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91.
Ber e 1, a major allergen from Brazil nuts, is very stable to in vitro peptic digestion. As heat-induced denaturation may affect protein digestibility, the denaturation behaviour of Ber e 1 was investigated. The denaturation temperature of Ber e 1 varies from approximately 80–110 °C, depending on the pH. Upon heating above its denaturation temperature at pH 7.0, the protein partly forms insoluble aggregates and partly dissociates into its polypeptides, whereas heating at pH 5.0 does neither induce aggregation, nor dissociation of the protein. The denaturation temperature of approximately 110 °C at pH values corresponding to the general pH values of foods (pH 5–7) is very high and is expected to be even higher in Brazil nuts themselves. As a result, it is unlikely that heat processing causes the denaturation of all Ber e 1 present in food products. Consequently, the allergen is assumed to be consumed (mainly) in its native form, having a high stability towards pepsin digestion.  相似文献   
92.
一般认为,气体及液体处理技术已经很成熟,但多来源且更复杂组成的进料气体及更严格的环保要求和产品规格又不断推动着技术的进步。本文介绍了壳牌所开发使用的处理技术及近两年内的一些最新发展。含硫化氢气体处理技术包括传统的液相吸收、固定床吸收、气相的催化转换反应以及生物处理技术。壳牌公司可根据进料气体的情况和最终产品的要求,对整个工艺整合,并给出最优化的解决方案,以达到更环保,可靠性更高且更节省投资的目的。  相似文献   
93.
Integrated river basin management (IRBM) calls for participatory practices involving stakeholders along transnational river landscapes. Understanding the complex and diverse views regarding participation is a prerequisite for meaningful involvement of civil actors, especially in a transnational context. In a case study along the Lower Rhine river, we assessed and compared cognitive perceptions towards IRBM of citizen initiatives and nature organizations from Germany and the Netherlands and their previous experiences with participation processes.We found large differences between the four actor groups in motivations to participate as well as in levels of trust towards institutions. This study also showed different views on participation between the two countries with regard to the problem definition, nature images and the perceived relationships between government organisations on the one hand and citizen initiatives and nature organisations on the other hand.The findings suggest that views vary between citizen initiatives and nature organizations within a country and that cultural notions add to the complexity of transnational participation. In transnational participation processes, the varying views between actor groups should be taken into account, as well as the complexities among countries even within actor groups.  相似文献   
94.

Bursts of drinking water pipes not only cause loss of drinking water, but also damage below and above ground infrastructure. Short-term water demand forecasting is a valuable tool in burst detection, as deviations between the forecast and actual water demand may indicate a new burst. Many of burst detection methods struggle with false positives due to non-seasonal water consumption as a result of e.g. environmental, economic or demographic exogenous influences, such as weather, holidays, festivities or pandemics. Finding a robust alternative that reduces the false positive rate of burst detection and does not rely on data from exogenous processes is essential. We present such a burst detection method, based on Bayesian ridge regression and Random Sample Consensus. Our exogenous nowcasting method relies on signals of all nearby flow and pressure sensors in the distribution net with the aim to reduce the false positive rate. The method requires neither data of exogenous processes, nor extensive historical data, but only requires one week of historical data per flow/pressure sensor. The exogenous nowcasting method is compared with a common water demand forecasting method for burst detection and shows sufficiently higher Nash-Sutcliffe model efficiencies of 82.7% - 90.6% compared to 57.9% - 77.7%, respectively. These efficiency ranges indicate a more accurate water demand prediction, resulting in more precise burst detection.

  相似文献   
95.
Human-robot synchrony: flexible assistance using adaptive oscillators   总被引:1,自引:0,他引:1  
We propose a novel method for movement assistance that is based on adaptive oscillators, i.e., mathematical tools that are capable of extracting the high-level features (amplitude, frequency, and offset) of a periodic signal. Such an oscillator acts like a filter on these features, but keeps its output in phase with respect to the input signal. Using a simple inverse model, we predicted the torque produced by human participants during rhythmic flexion-extension of the elbow. Feeding back a fraction of this estimated torque to the participant through an elbow exoskeleton, we were able to prove the assistance efficiency through a marked decrease of the biceps and triceps electromyography. Importantly, since the oscillator adapted to the movement imposed by the user, the method flexibly allowed us to change the movement pattern and was still efficient during the nonstationary epochs. This method holds promise for the development of new robot-assisted rehabilitation protocols because it does not require prespecifying a reference trajectory and does not require complex signal sensing or single-user calibration: the only signal that is measured is the position of the augmented joint. In this paper, we further demonstrate that this assistance was very intuitive for the participants who adapted almost instantaneously.  相似文献   
96.
佳能(Canon)和东芝(Toshiba)的合资公司-SED公司宣布,将于2006年生产55英寸场致发射显示器(FED)。此外,SED公司还在2005年举行的两个会议上介绍了一些技术细节。本文将评述FED的某些技术信.  相似文献   
97.
