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Eddy-covariance carbon balance, photosynthetic capacity and vegetation indices in a harvested boreal jack pine standHawthorne, Iain 05 1900 (has links)
Eddy-covariance (EC) CO₂ flux data were analysed and annual carbon (C) balances estimated for a four-year period (2004-2007) following clearcut harvesting of a boreal jack pine stand in northern Saskatchewan. The site was a source of C to the atmosphere for all years, with annual net ecosystem productivity (NEP) increasing from -153 g C m⁻² yr⁻¹ in 2004 to -63 g C m⁻² yr⁻¹ in 2007. This increase was mainly due to gross primary productivity (GPP) increasing significantly from 78 to 200 g C m⁻² yr⁻¹ , while ecosystem respiration (R) increased only slightly from 231 to 263 g C m⁻² yr⁻¹ over the same period. In the 2006 growing season (GS), a field campaign was conducted to investigate the relationships between monthly destructive measurements of leaf area index (LAI) and daily measurements of the normalized difference vegetation index (NDVI) and photosynthetic capacity (Amax). The latter was derived from 5-day, 16-day, 30-day and annual Michaelis-Menten light response analyses using daytime measurements of NEP and incident photosynthetically active radiation. Digital-camera data were used to evaluate the potential of using the rectilinear-lens vegetation index (RLVI) as a surrogate for NDVI of a young forest stand. Results showed that LAI was linearly related to NDVI and RLVI, which was largely the result of changes in the deciduous vegetation component across the GS. These results indicate that RLVI could be used as a surrogate for NDVI up to a GS maximum LAI of 0.91 m2 m⁻² observed in 2006. Measured mean (± 1 S.D.) GS LAI was 0.67 (± 0.24) m² m⁻² in 2006. LAI accounted for the majority of the variability in Amax at the 30-day time scale, while at shorter time scales air temperature was the dominant control. For 2004 to 2007, mean spring estimates of LAI were 0.25, 0.29, 0.38 (compared to 0.40 m² m⁻² from measurements) and 0.41 m² m⁻², respectively. Results suggest that a steady increase in the jack pine LAI component accounted for the annual increases in GPP and hence NEP over the four years.
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Segregation and employment in Swedish regionsSaijeva, Heda January 2011 (has links)
Immigration to Sweden has increased since Second World War. The immigra-tion pattern has also shifted from labor immigration to refugee immigration. The relative labor market performance of immigrants began to worsen at the end of 1970s. The employment rate among foreign born persons is considera-bly lower than it is among Swedish born persons.Integration of foreign born persons in the areas of education, income and em-ployment varies among FA-regions in Sweden. FA-region means functional analysis region, where you can live and work without having time-wasting trips.The purpose of this thesis is to analyze the relationship between labor market participation of immigrants and segregation on the regional level.Three indices (Dissimilarity, Isolation and Gini) of segregation are used in or-der to investigate the relationship between segregation and employment level among immigrants. The results show that there exists a negative relationship between these variables. In FA-regions of metropolitan regions in spite of high segregation rate the relationship between segregation and employment rate is slightly weaker, than it is among FA-regions of large city regions. The main conclusion of this study is the regional perspective, the necessity of making this kind of analysis on regional level, not country level.
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Eddy-covariance carbon balance, photosynthetic capacity and vegetation indices in a harvested boreal jack pine standHawthorne, Iain 05 1900 (has links)
Eddy-covariance (EC) CO₂ flux data were analysed and annual carbon (C) balances estimated for a four-year period (2004-2007) following clearcut harvesting of a boreal jack pine stand in northern Saskatchewan. The site was a source of C to the atmosphere for all years, with annual net ecosystem productivity (NEP) increasing from -153 g C m⁻² yr⁻¹ in 2004 to -63 g C m⁻² yr⁻¹ in 2007. This increase was mainly due to gross primary productivity (GPP) increasing significantly from 78 to 200 g C m⁻² yr⁻¹ , while ecosystem respiration (R) increased only slightly from 231 to 263 g C m⁻² yr⁻¹ over the same period. In the 2006 growing season (GS), a field campaign was conducted to investigate the relationships between monthly destructive measurements of leaf area index (LAI) and daily measurements of the normalized difference vegetation index (NDVI) and photosynthetic capacity (Amax). The latter was derived from 5-day, 16-day, 30-day and annual Michaelis-Menten light response analyses using daytime measurements of NEP and incident photosynthetically active radiation. Digital-camera data were used to evaluate the potential of using the rectilinear-lens vegetation index (RLVI) as a surrogate for NDVI of a young forest stand. Results showed that LAI was linearly related to NDVI and RLVI, which was largely the result of changes in the deciduous vegetation component across the GS. These results indicate that RLVI could be used as a surrogate for NDVI up to a GS maximum LAI of 0.91 m2 m⁻² observed in 2006. Measured mean (± 1 S.D.) GS LAI was 0.67 (± 0.24) m² m⁻² in 2006. LAI accounted for the majority of the variability in Amax at the 30-day time scale, while at shorter time scales air temperature was the dominant control. For 2004 to 2007, mean spring estimates of LAI were 0.25, 0.29, 0.38 (compared to 0.40 m² m⁻² from measurements) and 0.41 m² m⁻², respectively. Results suggest that a steady increase in the jack pine LAI component accounted for the annual increases in GPP and hence NEP over the four years.
