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81.
Regime Shifts in Asian Equity and Real Estate Markets 总被引:4,自引:0,他引:4
This paper applies a new statistical technology for identifying regime shifts to analyze recent data on real estate and equity markets in eight developing Far Eastern countries in the 1992–1998 time period. We find that regime shifts in volatility occur in the summer of 1997; however, most of the regime shifts in returns occur in the spring of 1998. While the clustering of regime breaks does not seem to follow any obvious pattern, the country's exposure to trade and firm leverage are important. An analysis of Granger causality suggests that, in most cases, equity returns cause real estate returns but the converse is not true. We also find two-way causality in volatility, suggesting that a common factor drives volatility in these markets. Finally, we provide evidence that the regime shifts generally imply higher relative risk for real estate securities after the estimated breaks. 相似文献
82.
In this study, four similar bench-scale submerged Anoxic/Oxic Membrane Bioreactors (MBR) were used simultaneously to investigate the effects of solids retention time (SRT) on organic and nitrogen removal in MBR for treating domestic wastewater. COD removal efficiencies in all reactors were consistently above 94% under steady state conditions. Complete conversion of NH(4+)-N to NO(3-)-N was readily achieved over a feed NH(4+)-N concentration range of 30 to 50 mg/L. It was also observed that SRT did not significantly affect the nitrification in the MBR systems investigated. The average denitrification efficiencies for the 3, 5, 10 and 20 days SRT operations were 43.9, 32.6, 47.5 and 66.5%, respectively. In general, the average effluent nitrogen concentrations, which were mainly nitrate, were about 22.2, 27.6, 21.7 and 13.9 mg/L for the 3, 5, 10 and 20 days SRT systems, respectively. The rate of membrane fouling at 3 days SRT operation was more rapid than that observed at 5 days SRT. No fouling was noted in the 10 days and 20 days SRT systems during the entire period of study. 相似文献
83.
Brian P. Anderson Stephen D. Makar Stephen H. Huffman 《Research in International Business and Finance》2004,18(2):205-216
Recent studies examining the relationship between stock returns and exchange rate changes have provided evidence that the exchange rate exposure of non-financial companies is reduced by the use of foreign exchange derivatives. Building on such research, this study investigates whether past ineffective derivative hedging contributes to explaining future derivatives use. To the extent that companies monitor the effectiveness of their currency risk management practices, past ineffective hedgers can be expected to modify their future use of foreign exchange derivatives accordingly. In our study of 94 non-financial US multinationals, we provide evidence that the change in derivatives use from 1996–1998 to 1998–2000 can be explained in part by the ineffective hedging of currency risk in 1996–1998, controlling for variables associated with theories of optimal hedging. Additional analyses confirm that such primary results are robust to firm size, the level of foreign operations, and the use of derivatives to partially hedge currency risk. Our results imply that as exchange markets and risk management practices change, the use of derivatives to manage exchange rate risk also changes. Our contribution to this field of study is that we find evidence that past ineffective hedgers tend to increase their future use of FXDs. 相似文献
84.
Naturally occurring UV active compounds, commonly present in almost all source waters, can be rapidly monitored by their ultraviolet absorbance at 260 nm (E260). Herein, the extent of correlation between the E260 and the removal efficiency of the hazardous contaminants, endocrine disrupters and dioxins, were investigated using various treatment and river source waters. The detection of various types of hazardous contaminants using sophisticated analytical methods, such as high resolution gas chromatography (HRGC)/high resolution mass spectrometry (HRMS) and high performance liquid chromatography (HPLC)/inductively coupled plasma (ICP)/mass spectrometry (MS), as well as various short-term bioassays, can require hours or even days for results to be obtained. The removal of the E260 correlated well with those of individual contaminants, such as endocrine disruptor chemicals and dioxins, with the various treatment processes employed. In the plots of the endocrine disrupters against the DOC/E260, a correlation was found with the endocrine activity of the Korean/Japanese river waters employed in this study. 相似文献
85.
