Assessing Framing of Uncertainties in Water Management Practice

Dealing with uncertainties in water management is an important issue and is one which will only increase in light of global changes, particularly climate change. So far, uncertainties in water management have mostly been assessed from a scientific point of view, and in quantitative terms. In this paper, we focus on the perspectives from water management practice, adopting a qualitative approach. We consider it important to know how uncertainties are framed in water management practice in order to develop practice relevant strategies for dealing with uncertainties. Framing refers to how people make sense of the world. With the aim of identifying what are important parameters for the framing of uncertainties in water management practice, in this paper we analyze uncertainty situations described by decision-makers in water management. The analysis builds on a series of “Uncertainty Dialogues” carried out within the NeWater project with water managers in the Rhine, Elbe and Guadiana basins in 2006. During these dialogues, representatives of these river basins were asked what uncertainties they encountered in their professional work life and how they confronted them. Analysing these dialogues we identified several important parameters of how uncertainties get framed. Our assumption is that making framing of uncertainty explicit for water managers will allow for better dealing with the respective uncertainty situations.     

Electric Properties of Contacts t o HTS Thin Films at Current Densities J > J c

The role of superconducting film contacts when transporting critical current density was investigated using d.c. and electric short pulses. It was found that both d.c. and pulse current exceeding critical current I _c dissipate at the film contacts, i.e. at the metal/superconductor planar interface containing an intermediate layer of degraded superconductor. Current I > I _c dissipation at the contacts initiates electric-thermal destruction of the superconducting film cathode. The resulting damage to the film is explained in terms of the formation of a (p/i/n) junction at the normal-metal(n)/mixed-state super-conductor(p) interface containing (i) layer of low electric conductivity.     

未来城市广告发展趋势综合思考

对未来城市广告活动发展的前景进行了探索，归纳为几个主要的发展方向：广告是城市形象系统建立与推广的主要力量，网络广告必将成为未来广告的主要媒体形式；城市广告发展必须建立在行业规范的基础上；面向未来，实施可持续发展战略才是长远之计，同时，对中国广告业的现状，任务及其前景做了相应的剖析和展望。     

礼觉设计中的数码技术

新到来的数字时代给视觉艺术领域带来了技术上的支持和创新,通过阐述数码技术在电影的特技场景制作中、广告的特殊镜头合成中以及纯艺术思维中的表现来论述新兴的数码技术给视觉艺术带来的重大变革和意义。     

中国媒介产业链解析

在第二次现代化的理论框架内,结合我国产业结构的状况分析了我国媒介产业在整个产业链上的相对位置;提出了我国媒介产业要在未来近50年的时间内赶上那些已经进入第二次现代化的发达国家的媒介产业。必须借鉴其媒介产业发展过程中的经验,优化产业结构,使媒介产业结构不断合理化和高度化,将媒介产业作为文化中的主导产业,带动相关产业的发展,形成一个合理的媒介产业链,规避风险,实现媒介的跨越式发展。     

运算放大器电路固有噪声的分析与测量

三运放仪表放大器的介绍仪表放大器（INA）对小差动信号进行了放大。大多数INA都包括若干个电阻和运算放大器（op amps）。虽然可以使用分立组件来构建这些INA,但是使用单片集成电路INA的优点颇多。使用分立组件很难达到单片INA的精度和尺寸。     

生物组织中强度调制的连续激光激发的光声信号影响因素研究

分析了强度调制的连续激光激发的光声信号形成过程以及调制脉宽对光声信号强度的影响,发现随着调制方波脉宽的增加,生物组织吸收的光功率增加,光声信号幅值增加。研究了调制脉宽对光声成像技术轴向分辨率的影响,发现随着调制方波脉宽宽度的增加,光声信号的脉宽增加,其轴向分辨率变差。在理论研究的基础上进行了实验验证,通过方波调制的激光二极管的出射激光激发生物组织获取声信号。在激光二极管出射光功率提高受限的条件下,通过增加作用在生物组织上的光功率密度获取高分辨率、高信噪比的光声图像。对强度调制连续激光激发的光声成像技术的研究能够为光声成像技术提供一种低成本、便携式的设备,为进一步研究提供参考。     

Effect of Nanoparticles on Electron and Thermoelectric Transport

Recent experimental results have shown that adding nanoparticles inside a bulk material can enhance the thermoelectric performance by reducing the thermal conductivity and increasing the Seebeck coefficient. In this paper we investigate electron scattering from nanoparticles using different models. We compare the results of the Born approximation to that of the partial-wave method for a single nanoparticle scattering. The partial-wave method is more accurate for particle sizes in the 1 nm to 5 nm range where the point scattering approximation is not valid. The two methods can have different predictions for the thermoelectric properties such as the electrical conductivity and the Seebeck coefficient. To include a random distribution of nanoparticles, we consider an effective medium for the electron scattering using the coherent potential approximation. We compare various theoretical results with the experimental data obtained with ErAs nanoparticles in an InGaAlAs matrix. Reasonably good agreement is found between the measured and theoretical electrical conductivity and Seebeck data in the 300 K to 850 K temperature range.     

Multinomial Sampling of Latent Variables for Hierarchical Change-Point Detection

Bayesian change-point detection, with latent variable models, allows to perform segmentation of high-dimensional time-series with heterogeneous statistical nature. We assume that change-points lie on a lower-dimensional manifold where we aim to infer a discrete representation via subsets of latent variables. For this particular model, full inference is computationally unfeasible and pseudo-observations based on point-estimates of latent variables are used instead. However, if their estimation is not certain enough, change-point detection gets affected. To circumvent this problem, we propose a multinomial sampling methodology that improves the detection rate and reduces the delay while keeping complexity stable and inference analytically tractable. Our experiments show results that outperform the baseline method and we also provide an example oriented to a human behavioral study.

     

Modified-atmosphere packaging of minimally processed “Lollo Rosso” (Lactuca sativa) Phenolic metabolites and quality changes

 The effect of modified-atmosphere packaging (MAP) on the amount of soluble phenolics in, and the visual appearance of, white, green and red tissues of minimally processed “Lollo Rosso” lettuce were evaluated. Minimal processing induced a two-fold increase in the amount of soluble phenylpropanoids in the midribs during storage in air at 5°C. When the lettuce was stored in the presence of 2–3% O₂ and 12–14% CO₂, this increase was not induced and no browning was observed. A particularly marked decrease in the amount of phenylpropanoids was observed in MAP-stored green and red tissues. The concentrations of flavonoids and anthocyanins did not change much in midribs and green tissues, while they were significantly degraded in red tissues under MAP conditions. MAP storage proved useful in the prevention of browning, the main cause of quality loss in minimally processed “Lollo Rosso” lettuce. However, MAP storage was not so beneficial for the preservation of the quality of red tissues and, in fact, their overall visual quality, texture, aroma and macroscopic breakdown under MAP conditions were worse than those of air-stored tissues. Received: 5 November 1997