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"The advantages optical fiber in communication field are widely utilized in developing steps from electrical communication to optical communication. Optical fiber communication promise extremely high data rate over long distance transmission without needing to amplify and retransmit along the way. It is well understood that if frequency of the transmitted signals. is increased some problems such as electromagnetic interferences. crosstalk and signal distortions will appear. Those difficulties can. be solved or eliminated by using optical fiber cable. instead of copper cable.Optical fiber used to transmit and to receive information signal mutinously was usually separated in difference fibers for transmitting and receiving direction. I n this thesis a bi-directional transmission system through a single fiber with same wavelength by the use of rod lenses was constructed. A simple circuit design techniques have been used in order to make transmitter and receiver. To combine and to separate transmitter and receiver in each side to and from the fiber, two quarter-pitch GRIN rod lenses functioning as optical directional coupler was used.The result of the experiment as a model of bi-directional optical communication system shows a good performance with an appropriate reliability. The measurement results of power distribution loss. crosstalk and signal transmission quality that have been evaluated to conclude the entire result."

"Concerning with the local low capability in producing and manufacturing the Power sector components and equipment, in Contrast, in PJP-II (the second phase of national long term development) this mentioned infrastructure will be progressively developed. For this purpose a wide research program on power sector components and equipment should be carried out in the University of Indonesia for strengthening the engineering and manufacturing capability of the industries in the power sectors especially the medium and small scale Industries (SA/fl). The first phase of the study will focus on the prototype design, fabrication method and procedures and mechanical performance testing of 500 KV transmission line spacer damper. In this study, the mechanical testing on the prototype spacer damper will consist of structural static and fatigue test, Test on rubber part and damping study, In the next phase for complete prototyping, high voltage electrical testing (corona testing) will be also conducted."

"Pada industri otomotif, sistem transmisi kopling ganda sering digunakan pada kendaraan roda empat yang berperforma tinggi. Hal tersebut karena sistem transmisi kopling ganda memiliki respon yang cepat dalam perpindahahan gigi, interupsi traksi yang minim, serta efisiensi bahan bakar. Sistem transmisi kopling ganda prinsipnya adalah dua sistem transmisi manual yang dipisahkan oleh dua kopling untuk set gigi ganjil dan genap. Salah satu permasalahan utama yang dihadapi sistem transmisi kopling ganda adalah kerumitan perancangan sistem kendali mengingat sifatnnya yang non-linear dan adanya kopling antar komponennya sehingga diperlukan penganganan khusus dalam perancangan sistem kendali kopling ganda. Pada penelitian ini digunakan perangkat lunak simulasi powertrain Amesim dengan skema pengendalian prediktif berbasis data untuk mengendalikan fasa inersia sistem transmisi kopling ganda yaitu saat kopling yang akan terkait menyesuaikan kecepatan dengan kecepatan mesin sesuai lintasan yang sudah ditetapkan. Pengendalian yang tidak baik pada fase ini akan memperbesar sentakan jerk perpindahan gigi yang memengaruhi kenyamanan penumpang, performa, dan efisiensi bahan bakar.

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In automotive industry, dual clutch transmission or DCT usually used by high performance car. Thats because DCT have a quick response in gearshift, low traction interuption, and good fuel efficiency. In principle, dual clutch transmission is two set of manual transmission combined and separated two gear set odd and even. Gearshift process performed with disengaging off going clutch and engaging on going clutch based on powertrain angular velocity and torque. This process ussualy called clutch to clutch shift. One major chalenge on dual clutch transmission is its complexity control system design due to its nonlinearity and coupling between its component properties so that need special treatment on designing its control system.

In this research, author will simulating data driven model predictive control for inertia phase on dct gearshift with Amesim powertrain simulation software. Inertia phase is occur when on going clutch angular speed syncronized with engine angular speed until the slip between them is zero. With that controller, the trajectory of slip is defined and system will follow that trajectory. If the controller on this phase is not good, jerk will incrase so that pessenger comfort is reduced in addition fuel efficiency will decrease. "

