Water Vapor,Cloud,and Surface Rainfall Budgets Associated with the Landfall of Typhoon Krosa(2007):A Two-Dimensional Cloud-Resolving Modeling Study

Water vapor, cloud, and surface rainfall budgets associated with the landfall of Typhoon Krosa on 6-8 October 2007 are analyzed based on a two-dimensional cloud-resolving model simulation. The model is integrated with imposed zonally-uniform vertical velocity, zonal wind, horizontal temperature, and vapor advection from NCEP/Global Data Assimilation System （GDAS） data. The simulation data that are validated with observations are examined to study physical causes associated with surface rainfall processes during the landfall. The time- and domain-mean analysis shows that when Krosa approached the eastern coast of China on 6 October, the water vapor convergence over land caused a local atmospheric moistening and a net condensation that further produced surface rainfall and an increase of cloud hydrometeor concentration. Meanwhile, latent heating was balanced by advective cooling and a local atmospheric warming. One day later, the enhancement of net condensation led to an increase of surface rainfall and a local atmospheric drying, while the water vapor convergence weakened as a result of the landfall-induced deprivation of water vapor flux. At the same time, the latent heating is mainly compensated the advective cooling. Further weakening of vapor convergence on 8 October enhanced the local atmospheric drying while the net condensation and associated surface rainfall was maintained. The latent heating is balanced by advective cooling and a local atmospheric cooling.

Sensitivity analysis of the De Nitrification and De Composition model for simulating regional carbon budget at the wetlandgrassland area on the Zoige Plateau,China

Although mathematical models(e.g., De Nitrification and De Composition(DNDC) provide a powerful tool to study regional carbon budget, it is still difficult to obtain accurate simulation results because there exists large uncertainties in modeling regional carbon budget. Through the investigation on the sensitivity of model output parameters to the input parameters, sensitivity analysis(SA) has been proved to be able to identify the key sources of uncertainties and be helpful to reduce the model uncertainties. However, some input parameters with discrete values(e.g., land use type and soil type) and the regional effect of the sensitive parameters were rarely examined in SA. In this paper, taking the Zoige Plateau as a case area, we combined the one-factor-ata-time(OAT) with Extended Fourier Amplitude Sensitivity Test(EFAST) to conduct a SA of DNDC for simulating the regional carbon budget, including Gross Primary Productivity(GPP), Net Primary Productivity(NPP), Net Ecosystem Productivity(NEP), autotrophic respiration(Ra), soil microbial heterotrophic respiration(Rh) and ecosystem respiration(Re). The result showed that the combination of OAT and EFAST could test the contribution of the input parameters with discrete values to the output parameters. In DNDC model, land use type and soil type had a significant impact on the regional carbon budget of the Zoige Plateau, and daily temperature was also confirmed to be one of the most important parameters for carbon budget. For the other input parameters, with the change of land use type or soil type at regional scale, the sensitive parameters of carbon budget would vary accordingly. The SA results would provide scientific evidence to optimize DNDC model and they suggested that we should pay attention to the spatial/temporal effect of SA and try to use the appropriate data in simulation of the regional carbon budget.

Modeling the Impact of Land-Use Change on Water Budget of Gaza Strip

Gaza has a water crisis and faces serious challenges for the future sustainability of its water resources. Land-use change has an expected effect on water budget of the Gaza Strip. Three different land cover scenarios;the and cover of 2007, land cover of 2020, and full urbanization land cover were simulated independently using The Automated Geospatial Watershed Assessment (AGWA) tool which work under the umbrella of GIS. In general, the simulation results indicate that land-cover changes will significantly alter the hydrologic response of Gaza region. Percolation is expected to decrease in all options as urban areas are expanded where as the simulated surface runoff reflected a relative departure from the first scenario comparing with other scenarios. In the baseline scenario (2007), the simulated surface runoff and percolation represent 12% and 41% respectively from the water budget components of the Gaza Strip. In year 2020, these values were expected by the simulation results to be 20% and 27% respectively. A unique linear relationship between the relative change in urban area and the corresponding relative change in surface water has been investigated from the simulation results. The analysis of the three urbanization scenarios can give decision makers better understand for the future situation and assist them to advance towards achieving sustainable development planning for water resources system in the Gaza Strip.

