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1.
Flexible integration of distributed design and manufacturing activities is one of the key issues in applying just-in-time principles along the logistics chain. The potential of AI based approaches in this field is clear, but the inherent asynchrony, concurrency, and inconsistency of distributed operations has reduced enthusiasm so far.This paper discusses coordination in the context of geographically distributed manufacturing of one-of-a-kind products. Cooperation of partners is based on semi-automated user agents which operate as an integrative layer between more dedicated tools and systems. The management of order changes in elevator manufacture is used as a case example.The work reported here is part of the DIMUN project (DIMUN, 1989) in the RACE program.  相似文献   
2.
Summary Volatile carbonyl compounds of carrot varietyFeonia Hunderup S-64 at various stages of maturity were analysed as their 2,4-DNPH's by a combined TLC-GLC-MS method. Twenty-three different carbonyl compounds were identified, of which undecanal, buten-2-al, methylbutenal, pentan-2-one, 6-methyl-5-hepten-2-one and 5-methylfurfural have not previously been found in carrot. During maturation the content of acetaldehyde and acetone increased significantly, while that of methylbutenal decreased.
Die leichtflüchtigen Monocarbonylverbindungen der Karotten in verschiedenen Stufen der Reife
Zusammenfassung Die leichtflüchtigen Carbonylverbindungen der Karotten Varietät Feonia Hunderup S-64 wurden in verschiedenen Stufen der Reife als 2,4-DNPH mit der kombinierten DC-GC-MS-Methode analysiert. Dreiundzwanzig verschiedene Carbonylverbindungen wurden nachgewiesen. Von diesen sind Undecanal, 2-Butenal, Methylbutenal, 2-Pentanon, 6-Methyl-5-hepten-2-on und 5-Methylfurfural noch nicht in Karotten aufgefunden worden. Während des Reifens nahm der Gehalt an Acetaldehyd und Aceton bedeutend zu. Der Gehalt an Methylbutenal verminderte sich.
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3.
The classical plate method for discriminating between viable and nonviable yeast cells in stored baker's yeast was compared with dead cell staining techniques using methylene blue and three fluorochrome stains. The increase of dead yeast cells during storage of baker's yeast for up to 16 days at 5°C, 20°C and 35°C was determined. During prolonged storage, especially at 35°C, the death rate increased rapidly and the yeast cake began to soften because of autolysis. In these conditions the choice of method for determining the proportion of dead cells proved to be of great importance. Useful results for yeast stored for some time at 35°C could be obtained only by the fluorochrome technique using primuline, acridine orange or acriflavine as fluorochromes.  相似文献   
4.
We develop and describe a framework for research in a particular segment of digital advertising. Internet Advertising Paid Slots and Spaces (IAPS) is a neologism and work almost like a stock exchange for buying and selling advertising in various formats on designated spaces around web and make a significant contribution to Internet advertising revenues. These paid spaces were found to encompass diverse areas of Internet advertising that include search engine marketing, social media advertising and display advertising. Given the complexity of the modern digital advertising eco system, this literature review seeks to provide clarity, up-to-date knowledge and ongoing insights into Internet advertising channels, for managers making investment decisions in this context.  相似文献   
5.
The impact of information and communications technology (ICT) in tourism (e-tourism) has altered the ways tourism services are accessed and consumed. Ubiquitous and highly innovative ICTs provide different channels for consumers to use tourism services; thus, studies on e-tourism are numerous and fragmented. Different factors account for how consumers embrace these channels. The purpose of this study is to review studies on consumers’ acceptance or adoption of e-tourism in order to group the studies, synthesize the theories, models and frameworks used and identify the antecedents influencing consumers’ e-tourism acceptance and usage. A total of 71 studies from 2005 to 2016 (inclusive) from both tourism-based and non-tourism-based journals were selected, synthesized, and included. Based on their contexts, similarity and relevance, the 71 studies were segregated into three distinct groups. This study found that research among the groups is uneven. Implications and research directions are suggested.  相似文献   
6.
