There is less than half the time left to achieve the United Nations Sustainable Development Goals(SDGs),and progress toward SDGs is obviously insufficient.The contribution of ecosystem services(ES)to SDGs realization ...There is less than half the time left to achieve the United Nations Sustainable Development Goals(SDGs),and progress toward SDGs is obviously insufficient.The contribution of ecosystem services(ES)to SDGs realization has received extensive attentions,but systematic generalization and recognition are still lacking.Based on a review of the progress and challenge of sustainable development,this study summarized ES’s potential contribution to 17 SDGs,and systematically reviewed empirical researches focused on the ES’s contribution to SDGs based on the RepOrting standards for Systematic Evidence Syntheses(ROSES).The results showed that from the 1960s to the 2020s,the ES’s contribution has gradually become more important in sustainable development.ES has potential contribution to all SDGs,but the contribution to different SDGs varies.In the empirical study,ES’s contribution to SDG2,SDG6,SDG13,and SDG15 were strongly focused.ES’s contribution to SDG4,SDG5,SDG10,SDG16,and SDG17 were weakly focused.Most researches have explored the ES’s contribution to SDGs based on ES supply at a single scale,lacking attentions to ES demand and scale differences,and insufficient attentions to intervention factors affecting the ES’s contribution to SDGs.Faced with the above deficiencies,future research could deepen the exploration of ES’s contribution to SDGs from the following four perspectives:clarifying true contributions,exploring leverage point,integrating multi-scale differences,and focusing on intervention factors.展开更多
During high-temperature periods in summer,formaldehyde(HCHO)levels increase due to secondary production.However,recent studies have also shown a rise in the HCHO concentration in winter,but the underlying cause remain...During high-temperature periods in summer,formaldehyde(HCHO)levels increase due to secondary production.However,recent studies have also shown a rise in the HCHO concentration in winter,but the underlying cause remains unclear.Here,HCHO observations in urban Beijing were conducted,the impact of meteorological differences between warm and cold seasons to HCHO concentrations was investigated.Additionally,the positive matrix factorization model was applied to the source apportionment of HCHO,with a focus on changes during pollution events.The results indicated that,during warm seasons,the secondary production of HCHO was driven by high temperature influenced by the low-pressure front,with the contribution of secondary production+background peaking at 85.9% in the afternoon,exhibiting a unimodal diurnal variation.Conversely,during cold seasons,the influence of a uniform pressure field,coupled with weak winds,low boundary layers and high humidity,led to HCHO accumulation from primary emissions,resulting in multiday highconcentration pollution.During the most severe pollution periods,anthropogenic primary emissions contributed up to 91.7%.Therefore,while the contribution of volatile organic compounds to HCHO levels through secondary production has been recognized,the significant impact of primary emissions during cold seasons cannot be overlooked.展开更多
China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on e...China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on evaluating anthropogenic emissions or the natural carbon cycle separately, and few included trade-related(import and export) CO_(2) emissions and its contribution on global warming. Using the Carbon Tracker CT2019 assimilation dataset and China trade emissions from the Global Carbon Project, we found that the change trend of global CO_(2) flux had obvious spatial heterogeneity, which is mainly affected by anthropogenic CO_(2) flux. From 2000 to 2018, carbon emissions from fossil fuels in the world and in China all showed an obvious increasing trend, but the magnitude of the increase tended to slow down.In 2018, the radiative forcing(RF) caused by China's import and export trade was-0.0038 W m^(-2), and the RF caused by natural carbon budget was-0.0027 W m^(-2), offsetting 1.54% and 1.13% of the RF caused by fossil fuels that year, respectively. From 2000 to 2018, the contribution of China's carbon emission from fossil fuels to global RF was 11.32%. Considering China's import and export trade, the contribution of anthropogenic CO_(2) emission to global RF decreased to 9.50%. Furthermore, taking into account the offset of carbon sink from China's terrestrial ecosystems, the net contribution of China to global RF decreased to 7.63%. This study demonstrates that China's terrestrial ecosystem and import and export trade are all mitigating China's impact on global anthropogenic warming, and also confirms that during the research process on climate change, comprehensively considering the carbon budget from anthropogenic and natural carbon budgets is necessary to systematically understand the impacts of regional or national carbon budgets on global warming.展开更多
The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributi...The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributing to impact categories and identifying hotspots for environmental improvements.The research is based on the Life Cycle Assessment(LCA)study of non-load-bearing masonry of concrete blocks performed by the authors.The processes those have demonstrated higher contribution to environmental impacts were identified in the Life Cycle Impact Assessment(LCIA)phase and a detailed analysis was carried out on the main substances derived from these processes.The highest potential impacts in the life cycle of the concrete blocks masonry can be attributed mainly to emissions coming from the production of Portland cement,which explains the peak of impact potential on the blocks production stage,but also the significant impact potential in the use of the blocks for masonry construction,due to the use of cement mortar.The results of this LCA study are part of a major research on the comparative analysis of different typologies of non-load-bearing external walls,which aims to contribute to the creation of a life cycle database of major building systems,to be used by the environmental certification systems of buildings.展开更多
