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Pumping-induced Well Hydraulics and Groundwater Budget in a Leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties
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作者 ZHUANG Chao LÜChenyang +5 位作者 YAN Long LI Yabing ZHOU Zhifang WANG Jinguo DOU Zhi Walter A.ILLMAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期477-490,共14页
In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is... In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical analysis.Analytical investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard depletion.Locations of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater budget.In the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer drawdown.When using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage. 展开更多
关键词 HYDROGEOLOGY AQUITARD vertical heterogeneity semi-analytical solution well hydraulics groundwater budget
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Link Budget and Enhanced Communication Distance for Ambient Internet of Things
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作者 YANG Yibing LIU Ming +2 位作者 XU Rongtao WANG Gongpu GONG Wei 《ZTE Communications》 2024年第1期16-23,共8页
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t... Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m. 展开更多
关键词 ambient IoT(AIoT) B5G backscatter communication link budget low-noise amplifier(LNA) Release 19 tag chip sensitivity upper bounds
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Discussion on Construction Project Cost Budget Settlement Review
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作者 Hongfeng Liu Yumin Yuan 《Journal of Architectural Research and Development》 2024年第1期43-48,共6页
Construction project cost control involves many complex contents,forming a large amount of data information.If the processing method is unreasonable,it will likely affect the cost control efficiency.Therefore,in the c... Construction project cost control involves many complex contents,forming a large amount of data information.If the processing method is unreasonable,it will likely affect the cost control efficiency.Therefore,in the current construction project management,the review of project cost budget settlement is the focus to solve the cost management problems of construction projects and promote the development of the construction industry.This article mainly analyzes the influencing factors and current situation of construction project cost budget settlement review,and based on this,it explores the project cost budget settlement review strategy to promote the healthy development of construction project cost work. 展开更多
关键词 Construction project COST budget settlement Review strategy
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Analysis of Hospital Budget Management Control Based on Smart Hospital
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作者 Yuqi Chen 《Journal of Clinical and Nursing Research》 2024年第5期169-173,共5页
Hospitals are crucial healthcare facilities where patients seek treatment,and effective budget management within hospitals significantly impacts their operational efficiency and financial performance.In the age of inf... Hospitals are crucial healthcare facilities where patients seek treatment,and effective budget management within hospitals significantly impacts their operational efficiency and financial performance.In the age of information technology and advanced healthcare solutions,the emergence of smart hospitals represents a new trend in the medical industry’s evolution.Leveraging modern information technology can enhance the development of hospital IT systems and drive budget management toward greater intelligence.This paper begins by analyzing the influence of smart hospitals on hospital budget control.It then examines the current state of budget management control within smart hospitals.Finally,it proposes several strategies for budget management control in smart hospitals,aiming to provide guidance for relevant stakeholders. 展开更多
关键词 Smart hospital Hospital management budget management Financial control Control strategies
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Household behavior in practicing mental budgeting based on the theory of planned behavior 被引量:1
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作者 Ume Habibah Ibne Hassan +1 位作者 Muhammad Shahid Iqbal Naintara 《Financial Innovation》 2018年第1期408-421,共14页
Ajzen’s theory of planned behavior(TPB)suggests that planned behavior is determined by behavioral intention.Despite extensive literature based on TPB,household mental budgeting behavior explained by TPB is underexplo... Ajzen’s theory of planned behavior(TPB)suggests that planned behavior is determined by behavioral intention.Despite extensive literature based on TPB,household mental budgeting behavior explained by TPB is underexplored.The current study empirically tested TPB factors in light of mental budgeting behavior.The hypothesized model was tested using partial least squares structural equation modeling(PLS-SEM).PLS-SEM was employed using a Likert-scaled questionnaire administered to 275 households.The results indicate that mental budgeting attitude and mental budgeting past behavior strongly predict mental budgeting intention,and mental budgeting intention predicts mental budgeting behavior.Further,mental budgeting intention partially mediates the relationship between mental budgeting attitude and mental budgeting behavior,and mental budgeting past behavior and mental budgeting behavior.This study contributes to the academic interest in theoretical progress in household behavior. 展开更多
