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"Tebu merupakan bahan baku untuk membuat gula putih yang merupakan salah satu kebutuhan pokok masyarakat di Indonesia. Tebu yang dipotong ketika panen akan mengalami penurunan kualitas karena kehilangan gula yang terkandung di dalam batang tebu. Kehilangan gula ini akan bertambah seiring dengan lamanya waktu tunda tebu tersebut untuk digiling. Waktu tunda akan menjadi semakin lama apabila terjadi antrian truk di pabrik karena proses bongkar tebu sebelum dilakukan proses penggilingan. Antrian yang terjadi di pabrik gula pada umumnya mengikuti pelayanan FCFS First-Come First Serve . Sistem antrian memiliki beberapa teknik disiplin pelayanan, antara lain disiplin pelayanan dengan prioritas priority service, pelayanan secara acak random order service dan pelayanan dengan kedatangan terakhir Last-Come First-Serve Penelitian ini akan membahas tentang pengaruh disiplin pelayanan terhadap waktu tunda dan pengaruhnya terhadap kualitas bahan baku tebu dengan didukung oleh rancangan penelitian berdasarkan kondisi sistem antrian. Analisis yang dilakukan menggunakan model simulasi sehingga dapat dikembangkan skenario lanjutan untuk memperbaiki sistem antrian di pabrik gula.

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Sugarcane is a raw material for making white sugar which is one of the basic needs of society in Indonesia. Stalks of sugarcane will decrease quality because of the loss of sugar. This losses will increase by the time because of delay time happened in the queue of trucks at the factory due to the process of unloading of sugar cane before the milling process. Queues servce in sugar mills is mostly using first come first serve FCFS dicipline. The queuing system has several service discipline techniques, among others are last come first serve LCFS, services with priority, random service and last come first serve. This research will analysze the delay time and impact on the quality of sugarcane with using design of experiment. Analyzes made using the model simulation which can be used to improve queuing systems at sugar mills. "

"Pada masa Orde baru, muncul program- program agribisnis demi memenuhi kebutuhan pangan Indonesia. Program- program agribisnis ini terangkum dalam sebuah keputusan, yakni Program Tebu Rakyat Intensifikasi atau biasa disebut dengan TRI yang bercita memenuhi kebutuhan gula nasional serta mencapai swasembada gula. Beberapa daerah di seluruh Jawa terkena imbas akibat program ini. Kabupaten Cirebon, Jawa Barat merupakan salah satu daerah yang mendapat program ini. Selama pelaksanaan program TRI, banyak jalan yang harus ditempuh. Di satu sisi pemerintah sudah mempersiapkan programnya dengan baik, di satu sisi para petani merasa baik- baik saja selama pelaksanaan program. Namun hal ini menjadi pertanyaan besar mengapa pada akhirnya di tahun 1997, banyak para petani tebu memilih untuk beralih ke tanaman pangan yang lain dibandingkan dengan tebu.

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During the New Order period, agribusiness programs emerged to meet the needs of Indonesian food. These agribusiness programs are summarized in a decision, namely the Intensification of Smallholder Sugar Cane Program or commonly referred to as TRI that fulfills the national sugar needs and achieves self sufficiency in sugar. Several areas throughout Java were affected by this program. District of Cirebon, West Java is one of the areas that got this program. During the implementation of the TRI program, there are many ways to go. On the one hand the government has prepared the program well, on the one hand the farmers feel fine during the program implementation. But this is a big question why in the end in 1997, many sugar cane farmers chose to switch to other food crops compared to sugarcane."

