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"Dermaga merupakan salah satu komponen yang penting dalam kegiatan perekonomian suatu daerah, dan dapat mengakibatkan kerugian yang besar secara ekonomis jika mengalami kerusakan. Salah satu tipe dermaga yang banyak ditemui di Indonesia adalah dermaga tipe pile supported wharf, yaitu dermaga yang di dukung oleh tiang pancang. Salah satu alternatif desain dermaga yang sedang berkembang adalah dengan mempergunakan sistem sesimic isolation, yang diharapkan mampu memberikan performa yang lebih baik dari dermaga konvensional. Penelitian ini bertujuan antara lain mempelajari performa dermaga seismic isolation terhadap gaya statik dan dinamiknya, mengetahui korelasi antara dimensi dermaga, bentuk dermaga (irregular/ regular), dan seberapa besar penggunaan seismic isolation dapat menghemat material tiang pancang. Metode penelitian yang dipergunakan berupa analisa model Finite Element 3 dimensi, dimana untuk sistem seismic isolation dipergunakan tipe LRB (Lead Rubber Bearing). Model yang dipergunakan dalam penelitian ini dibagi menjadi 2 macam, yaitu model konvensional dan seismic isolation, dimana masing-masing divariasikan menjadi bentuk reguler dan irregular, kemudian divariasikan terhadap rasio Panjang/lebar, dengan total 18 variasi model. Dimana dari hasil penelitian didapatkan bahwa penggunaan sistem seismic isolation mampu menghemat material tiang pancang sebesar 21% dan efektif pada dermaga dengan rasio panjang/lebar yang tinggi maupun dengan bentuk irregular.

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Wharf structure is an important element in the economic activity of a society, it could cause a huge economic loss when its damaged and cannot be operated. Pile supported wharf is one of wharf variant that often found in Indonesia, this wharf is a deck (usually from concrete) supported by several piles. One of the alternative designs that has been emerging is the seismic isolation system, which expected to perform and give better results compared to the conventional wharf design. The objectives of this research are to study the seismic isolated wharf performance with its dynamic and static force, to study the correlation between the dimension/configuration and seismic isolation usage, and to study how much savings can be done (in terms of pile material) with seismic isolation system.

The research method used is a 3D finite element modeling, which uses LRB (Lead Rubber Bearing) type isolator as the seismic isolation mechanism. The models are classified into 2 groups, seismic isolated and conventional. Each group are varied into regular and irregular configuration, and also varied with the dimension ratio, with total 18 variation models. From this research, it is shown that the usage seismic isolation system can be used to save 21 % pile material, and that seismic isolation system gives a better result when applied on wharf that has high length/width dimension and/or irregular configuration."

"Hard water causes the CaCO3 scale formation on the pipe walls and heat exchanger equipments in industrial or domestic water processes. A great number of experimental researches on the prevention of the CaCO3 precipitation process by magnetic field have been carried out. In this research, Na2CO3 and CaCl2 solutions was magnetized in the circulated flow condition (dynamic fluid system). The velocity of fluid and the circulation time was modified to examine its influences to the magnetization process. CaCO3 content was measured by titration method of EDTA complexometry. Conductivity test was conducted to find out hydrate ion bonding.

The results showed that magnetization increased the CaCO3 formation and the optimum process reaches for 10 minutes circulation on 0.554 m/s of flow rate. Magnetic field decreases the conductivities of Na2CO3 and CaCl2 solution, hence reduced the ion hydrate bonding. These results showed that magnetization on Na2CO3 and CaCl2 ionic solution was effective in controlling the CaCO3 formation by increasing CaCO3 precipitation."

"Persamaan model Dubinin-Astakhov digunakan untuk mencari pengaruh karakteristik karbon aktif yang digunakan sebagai adsorben terhadap unjuk kerja pada proses adsorpsi dan proses desorpsi dari sistem ANG (Adsorbed Natural Gas) dalam keadaan dinamis. Keadaan dinamis adalah keadaan kerja sebenarnya dimana pada tahapan adsorpsi terjadi kenaikan temperatur dan pada tahapan desorpsi terjadi penurunan temperatur. Dari hasil pendekatan teoritis menggunakan persamaan Dubinin-Astakhov akan didapatkan karakteristik karbon aktif optimal yang menghasilkan unjuk kerja paling maksimal terhadap perubahan temperatur yang terjadi (ΔT). Untuk mendapatkan kapasitas adsorpsi dan desorpsi yang baik dalam keadaan dinamis maka dibutuhkan karbon aktif yang memiliki volume mikropori (Wo) dan nilai penyebaran pori (n) yang besar. Sedangkan lebar pori (Lo) yang akan menghasilkan kapasitas tersimpan (Qds) terbaik adalah lebar pori (Lo) dengan nilai 1,5 nm dan untuk menghasilkan kapasitas terkirim (Qdd) terbaik adalah lebar pori (Lo) dengan nilai 2,3 nm.

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Dubinin-Astakhov equation is use to find the influence from the characteristics of activated carbon that is use as adsorbent to the performance on adsorption process and desorption process under dynamic condition. Dynamic condition is the real work condition where in that condition an adsorption process there is an increase in temperature and a desorption process there is an decrease in temperature. From the theoritical study using Dubinin-Astakhov equation we can get the optimal characteristics of activated carbon that produce the greater performance do to the temperatur change that happen (ΔT). To get the greater adsorption dan desorption capacity under dynamic condition we must use activated carbon that have bigger mikropore volume (Wo) and pore size distribution (n). For the micropore width (Lo) that can produce the greater stored capacity is the micropore width (Lo) with the value around 1,5 nm and greater delivered capacity is the micropore width (Lo) with the value around 2,3 nm."

"This book treats dynamic stability of structures under nonconservative forces. It is not a mathematics-based, but rather a dynamics-phenomena-oriented monograph, written with a full experimental background. Starting with fundamentals on stability of columns under nonconservative forces, it then deals with the divergence of Eulers column under a dead (conservative) loading from a view point of dynamic stability. Three experiments with cantilevered columns under a rocket-based follower force are described to present the verifiability of nonconservative problems of structural stability. Dynamic stability of columns under pulsating forces is discussed through analog experiments, and by analytical and experimental procedures together with related theories. Throughout the volume the authors retain a good balance between theory and experiments on dynamic stability of columns under nonconservative loading, offering a new window to dynamic stability of structures, promoting student- and scientist-friendly experiments."