Top PDF Review: visual analytics of climate networks

Review: visual analytics of climate networks

Review: visual analytics of climate networks

Climate network analysis has been successfully applied to investigate spatiotemporal climate variability and complex relationships within the climate system and has been shown to provide insights that complement commonly applied methods of eigen-analysis of climatological data (Donges et al., 2015b). Several stability-focused studies have found evidence that the ENSO phenomenon causes a weakening of spatial statistical interrelationships and thermal stability in the global climate system, as well as reduces predictability (Yamasaki et al., 2008; Tsonis and Swanson, 2008; Berezin et al., 2012). Climate networks have been used to uncover a backbone structure carrying a considerable amount of matter, energy, and dynamical information flow in the global surface air temperature field (Donges et al., 2009a, b) and to unravel subtle shifts in climate subsystems, e.g. a westward prop- agation of the Atlantic Multidecadal Oscillation (Feng and Dijkstra, 2014) or a stability change of the Atlantic Merid- ional Overturning Circulation (van der Mheen et al., 2013). In other studies, the spatial variation of extreme rainfall has been used to uncover typical moisture pathways and extreme rainfall propagation, as well as to investigate involved con- vergence zones (Malik et al., 2010, 2012; Rheinwalt et al., 2012; Boers et al., 2013, 2014). By introducing new concepts for irregularly sampled time series, palaeo-climate networks have been used to reveal changes of the influences of the Indian Summer Monsoon on the East Asian Summer Mon- soon during warm and cold periods (Rehfeld et al., 2012). Among the studies focusing on the El Niño–Southern Oscil- lation, teleconnections in general or atmospheric circulation patterns have been subject of interest – e.g. Rossby waves or the Walker circulation (Runge et al., 2012; Wang et al., 2013).
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Visual Analytics and knowledge creation from Big Data: A systematic review

Visual Analytics and knowledge creation from Big Data: A systematic review

One of the turning points to increase funding in Big Data is related to the 9-11 attacks, when the U.S. government saw the need and possibility of using great vol- umes of data to identify suspicious and dangerous individuals (FRIEDMAN, 2012). However, a big change started in 2005 with the beginning of Web 2.0, and after, when Yahoo! turned Hadoop in an open source technology, in 2008 (TARIFA, 2014). Meanwhile, the fast spread of mobile devices contributed to the exponential growth of data, bringing new needs and possibilities in analytics. Recently, the internet of things (IoT), self-driving cars and other technologies are incrementing this tendency of data growth, storage and analysis of these information.
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A concise review on multifaceted impacts of climate change on plant phenology

A concise review on multifaceted impacts of climate change on plant phenology

Crop production is particularly sensitive to climate change (Craufurd and Wheeler, 2009). Temperature is a major determinant of the rate of plant development and, under climate change; warmer temperatures that shorten development stages of determinate crops will most probably reduce the yield of a given variety. Earlier crop flowering and maturity have been observed and documented in recent decades, and these are often associated with warmer (spring) temperatures (Craufurd and Wheeler, 2009). For example, the yield of wheat declined by 5–8% (Wheeler et al., 1996; Craufurd and Wheeler, 2009) or 10% (Mitchell et al., 1993) per 1 0 C rise in mean seasonal temperature. The timing of anthesis and grain maturity was earlier at warmer temperatures in both studies, thus shortening the duration of growth and reducing grain yield (Craufurd and Wheeler, 2009). Earlier flowering and maturity have been observed and documented in crop plants (Williams et al., 2004; Hu et al., 2005; Menzel et al., 2006; Tao et al., 2006; Estrella et al., 2007), as well as in natural communities (Fitter and Fitter, 2002), over the last 50 years from phenology networks and individual records. Menzel et al., (2006), for example, report that 78% of all observations in 21 European countries showed earlier flowering, with an advance in phonological events of 2.5 d per decade on average (Craufurd and Wheeler, 2009).
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Targeting molecular networks for drug research

