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Abstrak :
[ABSTRAK
Tumbukan ion berat menghasilkan suatu kondisi dimana jumlah proton dan neutron sama, hal ini disebut symmetric nuclear matter. Pemeriksaan terhadap karakteristik SNM masih dilakukan sampai saat ini. Efek suku non linear dianggap memberikan kontribusi terhadap karakteristik dari SNM, selain itu pemeriksaan terhadap kestabilan persamaan keadaan dilakukan dengan menggunakan metode medan rerata lanjutan. Pengecekkan lanjutan terhadap kestabilan persamaan energi dilakukan dengan mengamati nilai kecepatan suara untuk setiap parameter. Solusi dari persamaan densitas skalar, potensial skalar, dan turunan pertama potensial skalar ditunjukkan oleh titik potong ketiga kurva tersebut. Selain itu, pemeriksaan efek non linear terhadap kenaikan energi ikat dan tekanan setiap kenaikan temperatur juga diperiksa. Parameter G2 yang memiliki konstanta suku cross coupling terbukti memberikan kontribusi menahan laju kenaikan energi pada SNM, hal ini diperlihatkan oleh kurva parameter G2 merupakan kurva paling soft. Kurva parameter NLZ merupakan kurva paling stiff, serta memiliki nilai Cs paling besar saat nilai massa efektif tinggi. Kestabilan persamaan energi untuk setiap parameter masih dinilai realistik, ditinjau dari nilai C2s C2 < 1, namun setiap parameter memiliki daerahketidakstabilan saat massa efektif rendah karena nilai C2s negatif.

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ABSTRACT
Heavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal with the total of the neutron, this condition is named Symmetric Nuclear Matter (SNM). The investigation of SNM characteristic is still being done nowadays. Effects of nonlinear term are considered to contribute to characteristics of SNM, in addition to the examination of the stability equation of state were calculated using extended mean field method. Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter. The solution of scalar density equation, scalar potential, and first derivative of scalar potential are showed by crossing point of three curves. The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature. G2 which has cross coupling term contributes to restrain increasing of SNM energy, it is shown by the G2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when high effective mass condition. The stability of energy equation every parameter could be said mentioned realistic, it is considered from C2 s C2 < 1 value, but each parameter has instability region when low effective mass condition is happened, because the values C2 s are negative. , Heavy ion collision produces a condition where the total of proton equal with the total of the neutron this condition is named Symmetric Nuclear Matter SNM The investigation of SNM characteristic is still being done nowadays Effects of nonlinear term are considered to contribute to characteristics of SNM in addition to the examination of the stability equation of state were calculated using extended mean field method Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter The solution of scalar density equation scalar potential and first derivative of scalar potential are showed by crossing point of three curves The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature G2 which has cross coupling term contributes to restrain increasing of SNM energy it is shown by the G2 parameter curve is softest NLZ is stiffest and has biggest Cs value when high effective mass condition The stability of energy equation every Heavy ion collision produces a condition where the total of proton equal with the total of the neutron, this condition is named Symmetric Nuclear Matter (SNM). The investigation of SNM characteristic is still being done nowadays. Effects of nonlinear term are considered to contribute to characteristics of SNM, in addition to the examination of the stability equation of state were calculated using extended mean field method. Advanced checking the stability of the energy equation is done by observing the sound velocity values each parameter. The solution of scalar density equation, scalar potential, and first derivative of scalar potential are showed by crossing point of three curves. The investigation of non linear effects to the binding energy increasing and pressure every rise of temperature. G2 which has cross coupling term contributes to restrain increasing of SNM energy, it is shown by the G2 parameter curve is softest. NLZ is stiffest, and has biggest Cs value when high effective mass condition. The stability of energy equation every parameter could be said mentioned realistic, it is considered from C2 s C2 < 1 value, but each parameter has instability region when low effective mass condition is happened, because the values C2 s are negative. Key words: coupling, soft, stiff. ix]

