Applications of Soft Computing Methods in Backbreak Assessment in Surface Mines: A Comprehensive Review

Geo-engineering problems are known for their complexity and high uncertainty levels,requiring precise defini-tions,past experiences,logical reasoning,mathematical analysis,and practical insight to address them effectively.Soft Computing(SC)methods have gained popularity in engineering disciplines such as mining and civil engineering due to computer hardware and machine learning advancements.Unlike traditional hard computing approaches,SC models use soft values and fuzzy sets to navigate uncertain environments.This study focuses on the application of SC methods to predict backbreak,a common issue in blasting operations within mining and civil projects.Backbreak,which refers to the unintended fracturing of rock beyond the desired blast perimeter,can significantly impact project timelines and costs.This study aims to explore how SC methods can be effectively employed to anticipate and mitigate the undesirable consequences of blasting operations,specifically focusing on backbreak prediction.The research explores the complexities of backbreak prediction and highlights the potential benefits of utilizing SC methods to address this challenging issue in geo-engineering projects.

Synthesis and Characterization of Hollow Strontium Carbonate Pompons by Composite Soft Template Method

The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as template.The sampled particles were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption measurement,X-ray diffraction(XRD),Energy dispersive X-Ray spectroscopy(EDX),Fourier transform infrared spectroscopy(FTIR),Thermogravimetric analysis and differential scanning calorimetry(TGA-DSC),etc.It is shown that the assynthesized hollow strontium carbonate pompons with the size of about 2μm consist of flake-like particles under the optimal reaction conditions.The formation mechanism of hollow strontium carbonate pompons was preliminarily explored.

Numerical Study on an Applicable Underground Mining Method for Soft Extra-Thick Coal Seams in Thailand

The EGAT Mae Moh Mine is the largest open pit lignite mine in Thailand and it produces lignite about 16 million tons annually. In the near future, the pit limit of the mine will be reached and underground mine will then be developed through the open pit in the depth of 400 - 600 m from the surface. However, due to the challenges for underground mining such as poor geological conditions, extra thickness (20 - 30 m) of coal seams, and weak mechanical properties of coal seams and the surrounding rock, the success possibility of underground mining and an applicable underground mining method is being investigated at the present. The paper discusses the applicability of multi-slice bord-and-pillar method for the soft extra thick coal seams in the Mae Moh mine by means of numerical analyses using the 3D finite difference code “FLAC3D”.

Practical method and application study for predicting cyclic accumulative deformations of the saturated soft clay

The distribution of saturated soft clay is greatly wide in China. The current main measures adopted to deal with soft soil foundations may lead to environmental pollution, even some engineering accidents may happen on soft soil foundations. In order to solve engineering problems of saturated soft soil foundations well, researches of mechanical properties of them are necessary. One of the most important mechanical characteristics of saturated soft clay is its cyclic accumulative deformation under cyclic loadings. For saturated soft clay, the cyclic accumulative deformation is similar to the creep behavior under static loadings. Therefore, the cyclic accumulative deformation is equivalent to the creep, the number of loading cycles is seen as the time, and this study develops a practical method for predicting the cyclic accumulative deformation of saturated soft clay with the creep theory. The method is a pseudostatic elasto-plastic finite element method implemented by ABAQUS software. A fitted equation between cyclic accumulative strain and number of loading cycles and the empirical relationship of parameters of fitted equation were established with aseries of cyclic triaxial compression tests. Then with this empirical relationship of parameters, the method developed by this study was employed to predict the cyclic accumulative deformation under cyclic triaxial tension tests. Predicted results were in good agreement with test results, and the effectiveness of this method was thus validated for different stress states. The method was then applied in analyzing the cyclic accumulative deformation for soft soil foundation of a pile-supported wharf structure.

A modified soft docking method for proteins and peptides

A modified two-stage soft-docking procedure was developed for the theoretic researches on the recognition of protein-protein or protein-peptide complexes. Some systems have been used to test our program and the results are encouraging.

EIGHTY CASES of SOFT TISSUE INJURY TREATED WITH LOCAL CONTRALATERAL NEEDLING METHOD

Contralateral needling method is a common and effective one of acupuncture analgesicmethods.It is used to treat a local pain in the limbs and trunk with a short course of disease,pain and swelling will disappear or be relieved immediately for one or two treatments.Really,there isan effect of relieving pain as soon as the needle is inserted.When the local contralateral needlingmethod is used,the key to improving the effectiveness lies in determining the pain position and its correspondingpoint correctly,the more correct the pain position and its corresponding point are determined,the better the effectiveness will be.In this group,80 cases soft tissue injury were treatedwith local contralateral needling method,the cure rate was 82％,and the total effective rate was100％.