CO_(2) emissions(CEs)pose a growing threat to environmental changes and global warming,attracting extensive attention.Here,we leveraged near-real-time monitoring data spanning 2019 to 2022 to investigate spatiotempora...CO_(2) emissions(CEs)pose a growing threat to environmental changes and global warming,attracting extensive attention.Here,we leveraged near-real-time monitoring data spanning 2019 to 2022 to investigate spatiotemporal heterogeneity,sectoral contributions,provincial spatial correlation,and driving factors influencing CEs at the provincial level in China.Our analysis,integrating Moran’s Index analysis,Spearman correlation analysis,and the Geographically Weighted Regression model,unveiled China’s consistent world-leading CEs,surpassing 10,000 Mt over the study period.Spatially,CEs exhibited a heterogeneous distribution,with markedly higher emissions in eastern and northern regions compared to western and southern areas.Temporally,CEs displayed significant fluctuations,peaking in the fourth quarter before declining in subsequent quarters.Chinese NewYear and COVID-19 had the biggest effects on CEs,with average daily reductions of-20.8%and-18.9%,respectively,compared to the four-year average and the same period in 2019.Sectoral analysis highlighted the power and industry sectors as primary contributors to CEs in China,jointly accounting for 37.9%-40.2%and 43.5%-46.4%of total CEs,respectively.Spatial clustering analysis identified a distinct High-High agglomeration region,predominantly encompassing provinces such as Inner Mongolia,Shandong and Jiangsu.Furthermore,total energy consumption and electricity consumption emerged as significant drivers of CEs,exhibiting correlation coefficients exceeding 0.9,followed by exhaust emissions,population size,and gross domestic product.Moreover,the influence of drivers on provincial CEs exhibited notable spatial heterogeneity,with regression coefficients displaying a decreasing gradient from north to south.These findings provide scientific and technological support to realize the provincial dual-carbon goals in China.展开更多
A finite element and boundary element model of the 100 m X-BOW polar exploration cruise ship is established. The vibrated velocity-excited force admittance matrix is calculated by frequency response analysis, and the ...A finite element and boundary element model of the 100 m X-BOW polar exploration cruise ship is established. The vibrated velocity-excited force admittance matrix is calculated by frequency response analysis, and the vibrated velocity in the stern plate and main engine foundations is tested during the trial trip. Then, the excited force of the propeller and main engine is derived using the vibrated velocity and admittance matrix.Based on the excited force, the cabin-simulated vibrated velocity is compared with the tested vibrated velocity, and the tolerance is within the allowable scope in engineering. Loading the excited forces on the boundary element model, the distribution characteristics of sound level underwater are analyzed. Then, forces excited by the main engine and propeller are loaded on the model, and the contribution ratio of excitation sources to underwater acoustic radiation is analyzed. The result provides a reference for vibration assessment in the early stage and control in the late stage.展开更多
The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indic...The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio selection.Therefore,combining the system contribution rate with system portfolio selection is the focus of this study.It also focuses on calculating the contribution rates of multiple equipment systems with various types of capabilities.The contribution rate is measured by establishing a hierarchical multi-criteria value model from three dimensions.Based on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection strategy.Finally,an illustrative example is presented to verify the feasibility of the proposed model.展开更多
Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimizatio...Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimization of equipment architecture design,the adequate resources allocation,and the joint combat performance.From the system view,this paper proposes a method of weapons equipment portfolios selection(WEPS)based on the contribution rate of weapon systems,providing a new idea for weapon equipment portfolio selection.Firstly,we analyze the WEPS problem and the concept of the contribution rate under the systems background.Secondly,we propose a combat network modeling method for weapon equipment systems based on the function chain.Thirdly,we propose a WEPS method based on the contribution rate,fully considering the correlation relationships between potential weapons and the old weapon systems by the combat network model,under the limitation of capability demands and budget resources,with the objective to maximally increasing the combat ability of weapon systems.Finally,we make a case study with a specific WEPS problem where the whole calculation processes and results are analyzed and exhibited to verify the feasibility and effectiveness of the proposed method model.展开更多
The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate ev...The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network.展开更多
To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation...To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation process of the equipment SoS contribution rate were redefined and standardized.To solve the existing problems in the application of the original contribution rate formula,a modified contribution rate calculation formula is proposed.Finally,the contribution rate evaluation index was divided into latent and explicit variables.The measurement and structural equations in the SEM were used to calculate and analyze the latent variables.The simulation results show that the number of defense lines of air defense weapon equipment has a greater impact on the linear configuration than the group configuration.When the number of K-type air defense weapons is sufficient,the two-layer linear configuration should be adopted with 20 air defense weapon systems.When the number of K-type air defense weapons is insufficient,the single-layer group configuration should be adopted with 12 air defense weapon systems.展开更多