关键词 Mental budgeting behavior Household budgeting behavior Mental budgeting attitude Mental budgeting past behavior Mental budgeting intention
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Effective Budgetary Control System:A Regression Model for Indian Listed Companies
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作者 Alireza Kaab K.Manoharan Nair 《Journal of Modern Accounting and Auditing》 2021年第1期41-51,共11页
Budgetary control system is a sin quo non for every business irrespective of whether it is small,medium or large.It is used for forecasting,fixing the responsibility of the departments,and the effective utilization of... Budgetary control system is a sin quo non for every business irrespective of whether it is small,medium or large.It is used for forecasting,fixing the responsibility of the departments,and the effective utilization of resources.It in turn leads to increase in the productivity,profitability and return on investment.Budgetary control system helps the senior managers to ensure that spending limits are adequate.Budgetary control system becomes one of the most vital and critical area of business management.Presently,much attention has been given to improving of budgetary control and planning and their interrelationship in developing countries including India.Two-way analysis is made in this paper:One is developing predictor model for an effective budgetary control system for listed companies in India and the other is the analysis on the quality reporting system for financial statements especially budgetary control system.The method of research is empirical which tests the feasibility of solution using empirical evidences based on the statistical applications.The result of the current study shows that effective budgetary control factors are prominent in determining the budgetary control system in Indian listed companies and have significant correlation between dependent and independent variables.The study suggested initiating steps for using budget as a tool for optimum use of available resources,for avoiding conflicts among departments while allocation of resources and for increasing the inspirational quality of the budget for budgetary control. 展开更多
关键词 budgetary control system effective budgetary control factors Indian listed companies traditional budgeting budget related targets budgetING management accounting Introduction
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Incentive-compatible and budget balanced AGV mechanism for peer-to-peer energy trading in smart grids 被引量:1
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作者 Yujia Chen Wei Pei +1 位作者 Hao Xiao Tengfei Ma 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期26-35,共10页
Peer-to-peer(P2P)energy trading refers to a type of decentralized transaction,where the energy from distributed energy resources is directly traded between peers.A key challenge in peer-to-peer energy trading is desig... Peer-to-peer(P2P)energy trading refers to a type of decentralized transaction,where the energy from distributed energy resources is directly traded between peers.A key challenge in peer-to-peer energy trading is designing a safe,efficient,and transparent trading model and operating mechanism.In this study,we consider a P2P trading environment based on blockchain technology,where prosumers can submit bids or offers without knowing the reports of others.We propose an Arrow-d’Aspremont-Gerard-Varet(AGV)-based mechanism to encourage prosumers to submit their real reserve price and determine the P2P transaction price.We demonstrate that the AGV mechanism can achieve Bayesian incentive compatibility and budget balance.Kernel density estimation(KDE)is used to derive the prior distribution from the historical bid/offer information of the agents.Case studies are carried out to analyze and evaluate the proposed mechanism.Simulation results verify the effectiveness of the proposed mechanism in guiding agents to report the true reserve price while maximizing social welfare.Moreover,we discuss the advantages of budget balance for decentralized trading by comparing the Vickrey-Clarke-Groves(VCG)and AGV mechanisms. 展开更多
关键词 P2P energy trading AGV mechanism budget balance Incentive compatibility
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Kinetic Energy Budgets during the Rapid Intensification of Typhoon Rammasun (2014)
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作者 Xin QUAN Xiaofan LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期78-94,共17页
