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Abstrak :
A range of microstructure as a result of low-temperature crystallization of amorphous alloy based on the composition Fe68Cr18Mo2B12 prepared by chill block melt spinning casting has been investigated using x-ray diffractometer and transmission electron microscope. Low-temperature crustallization of the amorphous alloy produced a very fine microstructure consisting of Fe; body centered tetragonal Fe3B and a small proportion of orthorhombic Fe3B. The body centered tetragonal Fe3B was found to contain fine and coarse faults with lead to streaking in selected area diffraction patterns. The crystallization of the present material is proposed to occur by primary crystallization of solid solution ferritic phase followed by a eutectic reaction of Fe+Fe3B.

Abstrak :
Materials Science in Construction" explains the science behind the properties and behaviour of construction's most fundamental materials (metals, cement and concrete, polymers, timber, bricks and blocks, glass and plaster). In particular, the critical factors affecting in situ materials are examined, such as deterioration and the behaviour and durability of materials under performance. An accessible, easy-to-follow approach makes this book ideal for all diploma and undergraduate students on construction-related courses taking a module in construction materials.

Abstrak :
Nilai tukar dipercaya memiliki pengaruh signifikan dalam perekonomian Indonesia. Dengan asumsi tersebut, maka pengetahuan mengenai kondisi makro ekonomi dan mikrostruktur pasar valas menjadi sangat penting bagi pembuat kebijakan. Penelitian ini, difokuskan pada analisis kondisi mikrostruktur pasar valas Indonesia dan dampaknya terhadap fluktuasi nilai tukar Rupiah. Namun, mengingat selama periode penelitian (2008-2013) terdapat beberapa potensi structural break, maka selain mengaplikasikan metode uji ko-integrasi, VECM, Granger Causality, dan Impulse Response Function, serta OLS untuk mengkonfirmasi hasil penelitian, juga akan digunakan metode Zivot-Andrews dan Gregory-Hansen, serta uji BLUE. Hasil penelitian menunjukan seluruh metode yang digunakan memberikan hasil yang konklusif, bahwa permintaan valas korporasi domestik, suplai valas investor asing dan sentiment regional Asia signifikan mempengaruhi volatilitas nilai tukar Rupiah, Lebih lanjut, permintaan valas korporasi domestik merupakan faktor dominan yang mendorong Rupiah terus terdepresiasi, sehingga sangat dibutuhkan bauran kebijakan untuk memperbaiki kondisi tersebut. ...... The exchange rate is believed to have significant influence in Indonesia's economy. With that assumption, the knowledge of the macro-economic conditions and the microstructure of the foreign exchange market is becoming very important for policy makers. This study, focused on the analysis of the microstructure of foreign exchange market conditions in Indonesia and its impact on the fluctuation of the Rupiah exchange rate. However, given during the study period (2008-2013) there are several potential structural break, then in addition to applying the method of cointegration test, VECM, Granger Causality and Impulse Response Function, as well as OLS to confirm the results of the research, the method will also be used Zivot-Andrews and Gregory-Hansen, and BLUE test. The results showed all the methods used provide the conclusive results, that the domestic corporate demand for US Dollar, the supply of US Dollar from foreign investors and Asian regional sentiment significantly affect the fluctuation of the Rupiah exchange rate. Furthermore, the demand of US Dollar from domestic corporations is the dominant factor driving the rupiah continued to depreciate, so that the policy mix is needed to improve the condition.

Abstrak :
ABSTRAK Penelitian ini memeriksa hubungan cross-sectional antara turnover shock saham di sesi perdangangan pasca-penutupan IDX dan efisiensi harga pembukaan. Hasil penelitian menemukan adanya pelemahan efisiensi harga pembukaan pada transaksi pembuka. Hal ini konsisten dengan resiko information asymmetry. Penelitian ini juga mendukung argumen bahwa resiko information asymmetry tidak berkaitan dengan market friction walaupun kedua faktor tersebut behubungan dengan mikrostruktur harga aset dan bahwa ketersediaan opening call auction pada saham-saham paling liquid mungkin tidak meningkatkan efisiensi harga pembukaan saham-saham tersebut.

