Theoretical calculations on Landé g-factors and quadratic Zeeman shift coefficients of nsnp ^(3)P_(0)^(o) clock states in Mg and Cd optical lattice clocks

The study of magnetic field effects on the clock transition of Mg and Cd optical lattice clocks is scarce.In this work,the hyperfine-induced Landég-factors and quadratic Zeeman shift coefficients of the nsnp ^(3)P_(0)^(o) clock states for ^(111,113)Cd and ^(25)Mg were calculated by using the multi-configuration Dirac–Hartree–Fock theory.To obtain accurate values of these parameters,the impact of electron correlations and furthermore the Breit interaction and quantum electrodynamical effects on the Zeeman and hyperfine interaction matrix elements,and energy separations were investigated in detail.We also estimated the contributions from perturbing states to the Landég-factors and quadratic Zeeman shift coefficients concerned so as to truncate the summation over the perturbing states without loss of accuracy.Our calculations provide important data for estimating the first-and second-order Zeeman shifts of the clock transition for the Cd and Mg optical lattice clocks.

Determination of Potential Runoff Coefficient Using GIS and Remote Sensing

Flash floods in arid environments are a major hazard feature to human and to the infrastructure. Shortage of accurate environmental data is main reason for inaccurate prediction of flash flooding characteristics. The curve number (CN) is a hydrologic number used to describe the storm water runoff potential for drainage area. This study introduces an approach to determine runoff coefficient in Jeddah, Saudi Arabia using remote sensing and GIS. Remote sensing and geographic information system techniques were used to obtain and prepare input data for hydrologic model. The land cover map was derived using maximum likelihood classification of a SPOT image. The soil properties (texture and permeability) were derived using the soil maps published my ministry of water and agriculture in Saudi Arabia. These soil parameters were used to classify the soil map into hydrological soil groups (HSG). Using the derived information within the hydrological modelling system, the runoff depth was predicted for an assumed severe storm scenario. The advantages of the proposed approach are simplicity, less input data, one software used for all steps, and its ability to be applied for any site. The results show that the runoff depth is directly proportional to runoff coefficient and the total volume of runoff is more than 136 million cubic meters for a rainfall of 103.6 mm.

Methodology for the Calculation of the Runoff Coefficient with the Arrangement Tirado

For this research work, an adequate methodology was sought for the calculation of the runoff coefficient with the Tirado arrangement. To achieve this, first, the variables that affect the runoff coefficient were identified, then the model was described with the Tirado arrangement, and as a third part for the calculation of the runoff coefficient, the Tirado model is proposed. From the theory for the calculation of the runoff coefficient, the equation of the weighted coefficients and the expression of Nadal were manipulated, resulting in the following relationship , considering this as the expression for the arrangement Tirado. The expression is tested with different intensities, the magnitudes correspond to 150, 200, 250 and 300 mm/hrs, resulting in runoff coefficient 0.82, 0.87, 0.89, 0.91 respectively. This means that, the higher the intensity, the runoff coefficient will be higher, logically the characteristics of the basin affect that this coefficient has variation in the space studied.

The Scale of Constructing Mountainous Cities in Yunnan Province based on “Benchmark” Farmlands

In 2011, Yunnan provincial committee and government proposed the strat- egy of constructing mountainous cities in order to protect farmlands and guarantee crop safety, which makes full use of hills and gentle-slopes and transforms land use pattern. However, social and economic development performs unevenly in Yun- nan, supplemented by varied geographical conditions, so that constructing mountain- ous cities should proceed as per local conditions. The research proposed the con- trol of constructing mountainous cities provided crop safety under the principle of farmland protection and measured the quantities of demanded construction lands ac- cording to science of population prediction and ekistics, based on which the control scales of constructing mountainous cities were determined by multiplying basic farm- land coefficient and the area of newly increased construction lands. The research is of significance for guiding the construction of mountainous cities and avoiding the occupation of construction lands on farmlands.

Relationship between Housing Price and Land Price Based on Grey Relational Analysis

In recent Years, China＇s real estate market has been rapid developed, and real estate has become a hot spot of consumption and investment. In some large and medium-sized cities there has been a rapid rise in housing prices. The rapid rise in housing prices has led to difficulties in the purchase of houses in some cities and towns, and this phenomenon has aroused the attention and con- cern of all walks of life. Housing is the basic human life needs. Housing problem is not only an economic problem, but also a social problem. The relationship between house price and land price and the effective control of housing prices have become the focus of government and scholars. Thus, grey relational analysis is used to ana- lyze the relationship between housing prices and land prices, and the grey relational coefficients are calculated.

