Chang’e-6 Returns with Samples from Far Side of Moon

At 2:07 pm GMT+8 on June 25,2024,the returner of Chang’e-6,China’s lunar detector,touched down on the ground surface of the preset landing site in Inner Mongolia of China.Onboard were samples first-ever collected from the far side of the Moon,the mysterious kingdom that had resisted visits from the human world.This soft landing has thus crowned the high-profile mission with a complete success.

Performance of bottleneck shifting for remanufacturing system considering returns' quality grading

Aimed at the remanufacturing system, the effect of the uncertainty of returns＇ quality on bottleneck shifting is investigated. A novel definition of bottleneck station is presented and the probability of a station becoming a bottleneck is also given. By calculating the effective output, the effective operation time （EOT） and the ratio of EOT of each station, the system＇s current bottleneck of effective output time is determined. By calculating the probability coefficient of variation and index of bottleneck shifting, the quantitative performance of bottleneck shifting is obtained. Discrete event simulation and the experiment design method are adopted to simulate the system, in which the proportion of quality grading, repair rates and process routes are considered. The case study shows that the uncertainty of returns＇ quality greatly increases the probability of bottleneck shifting, and with the increase of the discrete degree of the returns＇ repair rate, the bottleneck shifting phenomenon is more obvious. Furthermore, bottleneck shifting is closely related to the process route of the dominating returns＇ quality grade.

Price and retailer's service level decision in a supply chain under consumer returns

To investigate the optimal retail price and service level in a supply chain under consumer returns, a consumer returns model under the retailer＇s service provision is built. The optimal decision results and optimal profits are obtained in the vertical integration game and the manufacturer Stackelberg game, respectively. Through comparing the optimal profits with service provision with those of no service provision, the boundary conditions that the retailer＇s service should be provided are derived. The results show that in the manufacturer Stackelberg game, the optimal profit of the retailer and the manufacturer with service is always superior to that of a no service provision. However, in the vertical integration game, the supply chain can only benefit from the service under certain conditions. Finally, through numerical examples, the impacts of the cost for providing services and the consumer return rate on the optimal decisions are analyzed.

Effects of returns on composition,microstructure and mechanical properties of GH4169 superalloy

To recycle the returned alloy effectively, effects of returns proportion on alloy composition, microstructure and compression properties of superalloy GH4169 were studied by means of scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and thermal-mechanical simulator. The results show that returns addition has no significant effect on the main alloy elements content and the principle precipitates, but increases the volume fraction of Al_2O_3 inclusions, resulting in the increase of oxygen level of GH4169 alloy. Returns addition does not change the elastic and plastic deformation process at room temperature or at 1,150 °C, but high returns proportion GH4169 alloy shows improved compression strength and yield strength. The alloy with 100% returns shows a maximum compression strength 1,153.45 MPa at room temperature, while the alloy with 80% returns has a maximum value 69.3 MPa at 1,150 °C. Returns addition increases fluctuation range and reduces the stability of yield strength and compression strength of GH4169 alloy at room temperature. It is noted that the volume fraction and the size of Al_2O_3, and the fraction of Laves phase reach their maximum values in the GH4169 alloy with 60% returns, which exhibits maximum yield strength of 516.65 MPa at room temperature and 62.17 MPa at 1,150 °C.

The chaotic behavior among the oil prices, expectation of investors and stock returns: TAR-TR-GARCH copula and TAR-TR-TGARCH copula

This paper has two aims. The first one is to investigate the existence of chaotic structures in the oil prices, expectations of investors and stock returns by combining the Lyapunov exponent and Kolmogorov entropy, and the second one is to analyze the dependence behavior of oil prices, expectations of investors and stock returns from January 02, 1990, to June06, 2017. Lyapunov exponents and Kolmogorov entropy determined that the oil price and the stock return series exhibited chaotic behavior. TAR-TR-GARCH and TAR-TR-TGARCH copula methods were applied to study the co-movement among the selected variables. The results showed significant evidence of nonlinear tail dependence between the volatility of the oil prices, the expectations of investors and the stock returns. Further, upper and lower tail dependence and comovement between the analyzed series could not be rejected. Moreover, the TAR-TR-GARCH and TAR-TR-TGARCH copula methods revealed that the volatility of oil price had crucial effects on the stock returns and on the expectations of investors in the long run.