In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the ... In this study,Typhoon Rammasun(2014)was simulated using the Weather Research and Forecasting model to examine the kinetic energy during rapid intensification(RI).Budget analyses revealed that in the inner area of the typhoon,the conversion from symmetric divergent kinetic energy associated with the collocation of strong cyclonic circulation and inward flow led to an increase in the symmetric rotational kinetic energy in the lower troposphere.The increase in the symmetric rotational kinetic energy in the mid and upper troposphere resulted from the upward transport of symmetric rotational kinetic energy from the lower troposphere.In the outer area,both typhoon and Earth’s rotation played equally important roles in the conversion from symmetric divergent kinetic energy to symmetric rotational kinetic energy in the lower troposphere.The decrease in the symmetric rotational kinetic energy in the upper troposphere was caused by the conversion to asymmetric rotational kinetic energy through the collocation of symmetric tangential rotational winds and the radial advection of asymmetric tangential rotational winds by radial environmental winds. 展开更多
关键词 Typhoon Rammasun(2014) rapid intensification kinetic energy budget symmetric and asymmetric winds divergent and rotational circulations environmental flows
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Pointing Fingers from A Glass House The fundamental purpose of the increase in China’s defense budget is to safeguard national security and meet the challenges of global changes unseen in a century
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作者 Wang Keyu 《China Report ASEAN》 2023年第4期32-33,共2页
On March 5,the Ministry of Finance released the 2023 government budget draft report,according to which China’s defense budget of 2023 will be 1.55 trillion yuan(US$224.79 billion),an increase of 7.2 percent year on y... On March 5,the Ministry of Finance released the 2023 government budget draft report,according to which China’s defense budget of 2023 will be 1.55 trillion yuan(US$224.79 billion),an increase of 7.2 percent year on year,which is only 0.1 percentage points higher than 2022.The release of the defense budget attracted the attention of many foreign media outlets,some of which delivered distorted interpretations and exaggerated“China’s threat of force.”On March 6,Tan Kefei,spokesperson for the delegation of the People’s Liberation Army and the People’s Armed Police Force to the First Session of the 14th National People’s Congress,said that China has adhered to the principle of coordinated development of national defense and economic development. 展开更多
关键词 budget delegation outlet
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The Role of Legislators and Budget Process in Nigeria
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作者 Imuetinyan Eguavoen Isaac Ukarin Peter Oghenebrozie Avinyeze 《Macro Management & Public Policies》 2022年第3期1-6,共6页
This study examined the role of the legislators and budget process in Nigeria.For the objective of the study to be achieved,the study embraces the library research which involves a review of extant literature and this... This study examined the role of the legislators and budget process in Nigeria.For the objective of the study to be achieved,the study embraces the library research which involves a review of extant literature and this forms the basis for drawing up the conclusion.Flowing from the review,the study shows that argument has been raised by several analysts that legislative oversight committees have found not to be very effective in stimulating Ministries,Departments and Agencies(MDAs)for budget outcomes attainment.The argument is that oversight activities are used by some legislative committees to intimidate rather than encouraging(MDAs)to perform at the optimum levels especially in the areas of budget implementation.The study therefore recommends that the legislators in the Nigeria budget process should ensure that the MDAs make proper use of the funds allocated to them efficiently and effectively with a view to preventing careless spending,diversion as well as the misappropriation of public funds.The oversight activities of the legislative committees should be used to encourage MDAs to perform at the optimum levels especially in the areas of budget implementation and not to intimidate. 展开更多
关键词 budget budget implementation budget process LEGISLATURE NIGERIA
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用Budget方法评估食品防腐剂摄入量 被引量:1
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作者 裴世春 张东杰 +1 位作者 程远 曹静晶 《粮油食品科技》 2006年第4期42-44,共3页
分析了在Codex为了设定食品添加剂的使用标准而被应用的Budget方法论,并提出了适用于中国人饮食情况的使用准则。在此基础上对苯甲酸及其钠盐、山梨酸及其钾盐、对羟基苯甲酸乙脂和双乙酸钠的国内理论最大摄入量进行了估算。其结果苯甲... 分析了在Codex为了设定食品添加剂的使用标准而被应用的Budget方法论,并提出了适用于中国人饮食情况的使用准则。在此基础上对苯甲酸及其钠盐、山梨酸及其钾盐、对羟基苯甲酸乙脂和双乙酸钠的国内理论最大摄入量进行了估算。其结果苯甲酸及其钠盐、对羟基苯甲酸乙脂、双乙酸钠的每日最大理论摄入量超过了ADI(acceptable daily intakes)值,而山梨酸及其钾盐的每日最大理论摄入量估算值低于ADI值,因此即使在允许使用的所有食品群里以目前使用标准使用山梨酸及其钾盐也不会造成危害。 展开更多
关键词 budget方法 食品防腐剂 风险评估 摄入量
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A Brief Discussion on the Comprehensive Budget of Industrial Enterprises
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作者 Chaocui Wang 《Journal of Finance Research》 2017年第1期45-51,共7页
The medium-sized industrial enterprise is the important component of our national economy, its development is fine or not, representing the rise and decline of our national economy, the research focal point of standar... The medium-sized industrial enterprise is the important component of our national economy, its development is fine or not, representing the rise and decline of our national economy, the research focal point of standard lies in what utilizes the west to manage in the theory budgets for the financial administration which strengthens enterprises in The Master Budgeting. This text introduces relevant contents of master budgeting, analyze the difficult problem met in implementing, and combine enterprise's own characteristics to solve. First of all, this kind of enterprise of our country is a kind of enterprise surviving between grouping enterprise and small business, it indicates, there is this kind of enterprise to the demand for development of big enterprise by own enterprise characteristic. Utilize the budgets of enterprises to manage and strengthen management to the budgets of enterprises, introduce, direct against the question that the characteristic of every enterprise uses enterprise's budget management and should be paid attention to. 展开更多