Case Analyses and Numerical Simulation of Soil ThermalImpacts on Land Surface Energy Budget Based on anOff-Line Land Surface Model

The statistical relationship between soil thermal anomaly and short-term climate change is presented based on a typical case study. Furthermore, possible physical mechanisms behind the relationship are re-vealed through using an off-line land surface model with a reasonable soil thermal forcing at the bottom of the soil layer. In the first experiment, the given heat flux is 5 W m2 at the bottom of the soil layer (in depth of 6.3 m) for 3 months, while only a positive ground temperature anomaly of 0.06°C can be found compared to the control run. The anomaly, however, could reach 0.65°C if the soil thermal conductivity was one order of magnitude larger. It could be even as large as 0.81°C assuming the heat flux at bottom is 10 W m-2. Mean-while, an increase of about 10 W m−2 was detected both for heat flux in soil and sensible heat on land sur-face, which is not neglectable to the short-term climate change. The results show that considerable response in land surface energy budget could be expected when the soil thermal forcing reaches a certain spatial-tem-poral scale. Therefore, land surface models should not ignore the upward heat flux from the bottom of the soil layer. Moreover, integration for a longer period of time and coupled land-atmosphere model are also necessary for the better understanding of this issue.

市场渗透率约束下的拼车奖励方案优化模型

目前,我国拼车出行交通模式的市场份额相对较低,在缓解交通拥堵、节能减排方面仍有巨大潜力未被充分挖掘。基于奖励的交通需求管理策略可以提高民众拼车出行意愿,但奖励方案的设置与拼车出行的市场渗透率高度相关,不合理的奖励方案容易导致成本增加,甚至项目破产。为进一步激发拼车需求,合理利用交通资源,文中提出一种基于路段的拼车奖励方案优化模型,以拼车为支点,以奖励为杠杆,实现社会出行总成本的降低。其中,上层模型旨在寻找最优拼车奖励方案以最小化社会出行总成本,下层模型为相应奖励方案下的拼车出行车辆和单人驾驶车辆用户均衡流量分配模型。采用嵌套Frank-Wolfe算法的遗传算法求解该模型,并以Sioux Falls路网和Nguyen Dupuis路网为算例对模型的可行性及有效性进行了验证。结果表明:不符合市场渗透率的预算投入会导致社会总成本大幅上涨;在最优拼车奖励方案下,社会出行总成本降低约24.53%,50%的拥堵路段的拥堵得到缓解,出行公平性问题得到缓和。文中提出的模型可为道路管理者设置科学、合理的拼车奖励方案提供理论基础。

公立医院预算绩效管理体系建设及相关问题探讨

为更好发挥预算对公立医院建设的支撑、调控、服务作用,公立医院加强预算绩效管理,将其作为保障财力有效转化为发展力的重要抓手。本文基于史密斯政策执行过程模型分析预算绩效管理,对政策制定、执行、监督以及评价全部流程和环节进行分析,剖析其中存在的问题及原因,提出公立医院预算绩效管理体系优化方向,健全政策体系,完善政策目标;优化执行机构,提升执行能力;提升目标群体,强化参与意识;改善执行环境,提供高效保障;强化外部约束,加大监督力度。

基于区域水平衡理论和SWAT模型的沁河流域水收支平衡演变分析

基于区域水平衡理论和SWAT模型,提出了分布式水收支平衡模型的构建思路及水收支平衡计算方法,对人类活动和未来气候变化情景下的沁河流域水收支平衡状况进行模拟,并通过皮尔逊相关系数和Mann-Kendall检验方法分析了水收支平衡的关键影响要素及其演变规律。结果表明:2010—2016年沁河流域蓄水总量呈下降趋势,降水量及出口径流量为沁河流域水收支平衡相对关键的影响要素;未来多气候情景下蓄水总量呈上升趋势,多年平均降水量及出口径流量两个关键影响要素的总体变化情况与辐射强迫水平呈正相关关系;典型气候情景SSP2-4.5下降水量及出口径流量在2037—2041年、2061—2063年可能存在突变。