Targeting molecular networks for drug research

Physiological side effects can be caused by binding of drugs to proteins (“off-targets”), in addition to their intended targets. As side effects are crucial factors in therapeutic applications, their accurate prediction is of eminent importance to avoid failure in drug trials. Notably, systematic recording of side effects repre- sents a broad phenotying on the level of the human organism, providing valuable holistic information on the action of drugs. A unique resource, with this objective, is the SIDER database, which accumulates reported side effects for almost 1000 marketed drugs (Kuhn et al., 2010). Using this database, Mizutani et al. (2012) correlated a drug’s side effects with the proteins it binds to. For this, side effects and bound proteins were represented as binary profiles and statistically associated using a modified ver- sion of canonical correlation analysis. The obtained correlation was used subsequently for the prediction of side effects, by evalu- ating the proteins that the drug binds to. Remarkably, it is equally possible to predict a drug’s target based on its side effects. This relationship was originally explored by Campillos et al. (2008); they identified new targets of known drugs based on the sim- ilarity of their side effects with those of other drugs. There is now a database, which has implemented this approach, called PROMISCUOUS (von Eichborn et al., 2011). It enables the inter- active exploration of an integrated network of drug, protein, and side effect nodes, and can be used to gain new insight into the drug’s mode of action. Finally, side effects can also be indica- tive for drug–drug interactions, which are frequently of clinical relevance. It was recently shown that two drugs tend to inter- act, if their targets are in close proximity in a PPI network, or if they have similar side effects (Huang et al., 2013). Moreover, combining information on physical interaction of drug targets and recorded side effects improves the prediction accuracy for drug–drug interactions.
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Cad. Saúde Pública  vol.31 número1

Cad. Saúde Pública vol.31 número1

The reviewers disagreed on 3 of the 11 items; this disagreement was resolved by consensus. The presence of withdrawals from the sample was not clarified in all studies; additionally, it was not possible to determine whether data interpre- tation was conducted in a blinded manner in the included studies. Fifty percent of the studies did not describe whether the clinical information available was that used in clinical practice, and the remainder showed bias on that item. Addi- tionally, 25% of the studies did not provide suf- ficient information to enable an assessment of whether the sample was representative, that is, whether they considered the patients receiving routine tests.
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A Review of Interference Reduction in Wireless Networks Using Graph Coloring Methods

A Review of Interference Reduction in Wireless Networks Using Graph Coloring Methods

If a network incurs a large interference, either many communication signals sent by nodes will collide, or the network may experience a serious delay at delivering the data for some nodes, and even consume more energy. So, we reach to the conclusion that the interference is a major drawback of wireless networks. The aim of reducing interference is to prevent adjacent or connected nodes, which are linked by radio signals, from receiving and transmitting signals which conflict or blend together. Thus, interference occurs when conflicting transmissions over one radio frequency are received by one or more nodes in a wireless network. This inhibits the ability of the receiver to decipher incoming signals. This concept is illustrated in Figure 1a, which shows a typical situation in which the broadcast areas of nodes A and C overlap in the vicinity of node B, causing B to receive a garbled signal composed of the signals from A and C. In such situations, it is difficult for B not only to decipher simultaneous signals, but also to reliably determine the source of the signal. The problem of reducing interference in arbitrary networks turns out to be very difficult, and for this reason, simpler network layouts have been investigated such as, multi-hop wireless mesh network layouts [1], triangular lattice topologies [9], unit disk graphs [3], hexagonal topologies [8], and other more general topologies [4]. Other key facets of the interference problem in wireless networks specify whether a proposed solution is contrived in a distributed or centralized setting, whether nodes in a given solution are self- aware of their location or whether this assumption is not necessary, and whether or not minimum separation distance between nodes needs to be factored into algorithmic solutions.
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Ciênc. saúde coletiva  vol.14 número6

