Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In co...Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In contrast to the conventional landfill, this paper introduces a new technique named bioreactor landfill (BL). Mechanisms, operation conditions as well as the advantages and disadvantages of BL are also discussed in this paper.展开更多
We introduce the artificial fish swarm algorithm for heading motion model identification and control parameter optimization problems for the“Ocean Rambler”unmanned wave glider(UWG).First,under certain assumptions,th...We introduce the artificial fish swarm algorithm for heading motion model identification and control parameter optimization problems for the“Ocean Rambler”unmanned wave glider(UWG).First,under certain assumptions,the rigid-flexible multi-body system of the UWG was simplified as a rigid system composed of“thruster+float body”,based on which a planar motion model of the UWG was established.Second,we obtained the model parameters using an empirical method combined with parameter identification,which means that some parameters were estimated by the empirical method.In view of the specificity and importance of the heading control,heading model parameters were identified through the artificial fish swarm algorithm based on tank test data,so that we could take full advantage of the limited trial data to factually describe the dynamic characteristics of the system.Based on the established heading motion model,parameters of the heading S-surface controller were optimized using the artificial fish swarm algorithm.Heading motion comparison and maritime control experiments of the“Ocean Rambler”UWG were completed.Tank test results show high precision of heading motion prediction including heading angle and yawing angular velocity.The UWG shows good control performance in tank tests and sea trials.The efficiency of the proposed method is verified.展开更多
2019 was one of the hottest years in recent decades,with widespread heatwaves over many parts of the world,including Africa.However,as a developing and vulnerable region,the understanding of recent heatwave events in ...2019 was one of the hottest years in recent decades,with widespread heatwaves over many parts of the world,including Africa.However,as a developing and vulnerable region,the understanding of recent heatwave events in Africa is limited.Here,the authors incorporated different climate datasets,satellite observations,and population estimates to investigate patterns and hotspots of major heatwave events over Africa in 2019.Overall,2019 was one of the years that experienced the strongest heatwaves in terms of intensity and duration since 1981 in Africa.Heatwave hotspots were clearly identified across western-coastal,northeastern,southern,and equatorial Africa,where major cities and human populations are located.The proportion of urban agglomerations(population)exposed to extreme(99 th percentile)heatwaves in the Northern Hemisphere and Southern Hemisphere rose from 4%(5 million people)and 15%(17 million people),respectively,in the baseline period of 1981-2010 to36%(43 million people)and 57%(53 million people),respectively,in 2019.Heatwave patterns and hotspots in 2019 were related to anomalous seasonal change in atmospheric circulation and above-normal sea surface temperature.Without adaptation to minimize susceptibility to the effects of heatwave events,the risks they pose in populated areas may increase rapidly in Africa.展开更多
Willa Cather （1873-1947） is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American s...Willa Cather （1873-1947） is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American southwest. For long Willa Cather＇s pioneer works have gained great critical acclaim and have been interpreted from different perspectives such as mythicism, romanticism, and feminism. This paper, interpreting Willa C ather＇ s classical pioneer works of the three periods from the 1920s to the 1930s-My A ntonia （ 1918）, A Lost Lady （1923）, and ＂Neighbor Rosicky＂ （1930）, is devoted to making a full exploration into the evolution of her ecological thoughts from an ecofeminist perspective. In Willa Cather＇s three pioneer works of different creative stages, she deliberately constructs three eco-worlds as a standard of ecological harmony. In her three eco-worlds, Willa Cather not only investigates the relationship between man and nature, but also involves androcentrism, patriarchy, and other ecofeminist topics. Willa Cather＇s ecological views have undergone changes in her representation of three successive phrases. To interpret Willa Cather＇s pioneer works from the perspective of ecofeminism can provide a deeper comprehension about her works and her ecological thoughts for the world.展开更多
