Water inrush evaluation of coal seam floor by integrating the water inrush coefficient and the information of water abundance

The method of singular coefficient of water inrush to achieve safety mining has limitation and one sidedness. Aiming at the problem above, large amounts of data about water inrush were collected. Then the data, including the maximum water inrush, water inrush coefficient and water abundance in aquifers of working face, were processed by the statistical analysis. The analysis results indicate that both water inrush coefficient and water abundance in aquifers should be taken into consideration when evaluating the danger of water inrush from coal seam floor. The prediction model of safe-mining evaluation grade was built by using the support vector machine, and the result shows that this model has high classification accuracy. A feasible classification system of water-inrush safety evaluation can be got by using the data visualization method which makes the implicit support vector machine models explicit.

Commercial Demonstration Unit for Manufacture of Aromatics from Toluene and Methanol with Coproduction of Low-Carbon Olefins Will Be Set Up

On November 29,2013 the Shaanxi Coal Chemicals Technology Engineering Center,Ltd.(SCCTEC),the CNOOC Huizhou Refining and Chemical Company and the SINOPEC Luoyang Engineering Company,Ltd.signed an agreement on cooperation in development of

Opening the doors of the intensive care unit to cancer patients: A current perspective

The introduction of new treatments for cancer and advances in the intensive care of critically ill cancer patients has improved the prognosis and survival. In recent years, the classical intensive care unit(ICU) admission comorbidity criteria used for this group of patients have been discouraged since the risk factors for death that have been studied, mainly the number and severity of organic failures, allow us to understand the determinants of the prognosis inside the ICU. However, the availability of intensive care resources is dissimilar by country, and these differences are known to alter the indications for admission to critical care setting. Three to five days of ICU management is warranted before making a final decision(ICU trial) to consider keep down intensive management of critically ill cancer patients. Nowadays, taking into account only the diagnosis of cancer to consider ICU admission of patients who need full-supporting management is no longer justified.

A Remark on Pl Type Interpolation on Non-Uniformly Distributed Nodes on the Unit Circle

In this paper we study the problem of explicit representation and convergence of Pal type （0;1） interpolation and its converse, with some additional conditions, on the non-uniformly distributed nodes on the unit circle obtaIned by projecting the interlaced zeros of Pn （x） and Pn′ （x） on the unit circle. The motivation to this problem can be traced to the recent studies on the regularity of Birkhoff interpolation and Pal type interpolations on non-uniformly distributed zeros on the unit circle.

α-Input and α-Unit Resolution Methods for Generalized Horn Clause Set in L_(V(n×2))F(X)

α-Input resolution and α-unit resolution for generalized Horn clause set are discussed in linguistic truth-valued lattice-valued first-order logic (LV(n×2)F(X)), which can represent and handle uncertain linguistic values-based information. Firstly the concepts of α-input resolution and α-unit resolution are presented, and the equivalence of them is shown. Then α-input (α-unit) resolution is equivalently transformed from LV(n×2)F(X) into that of LnP(X), and their soundness and completeness are also established. Finally an algorithm for α-unit resolution is contrived in LnP(X).

Approximation Algorithms for the Connected Dominating Set Problem in Unit Disk Graphs

The connected dominating set （CDS） problem, which consists of finding a smallest connected dominating set for graphs is an NP-hard problem in the unit disk graphs （UDGs）. This paper focuses on the CDS problem in wireless networks. Investigation of some properties of independent set （IS） in UDGs shows that geometric features of nodes distribution like angle and area can be used to design efficient heuristics for the approximation algorithms. Several constant factor approximation algorithms are presented for the CDS problem in UDGs. Simulation results show that the proposed algorithms perform better than some known ones.

