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1.
Multimedia content has been growing quickly and video retrieval is regarded as one of the most famous issues in multimedia research. In order to retrieve a desirable video, users express their needs in terms of queries. Queries can be on object, motion, texture, color, audio, etc. Low-level representations of video are different from the higher level concepts which a user associates with video. Therefore, query based on semantics is more realistic and tangible for end user. Comprehending the semantics of query has opened a new insight in video retrieval and bridging the semantic gap. However, the problem is that the video needs to be manually annotated in order to support queries expressed in terms of semantic concepts. Annotating semantic concepts which appear in video shots is a challenging and time-consuming task. Moreover, it is not possible to provide annotation for every concept in the real world. In this study, an integrated semantic-based approach for similarity computation is proposed with respect to enhance the retrieval effectiveness in concept-based video retrieval. The proposed method is based on the integration of knowledge-based and corpus-based semantic word similarity measures in order to retrieve video shots for concepts whose annotations are not available for the system. The TRECVID 2005 dataset is used for evaluation purpose, and the results of applying proposed method are then compared against the individual knowledge-based and corpus-based semantic word similarity measures which were utilized in previous studies in the same domain. The superiority of integrated similarity method is shown and evaluated in terms of Mean Average Precision (MAP).  相似文献   
2.
Data transformation is the core process in migrating database from relational database to NoSQL database such as column-oriented database. However, there is no standard guideline for data transformation from relational database to NoSQL database. A number of schema transformation techniques have been proposed to improve data transformation process and resulted better query processing time when compared to the relational database query processing time. However, these approaches produced redundant tables in the resulted schema that in turn consume large unnecessary storage size and produce high query processing time due to the generated schema with redundant column families in the transformed column-oriented database. In this paper, an efficient data transformation technique from relational database to column-oriented database is proposed. The proposed schema transformation technique is based on the combination of denormalization approach, data access pattern and multiple-nested schema. In order to validate the proposed work, the proposed technique is implemented by transforming data from MySQL database to HBase database. A benchmark transformation technique is also performed in which the query processing time and the storage size are compared. Based on the experimental results, the proposed transformation technique showed significant improvement in terms query processing time and storage space usage due to the reduced number of column families in the column-oriented database.  相似文献   
3.
Retrieving the most relevant video frames that contain the object specified in a given query (query-by-region) remains a challenging task. Two common challenges of region-based retrieval approaches are to accurately extract or segment object(s) and select a proper matching strategy. This paper addresses these problems by proposing a retrieval approach that uses a new region-based matching technique equipped with an effective object representation method. In the first stage, the proposed approach selects the most informative instances of each object that appeared in the video by utilizing an adapted clustering algorithm over the extracted features. In the retrieval stage, the new matching technique returns the most relevant sequences of video by mapping a given region with those identified representative instances of objects based on their similarity scores. The proposed approach is evaluated on standard datasets and the results demonstrate a 31% improvement in the retrieval performance compared to other state-of-the-art methods.  相似文献   
4.
Spent brewers' or distillers' grains are normally disposed of either in the wet form, in which they spoil rapidly, or after drying, which is costly. Alternatively, the storage life of wet grains may be extended by ensiling, which involves on-farm control and equipment. This investigation examines the preservation of spent grains by lowering the water activity of the material using molasses and further stabilising the mixture by incorporating an anti-mycotic agent. Investigations at both laboratory-scale and pilot-scale are reported culminating in the successful stabilisation of the wet grains by the incorporation of 30% of beet molasses and 0.3% of potassium sorbate into the grains after preliminary centrifugation. For effective preservation the stabilised grains should be consolidated in plastic bags followed by closing to leave the minimum possible headspace in the bags.  相似文献   
5.
Judgement skills and critical thinking in dentistry are developed through: (1) a systematic approach to gathering and processing information, and (2) an essential amount of practical experience. A new system of interactive videodisc patient simulations titled 'Dental Diagnosis and Treatment' or 'DDx & Tx' has been developed to provide students or practicing dentists an opportunity to develop and practice their critical thinking skills. The DDx & Tx system consists of patient simulation software, a laser-reflective videodisc with its accompanying database, a patient simulation management system, and documentation. An authoring tool is under development. Faculty-authored simulations require students to gather information, formulate diagnoses, order appropriate treatments and properly sequence those treatments. The students' performance is automatically scored and a critique is provided as a review.  相似文献   
6.
