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"Diarrheal disease remains an important public health problem in developing countries (Black, 1993) and is enormously associated with one-fourth of all deaths in children less than 5 years in developing countries (Richards et. at, 1993). Despite a remarkable declining in mortality rate, the morbidity rate of acute diarrhea of under five children is still fairly high (Murray, 1992). Alarcon et. al. (1991) reported that each year, diarrheal disease causes approximately more than 1 billion episodes of illness. Therefore, the reported attack rates range from 1 to 12 episodes per child per year with a global average of 3 episodes per child (Richards et. al, 1993) and nearly 5 millions deaths worldwide in children less than 5 years (Shamir, 1998). In Indonesia, the incidence of diarrhea is accounted for up to 200-400 per 1000 population per year; 60-80% of them are under five, mostly infants (Lubis, 1992). Rotavirus is the most common cause of acute diarrheal disease in infants. It is the most commonly identified enter pathogens for infants who admitted to hospital in the USA and many other countries (Saavedra et. al., 1994) included Indonesia, (Soenarto, 1997). In USA accounts for up to 50% of the cases of children hospitalized with diarrhea and dehydration (Cohen, 1991) and is responsible for approximately 1 million cases of severe infantile diarrhea and up to 150 deaths annually (Guarino et.al.,1994). In Indonesia accounts for up to 16% of childhood diarrhea in urban area of North Jakarta and 19-40% of chldhood diarrhea age 0-36 months in Bandung, West Java (Yuwono, 1993). The incidence of diarrheal disease is higher and the severity of the illness is greater in infants than in older children and adults. Several major factors become predisposed to an increased frequency of diarrheal diseases in infants are increased fecal-oral contamination and infants have a relatively unchallenged immune system that has not previously been exposed to many pathogens and has not acquired protective antibodies. Immune system tolerance of life to some polysaccharide antigens in the first year may diminish the infant's ability to defend against intestinal infections (Cohen, 1991). Non-breastfed infants are at greater age of experiencing diarrhea than those who are partially breast-fed, however infants who are partially breast-fed are at greater risk than those who are exclusively breast-fed (Lubis, 1992). The global diarrheal disease control programs have concentrated almost exclusively on the prevention and treatment of dehydration by promoting appropriate fluid and electrolyte therapy, such as increased of oral rehydration solution-ORS (Alarcon, et. al, 1991). ORS has been considered by World Health Organization as the cornerstone of global efforts to reduce mortality from acute diarrhea (Richards et. al, 1993; Behrens, 1993). Until recently, however, more attention has been directed to the nutritional complications of diarrhea (Alarcon, et. al, 1991)."

"Skripsi ini membahahas studi analisis kinerja dari mesin propulsi kapal LNG Tanker menggunakan Combined cycle yang komponennya terdiri dari Turbin gas, Turbin uap, dan Heat recovery steam generator HRSG . Langkah pertama adalah menentukan hambatan tipikal dari kapal LNG Tanker 125.000 m3 menggunakan software ldquo;Maxsurf Resistance 20 rdquo; kemudian dirancang sistem propulsi untuk memenuhi kebutuhan daya dari hambatan tersebut menggunakan software ldquo;Cycle Tempo 5.0 rdquo; dari hasil simulasi didapatkan daya maksimum sistem sebesar 28122.23 kW dengan konsumsi bahan bakar 1.173 Kg/s dan effisiensi sistem sebesar 48.49 pada kondisi muat, kapal dapat mencapai kecepatan 20.67 knot.

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This study explains about performance analysis of a propulsion system engine of an LNG Tanker Ship using Combined Cycle which the components are Gas Turbine, Steam Turbine and Heat Recovery Steam Generator. The first step is to determine the general resistance of an LNG Tanker Ship 125.000 m3 by using Maxsurf Resistance 20 then designing the propulsion system to fulfill the necessary power from the resistance by using Cycle Tempo 5.0 software. The simulation results can indicate the maximum power of system about 28122.23 kW with the fuel consumption about 1.173 Kg s and the system efficiency about 48.49 in full loaded condition, the ship speed can reach up to 20.67 knot."

"ABSTRACTPurpose Adenosquamous carcinoma (ASC) of the pancreas is a rare malignancy, associated with a poor prognosis after surgical resection, with reported median survival times (MSTs) ranging from 4.4 to 13.1 months. We conducted this study to investigate the long-term outcomes of patients after the resection for ASC.MethodsBetween 2002 and 2016, a total of 456 patients underwent resection for ASC or adenocarcinoma (AC) of the pancreas. ASC was confirmed in 17 (3.7%) of these patients. We analyzed the clinicopathological characteristics and survival of these 17 patients in comparison with those of patients with AC of the pancreas.ResultsThe operative procedures performed were pancreaticoduodenectomy (n = 6) and distal pancreatectomy (n = 11). Seven (41.2%) of the 17 patients underwent combined organ resection. R0 resection was achieved in 16 (94.1%) patients. The 5-year overall survival (OS) rate and MST were 40.3% and 20.9 months, respectively. A squamous component of ≥ 60% (P = 0.001) and R1 resection (P < 0.001) were significantly associated with poor OS for patients with ASCConclusionThis study revealed longer survival and a higher R0 resection rate after aggressive combined resection in our ASC patients than those in previous studies. Although this was only a small series, our findings suggest that local control with aggressive resection may be an effective treatment protocol for ASC patients."