关键词 The MASTER budgetING Medium-Sized industrial ENTERPRISE The MASTER budget for and MANAGE
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Nutrient Budget and Soil Nutrient Status in Greenhouse System 被引量:29
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作者 YU Hai-ying LI Ting-xuan ZHANG Xi-zhou 《Agricultural Sciences in China》 CSCD 2010年第6期871-879,共9页
This paper is based on nutrient budget and its effects on soil nutrient status in typical greenhouse system in China to provide a basis for raising the utilization rate of fertilizers and maintaining the sustainable d... This paper is based on nutrient budget and its effects on soil nutrient status in typical greenhouse system in China to provide a basis for raising the utilization rate of fertilizers and maintaining the sustainable development of agriculture in the greenhouse.By investigating the management of 18 representative greenhouses in Shouguang,Shandong Province,China,and analyzing both the greenhouse and open field soil samples,the soil nutrient budget and the trend of nutrient accumulation and translocation in soils were thus studied.The results under greenhouse system showed that the average annual inputs of N,P2O5 and K2O were 4 088,3 655 and 3 437 kg ha-1,respectively.The total inputs of N,P2O5 and K2O provided by chemical fertilizers which are the main source of soil nutrient were 63,61 and 66%,respectively.The utilization rates of N,P2O5 and K2O were only 24,8,46% and the input ratio among N,P2O5 and K2O (1:0.9:0.8) was quite different from the uptake ratio (1:0.3:1.4).It had caused the excess of N,P2O5 and K2O in the soil,and the theoretical surpluses were 3 214,3 401 and 2 322 kg ha-1,respectively,for N,P2O5 and K2O.The level of the organic matter,total nitrogen,nitrate nitrogen,available phosphorus,and available potassium was increased substantially,and their maximum level was observed in the topsoil (0-20 cm) with an average value being 1.4,1.9,21.2,5.4,and 3.7 times higher than that of the open field soil,respectively.The greenhouse soils showed leaching of the nutrients,especially NO3- which would cause a potential risk to the quality of groundwater in the area.It is necessary to apply more organic manure and provide nutrients according to the crop requirements and soil fertility as it could not only produce high crop yield,but also be beneficial to balance the soil nutrient and improve the utilization rate of fertilizers.Further,there would be no significant surplus of nutrients which may leach out of soil to contaminate the environment. 展开更多
关键词 greenhouse system FERTILIZATION nutrient budget soil nutrient status
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Atmospheric hydrological budget with its effects over Tibetan Plateau 被引量:12
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作者 BAIJingyu XUXiangde 《Journal of Geographical Sciences》 SCIE CSCD 2004年第1期81-86,共6页
Based on 1961-2000 NCEP/NCAR monthly mean reanalysis datasets, vapor transfer and hydrological budget over the Tibetan Plateau are investigated. The Plateau is a vapor sink all the year round. In summer, ... Based on 1961-2000 NCEP/NCAR monthly mean reanalysis datasets, vapor transfer and hydrological budget over the Tibetan Plateau are investigated. The Plateau is a vapor sink all the year round. In summer, vapor is convergent in lower levels (from surface to 500 hPa) and divergent in upper levels (from 400 to 300 hPa), with 450 hPa referred to as level of non-divergence. Two levels have different hydrologic budget signatures: the budget is negative at the upper levels from February to November, i.e., vapor transfers from the upper levels over the plateau; as to the lower, the negative (positive) budget occurs during the winter (summer) half year. Evidence also indicates that Tibetan Plateau is a 'vapor transition belt', vapor from the south and the west is transferred from lower to upper levels there in summer, which will affect surrounding regions, including eastern China, especially, the middle and lower reaches of the Yangtze. Vapor transfer exerts significant influence on precipitation in summertime months. Vapor transferred from the upper layers helps humidify eastern China, with coefficient -0.3 of the upper budget to the precipitation over the middle and lower reaches of the Yangtze (MLRY); also, vapor transferred from east side (27.5 o -32.5 o N) of the upper level has remarkable relationship with precipitation, the coefficient being 0.41. The convergence of the lower level vapor has great effects on the local precipitation over the plateau, with coefficient reaching 0.44, and the vapor passage affects the advance and retreat of the rainbelt. In general, atmospheric hydrologic budget and vapor transfer over the plateau have noticeable effects on precipitation of the target region as well as the ambient areas. 展开更多
