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981.
运用文献资料法与资料分析法对哈尼族磨秋传统体育项目进行全面、系统、科学的介绍,并根据不同的风俗习惯、地域特征、社会生活形态等呈现出磨秋多姿多彩的局面.从发展的角度全面考察了哈尼族磨秋的历史变迁,并提出了传承保护哈尼族磨秋的一些措施:扩大宣传、通过学校体育教育推广磨秋传统体育,重视哈尼族磨秋运动的基础理论研究,建立哈尼族传统体育文化研究基地. 相似文献
982.
983.
A dragonfly wing consists of membranes and both longitudinal and cross veins. We observed the microstructure cross-section
at several locations in the dragonfly wing using environmental scanning electron microscopy (ESEM). The organic nature of
the junction between the vein and the membrane was clearly identifiable. The membrane was divided into two layers, the upper
epidermis and the lower epidermis. These layers extend around the sandwich structure vein, and combine with the adjacent membrane
at a symmetrical location along the vein. Thus, we defined this as an organic junction between the vein and the membranes.
The organic junction is able to form a tight corrugation angle, which dramatically increases both the warping rigidity and
the strength of the wing, but not the torsional rigidity. The torsional deformation is primarily controlled by the microstructure
of the longitudinal veins, and is based on the relative rotation angle between the epidermal layer and the inner layer of
the vein that forms the zigzag section. 相似文献
984.
Laurent Nottale 《Foundations of Science》2011,16(4):307-309
We give a “direction for use” of the scale relativity theory and apply it to an example of spontaneous multiscale integration
including four embedded levels of organization (intracellular, cell, tissue and organism-like levels). We conclude by an update
of our analysis of the arctic sea ice melting. 相似文献
985.
John Hamilton 《系统科学与系统工程学报(英文版)》2007,16(4):414-423
Modeling a business to match its customer perceived (and customer desired) outcomes, remains an on-going task. This paper considers shows how a service value networks (SVNs) approach may be engaged to model, and deliver, understanding of the front-end business and its direct engagement with its immediate (or front-end) customers. These front-end customers may be either: (1) its off-line, in-store customers - engaging directly with the business sales staff (or representative), or-(2) its on-line, virtual customers - engaging with the business via internet or remote access. In this situation, both the business, and the customer draw upon their respective viewpoints, and both sides influence the interaction. External to these business and customer influences are additional factors that capture the immediate and broader global effects - termed environmental effects. These three business-customer engagement areas of influence are captured by a SVN SEM approach.
Without a business-customer encounter of some kind the likelihood of a services business, and a prospecting customer, successfully engaging in an exchange process is reduced. This exchange may be a physical, and/or services exchange, and/or an information and/or ideas exchange. To the business, this encounter is, in effect, a trade, and as a result, the business targets acquiring an economic exchange that will ultimately deliver a net positive economic outcome. To the customer, external and internal information feeds, servicing, perceived value, and satisfaction, are key encounter drivers. SVNs offers a new way to understand the business-customer encounter, and to then utilize this acquired knowledge to either: (1) build a strategic management model, or (2) reengineer its business networks, and to then create a re-positioned, more customer-aligned business operation - one that is capable of delivering win - win, competitive business-customer solutions. 相似文献
Without a business-customer encounter of some kind the likelihood of a services business, and a prospecting customer, successfully engaging in an exchange process is reduced. This exchange may be a physical, and/or services exchange, and/or an information and/or ideas exchange. To the business, this encounter is, in effect, a trade, and as a result, the business targets acquiring an economic exchange that will ultimately deliver a net positive economic outcome. To the customer, external and internal information feeds, servicing, perceived value, and satisfaction, are key encounter drivers. SVNs offers a new way to understand the business-customer encounter, and to then utilize this acquired knowledge to either: (1) build a strategic management model, or (2) reengineer its business networks, and to then create a re-positioned, more customer-aligned business operation - one that is capable of delivering win - win, competitive business-customer solutions. 相似文献
986.
987.
988.
1. Introduction The Capacitated Arc Routing Problem(CARP) is defined on an undirected network inwhich a fleet of identical vehicles with limitedcapacity is based at a depot node. Each edge hasa non-negative traversal cost and can betraversed any number… 相似文献
989.
Tilman Sauer 《Archive for History of Exact Sciences》2008,62(1):1-22
Einstein’s early calculations of gravitational lensing, contained in a scratch notebook and dated to the spring of 1912, are
reexamined. A hitherto unknown letter by Einstein suggests that he entertained the idea of explaining the phenomenon of new
stars by gravitational lensing in the fall of 1915 much more seriously than was previously assumed. A reexamination of the
relevant calculations by Einstein shows that, indeed, at least some of them most likely date from early October 1915. But
in support of earlier historical interpretation of Einstein’s notes, it is argued that the appearance of Nova Geminorum 1912
(DN Gem) in March 1912 may, in fact, provide a relevant context and motivation for Einstein’s lensing calculations on the
occasion of his first meeting with Erwin Freundlich during a visit in Berlin in April 1912. We also comment on the significance
of Einstein’s consideration of gravitational lensing in the fall of 1915 for the reconstruction of Einstein’s final steps
in his path towards general relativity. 相似文献
990.