"Suatu Opsi untuk meningkatkan efisiensi bahan bakar pada power plant adalahdengan merecovery panas sisa yang keluar dari siklus turbin gas yang dimanfaatkan untukmemproduksi uap. Uap yang diproduksi digunakan untuk meningkatkan daya pada siklusdiatas. Sebagian kecil expansi terjadi pada tingkat pertama turbin diperlukan untuk diextractuntuk meningkatkan air pengisi. Semakin tinggi temperatur air pengisi, semakin kecil heatboiler area. Penambahan daya yang dibangkitkan pada siklus kombinasi pada power plant,sebagai hasil dari recovery panas buang adalah : 27,5 MW dan peningkatan efisiensi thermalsebesar 30% hingga 41 %."

"Dengan kompleksitas tinggi dan kebutuhan dana investasi yang cukup besar maka penentuan asumsi - asumsi menjadi penting pada proyek pembangkit tenaga listrik. Penentuan asumsi ini akan mempengaruhi hasil dari analisis kelayakan financial yang dilakukan untuk menentukan diterima atau ditolaknya proyek. Selain itu analisis sensitivitas terhadap asumsi - asumsi utama perlu dilakukan untuk mengetahui pengaruhnya terhadap kelayakan financial proyek pembangkit PLTGU combined cycle 660 MW. Proyek ini juga menghadapi ketidakpastian akan harga bahan bakar dan tarif energi. Untuk itu perlu dilakukan analisis keputusan manajemen terhadap indikator - indikator kelayakan financial sebelum diambil keputusan terhadap proyek.Metode discounted cash flow digunakan dalam melakukan analisis kelayakan financial proyek PLTGU combined cycle 660 MW untuk mendapatkan indikator NPV dan IRR berdasarkan pendekatan koefisien beta PT ABC. Pendekatan koefisien beta ini penting karena PT ABC belum listing dipasar modal, sehingga hasil analisis diharapakan mendekati kondisi risiko pasar yang sesungguhnya. Asumsi - asumsi yang ditetapkan menjadi input dan economic model yang dibangun untuk melakukan analisis sensitivitas dan kelayakan financial dengan simulasi terhadap skenario pesimis, normal dan optimis untuk loan interest dan discount rate, harga bahan bakar serta capacity factor pembangkit.Analisis sensitivitas memperlihatkan bahwa proyek pembangkit memiliki sensitivitas tinggi terhadap harga bahan bakar gas dan capacity factor pembangkit. Tingkat pengembalian proyek memenuhi target yaitu lebib besar dart discount rate proyek pada harga bahan bakar USD 2,7 - 3 IMMBTU dengan fleksibilitas tinggi pada capacity factor pembangkit. Sedangkan pada harga pasar, USD 5 IMMBTU tingkat pengembalian proyek memenuhi target pads capacity factor 60% keatas dengan soft loan, sedangkan dengan commercial loan target tingkat pengembalian proyek tidak terpenuhi. Soft loan umumnya diperoleh dari pinjaman luar negeri Pcmerintah Republik Indonesia kepada lembaga - lembaga keuangan Intemasioanl seperti ADB dan JBIC yang diteruskan kepada PT ABC. Penerusan pinjaman ini digunakan untuk membiayai proyek - proyek Perusahaan dan tidak diikat jaminan.Dari hasil simulasi terhadap tiga skenario yang ditetapkan memperlihatkan bahwa indikator kelayakan financial proyek PLTGU combined cycle 660 MW memiliki NPV positif pada harga bahan bakar natural gas USD 2,7 - 3,0 IMMBTU dengan dana investasi soft loan dan commercial loan. Untuk harga bahan bakar USD 5 IMMBTU proyek memiliki NPV negatif pada commercial loan, sedangkan dengan soft loan proyek memiliki NPV positif pada capacity factor diatas 60%. atau proyek berada dalam kondisi option zone. Kondisi option zone ini perlu dikaji lebih lanjut sebelum manajemen memutuskan menerima proyek tersebut.Sebagai kesimpulan dari analisis ini adalah penentuan koefisien beta dart PT ABC, perusahaan yang belum listing, menjadi penting agar penilaian proyek PLTGU combined cycle 660 MW mendekati kondisi resiko pasar yang sesungguhnya. Hasil perhitungan, koefisien beta PT ABC adalah 0,74. Analisis keputusan manajemen terhadap indikator kelayakan financial, memperlihatkan bahwa proyek PLTGU combined cycle memiliki tingkat resiko rendah dan layak diterima pada skenario normal dengan loan interest 3,75% dan harga bahan bakar USD 3 MMBTU.

