光面爆破在云鹏电站坝肩开挖中的应用

在云鹏电站大坝工程坝肩施工中采用了梯段爆破及光面爆破，并取得了预期的效果。本文着重介绍了光面爆破在软岩中的爆破参数设计，并对爆破效果进行了分析。     

用台阶深孔爆破漏斗试验确定爆破参数

露天矿爆破工程是首要开采工序，合理的爆破参数确保爆破质量要求，通过台阶深孔爆破漏斗试验法确定合理的爆破参数较其它方法精确，简便和直观，因而是切实可行的。     

在孔距爆破机理浅析及在工程上的应用

大孔距爆破在世界各国应用很广泛，本文旨在前人研究的基础上对大孔距爆破机理做进一步的分析，在此重点探讨大孔距爆破在我国露天矿工程中的应用，依据此机理设计出一种台阶爆破网路为露天矿生产的参考。     

三十亩地选矿厂1^#球磨机传动基础控制爆破拆除实践

通过球磨机基础控制爆破拆除实践，从分析钢筋混凝土爆破破坏形态出发，钢筋层数等对拆除爆破的影响作了量化处理，在药量计算中，把复杂的钢筋混凝土复合介质转化为混凝土单一介质，并在本次爆破工程实际中得到验证。     

我国工程爆破技术研究及应用进展 --全国第七届工程爆破学术会议综述

根据全国第七届工程爆破学术会议情况，对我国近四年来在工程爆破技术理论研究及工程实践方面取得的成果和进展，作一综合概述。     

三十亩地选矿厂1~#球磨机传动基础控制爆破拆除实践

通过球磨机基础控制爆破拆除实践，从分析钢筋混凝土爆破破坏形态出发，钢筋层数等对拆除爆破的影响作了量化处理，在药量计算中，把复杂的钢筋混凝土复合介质转化为混凝土单一介质，并在本次爆破工程实际中得到验证。     

水土围压爆破拆除混凝土薄壁池体

从常见的钢筋混凝土薄壁池体的爆破拆除工程出发，指出了水压爆破和钻眼爆破法的缺陷，提出了更适合于薄壁池体的新方法——水土围压爆破；同时对如何确定爆破参数进行了较详尽的论述。通过工程实例，进一步证明了该方法的可行性。     

探讨工程爆破技术在矿山开采中的运用

矿山开采中工程爆破技术的应用较为广泛,但受到不断增加的矿山开采工程复杂系数影响,工程爆破技术应用正面临新的挑战。基于此,本文简单介绍常用的工程爆破技术,并结合实例深入探讨工程爆破技术的具体应用,以供业内人士参考。     

模糊决策方法在光面爆破中的应用

光面爆破技术是集岩石力学、井巷工程、固体力学、爆破力学、断裂力学于一身的一门复杂学科，学起来困难大。所以，在具体的光面爆破工程中，爆破技术人员往往不是领先理论，而是凭经验确定爆破参数和爆破方案。而爆破是一个复杂的系统工程，如果对其参数不做科学的评价，没有科学的决策方法，往往会出现不可推测的结果。本文在国外著名专家学者的重要论断和实验结果的基础上，总结了一套切实可行的常用光面爆破方案的模糊决策方法，在光面爆破工程中能帮助爆破技术人员对光爆方案做出科学的选择。这种模糊决策方法已经在拆除爆破工程中得到应用，并取得了良好的效果。     

浅析凿岩爆破对矿山生产经济效益的影响

单纯降低凿岩爆破的直接成本，而忽视爆破效果不良所造成的掘进效率低，矿石大块率，贫化与损失率提高等，将给生产带来较大的经济损失，金岭铁矿加强爆破工程管理，提高职工技术水平和思想素质，保证爆破效果，提高了矿山的经济效益。     

Investigation of the Hammerstein hypothesis in the modeling of electrically stimulated muscle

