412 research outputs found

    The cleaning of burned and contaminated archaeological maize prior to 87Sr/86Sr analysis

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    Accurate trace-metal and strontium-isotope analyses of archaeological corn cobs require that metal contaminants be removed prior to chemical analysis. Archaeological cobs are often coated with construction debris, dust, or soilwhich contains mineral particles. In addition, most archaeological cobs are partially or completely burned and the burned parts incorporate mineral debris in their hardened residual structures. Unburned cobs are weak ion exchangers and most metals within a cob are not firmly bound to cob organic matter; therefore, immersing cobs in acids and rinsing them in deionized water to remove mineral contaminants may result in the undesirable loss of metals, including strontium, from the cob. In this paper we show that some cob metal-pair ratios are not substantially changed when the cob is ‘‘cleaned’’ with deionized water, if the water-cob contact time does not exceed five minutes. Additionally, we introduce a method for eliminating mineral contaminants in both burned and unburned cobs, thus rendering them acceptable for strontium-isotope analysis. However, the decontamination procedure results in the rapid non-stoichiometric leaching of trace metals from the unburned cobs and it is possible that most metals will be extracted from the cobs during the lengthy decontamination process. Trace metals, in particular Al and Ca, should be analyzed in order to determine the presence and level of mineral contamination after cleaning

    Carbon Pricing in Climate Policy: Seven Reasons, Complementary Instruments, and Political Economy Considerations

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    Carbon pricing is a recurrent theme in debates on climate policy. Discarded at the 2009 COP in Copenhagen, it remained part of deliberations for a climate agreement in subsequent years. As there is still much misunderstanding about the many reasons to implement a global carbon price, ideological resistance against it prospers. Here, we present the main arguments for carbon pricing, to stimulate a fair and well-informed discussion about it. These include considerations that have received little attention so far. We stress that a main reason to use carbon pricing is environmental effectiveness at a relatively low cost, which in turn contributes to enhance social and political acceptability of climate policy. This includes the property that corrected prices stimulate rapid environmental innovations. These arguments are underappreciated in the public debate, where pricing is frequently downplayed and the erroneous view that innovation policies are sufficient is widespread. Carbon pricing and technology policies are, though, largely complementary and thus are both needed for effective climate policy. We also comment on the complementarity of other instruments to carbon pricing. We further discuss distributional consequences of carbon pricing and present suggestions on how to address these. Other political economy issues that receive attention are lobbying, co-benefits, international policy coordination, motivational crowding in/out, and long-term commitment. The overview ends with reflections on implementing a global carbon price, whether through a carbon tax or emissions trading. The discussion goes beyond traditional arguments from environmental economics by including relevant insights from energy research and innovation studies as well

    Liberalizing trade in environmental goods and services

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    We examine the effects of trade liberalization in environmental goods in a model with one domestic downstream polluting firm and two upstream firms (one domestic, one foreign). The upstream firms offer their technologies to the downstream firm at a flat fee. The domestic government sets the emission tax rate after the outcome of R&D is known. The effect of liberalization on the domestic upstream firm's R&D incentive is ambiguous. Liberalization usually results in cleaner production, which allows the country to reach higher welfare. However this increase in welfare is typically achieved at the expense of the environment (a backfire effect)

    An extreme firm-specific news sentiment asymmetry based trading strategy

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    News sentiment has been empirically observed to have impact on financial market returns. In this study, we investigate firm-specific news from the Thomson Reuters News Analytics data from 2003 to 2014 and propose an optimal trading strategy based on a sentiment shock score and a sentiment trend score which measure extreme positive and negative sentiment levels for individual stocks. The intuition behind this approach is that the impact of events that generate extreme investor sentiment changes tends to have long and lasting effects to market movement and hence provides better prediction to market returns. We document that there exists an optimal signal region for both indicators. And we also show extreme positive sentiment provides better a signal than extreme negative sentiment, which presents an asymmetric market behavior in terms of news sentiment impact. The back test results show that extreme positive sentiment generates robust and superior trading signals in all market conditions, and its risk-adjusted returns significantly outperform the S&P 500 index over the same time period

