scholarly journals Empirical Modelling of Public Lighting Emission Functions

2021 ◽  
Vol 13 (19) ◽  
pp. 3827
Author(s):  
Brian R. Espey
Keyword(s):  
Theoretical Models ◽  
Zenith Distance ◽  
Potential Health ◽  
Empirical Modelling ◽  
Analytical Functions ◽  
Cost Of Energy ◽  
Digital Elevation ◽  
Complex Models ◽  
Closing The Loop ◽  
Inversion Techniques

Study of light at night has increased in recent decades due to the recognition of its impact on the environment, potential health concerns, as well as both the financial and carbon cost of energy waste. The advent of more extensive and improved ground-based measurements together with quantifiable satellite data has revolutionised the field, and provided data to test improved theoretical models. However, “closing the loop” and finding a detailed connection between these measurements requires knowledge of the “city emission function”, the angular distribution of upwelling radiation with zenith distance. Simplified analytical functions have been superseded by more complex models involving statistical approximation of emission sources and obstructions and inversion techniques now permit the estimation of emission functions from the observed sky brightness measurements. In this paper, we present an efficient GIS-based method to model public lighting using real-world photometric data and high-resolution digital elevation maps of obstructions such as buildings and trees at a 1 m scale. We discuss the results of this work for a sample of Irish towns as well as a city area. We also compare our results to previous emission functions as well as to observed asymmetries in emission detected by satellites such as SUOMI VIIRS.

scholarly journals Reconstructing the Dynamic Processes of the Taimali Landslide in Taiwan Using the Waveform Inversion Method

2020 ◽  
Vol 10 (17) ◽  
pp. 5872
Author(s):  
Guan-Wei Lin ◽  
Ching Hung
Keyword(s):  
Waveform Inversion ◽  
Time Function ◽  
Dynamic Processes ◽  
Inversion Method ◽  
Runout Distance ◽  
Digital Elevation ◽  
Single Station ◽  
Force Time ◽  
Elevation Model ◽  
Inversion Techniques

As a landslide occurs, seismic signals generated by the mass sliding on the slope can be recorded by seismometers nearby. Using waveform inversion techniques, we can explore the dynamic processes (e.g., sliding direction, velocity, and runout distance) of a landslide with the inverted force–time function. In this study, the point force history (PFH) inversion method was applied to the Taimali landslide in Taiwan, which was triggered by a heavy rainstorm in 2009. The inverted force–time function for the landslide revealed the complicated dynamic processes. The time series of velocity indicated three different sliding directions during the landslide. Hence, three propagating stages of the Taimali landslide were determined and were consistent with an investigation using remote sensing images and a digital elevation model of the landslide. In addition, the PFH inversion was implemented using high-quality single-station records and maintained good performance compared with the inversion by multistation records.

scholarly journals The Solubility of Two Magnetite Powders in Oxalic Acid: Applicability of Empirical Modelling

2013 ◽  
Vol 2013 ◽  
pp. 1-7
Author(s):  
Riina Salmimies ◽  
Mikko Huhtanen ◽  
Juha Kallas ◽  
Antti Häkkinen
Keyword(s):  
Linear Regression ◽  
Oxalic Acid ◽  
Multiple Linear Regression ◽  
Statistical Modelling ◽  
Theoretical Models ◽  
Quadratic Model ◽  
Empirical Modelling ◽  
Interaction Term ◽  
Effects Of Temperature ◽  
Modelling Methods

Phenomena-based models can be used in a predictive manner, but statistical modelling methods can also yield interesting findings and can serve as a tool for analysing the effects of different variables on the overall phenomenon. In addition, the generation of theoretical models can sometimes be limited due to the unideality of the studied system. Statistical modelling, in this case multiple-linear regression (MLR), was used to describe the effects of temperature and acid concentration on the dissolution of magnetite, Fe3O4 with oxalic acid. Whereas a linear model with an interaction term was sufficient in describing the dissolution of synthetic Fe3O4, a more complex full quadratic model had to be used to describe the dissolution of industrial Fe3O4 in the same conditions.

