越南岘港—广义高速公路路基压实效率控制要点

主要介绍了越南路基施工规范和中国路基施工规范的异同,结合越南岘港至广义高速公路A3标段路基施工压实效率控制经验,提出针对越南当地炎热环境下路基素土填方压实效率控制要点进行分析总结,提出在满足压实要求过程中,优选土源,合理利用土的天然含水量和压实设备的压实功,提高土方压实效率的措施,供类似工程施工参考。

我国金融“脱虚向实”效率及影响因素研究——基于动态异质性随机前沿模型的分析

文章基于我国31个省、自治区、直辖市2011年—2020年的面板数据,利用动态异质性随机前沿模型测算金融“脱虚向实”效率并分析其影响因素。研究发现:金融机构存贷款余额的增长可以有效推动金融“脱虚向实”,社会融资规模的扩大并未对实体经济增长产生有效的拉动作用,当前金融对实体经济的支持效率还处于较低水平,且金融资产配置失衡致使金融市场发展程度和银行集中度的提高会对实体经济产生不利影响。今后可通过继续坚持金融创新、不断深化金融改革等措施提高我国金融“脱虚向实”效率。

双频双幅合成振动压实方法

为了提高压实质量和压实效率,提出了一种双频双幅合成振动压实方法,介绍了这种压实方法的基本原理和前3轮试验样机的设计方案及试验结果,认为双频振动压实机设计的主要参数是两频率比、两振幅比、两频率相位差和激振器初始安装角,应综合考虑它们对压实过程的影响。研究结果表明,与传统的单频振动压实方法相比较,双频双幅合成振动压实方法的主要特点是压实度较高,压实效率较高,对多种材料的适应性好,但需要的振动功率增大。

双频合成振动压实方法的探析

依据双频合成振动压实的基本原理,进行了双频合成振动压实的实验分析,认为双频振动压实机设计的主要参数是两频率比、两振幅比、两频率相位差及激振器初始安装角。研究证明,与传统的单频振动压实方法相比,该方法的主要特点是压实度和压实效率较高。

路基压实状态固有频率特性与土体不同高度关系试验研究

该文通过试验研究,得到路基压实状态固有频率特性与土体不同高度关系。结果表明,不同高度各土样加速度时程曲线变化基本一致,不同高度土体各自的峰值加速度差异较大,呈非线性变化趋势。锤击力为235 N时,土样自振频率处于10~25 Hz宽频带之间。基于共振原理,当系统受到与本身固有频率相同的强迫振动时,系统振幅达到最大,从而产生“共鸣”,此时压实效果最好。因此在振动压实碾压作业时,选取合适的振动频率对于提高压实效率十分重要。

探索高效的计算机上机实训方法(一)——计算机文化基础For Windows 2000

计算机文化基础这门课程是所有大学新生都要学的基础课程 ,如何提高这门课程的上机实训效率 ,本人在对近千学生的教学对比实践中 ,从科学合理安排实训内容、灵活调整不同学生的学习进度等几方面入手 ,初步探索出了一套行之有效、操作性很强的方法 ,供同行们参考并提出改进意见。

鄂尔多斯盆地南部镇泾油田前侏罗纪古地貌与油层分布规律

通过大量的岩心观察、铸体薄片、物性测试、测井资料解释等,用印模法编制了镇泾油田前侏罗纪古地貌图。通过分析古地貌与上覆地层延9的沉积相展布、构造格局及下伏长6的储层特征,认为延9的沉积相展布完全受控于前侏罗纪古地貌,辫状河道自高地经缓坡从山谷流出,北边河流有支流汇入南边河流;延9构造均为差异压实形成,高地和山脊易形成幅度较大的背斜构造;剥蚀面之下的长6储层物性明显受控于淋滤作用的改造程度,淋滤作用愈强、蚀变产物易带走,则储层具有较好的物性,而淋滤作用的改造程度和蚀变产物的易带走程度也完全受古地貌的控制,山谷为淋滤带最发育区。剥蚀面之上的延9油层主要受构造和砂体的控制,油层分布于高地和山脊;而剥蚀面之下的长6油层主要受控于淋滤带的改造程度,油层主要分布于山谷。

代码Cache分组管理策略研究

代码Cache是动态优化系统的重要组成部分,利用代码Cache可以实现翻译代码的复用,利用软件管理代码Cache存储优化和代码翻译。代码Cache存储大小不等的超级块,超级块之间可能包含指向其它超级块的链接指针,因而会带来较高的替换开销。提出采用分组管理代码Cache的策略,该策略能够有效的平衡Cache管理的复杂性和Cache的失效率。