ANALYSIS ON SPATIAL DIFFERENCE OF LAND USECHANGE BASED ON PHYSICAL AND CULTURALLANDSCAPE ATTRIBUTES──A Case Study at Mongolian AutonomousCounty of Qian Gorlos, Jilin Province

Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.

Estimation of Regional Evapotranspiration in Alpine Area and Its Response to Land Use Change:A Case Study in Three-River Headwaters Region of Qinghai-Tibet Plateau,China

Three-River Headwaters （TRH） region involved in this paper refers to the source region of the Changjiang （Yangtze） River, the Huanghe （Yellow） River and the Lancang River in China. Taking the TRH region of the Qing- hai-Tibet Plateau as a case, the annual evapotranspiration （ET） model developed by Zhang et al. （2001） was applied to evaluate mean annual ET in the alpine area, and the response of annual ET to land use change was analyzed. The plant-available water coefficient （w） of Zhang＇s model was revised by using vegetation-temperature condition index （VTCI） before annual ET was calculated in alpine area. The future land use scenario, an input of ET model, was spa- tially simulated by using the conversion of land use and its effects at small regional extent （CLUE-S） to study the re- sponse of ET to land use change. Results show that the relative errors between the simulated ET and that calculated by using water balance equation were 3.81% and the index of agreement was 0.69. This indicates that Zhang＇s ET model based on revised plant-available water coefficient is a scientific and practical tool to estimate the annual ET in the al- pine area. The annual ET in 2000 in the study area was 221.2 ram, 11.6 mm more than that in 1980. Average annual ET decreased from southeast to northwest, but the change of annual ET between 1980 and 2000 increased from southeast to northwest. As a vast and sparsely populated area, the population in the TRH region was extremely unbalanced and land use change was concentrated in very small regions. Thus, land use change had little effect on total annual ET in the study area but a great impact on its spatial distribution, and the effect of land use change on ET decreased with in- creasing precipitation. ET was most sensitive to the interconversion between forest and unused land, and was least sen- sitive to the interconversion between cropland and low-covered grassland.

Effectiveness of Land Use Structure Evolution to Industrial Structure Transformation

Scarcity of land resources and transformation of industrial structure is a pair of contradictory elements.We derive the characteristics of land use structure and industrial structure transformation in Xining City using Transformation Coefficient(TC):first,in the period 1999-2000,the land use structure coefficient(θ1) declined by 79.55%,but the overall evolution trend is gentle;second,the transformation coefficient of industrial structure(θ2) tended to decline ceaselessly on the whole,a decrease of 36.09%(overall,the transformation coefficient of industrial structure is slightly greater than the land use structure coefficient);third,the inter-annual variation of the two experienced ups and downs(in the period 1999-2007,the inter-annual variation was great and in the period 2008-2010,the inter-annual variation tended to be gentle).On the basis of autocorrelation and co-integration model,we draw the following conclusions through analysis:first,the land use structure in Xining City plays a role in promoting industrial structure transformation;second,there is a long-term equilibrium relationship between the two.Finally,relevant policy recommendations are put forward for the industrial development in Xining City.

Improvement of Evaluation Methods for Cultivated Land Quality

As the existing cultivated land quality evaluation index system is unable to accurately evaluate the quality of cultivated land after land remediation,a modified land use coefficient method was established in this study to calculate the land use coefficient of cultivated land after land remediation. An evaluation index system was first established for the land utilization level of cultivated land in the remediation areas.After that,the land utilization level index before and after the remediation was evaluated separately. The ratio of the two was used as the correction factor to correct the original land use coefficient. The corrected land use coefficient was used to evaluate the quality of cultivated land. The quality evaluation and verification of the land remediation areas in Yuzhou City were conducted. It was found that the land use coefficient corrected by the modified method was more consistent with that calculated by production method 5 years after the project acceptance. It suggests that the modified land use coefficient method reflects the impact of land remediation on the quality of cultivated land,and it is more suitable compared with the production method for the quality evaluation of cultivation land in remediation areas.