Ciênc. saúde coletiva vol.14 número6

tries when precursor emissions are held constant, leading to increased m orbidity and m ortality. There is less certainty of the possible impact of climate change on fine particulate concentrations. More stringent em issions controls for ozone, PM2.5, and other pollutants can be expected with the growin g body of eviden ce of the adverse health impacts of these air pollutants. Therefore, the extent to which climate change affects air qual- ity will depend partially on ongoing regulatory control of ozone and PM2.5. At the same time, population sensitivity m ay change because of medical advances and changes in risk factors. The main public health responses to the projected health impacts of climate change are mitigation and adaptation. Adaptation is not an effective risk management strategy for poor air quality, because physiologic mechanisms to decrease sus- ceptibility to ozone and other air pollutants are limited. Therefore, if improved model experi- ments continue to project higher ozone concen- trations under a changing climate, rapid reduc- tions of emissions from fossil- fuel burning are needed to protect the health of current and fu- ture generations. Evidence suggests that reduc- ing current tropospheric ozone concentrations reduces morbidity and mortality, with significant savings in medical care costs 106 . For relevant agen-
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Review on Vertical Handover Techniques among Heterogeneous Networks

Review on Vertical Handover Techniques among Heterogeneous Networks

G rowing consumer demand for access to communication services anywhere and anytime is accelerating the technological development towards the integration of various wireless access technologies, nowadays called as Fourth Generation (4G) wireless systems. 4G wireless systems will provide significantly higher data rates, offer a variety of services and applications previously not possible due to speed limitations, and allow global roaming among a diverse range of mobile access networks. In a typical 4G networking scenario, handsets or mobile terminals with multiple interfaces will be able to choose the most appropriate access link among the available alternatives (these include IEEE 802.11 Wireless Local Area Network (WLAN), Future network devices will need to roam seamlessly across heterogeneous access technologies such as 802.l1, WiMAX, CDMA, and GSM, between wired networks such as xDSL and cable, as well as between packet switched and circuit switched (PSTN) networks.
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Knowledge analytics

Knowledge analytics

For Maisis, the main motivation behind this master work is to add value to the Oobian plat- form. In the economical context of today, with a very competitive market, companies have to innovate and answer with quality products to the client’s needs. There is a growing need on the field of business analytics for tools that provide features to create reports about big collections of data. The Oobian platform is a horizontal knowledge management platform that provides better search and navigation through knowledge. Oobian extracts and indexes information from non-structured and structured data scattered inside and outside the organ- isation, transforming it into real business knowledge. One of the gaps that were identified is the lack of business analytics features in the platform. This feature could potentially improve the business intelligence processes capabilities.
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Assessing the costs of hazards mitigation in the urban structure

Assessing the costs of hazards mitigation in the urban structure

The paper has explored the economic aspects of risk mitigation. The roles of game theory, agent based modelling and networks and urban public policies in designing decision systems for risk management were also discussed. The urban scale at which a natural hazard can impact leads to the importance of urban planning strategy in risk management. However, usually environmental engineering and social sciences deal with it, and the role of architecture and urban planning is neglected. ICT can contribute to organize the information from the building survey, for example, through taxonomy and ontology, to economic computations in direct modelling at urban or building scale or through translation of games’ rules and thus facilitate decision making. Games rules are at the same time supported by our field and archive studies, as well as research by design. We also take into consideration a rare element, which is the role of landscape planning through the inclusion of green elements in reconstruction after the natural and man-made disasters or in reconstruction efforts to mitigate climate change. Apart from existing old city fabric, also landscape can be endangered by speculation and therefore it is vital to highlight its high economic value, also in this particular case. As ICOMOS highlights for the 2014 congress, heritage and landscape are two sides of the same coin. Landscape may become or can be connected to a community centre, the first being necessary for building a settlement, the second raising its value, or it can build connections between landmarks in urban routes. For this reason, location plays a role not only for mitigating the effects of hazards, but also for increasing the value of land through vicinities. Games are only another way to build a model of the complex system, which is the urban organism in this regard; a model is easier to be analysed than the system while displaying its basic rules. The role of landscape of building roads of memory between landmarks in the reconstruction is yet to be investigated in a future proposed COST action.
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Climate change and epidemiology of human parasitoses in Saudi Arabia: A review

