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Abstrak :
Teknik pengkodean suara digunakan dalam teknologi telekomunikasi untuk memanfaatkan informasi yang besar sehingga dapat meningkatkan efisiensi penggunaan kapasitas saluran. Akan tetapi pada teknik pengkodean suara masih dihadapkan kepada dilema antara besarnya laju bit yang dihasilkan dengan tingkat kualitas suara yang dihasilkan sebagai kompensasi dari penekanan laju bit ini. Mixed Excitation Linear Prediction (MELP) merupakan suatu metode pengkodean suara yang dikembangkan berdasarkan metode Linear Predictive Coding (LPC), yang menggunakan S4 bit untuk setiap frame suara selama 22,5 ms sehingga dihasilkan laju bit sebesar 2,4 kbps. Metode MELP ini memperbaiki kualitas sintesa ucapan hasil pengkodean dengan penambahan empat parameter baru, yaitu: pencampuran eksilasi pulsa dan derau, pulsa-pulsa aperiodik, filter Adaptive Spectral Enhancement, dan filter Pulse Dispersion. Pada skripsi ini dianalisis unjuk kerja dari metode MELP dilihat dari kualitas suara sintesis yang dihasilkan ditinjau dari segi SNRR, perbandingan spektral, dan penilaian subyektif oleh 40 orang pendengar. Hasil yang didapat menunjukkan bahwa suara sintesis hasil kompresi MELP masih dapat jelas diterima oleh telinga manusia dalam arti bahwa informasi masih dapat diterima dengan baik dengan kualitas suara yang cukup baik.

Abstrak :
In electric power systems that consist of some generators, electric power stability in supplies side becomes the most important problems, which must be paid attention. In the interconnection system, if there are some troubles in transmission, generator or load will cause another generators feel the existence of instability condition. For instability condition which not too serious, system can overcome the fault and will not influence stability of system as a whole. However, for in big scale of fault and happened in a long duration can be ejected system becoming unstable and will result hampered of electrics energy supply to the load For the worst condition could be blackout condition. This article studies about improvement of the stability of the system by using excitation current and the prime mover of generators, which is coordinated fuzzy logic control in synchronize generator. By using annexation from three methods above, the condition of stability of the power system can attain the stability. The transient stability needed control in order that system with good stability can return to normal condition. Faulted electric power system often caused by failure in controlling the transient stability. It is because in transient stability forms critical condition for electrical power system. By controlling the level of excitation current and mechanical energy from the prime mover of generators which controlled by fuzzy logic when the fault is happened will make acceleration area become decreasing and deceleration area become increasing with the result that system can be stable quickly. It visible that from result of simulation obtained if using generator oscillation of fuzzy logic control, transient period becoming shorter and amplitude of oscillation wave is smaller compare by using without fuzzy logic. Likewise, this method is able loo to overcome transient condition at starting period of a generator.

Abstrak :
Sistem tenaga listrik modem menggunakan pengatur tegangan dan sistem penguatan medan, untuk menjaga kestabilan sistem terhadap ganggguan. Pada suatu sistem penguatan medan dapat ditambahkan Pembatas Eksitasi Kurang (Under Excitation Limiter). Fungsi Pembatas Eksitasi Kurang (PEK) adalah menjaga kestabilan generator terhadap panas pada inti jangkar, mencegah kehilangan eksitasi oleh gangguan yang cukup ekstrim. PEK bekerja berdasarkan galat pengatur tegangan dan tegangan acuan. Setelah diolah PEK, sinyal ini diteruskan ke medan generator untuk mengembalikan tegangan medan pada nilai yang diinginkan. Simulasi dalam tesis ini memerlukan kurva kemampulan generator. Generator diberi nilai daya yang berada di luar kurva, yang memisalkan keadaan tidak stabil. Hasil simulasi menunjukkan bahwa tegangan terminal dikembalikan kepada nilai keadaan stabil. Tanggapan tegangan medan mirip dengan tanggapan fungsi orde satu dengan masukan fungsi undak. Parameter PEK harus disesuaikan dengan batas kestabilan generator. Batas kerja PEK didasarkan pada kurva kemampuan generator. Simulasi meninjau sistem satu pembangkit dengan daya 2 KW dan satu bus tak terhingga (infinite bus). Namun hasilnya dapat diterapkan pada sistem dengan daya lebih besar. Untuk pengembangan studi tentang PEK, dapat diteliti penggunaannya bersama Pembatas Eksitasi Lebih (Over Excitation Limiter), dan pada sistem dengan banyak bus tak terhingga. ...... Modem power systems apply voltage controller and excitation systems to keep their stability against disturbance. To the excitation system can be added an under excitation limiter (UEL}. UEL functions to keep generator's stability against armature core overheating, and loss of excitation due to relatively big disturbances. UEL operates by using the error between controller's output and reference voltage. After being processed by the UEL, the signal is passed to the generator's field to return the field voltage to its desired value. Simulation in this thesis needs generator capability curve. The generator was given a power value outside the curve. The value reflected an instable condition. The results of the simulation showed that terminal voltage was brought back to a value in the stable region. The field voltage response is similar to a first order response with step function input. UEL parameters should be adjusted to the generator's stability limits. UEL's limit is based on generator capability curve. The simulation observed a 2 KW generator system connected to an infinite bus. However the results can be applicable to bigger systems. Continuing the study on UEL, further UEL experiments together with over excitation limiters (OEL), and its use on an many infinite buses can be conducted.