融合GPU的拟单层覆盖近似集计算方法

拟单层覆盖粗糙集是一种匹配集值信息系统且有高质量和高效率的粗糙集模型。拟单层覆盖近似集的计算过程中存在大量计算密集且逻辑简单的运算,为此,提出拟单层覆盖近似集的矩阵化表示方法,以利用图形处理器(GPU)强大的计算性能加速计算过程。为了实现这一目标,使用布尔矩阵表示拟单层覆盖近似空间中的元素,引入与集合运算对应的布尔矩阵算子,提出拟单层覆盖粗糙近似集(DE、DA、DE0与DA0)的矩阵表示,并设计矩阵化拟单层覆盖近似集算法(M_SMC)。同时,相应的定理证明了拟单层覆盖近似集的矩阵表示形式与原始定义的等价性。然而,M_SMC运行过程中出现了矩阵存储和计算步骤的内存消耗过多问题。为了将算法部署到显存有限的GPU上,优化矩阵存储和计算步骤,提出分批处理的矩阵化拟单层覆盖近似集算法(BM_SMC)。在10个数据集上的实验结果表明,融合GPU的BM_SMC算法与单纯使用中央处理器(CPU)的BM_SMC算法相比计算效率提高2.16~11.3倍,BM_SMC算法可以在有限的存储空间条件下充分利用GPU,能够有效地提高拟单层覆盖近似集的计算效率。

异形双曲面楼承板节点构造及施工方法

为解决异形双曲面钢筋桁架组合楼板施工的难题,对某工程异形双曲面楼承板施工过程中的几种技术措施进行分析和总结,形成较为完整的施工工艺。总结的单元化、以直代曲等技术可为滑雪场、商业楼等异形双曲面钢筋桁架组合楼板施工提供借鉴。

大型燃煤火力发电机组调峰优化控制技术

调峰优化控制可以使得电网的源荷供需处于平衡状态,对提高火力发电机组调峰的稳定性至关重要。为此,提出一种大型燃煤火力发电机组调峰优化控制技术。构建爬坡压力缓解的目标函数,通过对火电机组、失负荷、储能以及光伏发电进行约束,以缓解爬坡压力。构建火力发电机组调峰优化控制的目标函数,结合火力发电机组在运行功率、功率平衡、启停机时间等方面的约束,实现了大型燃煤火力发电机组的调峰优化控制。实验结果表明,文中技术能够缓解大型燃煤火力发电机组的爬坡压力,优化了响应速度。通过所提技术的调峰优化实现了火力发电稳定运行,顺利完成调峰任务。

经阴道CO_(2)激光联合盆底生物反馈电刺激治疗阴道松弛症的疗效分析

目的通过观察经阴道CO_(2)激光联合盆底生物反馈电刺激治疗阴道松弛症的疗效,并与传统的盆底功能康复治疗进行疗效比较,探讨该治疗方式是否能够有效改善患者的阴道松弛程度,且能进一步改善阴道松弛症患者的生活质量。方法选择2022年11月1日至2023年6月30日就诊于我院盆底康复门诊的阴道松弛症患者60例,随机分为试验组和对照组,每组30例。对照组进行盆底功能康复治疗,包括1个疗程(10次)的盆底生物反馈电刺激治疗,治疗间歇期进行凯格尔训练。试验组每月进行1次经阴道CO_(2)激光治疗,连续2次为1个疗程,治疗间歇期间进行1个疗程(10次)的盆底生物反馈电刺激治疗。分别于治疗前、治疗后1个月进行女性性功能指数量表、女性性不适量表及肌力测定,对两组患者进行疗效评定。结果试验组患者治疗后的快速收缩阶段肌力、紧张收缩阶段肌力、耐力收缩阶段肌力均高于对照组,差异具有统计学意义(P<0.05)。试验组患者治疗后的性欲望、主观性唤起能力、性生活满意度、性交痛评分以及FSFI总分均优于对照组,差异具有统计学意义(P<0.05);但治疗前后两组患者的性活动时阴道湿润性、性高潮评分比较无明显统计学意义(P>0.05)。试验组患者治疗后的FSDS-R评分相较于对照组明显改善,差异具有统计学意义(P<0.05)。结论阴道松弛症患者采用经阴道CO_(2)激光与盆底生物反馈电刺激联合的治疗方法,能显著改善患者盆底肌功能,促进盆底正常肌力的恢复,并且能有效地提升患者在性行为中的感受及满意程度,疗效确切,安全性高,在阴道松弛症的临床治疗中具有应用价值和推广前景。

