Judul: Comparison of the Level of Effectiveness of Duration Strategies in Immunization of Corporate Bond
Abstrak: Imunisasi merupakan suatu strategi yang digunakan oleh investor dalam rangka melindungi obligasi dari risiko tingkat suku bunga dengan cara menyamakan durasi portofolio dengan holding period yang diharapkan oleh investor. Konsep durasi menjadi kunci dalam melakukan imunisasi. Durasi Macaulay dan durasi yang dimodifikasi merupakan konsep durasi yang paling sering digunakan. Karya ilmiah ini membahas bagaimana perubahan tingkat suku bunga akan memengaruhi obligasi serta mengilustrasikan bahwa konsep durasi Macaulay dan durasi yang dimodifikasi dapat mengimunisasi portofolio obligasi dari risiko tingkat suku bunga. Aset obligasi yang diteliti adalah obligasi korporasi yang diterbitkan pada tahun 2018, dan perubahan tingkat suku bunga yang digunakan adalah penurunan tingkat suku bunga yang terjadi pada bulan Juli 2019. Berdasarkan hasil penghitungan, perubahan tingkat suku bunga memiliki hubungan yang berbanding terbalik dengan harga obligasi, serta strategi durasi yang dimodifikasi memiliki hasil yang lebih efektif dalam mengimunisasi portofolio obligasi korporasi dari risiko tingkat suku bunga dibandingkan dengan durasi Macaulay., Immunization is a strategy used by investors in order to protect bonds from the risk of fluctuating by equating the duration with the holding period expected by investors. The concept of duration is vital in immunization. Macaulay’s duration and modified duration are the most commonly used duration concepts. This thesis discusses how changes in interest rates will affect bonds and illustrates that the concepts of Macaulay’s duration and modified duration can immunize a bond from interest rate risk. The bond assets studied are corporate bonds issued in 2018, and the changes in interest rates used are interest rate reductions that occurred in July 2019. Based on the calculation results, changes in interest rates have an inversely proportional relationship with bond price, and modified duration strategy has a more effective result in immunizing corporate bond from interest rate risk compared to Macaulay’s duration.
Keyword: bond corporation, immunization, interest rate risk, Macaulay's duration, modified duration

Judul: Optimasi Portofolio Obligasi Yang Terimunisasi Dengan Goal Programming, Optimization of immunized bond portfolios using goal programming
Abstrak: In a term investments, portfolio is defined as a collection of securities, i.e. real or financial assets. Portfolio can bo arranged in a form of bonds of stocks. Bonds are considered as types of securities that have smaller risk than stocks. Based on the type, the bond are devided into goverment and corporate bonds. The risk of bonds is obtained from the risk of interest rate swing, maturity, and default risk that exist on each bond. Those risks affect the rate of return equal to or grater than the purchase price of the bonds. Therefore, the concept of immunization is introduce to reduce the level of riskc in the portfolio composed by various types of bonds. In the immunized bond portfolio the risk that exist on the bonds will be minimized so that the rate of return obtained by investors in the future will be maxmized. The implementation of optimizing the immunized bond portfolios is carried out using goal programming with LINGO 11.0. The result of this optimizztion id the proportion of immunized bond portfolios which gives maximal return and minimal risk over a particular investment period.
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Judul: Design of gathering-conveying unit of mobile sugar cane trash chopping machine
Abstrak: A machine for gathering and chopping the piles of sugarcane trash on the field after harvesting is being designed. As a part of the machine, a gathering-conveying unit was designed. Important data including condition and characteristics of trash were collected and used for designing the unit. The average bulk density of trash on the field was 7.7 kg/m3, the average pressure to compress the trash from 40 cm to 30 cm thickness was 50.65 N/m2, and the pressure to compress the trash from 27 cm to 8 cm thickness was 1166.60 N/m2. The unit was designed to be operated at 0.3 m/s forward speed, and having 60 cm working width. The unit was consisted of: a gathering reel, a pair of conveyors, cover-frame and power transmission components. Size and operational speed of moving components were determined by analyzing mass flow rate of the trash, and operating power of the components. The gathering reel was 100 cm in diameter and having 4 series of gathering fingers for drawing and feeding the trash into the conveyors. A pair of chain-conveyors equipped with L-shaped steel bars was set face to face on lower side and upper side for conveying and feeding the leaves to the chopping unit. The stationary test showed that the gathering reel and the conveyors could work properly. The average rotational speed of the conveyor shaft and the gathering reel were 34.03 rpm and 9.97 rpm, respectively. The working capacity of the unit was 400-500 kg/hour.
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