at a distance of 200 m is 13,46 m while at a distance of 150 m is 13,36 m.

Roll damping sangat berperan penting pada maksimum roll terutama pada daerah resonansi disekitar roll natural period. Dalam prediksi gerak roll, prediksi roll damping dilakukan dengan metode difraksi radiasi yang menambahkan viscous roll damping dari formulasi semi empiris maupun dari uji roll decay. Pada uji roll decay akan didapatkan koefisien komponen roll damping linier dan quadratik yang selanjutnya diperlukan dalam perhitungan nilai roll damping. Nilai koefisien roll damping ini bisa diperoleh dengan melakukan fitting hasil uji roll decay dengan metode Froude maupun Bertin. Pada studi ini dilakukan analisa terhadap perubahan roll damping dan akibatnya terhadap gerak roll pada dua buah model FPU barge yang identik namun berbeda dimensi. Perubahan dimensi model benda apung akan menimbulkan perubahan pula pada karakteristik koefisien linier maupun quadtatik roll dampingnya. Dari hasil pengujian model diketahui bahwa pengurangan dimensi panjang model dengan posisi relatif titik berat dan jari-jari girasi roll tetap akan menaikan nilai koefisien roll damping 21% dari desain induknya. Kenaikan nilai koefisien roll damping didominasi oleh komponen linier. Dengan adanya kenaikan koefisien roll damping pada model yang lebih pendek menyebabkan turunnya nilai respon gerak roll melalui uji seakeeping.

Sn-based alloys are potential candidates for replacing graphite as the anode material in Li-ion batteries (LIBs) due to their high theoretical electrochemical capacities. The second element in Sn alloys can be redox-active, contributing to the total electrochemical capacity, or nonactive, acting as a buffer for the volume change of the electrode caused by Li insertion/removal. In this study, we provide a straightforward technique for synthesizing Ni3Sn2 and Cu6Sn5 intermetallic materials by chemically dealloying ternary Al-Cu-Sn and Al-Ni-Sn alloys. In these alloys, Ni and Cu do not form any alloys with Li. Cu6Sn5 has a second-cycle charge capacity of approximately 900 mA h g−1 in Li batteries at a current density of 0.1 A g−1, and the capacity subsequently decreases to 340 mA h g−1 after 100 cycles. Although the nanoporous Ni3Sn2 anode initially has a lower charge capacity of 371 mA h g−1, its cycling behavior becomes considerably more stable after 100 cycles, with a capacity of 347 mA h g−1 at the same current density. Despite the fact that the capacity of Ni3Sn2 is lower than that of Cu6Sn5 at current densities below 2 A g−1, it preserves a capacity of more than 150 mA h g−1 at current densities of 5 and 10 A g−1. This result may be explained by the consistent pore distribution of Ni3Sn2 and its particles' larger specific surface area of 19 m2 g−1, resulting in better electron and ion transport.

Telah dilakukan penelitian untuk mengetahui bagian-bagian lamun Cymodocea sp. yang berpotensi sebagai antioksidan dan uji toksisitasnya. Ekstrak daun dan batang Cymodocea sp. dibuat dengan cara maserasi menggunakan tiga macam pelarut, yaitu metanol, etil asetat, dan n-heksan. Pengujian kadar total fenol menggunakan metode Follin-Ciocalteu. Aktivitas antioksidan dilakukan dengan metode spektrofotometri menggunakan DPPH ( 1,1-diphenyl-2-picrylhydrazyl ) sedangkan kadar toksisitas dilakukan dengan uji BSLT ( Brine Shrimp Lethality Test ). Hasil penelitian menunjukkan bahwa ekstrak metanol daun Cymodocea sp. mempunyai kandungan total fenol paling tinggi (26,73 mg GAE/gram ekstrak) dengan aktivitas antioksidan (IC 50 ) sebesar 518,57 ppm. Berdasarkan nilai IC 50 , sampel tersebut tergolong antioksidan lemah. Hasil uji toksisitas menunjukkan semua sampel Cymodocea sp. bersifat toksik terhadap larva udang Artemia salina Leach. Ekstrak etil asetat daun Cymodocea sp. mempunyai toksisitas terbesar dengan nilai LC 50 sebesar 67,14 ppm. Uji fitokimia menunjukkan bahwa ekstrak Cymodocea sp. mengandung senyawa golongan saponin, steroid, flavanoid, fenol hidrokuinon, dan terpenoid.

Pada uji free running dan turning circle maneuver , pergerakan model kapal perlu dikendalikan oleh operator menggunakan remote control . Kecepatan pergerakan maju mundur model kapal ditentukan oleh thrust akibat putaran propeller . Sedangkan perubahan heading model kapal ditentukan oleh sudut kemudi rudder . Perancangan sistem kendali ini dimaksudkan mengolah inputan kecepatan propeller dan sudut kemudi rudder yang ditentukan oleh operator melalui remote control . Pengolahan inputan tersebut menggunakan aplikasi berbasis software NI LabVIEW FPGA yang di- embedded kedalam controller cRio 9012 National Instruments. Output dari controller berupa sinyal digital PWM dengan duty cycle tertentu untuk menggerakkan motor DC yang memutar propeller dan menggerakkan motor DC lainnya untuk mengubah sudut rudder .