冲击式压路机及其应用

冲击式压路机是继光轮压路机和振动压路机之后出现的新型压路机 ,它凭借巨大的冲击能量和相当高的行驶速度可获得深层压实效果和极高的压实效率 ,在公路、铁路机场路基处理中得到了日益广泛的应用。阐述了冲击式压路机的工作原理、特点及应用。

Multiple attenuation using λ–f domain high-resolution Radon transform

The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the 2- fdomain high-resolution Radon transform based on the fast and modified parabolic Radon transform presented by Abbad. The introduction of a new variable 2 makes the transform operator frequency-independent. Thus, we need to calculate the transform operator and its inverse operator only once, which greatly improves the computational efficiency. Besides, because the primaries and multiples are distributed on straight lines with different slopes in the 2-fdomain, we can easily choose the filtering operator to suppress the multiples. At the same time, the proposed method offers the advantage of high-resolution Radon transform, which can greatly improve the precision of attenuating the multiples. Numerical experiments suggest that the multiples are well suppressed and the amplitude versus offset characteristics of the primaries are well maintained. Real data processing results further verify the effectiveness and feasibility of the method.

Studies on Recovery Efficiencies of Phenols from Phenol Fraction Using Alkali Treatment

Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Plant, Visakhapatnam whose composition is known. The phenol fraction from coal tar distillate can be treated for extracting phenols using caustic soda. An attempt has been made to find out whether the existing practice of using only 8%-15% can be modified by increasing the strength of sodium hydroxide and also explore the possibilities of substituting the sodium hydroxide with KOH as an extractant. The different streams of liquids obtained during experimentation have been analyzed by gas chromatograph. Salient features of the study are that higher concentrations of the alkali significantly improved the separation efficiencies of phenols and also regenerate the phenolate with higher phenol content. Increase in the alkali strength has greatly improved the separation as well as the phenol content in the regenerated phenols. Disposal of effluents containing phenols may lead to environmental problem of ground water pollution and the study throws a light on the removal of phenols from the effluents to the extent possible by using higher strength alkali solutions.

Simulation experiments on counter beam lighting in highway tunnel

Counter beam lighting was introduced as well as transverse symmetrical lighting and longitudinal symmetrical lighting.Simulation experiments were carried out by using DIAlux lighting software for the above three lighting methods.The results show that counter beam lighting is more reasonable to be adopted in the tunnel entrance zone because its threshold increment of disability glare is greater.Counter beam lighting can improve the background luminance of the obstacles and lighting efficiency compared with transverse symmetrical lighting and longitudinal symmetrical lighting.Therefore,tunnel lighting energy-saving can be achieved by reducing the road luminance demands and luminaries power.Longitudinal symmetrical lighting is conducive to the large luminaries spacing in the tunnel internal zone;so power consumption can be reduced by decreasing the number of luminaries used.Tunnel walls are unsuitable to pave with smooth or bright material.Installation height of the luminaries has less effect on counter beam lighting.

Treatment performance of integrated biological aerated filter by orthogonal experiments

Biological aerated filters have many advantages such as small volume and high treatment efficiency. This research focused on sewage treatment performance of integrated biological aerated filter (IBAF) under different conditions such as aeration, hydraulic retention time and the height of fillers layer, to identify the turn of marked affecting factor of removal performance through orthogonal experiments, optimize the function parameter of IBAF, reveal the regularity of sewage treatment of IBAF under different conditions, and adopt suitable measures to guarantee excess water quality of IBAF.

Experimental study of water effects on gas desorption during highpressure water injection

For the question of applying high-pressure water injection to increase gas extraction efficiency by increasing the permeability of water to drive gas action, an independently designed gas desorption experimental measuring device was used under the condition of external solution invasion. The law of water effect on gas desorption was obtained after water invasion through experiment for the first time. The results show that water＇s later invasion not only can make the quantity of gas dcsorp- tion greatly reduced, but also can make gas desorption end early. Therefore, when evaluating the applications of high-pressure water injection to increase gas extraction efficiency, we should take water damaging effects on gas desorption into account.

