首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   782篇
  免费   67篇
  国内免费   4篇
电工技术   1篇
综合类   17篇
化学工业   14篇
机械仪表   4篇
建筑科学   558篇
矿业工程   2篇
能源动力   4篇
轻工业   123篇
水利工程   6篇
石油天然气   44篇
无线电   2篇
一般工业技术   24篇
冶金工业   6篇
原子能技术   2篇
自动化技术   46篇
  2024年   10篇
  2023年   14篇
  2022年   19篇
  2021年   19篇
  2020年   32篇
  2019年   20篇
  2018年   19篇
  2017年   11篇
  2016年   46篇
  2015年   48篇
  2014年   54篇
  2013年   48篇
  2012年   78篇
  2011年   57篇
  2010年   41篇
  2009年   33篇
  2008年   29篇
  2007年   46篇
  2006年   51篇
  2005年   39篇
  2004年   19篇
  2003年   35篇
  2002年   13篇
  2001年   15篇
  2000年   16篇
  1999年   18篇
  1998年   3篇
  1997年   6篇
  1996年   2篇
  1995年   2篇
  1994年   2篇
  1993年   3篇
  1991年   1篇
  1990年   1篇
  1986年   1篇
  1985年   1篇
  1983年   1篇
排序方式: 共有853条查询结果,搜索用时 15 毫秒
1.
The Canadian landscape has typically captured a global imaginary of a pristine wild, but how might its urban designed landscapes be distinctly understood? Foregrounded by the landscape transformations accelerated by climate change, the book Innate Terrain: Canadian Landscape Architecture, edited by Professor Alissa North from the University of Toronto, highlights landscape architecture projects situated on the unique Canadian terrain. Providing further provocation on Canadian landscape architecture, Innate Terrain seeks to fill the literary gap on contemporary landscape perspectives, distinguishing Canadian landscape architecture from global practice, and particularly, its well-documented American counterpart. Landscape architecture in the Canadian context has evolved and established its own distinct identity, one imbued with national and local sensitivities. Informed by diverse environmental and cultural contexts, Canadian-designed landscapes reflect and refer to the prevailing ecosystems of Canada’s innate terrain. Contrary to the preceding International Style, landscape architecture projects in Canada have adopted the ethos of Critical Regionalism in the second half of the 20th century. Contemporary Canadian practitioners are designing landscapes that are deeply informed by their surrounding geographical context while emphasizing cultural specificity. Central to this cultural specificity, addressed by a new generation of landscape architects, is the increasing recognition of Indigenous Traditional Knowledge within the discipline. Canadian landscape architects have collaborated with First Nations, Inuit, and Métis communities, including the keepers of this knowledge, to develop land management strategies and design landscape interventions.  相似文献   
2.
针对领域自适应问题中源域和目标域的联合分布差异最小化问题,提出两阶段领域自适应学习方法.在第一阶段考虑样本标签和数据结构的判别信息,通过学习一个共享投影变换,使投影后的共享空间中边缘分布的差异最小.第二阶段利用源域标记数据和目标域非标记数据学习一个带结构风险的自适应分类器,不仅能最小化源域和目标域条件分布差异,还能进一步保持源域和目标域边缘分布的流形一致性.在3个基准数据集上的实验表明,文中方法在平均分类准确率和Kappa系数两项评价指标上均表现较优.  相似文献   
3.
The aim of the study was to identify the importance of individual food product attributes (the use of preservatives, processing method, shelf-life period and nutritional value) as well as their relation to the purchase behaviour. To achieve this, consumer preferences were decomposed in conditions of full access to information, and data was compared with actual consumer behaviour related to making purchasing decisions in front of the store shelf. Based on data from 338 respondents, conjoint analysis and repeated ANOVA measurements were carried out, allowing to eliminate individual behavioural patterns. The results showed a dissonance between the consumers attitudes towards the attributes and their shopping behaviour. The processing method was the most important declared attribute for consumers, meanwhile this information was the least searched for during purchase. At the same time, shelf-life period marked as the least important was the main information searched for by consumers when shopping. The results also show a clear dislike towards the use of microwaves as a preservation method, while traditional thermal preservation was marked as the most positive for consumers. In addition, consumers were classified into 3 heterogeneous groups, identifying differences in the preferences of food attributes. The obtained results have practical value relating not only to the preferences of individual attributes, but also to their various variants. The results can be a guide for companies to properly label food products. The indicated dissonance illustrates the educational gap and related insufficient motivation to get to know the product before buying it. This is extremely important in connection with technological development and new food processing methods.  相似文献   
4.
