Hasil Pencarian  ::  Simpan CSV :: Kembali

"ABSTRAKStraight Wire Appliance (SWA) merupakan sebuah sistem perawatan ortodontiyang dirancang untuk memperoleh in-out, inklinasi dan angulasi akhir gigi-geligiyang ideal. Perbedaan sudut torque dan nilai preskripsi akan mempengaruhiinklinasi akhir gigi-geligi. Penelitian ini bertujuan untuk mengetahui akurasitorque braket MBT slot 0,022? yang beredar di Indonesia. Penelitian dilakukanmenggunakan SEM terhadap sudut torque antara basis braket dengan dasar slotbraket kaninus atas pada 3 produk ortodonti setelah diposisikan tegak lurus optik.Uji statistik menyatakan terdapat perbedaan signifikan antara braket Agile Abzil3M Unitek (-3,69°) dan Versaden (-3,85°) dengan preskripsi (-7°), namun tidakterdapat perbedaan signifikan antara braket Ormco (-7,68°) dengan preskripsi.

---

ABSTRACTStraight Wire Appliance (SWA) was designed to facilitateideal in-out, inclinationand angulation of the teeth. Variations between actual brackettorque valuesandprescription values are considered essential to providing proper tooth inclination.This study aims to determine the accuracy of the slot.022" MBT bracketsmarketed in Indonesia. The measurement was conducted using the SEM to thetorque angle between the base of bracket and slot. Statistical analysis indicatedsignificant differences between Agile Abzil 3M Unitek (-3.69°) andMBTprescription (-7°), as also Versaden (-3.85°).No significant differences foundbetween the Ormco bracket (-7.68°) and MBT prescription."

"To obtain a final occlusion, torque is needed to place the teeth in a precise labiolingual or buccolingual position. Biomechanically principles and arch manipulation is compulsory to produce torque movement. This paper discusses the technique to produce torque and its biomechanical principles. There are two kinds of torque, root torque and crown torque which can be done on anterior as well as posterior teeth by holding the crown in its position while applying a moment of a force on the rest, root torque can be obtained. In root torque, the center of rotation is at the incisal edge or at the bracket with a 12:1 moment to force ratio. Torque can be produced by using retrangular wire or using torquing auxiliaries. Torque movement is frequently needed in orthodontic treatment which needs a through understanding a biomechanical principles."

"Transmisi daya mekanik mengacu pada perpindahan energi mekanikal dari suatu komponen ke komponen lainnya. Terdapat berbagai macam metode untuk mentransmiskan daya secara mekanik, salah satu diantaranya adalah menggunakan coupling. Coupling adalah komponen yang menyatukan kedua poros antara sumber penggerak dan mesin yang digerakkan, terdapat dua macam tipe coupling yaitu flexible coupling dan rigid coupling. Flexible coupling bertujuan untuk memberikan kompensasi terhadap ketidaksejajaran yang terjadi antara kedua poros, dimana ketidaksejajaran dapat menimbulkan getaran yang berlebih pada komponen mesin. Sedangkan rigid coupling dapat mentransmisikan torsi yang lebih besar dibandingkan dengan flexible coupling. Salah satu coupling yang memadukan kedua karakteristik dari flexible coupling dan rigid coupling adalah gear coupling. Gear coupling terdiri dari dua komponen penghubung yang memiliki gigi eksternal dan gigi internal, kedua gigi akan saling terhubung dan mentransmisikan daya saat coupling bekerja. Diantara kedua gigi terdapat pelumas berupa gemuk yang menjaga gigi dari gesekan berlebih dan menghindari ke-ausan pada permukaan gigi. Pada industri manufaktur kertas gear coupling digunakan untuk memutar roll pada proses forming hingga proses dewatering kertas. Perubahan pada parameter mesin dapat menyebabkan terjadinya perubahan pada design awal pemilihan coupling. Pada case study berikut dapat dilihat bahwa perubahan parameter mesin dapat mempengaruhi lifetime coupling, bahkan dapat menyebabkan adanya lost time produksi mencapai 587 menit dalam setahun. Design awal dengan tipe coupling SSM 200 SEISA dengan maksimum torsi 6.750 N.M dengan besaran toleransi misalignment sebesar 1.5 mm, dengan memperhitungkan adanya perubahan parameter mesin seperti pertambahan kecepatan mesin dan usia mesin maka dilakukan perubahan tipe gear coupling menjadi HK 304 MOVENTAS dengan maksimal torsi sebesar 12.500 NM dan toleransi misalignment sebesar 1.8 mm. Setelah perubahan dilakukan tidak ada lagi kejadian lost time akibat dari gear coupling sehingga produksi dapat dimaksimalkan.

