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11.
陶忠良 《吉林化工学院学报》2020,37(2):54-57
地方高校发展建设不断面对新的机遇和挑战,能否科学的制定并实施发展规划,对高校的发展具有重要的战略意义。规划编制要对内容与方法不断探索研究,是总结上一规划制定及执行情况,对学校内外发展形势准确剖析,是明确学校今后一段时间的建设任务和建设发展目标的理性探究。 相似文献
12.
Siim Sultson 《Planning Perspectives》2018,33(3):385-409
Estonian 1940s–1950s town planning practices show that Stalinist principles were in line with those of Estonian architects during the 1930s pre-war, independence period. However, between 1944 and 1955, within the context of the Soviet regime’s occupation, urban planning was faced with rigid ideological constraints. After the Second World War, Estonian architects were forced to abandon projects in historical city centres, which focused on maintaining local natural conditions and cultural heritage, as well as using local materials. Some existing town centres, such as in Tallinn, Narva, and Pärnu, were reconstructed after suffering damage in the war, as well as for ideological reasons. Yet, during this time period, most efforts were directed towards building new industrial towns in East Estonia that exemplified a Stalinist utopia; this also presented the Soviet regime with an opportunity to exploit local mineral resources. 相似文献
13.
Piotr Gas Arkadiusz Miaskowski Mahendran Subramanian 《International journal of molecular sciences》2020,21(22)
Electromagnetic hyperthermia as a potent adjuvant for conventional cancer therapies can be considered valuable in modern oncology, as its task is to thermally destroy cancer cells exposed to high-frequency electromagnetic fields. Hyperthermia treatment planning based on computer in silico simulations has the potential to improve the localized heating of breast tissues through the use of the phased-array dipole applicators. Herein, we intended to improve our understanding of temperature estimation in an anatomically accurate female breast phantom embedded with a tumor, particularly when it is exposed to an eight-element dipole antenna matrix surrounding the breast tissues. The Maxwell equations coupled with the modified Pennes’ bioheat equation was solved in the modelled breast tissues using the finite-difference time-domain (FDTD) engine. The microwave (MW) applicators around the object were modelled with shortened half-wavelength dipole antennas operating at the same 1 GHz frequency, but with different input power and phases for the dipole sources. The total input power of an eight-dipole antenna matrix was set at 8 W so that the temperature in the breast tumor did not exceed 42 °C. Finding the optimal setting for each dipole antenna from the matrix was our primary objective. Such a procedure should form the basis of any successful hyperthermia treatment planning. We applied the algorithm of multi for multi-objective optimization for the power and phases for the dipole sources in terms of maximizing the specific absorption rate (SAR) parameter inside the breast tumor while minimizing this parameter in the healthy tissues. Electro-thermal simulations were performed for tumors of different radii to confirm the reliable operation of the given optimization procedure. In the next step, thermal profiles for tumors of various sizes were calculated for the optimal parameters of dipole sources. The computed results showed that larger tumors heated better than smaller tumors; however, the procedure worked well regardless of the tumor size. This verifies the effectiveness of the applied optimization method, regardless of the various stages of breast tumor development. 相似文献
14.
自动铺带技术是一种增量制造技术,适用于制造翼面、壁板等大尺寸、小曲率复合材料构件,具有加工成本低、效率高等特点。轨迹规划是自动铺带技术的关键环节,它直接关系到复合材料构件的成型精度与质量。现有的自动铺带轨迹规划方法难以便捷兼顾调控铺放间隙与防止铺放褶皱,保证铺带产品的最终质量。有鉴于此,提出了一种基于近似测地线的分层次铺放轨迹规划方法。主要目标是合理利用预浸带允许变形能力,在防止铺放褶皱产生的前提下,保证相邻带料不产生覆盖,且间隙不超过2.5 mm。首先,研究了铺放间隙的产生与演化规律,给出了几种典型曲面上初始铺放间隙的优化方法。接下来,提出了近似测地线的数学模型与求解格式。然后,基于铺放褶皱的产生机制与铺放间隙的演化规律,确定了近似测地线的测地曲率大小与符号。最后,在双曲面模具以及自由曲面模具上验证了所提出方法的有效性。 相似文献
15.
16.
The ‘actually existing’ smart city is not a monolith. It is not directed by a universal logic, nor does it develop in a standardised way. As recent research has argued, the spatial, material, and political contexts of cities have major influence over what smart urbanism looks like in practice. This paper adds analytical depth to, and broadens the geographical scope of, research on the variegated modes of making smart cities. Based on empirical research in multiple Australian cities we use three case studies to explore three different modes of smart urbanism, each one centred on the interests of a different key actor: corporate-centric, citizen-centric, and planner-centric. These different modes can, and do, co-exist in the same city. At times, they are competing logics that fight to pull the city in different directions. Yet, they can also work together to shape smart city initiatives. In describing these different modes, we pay particular attention to the ways that these projects and strategies must contend with the already existing spatial, cultural, and political contexts of each place. 相似文献
17.
设施园艺可以让农业生产者通过一定的技术手段,提高农业生产效益,改变农作物的生长周期。文章在农业观光园的设计中可以利用这种技术方法来突出园区的农业特色,吸引非农业人口前来旅游观光和消费。 相似文献
18.
Lack of constraint-free crane path planning is one of the critical concerns in the dynamic on-site assembly process of prefabrication housing production (PHP). For decades, researchers and practitioners have endeavored to improve both the efficiency and safety of crane path planning from either static environment or re-planning the path when colliding with constraints or periodically updating the path in the dynamic environment. However, there is a lack of approach related to the in-depth exploration of the nature of dynamic constraints so as to assist the crane operators in making adaptive path re-planning decisions by categorizing and prioritizing constraints. To address this issue, this study develops the smart work packaging (SWP)-enabled constraints optimization service. This service embraces the core characteristics of SWP, including adaptivity, sociability, and autonomy to achieve autonomous initial path planning, networked constraints classification, and adaptive decisions on path re-planning. This service is simulated and verified in the BIM environment, and it is found that SWP-enabled constraints optimization service can generate the constraint-free path when it is necessary. 相似文献
19.
Highly accurate real‐time localization is of fundamental importance for the safety and efficiency of planetary rovers exploring the surface of Mars. Mars rover operations rely on vision‐based systems to avoid hazards as well as plan safe routes. However, vision‐based systems operate on the assumption that sufficient visual texture is visible in the scene. This poses a challenge for vision‐based navigation on Mars where regions lacking visual texture are prevalent. To overcome this, we make use of the ability of the rover to actively steer the visual sensor to improve fault tolerance and maximize the perception performance. This paper answers the question of where and when to look by presenting a method for predicting the sensor trajectory that maximizes the localization performance of the rover. This is accomplished by an online assessment of possible trajectories using synthetic, future camera views created from previous observations of the scene. The proposed trajectories are quantified and chosen based on the expected localization performance. In this study, we validate the proposed method in field experiments at the Jet Propulsion Laboratory (JPL) Mars Yard. Furthermore, multiple performance metrics are identified and evaluated for reducing the overall runtime of the algorithm. We show how actively steering the perception system increases the localization accuracy compared with traditional fixed‐sensor configurations. 相似文献
20.
分析近代天津历次近代城市规划中机场布局思想的演进历程,采用比较研究方法剖析天津近代各类机场设计方案的异同及其各自特征,并总结了天津近代机场场面规制及其跑道形制在不同时期的演进规律,还从规划编制体例角度论证了天津近代机场规划及其实例应用。 相似文献