ABSTRACT

Galleries, libraries, archives and museums (GLAMs) are increasingly using digital technologies for storytelling and creating mobile applications (apps) for cultural heritage content, but how apps are used in practice to communicate information to users has not been widely studied. A team of people from a heritage organisation, a university, and mobile app development group plan to create a bespoke heritage trail app for Ireland, but to date design conventions/recommendations for this genre are lacking. This article applies a systematic approach to digital narrative content analysis to better understand how apps are being used specifically for heritage trails with the aim of identifying what the common features are, which modalities and narrative techniques are used. The selected corpus included 55 apps downloaded from the Google Play Store. The results of this content analysis—based on the App Walkthrough Method (Light, B., Burgess, J., & Duguay, S. (2018). The walkthrough method: An approach to the study of apps. New Media & Society, 20(3), 881–900)—show that there is a gap between academic research themes/trends and how digital narrative is actually being communicated in the current market, and it aims to inform the future development of heritage trail apps by including a list of design and content features common to this genre.  相似文献   
5.
摘 要:目的 探究低温等离子体(cold plasma, CP)处理模式对冷藏南美白对虾中常见荧光假单胞菌(Pseudomonas fluorescens)的抑菌效果及其作用机制。方法 通过CP直接处理和循环处理P. fluorescens,研究了两种处理模式下臭氧含量动态变化对P. fluorescens的生长曲线、细胞活力,生物膜形成、细胞壁、细胞膜完整性和南美白对虾菌落总数及假单胞菌数等指标的影响。结果 两种处理模式在CP处理3 min或3 cycles后,包装内臭氧含量达到最高值,分别为(850±10) mg/m3和(874±20) mg/m3。CP循环处理模式使得臭氧含量随处理循环数递增,因此获得更长的臭氧存在时间从而具有更大的抑菌能力。P. fluorescens生长曲线表明CP处理使得菌体延迟期变长且对数生长期推迟。此外,CP处理后的P. fluorescens细胞活力显著下降(P<0.05),CP-1 min,CP-3 min和CP-3 cycles组的细胞活力分别为33.03%、5.90%和4.82%。同时相比CP-3 min组,CP-3 cycles组的P. fluorescens生物膜OD值下降27.61%。碱性磷酸酶(alkaline phosphatase, AKP)活性和核酸蛋白泄漏量结果表明,细胞壁和细胞膜完整性受损可能是P. fluorescens失活的直接原因。对虾保鲜测试结果证实,贮藏第6 d,CP-3 cycles组虾体中的菌落总数和假单胞菌数相比CP-3 min组分别降低了58.02%和79.54%。结论 CP循环处理模式通过延长对臭氧与对虾的暴露时间,提高了对P. fluorescens的灭活效果,同时还具有更优越的保鲜能力。本研究为开发基于CP技术的新型保鲜技术应用提供了理论参考。 关键词:低温等离子体;荧光假单胞菌;抑菌机制;保鲜  相似文献   
6.
文章从现代审美视角出发,结合前人的研究论证,探讨与补充非遗文创在品牌视觉设计及包装插画方面研究的理论不足,为设计者提供更加开阔的设计思路和更为新颖的设计手法,从而提升非遗文创的整体设计效果。  相似文献   
7.
8.
四川盆地东南地区龙马溪组页岩气有效保存区综合评价   总被引:12,自引:0,他引:12  
受差异构造边界的制约,四川盆地东南地区(简称川东南)中新生代发生差异构造变形,使得保存条件成为控制该区下古生界页岩气富集的主要因素。为此,从制约保存条件的直接原因——构造作用出发,对该区页岩气保存条件进行了综合评价。首先以构造研究为先导,立足于中新生代差异构造变形方式和强度,将评价区划分为7个构造形变带,并对各构造形变带的断裂规模、断裂密度、顶底板岩性和厚度、目的层埋深、构造形态和裂缝间距指数等影响因素进行系统揭示,确立页岩气有效保存区的评价指标和标准,建立页岩气保存条件综合评价体系。在此基础上,依据该区页岩气保存条件最优评价参数标准,对7个构造形变带下志留统龙马溪组页岩气的保存条件进行了宏观评价。结果表明:齐岳山断裂以西地区的保存条件整体上好于东侧;齐岳山断裂以东地区,以武隆断褶带的保存条件为最好,其次为彭水断褶带和黔江断褶带,道真叠加断褶带、务川叠加断褶带和沿河叠加断褶带相对较差。  相似文献   
9.
身份之场所     
城市是人类创造的适于居住的区域性的人工生态系统,其主干结构是公共空间系统。公共空间,亦即如是所说的公共城市空间,为所有公民所有,因此,它必须毫无例外地面向每个人,其所有权、领域及使用必须是公共的。这种公共空间是文化与社会的支撑,赋予公民团体以身份。它是同存共生的景致,是集会社交的场所,调控个中的私密功能以维系此般公共空间的权益尤显必要。因为代表了公民团体的身份,公共空间成为一种象征性的场所,其身份的表现为人所知并被传承。  相似文献   
10.
武当山是中国重要的道教圣地,园林营建活动历史悠久、空间广袤、建造技术精湛,达到了皇家所要求的宏伟、威严和道教所追求的玄妙、超然,是人文美与自然美的高度统一。本文通过对世界遗产武当山文化景观的概述,认为武当山是人类文化的见证和古代科学技术的典范,也是我们建设山地人居环境的生动教材。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号