Central Collection Point Research Articles

Security analysis and secured access design for networks of image remote sensing

The secured access is studied in this paper for the network of the image remote sensing. Each sensor in this network encounters the information security when uploading information of the images wirelessly from the sensor to the central collection point. In order to enhance the sensing quality for the remote uploading, the passive reflection surface technique is employed. If one eavesdropper that exists nearby this sensor is keeping on accessing the same networks, he may receive the same image from this sensor. Our goal in this paper is to improve the SNR of legitimate collection unit while cut down the SNR of the eavesdropper as much as possible by adaptively adjust the uploading power from this sensor to enhance the security of the remote sensing images. In order to achieve this goal, the secured energy efficiency performance is theoretically analyzed with respect to the number of the passive reflection elements by calculating the instantaneous performance over the channel fading coefficients. Based on this theoretical result, the secured access is formulated as a mathematical optimization problem by adjusting the sensor uploading power as the unknown variables with the objective of the energy efficiency maximization while satisfying any required maximum data rate of the eavesdropper sensor. Finally, the analytical expression is theoretically derived for the optimum uploading power. Numerical simulations verify the design approach.

Fecal Sludge Management in Low Income Settlements: Case Study of Nakuru, Kenya.

Introduction: In order to meet the sustainable development goals targets of sanitation, countries aim to increase access to safely managed sanitation services for its citizens. Safely managed sanitation services refers to improved sanitation technologies that are not shared with other households and where excreta is treated and disposed; or stored, transported and treated off-site. In most Sub-Saharan Africa (SSA) countries, on-site sanitation facilities such as latrines and septic tanks are common, with low-income urban settlements mainly using pit latrines. However, little is documented about the management of sludge from these facilities, especially in low income settlements in secondary and emerging cities. This lack of data is a major hindrance to public health, development and planning efforts by governments and planning agencies. This study specifically assesses practices and challenges along the sanitation value chain related to containment, emptying, transportation, treatment and recycling of fecal sludge.Methods: The study was carried out in low income settlements in Nakuru, a secondary city in Kenya. Over half the population in Nakuru live in low income areas and majority of these residents use pit latrines. A case study design was selected for this study and data was collected using qualitative methods. Data was collected through In-depth interviews and Focus Group Discussions using in depth interview guide and focus group discussion guides that had questions on sanitation practices along the value chain, challenges, opportunities available, and recommendations for improvement. Analysis was done through content analysis by reading the transcripts multiple times to gain a sense of the flow of the discussion. Thereafter, coding was done by following emergent issues and thereafter categories were identified which formed the basis for providing a picture of FWM practices in the settlements.Results: On site sanitation facilities are dominant in the settlements, but they are few and are shared by several households. These facilities were unclean, and they filled up at a fast rate because of the high number of users. The latrines were emptied by manual emptiers who used mechanized equipment but complemented with manual emptying using buckets. Sludge was transported to a central collection point using large and small scale means of transportation, before transfer to the treatment site for final treatment and disposal. Various stakeholders are involved in capacity building of emptiers as well as in the transportation, treatment and disposal of fecal sludge in the settlements. Challenges along the stages of the value chain included negative community perceptions and attitudes toward fecal sludge management.Conclusion: The results highlight the need to address the challenges along the chain by involvement of state and non-state actors. Low income areas have high populations and thus contribute huge amounts of fecal sludge. Deliberate efforts to consolidate such data from low income areas will result in availability of data, and informed decision making for stakeholders at national and international levels.

Potential advantages in heat and power production when biogas is collected from several digesters using dedicated pipelines - A case study in the “Province of West-Flanders” (Belgium)