To restore functional use of paralyzed muscles by automatically controlled stimulation, an accurate quantitative model of the stimulated muscles is desirable. The most commonly used model for isometric muscle has had a Hammerstein structure, in which a linear dynamic block is preceded by a static nonlinear function. To investigate the accuracy of the Hammerstein model, the responses to a pseudo-random binary sequence (PRBS) excitation of normal human plantarflexors, stimulated with surface electrodes, were used to identify a Hammerstein model but also four local models which describe the responses to small signals at different mean levels of activation. Comparison of the local models with the linearized Hammerstein model showed that the Hammerstein model concealed a fivefold variation in the speed of response. Also, the small-signal gain of the Hammerstein model was in error by factors up to three. We conclude that, despite the past widespread use of the Hammerstein model, it is not an accurate representation of isometric muscle. On the other hand, local models, which are more accurate predictors, can be identified from the responses to short PRBS sequences. The utility of local models for controller design is discussed.     

Transformation of the Sandler and Rubin Nonsmooth Cap Model to the Pelessone Smooth Cap Model

The Sandler and Rubin cap model is the most popular cap model that is able to take account on geomaterial dilation and compaction effects. However, its nonsmooth yielding surface often results in a slow convergent rate or even nonconvergent solution in some numerical simulations. More often, analysts with the Sandler and Rubin model have to switch to a smooth cap model, for example, the Pelessone model, in order to obtain a convergent solution. For cases of original experimental data available direct fitting is the best way for obtaining the required smooth model parameters. For cases of only derived nonsmooth model parameters available, a transformation from nonsmooth models to smooth models is necessary. However, such a transformation is nontrivial. In this paper, we propose two simple and robust methods for transferring the Sandler and Rubin nonsmooth model to the Pelessone smooth model through making a few reasonable assumptions and solving only one nonlinear equation for one primary unknown. Two model examples are presented to demonstrate the good performance of our proposed methods.     

An analytical model for the prediction of the transfer bar temperature in a roughing mill

Abstract

An online model is presented for the prediction of temperature distributions in the bar in the roughing mill of a hot strip mill. The model consists of an analytic model for the prediction of temperature distributions in the interstand zone, and a semianalytic model for the prediction of temperature distributions in the bite zone. The prediction accuracy of the model is examined through comparison with predictions from a finite element model.     

Interpreting the equatorial diffraction pattern of collagenous tissues in the light of molecular motion

The equatorial diffraction pattern associated with collagenous tissues, particularly type I collagen, is diffuse and clearly unlike that from crystals. Hukins and Woodhead-Galloway proposed a statistical model that they termed a "liquid crystal" for collagen fibers in tendons. Fratzl et al. applied this model to both unmineralized and mineralized turkey leg tendon, a model that ignores the organization imposed by the well-known cross-linking. The justification for adopting this model is that the curve fits the data. It is shown that the data can be equally well matched by fitting a least-squares curve consisting of a second-order polynomial plus a Gaussian. The peak of the Gaussian is taken as the equatorial spacing of the collagen. A physical explanation for this model is given, as is a reason for the changes in the spacing with changes in water content of the tissue. The diffusion is attributed to thermally driven agitation of the molecules, in accordance with the Debye-Waller theory including the Gaussian distribution. The remainder of the diffusion is attributed to other scattering sources like the mineral crystallites.     

On the validity of the Vroom-Yetton model.

Reports an empirical evaluation of the validity of the Vroom-Yetton contingency model of leadership behavior (V. H. Vroom and P. W. Yetton, 1973). Naive to the model, 96 managers from a variety of organizations described 181 actual problem-solving or decision-making situations and their behavior in these situations. The model was then employed to predict ratings of the technical quality, subordinate acceptance, and the overall effectiveness of the final solutions chosen or decisions made. Substantial support for the model and its various components was obtained. Its concurrent validity was greater than that of a noncontingent model proposed by other theorists. The validity of the Vroom-Yetton model is due, in large measure, to relationships between agreement with the model and subordinate acceptance of or commitment to decisions. Relationships with decision quality were smaller. Reasons for this difference and possible deficiencies of the model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a Full Simulation of the Basic Oxygen Furnace: Deformation of the Bath Free Surface and Coupled Transfer Processes Associated with the Post-Combustion in the Gas Region