Young men nowadays have few interest with traditional art, including many kinds of Indonesia musical instruments. Compared with that traditional art, people are more familiar with multimedia application in computer devices. Based on those things, there is an idea to create a computer application to make famous Indonesia musical instruments by giving explanation and make a simulation. The application’s name is “Gandara”, a word from sanskrit language that means notes collection. “Gandara” uses MultiPoint Mouse SDK that makes the application to be able played by multiple users. The application is developed using Multimedia Development Life Cycle (MDLC) that consist of concept, design, material collecting, assembly, testing and distribution. “Gandara” users can learn both of gamelan and angklung by reading the explanation or playing the simulation. With this applicaton, users don’t need to face gamelan and angklung directly when they want to exercise. All of “Gandara” functions can work well when tested with black-box method and got positif results when tested by users.

Hydrous ruthenium oxide (RuO2 · nH2O) nanoparticles with various particle sizes and water contents were synthesized in sub- and supercritical water in a very short reaction time of 15 min. The particle size, surface area, morphology, crystalline structure, and electrochemical properties were analyzed and compared with those of commercial RuO2 particles. Ultrafine spherical RuO2 · 0.6H2O nanoparticles with an average size of 4.2 nm were produced in subcritical water (250°C, 300 bar), while larger and more highly crystalline rod-shaped RuO2 · (0.3–0.5)H2O particles were produced in supercritical water (400°C, 300 bar). The use of NaOH under the supercritical water conditions resulted in a decrease in particle size. The hydrous RuO2 nanoparticles synthesized in subcritical water exhibited a much higher specific capacitance (255 F g−1) at a scan rate of 10 mV s−1 than those synthesized in supercritical water (77 F g−1) and commercial RuO2 (8 F g−1).

Hierarchically porous anatase titanium oxide (TiO 2 ) microspheres were synthesized using a green supercritical methanol route over a very short reaction time of 15 min without using templates or surfactants. Primary nano-sized particles with diameters of 20–55 nm with organic coverage on the surface were loosely aggregated and formed secondary micron-sized particles 1.0–2.5 μm in diameter, creating a porous structure with average pores 9–15 nm in diameter. When the as-synthesized microspheres were calcined under a Ar/5% H 2 condition, carbonization of the organic groups formed an ultrathin and uniform carbon layer on the nano-sized primary particles with a thickness of 0.5–1 nm and reduced some of the Ti 4+ to Ti 3+ . Both the hierarchically porous structure and the conductive layer coating had positive effects by increasing Li ion storage capacity. The prepared TiO 2 microspheres exhibited a high reversible discharge capacity of 212.3 mA h g −1 at 0.1 C, a high-rate performance of 77.9 mA h g −1 at 8 C, and an excellent capacity retention of >97% at the end of 100 cycles at 1.0 C, whereas TiO 2 nanoparticles without porous structure and surface modification exhibited lower discharge capacities of 161.8 mA h g −1 at 0.1 C and 5.2 mA h g −1 at 8 C, and poorer capacity retention of 26%. The considerable improvement in the electrochemical performance was attributed to the nano-sized TiO 2 primary particles, porous structure, and carbon coating and Ti 3+ incorporation.

In water electrolysis, a major obstacle is the anodic reaction for water oxidation where substantial energy loss occurs mainly due to the large overpotential. Therefore, the electrocatalytic material of an anode is of importance to achieve a highly efficient water splitting reaction. Among the various requirements, the surface area of electrocatalysts has been considered a key factor in electrocatalytic reactions. In this study, to obtain a high surface area RuO2 electrocatalyst, a supercritical hydrothermal synthetic method was applied. Indeed, RuO2 particles with the surface area of 78.2 m2/g were successfully synthesized, which is 7 times higher compared with the commercial version. We also investigated the electrocatalytic activity of the synthesized high surface area RuO2 by evaluating the number of active sites and hydrogen production rates and compared them with the commercial one as a reference. Based on the cyclic voltammetric measurements, the number of active sites was estimated to be 152.1 mC cm−2 and 17.0 mC cm−2 for the synthetic and the commercial RuO2, respectively. More importantly, the hydrogen production rates measured by the water splitting device with RuO2 films for the anode showed 4 times higher value for the synthetic RuO2 compared with the commercial one.

Kendali manuver kapal untuk menghindari tabrakan menjadi masalah penting pada sebagian besar sistem transportasi kapal. Banyak kajian yang dilakukan agar kapal dapat terhindar dari tabrakan. Tetapi semuanya menggunakan pendekatan numerik. Pendekatan numerik memiliki kelemahan yaitu nilai yang diperoleh adalah nilai hampiran dan bukan nilai exact. Oleh karena itu perlu dilakukan kajian kendali manuver kapal menggunakan pendekatan pengujian skala model. Pada paper ini akan dibahas perancangan kendali manuver yang akan digunakan pada model kapal untuk menghindarkan kapal dari tabrakan. Dimana didalam sistem kendali tersebut terdapat beberapa sensor, antara lain sensor ultrasonic, sensor gyro dan kamera Qualysis. Pengujian dilakukan di kolam Manuvering Ocean Basin milik Balai Teknologi Hidrodinamika (d/h LHI), BPP. Teknologi. Model kapal yang digunakan adalah kapal patroli cepat (fast patrol boat). Halangan yang dipasang berjumlah 1 dan dalam posisi diam. Dari pengujian model kapal yang dilakukan, perancangan kendali manuver terbukti mampu menghindarkan kapal dari terjadinya tabrakan. Jarak minimum kapal dan halangan pada jarak tabrakan 250 m sebesar 88,25 m, pada jarak tabrakan 200 m sebesar 47,33 m sedangkan pada jarak tabrakan 150 m sebesar 12,75 m.