Judul: Modifikasi desain dan uji unjuk kerja mesin pengempa briket semi mekanis tipe kempa ulir (screw pressing)
Abstrak: Energi merupakan bagian yang paling penting dalam setiap kegiatan manusia. Konsumsi energi di Indonesia semakin lama semakin meningkat seiring dengan bertambahnya jumlah penduduk dan peningkatan kebutuhan energi di segala sektor terutama sektor industri dan pertanian. Selama ini bangsa Indonesia sangat tergantung pada energi yang berasal dari fosil. Padahal semakin lama energi tak terbarukan ini semakin menipis ketersediaannya. Penandatanganan kebijakan energi oleh Presiden Indonesia pada Februari 2006 semakin menyadarkan kita akan pentingnya pemanfaatan energi alternatif terbarukan.
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Judul: Pengembangan Konsep Desain Pengempa Briket Semi Mekanis Tipe Kempa Ulir untuk Arang Tandan Sawit Kosong
Abstrak: . Empty bunches from palm were waste with high benefit but less used optimum. One of the way to increase the benefit from this waste was to use it as the raw material of bunches briquette. Making of briquette pressing machine was used to increase the better quality of briquette. Types of briquette machine were regular pressing tool, mechanic pressing tool and hydraulic pressing tool. The objective of this research was to develop the previous design of briquette pressing machine into machine which can work in optimum. On this research has modified from previous machines owned by Endah Marwati (2006) and Irwan Darmawan (2008). Design modification has create a design of briquette pressing machine semi mechanic type of screw pressing with power needed for 7.453 Watt hour/kg less than if compared with Irwan darmawan’s power needed as 17.1486 Watt hour/kg while Endah Marwati power needed for 10.6734 Watt hour/kg. This was caused by the certain modification especially on briquette pressing part both material and dimension. Besides that, the characteristic of briquette raw material affected the pressing process. This was also indirectly affected level power needed by that machine, the harder material and the more material needed to be pressed there will increase the needed of power
Keyword: briquette pressing, design, briquette

Judul: Quantitative Trait Loci Mapping for Trait in Categorical Scale
Abstrak: Genes or regions on chromosome underlying a quantitative trait are called Quantitative Trait Loci (QTL). Characterizing genes controlling quantitative trait on their position in chromosome and their effect on trait is through a process called QTL mapping. In estimating the QTL position and its effect, QTL mapping basically utilize the association between QTL and DNA markers. However, many important traits are obtained in categorical scale, such as resistance from certain disease. From a theoretical point of view, QTL mapping method assuming continuous trait could not be applied to categorical trait. This research was focusing on the assessment of the performance of Maximum Likelihood (ML) and Regression (REG) approach employed in QTL mapping as well as the performance of Lander and Botstein (LB) and Piepho method in determining critical value in testing the existence of QTL for binary and ordinal trait by means of simulation study. The simulation study to evaluate the performance of ML and REG approach was conducted by taking into account several factors that may affecting the performance of both approaches. The factors are: (1) marker density; (2) QTL effect; (3) sample size; (4) shape of phenotypic distribution; (5) number of categories; and (6) number of QTL. Moreover, the simulation study for evaluating LB and Piepho method in determining critical value was conducted by generating distribution of the test statistic under null hypothesis. From simulation study, it was obtained that LB and Piepho method showing similar performance in determining critical value in testing the existence of QTL for binary and ordinal trait. The simulation study also indicating that both methods could be used in determining critical value in QTL mapping analysis for binary trait as well as for ordinal trait if the REG approach is used but not if ML approach is used due to their poor performance. In assessing the performance of ML and REG approach in QTL mapping analysis for binary trait, the two approaches showing comparable performance; whereas for ordinal trait REG approach showing poor performance compared with ML approach in estimating thresholds. As a result, in QTL mapping analysis, ML and REG approach could be used when dealing with binary trait, whereas ML approach is suggested when dealing with ordinal trait.
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