基于分布式对象技术的NC2000水电厂计算机监控系统软件

介绍了为适应水电厂生产管理水平不断提高的新要求而研制的计算机监控系统软件NC2000。简要地介绍了面向对象技术，分布式对象技术、3层次Client/Server结构等NC2000系统中所采用的新技术以及NC2000的一些主要特点。     

浅埋式滴灌条件下毛管间距对苜蓿生长的影响

为了探讨浅埋式滴灌毛管间距对苜蓿生长的影响,在阿勒泰市青河地区进行苜蓿浅埋式滴灌田间试验,试验设置30、60、90 cm 3种毛管间距。通过观测各土层含水率、苜蓿毛细根密度以及生长指标等,研究毛管间距对土壤水分以及苜蓿生长的影响。结果表明:毛管间距为60、90 cm处理的各土层含水率增值优于30cm处理;毛管间距30、60 cm处理苜蓿的毛细根密度明显高于毛管间距90 cm的处理;毛管间距为30、60 cm的处理对苜蓿生长的影响差异较小,其中以间距60 cm处理为优,而间距为90 cm对其影响较大,不利于苜蓿的生长。因此,毛管间距以60 cm最优,适合该地区苜蓿的灌溉。     

关山特长隧道高地应力下硬岩大变形规律研究

高地应力下隧道的围岩变形是岩体力学的关键问题之一,甘肃关山隧道埋深较大,在穿越高地应力区域时极易出现围岩失稳、塌方及支护结构大变形等现象。选取隧道典型试验段,通过数值计算及数据监测,对其大变形规律和防控技术进行了研究,进而得到了隧道围岩的变形和应力分布规律。根据分析结果,建议隧道衬砌施工时采用柔性支护的理念进行设计,优化边墙曲率,加大预留变形量,采取径向注浆加固及降低扰动。实践表明,一系列防控措施有效控制了围岩变形,降低了隧道施工风险,可为以后类似工程的设计和施工提供实践借鉴。     

The Mahomet Aquifer

Abstract

Emerging intrastate transboundary issues focus on use of the Mahomet aquifer, which underlies about fifteen counties and many other political entities in east-central Illinois. This sand and gravel aquifer in the lower part of the buried Mahomet Bedrock Valley ranges between four and fourteen miles wide and from about 50 to 200 feet thick. Much of the region's rural population, several large communities, and many small towns obtain water from the Mahomet aquifer, as do industrial, agricultural, and commercial users. Increased development of the Mahomet aquifer to meet growing demands for water has caused conflicts over real or perceived adverse effects. One result has been the creation of fifteen resource protection zones and twelve water authorities. For groundwater supplies, resource protection zones help municipalities protect water-supply wells from potential adverse impacts. Many resource protection zones overlap one another, however, so this situation could lead to disputes over use of the resource. The reason that several of the twelve water authorities were organized was to meet a challenge perceived from a demand to be placed on the aquifer, in other words, a potential for conflict of use. Complicating the situation is that some of the water authorities overlap the resource protection zones. This could lead to disputes not only about water use, but also over which jurisdiction has the authority to settle a dispute. The Mahomet Aquifer Consortium was recently organized by concerned people representing diverse groundwater interests at the local level, including the private sector, professional organizations, and various governmental units. The consortium brings together representatives of some groups that typically did not communicate with each other in the past. The consortium may provide a forum through which emerging transboundary issues pertaining to use of the Mahomet aquifer can be addressed. Because the consortium is a voluntary organization that relies on consensus building, the success it may achieve in resolving future conflicts over groundwater use from the Mahomet aquifer remains to be seen.     

特大型洞室过浅埋段的开挖与支护

泸定水电站2号泄洪洞为特大断面洞室,具有开挖断面大、跨度宽、地质条件复杂等特点,特别是浑水沟段垂直埋深小(最小岩层埋深为6 m).根据地质勘探资料及现场地表勘查情况,通过对该段采用地表处理与洞室内处理相结合的手段,顺利完成了该洞室的开挖、支护,确保了洞室按期过流,为工程顺利进行奠定了良好的基础.     

