介绍一种新型高深度表——兼谈地图上陆高与海深的表示

地图上陆高均以平均海水面起算,平均海水面称为高程基准面,此面以上为陆地高程,以下为陆地负高程。海洋中的水深,则以深度基准面起算,此面以下为海深,以上为干出高度。尽管这两个基准面之间相差仅1—2米,相对于几百米乃至几千米的高差来说,可算是微乎其微,但毕竟不是统一的基准面,即不存在陆高、海深的统一零点(图1)。

商业路线价深度修正系数表编制中平均深度百分率法的应用

商业路线价深度修正系数表的编制一直以来就存在很大的主观性和随意性,这使编制出的修正系数表与实际相差很大,在实际工作中也没有实用性.本文总结实际工作中的一点经验,提出在商业路线价深度修正系数表编制中运用平均深度百分率法,以期共同探讨.

筒体上接管插入深度计算用表

在化工容器及设备设计中,经常遇到筒体上接管长度的计算,如图1 H=h+S+h＇-K(1) 式中,h:标高,设计人员给出,mm; S:筒体壁厚mm; K:管子离法兰边缘的距离mm。 h＇是插入深度,它的计算通常采用先解三角形的方法来计算,其过程比较复杂,算出的结果也因人而异。见于这种情况,笔者对所有接管在筒体上的插入深度按式(2)都已算出,并根据制造要求加以圆整,将结果制成表1,以提高设计,校对时的速度。

黑色金属常用布氏硬度值压痕深度(h)计算表

测试布氏硬度值时的压痕深度(h)同压痕直径(d)同等重要,因为压痕深度(h)是较准确确定热处理零件加工余量的主要因素之一,但测量起来又不象压痕直径那样简单易行,通常使用计算方法来确定,而计算方法又较繁琐。因此。

幼儿建构区活动中深度学习的特征研究

区域游戏体现了以幼儿为本的教育理念,是幼儿自主学习的重要方式。建构区域游戏拥有高自主性、强交流性、真应用性的特点,这对幼儿进入深度学习有着重要作用。研究者对重庆市A幼儿园67名3—6岁幼儿在建构区的深度学习情况进行探究,采用已有的幼儿深度学习评价量表进行观察。研究结果发现,随着年龄增长,幼儿的深度学习各项能力得到普遍提升,其中联系与迁移提升幅度最大,主动性提升幅度最小;同一年龄段不同性别的幼儿在深度学习各项指标中也各有侧重,反映了一些性别特征。

无缝钢管对比试样中外表面人工缺陷尺寸的简便测量

无缝钢管对比试样中人工缺陷几何尺寸的准确与否,直接关系到探伤设备的调试是否准确,进而影响到对批量钢管质量的检验。本文详细介绍了一种测量钢管外表面人工缺陷几何尺寸的简便方法,包括具体的测量过程和测量结果的不确定度评定。该方法可进行方便的现场测量,但测量范围受限,对于内表面人工缺陷的测量还有待进一步改进。

揭秘“蛟龙号”的复杂家世

7月16日，“蛟龙号”完成了10年来的最后一次海试，凯旋青岛。 “蛟龙号”给我们展现的一面，是人类探索另一个世界的梦想与勇气。然而，当它从7000米深渊浮出水面时，它在现实世界面临的问题，恐怕比水下世界更复杂。

One-step Fabrication of Nanoporous Black Silicon Surfaces for Solar Cells using Modified Etching Solution

Currently, a conventional two-step method has been used to generate black silicon （BS） surfaces on silicon substrates for solar cell manufacturing. However, the performances of the solar cell made with such surface generation method are poor, because of the high surface recombination caused by deep etching in the conventional surface generation method for BS. In this work, a modified wet chemical etching solution with additives was developed. A homogeneous BS layer with random porous structure was obtained from the modified solution in only one step at room temperature. The BS layer had low reflectivity and shallow etching depth. The additive in the etch solution performs the function of pH-modulation. After 16-min etching, the etching depth in the samples was approximately 200 nm, and the spectrum-weighted-reflectivity in the range from 300 nm to 1200 nm was below 5%. BS solar cells were fabricated in the production line. The decreased etching depth can improve the electrical performance of solar cells because of the decrease in surface recombination. An efficiency of 15.63% for the modified etching BS solar cells was achieved on a large area, p- type single crystalline silicon substrate with a 624.32-mV open circuit voltage and a 77.88% fill factor.