General Expressions of Triple Ⅰ Restriction Methods for Fuzzy Soft Reasoning

The aim of this paper is to discuss the Triple Ⅰ restriction reasoning methods for fuzzy soft sets. Triple Ⅰ restriction principles for fuzzy soft modus ponens(FSMP) and fuzzy soft modus tollens(FSMT) are proposed, and then, the general expressions of the Triple Ⅰ restriction reasoning method for FSMP and FSMT with respect to residual pairs are presented respectively. Finally, the optimal restriction solutions for Lukasiewicz and Godel implication operators are examined.

Development of mathematically motivated hybrid soft computing models for improved predictions of ultimate bearing capacity of shallow foundations

Ultimate bearing capacity(UBC)is a key subject in geotechnical/foundation engineering as it determines the limit of loads imposed on the foundation.The most reliable means of determining UBC is through experiment,but it is costly and time-consuming which has led to the development of various models based on the simplified assumptions.The outcomes of the models are usually validated with the experimental results,but a large gap usually exists between them.Therefore,a model that can give a close prediction of the experimental results is imperative.This study proposes a grasshopper optimization algorithm(GOA)and salp swarm algorithm(SSA)to optimize artificial neural networks(ANNs)using the existing UBC experimental database.The performances of the proposed models are evaluated using various statistical indices.The obtained results are compared with the existing models.The proposed models outperformed the existing models.The proposed hybrid GOA-ANN and SSA-ANN models are then transformed into mathematical forms that can be incorporated into geotechnical/foundation engineering design codes for accurate UBC measurements.

Engineering Geological Zoning of Soft-Soil Foundation Based on Combination Weighting and Extension Methods

Different criteria and factors are used in different methods of soft soil foundation settlement calculation and engineering geological zoning.The methods used are not universally suitable for complex geological environments.The post-construction settlement of soft soil foundations are especially large and difficult to calculate.In addition,there are many deficiencies in the current methods used for engineering geological zoning.Focusing on the need of establishing engineering geological zoning for areas with soft soil foundations in the Tianjin Marine Economic Area,combination weighting and extension methods were introduced.An evaluation model for the settlement of soft soil foundations was established using multiple factors and large amounts of data.This evaluation model is accurate and objective for delineating engineering geological zoning.These methods eliminate deficiencies by considering both objective and subjective factors,and help obtain an objective and accurate result.

岩土离心模型试验软接触式微型土压计研制及性能评价

微型土压计是岩土离心模型试验的重要测量技术之一。为解决刚性土压计测量中拱效应、尺寸效应、厚径比等经典误差问题及提升频响速率和精度,尝试开发了一种全新软接触式微型土压计ESP-II,介绍了其技术创新和设计方法。以两种国际代表性土压计为参考,设计开展一系列离心模型试验,对其感应精度、速率和适用性进行评价。主要结论:①逐级加载离心加速度5g~50g试验下,各深度ESP-II和两种参考传感器测试结果与理论值的平均误差分别为5.16%,6.70%,4.85%,三者沿深度拟合K_(0)优度系数R^(2)均≥0.9893。②脉冲荷载试验中ESP-II最大响应时间约7.8 ms,略优于两种参考传感器,具有良好的频响速率。③不同幅值正弦、地震等动荷载试验下,3种传感器测得土压力均呈一致增量趋势,K_(0)约由0.43~0.45增至0.51~0.56,与既有规律认识吻合。④离心机下降卸荷过程中,ESP-II测得时程表现良好连续性和光滑性,反映软接触式设计有利于保障土体与传感器良好接触和稳定响应。研究成果,初步证明了软接触式土压计适应于静、动力离心试验需求,具有重要价值与应用前景。

