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1.
The opening for the Australian Garden was jointly held by the BHP Billiton China and the CAS South China Botanical Garden (SCBG) in Guangzhou, capital of south China's Guangdong Province on 18 January. Those present at the ceremony included Prof. Andrew Smith and Prof. Sue Serjeantson from the Australian Academy of Science, Prof. Dave Paterson from the Royal Botanic Garden in Edinburgh, and representatives from the CAS Headquarters, CAS Guangzhou Branch, PHB Billiton China and SCBG.  相似文献   

2.
An agreement for protecting the forest tree germplasm resources was recently signed by the CAS Kunming Institute of Botany (KIB) and the World Agro-forestry Center (ICRAF) in Kunming, capital of southwest China's Yunnan Province.  相似文献   

3.
Although often downplayed and instrumental, there is evidence that communication in projects is essential in achieving value creation. Our main interest in this paper is on temporary continuity, a situation where the temporary becomes a permanent condition in social systems. The question that we have address is: What characterizes project communication in a situation with temporary continuity?We argue for the need to transform communication processes into communication capabilities. In a situation with temporary continuity, there is a need to connect to a large number of value-creating processes, and communicating capabilities need to be a part of a communication system, where the aim is to bind together value-creating processes and communication capabilities. We construct a viable system consisting of five sub-systems. To become a viable system, projects in the form of temporary continuity, must handle the potential conflict between a culture of performance and a culture of innovation. This involves developing social mechanisms for coordination and interaction, with a focus on developing communication capabilities, in parallel with focusing on all of the five value-creation processes.  相似文献   

4.
When the need to record and track the point of view of different actors in organizational processes becomes a key point for decision makers, a common representation of knowledge from different perspectives and a map of the situation and the decision and action needs could be useful. A methodology that easily and transparently integrates different ‘soft’ and ‘hard’ tools in a common knowledge structuring approach is proposed to deal with complexities and uncertainties in a socio-technical contest. The purpose of this paper is to show the potentialities of this methodology in a real case, in terms of organizational knowledge acquisition and structuring in a multi-actor public context, a university faculty, in relation to a radical change.  相似文献   

5.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood.  相似文献   

6.
1961年~2004年东北地区四季降水的时空演变特征   总被引:7,自引:1,他引:6  
利用Anusplin插值软件对东北地区146站1961年~2004年四季降水量进行空间化处理,各季区域平均MRE分别为春季14.3%、夏季14.1%;秋季18.1%;冬季25.1%。对栅格数据采用空间分析和时间序列分析相结合的方法进行四季降水时空演变特征分析,结果表明:从时间上看,春季,整个时段呈弱增多趋势,但不显著,1980年代前增加,之后减少;夏季呈减少趋势,1985以后呈显著减少趋势;秋季整个时段呈弱的减少趋势,1990年代开始显著减少,2000年以后略有增加;冬季年代际变化特征明显,呈波动增多趋势,近10年增幅较大。从空间分布上看,春季,黑龙江北部和东部部分地区、吉林东部降水显著增多,增幅为(3~9)mm/10年,辽宁中部部分地区降水显著减少,减幅为(3~7)mm/10年。夏季,东北大部地区降水以减少为主,黑龙江中部和辽东半岛地区显著减少,减幅为(20~40)mm/10年。秋季,东北大部地区降水减少,黑龙江东部局部、吉林中部和南部部分地区显著减少,减幅为(6~10)mm/10年。冬季,黑龙江大部、吉林大部降水显著增多,增幅为(1~3)mm/10年,辽宁南部和西部部分地区显著减少,减幅为(1~2)mm/10年。  相似文献   

7.
This paper is concerned with techniques for fuzzy query processing in a database system. By a fuzzy query we mean a query which uses imprecise or fuzzy predicates (e.g. AGE = “VERY YOUNG”, SALARY = “MORE OR LESS HIGH”, YEAR-OF-EMPLOYMENT = “RECENT”, SALARY ? 20,000, etc.). As a basis for fuzzy query processing, a fuzzy retrieval system based on the theory of fuzzy sets and linguistic variables is introduced. In our system model, the first step in processing fuzzy queries consists of assigning meaning to fuzzy terms (linguistic values), of a term-set, used for the formulation of a query. The meaning of a fuzzy term is defined as a fuzzy set in a universe of discourse which contains the numerical values of a domain of a relation in the system database.The fuzzy retrieval system developed is a high level model for the techniques which may be used in a database system. The feasibility of implementing such techniques in a real environment is studied. Specifically, within this context, techniques for processing simple fuzzy queries expressed in the relational query language SEQUEL are introduced.  相似文献   