---

Mechanical power transmission refers to the transfer of mechanical energy from one component to another. There are various methods for transmitting power mechanically, one of which is through the use of a coupling. A coupling is a component that unites two shafts between the driving source and the driven machine. There are two types of couplings: flexible coupling and rigid coupling. The purpose of a flexible coupling is to compensate for misalignment that occurs between the two shafts, where misalignment can cause excessive vibration in machine components. On the other hand, a rigid coupling can transmit greater torque compared to a flexible coupling. One coupling that combines the characteristics of both flexible and rigid couplings is the gear coupling. A gear coupling consists of two connecting components that have external and internal teeth. The two teeth will connect and transmit power when the coupling is in operation. Between the two teeth, there is a lubricant in the form of grease that protects the teeth from excessive friction and prevents wear on the tooth surface. In the paper manufacturing industry, gear couplings are used to rotate rolls from the paper forming process to the paper dewatering process. Changes in machine parameters can cause changes in the initial design of the coupling selection. In the following case study, it can be seen that changes in machine parameters can affect the lifetime of the coupling, and can even cause lost production time of up to 587 minutes in a year. The initial design with the SSM 200 SEISA coupling type with a maximum torque of 6,750 N.M and a misalignment tolerance of 1.5 mm, considering changes in machine parameters such as increased machine speed and machine age, a change was made to the gear coupling type to HK 304 MOVENTAS with a maximum torque of 12,500 NM and a misalignment tolerance of 1.8 mm. After the change was made, there were no more lost time events due to the gear coupling, so production could be maximized."

"Motor induksi tipe sangkar tupai merupakan jenis motor listrik yang sering digunakan pada industri dan rumah tangga dikarenakan konstruksi yang kuat, tingkat kehandalan tinggi, dan perawatan mudah. Penggunakan motor induksi sudah meluas bukan hanya bidang industri dan rumah tangga tetapi juga dalam bidang transportasi, dikarenakan motor induksi tidak membutuhkan magnet permanen dan efisiensi relatif tinggi. Oleh karena itu penulis melakukan penelitian desain motor induksi 250 kW tipe sangkar tupai untuk memberikan alternatif pada kendaraan listrik.Penelitian ini dilakukan dengan merancang parameter-parameter yang dibutuhkan dalam desain motor induksi dan mensimulasikan di MotorSolve. Hasil simulasi kemudian dianalisa dan dioptimasi untuk mencapai spesifikasi yang diinginkan. Didapatkan hasil simulasi yang sudah mendekati spesifikasi motor induksi yang diinginkan.

---

Induction motor squirrel cage type is a type of electric motor that is often used in domestic and industrial construction due to strong, high level of reliability and easy maintenance. The use of an induction motor is widespread not only in industry and households but also in the fields of transport, due to the induction motor does not require permanent magnets and relatively high efficiency. Therefore, the authors conducted research design 250 kW induction motor squirrel cage type to provide an alternative to the electric vehicle.

This research was conducted by designing the parameters needed for induction motor design and simulate in MotorSolve. The simulation results are then analyzed and optimized to achieve the desired specifications. Obtained results of the simulation are already approaching the desired induction motor specifications in terms of power, efficiency, power factor, and torque. "

"This book investigates the utilization of harmonics in the permanent magnet (PM) or rotor shape to improve the torque density of PM brushless AC machines including three-phase inner rotor and outer rotor machines, five-phase machines, dual three-phase machines, linear machines, by means of analytical, finite element analyses, and as well as experimental validation. The torque density can be improved while the torque ripple remains low in PM shaping utilizing the 3rd harmonic. In this book, the analytical expression of output torque is derived for PM machines with rotor shape using the 3rd harmonic, and then the optimal 3rd harmonic for maximizing torque is analytically obtained. The book compares the PM shape in surface-mounted PM (SPM) machines and the rotor lamination shape in interior PM (IPM) machines utilizing the 3rd harmonic, and it becomes clear that their shaping methods and amount of torque improvement are different. In a five-phase PM machine, the 3rd harmonic can be utilized in both the current waveform and PM shapes to further improve the output torque. For the dual three-phase SPM machines without deteriorating the torque more than 30% when the optimal 3rd harmonic into both the current and PM shape are injected.The harmonics in airgap flux density have significant influence on the cogging torque, stator iron flux distribution, and radial force between the rotor and stator. These effects has been investigated as well in this book."