微种植体支抗加力方式对上颌前突患者关闭拔牙间隙后颌面部软、硬组织影响的研究

目的:探讨微种植体支抗加力方式对上颌前突患者关闭拔牙间隙后颌面部软、硬组织的影响。方法:选取2020年4月-2023年6月在上海交通大学医学院附属第九人民医院口腔外科、口腔颅颌面科收治的156例上颌前突患者作为研究对象。所有患者均需拔除上颌双侧第一前磨牙并使用微种植体支抗内收上前牙,采用随机数字表法将患者分入A组(予以短牵引钩和直接支抗法,n=52例)、B组(予以长牵引钩和直接支抗法,n=52例)和C组(予以短牵引钩和间接支抗法,n=52例)关闭拔牙间隙。比较三组治疗前后颌面部软硬组织变化。结果:关闭间隙前,三组患者颅颌软组织、硬组织指标比较差异无统计学意义(P>0.05),但B组鼻根点与上、下齿槽座点三者连线的夹角(ANB)大于A组、C组(P<0.05)。关闭间隙后,三组患者蝶鞍点与鼻根点,上齿槽座点三者连线的夹角(SNA)、蝶鞍点与鼻根点,下齿槽座点三者连线的夹角(SNB)、下颌平面角(SN-MP)、上中切牙内收量(U1-SN)、鼻唇角、牙冠舌向移动量(U1c-Sv)、覆盖、上颌第一磨牙近中颊尖点、近中根尖点压低量(U6c-H、U6r-H)变化值比较差异无统计学意义(P>0.05),ANB、颌平面角(SN-OP)、上颌第一磨牙内收量(U6-SN)、牙根舌向移动量(U1r-Sv)、上中切牙切缘点、牙根尖点压低量(U1c-H、U1r-H)、上颌第一磨牙近中颊尖点、近中根尖点与Sv距离(U6c-Sv、U6r-Sv)、上颌第一磨牙近中颊尖点、近中根尖点压低量(U6c-H、U6r-H)、覆(牙合)变化值比较差异有统计学意义(P<0.05);且B组ANB、Ls-E线变化值大于C组(P<0.05),A组SN-OP、U6-SN、U1c-Sv变化值大于C组(P<0.05);B组U1r-Sv、U1c-H变化值大于A组、C组,且C组大于A组(P<0.05);B组U1r-H变化值大于A组、C组,且A组大于C组(P<0.05);C组U6c-Sv变化值大于B组(P<0.05);A组U6c-H、U6r-H变化值大于B组(P<0.05);B组覆(牙合)变化值大于A组、C组(P<0.05)。结论:三种不同的微种植体支抗加力方式用于上颌前突患者均具有较好的支抗效果,可改善上颌硬组织的形态,并引起相应软组织的改变。其中,短牵引钩配合直接支抗法能明显压低磨牙、使冠远中倾斜,且(牙合)平面顺时针旋转;长牵引钩配合直接支抗法可获得更好的前牙控根移动和压低效果,且对上前牙垂直向改变效果也较好,有益于覆(牙合)控制,与短牵引钩配合间接支抗法均可获得较好的滑动内收力,稳定(牙合)平面。

深部破碎软岩巷道超前控顶加固及控制爆破技术

随着矿山开采深度逐渐增加,深部破碎围岩工程地质条件转为复杂多变,极大程度上影响巷道等工程施工过程及后续使用安全;为确保深部破碎软岩巷道施工过程中安全及质量,提出了软岩巷道超前控顶加固及控制爆破技术。针对钟九铁矿-550 m水平6号交岔点岩体裂隙极为发育、稳定性差等特点,拟采用超前控顶措施加固顶板围岩,提高深部破碎软岩巷道的承载力。为便于6号交岔点掘进施工,沿6号交岔点东北侧方向划分17个掘进区,并采用“四步”台阶法分段施工。针对同段起爆数码电子雷管,起爆器系统可随机设置单发雷管起爆间隔时间为3~5 ms,实现同段炮孔单孔单响,降低爆破振动对6号交岔点影响。根据不同掘进区总体岩性情况,优化支护方式(管棚支护、W型钢带及锚索支护等联合支护方式等),确保6号交岔点后续使用期安全。试验结果表明:采用超前控顶加固、控制分区爆破技术,降低破碎软岩巷道顶板偏帮、下沉,保证6号交岔点断面成型效果,削减其支护、后期维护等综合成本达8.7%,该技术可为类似巷道施工提供一定指导建议。

