共查询到20条相似文献,搜索用时 125 毫秒
1.
南水北调视景仿真系统中动态水环境的模拟 总被引:2,自引:0,他引:2
动态水环境的模拟是南水北调视景仿真的技术难点。在分析现有动态水环境仿真模型的基础上,根据南水北调视景仿真的具体要求,利用水波动理论及计算机图形学的相关方法,实现了南水北调仿真系统视景仿真中动态水环境的仿真。实际模拟结果表明,仿真水面较为逼真,效果良好,能满足水力学仿真的需要。 相似文献
2.
疏勒河项目区盐碱地的形成及改良利用 总被引:2,自引:2,他引:2
卜秋霞 《甘肃农业大学学报》2000,35(3):301-306
疏勒河项目计划开发荒地523万hm2,由于其独特的地质、气候条件,该区土壤中普遍含盐,且中盐土和重盐土占绝大多数,主要的盐土类型有:沼泽盐土、草甸盐土、典型盐土和干旱盐土。针对不同的盐土类型,提出了相应的改良利用分区,盐土的改良,必须以“水、盐、肥”为中心,水利、农业、生物措施相结合,综合治理。 相似文献
3.
计算机通识教育是培养学生全面了解和掌握计算机科学技术的必要过程。计算机前沿技术课程的实施,能进一步促进学生在计算机领域不同方面的学习,为将来进一步深造打下良好的基础。本文探讨了利用《计算机前沿技术》课程如何实施计算机通识教育。 相似文献
4.
5.
论县级图书馆的共享工程建设 总被引:1,自引:0,他引:1
曲兆华 《农业图书情报学刊》2010,22(7):44-45,49
全国文化信息资源共享工程促进了图书馆现代化的建设。图书馆是共享工程的载体;共享工程开辟了图书馆的新天地。本文就县级图书馆在共享工程中诸多问题进行了讨论,提出了共享工程县级中心的工作策略。 相似文献
6.
7.
基于传统技术指数的经济分析会为桉树项目决策支持带来复杂性和不明确性,针对这一问题,本文提出了经济综合指数这一解决方法。通过对项目的投资、利润和时效属性的综合,创建了项目营利指数和时间指数,并将经济综合指数定义为二者的加权平均数,权重的设置由项目营利指数和时间指数间的数学关系决定。应用该经济综合指数对广西维都、玉芝树和三门江林场桉树项目进行择优,对福建省永安林业集团工业原料林项目的经营方案进行设计,以及对三门江林场桉树项目进行敏感性分析时所得到的3组结果,与事实和已有研究结论吻合,且过程简捷,计算高效,结论明确。因此,经济综合指数是当前森林经营项目经济效益分析方法的补充。 相似文献
8.
典型区域退耕还林工程生态区划 总被引:2,自引:0,他引:2
9.
计算机专业英语教学模式的探讨 总被引:2,自引:0,他引:2
丁海燕 《云南农业大学学报(自然科学版)》2008,(6)
计算机专业英语是以学习专业词汇表达和培养英语应用能力为目的的一门专业选修课,不完全等同于双语课程。在教学实践的基础上,分析计算机专业英语教学普遍存在的现状,由于兼有专业课与英语课的双重特点,因此计算机专业英语在课程内容、教学资源及教学活动的组织上都有其特殊性。探讨专业英语的几种教学模式,提出计算机专业英语课程教学改革的思路。 相似文献
10.
大通县退耕还林工程成效及存在问题 总被引:3,自引:0,他引:3
2000-2008年,大通县共完成退耕还林工程造林面积15193.34hm2,工程的实施在推进大通县生态环境建设、促进农业产业结构调整,增加农民的收入等方面取得了显著成效,但也存在一些问题,本文就退耕还林工程成效、存在问题进行了调研并提出了应对措施。 相似文献
11.
12.
Computer-assisted analysis of chromosomal abnormalities: detection of a deletion in aniridia-Wilms' tumor syndrome 总被引:2,自引:0,他引:2
R Ladda L Atkins J Littlefield P Neurath K M Marimuthu 《Science (New York, N.Y.)》1974,185(153):784-787
A chromosome translocation, t(8p + ; 11q -), in a patient with aniridia and Wilms' tumor, appeared balanced by standard techniques, including trypsin banding. Computer analysis of optical microscope scanning profiles of chromosome pairs 8 and 11 revealed an interstitial deletion of the short arm of 8. Computer analysis coupled to the new banding techniques provides greater resolution for the detection of subtle chromosomal variations not recognized by banding methods alone. 相似文献
13.
中俄东线天然气管道工程是“一带一路”倡议下中俄两国深化合作的成功典范,作为跨境输气管道的代表性项目,前期工作特征与经验具有重要的参考借鉴价值。阐述了中俄东线天然气管道工程项目的背景与意义,梳理了其商业谈判、预可行性研究、可行性研究、项目申请报告编制及核准等前期工作,介绍了针对中俄东线天然气管道工程复杂技术经济工况的专题研究过程,总结了中俄东线天然气管道工程前期工作的创新成果。研究表明:中俄东线天然气管道工程这类大型跨境能源管道项目,其前期工作涉及外交、商业、技术、经济等多层次问题,需要投入更多的人力、研究资源及更充裕的时间,以保障项目的顺利实施。 相似文献
14.
