Importance of Weighting for Multi-Variable Habitat Suitability Index Model: A Case Study of Winter- Spring Cohort of Ommastrephes bartramii in the Northwestern Pacific Ocean

Weighting values for different habitat variables used in multi-factor habitat suitability index (HSI) modeling reflect the relative influences of different variables on distribution of fish species. Using the winter-spring cohort of neon flying squid (Ommastrephes bartramii) in the Northwestern Pacific Ocean as an example, we evaluated the impact of different weighting schemes on the HSI models based on sea surface temperature, gradient of sea surface temperature and sea surface height. We compared differences in predicted fishing effort and HSI values resulting from different weighting. The weighting for different habitat variables could greatly influence HSI modeling and should be carefully done based on their relative importance in influencing the resource spatial distribution. Weighting in a multi-factor HSI model should be further studied and optimization methods should be developed to improve forecasting squid spatial distributions.

Entropy weight coefficient model and its application in evaluation of groundwater vulnerability of the Sanjiang Plain

The research of groundwater vulnerability is the basic work to protect the groundwater. For utilizing groundwater resource continuably, groundwater vulnerability evaluation is necessary. Useful reference to protect, exploit and utilize on groundwater resource are provided rationally. According to the real condition of Sanjiang Plain, the indexes system is established based on the traditional DRASTIC model. The new system includes the following seven indexes： Depth of Water, Net Recharge, Aquifer Media, Soil Media, Conductivity of the Aquifer, Land Utilizing Ratio and Populace Density. The related analysis appears that the system is rather reasonable. Because traditional methods, such as analytic hierarchy process and fuzzy mathematics theory, can＇t be avoided human interference in selection of weights, they could lead to an imprecise result. In order to evaluate the groundwater vulnerability reasonably, entropy weight coefficient method is applied for the first time, which provides a new way to groundwater vulnerability evaluation. The method is a model whose weights are insured by the calculation process, so the artificial disturb can be avoided. It has been used to evaluate the groundwater vulnerability in Sanjiang Plain. The satisfied result is acquired. Comparably, the same result is acquired by the other method named projection pursuit evaluation based on real-coded accelerating genetic algorithm. It shows that entropy weight coefficient method is applicable on groundwater vulnerability evaluation. The evaluation result can provide reference on the decision-making departments.

Development of Empirical Models for the Estimation of CBR Value of Soil from Their Index Properties: A Case Study of the Ogbia-Nembe Road in Niger Delta Region of Nigeria

This study developed empirical-mathematical models to predict the California Bearing Ratio (CBR) using soil index properties in Ogbia-Nembe road in the Niger Delta region of Nigeria. The determination of CBR of soil is a laborious operation that requires a longer time and materials leading to increased cost and schedule;this can be reduced by adopting an empirical-mathematical model that can predict the CBR using other simpler soil index properties such as Plastic Limit (PL), the Liquid Limit (LL), the Plasticity Index (PI) and the Moisture Content (MC), which are less laborious and take lesser time to obtain. Thirteen models were developed to understand the relationship between these soil index properties: the independent variable and the California Bearing Ratio (CBR): the dependent variable;Six linear, Six quadratic and One multiple linear regression models were developed for this relationship. Analysis of variance (ANOVA) on the thirteen models showed that the Optimum Moisture Content (OMC) and the Maximum Dry Density (MDD) are better independent variables for the prediction of the CBR value of Ogbia-Nembe soil generating a quadratic model and a multiple linear regression model having a better coefficient of determination R2 = 0.96 and 0.94 respectively, mean square error (MSE) of 0.74 and 1.152 respectively with Root mean square errors of 0.861 and 1.073 accordingly. These models were used to predict the CBR of the soil. The CBR values predicted by the model were further compared with those of the actual experimental test and found to be relatively consistent with minimal variance. This establishes that CBR of any soil can be predicted from the Index Property of the soil and this is more economical and takes lesser time and can be universally adopted for soil investigation.

