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101.
Packaging fresh lamb in a vacuum (VAC) versus a 100% CO2 modified atmosphere (MAP) may influence product shelf-life and the bacterial communities. While VAC is a common packing method and 100% CO2 MAP is used in some countries, there is little information about how these different techniques affect the growth of spoilage bacteria and sensory attributes of lamb. The aim of this study was to assess changes in microbiological and organoleptic properties, and determine differences in microbial communities by terminal restriction fragment length polymorphism (TRFLP) and 454 pyrosequencing, in bone-in (BI) and bone-out (BO) MAP- and VAC-packed lamb shoulders stored at −0.3 °C over 12 wk. VAC and MAP lamb shoulders were acceptable in sensory test scores over 12 wk of storage at −0.3 °C, despite total viable count (TVC) and lactic acid bacteria (LAB) levels increasing to 8 log10 CFU/cm2 for VAC lamb and 4–6 log10 CFU/cm2 for MAP lamb. Similar to the sensory results, there were no significant differences in microbial communities between BI and BO product. However, types of bacteria were different between VAC and MAP packaging. Specifically, while VAC shoulder became dominated by Carnobacterium spp. in the middle of the storage period, the MAP shoulder microbial population remained similar from the start until later storage times.  相似文献   
102.
Variations in texture were determined for 10 day aged raw and cooked Longissimus thoracis (LT) muscle from 436 bulls of 15 European cattle breeds slaughtered at an age of 13–16 months. Variations in texture were related to differences in pH 24 h post-mortem, sarcomere length, collagen characteristics and lipid content. The shear force of cooked meat samples varied from 43.8 to 67.4 N/cm2. Simmental, Highland and Marchigiana cattle had the highest shear force values and Avileña-Negra Ibérica, Charolais, Casina and Pirenaica cattle had the lowest values. Cooked meat toughness showed a weak negative correlation to lipid content (P < 0.001) but no correlation to collagen characteristics. Raw meat texture measured by compression correlated positively (P < 0.001) with total and insoluble collagen. In conclusion, collagen characteristics showed correlation to raw meat texture but not to cooked meat toughness of LT muscle in European young bulls.  相似文献   
103.
Listening to music on personal, digital devices whilst mobile is an enjoyable, everyday activity. We explore a scheme for exploiting this practice to immerse listeners in navigation cues. Our prototype, ONTRACK, continuously adapts audio, modifying the spatial balance and volume to lead listeners to their target destination. First we report on an initial lab-based evaluation that demonstrated the approach’s efficacy: users were able to complete tasks within a reasonable time and their subjective feedback was positive. Encouraged by these results we constructed a handheld prototype. Here, we discuss this implementation and the results of field-trials. These indicate that even with a low-fidelity realisation of the concept, users can quite effectively navigate complicated routes.
Matt Jones (Corresponding author)Email:
Steve JonesEmail:
Gareth BradleyEmail:
Nigel WarrenEmail:
David BainbridgeEmail:
Geoff HolmesEmail:
  相似文献   
104.
Transporting QoS adaptive flows   总被引:4,自引:0,他引:4  
Distributed audio and video applications need to adapt to fluctuations in delivered quality of service (QoS). By trading off temporal and spatial quality to available bandwidth, or manipulating the playout time of continuous media in response to variation in delay, audio and video flows can be made to adapt to fluctuating QoS with minimal perceptual distortion. In this paper, we extend our previous work on a QoS Architecture (QoS-A) by populating the QoS management planes of our architecture with a framework for the control and management of multilayer coded flows operating in heterogeneous multimedia networking environments. Two key techniques are proposed: i) an end-to-end rate-shaping scheme which adapts the rate of MPEG-coded flows to the available network resources while minimizing the distortion observed at the receiver; and ii) an adaptive network service, which offers “hard” guarantees to the base layer of multilayer coded flows and “fairness” guarantees to the enhancement layers based on a bandwidth allocation technique called Weighted Fair Sharing.  相似文献   
105.
Random forests is currently one of the most used machine learning algorithms in the non-streaming (batch) setting. This preference is attributable to its high learning performance and low demands with respect to input preparation and hyper-parameter tuning. However, in the challenging context of evolving data streams, there is no random forests algorithm that can be considered state-of-the-art in comparison to bagging and boosting based algorithms. In this work, we present the adaptive random forest (ARF) algorithm for classification of evolving data streams. In contrast to previous attempts of replicating random forests for data stream learning, ARF includes an effective resampling method and adaptive operators that can cope with different types of concept drifts without complex optimizations for different data sets. We present experiments with a parallel implementation of ARF which has no degradation in terms of classification performance in comparison to a serial implementation, since trees and adaptive operators are independent from one another. Finally, we compare ARF with state-of-the-art algorithms in a traditional test-then-train evaluation and a novel delayed labelling evaluation, and show that ARF is accurate and uses a feasible amount of resources.  相似文献   
106.
This paper documents the design, competing systems, results, and conclusions of the CADE-14 ATP System Competition (CASC-14).  相似文献   
107.
Abstract

This paper describes some trends and issues in the application of information technology in organisations. Technology trends are outlined in the areas of computing power, telecommunications, networking, software and standards. Some trends in the applications of IT are described with respect to developments in information systems and office automation. Some differences in the likely role of IT in the industrialised and developing countries are discussed. The second half of the paper deals with issues in the management of IT applications in organisations, and issues are identified as being political, organisational and social in nature in addition to technical. A social systems framework is proposed for the analysis of these issues. Some specific IT issues are then discussed involving alternative stakeholder perspectives, the analysis of decision making processes, the process of consultation and communication and the organisational impacts of IT applications.  相似文献   
108.
Abstract

The use of information technology (IT) in developing countries has attracted a considerable amount of attention in recent years. However, the research in this area is largely fragmented, and there is a need to consolidate efforts in order to make research more effective. Theory can provide a basis for this consolidation process by allowing communication between different researchers and also between researchers and practitioners. The primary objective of this paper is to describe aspects of the state of existing theory in the field of IT in developing countries, and discuss possible research directions for the future. A total of 199 articles were analyzed to describe existing research themes, and future directions are discussed in terms of level of analysis, research methods, and research reports.  相似文献   
109.
Abstract. This short paper is a response to the article by McGrath in this issue which argues that information systems (IS) researchers need to be more explicit about 'being critical'. I accept her point, and I use this paper to offer a sketch of my personal journey in learning about criticality, and some thoughts from where I am now on various aspects of carrying out critical IS research.  相似文献   
110.
R. Geoff Dromey 《Software》1986,16(11):981-986
A refinement to a well-known selection algorithm is described. The refinement results in a useful improvement in the performance of the original algorithm, particularly when the selection index is small relative to the median.  相似文献   
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