"The use of aj alcohol as a motor fuel received during the oil crises of the oil crises of the 1970 an due to its s availebul...."

"Metode kendali vektor telah menjadi alternatif utama dalam pengendalian motor induksi tiga fasa. Salah satu metode kendali vektor yang sering digunakan adalah metode kendali torsi langsung. Namun sistem ini memiliki kekurangan dengan adanya riak pada torsi yang besar. Penambahan duty ratio berbasis logika Fuzzy dapat memberikan unjuk kerja yang lebih baik bila dibandingkan dengan metode kendali torsi langsung konvensional. Dengan melakukan pengujian sistem kendali torsi langsung dan duty ratio dengan motor induksi tiga fasa kapasitas kecil, sedang dan besar, dapat dilihat pengaruh dari momen inersia terhadap putaran rotor. Pada tesis ini digunakan MATLAB SIMULINK untuk simulasi dengan tiga tipe motor, yaitu 1 HP, 10 HP dan 50 HP. Dengan parameter yang sama, dapat terlihat motor dengan nilai momen inersia besar memiliki putaran lebih stabil bila dibandingkan dengan motor yang memiliki momen inersia kecil.

---

Vector control has become the first alternative in control of three phase inductionmotor. One of the vector control method which is commonly used is a direct torque control method. However, this system has drawback as the existence of ripples at torque. The addition of duty ratio control base on Fuzzy logic can give better performance when compared to conventional direct torque control. By doing an examination on direct torque control and duty ratio with small, medium and big capacities of three phase induction motors can be shown the influence from moment inertia to rotor rotation. This thesis uses MATLAB SIMULINK for the simulation study with three types of motors, for example 1 HP, 10 HP and 50 HP. It is shown that using the same parameters, a motor with a larger moment inertia gives a better performance in comparison to a motor with smaller moment inertia."

"ABSTRAKTorsi cogging yang semakin besar akan meningkatkan kecepatan start-up dari sebuah turbin angin dan menghambat momen inersia. Pada akhirnya, akan mempengaruhi banyaknya energi yang dikonversi menjadi listrik. Oleh karena itu, skripsi ini menjabarkan sebuah metode untuk mereduksi torsi cogging pada GSMP dengan modifikasi pada permukaan inti gigi statornya. Modifikasi berupa pemberian cekukan dengan jumlah dan dimensi yang divariasikan untuk mendapatkan konfigurasi yang terbaik. Kemudian, setelah analisis berdasarkan torsi cogging tambahan yang tercipta dengan pemberian cekukan, dilakukan modifikasi lanjutan berupa pemberian tonjolan pada kedua pinggiran setiap inti gigi stator. Pada penelitian ini, digunakan perangkat lunak berbasis FEM (Finite Element Method) untuk mensimulasikan. Hasil simulasi menunjukkan, dengan hanya pemberian cekukan, reduksi torsi cogging mencapai 46.3% dengan efek samping berupa penurunan tegangan induksi sebesar 4.00%, dan penurunan THD (Total Harmonic Distortion) menjadi 11.97% dari sebelumnya 12.61%. Sedangkan, setelah penambahan tonjolan pada pinggiran setiap gigi inti stator, reduksi mencapai 66.1% dengan efek samping berupa penurunan tegangan induksi sebesar 1.16% dan peningkatan THD menjadi 12.68%.

---

ABSTRACTGreater cogging torque result in higher start-up speed of the wind turbine and also inhibit the inertia, which are both of them will affect the amount of energy that is converted into electricity. Therefore, this thesis proposes a method to reduce the cogging torque in PMSG, which is achieved by notches on the surface of the tooth stator core. The number and dimensions of the notches are considered as parameters which are modified in order to obtain the best possible configuration. Later on, an analysis based on the additonal cogging torque that is created by the notches, result in an idea to add two bulges on the edge of the tooth stator core and considered in this thesis as an advanced modification. The change in induction voltage and THD are also analyzed as side effects of the method that is proposed. In this research, FEM (Finite Element Method) software is used for the simulation. With notches, the simulation result shows 46.3% reduction of the cogging torque with 4.00% reduction of induction voltage and reduction of THD (Total Harmonic Distortion) to 11.97% from 12.61% at the initial model. While after adding two bulges on the edge of the tooth stator core, the cogging torque reduction reach 66.1% with only 1.16% reduction of induction voltage and increase in THD to 12.68%."

