Development unit division and favorable area evaluation for joint mining coalbed methane

Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step method” of optimal combination of production layers is corrected, and then the CBM production layer potential index is introduced to evaluate favorable areas for commingled multi-coal seam production. Through analysis of the key parameters of coal reservoirs affecting the CBM productivity index, a development unit division method for areas with multi-coal seams is established, and a quantitative grading index system is proposed. On this basis, the evaluation process of CBM development favorable area is developed: the mature 3-D modeling technology is used to characterize the reservoir physical properties of multi-coal seams in full-scale;the production layer potential index of each grid is calculated, and the production layer potential index contour under single-layer or commingled multi-layer production are plotted;according to the distribution of the contour of production layer potential index, the quantitative index of CBM development unit is adopted to outline the grade I, II, III coal reservoir distribution areas, and thus to pick out the favorable development areas. The practical application in the Yuwang block of Laochang in Yunnan proved that the favorable area evaluation process proposed can effectively overcome the defects of selecting favorable development areas only relying on evaluation results of a major coal seam pay, and enhance the accuracy of the evaluation results, meeting the requirements of selecting favorable areas for multi-coal seam commingled CBM production.

Fatigue life evaluation of girth butt weld within welded cast steel joints based on the extrapolation notch stress method

The fatigue life evaluation of the girth butt weld within the welded cast steel joint was studied based on the extrapolation notch stress method.Firstly,the mesh sensitivity of the finite element model of the welded cast steel joint was analyzed to determine the optimal mesh size.Based on the stress field analysis of the finite element model of the welded cast steel joint at the weld toe and weld root,the sharp model of the extrapolation notch stress method was applied to derive the effective notch stress of the rounded model belonging to the effective notch stress method,in which the key problem is to calculate the extrapolation point C,and the extrapolation point C has an exponential function relationship with the geometric parameters of the welded cast steel joint.By setting different values of geometric parameters,the corresponding value of parameter C is calculated,and then the functional relationship between the extrapolation point C and the geometric parameters can be obtained by the multiple linear regression analysis.Meanwhile,the fatigue life evaluation of the girth butt weld within welded cast steel joints based on the effective notch stress was performed according to the guideline recommended by the IIW(International Institute of Welding).The results indicate that the extrapolation notch stress method can effectively simplify the process of calculating the effective notch stress and accurately evaluate the fatigue life of the girth butt weld within welded cast steel joints.

Systematic evaluation and trial sequential analysis of warming acupuncture combined with joint mobilization in the treatment of scapulohumeral periarthritis

Objective:To evaluate the clinical efficacy of warming acupuncture combined with joint mobilization for the treatment of scapulohumeral periarthritis.Methods:A search for published randomized controlled trials(RCT)investigating warming acupuncture combined with joint mobilization for the treatment of scapulohumeral periarthritis was performed using the Cochrane Library,PubMed,Embase,and Web of Science databases.According to requirements of the Cochrane systematic review,all evaluations of RCT investigating warming acupuncture with joint mobilization in the treatment of scapulohumeral periarthritis were performed via method quality assessment,data extraction,and data analysis.Revman 5.3 and Stata 12.0 statistical software were used for the meta-analysis,and the trial sequential analysis(TSA)software estimated the required information size for each outcome.Results:A total of 14 articles were retrieved for meta-analysis,which included 551 cases in the treatment group and 539 cases in the control group.Meta-analysis showed that:(1)warming acupuncture combined with joint mobilization improved total efficiency[OR=6.16,95%CI(3.79,10.00),Z=7.34;P<0.001),TSA results confirmed the results of the meta-analysis;(2)warming acupuncture combined with joint mobilization improved the cure rate[OR=2.84,95%CI(2.19,3.70),P<0.001],TSA results revealed that no further tests were needed to verify;(3)warming acupuncture combined with joint mobilization reduced the number of treatments required for healing[MD=-7.49,95%CI(-9.75,-5.23),P<0.001],TSA results confirmed the results of the meta-analysis;(4)in comparing visual analog scale scores before and after treatment,meta-analysis result showed that:SMD=-2.01,95%CI(-2.37,-1.65),P<0.001,the difference was statistically significant,TSA results confirmed the results of the meta-analysis.Conclusion:Warming acupuncture combined with joint mobilization had a significant effect on the treatment of scapulohumeral periarthritis.