Allocation of New Construction Land Based on Land Competitiveness Evaluation

Connotation of land competitiveness is expatiated from both the narrow sense and broad sense. Evaluation index system of land competitiveness is established according to the 2008 China Statistical Yearbook and 2008 China Land Resources Statistical Yearbook. Efficiency Coefficient Method and Principal Component Analysis Method are used to evaluate the land competitiveness of 31 provincial units in China. Result shows that in the year 2007, land competitiveness gradually decreases from southeast to northwest. The land competitiveness and GDP per unit land have significant negative correlation. The rank of approved new construction land has low positive correlation with the rank of land competitiveness in China. This indicates that there is little correlation between the allocation of regional new construction land and the land use efficiency. Therefore, it is suggested that regional allocation of new construction land should be treated differently based on the evaluation result of land competitiveness.

Assessment of ecosystem services value in response to prevailing and future land use/cover changes in Lahore,Pakistan

Land use/cover changes(LUCCs)significantly affect ecosystem services(ESs)and their corresponding monetary value.ESs can be evaluated to analyze the ecological and environmental changes caused by LUCCs.This research aims to estimate variations in the ecosystem services value(ESV)due to LUCCs in Lahore of Pakistan,and to offer information and recommendations to policy-makers concerned with the economic improvement of metropolis areas.We first investigated the historical LUCCs from 1990 to 2019,and then simulated the future land use/cover in 2030 and 2050 based on the CA-Markov model under three scenarios,including business-as-usual(BAU),rapid economic growth(REG),and coordinated environmental sustainability(CES).Subsequently,we evaluated the ESV from 1990 to 2050 and evaluated the historical and potential future ESV changes induced by LUCCs during 1990–2019 and 2019–2050,respectively.The results showed that,land use/cover exhibited an increase in built-up land and decreases in vegetation,water body,and unused land both in the past and future.The net ESV decreased from 58.26 million USD in 1990 to 50.31 million USD in 2019.In 2050,the decrease in ESV is most rapid under the REG scenario(decrease ESV of 7.13 million USD and decrease percentage of 14.18%),followed by the BAU(decrease ESV of 5.61 million USD and decrease percentage of 11.15%)and CES(decrease ESV of 5.18 million USD and decrease percentage of 10.30%)scenarios.For each ecosystem service type,the ESV of waste treatment decreased by 18.37%from 1990 to 2019,followed by soil formation and conservation(17.52%),biodiversity and maintenance(13.23%),climate regulation(11.80%),food production(11.69%),hydrological regulation(11.11%),and aesthetic value(3.07%).These outcomes indicate that continuous land use/cover planning should focus on regenerating aquatic areas and vegetation restoration.

Comparison of precipitation and evapotranspiration of five different land-cover types in the high mountainous region

Many rivers originate in high mountainous regions. However, the effects of climate warming on the runoff and water balance in these regions remain unclear due to the lack of observational data from harsh environments, and the variable influences of climate change on alpine land-cover types with different water balances. Using observations and simulations from Coup Model, water-balance values collected at five alpine land-cover types(steppe, shrub meadow, moist meadow, swamp meadow, and moraine) in a small alpine watershed, the Qilian Mountains in Northwest China, from October 2008 to September 2014, were compared. Measured evapotranspiration, multilayer soil temperatures and water contents, and frozen-depth data were used to validate Coup Model outputs. The results show that elevation is the primary influence on precipitation, evapotranspiration, and runoff coefficients in alpine regions. Land-cover types at higher elevations receive more precipitation and have a larger runoff coefficient. Notably, climate warming not only increases evapotranspiration but also particularly increases the evapotranspiration/precipitation ratio due to an upward shift in the optimum elevation of plant species. These factors lead to decrease runoff coefficients in alpine basins.

Comparing Land Degradation and Regeneration Trends in China Drylands

The aim of this paper is to offer a statistically sound method to make a precise account of the speed of land degradation and regeneration processes.Most common analyses of land degradation focus instead on the extent of degraded areas,rather than on the intensity of degradation processes.The study was implemented for the Potential Extent of Desertification in China(PEDC),composed by arid,semi-arid,and dry sub-humid regions and refers to the period 2002 to 2012.The metrics were standard partial regression coefficients from stepwise regressions,fitted using Net Primary Productivity as the dependent variable,and year number and aridity as predictors.The results indicate that:①the extension of degrading lands(292896 km 2 or 9.12%of PEDC)overcomes the area that is recovering(194560 km 2 or 6.06%of PEDC);and②the intensity of degrading trends is lower than that of increasing trends in three land cover types(grassland,desert,and crops)and in two aridity levels(semi-arid and dry sub-humid).Such an outcome might pinpoint restoration policies by the Chinese government,and document a possible case of hysteresis.