In the case study “West-Flanders” costs of electricity and heat production are estimated if a dedicated biogas grid using pipelines would be implemented to centralize energy production in a region. Heat may not be used effectively at digester sites, e.g. because of a change in treatment of digestate. A large scale centralized combined heat and power (CHP) engine can produce additional electrical power at a hub, i.e. central collection point, and has lower specific costs compared to decentralized CHPs at digester sites. A biogas transport model is used to calculate transport costs in a grid. These costs, partly balanced by a scale advantage in CHP costs, are attributed to the additional electrical energy (80%) and heat (20%) produced. If the hub is at a digester site, costs of additional electricity can be as low as 4.0 €ct kWhe−1 and are in many cases below 12 €ct kWhe−1, i.e. in the same order of magnitude or lower than costs of electricity from biogas produced using separate CHPs at the different digester sites; costs of heat at the hub show to be lower than 1 €ct kWhth−1 assuming an effective heat use of 50%. In case a hub is situated at a location with high potential heat demand, i.e. a heat sink, transport of biogas from one digester only to a central located hub can provide 3.4 MWth of heat at 1.95 €ct kWhth−1. For such a centrally located hub additional electrical energy costs show to be slightly higher, but with three or more digesters these costs are lower than 20 €ct kWhe−1 and heat costs are around 0.5 €ct kWhth−1. With a centralized hub more renewable energy is produced, i.e. a more efficient use of biomass feedstock. It is concluded that costs for additional electricity and heat can be at a competing level and scale advantages in a CHP can be a driver to collect biogas at a hub using a biogas grid.

Split and Merge LEACH Based Routing Algorithm for Wireless Sensor Networks

Hierarchical routing and clustering mechanisms in Wireless Sensor Networks (WSNs) help to reduce both the energy consumption, and the overhead that is created when all the sensor nodes in the network are sending information to the central data collection point or base station. LEACH (Low Energy Adaptive Clustering Hierarchy) is one of the most well-known energy efficient clustering algorithms for WSNs. In this paper, we extend the LEACH protocol to (LEACH-SM) protocol by introducing a Split and Merge stage to improve the performance and robustness. We consider the following design aspects: non-uniform distribution of sensors, cluster re-formation by splitting or merging clusters conditionally, routes maintenance, and nodes mobility. OPNET, a well-known simulator tool, is used to simulate LEACH-SM in order to evaluate the performance of the proposed protocol. Simulation results and comparisons with existing protocols show the effectiveness and strength of the proposed protocol in terms of enhancing the lifetime of the whole sensor network, where sensors are either static or mobile with low speed.

Monaro dieback: simple answers are too simple

ABSTRACTRoss and Brack (2015) reported the first formal survey of dieback of Eucalyptus viminalis occurring across the Monaro Plains of south-eastern New South Wales (NSW). The survey found that the dieback covered about 2000 km2 of public and private land, and that there was no significant correlation between the observed dieback and any of the environmental or management parameters studied. Jurskis (2016) claims that the dieback in the Monaro is ‘not difficult to explain’, as it is simply due to the absence of grazing or regular light fire. We argue that this hypothesis cannot explain the ‘Monaro dieback’, and further research is required to determine the underlying cause/s. Since publication of the original survey, the authors have received a wide range of reports from academic and general observers about dieback of various species in various environments across the country. Recent observations now suggest that the ‘Monaro’ dieback has extended beyond the original boundary and into other Eucalyptus species. We emphasise the need for an agency or organisation to act as a central collection point for geographically referenced and time-stamped photographs or descriptions from the public in order to better monitor tree health across the country.

The effect of giving respondents time to think in a choice experiment: a conditional cash transfer programme in South Africa

AbstractWe conducted a choice experiment (CE) to estimate willingness to accept (WTA) values for a planned conditional cash transfer (CCT) programme designed to increase toilet use in South Africa. The payment is made conditional on using a toilet and bringing urine to a central collection point. In a split-sample approach, a segment of respondents were given time to think (TTT) (24 hours) about their responses, while the remaining respondents had to answer immediately. We found significant differences in the choice behaviour between the subsamples. To validate the stated preferences with actual behaviour, a CCT programme was implemented afterwards. The stated WTA estimates were far below those revealed by actual behaviour for both subsamples. Contrary to our expectations, the TTT group had underestimated their actual WTA values by an even larger margin. The preferences for various attributes were nevertheless useful in informing the design of the real intervention.

