Judul: Efficiency Production of National Sugar Mills.
Abstrak: The sugar factory is one of the strategic industries in Indonesia because of the sugar mill output can meet the basic food needs, the needs of other industries, and providing jobs. In fact the national sugar production can not meet national sugar consumption. Sugar mills can not increase the production of sugar because sucrose levels which are necessary for the production of sugar lost. Loss of sucrose as seen from yield of sugarcane based on information from other studies due to the machines are old, relatively low production capacity, raw materials predominantly owned by the people, and infertile land outside Java. Therefore, the purpose of this study was to measure the efficiency of the national sugar factories, tracing factors and determinants measure the efficiency of the national sugar mill. To answer these objectives, this study uses panel data from 26 sugar factories by the use of data envelopment analysis models (DEA) and random effects. The results showed the national sugar factory is inefficient due to the inefficiency of 6.70 percent from 2006 to 2011. Inefficient sugar mills which shows the ratio of input and output is relatively higher than other sugar mills. Sugar mill production capacity of small and medium production capacity is not efficient when compared with large production capacity. That is because the use of the cane, labor, production capacity, and the fuel is relatively high in both sugar factory. Relatively high input use also occurs at the sugar factory machine age of 30 years instead of the sugar mill sugar mill machinery under the age of 30 years. Sugar factories outside Java is more efficient than the sugar mills of Java in terms of employment and low fuel. However, the issue of fertile land in Java is not proven because the yield of sugarcane is not any difference in both the sugar factory.Assessment of managerial factors influence the machine age factor, the yield of sugarcane/sugarcane itself is negatively related to production capacity efficiencies while factors are positively related to efficiency. Factors that do not affect the efficiency of the sugar contained in the plant site. It is stated that the location of the sugar mills in Java and outside Java no relationship with efficiency. Efforts to increase the efficiency can be done by the turn of the engine and increased production capacity simultaneously. However, the effort if done synchronously definitely face great problems in funding and procurement of sugarcane. Therefore, efforts to increase the efficiency of the two lies only at the turn of the engine. Substitution is done with a machine that is a picture of the target input in the sugar factory managers in using the input. Sugar factories belonging to the people of the dominant raw material can increase the yield of sugarcane planting schedule and milled if done simultaneously and the use of seed cane that keprasan maximum of three times. It is based on sugarcane cultivation techniques clue owned sugar mills.
Keyword: Efficiency, National Sugar Mill, Machine, Sugarcane.

Judul: Efisiensi Teknis Produksi Usahatani Tebu Jawa – Luar  Jawa: Pendekatan Stochastic Frontier Analysis
Abstrak: Sugar cane is the main ingredient in the production of sugar which is consumed by the majority of Indonesian people. This commodity has a vital role in various aspects such as economic, social, and political. In providing the need for sugar, there needs to be good planning so that various upheavals do not occur. Sugarcane production produced by farmers for a decade has significantly increased to reach an average growth of 0.84 percent. Meanwhile, the sugarcane harvested area, which is the main factor in production, has dramatically decreased with an average growth of -0.05 percent since 2012. The decreasing harvested area is a concern in maintaining Indonesia's sugarcane production. However, the Sugar Factory (PG) requires a large harvest area for sugar production, accounting for 20 thousand ha to produce 10 thousand tons of sugar per day, thus causing a critical concern in population growth. In increasing production with continuously decreasing land conditions, it is necessary to use the Intensification method. The island of Java is dominating sugarcane production in Indonesia, which in the long term, it will no longer be able to contribute to production due to the conversion of agricultural land to non agricultural use and the level of technical efficiency in the current sugarcane farming production which has been almost well-developed. This condition is an alternative for the development of more agricultural areas outside Java Island. There are 10 provinces outside Java, namely Lampung, South Sumatra, Aceh, West Nusa Tenggara, Gorontalo, East Nusa Tenggara, North Sumatra, Bali, South Sulawesi and Southeast Sulawesi and 4 provinces in Java, namely East Java, Central Java, West Java, and DI Yogyakarta which have become targeted areas for the development of sugar cane based on PERMENTAN NO. 18 of 2018. This study aims to analyze and discuss the level of technical efficiency of sugar cane farming in Java and outside Java. The performance of sugarcane farmers in Java - Outside Java is seen from the level of technical efficiency which can indirectly describe the performance of sugarcane farmers in the development of sugarcane areas. The data used in this study is secondary data in the form of cross sections. The research data comes from the results of the 2014 Sugar Cane Business Household Survey which is part of the results of the 2013 Central Statistics Agency Agricultural Census with code ST2013-SKB.S. The research data were analyzed using a technical inefficiency model on the Cobb-Douglas stochastic frontier production function to see the characteristic and socioeconomic factors that influence inefficiency. Based on the research results in achieving maximum output, land, seeds with nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, and labor have a significant effect on Java Island, whereas the harvest area, seeds, and fertilizer elements of phosphorus become crucial factors outside Java Island. Among the variables concerned, land has the highest coefficient for Java Island. It shows that the increase in harvested area in Java is 4 times greater in producing production compared to outside Java. Increased harvested area is closely related to extensification. This is more likely to be done outside of Java. In this case,
Keyword: institution, stochastic frontier production function, sugarcane area, sugarcane farming, technical efficiency

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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