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"Micromechanics of composites : multipole expansion approach is the first book to introduce micromechanics researchers to a more efficient and accurate alternative to computational micromechanics, which requires heavy computational effort and the need to extract meaningful data from a multitude of numbers produced by finite element software code. In this book Dr. Kushch demonstrates the development of the multipole expansion method, including recent new results in the theory of special functions and rigorous convergence proof of the obtained series solutions. The complete analytical solutions and accurate numerical data contained in the book have been obtained in a unified manner for a number of the multiple inclusion models of finite, semi, and infinite heterogeneous solids. Contemporary topics of micromechanics covered in the book include composites with imperfect and partially debonded interface, nanocomposites, cracked solids, statistics of the local fields, and brittle strength of disordered composites."

"ABSTRAKPenghubung geser spiral adalah salah satu jenis penghubung geser yang digunakan pada struktur komposit. Pengujian terhadap besarnya kekuatan penghubung geser spiral dilakukan dengan pengujian push out. Dari pengujian tersebut diperoleh grafik hubungan beban-slip yang kemudian dipergunakan sebagai input karakteristik link.. Link adalah elemen konektor dalam SAP2000 yang dipergunakan sebagai konektor pada balok komposit baja-beton.Permodelan dilakukan pada 4 spesimen yang memiliki properti material dan karakteristik link yang berbeda satu sama lain. Hasil menunjukkan bahwa link pada program SAP2000 mampu mengidealisasikan perilaku dari penghubung geser spiral dengan kontrol validasi berupa lendutan hasil pengujian eksperimental yang dilakukan oleh Council of Scientific and Industrial Research Govt. of India New Delhi (1969).

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ABSTRACTSpiral shear connector is one of shear connector types used in composite structure. Shear connector capacity tests could be done by push out test. Those test results is a load-slip relationship curve that will be used as an input for link characteristic. Link is a connector element in SAP2000 used as a connector for steel-concrete composite beam.Modelling of steel-concrete composite beam will be done for 4 specimens which has different material properties and link characteristics one anothers. Results show that link connector in SAP2000 could idealize the behaviour of spiral shear connector with validation control model using deflection from experimental test by Council of Scientific and Industrial Research Govt. of India New Delhi (1969)."

"Komposit Al/SiCp coating telah dihasilkan dari gravity casting. Dengan partikel SiC dilapisi oleh lapisan metal oksida yang diperoleh dari proses electroless plating dalam larutan elektrolit HNO3, dengan konsentrasi magnesium (Mg) dalam larutan elektrolit tersebut bervariasi dari 0,002 sampai 0,012 mol dan konsentrasi aluminum (Al) dibuat tetap 0,018 mol. Partikel SiC coating tersebut, digunakan untuk membuat komposit (MMCs) dengan persen volume SiC bervariasi dari 2 sampai 20,5 vol%. Komposit aluminum yang dihasilkan, dianalisis dalam metalografi dan sifat mekanik. Dari komposit tersebut, diperoleh bahwa sifat mekanik komposit dapat meningkat dibandingkan dengan matriks aluminum, seperti kekerasan meningkat dari 76,23 BHN menjadi 96,82 BHN, porositas turun dari 8,97% menjadi 3,81% dan laju keausan turun dari 10,6 x 10-6/mm/mm3 menjadi 2,63 x 10-6/mm/mm3 karena penambahan persen volume SiC 15%. Sedangkan kuat tarik komposit Al/SiCp turun dibandingkan dengan matriks aluminumnya dari 203,31 Mpa menjadi 191,49 Mpa. Pembentukan fasa spinel MgAl2O4 di interface Al/SiC rendah, karena magnesium berinteraksi dengan silikon, membentuk fasa baru Mg2Si yang teridentifikasi oleh XRD pada semua komposisi persen volume SiC coating. Pembentukan fasa Mg2Si pada matriks aluminum, dapat meningkatkan sifat mekanis komposit Al/SiCp.