The present article treats different phenomena taking place in a steelmaking converter through the development of two separate models. The first model describes the cavity produced at the free surface of the metal bath by the high-speed impinging oxygen jet. The model is based on a zonal approach, where gas compressibility effects are taken into account only in the high velocity jet region, while elsewhere the gas is treated as incompressible. The volume of fluid (VOF) method is employed to follow the deformation of the bath free surface. Calculations are presented for two- and three-phase systems and compared against experimental data obtained in a cold model experiment presented in the literature. The influence on the size and shape of the cavity of various parameters and models (including the jet inlet boundary conditions, the VOF advection scheme, and the turbulence model) is studied. Next, the model is used to simulate the interaction of a supersonic oxygen jet with the surface of a liquid steel bath in a pilot-scale converter. The second model concentrates on fluid flow, heat transfer, and the post-combustion reaction in the gas phase above the metal bath. The model uses the simple chemical reaction scheme approach to describe the transport of the chemical species and takes into account the consumption of oxygen by the bath and thermal radiative transfer. The model predictions are in reasonable agreement with measurements collected in a laboratory experiment and in a pilot-scale furnace.     

Simulation of the mechanical properties of nanostructured porous ceramics

A nonclassical model is developed to describe the deformation of nanostructured ceramics. The model takes into account the scale effects and can be used to determine the effective elastic moduli of such ceramics with allowance for the grain size, the damage level (porosity), and the adhesion parameters characterizing the intergrain contact quality. This model is based on a particular version of the gradient theory of defective media, in which the free strain tensor is determined by the free volume change strains and the continuum model of adhesion interactions is consistent with a chosen kinematic model. The effective characteristics of ceramics are determined with the gradient cohesion-adhesion model using the modified three-phase Eshelby method. Examples of simulating the effective elastic moduli are given, and they demonstrate the efficiency of the model and its adequacy to the well-known experimental data.     

Epigenetic stratification: the role of individual change in the biological aging process

Aging is a complex process. It consists of a diverse assortment of seemingly random manifestations that occur in the individual, the mutual relationship and impact on mortality of which is frequently obscure. We derive a simple equation to model the aging process based on scale invariant and increasing change. The solution to this equation indicates that this change itself, irrespective of its quality, is the cause and not simply the effect of aging. This model establishes loss of homeostasis as a fundamental feature of aging. The model is deterministic, but it supports the stochastic nature of age changes. Paradoxically, this model states that a sufficient augmentation of aging processes results in a lack of aging. Experimental evidence in support of this model is presented that spans the levels of population mortality rates, cellular spatial organization, and gene dysregulation.     

Integrity of the pericardium. Its beneficial effects on the protection of the right ventricle in the presence of acute pulmonary hypertension

After cardiac transplant (CT), the right ventricle can be subject to an acute pressure overload, especially in cases where there is a pre-existing severe pulmonary hypertension. Objectives: To determine the maximum tolerance of the right ventricle (MxTRV) when faced with acute pressure overload. To study the function of both ventricles of the healthy heart (donor) when faced with different degrees of pulmonary hypertension. To detect possible interactions between the ventricles in the absence of the pericardium to approximate the experimental model to the clinical model of CT. Methods: The pulmonary artery is progressively constrained in an experimental model until biventricular failure is detected. This experiment is performed in two different situations: with and without pericardial integrity. Results: When pericardial integrity is maintained the MxTRV faced with a pressure overload is 73.2+/-8.56 mmHg. When this pressure is exceeded there is a circulatory collapse with a sharp fall in the cardiac output and in the aortic pressure. However, when pericardectomy is performed (model similar to CT), only 52+/-6.71 mmHg is tolerated (p< 0.001). Conclusions: With the pericardium open, as in CT, the maximum pressure that the right ventricle can support is significantly less than with the pericardium closed. The pericardium has a positive effect in protecting the systolic ventricular interaction.