China's Latest Moon Mission Returns New Lunar Rocks

After a quick visit to the Moon in December 2020,China’s Chang'e 5 mission has delivered back to Earth the first new specimens of lunar rock and soil since 1976[1].Scooped from a volcanic location not sampled before,the material may provide insights into the Moon's evolution and the history of the solar system.The mission also demonstrates a new level of technical sophistication for the Chinese space program and provides a blueprint for future expeditions to return samples from other bodies in the solar system,said Jim Head,a professor of geological sciences at Brown University in Providence,RI,USA.

Effect of returns on microstructure and mechanical properties of Al-Cu based alloys

It is well known that maximal utilization of the returns can be beneficial for cost reduction,preservation of natural resources and protection of the environment,by making them into recycled Al-Cu alloys.In this study,the influences of returns on the microstructure and mechanical properties of Al-Cu alloys have been investigated by means of optical microscopy and scanning electron microscopy.The results showed that the returns could be used to produce recycled Al-Cu alloys with fine and uniform microstructure and excellent mechanical properties,including ultimate tensile strength,yield strength and ductility.It was found that the maximum performance of the recycled Al-Cu alloy in their properties could be achievable when the returns content was 20wt.%,which gave 219 MPa,87.16 MPa and 12.15% at as-cast state,and 525 MPa,445.3 MPa and 14.14% after heat treated,in their tensile strengths,yield strengths and elongations,respectively.These values were much higher than those of primary alloy.

Returns to Education in China:1989-2011

Using China Health and Nutrition Survey(CHNS) data between 1989 and 2011, this paper measures the returns to education in China based on the Mincer earnings function and reaches the following findings through an analysis of the tendency of continuous variations over a long timeframe: returns to education are on the rise within the range of samples both under relative and absolute scenarios; returns to different levels of education are characterized by increasing marginal return; no significant difference exists between the returns to junior middle school and the returns to primary school education. Further discussions consider that the requirements of job positions for the overall competence of personnel, differentiated decline of corporate demand for recruitment, lack of an evaluation system in the labor market, information asymmetry in the job market, the development strategy adopted in a particular stage of history and the current slow progress of economic transition have jointly led to the underemployment of college graduates and the great enthusiasm of parents investing in higher education for their children. Conclusions of this paper not only have important practical relevance to the ongoing implementation of China's innovation-driven development strategy, but offer inspirations for the new round of educational reform as well.

Optimizing Nutrient Use Efficiency and Returns from Soybean Production under Smallholders in Three Agro-Ecologies of Malawi

Field trials were conducted to determine the economically optimum fertilizer rates for soybean production and for optimizing net profits in Dedza, Lilongwe and Salima Districts of Malawi. The effects of PK fertilizer rates on rain use efficiency (RUE), harvest index, agronomic use efficiency of phosphorous (AEP) and potassium (AEK), and value cost ratio (VCR) were evaluated. The applied diagnostic PK fertilizer rates significantly improved soybean grain yields, harvest index, rainwater use efficiency, AEP, AEK and returns to fertilizer use expressed as value cost ratio (VCR). However, the results differed significantly

On the volatility of daily stock returns of Total Nigeria Plc: evidence from GARCH models, value-at-risk and backtesting

This study investigates the volatility in daily stock returns for Total Nigeria Plc using nine variants of GARCH models:sGARCH,girGARCH,eGARCH,iGARCH,aGARCH,TGARCH,NGARCH,NAGARCH,and AVGARCH along with value at risk estimation and backtesting.We use daily data for Total Nigeria Plc returns for the period January 2,2001 to May 8,2017,and conclude that eGARCH and sGARCH perform better for normal innovations while NGARCH performs better for student t innovations.This investigation of the volatility,VaR,and backtesting of the daily stock price of Total Nigeria Plc is important as most previous studies covering the Nigerian stock market have not paid much attention to the application of backtesting as a primary approach.We found from the results of the estimations that the persistence of the GARCH models are stable except for few cases for which iGARCH and eGARCH were unstable.Additionally,for student t innovation,the sGARCH and girGARCH models failed to converge;the mean reverting number of days for returns differed from model to model.From the analysis of VaR and its backtesting,this study recommends shareholders and investors continue their business with Total Nigeria Plc because possible losses may be overcome in the future by improvements in stock prices.Furthermore,risk was reflected by significant up and down movement in the stock price at a 99%confidence level,suggesting that high risk brings a high return.

