Conversion Scenarios Research Articles

Students’ perception of the prognosis for a single‐surface amalgam restoration

The aim of the study was to assess the self-rated skill, clinical judgement and competency of final-year pre-doctoral dental students. The study was also designed to determine whether the students' estimated durability of their single-surface restorations was determined by their confidence. Students were given a questionnaire and completed it anonymously. One hundred and ninety-six forms were returned from the 238 students (82% return rate). Complete analysis was possible on 169 questionnaires. The students' self-assessed skill and judgement were a significant factor in predicting how long they would tell a patient that their restoration would last. Those ranking themselves below average were more likely to state that their amalgam restorations would have a shorter life (odds increased by 2.82 for those ranking themselves lower than most others). There was a significant association between the students' self-assessed skill and judgement and their confidence in dealing with both the initial management of patients' medical emergencies (ρ = 0.244, P = 0.001, n = 191) and their general confidence in dealing with medical emergencies (ρ = 0.187, P = 0.01, n = 188). Given a conversational scenario with a patient, the treatment prognosis given by final-year pre-doctoral students for a single-surface amalgam restoration was dependent on their self-assessed competence, skill and judgement.

Plasma and antenna coupling characterization in ICRF-wall conditioning experiments

Ion Cyclotron Wall Conditioning (ICWC) discharges, in pulsed-mode operation, were carried out in the divertor tokamaks ASDEX Upgrade (AUG) and JET to simulate the scenario of ITER wall conditioning at half-field (AUG) and full-field (JET). ICWC-plasma and antenna coupling characterization results obtained during the Ion Cyclotron Resonance Frequency (ICRF)-Wall Conditioning experiments performed in helium-hydrogen mixture in AUG and helium-deuterium mixtures in JET are presented here. Safe operational regimes for optimum ICWC in ITER could be explored for different magnetic fields. Satisfactory antenna coupling in the Mode Conversion scenario along with reproducible generation of ICRF plasmas and reliable wall conditioning were achieved by coupling RF power from one or two ICRF antennas at two (AUG, JET) different resonant frequencies. These results are in qualitative agreement with the predictions of 1-D TOMCAT code. Present study of ICWC indicates towards the beneficial effect of application of an additional (along with toroidal magnetic field) stationary vertical (BV≪BT) magnetic field on antenna coupling and plasma parameters. The results obtained from JET and AUG tokamaks, presented in this paper, emphasizes the proposed phenomenological schemes for further development of ICWC in superconducting tokamaks.

Modelling selective visual attention for autonomous virtual characters

ABSTRACTAutonomous virtual characters (AVCs) are becoming more prevalent both for real‐time interaction and also as digital actors in film and TV production. AVCs require believable virtual human animations, accompanied by natural attention generation, and thus the software that controls the AVCs needs to model when and how to interact with the objects and other characters that exist in the virtual environment. This paper models automatic attention behaviour using a saliency model that generates plausible targets for combined gaze and head motions. The model was compared with the default behaviour of the Second Life (SL) system in an object observation scenario while it was compared with real actors' behaviour in a conversation scenario. Results from a study run within the SL system demonstrate a promising attention model that is not just believable and realistic but also adaptable to varying task, without any prior knowledge of the virtual scene. Copyright © 2011 John Wiley & Sons, Ltd.

Empathy-Based Emotional Alignment for a Virtual Human: A Three-Step Approach

Allowing virtual humans to align to others’ perceived emotions is believed to enhance their cooperative and communicative social skills. In our work, emotional alignment is realized by endowing a virtual human with the ability to empathize. Recent research shows that humans empathize with each other to different degrees depending on several factors including, among others, their mood, their personality, and their social relationships. Although providing virtual humans with features like affect, personality, and the ability to build social relationships, little attention has been devoted to the role of such features as factors modulating their empathic behavior. Supported by psychological models of empathy, we propose an approach to model empathy for the virtual human EMMA—an Empathic MultiModal Agent—consisting of three processing steps: First, the Empathy Mechanism by which an empathic emotion is produced. Second, the Empathy Modulation by which the empathic emotion is modulated. Third, the Expression of Empathy by which EMMA’s multiple modalities are triggered through the modulated empathic emotion. The proposed model of empathy is illustrated in a conversational agent scenario involving the virtual humans MAX and EMMA.

