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Modelling surface runoff and soil erosion for Yen Bai Province, Vietnam, using the Soil and Water Assessment Tool (SWAT) / Mô Hình Hóa Nước Chảy Mặt và Xói Mòn Đất cho Tỉnh Yên Bái, Việt Nam Sử Dụng Mô Hình SWATNguyen, Hong Quang, Le, Thi Thu Hang, Pham, Thi Thanh Nga, Kappas, Martin 24 August 2017 (has links) (PDF)
Applications of the Soil and Water Assessment Tool (SWAT) are common. However, few attempts have focused on the tropics like in the Yen Bai province, Vietnam. Annual water-induced soil erosion (WSE) rates and surface runoff (SR) were estimated. The Nam Kim and Ngoi Hut watersheds were calibrated with accepted agreement between simulated and observed discharge. Correlations between precipitation, land covers, surface runoff and WSE were indicated. Although the estimated average WSE 4.1 t ha−1 year−1 (t ha−1 y−1) was moderate, some steep-bare areas were suffering serious soil loss of 26 t ha−1 y−1 and 15% of the province was calculated at the rate of 8.5 t ha−1 y−1. We found that the changes in WSE significantly correlated with land use changes. As calibrated SR matched closely with the measured data, we recommend SWAT applications for long-term soil erosion assessments in the tropics. / Những ứng dụng của mô hình công cụ đánh giá đất và nước (SWAT) đã được sử dụng phổ biến. Tuy nhiên có rất ít nghiên cứu tập trung vào khu vực nhiệt đới như tỉnh Yên Bái của Việt Nam. Trong nghiên cứu này, giá trị trung bình năm (2001-2012) nước chảy bề mặt (NCM) và xói mòn đất do nước (XM) đã được đánh giá trên cơ sở mô hình SWAT. Các thông số thủy văn của hai lưu vực sông là Nậm Kim và Ngòi Hút được tính toán và kiểm nghiệm với sự trùng hợp tương đối tốt giữa kết quả mô hình và số liệu thực đo. Mối liên hệ giữa lượng mưa, phủ bề mặt, NCM và XM cũng được phân tích và trình bầy chi tiết. Mặc dù giá trị XM năm được ước lượng ở mức trung bình cho toàn Tỉnh (4,1 tấn/ha/năm) nhưng ở một số khu vực nơi có độ dốc lớn và phủ mặt ít lại có lượng XM năm ở mức cao, 26 tấn/ha/năm và 15% tổng diện tích của Tỉnh có giá trị XM là 8,5 tấn/ha/năn. Kết quả nghiên cứu cho thấy sự liên hệ mật thiết giữa sự thay đổi phủ mặt tới giá trị XM. Trên cơ sở kết quả kiểm nghiệm mô hình khả quan, chúng tôi đề xuất sử dụng mô hình SWAT để đánh giá XM trong thời gian dài cho vùng nhiệt đới.
