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1.
Food supply chains are increasingly complex and dynamic due to (i) increasing product proliferation to serve ever diversifying and globalising markets as a form of mass customisation with resulting global flows of raw materials, ingredients and products, and (ii) the need to satisfy changing and variable consumer and governmental demands with respect to food safety, animal welfare, and environmental impact. Transparency in the food supply chain is essential to guarantee food quality and provenance to all users of food and food products. Intensified information exchange and integrated information systems involving all chain actors are needed to achieve transparency with respect to a multitude of food properties.In this paper, specific challenges of food supply chains are highlighted. Major elements are addressed that support transparency to consumers, the government and food companies, which are considered the claimants of transparency. Elements considered to be enablers of transparency are governance mechanisms, quality and safety standards and information exchange. The paper specifies these transparency claimants and enablers for food supply chains and identifies major information system functions and information technology applications needed to comply with transparency demands. It thereby provides a framework for transparency analysis in food supply chains.  相似文献   
2.
采用冲击实验、拉伸实验、超景深三维显微镜、扫描电镜和分光光度计等手段,对PVC/SBS/MBS三元共混体系的冲击强度、拉伸强度、形态结构以及光学透明性等进行了研究。实验结果表明,MBS能有效改善PVC/SBS共混体系的界面相容性。当SBS和MBS的总量不变时,随着MBS相对含量的增加,共混体系的缺口冲击强度逐渐增加,透光率在m(MBS)/m(SBS)=28/80时达到最大值,光学透明性能最好。  相似文献   
3.
3D geological models commonly built to manage natural resources are much affected by uncertainty because most of the subsurface is inaccessible to direct observation. Appropriate ways to intuitively visualize uncertainties are therefore critical to draw appropriate decisions. However, empirical assessments of uncertainty visualization for decision making are currently limited to 2D map data, while most geological entities are either surfaces embedded in a 3D space or volumes.This paper first reviews a typical example of decision making under uncertainty, where uncertainty visualization methods can actually make a difference. This issue is illustrated on a real Middle East oil and gas reservoir, looking for the optimal location of a new appraisal well. In a second step, we propose a user study that goes beyond traditional 2D map data, using 2.5D pressure data for the purposes of well design. Our experiments study the quality of adjacent versus coincident representations of spatial uncertainty as compared to the presentation of data without uncertainty; the representations' quality is assessed in terms of decision accuracy. Our study was conducted within a group of 123 graduate students specialized in geology.  相似文献   
4.
一种基于内容的可扩展性透明Web Cluster体系结构的设计   总被引:3,自引:1,他引:3  
金亮  陈志刚  张松 《计算机工程》2004,30(7):101-103
主要探讨基于内容的Web Cluster,在分析现有方案不足的基础上提出了一种新的基于内容的可扩展性透明Web Cluster体系结构。叙述了其工作机理及所采用的技术方案,重点论述了该集群架构的优越性,最后给出了该集群架构在Linux环境下的模拟实现。  相似文献   
5.
A chitosan-based carbon dioxide (CO2) indicator was developed to monitor freshness or quality of packaged foods during their storage, as elevated CO2 levels inside a package is one of the prime indicators of microbial spoilage of food. The objective of this proof-of-concept study, therefore, was to develop a chitosan-based CO2 indicator and to investigate its performance in different operating environments. For the enhancement of signal strength of indicator, 2-amino-2-methyl-1-propanol (AMP) was used as an additive to the chitosan solution. Aqueous chitosan–AMP suspensions were prepared by addition of chitosan (0.1%, 0.2% and 0.4%) and AMP (0%, 5%, 10% and 20%) to distilled water at pH 7.0. Thereafter, the aqueous chitosan suspensions were incubated under 100% and 20% CO2 test atmospheres. The aqueous solubility of chitosan, which in turn impacts the degree of transparency of the suspension, was tested at different pHs and time intervals, spectrometrically. The transparency of 0.2% chitosan aqueous suspension increased dramatically below pH 6.5 under 20% or 100% CO2 incubation. The addition of a 5% AMP concentration to the chitosan suspension was found optimal for maximum CO2 absorption and this, therefore, increased transparency by more than 90%.  相似文献   
6.
Government agencies worldwide continue their commitment to providing open data in order to increase transparency of education, healthcare and other public services. Focusing on open government information systems (IS) that provide performance-related data, this paper explores the ongoing tension between government’s goal of transparency and the resulting largely opaque datification effects. Our research insights are derived from an empirical longitudinal study of a controversial open government IS called My School, currently providing performance data on almost 10,000 schools in Australia. We investigate the tension between transparency intended with schools’ open performance data and datification effects they create within the education system and a broader society, through the theoretical lens of Complex Adaptive Systems (CAS). Our study reveals how the tension emerges due to unpredictable use, propagation and reinterpretation of open data by more and more users. Consequently, the original meaning of data gets distorted, as these users continue to reconstruct and reinterpret ‘data’ in their own contexts and adapt their behavior in pursuit of their strategic goals. We also identify and theorize seven datification patterns underlying the tension and the ways they produce various social consequences. Based on these research contributions we discuss important strategic implications for government decision makers and identify new opportunities for future research on open government IS.  相似文献   
7.
提出了一个含多个脱线TTP的公平的不可否认协议。与以前的不可否认协议相比,其特点是把一个TTP的任务分散到t个TTP,减少了对一个TTP的依赖,还可以检测出不诚实的TTP,并且实现了TTP的透明性。  相似文献   
8.
本文回溯了勒·柯布西耶在纯粹主义运动(1918—1925年)前后,其绘画中空间观念所经历的转向。彼时的让纳雷以绘画作为实验工具,发展了他对于空间的理解。本文把勒·柯布西耶在纯粹主义前后的绘画探索分为四个阶段,通过比较四个阶段的作品,指出勒·柯布西耶的空间观念经历了由注重写实与透视,到关注对象平面中的几何与秩序,再到用透明的块面相互叠加来营造深度感,最后转为对于大自然、人体等有机形式的探索,揭示出其不同绘画题材背后隐藏着的形式逻辑的必然联系。  相似文献   
9.
Abstract

Fully densified Al2O3 ceramics with fine grain size were obtained by pulsed electric current sintering through a two-step heating profile (referred to as TS-PECS). Highly transparent Al2O3 polycrystals with fine grain size (400 nm) were successfully fabricated by the TS-PECS process, namely, sintering at 1000°C for 1 h and followed at 1200°C for 20 min under uniaxial pressure of 100 MPa. Effects of the first step temperature and heating rate were discussed for bulk density, grain size and transparency. The temperature in the first step strongly affects densification and grain growth of Al2O3. On the other hand, heating rate, even of 100 K min?1, in TS-PECS does not give significant influences on densification and grain growth of Al2O3. Inline transmittance at 640 nm in wavelength normalised to 1 mm in thickness is increased by decreasing heating rate even in TS-PECS.  相似文献   
10.
半导体光放大器以其良好的非线性在全光网络中具有广泛应用,但较长的载流子恢复时间一直是制约其用于超快全光信号处理的速率瓶颈,基于包含自发辐射噪声的半导体光放大器模型,探讨了提高半导体光放大器增益恢复时间的有效途径,通过对制约透明波长移动,增益饱和与有效载流子寿命的相关因素进行数值分析,得出以下结论:与单辅助光相比,采用双辅助光可以在不牺牲信号增益的前提下进一步缩短载流子寿命,因而是提高半导体光放大器增益恢复时间的有效途径,这一点对工程设计和应用具有一定的指导意义.  相似文献   
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