以《计算机研究与发展》2001~2005年60期共1407篇论文为统计源,对《计算机研究与发展》载文的第一作者情况进行统计,并从发文作者的年龄、学历、职称,地区分布,系统分布,合著情况等角度进行分析.以揭示我国计算机领域研究队伍的现状,为计算机学科研究提供某一角度的参考。 相似文献
15.
16.
17.
Since 2010, demand for non-GMO food products has grown dramatically. Two non-GMO labels dominate the market: USDA Organic and the Non-GMO Project Verified (the Project). However, the non-GMO status of Organic is not obvious from the label and many consumers are unaware of this. As sales of products carrying the Project’s non-GMO label have exploded, concern has increased among some Organic proponents that demand for non-GMO threatens the organic market. In response, both sides are seeking to build legitimacy and authority for their label by emphasizing the value of their standards for determining a food product’s non-GMO status within a GMO contaminated agrifood system. Drawing on in-depth interviews with key informants with knowledge of non-GMO standards and labels, we examine the knowledge systems, discourses and actors that proponents of the Project and USDA Organic privilege in their effort to legitimize their standards. Here, the Project emphasizes its application of technoscientific norms, especially thresholds and testing, which they argue provide the best means for preventing GMO contamination and helping consumers find (relative) non-GMO ‘purity’. In contrast, proponents of Organic favor a process standard that excludes GMOs, arguing that non-GMO ‘purity’ is unrealistic in today’s agrifood system that is widely contaminated by GMOs and where mandatory testing would unnecessarily harm organic producers. We conclude that tensions between the two groups are unlikely to be easily reconciled since these two distinct marketing labels rely on different knowledge and verification claims to vie for consumers and increase market share. 相似文献
18.
农地整理工程改变了整理区的土地利用类型,使其原生态系统的能量流、物质流和信息流发生改变,进而导致生态系统服务价值发生变化。依据不同的地貌类型,在湖北省境内选取3个典型项目作为研究对象,测算了农地整理前后项目区的生态系统服务价值。研究结果表明:新增耕地数量最多的是"竹山项目"、净增348.84 hm2,居中的是"当阳项目"、净增62.32 hm2,最少的是"钟祥项目"、净增44.27 hm2。3个农地整理项目区的生态系统服务价值都发生损失,"竹山项目"净减271.0×104元/年,"当阳项目"净减51.0×104元/年,"钟祥项目"净减8.0×104元/年。不同地貌类型项目区的单项生态系统服务价值损失存在较大差异,"竹山项目"的气体调节价值损失最大,"当阳项目"的气体调节价值损失最小;"竹山项目"的食物生产价值增加11.0×104元/年,"钟祥项目"增加1.0×104元/年。研究得到的政策启示:农地整理目标必须从新增耕地数量向更加注重耕地质量和生态环境转变,紧紧围绕和考虑生产、生活和生态,实施数量、质量、生态三位一体的整理模式。 相似文献
19.
针对西气东输天然气管道工程钢管进口的实际情况,应用数理统计的方法,对进口钢管的相关数值指标进行了统计,进而确定了使抽样检验结果具有一定可信度的采样数值范围,并根据进口钢管的清单确定了取样样本数量。 相似文献
20.
Karen L. Webb David Pelletier Audrey N. Maretzki Jennifer Wilkins 《Agriculture and Human Values》1998,15(1):65-75
Several different evaluation issuesare perceived as important by people involved withinnovative projects intended to improve local food andnutrition systems; particularly the establishment oflocal food policy coalitions. Several such coalitionshave been formed in North America, Europe, andAustralia with the goal of improving community foodsecurity and promoting sustainable local food systems.Pioneer coalitions have served as models, yet therehas been little systematic evaluation of thesemodels. A qualitative study was conducted to identifyfactors that may hinder evaluation efforts. In grouptelephone interviews, we sought the views ofacademics, project organizers, and funders, a total of24 key informants. Pressures to evaluate were assessed differently bythe three groups of key informants. Academics felt thefocus of evaluation should be on the effectiveness ofthe process used to discuss issues and formulatepolicies and plans. Project organizers and fundersperceived a need to assess project impact andoutcomes. A lack of suitable evaluation models andmethods was viewed as a formidable barrier. The use ofinappropriate methods and premature impact evaluationwere noted as potential threats to projectsustainability. External constraints and resourcelimitations were also said to inhibit evaluationefforts. It appears that several other factors may also beimpeding progress in conducting more (and more useful)evaluations including: (1) the apparent negativeconnotation of evaluation and the limited benefitsexpected from evaluation by stakeholders, (2) a lackof consensus about important evaluation questions,(3) insufficient evaluation expertise among projectorganizers, and (4) inadequate appreciation ofincreasing accountability pressures. 相似文献