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Al/SiCp coating MMCs has been produced by gravity casting. The SiC particles were coated with metal oxide film obtained by electroless plating in liquid electrolyte HNO3, and liquid electrolyte made various magnesium (Mg) concentrations from 0.002 to 0.012 mole and a concentration aluminum (Al) have made constant is 0,018 mole. The SiCp coated, used for making MMCs was various volume percent SiCp from 2 to 20.5 vol%. The aluminum composites produced was analysed both metalography and mechanical properties. It is obtained that mechanical properties of these composites are increased compared to unreinforced, i.e hardness increased from 76.23 BHN to 96.82 BHN, porosity decreased from 8.97% to 3.81% and wear rates decreased from 10.6 x 10-6/mm/mm3 to 2.63 x 10-6/mm/mm3 due to the additions volume percent SiC up to 15%. In contrast, the tensile strength of Al/SiCp composites decreased from 203.31 MPa to 191.49 MPa. Spinel phase of MgAl2O4 at the interface Al/SiC is low, due to magnesium interact with silicon, formed a new phase of Mg2Si indentified by XRD in all composition of volume percent SiC coating. A new phase of Mg2Si formed in the matrix aluminum, increased mechanical properties of Al/SiCp composites."

"Komposit Al/SiCp coating telah dihasilkan dari gravity casting. Dengan partikel SiC dilapisi oleh lapisan metal oksida yang diperoleh dari proses electroless plating dalam larutan elektrolit HNO3, dengan konsentrasi magnesium (Mg) dalam larutan elektrolit tersebut bervariasi dari 0,002 sampai 0,012 mol dan konsentrasi aluminum (Al) dibuat tetap 0,018 mol. Partikel SiC coating tersebut, digunakan untuk membuat komposit (MMCs) dengan persen volume SiC bervariasi dari 2 sampai 20,5 vol%. Komposit aluminum yang dihasilkan, dianalisis dalam metalografi dan sifat mekanik. Dari komposit tersebut, diperoleh bahwa sifat mekanik komposit dapat meningkat dibandingkan dengan matriks aluminum, seperti kekerasan meningkat dari 76,23 BHN menjadi 96,82 BHN, porositas turun dari 8,97% menjadi 3,81% dan laju keausan turun dari 10,6 x 10-6/mm/mm3 menjadi 2,63 x 10-6/mm/mm3 karena penambahan persen volume SiC 15%. Sedangkan kuat tarik komposit Al/SiCp turun dibandingkan dengan matriks aluminumnya dari 203,31 Mpa menjadi 191,49 Mpa. Pembentukan fasa spinel MgAl2O4 di interface Al/SiC rendah, karena magnesium berinteraksi dengan silikon, membentuk fasa baru Mg2Si yang teridentifikasi oleh XRD pada semua komposisi persen volume SiC coating. Pembentukan fasa Mg2Si pada matriks aluminum, dapat meningkatkan sifat mekanis komposit Al/SiCp.

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Al/SiCp coating MMCs has been produced by gravity casting. The SiC particles were coated with metal oxide film obtained by electroless plating in liquid electrolyte HNO3, and liquid electrolyte made various magnesium (Mg) concentrations from 0.002 to 0.012 mole and a concentration aluminum (Al) have made constant is 0,018 mole. The SiCp coated, used for making MMCs was various volume percent SiCp from 2 to 20.5 vol%. The aluminum composites produced was analysed both metalography and mechanical properties. It is obtained that mechanical properties of these composites are increased compared to unreinforced, i.e hardness increased from 76.23 BHN to 96.82 BHN, porosity decreased from 8.97% to 3.81% and wear rates decreased from 10.6 x 10-6/mm/mm3 to 2.63 x 10-6/mm/mm3 due to the additions volume percent SiC up to 15%. In contrast, the tensile strength of Al/SiCp composites decreased from 203.31 MPa to 191.49 MPa. Spinel phase of MgAl2O4 at the interface Al/SiC is low, due to magnesium interact with silicon, formed a new phase of Mg2Si indentified by XRD in all composition of volume percent SiC coating. A new phase of Mg2Si formed in the matrix aluminum, increased mechanical properties of Al/SiCp composites."

