全文获取类型
收费全文 | 107篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 21篇 |
金属工艺 | 1篇 |
机械仪表 | 4篇 |
建筑科学 | 2篇 |
能源动力 | 11篇 |
轻工业 | 9篇 |
水利工程 | 2篇 |
无线电 | 10篇 |
一般工业技术 | 33篇 |
冶金工业 | 10篇 |
自动化技术 | 9篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 12篇 |
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 7篇 |
2012年 | 2篇 |
2011年 | 6篇 |
2010年 | 7篇 |
2009年 | 1篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 1篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
2.
Text-based image retrieval may perform poorly due to the irrelevant and/or incomplete text surrounding the images in the web pages. In such situations, visual content of the images can be leveraged to improve the image ranking performance. In this paper, we look into this problem of image re-ranking and propose a system that automatically constructs multiple candidate “multi-instance bags (MI-bags)”, which are likely to contain relevant images. These automatically constructed bags are then utilized by ensembles of Multiple Instance Learning (MIL) classifiers and the images are re-ranked according to the final classification responses. Our method is unsupervised in the sense that, the only input to the system is the text query itself, without any user feedback or annotation. The experimental results demonstrate that constructing multiple instance bags based on the retrieval order and utilizing ensembles of MIL classifiers greatly enhance the retrieval performance, achieving on par or better results compared to the state-of-the-art. 相似文献
3.
Pavements constructed for the purpose of meeting the demand of highways which were emerged with the improving technological developments increased. And consequently, more resources were demanded to be directed to pavement maintenance and rehabilitation. Hereby, the concept of pavement management emerged. Although project-level analyses were found adequate previously, network-level evaluations were needed in order to do detailed planning as a result of resource allocation and transfer problems that were emerged later. Therefore, pavement management system has become compulsory for all pavements to be controlled together. In this framework, programming is needed in order to schedule maintenance–rehabilitation and develop costs with respect to budget. In the study carried out, a mode was developed in order to program the routine network maintenance activities in terms of Pavement Maintenance and Management Systems, and it was concluded that this problem can be solved through ant colony, using Visual Basic. 相似文献
4.
5.
This study addresses heat and mass transfer during the vaporization of a liquid in a heated square cross-section mini-channel. A theoretical model is developed in steady state using the radius of curvature as a variable. One-dimensional simulations have been performed. An analysis of this model reveals that heat and mass transfer is governed by two main groups of non-dimensional numbers (i.e., Reynolds × Boiling and Weber × Boiling2 numbers). Maps of heat transfer performance are thus proposed according to these non-dimensional numbers. A reduced model is finally derived, allowing the main parameters to be expressed (such as the extended meniscus length) analytically. 相似文献
6.
7.
An environmental and technical sustainability assessment methodology is developed for both centralized and dual water distribution systems (WDSs) with and without fire flow scenarios. Technical sustainability of potable and reclaimed water networks is measured by a sustainability index (SI) assessment using reliability, resiliency, and vulnerability performance criteria. The U.S. Environmental Protection Agency EPANET software is used to simulate hydraulic (i.e. nodal pressure) and water quality (i.e. water age) analysis in a WDS. Total fresh water use and total energy intensity are considered as environmental sustainability criteria. The procedure considers two separate alternatives for meeting fire flows: (1) adding pumping to a system or (2) adding a non-potable WDS. The reclaimed system is designed using linear programming (LP) optimization. For each alternative, multi-criteria decision analysis (MCDA) is used to combine technical and environmental sustainability criteria for an urban WDS. 相似文献
8.
I. Dumanoglu N. Akchurin U. Akgun S. Ayan P. Bruecken E. Eskut A. Fenyvesi A. Kayis Topkasu N. Koca K. Makonyi J. -P. Merlo D. Novak Y. Onel G. Onengut A. Polatoz I. Schmidt M. Serin M. Zeyrek 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2002,490(3):444-455
We investigated the darkening of nine high OH− fibre types irradiated with 500 MeV electrons from the Linac Injector of LEP (LIL) at CERN. The transmission of Xe light was measured in situ in the 350–800 nm range. The induced attenuation at 450 nm is typically 1.52±0.15 dB/m for a 100 Mrad absorbed dose. Two-parameter fits for darkening and recovery are presented. After irradiation the tensile strength remains essentially unchanged. For Polymicro quartz core fibres the tensile strength is typically 4.6±0.4 GPa. 相似文献
9.
M Ba?bu? E Aygen M Tayyar E Kaya I Demir S Serin 《Canadian Metallurgical Quarterly》1997,42(9):600-602
BACKGROUND: Although hydatidiform mole is not commonly encountered following ovulation induction, patients who have already had molar pregnancies are at increased risk of developing further molar diseases with worsening histologic characteristics. That fact underlies the ethical dilemma of repeat ovulation induction. CASE: A 38-year-old woman, gravida 3, para 0, had three consecutive episodes of hydatidiform subsequent to clomiphene citrate and gonadotropin ovulation induction. She seems to be the first in the literature to develop three consecutive molar pregnancies without a normal intrauterine pregnancy. CONCLUSION: Although ovulation induction commenced again in this patient after she gave informed consent, the risks underlying the ethical dilemma persist. 相似文献
10.
Lymphoedema of the upper limb after breast cancer treated with axillary clearance is a well known sequels. But its real rate is not precise. The retrospective study of 683 patients approaches this reality. When clinic criteria are selected with centimetric measures, its general rate is 41%; 65% out of them have a difference smaller than 3 cm. We noticed three different kinds of lymphoedemas which occur on the arm, the forearm or the complete upper limb. Their volumes are different, the more voluminous ones occur when the upper limb is touched completely (P = 0.0001). The different factors which increase the risk of lymphoedema are described. The role of the infection is noticed (x 1.7). The rate is independent of the surgery, of the importance of axillary clearance and of the shoulder joint function. The lymphoedema size is more important when it occurs secondary to mastectomy then conservative treatment (P = 0.0078). Parietal fibrosis increases lymphoedema risk to 54% (P = 0.005) and lymphoedemas are more voluminous (P = 0.009). 相似文献