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31.
This study examined whether the socioemotional health of children 9–12 years old is related to the physical quality of their residence and neighborhood. The study included 95 children from households with a wide range of incomes in a medium-sized anglophone and a medium-sized francophone Canadian city. Each childȁ9s socioemotional health was assessed and the quality of each childȁ9s housing was assessed on up to 309 aspects of the residence and immediate neighborhood, based on walk-throughs and interviews with the parents in the residences. The childrenȁ9s socioemotional health, as assessed by their parents, was worse when the physical condition of their residenceȁ9s interior, exterior, and immediate neighborhood was worse. This relation remained significant after controlling for household income, parental education and mental health status, the childȁ9s gender, and time lived in the residence. Furthermore, none of these five factors moderated the relation, evidence for its robustness.  相似文献   
32.
The case for the universal application of 'safer surfacing' in playgrounds is assessed in terms of absolute risk, cost-benefit, and qualitative factors, and found to be open to question on each front. In parallel, it is noted that members of the child welfare and play communities are increasingly of the view that playgrounds are losing their appeal for children, which in turn has its own health, safety and developmental consequences. In part, this loss of attractiveness may have linkages with the recent concern over play safety and the imposition of measures such as 'safer surfacing'. It is proposed that the drive for play safety, which has existed for some 20 years, should be succeeded by a more holistic approach which, rather than considering play safety in isolation, acknowledges the importance of all attributes of play including child safety both on and off playgrounds, potential beneficial aspects of childhood risk exposure, adventure, and play value.  相似文献   
33.
This article provides a historical overview of educational computing research at MIT from the mid-1960s to the present day, focusing on physical interfaces. It discusses some of the results of this research: electronic toys that help children develop advanced modes of thinking through free-form play. In this historical context, the article then describes and discusses the authors own research into tangible programming, culminating in the development of the Tangible Programming Bricks system—a platform for creating microworlds for children to explore computation and scientific thinking.
Timothy S. McNerneyEmail: Phone: +1-781-8393210Fax: +1-781-8902201
  相似文献   
34.
Neural networks with fixed input length are not able to train and test data with variable lengths in one network size. This issue is very crucial when the neural networks need to deal with signals of variable lengths, such as speech. Though various methods have been proposed in segmentation and feature extraction to deal with variable lengths of the data, the size of the input data to the neural networks still has to be fixed. A novel Self-Adjustable Neural Network (SANN) is presented in this paper, to enable the network to adjust itself according to different data input sizes. The proposed method is applied to the speech recognition of Malay vowels and TIMIT isolated words. SANN is benchmarked against the standard and state-of-the-art recogniser, Hidden Markov Model (HMM). The results showed that SANN was better than HMM in recognizing the Malay vowels. However, HMM outperformed SANN in recognising the TIMIT isolated words.  相似文献   
35.
Cadmium levels were determined in 59 baby food samples, including milk-based, cereal and milk-based and soy-based formulas, recommended from 0 to 18 months of age. Determinations were performed by Zeeman graphite furnace atomic absorption spectrophotometry, after dry ashing, with parallel determinations of certified reference samples. Mean cadmium levels were found to range from 1.10 to 23.5 mu g / kg fresh weight concentrated formulas. L evels were related to the composition of the diets. Formulas based on cow's milk had the lowest concentrations. Soy formulas contained approximately six times more cadmium than cow's milk formulas, and diets with a cereal content had 4-21 times higher mean levels. The mean weekly intakes of dietary cadmium were estimated to vary between 0.10 and 3 : 05 mu g / kg body weight of the child, if the recommended amount of formula were to be consumed at the recommended age, and if the child were of average weight. This estimation however does not include the contribution of cadmium from drinking water. The highest intake on a body weight basis was found in 6-month-old children, consuming the recommended amount of wheat-, oat- and milk-based formulas. This intake is below the provisional tolerable weekly intake (PTW I) of 7 mu g / kg body weight, established by a W HO/FAO expert group. However, the risk assessment is based on renal effects in adults. Furthermore, preparations of a formula by adding water with cadmium concentrations at the W HO guideline level could lead to intakes at the PTW I level. Compared to breast-fed children, the exposure of dietary cadmium from weaning diets can be up to 12 times higher in children fed infant formula.  相似文献   
36.
A fortified food that was rich in protein, vitamins and iron made of chickpea, bovine lung and corn was developed with the aim of controlling iron-deficiency anaemia in children from poorer areas. It was tested in Teresina, State of Piauí, Northeastern Brazil, on a population with high anaemia prevalence. Two local daycare units with similar characteristics were selected and the children at one of them received a 30 g pack three times a week, representing a total iron daily intake of 6.96 mg. The other daycare unit was followed as a control. The capillary haemoglobin concentration was determined for the children at both daycare units, at the beginning of the study and after a two-month intervention period. The mean haemoglobin concentration in the test group at the beginning of the intervention was 11.8 g/dL, which increased to 13.1 g/dL at the end of the intervention. In the control group these figures remained practically constant (11.6–11.8 g/dL). These represented a dramatic and significant drop in anaemia prevalence, from 61.5% to 11.5% in the test group, and an insignificant reduction (63.1–57.7%) in the control group. The acceptance of the fortified snack was excellent and no undesirable effects were observed.  相似文献   
37.
