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"Saat ini banyak sekali peralatan rumah tangga yang menggunakan teknologi inverter untuk meningkatkan efisiensi energi. Namun setelah diteliti oleh para ilmuwan, penggunaan teknologi ini dapat menimbulkan gangguan pada rentang frekuensi 9-150 kHz. Hotel sebagai tempat pengoperasian beberapa peralatan, memiliki sistem instalasi tenaga listrik seperti soket listrik, ruang panel dan panel lantai. Gangguan yang ditimbulkan oleh setiap peralatan rumah tangga pada frekuensi 9-150 kHz menghasilkan karakteristik yang berbeda. Karakteristik yang berbeda juga akan terjadi jika pengukuran dilakukan pada tiga titik berbeda pada sistem instalasi listrik. Penelitian ini berfokus pada karakteristik rentang frekuensi gangguan 9-150 kHz yang ditimbulkan oleh peralatan rumah tangga. Dalam penelitian ini penyedot debu digunakan sebagai perangkat sumber gangguan. Dalam studi ini, dua jenis penyedot debu yang digunakan. Mereka memiliki kekuatan yang berbeda dan model yang berbeda tetapi mereka adalah merek yang sama. Ada 2 jenis mode yang digunakan di setiap vakum, yaitu mode tanpa beban dan mode beban penuh. Dengan menggunakan Picoscope untuk melihat dan merekam gangguan, maka diperoleh data gangguan dengan metode FFT di Matlab, diperoleh karakteristik gangguan pada frekuensi 9-150 kHz.Berdasarkan hasil penelitian, terdapat perbedaan nilai gangguan dan frekuensi antara tidak ada penyedot debu dengan saat ada penyedot debu. Jika tidak ada penyedot debu, didapatkan gangguan pada frekuensi 50 kHz pada 3 titik pengukuran yaitu soket, panel ruang dan panel lantai. Sedangkan pada penyedot debu, didapatkan gangguan pada frekuensi 11-16 kHz. Di mana frekuensi 11 kHz disebabkan oleh perawatan penyedot debu tipe B tanpa mode beban, frekuensi 12 kHz disebabkan perawatan penyedot debu tipe A tanpa mode beban, frekuensi 13 kHz disebabkan oleh perawatan penyedot debu tipe B dengan mode beban penuh, frekuensi 16 kHz disebabkan perawatan penyedot debu tipe A dengan mode beban penuh.

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Nowadays there are so many household appliances use inverter technology to improve energy efficiency. However, after being investigated by scientists, the use of this technology can cause interference in the frequency range 9-150 kHz. The hotel as a place to operate several equipment, has an electric power installation system such as electric sockets, panel rooms and floor panels. Interference caused by each household appliance at a frequency of 9-150 kHz produces different characteristics. Different characteristics will also occur if measurements are made at three different points in the electrical installation system.

This study focuses on the characteristics of the frequency range of interference from 9-150 kHz caused by household appliances. In this study, a vacuum cleaner was used as a source of interference. In this study, two types of vacuum cleaners were used. They have different strengths and different models but they are the same brand. There are 2 types of modes used in each vacuum, namely no-load mode and full-load mode. By using the Picoscope to view and record the disturbance, the disturbance data obtained by the FFT method in Matlab, obtained the disturbance characteristics at a frequency of 9-150 kHz.

Based on the research results, there is a difference in the value of the disturbance and frequency between the absence of a vacuum cleaner and when there is a vacuum cleaner. If there is no vacuum cleaner, interference is obtained at a frequency of 50 kHz at 3 measurement points, namely the socket, room panel and floor panel. Whereas in the vacuum cleaner, interference is obtained at a frequency of 11-16 kHz. Where the frequency of 11 kHz is due to the treatment of the type B vacuum cleaner without load mode, the frequency of 12 kHz is due to the maintenance of the type A vacuum cleaner without load mode, the frequency of 13 kHz is due to the maintenance of the type B vacuum cleaner with full load mode, the frequency of 16 kHz is due to the maintenance of the vacuum cleaner type A dust with full load mode."

"Computer simulation program has been developed on the basis of Liapunov approach for the study of MRAC technique applied to pressure control for a vacuum system. Both proportional and integral feedback as well as disturbance feedforward is considered in the closed-loop system. The simulation result obtained with a personal computer demonstrates that this MRAC technique is feasible and provides effective and satisfactory control despite its poor initial control policies and wide range of choice for the adaptive gains. For a series of step disturbance, MRAC resulted in continually improved control with very good agreement obtained between process and reference model responses after the second disturbance."

"A vacuum drying system is being designed and developed at National Institute of Vacuum Science & Technology (NINVAST) to dry various materials under vacuum conditions. Its performance and capabilities are tested by carrying out different experiments on green (freshly cut) wood samples of Poplar and Eucalyptus with dimensions of 990.6 mm x 76.2 mm x 25.4 mm and 469.9 mm x 50.8 mm x 25.4 mm, respectively. These samples were dried from green moisture content (MC) 78% to 10% by this system at ultimate vacuum of about 1.6 x 103 pascal and at a temperature ranging from 35oC to 55oC for about 20 hrs. Drying quality tests included: prong test, warp measurement, surface checking and moisture content measurement, which were all performed. The resulting wood samples showed no dislocation and no excessive stress buildup. If compared to ordinary drying process, the vacuum drying is rapid and the drying rate increases with rise in temperature. The designed system is beneficial for commercial use."

