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31.
The optimal control of inventory in supply chains plays a key role in the competiveness of a corporation. The inventory cost can account for half of company’s logistics cost. The classical inventory models, e.g., newsvendor and EOQ models, assume either a single or infinite planning periods. However, these models may not be applied to perishable products which usually have a certain shelf life. To optimize the total logistic cost for perishable products, this paper presents a multi-period newsvendor model, and the problem is formulated as a multi-stage stochastic programming model with integer recourse decisions. We extend the progressive hedging method to solve the model efficiently. A numerical example and its sensitivity analysis are demonstrated.  相似文献   
32.
Raising water demands and insufficient freshwater resources are the main reasons of water conflicts in transboundary watersheds. Sustainable water allocation can be a resolution for water disputes as it addresses simultaneously economic, social and environmental benefits. In this paper, a multi-objective model is introduced, which leads to sustainable water allocation of transboundary watersheds taking into account all these three aspects. Five water allocation objectives are proposed for this model in which three of them address the social factors and others represent the economic and environmental preferences. The Compromise Programming technique is employed to solve the applied model to the Sefidrud Basin, Iran and several water allocation schemes are provided based on various weights combinations. The results of the model elucidate that the proposed model can allocate 83 percent of the Basin's water resources, to its stakeholders in a sustainable way while the environmental demand is satisfied.  相似文献   
33.
The supplier–buyer coordination is an important policy in the supply chain management. The buyer in the two-echelon inventory system with regular selling season has to face the uncertainty of customer demand, supplier’s delivery time and variable price change. At the same time, the supplier has to consider the inventory holding and delay cost. The objective of this study is to develop an integrated supply chain strategy for products with short lifecycle and variable selling price to entice cooperation. The strategy must provide a win–win situation for both the supplier and the buyer. A numerical case example, sensitivity analysis and compensation mechanism are given to illustrate the model.  相似文献   
34.
Allowing users to actively participate in the development and implementation of a new IS is supposed to increase their satisfaction with it. This type of participation, representing aspects relating to distributive and procedural justice, is increasingly impractical in current organizational settings, because many IS are used by thousands of employees and having them involved is impossible. Nonetheless, there are still benefits to be gained in other ways. Extrapolating from interactional justice, we proposed a passive participation method of engaging users. Its effect was tested in a large company in the USA and proved effective. Interactional justice, the perception of fairness in the way that people were treated at an interpersonal level, was found to increase user assessment of the value of their IS. Implications and expansions to interactional justice theory and how this antecedent affects IS implementation are discussed.  相似文献   
35.
This paper presents suggestions for a more pragmatic approach to the design of emerging and future domestic communication technologies, particularly technologies destined for the home that may be deemed ‘ubiquitous’. This is achieved through two critical reviews of a small number of social studies related to the design and use of existing and emerging communication technologies. The first review explores how existing, recent and emerging technologies are adopted within the domestic home and explores how social patterns dictate adoption. The second review draws more broadly on research activity related to the design and development of ubiquitous technologies for everyday life and what lessons can be learnt from them. Together, these two reviews suggest novel communication technology adoption will evolve through small imperceptible steps from the edges of existing products and services; therefore design research needs to be more aligned to this approach. To make any real impact and influence, research activity needs to move away from attempts to deliver ubiquity in the home and place more emphasis at the pragmatic, incremental level of emerging communication services and products.  相似文献   
36.
This study modelled the rational factors that predict fake news sharing behaviour. It also tested the moderating role of social media literacy skills. The focus was on social media users in Nigeria. An online survey was conducted to gather the responses from participants across Nigerian geopolitical zones. Structural equation modelling (SEM) Smart PLS 3.6 was used to analyse the data. We found that information sharing, the news finds me perception, trust in social media and status-seeking lead to fake news sharing among social media users in Nigeria. Specifically, trust in social media and status-seeking had a greater effect on fake news sharing behaviour. We also found that social media literacy skills significantly moderate the relationship between information sharing, status-seeking, the news finds me perception, trust in social media and fake news sharing in such a way that the effects/relationships are stronger among those with low social media literacy skills. This outcome contributes to theory and practice which was highlighted in the concluding aspect of this study.  相似文献   
37.