关键词 Tibetan Plateau atmospheric hydrologic budget vapor transfer RAINFALL
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On the Upper Oceanic Heat Budget in the South China Sea:Annual Cycle 被引量:9
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作者 杨海军 刘秦玉 贾旭晶 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第4期619-629,共11页
The upper oceanic heat budget in the South China Sea (SCS) is studied on the basis of ocean surface heat flux, upper sea heat storage and horizontal oceanic heat transport calculated from Comprehensive Ocean and Atmos... The upper oceanic heat budget in the South China Sea (SCS) is studied on the basis of ocean surface heat flux, upper sea heat storage and horizontal oceanic heat transport calculated from Comprehensive Ocean and Atmosphere Data Set. Several useful conclusions can be obtained and they are helpful for us to understand the climatologically thermal condition in the SCS. The annual variation of net heat budget reflects the adjustment and sudden change of the monsoon circulation over the SCS. The variation of upper oceanic heat storage of the SCS is tightly connected with the oceanic heat transport as well as the vertical movement in the SCS and so on. 展开更多
关键词 South China Sea Heat flux Heat storage Net heat budget
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Response of soil Olsen-P to P budget under different long-term fertilization treatments in a fluvo-aquic soil 被引量:7
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作者 ZHANG Wei-wei ZHAN Xiao-ying +2 位作者 ZHANG Shu-xiang Khalid Hamdan Mohamed Ibrahima XU Ming-gang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第3期667-676,共10页
The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P a... The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg^(–1) for every 100 kg ha^(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha^(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg^(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha^(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha^(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg^(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha^(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha^(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased and that of summer maize could be decreased based on the results of treatments in chemical fertilization. Additionally, when chemical fertilizers are combined with manures(NPKM and 1.5 NPKM), it could take approximately 9–11 years for soil Olsen-P to decrease to the critical soil P values of crops grown in the absence of P fertilizer. 展开更多
关键词 long-term FERTILIZATION fluvo-aquic SOIL OLSEN-P P budget critical SOIL P value
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A Study on Water Vapor Transport and Budget of Heavy Rain in Northeast China 被引量:7
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作者 孙力 沈柏竹 隋波 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第6期1399-1414,共16页
The characteristics of moisture transport and budget of widespread heavy rain and local heavy rain events in Northeast China are studied using the NCEP-NCAR reanalysis 6-hourly and daily data and daily precipitation d... The characteristics of moisture transport and budget of widespread heavy rain and local heavy rain events in Northeast China are studied using the NCEP-NCAR reanalysis 6-hourly and daily data and daily precipitation data of 200 stations in Northeast China from 1961-2005. The results demonstrate that during periods with widespread heavy rain in Northeast China, the Asian monsoon is very active and the monsoonal northward moisture transport is strengthened significantly. The widespread heavy rainfall obtains enhanced water vapor supply from large regions where the water vapor mainly originates from the Asian monsoon areas, which include the East Asian subtropical monsoon area, the South China Sea, and the southeast and southwest tropical monsoon regions. There are several branches of monsoonal moisture current converging on East China and its coastal areas, where they are strengthened and then continue northward into Northeast China. Thus, the enhanced northward monsoonal moisture transport is the key to the widespread heavy rain in Northeast China. In contrast, local heavy rainfall in Northeast China derives water vapor from limited areas, transported by the westerlies. Local evaporation also plays an important role in the water vapor supply and local recycling process of moisture. In short, the widespread heavy rains of Northeast China are mainly caused by water vapor advection brought by the Asian monsoon, whereas local heavy rainfall is mainly caused by the convergence of the westerly wind field. 展开更多
关键词 heavy rain Northeast China moisture transport moisture budget Asian monsoon
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Surface Heat Budget and Solar Radiation Allocation at a Melt Pond During Summer in the Central Arctic Ocean 被引量:5
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作者 ZHANG Shugang ZHAO Jinping +1 位作者 SHI Jiuxin JIAO Yutian 《Journal of Ocean University of China》 SCIE CAS 2014年第1期45-50,共6页