Investigation on the Long Term Operational Stability of Underground Energy Storage in Salt Rock

Underground energy storage is an important function of all energy supply systems,and especially concerning the seemingly eternal imbalance between production and demand.Salt rock underground energy storage,for one,is widely applied in both traditional and renewable energy fields;and this particular technique can be used to store natural gas,hydrogen,and compressed air.However,resource diversification and structural complexity make the supply system increasingly uncertain with the passing years,leading to great challenges for energy storage facilities in the present,and perhaps going into the future as well.Hence,it is necessary to research the operation stability of underground energy storage further.In this paper,a stability evaluation index system of Underground Gas Storage(UGS)is constructed with natural gas as the main medium,according to FLAC 3D cavity creep simulation software,along with fuzzy membership function to comprehensively determine the impact factor scoring model;the subjective weight is calculated based on the improved Analytic Hierarchy Process(AHP),the objective weight is calculated by the Entropy Weight Method(EWM),the combined constant weight is obtained by combining the variance maximization theory,and introducing the variable weight theory to obtain a more accurate combined variable weight.Finally,with this all being considered and accounted for,and with the four different conditions designed for UGS deployment case analysis and verification taken into consideration,the combined variable weight evaluation achieved excellent results;compared with the traditional constant weight method,in fact,the new evaluation results are more rigorous and objective.

Evaluation of global navigation satellite system spoofing efficacy

The spoofing capability of Global Navigation Satellite System(GNSS)represents an important confrontational capability for navigation security,and the success of planned missions may depend on the effective evaluation of spoofing capability.However,current evaluation systems face challenges arising from the irrationality of previous weighting methods,inapplicability of the conventional multi-attribute decision-making method and uncertainty existing in evaluation.To solve these difficulties,considering the validity of the obtained results,an evaluation method based on the game aggregated weight model and a joint approach involving the grey relational analysis and technique for order preference by similarity to an ideal solution(GRA-TOPSIS)are firstly proposed to determine the optimal scheme.Static and dynamic evaluation results under different schemes are then obtained via a fuzzy comprehensive assessment and an improved dynamic game method,to prioritize the deceptive efficacy of the equipment accurately and make pointed improvement for its core performance.The use of judging indicators,including Spearman rank correlation coefficient and so on,combined with obtained evaluation results,demonstrates the superiority of the proposed method and the optimal scheme by the horizontal comparison of different methods and vertical comparison of evaluation results.Finally,the results of field measurements and simulation tests show that the proposed method can better overcome the difficulties of existing methods and realize the effective evaluation.

Comprehensive Assessment of Urbanization Coordination:A Case Study of Jiangxi Province, China

In order to make assessment on urbanization coordination, we developed a comprehensive model by integrating entropy weight method(EWM), coupling degree model(CDM), coupling coordination degree model(CCDM), multi-index grading method(MIGM) and Remote Sensing & Geographic Information System(RS & GIS) technology. Then we applied this integrated model to a case study in Jiangxi Province, China. Our study finds that: 1) EWM, CDM and CCDM can evaluate the temporal dynamic of urbanization. Urbanization process of Jiangxi Province can be divided into three periods, the stable development period(1990–2001), the accelerated development period(2002–2009) and the rapid development period(2010–2015). Coordinated development of urbanization in Jiangxi Province can be divided into two phases, an increasingly coordinated phase(1990–2003) and an increasingly incongruous phase(2003–2015). The state transition was due to low development rate of population urbanization. 2) RS & GIS technology is an effective tool for detecting urban growth. Urban construction land area of Jiangxi Province increased from 615.8 km^2 in 1990 to 2896.8 km^2 in2015, and the per capita urban construction land area(PCUCLA) reached 122.9 m^2, with the maximum value of 343 m^2 in Gongqingcheng City. 3) MIGM and RS & GIS technology can analyze spatial difference of urbanization. There is a significant spatial difference in socioeconomic development at county scale, with the maximum value six times the minimum value for both PCUCLA and per capita GDP in 2015. Population urbanization lag and excessive land use are the main reasons for uncoordinated urbanization. There were 15 counties with a lag in demographic urbanization and 33 counties where PCUCLA exceeded the national standard in 2015, among which 20 exceeded the national standard of PCUCLA by 50%(≥165 m^2). Since there are significant spatio-temporal differences in urbanization, it is necessary to carry out a comprehensive assessment to facilitate differential urbanization strategy making.

Weighted estimation of single index models with right censored responses

In this paper, the unknown link function, the direction parameter, and the heteroscedastic variance in single index models are estimated by the random weight method under the random censorship, respectively. The central limit theory and the convergence rate of the law of the iterated logarithm for the estimator of the direction parameter are derived, respectively. The optimal convergence rates for the estimators of the link function and the heteroscedastic variance are obtained. Simulation results support the theoretical results of the paper.