"Latief AS, Syarief R, Pramudya B, Muhadiono. 2010. Productivity of sugarcane plants of ratooning with various fertilizing treatments. Nusantara Bioscience 2: 43-47. This research aims to determine the sugarcane plants of ratooning productivity with low external input of fertilization treatment towards farmers can increase profits. The method used is the Completely Randomized Block Design (CRBD) with four treatments and three repetitions (4x3). Sugarcane varieties R 579 planted in each patch experiment 5x5 m2. Dosage of fertilizer: P0 = 3.6 kg/year plot experiment was 100% dosage usage of chemical fertilizers used by farmers. Further dosages were P1 (75%) = 2.7 kg/plot, P2 (50%) = 1.8 kg/plot and P3 (0.25%) = 0.9 kg/plot, each supplemented with fertilizer 5 mL of liquid organic/patch a year. Sugarcane crops with a variety of treatment showed no significant difference. The highest productivity was achieved at dosages of P2 (50% chemical fertilizers plus organic fertilizer) is 21.67 kg per square meter. Chemical fertilizers can be saved 7 quintals per hectare a year or Rp 997,500 per year. Additional costs of liquid organic fertilizer Rp.100,000 per hectare year and labor Rp 100,000 per hectare, so the additional advantage of saving farmers fertilizer Rp. 797,500 per year. "

"ABSTRAKTelah dilakukan penelitian mengenai pemanfaatan teknik adaptasi danimobilisasi sel khamir Candida tropicalis InaCC Y799 pada fermentasi xilitol darihidrolisat hemiselulosa daun tebu (Saccharum officinarum L.). Praperlakuan dauntebu dilakukan menggunakan 1,8% asam maleat dan iradiasi gelombang mikropada suhu 180 C selama 5 menit. Penelitian bertujuan untuk mempelajarikemampuan khamir untuk tumbuh dan beradaptasi pada hidrolisat hemiselulosasebelum fermentasi, dan meneliti potensi penggunaan matriks kalsium alginatuntuk imobilisasi sel khamir, serta pengaruhnya dalam peningkatan produksixilitol dari hidrolisat hemiselulosa daun tebu. Hasil menunjukkan bahwa khamirC. tropicalis InaCC Y799 teradaptasi mampu tumbuh pada media hidrolisathemiselulosa daun tebu. Adaptasi khamir pada 75% hidrolisat menghasilkankonsentrasi dan rendemen xilitol maksimum masing-masing sebesar 11,27 1,65g/L dan 0,56 0,05 g/g (54,98% dari nilai rendemen teoritis) selama 24 jamfermentasi, lebih tinggi daripada khamir tidak teradaptasi (kontrol). Namundemikian, imobilisasi C. tropicalis pada kalsium alginat hanya menghasilkankonsentrasi dan rendemen xilitol maksimum masing-masing sebesar 5,51 0,63g/L dan 0,27 0,04 g xilitol/g xilosa awal (29,97% dari rendemen teroritis)selama 48 jam fermentasi. Konsentrasi dan rendemen xilitol pada sistem selterimobilisasi setengah kali lebih rendah daripada sel bebas (kontrol).

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ABSTRACTResearch on adaptation and immobilization method of Candida tropicalisInaCC Y799 in xylitol production from sugarcane (Saccharum officinarum L.)waste hemicellulosic hydrolysate has been conducted. Sugarcane waste werepretreated with 1,8% of maleic acid and microwave at 180 C for 5 minutes. Theaim of this research were to study the effects of yeast adaptation using sugarcanewaste hydrolysate and the potential of using calcium alginate as immobilizationmatrix of yeast C. tropicalis InaCC Y799 in the xylitol production duringfermentation. The results revealed that fermentation using adapted yeast in 75%concentration of hydrolysate produce higher xylitol concentration and yield thanthose with non adapted yeast. The highest xylitol concentration and yield obtainedusing adapted yeast were 11.27 1.65 g/L and 0.56 0.05 g xylitol /g initialxylose (54.98% of theoretical yield) for 24-hours fermentation. However, thehighest xylitol yield obtained by immobilization method were 5.51 0.63 g/L and0.27 0.04 g xilitol/g initial xylose (29.97% of theoretical yield) for 48-hoursfermentation, which were lower than free cells system."