"ABSTRAKPenulisan ini membahas mengenai perancangan desain motor BLDC 12 slot dan 8 pole dengan kapasitas 40 kW menggunakan material komposit, dalam hal ini Somaloy, pada inti motor. Penelitian berfungsi untuk melihat pengaruh perubahan diameter stator, panjang stack, diameter rotor, ketebalan magnet, jumlah lilitan dan material yang digunakan untuk melihat perbandingan performa berdasarkan keluaran torsi, daya keluaran, dan faktor daya pada motor. Hasil penelitian didapatkan bahwa keluaran nilai torsi pada material Somaloy sebesar 97.9 Nm, daya keluaran mencapai 41 Nm, dan faktor daya sebesar 0.72. Simulasi tersebut menunjukan penggunaan bahan komposit pada inti motor mampu menghasilkan keluaran berupa torsi, daya keluaran, dan faktor daya yang cukup baik. Simulasi motor menggunakan software Finite Element Method FEM.

---

ABSTRACTThis research discusses about the design of BLDC motor 12 slots and 8 poles with a capacity of 40 kW using composite material, in this case is Somaloy, at its core. The research functioned to see the effect of stator diameter change, stack length, rotor diameter, magnet thickness, number of turns, and material used to see performance comparison based on torque output, output power, and power factor. The results obtained that the output value of torque on Somaloy material is 97.9 Nm, output power is 41 Nm, and power factor is 0.72. The simulation results show that the use of composite materials on the motor core is capable of producing good output such as torque output, output power, and power factor. Simulation software motor using Finite Element Method FEM."

"ABSTRAKTorsi cogging adalah torsi yang ada pada setiap generator magnet permanen, muncul karena adanya interaksi antara slot pada stator dengan medan elektromagnetik yang dihasilkan oleh magnet permanen pada rotor. Torsi ini menghambat kerja generator untuk menghasilkan daya listrik Penelitian ini memfokuskan pada reduksi torsi cogging pada generator magnet permanen dengan metode anti notch. Akibat adanya anti notch, maka dilakukan penurunan model matematik dari kerapatan fluks magnetik normal Bn = Bar dan kerapatan fluks magnetik tangensial Bt = Ba? . Persamaan torsi cogging yang baru berdasarkan perbedaan radius tepi dalam stator pada posisi-posisi tertentu. Validasi persamaan matematik melalui perhitungan dengan MATLAB dan FEMM. Metode anti notch efektif untuk menurunkan torsi cogging namun perubahan energi yang berhubungan dengan efisiensi tidak banyak berubah. Dengan penambahan anti notch maka nilai Bt turun sehingga torsi cogging minimal. Hasil torsi cogging yang didapatkan antara keduanya tidak persis sama nilainya, namun pola dan kecenderungannya sama, yaitu cenderung mendekati nol dan lebih stabil dibandingkan dengan model referensi. Persentase reduksi torsi cogging untuk model sederhana anti notch adalah 92,9 dan 97,03 . Eksentrisitas rotor yang diijinkan antara 0,5 sampai 1 derajat. Torsi cogging minimal akan memperhalus jalannya rotor, sehingga pada kecepatan angin rendah, rotor akan berputar untuk menghasilkan daya listrik

---

ABSTRACTCogging torque is the remaining torque of any permanent magnet generator, arising from the interaction between the stator slot and the electromagnetic field brought about by the permanent magnet on the rotor. This torque discourages the performance of the generator to generate electrical power. This research concentrates on reducing cogging torque on the permanent magnet generator by anti notch method. As a following of the anti notch, the mathematical model is derived from normal magnetic flux density Bn Bar and tangential magnetic flux density Bt Ba . The new cogging torque equation is based on the diversity in the edge radius in the stator at particular positions. Validate mathematical equations through computations with MATLAB and FEMM. An adequate anti notch method for reducing cogging torque but energy related changes in efficiency has not varied considerably. With the extension of anti notch thus the value of Bt down so that the minimum cogging torque. The result of the cogging torque achieved between the two is not precisely the same value, but the pattern and trend are the same, which tends to be near zero and further steady than the reference model. The percentage of cogging torque reduction for simple anti notch models is 92.9 and 97.03 . The permissible rotor permeability is between 0.5 to 1 degree. Minimum cogging torque will lighten the rotor course, so at moderate wind speeds, the rotor will rotate to generate electrical power."