"Sistem Transmisi yang baik sangat dibutuhkan bagi sebuah kendaraan untuk mendapatkan tingkaat efisiensi dan efektifitas terbaik dari transfer energi yang terjadi pada powertrain. Sistem transmisi kopling ganda merupakan teknologi yang banyak memikat perhatian, dimana teknologi transmisi ini dapat melakukan perpindahan gigi dengan cepat namun dengan tingkat kenyamanan seperti sistem transmisi otomatis. untuk dapat mencapai performa terbaik dari sistem transmisi kopling ganda, dibutuhkan pengendalian yang baik pada fasa inersia, dimana terjadi banyak perpindahan torsi dan juga perbedaan kecepatan angular dari mesin dengan kopling. Namun pada aplikasinya, sistem transmisi kopling ganda merupakan sistem dengan tingkat nonlinearitas yang sangat tinggi dan merupakan sistem yang kompleks. Pada penelitian ini diajukan sebuah sistem kendali nonlinear dengan menggunakan metode backstepping untuk dapat menghadapi tantangan pengendalian sistem transmisi kopling ganda khususnya pada fasa inersia.

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Good transmission system is needed for a vehicle to get the best efficiency and effectivity performance for energy transfer that occurs in the powertrain systems. Dual Clutch Transmission lately attract lots of attention from researchers and industry, because of its ability to shift gear in a very short moment with high convenience as an automatic transmission vehicle. To achieve its best performance, a good controller is needed especially in inertia phase, which occurs lots of torque transfer and also a high difference of angular velocity of engine and clutch. Unfortunately, in the application, dual clutch transmission is a high nonlinear system and also a very complex system. In this thesis, a nonlinear controller with backstepping method is proposed to overcome this control problem for dual clutch transmission at inertia phase. "

"Kebutuhan akan layanan data saat ini semakin meningkat karena penggunaan smartphone untuk media sosial, layanan online, dan akses internet meningkat secara signifikan. Operator Jaringan Seluler/MNO (Mobile Network Operator) berusaha menyeimbangkan kebutuhan tersebut dengan meningkatkan penyebaran pemancar /BTS (Base Transceiver Station) yang mendukung layanan data dengan mengimplementasikan teknologi 4G. Sesuai dengan distribusi lokasi BTS, maka diperlukan transmisi antar BTS ke jaringan inti/core network. Tanpa jaringan transmisi dengan kapasitas yang cukup besar, penggelaran BTS 4G tidak akan ada artinya.Tersebarnya beberapa jaringan transmisi tentunya akan menimbulkan kebutuhan investasi yang besar. Pemilihan teknologi yang digunakan, desain dan skema pemilihan pengadaan merupakan hal penting agar investasi saat ini dan beberapa tahun mendatang dapat optimal.Penelitian ini menganalisis pemilihan strategi terbaik yang dapat diterapkan oleh Operator Jaringan Seluler dalam menggelar transmisi jaringan akses yang menghubungkan BTS 2G/3G/4G ke jaringan core/inti. Dalam hal ini area yang dipilih adalah cluster Denpasar Bali pada jaringan seluler operator PT.XYZ. Analisis pemenuhan kebutuhan bandwidth pada awalnya dilakukan dengan menganalisis trafik data di kota Denpasar Bali, kemudian dengan analisis trend ditentukan estimasi kebutuhan bandwidth dalam beberapa tahun ke depan. Dimensioning didefinisikan untuk memenuhi kebutuhan kapasitas per site. Berdasarkan dimensioning tersebut, kebutuhan bandwidth dipenuhi dengan beberapa alternatif skenario. Perhitungan TCO (Total Cost Ownership) dan analisis teknis dilakukan pada beberapa alternatif solusi tersebut. Pemilihan solusi terbaik dilakukan dengan Rank Order Centroid Methods (ROC), Rank Reciprocal Methods (RR), Rank Sum Method (RS) dan Equal Weight Methods (EW). Strategi terbaik yang dihasilkan dari analisis dalam penelitian ini adalah "upgrade kapasitas microwave".

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The requirement for data services is currently increasing due to the use of smartphones for social media, online services, and internet access has increased significantly. Mobile Network Operators/MNOs try to balance these needs by increasing the deployment of transmitters/BTS (Base Transceiver Station) that support data services by implementing 4G technology. Following distribution of the BTS locations, it requires transmission between BTS to the core network. Without a transmission network with a sufficiently large capacity, the deployment of 4G BTS will be meaningless.