A Weighted Combination Forecasting Model for Power Load Based on Forecasting Model Selection and Fuzzy Scale Joint Evaluation

To solve the medium and long term power load forecasting problem,the combination forecasting method is further expanded and a weighted combination forecasting model for power load is put forward.This model is divided into two stages which are forecasting model selection and weighted combination forecasting.Based on Markov chain conversion and cloud model,the forecasting model selection is implanted and several outstanding models are selected for the combination forecasting.For the weighted combination forecasting,a fuzzy scale joint evaluation method is proposed to determine the weight of selected forecasting model.The percentage error and mean absolute percentage error of weighted combination forecasting result of the power consumption in a certain area of China are 0.7439%and 0.3198%,respectively,while the maximum values of these two indexes of single forecasting models are 5.2278%and 1.9497%.It shows that the forecasting indexes of proposed model are improved significantly compared with the single forecasting models.

The Way of Constructing the Diversified and Joint Administration Model of School-Enterprise Cooperation and Education

With the rapid development of the world,the needs of society and enterprises for all kinds of talents are also increasing.Of course,the cultivation of application-oriented talents is the demand for the survival and development of students,as well as the training goals of major schools.Through schoolenterprise cooperation,the employment rate of students can be effectively improved.However,due to the limitations of many conditions,the current diversified school-enterprise cooperation model also faces some problems.This article provides some measures for the problems that exist on the way and how to construct them.

Safety evaluation of replacement reinforcement quality in abutment contact zones of ultra-high arch dam in first impoundment period based on prototype monitoring

Reinforcement quality evaluation at the abutment is an important research direction. Prototype monitoring and theoretical derivation were integrated to study the replacement reinforcement quality in abutment contact zones of the Xiaowan ultra-high arch dam. The principles of monitoring layout and design are introduced in detail. Prototype monitoring shows that the increment of the interfacial compressive stress is much larger in the impoundment stage than in the regulating stage. The water pressure and time-effect are two main factors affeeting the interfacial stress. The time-effect is the key factor in the initial impoundment stage, and the water pressure is the key factor after impoundment. The contact properties are significantly improved by grouting. This study shows that there are three typical stages in the joint opening hydrographs, namely the compression stage, opening stage, and stable stage. There is a nonlinear relationship between the joint opening and temperature, which can be well described by the S-function. In conclusion, the reinforcement effect is satisfying, and the abutment is safe.

含分布式电源和电动汽车的配电网可靠性评估

针对目前大规模分布式电源和电动汽车接入配电网后,给配电网可靠性带来一定影响的问题,提出了一种含有分布式电源和电动汽车的新型配电网的可靠性评估方法。首先,考虑到风光出力的不确定性和相关性,选择拟合性最优的Frank-Copula函数,建立了风光联合出力概率模型。其次,分析了电动汽车用户行为特征,提出了基于动态分时电价的电动汽车有序充放电控制策略。最后,基于改进IEEE-RBTS Bus6测试系统的主馈线F4,对系统的可靠性指标进行计算分析,结果表明所提的风光联合出力模型和有序充放电控制策略可以有效降低对配电网可靠性的影响。