利民堡深埋红粘土隧洞的新奥法施工

粘土地层特别是在地下水位以下进行隧洞开挖时，随着洞周应力的释放将产生较大的收敛变形，极易导致围岩失稳并造成塌方，对于在埋深较大的塑性粘土地层中开挖隧洞，其施工难度就更大。作为一个典型工程实例，引黄南干５＾＃洞利民堡洞段粘土覆盖层厚度深达１８０ｍ，围岩应力高达３．６ＭＰａ，但由于合理运用了新奥法施工，包括采用分步开挖断面、适当预留收敛变形量、缩短开挖循环进尺、加密格栅拱架和及时喷混凝土支护等综合措施，因而顺利贯通。     

地下水埋深对冻融土壤水分入渗特性影响的试验研究

本文基于冻融期间大田测坑不同地下水埋深条件下，自然冻结土壤水分入渗试验，分析讨论了地下水埋深对冻融土壤水分入渗能力、相对稳渗率的影响和冻融期间土壤入渗能力的变化特点。结果表明：地下水埋深对冻融土壤入渗能力的影响十分明显；土壤入渗能力随地下水埋深的增大而增大；冻融土壤的相对稳渗率随地下水埋深的减小而减小；冻融期间地下水埋深小的土壤的入渗能力始终小于地下水埋深大的土壤的入渗能力。地下水埋深对冻融土壤水分入渗能力的影响通过其对地表土壤含水量的影响而实现。研究结果对于指导季节性冻土地区冬、春灌溉合理灌水技术参数的确定具有实际意义     

近30年来白洋淀流域平原区地下水位动态变化及原因分析

白洋淀流域平原区是华北平原的农业高产区域,灌溉用水主要靠开采地下水。近几十年来,白洋淀地下水位下降严重,在1974年-2007年。该区域地下水埋深以平均每年0．51m的速率下降,1980年以后下降速率明显加速,在2000年-2007年年均下降速率达到了0．99m。引起地下水位持续下降的主要原因是地下水超采严重,且用水高峰期遭遇枯水期,尤其体现在1980年以后年降水偏枯．同时社会经济用水量维持在高峰阶段。低效的农业用水模式及地下水超采已经严重制约了白洋淀地区水资源的可持续利用。     

济南市区段暗涵冬期施工技术研究与实践

济南市区段输水暗涵济洛路至洪家园桥段跨冬季施工,结合工程特点采用暖棚法施工,采取经济有效的暖棚支架和外敷保温材料。根据可施工工作面及热源条件,加热方式采取蒸汽锅炉通过管道向暖棚内供热。同时采取混凝土强度试件与洞身同条件养护,以检验拆模及拆暖棚的时机。为控制混凝土内外温差,同时保证混凝土达到设计强度85％前不受负温,暖棚拆除后对裸露混凝土表面继续保温养护。     

Grasp and Delivery for Moving Objects on Broken Lines

This paper studies the following variant of the Vehicle Routing Problem that we call the Grasp and Delivery for Moving Objects (GDMO) problem, motivated by robot navigation: The input to the problem consists of n products, each of which moves on a predefined path with a fixed constant speed, and a robot arm of capacity one. In each round, the robot arm grasps one product and then delivers it to the depot. The goal of the problem is to find a collection of tours such that the robot arm grasps and delivers as many products as possible. In this paper we prove the following results: (i) If the products move on broken lines with at least one bend, then the GDMO is MAXSNP-hard, and (ii) it can be approximated with ratio 2. However, (iii) if we impose the “straight line without bend” restriction on the motion of every product, then the GDMO becomes tractable. Y. Asahiro’s research was supported in part by Grant-in-Aid for Young Scientists 15700021, and Research on Priority Areas 16092223. E. Miyano’s research was supported in part by Grant-in-Aid for Research on Priority Areas 16092223. Presently, S. Shimoirisa is with the Software Development Engineering Department, Products Development Center, Retail Information Systems Company, Toshiba TEC Corporation.