Climate change and epidemiology of human parasitoses in Saudi Arabia: A review

Human exposure to water-borne parasitoses occurs through drinking water, recreational water or food. Water contamination may result from either human actions or natural events. Rainfall can influence the propagation of the infective stage of this group of parasites while temperature affects their growth and survival in the external environment. Outbreaks of water-borne parasitoses often occur after severe precipitation events. Heavy precipitation and its subsequent runoff have been assumed to be a major factor in the transmission of water-borne parasitic infections [140] . Many parasites can be transmitted via contaminated water, but only Cryptosporidium, Cyclospora, Giardia and Toxoplasma are difficult to be destroyed in drinking water by conventional disinfection methods [141-144] . Rainfall and runoff have been incriminated in many outbreaks of water-borne parasitoses in the UK and the US [145-150] . Because climate change is anticipated to enhance the severity and frequency of some major precipitation events in Saudi Arabia, the country could be faced with the elevated burden of water-borne diseases. Unfortunately, cryptosporidiasis, cyclosporiasis, giardiasis and toxoplasmosis are not uncommon in Saudi Arabia and the water- borne transmission of these diseases through drinking water is possible [119,151-156] .
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A review of wave climate and prediction along the Spanish Mediterranean coast

A review of wave climate and prediction along the Spanish Mediterranean coast

from a single population (homogeneity), no climate change trends are present and the events are independent. For the definition of an independent storm event it is necessary a cri- terium of minimum significant wave height, interval without data, period with data below the minimum significant wave height and minimum duration. To derive an extreme sam- ple the peaks over a threshold (POT), separated by four days or more (to achieve a certain degree of statistical indepen- dence), have been selected. The criteria to define a storm sample have, thus, been i) the distance between storm (con- secutive) down-crossing and up-crossing being larger than four days, ii) the eventual periods below the threshold level being smaller than six hours. For the strongest events their association to a single low-pressure centre was also consid- ered. The resulting sample showed a differential behaviour in terms of wave height and wave period and storm duration when considering the main three sectors of wave incidence (East, South and North-West). This suggest a directional- based analysis to improve the homogeneity of the resulting sub-samples. This exercise could not be completed with the available time series due to the small number of storms left in each directional sector.
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How emissions, climate, and land use change will impact mid-century air quality over the United States: a focus on effects at national parks

How emissions, climate, and land use change will impact mid-century air quality over the United States: a focus on effects at national parks

Future regional visibility may also be impaired by fire pol- lution resulting from climate change. We find that fire pollu- tion may maintain visibility levels at present-day conditions during the most polluted events in some NPs and wilderness areas (e.g., Crater Lake NP; Fig. 9b) or may impede the at- tainment of the 2050 visibility target (e.g., Yellowstone NP; not shown). Our analysis shows little or no effect of fire in visibility impairment in NPs and wilderness areas located in the Northeast and Southeast climatic regions (e.g., Acadia NP; Fig. 9b). Yue et al. (2013) estimate that future fire ac- tivity would lead to an average visibility decrease of 30 km in the 32 Federal Class I areas located in Rocky Mountains Forest. Our predictions for the Rocky Mountain NP show more moderate decreases in visibility (4–6 km; not shown). However, our work differs from Yue et al. (2013) in both the model resolution (200 vs. 400 km) and the spatial distribution of the fire emissions.
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Par@Graph – a parallel toolbox for the construction and analysis of large complex climate networks

Par@Graph – a parallel toolbox for the construction and analysis of large complex climate networks

The availability of Par@Graph will allow to solve a new set of questions in climate research one of which, the coherence of the ocean circulation at different scales, was shortly discussed in this paper. Apart from higher resolution data sets of one observ- able, it will now also be possible to deal with data sets of several variables and to more efficiently reconstruct and analyze networks of networks (Berezin et al., 2012). How-