安徽省“水-土-能”系统安全评价及联合风险概率测算

水、土、能是人类生存和发展的重要自然资源。基于稳定性(S)、协调性(H)、可持续性(F)构建安徽省“水-土-能”系统安全评价指标体系,利用“单指标量化-多指标综合-多准则集成”(Single index quantification-multi-index comprehensive-multi-criteria integration,SMI-P)法测算各子系统指数及其系统安全水平,引入Copula函数分别探究S-H、S-F、H-F和S-H-F等不同组合的联合概率分布,测算其联合风险概率。结果显示:2012—2021年,安徽省“水-土-能”(“Water-Land-Energy”,WLE)系统安全水平波动上升,均值为0.5685,其中稳定性对系统安全水平影响最大;S-H、S-F、H-F分别呈弱正相关、强正相关、较强负相关关系,S-F联合风险概率最大,为0.2807;S-H-F系统联合风险概率为0.0712。当S、H、F其中一个固定时,另外两个的值越大,相应的联合风险概率越大。探究“水-土-能”系统安全水平及风险发生频率,有利于保障区域可持续发展,提高风险分析精度,为决策部门提供有效信息。

基于联合验证数据评定转化体定量检测结果测量不确定度

随着转基因生物及产品定量标识制度的不断完善,大批转化体定量检测方法的建立迫在眉睫,为了在实验数据积累不足的情况下,在检测方法建立初期及时评定测量不确定度,本研究以耐除草剂大豆DBN9004定量检测方法为例,在检测实验室积累到足够检测数据之前,在8家实验室对5种转基因含量样品进行联合验证,分析试验数据的再现性标准偏差,形成“自上而下”的不确定度预评定方法。结果显示:经格拉布斯法和科克伦法检验8家实验室数据,实验室5的数据存在离群值和岐离值,故剔除,7家实验室5个含量样品的再现性相对标准差RSD_(jR)为6.025%~11.532%,均小于规定的35%,说明该方法具有良好的精密度。根据上述分析数据绘制回归曲线方程为s_(jR)=0.0783×c/≡_(j)-0.0104,计算的相对标准不确定度分量u_(r)=0.0783,u_(0)=0.012,进而将试样检测结果的平均值(c=)带入公式,计算定量结果的标准不确定度u=√u_(0)^(2)+(u_(r)×c/=)^(2)=√0.012^(2)+(0.0783×c=)^(2)。结果表明基于联合验证数据评定转化体定量检测结果测量不确定度,为转化体定量检测方法建立初期提供了科学有效的实验室自行评定方法,为转基因生物及产品的安全监管提供了技术保障。

Qatar steps up to Global Health security:a reflection on the joint external evaluation,2016

Since the commencement of the International Health Regulations in 2007,global public health security has been faced with numerous emerging and ongoing events.Moreover,the Joint External Evaluation is a voluntary tool developed in compliance with the Global Health Security Agenda that represents the high responsibility of international health community towards the increased incidence of emerging and re-emerging diseases.Against this background,between 29th May and 2nd June 2016,a team of World Health Organization consultants arrived to the State of Qatar to assess,in collaboration with national experts,the country’s capacity to prevent,detect,and rapidly respond to threats of public health aspect.They identified areas of strength,weakness,and recommendations for improving national health security of Qatar in anticipation of the 2022 FIFA World Cup event.Qatar has demonstrated a leading role in the region through its commitment to International Health Regulations(2005)and population health.Similarly,the Qatar was the first Arab state and seventh volunteering country globally to undergo the Joint External evaluation process.In this review,we highlighted Qatar’s achievements and shortcomings of International Health Regulations’core capacities to inform healthcare professionals and the scientific community about the country’s contribution toward global health security.

上海市域铁路新建项目工程验收办法及安全评估方案研究

[目的]上海市域铁路已有多个项目开工建设,但目前尚无明确的市域铁路新建项目工程验收办法及安全评估管理办法。为了对市域铁路新建项目工程验收、安全评估等管理办法的制定提供合理化建议,亟需开展市域铁路项目工程验收办法及安全评估方案的研究。[方法]从主要技术标准、建设及运营特点两方面,分析了市域铁路同地铁、国家铁路的差异。阐述了地铁、国家铁路建设项目工程验收及安全评估程序,讨论了二者在项目验收组织、验收程序及验收内容等方面的差异。在此基础上,针对上海市域铁路新建项目工程验收及安全评估的具体工作流程,提出了2个备选方案(方案一、方案二),并对2个方案进行了比选,提出适用于上海市域铁路新建项目验收及安全评估工作流程的建议方案。[结果及结论]上海市域铁路新建项目的工程验收及安全评估建议采用方案二,即上海市域铁路项目工程验收的程序及组织方式基本沿用地铁模式,并参照国家铁路项目的标准设置联调联试流程。