"Komposit Matriks Logam (KML), pada saat ini merupakan salah satu material yang banyak digunakan di industri manufaktur terutama yang berbasis alumunium, karena alumunium ini mempunyai berat jenis yang rendah. Material alumunium sebagai matriks dengan penguat Al2O3 maupun SiC sudah banyak digunakan dalam pembuatan KML. Proses pembuatan KML di Indonesia merupakan hal yang baru-baru ini ramai diminati, meskipun penelitian awal sudah dilakukan jauh sebelumnya. Faktor penting pada pembuatan KML adalah menghidari adanya keropos atau adanya porositas pada hasil produk. Karena itu pada percobaan ini setelah dilakukan proses pengadukan dilanjutkan dengan proses tempa untuk mengurangi adanya porositas tersebut. Bahan yang digunakan sebagai matriks adalah Al-5%Cu dengan kandungan 4% Mg sebagai wetting agent, sedangkan penguat yang digunakan adalah 5 dan 10% Vf Al2O3 serta 5 dan 10% Vf SiC. Pengujian mekanik yang dilakukan antara lain uji tarik, kekerasan dan keausan, sedangkan pengujian fisik; metalografi, berat jenis, porositas, SEM/EDS dan XRD, untuk melihat fasa dan senyawa baru. Dengan pertambahan penguat Al2O3 maupun SiC terjadi kenaikkan sifat mekanik antaralain naiknya angka kekerasan dan turunnya nilai keausan.

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The Metal Matrix Composite (MMCs), one of a kind material which is widely used in manufacturing industry, especially made form aluminum. It is caused by the easiness to process and the weight that is lighter then the other metals. The using of reinforced material such as Al2O3 and SiC have been known to make MMCs. The making of MMCs in Indonesia have just developed recently, eventough the previous research have been conducted for a long time. The important factor in making MMCs in to prevent the porosity at it's product. This is the reason why we conduct a forging process after the agitation process.

The materials used as matrix is Al-5%Cu with 4% Mg content as wetting agent, and as reinforcement 5 and 10% volume fraction Al2O3 and 5 and 10% of volume fraction SiC is used. The mechanical testing, such as metallography, weight measuring, porosity, SEM/EDS and XRD, is conducted to see the existence of new phase. As the increasing of Al2O3 and SiC content, the mechanical properties, such as hardness in increasing and the wear rate is decrease."

"Bioplastik berbahan dasar pati dan serat alam yang dihasilkan dari penelitian-penelitian terdahulu masih berlum mampu menyamai kualitas plastik konvensional terutama dalam hal kekuatan mekanis, ketahanan terhadap air serta stabilitas termalnya. Penelitian ini bertujuan untuk meningkatkan kualitas bioplastik melalui teknik praperlakuan serat, modifikasi nanofiller dan penggunaan filler hibrid. Bahan baku utama yang digunakan dalam penelitian ini yaitu pati jagung sebagai matriks, serat batang pisang dan selulosa bakteri sebagai filler dan gliserol sebagai plasticizer. Serat batang pisang diberi praperlakuan meliputi metode alkalinasi, bleaching dan enzimatis. Kemudian serat batang pisang yang telah diberi praperlakuan optimum dan selulosa bakteri akan dipreparasi melalui teknik hidrolisis menjadi nanoselulosa. Nanoselulosa serat dan bakteri inilah yang akan digunakan sebagai filler hibrid dalam bioplastik. Bioplastik yang dihasilkan akan dikarakterisasi sifat mekanisnya, laju transmisi uap air, stabilitas termal, dan biodegradabilitasnya. Struktur dari bioplastik dikonfirmasi dengan analisis FESEM, FTIR dan XRD. Praperlakuan serat dan penggunaan nanofiller terbukti mampu meningkatkan karakteristik mekanis dari bioplastik yang dihasilkan dengan persentase nanofiller optimum adalah 15% dari massa pati. Komposisi filler hibrid dengan nilai kuat tarik tertinggi dimiliki oleh bioplastik dengan rasio nanoselulosa bakteri terhadap nanoselulosa serat 50:50 sebesar 1,73 MPa dan untuk modulus Young tertinggi dimiliki bioplastik dengan rasio nanoselulosa bakteri terhadap nanoselulosa serat 25:75 sebesar 60,19 MPa. Penggunaan filler hibrid tidak menghasilkan peningkatan karakteristik mekanis bioplastik tetapi meningkatkan ketahanan terhadap air dan stabilitas termal bioplastik. Ketahanan terhadap air terbaik dimiliki oleh bioplastik dengan filler sebanyak 15% dengan rasio nanoselulosa serat terhadap nanoselulosa bakteri 25:75 yakni laju transmisi uap air sebesar 632 g/m2 per 24 jam. Stabilitas termal terbaik dimiliki oleh bioplastik dengan filler sebanyak 15% dengan rasio nanoselulosa bakteri terhadap nanoselulosa serat 25:75 yakni temperatur trasisi gelas 39,75 °C dan kapasitas panas 0,242 J/g°C. Berdasarikan soil burial test selama 9 hari, diperoleh bahwa bioplastik degan tingkat biodegradasi tertinggi dimiliki oleh pati jagung tanpa filler sebesar 25,76% dan biodegradasi terendah oleh bioplastik dengan filler 15% nanoselulosa bakteri sebesar 18,88%. Soil burial test dilakukan pada kelembaban 66% dan temperatur 26-28 °C.