长期堆载预压处理软土地基效果评价

为评估某园区10 a长期堆载预压后,场地后续沉降对拟建管线的影响,通过室内试验和现场试验对堆载预压处理后的场地进行系统评价,分别采用双曲线法与有限元法对后续沉降进行预测。结果表明:场地堆载预压10 a后各地层物理力学参数明显改善,但其中淤泥层性质相对较差,是场地后续沉降发生的主要地层;经过10 a堆载,场地主固结沉降基本完成,固结度达到95.5%,说明长期堆载预压效果较好;对于堆载多年后的场地,在进行后续沉降数值计算时,采用弹性模型并选用现场试验获得的参数进行计算,计算结果与实测数据较好吻合,场地剩余平均沉降量在15.4 cm左右;园区道路管线可采取常规预防措施。

公立医院文化软实力评价指标体系构建

目的:探讨公立医院文化软实力的重要性及核心内涵,构建科学的公立医院文化软实力评价指标体系,为医院文化建设和高质量发展提供参考。方法:采用文献回顾法,整合文化软实力相关国内外理论与实践,初步构建公立医院文化软实力评估指标;运用德尔菲法,经两轮专家咨询后确立指标内容与层次,并应用加权平均法确定各指标权重。结果:构建了公立医院文化软实力评价体系,包括5项一级指标、14项二级指标和42项三级指标,确定了各指标权重。结论:本研究从多角度、多层次构建的公立医院文化软实力评价指标体系具有科学性和适用性,为公立医院文化软实力评估与提升提供了科学工具,对公立医院高质量发展有积极意义。

考虑湿度应力的深部软岩隧道大变形控制研究

为探明深部高地应力软岩隧道大变形产生机理,制定适应大变形控制措施,以月直山隧道为工程依托,首先明确求解围岩形变压力与松动压力的Kastner与Caquot公式,基于岩体弹塑性力学与连续介质理论建立围岩湿度应力解析解,采用收敛-约束法绘制出3种围岩应力作用下围岩与初期支护特征曲线,分析断面变形过程中围岩与支护结构相互作用规律及3种应力占比演化规律。分别以混凝土与型钢钢架作为二衬支护结构对月直山隧道围岩稳定性进行计算分析,明确考虑湿度应力与松动压力条件下隧道二衬最优支护时机与支护参数,以支护结构安全系数FS评判出最优支护方案并对隧道软岩大变形进行治理。结果表明:当围岩径向位移达到550 mm时,仅考虑形变压力Pi时围岩对支护结构的压力P仅为0.813 MPa,考虑湿度应力Pw与松动压力Pa时P增大为1.372 MPa,湿度应力与松动应力总占比达40.7%,仅考虑形变压力而设计的支护结构不满足围岩稳定性要求;根据“卸压支护”理念,确定以“位移释放峰值upeak=0.325 m”与“间距d=0.7 m”作为增设第二层钢架的最佳支护时机与支护参数,现场二次钢架设置24天后使围岩变形收敛于50.8 mm,围岩大变形得到控制,研究成果可为今后相关隧道工程设计与施工提供参考。

软测量技术赋能燃煤电厂碳排放计量的研究进展

火力发电企业作为我国能源结构的重要组成部分,长期以来是我国碳排放的主要来源,在我国和全球加速推动低碳经济发展的宏观环境下,火电企业积极响应国家“能耗双控”向“碳排放双控”转变的战略部署。在此背景下,精确计量燃煤电厂的碳排放量变得至关重要。在燃煤电厂碳计量中,烟气流量影响燃煤发电中在线监测法的精度,而燃煤消耗量、燃煤元素碳含量以及飞灰碳含量共同决定核算法的可靠性。目前,大多数燃煤发电企业只对流量和燃煤消耗量进行实时监测,在现场恶劣的环境中对燃煤元素碳含量以及飞灰碳含量进行短周期、高频次的直接监测需要花费较大的人力以及物力,流量监测设备也易受烟道环境影响。而软测量技术以其高效和低成本的特点,可为传统碳排放计量过程中关键参数的监测提供一种替代方法。鉴于此,首先阐述了软测量模型的建立过程,包含数据预处理、辅助变量选择、软测量模型建立以及模型校正。数据预处理能够确保数据质量,提高建模效率;辅助变量选择是从大量潜在的变量中筛选出对目标变量的辅助变量,进一步提高建模效率;软测量模型建立主要是基于机理建模和数据驱动建模,是实现目标变量预测的核心;模型校正通过实际的离线或在线数据,对模型进行进一步优化,提高模型的预测精度。其次,针对碳计量相关参数,分析了烟气流量、燃煤消耗量、燃煤元素碳含量和飞灰碳含量监测存在的问题,论述了软测量技术在上述碳计量关键参数的国内外研究进展和应用,评估了机理建模和数据驱动建模技术的有效性、准确性和实用性。其中,机理分析建模主要基于电厂锅炉进出口的能量平衡以及烟风质量守恒等原理,有着确定的数学物理关系式,具有高度可解释性和稳定性,但是建模过程复杂,预测精度较低;数据驱动建模主要是利用各种机器学习方法,基于电厂分布式控制系统(Distributed control system,DCS)丰富的运行数据,对碳计量关键参数进行“黑箱建模”,克服了机理分析建模复杂的过程分析,精度相对较高,但是建模过程不明确,且模型对于不同机组的泛化能力较差。最后,对于软测量技术在碳排放计量领域的发展应用进行了总结与展望。对电厂各参数之间的时序结构、电厂自身计算能力的限制以及机理分析融合数据驱动方法的发展提出相关建议,并对国外二氧化碳预测性排放系统结合软测量技术在国内外燃煤电厂的应用进行展望。