基于部分预算法下加气灌溉技术经济效益分析

加气灌溉是目前最为高效的节水灌溉技术之一,是在地下滴灌的基础上,利用空气泵或气泡发射器提高土壤含氧量的一种灌溉方法。为了明确加气灌溉技术在大田作物种植中的主要应用效果与经济效益,为加气灌溉技术在农业生产中的推广及应用提供理论依据,采用部分预算法对田间加气灌溉后的经济效益进行综合评价。研究结果表明:与常规滴灌技术相比,加气灌溉技术与常规种植技术相比,总收益分别为25400.05元/hm^(2)和20162.14元/hm^(2);从农业净收益来看,加气灌溉技术可以增加326.03元/hm^(2),部分投资收益率超过700%;加气灌溉技术可以显著减少农业灌溉用水量,提高作物产量,提升农业经济收益,具有良好的应用推广价值。

Nitrogen and phosphorus budgets of the Changjiang River estuary

Eutrophication has emerged as a key environmental problem in Chinese coastal waters, especially in the Changjiang (Yangtze) River estuary. In this area, large nutrient inputs result in frequent harmful algal blooms and serious hypoxia in bottom waters. Four cruises were made in the estuary in 2006 to assess the concentration and distribution of dissolved inorganic nitrogen (DIN) and phosphorus (DIP). The concentration of DIN decreased gradually in a linear relationship with salinity from the river mouth to outer waters, while DIP was relatively more dispersed. A modified box budget method was used to estimate nutrient fluxes in the estuary and its adjacent waters. Water and nutrient budgets as well as primary production and denitrification rates were estimated from the box budget model. Estimated water residence time in the estuary was about 11 d. The turbid mixing zone released 33% of DIN and 49% of DIP, while in the adjacent outer sea 17.9 mmol DIN/m2·d and 0.36 mmol DIP/m2·d were fixed. Dissolved inorganic phosphorus was imported from the deep open sea waters, supporting primary production and population growth in this zone. Net ecosystem production (NEP) was calculated at 38.2 mmol/m2·d in the outer estuary and the estimated rate (N-fixation minus denitrification) was negative (1.92 mmol/m2·d), implying that a large amount of input nitrogen was taken up by algae and recycled through denitrification in bottom water and sediment.

基于多元线性回归的年度销量预测方法

基于业财融合的卷烟业务预算管理有利于平衡生产与需求、协同工商业,而对卷烟年度销售总量预测,建立切实合理的年度销售计划是实现高效有用的预算管理的前提。文章根据2010—2021年凉山烟草商业公司历年销售的相关数据,基于卷烟销售“人口确定销量,经济确定结构”的原则,选取常住人口数、城镇人口、乡村人口、性别结构、游客数指标、生产者物价指数、城镇化、城镇人均可支配收入8个指标作为解释变量,利用STATA软件建立多元线性回归模型。结果表明,该模型能够较好地预测出凉山烟草商业公司年度销售总量值的变化。

甘南高寒草甸碳收支时空格局及动态模拟

草甸生态系统具有强大的碳汇功能,在全球碳循环过程中发挥着重要作用。区域尺度草甸生态系统碳通量的精准模拟,可以为揭示草地碳循环对全球变化的反馈机制提供理论依据。生态过程模型则是分析和预测区域碳平衡的重要途径。以甘南州高寒草甸生态系统为研究对象,利用参数优化后的Biome-BGC模型,模拟1979—2018年高寒草甸总初级生产力(Gross Primary Productivity,GPP)和净生态系统生产力(Net Ecosystem Productivity,NEP),以表征该区域碳收支的时空分布特征。以上述40年实测气象数据为基准,并结合第六次国际耦合模式比较计划(Coupled Model Intercomparison Project phase 6,CMIP6)中的3种共享社会经济路径(Shared Socio-economic Pathways,SSPs)情景,对甘南州2019—2100年高寒草甸碳收支进行情景模拟。结果表明:(1)参数优化后的Biome-BGC模型能较好的模拟甘南州高寒草甸GPP和NEP,且GPP模拟对比NEP的模拟效果更好;(2)甘南州高寒草甸在整个研究阶段表现为碳汇,过去40年GPP、NEP波动范围为600—1100 g C m^(-2) a^(-1)、150—300 g C m^(-2) a^(-1),GPP显著上升,NEP呈波动性上升趋势。未来暖湿化情景下,高寒草甸碳收支年际波动较大,NEP呈先上升再下降趋势,2060年前后出现极小值,年均增幅约为2.02 g C m^(-2) a^(-1),气温、降水和大气CO_(2)浓度升高共同影响该地碳收支格局;(3)季节尺度上表现为冬春季节为碳源、夏秋季节为碳汇,植被生长季固碳作用增强。年内GPP、NEP呈倒“U”型变化趋势,峰值均出现在7、8月,低温以及持续增温对碳汇具有抑制作用,生长季降水量与植被生产力呈正相关;(4)碳汇/碳源的空间分布随时间而变化,具有明显的地域差异性,总体上碳汇增长率由西南向东北递减。