Simulated watershed mercury and nitrate flux responses to multiple land cover conversion scenarios

Water quality and toxic exposure science is transitioning towards analysis of multiple stressors rather than one particular environmental concern (e.g., mercury) or a group of similarly reacting chemicals (e.g., nutrients). However, two of the most important water quality constituents affecting both human and ecosystem health today, reactive nitrogen (N(r) ) and methylmercury (MeHg), are often assessed separately for their independent effects on water quality. With the continued pressure of landscape modifications on water quality, a challenge remains in understanding the concurrent watershed flux response of both N(r) and MeHg to such physical stressors, particularly at the spatial scale (regional watersheds) and within the mixed land cover type systems that most decision-making processes are conducted. We simulate the annual average and monthly flux responses of Hg (MeHg and total mercury [HgT]), NO(3) -N, and runoff to four land cover change scenarios in the Haw River Watershed (NC, USA), a headwater system in the Cape Fear River Basin. Fluxes are simulated using a process-based, spatially explicit watershed Grid-Based Mercury Model (GBMM) and a NO(3) -N watershed flux model we developed to link to GBMM. Results suggest that annual NO(3) -N and Hg fluxes increase and decrease concomitantly to land cover change; however, the magnitude of the changes in NO(3) -N, MeHg, HgT, and water fluxes vary considerably between different land cover conversion scenarios. Converting pasture land to a suburbanized landscape elicited the greatest increase in runoff and MeHg, HgT, and NO(3) -N fluxes among all four conversion scenarios. Our findings provide insight for multi-stressor ecological exposure research and management of coastal eutrophication resulting from elevated N(r) loadings and exposure risk due to elevated concentrations of MeHg in fish tissue.

Dynamic Simulation of the Electron Bernstein Wave Heating Under NBI Conditions in TJ–II Plasmas

AbstractIn this work, we have calculated the expected properties of the Electron Bernstein Wave (EBW) heating using the O–X–B double mode conversion scenario in a plasma that evolves from Electron Cyclotron Resonance (ECR) to Neutral Beam Injection (NBI) heating in the TJ–II device. For this purpose, a transport simulation that reproduces the time evolution of a typical collapsing plasma heated by a combination of ECR and NBI power has been used. It is seen that the predicted EBW absorption depends strongly on the plasma characteristics, whose time evolution depends in turn on the heating properties. Therefore, the need of consistently computing the ray tracing and the plasma evolution is underlined. The fraction of the absorbed EBW heating power becomes very high as soon as the O mode cutoff layer appears. This guarantees the overlapping of both EBW and ECR heating, thus avoiding excessive plasma cooling when the wave cutoff is reached. The EBW power deposition profile evolves from off‐axis to a much more centred shape that persists until the radiative collapse quenches the plasma (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Dynamic modeling of forest conversion: Simulation of past and future scenarios of rural activities expansion in the fringes of the Xingu National Park, Brazilian Amazon

The present work is committed to simulate the expansion of agricultural and cattle raising activities within a watershed located in the fringes of the Xingu National Park, Brazilian Amazon. A spatially explicit dynamic model of land cover and land use change was used to provide both past and future scenarios of forest conversion into such rural activities, aiming to identify the role of driving forces of change in the study area. The employed modeling platform – Dinamica EGO – consists in a cellular automata environment that embodies neighborhood-based transition algorithms and spatial feedback approaches in a stochastic multi-step simulation framework. Biophysical variables and legal restrictions drove this simulation model, and statistical validation tests were then conducted for the generated past simulations (from 2000 to 2005), by means of multiple resolution fitting methods. Based on optimal calibration of past simulations, future scenarios were conceived, so as to figure out trends and spatial patterns of forest conversion in the study area for the year 2015. In all simulated scenarios, pasturelands remained nearly stable throughout the analyzed period, while a large expansion in croplands took place. The most optimistic scenario indicates that more than 50% of the natural forest will be replaced by either cropland or pastureland by 2015. This modeling experiment revealed the suitability of the adopted model to simulate processes of forest conversion. It also indicates its possible further applicability in generating simulations of deforestation for areas with expanding rural activities in the Amazon and in tropical forests worldwide.

Jaguar Land Rover “transition to high performance” training program

PurposeThe purpose of this paper is to describe a training program that was specifically designed to underpin the launch of a new behavior framework and performance management process, required to support the pace of organizational change in the face of increasingly competitive market demands.Design/methodology/approachThe core focus of the training program was on practical skills acquisition reinforced by role‐play, using performance management conversation scenarios designed to reflect the daily business context of the participants – therefore enabling direct transfer of skills back to the workplace. The impact of the training program was greatly enhanced by allowing participants to practice the techniques being taught, before attempting to apply them in their performance management conversations with their respective team members.FindingsThe training program resulted in the successful launch of the new behavior framework and performance management process, and engagement of the management population in applying the new process consistently: with a significant increase in evidence‐based assessment and an associated willingness by the participants to conduct appropriate difficult performance‐related conversations in their line management roles.Originality/valueThe design and methodology of this performance management training program will be of value to a wide range of organizations across all business sectors seeking to implement a behavior framework‐based performance management process; and needing to increase the skills and effectiveness of line managers in addressing performance issues in their respective teams.