The Virtual Kidney: an eScience interface and Grid portal

2009 ◽  
Vol 367 (1896) ◽  
pp. 2141-2159 ◽  
Author(s):  
Peter J. Harris ◽  
Rajkumar Buyya ◽  
Xingchen Chu ◽  
Tom Kobialka ◽  
Ed Kazmierczak ◽  
...  
Keyword(s):  
Communication Networks ◽  
Three Dimensional ◽  
Theoretical Models ◽  
Grid Resource ◽  
Knowledge Resources ◽  
High Bandwidth ◽  
Complex Models ◽  
Simulation Results ◽  
Access To Knowledge ◽  
Parameter Values

The Virtual Kidney uses a web interface and distributed computing to provide experimental scientists and analysts with access to computational simulations and knowledge databases hosted in geographically separated laboratories. Users can explore a variety of complex models without requiring the specific programming environment in which applications have been developed. This initiative exploits high-bandwidth communication networks for collaborative research and for shared access to knowledge resources. The Virtual Kidney has been developed within a specialist community of renal scientists but is transferable to other areas of research requiring interaction between published literature and databases, theoretical models and simulations and the formulation of effective experimental designs. A web-based three-dimensional interface provides access to experimental data, a parameter database and mathematical models. A multi-scale kidney reconstruction includes blood vessels and serially sectioned nephrons. Selection of structures provides links to the database, returning parameter values and extracts from the literature. Models are run locally or remotely with a Grid resource broker managing scheduling, monitoring and visualization of simulation results and application, credential and resource allocation. Simulation results are viewed graphically or as scaled colour gradients on the Virtual Kidney structures, allowing visual and quantitative appreciation of the effects of simulated parameter changes.

Taxonomy of Q

Geophysics ◽  
2015 ◽  
Vol 80 (1) ◽  
pp. T41-T49 ◽  
Author(s):  
Igor Morozov ◽  
Amin Baharvand Ahmadi
Keyword(s):  
Spatial Resolution ◽  
Theoretical Models ◽  
Structural Formula ◽  
Quality Factors ◽  
Resolution Limit ◽  
Localized Structures ◽  
Geometric Spreading ◽  
Viscoelastic Theory ◽  
Group 3 ◽  
Inversion Techniques

The seismic quality factors [Formula: see text] used in many applications of exploration seismology are not automatically equivalent. We identified three groups of usage of the concept of a [Formula: see text]: (1) a measure of internal mechanical friction within rocks, as implied in petrophysical interpretations, (2) several types of apparent [Formula: see text] arising from attenuation measurements, and (3) axiomatic [Formula: see text] defined in the viscoelastic theory. These groups differ by their roles in the interpretation, sensitivity to model assumptions, frequency dependences, and particularly by the temporal and spatial resolution. Among all types of [Formula: see text], those that are most robust and useful for characterizing the material are also strongly limited in resolution and accuracy. For example, from spectral coherency studies, it is known that to measure a [Formula: see text] of approximately 100 with modest accuracy of 30%, measurement time intervals of about 500 ms are required. Although several inversion techniques offer models of [Formula: see text] at much higher resolution, such detailed [Formula: see text] models are usually dominated by the effects of localized structures, such as “colored” transmission across boundaries, reflectivity, or scattering. Such types of [Formula: see text] can be called “structural,” and they differ from the [Formula: see text]-factor of the medium. Detailed [Formula: see text] images are also sensitive to theoretical models such as background geometric spreading and assumptions about the frequency dependence of the [Formula: see text]. Direct association of such [Formula: see text] with material properties may be inaccurate and unreliable. Measurement of geometric spreading and averaging of the structural [Formula: see text] produce estimates of “geometric” and scattering attenuation; however, these estimates are also strongly limited in accuracy and resolution. The viscoelastic [Formula: see text] (group 3 above) heavily relies on a specific mathematical model. Despite producing detailed images, the spatial resolution of viscoelastic [Formula: see text] is inherently limited by the nature of its relation to the frequency-dependent velocity. This resolution limit is difficult to assess quantitatively.

Improving The Courses Content By Using Modelling And Simulation In Cutting Metals

2014 ◽  
Vol 1 (1) ◽  
pp. 107-110
Author(s):  
Marinela Inţă ◽  
Achim Muntean ◽  
Cristian Petrianu
Keyword(s):  
Theoretical Models ◽  
Experimental Models ◽  
Simulation Software ◽  
Production Environment ◽  
Complex Processes ◽  
Simulation Based ◽  
Complex Models ◽  
Manufacturing Technologies ◽  
Cutting Processes ◽  
2D And 3D

AbstractThe paper intends to implement the use of theoretical models and computer aided simulation based on FEM for improving the teaching of cutting metals theory for the students of Machine Manufacturing Technologies and Machine Tools. The advantage of simulation, especially animated is to transpose the normal classroom into a virtual model where the skills can be evaluated under similar realistic conditions. It helps the students to be able to face the complexity of the real complex processes inside the production environment. A review of the most important models in cutting processes shows that the majority of the researches in this field tend to replace the traditional methods of calculating the cutting data parameters based on mathematical models with new complex models. The paper tries to relieve the importance of using the FEM models and simulation software for a better understanding of the process and also for providing more accurate and more detailed information. In the case studied in this paper a series of experimental models were performed for a validation of the theoretical models created by comparing the results. The advantages of using 2D and 3D animated models in the teaching and training process are also mentioned in the paper.