考虑前车制动意图的自动紧急制动策略及其测试评价方法

为提高车辆自动紧急制动(AEB)系统的避撞性能,提出了一种考虑前车制动意图的AEB策略及其测试评价方法。通过搭建“PreScan+Simulink+驾驶模拟器”联合仿真平台采集驾驶人制动数据,基于K-均值(K-Means)聚类方法对制动意图进行分类,采用滑动时间窗口提取了意图识别模型训练数据集;通过双层隐马尔可夫模型识别前车制动意图,主车根据不同制动意图计算临界安全距离阈值并制定避撞控制策略;建立PreScan+Simulink虚拟仿真测试环境,提出了基于层次分析法的AEB策略综合评价方法,通过与4种典型AEB控制模型进行对比,验证了所提出方法在不同制动程度场景下均可及时触发制动以避免碰撞,同时可减少过早制动造成的驾驶不适感。

基于DEMATEL方法的科学基金项目绩效关键影响因素识别及实证研究——以促进海峡两岸科技合作联合基金项目为例

基础研究是应用研究和重大创新之源,联合基金作为国家基金委联合地方政府支持基础研究的主渠道之一,对提升地区原始创新能力、促进人才队伍建设发挥重要作用。为了真实反映促进海峡两岸科技合作联合基金资助项目的学术水平,从创新成果、人才培养、合作交流、项目延伸和间接影响等5个维度构建结题项目绩效评价指标体系,运用DEMATEL法分析15个二级指标之间的关联影响,结合多层次模糊综合评价法构建模型,并以某大学承担的重点支持项目为案例对影响项目绩效的关键因素进行实证分析,确定这个项目绩效评价等级。实证结果表明:DEMATEL法可以识别影响项目绩效的关键指标;模糊综合评价模型既考虑了评价对象的模糊性,也兼顾了指标体系的层次性,综合评价结果更具科学性。

专业核心课程群课程思政联合建设模式研究——以飞行器设计与工程专业为例

针对飞行器设计与工程专业的6门专业核心课——飞行器系统概论、空气动力学、飞行力学、结构力学、飞行器制导与控制和飞行器系统总体设计,开展6门课的课程思政联合建设模式研究。根据各门专业课的专业知识特点,建设“有中心、有主线、深融合”的体系化多层级联合课程思政资源库;分析6门课的开设时间及相应的学生学情,建设“有重点、分阶段、合规律”的课程思政联合形成性考核评价机制;针对每一门课,建设师生共建课程思政资源库、师生共同研究探讨课程思政主题、师生共同进步的知行合一课程思政教学方法。该联合课程思政建设方法可推广至专业所有课程的课程思政体系化建设中。

美军联合全域指挥与控制的投资

阐述美军联合全域指挥与控制(JADC2)的概念内涵、当前工作内容以及未来发展方向。结合美国国防部2024财年预算请求及Govini公司研究报告,进一步介绍JADC2支出的核算方法,并系统解析美国在JADC2上的资金投入和市场情况、美军联合全域指挥与控制当前面临的挑战。当前,全球安全环境正在发生飞速变化,局部冲突时有发生,搜集、解析和传递信息以保持决策优势的能力将是主导战争胜负的关键。美国国防部提出JADC2战略,旨在构建一个在战场上可以将各部门互联互通的安全网络,以期实现所有战域之间的充分、实时的信息交换。目前美国通过技术研发、合作演习等方式在各个层面积极推动JADC2的建设,并已取得一定阶段性成果。