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Modelling surface runoff and soil erosion for Yen Bai Province, Vietnam, using the Soil and Water Assessment Tool (SWAT): Research articleNguyen, Hong Quang, Le, Thi Thu Hang, Pham, Thi Thanh Nga, Kappas, Martin 24 August 2017 (has links)
Applications of the Soil and Water Assessment Tool (SWAT) are common. However, few attempts have focused on the tropics like in the Yen Bai province, Vietnam. Annual water-induced soil erosion (WSE) rates and surface runoff (SR) were estimated. The Nam Kim and Ngoi Hut watersheds were calibrated with accepted agreement between simulated and observed discharge. Correlations between precipitation, land covers, surface runoff and WSE were indicated. Although the estimated average WSE 4.1 t ha−1 year−1 (t ha−1 y−1) was moderate, some steep-bare areas were suffering serious soil loss of 26 t ha−1 y−1 and 15% of the province was calculated at the rate of 8.5 t ha−1 y−1. We found that the changes in WSE significantly correlated with land use changes. As calibrated SR matched closely with the measured data, we recommend SWAT applications for long-term soil erosion assessments in the tropics. / Những ứng dụng của mô hình công cụ đánh giá đất và nước (SWAT) đã được sử dụng phổ biến. Tuy nhiên có rất ít nghiên cứu tập trung vào khu vực nhiệt đới như tỉnh Yên Bái của Việt Nam. Trong nghiên cứu này, giá trị trung bình năm (2001-2012) nước chảy bề mặt (NCM) và xói mòn đất do nước (XM) đã được đánh giá trên cơ sở mô hình SWAT. Các thông số thủy văn của hai lưu vực sông là Nậm Kim và Ngòi Hút được tính toán và kiểm nghiệm với sự trùng hợp tương đối tốt giữa kết quả mô hình và số liệu thực đo. Mối liên hệ giữa lượng mưa, phủ bề mặt, NCM và XM cũng được phân tích và trình bầy chi tiết. Mặc dù giá trị XM năm được ước lượng ở mức trung bình cho toàn Tỉnh (4,1 tấn/ha/năm) nhưng ở một số khu vực nơi có độ dốc lớn và phủ mặt ít lại có lượng XM năm ở mức cao, 26 tấn/ha/năm và 15% tổng diện tích của Tỉnh có giá trị XM là 8,5 tấn/ha/năn. Kết quả nghiên cứu cho thấy sự liên hệ mật thiết giữa sự thay đổi phủ mặt tới giá trị XM. Trên cơ sở kết quả kiểm nghiệm mô hình khả quan, chúng tôi đề xuất sử dụng mô hình SWAT để đánh giá XM trong thời gian dài cho vùng nhiệt đới.
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Modelling Soil Erosion, Flash Flood Prediction and Evapotranspiration in Northern VietnamNguyen, Hong Quang 17 February 2016 (has links)
No description available.
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Choosing a data frequency to forecast the quarterly yen-dollar exchange rateCann, Benjamin 03 October 2016 (has links)
Potentially valuable information about the underlying data generating process of a dependent variable is often lost when an independent variable is transformed to fit into the same sampling frequency as a dependent variable. With the mixed data sampling (MIDAS) technique and increasingly available data at high frequencies, the issue of choosing an optimal sampling frequency becomes apparent. We use financial data and the MIDAS technique to estimate thousands of regressions and forecasts in the quarterly, monthly, weekly, and daily sampling frequencies. Model fit and forecast performance measurements are calculated from each estimation and used to generate summary statistics for each sampling frequency so that comparisons can be made between frequencies. Our regression models contain an autoregressive component and five additional independent variables and are estimated with varying lag length specifications that incrementally increase up to five years of lags. Each regression is used to forecast a rolling, one and two-step ahead, static forecast of the quarterly Yen and U.S Dollar spot exchange rate. Our results suggest that it may be favourable to include high frequency variables for closer modeling of the underlying data generating process but not necessarily for increased forecasting performance. / Graduate / 0501 / 0508 / 0511 / benjamincann@gmail.com
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Carry Trading & Uncovered Interest Rate Parity : An overview and empirical study of its applicationsTafazoli, Farid, Westman, Mathias January 2011 (has links)
The thesis examine if the uncovered interest rate parity holds over a 10 year period between Japan and Australia/Norway/USA. The data is collected between February 2001 - December 2010 and is used to, through regression and correlation analysis, explain if the theory holds or not. In the thesis it is also included a simulated portfolio that shows how a carry trading strategy could have been exercised and proof is shown that you can indeed profit as an investor on this kind of trades with low risk. The thesis shows in the end that the theory of uncovered interest rate parity does not hold in the long term and that some opportunities for profits with low risk do exist. / Uppsatsen undersöker om det icke kurssäkrade ränteparitetsvilkoret har hållit på en 10-års period mellan Japan och Australien/Norge/USA. Månadsdata från februari 2001 till december 2010 används för att genom regressionsanalys samt undersökning av korrelationer se om sambandet håller eller inte. I studien finns också en simulerad portfölj som visar hur en carry trading portfölj kan ha sett ut under den undersökta tidsperioden och hur man kan profitera på denna typ av handel med låg risk. Studien visar i slutet att teorin om det kursosäkrade ränteparitetsvilkoret inte håller i det långa loppet och att vissa möjligheter till vinst existerar.