Central East China is an area where both intense hourly precipitation(IHP) events and mesoscale convection systems(MCSs) occur frequently in the warm seasons. Based on mosaics of composite Doppler radar reflectivi...Central East China is an area where both intense hourly precipitation(IHP) events and mesoscale convection systems(MCSs) occur frequently in the warm seasons. Based on mosaics of composite Doppler radar reflectivity and hourly precipitation data during the warm seasons(May to September) from 1 July 2007 to 30 June 2011, the contribution of MCSs to IHP events exceeding 20 mm h^-1 over central East China was evaluated. An MCS was defined as a continuous or quasicontinuous band of 40d BZ reflectivity that extended for at least 100 km in at least one direction and lasted for at least 3h. It was found that the contribution of MCSs to IHP events was 45% on average over central East China. The largest contribution,more than 80%, was observed along the lower reaches of the Yellow River and in the Yangtze River–Huaihe River valleys.These regions were the source regions of MCSs, or along the frequent tracks of MCSs. There were two daily peaks in the numbers of IHP events: one in the late afternoon and one in the early morning. These peaks were more pronounced in July than in other months. MCSs contributed more to the early-morning IHP event peaks than to the late-afternoon peaks. The contributions of MCSs to IHP events with different intensities exhibited no significant difference, which fluctuated around 50% on average over central East China.展开更多
Purpose:This study aims to evaluate the accuracy of authorship attributions in scientific publications,focusing on the fairness and precision of individual contributions within academic works.Design/methodology/approa...Purpose:This study aims to evaluate the accuracy of authorship attributions in scientific publications,focusing on the fairness and precision of individual contributions within academic works.Design/methodology/approach:The study analyzes 81,823 publications from the journal PLOS ONE,covering the period from January 2018 to June 2023.It examines the authorship attributions within these publications to try and determine the prevalence of inappropriate authorship.It also investigates the demographic and professional profiles of affected authors,exploring trends and potential factors contributing to inaccuracies in authorship.Findings:Surprisingly,9.14%of articles feature at least one author with inappropriate authorship,affecting over 14,000 individuals(2.56%of the sample).Inappropriate authorship is more concentrated in Asia,Africa,and specific European countries like Italy.Established researchers with significant publication records and those affiliated with companies or nonprofits show higher instances of potential monetary authorship.Research limitations:Our findings are based on contributions as declared by the authors,which implies a degree of trust in their transparency.However,this reliance on self-reporting may introduce biases or inaccuracies into the dataset.Further research could employ additional verification methods to enhance the reliability of the findings.Practical implications:These findings have significant implications for journal publishers,Beyond authorship:Analyzing contributions in PLOS ONE and Maddi,A.,&the challenges of appropriate attribution highlighting the necessity for robust control mechanisms to ensure the integrity of authorship attributions.Moreover,researchers must exercise discernment in determining when to acknowledge a contributor and when to include them in the author list.Addressing these issues is crucial for maintaining the credibility and fairness of academic publications.Originality/value:This study contributes to an understanding of critical issues within academic authorship,shedding light on the prevalence and impact of inappropriate authorship attributions.By calling for a nuanced approach to ensure accurate credit is given where it is due,the study underscores the importance of upholding ethical standards in scholarly publishing.展开更多
Tobacco is an illicit product sold in the world and involves fatal communicable diseases and deaths. In several countries, tobacco revenue contributes to the health of victims. This study aimed to evaluate the contrib...Tobacco is an illicit product sold in the world and involves fatal communicable diseases and deaths. In several countries, tobacco revenue contributes to the health of victims. This study aimed to evaluate the contribution of tobacco taxes to the financing of the health system in Democratic Republic of the Congo (DRC) during the period of 3 years (from 2019 to 2021) in order to give some suggestions. A descriptive literature review on the tobacco tax was conducted from three tobacco tax collection services: the services of the General Secretariat of Health in DRC (SGSH), the Program of the National Health Account (PNHA) and the General Direction of Customs and Assizes (GDCA). The analysis revealed that no retrocession and no activity covered by the tax collected on tobacco does not contribute to the financing of the health sector, in order to reduce the burden of households already impoverished by diseases caused by tobacco.展开更多
In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of enterprises.With systems spanning various sectors of enterprises geographically dispersed...In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of enterprises.With systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged significantly.The existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited devices.This study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side workload.Within this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and security.To curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution metric.Upon encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective defense.Experimental results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.展开更多
The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality product...The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality productivity,”defining it as an advanced form driven by innovation,embodying“high technology,efficiency,and quality,”with the aim of comprehensively enhancing productivity.It elucidates the necessity of cultivating such forces,asserting that they are crucial for achieving high-quality development,securing a leading position in global technology,and fulfilling the aspirations for a better life.Moreover,it outlines a new implementation route,emphasizing strategies such as fostering technological autonomy,nurturing emerging industries,integrating education and talent in technology,adopting a“build through challenges”approach,adjusting solutions locally,and providing categorized guidance,all of which are based on the ongoing comprehensive reforms.展开更多
