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1.
Sta?a Milojevi? 《Journal of nanoparticle research》2012,14(1):685-28
This article examines the cognitive evolution and disciplinary diversity of nanoscience/nanotechnology (nano research) as
expressed through the terminology used in titles of nano journal articles. The analysis is based on the NanoBank bibliographic
database of 287,106 nano articles published between 1981 and 2004. We perform multifaceted analyses of title words, focusing
on 100 most frequent words or phrases (terms). Hierarchical clustering of title terms reveals three distinct time periods
of cognitive development of nano research: formative (1981–1990), early (from 1991 to 1998), and current (after 1998). Early
period is characterized by the introduction of thin film deposition techniques, while the current period is characterized
by the increased focus on carbon nanotube and nanoparticle research. We introduce a method to identify disciplinary components of nanotechnology. It shows that the nano research is being carried out in a number of diverse parent disciplines. Currently, only 5% of articles are published in dedicated nano-only journals. We find that some 85% of nano
research today is multidisciplinary. The case study of the diffusion of several nano-specific terms (e.g., “carbon nanotube”)
shows that concepts spread from the initially few disciplinary components to the majority of them in a time span of around
a decade. Hierarchical clustering of disciplinary components reveals that the cognitive content of current nanoscience can
be divided into nine clusters. Some clusters account for a large fraction of nano research and are identified with such parent
disciplines as the condensed matter and applied physics, materials science, and analytical chemistry. Other clusters represent
much smaller parts of nano research, but are as cognitively distinct. In the decreasing order of size, these fields are: polymer
science, biotechnology, general chemistry, surface science, and pharmacology. Cognitive content of research published in nano-only
journals is the closest to nano research published in condensed matter and applied physics journals. 相似文献
2.
John M. Balbus Karen Florini Richard A. Denison Scott A. Walsh 《Journal of nanoparticle research》2007,9(1):11-22
Nanotechnology, the design and manipulation of materials at the atomic scale, may well revolutionize many of the ways our
society manufactures products, produces energy, and treats diseases. New materials based on nanotechnology are already reaching
the market in a wide variety of consumer products. Some of the observed properties of nanomaterials call into question the
adequacy of current methods for determining hazard and exposure and for controlling resulting risks. Given the limitations
of existing regulatory tools and policies, we believe two distinct kinds of initiatives are needed: first, a major increase
in the federal investment in nanomaterial risk research; second, rapid development and implementation of voluntary standards
of care pending development of adequate regulatory safeguards in the longer term. Several voluntary programs are currently
at various stages of evolution, though the eventual outputs of each of these are still far from clear. Ultimately, effective
regulatory safeguards are necessary to provide a level playing field for industry while adequately protecting human health
and the environment. This paper reviews the existing toxicological literature on nanomaterials, outlines and analyzes the
current regulatory framework, and provides our recommendations, as an environmental non-profit organization, for safe nanotechnology
development. 相似文献
3.
Jiyoun Kim Heather Akin Dominique Brossard Michael Xenos Dietram A. Scheufele 《Journal of nanoparticle research》2017,19(5):167
This study examines how familiarity with an issue—nanotechnology—moderates the effect of exposure to science information on how people process mediated messages about a complex issue. In an online experiment, we provide a nationally representative sample three definitions of nanotechnology (technical, technical applications, and technical risk/benefit definitions). We then ask them to read an article about the topic. We find significant interactions between perceived nano-familiarity and the definition received in terms of how respondents perceive favorable information conveyed in the stimulus. People less familiar with nanotechnology were more significantly affected by the type of definition they received. 相似文献
4.
《Nuclear Physics A》1986,455(4):573-583
5.
本文构造了一个基于在线社交网络的信息传播模型.该模型考虑了节点度和传播机理的影响,结合复杂网络和传染病动力学理论,进一步建立了动力学演化方程组.该方程组刻画了不同类型节点随着时间的演化关系,反映了传播动力学过程受到网络拓扑结构和传播机理的影响.本文模拟了在线社交网络中的信息传播过程,并分析了不同类型节点在网络中的行为规律.仿真结果表明:由于在线社交网络的高度连通性,信息在网络中传播的门槛几乎为零;初始传播节点的度越大,信息越容易在网络中迅速传播;中心节点具有较大的社会影响力;具有不同度数的节点在网络中的变
关键词:
在线社交网络
信息传播
微分方程
传染病动力学 相似文献
6.
The North American opinion climate for nanotechnology and its products: Opportunities and challenges
Susanna Priest 《Journal of nanoparticle research》2006,8(5):563-568
A January 2005 telephone survey of 1200 people in the U.S. and 2000 Canadians provides a snapshot of current North American opinion regarding nanotechnology at this crucial early point in its emergence from the laboratory to the arena of public discourse and public understanding. Using a typology of “publics” developed through analysis of a previous comparative survey (Priest, S., 2006) and subsequently tested against these newer data (Priest, S., 2005) this article describes the opinion climate for nanotechnology across North America. The comparison of key results from the two countries helps illustrate how social and cultural differences contribute to reactions to new technologies, including nanotech. The article also discusses implications for nanotechnology-related public outreach and risk communication efforts. 相似文献
7.
