基于评标模式的公路工程造价研究

招标投标是我国工程项目进行施工承包重要的的方式。而评标的是公路工程的建设项目的招标投的标的关键环节。为了保证评标环节的公平、公正、科学、合理,保护招投标双的方的利益的,提高工程的建设的质量,研究科学、合理、有效的评标理论具有十分重的要的意义。     

阐析高速公路路基的路面施工

我国的交通运输行业的发展借助的是我国的经济的高速的发展。我国交通运输业的发展也直接带动了我国的高速公路的发展。在我国的高速公路的建设过程中,关于路基路面的施工还是存在着很多的问题的。本文针对高速公路路基路面施工的问题,来进行相关的讨论和分析,讨论高速公路路基施工中的施工工艺的应用,为高速公路的建设贡献自己的力量。     

对低压成套开关设备绝缘配合问题的探讨

电气工业的都配备有低压的成套的开关设备,我国的百分之八十左右的电能供给都是通过低压的成套的开关设备予以供出,低压的成套的开关设备的发展与工业材料制作,工艺产品和加工设备,低压的电器,人们的生活水平和基础的设施建设息息相关,所以它从一个侧面凸显了一个国家的综合国力,而其中的绝缘配合是一个关联到电气产品的安全性的至关重要的问题,应该要有非常的重视     

220kV变电站主接线运行经济性选择的探讨

变电站的主接线的设计是依据变电站的最高电压以及变电站的性质决定的。通过地区的电网的运行的实际情况出发,对220kv的变电站的主接线的运行进行了详细分析,并对变电站的主接线的设置进行了比较与分析。     

如何进行施工项目的管理和成本的控制工作

随着我国经济的不断发展,我国的基础设施的施工工程越来越多,在施工的过程中,施工项目的管理工作越来越重要。作为现代的企业来讲,施工的项目管理是非常的重要的,这主要是因为施工的企业只有做好施工项目的管理工作才能不断的完善现在的企业管理制度,使企业的管理工作更加的完善。企业只有做好施工项目的管理工作才可以提高企业的经济效益,进行项目施工的时候一定要进行必要的成本控制,这样才能够使企业的社会信誉得到提高,并且可以使企业的发展空间得到更大的提升。     

石化行业的污水处理探析

伴随着世界范围内的资源再利用的步伐,我国的石化行业的从业单位不断的发展壮大,与此同时人们的环保概念不断的在进行加强。石化行业的污水的处理方式已经越来越受到社会的关注。如何处理石化行业的污水已经是一种议题。随着我国的工业化程度的深入,我国石化行业的工业废水已经变化的多种多样,很多的化学污染物掺杂其中,这样就会对我们的化工行业的污水处理带来很多的困难。针对这种现状,我们要做的就是要不断的提升化工行业污水处理的质量和效率。本文就是针对这种问题来进行详细的论述。     

建筑施工中室外照明的接地故障保护和短路保护方法之研究

随着我们国家的经济的迅猛发展,人们的生活水平也是越来越高。人们对周围的环境的要求也是越来越严格。照明系统作为城市道路的一个明显的环节。由于室外的照明的场所的不同,所以室外照明供电系统的供电的方式也是不一样的。本文是通过对室外照明线路的选择以及供电系统的选择进行分析,为以后的室外照明的相关工程提供有利的依据。     

热电厂电气的安全使用

热电厂电气的安全使用包含的有几个方面的内容。主要分为热电厂电气主设备的安全选择、热电厂电气运行的安全管理的措施、在工作中防治电气失误操作的措施和对策以及在热电厂安全生产中的个性化和人性化的管理等等。热电厂电气的安全使用对电厂的生产以及人们的正常的生产和生活都有重要的意义,因此,本文通过对热电厂电气的安全使用的几个方面的论述来进一步说明在热电厂的工作流程中电气的安全使用所占有的重要地位。特别是在经济迅速发展的中国,在电力建设的规模不断扩大的中国,作为热电厂的一名工作人员,更是要尽自己的力量来使电厂的各方面得到快速协调的发展。通过对热电厂电气的安全使用的论述,使得热电厂向着速度更快、电容量更大、参数更高以及电网更大的方向发展。     