For data mining tasks on large-scale data,feature selection is a pivotal stage that plays an important role in removing redundant or irrelevant features while improving classifier performance.Traditional wrapper featu...For data mining tasks on large-scale data,feature selection is a pivotal stage that plays an important role in removing redundant or irrelevant features while improving classifier performance.Traditional wrapper feature selection methodologies typically require extensive model training and evaluation,which cannot deliver desired outcomes within a reasonable computing time.In this paper,an innovative wrapper approach termed Contribution Tracking Feature Selection(CTFS)is proposed for feature selection of large-scale data,which can locate informative features without population-level evolution.In other words,fewer evaluations are needed for CTFS compared to other evolutionary methods.We initially introduce a refined sparse autoencoder to assess the prominence of each feature in the subsequent wrapper method.Subsequently,we utilize an enhanced wrapper feature selection technique that merges Mutual Information(MI)with individual feature contributions.Finally,a fine-tuning contribution tracking mechanism discerns informative features within the optimal feature subset,operating via a dominance accumulation mechanism.Experimental results for multiple classification performance metrics demonstrate that the proposed method effectively yields smaller feature subsets without degrading classification performance in an acceptable runtime compared to state-of-the-art algorithms across most large-scale benchmark datasets.展开更多
Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from Nov...Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology.展开更多
This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria hav...This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were recorded.Learning from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this study.To achieve the goal of this study,a combination of desktop research and survey design was employed.Questionnaires were administered to 390 respondents through a combination of stratified and random sampling techniques.The results of the survey were matched with that of the secondary data obtained through online websites and other related sources.The result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue State:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity building.However,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst others.To salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes amongst others.展开更多
The impacts of elevated atmospheric CO2 concentrations (500 靘olmol-1and 700 靘olmol-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to Oc...The impacts of elevated atmospheric CO2 concentrations (500 靘olmol-1and 700 靘olmol-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration of Pinus koraiensis seedlings were measured by a LI-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil in-stantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 靘olm 2s-1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively.展开更多
[Objective] The aim was to investigate the contribution of potassium,nitrogen and organic fertilizer to super rice production.[Method] The data about the labor force input,fertilizer input,organic fertilizer input,con...[Objective] The aim was to investigate the contribution of potassium,nitrogen and organic fertilizer to super rice production.[Method] The data about the labor force input,fertilizer input,organic fertilizer input,contents of effective nitrogen and effective potassium in production,obtained through empirical study of 690 rice farmers in eight counties (cities) in Liaoning,Zhejiang and Hunan in 2009,were analyzed by using Cobb-Douglas production function model to study influence of material input (especially the fertilizer input) and labor force input to the yield of super rice,and the correlation between the input and the yield of rice production.[Result] The increase in amount of organic fertilizer has significantly increased the yield of super rice.The amount of chemical fertilizer applied is becoming more reasonable,but increase of yield does not result in increase of value.Different types of fertilizers have significantly different capabilities in increasing yields of super rice.The potassium fertilizer is superior to phosphorous fertilizer,while phosphorous is superior to nitrogenous fertilizer in improving production capacity.[Conclusion] The paper suggests that it should continue to increase the amount of organic fertilizers and potassium fertilizer and meanwhile control the amount of nitrogenous fertilizer in super rice production at present.展开更多
基金supported by National Natural Science Foundation of China(Grant No.42361144888)Postdoctoral Fellowship Program of CPSF(Grant No.GZB20230060).
文摘There is less than half the time left to achieve the United Nations Sustainable Development Goals(SDGs),and progress toward SDGs is obviously insufficient.The contribution of ecosystem services(ES)to SDGs realization has received extensive attentions,but systematic generalization and recognition are still lacking.Based on a review of the progress and challenge of sustainable development,this study summarized ES’s potential contribution to 17 SDGs,and systematically reviewed empirical researches focused on the ES’s contribution to SDGs based on the RepOrting standards for Systematic Evidence Syntheses(ROSES).The results showed that from the 1960s to the 2020s,the ES’s contribution has gradually become more important in sustainable development.ES has potential contribution to all SDGs,but the contribution to different SDGs varies.In the empirical study,ES’s contribution to SDG2,SDG6,SDG13,and SDG15 were strongly focused.ES’s contribution to SDG4,SDG5,SDG10,SDG16,and SDG17 were weakly focused.Most researches have explored the ES’s contribution to SDGs based on ES supply at a single scale,lacking attentions to ES demand and scale differences,and insufficient attentions to intervention factors affecting the ES’s contribution to SDGs.Faced with the above deficiencies,future research could deepen the exploration of ES’s contribution to SDGs from the following four perspectives:clarifying true contributions,exploring leverage point,integrating multi-scale differences,and focusing on intervention factors.