Decentralised LTL monitoring

Users wanting to monitor distributed or component-based systems often perceive them as monolithic systems which, seen from the outside, exhibit a uniform behaviour as opposed to many components displaying many local behaviours that together constitute the system's global behaviour. This level of abstraction is often reasonable, hiding implementation details from users who may want to specify the system's global behaviour in terms of a linear-time temporal logic (LTL) formula. However, the problem that arises then is how such a specification can actually be monitored in a distributed system that has no central data collection point, where all the components' local behaviours are observable. In this case, the LTL specification needs to be decomposed into sub-formulae which, in turn, need to be distributed amongst the components' locally attached monitors, each of which sees only a distinct part of the global behaviour. The main contribution of this paper is an algorithm for distributing and monitoring LTL formulae, such that satisfaction or violation of specifications can be detected by local monitors alone. We present an implementation and show that our algorithm introduces only a negligible delay in detecting satisfaction/violation of a specification. Moreover, our practical results show that the communication overhead introduced by the local monitors is generally lower than the number of messages that would need to be sent to a central data collection point. Furthermore, our experiments strengthen the argument that the algorithm performs well in a wide range of different application contexts, given by different system/communication topologies and/or system event distributions over time.

Multidimensional Fuzzy Control System Development of Oil Transportation and Treatment Technological Processes Based on the Input/Output Parameters Model in the Precise Terms Set Form

As pumps and pumping stations of oil collecting, maintaining reservoir pressure, transportation and treatment processes account for over 50 % of oil and gas enterprises estimated total cost of electricity, relevant issue is the development and application of intelligent control systems for energy efficiency of these processes. For the booster pump station as a multivariable nonlinear control object are proposed: a structure in which the function of regulating valves transferred to the pumps with frequency speed control; conceptual model with seven inputs and five outputs (adjustable) variables, which is the basis for constructing three-dimensional fuzzy controller with not-fuzzy terms to stabilize and improve the energy efficiency of oil transportation and treatment processes and minimize energy losses. In this paper we propose a control system of pumping station on the basis of multidimensional fuzzy logic controller with compensation of the mutual influence of control loops in the form of an additional system of production rules that helped to stabilize the liquid level at 2.5 m given level with an absolute error of ± 0.2 m and thus improve quality oil emulsion on the installation of oil and gas refining central collection point.

Approximate dynamic programming for automated vacuum waste collection systems

The collection and treatment of waste poses a major challenge to modern urban planning, particularly to smart cities. To cope with this problem, a cost-effective alternative to conventional methods is the use of Automated Vacuum Waste Collection (AVWC) systems, using air suction on a closed network of underground pipes to transport waste from the drop off points scattered throughout the city to a central collection point. This paper describes and empirically evaluates a novel approach to defining daily operation plans for AVWC systems to improve quality of service, and reduce energy consumption, which represents about 60% of the total operation cost. We model a daily AVWC operation as a Markov decision process, and use Approximate Dynamic Programming techniques (ADP) to obtain optimal operation plans. The experiments, comparing our approach with the current approach implemented in some real-world AVWC systems, show that ADP techniques significantly improve the quality of AVWC operation plans.

Lifetime analysis for wireless sensor networks

The sensor nodes of wireless sensor networks WSNs have the dual function of gathering information and relaying it to a central collection point, the sink. In this paper, we derive connectivity, as expressed by the probability that a node lies on a path to the sink, as a function of the probability that adjacent cells in a grid are connected. The nodes are assumed to have two modes of operation, the active and sleep states and the energy is consumed only in the active state. For battery powered nodes, lifetime is an important factor. The effect of the demise of nodes on the nodal density and, in turn, on network connectivity is quantified. The novelty of the results is that they determine the degree of connectivity in networks with finite number of nodes, unlike to many results in the literature which are asymptotic and for full connectivity.