Schedule Model for Project Portfolio Based on Design Structure Matrix

To improve the enterprise resource utilization and shorten the cycle of the whole project portfolio, a scheduling model based on Design Structure Matrix （DSM） is built. By setting the project activity weight index system and calculating the activity weight for the project portfolio, the constraint relationship between project portfolio information and resource utilization, as the two dimensions of the DSM, are fully reflected in the sched- ule model to determine the order of these activities of project portfolio. A project portfolio example is given to il- lustrate the applicability and effectiveness of the schedule model.

Three-Dimensional Model Retrieval Using Dynamic Multi-Descriptor Fusion

In this paper, we propose a dynamic multi-descriptor fusion （DMDF） approach to improving the retrieval accuracy of 3-dimensional （3D） model retrieval systems. First, an independent retrieval list is generated by using each individual descriptor. Second, we propose an automatic relevant/irrelevant models selection （ARMS） approach to selecting the relevant and irrelevant 3D models automatically without any user interaction. A weighted distance, in which the weight associated with each individual descriptor is learnt by using the selected relevant and irrelevant models, is used to measure the similarity between two 3D models. Furthermore, a descriptor-dependent adaptive query point movement （AQPM） approach is employed to update every feature vector. This set of new feature vectors is used to index 3D models in the next search process. Four 3D model databases are used to compare the retrieval accuracy of our proposed DMDF approach with several descriptors as well as some well-known information fusion methods. Experimental results have shown that our proposed DMDF approach provides a promising retrieval result and always yields the best retrieval accuracy.

不同地形梯度下秦巴山区乡村振兴潜力及发展路径

我国山地丘陵地区在空间上相对孤立,乡村发展受到阻碍。开展不同地形梯度下乡村振兴潜力及发展路径研究,旨在为山区因地制宜推进乡村振兴提供理论与科学依据。基于陕南秦巴山区地形差异开展典型村域调研,构建评价指标体系测度乡村振兴潜力,结合相关性与障碍度模型,辨识不同地形梯度下乡村振兴的障碍因素,提出差异化发展建议。结果表明:①各地形梯度下乡村振兴综合潜力由大到小依次为低地形梯度、中低地形梯度、高地形梯度、中高地形梯度,地形梯度与秦巴山区乡村振兴综合潜力及区位条件、基础设施潜力成显著负相关关系;②随着地形梯度的上升,秦巴山区乡村主体、产业发展、人居环境、区位条件、基础设施潜力整体上呈减小趋势,资源禀赋潜力先减小后增大;③不同地形梯度下秦巴山区乡村振兴各维度潜力大小及其障碍因子皆存在明显差异。为优化山区乡村发展模式、全面推进乡村振兴,建议低地形梯度村庄重点防止人口、耕地等农业生产要素流失,中低地形梯度村庄优化基层组织、提升引领能力,中高梯度村庄加强基础设施建设、改善人居环境,高地形梯度村庄充分保护并合理利用林地资源,发展特色产业。

钢坯定重动态智能调控技术探讨

近年来,随着棒材生产多线切分常态化,高速棒材生产技术及钢坯免加热直接轧制技术日益成熟,并得到广泛应用。在棒材生产过程中,许多企业实现了钢坯快速输送并直接轧制,生产效率大大提高。但是,轧钢生产线要求连铸工序对钢坯进行定重控制,采用跨单位电话通知方式进行人工调整,响应速度慢、稳定性差,难以满足快节奏的生产模式,导致轧后通尺量大,严重制约成材率指标的提高。因此,从连铸到轧钢工序系统考虑,通过建立数学模型,运用在线检测、信息计算技术,实现生产过程的动态调整,达到无人干预并自动控制的目的,为生产线实现高效智能制造提供切实可行的技术控制方法。

基于熵权—TOPSIS模型的A市农村乡镇快递网点建设能力评价体系构建

快递行业作为一种能够引导流通方式转型、挖掘消费潜力的现代化先导性产业,是现代服务业的重要组成部分。随着农村电商发展越来越多元化,农村寄递物流体系也随之愈加完善,但与各类条件都较好的城市地区快递体系相比仍存在末端网点服务能力较差、不稳定、利润低、基础设施薄弱等问题。为能够客观、科学的评价乡镇快递网点建设能力,提出一种基于熵权-TOPs Is模型的乡镇快递网点建设能力评价体系,实证分析的结果表明,构建的包含4个主因素共13个评价指标的乡镇快递网点建设能力的评价指标体系是可行和合理的,为快递企业科学地开展乡镇网点建设提供了理论指导。

