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101.
通过人工肉眼对地质雷达探测图像进行判读的方法易受判读人员主观性、经验性影响。为了规避这一不足,提出一种基于Counterlet等高变换和K-Means++均值聚类分析的频谱能量判读方法。以实际公路隧道为依托,经现场探测获取不良地质体的原始探测数据;采用IDSP探测数据分析软件生成原始图像及实施背景去除、滤波等时域、频域预处理以提高信噪比;基于子带分布系数采用Counterlet对预处理后的图像进行分解和重构,并采用K-Means++算法将重构后图像中的频率信息转化为颜色特征;利用MATLAB对颜色特征进行提取并据此建立不良地质体颜色特征样本库,将原始探测图像与样本库进行匹配对比以实现自动判读。结果表明:采用Counterlet等高变换对多方向、多分辨率、多尺度的地质雷达图像进行分解与重构是可行的,曲线边缘逼近效果良好,重构后的图像无信息丢失;K-Means++算法能实现地质雷达灰度图像中能量~频率~色彩的转化,转化后的图像色彩突出、直观;频谱能量的匹配对比能较准确、快速地实现自动判读及较好地规避个体主观性。 相似文献
102.
分析和论述了马迹塘地区的地层、岩石及地质构造在卫星照片和航空照片上的影象特征及其遥感地质解译。对该地区乃至湘中部地区的区域地质调查、普查找矿、地质灾害监测有一定的指导与借鉴作用。 相似文献
103.
本文利用Aster遥感数字图像,建立了彬县煤矸石电厂评价区各土地利用现状类型的遥感影像特征,采用目视解译和人机交互解译相结合的方法,圈定了土地利用现状类型范围,在此基础上,进行土地利用类型面积统计,总结各土地利用现状的空间分布特征,为了科学地评价电厂建设对生态环境的影响提供了基础依据。 相似文献
104.
鉴于历史地图自身信息的模糊性,采用历史地图解译法对桂湖水系相关的历史地图进行解译绘制,通过解译图纸能较为清楚展示桂湖水系的演变过程,进而相对客观地总结其水系的演变特点。从城市水系与园林水源、水系周边建筑营建、水系空间形态划分3个方面,按照隋唐、宋代、明清、近代、现代的时间段对桂湖水系的演变过程进行梳理,并从新都城市水系与桂湖园林水系的关系、水系周边建筑功能及附属空间属性的变化、水系形态的艺术划分3方面归纳总结水系演变特点: 1)新都城市水系与桂湖园林水系在形态结构联系上呈现出完整、完善、破坏、重建4个阶段,桂湖园林水系与新都城市水系在水系体系构成上经历融合、维持、撤离、融入4个阶段的变化。2)水系周边建筑功能经纪念性萌芽、公共性增强、纪念性强化、纪念性精炼的变化,其建筑附属空间布局经历游赏性空间错列分布、公共性空间沿岸排布、纪念性空间中心贯穿、纪念性空间核心主导的4个阶段,使得桂湖从以游玩聚会为主的驿站园林变为以纪念为主的公共园林。3)桂湖水系的形态结构划分呈一池三岛“粗”分、五岛两堤“概”分、五岛两堤“密”分与五岛两堤“旷”分的演变特点。 相似文献
105.
106.
Beatrix Haselsberger 《Planning Theory & Practice》2013,14(4):505-526
In our globalised, interconnected world the impact of borders on space and people is increasingly debated. This article aims to unpack the complex concept of “thick” and “thin” borders. It builds on the assumption that borders are boundary sets comprised of overlapping geopolitical, sociocultural, economic and biophysical layers and are the outcome of a bordering process. A two-step approach towards the decoding of borders is introduced. Using a planning perspective, the article seeks to explain the various functions of borders, to examine power practices within the bordering process and to ascertain the relational geographies demarcated by different types of boundaries. It illustrates why those cross-border activities which address only the geopolitical dimension of the border tend to fail. 相似文献
107.