The heat budget of a melt pond surface and the solar radiation allocation at the melt pond are studied using the 2010 Chinese National Arctic Research Expedition data collected in the central Arctic. Temperature at a ... The heat budget of a melt pond surface and the solar radiation allocation at the melt pond are studied using the 2010 Chinese National Arctic Research Expedition data collected in the central Arctic. Temperature at a melt pond surface is proportional to the air temperature above it. However, the linear relationship between the two varies, depending on whether the air temperature is higher or lower than 0℃. The melt pond surface temperature is strongly influenced by the air temperature when the latter is lower than 0℃. Both net longwave radiation and turbulent heat flux can cause energy loss in a melt pond, but the loss by the latter is larger than that by the former. The turbulent heat flux is more than twice the net longwave radiation when the air temperature is lower than 0℃. More than 50% of the radiation energy entering the pond surface is absorbed by pond water. Very thin ice sheet on the pond surface(black ice) appears when the air temperature is lower than 0℃; on the other hand, only a small percentage(5.5%) of net longwave in the solar radiation is absorbed by such a thin ice sheet. 展开更多
关键词 heat budget MELT POND solar radiation ARCTIC
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A Study of Influencing Systems and Moisture Budget in a Heavy Rainfall in Low Latitude Plateau in China during Early Summer 被引量:7
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作者 董海萍 赵思雄 曾庆存 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第3期485-502,共18页
Analysis of a heavy rainfall in a lower latitude plateau and characteristics of water vapor transportation have been conducted by using conventional data and denser surface data. The results show: (1) the heavy rai... Analysis of a heavy rainfall in a lower latitude plateau and characteristics of water vapor transportation have been conducted by using conventional data and denser surface data. The results show: (1) the heavy rainfall was caused by a series of mesoscale systems under favorable large-scale conditions when the warm moister air and cold air interacted with each other. At the same time, the coupling between the upper- and lower-level jets was revealed. It is also found that there exists some different characteristics among the main influencing systems of heavy rainfalls in Yunnan, such as the Indian-Myanmar trough and the path of the cold air, compared with those in East and South China. (2) The interaction between mesoscale convergence lines near the ground may be a possible triggering mechanism for the occurrence of mesoscale systems, and the dynamical and thermal dynamical structure of the mesoscale systems was very obvious. The convergence lines may relate closely to the terrain of Yunnan, China. (3) The computation of the water vapor budget reveals that the primary source of water vapor supply for heavy rainfall was in the Bay of Bengal. In this case, the water vapor could be transported into Yunnan even though the amount of water vapor was less than that in the lower troposphere in East and South China. In addition, the analysis for three-dimensional air parcel trajectories better revealed and described the source location and the transportation of water vapor to Yunnan. 展开更多
关键词 heavy rainfall mesoscale systems moisture budget Yunnan-Guizhou Plateau
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Vorticity Budget Investigation of a Simulated Long-Lived Mesoscale Vortex in South China 被引量:8
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作者 陈敏 郑永光 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第6期928-940,共13页
A vorticity budget investigation is performed using the output data from a numerical simulation of a typical MCV (mesoscale convectively generated votex) case in South China. Results suggest that the divergence caus... A vorticity budget investigation is performed using the output data from a numerical simulation of a typical MCV (mesoscale convectively generated votex) case in South China. Results suggest that the divergence caused by convection in the low troposphere is the main producer of positive vorticity, while vertical vorticity transferred by the tilting term from the horizontal vorticity compensates the upward output of cyclonic vorticity. Scale analyses of the vorticity equation suggest that the advection of planetary vorticity can be neglected owing to the low latitude, which is di?erent from the larger scale systems in high latitude areas. In addition, the distribution of relative vorticity tendency on pressure level is not uniform. A vortex will move along the vector from the negative to the positive vorticity tendency region. The mechanism of the phenomenon—that nearly all of the convectively ascending region is located southward/southeastward of the vortex center—is also discussed. Convergence with regard to latent heat release would be in favor of the spin-up of meso-vortex, however, the horizontal vorticity caused by wind shear is tilted by vertical motion due to convection. Consequently, the negative and positive vorticity tendencies are located symmetrically about the convective center, which suggests that the vortex southward movement is dynamically driven by convection. 展开更多
关键词 Vorticity budget mesoscale convectively generated votex mesoscale convective system
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