拉西瓦水电站工程反拱水垫塘优化设计 总被引:1,自引:0,他引:1
在大型高水头水电站中,拉西瓦水电站是我国第一座采用反拱形水垫塘作为特高拱坝坝后消能建筑物的工程,也是我国现有特高拱坝水垫塘中长度最短、宽度最小的工程,其单位水体消能率接近国际经验控制的最高标准。在无规范明确规定和缺少工程资料的情况下,经一系列科研试验和数值计算,优化了反拱水垫塘结构和排水、抽水系统设计等。其经验丰富了我国坝后消能建筑物的设计内容,对我国规范中反拱水垫塘设计规定以及对其他大型高水头水电站坝后消能防冲建筑物的设计具有重要参考价值。 相似文献
86.
Multilateral Reforms of Trade and Environmental Policy 总被引:1,自引:0,他引:1
The paper analyzes environmental tax policy reform using a competitive model of world trade that includes production‐generated environmental damage (pollution) and trade tariffs. The authors examine the feasibility of Pareto‐improving multilateral reforms of environmental taxes, and show that any environmental tax reform that is mutually welfare‐improving when compensating lump‐sum transfers are assumed is also welfare‐improving when a suitable tariff reform (but no transfers) is combined with the tax changes. Several specific reform proposals are developed. These results expand the feasible set of mutually improving policy proposals for international policy initiatives. 相似文献
87.
Robert H. DeFina 《Review of Income and Wealth》2004,50(1):69-85
The analysis uses March Current Population Survey data to estimate state-level cross-section/time-series models of the effects of the unemployment rate on alternative poverty rates. The measures include the official headcount rate, and alternatives based higher thresholds, revised equivalence scales and income defined as inclusive and exclusive of taxes and cash and in-kind transfers. The estimated effects turn critically on the measurement approaches, both for the total sample population and for four population sub-groups. For several alternative poverty rate measures, the unemployment rate has no significant impact on poverty. By contrast, real per-capita median earnings have strong and consistently negative effects on the poverty rates of all groups studied. The findings thus provide important lessons for researchers exploring the links between economic conditions and poverty, and for policy makers developing poverty reduction strategies. 相似文献
88.
一、令人关注的“双重杠杆”现象“双重杠杆”(Double-Gearing)也有人称之为双向杠杆,是指日本银行拥有大量的保险公司证券(通常以次级贷款和盈余票据形式持有),人寿保险公司也拥有大量的银行次级债券和股票,银行和保险公司互相持有彼此发行的证券的现象。在日本,保险公司是银行的大股东,持有每一家城市银行超过10%的股份,银行和保险公司互相交叉持股,依靠彼此信用筹集资金。截至2000年3月,保险公司提供给银行6.7万亿日元次级债券和7.7万亿日元股票,银行提供给保险公司2.3万亿日元盈余票据和次级债券。2000年,由于Chiyoda人寿保险公司、Ky… 相似文献
89.
货币市场与资本市场的长期隔离,造成了资本要素配置效率的损失,究其原因在于资本流动、配置的制度约束,信托制度的不健全,阻碍了信托业的发展,加剧了货币市场与资本市场的隔离程度。通过建立理论模型说明了这一点,并提出政策建议。 相似文献
90.
R H Kadlec 《Water science and technology》2007,56(3):101-108
Twelve research wetlands were operated under varying conditions at a site west of the city of Phoenix. These were constructed as a triplicated design, with zero, one, two and three internal deep zones, all containing an inlet distribution and an outlet collection deep zone, together comprising 12.5-35% of the wetland areas. The water supply was partially nitrified effluent from a city wastewater treatment plant. Total nitrogen was reduced by about 50%, from inflow concentrations between 6 and 8 mg/L. Speciation of the inflow was approximately 25% organic nitrogen, 25% ammonium nitrogen and 50% nitrate nitrogen. Typical outflow concentrations were about 1.2 mg/L organic, 0.5 mg/L ammonium and 0.0-2.5 mg/L nitrate. Rate constants for total nitrogen were 15-20 m/year at 20 degrees C, and 20-30 m/year for nitrate, which agree well with other project reports. Temperature factors averaged 1.100 for total nitrogen, and 1.184 for nitrate. There were no differences in the internal hydraulics with deep zone numbers. Deep zone numbers in the wetlands did not affect nitrogen treatment performance. No differences with deep zone numbers were found for temperature, dissolved oxygen, pH, or nitrogen removals or rate constants. In conjunction with other reported results, there appears to be no large treatment benefit or detriment of incorporating internal deep zones in free water surface wetlands. 相似文献