Stability of long trench in soft soils by bentonite-water slurry

A series of centrifuge model tests exploring the effects of different types of slurry on long-trench stability in soft clay were conducted. The influence of groundwater conditions relative to trench stability was examined by constructing long trenches using different slurries. The soil deformation and surface settlement induced by the excavation of the trench are found to be closely related to slurry type and excavation depth of the long trench. Increasing the bentonite concentration of the slurry has beneficial effects on stability: 1) larger particles can improve local and global stability in cases where filter cakes do not form, and 2) larger viscosity can promote filter cake formation on the walls of long trenches excavated in soft clay and enhance their stability.

Modeling vertical heat transport in the wave affected surface layer of the ocean

In considering the vertical heat boundary approximation for the free surface applied. However, due to the existence of the transport problems in the upper ocean, the flat upper and the horizontal homogenous hypothesis are usually wave motion, the application of this approximation may result in some errors to the solar irradiation since it decays quickly in respect to the actual thickness of the water layer below the surface; on the other hand, due to the fluctuation of the water layer depth, it is improper to neglect the effects of the horizontal advection and turbulent diffusion since they also contribute to the vertical heat transport. A new model is constructed in this study to reflect these effects. The corresponding numerical simulations show that the wave motion may remarkably accelerate the vertical heat transferring process and the variation of the temperature in the wave affected layer appears in an oscillating manner.

Penetration depth for yaw-inducing bursting layer impacted by projectile

In order to accurately estimate the anti-penetration capacity of yaw-inducing bursting layer with irregular barriers on surface impacted by projectile,the theoretical model of attack angle and angular velocity for projectile impacting on irregular barrier was achieved according to the macroscopic relation of contact force versus contact time,in which the main factors such as the relative geometrical characteristics of projectile and irregular barrier,material property and impact velocity of projectile influencing on yaw-inducing effectiveness were considered.On the basis of considering synthetically the influences of attack angle,impact velocity,impact angle of projectile and uncontrolled free surface of target,the theoretical formulation of penetration depth for bursting layer with irregular barriers on surface impacted by projectile was presented by expressing the stress of an optional point on the nose of projectile according to the relation of stress versus velocity.The theoretical results indicate that in the case of oblique impact embodying effect of attack angle,the penetration depth is reduced with the increase of impact angle,attack angle or angular velocity,and penetration trajectory is also deflected obviously.The effectiveness of angular velocity influencing on penetration depth is increased with impact velocity increasing.The theoretical results are in good agreement with test data for low impact velocity.

城市路线基准地价测算方法研究

我国基准地价的特定含义是指城镇各级土地或域质地域及其商业、工业、住宅等土地利用类型评估土地使用权单位面积的平均价格,它反应了我国城镇土地在实际利用过程中所产生的基本经济效益,也是土地市场价格运动的基准线;客观、合理地评估地价,一是为政府依据土地经济价值制定吐地税、费提供量化标准;二是对地产市场的交易行为起指导作用。这一作用主要是就土地使用权流动而言,表现在:1、为各级政府在土地使用权有偿出让时提供定价依据;2、当土地使用权在土地使用者之间横向转让时,为转让双方提供可供参考的标准和为政府征收增殖税提供依据。

提高铸铁材料布氏硬度快速测试精度的方法

通过使用测深法快速测试铸铁材料布氏硬度的原理,分析了影响其测试精度的各种因素。通过与经验数据法及标样法的比较,确定了利用实际检验工作中的试块进行原始数据采样的方案,并对建立的压痕深度-硬度转换表进行大量的实际样块验证试验。通过对比测深法转换的硬度值以及光学压痕直径测量法计算的硬度值,分析了快速测试法的误差成因及解决方法。通过增加数据分布均匀度及在测试范围两端增加数据密度,可在保证布氏硬度测试速度及自动化程度的基础上,有效提高使用测深法测试布氏硬度的精度。

Laser ultrasonic technique for surface defects detection of 6061 aluminum alloy

In order to estimate and detect the surface defect depth of metals, the transmission method of laser ultrasonic surface waves is used in this work. The laser ultrasonic detection platform taking use of thermoelastic mechanism as acoustic signal excitation method and interference receiver as acoustic signal receiver method was built, by which B-scan images of detected specimens with surface defects were collected to establish the relationship between the transmission coefficient and depth of the surface defect. Experimental results show that the amplitude of transmitted acoustic signal is related to the depth of surface defect. At last, a fitted curve of transmission coefficient using measured experimental data is obtained to estimate depth of surface defect on the 6061 aluminum alloy. Furthermore, a surface defect depth of 0.3 mm is estimated by the fitting curve with an estimated error of 16%. Therefore, a experimental method using the transmission method by laser ultrasonic is presented in this paper.