"Terdapat permasalahan berkaitan dengan ketersediaan air tawar di seluruh dunia. Terlepas dari fakta bahwa 70% Bumi terdiri dari air, hanya 2,53% darinya adalah air tawar, dan hanya 0,36% darinya dapat diakses. Situasi semakin memburuk karena pertumbuhan populasi dan kebutuhan air yang melampaui kapasitas eksploitasi. Fokus penelitian ini adalah solusi untuk desalinasi air laut. Teknologi ini menghasilkan air tawar dengan efektif melalui proses penguapan dan kondensasi. Pemanfaatan teknologi ini berfokus pada daerah terpencil yang memiliki keterbatasan dalam pasokan energi listrik. Salah satu inovasi baru adalah penggabungan dengan Direct Spray Evaporator untuk meningkatkan temperatur air laut dan efisiensi desalinasi.Penelitian dan perancangan ini dilakukan dengan tujuan untuk membuat prototipe dan meningkatkan performa dari sistem solar still untuk menghasilkan air tawar. Penelitian ini dilakukan dengan memvariasikan beberapa faktor atau variabel, seperti feed water temperatur pada 50oC, 55oC, 60oC, 65oC, 70oC, dan 80oC; feed water flowrate pada 0,4 LPM, 0,5 LPM, dan 0,6 LPM; vacuum pressure pada -0,4 bar, -0,5 bar, dan -0,6 bar; dan cooling water temperatur pada 25oC, 27oC, dan 29oC. Beberapa variasi tersebut dibuat untuk mengetahui pengaruh dari masing-masing variabel terhadap destilate productivity dan menentukan kondisi optimal dari pengoprasian solar still desalination. Performa kinerja solar still paling efektif dicapai pada temperatur air umpan 80°C, laju aliran 0,6 LPM, tekanan vakum -0,6 bar, temperatur air pendingin 29°C dengan laju aliran 1,4 LPM, menghasilkan 0,22 liter air destilat, recovery rate 0,61%, specific energy consumption 57092,39 kJ/L, dan efisiensi termal 66,63%, menunjukkan potensi tinggi sistem ini.

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There is a problem related to the availability of fresh water throughout the world. Despite the fact that 70% of the Earth consists of water, only 2.53% of it is fresh water, and only 0.36% of it is accessible. The situation is getting worse due to population growth and water needs that exceed the exploitation capacity. The focus of this research is a solution for seawater desalination. This technology produces fresh water effectively through the process of evaporation and condensation. The use of this technology focuses on remote areas that have limited electricity supply. One of the new innovations is the combination with Direct Spray Evaporator to increase seawater temperatur and desalination efficiency.

This research and design were carried out with the aim of making a prototype and improving the performance of the solar still system to produce fresh water. This research was carried out by varying several factors or variables, such as feed water temperatur at 50oC, 55oC, 60oC, 65oC, 70oC, and 80oC; feed water flowrate at 0.4 LPM, 0.5 LPM, and 0.6 LPM; vacuum pressure at -0.4 bar, -0.5 bar, and -0.6 bar; and cooling water temperatur at 25oC, 27oC, and 29oC. Several variations were made to determine the effect of each variable on distillate productivity and determine the optimal conditions for operating solar still desalination. The most effective solar still performance was achieved at a feed water temperatur of 80°C, a flow rate of 0.6 LPM, a vacuum pressure of -0.6 bar, a cooling water temperatur of 29°C with a flow rate of 1.4 LPM, producing 0.22 liters of distillate water, a recovery rate of 0.61%, a specific energy consumption of 57092.39 kJ/L, and a thermal efficiency of 66.63%, indicating the high potential of this system."

"ABSTRAKVacuum lifter merupakan suatu alet yang dlgunakan sebagal materlal handling dengan prinsip udara vacuum. Tujuan digunakannya alat lni adalah agar benda yang ditangani, dalam hal ini paper-roll tidak mengalamlipenurunan kualltas, sebagaimana dltemul pada penggunaan material handling yang Ialn. Selain ltu dalam penggunaannya pada warehouse, vacuum lifter lni dapat dipasang pada overhead crane yang memungkinkan dicapainya pemakaian area warehouse seoptimum mungkin.Selanlutnya dalam Skripsi lni penulls akan membahas prinsip kerja vacuum lifter dan juga akan merancang mekanisme vacuum lifter dengan membuat rangkalan skematis sistem pneumatis vacuum lifter. Dan berdasarkan data-data yang didapat, baik darl PT. X selaku lndustri pembuat kertas, maupun brosur-brosur mengenal vacuum lif-ter, penulls juga akan melakukan beberapa perhitungan untuk melengkapi perancangan alat lni, antara Iain: menentukan besar tekanan vacuum minimum yang harus dicapai, menentukan besarnya daya yang dlperlukan kompresor dan vacuum pump, dan merencanakan dlmensi dari pressure air tank."