Inverse statistics analysis studies the distribution of investment horizons to achieve a predefined level of return. This distribution provides a maximum investment horizon which determines the most likely horizon for gaining a specific return. There exists a significant difference between inverse statistics of financial market data and a fractional Brownian motion (fBm) as an uncorrelated time-series, which is a suitable criteria to measure information content in financial data. In this paper we perform this analysis for the DJIA and S&P500 as two developed markets and Tehran price index (TEPIX) as an emerging market. We also compare these probability distributions with fBm probability, to detect when the behavior of the stocks are the same as fBm. 相似文献
8.
Patents are an essential information source used to monitor, track, and analyze nanotechnology. When it comes to search nanotechnology-related patents, a keyword search is often incomplete and struggles to cover such an interdisciplinary discipline. Patent classification schemes can reveal far better results since they are assigned by experts who classify the patent documents according to their technology. In this paper, we present the most important classifications to search nanotechnology patents and analyze how nanotechnology is covered in the main patent classification systems used in search systems nowadays: the International Patent Classification (IPC), the United States Patent Classification (USPC), and the Cooperative Patent Classification (CPC). We conclude that nanotechnology has a significantly better patent coverage in the CPC since considerable more nanotechnology documents were retrieved than by using other classifications, and thus, recommend its use for all professionals involved in nanotechnology patent searches. 相似文献
9.
10.
Johannes Simons René Zimmer Carl Vierboom Ingo H?rlen Rolf Hertel Gaby-Fleur B?l 《Journal of nanoparticle research》2009,11(7):1555-1571
According to numerous surveys the perceived risk of nanotechnology is low and most people feel that the benefits outweigh
the risks. This article provides greater insight into risk perception and concludes that the positive attitude to nanotechnology
is based not on knowledge but on hope and fascination. The perceived risk is low because of a lack of vivid and frightening
images of possible hazards. If news flashes were to link nanotechnology to concrete hazards or actual harm to people, attitudes
might suddenly change. Risk communication faces the problem of dealing with a public at large that has little or no knowledge
about the technology. As it takes time and extensive additional research to develop appropriate communication strategies and
disseminate them to the relevant institutions, this exercise should be started immediately. 相似文献
11.
In this sequel to our previous study of the entropic and energetic costs of information erasure [N.G. Anderson, Phys. Lett. A 372 (2008) 5552], we consider direct overwriting of classical information encoded in a quantum-mechanical memory system interacting with a heat bath. Lower bounds on physical costs of overwriting – in both “single-shot” and “sequential” overwriting scenarios – are obtained from globally unitary quantum dynamics and entropic inequalities alone, all within a referential approach that grounds information content in correlations between physical system states. A heterogeneous environment model, required for consistent treatment of sequential overwriting, is introduced and used to establish and relate bounds for various cases. 相似文献
12.
The present paper, based on the information theory of Shannon, studies the holographic information content, its reconstruction, and the compression of the hologram. Starting with the human binocular vision theory, it elaborates not only the information contents of the 3D object and its hologram, but also their relationship in the visual space. By proposing the particular computing method for the holographic information content and achieving meaningful results therefore, it offers the theoretical cornerstone and practical way to the reduction and compression of the holographic information content. 相似文献
13.
During the last decade, great advances have been made
concerning the construction and manipulation of nanostructures. As
a consequence, nanometer stability and control of the sample
position have became crucial points. For this purpose, we have
built an optical microscope with high mechanic stability and we
have implemented a feedback system in order to compensate thermal
drifts. We demonstrate the system stability to be within one
nanometer, with a control on the sample position of some
micrometers, along the three spatial directions. The sample can be
manipulated optically by means of a multiple optical tweezers
setup and its displacements measured with a 3D position detector.
We discuss and characterize the system properties thoroughly. We
finally test the apparatus on a bio-molecular system constituted
by a single myosin motor interacting with an actin filament. 相似文献
14.
Ronald N. Kostoff Jesse A. Stump Dustin Johnson James S. Murday Clifford G.Y. Lau William M. Tolles 《Journal of nanoparticle research》2006,8(3-4):301-321
Text mining is the extraction of useful information from large volumes of text. A text mining analysis of the global open nanotechnology literature was performed. Records from the Science Citation Index (SCI)/Social SCI were analyzed to provide the infrastructure of the global nanotechnology literature (prolific authors/journals/institutions/countries, most cited authors/papers/journals) and the thematic structure (taxonomy) of the global nanotechnology literature, from a science perspective. Records from the Engineering Compendex (EC) were analyzed to provide a taxonomy from a technology perspective.
- The Far Eastern countries have expanded nanotechnology publication output dramatically in the past decade.
- The Peoples Republic of China ranks second to the USA (2004 results) in nanotechnology papers published in the SCI, and has increased its nanotechnology publication output by a factor of 21 in a decade.
- Of the six most prolific (publications) nanotechnology countries, the three from the Western group (USA, Germany, France) have about eight percent more nanotechnology publications (for 2004) than the three from the Far Eastern group (China, Japan, South Korea).
