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Tjiu W.,National University of Malaysia | Marnoto T.,National University of Indonesia | Mat S.,National University of Malaysia | Ruslan M.H.,National University of Malaysia | Sopian K.,National University of Malaysia
Renewable Energy | Year: 2015

This paper presents several multi-megawatt offshore Darrieus vertical axis wind turbine (VAWT) projects currently under way. The projects are re-attempting large scale VAWT since Eole, the only multi-megawatt Darrieus VAWT ever built, which was shut down in 1993. In addition, the project's timing is at the moment when horizontal axis wind turbine (HAWT) is facing major challenges in multi-megawatt range, especially for offshore wind power generation. The obstacles of large scale HAWT are elaborated, and the reasons of why Darrieus VAWT is key to the challenges are also explained. In addition, impacts of HAWT development on Darrieus VAWT are described. Lastly, the innovative designs on Darrieus VAWT are presented, which include current status of Sandia National Laboratories (SNL), novel offshore vertical axis (NOVA), Vertax and Vertiwind. © 2014 Elsevier Ltd. Source


Majeri Mangunjaya F.,National University of Indonesia | Elizabeth McKay J.,University of Kent
Worldviews: Environment, Culture, Religion | Year: 2012

In this paper, the authors argue that while state-sponsored efforts to preserve Indonesia's natural resources have been needed, their effectiveness has been limited due to the paucity of available arable land and the frequent conflicts conservation policies have generated among local populations. Rather than a top-down structural approach, they argue, what is needed is an innovative approach that includes education at the grassroots, which in Indonesia will combine Islamic principles of environmental protection with traditional methods of conservation. After a section presenting an Islamic theology of creation care and then highlighting some projects in the Muslim world, the spotlight is turned on Indonesia, where a number of initiatives involve the cooperation of religious leaders, eco-friendly pesantren (religious boarding schools), international NGOs, and government policy at the national and regional levels. © 2012 Koninklijke Brill NV, Leiden. Source


The family Acidopsidae Števčić, 2005, is revised; and two subfamilies are recognised. The Acidopsinae Števčić, 2005, is characterised by the coxal male opening, a quadrate basal antennal article and vulvae arranged near the median longitudinal thoracic sternal groove. Three genera are included in the Acidopsinae: Acidops Stimpson, 1871 (with two species), Parapilumnus Kossmann, 1877 (with two species) and Crinitocinus gen. nov. (monotypic for Pilumnus alcocki Borradaile, 1902). The Raouliinae Števčić, 2005 (= Typhlocarcinodidae Števčić, 2005; Caecopilumnidae Števčić , 2011), is characterised by its coxo-sternal male opening, a short basal antennal article which is distinctly wider than long and vulvae arranged submedially on thoracic sternite 6. Four genera are included in the Raouliinae: Raoulia Ng, 1987 (with five species, three of which are described as new), Caecopilumnus Borradaile, 1902 (with three species of which one is described as new), Typhlocarcinodes Alcock, 1900 (monotypic) and Thecaplax gen. nov. (for one new species). © Copyright 2014 Magnolia Press. Source


Sulaksono A.,University of Indonesia | Satiawati L.,National University of Indonesia
Physical Review C - Nuclear Physics | Year: 2013

The density-dependent lepton fractions approach that is used to describe the properties of matter with neutrino trapping is systematically studied. It is found that two sets of the ratio of trapped neutrinos to leptons parameters - i.e., one for a relativistic mean field parameter set with stiff equation of state and one for a parameter set with soft equation of state - yield particle composition profiles at high densities similar to those predicted by the standard fixed lepton fraction approach. However, these sets of parameters produce significantly different behavior at low densities compared to those of standard approach. The consequences of applying the density-dependent lepton fractions approach to some properties of PNS, such as the particle composition, equation of state, the onset of low-density instability, the mass-radius relation, and the mean free path of electron neutrino, are investigated. By comparing the results with those of the standard approach, we obtain the result that the PNS equation of state is not significantly influenced by the low-density behavior difference between the two approaches. However, the density-dependent lepton fractions approach yields a smaller onset of low-density instability matter and core-crust transition density but a slightly larger maximum mass as well as a larger radius of canonical mass than those predicted by the standard approach. The estimated minimum PNS mass and its radius are apparently also sensitive to the parameter used for the ratio of trapped neutrinos to leptons. For electron neutrino transport in PNSs, matter with density-dependent lepton fractions is more transparent than matter with fixed lepton fractions. © 2013 American Physical Society. Source


van Noordwijk M.A.,University of Zurich | Willems E.P.,University of Zurich | Utami Atmoko S.S.,National University of Indonesia | Kuzawa C.W.,Northwestern University | van Schaik C.P.,University of Zurich
Behavioral Ecology and Sociobiology | Year: 2013

In most mammals, females pay for reproduction by dramatically increasing net energy intake from conception to mid- or late lactation. To do this, they time their reproductive events in relation to environmental cycles so that periods of peak food availability coincide with peak demand or are used to build energy stores. This timing is not possible in species with slow development in which lactation is prolonged over a multi-year period with fluctuating food availability. Here, mothers are expected to sustain a stable but generally lower level of nutrient transfer. In a sample of over 1,050 complete follow days of eight mother-infant pairs collected over 7 years, we document maternal effort for wild Bornean orangutans (Pongo pygmaeus wurmbii) over their average 6. 5-year lactation period. As predicted, maternal feeding time was independent of the age of her growing offspring, indicating a stable sustained "plateau" effort of ≤ 25 % above baseline level, instead of a short peak lactation as seen in seasonal breeders. Infant orangutans started to regularly supplement milk with self-harvested food when they were 1-1. 5 years old, indicating milk intake was insufficient from this age onwards, even though maternal effort did not decrease. We expect the same regulation of sustained maternal effort in other large and large-brained mammals with slow infant development. We also predict that mother-infant conflict over suckling may show another peak at the onset of the milk + solid food phase, in addition to the well-known conflict around the endpoint of lactation (weaning), which is reached after a long and gradual increase in solid food intake by the infant. © 2013 Springer-Verlag Berlin Heidelberg. Source

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