大型飞机多支柱交联式起落架一体化载荷校准及建模研究

针对某大型飞机多支柱交联式起落架结构受力及传力特点,首次采用一体校准、独立建模的载荷试验方法,三支柱起落架侧挂正向一体安装、一体加载,解决了多支柱之间的载荷影响问题。根据交联式多支柱结构受力及传力特点,进行应变电桥及载荷工况设计,载荷工况既包括常规的单支柱加载,还包括满足多支柱影响的两支柱及三支柱组合加载工况。提出了多支柱广义响应系数概念,并通过广义响应系数对支柱之间的影响效果进行分析,显示支柱载荷向前单向传递,后支柱影响紧邻前支柱,前支柱不影响后支柱。据此提出了支柱独立建模、载荷逐次迭代、基于广义响应系数的支柱消扰载荷建模方法,获得了满足精度要求的载荷模型。

吹风比和肋板对叶片尾缘开缝气膜冷却特性的影响

为了阐明吹风比和肋板对燃气透平叶片尾缘开缝区域气膜冷却性能的影响,采用延迟-分离涡模拟方法求解了尾缘开缝模型的流量系数、非定常流场结构和气膜冷却效率,采用实验数据考核了延迟-分离涡模拟方法对流量系数和气膜冷却效率预测的有效性,获得了使尾缘开缝壁面气膜冷却效率最佳吹风比。结果表明:流量系数随吹风比增加而增大,但吹风比大于0.65后,流量系数几乎不受吹风比影响;在吹风比0.20~0.65范围内,尾缘开缝壁面气膜冷却效率随吹风比增加而增加;在吹风比0.80~1.25范围内,冷热气掺混剧烈,冷却效率略微下降;肋板结构增加了冷气通道的阻塞效应,并限制了开缝区域冷气旋涡的发展,导致展向涡提前扭曲、变形和分解;相对于无肋板结构,带肋尾缘开缝结构的流量系数下降了约5%,气膜冷却性能提升了约10.8%。开缝下游的旋涡脱落和冷热气流间的掺混是影响开缝壁面冷却效率的主要原因,综合考虑冷气消耗和气膜冷却效率,无肋板时最佳吹风比为0.65,带肋板时最佳吹风比为0.5。

塔里木河流域农业水土资源时空匹配关系研究

农业水土资源可持续利用是推进塔里木河流域生态文明建设、协调兵团向南发展战略部署以及促进各产业融合发展的重要基础。本研究基于2005-2020年塔里木河流域5个地区的农业水土资源匹配现状,运用基尼系数法、农业水土资源匹配系数以及农业水土资源当量系数,结合ArcGIS软件对塔里木河流域水土资源时空匹配状况进行分析。结果表明:从地理分布上来看,塔里木河流域耕地资源主要集中在喀什地区、阿克苏地区,耕地资源分布和水资源有密切关系。在研究时间跨度内,水土资源基尼系数在0.05~0.12之间,整体表现为波动变化,但是变化幅度不大,处于绝对均衡水平。农业水土资源匹配系数在研究期内呈现出先下降后升高再下降的特征,5个地区的农业水土资源匹配系数逐渐趋于一致,并稳定在1~2之间。结合当量系数分析,虽然塔里木河流域5个地区的农业水土资源均衡程度较好,但是5个地区仍处于极度缺水状态,且地区差异大。研究表明,塔里木河流域水土资源分布一致,整体处于缺水状态,随着节水力度的增大农用水占比呈下降趋势。

基于土地利用变化的江苏省碳排放时空差异与碳平衡分区

以江苏省13个设区市为例,基于碳排放(CE)和碳吸收估算方法,分析2005—2020年江苏省市域碳收支和碳补偿率的时空演变特征,随后引入环境基尼系数(EGC)从经济和生态两个角度分析空间碳平衡特征。结果表明:2005—2020年,江苏省土地利用碳排放从14210.005×10^(4)t增至23015.325×10^(4)t,碳吸收3039.383×10^(4)t波动上升至3628.703×10^(4)t,总体表现为碳源;13个设区市的碳补偿率整体呈现下降趋势,碳排放量与经济发展水平处于比较协调状态,与其人口聚集协调性较高;根据碳平衡分析,将13个设区市划分为碳汇功能区、低碳保持区、经济发展区、碳强度控制区、高碳优化区5类,并建议前两个分区充分发挥生态优势,着重推进生态产品价值变现;其余分区优先推动产业低碳转型,能源绿色化发展。