基于TFAHP的电炉企业多维一体化财务模式评价模型

电炉企业的财务由于其参数指标众多,对相关模式评价过程不能运用单一阈值理论,评价过程一直是个难题。设计基于TFAHP的电炉企业多维一体化财务模式评价模型。通过微观模拟电炉企业财务工资过程,确定评价指标,由此构建模糊评价矩阵,依据模糊评价矩阵,构建二级评价矩阵,在单一准则下计算各评价指标的相对权重,采用三角模糊数层次分析法确定总权重,由此构建评价模型,获取评价结果,设定评价等级集合及区间值,给出具体评语等级。实验可知,所构建模型进行多维一体化财务模式评价在电炉企业应用效果较好,评价效率较高。

矿井通风系统综合评价指标体系与方法

对矿井通风系统进行科学合理的综合评价是矿井通风系统优化与调整的重要依据,目前仍未形成公认的综合评价指标体系与方法。针对矿井通风系统综合评价中存在指标体系的确定不够合理、权重维护困难等问题,采用理论分析、文献分析等方法,从矿井通风系统组成要素、性质、能力等3个角度,“通风动力、通风网络、通风设施”“安全可靠性、经济合理性”“保障能力、防灾能力、抗灾能力”等8个维度选取10项评价指标构建矿井通风系统综合评价指标体系。该评价指标体系可以从多角度、多维度全面反映被评价对象的综合情况,抓住主要因素,确保综合评价的全面性和可信度。同时,提出了以等距分级、等比赋权进行排序打分的权重确定方法,即专家排序指数赋权法,以快速确定与维护评价权重,使评价结果具有客观性,又易于操作。

考虑时空异质性的新能源汽车保有量增长态势研究

考虑到新能源汽车保有量增长的影响因素具有时间和空间双重属性,本文引入了时空地理加权回归模型在Arcgis平台上对居民消费水平、公共充电桩保有量、传统燃油车销量、每万人公共交通车辆、人口密度、城镇化率等6个指标因素进行了分析,并在此基础上建立了Bass扩散模型,对新能源汽车保有量的增长态势进行预测。研究结果表明:6个指标对保有量增长均存在明显的时空异质性,其中在初期阶段居民消费水平和公共充电桩数量对NEV保有量的影响程度最大;同时,通过外推预测模型预测东部地区新能源汽车到2030年会有5742万辆、中部地区将会达到2458万辆、西部地区将会达到1400万辆;至2050年东部地区将有新能源汽车2.12亿辆、中部则有1.46亿辆、西部有1.19亿辆。

陕西省生态环境对耕地利用生态效率的响应

[目的]揭示陕西省耕地利用生态效率、生态环境质量的时空分布特征,阐明生态环境质量对于耕地利用生态效率的响应方式,进而为陕西省农业高质量发展提供科学支撑。[方法]以陕西省为研究区域,基于遥感数据,计算了遥感生态指数以表征陕西省生态环境质量;利用SBM模型测度陕西省耕地利用生态效率;采用地理加权回归模型探究了生态环境对耕地利用生态效率的响应。[结果](1)2005年、2010年、2015年和2019年陕西省耕地利用生态效率总体上处于中等水平,有88%以上的地区属于低效率、较低效率和中等效率等级;(2)2005年、2010年、2015年和2019年陕西省生态环境质量在不断提高,黄土丘陵沟壑区和毛乌素沙地等地区生态环境质量有明显改善,空间格局总体上保持“南高北低”不变;(3)陕西省耕地利用生态效率和生态环境存在显著的正相关,相关关系空间分布具有不均衡性。[结论]陕西省生态环境与耕地利用生态效率的协同发展模式并不稳定,还需进一步探索与巩固。