8.
Microfluidic blood plasma separation via bulk electrohydrodynamic flows   总被引:1,自引:0,他引:1  
An effective mechanism for rapid and efficient microfluidic particle trapping and concentration is proposed without requiring any mechanically moving parts. When a voltage beyond the threshold atmospheric ionization value is applied on a sharp electrode tip mounted at an angle above a microfluidic liquid chamber, the bulk electrohydrodynamic air thrust that is generated results in interfacial shear and, hence, primary azimuthal liquid surface recirculation. This discharge driven vortex mechanism, in turn, causes a secondary bulk meridional liquid recirculation, which produces an inward radial force near the bottom of the chamber. Particles suspended in the liquid are then rapidly convected by the bulk recirculation toward the bottom, where the inward radial force causes them to spiral in a helical swirl-like fashion toward a stagnation point. In particular, we show that these flows, similar to Batchelor flows occurring in a cylindrical liquid column between a stationary and rotating disk, can be used for the separation of red blood cells from blood plasma in a miniaturized device.  相似文献   

9.
The study presents and synthesizes the results of a series of five experiments on human information-seeking behavior in three different information-seeking environments. The first three experiments utilized a highly-controlled, simulated information-seeking task developed to study human search strategies in citation networks. Emphasis in the fourth and fifth experiments was placed on assessing the value of information for humans in realistic search environments. Subjects search on a topic of their own choice in a data base of fiction in Experiment Four and a data base of technical literature in Experiment Five. After summarizing the experimental results, a conceptual model of how humans value information is presented. The model is then used as a basis for a broad interpretation of the empirical results. Implications of both the empirical and modeling results are considered for the areas of information retrieval logic, system flexibility, retrieval methods, types of aiding, online estimation of information value, and computerizing versus computer-aiding.  相似文献   

10.
图书馆智慧服务的概念、内涵与分析   总被引:1,自引:0,他引:1  
张延贤  王梅 《现代情报》2013,33(4):34-38
智慧是图书馆存在与发展的一个非常重要的现象与属性,图书馆智慧,简而言之就是图书馆人在图书馆的历史与当代的实践中,对图书馆现象的认识、理解和把握,是从图书馆实践中抽取,高于图书馆实践又应用于图书馆实践的一种图书馆人的能力与素质的综合体现。图书馆智慧服务是图书馆人对读者工作的一种积极进取的自主选择,是图书馆在信息化时代读者服务的一种或多种新理念、新能力与新服务方式。图书馆智慧服务主要有智能性的图书馆智慧服务、知识性的图书馆智慧服务和理念性的图书馆智慧服务等3种概念及内涵。智能性的图书馆智慧服务实质上是图书馆的一种技术智慧,知识性的图书馆智慧服务实质上是图书馆的一种学问智慧,而理念性的图书馆智慧服务实质上是图书馆的一种人文智慧。  相似文献   

11.
气候变化和人类活动对湟水河流域径流量影响的定量评估   总被引:7,自引:0,他引:7  
湟水河是西北干旱区重要河流之一,对维持西北干旱区生态平衡具有极其重要的作用。近年来,湟水河流域水资源减少已经引起了严重的生态环境问题,本文根据流域内1966-2010年水文气象数据,采用累积距平法、累积量斜率变化率法,对湟水河流域径流量和气候变化特征及趋势进行了分析,并定量评估了气候变化和人类活动对径流量变化的影响。结果表明:年降水量、蒸散发量和径流量总体均呈减少趋势;径流量的下降变幅为0.1亿m3/10a,具有4a、9a和20a的准周期变化,且在1987年前后发生了突变;气候变化对湟水河流域径流减少的贡献率达35.46%,人类活动改变了部分水循环的路径,对径流的减少起主导作用,贡献率为64.54%。  相似文献   