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ABSTRAK
kompatibiliser jenis baru berbasis poliuretan telah disintesis dan dikarakterisasi. Poliuretan kompatibiliser ini dipersiapkan melalui reaksi dua tahap, yaitu dengan mereaksikan isosianat metilenabis (sikloheksil isosianat) dan poliol polietilena glikol (PEG) berat molekul 4000 g/mol menghasilkan prepolimer, dilanjutkan dengan pencangkokan lignin. Efek dari komposisi lignin dan perbandingan isosianat : poliol terhadap kemampuan kompatibilitas, analisis termal, dan morfologi diinvestigasi melalui pengujian FT-IR (Fourier Transform Infra-Red Spectroscopy), 1H NMR (Nuclear Magnetic Resonance), STA (Simultaneous Thermal Analysis), serta SEM (Scanning Electron Microscopy). Diketahui poliuretan dengan perbandingan isosianat : poliol 1:2 dan 1:4 menghasilkan poliuretan-lignin cangkok, ditandai dari pengujian FT-IR dan NMR. Sifat kompatibilitas bervariasi, dengan nilai segmen hidrofilik : hidrofobik masing-masing 0,2 dan 0,635. Morfologi cenderung kompatibel, dengan sedikit segregasi fasa hidrofobik dan hidrofilik. Sementara Tg dari tiap produk berada di kisaran 60 oC dengan temperatur dekomposisi di kisaran 430 oC. Hasil yang didapat mengkonfirmasi potensi poliuretan tersebut sebagai agen kompatibiliser pada polyblend

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ABSTRAK
A new family of compatibilizer agent based on polyurethane (PU) were synthesized and characterized. PU have been prepared by two stages reaction. The polymer was prepared by reacting methylenebis cyclohexyl-isocyanate (HMDI) and polyethylene glycol (PEG) with molar mass of 4000 g/mole, then grafting by lignin. The effects of lignin composition and isocyanate/polyol contents on compatible ability, thermal properties, and morphology were investigated by FT-IR (Fourier Transform Infra-Red Spectroscopy), 1H NMR (Nuclear Magnetic Resonance), STA (Simultaneous Thermal Analysis), and SEM (Scanning Electron Microscopy). The results of FT-IR and NMR shown that polyurethane with isocyanate : polyol 1:2 and 1:4 yield polyurethane-grafted-lignin. Variation of compatibility value with ratio of hydrophilic/hydrophobic 0.2 and 0.635 were obtained. The morphology tend to have micro-segregated phase of hydrophilic-hydrophobic content. Meanwhile Tg of each product is on 60 oC with decomposition temperature of 430 oC. The results confirmed the potential of these polyurethanes as a new compatibilizer agent of polymer blends. ;

Abstrak :
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.

Abstrak :
Kopling antara amplifier permukaan miring dan fiber taper lens-ended diselidiki secara teori. Penelitian teori didasarkan pada model gelombang bidang tiga dimensi yang dihitung melalui pergeseran fasa akibat permukaan iring. Kopling diselidiki berkenaan dengan parameter-parameter berkas dari pandu gelombang amplifier lens-ended, dan juga berkenaan dengan posisi fiber. Terjadinya rugi-rugi kopling karena permukaan miring dan karena variasi dari uji lens yang terbaik, rugi untuk permukaan miring 10° ditemukan lebih kecil dari 0.5 dB dibandingkan amplifier permukaan normal.

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The coupling between angled-facet amplifiers and tapered lens-ended fibers is investigated theoretically. The theoretical investigation is based on a three-dimensional plane wave model which accounts for the phase differences introduced by the angled facets. The coupling is investigated with respect to the beam parameters of the amplifier wave guids and the tapered lens-ended fiber, and also with respect to the fiber position. For optimized lens radii the excess loss for 0l0° facet angle is found to be less than 0.5 dB compared to a normal facet amplifier.

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ABSTRAK
Recently, the distributed index microlenses have been introduced as the novel elements for coupling device in microoptic circuitry. A potential advantage of such microlenses as microoptic components is the possibility of gaining a Large nemerical aperture so that incoming Light can be effectively guided, for example in optical coupler, branching circuits, wavelength multiplexer / demultiplexer and so on. The coupling property of microlenses is the basic application of microlenses in optical communication system. this study, a coupling circuit using paired microlenses with distributed index of refraction has been developed. The variation of coupling efficiency due to Lateral offset, angular misalignment and end separation of two coupled microlenses has been experimentally measured. Evaluation on the result was carried out by computer simulation based on phase space representation of ray tracing. It is concluded that the coupling property of distributed index microlenses is affected by the index profile of respective microlenses as predicted by phase space analysis. Furthermore the phase space representation has also been utilized to analyze the coupling efficiency of microoptical coupler.