抽水蓄能机组过速保护值整定原则的探讨

本文对水电机组过速保护设置的目的、意义及其整定原则进行了初步探讨。对常规混流式水电机组和抽水蓄能机组分别发生飞逸后的机组转速变化曲线的相关特性进行分析比较,分析研究了抽水蓄能机组稳态飞逸转速和甩负荷后机组最高瞬态转速的相关情况,提出了抽水蓄能机组机械过速保护值和电气保护值的整定原则和方法。同时,结合实际工程案例,应用该整定方法对某抽水蓄能电站机组过速保护的整定值进行了计算分析,验证了该整定原则的工程实用性。

夏热冬冷地区地板辐射和风机盘管供暖的对比分析

为分析地板辐射供暖和风机盘管供暖在夏热冬冷地区的具体运行效果,对两种模式下的室内热舒适、供热能力和能耗进行了实验和OpenStudio模拟分析。实验和模拟结果表明:风机盘管系统在运行初期体现优势,但后期地板辐射供暖具有更好的室内舒适性,垂直峰谷差仅为0.03℃,预测平均值模型PMV为-0.28,预测不满意百分比指标(PPD)为6.83%;地板辐射供热能力大于风机盘管供热,且耗电量更低。

基于模糊粗糙集的大型汽轮机组设备故障识别方法

针对大型汽轮机组设备故障种类多,提出基于模糊粗糙集的大型汽轮机组设备故障识别方法。首先,模糊化处理大型汽轮机组设备故障信息,将复杂的故障信息转化为简单的模糊编码后,使用故障类型-征兆特征决策表生成方法构建特征决策表,表中各行代表故障类型,各列代表故障征兆特征;将决策表数据输入基于改进可拓神经网络聚类的故障分类模型中,决策表的历史数据作为训练数据,当下机组设备运行状态数据作为测试数据,通过判断当下设备运行状态是否与某故障类型-征兆特征决策表的数据匹配,完成设备故障识别。实验中,此方法可有效识别16种汽轮机组设备故障。

THE DESIGN AND ANALYSIS OF ALGORITHM OF MINIMUM COST SPANNING TREE

This paper provides a method of producing a minimum cost spanning tree (MCST) using set operations. It studies the data structure for implementation of set operations and the algorithm to be applied to this structure and proves the correctness and the complexity of the algorithm. This algorithm uses the FDG (formula to divide elements into groups) to sort (the FDG sorts a sequence of n elements in expected tir O(n)) and uses the method of path compression to find and to unite. Therefore. n produces an MCST of an undirected network having n vertices and e edges in expected time O(eG(n)).

Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

基于XLNet-BiGRU-Attention的行业分类方法

企业所属行业对于国民经济统计、市场监督管理等领域具有重要作用。在现如今庞大的行业规模下,人工进行企业行业分类不但效率低下,而且可靠性不高。在行业划分规范中,企业所属行业由企业的经营范围描述而得。针对传统词向量加机器学习的方法难以有效融合企业经营范围上下文语义信息等问题,提出了一种XLNet-BiGRU-Attention的行业分类方法。该方法首先通过XLNet网络从企业经营范围文本中获取具有上下文特征信息的语义表征向量,其次构建基于双向门限循环神经网络和注意力机制的候选集生成网络来进一步提取企业经营范围上下文相关特征,再次通过构建键值对嵌入网络来进一步挖掘企业其他标签对于行业分类的提升效果,最后将融合后的特征向量输入到分类器完成企业行业分类。相较于其他基线分类方法,该方法能够取得更好的行业分类效果。消融实验结果表明:该方法所构建的候选集生成网络和键值对嵌入网络能够提升行业分类的性能。