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A Case Study of Tzu-Chi Foundation As a Logic of Collective Action ProblemTu, Jan-Ping 22 August 2003 (has links)
Mancur Olson states that individual, after reasonable evaluation, takes the action of free ride. The main factor of free ride lies in the goal of collective actions --- collective goods. And the non-excludability in collective goods enables consumers to benefit without sharing costs.
Based on the framework of Olson¡¦s and Russell Hardin¡¦s theories of reaching the goal of collective actions, along with the theory of political entrepreneurs, this study surveys the collective actions of Tzu-Chi Foundation, in hope of depicting its factors and strategies for overcoming difficulties in collective actions.
This study gives an analysis of Tzu-Chi Foundation in terms of collective actions, concluding that its selective incentives are Master Cheng Yen¡¦s unconditional love, cause & effect cycle and pursuit of pop culture.
Successful marketing and computerized fund-raise tactics make people more willing to invest time and money in promoting Tzu-Chi Foundation. Few entrepreneurs are willing to bear the costs even without cooperation from other members, as they are satisfied with the collective goods provided by the group, just as Hardin states.
Furthermore, one of the solutions to collective actions of free ride is to rely on organization operating by political entrepreneurs. Master Cheng Yen successfully plays the role of entrepreneur leader, adopting strategies like keeping equidistance from each political party, developing constant sense of mission within the organization, exercising mild leadership and management strategies, consolidating the Foundation with religious prospect, recruiting elites and making good use of talents...etc. Multiplied by her female leader impact on Taiwan, these factors combined are the key points of Tzu-Chi Foundation¡¦s success.
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Survey on heavy metals contaminated soils in Thai Nguyen and Hung Yen provinces in Northern Vietnam: Research ArticleChu, Thi Thu Ha 07 August 2012 (has links)
In Vietnam, soil contamination with lead and cadmium at very high level was investigated anddiscovered in the surrounding areas of zinc-lead mining and processing factory in Tan Long (Dong Hy district, Thai Nguyen province) and around the lead-recycling smelter in Chi Dao (Van Lam district, Hung Yen province). The survey on soil contaminated by arsenic due to the tin mining and sifting activities in Ha Thuong (Dai Tu district, Thai Nguyen province) was also carried out. In Tan Long, the concentrations of lead and cadmium in the old solid waste dump from zinc-lead factory varied from 1,100 to 13,000 mg·kg-1, and from 11.34 to 61.04 mg·kg-1, respectively. Soil Pollution Indexes (SPI) of lead and cadmium were highest in the old solid waste dump area, followed by the ones in the rice paddy soils. In Chi Dao, the soils of many sites were polluted with lead and cadmium such as in the gardens of lead-recycling households where the concentrations of lead and cadmium were 7,000 - 15,000 mg·kg-1 and 1.8 - 3.6 mg·kg-1. In rice paddies, the soils were also polluted by lead. SPI of lead in paddy soil areas within 300 m radius from the lead smelter were from 3.6 to 100 fold higher than the safe limit. The sediment from the ditch near the lead smelters contained extremely high levels of lead (7,000 - 110,000 mg·kg-1) and cadmium (3.8 - 17.7 mg·kg-1). The tin mining and sifting activities in Ha Thuong was the cause for the arsenic contamination of the soil in this area. The arsenic contents in soils at all locations investigated were higher than 320 mg·kg-1 (dry weight) and up to 3,809 mg·kg-1. / Tại Việt Nam, đất bị ô nhiễm bởi chì và ca-đi-mi với hàm lượng cao đã được điều tra phát hiện ở các khu vực phụ cận của nhà máy khai thác và chế biến kẽm/chì thuộc địa phận xã Tân Long, huyện Đồng Hỷ, tỉnh Thái Nguyên và các khu vực phụ cận của lò