基于全气象参数的南水北调中线冬季水气热交换模型

针对南水北调中线干渠水体表面热交换精细模拟技术欠缺和多气象因素相互作用机理不明等关键问题,考虑太阳高度角、日照时间、云层遮挡和反照率等因素对太阳辐射的影响,并综合分析水体吸收、反射和发射的净长波辐射、涵盖水体蒸散发失热、水面温差引起的热传导和降雪引起的失热,建立了基于全气象参数的大型明渠水气热交换数学模型。结合南水北调中线全线通水后5年的冬季水温、气温、相对湿度、气压、风速、太阳辐射等原型观测资料,重点分析和模拟了典型年北拒马河、漕河渡槽和滹沱河倒虹吸等渠池的净热通量量值及其组分占比。结果表明,模型能够精细模拟不同渠池水体逐小时吸收的太阳辐射、释放的长波辐射、蒸发失热和水气热传导。模拟结果和观测资料均显示中线干渠冬季以失热为主,其中太阳辐射对净热通量的贡献最大,其次分别为长波辐射、蒸散发失热、温差引起的热传导,占比分别为43.1%、30.9%、17.2%和8.8%。本文量化了中线干渠冬季热通量组成,为进一步研究中线水温冰情精细模拟和输水能力提升提供了基础。

长江向家坝建库对库区水体温热收支定量研究

向家坝等水库的修建和调度一方面为人类发展提供了宝贵的水资源和清洁能源,另一方面也改变了天然河道的温热收支过程。本研究利用水量平衡方程和能量平衡方程构建箱式模型,并辅以库区一维水动力模型来减小无坝条件下的库区河道的纵向水位分布计算误差,通过情景计算揭示了有无坝体各部分热量收支的占比及差。结果表明:水库的运行使得水体储热过程在时间尺度上更加稳定,建库后水体总热能为天然情况下的7~35倍,同时也使得库区水体具有一定的“滞温”效应,最高滞后42天;建库后库区水体接收的太阳辐射热能相较天然状态最高提升了388%,最低提升283%,蒸发耗能方面的热量损耗最高提升了391%,最低提升284%,两者热能提升的最高值和最低值均发生在2月和8月,总体效应为热能净收入增加。研究结果可为梯级水库的规划、建设和调度对温热收支的影响提供重要依据,在温热影响层面为保护库区上下游水体生态系统提供部分科学支持。

效能提升视角下政府科研项目资助与管理机制分析:以“揭榜挂帅”“赛马制”和“首席制”为例

在当前财政收入增速放缓、社会经济发展对科技创新需求空前高涨的背景之下,如何有效选择科研项目的资助与管理机制,通过向管理要效率,提升政府科技投入效能成为政府项目资助与管理面临的重要问题。“揭榜挂帅”等新的科研项目管理机制自提出和进行实践探索以来,已有相关研究缺乏对其具体模式进行综合性比较分析,特别是缺乏对其使用条件和选择依据等方面的研究。为此,从政府科研项目的科学目标确定性与资源充分性出发构建政府科研项目资助与管理机制的二维分析模型(以下简称“二维模型”),并基于此以“揭榜挂帅”“赛马制”和“首席制”等3种典型的项目管理机制为例进行比较分析。根据二维模型,政府项目管理机制的重点,对于资源充足、资助目标明确具体的项目主要在于如何快速达成目标,对于资源充足、资助目标不够明确具体的项目在于过程管理,对于资源有限、资助目标明确具体的项目在于如何利用有限的资源最大限度完成资助目标,而对于资源有限、资助目标不够明确的项目则通常不考虑进行资助。综合比较来看,“揭榜挂帅”极其注重研究成果,属于出口竞争,适用于政府资源充足且资助目标明确具体的情境;“赛马制”将资源聚焦优势主体,偏向于出口竞争,适用于政府资源相对有限而资助目标明确具体的情境;“首席制”强调首席角色的战略眼光及个人能力,属于入口竞争,适用于政府资源充足而目标宏观的情境。最后,从理清政府资助目标与资源、基于实际需求有针对性地选择适宜模式并动态灵活调整管理机制,以及兼顾政府宏观指导与市场配置资源作用等方面,提出新形势下中国政府科研项目资助管理机制选择的政策建议。