Wordsworth＇s Prelude of 1799 is presenting a poetic voice of education through nature that goes beyond nature. This essay considers the cycles and developments in the poem under the four themes of Unity; Impression; ...Wordsworth＇s Prelude of 1799 is presenting a poetic voice of education through nature that goes beyond nature. This essay considers the cycles and developments in the poem under the four themes of Unity; Impression; Time, Age and Season; Revolution.展开更多
Informed by the framework of Halliday＇s Systemic Functional Grammar, this paper compares ＂The Little Mermaid＂ （1872） by Hans Christian Andersen and its parodic version ＂The Little Mer-persun＂ （1995） by James ...Informed by the framework of Halliday＇s Systemic Functional Grammar, this paper compares ＂The Little Mermaid＂ （1872） by Hans Christian Andersen and its parodic version ＂The Little Mer-persun＂ （1995） by James Finn Garner. Andersen＇s story creates gender stereotype by under-representing the heroine as an effectual Actor and Sayer but establishing the image of the hero as a powerful Actor and assertive Sayer. Garner＇s story, on the other hand, tends to subvert the traditional gender stereotype by representing the heroine as a more dynamic Actor and Sayer than the hero and by reversing the power relationship between the two. These differing characterizations reflect the two competing literary traditions and embedded ideologies of romanticist fairy tale genre and modem ＂politically-correct＂ parodic satire展开更多
Hawthorne is an influential romantic novelist in America in 19thcentury. He is famous in handling the application of symbolism. The Scarlet Letter makes the American writer Nathaniel Hawthorne known all around the wor...Hawthorne is an influential romantic novelist in America in 19thcentury. He is famous in handling the application of symbolism. The Scarlet Letter makes the American writer Nathaniel Hawthorne known all around the world. The vivid description of the four characters in the novel shows that Hawthorne is skilful in the use of symbolism. The Scarlet Letter was published in 1850 and it is Hawthorne＇s most important symbolic novel, which stands as the best work of Hawthorne. It has great significance in America literature. Hawthorne used symbolism through the whole novel. The most obvious symbol is the four main characters in the novel： Hester Prynne, Arthur Dimmesdale, Roger Chillingworth and Pearl have their own symbolic meanings. This thesis is written in the hope to introduce ananalyze the symbolic meaning of the four main characters in The Scarlet Letter.展开更多
Healthcare fraud, waste, and abuse losses are estimated to be as much as $700 billion per year. These losses contribute to rapidly increasing healthcare costs for all Americans and the lack of healthcare or the malpra...Healthcare fraud, waste, and abuse losses are estimated to be as much as $700 billion per year. These losses contribute to rapidly increasing healthcare costs for all Americans and the lack of healthcare or the malpractice of healthcare for money motivations can result in death. The purpose of this article is to describe several different types of healthcare frauds that occurred and to offer suggestions related to the prevention and/or detection of this type of fraud. With a better understanding of the frauds that can take place, auditors can help protect society from both unfair healthcare costs and medical problems.展开更多
Interaction between the Quasi-Biennial Oscillation in far west equatorialPacific (QBOWP) and the El Nino/Southern Oscillation (ENSO) is studied using a new conceptual model.In this conceptual model, the QBOWP effects ...Interaction between the Quasi-Biennial Oscillation in far west equatorialPacific (QBOWP) and the El Nino/Southern Oscillation (ENSO) is studied using a new conceptual model.In this conceptual model, the QBOWP effects on ENSO are achieved through two ways: (1) the oceanicKelvin wave along equatorial Pacific, and (2) the Atmospheric Walker Circulation anomaly, while ENSOeffects on QBOWP can be accomplished by the atmospheric Walker Circulation anomaly. Diagnosisanalysis of the model results shows that the Atmospheric bridge (Walker circulation) plays a moreimportant role in interaction between the ENSO and QBOWP than the oceanic bridge (oceanic Kelvinwave along equatorial Pacific); It is found that by the interaction of the ENSO and QBOWP, a freeENSO oscillation with 3-5 years period could be substituted by a oscillation with the quasi-biennialperiod, and the dominant period of SST anomaly and wind anomaly in the far west equatorial Pacifictends to be prolonged with enhanced ENSO forcing. Generally, the multi-period variability in thecoupled Atmosphere-Ocean System in the Tropical Pacific can be achieved through the interactionbetween ENSO and QBOWP.展开更多
文摘Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In contrast to the conventional landfill, this paper introduces a new technique named bioreactor landfill (BL). Mechanisms, operation conditions as well as the advantages and disadvantages of BL are also discussed in this paper.