    PERENCANAAN FDD-LTE MENGGUNAKAN FREKUENSI 1800MHZ PADA PERANCANGAN INDOOR BUILDING COVERAGE DI YOGYA KEPATIHAN BANDUNG

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    Material sebuah gedung merupakan salah satu penyebab dari terjadinya fading sehingga menghambat sinyal masuk ke dalam gedung yang mengakibatkan sinyal didalam gedung tersebut lemah. Pada gedung Yogya Kepatihan memiliki masalah terhadap kualitas jaringan didalamnya sehingga butuh dilakukannya perencanaan Indoor untuk mengatasi masalah tersebut. Berdasarkan hasil analisis dilakukannya walk test diperoleh nilai rata-rata dari RSRP sebesar -96 dBm dan SINR sebesar 8 dB, sedangkan drivetest sekitaran Gedung memperoleh hasil RSRP sebesar -72 dBm dan SINR sebesar 5 dB. Penerapan Indoor Building Coverage (IBC) ini menggunakan sistem Distributed Antenna System (DAS) dengan teknik FDD-LTE pita frekuensi 1800 MHz, untuk simulasinya menggunakan Radiowave Propagation Software (RPS) dengan model propagasi Cost-231 Multi-Wall Indoor. Operator Telkomsel menjadi kasus dalam penerapan ini. Walktest di dalam gedung menggunakan Nemo handy, sedangkan drivetest menggunakan GnetTrack Pro. Setelah mendapatkan data lalu dilanjutkan perhitungan capacity planning dan coverage planning sehingga mendapatkan perhitungan untuk jumlah antena yang akan di simulasikan ke dalam software RPS untuk mendapatkan hasil parameter yang sesuai dengan standar Key Performance Indicator (KPI) Operator Telkomsel yaitu RSRP > -85 dBm dan SINR > 10 dB. Dari hasil simulasi ini, diperoleh peningkatan nilai rata-rata RSRP > -76 dBm sebanyak 81,95% dan rata-rata nilai SINR > 26 sebanyak 71,56%. Kata Kunci: LTE, FDD, IBC, DAS, RPS

    The humanistic roots of Islamic administration and leadership for education : philosophical foundations for cross-cultural and transcultural teaching

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    For a number of decades, a humanistic approach has been a minor but persistent one in the Western field of administrative and leadership studies, and only recently has been broadening to include other humanist traditions (Dierksmeier et al., 2011) and has yet to be fully explored in educational administration and its pedagogy and curriculum although some foundational work has been done (e.g., Samier, 2005). The focus in this chapter is on the Islamic humanist tradition as it relates to the teaching of educational administration and leadership in a Muslim context, with implications for cross-cultural and transcultural use. The second purpose of the chapter is to show the correspondences that exist between the Islamic and Western humanist traditions in terms of human values, knowledge and educational ideal, which in this chapter are argued to be close to the Western Idealist tradition and the German Bildung conception of education as well as the strong interpretive and hermeneutic foundations that originated in the Islamic tradition and which influenced the foundations of many relevant European schools of thought, particularly in the Enlightenment.The initial section of the chapter is a comparative examination of the central principles of the Islamic humanist tradition from the classical through to contemporary times with the Western humanist tradition as they relate to conceptions of the good, ethics, the construction of meaning and a set of higher order values predicated upon human dignity, integrity, empathy, well-being, and the public good (Goodman, 2003) covering a number of important scholars like Al Farabi, al Isfanhani, and Edward Said (e.g., Kraemer, 1986). In both, professions are viewed as meaningful work that allow for large measures of decision making, and are grounded in human qualities and needs including autonomy, freedom and emancipation balanced with responsibilities, obligations and duties to society. These are compared with the corresponding principles of knowledge in Western humanism which includes a strong constructivist view of reality (Makdisi, 1990). Secondly, the chapter examines the principles of good or ideal leadership and administration that humanism aims at in its preparation of officials, including those in the educational sector in both the classical Islamic tradition (Hassi, 2012) and Western approaches to humanistic administration and leadership (Czarniawska-Joerges & Guillet de Monthoux, 1994; Gagliardi & Czarniawska, 2006; Leoussi, 2000). The third section focusses on close correspondences that exist between the Islamic (Afsaruddin, 2016; al-Attas, 1980; Yasin & Jani, 2013) and Western (Aloni, 2007; Veugelers, 2011) humanist education traditions in terms of educational ideal as well as the kind of teaching practices that distinguish these traditions (Daiber, 2013; Dossett, 2014) as they apply to educational administration and leadership (Greenfield & Ribbins, 1993). The chapter concludes with a discussion of how the Islamic humanist tradition can contribute to cross-cultural and transcultural graduate teaching in international educational administration (Khan & Amann, 2013)

    Interactions Between Climate and Trade Policies: A Survey

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