7.
Addition of Tween 80 to the growth medium of baker's yeast (Saccharomyces cerevisiae) under anaerobic conditions resulted in an increased content of 9-cis-octadecenoic acid (oleic acid) in a membrane preparation consisting mainly of plasma membrane. There was no significant effect on the pyruvate decarboxylation capacity of disintegrated cells, but that of intact cells was significantly enhanced, presumably because of an oleate-induced increase in the permeability of the plasma membrane to pyruvate.  相似文献   
8.
MEMS助力推动下一代无线通信   总被引:1,自引:0,他引:1  
未来的无线通信系统将具备各种新功能并高度微型化。而且,3代和4代多模/多波段无线终端设备将为新业务、互联网与Mcommerce(移动电子商务)数据、以及静态/视频图象提供网络连接。此外,终端设备也应具备更多新功能来吸引更多终端用户。微电子 机械(microelectromechanical,MEM)元件与系统可提高创新性3代产品的集成化水平,并可调整器件的特性和工作方式,因此可降低3代 图 产品的尺寸和成本。它们还将为    无线系统带来新的体系结构和功耗管理特征。此外,MEMS还将推动新功能、传感器、执行器在无线终端设备上的集成。用户接口需要采用新的技术解决方案。微机械传感器和麦克风已经有元件形式的产品,它们可以被看作是更复杂、包括若干集成化传感器元件的智能系统的一个组成部分。对移动终端来说,娱乐和游戏功能是新功能开发的重要推动力,传感器和执行器也是如此。微反射镜和微透镜为照相机和显示器的实现带来了新的可能,如投影显示。因此MEMS将极大地促进未来无线系统的发展。本文将对 MEMS 在无线通信发展 中的应用进行探讨,首先讨论微系统 化、多功能器件在紧凑系统中的集成、...  相似文献   
9.

Wireless connectivity has become a significant part of human life all over the world, both in developing and developed countries. In order to provide sufficient coverage without the densification of cellular networks, relatively low carrier frequencies should be used. This paper considers the reuse of the digital terrestrial television (DTT) band for cellular system operation in Kenya, while protecting incumbent TV signal reception according to the Dynamic Spectrum Alliance (DSAL) rules. A state of the art model for DTT coverage and allowed cellular system power calculation is tested using real data for Kenya. Suggestions regarding future DSAL rules amendments are provided. Moreover, the amount of spectrum resources available for cellular system operation in the DTT band in Kenya is estimated against varying system parameters.

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10.
BACKGROUND: Sugars, acids and vitamin C are essential components influencing the sensory and nutritional properties of currants (Ribes sp.). In this study the effects of growth latitude and weather conditions on these components in red, white and green currant cultivars were systematically investigated for the first time. RESULTS: Red Dutch (a red Ribes rubrum cultivar) contained more malic acid but fewer sugars and had a lower sugar/acid ratio than Vertti (a green Ribes nigrum cultivar) and White Dutch (a white R. rubrum cultivar). Fructose (27–56 g L?1 juice) and glucose (21–54 g L?1) were the major sugars in all currant samples, but sucrose (7–20 g L?1) was present only in Vertti. Vertti contained the most ascorbic acid. Sugars, malic acid and the sugar/acid ratio in Red Dutch were 11–28% higher in southern Finland than in northern Finland. The corresponding values in Vertti were 6–16% lower in the south than in the north, but no differences were found in White Dutch. As the relative humidity decreased, the amounts of citric acid and total acid increased in all cultivars, while the amount of sugars increased in Vertti but decreased in White Dutch and Red Dutch. In Red Dutch, high temperature and radiation levels increased the sugar content. CONCLUSION: The influence of latitude and weather conditions on qualitative parameters of currants varies with the cultivar. This study provides important guidance for currant cultivation and for further physiological and enzymological studies. Copyright © 2009 Society of Chemical Industry  相似文献   
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