12.
世界上很多著名大学,因为某一学科处于领先位置而名扬天下。很多大学因为培育出著名科学家、政治家、经济学家而闻名于世。这些大学最显著的特点是,有独到的办学特色,在某一教学领域处于世界顶级水平。培育特色专业,就是把学校的某一学科、某一专业打造成为国内乃至国际顶级的学科和专业,为社会培养出更多实用型人才,这是实现职业技术教育长足发展的重要途径。  相似文献   

13.
Particle focusing is an essential step in a wide range of applications such as cell counting and sorting. Recently, viscoelastic particle focusing, which exploits the spatially non-uniform viscoelastic properties of a polymer solution under Poiseuille flow, has attracted much attention because the particles are focused along the channel centerline without any external force. Lateral particle migration in polymer solutions in square channels has been studied due to its practical importance in lab-on-a-chip applications. However, there are still many questions about how the rheological properties of the medium alter the equilibrium particle positions and about the flow rate ranges for particle focusing. In this study, we investigated lateral particle migration in a viscoelastic flow of DNA solution in a square microchannel. The elastic property is relevant due to the long relaxation time of a DNA molecule, even when the DNA concentration is extremely low. Further, the shear viscosity of the solution is essentially constant irrespective of shear rate. Our current results demonstrate that the particles migrate toward the channel centerline and the four corners of a square channel in the dilute DNA solution when the inertia is negligible (elasticity-dominant flow). As the flow rate increases, the multiple equilibrium particle positions are reduced to a single file along the channel centerline, due to the elasto-inertial particle focusing mechanism. The current results support that elasto-inertial particle focusing mechanism is a universal phenomenon in a viscoelastic fluid with constant shear viscosity (Boger fluid). Also, the effective flow rate ranges for three-dimensional particle focusing in the DNA solution were significantly higher and wider than those for the previous synthetic polymer solution case, which facilitates high throughput analysis of particulate systems. In addition, we demonstrated that the DNA solution can be applied to focus a wide range of particle sizes in a single channel and also align red blood cells without any significant deformation.  相似文献   

14.
Adelman J 《Endeavour》2007,31(3):94-98
Discovered in the nineteenth century by the Canadian Geological Survey, the Eozo?n canadense fossil, or 'dawn animal of Canada', created a sensation in the geological community. Only a few initially challenged its status as a fossil organism, including two professors in the remote Irish town of Galway. These men claimed that Eozo?n was nothing more than a mineral formation and did not represent the discovery of the primordial organism. Supporters of Eozo?n closed ranks and a heated debate soon broke out in a range of periodicals. The story of Eozo?n lays bare the construction of scientific credibility, a process that was threatened in the second half of the nineteenth century by the proliferation of popular science.  相似文献   

15.
An impressive literature documents how individual-level factors correlate with entrepreneurship and commercialization behaviors. We have far less insight, however, into how different organizational contexts may, in fact, play a dominant role in shaping these individuals and their behaviors. In this paper, I leverage a unique case of commercialization in which a largely overlapping team attempted to commercialize a technology in two different organizational contexts – first, in a university and later in a startup firm. By detailing the contextual features in each organizational environment and by linking these features to the participants’ differing approaches and attitudes toward commercialization, I extend the current literature through a demonstration of how organizational context shapes not only the initial decision to become an entrepreneur, but also the specific ways in which individuals interpret and act upon an entrepreneurial mission. More generally, I contribute to the literature on the commercialization of university research by highlighting some of the challenges inherent in adapting a context optimized for exploration to the task of exploitation.  相似文献   

16.
This paper applies network analysis to a citation database that combines the key references in the fields of Entrepreneurship (ENT), Innovation Studies (INN) and Science and Technology Studies (STS). We find that citations between the three fields are relatively scarce, as compared to citations within the fields. As a result of this tendency, a cluster analysis of the publications in the database yields a partition that is largely the same as the a priori division into the three fields. We take this as evidence that the three fields, although they share research topics and themes, have developed largely on their own and in relative isolation from one another. We also apply a so-called ‘main path’ analysis aimed at outlining the main research trajectories in the field. Here we find important differences between the fields. In STS, we find a cumulative trajectory that develops in a more or less linear fashion over time. In INN, we find a major shift of attention in the main trajectory, from macroeconomic issues to business-oriented research. ENT develops relatively late, and shows a trajectory that is still in its infancy.  相似文献   

