The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

凿井水下底卸式自动卸料吊桶

吊桶是立井井筒开凿时期提升矸石和运送材料及升降人员的主要容器,吊桶的卸矸目前多采用挂钩式或座钩式卸料方式;但是随着矿井的开凿深度不断延伸,在过透水层时,由于探放水不及时或涌出水比较大,超出了井筒的排水量,或者是由于冷冻井在解冻后,井筒的井筒质量不过关,各别井壁也会发生透水事故;这就会出现淹井事故,有时淹井深度达二三百米。对于处理这种淹井事故,往往只有一个办法,那就是用沙或混凝土对井筒回填;这就需要吊桶在下到几百米下的水底自动把料卸掉,但现在矿井常用的挂钩式吊桶和座钩式吊桶已经不能满足这个需要了。     

Exploiting commodity momentum along the futures curves

This study examines novel momentum strategies in commodities futures markets that incorporate term-structure information. We show that momentum strategies that invest in contracts on the futures curve with the largest expected roll-yield or the strongest momentum earn significantly higher risk-adjusted returns than a traditional momentum strategy, which only invests in the nearest contracts. Moreover, when incorporating conservative transaction costs we observe that our low-turnover momentum strategy more than doubles the net return compared to a traditional momentum strategy.     

Random sources correlations and carbon futures pricing

For a long time, the correlation between random sources has never been considered in carbon futures pricing, which virtually exists. We document the presence of high correlation between variations in convenience yields of carbon futures with different maturities, whose essence is correlation between random sources. Correlation of random sources arises from the long coverage of convenience yield of carbon emission spot and the complementarity in expiration between carbon futures with different maturities. Since if random sources are correlated will significantly affect the dynamics of convenience yield and finally affect futures prices, we introduce quantum field method to account for the impact of this correlation on futures prices, and proposes the correlation between random sources extended HJM convenience yield model (CRS-HJM-CYM). Empirical results indicate CRS-HJM-CYM performs better than traditional model owing to the role of correlation, which means the correlation between random sources is a pivotal factor in carbon futures pricing.     

西气东输工程用大口径X70级螺旋埋弧焊钢管的力学性能研究

以大量生产检验数据,对西气东输管线的力学性能进行了综合研究,并对其受包申格效应的影响情况进行了分析.     

Factor pricing in commodity futures and the role of liquidity

This paper empirically investigates the pricing factors and their associated risk premiums of commodity futures. Existing pricing factors in equity and bond markets, including market premium and term structure, are tested in commodity futures markets. Hedging pressure in commodity futures markets and momentum effects is also considered. This study combines these factors to discuss their importance in explaining commodity future returns, while the literature has studied these factors separately. One of the important pricing factors in equity and bond markets is liquidity, but its role as a pricing factor in commodity futures markets has not yet been studied. To our knowledge, this research is the first to study liquidity as a pricing factor in commodity futures. The risk premiums of two momentum factors and speculators’ hedging pressure range from 2% to 3% per month and are greater than the risk premiums of roll yield (0.8%) and liquidity (0.5%). The result of a significant liquidity premium suggests that liquidity is priced in commodity futures.     

Does the bond‐stock earnings yield differential model predict equity market corrections better than high P/E models?

We extend the literature on crash prediction models in three main ways. First, we explicitly relate crash prediction measures and asset pricing models. Second, we present a statistical significance test for crash prediction models. Finally, we propose a definition and a measure of robustness for these models. We apply our statistical test and measure the robustness of selected model specifications of the Price‐Earnings (P/E) ratio and Bond Stock Earning Yield Differential (BSEYD) measures. This analysis shows that the BSEYD and P/E ratios, were statistically significant robust predictors of corrections on the US equity market over the period 1964 to 2014.     

税负效应与除息日股票价格行为研究——来自A股市场的实证证据

本文基于我国A股市场相关数据对除息日股价行为的税负效应进行全面检验,实证结果表明股息和资本利得税率对除息日股价波动行为具有显著影响,税负效应理论存在于A股市场,但除息日股价波动行为不能完全由税负效应进行解释,另外实证研究还发现我国A股市场不存在税收诱导客户效应。     

Government contracts and US bond yield spreads: A study on costs and benefits of materialized political connections

In a 1991–2013 sample of bonds issued by US public firms, we find that the cost of debt (yield spread relative to comparable Treasuries) of suppliers to government agencies is contingent on the strategic importance of the supplier's industry. The yield spreads for strategically unimportant government suppliers are higher than for firms that are not government suppliers. If government contracts serve as tangible evidence of political connections, these higher yield spreads indicate that weaker corporate governance as a cost of political connections outweighs the benefits of said connections. For the subsample of government suppliers from strategically important industries, where the benefits of implicit bailout guarantees and revenue stability outweigh the corporate governance problems, the cost of debt is lower than for firms that are not government suppliers. The higher (lower) cost of debt for strategically unimportant (strategically important) suppliers is confined to contracting with the federal government. Our findings are robust to alternative variable and sample specifications, and to endogeneity concerns.     

Money,Asset Prices,and the Liquidity Premium

This paper examines the effect of monetary policy on the market value of the liquidity services that financial assets provide, known as the liquidity premium. The theory predicts that money supply and nominal interest rates have positive effects on the liquidity premium, but asset supply has a negative effect. The empirical analysis with U.S. data confirms the theoretical predictions. The theory also proposes that the liquidity properties of assets can cause negative nominal yields when the money holding cost is low and liquid assets are scarce. The suggestive empirical findings in Switzerland to support this theoretical result are presented.