- While most of the high nanotechnology publication-producing countries are also high nanotechnology patent producers in the US Patent Office (as of 2003), China is a major exception. China ranks 20th as a nanotechnology patent-producing country in the US Patent Office.
15.
Cheng-Jun ZhangAn Zeng 《Physica A》2012,391(4):1822-1830
Understanding the structure and evolution of web-based user-item bipartite networks is an important task since they play a fundamental role in online information filtering. In this paper, we focus on investigating the patterns of online users’ behavior and the effect on recommendation process. Empirical analysis on the e-commercial systems show that users’ taste preferences are heterogeneous in general but their interests for niche items are highly clustered. Additionally, recommendation processes are investigated on both the real networks and the reshuffled networks in which real users’ behavior patterns can be gradually destroyed. We find that the performance of personalized recommendation methods is strongly related to the real network structure. Detailed study on each item shows that most hot items are accurately recommended and their recommendation accuracy is robust to the reshuffling process. However, the accuracy for niche items is relatively low and drops significantly after removing users’ behavior patterns. Our work is also meaningful in practical sense since it reveals an effective direction to improve the accuracy and the robustness of the existing recommender systems. 相似文献
16.
Xin Li Daning Hu Yan Dang Hsinchun Chen Mihail C. Roco Catherine A. Larson Joyce Chan 《Journal of nanoparticle research》2009,11(3):529-552
Nanotechnology research has experienced rapid growth in recent years. Advances in information technology enable efficient
investigation of publications, their contents, and relationships for large sets of nanotechnology-related documents in order
to assess the status of the field. This paper presents the development of a new knowledge mapping system, called Nano Mapper
(), which integrates the analysis of nanotechnology patents and research grants into a Web-based platform. The Nano Mapper
system currently contains nanotechnology-related patents for 1976–2006 from the United States Patent and Trademark Office
(USPTO), European Patent Office (EPO), and Japan Patent Office (JPO), as well as grant documents from the U.S. National Science
Foundation (NSF) for the same time period. The system provides complex search functionalities, and makes available a set of
analysis and visualization tools (statistics, trend graphs, citation networks, and content maps) that can be applied to different
levels of analytical units (countries, institutions, technical fields) and for different time intervals. The paper shows important
nanotechnology patenting activities at USPTO for 2005–2006 identified through the Nano Mapper system. 相似文献
17.
In this article, we present an overview of the research activity undertaken in Pakistan in the field of nanoscience and technology
for the period 2001–2010. Starting with almost insignificant publications in this field in 2001, the number has risen steadily
to 430 in 2010. A break up of organizations actively involved in research in this field suggests that most of these publications
have emanated from universities. The contribution of R&D organizations that far outnumber the universities is about 10 percent
of the total. Reasons for the increasing trend in publications, especially in the universities are discussed. 相似文献
18.
Mihail C. Roco Barbara Harthorn David Guston Philip Shapira 《Journal of nanoparticle research》2011,13(9):3557-3590
Governance of nanotechnology is essential for realizing economic growth and other societal benefits of the new technology,
protecting public health and environment, and supporting global collaboration and progress. The article outlines governance
principles and methods specific for this emerging field. Advances in the last 10 years, the current status and a vision for
the next decade are presented based on an international study with input from over 35 countries. 相似文献
19.
M. A. Idris Z. A. Z. Jamal S. B. Jamaludin N. Nafarizal A. K. Othman M. Z. Sahdan M. P. Zakaria M. Ionescu J. Nowotny 《Ionics》2014,20(4):581-592
The present work considers the application of oxide semiconductors in the conversion of solar energy into the chemical energy required for water purification (removal of microbial cells and toxic organic compounds from water) and the generation of solar hydrogen fuel by photoelectrochemical water splitting. The first part of this work considers the concept of solar energy conversion by oxide semiconductors and the key performance-related properties, including electronic structure, charge transport, flat band potential and surface properties, which are responsible to the reactivity and photoreactivity of oxides with water. The performance of oxide systems for solar energy conversion is briefly considered in terms of an electronic factor. The progress of research in the formation of systems with high performance is considered in terms of specific aspects of nanotechnology, leading to the formation of systems with high performance. The nanotechnology approach in the development of high-performance photocatalysts is considered in terms of the effect of surface energy associated with the formation of nanostructured system on the formation of surface structures that exhibit outstanding properties. The unresolved problems that should be tackled in better understanding of the effect of nanostructures on properties and performance of oxide semiconductors in solar energy conversion are discussed. This part is summarised by a list of unresolved problems of crucial importance in the formation of systems with enhanced performance. This work also formulates the questions that must be addressed in order to overcome the hurdles in the formation of oxide semiconductors with high performance in water purification and the generation of solar fuel. The research strategy in the development of oxide systems with high performance, including photocatalysts for solar water purification and photoelectrodes for photoelectrochemical water splitting, is considered. The considerations are focused on the systems based on titanium dioxide of different defect disorder as well as its solid solutions and composites. 相似文献