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The objectives of this study were: (1) to assess nutrient flows and balances at land management systems and cropping seasons levels, and (2) to determine rate of nutrient depletion. The study was conducted in dry lands of Northern Kordofan, Sudan, at El Demokeya Forest Reserve (lat.13° 16′ ′′ ′N; long. 30° 29′ ′′ ′E, and alt. 560 m), over three cropping seasons (2002, 2003 and 2004). Flows and
Software development companies operating in market-driven domains need to deliver new and appealing software products at an increasing rate in order to stay competitive. This requires fast and efficient development of software for which the requirements are based on ever-changing market demands. Agile development claims to achieve increased development efficiency by performing the requirements eng
Cooperative content replication and request routing (C2R3) has emerged as a promising technique to enhance the efficiency of content delivery networks (CDN). Most existing approaches to C2R3 focus on efficient bandwidth usage and assume a hierarchical CDN architecture targeted towards the delivery of specific content types (e.g., video). Therefore, C2R3 problem of covering the broad range of conte
The design of a digital baseband for a low power wireless receiver in 65 nm CMOS is presented. It consists of decimation filtering, matched filters for data detection, and preamble based synchronization. The circuit was designed using low threshold devices in both low power (LP-LVT) and general-purpose (GP-LVT) domains. The fabricated circuits were functionally verified, and silicon measurements s
In this paper we present an analysis of the effects of antenna placement on the radio channel properties for Vehicle-to-Vehicle communications based on measurements performed in three different propagation scenarios; highway, urban and rural. Four omni-directional antennas were mounted at four different positions: roof, bumper, left-side mirror and inside windscreen of two standard station wagons
The ambitious goal of the upcoming IEEE 802.11ax (HEW) standard for wireless LANs (WLANs) to enhance throughput by four times (and beyond), compared with IEEE 802.11ac, demands a radical improvement of present medium access control (MAC) functionality. To this end, a promising paradigm would be a graceful migration towards new MAC protocols which incorporate higher certainty in their decisions. Ho
The findings from a user study regarding particular ob- servable “interaction patterns” in the interaction during a “guided tour” are summarized in this paper.
Video-on-Demand (VoD) and video sharing services account for a large percentage of the total downstream Internet traffic. In order to provide a better understanding of the load on these services, we analyze and model a workload trace from a VoD service provided by a major Swedish TV broadcaster. The trace contains over half a million requests generated by more than 20000 unique users. Among other
This paper presents a detailed description of a propagation channel measurement campaign performed in a warehouse environment and provide a comprehensive channel model for this environment. Using a vector network analyzer (VNA), we explored both Line-of-sight(LOS) and Non-Line-of-sight (NLOS) scenarios over a 2-8 GHz frequency range. We extracted both small-scale and large-scale channel parameters
Governmental organisations are becoming more critically dependant on IT systems such as communication systems or patient data systems, both for their everyday tasks and their role in crisis relief activities. Therefore it is important for the organisation to analyse the reliability of these systems as part of the organisation’s risk and vulnerability analysis process. This paper presents a practic
Low-density parity-check convolutional (LDPCC) codes, also known as spatially coupled LDPC codes, can be decoded using a message passing algorithm. In order to limit decoding latency and complexity, windowed decoding can be applied. Updates within the window can be performed either in parallel or serially. However, simulation results show that uniform updating schedules do not provide the expected
In this paper, we confirm that angle and polarization diversities are indeed the dominant diversity mechanisms of a recently proposed compact six-port MIMO antenna array, as it exhibits similar effective degree-of-freedom (EDOF) performance as that of the ideal array with co-located antenna elements evaluated in propagation scenarios with different angular spreads. Furthermore, the same approach c
We find good rate 2/3 and 3/4 convolutional codes for use with iterative decoding (turbo equalization) of coded intersymbol interference with AWGN. The method is based on the input-output bit error rate characteristic of the convolutional BCJR decoder module. An analysis leads to an equivalent minimum distance under the required intrinsic subtraction, which depends on free distance and an input-ou
With the introduction of new cellular phone standards with increased modulation complexity and signal bandwidth, the design of efficient transmitters will be a major challenge. With this in mind a number of switched mode transmitter architectures are described, both polar and Cartesian ones. The most promising candidates use a combination of supply voltage modulation and other techniques, such as
One of the exciting emerging uses of DSRC/WAVE technology is the ability to monitor real-time road traffic conditions with high resolution, using beacons transmitted by individual vehicles, and make informed traffic control decisions such as traffic light timing or route advice. However, previous studies have shown that achieving a high level of accuracy in traffic density estimation requires very
This chapter discusses major results and conclusions from Special Interest Group C bringing together various aspects of mobile to mobile communication from all working groups. Vehicle-to-vehicle communication scenarios are emphasized. Traffic telematics applications are currently under intense research and development for making transportation safer, more efficient, and cleaner. Communication sys
A semantic editor, providing services like completion and code browsing, can help users to quickly develop high-quality source code. However, a lot of languages still lack semantic editor support due to the difficulty and costs of development. Tool generation and reuse can greatly alleviate this development task. Specifically, tool generation from a formal specification, such as reference attribut