Flow‐based Approaches in Network Management: Recent Advances and Future Trends

The continuous increase of line speeds and throughput in modern computer networks has considerably stimulated the usage of aggregation-based monitoring techniques for network management in the past years. Amongst those, flow-based approaches have become extremely popular among researchers and operators due to the wide availability of hardware and software flow exporters and their quasistandardized exporting formats, such as NetFlow or IPFIX. While flow-based monitoring was originally used for simple diagnosing and accounting purposes, researchers are now proposing flow-based approaches for a wide range of application fields, such as intrusion detection, traffic classification, and resource management. Several trends can be identified in flow-based monitoring. First of all, we observe more and more attempts to close the gap between packet-based and flow-based monitoring. As the latter was originally proposed as an efficient and scalable alternative to Deep Packet Inspection (DPI) in high-speed networks, the most recent flow exporters allow for enriching flow data with application-layer information, for example. It can be expected that this will lead to new approaches and solutions for network management problems. Second, IPFIX is evolving towards a generic protocol for exporting structured data. For example, the IPFIX Working Group has investigated the use of IPFIX for exporting SNMP Management Information Base (MIB) variables. Another example was showcased at the IETF-87 meeting, where room temperatures were exported to a central collection point using IPFIX. Since IPFIX is a push protocol, it will provide an effective way for network managers to continuously collect information from remote hosts. Finally, new environments, such as Clouds and Software Defined Networks (SDN), demand new flow-based solutions for their monitoring and management. OpenFlow, the most prominent protocol for SDN, is flow-based, highlighting the need for network managers to monitor and understand trends in flows through their networks. Thus, the goal of this Special Issue of the International Journal on Network Management is to present innovative flow-based approaches and solutions for network management tasks, as well as new methods and technologies for the generation, processing and analysis of flow information. The articles in this Special Issue present research results and a survey on the usage of flow-based approaches, and on the design and implementation of high-speed monitoring devices. A total of 22 submissions was received for this Special Issue, for which we wish to thank all authors. Three papers did not go through the full review process because they were identified early as out of scope. Each of the remaining 19 papers received at least three independent reviews. In total, 47 reviewers participated in the review process. Based on their reviews, seven papers were finally selected for publication.

Modeling energy consumption in automated vacuum waste collection systems

In a world where resources are scarce and urban areas consume the vast majority of these resources, it is vital to make cities greener and more sustainable. A smart city is a city in which information and communications technology are merged with traditional infrastructures, coordinated and integrated using new digital technologies. The increasing amount of waste generated, and the collection and treatment of waste poses a major challenge to modern urban planning in general, and to smart cities in particular. To cope with this problem, automated vacuum waste collection (AVWC) uses air suction on a closed network of underground pipes to transport waste from the drop off points scattered throughout the city to a central collection point, reducing greenhouse gas emissions and the inconveniences of conventional methods (odours, noise, etc.). Since a significant part of the cost of operating AVWC systems is energy consumption, we have developed a model with the aim of applying constraint programming technology to schedule the daily emptying sequences of the drop off points in such a way that energy consumption is minimized. In this paper we describe how the problem of deciding the drop off points that should be emptied at a given time can be modeled as a constraint integer programming (CIP) problem. Moreover, we report on experiments using real data from AVWC systems installed in different cities that provide empirical evidence that CIP offers a suitable technology for reducing energy consumption in AVWC.

Waste Management Motivational Factors in Bayelsa State

The solid waste management problem in Nigeria is enormous. Heaps of waste can be seen all over the country's roadsides, in its bodies of water, and in other unoccupied places resulting in a series of health and environmental problems. This research evaluates possible waste management motivational factors in the state of Bayelsa. A semi-structured questionnaire was used to gather the primary data, which was distributed to households at the headquarters of the eight Local Government Areas (LGAs) of the state. The secondary data was based on a review of the existing literature. Content analysis was utilized for the secondary data, while SPSS was used to analyze the primary data. The results of this study show that waste separation, reuse, recycling, and composting are only performed by a handful of people in the state. Waste management in the state is marred by inadequate central waste collection points, poor city planning, inadequate funding, inadequate enlightenment, unfavorable attitude of the people toward waste management, absence of waste management facilities, inadequate enforcement of laws, absence of engineered landfills and the existence of illegal dumpsites around the state, and inadequately trained personnel. Understanding the problem in question affects the intentions and behavior of Bayelsa's citizens in different ways, which further affects their action or inaction. The individual's assumption of responsibility is paramount to their performance. Execution and implementation of effective waste collection services statewide could motivate citizens to dispose of their waste properly. Citizens' behavior toward waste management could be determined by how well they know and understand the current management strategies, their gender and social class, the availability of current waste collection and disposal infrastructures, and existing policies and laws.