煤炭贸易企业业财融合的预算管理模式探究

煤炭贸易企业在国内市场占比越来越大,对财务管理的要求也越来越高。然而,在激烈的市场竞争中,部分企业仍沿用传统的财务管理模式,难以满足现代企业的发展需求,亟须引入业财融合的预算管理模式。因此,文章以煤炭贸易企业业财融合预算管理模式的概念和背景为切入点,指出了该模式的三大优势,分析了现存的三个主要问题,并提出了五点推进煤炭贸易企业业财融合预算管理模式的应用策略,以为相关企业提供借鉴。

微纳卫星测控系统链路预算与仿真

为了解决微纳卫星通信设备的尺寸限制和功耗限制问题,提高测控链路传输性能和可靠性,建立了遥测预算模型和遥控预算模型,分析了传输链路的各个组成部分,并结合微纳卫星的特点对传输链路进行预算。通过对各个参数之间进行权衡,将链路裕度控制在合理范围之内,并通过仿真进行验证,为工程实践提供参考。

新时期汽车行业新产品研发费用财务管理优化思路研究

新时期汽车行业的市场竞争处于白热化状态,对汽车企业而言,新产品研发费用投入金额既关系到企业未来的发展战略,同时又对企业当期的盈利状态有重大影响。科学有效地管理研发费用对企业的发展至关重要,文章旨在通过运用数字化工具进行精细化管理,搭建投资模型,完善研发费用财务管理体系,做好研发费用的事前、事中和事后控制,将有限的资源效用最大化,助力企业在严峻的市场环境下取得竞争优势,并获得更长远的发展。

全面预算管理在电动汽车架构敏捷开发项目中的应用研究

为了应对日益加剧的竞争态势,很多车企开始开发电动汽车架构项目。电动汽车架构项目由于内外部环境变化,需要采用敏捷开发模式进行动态迭代,加剧了架构预算管理复杂度。文章结合某新能源车企的电动汽车架构敏捷开发项目,分析了电动汽车架构预算的使用特殊性和痛点,以及建立全面预算管理机制的必要性,并提出了加强预算过程控制、重视不可预计费用、建立“点-线-面”立体式预算管理机制以及明确输入输出物等解决措施,以期为同行业其他公司提高预算管理水平提供参考。

Sulfur Distribution and Transport Studies in East Asia Using Eulerian Model

A three-dimensional regional Eulenan model of sulfur deposition and transport is developed.Processes treated in the model include emission,transport,diffusion,gas-phase and aqueous-phase chemical process,dry deposition,ramout and washout of sulfur.A 'looking up table' method is provided to deal with the gas-phase chemical process including sulfur transfer Dry-depositon velocity considers the influence of underlying surface,wind,degree of stability by parameterization Model calculated values reasonably agrees with observation.Distribution of sulfur deposition and transport in East Asia are also analyzed in this paper Some amount of sulfur emission of different countries transport across boundaries,but the main origin of sulfur deposition in each country in East Asia is from itself.Furthermore.some transport paths on different layers and outlet or inlet zones are found.According to sulfur balance and budget we concluded that sulfur outlets are bigger than inlets across boundary and emissions are more than deposition in most places of East Asia

普及化时代地方高校生均拨款水平及其影响因素分析

在高等教育大众化与普及化过程中,地方高校生均拨款水平差距越来越大,生均拨款水平低于教育部标准12000元/生/年的问题严重。这可以从两方面进行解释:一是生均拨款水平制度的强制性变迁。二是生均拨款水平制度的诱致性变迁。高等教育体制适应计划经济向市场经济转轨,需要以基本公共服务均等化为理念,科学调整财政教育投入方式和高校的收支结构,不断缩小地区与校际间生均拨款水平的差距,恪守底线标准。