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Bioplastic based on starch and natural fibre resulted from previous reserachs have not had the same quality as conventional plastic especially in mechanical strength, water absorption resistance, and thermal stability. The objective of this reasearch is to improve the wuality of bioplastic resulted from previous researchs through fibre pretreatment techniques, nanofiller modification, and hybrid filler utilization. The main raw materials that are used in this research are corn starch as matrix, banana pseudostem fibre and bacterial cellulose as filler, and glycerol as plasticizer. Banana pseudostem fibre is treated by alkalinization, bleaching and enzymatic method. Then optimum treated banana pseudostem and bacterial cellulose will be prepared through hydrolysis technique into nanocellulose. These fibre and bacterial nanocellulose will be used as hybrid filler in bioplastic. Bioplastic’s mechanical characteristic, water vapour transmission rate, thermal stability and biodegradability will be characterized. Bioplastic’s structure will be confirmed by FESEM, FTIR, and XRD analysis. Utilization of nanofiller dan fibre pretreatment can improve mechanical characteristic of bioplastic. Nanofiller percentage that resulted in the best mechanical characteristic is 15% from starch mass content. Hybridfiller composition that results in highest tensile strength is obtained by bioplastic with bacterial nanocellulose to fibre nanocellulose ratio 50:50 with value 1,73 MPa and the highest modulus Young is obtained by bioplastic with bacterial nanocellulose to fibre nanocellulose ratio 25:75 with value 60,19 MPa. The best water absorption resistance is obtained by bioplastic with fibre nanocellulose to bacterial nanocellulose ratio 25:75 with water vapour transmission rate value 632 g/m2 per 24 hours. The highest thermal stability is obtained by bioplastic with bacterial nanocellulose to fibre nanocellulose ratio 25:75 with glass transition temperature value 39,758°C and heat capacity 0,242 J/g0C. Based on soil burial test for 9 days, the highest biodegradation rate is obtained by corn starch without filler 25,76% and the lowest by bioplastic with 15% bacterial nanocellulose 18,88%. Soil burial test is done in 66% humidity and temperature 26-28°C."

"In A neural network approach to fluid quantity measurement in dynamic environments, effects of temperature variations and contamination on the capacitive sensor are discussed, and the authors propose that these effects can also be eliminated with the proposed neural network based classification system. To examine the performance of the classification system, many field trials were carried out on a running vehicle at various tank volume levels that range from 5 L to 50 L. The effectiveness of signal enhancement on the neural network based signal classification system is also investigated. Results obtained from the investigation are compared with traditionally used statistical averaging methods, and proves that the neural network based measurement system can produce highly accurate fluid quantity measurements in a dynamic environment. Although in this case a capacitive sensor was used to demonstrate measurement system this methodology is valid for all types of electronic sensors."