Abstrak :
Nanopartikel emas (AuNPs) merupakan suatu bahan yang mulai marak digunakan dalam bioimaging. AuNPs yang digunakan dalam bioimaging umumnya disintesis menggunakan metode kimiawi. Salah satu teknik pencitraan yang memakai AuNPs sebagai medium adalah Two photon microscopy. Teknik ini memanfaatkan eksitasi two photon pada AuNPs untuk memberikan label pada sampel-sampel biologis. Pada penelitian ini, telah disintesis AuNPs menggunakan metode ablasi laser menggunakan laser Nd:YAG dengan panjang gelombang 1064 nm selama 5 menit. Tiga jenis pelarut (aqueous, polyvinyl alcohol dan polyethylene glycol) digunakan untuk memodifikasi diameter AuNPs. Masing-masing AuNPs ini menunjukkan puncak absorbsi yang berbeda pada spektrometri UV-Vis. Spektrum ini kemudian dibandingkan dengan sebuah alat simulasi pada MATLAB. Didapatkan besar diameter AuNPs untuk masing-masing parameter adalah 16,2 nm, 16,7 nm, dan 15,9 nm secara berurutan. Telah dibuat pula setup optik untuk melakukan uji eksitasi two photon (TPE) pada AuNPs memvariasikan daya dari laser femtosecond. Didapatkan bahwa TPE terjadi pada rentang panjang gelombang ~490 sampai ~500 nm dengan daya laser sebear 1,2 W sampai 1,8 W. ......Gold nanoparticles (AuNPs) is a material that has been gaining attraction in bioimaging. AuNPs that used in bioimaging usually shynthetized using chemmicals method. An example of imaging techniques that use AuNPs as medium is Two photon microscopy. This technique use two photon excitation on AuNPs to dye or labels biological samples. Ini this experiment, AuNPs have been successfully fabricated using laser ablation method by Nd:YAG lser with 1064 nm wavelength for 5 minute. Three different solution (aqueous, polyvinyl alcohol and polyethylene glycol) was applied to modify AuNPs diameter. Each of these AuNPs was observed by mean UV-Vis spectroscopy exhibit different absorption peak. This spectrum then was compared to simulation tool on MATLAB. The measured AuNPs’ diameters was 16,2 nm, 16,7 nm, dan 15,9 nm repectively. An optical setup for two photon excitation (TPE) experiment on AuNPs has also been made by varying the power of femtosecond laser. TPE was detected at ~490 to ~500 nm range with laser power about 1,2 W to 1,8 W.

Abstrak :
Skripsi ini membahas mengenai pemodelan dan simulasi rangkaian enkoder pada teknik pengkodean suara VSELP. VSELP merupakan suatu teknik pengkodean suara atau kompresi pada komunikasi selular yang memberikan tingkat kompresi sebesar delapan kilo bit persekon. Bagian Enkoder VSELP melakukan kompresi dengan metode Linear Prediction Coding dan memodelkan nilai eksitasi dengan kode buku adaptif dan kode buku eksitasi.Bagian Enkoder ini akan disimulasikan dan dibuktikan tingkat kompresi suaranya. Simulasi dilakukan dengan secara offline yang berarti suara direkam terlebih dahulu dan kemudian diproses secara terpisah. Simulasi tersebut akan menghasilkan sebuah bentuk dokumen dari data asli yang akan memberikan tingkat kompresi sebesar delapan kilo bit perdetik.