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Power Plant Project is always complicated and involving huge investment therefore selecting proper 'assumptions' on the Financial Analysis is important. Those assumptions will be having direct impact the result of Financial Analysis in order to justify whether the project is feasible of not. On the development of Combined Cycle Power Plant 660MW, the sensitivity analysis on the primary assumptions has to be done to observe its influence toward financial feasibility. Though the project is having high uncertainty on fuel price and energy tariff. It is necessary to analyze the management decisions toward financial feasibility indicators before taking the decision of this project.The discounted cash flow method is used in this Feasibility Study in order to find out the NPV and IRR indicators. It is base on beta coefficient approach of PT ABC. The approach has to be done due to PT ABC is not Public Company yet. This approach will be resulting close to the actual market risk. The assumptions taken, is used for the input data of Economic Mode' established to run the sensitivity analysis and financial feasibility with simulation toward pessimist, normal and optimist scenarios for loan interest, discount rate, fuel price and plant capacity factor.The sensitivity analysis shows that the power plant project has high sensitivity toward natural gas fuel price and plant capacity factor. Internal rate of return of this project is feasible i.e greater than discount rare, at fuel price of USD 2, 7 - 3 per MMBTU with high flexibility of plant capacity factor. Meanwhile at the gas fuel market price USD 5 per MMBTU and soft loan basis, the internal rate of return of this project is feasible on the 60% at plant capacity factor and its not feasible by using Commercial loan. Generally, soft loan come from government loan (government to government) to international financial institution like ADB and JBIC with two stages loan scheme, this loan will be used by PT ABC in financing the entire company project with government guarantee.Refer to the simulation on the three scenarios shows that financial feasibility indicators for 660 MW combined cycle power plant project have positive NPV at natural gas fuel price for 2,7 - 3,0 per MMBTU for both soft loan and commercial loan. At USD 5 per MMBTU of fuel price, the project shows negative NPV at commercial loan and positive NPV at 60% plant capacity factor or more by soft loan. It is mean the project is in the Option Zone. In this Zone, it is necessary to conduct further evaluation before management decides to precede the project.As a conclusion, the determination of PT ABC beta coefficient is important considering they are not Pubic Listed Company. It will make the analysis of 660 MW combined cycle power pant project close to actual market risk condition. The beta coefficient calculation result for PT ABC is 0, 74. An analysis of management decision toward financial feasibility indicators showing that 660 MW combined cycle power plant project is feasible and lower risk by 3,75 % of loan interest and fuel price at USD 3 per MMBTU scenario."

"ABSTRAKDewasa ini, listrik berperan besar terhadap kehidupan manusia. Seakan dengan pertumbuhan penggunaan listrik yang kian bertambah tiap tahunnya, perlu dipertimbangkan mengenai system pembangkitan listrik yang efisien agar setiap energi yang dihasilkan dapat dimanfaatkan sedemikian rupa sehingga jumlah energy yang terbuang (waste energy) dapat ditekan sesedikit mungkin. Penggabungan antara siklus Brayton dengan siklus Rankine dapat menjadi salah satu alternatif untuk meningkatkan efisiensi total mengingat gas buang dari siklus Brayton yang memiliki suhu cukup panas dimanfaatkan untuk memanaskan boiler pada sistem Rankine. Siklus gabungan pun banyak digunakan karena keunggulannya dan salah satunya terpasang di Pembangkit Listrik Tenaga Gas Uap Muara Karang Blok 1 500 MW. Tujuan dari penulisan karya ilmiah ini adalah untuk menghitung nilai efisiensi thermal total serta factor exergy destruction yang mempengaruhi penggunaan energi pada siklus gabungan sebuah pembangkit listirk. Berdasarkan hasil perhitungan dalam keadaan ideal, PLTU MK Blok 1 500MW memiliki efisiensi thermal total sebesar 46.9%, jauh lebih besar jika hanya dijalankan dalam satu siklus yang independen.

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ABSTRACT

Nowadays, electricity plays a major role in human life. As if the growth of electricity usage is increasing every year, it is necessary to consider an efficient electricity generation system so that every energy produced can be utilized in such a way that the amount of wasted energy can be reduced as little as possible. Combining the Brayton cycle with the Rankine cycle can be an alternative to increase total efficiency considering the exhaust gas from the Brayton cycle that has a hot enough temperature is used to heat the boiler in the Rankine system. The combined cycle was widely used because of its superiority and one of them was installed in the Muara Karang Blok 1 500 MW Steam Gas Power Plant. The purpose of writing this scientific paper is to calculate the value of total thermal efficiency and exergy destruction factors that affect the use of energy in the combined cycle of a power plant. Based on the results of calculations in ideal circumstances, MK Sector 1 500MW PLTU has a total thermal efficiency of 46.9%, far greater if it is only run in one independent cycle.

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