Lilly  C.J. 《IEE Review》1990,36(3):111-113
The author gives a brief history of the Intelsat satellites and then discusses the requirements for the seventh generation of satellites. These satellites are needed in the Pacific Ocean region and the Atlantic Ocean region. The main coverage features are briefly discussed. The Intelsat VII series are smaller than the Intelsat VI series and have fewer transponders. The main components and construction of the satellites is discussed  相似文献   
7.
Nitrous oxide (N2O) is a powerful greenhouse gas. As the UK government is committed to reducing greenhouse gas emissions, it is important to know not only how much of these gases are released but also where and when. Targeted measurements of emissions in relation to crop growth cycles, soil wetness and fertiliser applications were used to derive annual emission rates for specific combinations of soil type, land management and fertiliser practices. These annual emission rates were then spatially scaled to derive regional figures through the development of a Geographic Information System (GIS) based model framework. Digital soil and land use maps at a scale of 1:25000 for two test areas of approximately 200000 ha each (Lothians and the Ayrshire Basin) were overlain with a climate map within the GIS, deriving unique combinations of soil wetness and land use. The calculated annual emission rates (kg N ha–1 yr–1) were then applied to these and multiplied by the total area of each soil/land use type to derive annual emission losses for each area. The annual emission of nitrous oxide from the Lothians was determined as approximately 381000 kg N yr–1, while the emissions from the Ayrshire Basin were predicted to be 794000 kg N yr–1. This indicates the increased emissions associated with both the wetter soils of Ayrshire and the greater extent of grazed pasture systems in this area. Due to the detailed scale of the input data, localised areas with large emissions were identified. Abatement strategies would be concentrated on areas of high emissions that include a change to crops with lower emission potential, reducing fertiliser and manure inputs, reducing grazing intensity and improving soil drainage.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1024422604493  相似文献   
8.
In contrast to the conventional DSSC systems, where the dye molecules are used as light harvesting material, here a solid-state absorber was used as a sensitizer in conjunction with the dye. The materials like ZnO and Al2O3 : C, which will show optically stimulated luminescence (OSL) upon irradiation were used as extremely thin absorber layers. This novel architecture allows broader spectral absorption, an increase in photocurrent, and hence, an improved efficiency because of the mobility of the trapped electrons in the absorber material after irradiation, to the TiO2 conduction band. Nanocrystalline mesoporous TiO2 photoanodes were fabricated using these solid-state absorber materials and after irradiation, a few number of samples were co-sensitized with N719 dye. On comparing both the dye loaded photoanodes (ZnO/TiO2 and Al2O3 : C/TiO2), it can be concluded from the present studies that, the Al2O3 : C is superior to ZnO under photon irradiation. Al2O3 : C is more sensitive to photon irradiation than ZnO and hence there can be more trap centres produced in Al2O3 : C.  相似文献   
9.
The California Energy Commission has recognized evaporative cooling space conditioning as a key demand-side “Opportunity Technology,” which offers compelling energy, economic development and environmental benefits to the state. In 1993, the Commission lead an effort to form an industry Collaborative of Stakeholders whose primary focus was to improve market penetration through the identification and elimination of the key barriers to technology deployment. More recently, the Commission has supported this objective through the funding of a statewide market assessment of evaporative cooling in the residential and commercial market segments with Regional Economic Research, Inc. of San Diego, California under Contract No. 500-93-027. Summary data and results from this work are presented in this paper.Baseline forecasts of market shares and the associated energy impacts within the residential and commercial market segments, including new construction and existing facilities, were then developed for each statewide planning area and utility climate zone in California. Thereafter, forecasts of the sensitivity of market shares and energy impacts to changes in key drivers (e. g., awareness, technology costs, and select non-economic drivers) were generated to establish the relative importance of each of the technology market drivers. Finally, Achievable Potential was estimated in the form of market shares and associated energy savings, based upon assumptions with respect to the achievable reductions in evaporative cooling deployment barriers.  相似文献   
10.
To investigate the relationship of severity of pediatric closed head injury (CHI), the contribution of frontal lobe lesions, and age at testing (6–10 yr olds vs 11–15 yr olds) to cognitive deficit, 134 head-injured patients were given the Tower of London (TOL) task and underwent magnetic resonance imaging. 89 normal controls were given the TOL for comparison. Severity of CHI and age at testing were strongly related to cognitive performance on the TOL, including the frequency of breaking the rules. Volume of frontal lobe lesion (but not extrafrontal lesion) contributed to the prediction of perfomance on the TOL even after severity of injury was taken into account. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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