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A Review on - Comparative Study of Issues in Cellular, Sensor and Adhoc Networks

A Review on - Comparative Study of Issues in Cellular, Sensor and Adhoc Networks

A wireless adhoc network is a decentralized type of wireless network. The network is adhoc because it does not depend on a preexisting infrastructure, such as routers in wired networks or access points in managed, infrastructure wireless networks. Instead, each node participates in routing by forwarding data for other nodes, and so the determination of which nodes forward data is made dynamically based on the network connectivity. A Mobile Adhoc Network (MANET) is an autonomous collection of mobile routers and associated hosts connected by bandwidth- constrained wireless links. Each node is viewed as a personal information appliance such as a personal digital assistant (PDA) fitted out with a fairly sophisticated radio transceiver. The nodes are fully mobile.
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Review on Using Packages to Enhance the Teaching of Critical Path Networks

Review on Using Packages to Enhance the Teaching of Critical Path Networks

In costing and crashing, Excel can do the work very well but the programming technique involved is difficult even for engineering students. Students must have a very good grasp of the concept of objective 6 (crashing) before they can program the package. This is good in the sense that students have to learn the underlying principles and do not rely on software packages to obtain the results. However, POM- QM for Windows 3 is more suitable for beginners as it will be able to do crashing on an activity level but may not be so practical for practitioners. MS Project 2007 is more practical as it can compare costs with changing inputs like normal and overtime hourly rates. It can cope with change at resource level and is nearer to a real life situation. Both can meet the requirements of objective 6 of the module; this matches the desired outcome as students can evaluate the most economic and/or the shortest possible time based on the information provided. Both packages, MS Project 2007 and POM-QM for Windows 3, can perform the functions but POM-QM for Windows 3 is better because it shows the critical path in the Gantt chart without requiring further operation. Again, both packages can satisfy objective 6 of the module; this matches the desired outcome as students can construct Gantt chart quickly and logically.
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SECURITISATION OF CLIMATE CHANGE: THE RISK OF EXAGGERATION

SECURITISATION OF CLIMATE CHANGE: THE RISK OF EXAGGERATION

But these emerging countries are precisely those who have overtly rejected the security narrative on climate change. In the UN Security Council debates on climate change of both 2007 and 2011, leading developing countries criticised the move to discuss climate change in the Security Council and expressed great scepticism regarding alarmist security framings on climate change. To counter the security discourse on climate change, the Brazilian delegation for instance argued: ‘...utmost caution must be exercised in esta- blishing links between conflict and the utilization of natural resources or the evolution of climate on our planet (UNSC, 2007: 20)’. Similar sceptical comments were made by other emerging developing countries, such as China and India, and has been supported by other developing countries who see climate change as a matter of sustainable deve- lopment (Sindico, 2007). In particular, emerging developing countries with no special voting powers in the UN Security Council – such as India and Brazil – have been highly sceptical of these moves and thus prefer climate change to be discussed in forums where they do have decision-making power. In the 2011 debate, a number of emerging countries that were generally sceptical of a security framing of climate change - China, Russia, Brazil and India - were considerate of the precarious situation of developing small island states (SIDS). Brazil, for one, commented that the ‘rather indirect relationship between security and climate change in no way diminishes the urgency of supporting countries and populations that are most vulnerable to climate change, in particular small island developing States, many of which face truly existential challenges’ (UNSC 2011: 8). The emerging developing countries however accused the West of intending to change the terms of the debate by making climate change a subject of the UN Security Council, risking the further polarisation of the climate debate.In addition to these problems, the alarmist climate security narrative was also unable to maintain support within the UK itself in recent years. The tide has changed somewhat since the Coalition Government came into power in 2010 and the promotion of climate action in the UNFCCC was given a lower level of priority. In the 2010 National Security Strategy and the 2010 Strategic Defence and Security Review produced in the time of the Coalition Government, the need for a multilateral deal on climate change mitigation is only mentioned once (Cabi- net Office, 2010: 18), and a security narrative had not been employed to promote efforts towards such action. The policy constituency within the UK fizzled out, making space for alternative and related framings (Boas and Rothe 2016).
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AHK Rio de Janeiro : in search of communication satisfaction : the CSQ Technique