This paper analyzes the selection of the best strategy that can be applied by Mobile Network Operators in deploying an access transmission network that connects 2G/3G/4G BTS to the core network. In this case the selected area is the Denpasar Bali cluster on the mobile network operator PT.XYZ. At the initial stage, bandwidth requirements are carried out by analyzing data traffic in Denpasar city, Bali, then with trend analysis the estimated bandwidth requirements are determined in the next few years and matched with the BTS configuration preferences at PT. XYZ. Fulfilling bandwidth needs is done by several scenarios. Furthermore, the calculation of TCO (Total Cost Ownership) and technical considerations are carried out on several alternative solution scenarios. Selection of the best scenario is done by the Rank Order Method (ROC), Reciprocal Methods (RR), Rank Sum Method (RS) and Equal Weight Methods (EW). The best scenario resulted from the analysis in this paper is “deployment microwave solution (upgrade capacity) and new optical fiber Hub”

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"Orthogonal Frequency Division Multiplexing (OFDM) adalah suatu teknik pengiriman pembawa jamak yang merupakan bentuk khusus dari Frequency Division Multiplexing (FDM) yang menggunakan spektrum lebih kecil terbagi ke dalam beberapa pembawa dengan mengatur jarak kanal yang lebih kecil sehingga penggunaan bandwidth akan lebih efisien.Pengiriman sinyal OFDM berdasarkan Transformasi Fourier Cepat (TFC-OFDM) memberikan efisiensi bandwidth dan memiliki kemampuan untuk mencegah terjadi interferensi Antar Simbol (IAS) dan Interferensi Antar Pernbawa (IAP) dengan penggunaan cyclic prefix yang dimasukkan di antara simbol-simbol TFD-OFDM, tetapi langkah ini membutuhkan hingga 25% dari bandwidth. Untuk meningkatkan efisiensi bandwidth dan memberikan kemampuan lebih baik dalam mencegah terjadinya IAS dan IAP maka diajukan pengiriman sinyal OFDM berdasarkan Transformasi Wavelet Diskrit (TWD-OFDM).Melalui pemodelan sistem OFDM berdasarkan Transformasi Wavelet Diskrit (TWD) dan Transformasi Fourier Cepat (TFC) pada kanal Additive White Gaussian Noise (AWGN) dan kanal Rayleigh fading lintasan jamak dengan bantuan perangkat lunak MATLAB versi 7.0.1, maka dapat dianalisa sejauh mana Bit Error Rate (BER) pada kedua sistem untuk tingkat Power Noise (Eb/No) yang sama.

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Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier transmission technique, which divides the available frequency into many carriers. OFDM is a special case of Frequency Division Multiplexing (FDM). OFDM uses the much spectrum more efficiently by spacing the channels much more closely together.

Fast Fourier Transform (FFT) based OFDM signal transmission gives bandwidth efficiency and have capability to combat Inter Carrier Interference (IC) and Inter-Symbol Interference (ISI) by adding a cyclic prefix between FFT -OFDM symbols, but this can decrease the bandwidth efficiency roughly 25%. To improve the bandwidth efficiency and ISI, ICI, Discrete Wavelet Transform is proposed.

Through DWT-OFDM and FFT OFDM over Additive White Gaussian Noise (AWGN) and Rayleigh Fading multi path Channel modeling supported with the program-based MATLAB version 7.0.1, we could analyze and compare Bit Error Rate (BER) over the same level of Power Noise (Eb/No)."

"Automotive Transmissions and Transaxles is a comprehensive text that covers the operating principles as well as the service and repair procedures for modern automatic transmissions and transaxles. It is the most complete and up-to-date text on the subject, with hundreds of illustrations and thorough coverage of modern automatic transmissions. The readable format begins with operating theory and progresses from service and maintenance operations to problem diagnosis and repair procedures."

"A design and fabrication of a compact ultra-wideband (UWB) bandpass filter (BPF) using single cell Composite Right-Left Handed Transmission Line (CRLH-TL) is reported in this paper. This compact filter design is achieved using a single cell CRLH-TL structure which is implemented on the FR4 dielectric substrate with permittivitty of 4.4 and dielectric thickness of 1.6mm. The dimensions of the filter structure consider the capability of the fabrication tools in Indonesia. The compact filter operates from 4 GHz to 9.5 GHz with insertion loss less than - 1.5dB."