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ABSTRACT This paper examines cross-sectional relationship between stocks? magnitude of turnover shock in IDX post-close trading session and their price efficiency in the opening. The result confims that the shock is significantly decreasing opening price effeciency in the opening trade. This finding is consistent with information asymmetry risk. Additionally, this research confirms that information asymmetry risk is unrelated to market friction although both of them are related to microstructure asset pricing and that availability of opening call auction in stocks with highest liquidity may not improve their opening price.

Abstrak :
Tujuan utama tesis ini adalah untuk mengetahui pola perdagangan saham intrahari ditinjau dari return dan volatilitasnya, mengetahui adanya day of the week effect dan time of the day effect serta melihat perbedaan return antar hari perdagangan dan antar interval waktu 30 menit pada 5 fraksi perdagangan di Bursa Efek Indonesia. Hasil penelitian ini menunjukkan bahwa return kelima kelompok fraksi perdagangan membentuk kurva yang tidak seragam. Return kelompok fraksi perdagangan Rp1 membentuk kurva W, kelompok fraksi perdagangan Rp5, Rp10 dan Rp25 membentuk kurva J sedangkan kelompok fraksi perdagangan Rp50 membentuk kurva U. Ditinjau dari volatilitasnya, kelima kelompok fraksi perdagangan membentuk kurva yang sama yaitu kurva U. Dengan adanya perbedaan pola perdagangan ini maka investor dapat menetapkan strategi investasi yang tepat yaitu waktu terbaik untuk melakukan transaksi (buy/sell) dan kelompok fraksi saham yang direkomendasi dan yang dihindari. Selain itu penelitian ini juga membuktikan adanya pengaruh signifikan dari pergerakan return saham baik berdasarkan periode hari maupun interval waktu 30 menit terhadap return saham. Dengan demikian hal ini membuktikan adanya day of the week effect dan time of the day effect pada semua kelompok fraksi perdagangan. Penelitian ini juga membuktikan adanya perbedaan return yang signifikan baik antar hari perdagangan maupun antar interval waktu 30 menit. ......The main objective of this thesis is to determine stocks Intraday trading patterns in terms of returns and volatility by examining the day of the week effect and time of the day effect as well as investigating the return difference among trading days and among interval of 30 minutes for 5 fractions of trading in the Indonesia Stock Exchange. The results indicate the return curves of the five trade fractions group are not similar. The returns of trade fraction group Rp1 form W-curve, trade faction group Rp5, Rp10 and Rp25 form J-curve, while trade fraction group Rp50 form the U-curve. However, the volatility of the five groups forms identical curve that is U-curve. By taking into account the differences in the pattern of trade, investor can determine proper investment strategy that is the best time to do the transaction (buy/sell) and the fraction of shares that are recommended and which to avoid. In addition, this study demonstrates the existence of significant influence from either the movement of stock returns based on the period of the day and 30-minute intervals of stock return. Thus, the evidence supports the existence of day of the week effect and time of the day effect on all groups of trading fraction. The findings show the existence of significant return differences either between day trading and inter-interval time of 30 minutes.

Abstrak :
ABSTRAK Baja tahan karat dua fasa SAF 2205 pipa kelas 65 diberikan perlakuan cold pilgering menyebabkan kelasnya meningkat menjadi kelas 140 dan kekuatan luluhnya juga meningkat. Meningkatnya kekuatan luluh ternyata menurunkan ketangguhan material. Diberikan perlakuan panas untuk meningkatkan ketangguhan tersebut dan diharapkan sifat mekanisnya mendekati kelas 125 atau 110. Diberikan perlakuan panas dengan suhu 350 ̊C, 450 ̊C dan 550 ̊C dengan waktu tahan 30 dan 40 menit. Setelah diberikan perlakuan, diperiksa sifat mekanisnya dengan pengujian tarik, impak, keras dan metalografi. Didapatkan parameter optimum untuk mendapatkan ketangguhan yang optimum pada suhu 550 ̊C dengan waktu tahan 30 menit.

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ABSTRACT Duplex stainless steel SAF 2205 grade 65 given cold pilgering treatment that increase their grade to grade 140 and increase the yield strength. Increasing yield strength, lowering the toughness of material. Heat treatment given to material to increase the toughness and make the mechanical properties closer to grade 125 or 110. Heat treatment parameter that been used are 350 ̊C, 450 ̊C, and 550 ̊C with holding time 30 and 40 minutes. After heat treatment, the mechanical properties checked with tensile test, impact test, hardness test and metallography. The optimum parameter for the optimum toughness is reached in temperature 550 ̊C with holding time 30 minute.