AHK Rio de Janeiro : in search of communication satisfaction : the CSQ Technique

Communication is crucial for the management of every organization. An understanding of the efficiency of an established communication strategy is vital to attain high levels of organizational effectiveness. With this in mind, many companies use communication audits to identify strategies to improve their communication practices. The specific subject of this thesis is to examine the communication within organizations and its relations to job and customer satisfaction. The research part of this thesis contains a case study about the German-Brazilian Chamber of Commerce Rio de Janeiro (AHK-RJ). The aim of this paper is to answer the question: “How efficient is the current internal communication of the AHK-RJ measured by job satisfaction? And “How efficient is the external communication measured by the membership satisfaction of the AHK-RJ?” In order to answer those question, four research questions where developed. The research part was accomplished using quantitative research methods. By conducting an internal and external communication satisfaction questionnaire (CSQ), the effectiveness of the communication strategy of the AHK-RJ could be assessed. The two questionnaires consisted of a number of multiple choice questions as well as open ended questions, designed in accordance to the format of the CSQ developed by C.W. Downs and Hazen 1977. The primary result indicates that employees and members perceive satisfaction towards many specific issues. Nevertheless, opportunities for improvements are revealed. The overall communication evaluated by members is satisfying. In contrast employees are dissatisfied with the communication strategy of the AHK-RJ. Especially, the most important tool to receive information, the weekly team meeting is evaluated as unsatisfying. Hence, information flow and process adaptations are required. Challenging last month and major important happenings in Rio de Janeiro affected the team work and working environment, employee turn overs, a lack of trust and information and the multicultural background complicates the task of successfully implementing one integrated communication strategy. By communicating more strategically, providing more information from the top, and encouraging supervisors to provide more feedback and trainings, the AHK can create an even better workplace and higher employee satisfaction can be reached. This improvement of the internal communication strategy influences positively the satisfaction rates concerning the external communication and information exchange.
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Groundwater resources in Brazil: a review of possible impacts caused by climate change

Groundwater resources in Brazil: a review of possible impacts caused by climate change

However, the great importance of its resources for the social and economic development of the population contrasts with the lack of awareness of the potential and the stage of exploitation of the aquifers in the country, making it a great challenge for adequate water management. There are particularly no specific studies about the impact of climate change on aquifers, both on their recharge and on pressures associated to their increase in demand. This situation is worsened by the fact that the knowledge on the real potential of this resource is not complete and does not extend all over the country to allow a good resource management. Due to this situation, the purpose of this work is to evaluate, in a preliminar and regional scale, the potential impacts that are expected because of the climate change on aquifers, indicating, above all, regions where systematic analyses are necessary to reduce these impacts.
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Distinguishing the effects of internal and forced atmospheric variability in climate networks

Distinguishing the effects of internal and forced atmospheric variability in climate networks

Zealand because it shows a relatively high forced density (seen in Fig. 5a, b) and it is connected to the selected point over the tropical Pacific of Fig. 9a, b. Figure 11a shows connectivity between the chosen point and the Pacific and Indian oceans, as well as wave patterns (probably a Rossby wave train) along the extratropics. Figure 11b adds informa- tion to Fig. 11a, showing that these teleconnections are of in- terannual type. If we remove NINO3.4 (Fig. 11c, d) not sur- prisingly the links to the tropical Pacific disappear, but also some of the connectivity to the Indian Ocean, suggesting that part of the links with the Indian Ocean are indirect. Never- theless, the extra-tropical wave train remains, and Fig. 11d suggests that the wave train may be forced by the Indian Ocean at interannual timescales. As in the previous figure, some weak north–south teleconnections are found, but they disappear if we remove the NINO3.4 index, indicating again an indirect connection between the extratropics through the Pacific Ocean.
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