浅析当前公共财政政策存在的问题及对策

随着我国改革开放的不断的深入进行以及社会主义市场经济的建立和不断的完善,极大的改变了我国公共财政所面对的环境。当前我国的财政体制改革起的了很大的成功,极大的促进了我国经济的发展,但是在财政体制改革的过程当中也暴露出我国公共财政存在的一些问题。文章对当前我国公共财政存在的问题进行了深入的分析,并有针对性的提出了改进的建议,促进我国公共财政的发展。     

关于人的全面发展的探究

实现和促进人的全面发展不仅是马克思主义的一个重要理论,而且也是建设社会主义新社会的本质要求。人的全面发展的内涵应包括人的本质的全面发展、人的需要的全面发展、人的素质的全面发展和人的能力的全面发展。人的全面发展还是有其具体性、阶段性、历史性的,人的全面发展受生产力和生产关系的制约。     

设计中白与空的物自性应用研究

目的探寻设计的"物自性",研究"白"和"空"在设计中物自性的应用表现。方法通过对"物自性"本身的探究,了解其与设计本质的关系;通过追寻"白"和"空"的产生,及其在设计中的应用,了解设计中的"白"和"空"在"物自性"上的表现。结论设计中的"白"与"空"是策画的减法,而禅中的"物自性"则是生活的减法。通过研究"物自性"及其与设计的关系,发现设计原本并不是为了要给世界增添什么新的额外的东西,它可能只是回归到了原始的状态,通过物体本身展现其本质的一面。清理多余的杂乱后出现的"白"与"空",不再是无意义,而是一种不存在的强烈存在,是一种全新意义上的创新性表现。     

Stratified media theory interpretation of measurements of the spectral polarized directional emissivity of some oxidized metals

The emissivities of metals are strongly affected by the growth of oxide films. For small film thicknesses, perturbations are limited to the visible range. As thicknesses increase, they spread to the infrared range. Various samples of optically polished metals (Fe, Ni, Cr) and stainless steels (ELI.T 1803 MoT and AISI 304 or 316) have been oxidized at temperatures ranging from 400 to 800C. Their spectral polarized directional emissivities, and , have been measured with two experimental techniques. The spectral range studied extends from 0.4 to 14 m; the measurement directions vary between 0 and 80 from the normal to the sample. After measurement, each sample was analyzed by glowdischarge optical spectroscopy (GDOS). From the results of the analysis and from the survey of bibliographical data, we characterized the structure of the oxide films, i.e., their approximate thicknesses and compositions. If the complex optical indices of the metals and oxides are known, the stratified media theory enables the computation of the emissivities and . Computed and measured values have been compared. It appears that the theory accounts well for experimental data when the thicknesses of the oxides are small as in stainless steels. But for thicker oxide films, discrepancies are ascribed to several reasons.     

Effect of phase fluctuations upon penetration depth

The temperature dependence of the static penetration (T) has been used as a guide to the nature of the superconducting state in high-T _c materials. It has been argued that an algebraic temperature dependence in the ratio (T)/(0) [(T) — (0)]/(0) at low temperature is evidence for d-wave pairing. This paper examines the effect of superconducting phase fluctuations upon (T) and finds an algebraic dependence over a broad range of temperature.     

Interfacial spring model for ultrasonic interactions with imperfect interfaces: Theory of oblique incidence and application to diffusion-bonded butt joints

The quasi-static distributed spring model is used to derive the ultrasonic reflectivity of an imperfectly-bonded interface as a function of frequency and angle of incidence. The results are then incorporated in a model for the corner reflection from a diffusion-bonded joint between two abutting plates, the corner being defined by the bond plane and the common lower surface plane of the plates. An immersion-inspection geometry is assumed, and seven categories of corner reflections are identified and examined in detail. These fall into two classes: those having parallel incident and exiting rays in water (=), and those having nonparallel water rays ( ). The = categories are suitable for single probe (pulse-echo) inspections of the joint. Based on the amplitude of the outgoing corner-reflected signal, two = geometries appear promising. These employ, respectively, a corner reflection involving only longitudinal waves with the interface illuminated at near-grazing incidence (LLL), and a corner reflection involving only transverse waves with the interface illuminated at near 45° incidence (TTT). In addition, two practical geometries are indicated; these both involve mode conversion upon reflection from the interface, with the incident or outgoing longitudinal wave traveling nearly parallel to the interface. Model predictions for LLL and TTT reflections are compared to measurements on diffusion-bonded Inconel specimens, and techniques for applying the model results to more complicated bond geometries are discussed.     

