全文获取类型
收费全文 | 2167篇 |
免费 | 110篇 |
国内免费 | 123篇 |
专业分类
电工技术 | 39篇 |
综合类 | 84篇 |
化学工业 | 38篇 |
金属工艺 | 16篇 |
机械仪表 | 96篇 |
建筑科学 | 113篇 |
矿业工程 | 11篇 |
能源动力 | 11篇 |
轻工业 | 35篇 |
水利工程 | 21篇 |
石油天然气 | 7篇 |
武器工业 | 10篇 |
无线电 | 151篇 |
一般工业技术 | 113篇 |
冶金工业 | 35篇 |
原子能技术 | 7篇 |
自动化技术 | 1613篇 |
出版年
2024年 | 10篇 |
2023年 | 20篇 |
2022年 | 36篇 |
2021年 | 32篇 |
2020年 | 36篇 |
2019年 | 20篇 |
2018年 | 33篇 |
2017年 | 45篇 |
2016年 | 63篇 |
2015年 | 67篇 |
2014年 | 117篇 |
2013年 | 108篇 |
2012年 | 165篇 |
2011年 | 131篇 |
2010年 | 101篇 |
2009年 | 142篇 |
2008年 | 139篇 |
2007年 | 169篇 |
2006年 | 138篇 |
2005年 | 119篇 |
2004年 | 85篇 |
2003年 | 92篇 |
2002年 | 78篇 |
2001年 | 54篇 |
2000年 | 62篇 |
1999年 | 58篇 |
1998年 | 35篇 |
1997年 | 34篇 |
1996年 | 23篇 |
1995年 | 28篇 |
1994年 | 22篇 |
1993年 | 19篇 |
1992年 | 23篇 |
1991年 | 7篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1986年 | 4篇 |
1984年 | 2篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1975年 | 6篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1972年 | 2篇 |
排序方式: 共有2400条查询结果,搜索用时 15 毫秒
1.
The aim of the research is evaluating the classification performances of eight different machine-learning methods on the antepartum cardiotocography (CTG) data. The classification is necessary to predict newborn health, especially for the critical cases. Cardiotocography is used for assisting the obstetricians’ to obtain detailed information during the pregnancy as a technique of measuring fetal well-being, essentially in pregnant women having potential complications. The obstetricians describe CTG shortly as a continuous electronic record of the baby's heart rate took from the mother's abdomen. The acquired information is necessary to visualize unhealthiness of the embryo and gives an opportunity for early intervention prior to happening a permanent impairment to the embryo. The aim of the machine learning methods is by using attributes of data obtained from the uterine contraction (UC) and fetal heart rate (FHR) signals to classify as pathological or normal. The dataset contains 1831 instances with 21 attributes, examined by applying the methods. In the paper, the highest accuracy displayed as 99.2%. 相似文献
2.
The study examined a decision tree analysis using social big data to conduct the prediction model on types of risk factors related to cyberbullying in Korea. The study conducted an analysis of 103,212 buzzes that had noted causes of cyberbullying and data were collected from 227 online channels, such as news websites, blogs, online groups, social network services, and online bulletin boards. Using opinion-mining method and decision tree analysis, the types of cyberbullying were sorted using SPSS 25.0. The results indicated that the total rate of types of cyberbullying in Korea was 44%, which consisted of 32.3% victims, 6.4% perpetrators, and 5.3% bystanders. According to the results, the impulse factor was also the greatest influence on the prediction of the risk factors and the propensity for dominance factor was the second greatest factor predicting the types of risk factors. In particular, the impulse factor had the most significant effect on bystanders, and the propensity for dominance factor was also significant in influencing online perpetrators. It is necessary to develop a program to diminish the impulses that were initiated by bystanders as well as victims and perpetrators because many of those bystanders have tended to aggravate impulsive cyberbullying behaviors. 相似文献
3.
构建S3C4510B嵌入式系统的开发应用平台 总被引:2,自引:0,他引:2
利用三星公司生产的S3CA510B这款32位ARM7TDMI单片机构建一个应用系统,利用开发软件ARM SDT v2.51,在开发应用系统上实现存储器地址重映射、中断控制、串行通信、液晶、键盘接口。在此基础上,在S3CA510B上嵌入操作系统μC/OS-Ⅱ,用于液晶、键盘接口和多任务管理,为32住单片机的进一步开发应用构造了一个平台。 相似文献
4.
The tree representation of evolutionary relationship oversimplifies the view of the process of evolution as it cannot take into account the events such as horizontal gene transfer, hybridization, homoplasy and genetic recombination. Several algorithms exist for constructing phylogenetic networks which result from events such as horizontal gene transfer, hybridization and homoplasy. Very little work has been published on the algorithmic detail of phylogenetic networks with constrained recombination. The problem of minimizing the number of recombinations in a phylogenetic network, constructed using binary DNA sequences, is NP-hard. In this paper, we propose a pattern recognition-based O(n2) time approach for constructing the phylogenetic network, where n is the number of nodes or sequences in the input data. The network is constructed with the restriction that no two cycles in the network share a common node. 相似文献
5.
The development of autonomous mobile machines to perform useful tasks in real work environments is currently being impeded
by concerns over effectiveness, commercial viability and, above all, safety. This paper introduces a case study of a robotic
excavator to explore a series of issues around system development, navigation in unstructured environments, autonomous decision
making and changing the behaviour of autonomous machines to suit the prevailing demands of users. The adoption of the Real-Time
Control Systems (RCS) architecture (Albus, 1991) is proposed as a universal framework for the development of intelligent systems. In addition it is explained how the use
of Partially Observable Markov Decision Processes (POMDP) (Kaelbling et al., 1998) can form the basis of decision making in the face of uncertainty and how the technique can be effectively incorporated into
the RCS architecture. Particular emphasis is placed on ensuring that the resulting behaviour is both task effective and adequately
safe, and it is recognised that these two objectives may be in opposition and that the desired relative balance between them
may change. The concept of an autonomous system having “values” is introduced through the use of utility theory. Limited simulation
results of experiments are reported which demonstrate that these techniques can create intelligent systems capable of modifying
their behaviour to exhibit either ‘safety conscious’ or ‘task achieving’ personalities. 相似文献
6.
7.
C. C. Price
M. Salama
《Computers & Mathematics with Applications》1993,26(12):17-24Criteria are established to determine the optimal policy for allocating a set of uniform tasks onto a multiprocessor hypercube ensemble. It is shown that the optimal policy depends on the ratio of computation to intertask communication required by the distributed program, and that based on this ratio, tasks should be placed either all on one processor or uniformly distributed over the largest possible hypercube. 相似文献
8.
9.
10.
《四川水力发电》编辑部 《四川水力发电》2006,25(2):77-78
四川水电取得了长足的发展,要坚定不移地发展水电产业,不断完善水电产业发展的机制,抓好移民安置,正确处理好四个关系。 相似文献