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This final project discusses designing and simulating encoder part of VSELP sound compression. Vector Sum Excitation Linear Prediction is one of the technique of sound compression or sound coding on cellular communication that give compression into eight kilo bit per second. VSELP Encoder compressed sound data with linear prediction coding and model the excitation with adaptive codebook and excitation codebook This Encoder part will be simulated to prove the compression level of it. Simulation done in offline condition whereas the data recorded and processed separately. Simulation will give a new file from the origin data that give the eight kilo bit persecond compression.

Abstrak :
The work presented in this thesis is divided two subjects. First, devoted to the behavior, mechanic model, simulation and analysis of plate tectonics under excitation force approximated. Approach of an Earthquake are assumptions on the nature of the rupture process, review the evidence for the essential importance of the flow under plate with the modes of deformations. Earthquake is primarily a mechanical process which appears as genuire rupture of crust and the earth behaves as an elastic body during the short time span of the phenomena. The friction has probably a fundamental role in the mechanics of the earthquakes. Rock mechanicians consider an earthquake as a stick-slip event controlled by the friction properties of the fault. During an earthquake, on the nature of the fault and on the effect of trapped fluids within the crust at seismogenic depth, fault zone head seismic waves are generated by a shear-dislocation source and then propagated through the modeled earth medium. Wave propagation theory is used to solve the problem at hand for wave motion response, which is found as the superposition of the mean and scattered wave response. Second, devoted model of the wave propagation, an important modeling tool of fault zone properties at depth can be provided by accurate simulations of seismic fault zone head and trapped waves for realistic structures. Analytical solutions for seismic wave fields generated by double-couple sources at material discontinuities in plane-parallel structures. Extensive 2D studies of the dependency of fault zone wave motion on basic media properties and source receiver geometries show that there are significant trade offs between propagation distances along the structure, fault zone width, impedance contrasts, source location within. And the most important applications of the theory of structural dynamics is in analyzing the response of the structures to ground shaking caused by an earthquake. The study for earthquake response of linear SDF systems to earthquake motions concerned the displacement, velocity and acceleration. Then we introduced the response spectrum concept, which is central to earthquake engineering, together with procedures to determine the peak response of systems directly from the response spectrum.

Abstrak :
Tujuan dari penulisan skripsi ini adalah untuk menganalisis respons dari struktur portal tiga dimensi (3D) yang memiliki peredam geser akibat dari eksitasi seismik. Respons yang dimaksud adalah respons kinematik yaitu lendutan, kecepatan dan percepatan serta respons mekanik berupa gaya dalam dan reaksi perletakan dari struktur yang ditinjau. Struktur portal tiga dimensi dimodelkan sebagai struktur portal lima lantai untuk bangunan perbankan dengan vaultroom sebagai ruang penyimpanan. Vaultroom dibentuk dari tembok beton dengan ketebalan mininum 30 cm, sehingga memiliki kekakuan yang sangat besar dibandingkan dengan kekakuan bangunan. Penempatan vaultroom pada bagian tertentu dari struktur akan mengakibatkan eksentrisitas pusat massa dan pusat rotasi struktur sehingga menimbulkan efek torsi pada saat pembebanan dinamik. Peredam geser akan diletakan di antara vaultroom dan pelat vaultroom. Peredam geser yang digunakan diharapkan dapat menreduksi respons dari struktur akibat kekakuan eksentris struktur saat gempa.

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The aim of this research is to analyze the responses of eccentric structure with friction damper. The responses are kinematic and mechanic responses of the structure. The kinematic and mechanic responses consist of deflection, velocity, acceleration, element force, and base reaction. The three dimensional frame is modeled as a five-story building for a bank with vault. The room is made from 30 cm-thick mass concrete as a wall. Vaultroom will stiffen some part of structure. Eccentricity of center of mass and center of rotation will then occur. This will emerge torsion effect when dynamic excitation is applied to the building. Friction damper will placed between vaultroom and vaultroom plate. Seismic responses of structure are expected to be reduced by using this friction damper.