Viscoelastic and rheological behavior of concentrated colloidal suspensions

Molecular approaches are discussed to the density (), viscoeleastic (), and rheological () behavior of the viscosity(,,) of concentrated colloidal suspensions with 0.3 < < 0.6, where, is the volume fraction, the applied frequency, and ; the shear rate. These theories are based on the calculation of the pair distribution functionP ₂(r,,), wherer is the relative position of a pair of colloidal particles. The linear viscoelastic behavior(,,=0) follows from an equation forP ₂(r,,) derived from the Smoluchowski equation for small, generalized to large by introducing the spatial ordering and (cage) diffusion typical for concentrated suspensions. The rheological behavior(,,=0) follows from an equation forP ₂(r,) of a dense hard-sphere fluid derived from the Liouville equation. This leads to a hard-sphere viscosity^hs(,) which yields the colloidal one(,) by the scaling relation(,) ₀=^hs(,) _B, where ₀ is the solvent viscosity. _B is the dilute hard-sphere (Boltzmann ) viscosity and the's are appropriately scaled,(,) and(,) agree well with experiment. A unified theore for(,,) is clearly needed and pursued.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994. Boulder, Colorado, U.S.A.     

Flame quenching through endothermic reaction

A laminar premixed flame model is considered in which there is a second-order branching reaction coupled with an endothermic decay of a chemical inhibitor. An analysis, based on high activation energies for the reactions, is performed and two distinct cases are found. These depend on dimensionless parameters representing the loss of heat relative to its production, , and the consumption of inhibitor relative to that of fuel, . With 1, extinction is achieved through a saddle-node bifurcation at a critical value of . For , no extinction is found though considerable reductions in wave speed over the adiabatic limit are seen. The asymptotic results are compared with numerical simulations of an initial-value problem for the model.     

Elevated temperature deformation behaviour of multi-phase Ni-20 at % Al-30 at % Fe and its constituent phases

The mechanical behaviour of the multi-phase ( + /) alloy Ni-20 at % Al-30 at % Fe and alloys similar to its constituent and / phases, Ni-30 at % Al-20 at % Fe and Ni-12 at % Al-40 at % Fe, respectively, were investigated. When tested in tension at 300 K, the alloys exhibited 20%, 2% and 28% elongation, respectively. At elevated test temperatures (700, 900 and 1100 K), the multi-phase alloy exhibited increased ductility, reaching an elongation in excess of 70% at 1100 K without necking or fracture. Similarly, the alloy demonstrated increased ductility with increasing test temperatures. In contrast, the / alloy showed greatly reduced ductility with increasing temperature and was quite brittle both at 900 and 1100 K. Thus, whilst at room temperature the / phase improved the ductility of the + / aggregate, at elevated temperatures the phase alleviated the brittleness of the / phase, thereby preventing any embrittlement of the multi-phase alloy over the temperature range 300–1100 K. Also, whilst the phase improved the room-temperature strength of the multi-phase alloy, at elevated temperatures where the phase is known to be weak, the / phase improved the strength of the multi-phase alloy up to 900 K, beyond which the strength deteriorated due to disordering and lack of anomalous strengthening in the / component.     

Analysis of a transiently propagating crack in functionally graded materials under mode I and II

Crack tip stress and displacement fields for a transiently propagating crack along gradient in functionally graded materials (FGMs) with a linear variation of shear modulus are developed. The higher order terms of the transient stress and displacement fields at crack tip were obtained by transforming the general partial differential equations of the dynamic equilibrium into Laplace’s equations whose solutions have harmonic functions. Thus, the fields can be expressed very simply. Using these stress components, isochromatics and the first invariant at crack tip are generated.The results show that the isochromatics (constant maximum shear stress) for mode I crack tilt backward around the crack tip with an increase of crack tip acceleration , and tilt forward around the crack tip with an increase of rate of change of dynamic mode I stress intensity factor . The isochromatics for mixed mode crack move to upper direction with an increases of and , and lower direction with an increase of . Contours of the first stress invariant for mode I crack enlarge around the crack tip with an increase of , and decrease around the crack tip with an increase of . As decreases at crack initiation, the predicted kinking angles increase. As increases, the predicted kinking angles also increase.