Abstrak :
In the present study, natural fibers located in thick outer woody rinds of the metroxylon sago (MS) tree were investigated. The investigation focused on measuring the mechanical properties and observing the microstructures of MS fibers before and after treatment with 5% sodium hydroxide. A scanning electron microscope was used to observe the microstructure of MS fiber, and the results showed that there was a decrease in fiber diameter after mercerization. A porous structure in the cross-section area of untreated fibers was clearly seen, and it was highly compressed after mercerization. The strength of MS fiber increased significantly after it was treated by 5% NaOH solution for two hours. The average ultimate strength of untreated MS fiber was recorded as 46 MPa; treatment with sodium hydroxide resulted in a significant increase in average ultimate strength to 163 MPa. Additionally, the elastic modulus of treated fiber was greater than that of untreated fiber.

Abstrak :
Perubahan struktur mikro baja karbon rendah menyebabkan terjadinya perubahan sifat. Perubahan ini sangat dipengaruhi oleh bentuk dan jenis pengerjaan (perlakuan) yang diberikan atau yang dialami oleh baja tersebut, bentuk dan jenis pengerjaan umumnya berupa pengerjaan panas atau pengerjaan dingin. Telah dilakukan penelitian pada konstruksi sambungan las dari bahan lembaran baja karbon rendah spesifikasi Ship Plate BKI Grade "A" hasil pengerolan panas produksi PT. Krakatau Steel, dengan menggunakan las SMAW dalam kondisi arus dan kecepatan pengelasan yang konstan. Dalam penelitian ini diambil dua jenis spesimen yang berbeda masing-masing spesimen yang tidak mengalami proses pengelasan dengan variasi sudut antara arah roll dan arah sumbu panjang spesimen masing-masing diambil 0° , 45° dan 90° dan spesimen yang mengalami proses pengelasan dengan variasi sudut arah roll terhadap arah las, masing-masing diambil 0° , 45° dan 90°. Pada penelitian ini dilakukann pengujian mekanik antara lain uji tarik, uji kekerasan, uji impact, pengukuran besar butir, uji metalografi, uji kekasaran permukaan, uji korosi serta struktur fasa dan bentuk butir. Berdasarkan hasil pengujian tersebut diatas didapatkan kekuatan tarik terbesar (6u) = 46,33 kg/mm2, kekuatan luluh (ay) = 31,74 kg/mm2 elongation (e) = 41,66 %, kekuatan impact (HI) = 1,525 J/mm2, kekerasan (Hv) = 200 pengurangan massa (R) = 1,212 mm/yr dan kekuatan tarik terkecil (6u) = 37,76 kglmm2, kekuatan luluh (ay) = 27,02 kg/mrn2, elongation (e) = 09,50 %, kekerasan (Hv) = 160,70, kekuatan impak (HI) = 0,0128 J/mm2 dan pengurangan massa (R) = 0,0641 mm/yr. ......The change of microstructure low carbon steel to cause alteration property. This alteration very influenced by model treatment quality which receiving or to experienced by steel mentioned this type or sort working was generally hot working which cold working. The investigation or-welding joint construction according to material low carbon steel spesification "Ship Plate BKI Grade A" hot rolling produce PT. Krakatau steel with applying SMAW weld in current condition and welding speed which constant According to investigation used two speciment type which to differ severally that not to experience welding proms for angle variation direction gap to rolling and and length pith speciment to take severally 0°, 45° and 90° and the speciment which to experience welding process with rolling direction to wards weld metal course, for severally to used 0°, 45° dan 90°. According to this investigation to executed mechanic testing among ather things tension test, hardness test impact test grain measuring, metallography test surface roughness test and corrosion test, besides from that possible too grain model and fasa structure° To be found result test mentioned to find the highest tension stress (au) = 46,33 kg/mm2, yield stress (cy) = 31,74 kglmm2, elongation (e) = 41,66 %, impact stress (Hi) = 1,525 J/mm2, hardness (Hv) = 2110 and to decrease of mass (R) = 1,212 mm/yr, and the lowest tension stress (cu) = 37,76 kg/mm2, yield stress (ay) = 27,02 kg/mm2, elongation (e) = 09,50 %, hardness (Hv) = 160,70, impact stress (HI) = 0,0128 J/mm2, and to decrease of mass (R) = 0,0641 mm/yr.