Abstrak :
Myofascial Pain Syndrome (MPS) adalah salah satu keluhan muskuloskeletal terbanyak dalam pelayanan kesehatan. MPS diduga dapat menyebabkan gangguan pada koordinasi otot-otot skapula. Penelitian ini bertujuan untuk membuktikan adanya hubungan terhadap kejadian MPS upper trapezius dengan ketidakseimbangan eksitasi otot upper trapezius, otot lower trapezius dan serratus anterior. Penelitian ini adalah studi potong lintang observasional. Sebanyak 34 subjek penelitian yang terdiri dari 17 subjek dengan MPS kronis dan 17 subjek non-MPS berusia 18-59 tahun dikumpulkan. Pengambilan data dilakukan menggunakan alat EMG permukaan Neurotrac MyoplusPro 4. Pengukuran eksitasi otot dilakukan pada otot upper trapezius, lower trapezius, dan serratus anterior. Pengukuran tersebut dilakukan pada saat bahu abduksi 0-180° tanpa beban, 25% beban maksimal, dan 50% beban maksimal. Pengukuran dilakukan tiga kali dan diambil reratanya. Rerata eksitasi diambil rasio perbandingan antara ketiga otot tersebut dan dibandingkan antara populasi MPS dengan populasi non-MPS. Uji statistik yang digunakan adalah uji T tidak berpasangan jika data pada sebaran normal. Jika sebaran tidak normal maka digunakan Mann-Whitney test. Hasil penelitian ini menemukan bahwa terdapat perbedaan rasio eksitasi yang bermakna pada otot upper trapezius dengan lower trapezius pada penderita MPS kronis dibandingkan dengan non-MPS pada ketiga tingkatan beban yang dilakukan, ditemukan perbandingan antara kedua kelompok tersebut dengan rata-rata perbedaan 2:1. Sedangkan, tidak terdapat perbedaan bermakna dari rasio otot upper trapezius dengan serratus anterior, dan lower trapezius dengan serratus anterior antara kedua populasi tersebut. ......Myofascial Pain Syndrome (MPS) is one of the most common musculoskeletal complaints in health services. MPS is suggested to cause a discoordination of the scapula muscles. This study aims to prove that there is a relationship between the incidence of upper trapezius MPS and the imbalance of excitation of the upper trapezius, lower trapezius and serratus anterior muscles. This study was an observational cross-sectional study. A total of 34 study subjects consisting of 17 subjects with chronic MPS and 17 non-MPS subjects aged 18-59 years were collected. Data were collected using the Neurotrac MyoplusPro 4 surface EMG device. Muscle excitation was measured on the upper trapezius, lower trapezius, and serratus anterior muscles. These measurements were carried out when the shoulder was abducted 0-180° with no load, 25% of the maximum load, and 50% of the maximum load. Measurements were made three times and the average was taken. The average excitation ratio was taken between the three muscles and compared between the MPS population and the non-MPS population. The statistical test used was the unpaired T test if the data were in a normal distribution. If the distribution is not normal, then the Mann-Whitney test is used. The results of this study found that there was a significant difference in the excitation ratio of the upper trapezius and lower trapezius muscles in patients with chronic MPS compared to non-MPS at the three levels of load carried out, a comparison between the two groups was found with an average ratio of 2:1. Meanwhile, there was no significant difference in the ratio of the upper trapezius muscle to the serratus anterior, and the lower trapezius to the serratus anterior between the two populations.

Abstrak :
This book discusses the problem of electromagnetic wave excitation in spatial regions with spherical boundaries and the accurate mathematical modeling based on numerical and analytical methods to significantly reduce the time required for developing new antenna devices. It particularly focuses on elements and systems on mobile objects of complex shape that are made of new technological materials. The experimental development of such devices and systems is an extremely time-consuming, lengthy, and expensive process. The book is intended for senior and postgraduate students and researchers working in the fields of radiophysics, radio engineering and antenna design. The authors assume that readers understand the basics of vector and tensor analysis, as well as the general theory of electrodynamics. The original results presented can be directly used in the development of spherical antennas and antenna systems for the mobile objects.

Abstrak :
Isolated atoms in group II-B such as zinc (Zn), cadmium (Cd), and mercury (Hg) are chemically stable. These atoms are important in the formation of excimer. Zinc in particular has been investigated by many researchers, as Zn2 excimer holds promise because of its long lifetime and its potential as an energy-storage system. However, excimer’s benefits are based on excitation of the outermost electron. Our study confirmed the quantum dynamical condensation processes in which inner-core excitation arises due to ion-recombination between the vapor phase and the solid phase. The X-ray diffraction of the condensed structure of zinc film had included strong diffuse scattering depending on the incident energies. In this research, we produced the excited state of zinc excimer characterized by an extremely long lifetime. Intriguingly, a feature of the zinc film is that it transforms from metallic to insulative. It is thought that such a structure with this characteristic has been affected by electron spin and atomic distortion by inner-core excitation. The structure obtained in our experiment is expected to prove promising in engineering applications, such as electronics, spintronics, and batteries.