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441.
This article focuses on the implications of the recently developed commutative formulation based on branch-cutting cosmology, the Wheeler–DeWitt equation, and Hořava–Lifshitz quantum gravity. Assuming a mini-superspace of variables, we explore the impact of an inflaton-type scalar field ϕ ( t ) $$ \phi (t) $$ on the dynamical equations that describe the trajectories evolution of the scale factor of the Universe, characterized by the dimensionless helix-like function ln 1 [ β ( t ) ] $$ {\ln}^{-1}\left[\beta (t)\right] $$ . This scale factor characterizes a Riemannian foliated spacetime that topologically overcomes the big bang and big crunch singularities. Taking the Hořava–Lifshitz action as our starting point, which depends on the scalar curvature of the branched Universe and its derivatives, with running coupling constants denoted as g i $$ {g}_i $$ , the commutative quantum gravity approach preserves the diffeomorphism property of General Relativity, maintaining compatibility with the Arnowitt–Deser–Misner formalism. We investigate both chaotic and nonchaotic inflationary scenarios, demonstrating the sensitivity of the branch-cut Universe's dynamics to initial conditions and parameterizations of primordial matter content. The results suggest a continuous connection of Riemann surfaces, overcoming primordial singularities and exhibiting diverse evolutionary behaviors, from big crunch to moderate acceleration.  相似文献   
442.
This article focuses on the implications of a noncommutative formulation of branch-cut quantum gravity. Based on a mini-superspace structure that obeys the noncommutative Poisson algebra, combined with the Wheeler–DeWitt equation and Hořava–Lifshitz quantum gravity, we explore the impact of a scalar field of the inflaton-type in the evolution of the Universe's wave function. Taking as a starting point the Hořava–Lifshitz action, which depends on the scalar curvature of the branched Universe and its derivatives, the corresponding wave equations are derived and solved. The noncommutative quantum gravity approach adopted preserves the diffeomorphism property of General Relativity, maintaining compatibility with the Arnowitt–Deser–Misner Formalism. In this work we delve deeper into a mini-superspace of noncommutative variables, incorporating scalar inflaton fields and exploring inflationary models, particularly chaotic and nonchaotic scenarios. We obtained solutions to the wave equations without resorting to numerical approximations. The results indicate that the noncommutative algebraic space captures low and high spacetime scales, driving the exponential acceleration of the Universe.  相似文献   
443.
面板堆石坝的坝料开挖直接制约工程进度,按传统工艺开挖费时费工,严重影响施工进度,本工程在利用坝体级配料开挖中采用爆破直采技术,加快了坝料开采速度,效果显著。经过爆破试验,优选爆破参数,为获取粒径与级配符合设计要求及成本低廉的坝料创造了有利条件。详细介绍了试验过程,并对试验结果进行了分析。  相似文献   
444.
文章论述在斜井掘进中采用定向控制爆破技术 ,利用最小抵抗线原理 ,即最小抵抗线方向是爆破作用和岩石移动的主导方向 ,使石渣向后抛掷 ,以充分利用耙斗装岩机工作 ,从而大大提高工作效率 ,降低工人的劳动强度。  相似文献   
445.
冻土位移的散斑照相测量   总被引:1,自引:0,他引:1  
武建军  俞祁浩 《冰川冻土》1997,19(3):258-262
针对冻土受力变形的特性,给出了白光散斑照相,激光散射照相和激光显微散照相技术相结合测量冻土位移的方法,分析讨论了各种散斑照相的测量范围,对冻土弹性变形范围内的位移测量实验表明,这是一种有效的测量手段。  相似文献   
446.
Summary A variety of overbreak control techniques are used during excavation with the drill and blast system. Tracer blasting is used in Canadian underground mines to minimize blast damage and involves placing a low-strength detonating cord along the length of a blast hole prior to charging with ammonium nitrate-fuel oil (ANFO). The results of tracer blasting are not always consistent and its mechanism is only hazily comprehended. In the absence of a clearly defined mechanism, it is difficult to analyse the results of tracer blasting and to identify the factors responsible for the inconsistency of results.A series of bench blasts and pipe tests were carried out to investigate the mechanism of tracer blasting. The evidence indicated partial deflagration and desensitization of ANFO, thus reducing the total available explosive energy. The rock mass surrounding the traced blasthole experienced a low level of ground vibrations. As a result of the continuous side initiation of ANFO, energy partitioning was more in favour of gas energy. A mechanism of tracer blasting has been proposed and the factors responsible for the inconsistency of the results have been identified in this paper.  相似文献   
447.
分析了水下爆炸夯实基床的基本原理及作用机理,并应用于海南和帮码头基床的爆夯,取得预期的效果,表明基床的水下爆夯法有效,可行,具有广阔的应用前景。  相似文献   
448.
详细论述了齐齐哈尔市中华路立交桥爆破拆除施工中所遇到的各种技术问题及解决办法。  相似文献   
449.
介绍了黑火药控制爆破法在河南省商城县花岗岩开采中的试验与应用,给出了工作面开采要素和合理的爆破参数。  相似文献   
450.
结合大型开山工程的实际,总结了设备选型和施工,管理技术,从合理布设穿孔间距,防滚石下海,地平面保护等方面控制台阶爆破质量,并介绍了台阶爆破的安全控制措施。  相似文献   
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