液晶电视的优势使它很可能在本世纪的头十年内推翻CRT在电视市场的霸主地位。然而,那并不意味着真空显示器件将匆忙退出舞台,超薄型CRT会部分地与FPD显示器件在外型薄的优势方面展开竞争。甚至,它可以通过改进结构来显示出FED的特性。  相似文献   
98.
In this paper we will compare the electromigration and hot carrier properties of the old (gold based) and new (aluminium based) metallisation schemes as used in RF base station power amplifiers manufactured by Philips Semiconductors. We will show that the latest generation shows excellent reliability performance while the RF performance has been strongly enhanced. This has been obtained by optimizing the process and device architecture. Both results of electromigration measurements on test structures and electromigration degradation of full devices will be shown. It is concluded that the latest generation LDMOS RF amplifiers shows excellent RF and reliability performance while using an aluminium based metallisation scheme.  相似文献   
99.
We experimentally demonstrate a bit-rate of 47.4 Gb/s over 100 m of perfluorinated multimode graded-index plastic optical fiber (GI-POF) by exploiting discrete multitone (DMT) modulation with rate-adaptive bit-loading. The maximum achieved aggregate bit rate is 51.8 Gb/s including DMT transmission overhead (cyclic prefix and preambles) and the standard of 7% of forward-error-correction (FEC) overhead. This is achieved over an intensity-modulated direct-detection (IM-DD) link using a directly-modulated DFB laser (1300-nm) and a multimode fiber-coupled photodetector with a large diameter of 25-$mu$m. The bandwidth requirement is only 12 GHz due to the use of spectral-efficient modulation formats of up to 64-QAM.   相似文献   
100.
Mobile users and devices want to discover and share a growing range of information as the processing and storage capabilities of mobile devices grow. For example, users want to discover nearby networks, and location-based or time-sensitive user information contents. A mobile device may want to discover neighboring networks and the parameters required to access these networks so that it can intelligently decide which networks to use next, and use its existing network connection to authenticate with selected neighboring networks before it moves into the coverage areas of the selected networks. This can significantly reduce handoff delays. Existing service discovery frameworks are not effective for such neighboring network discovery or for discovering dynamic, location- or time-sensitive user information contents. This paper describes and evaluates a new approach—Mobile Information Services enabled by Mobile Publishing (MIS-MP)—for real time collection, discovery, and sharing of network and user information. With MIS-MP, mobiles take full advantage of the wealth of information they can accumulate during their routine mobility and use of networks to help each other to discover the information they want when and where they want it. This is accomplished by mobiles publishing the information they collect about the networks they visited, and the user information contents they learned or used, to make the information available to other mobiles. This paper presents analytical models and simulation results to evaluate the feasibility and performance of MIS-MP. It also describes a testbed implementation of MIS-MP and some of the lessons we learned. Tao Zhang is Director of Mobile Networking Research Group at Telcordia Technologies, Piscataway, New Jersey, USA. He develops and directs research and advanced development programs in mobile networking and applications, including mobility and applications across heterogeneous radio networks, mobile information services, vehicular networking, mobile peer-to-peer applications, sensor networking and applications, and collaborative networking .Dr. Zhang’s work has led to several new commercial products. He co-authored the book “IP-Based Next Generation Wireless Networks” published by John Wiley & Sons in 2004. He initiated the International Conference on Collaborative Computing: Networking, Applications, and Worksharing (CollaborateCom), and has been serving in various roles for it. Dr. Zhang holds 4 U.S. patents, with over 25 more pending. He received the 2000 Telcordia CEO Award (for most exceptional teams and individuals who have achieved a significant business success) and 2002 SAIC’s Executive Science and Technology Council Publication Prize. Eric van den Berg received his Ph.D. in Applied Mathematics from Cornell University in 1999. After obtaining his degree, he joined Telcordia Technologies, where he is a Research Scientist in Applied Research Department. His research interests include traffic modeling and performance analysis of IP- and wireless networks. He received the 2000 Telcordia CEO Award (for most exceptional individuals and teams who have achieved a significant business success) and the 2002 SAIC Executive Science and Technology Council Publication Prize. Sunil Madhani is a Distinguished MTS with Motorola where he manages the IP Realization team in Mobile Device Technology Office. He aims at working on unconventional and disruptive IP technologies. His current research focus is on convergent networks, dynamic mobility management and fast handoff in secured/seamless wireless LAN/WAN roaming. His past research includes registration/configuration protocols in wireless environment, application layer mobility management, secured Mobile IP, managed DOS attack sensor and TCP/IP boosters. Sunil Madhani holds MS (2002) in Engineering Management & System from Columbia University and MS (1997) in Computer Science from State University of New York.  相似文献   
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