Back analysis of general slope under earthquake forces using upper bound theorem

Long time monitoring is acquired to obtain the displacement data for displacement-based geotechnical material back analysis, and these data are hard to be measured under some special condition, such as earthquake. For a simple homogeneous slope, the position of a critical failure surface is determined by value of c/tan ~b. Utilizing upper bound theorem of limit analysis, the external work rate and internal energy for normal slope under earthquake forces are given, and the formula for minimum safety factor is derived. On this basis, the equation of slip surface and the surface depth of a given position are solved. In this way, the strength parameter can be analyzed by known slip surface depth. For practical use, the surface depth for a given slope under varying strength parameter is presented. Finally, two examples are given to show its simplicity and effectiveness.

Effect of the inclined weak interlayers on the rainfall response of a bedded rock slope

Engineering experience shows that outward dipping bedded rock slopes, especially including weak interlayers, are prone to slide under rainfall conditions. To investigate the effect of inclined weak interlayers at various levels of depth below the surface on the variation of displacements and stresses in bedded rock slopes, four geo- mechanical model tests with artificial rainfall have been conducted. Displacements, water content as well as earth pressure in the model were monitored by means of various FBG （Fiber Bragg Grating） sensors. The results showed that the amount of displacement of a slope with a weak interlayer is 2.8 to 6.2 times larger than that of a slope without a weak interlayer during one rainfall event. Furthermore, the position of the weak interlayer in terms of depth below the surface has a significant effect on the zone of deformation in the model. In the slope with a high position weak interlayer, the recorded deformation was larger in the superficial layer of the model and smaller in the frontal portion than in the slope with a low position weak interlayer. The slope with two weak interlayers has the largest deformation at all locations of all test slopes. The slope without a weak interlayer was only saturated in its superficial layer, while the displacement decreased with depth. That was different from all slopes with a weak interlayer in which the largest displacement shifted from the superficial layer to the weak interlayer when rainfall persisted. Plastic deformation of the weak interlayer promoted the formation of cracks which caused more water to flow into the slope, thus causing larger deformation in the slope with weak interlayers. In addition, the slide thrust pressure showed a vibration phenomenon o.5 to 1 hour ahead of an abrupt increase of the deformation, which was interpreted as a predictor for rainfall-induced failure of bedded rock slopes.

Time optimization for workflow scheduling based on the combination of task attributes

In order to reduce the scheduling makespan of a workflow,three list scheduling algorithms,namely,level and out-degree earliest-finish-time(LOEFT),level heterogeneous selection value(LHSV),and heterogeneous priority earliest-finish-time(HPEFT)are proposed.The main idea hidden behind these algorithms is to adopt task depth,combined with task out-degree for the accurate analysis of task prioritization and precise processor allocation to achieve time optimization.Each algorithm is divided into three stages:task levelization,task prioritization,and processor allocation.In task levelization,the workflow is divided into several independent task sets on the basis of task depth.In task prioritization,the heterogeneous priority ranking value(HPRV)of the task is calculated using task out-degree,and a non-increasing ranking queue is generated on the basis of HPRV.In processor allocation,the sorted tasks are assigned one by one to the processor to minimize makespan and complete the task-processor mapping.Simulation experiments through practical applications and stochastic workflows confirm that the three algorithms can effectively shorten the workflow makespan,and the LOEFT algorithm performs the best,and it can be concluded that task depth combined with out-degree is an effective means of reducing completion time.

Variations of SST and Thermocline Depth in the Tropical Indian Ocean During Indian Ocean Dipole Events

Interannual variations in the surface and subsurface tropical Indian Ocean were studied using HadlSST and SODA datasets. Wind and heat flux datasets were used to discuss the mechanisms for these variations. Our results indicate that the surface and subsurface variations of the tropical Indian Ocean during Indian Ocean Dipole （IOD） events are significantly different. A prominent characteristic of the eastern pole is the SSTA rebound after a cooling process, which does not take place at the subsurface layer. In the western pole, the surface anomalies last longer than the subsurface anomalies. The subsurface anomalies are strongly correlated with ENSO, while the relationship between the surface anomalies and ENSO is much weaker. And the subsurface anomalies of the two poles are negatively correlated while they are positively correlated at the surface layer. The wind and surface heat flux analysis suggests that the thermocline depth variations are mainly determined by wind stress fields, while the heat flux effect is important on SST.

路线价估价法及其在我国的应用

运用路线价估价法时,必须具备科学的城市规划、适当的路线价、合理的深度指数表以及规范的修正率等条件,应解决路线价区段的划分、路线价的确定、标准深度的设定以及有关修正率等问题。在我国,很多方面能应用这种评估方法。