基金Project(51779052)supported by the National Natural Science Foundation of ChinaProject(QC2016062)supported by the Natural Science Foundation of Heilongjiang Province,China+2 种基金Project(614221503091701)supported by the Research Fund from Science and Technology on Underwater Vehicle Laboratory,ChinaProject(LBH-Q17046)supported by the Heilongjiang Postdoctoral Funds for Scientific Research Initiation,ChinaProject(HEUCFP201741)supported by the Fundamental Research Funds for the Central Universities,China
文摘We introduce the artificial fish swarm algorithm for heading motion model identification and control parameter optimization problems for the“Ocean Rambler”unmanned wave glider(UWG).First,under certain assumptions,the rigid-flexible multi-body system of the UWG was simplified as a rigid system composed of“thruster+float body”,based on which a planar motion model of the UWG was established.Second,we obtained the model parameters using an empirical method combined with parameter identification,which means that some parameters were estimated by the empirical method.In view of the specificity and importance of the heading control,heading model parameters were identified through the artificial fish swarm algorithm based on tank test data,so that we could take full advantage of the limited trial data to factually describe the dynamic characteristics of the system.Based on the established heading motion model,parameters of the heading S-surface controller were optimized using the artificial fish swarm algorithm.Heading motion comparison and maritime control experiments of the“Ocean Rambler”UWG were completed.Tank test results show high precision of heading motion prediction including heading angle and yawing angular velocity.The UWG shows good control performance in tank tests and sea trials.The efficiency of the proposed method is verified.
基金funded by the National Natural Science Foundation of China[grant numbers 41861124005 and 41675079]the first author was a recipient of a research studentship provided by the CAS-TWAS President fellowship。
文摘2019 was one of the hottest years in recent decades,with widespread heatwaves over many parts of the world,including Africa.However,as a developing and vulnerable region,the understanding of recent heatwave events in Africa is limited.Here,the authors incorporated different climate datasets,satellite observations,and population estimates to investigate patterns and hotspots of major heatwave events over Africa in 2019.Overall,2019 was one of the years that experienced the strongest heatwaves in terms of intensity and duration since 1981 in Africa.Heatwave hotspots were clearly identified across western-coastal,northeastern,southern,and equatorial Africa,where major cities and human populations are located.The proportion of urban agglomerations(population)exposed to extreme(99 th percentile)heatwaves in the Northern Hemisphere and Southern Hemisphere rose from 4%(5 million people)and 15%(17 million people),respectively,in the baseline period of 1981-2010 to36%(43 million people)and 57%(53 million people),respectively,in 2019.Heatwave patterns and hotspots in 2019 were related to anomalous seasonal change in atmospheric circulation and above-normal sea surface temperature.Without adaptation to minimize susceptibility to the effects of heatwave events,the risks they pose in populated areas may increase rapidly in Africa.
文摘Willa Cather （1873-1947） is one of the greatest women writers in the history of American literature, whose reputation centers on her novels about celebrating pioneer immigrants on Nebraska prairie and the American southwest. For long Willa Cather＇s pioneer works have gained great critical acclaim and have been interpreted from different perspectives such as mythicism, romanticism, and feminism. This paper, interpreting Willa C ather＇ s classical pioneer works of the three periods from the 1920s to the 1930s-My A ntonia （ 1918）, A Lost Lady （1923）, and ＂Neighbor Rosicky＂ （1930）, is devoted to making a full exploration into the evolution of her ecological thoughts from an ecofeminist perspective. In Willa Cather＇s three pioneer works of different creative stages, she deliberately constructs three eco-worlds as a standard of ecological harmony. In her three eco-worlds, Willa Cather not only investigates the relationship between man and nature, but also involves androcentrism, patriarchy, and other ecofeminist topics. Willa Cather＇s ecological views have undergone changes in her representation of three successive phrases. To interpret Willa Cather＇s pioneer works from the perspective of ecofeminism can provide a deeper comprehension about her works and her ecological thoughts for the world.