Brent D. Ryan 《Journal of the American Planning Association. American Planning Association》2013,79(4):309-327
Problem: Planners may read plans often, but the profession continues to view the interpretation of plan content as something that is either too obvious or too unimportant to require explicit discussion. Plans are seldom adequately interpreted. This is regrettable because plans contain a rich variety of content and meaning. Purpose: This article calls for planners to “read through” plans, not just to grasp their essential ideas or the means of implementing those ideas, but also to perceive additional levels of meaning relating to a) a plan's place within a larger intellectual sphere, b) a plan's statement on the social and political values of the time, and c) a plan as a part of the history of the planning profession and the life of cities. Methods: I propose a visual approach to plan reading descended from Panofsky's (1939) theory of iconology and use this to examine three very different plans that describe different size cities (small, large, very large) during different periods over the past 80 years (the 1930s, 1960s, 2000s). I analyze three levels of meaning in each plan: its factual meaning, or “plain sense” (Mandelbaum, 1990); its contextual meaning, or relation to political, social, economic, and physical conditions; and its temporal meaning, or setting within the scope of observations made by other plan readers in the perspective of elapsed time. Results and conclusions: Factual readings show that information may be found in diverse aspects of a plan document, from seemingly superficial aspects like its cover to unarguably central elements such as recommendations. Factual readings depend on understanding the relationships among different elements, and reveal information about the plan and its framers that may not otherwise be readily apparent. Contextual readings show us that plan recommendations are as much a product of contemporary conditions and norms as they are of plan-specific “survey and diagnosis” (Nolen, 1936). This raises the question of whether plan quality is to be judged only in terms of skillful execution of concerns of the day or whether innovation is also important. Temporal readings reveal that plans and planning have changed dramatically over time, simultaneously confirming and questioning the conventional wisdom of planning history. Takeaway for practice: Many planners read plans on a regular basis, and plans continue to constitute the major printed currency of the planning profession. Both plans and planning will benefit if planners become more discerning readers of the profession's principal idea vessels. Formal plan interpretation is rare, but each planner can become a better plan interpreter. Research support: None. 相似文献
108.
《Material Religion》2013,9(2):142-155
ABSTRACTIntroducing the themes and contexts for this special issue of the journal, this editorial reflects particularly on the experience of museums and museum and heritage educators in the UK and Asia in interpreting religions and religious art. It looks at successful examples of specialist museum programs and exhibits on religions; and distance learning resources that include faiths in suggesting new approaches to citizenship education through cultural learning. It looks more broadly at new approaches to religious education that encompass sacred spaces. 相似文献
109.
110.
《Soils and Foundations》2014,54(6):1104-1116
An alternative approach is developed in order to estimate the hydraulic conductivity of soft fine grained soils, based on numerical simulation of the full penetration and dissipation process for piezocones. Unlike previous methods of analysis, the process of penetration and dissipation has been explicitly simulated, thus eliminating several of the simplifications inherent in existing interpretation methods such as geometric approximations, predefined stress fields or neglecting material compressibility. The presented method is not established upon a particular set of data leading to limited applicability, but is rather developed using a more general approach and can be extended to other datasets if intended. Given the time to 50% consolidation and a number of influencing soil parameters, a single estimate of the soil horizontal permeability can be obtained via a single-run piezocone sounding using pore pressure measurements taken at the shoulder filter element (u2) located immediately behind the cone.The proposed interpretation method embodies many of the key parameters (namely the soil shear strength, soil rigidity, and soil confining stresses) likely to influence the soil behaviour and thus the parameter to be interpreted. Numerical analyses demonstrated that the rate of dissipation increases as the soil rigidity or the soil confining pressure increases, which is a consequence of higher excess pore pressure gradient at higher depths or at larger rigidities. The method, which involves a new excess pore pressure normalisation technique, is applicable to both monotonic and dilative dissipation data. The proposed interpretation method is compared to a series of experimental data including two recent field tests. Although the method was calibrated against only a select few cases, its applicability to a wide range of clayey soils was verified. 相似文献