Comparison of different models for EBCD calculation in the TJ-II Stellarator

In this work, we have compared different linear methods to estimate the electron Bernstein current drive (EBCD). The expressions for the current drive efficiency have been plugged into the ray tracing code TRUBA, which was used in previous works for electron Bernstein wave (EBW) heating studies in the TJ-II stellarator. This device is taken here as an example for this comparison.The driven current is calculated for different densities and temperatures, as well as launching directions of the heating beam, which is a critical issue in the O–X–B mode conversion scenario considered in TJ-II. The range of applicability of each model is discussed. The influence of the Ohkawa, relativistic and frictional trapping effects on the total current generated is studied by comparing the results obtained by pairs of models that include and neglect those effects. The Ohkawa effect has resulted in being the least important. Although the relativistic effects are not negligible, the main disagreement between the results arises from including or not momentum conservation and neglecting frictional trapping effects. The total EBCD current drive efficiency calculated is in all cases greater than the experimental ECCD one, previously measured in TJ-II. The results presented in this work are the guideline for future experiments in this device.

Hazards to Family Relationships from Cell Phone Usage While Driving

The focus of the literature on the problems of cell phone use while driving has been on how driving is more risky while talking on a cell phone, but there are reasons to think that cell phone usage while driving is also risky to the relationships of the parties involved in the phone conversation. The same factors that make driving more risky while using a cell phone (for example, longer reaction times and impaired attention) can also make family communication in that situation more risky. This article provides a speculative theoretical analysis applying cognitive models of the effects of divided attention and distracted communication to suggest why cell phone communication when one of the family members in the conversation is driving can be risky. The analysis is applied to five hypothetical family conversation scenarios that could create difficulties.

Food waste conversion options in Singapore: Environmental impacts based on an LCA perspective

Proper management and recycling of huge volumes of food waste is one of the challenges faced by Singapore. Semakau island — the only offshore landfill of the nation — only accepts inert, inorganic solid waste and therefore a large bulk of food waste is directed to incinerators. A remaining small percent is sent for recycling via anaerobic digestion (AD), followed by composting of the digestate material. This article investigates the environmental performance of four food waste conversion scenarios — based on a life cycle assessment perspective — taking into account air emissions, useful energy from the incinerators and AD process, as well as carbon dioxide mitigation from the compost products derived from the digestate material and a proposed aerobic composting system. The life cycle impact results were generated for global warming, acidification, eutrophication, photochemical oxidation and energy use. The total normalized results showed that a small-scale proposed aerobic composting system is more environmentally favorable than incinerators, but less ideal compared to the AD process. By making full use of the AD's Recycling Phase II process alone, the Singapore Green Plan's 2012 aim to increase the recycling of food waste to 30% can easily be achieved, along with reduced global warming impacts.

Biofuel production potentials in Europe: Sustainable use of cultivated land and pastures, Part II: Land use scenarios

Europe's agricultural land (including Ukraine) comprise of 164 million hectares of cultivated land and 76 million hectares of permanent pasture. A “food first” paradigm was applied in the estimations of land potentially available for the production of biofuel feedstocks, without putting at risk food supply or nature conservation. Three land conversion scenarios were formulated: (i) A base scenario, that reflects developments under current policy settings and respects current trends in nature conservation and organic farming practices, by assuming moderate overall yield increases; (ii) an environment oriented scenario with higher emphasis on sustainable farming practices and maintenance of biodiversity; and (iii) an energy oriented scenario considering more substantial land use conversions including the use of pasture land. By 2030 some 44–53 million hectares of cultivated land could be used for bioenergy feedstock production. The energy oriented scenario includes an extra 19 million hectares pasture land for feedstocks for second-generation biofuel production chains. Available land is foremost to be found in Eastern Europe, where substantial cultivated areas can be freed up through sustainable gains in yield in the food and feed sector. Agricultural residues of food and feed crops may provide an additional source for biofuel production. When assuming that up to 50% of crop residues can be used without risks for agricultural sustainability, we estimate that up to 246 Mt agricultural residues could be available for biofuel production, comparable to feedstock plantations of some 15–20 million hectares.