This article deals with how a female member of the elite from the period of the Portuguese dictatorial regime (1933–1974) used Lisbon’s gardens to implement a free childhood education and assistance programme for poor children – the Children’s Parks programme. The Children’s Parks were located in some of Lisbon’s most attractive gardens, housed in pavilions that were directly connected to outdoor spaces. These spaces responded to the educational purposes of the programme, based on the importance of leisure and play activities in outdoor spaces and linked to children’s moral, social, and physical development. In considering the living conditions experienced by children within the context of the Portuguese dictatorship, and by highlighting the way in which these were reflected at the level of architecture and the urban space, the paper seeks to contribute towards an understanding of the place of the child in the history of architecture and urbanism. Besides reflecting the social and educational identity of the project, the urban and architectural settings of the programme were crucial for its success. The interpretation of this case provides a basis for reflecting on the historical and current significance of children’s spaces, and for examining a number of social, educational, architectural, and urban questions.  相似文献   
38.
游戏是儿童成长中不可或缺的部分,儿童友好城市的重要硬件措施是建设儿童游戏据点。冒险游戏场作为代表性场所,在治愈儿童心理问题、培养儿童责任感、激发儿童危机意识和自我保护技能等方面发挥了重要作用。冒险游戏场在国外已有70余年的实践历史,但我国对冒险游戏场的研究尚处于初级阶段,在实践方面仍属空白。本文从剖析冒险游戏场的起源与核心思想入手,重点围绕欧美和日本的发展背景,对其发展历史进行系统梳理,再深入解读"常设"和"非常设"的三个典型案例,总结出设计理念"自由化"、空间要素"自然化"、场所运营"专业化"三个关键启示,为我国儿童公共空间的研究提供借鉴和参考。  相似文献   
39.
Arsenic is naturally associated with gold mineralisation and elevated in some soils and mine waste around historical gold mining activity in Victoria, Australia. To explore uptake, arsenic concentrations in children's toenail clippings and household soils were measured, and the microdistribution and speciation of arsenic in situ in toenail clipping thin sections investigated using synchrotron-based X-ray microprobe techniques. The ability to differentiate exogenous arsenic was explored by investigating surface contamination on cleaned clippings using depth profiling, and direct diffusion of arsenic into incubated clippings. Total arsenic concentrations ranged from 0.15 to 2.1 µg/g (n = 29) in clipping samples and from 3.3 to 130 µg/g (n = 22) in household soils, with significant correlation between transformed arsenic concentrations (Pearson's r = 0.42, P = 0.023) when household soil was treated as independent. In clipping thin sections (n = 2), X-ray fluorescence (XRF) mapping showed discrete layering of arsenic consistent with nail structure, and irregular arsenic incorporation along the nail growth axis. Arsenic concentrations were heterogeneous at 10 × 10 µm microprobe spot locations investigated (< 0.1 to 13.3 µg/g). X-ray absorption near-edge structure (XANES) spectra suggested the presence of two distinct arsenic species: a lower oxidation state species, possibly with mixed sulphur and methyl coordination (denoted As≈ III(-S, -CH3)); and a higher oxidation state species (denoted As≈ V(-O)). Depth profiling suggested that surface contamination was unlikely (n = 4), and XRF and XANES analyses of thin sections of clippings incubated in dry or wet mine waste, or untreated, suggested direct diffusion of arsenic occurred under moist conditions. These findings suggest that arsenic in soil contributes to some systemic absorption associated with periodic exposures among children resident in areas of historic gold mining activity in Victoria, Australia. Future studies are required to ascertain if adverse health effects are associated with current levels of arsenic uptake.  相似文献   
40.
Japanese cedar pollinosis (JCP) caused by allergenic cedar and cypress pollens is one of major economic and health issues in Japan. The present study reported here aimed to provide basic data to understand the status of early life exposures to airborne cedar and cypress pollens in school settings. In particular, the study investigated relationships between indoor and outdoor concentrations of airborne cedar and cypress pollens and total suspended particulates (TSP) in a kindergarten in Japan. Overall, outdoor concentrations of the airborne pollens and TSP were higher than the indoor concentrations, i.e., indoor to outdoor (I/O) ratios of 0.043–0.055 and 0.545 for the airborne pollens and TSP, respectively. The smaller I/O ratios for the pollens were expected because the larger pollen grains (20–30 μm in diameter) were less likely penetrated to indoor environment than for smaller airborne particulates. The present study also found increased TSP concentrations during the pollen season was likely attributed to increased airborne pollen concentrations. By understanding the status of indoor and outdoor concentrations of airborne cedar and cypress pollens in school settings, early life exposures to these allergenic pollens should be effectively minimized to prevent subsequent progression to JCP symptoms.  相似文献   
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