基金supported by the National Natural Science Foundation of China(Nos.42075097 and 42177081)the National Key R&D Program of China(No.2023YFC3706103)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0760200)Beijing Municipal Natural Science Foundation(No.8222075)the Youth Cross Team Scientific Research Project of the Chinese Academy of Sciences(No.JCTD-2021-10)。
文摘During high-temperature periods in summer,formaldehyde(HCHO)levels increase due to secondary production.However,recent studies have also shown a rise in the HCHO concentration in winter,but the underlying cause remains unclear.Here,HCHO observations in urban Beijing were conducted,the impact of meteorological differences between warm and cold seasons to HCHO concentrations was investigated.Additionally,the positive matrix factorization model was applied to the source apportionment of HCHO,with a focus on changes during pollution events.The results indicated that,during warm seasons,the secondary production of HCHO was driven by high temperature influenced by the low-pressure front,with the contribution of secondary production+background peaking at 85.9% in the afternoon,exhibiting a unimodal diurnal variation.Conversely,during cold seasons,the influence of a uniform pressure field,coupled with weak winds,low boundary layers and high humidity,led to HCHO accumulation from primary emissions,resulting in multiday highconcentration pollution.During the most severe pollution periods,anthropogenic primary emissions contributed up to 91.7%.Therefore,while the contribution of volatile organic compounds to HCHO levels through secondary production has been recognized,the significant impact of primary emissions during cold seasons cannot be overlooked.
基金National Natural Science Foundation of China,No.42071415National Key Research and Development Program of China,No.2021YFE0106700Outstanding Youth Foundation of Henan Natural Science Foundation,No.202300410049。
文摘China is the world's largest carbon dioxide(CO_(2)) emitter and a major trading country. Both anthropogenic and natural factors play a critical role in its carbon budget. However,previous studies mostly focus on evaluating anthropogenic emissions or the natural carbon cycle separately, and few included trade-related(import and export) CO_(2) emissions and its contribution on global warming. Using the Carbon Tracker CT2019 assimilation dataset and China trade emissions from the Global Carbon Project, we found that the change trend of global CO_(2) flux had obvious spatial heterogeneity, which is mainly affected by anthropogenic CO_(2) flux. From 2000 to 2018, carbon emissions from fossil fuels in the world and in China all showed an obvious increasing trend, but the magnitude of the increase tended to slow down.In 2018, the radiative forcing(RF) caused by China's import and export trade was-0.0038 W m^(-2), and the RF caused by natural carbon budget was-0.0027 W m^(-2), offsetting 1.54% and 1.13% of the RF caused by fossil fuels that year, respectively. From 2000 to 2018, the contribution of China's carbon emission from fossil fuels to global RF was 11.32%. Considering China's import and export trade, the contribution of anthropogenic CO_(2) emission to global RF decreased to 9.50%. Furthermore, taking into account the offset of carbon sink from China's terrestrial ecosystems, the net contribution of China to global RF decreased to 7.63%. This study demonstrates that China's terrestrial ecosystem and import and export trade are all mitigating China's impact on global anthropogenic warming, and also confirms that during the research process on climate change, comprehensively considering the carbon budget from anthropogenic and natural carbon budgets is necessary to systematically understand the impacts of regional or national carbon budgets on global warming.
文摘The purpose of this paper is to identify the processes with the highest contribution to potential environmental impacts in the life cycle of the masonry of concrete blocks by evaluating their main emissions contributing to impact categories and identifying hotspots for environmental improvements.The research is based on the Life Cycle Assessment(LCA)study of non-load-bearing masonry of concrete blocks performed by the authors.The processes those have demonstrated higher contribution to environmental impacts were identified in the Life Cycle Impact Assessment(LCIA)phase and a detailed analysis was carried out on the main substances derived from these processes.The highest potential impacts in the life cycle of the concrete blocks masonry can be attributed mainly to emissions coming from the production of Portland cement,which explains the peak of impact potential on the blocks production stage,but also the significant impact potential in the use of the blocks for masonry construction,due to the use of cement mortar.The results of this LCA study are part of a major research on the comparative analysis of different typologies of non-load-bearing external walls,which aims to contribute to the creation of a life cycle database of major building systems,to be used by the environmental certification systems of buildings.
基金supported by the National Natural Science Foundation of China(No.52200120)the R&D Program of Beijing Municipal Education Commission(No.KM202310011003).