Many companies are using social media as emerging marketing channels in hopes of encouraging engagement by customers. This study explored the effect of multiple social media post cues on customer engagement. By distinguishing WeChat posts’ characteristics into outer- and inner-layer features, the findings suggest that outer-layer features (title linguistic vividness and top position) have positive effects on reads, and inner-layer features (post vividness and containing user-generated content) encouraged more likes, shares, and comments. In addition, by assigning post contents into sales and non-sales-related categories, we found the former attracts more comments and the latter is more helpful in promoting likes and shares. Further, within sales-related posts, storytelling category will receive more likes, whereas functional category boosts the number of shares.  相似文献   
38.
蒋杰辉  盛典  杨鹏 《控制与决策》2023,38(6):1695-1702
交通运输系统在服务民众的同时也为疫情沿跨区域传播扩散提供了载体.鉴于此,研究疫情沿多种交通工具跨区域扩散模型及最优控制问题.考虑人口空间状态、迁徙过程、疫情状态和交通工具特征,构建多区域迁徙-疫情扩散耦合动力学方程,并分析其扩散性质.综合考虑应急资源的有限性,进一步建立基于本地与迁徙隔离政策的动态最优控制模型.数值计算对比分析不同管控策略组合下疫情的扩散速度与范围,验证疫情扩散模型和最优控制策略的有效性.结果表明:疫情可以借助交通工具快速扩散;仅对单一交通工具实施管控措施可以快速降低疫情跨区域扩散的速度,但对均衡状态的扩散范围影响小.  相似文献   
39.
Waiting time appears to be an unavoidable part of the service industry, particularly at the airport, where you may encounter delays due to check-in, screening, and other activities. This waiting experience can vex customers, affecting their perception of the service provider and, consequently, their loyalty. Our study aimed to determine the effect of waiting time satisfaction and the use of self-service technology on the long-term sustainability of customer loyalty. 750 structured questionnaires were distributed to travelers at two international airports in Turkey. PLS-SEM was used to analyses the models. Our findings indicate that customer satisfaction with waiting times and the use of self-service technologies are critical for the long-term sustainability of customer loyalty. Additionally, we discovered that waiting time satisfaction partially mediates the relationship between self-service technology use and long-term customer loyalty. Finally, the managerial implications were discussed, including future research suggestions.  相似文献   
40.
Generalized additive models (GAMs) are a generalization of generalized linear models (GLMs) and constitute a powerful technique which has successfully proven its ability to capture nonlinear relationships between explanatory variables and a response variable in many domains. In this paper, GAMs are proposed as base classifiers for ensemble learning. Three alternative ensemble strategies for binary classification using GAMs as base classifiers are proposed: (i) GAMbag based on Bagging, (ii) GAMrsm based on the Random Subspace Method (RSM), and (iii) GAMens as a combination of both. In an experimental validation performed on 12 data sets from the UCI repository, the proposed algorithms are benchmarked to a single GAM and to decision tree based ensemble classifiers (i.e. RSM, Bagging, Random Forest, and the recently proposed Rotation Forest). From the results a number of conclusions can be drawn. Firstly, the use of an ensemble of GAMs instead of a single GAM always leads to improved prediction performance. Secondly, GAMrsm and GAMens perform comparably, while both versions outperform GAMbag. Finally, the value of using GAMs as base classifiers in an ensemble instead of standard decision trees is demonstrated. GAMbag demonstrates performance comparable to ordinary Bagging. Moreover, GAMrsm and GAMens outperform RSM and Bagging, while these two GAM ensemble variations perform comparably to Random Forest and Rotation Forest. Sensitivity analyses are included for the number of member classifiers in the ensemble, the number of variables included in a random feature subspace and the number of degrees of freedom for GAM spline estimation.  相似文献   
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