气-液两相流装置的控制和不确定度评定

气-液两相流具有复杂的流动状态从而导致其无法被准确地控制,针对一套气-液两相流装置,对装置的压力-流量控制进行了研究,并对气-液两相的联合控制进行了实验,结果表明压力对控制具有较大影响。在控制过程中需要保证压力的不变,而气-液两相的联合控制具有变化的一致性,可通过研究一致性实现气-液两相的准确控制。同时对该装置的气-液两相流分量分别进行不确定度评定,结果表明,装置气体流量的U_(r)(Q_(v,air))=3.8%(k=2);装置液体流量的扩展不确定度U_(r)(Q_(v,liq))=3.2%(k=2),可对气-液两相的流量进行准确显示。

再定位咬合板治疗颞下颌关节盘可复性前移位的临床疗效和形态学评价

目的:观察再定位咬合板对颞下颌关节盘可复性前移位的临床疗效和治疗后颞下颌关节的形态学改变。方法:选取21例颞下颌关节盘可复性前移位患者,共36侧关节盘发生移位,戴用再定位咬合板治疗(6.8±1.4)个月,评价治疗1周和治疗结束时的临床疗效,治疗前和治疗结束时拍摄MRI,治疗前、治疗1周和治疗结束时拍摄CBCT,用于评估颞下颌关节盘形态、位置和关节间隙的改变。结果:治疗1周和治疗结束时关节弹响(有效率分别为80.95%和90.48%)和疼痛(有效率均为88.89%)均改善。治疗后部分关节盘恢复正常形态(双凹型占66.67%),部分(72.22%)关节盘完全复位;盘-髁距离减小(1.87±2.05)mm、盘-髁角度减小(17.75±11.57)°(P<0.05)。治疗1周和治疗结束时关节前间隙较治疗前均减小,上、后间隙均增大(P<0.05);治疗结束时关节前间隙较治疗1周增大,后间隙减小(P<0.05),关节上间隙变化无统计学意义(P>0.05)。结论:再定位咬合板治疗颞下颌关节盘可复性前移位可有效缓解症状,改善关节盘形态和位置,进而协调颞下颌关节盘-髁位置关系。

基于作战行动特征的作战指挥行为评估方法

为对兵棋推演过程中联合作战指挥员的作战指挥行为进行客观定量评估,提出了一种基于作战行动特征的作战指挥行为评估方法。根据联合作战指挥员指挥作战形成的作战事件序列构建作战事件知识图谱,采用双层图注意力网络和ConvKB模型抽取作战行动特征,基于CatBoost算法对联合作战指挥员的作战指挥行为进行评估。实验结果表明,该方法能够对联合作战指挥员的作战指挥行为进行客观有效评估。

基于信息量-Scoops3D联合模型的地质灾害易发性评价

贵渝管道沿线地势险峻、构造活跃、雨量集中,崩滑流等地质灾害十分发育,科学开展管道沿线地质灾害的易发性评估工作对确保其安全运行至关重要。本研究在查明管道沿线自然地质环境及地质灾害分布的基础上,结合管道沿线地形地质特征、管道展布与斜坡体的相互空间位置关系划分了101段适合管道工程特点的评价单元,基于信息量数理统计模型与Scoops3D物理力学模型对管道沿线地质灾害的易发性进行了评价。评价结果表明管道沿线地质灾害的高易发区主要集中在遵义及桐梓县附近,其中7段处于极高易发区,26段处于高易发区,20段处于中易发区,30段处于低易发区,18段处于极低易发区。通过ROC曲线分别求得信息量、Scoops3D以及二者联合模型的AUC值分别为0.796、0.683和0.803,结果表明信息量-Scoops3D联合模型的评价准确性最高。

血友病病人膝关节功能评估工具的研究进展

综述血友病病人膝关节功能相关评估工具的内容、特点、应用现状及局限性,提示医务人员在使用工具时应依据不同疾病的发展阶段和治疗情况选择评估工具,也可同时使用多个量表达到全面评估的目的。此外,现有的评估工具均来自国外,尚未检索到我国本土化的血友病病人关节功能和生活质量的相关评估工具,建议研究者开发适合我国国情的、具有良好信效度的评估工具,不断完善我国血友病关节功能的评估。