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Evaluating water quality and biotic indices in the Lower Little Bow River, AlbertaScott, Janet L Unknown Date
No description available.
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The Hang Seng Index options market in Hong Kong /Cheung, Yuk-lung, Alan. January 1994 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 107-109).
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Eddy-covariance carbon balance, photosynthetic capacity and vegetation indices in a harvested boreal jack pine standHawthorne, Iain 05 1900 (has links)
Eddy-covariance (EC) CO₂ flux data were analysed and annual carbon (C) balances estimated for a four-year period (2004-2007) following clearcut harvesting of a boreal jack pine stand in northern Saskatchewan. The site was a source of C to the atmosphere for all years, with annual net ecosystem productivity (NEP) increasing from -153 g C m⁻² yr⁻¹ in 2004 to -63 g C m⁻² yr⁻¹ in 2007. This increase was mainly due to gross primary productivity (GPP) increasing significantly from 78 to 200 g C m⁻² yr⁻¹ , while ecosystem respiration (R) increased only slightly from 231 to 263 g C m⁻² yr⁻¹ over the same period. In the 2006 growing season (GS), a field campaign was conducted to investigate the relationships between monthly destructive measurements of leaf area index (LAI) and daily measurements of the normalized difference vegetation index (NDVI) and photosynthetic capacity (Amax). The latter was derived from 5-day, 16-day, 30-day and annual Michaelis-Menten light response analyses using daytime measurements of NEP and incident photosynthetically active radiation. Digital-camera data were used to evaluate the potential of using the rectilinear-lens vegetation index (RLVI) as a surrogate for NDVI of a young forest stand. Results showed that LAI was linearly related to NDVI and RLVI, which was largely the result of changes in the deciduous vegetation component across the GS. These results indicate that RLVI could be used as a surrogate for NDVI up to a GS maximum LAI of 0.91 m2 m⁻² observed in 2006. Measured mean (± 1 S.D.) GS LAI was 0.67 (± 0.24) m² m⁻² in 2006. LAI accounted for the majority of the variability in Amax at the 30-day time scale, while at shorter time scales air temperature was the dominant control. For 2004 to 2007, mean spring estimates of LAI were 0.25, 0.29, 0.38 (compared to 0.40 m² m⁻² from measurements) and 0.41 m² m⁻², respectively. Results suggest that a steady increase in the jack pine LAI component accounted for the annual increases in GPP and hence NEP over the four years. / Land and Food Systems, Faculty of / Graduate
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The index reconstruction effect : An event study on the OMX Stockholm Benchmark IndexAskeljung, Love January 2021 (has links)
Background. Due to prevailing technological development, telecommunication and computers have become very advanced. This has had a tremendous effect on the financial markets as well, various facilitating financial means have become much more common. One of such is passively managed index funds which does not only use index as a benchmark but also trade the stocks in the index. Thus, guaranteeing the fund a return equal to the market return and to a lower cost than an equally good actively managed fund. Index funds have in recent times increased in popularity, which has left its mark. The price of the stocks included to and excluded from an index has been observed to respectively increase and decrease in value. Research on the price effects caused by index revision, or the effects that inclusion and exclusion have on the price of underlying shares, has been around since the 1980s. In the literature, it is generally accepted that inclusion to an index results in a positive price development, while exclusion results in a negative price development. However, the literature does not agree on whether the price effects are long-term or short-term. The disagreement began with the first studies in the field, where one author found that the price effects were long-lasting, even permanent. The others, on the other hand, found that the price effects were short-lived and returned to their original value when the trading ceased. Subsequent research is equally inconsistent. Some studies have found temporary changes, and some have found permanent ones. In this uncertainty, different theories of explanation have also been presented for the different outcomes, but these do not agree either. Objectives. To bring some clarity to the problems within the literature, the purpose of this study is to investigate the stock price effects from the reconstruction of a Swedish market index, with consideration of whether the effects are temporary or permanent. Methods. This study applied the event study methodology and the market model to examine the abnormal return found around the announcement day and the changing day. The study is based on 195 stocks that were included to and excluded from the OMX Stockholm Benchmark Index between the years 2009 and 2019. Results. This study did not find any statistically significant price change in the period before the announcement date. However, there were indications that the announcement day did have a positive effect on the included stocks and a negative effect on the excluded stocks. But the time after the announcement day and prior to the changing day did not show any statistically significant price changes. The changing day and the period after were both found to be negatively significant for inclusions. Thus, indicating a negative price effect on the