下卧软弱夹层地基ALE法强夯加固数值分析

随着高能级强夯快速发展,软弱夹层对地基加固影响问题凸显,其吸能缓冲作用机理尚不清晰,夯击参数选取经验性强。基于现场试验和任意拉格朗日-欧拉(arbitrary Lagrange-Euler, ALE)法强夯加固仿真开展地基应力波传播过程研究,探讨下卧软弱夹层对加固效果影响机理。对夯击能级、夹层埋深、夹层厚度等因素进行参数研究,改进强夯参数设计流程。结果表明:软弱夹层对夯击应力波向下传播过程有迟滞作用,地基应力场在此深度内发生断层;当首击地基加固深度为1/2软弱夹层埋深时,可兼顾能级控制与施工效率需要;当软弱夹层埋深大于10 m或厚度超过2 m时加固难度较大,需配合其他工法共同加固处理。

软土地区沉井施工引起地表沉降预测计算方法

沉井已被广泛应用于软土区的地下空间建设,但其下沉过程引起的地表沉降大小及分布不清,缺乏预测方法。本文以上海地区某沉井工程为背景,基于上海典型土层的HSS模型计算参数,采用有限差分法模拟圆形沉井下沉,基于对96个数值结果的系统分析和归一化研究,提出了一套沉井施工引起的地表沉降快速预测方法。该方法能够综合考虑沉井直径B、下沉深度H和井内留土高度h对地表沉降的影响。最后采用该计算方法预测了5个工程的地表沉降并同实测数据进行了对比,结果表明,该方法能够很好地预测软土区的沉井施工引起的地表沉降,可为快速评估沉井施工的环境效应提供有效方法。

滨海软土地基二次堆载预压固结沉降研究

滨海软土往往工程性质较差,一次堆载预压通常达不到设计要求而需要进行二次堆载预压。本文通过现场原位试验和室内试验,对二次堆载预压2年后的地基软土开展物理力学性质研究,并将试验获得的土体参数用于规范法和数值模拟,对地基未来20年的沉降进行预测。结果表明,二次堆载预压2年后,部分软土层力学参数提升显著,但淤泥层力学参数未见明显改善,地基承载力未达到设计要求,后续仍有较大的沉降变形。同时,对比规范法和研究开始前18个月沉降规律发现,经过二次堆载预压后的地基,数值模拟采用弹塑性模型能更准确地预测后续沉降,二次堆载预压20年后地基最大的沉降量可达1 m,位于12号钻孔位置处,其次是18号钻孔位置处,沉降量为0.9 m,10号钻孔位置处沉降量为0.8 m,并且沉降主要集中在淤泥层中。

有限元强度折减法分析软基边坡稳定性

有限元强度折减法在均质土坡和岩石边坡中已有较多的研究和应用,但应用到强度较低的软基边坡,其模型网格划分和边界条件,与均质边坡有所不同。经对比研究得出软基边坡模型的网格节点密度达到每米2点较为适宜,模型边界应以修正后的坡高H来界定。结合具体工程案例,利用有限元强度折减法复核其稳定,并与极限平衡法进行了对比,结果表明前述网格划分和模型边界设置较为适宜,且有限元强度折减法可以较好的反映边坡应力应变分布。