Integration of a small biofuel refinery in a rural context

In this work three scenarios of biomass production, conversion and utilization of different biofuels (sunflower crude oil, sunflower refined oil and sunflower methyl-ester) in a rural context are compared. The analysis is referred to the district of Pisa, in Italy. Technical feasibility was analysed by comparing process schemes and safety issues, while environmental impacts were studied by applying the methodology of life cycle assessment. Scenarios involving upgrading of crude sunflower oil (refined oil and biodiesel) require complex plants and the management of dangerous materials, and they produce considerable amounts of wastewater. These scenarios need larger plant size, more complex organization (farm cooperatives) and higher costs than the simple mechanical operations associated with crude oil production. On the other hand the use of low-quality fuels in internal combustion engines can lead to short engine lifetime and high pollutant emissions. The life cycle analysis shows that the biofuel upgrading processes (refining and transesterification) and oil transport have a low influence on the environmental impact, compared to seed cultivation, which is the most impacting step. However fuel upgrading allows a significant reduction in polluting emission during combustion; as a consequence biodiesel results the most sustainable biofuel.

Analysis of Voice Change During Cellular Phone Use: A Blinded Controlled Study

It is a growing belief that cellular phone use may be hazardous to the voice. This study aims to assess voice production in different conversational scenarios to identify any changes in vocal production that may be specific to cellular phone use. Twenty healthy participants were randomized to seven conversational scenarios: quiet conditions face to face; quiet conditions over a landline; quiet conditions using a cellular phone (QCP); quiet conditions using cellular phone with earpiece (QCPE); noisy conditions face to face (NFF); noisy conditions using cellular phone (NCP); and noisy conditions using cellular phone with earpiece (NCPE). In each condition, participants performed spontaneous speech, a standardized reading passage, and sustained voicing. Sound pressure levels (dB SPL) and fundamental frequencies (F(0)[Hz]) were measured. Subjects completed a 100-mm visual analog scale measuring vocal effort after each speaking scenario. Statistical analysis was performed using analysis of variance (ANOVA). There was a significant difference in dB SPL and F(0) between all quiet conditions relative to all noisy conditions (P<0.001). There was no difference in cellular phone use relative to any other conversational condition in mean dB SPL, respective of ambient noise. Vocal effort was rated greater for noisy conditions compared with quiet conditions. Cellular phone use does not lead to a significant change in voice production relative to other speaking conditions. Voice problems associated with cellular phone use may simply be a function of the increased amount of voice use and increased vocal loudness (Lombard effect) associated with speaking in noisy situations rather than a variable inherent to the phone.

Food or fuel? What European farmers can contribute to Europe's transport energy requirements and the Doha Round

Farm support in higher income countries is a testament to the fundamental social and economic importance of agriculture, yet domestic efforts to support this sector can arouse multilateral discord in a world of global food markets. In this paper, we argue that the advent of biofuels offers a new opportunity for agriculture to contribute to society, and to do so in a way that reduces trade rivalry and improves energy security. Holding current agricultural production constant, we find that the EU has the potential to reduce oil imports between 6% and 28% by converting eligible agricultural crops into biofuels under two differing conversion scenarios. Further, 33% of food support could be removed with no net farm revenue loss, using the biofuel premia (compared with food value) of corn and rapeseed to compensate for subsidy reductions. These results can help overcome the current impasse in global trade negotiations by reconciling the needs of EU farmers with those who would gain from more liberal international trade.

Projected mature technology scenarios for conversion of cellulosic biomass to ethanol with coproduction thermochemical fuels, power, and/or animal feed protein

AbstractSeven process designs for producing ethanol and several coproducts from switchgrass are evaluated: four involving combinations of ethanol, thermochemical fuels (including Fischer‐Tropsch liquids, hydrogen, and methane) and/or power, and three coproducing animal feed protein. Material and energy balances – resulting from detailed Aspen Plus models – are reported and used to estimate processing costs and perform discounted cash flow analysis to assess plant profitability. In these mature technology designs, fossil fuel displacement is decidedly positive and production costs competitive with gasoline. © 2009 Society of Chemical Industry and John Wiley &amp; Sons, Ltd

Nutrient cycling in two continuous cover scenarios for forest conversion of pine plantations on sandy soil. I. Nutrient cycling via aboveground tree biomass

Conversion of coniferous pine plantations into mixed-species forests on sandy soils is an important concern for forest and nature management in Europe. However, little is know of the effect of the applied sylvicultural strategy on biogeochemical cycling throughout the conversion process. This study examined the aboveground biomass production and nutrient (N, P, K, Ca, and Mg) cycling in terms of litterfall, immobilization in stems and branches, canopy exchange, and yearly root uptake in two scenarios of continuous cover forestry a decade after the first intervention for converting a homogeneous Scots pine (Pinus sylvestris L.) forest. Four regeneration types were studied: silver birch (Betula pendula L.) and pine after a shelterwood cutting and birch and pine after a group cutting. In conclusion, it can be stated that both the tree species and the conversion scenario influence the circulation of nutrients through the forest ecosystem: cycling of N, P, and K is determined by the tree species as well as the conversion scenario, whereas circulation of Ca and Mg is predominantly influenced by the type of conversion.