文摘CO_(2) emissions(CEs)pose a growing threat to environmental changes and global warming,attracting extensive attention.Here,we leveraged near-real-time monitoring data spanning 2019 to 2022 to investigate spatiotemporal heterogeneity,sectoral contributions,provincial spatial correlation,and driving factors influencing CEs at the provincial level in China.Our analysis,integrating Moran’s Index analysis,Spearman correlation analysis,and the Geographically Weighted Regression model,unveiled China’s consistent world-leading CEs,surpassing 10,000 Mt over the study period.Spatially,CEs exhibited a heterogeneous distribution,with markedly higher emissions in eastern and northern regions compared to western and southern areas.Temporally,CEs displayed significant fluctuations,peaking in the fourth quarter before declining in subsequent quarters.Chinese NewYear and COVID-19 had the biggest effects on CEs,with average daily reductions of-20.8%and-18.9%,respectively,compared to the four-year average and the same period in 2019.Sectoral analysis highlighted the power and industry sectors as primary contributors to CEs in China,jointly accounting for 37.9%-40.2%and 43.5%-46.4%of total CEs,respectively.Spatial clustering analysis identified a distinct High-High agglomeration region,predominantly encompassing provinces such as Inner Mongolia,Shandong and Jiangsu.Furthermore,total energy consumption and electricity consumption emerged as significant drivers of CEs,exhibiting correlation coefficients exceeding 0.9,followed by exhaust emissions,population size,and gross domestic product.Moreover,the influence of drivers on provincial CEs exhibited notable spatial heterogeneity,with regression coefficients displaying a decreasing gradient from north to south.These findings provide scientific and technological support to realize the provincial dual-carbon goals in China.
文摘A finite element and boundary element model of the 100 m X-BOW polar exploration cruise ship is established. The vibrated velocity-excited force admittance matrix is calculated by frequency response analysis, and the vibrated velocity in the stern plate and main engine foundations is tested during the trial trip. Then, the excited force of the propeller and main engine is derived using the vibrated velocity and admittance matrix.Based on the excited force, the cabin-simulated vibrated velocity is compared with the tested vibrated velocity, and the tolerance is within the allowable scope in engineering. Loading the excited forces on the boundary element model, the distribution characteristics of sound level underwater are analyzed. Then, forces excited by the main engine and propeller are loaded on the model, and the contribution ratio of excitation sources to underwater acoustic radiation is analyzed. The result provides a reference for vibration assessment in the early stage and control in the late stage.
基金supported by the National Key R&D Program of China(2017YFC1405005)the National Natural Science Foundation of China(71690233)
文摘The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio selection.Therefore,combining the system contribution rate with system portfolio selection is the focus of this study.It also focuses on calculating the contribution rates of multiple equipment systems with various types of capabilities.The contribution rate is measured by establishing a hierarchical multi-criteria value model from three dimensions.Based on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection strategy.Finally,an illustrative example is presented to verify the feasibility of the proposed model.
基金supported by the National Natural Science Foundation of China(71690233)the Scientific Research Foundation of National University of Defense Technology(ZK19-16)the PLA military graduate student funding project.
文摘Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimization of equipment architecture design,the adequate resources allocation,and the joint combat performance.From the system view,this paper proposes a method of weapons equipment portfolios selection(WEPS)based on the contribution rate of weapon systems,providing a new idea for weapon equipment portfolio selection.Firstly,we analyze the WEPS problem and the concept of the contribution rate under the systems background.Secondly,we propose a combat network modeling method for weapon equipment systems based on the function chain.Thirdly,we propose a WEPS method based on the contribution rate,fully considering the correlation relationships between potential weapons and the old weapon systems by the combat network model,under the limitation of capability demands and budget resources,with the objective to maximally increasing the combat ability of weapon systems.Finally,we make a case study with a specific WEPS problem where the whole calculation processes and results are analyzed and exhibited to verify the feasibility and effectiveness of the proposed method model.
基金supported by the National Key Research and Development Project(2018YFB1700802)the National Natural Science Foundation of China(72071206)the Science and Technology Innovation Plan of Hunan Province(2020RC4046).
文摘The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network.
基金The National Social Science Foundation Military Science Project(No.16GJ003-068).
文摘To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation process of the equipment SoS contribution rate were redefined and standardized.To solve the existing problems in the application of the original contribution rate formula,a modified contribution rate calculation formula is proposed.Finally,the contribution rate evaluation index was divided into latent and explicit variables.The measurement and structural equations in the SEM were used to calculate and analyze the latent variables.The simulation results show that the number of defense lines of air defense weapon equipment has a greater impact on the linear configuration than the group configuration.When the number of K-type air defense weapons is sufficient,the two-layer linear configuration should be adopted with 20 air defense weapon systems.When the number of K-type air defense weapons is insufficient,the single-layer group configuration should be adopted with 12 air defense weapon systems.