"The definition of the physical and mechanicalproperties of sugarcane trash pellets were necessary for the designconsiderations relating to storage, handling andprocessing equipment. The mixing ratios of groundsugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulkdensity, true density, porosity, durability and compressive strength. The results show that the mixing ratio byweight of 1.0:0.25:0.85 and pelleting speed of 120to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strengthof biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"The definition of the physical and mechanical properties of sugarcane trash pellets were necessary for the design considerations relating to storage, handling and processing equipment. The mixing ratios of ground sugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulk density, true density, porosity, durability and compressive strength. The results show that the mixing ratio by weight of 1.0:0.25:0.85 and pelleting speed of 120 to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strength of biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"Torrefaction, which is used to improve the properties of sugarcane bagasse as fuel in pulverised fuel combustion and as carbon feed in gasification, is a low heating rate pyrolysis of biomass carried out at a temperature of 200–300oC, at an atmospheric pressure, and in an inert environment. In the present work, sugarcane bagasse was torrefied at heating rates of 3, 6, and 10oC/minute, respectively, to achieve a final temperature of 275oC and after the final temperature was reached, hold times of 0 and 15 minutes, respectively occurred at a constant temperature of 275oC for a heating rate of 6oC/minute. The physical characteristics of torrefied sugarcane bagasse samples to be determined were a particle size distribution accomplished by grinding, hydrophobicity by allowing the samples to absorb moisture from the ambient air, and pellet hardness of the sample pellets. The torrefaction results show that increasing heating rate and hold time reduced the cellulose content of the sugarcane bagasse to as low as between 5.35% to 10.61% by weight composition, respectively. As the lignin content increased, the sample pellets resulted in better hardness in comparison to that measured on raw sugarcane bagasse. As the hemicellulose content increased, the samples, after grinding and stronger hydrophobicity, produced a higher fraction of smaller particle sizes. The maximum weight fraction of particles in these samples with sizes smaller than 105 µm achieved was 83.43% weight in contrast to 0.62% weight in raw sugarcane bagasse. The maximum water absorption by the samples in 3 hours was 1.28% weight in contrast to 8.02% weight by raw sugarcane bagasse. The results indicate that torrefaction is able to improve sugarcane bagasse physical characteristics, which are favourable for biomass pelletization, storage and transportation."

"Thionic Fluvisols soil in Southern Vietnam is like typical acid sulfate soil in the tropics and is severely polluted due to human activities. Salinity intrusion and industrial wastewater contamination are the main cause of environmental degradation in soil ecosystem. This research was aimed to determine a link between biochemical soil properties and land use types to provide suitable solutions for afforestation and soil restoration. Soil sampling was conducted in five different land use types at four soil layers (O, AB, Bj and Cp). The five land use types were sugarcane crop; Melaleuca plantation; 2-year Acacia plantation; 5-year Acacia plantation; and control (grass-covered land). The results showed that soil in those five land use types were very acidic (pH ≤ 4) having poor-nutrient condition with  range of  orthophosphate  content of 378 - 640 mg/kg, N-NH4  of 586 - 999 mg/kg and N-NO3 of 830 - 1,112 mg/kg. Concentration of toxic ions was very high with large variation among land use types and soil depths i.e. 1,799 – 12,403 mg SO42-/kg; 22 - 1,645 mg exchangeable Fe/kg and 34 - 88 mg Al3+/kg soil. The lowest concentration of exchangeable Fe3+ and SO42- ions were found in sugarcane and Melaleuca plantations, respectively. Twenty-three sulfur-oxidizing bacteria and two iron-oxidizing bacteria were identified. All these bacteria were initially identified as Thiobacillus sp. Sugarcane and Melaleuca plantations exhibited the most diverse Thiobacillus species which linked to reduction of exchangeable Fe and SO42- concentrations in these two land use types. This study indicated that Thiobacillus sp. could grow well in the Thionic Fluvisols. It is proposed that Melaleuca and sugarcane species could reduce iron and sulfur contents in Thionic Fluvisols in the tropics"