车底数最小化的动车组交路计划优化

基于现场生产需求,研究动车组交路计划优化问题。首先,界定动车组交路定义,分别以交路数最少、列车接续时间最短和车底数最少作为优化方向,分析3种目标下交路计划优化的不同效果,以及动车组交路计划的限制条件;然后,以所有动车组交路所需车底数最少为主要目标、以交路总时间最短为次要目标,考虑列车接续和动车组检修等约束条件,构建车底数最小化的动车组交路计划优化模型;最后,对整数非线性规划模型进行线性化处理,并依托上海局实际列车数据,对模型开展案例研究。结果表明:该模型可灵活转换优化目标,具有较好的灵活性和通用性;相比人工交路计划,该模型得到的优化计划减少车底数1列,缩短交路总时间420min;通过模型参数的灵敏度分析验证不同优化目标间的分歧性,并得出3条交路计划优化建议分别是,在保障动车组设备安全的前提下延长检修周期、提高车站作业效率并缩短动车组在站停留时间和压缩检修作业时间。

基于一种新的三模集的低通FIR数字滤波器设计

本文对低通有限脉冲响应(FIR)数字滤波器的设计进行了研究;在对常用三模集和传统的具有脉冲响应系数的FIR数字滤波器分析的基础上,提出将一种新的三模集应用于低通FIR数字滤波器设计的新方法。该FIR滤波器由多个乘法-累加器单元构成,实现正向转换器、并行算术通道和逆向转换器的功能。正向转换器将一个二进制数编码成一个关于模集的余数表示的数,每个算术通道对模集的每个模进行模乘和累加,逆向转换器将一个余数表示的数解码为其等效的二进制数,算术通道以完全并行的架构工作,从而实现轻量化的计算和简单的结构;最后的仿真实验结果不仅验证了本文提出的设计方法的有效性,而且相比于传统的单向转换设计,本文提出的设计方法有更小的滤波器系数偏差和更好的频率响应等波纹特性。

F_(2)^(n)中点集的线性不等式刻画

在分组密码的差分攻击中,为了利用计算机搜索最佳差分路径,人们将问题转换为其S-盒的差分分布表的最佳线性不等式逼近问题。确切地说,给定向量空间F_(2)^(n)的一个非空点集A,寻找数目尽可能少的一次多项式的集合,使得满足所有多项式的值均大于或等于0的点集恰好为给定的点集A。在文献中能看到的做法通常是利用计算机软件(例如SAGE数学软件)算出很多的多项式,再用线性规划的方法从中挑选出最小个数的多项式。研究一次多项式的产生方法,称F_(2)^(n)中的点集S是相容的,是指存在某个整系数一次多项式f(X),使得S={P∈F_(2)^(n)|f(P)<0}。主要有以下3个方面的结果:一是给定向量空间的维数n,对任意的1≤k≤2n,一定存在k元相容点集S;二是利用多项式加法的技巧,构造出一批k元相容点集;三是对于小参数k=1,2,3,4,给出k元点集S是相容的充分必要条件,同时也给出相应的k元相容点集的计数公式。

美国高校体育院系本科专业设置研究——以弗吉尼亚大学体育系为例

在一流专业建设的背景下,研究美国高校体育院系本科专业设置具有一定的理论与现实意义。研究以美国弗吉尼亚大学体育系为例,调查了其本科专业设置的基本情况,分析了专业设置的理念、特点与依据。研究发现,弗吉尼亚大学体育系设置了1个包括4个专业方向的体育学本科专业;该校专业设置秉承资源共享、追求质量和节约成本的理念,以适应社会发展与需求、学校的发展定位及办学能力、学科发展定位为专业设置依据,呈现出专业设置自主权较高、以科研为核心、关注健康相关领域、学生拥有较高选择专业方向自主权的专业设置特点。我国高校体育院系在专业设置方面可以适度扩大专业设置自主权,关注市场的变化与需求,加强与其他相关学科专业的联系,从而推动我国体育类专业人才培养水平的提升。