基于结构方程模型的杉木林林分结构多样性评价

综合评价杉木林林分结构多样性,可为提高林分结构多样性和精准制定森林经营措施提供理论依据。以湖南省平江县福寿林场的杉木林为研究对象,利用4株邻近木构建林分空间结构单元,选取表征林分树种组成多样性的全混交度、Simpson多样性指数与Shannon-Wiener指数,表征林木大小分化多样性的大小变异系数、大小分化度均值指数与交角竞争指数和表征林木空间分布多样性的角尺度、林层指数与空间密度指数等9个指标,构建林分结构多样性评价结构方程模型,并确定各指标权重,对林分结构多样性进行综合评价。结果表明:(1)林分结构多样性评价结构方程模型的卡方自由度比值χ2/df为1.409,介于1—3之间,比较适配指数(CFI)、常规拟合指数(NFI)、增值适配指数(TLI)和拟合优度指数(GFI)的值分别为0.985、0.953、0.978和0.931,均大于0.9,近似误差均方根(RMSEA)为0.048,小于0.05,各指数的拟合效果良好,模型的适配度较好,满足研究的需要;(2)3个内生潜在变量林分树种组成多样性、林木大小分化多样性和林木空间分布多样性的权重分别为0.3518、0.3201和0.3281,对外生潜在变量林分结构多样性的影响大致一样,Shannon-Wiener指数是影响林分树种组成多样性的关键因素,交角竞争指数是影响林木大小分化多样性的关键因素,林层指数是影响林木空间分布多样性的最重要因素;(3)研究区3个龄组杉木林林分结构多样性的综合得分分别为0.3364、0.4396和0.4588,评价等级处于Ⅱ、Ⅲ等级,林分结构多样性较低,未达到理想的状态。评价结果较客观地表征了研究区杉木林林分结构多样性的现状,表明利用结构方程模型来评价林分结构多样性是科学、可行的,可为林分结构多样性评价提供一个全新的思路。

洞庭湖湿地潜流带地下水中氮磷迁移转化过程及驱动机制分析

为了揭示洞庭湖湿地潜流带地下水中氮磷的迁移转化过程,以洞庭湖湘江入湖口附近湿地为研究区,定期采集地表水和地下水水样进行水化学参数测试,采用熵权指数法进行水质评价,运用相关性分析、结构方程模型等方法研究理化参数对氮磷迁移转化的驱动机制。结果表明:58.8%的地下水水样为Ⅳ类或Ⅴ类水,TN、NH_(4)^(+)和TP是主要的超标因子,氮的迁移转化主要受矿化作用、反硝化作用和硝酸盐异化还原成铵等反应控制,磷的迁移富集与Fe/Mn氧化物或氢氧化物的还原性溶解密切相关;地下水中氮磷组分含量在丰水期和枯水期表现出明显差异,受潜流交换作用影响,除NH_(4)^(+)、溶解有机氮和TN外,地下水中NO_(2)^(-)、NO_(3)^(-)、TP和溶解态活性磷含量随着河岸距离增加而减小;温度、氧化还原电位、溶解氧、总溶解固体和电导率均会影响微生物活性,是地下水中氮磷迁移转化的关键驱动因子。

基于Geodetector和MGWR的贵州工业碳排放效率时空演化及影响因素分析

探究工业碳排放效率的时空演化及影响因素对区域产业绿色发展具有重要意义。基于2010—2020年贵州省9个市州的面板数据,利用super-SBM模型与Malmquist指数对工业碳排放效率进行静态和动态分析,并采用探索性时空数据分析方法揭示时空交互特征;基于此结合地理探测器和多尺度地理加权回归模型研究其影响因素。结果表明:①贵州工业碳排放效率整体呈上升趋势,年均增长率为8.45%。②技术进步是贵州工业碳排放效率提升的主要内动力。③工业碳排放效率空间自相关的时间路径长度呈现由东部市州向中、西部增大的趋势;贵州各市州的工业碳排放效率随时间演变呈现出较强的空间依赖关系。④对外开放程度、城市化水平、能源消耗强度、产业结构、重工业水平、生产力水平6个因素是影响工业碳排放效率的主导因子,且影响显著性出现不同程度的提高;对外开放程度、能源消耗强度与工业碳排放效率存在负相关,其余主导因子与工业碳排放效率呈正相关。

聚苯基甲基硅氧烷分子量-折射率模型研究

聚硅氧烷是应用广泛的一种特种有机硅材料,折射率是衡量聚硅氧烷性能的重要指标。应用基团贡献法建立了适用于聚苯基甲基硅氧烷体系的分子量-折射率模型,结合自由体积理论对模型进行了修正。修正后的模型能够根据分子量和温度有效地预测聚苯基甲基硅氧烷的折射率,相对误差在±0.2%范围内。根据修正后的模型阐述了分子量、温度对折射率的影响:折射率随着分子量的增大而升高,最终趋于一定值;折射率随着温度的升高明显下降。研究结果可为高折射率聚硅氧烷的设计与合成提供参考。