The time‑varying effects of oil prices on oil-gas stock returns of the fragile five countries

This study analyzes oil price exposure of the oil–gas sector stock returns for the fragile five countries based on a multi-factor asset pricing model using daily data from 29 May 1996 to 27 January 2020.The endogenous structural break test suggests the presence of serious parameter instabilities due to fluctuations in the oil and stock markets over the period under study.Moreover,the time-varying estimates indicate that the oil–gas sectors of these countries are riskier than the overall stock market.The results further suggest that,except for Indonesia,oil prices have a positive impact on the sectoral returns of all markets,whereas the impact of the exchange rates on the oil–gas sector returns varies across time and countries.

Baidu index and predictability of Chinese stock returns

A number of studies have investigated the predictability of Chinese stock returns with economic variables.Given the newly emerged dataset from the Internet,this paper investigates whether the Baidu Index can be employed to predict Chinese stock returns.The empirical results show that 1)the Search Frequency of Baidu Index(SFBI)can predict next day’s price changes;2)the stock prices go up when individual investors pay less attention to the stocks and go down when individual investors pay more attention to the stocks;3)the trading strategy constructed by shorting on the most SFBI and longing on the least SFBI outperforms the corresponding market index returns without consideration of the transaction costs.These results complement the existing literature on the predictability of Chinese stock returns and have potential implications for asset pricing and risk management.

Straw return increases crop production by improving soil organic carbon sequestration and soil aggregation in a long-term wheat-cotton cropping system

Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system.

A perspective on recent methods on testing predictability of asset returns

This paper highlights some recent developments in testing predictability of asset returns with focuses on linear mean regressions, quantile regressions and nonlinear regression models. For these models, when predictors are highly persistent and their innovations are contemporarily correlated with dependent variable, the ordinary least squares estimator has a finite-sample bias, and its limiting distribution relies on some unknown nuisance parameter, which is not consistently estimable. Without correcting these issues, conventional test statistics are subject to a serious size distortion and generate a misleading conclusion in testing pre- dictability of asset returns in real applications. In the past two decades, sequential studies have contributed to this subject and proposed various kinds of solutions, including, but not limit to, the bias-correction procedures, the linear projection approach, the IVX filtering idea, the variable addition approaches, the weighted empirical likelihood method, and the double-weight robust approach. Particularly, to catch up with the fast-growing literature in the recent decade, we offer a selective overview of these methods. Finally, some future research topics, such as the econometric theory for predictive regressions with structural changes, and nonparametric predictive models, and predictive models under a more general data setting, are also discussed.

Macao Returns Home

In1553,PortugueselandedonMacaobeachwhereAMaTemplewaslocatedtodrytheirwatersoakedgoods.Theydecidedtosettleintheareaandeventuallyinstitutedcolonialruleovertheisland.InJuly1844,thecorruptQingcourtsignedtheunequalWangxiaTreatyuponaroundstonetableintherea...

Cassava Yield, Garrification Traits and Economic Returns as Influenced by Different Genotypes in an Ultisol

Field trials were conducted at the University of Uyo Teaching and Research Farm in 2009/2010 and 2010/2011 to evaluate cassava yield, garrification traits, and economic returns as influenced by genotypes grown in an ultisol. Uyo is located between latitudes 4&deg;30' and 5&deg;27'N and longitudes 7&deg;50'E and 80&deg;20'E. The area, which lies within the humid tropical rainforest zone of southeastern Nigeria, has an annual mean rainfall of 2500 mm with a bimodal rainfall pattern, monthly sunshine of 3.14 hours, and a mean annual temperature of 28&deg;C. The experimental site was previously put into cultivation of some arable crops such as fluted pumpkin, okra, and waterleaf before it was fallowed for two years. A randomized complete block design, replicated three times was used. Treatments were 16 cassava genotypes (AR1-82, NR02/0028, NR03/0174, CR12-45, NR03/0211, TMS98/2132, TMS01/1206, TMS01/1368, TMS01/1371, CR36-5, NR02/0007, NR03/0155, AR37-108, TMS01/1412, TMS30572 and local best variety “Obubit okpo”). Results obtained via combined (pooled) analysis of the two seasons indicated that cassava yield differed significantly among the genotypes. NR02/0018 (42.50 t/ha) out-yielded others by 17% - 52% followed by NR 02/0007 (35.42 t/ha), and NR 03/0155 (32.08 t/ha). TMS 98/2132 had the most preferred garrification attributes followed by NR 02/0018, NR 02/0007, and NR03/01155. NR 02/0018 genotype gave the highest economic returns followed by NR 02/0007 and NR03/0155. NR02/0018 superseded others in yield, garrification traits, and economic returns, which is therefore recommended.