基金supported by the Chinese 973 program (Grant No.2013CB430104)the Chinese National Science Foundation (Grant Nos.41330421 and 41461164006)
文摘Central East China is an area where both intense hourly precipitation(IHP) events and mesoscale convection systems(MCSs) occur frequently in the warm seasons. Based on mosaics of composite Doppler radar reflectivity and hourly precipitation data during the warm seasons(May to September) from 1 July 2007 to 30 June 2011, the contribution of MCSs to IHP events exceeding 20 mm h^-1 over central East China was evaluated. An MCS was defined as a continuous or quasicontinuous band of 40d BZ reflectivity that extended for at least 100 km in at least one direction and lasted for at least 3h. It was found that the contribution of MCSs to IHP events was 45% on average over central East China. The largest contribution,more than 80%, was observed along the lower reaches of the Yellow River and in the Yangtze River–Huaihe River valleys.These regions were the source regions of MCSs, or along the frequent tracks of MCSs. There were two daily peaks in the numbers of IHP events: one in the late afternoon and one in the early morning. These peaks were more pronounced in July than in other months. MCSs contributed more to the early-morning IHP event peaks than to the late-afternoon peaks. The contributions of MCSs to IHP events with different intensities exhibited no significant difference, which fluctuated around 50% on average over central East China.
文摘Purpose:This study aims to evaluate the accuracy of authorship attributions in scientific publications,focusing on the fairness and precision of individual contributions within academic works.Design/methodology/approach:The study analyzes 81,823 publications from the journal PLOS ONE,covering the period from January 2018 to June 2023.It examines the authorship attributions within these publications to try and determine the prevalence of inappropriate authorship.It also investigates the demographic and professional profiles of affected authors,exploring trends and potential factors contributing to inaccuracies in authorship.Findings:Surprisingly,9.14%of articles feature at least one author with inappropriate authorship,affecting over 14,000 individuals(2.56%of the sample).Inappropriate authorship is more concentrated in Asia,Africa,and specific European countries like Italy.Established researchers with significant publication records and those affiliated with companies or nonprofits show higher instances of potential monetary authorship.Research limitations:Our findings are based on contributions as declared by the authors,which implies a degree of trust in their transparency.However,this reliance on self-reporting may introduce biases or inaccuracies into the dataset.Further research could employ additional verification methods to enhance the reliability of the findings.Practical implications:These findings have significant implications for journal publishers,Beyond authorship:Analyzing contributions in PLOS ONE and Maddi,A.,&the challenges of appropriate attribution highlighting the necessity for robust control mechanisms to ensure the integrity of authorship attributions.Moreover,researchers must exercise discernment in determining when to acknowledge a contributor and when to include them in the author list.Addressing these issues is crucial for maintaining the credibility and fairness of academic publications.Originality/value:This study contributes to an understanding of critical issues within academic authorship,shedding light on the prevalence and impact of inappropriate authorship attributions.By calling for a nuanced approach to ensure accurate credit is given where it is due,the study underscores the importance of upholding ethical standards in scholarly publishing.
文摘Tobacco is an illicit product sold in the world and involves fatal communicable diseases and deaths. In several countries, tobacco revenue contributes to the health of victims. This study aimed to evaluate the contribution of tobacco taxes to the financing of the health system in Democratic Republic of the Congo (DRC) during the period of 3 years (from 2019 to 2021) in order to give some suggestions. A descriptive literature review on the tobacco tax was conducted from three tobacco tax collection services: the services of the General Secretariat of Health in DRC (SGSH), the Program of the National Health Account (PNHA) and the General Direction of Customs and Assizes (GDCA). The analysis revealed that no retrocession and no activity covered by the tax collected on tobacco does not contribute to the financing of the health sector, in order to reduce the burden of households already impoverished by diseases caused by tobacco.
基金supported by the Project of National Natural Science Foundation of China under the grant titled“Research on Intermittent Fault Diagnosis of New Interconnection Networks under Comparative Model”(Approval Number:61862003).
文摘In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of enterprises.With systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged significantly.The existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited devices.This study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side workload.Within this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and security.To curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution metric.Upon encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective defense.Experimental results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.
基金The 2024 Chongqing Education Commission Humanities and Social Sciences Research Ideological and Political Education Special Project“Research on the Inner Logic and Practical Path of Empowering‘Digital Ideological and Political Education’with New Qualitative Productivity”(24SKSZ026)The 2024 Chongqing Education Commission Humanities and Social Sciences Research Ideological and Political Education Special Project“Research on the Value Connotation and Educational Path of‘Labor Innovation Collaboration’in Universities”(24SKSZ027)The 2023 Chongqing University of Posts and Telecommunications Education Reform Research Project“Innovation and Entrepreneurship Education Model Reform and Practice in New Engineering Talent Training:From the Perspective of the Second Classroom”(XJG23224)。
文摘The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality productivity,”defining it as an advanced form driven by innovation,embodying“high technology,efficiency,and quality,”with the aim of comprehensively enhancing productivity.It elucidates the necessity of cultivating such forces,asserting that they are crucial for achieving high-quality development,securing a leading position in global technology,and fulfilling the aspirations for a better life.Moreover,it outlines a new implementation route,emphasizing strategies such as fostering technological autonomy,nurturing emerging industries,integrating education and talent in technology,adopting a“build through challenges”approach,adjusting solutions locally,and providing categorized guidance,all of which are based on the ongoing comprehensive reforms.