Nutrient cycling in two continuous cover scenarios for forest conversion of pine plantations on sandy soil. II. Nutrient cycling via throughfall deposition and seepage flux

This study examined ion throughfall deposition and seepage fluxes in silver birch (Betula pendula L.) and Scots pine (Pinus sylvestris L.) regenerations a decade after a forest conversion intervention in two continuous cover scenarios (shelterwood cut versus group cut), as well as a 70-year-old control stand of Scots pine. Ion throughfall deposition was significantly influenced by the conversion scenario, being higher in the shelterwood cut than in the group cut. Compared with the control stand, nitrogen and acidifying throughfall deposition was significantly lower (–60%) in all regeneration types except for the birch regeneration under shelter. After shelter removal, ion throughfall deposition was significantly lower in all regeneration types than in the control stand. Seepage of NO3– and SO42– was significantly affected by the tree species, being higher in the birch than the pine regenerations, and SO42– seepage was significantly higher under shelter than in the group cut. After shelter removal, neither tree species nor scenario influenced the SO42– seepage, whereas the tree species still affected NO3– seepage. We conclude that the chosen forest conversion scenario is of profound influence on the ion throughfall and seepage fluxes during the first phase of a forest conversion process.

Diverging effects of overstorey conversion scenarios on the understorey vegetation in a former coppice-with-standards forest

Conversion of historical to modern forest management regimes can have profound effects on understorey diversity and composition, because overstorey changes affect environmental conditions in the herbaceous layer. Management-driven changes (1957/1967–2005) in the overstorey of two temperate, deciduous forests generated nine conversion types in a set of 255 semi-permanent plots formerly managed as coppice-with-standards. Dominant canopy cover shifted from the shrub to the tree layer in all conversion types. Tree and shrub richness decreased significantly for most conversion types. Differences in forest structure (uneven-aged vs. even-aged), changes in litter quality and overstorey permeability for light characterised each conversion. We determined temporal changes in herb layer cover, species richness and Shannon–Wiener diversity for each conversion. We tested if herbaceous species composition for each conversion type changed between 1957/1967 and 2005 in terms of among plot variability in species composition (multivariate dispersion) and directional changes in average composition (composition shift). Differential changes in richness, cover, litter quality and shade casting ability of the overstorey were related to changes in herb layer species or ecological groups of species across conversions. Total herb layer cover increased (mainly related to Anemone nemorosa, Hyacinthoides non-scripta or Rubus fruticosus agg.), except where Beech was planted on poor soils. Richness increased where litter quality increased and decreased only on strongly shaded poor soils. Decreased/increased multivariate dispersion coincided with decreased/increased richness and Shannon–Wiener diversity. Furthermore, only conversions to even-aged stands, except for Oak on poor soils, had strong composition shifts which were reflected by an increase of indifferent/acidophilous species and species with wide amplitude. For gradual conversions to uneven-aged high forest, the edaphic changes caused by altered overstorey composition were reflected in the understorey. In the absence of incentives to reinitiate traditional management, conserving the understorey community is best achieved by a continuation of former overstorey species composition and uneven-aged high forest management. Beech plantations caused strong and negative effects, but as it is a climax species, Beech could still be used in spatiotemporal mixtures with soil improving species. Favouring or introducing the latter species can improve edaphic conditions of acid-sensitive poor soils due to their high-litter quality.

Assertiveness by Older Adults with Visual Impairment: Context Matters

Within a communication predicament of aging and disability framework, this study examined the impact of two types of contextual variation on perceptions of older adult assertiveness within problematic service encounters. Young (N = 66) and older (N = 66) participants evaluated conversational scenarios in which a visually-impaired older woman responded either passively or assertively to denial of requested assistance with reading needed information. Both older and young participants viewed the assertive older woman as more competent and as more likely to achieve her goals in future conversations than the passive older woman. The assertiveness advantage was greater in the community setting than in the hospital and for the more serious situations. Implications for education are discussed.