Search results for "417"
showing 10 items of 46 documents
Long-term decrease in Asian monsoon rainfall and abrupt climate change events over the past 6,700 years
2021
Significance The variability of the Asian summer monsoon (ASM) is important for the functioning of ecological and societal systems at regional to continental scales, but the long-term evolution and interannual variability of this system is not well understood. Here, we present a stable isotope–based reconstruction of ASM variability covering 4680 BCE to 2011 CE. Superimposed on a gradual drying trend, a rapid drop in mean annual precipitation (>40%) toward persistently drier conditions occurred in ∼1675 BCE. This megadrought caused regional forest deterioration and enhanced aeolian activity affecting Chinese ecosystems. We argue that this abrupt aridification starting ∼2000 BCE triggered wa…
Assessing the profitability of investment projects using ordered fuzzy numbers
2019
Background: This article is motivated by the fact that most approaches to capital budgeting are deterministic. In reality, the capital budgeting problem is accompanied by the uncertainty and risk associated with dealing with imprecise data. Taking this uncertainty into account when performing analyses and calculations not only helps to better measure the profitability of investment projects, but also to expand the applicability of capital budgeting methods under real-life or uncertain conditions. The major contribution of this paper is the development of a novel approach to assessing the profitability of an investment project in the presence of uncertainty. Methods: We present a novel appro…
Use of HFC fluids as suitable replacements in low-temperature refrigeration plants
2014
An experimental investigation of the performance of a low-temperature refrigerating unit working with R22 and a comparison of its performance when operating with replacement HFC fluids in accordance with the European Regulation CE-1005/2009 are presented in this paper. Plant working efficiency was tested with R22, as baseline, and then compared with four different HFC fluids: R413A, R417A, R422A and R422D. The refrigerating unit was a vapour-compression plant equipped with a reciprocating double-cylinder compressor able to keep the cold room at -20ºC. Lower values of the temperature at the end of compression and polytrophic exponent can be achieved with the HFC tested. Substituting the R22 …
The Black-Litterman model
2013
Masteroppgave i økonomi og administrasjon - Universitetet i Agder 2013 The Markowitz model has two problematic tendencies; unintuitive portfolios and portfolios with high transaction costs. The Black-Litterman model was made as an improvement of the Markowitz model. It uses a Bayesian approach to combine the views of the investor with the equilibrium portfolio. The main purpose of the model is to create intuitive portfolios and limit the transaction costs. With the computer power available today, the implementation of mathematical models are an important issue. Using the programming language R, I will in this thesis look at possible ways of implementing the Black-Litterman model. Todays inv…
Arendt y Heidegger ante el 'diluvio de Auschwitz'
2019
Tras las Conferencias de Bremen de Martin Heidegger y, más aún, tras los escritos de Hannah Arendt, el nacionalsocialismo ha sido reinterpretado como revelador de la modernidad técnica hasta el punto de que la institución nazi de los campos de concentración y exterminio se ha visto erigida en paradigma de esta modernidad. Esta visión, que podría llamarse posmoderna, de la historia del siglo xx merece ser cuestionada.1 ¿Cómo es posible que la obra de Heidegger, ese profesor y rector nacionalsocialista a quien se le prohíbe enseñar en 1945, haya tardado tanto tiempo en ser reconocida como un caso ejemplar, dentro del campo filosófico, de la visión del mundo o Weltanschauung nacionalsocialista…
Multitemporal Unmixing of Medium-Spatial-Resolution Satellite Images: A Case Study Using MERIS Images for Land-Cover Mapping
2011
Data from current medium-spatial-resolution imaging spectroradiometers are used for land-cover mapping and land-cover change detection at regional to global scales. However, few landscapes are homogeneous at these scales, and this creates the so-called mixed-pixel problem. In this context, this study explores the use of the linear spectral mixture model to extract subpixel land-cover composition from medium-spatial-resolution data. In particular, a time series of MEdium Resolution Imaging Spectrometer (MERIS) full-resolution (FR; pixel size of 300 m) images acquired over The Netherlands is used to illustrate this study. The Netherlands was selected because of the following: 1) the fragmenta…
Virtualization of work in global supply chains
2016
Background: The paper is devoted to the notion and benefits of implementing virtual work in global supply chains. Virtual work must be understood as an intentional activity of a human being, aimed at rendering services (tangible and intangible), by means of ITC tools, performed in a distance from the traditional place of work, in a mobile manner. The empirical research were conducted on the basis of 4 case studies of global leaders of supply chains, which in accordance with M. Fisher's classification, represent two types. The case studies confirmed the positive influence of virtual work both in effective and flexible supply chains. Favourable market and technological conditions and incr…
The location of an international logistics center in Poland as a part of The One Belt One Road Initiative
2019
Background: The One Belt One Road initiative opens up many development opportunities for Central and Eastern European countries, some related to the possible construction of a logistics center in this area. For Poland, such an investment would also bring many benefits, not only due to infrastructure development, but also through acceleration of economic growth and job creation. In this context, the crucial issue becomes, what should be the role of an international logistics center and where should it be located. Due to the novelty of the subject, there is a shortcoming of scientific papers related to this issue. The scientific goal of the present paper is to fulfill the gap and to address …
The performance of Value-at-Risk models on the OBX index
2013
Masteroppgave i økonomi og administrasjon - Universitetet i Agder 2013 The measuring of risk has become one of the main fields in finance during the last two decades. Value-at-Risk (VaR) has become one of the most important risk measures and is widely used for numerous applications. This thesis compares different approaches to VaR based on traditional methods such as Historical Simulation, Moving Average and Exponentially Weighted Moving Average as well as advanced approaches based on GARCH models. Comparison is done on the OBX index return data, which is the main benchmark index on the Oslo Stock Exchange. The performance of the different VaR models is evaluated with out of sample backtest…
Buying Intentions Influenced by Various Determinants in Tourism
2014
Marketing has acquired a central role in tourism because it helps organizations to create value in transactions with buyers. Thus, this important area of any business process is used to educate consumers, to add value to their experience in tourism, and to seek new ways to reward loyalty through innovative schemes (e.g., programs for frequent travelers). This paper presents the examination of the responses of 154 tourists in relation to their intention to purchase a travel package and the factors that are usually decisive in the decision making process regarding tourism services, factors that could also create the loyalty that any tourism enterprise can create through marketing.