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ABSTRACT
The aim of this research is to reproduce the experimental result using finite element approach with damage model coupled to creep. The calibration of coupling between creep and local damage model associated with size effect law proposed by Bazant are presented in this thesis. Its behavior was investigated through two kinds of studies, the loading rate effect and residual capacity test. Three different sizes of beam, which are geometrically similar specimens, were simulated in three point bending test and creep test divided into load level test and residual capacity test. Numerical simulation was doneusing existing finite element code Aster_ Code developed by EDF (Eiectricite de France) for coupling between local damage based on bi-linear elasto-damage model and creep based on Benboudjema theory. Result show that the finite element code is capable to reproduce the experimental result qualitatively. The interaction between creep and local damage is shown through size effect plot by giving the behavior shift to the right, which means that the materials become more brittle when creep appears.

Abstrak :
Refactoring merupakan teknik pemograman yang bertujuan untuk meningkatkan kualitas kode program. Sebuah studi menunjukkan bahwa tujuh puluh delapan persen (78 %) dari 328 insinyur perangkat lunak setuju bahwa refactoring memberikan dampak positif pada pekerjaan mereka. Sebanyak 43,3 % responden menyatakan refactoring dapat meningkat keterbacaan (readability) kode dan 29,9 % nya menyatakan refactoring meningkatkan maintainability kode. Penelitian ini bertujuan untuk menguji dampak refactoring terhadap Dispersion Coupling Harmfulness kode sumber. Pemilihan smell kopling tersebar (dispersion coupling) didasarkan pada kerawanannya untuk diubah (change-proneness), banyak ditemukan (numerosity) pada kode program dan dampaknya terhadap kualitas perangkat lunak. Penelitian ini dilakukan dengan cara eksperimen yang terdiri dari serangkaian pengujian. Setiap pengujian terdiri dari tindakan refactoring tertentu, terhadap kode program sebagai objek dan pemrogram sebagai subjek nya. Berdasarkan data yang dikumpulkan dari eksperimen, analisis statistik dilakukan untuk mengetahui dampak refactoring terhadap dispersion coupling harmfulness kode program. Hasil eksperimen menunjukkan 78% sampel mengalami penurunan Dispersion Coupling Harmfulness hingga mencapai nilai 0. Hal ini menunjukkan manfaat dari refactoring terhadap pengendalian kopling tersebar yang kemudian berdampak pada peningkatan kualitas kode sumber. ......Refactoring is a programming technique that aims to improve the quality of program code. One study showed that seventy-eight percent (78%) of 328 software engineers agreed that refactoring had a positive impact on their work. As many as 43.3% of respondents stated that refactoring can increase code readability and 29.9% stated that refactoring increases code maintainability. This study aims to examine the impact of refactoring on dispersion coupling harmfulness of source code. The choice of dispersion coupling smells is based on their change-proneness, numerosity in program code and their impact on software quality. This research was conducted by means of an experiment consisting of a series of tests. Each test consists of a specific refactoring action, to the program code as object and the programmer as its subject. Based on data collected from experiments, statistical analysis was carried out to determine the impact of refactoring on source code. The experimental results showed that the value of Dispersion Coupling Harmfulness from 78% of the samples became 0 after refactoring. This demonstrates the benefits of refactoring against dispersed coupling control which in turn has an impact on improving the quality of the source code.

Abstrak :
Polypropylene diperkuat serat flax dipersiapkan untuk mengetahui pengaruh penambahan serat dan coupling agent terhadap sifat - sifat mekanik dari komposit. Komposit flax/polypropylene dibuat dengan kandungan yang berbeda (10,20 dan 30 % berat). Sedangkan untuk coupling agent dengan tipe maleic anhydride polypropylene dilakukan penambahan 4% pada masing - masing komposisi komposit. Proses pembuatan material dilakukan dengan cara ekstrusi dan injeksi. Sifat - sifat mekanik yang diteliti yaitu tarik, tekan, tekuk, puntir dan impak. Modulus dan tegangan maksimum dari flax/polypropylene meningkat dengan penambahan serat. Pengaruh yang sama juga dihasilkan melalui penambahan coupling agent. ......Flax fibre reinforced polypropylene were prepared to investigate the influence of fibre loading and coupling agent on the mechanical properties of the composite. Flax/polypropylene composite was made with different content (10, 20 and 30 wt %). Whereas, coupling agent of maleic anhydride polypropylene was added by 4% to each composite composition. The process making of materials was performed by extrusion and injection. The mechanical properties of composite such as tensile, compression, flexural, torsion and impact were investigated. Modulus and maximum stress of flax/polypropylene increased with increase of fibres loading. The same effect was also generated through the addition of coupling agent.