tái chế chì thuộc địa phận xã Chỉ Đạo, huyện Văn Lâm, tỉnh Hưng Yên. Sự khảo sát đất bị ô nhiễm bởi a-sen do các hoạt động khai thác và tuyển thiếc ở xã Hà Thượng, huyện Đại Từ, tỉnh Thái Nguyên cũng đã được tiến hành. Tại xã Tân Long, nồng độ chì và ca-đi-mi trong bãi chất thải rắn cũ từ nhà máy sản xuất kẽm chì là 1.100 - 1.300 mg.kg-1 và từ 11,34 đến 61,04 mg.kg-1, tương ứng. Chỉ số ô nhiễm đất (SPI) của chì và ca-đi-mi cao nhất trong khu vực đổ chất thải rắn cũ, tiếp theo sau là ở các ruộng lúa. Tại xã Chỉ Đạo, đất ở nhiều địa điểm đã bị ô nhiễm chì và ca-đi-mi chẳng hạn như trong khu vườn của các hộ gia đình tái chế chì, nồng độ chì và ca-đi-mi là 7.000 - 15.000 mg.kg-1 và 1,8 - 3,6 mg.kg-1. Trong cánh đồng lúa, đất cũng bị ô nhiễm bởi chì. Chỉ số ô nhiễm đất của chì (SPI-Pb) trong cánh đồng lúa trong vòng bán kính 300 m từ lò tái chế chì cao hơn giới hạn của đất an toàn từ 3,6 đến 100 lần. Trầm tích thu từ kênh gần lò tái chế chì chứa hàm lượng chì rất cao (.7000 - 110.000 mg.kg-1) và ca-đi-mi (3,8 - 17,7 mg.kg-1). Việc khai thác và tuyển thiếc tại xã Hà Thượng đã gây ra ô nhiễm a-sen trong đất tại khu vực này. Hàm lượng a-sen trong đất tại tất cả các địa điểm nghiên cứu cao hơn 320 mg.kg-1 (trọng lượng khô), đặc biệt là lên đến 3809 mg.kg-1.
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Essays in exchange rates and international financeMenla Ali, Faek January 2014 (has links)
This thesis is based on four essays in exchange rates and international finance. The first essay, examined in the second chapter, considers the long-run performance of the flexible-price monetary model as well as the real interest differential monetary model to explain the dollar–yen exchange rate during a period of high international capital mobility. We apply the Johansen methodology to quarterly data over the period 1980:01–2009:04 and show that the inadequacy of the two monetary models is due to the breakdown of their underlying building-blocks, money demand stability and purchasing power parity. In particular, modifying the monetary models by adjusting them for real stock prices to capture the stability of money demands on one hand and also for real economic variables such as productivity differential, relative government spending, and real oil price to explain the persistence in the real exchange rate on the other provide long-run relationships that appear consistent with the monetary models. Our findings of long-run weak exogeneity tests also emphasise the importance of the extended models employed here. The second essay, examined in the third chapter, is on the nature of the linkages between stock market prices and exchange rates in six advanced economies, namely the US, the UK, Canada, Japan, the euro area, and Switzerland, using data on the banking crisis between 2007 and 2010. Bivariate GARCH-BEKK models are estimated to produce evidence of unidirectional Granger causality from stock returns to exchange rate changes in the US and the UK, in the opposite direction in Canada, and of bidirectional causality in the euro area and Switzerland. Furthermore, causality-in-variance from stock returns to exchange rate changes is found in Japan and in the opposite direction in the euro area and Switzerland, whilst there is evidence of bidirectional causality-in-variance in the US and Canada. These findings imply limited opportunities for investors to diversify their assets during this period. The third essay, examined in the fourth chapter, considers the impact of net bond and net equity portfolio flows on exchange rate changes. Two-state Markov-switching models are estimated for the exchange rate of the US vis-a-vis Canada, the euro area, Japan and the UK. Our results suggest that the relationship between net portfolio flows and exchange rate changes is nonlinear for all cases considered, except that of the US dollar against the Canadian dollar. The fourth essay, examined in the fifth chapter, considers the impact of exchange rate uncertainty on different