05 An evaluation of the “Just in Case” bag anticipatory prescribing scheme in Devon 2011-2013

Background“Just in Case” anticipatory prescribing schemes are seen as one way of ensuring that patients nearing the end of their lives can have access to rapid relief of symptoms at...

P128 The acceptability of using soccer clubs as venues for chlamydia screening in young men: results from a qualitative study

BackgroundMany non-clinical, including sports, settings have been used in an attempt to screen more men for Chlamydia. While feasible there is very little research exploring their acceptability among users of these settings.ObjectiveWe explored the acceptability of, and the best way to deliver, Chlamydia screening in soccer clubs among young men who play amateur soccer.Methods18 semi-structured, face-to-face interviews with men aged between 18 and 35 who play soccer in London-based non-professional leagues. Interviews were carried out from October to December 2011 and analysed using a framework approach.ResultsSoccer clubs are acceptable venues to access Chlamydia screening because they offer several potential benefits over screening in traditional settings. Importantly they are discreet testing venues and allow screening to take place within the context of normal daily routines. Having testing kits handed out to all team members by a senior member of the club (captain/coach/manager) or a visiting health care professional (HCP) meant that no one would feel singled out for testing and overcome barriers to asking for, or collecting a kit from central collection points. While some men preferred to use the test kit there and then and return samples to a collection point at the club, others preferred to use kits at home and return samples to the laboratory by post. However, concerns about confidentiality and test tampering meant that some men favoured a visiting HCP to coordinate testing rather than a member of the club.ConclusionSoccer clubs appear to be acceptable venues for young men who play soccer to access self-collected testing kits for Chlamydia. Processes for accessing, using and returning test kits should be discreet, easy and quick. We will be developing testing pathways in soccer clubs to pilot in six London clubs during the 2012–2013 season.

Zone-based routing protocol with mobility consideration for wireless sensor networks

Hierarchical routing and clustering mechanisms in Wireless Sensor Networks (WSN) help to reduce the energy consumptions and the overhead created when all the sensor nodes in the network are sending information to the central data collection point. Most of the routing and clustering protocols proposed for WSN assume that the nodes are stationary. However, in applications like habitat monitoring or search and rescue, that assumption makes those clustering mechanisms invalid, since the static nature of sensors is not real. In this paper, we propose Zone-based Routing Protocol for Mobile Sensor Networks (ZoroMSN) that considers the design aspects such as mobility of sensors, zones and routes maintenance, information update and communication between sensor nodes. Simulation results show the effectiveness and strengths of the ZoroMSN protocol such as a low routing and mobility overhead, while achieving a good performance in WSN using small zone sizes and sensors with low speed. Simulation results also show that ZoroMSN outperforms existing LEACH-ME and LEACH-M protocols in terms of network lifetime and energy consumptions.

Stochastic Optimization Model for Electric Power System Planning of Offshore Wind Farms

In the coming years, an extensive development of large-scale offshore wind farms (OWFs) is foreseen in Europe. Electric power systems of OWFs need to be optimized in order to minimize investment and operational costs. This paper proposes a comprehensive decision support model that covers the three key factors that characterize the design of ac electric power systems of OWFs: investment costs of the components, system efficiency, and system reliability. Stochasticity of wind speed and reliability of the main system components are also considered. The main decisions concern the layout and the cross-sections of cable connections and the location of the central collection point for the medium voltage cables. GAMS language has been used to implement the model. It has been validated using a real OWF. An application example has also been carried out to explain the extension of the model to OWFs with dc power systems. The proposed model is useful for basic engineering design and as a decision tool for planning the electric power system of OWFs.