文摘Wordsworth＇s Prelude of 1799 is presenting a poetic voice of education through nature that goes beyond nature. This essay considers the cycles and developments in the poem under the four themes of Unity; Impression; Time, Age and Season; Revolution.
文摘Informed by the framework of Halliday＇s Systemic Functional Grammar, this paper compares ＂The Little Mermaid＂ （1872） by Hans Christian Andersen and its parodic version ＂The Little Mer-persun＂ （1995） by James Finn Garner. Andersen＇s story creates gender stereotype by under-representing the heroine as an effectual Actor and Sayer but establishing the image of the hero as a powerful Actor and assertive Sayer. Garner＇s story, on the other hand, tends to subvert the traditional gender stereotype by representing the heroine as a more dynamic Actor and Sayer than the hero and by reversing the power relationship between the two. These differing characterizations reflect the two competing literary traditions and embedded ideologies of romanticist fairy tale genre and modem ＂politically-correct＂ parodic satire
文摘Hawthorne is an influential romantic novelist in America in 19thcentury. He is famous in handling the application of symbolism. The Scarlet Letter makes the American writer Nathaniel Hawthorne known all around the world. The vivid description of the four characters in the novel shows that Hawthorne is skilful in the use of symbolism. The Scarlet Letter was published in 1850 and it is Hawthorne＇s most important symbolic novel, which stands as the best work of Hawthorne. It has great significance in America literature. Hawthorne used symbolism through the whole novel. The most obvious symbol is the four main characters in the novel： Hester Prynne, Arthur Dimmesdale, Roger Chillingworth and Pearl have their own symbolic meanings. This thesis is written in the hope to introduce ananalyze the symbolic meaning of the four main characters in The Scarlet Letter.
文摘Healthcare fraud, waste, and abuse losses are estimated to be as much as $700 billion per year. These losses contribute to rapidly increasing healthcare costs for all Americans and the lack of healthcare or the malpractice of healthcare for money motivations can result in death. The purpose of this article is to describe several different types of healthcare frauds that occurred and to offer suggestions related to the prevention and/or detection of this type of fraud. With a better understanding of the frauds that can take place, auditors can help protect society from both unfair healthcare costs and medical problems.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 40333030 and 40233033).
文摘Interaction between the Quasi-Biennial Oscillation in far west equatorialPacific (QBOWP) and the El Nino/Southern Oscillation (ENSO) is studied using a new conceptual model.In this conceptual model, the QBOWP effects on ENSO are achieved through two ways: (1) the oceanicKelvin wave along equatorial Pacific, and (2) the Atmospheric Walker Circulation anomaly, while ENSOeffects on QBOWP can be accomplished by the atmospheric Walker Circulation anomaly. Diagnosisanalysis of the model results shows that the Atmospheric bridge (Walker circulation) plays a moreimportant role in interaction between the ENSO and QBOWP than the oceanic bridge (oceanic Kelvinwave along equatorial Pacific); It is found that by the interaction of the ENSO and QBOWP, a freeENSO oscillation with 3-5 years period could be substituted by a oscillation with the quasi-biennialperiod, and the dominant period of SST anomaly and wind anomaly in the far west equatorial Pacifictends to be prolonged with enhanced ENSO forcing. Generally, the multi-period variability in thecoupled Atmosphere-Ocean System in the Tropical Pacific can be achieved through the interactionbetween ENSO and QBOWP.