day of inclusion and the period that followed. These results are consistent with previous studies that have found a price drop on the changing day and the following period. A further test of the relationship between the abnormal return found on the announcement day and the changing day revealed that the price increase was concentrated to the announcement day. A possible explanation for this outcome may be that index funds that trade on the Swedish exchange have recognized the opportunity to trade closer to the announcement day without incurring any losses and acted accordingly. Regarding the exclusions, the changing days were not found to be statistically significant. Neither did the period following the changing day show any statistical significance. This result could be due to a delayed reaction to the changing day, given that this group showed a slow reaction to the announcement day as well. Both the announcement day and the day after the announcement day were statistically significant at the 1% level. Other possible causes for the deviating results are errors in execution or data. Conclusions. The result of this study is consistent with other studies that find a temporary price reaction to the index reconstruction.
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Validation and optimization of the speech transmission index for the English languageMorales, Lorenzo January 2014 (has links)
No description available.
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Modulation Index and FM Improvement for Analog TVBaylor, J. Thomas 11 1900 (has links)
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The concepts of modulation index and FM improvement are simple and straightforward when the modulating signals are sinesoidal. For a complex baseband waveform such as analog TV, the FM improvement may be seriously underestimated.
A method for computer simulation of video waveforms and the resulting spectra are presented.
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Daily House Price Indexes: Volatility Dynamics and Longer-Run PredictionsWang, Wenjing January 2014 (has links)
<p>This dissertation presents the construction procedure of “high-frequency” daily measure of changes in housing valuations, and analyzes its return dynamics, as well as investigates its relationship to capital markets. The dissertation consists of three chapters. The first chapter introduces the house price index methodologies and housing transaction data, and reviews the related literature. The second chapter shows the construction and modeling of daily house price indexes and highlights the informational advantage of the daily indexes. The final chapter provides detailed empirical and theoretical investigations of housing index return volatilities. </p><p>Chapter 2 discusses the relationship of the housing market with the other markets, such as consumer good market and financial markets. Different housing price indexes and their construction methodologies are introduced, with emphases on the repeat sales model and S&P/Case Shiller Home Price Index. A detailed description of the housing transaction data I use in the dissertation is also provided in this chapter.</p><p>Chapter 3 is co-authored with Professor Tim Bollerslev and Professor Andrew Patton. We construct daily house price indexes for ten major U.S. metropolitan areas. Our calculations are based on a comprehensive database of several million residential property transactions and a standard repeat-sales method that closely mimics the procedure used in the construction of the popular monthly Case-Shiller house price indexes. Our new daily house price indexes exhibit dynamic features similar to those of other daily asset prices, with mild autocorrelation and strong conditional heteroskedasticity. The correlations across house price index returns are low at the daily frequency, but rise monotonically with the return horizon, and are commensurate with existing empirical evidence for existing monthly and quarterly house price series. Timely and accurate measures of house prices are important in a variety of applications, and are particularly valuable during times of turbulence, such as the recent housing crisis. To quantify the informational advantage of our daily index, we show that a relatively simple multivariate time series model for the daily house price index returns, explicitly allowing for commonalities across cities and GARCH effects, produces forecasts of monthly house price changes that are superior to various alternative forecast procedures based on lower frequency data.</p><p>Chapter 4 investigates the properties of housing index return volatilities. Similar to stock market volatility, housing volatilities are found to respond asymmetrically to negative and positive returns. A direct test of volatility on changes in loan-to-value ratio suggests that the observed volatility asymmetry does not stem from changes in degree of housing financial leverage, but could result from the risk premium carried by housing volatility, which is supported by a consumption-based asset pricing model with housing. Moreover, housing and stock volatilities are found to be positively correlated from a set of predictive regressions based on realized variances of housing and stock markets, in which higher (lower) volatility in one market will be followed by higher (lower) volatility in the other. Finally, housing and stock cross-sectional return dispersions are shown to contain useful information in predicting both within-market and cross-market realized volatilities.</p> / Dissertation
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