The Effect of Stocking Density on the Behaviour and Welfare Indexes of Broiler Chickens

The effect of three stocking densities, ranging from 30 to 44 kg product per m2 on the performance, behaviour and welfare indexes in broiler chicken was investigated. Scan sampling for comparative behavior in all groups was carried out at 2 min intervals during 2-20 min periods for five days each week. It was found that the most common behaviour in all densities was lying （resting）, lying and standing behaviour was tended to increase in H than L group of all experimental period. Pecking behaviour was not constantly changed by stocking density. Locomotion was not only reduced with increasing age but increase stocking density of all experimental period and all groups. Body weight gain and feed efficient were, tend to increase in L than H group of 2 to 3 weeks ages, higher in L than H group （P 〈 0.05） of 4 to 5 weeks ages and all experimental period. Other behaviours （dustbathing, preening, eating or drinking） were not influenced （P 〉 0.05） by stocking density. It seems that gait, foot pad and hock burn score were improved in L than H group of 35 days age （P 〈 0.05）. The claw length of 21 days age was not affected by stocking density, but it was significantly different by stocking density of 35 days age （P 〈 0.05）. The duration of tonic immobility （TI-reaction） was tended to decreased age of 21 than 35 days, but not effected by stocking density. These data indicate that stocking density can influence broiler behaviour and welfare indexes.

Characteristics analysis of a novel centralized-driving flip-flow screen

During screening operation, blinding or clogging of screen perforations generally occurs to reduce the sieving capacity and efficiency. Recently, the flip-flow screening has been widely recognized as a feasible method to deal with the problem. In this paper, a novel centralized-driving flip-flow screen(CFS) was developed for the separation of fine and moist coal, and the key structures, namely, a centralized-driving mechanism and a quasi-circle beam mounted with the mat were designed for high reliability and stability. By means of a test on an experimental prototype, the effect of some factors, i.e., initial stretch and hardness of the polyurethane panel, respectively, and the rotation speed of the driving motor on the kinematic characteristic of the screen surface was investigated. Results show that without an initial stretch, the sieve mat generates the largest vibratory amplitude while the slacker the sieve mat initially is, the smaller amplitude it will accomplish. And an increase in the rotation speed could cause a rise in the vibratory amplitude. Unlike the two factors, the hardness does not have a definite effect on the kinematic performance, on which a further study is required. Finally, screening processing on a laboratory prototype was conducted to draw the conclusion that the developed CFS also has a high sieving efficiency for the fine and moist coal.

Cross-Layer Scheduling Design for Multimedia Applications over Cognitive Ad Hoc Networks

In this paper,we study cross-layer scheduling scheme on multimedia application which considers both streaming traffic and data traffic over cognitive ad hoc networks.A cross-layer design is proposed to optimize SU's utility,which is used as an approach to balance the transmission efficiency and heterogeneous traffic in cognitive ad hoc networks.A framework is provided for utility-based optimal subcarrier assignment,power allocation strategy and corresponding modulation scheme,subject to the interference threshold to primary user(PU) and total transmit power constraint.Bayesian learning is adopted in subcarrier allocation strategy to avoid collision and alleviate the burden of information exchange on limited common control channel(CCC).In addition,the M/G/l queuing model is also introduced to analyze the expected delay of streaming traffic.Numerical results are given to demonstrate that the proposed scheme significantly reduces the blocking probability and outperforms the mentioned single-channel dynamic resource scheduling by almost 8%in term of system utility.

Simulation Study on Purification Efficiency for Nitrogen in Different Types of Wetlands in Sanjiang Plain, China

The purification law of nitrogen in Deyeuxia angustifolia, Carex lasiocarpa and Deyeuxia angustifolia-Carex lasiocarpa combined wetland systems in the Sanjiang Plain, China was studied by field simulation experiment. The results indicate that the removal rates of TN, NH4^＋-N and NO3^--N in above three types of wetlands present an obvious logarithm growth trend along with the time. There are evident removal effects for NH4＋-N and NOa--N in water bodies of wetlands after the 30th day of experiment, with the removal rates over 80.0%, but the removal rate of TN is slightly low, being 63.1%-74.3%. NO3 -N is most quickly removed by the combined wetland, and NH4^＋-N by Deyeuxia angustifolia wetland. The removal speeds of TN by the three wetland systems are comparatively slow, of which the Deyeuxia angustifolia wetland is the fastest. In consideration of plant growth season, Deyeuxia angustifolia wetland has much more practical application value in purifying nitrogen. These results can provide references for the study on the purification function of wetlands and the control of non-point source pollution in Northeast China.

Design of a new bionic diamond bit and its experimental study

Bionics was applied in the design of the impregnated diamond bit. Based on previous resehrch and the 63# bit matrix formula, a new non-smooth bionic impregnated diamond bit with a single circular ring was designed and manufactured, and also tested indoor. The results were satisfactory. During its shape contacted surface system, non-smooth shape display some structure merits such as decreasing resistance. It was obvious that the drilling efficiency of the bionics bit is much higher than that of ordinary＇s one, and so does the working life of bionic bit.