Harvesting vineyard pruning residues for energy use

Comparative tests of 4 systems for harvesting vineyard pruning residues were carried out using 1) a square baler; 2) a round baler; 3) a comminuter (or shredder) with drop-down re-usable containers (big bags); 4) a comminuter with built-in dumping bin. All machines were light enough for towing or carrying behind compact vineyard tractors. The machines were tested in Central Italy, on 10 ha of hill vineyard, with slope gradients ranging from 20 to 35%. The tests included forwarding the processed residue to a central storage place 3 km away. Harvesting–processing productivity ranged from 1.1 to 1.7 t per scheduled machine hour (SMH), including all delays. Calculated harvesting–processing costs varied between 19.7 and 32.3 € t−1, but increased from 53.0 and 105.2 € t−1 when forwarding the residues to a central collection point was included. The additional cost of residue management could amount to about 25 € t−1 (50 € ha−1 for 2 t ha−1). The commercial viability of recovering vineyard pruning residue also depends on the eventual redistribution of the savings accrued on residue management. The studied systems offered different products: systems 1 and 2 produced bales, which are easier to store, but are not suited for the feeding of automated furnaces, unless they are further processed into chips. However, systems 3 and 4 produced chips, which are more difficult to store but can be fed to automated furnaces without any further processing.

Relationships between site characteristics, farming system and biodiversity on Australian mixed farms

A collaborative project between researchers, regional natural resource management organisations and landholders set out to explore three questions about the relationships between biodiversity and land use in Australia’s mixed-farming landscapes: (1) the extent to which farm-scale measures of biodiversity were related to agricultural production; (2) the influence of the type and intensity of agricultural production on native biodiversity on farms; and (3) the relative influence of site and farming system on selected measures of biodiversity. Four land-use types on 47 mixed farms across nine regions, derived from several of Australia’s 56 natural resource management regions, were surveyed in autumn and spring 2006 and 2007. Surveys of birds, surface invertebrates (beetles, ants, spiders), vegetation and soils were undertaken on four land classes on each farm; crop, ‘rotation’ (break crop/pasture phase), perennial pasture and remnant vegetation. Data were collected by participating regional staff, using a standard protocol, which were sent to a central collection point for collation, analysis and interpretation. Species richness, functional diversity and vegetation structure were assessed. This introductory paper focuses on results relating to species richness, which for most taxa was greater in remnant vegetation than other land-use classes and declined along a disturbance gradient (remnant, pasture, rotation, crop). Properties with a greater proportion of perennial pastures recorded higher species richness than properties that were dominated by crop. Properties that recorded high wheat yields (t/ha) also recorded lower species richness for spiders and birds. The presence of insectivorous birds and beneficial invertebrates (spiders, beetles and ants) in all land-use classes suggests the potential to apply integrated pest management approaches to mixed-farming systems across the country. Site and system features were found to be important determinants of biodiversity, with their relative importance varying with the scale of investigation and the taxa. At the landscape scale, bird species richness was correlated with the amount of remnant vegetation within a 5-km radius of the farm boundary, and with the condition of native vegetation on the farm. The average size of remnant vegetation patches was 5 ha or less on nearly half of the properties surveyed. At the farm scale, ant species richness was correlated with site features, while beetles were correlated with management/system features such as the presence and fertility of perennial pastures. Analyses at the functional group level will provide more detailed information on relationships between different land-use types. Further experimental work needs to be undertaken to qualify the suggested impact of land management practices on different taxa, while repeated surveys will allow for the collation of datasets over time, from which population dynamics may be determined.

Advanced Metering Infrastructure: Lifeblood for Water Utilities

This article discusses advanced metering infrastructure (AMI), a metering system that records customer consumption hourly or more frequently, and provides for daily or more frequent transmittal of measurements over a communication network to a central collection point. The article describes the use of AMI in the energy (electric utilities) industry but focuses on its use in the water industry, demonstrating how the technology is ideal for the water industry challenges of managing growing water demand against shrinking supplies, higher operating costs, and reduced staff. Drivers behind the interest in AMI include: growing demand for systems that help reduce nonrevenue water losses and associated delivery costs, stem hidden water losses, support water conservation programs, manage peak loads, improve the integrity of delivery systems, and plan for future growth; curtailing water consumption during peak‐energy or drought‐induced restricted‐use periods; and, information management for water delivery and use. AMI benefits for the water industry are discussed, along with the five main components of an AMI system