北部湾城市群耕地集约利用空间异质性及其影响因素分析

为探究城市群耕地集约利用的空间异质性及影响因素与作用机理,本研究在综合评价框架下,从自然和人文两方面构建评测体系,运用主成分分析、Dagum基尼系数和地理加权回归模型,对2021年北部湾城市群进行实证分析。结果表明:耕地集约利用指数为0.334,基尼系数为0.183,以低度集约为主且存在明显的空间非均衡性,超变密度(50.33%)和省域内差异(45.60%)是空间非均衡的主要来源。气温(0.491)、农业播种面积占比(0.273)、高程(0.165)和城镇用地集约度(0.146)的地理加权回归系数相对较大且为正,降水(-0.440)、城镇化率(-0.207)和建设投入强度(-0.170)的回归系数相对较小且为负,各因素存在空间非平稳性。研究表明,北部湾城市群耕地集约利用空间异质性表现为格局的空间非均衡性和因素的空间非平稳性,多因素之间体现了耕地利用自然因素是基础本底、农用土地集约经营正向促进、非农用土地集约利用负向抑制的作用机理,提高城镇用地集约度、统筹农业播种规模、量化耕地报酬是提升耕地集约利用的关键抓手。

潍坊市畜禽粪污土地承载力时空分布特征分析

为了科学评估潍坊市2012—2021年畜禽粪污土地承载力时空分布状况,准确评价畜禽养殖潜在环境风险状况,研究采用产排污系数法对潍坊市各县(市、区)2012—2021年畜禽粪污产生量、养分供给量、植物粪肥养分需求量及土地承载力指数等畜禽粪污土地承载力时空分布特征指标进行了分析。结果表明:潍坊市畜禽粪污土地承载力状况存在明显的时空分异特征。从时间上看,2012—2021年潍坊市各县(市、区)畜禽粪污产生量、养分供给量及植物粪肥养分需求量具有高度相似性,均呈现缓慢减少→稳定发展趋势。以氮、磷为基准的土地承载力指数(IN、IP)均呈现相对稳定趋势,其中IN均小于0.7,属于Ⅰ级,土地承载力有较大发展空间。除2017年外,其他年份IP均在0.7~1.0之间,属于Ⅱ级,土地承载力尚有发展空间。从空间上看,潍坊市各县(市、区)畜禽粪污产生量、养分供给量及植物粪肥养分需求量具有高度相似性,均呈现四周多中间少、东南和西北较多的分布特征。IN、IP存在一定差异,除临朐县外,其他县(市、区)IN平均值小于0.7,属于Ⅰ级,土地承载力有较大发展空间。临朐县IP平均值为1.59,属于Ⅳ级,存在明显超载情况;昌乐县、诸城市、高密市、昌邑市、安丘市、青州市IP平均值大于0.7,属于Ⅱ级,土地承载力尚有发展空间;其他县(市、区)IP平均值小于0.7,属于Ⅰ级,土地承载力有较大发展空间。说明潍坊市畜牧业有较大发展空间,应进一步优化养殖布局,调整种植结构,推动绿色养殖发展。

基于GIS技术农用地整理潜力测算方法研究——以哈巴河县为例

本研究基于2018年的土地利用变更调查数据,针对哈巴河县113个行政村的农用地整理潜力进行了综合分析。通过GIS空间分析和层次分析法,从数量和质量2个维度对耕地潜力进行了测算。研究发现,哈巴河县农用地整理区面积为34482.41 hm^(2),其中现有耕地面积为30904.50 hm^(2)。经测算,农用地整理的数量潜力为可增加耕地2900.05 hm^(2),新增耕地系数为8.41%。结合当地农作物种植结构体系测算农用地整理可增加耕地产能为3479.28 t。显示哈巴河县农用地整理潜力较大,根据新增耕地系数及耕地质量将整理潜力划分为4个等级。研究结果指出,哈巴河县农田建设应配套完善水利、道路等基础设施,加强农田防护,并通过农业生物科技措施改良土壤,提高耕地质量,提升土地利用率和耕地的产出效能。研究为该地今后土地整治规划提供了基础和依据。