基金supported in part by the National Key Research and Development Program of China under Grant(No.2021YFB3300900)the NSFC Key Supported Project of the Major Research Plan under Grant(No.92267206)+2 种基金the National Natural Science Foundation of China under Grant(Nos.72201052,62032013,62173076)the Fundamental Research Funds for the Central Universities under Grant(No.N2204017)the Fundamental Research Funds for State Key Laboratory of Synthetical Automation for Process Industries under Grant(No.2013ZCX11).
文摘For data mining tasks on large-scale data,feature selection is a pivotal stage that plays an important role in removing redundant or irrelevant features while improving classifier performance.Traditional wrapper feature selection methodologies typically require extensive model training and evaluation,which cannot deliver desired outcomes within a reasonable computing time.In this paper,an innovative wrapper approach termed Contribution Tracking Feature Selection(CTFS)is proposed for feature selection of large-scale data,which can locate informative features without population-level evolution.In other words,fewer evaluations are needed for CTFS compared to other evolutionary methods.We initially introduce a refined sparse autoencoder to assess the prominence of each feature in the subsequent wrapper method.Subsequently,we utilize an enhanced wrapper feature selection technique that merges Mutual Information(MI)with individual feature contributions.Finally,a fine-tuning contribution tracking mechanism discerns informative features within the optimal feature subset,operating via a dominance accumulation mechanism.Experimental results for multiple classification performance metrics demonstrate that the proposed method effectively yields smaller feature subsets without degrading classification performance in an acceptable runtime compared to state-of-the-art algorithms across most large-scale benchmark datasets.
文摘Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology.
文摘This study analysed the socio-economic contributions of N-Power programme amongst the beneficiaries of the scheme in Benue State.Prior to the introduction of N-Power programme,successive administrations in Nigeria have made concerted efforts towards improving the standard of living of the citizenry through the execution of various welfare or social intervention programmes,but not much successes were recorded.Learning from the mistakes of the past regimes,and by way of deliberate state policy,the Buhari’s government initiated a multi-pronged social investment policy,one of which is the N-power programme that came onboard in 2016,which also doubles as the subject of this study.To achieve the goal of this study,a combination of desktop research and survey design was employed.Questionnaires were administered to 390 respondents through a combination of stratified and random sampling techniques.The results of the survey were matched with that of the secondary data obtained through online websites and other related sources.The result indicated that N-Power made positive contributions to the socio-economic life of the beneficiaries in Benue State:specifically,the scheme contributed in poverty eradication,employment generation,skills acquisitions and capacity building.However,some aspect of our findings revealed that the programme has a number of challenges such as:inadequate cash support,delay in monthly cash transfer to beneficiaries,distance participants had to move to their work stations,absence of posting in N-Teach scheme,and lack of adequate working tools amongst others.To salvage this problem the paper recommended the following solutions:expansion of the scheme to cover N-Teach and other aspects,increment in the monthly cash transfer to cushion the high rate of inflation,support for the participants/beneficiaries in transportation and logistics,enrolment of more youth into the various schemes,proper monitoring and evaluation of the implementation of the schemes amongst others.
文摘The impacts of elevated atmospheric CO2 concentrations (500 靘olmol-1and 700 靘olmol-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration of Pinus koraiensis seedlings were measured by a LI-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil in-stantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 靘olm 2s-1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively.
文摘[Objective] The aim was to investigate the contribution of potassium,nitrogen and organic fertilizer to super rice production.[Method] The data about the labor force input,fertilizer input,organic fertilizer input,contents of effective nitrogen and effective potassium in production,obtained through empirical study of 690 rice farmers in eight counties (cities) in Liaoning,Zhejiang and Hunan in 2009,were analyzed by using Cobb-Douglas production function model to study influence of material input (especially the fertilizer input) and labor force input to the yield of super rice,and the correlation between the input and the yield of rice production.[Result] The increase in amount of organic fertilizer has significantly increased the yield of super rice.The amount of chemical fertilizer applied is becoming more reasonable,but increase of yield does not result in increase of value.Different types of fertilizers have significantly different capabilities in increasing yields of super rice.The potassium fertilizer is superior to phosphorous fertilizer,while phosphorous is superior to nitrogenous fertilizer in improving production capacity.[Conclusion] The paper suggests that it should continue to increase the amount of organic fertilizers and potassium fertilizer and meanwhile control the amount of nitrogenous fertilizer in super rice production at present.