A model of regional economic development with increasing returns

This paper develops mathematically and empirically tractable regional and interregional model of economic devel-opment with increasing returns to scale (IRS) under the neoclassical assumptions. A one-sector, two-region model in which one region exhibits IRS is presented and the whole nation presents constant returns to scale. The development of the local IRS economy is shown to be constrained to a “moving equilibrium” path. The preliminary empirical results are sufficiently supportive of the argument to encourage further research along the lines of the model. In particular, the neoclassical model does not predict negative coefficients on the real rental value of capital in regressions explaining population or employment relative to that in the nation.

Improving crop yield, N uptake and economic returns by intercropping barley or canola with pea

Two field experiments were conducted from 2009 to 2011 on a Gray Luvisol (Typic Haplocryalf) loam at Star City, Saskatchewan, Canada, to determine the effectiveness of intercropping barley or canola with pea in improving crop yield, total N uptake, seed quality, Land Equivalency Ratio (LER) and economic returns compared to barley, canola or pea grown as monocultures. Average seed yields of barley-pea or canola-pea intercrops were usually greater than those of barley, canola or pea as sole crops. In intercrops, application of N fertilizer increased seed yield of barley or canola but had only slight beneficial effect on the combined seed yield of both crops together. The LER values for intercrops were usually much greater than 1, suggesting less land requirements of intercropping systems than monoculture for the same seed yield. Net returns were lowest for barley as sole crop. Without applied N, net returns were slightly lower for barley-pea intercrop and slightly greater for canola-pea intercrop than pea as a sole crop. Generally, protein concentration in canola or barley seed was higher and oil concentration in canola seed was lower in intercrop combinations compared to sole crops. Response trends of total N uptake in seed or straw were usually similar to that of seed or straw yield. In conclusion, intercropping barley or canola with pea improved yield, N uptake and net returns, suggesting the potential of barley-pea or canola-pea intercrops and pea for organic farming systems.

The Law of Diminishing Returns in Determining the Environmental Cost of Mining in the Eastern Mediterranean Sea

Environmental standards,as independent/explanatory variables of C21 capital costing functions,may refer to parts of space that we want to control in order to protect subsystems that are particularly sensitive and/or importance.In these cases,we need a quantitative relationship that links the environmental characteristics of the source of pollution to those of the reference/control points.In this article we will identify the capital cost functions C21=f(Sf),where Sf is a spatially distributed parameter(e.g.BOD),characteristic of an environmental model.

Bull and Bear Dynamics of the Nigeria Stock Returns Transitory via Mingled Autoregressive Random Processes

This paper expounds the nitty-gritty of stock returns transitory, periodical behavior of its markets’ demands and cyclical-like tenure-changing of number of the stocks sold. Mingling of autoregressive random processes via Poisson and Extreme-Value-Distributions (Fréchet, Gumbel, and Weibull) error terms were designed, generalized and imitated to capture stylized traits of k-serial tenures (ability to handle cycles), Markov transitional mixing weights, switching of mingling autoregressive processes and full range shape changing predictive distributions (multimodalities) that are usually caused by large fluctuations (outliers) and long-memory in stock returns. The Poisson and Extreme-Value-Distributions Mingled Autoregressive (PMA and EVDs) models were applied to a monthly number of stocks sold in Nigeria from 1960 to 2020. It was deduced that fitted Gumbel-MAR (2:1, 1) outstripped other linear models as well as best fitted among the Poisson and Extreme-Value-Distributions Mingled autoregressive models subjected to the discrete monthly stocks sold series.