Search results for: Abualseoud Hanani
4 Routing in IP/LEO Satellite Communication Systems: Past, Present and Future
Authors: Mohammed Hussein, Abualseoud Hanani
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In Low Earth Orbit (LEO) satellite constellation system, routing data from the source all the way to the destination constitutes a daunting challenge because LEO satellite constellation resources are spare and the high speed movement of LEO satellites results in a highly dynamic network topology. This situation limits the applicability of traditional routing approaches that rely on exchanging topology information upon change or setup of a connection. Consequently, in recent years, many routing algorithms and implementation strategies for satellite constellation networks with Inter Satellite Links (ISLs) have been proposed. In this article, we summarize and classify some of the most representative solutions according to their objectives, and discuss their advantages and disadvantages. Finally, with a look into the future, we present some of the new challenges and opportunities for LEO satellite constellations in general and routing protocols in particular.Keywords: LEO satellite constellations, dynamic topology, IP routing, inter-satellite-links
Procedia PDF Downloads 3823 Implied Adjusted Volatility by Leland Option Pricing Models: Evidence from Australian Index Options
Authors: Mimi Hafizah Abdullah, Hanani Farhah Harun, Nik Ruzni Nik Idris
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With the implied volatility as an important factor in financial decision-making, in particular in option pricing valuation, and also the given fact that the pricing biases of Leland option pricing models and the implied volatility structure for the options are related, this study considers examining the implied adjusted volatility smile patterns and term structures in the S&P/ASX 200 index options using the different Leland option pricing models. The examination of the implied adjusted volatility smiles and term structures in the Australian index options market covers the global financial crisis in the mid-2007. The implied adjusted volatility was found to escalate approximately triple the rate prior the crisis.Keywords: implied adjusted volatility, financial crisis, Leland option pricing models, Australian index options
Procedia PDF Downloads 3792 Identification of Factors Affecting Technical Efficiency Sugar Cane Farming in East Java
Authors: Noor Rizkiyah, Djoko Koestiono, Budi Setiawan, Nuhfil Hanani
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This research aims to identify the factors that affect the production of sugar cane, the level of technical efficiency of farming sugar cane ratooning and factors that affect technical inefficiency. Research carried out in Malang of East Java with sampling in a non random sampling stratified proportioned and obtained 172 household sugar cane farmers who are classified based on the level of ratooning i.e. ratooning I 3-4 times ratoning, ratooning II 5-10 times ratoning as well as ratooning III > 10 times ratoning. The method used is the Stochastic Production Frontier approach MLE (maximum likelihood estimation). From the results obtained by analysis of the factors affecting the production of sugar cane farming land, namely ratooning fertilizer use ZA petroganic, use of fertilizer and seeds of embroidery and labor. While the average level of sugar cane farmers ratooning efficiency of 0.78 and categorized yet efficient technically. For the factors that influence the technical inefficiency i.e. age, number of dependents and the frequency of family ratooning. Though not yet technically efficient but sugar cane farmers cultivate cultivation remains ratooning. But if it is done repeatedly ratooning will result in a decrease in the production of sugar cane. Whereas the results of the analysis of farming level of feasibility or RC ratooning sugar cane ratio of 1.15 so worth trying to accomplish. Thus with increased technology and combining the use of inputs is an attempt to let the technical efficiency can be achieved so that the more worthy to be organised.Keywords: technical efficiency, production, sugarcane, frontier
Procedia PDF Downloads 1731 The Difference of Serum Tnf-α Levels between Patients Schizophrenic Male with Smoking and Healthy Control
Authors: Rona Hanani Simamora, Bahagia Loebis, M. Surya Husada
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Background: The exact cause of schizophrenia is not known, although several etiology theories have been proposed for the disease, including immune dysfunction or autoimmune mechanisms. Cytokines including Tnf-α has an important role in the pathophysiology of schizophrenia and the effects of pharmacological treatment with antipsychotics. Nicotine is widespread effects on the brain, immune system and cytokine levels. Smoking among schizophrenic patients could play a role in the altered cytokine profiles of schizophrenia such as Tnf-α. Aims: To determine differences of serum Tnf-α levels between schizophrenic patients with smoking in male and healthy control. Methods: This study was a comparative analytic study, divided into two groups: 1) group of male schizophrenic patients with smoking (n1=30) with inclusion criteria were patients who have been diagnosed schizophrenic based PPDGJ-III, 20-60 years old, male, smoking, chronic schizophrenic patients in the stable phase and willing to participate this study. Exclusion criteria were having other mental disorders and comorbidity with other medical illnesses. 2) healthy control group (n2=30) with inclusion criteria were 20-60 years old, male, smoking, willing to participate this study. Exclusion criteria were having mental disorder, a family history of psychiatric disorders, the other medical illnesses, a history of alcohol and other substances abuse (except caffeine and nicotine). Serum Tnf-α were analyzed using the Quantikine HS Human Tnf –α Immunoassay. Results: Serum Tnf-α level measure in patient schizophrenia male with smoking and compared with the healthy control subjects. Tnf-α levels were significantly higher in patients schizophrenic male with smoking (25,79±27,96) to healthy control subjects (2,74±2,19), by using the Mann Whitney U test showed a statistically significant difference was observed for serum Tnf-α level (p < 0,001). Conclusions: Schizophrenia is a highly heterogeneous disorder, and this study shows an increase Tnf-α as pro-inflammation cytokines in schizophrenics. These results suggest an immune abnormalities may be involved in the etiology and pathophysiology of schizophrenia.Keywords: male, schizophrenic, smoking, Tnf Alpha
Procedia PDF Downloads 249