A service level model and Internet mobility monitor

Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.     

Single-chip image sensors with a digital processor array

The architectures, implementation and applications of two smart sensors, LAPP and PASIC, are described. The basic idea of these two designs is to integrate an image sensor array with a digital processor array in a single chip. The integrated camera-and-processor eliminates the bottleneck of sequential image read-out that characterizes conventional systems. They provide fast, compact and economic solutions for tasks such as industrial inspection, optical character recognition and robot vision.     

Extending Global IP Connectivity for Ad Hoc Networks

Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed.     

Multiband RF-sampling receiver front-end with on-chip testability in 0.13 μm CMOS

In this paper a flexible RF-sampling front-end primarily intended for WLAN standards operating in the 2.4 GHz and 5–6 GHz bands is presented. The circuit is implemented with on-chip Design for Test (DfT) features in 0.13 μm CMOS process. The front-end consists of a wideband LNA, a sampling IQ down-converter implemented as switched-capacitor decimation filter, test attenuator (TA), and RF detectors. The architecture is generic and scalable in frequency. It can operate at a sampling frequency up to 3 GHz and RF carrier up to 6 GHz with 2× subsampling. The selectable decimation factor of 8 or 16 makes the A/D conversion feasible. The frequency response, linearity, and NF of the whole front-end have been measured. The power consumption of complete RF front-end is 176 mW. The on-chip DfT features are helpful in reduction of overall test cost and time in volume production. The measurement results show the feasibility of DfT approach for multiband radio receiver design using standard CMOS process.     

Electrophysiological and chemical analysis of sex pheromone communication system of the mottled umber,Erannis defoliaria (Lepidoptera: Geometridae)

(Z,Z,Z)-3,6,9-nonadecatriene (Z3,Z6,Z9–19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from femaleErannis defoliaria. The two components were found in a 13 ratio, with the main component,Z3,Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding toZ3,Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding toZ3,Z6,Z9–19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland ofColotois pennaria, and males ofC. pennaria andAgriopis marginaria were trapped by the mixture of the identified compounds.     

Structure-activity relationships for chain-shortened analogs of (Z)-5-decenyl acetate,a pheromone component of the turnip moth,Agrotis segetum

Structure-activity relationships for chain-shortened analogs of (Z)-5-decenyl acetate, a pheromone component of the turnip moth,Agrotis segetum, have been studied by electrophysiological single-sensillum technique and interpreted in terms of a previously reported receptor-interaction model. The results indicate that the terminal methyl group, as well as the acetate group, interacts with highly complementary receptor sites. The terminal alkyl chain is suggested to interact with a hydrophobic pocket extending over the two methylene groups closest to the terminal methyl group. The amounts of stimulus actually released from the odor source have been studied. The results demonstrate the necessity to take differences of volatility into account in comparisons of electrophysiological data for compounds of different chain lengths. It is shown that relative vapor pressures may to a good approximation be employed to estimate correction factors.Schiff., Lepidoptera: Noctuidae.     

Developments toward a microfluidic system for long-term monitoring of dynamic cellular events in immobilized human cells

A microfluidic system for long-term real-time monitoring of dynamic cellular events of immobilized human cells was investigated. The luciferase reporter gene activity in the reporter cell line HFF11, based on HeLa cells, was used as the model system. The cells were immobilized on silicon flow-through microchips and continuously supplied with a cell medium at 2 microL/min while maintaining the chip at 37 degrees C. The HFF11 cell line was designed for high-throughput screening of ligands for seven-transmembrane receptors. When a ligand binds, the receptor is activated and a cascade of intracellular reactions starts, ending with the synthesis of the reporter protein Photinus luciferase. The major goal was to develop a microfluidic system for continuous long-term assaying of the intracellular reporter gene activity in real time and determine the conditions, which could minimize cells stress and hence unspecific expression of the reporter gene. In the resulting microfluidic system and assay protocol, the cell microchip could be kept and assayed for a period up to 30 h. The developed system and data outcome was compared with a corresponding microtiter plate performed with the same cell line to highlight the advantages obtained in the microfluidic format.     

Problem identification in maintenance modelling: a case study

This paper is concerned with a problem identification and problem focus process in maintenance modelling. It endeavours to describe the process of moving from vague problem understanding towards more specific problem formulation and problem focus in the pursuit of practical decision making. This process was conducted using several analytical tools that complemented each other such as regression analyses, snapshot modelling and delay time modelling. As in many case studies related to maintenance modelling, this study also makes use of the experience of experts. It can be seen from the paper that subjective data estimates can prove to be a useful input for modelling. The analysis shows how simple modelling of maintenance problems can provide useful insights and better understanding of the problem in hand.     

Conceptions and operational use of value and waste in lean manufacturing – an interpretivist approach

In this article, we explore how the key concepts of lean manufacturing, value, value adding and waste are conceived and operationally used by Lean trainers in operational work processes. A comparative case study with a mixed method approach, using an explanatory sequential design, was conducted. This means that a set of quantitative data were collected, which was followed by the collection of qualitative data with the purpose of explaining and understanding the quantitative measures. An interpretivist approach is used as a framework, which implies a perspective on contemporary operations management paradigms, such as lean manufacturing, as a continuous construction of inter-subjective experiences. What becomes evident in the empirical findings is that there are both similarities and differences in the Lean trainers conceptions and use of value adding and waste. The similarities and differences can be explained by variations in two dimensions: (a) the character of the work process, which ranges between mechanical and craftsmanship, and (b) Lean trainers approach to key concepts, which ranges between being rule-based and reflective. By using a research design where the concepts of value adding and waste were used simultaneously, and adopting an interpretivist approach on lean manufacturing, we were able to reveal conditions that in other cases remain hidden.     

Landscape heritage objects’ effect on driving: A combined driving simulator and questionnaire study

According to the literature, landscape (panoramas, heritage objects e.g. landmarks) affects people in various ways. Data are primarily developed by asking people (interviews, photo sessions, focus groups) about their preferences, but to a lesser degree by measuring how the body reacts to such objects. Personal experience while driving a car through a landscape is even more rare. In this paper we study how different types of objects in the landscape affect drivers during their drive. A high-fidelity moving-base driving simulator was used to measure choice of speed and lateral position in combination with stress (heart rate measure) and eye tracking. The data were supplemented with questionnaires. Eighteen test drivers (8 men and 10 women) with a mean age of 37 were recruited. The test drivers were exposed to different new and old types of landscape objects such as 19th century church, wind turbine, 17th century milestone and bus stop, placed at different distances from the road driven. The findings are in some respect contradictory, but it was concluded that that 33% of the test drivers felt stressed during the drive. All test drivers said that they had felt calm at times during the drive but the reason for this was only to a minor degree connected with old and modern objects. The open landscape was experienced as conducive to acceleration. Most objects were, to a small degree, experienced (subjective data) as having a speed-reducing effect, much in line with the simulator data (objective data). Objects close to the road affected the drivers’ choice of’ lateral position. No significant differences could be observed concerning the test drivers’ gaze between old or modern objects, but a significant difference was observed between the test drivers’ gaze between road stretches with faraway objects and stretches without objects. No meaningful, significant differences were found for the drivers’ stress levels as measured by heart rate.