components of net portfolio flows, namely net equity and net bond flows, as well as the dynamic linkages between exchange rate volatility and the variability of these two types of flows. Specifically, a bivariate GARCH-BEKK-in mean model is estimated using bilateral data for the US vis-à-vis Australia, the UK, Japan, Canada, the euro area, and Sweden over the period 1988:01-2011:12. The results indicate that the effect of exchange rate uncertainty on net equity flows is negative in the euro area, the UK and Sweden, and positive in Australia, whilst two countries (Canada and Japan) showed insignificant responses. With regard to the impact of uncertainty on net bond flows, it is shown to be negative in all countries, except Canada (where it is positive). Under the assumption of risk aversion, this suggests that exchange rate uncertainty induces investors, especially those of the counterpart countries to the US, to reduce their financing activities to maximise returns and minimise exposure to uncertainty. This evidence is strong for the UK, the euro area and Sweden as opposed to Canada, Australia and Japan. Furthermore, since exchange rate volatility and the variability of flows are interlinked, exchange rate or credit controls on these flows can be used to pursue economic and financial stability.
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Darwinism's applications in modern Chinese writingsChou, Hsiu-Feng January 2014 (has links)
The core aim of this interdisciplinary research is to provide a critical analysis of the influence of Darwinism and Social Darwinism on a sample of modern Chinese writings. To achieve these aims, the researcher uses a range of both Chinese and English sources to explore their close affinities with Darwinism and Social Darwinism. Following this course, the research examines how Darwinian thought was introduced to the Chinese reading public in the late nineteenth century through a translation of Thomas Henry Huxley’s Evolution and Ethics by Yen Fu, and the subsequent impact of this work and Darwinian thought in general on seven literary and political figures: K'ang Yu-wei, Liang Qichao, Lu Xun, Hu Shih, Chen Duxiu, Sun Yat-sen and Mao Zedong. From an historical perspective, the Opium Wars and imperial invasions of China in the nineteenth century severely weakened the country’s political, economic, diplomatic, military, educational and cultural power. For these reasons and others, from 1840 to 1949, China experienced a tumultuous period of social and political transformation, which has eventually led to her revival in the twenty-first century. It will be seen that each of the literary figures examined here used evolutionary thought to justify revolution at various points on China’s long march to modernity. Progressive Darwinian ideas sharply contrasted with the old Confucian values upheld within Chinese communities. Nevertheless, the faults and weaknesses of Qing China awakened many pioneering revolutionaries who sought to reverse the status quo by initiating a series of radical reforms and revolutionary movements. Many within the Chinese intellectual elite looked to the tide of change and progress coming from the West, which they hoped might replace the recent historical stagnation and Confucian dogma embedded in Chinese culture and society. In this vein, many of these pioneering revolutionaries set about driving the historical transformation of China by selecting, translating and interpreting Darwinian ideas in their own writings. From Yen Fu in the nineteenth century to Mao Zedong in the twentieth century, evolutionary thought went hand in hand with China’s modernization.
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馮延巳 陽春集 研究 = A study of Feng Yansi's The Collection of Yang Chun / Study of Feng Yansi's The Collection of Yang Chun;"馮延巳陽春集研究"薛寶嫦 January 2000 (has links)
University of Macau / Faculty of Social Sciences and Humanities / Department of Chinese
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