17.
Reading together draws much attention as a societal concern for children not only to yield emotional reaction but also to gradually advance intellectual thinking. We here aim to build a new environment, in which children’s browsing and reading of picture books together with families and/or friends is steadily enhanced, by installing the BrowsReader in the children’s room of a public library or a kindergarten. The original BrowsReader was a system to assist children in finding and reading picture books. The children, by gathering around the BrowsReader, can browse picture books and then choose and read a book by flipping pages on it. After reproducing each printed, digitized or web picture book as a surrogate picture book consisting of the front-cover image followed by the page images, we first introduce two basic notions: (i) an abstracted bookshelf, which presents the front-cover images of the surrogate picture books in the form where all are linearly arranged, with some of the images bundled in places, and (ii) a unified view, which presents each page of any surrogate picture book in a form that seems like a printed picture book’s page. We then specify, based on these notions, the improved version of the BrowsReader which can be installed in each children’s room so that children together with families and/or friends can easily browse a large number of surrogate picture books as if they are browsing in the physical bookshelves of the children’s room, and can read a wide variety of surrogate picture books as if they are reading ordinary printed picture books on a table. The improvement was carried out in a step by step process based on feedback and results from case studies, and its effects were clarified by seeing whether, in a new environment, the children’s activity in browsing/reading together were steadily enhanced when using the BrowsReader.  相似文献   

18.
In this paper, a robust self-triggered model predictive control (MPC) scheme is proposed for linear discrete-time systems subject to additive disturbances, state and control constraints. To reduce the amount of computation on controller sides, MPC optimization problems are only solved at certain sampling instants which are determined by a novel self-triggering mechanism. The main idea of the self-triggering mechanism is to choose inter-sampling times by guaranteeing a fast decrease in optimal costs. It implies a fast convergence of system states to a compact set where it is ultimately bounded and a reduction of computation times to stabilize the system. Once the state enters a terminal region, the system can be stabilized to a robust invariant set by a state feedback controller. Robust constraint satisfaction is ensured by utilizing the worst-case set-valued predictions of future states in such a way that recursive feasibility is guaranteed for all possible realisations of disturbances. In the case where a priority is given to reducing communication costs rather than improvement in control performance in a neighborhood of the origin, a feedback control law based on nominal state predictions is designed in the terminal region to avoid frequent feedback. Performances of the closed-loop system are demonstrated by a simulation example.  相似文献   

19.
This paper describes a real-time investigation of the total new product portfolios of nine product departments in the scientific instrument industry. It was found that within these portfolios only a few new products represented a major advance in functional performance. Most new products offered only incremental performance improvement, and many ‘new’ products were direct copies of competitors ' offerings.The scientific instrument innovation process is described in seven stages: recognition of need, invention of solution, prototype development, use in application, precommercial information dissemination, product engineering, and commercialization. In those cases where users were involved in the majority of the first five stages of the innovation process, the innovation was either a major functional improvement or a minor improvement that had not been initiated as a direct response to a competitor's product introduction. Direct copies and minor improvements that were competitive responses are notable for the absence of user involvement in the innovation process.Finally, the decision of a manufacturer to commercialize an innovation was unrelated to the level of user activity in the prior stages of the innovation process.  相似文献   

20.
1960年至2007年汾河流域气温年际和季节性变化特征分析   总被引:7,自引:3,他引:4  
刘宇峰  孙虎  原志华 《资源科学》2011,33(3):489-496
运用线性倾向分析、滑动平均法、Mann-Kendall法等数理分析方法,对山西省汾河流域19个气象站1960年-2007年的逐月气温资料进行了分析。研究表明:自1960年以来,汾河流域年平均气温、平均最高和最低气温均呈波动变化趋势,并有升高趋势,递增率分别为0.32℃/10a、0.13℃/10a和0.50℃/10a。同时,气温年较差呈减小趋势,近48年的气温年较差递减率为0.37℃/10a。此外,年平均气温、平均最高和最低气温发生趋暖突变的时间分别是1993年、1996年、1981年,且近15年是流域年平均气温发生上升的主要时段。气候趋暖还表现出在冬季气温的递增速率最大的特点。流域南北年均气温变化的区域差异并不是很明显,但就各区域的季节变化而言,春冬两季的年均气温变化则表现出明显的区域差异。  相似文献   

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