scholarly journals Exploring equity in health and poverty impacts of control measures for SARS-CoV-2 in six countries

2021 ◽  
Vol 6 (5) ◽  
pp. e005521
Author(s):  
Sedona Sweeney ◽  
Theo Prudencio Juhani Capeding ◽  
Rosalind Eggo ◽  
Maryam Huda ◽  
Mark Jit ◽  
...  
Keyword(s):  
Social Protection ◽  
Economic Impacts ◽  
The Philippines ◽  
Control Measures ◽  
Income Loss ◽  
Potential Health ◽  
Complex Models ◽  
Intervention Policy ◽  
The Cost ◽  
The Impact

BackgroundPolicy makers need to be rapidly informed about the potential equity consequences of different COVID-19 strategies, alongside their broader health and economic impacts. While there are complex models to inform both potential health and macro-economic impact, there are few tools available to rapidly assess potential equity impacts of interventions.MethodsWe created an economic model to simulate the impact of lockdown measures in Pakistan, Georgia, Chile, UK, the Philippines and South Africa. We consider impact of lockdown in terms of ability to socially distance, and income loss during lockdown, and tested the impact of assumptions on social protection coverage in a scenario analysis.ResultsIn all examined countries, socioeconomic status (SES) quintiles 1–3 were disproportionately more likely to experience income loss (70% of people) and inability to socially distance (68% of people) than higher SES quintiles. Improving social protection increased the percentage of the workforce able to socially distance from 48% (33%–60%) to 66% (44%–71%). We estimate the cost of this social protection would be equivalent to an average of 0.6% gross domestic product (0.1% Pakistan–1.1% Chile).ConclusionsWe illustrate the potential for using publicly available data to rapidly assess the equity implications of social protection and non-pharmaceutical intervention policy. Social protection is likely to mitigate inequitable health and economic impacts of lockdown. Although social protection is usually targeted to the poorest, middle quintiles will likely also need support as they are most likely to suffer income losses and are disproportionately more exposed.

Analytical Electron Microscopy of Surface-Modified Ceramics

1985 ◽  
Vol 43 ◽  
pp. 276-279
Author(s):  
P. S. Sklad
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Theoretical Models ◽  
Ceramic Materials ◽  
Solute Concentration ◽  
Second Phase ◽  
Analytical Electron ◽  
Implantation Techniques ◽  
Lattice Damage ◽  
Surface Modified

Over the past several years, it has become increasingly evident that materials for proposed advanced energy systems will be required to operate at high temperatures and in aggressive environments. These constraints make structural ceramics attractive materials for these systems. However it is well known that the condition of the specimen surface of ceramic materials is often critical in controlling properties such as fracture toughness, oxidation resistance, and wear resistance. Ion implantation techniques offer the potential of overcoming some of the surface related limitations.While the effects of implantation on surface sensitive properties may be measured indpendently, it is important to understand the microstructural evolution leading to these changes. Analytical electron microscopy provides a useful tool for characterizing the microstructures produced in terms of solute concentration profiles, second phase formation, lattice damage, crystallinity of the implanted layer, and annealing behavior. Such analyses allow correlations to be made with theoretical models, property measurements, and results of complimentary techniques.

On the Relationship Between General Auditory Sensitivity and Speech Perception: An Examination of Pitch and Lexical Tone Perception in 4- to 6-Year-Old Children

2020 ◽  
Vol 63 (2) ◽  
pp. 487-498
Author(s):  
Puisan Wong ◽  
Man Wai Cheng
Keyword(s):  
Speech Perception ◽  
Theoretical Models ◽  
Developmental Trajectory ◽  
Auditory Sensitivity ◽  
Pitch Discrimination ◽  
Lexical Tone ◽  
Perceptual Training ◽  
Lexical Tones ◽  
Tone Perception ◽  
Tone Discrimination

Purpose Theoretical models and substantial research have proposed that general auditory sensitivity is a developmental foundation for speech perception and language acquisition. Nonetheless, controversies exist about the effectiveness of general auditory training in improving speech and language skills. This research investigated the relationships among general auditory sensitivity, phonemic speech perception, and word-level speech perception via the examination of pitch and lexical tone perception in children. Method Forty-eight typically developing 4- to 6-year-old Cantonese-speaking children were tested on the discrimination of the pitch patterns of lexical tones in synthetic stimuli, discrimination of naturally produced lexical tones, and identification of lexical tone in familiar words. Results The findings revealed that accurate lexical tone discrimination and identification did not necessarily entail the accurate discrimination of nonlinguistic stimuli that followed the pitch levels and pitch shapes of lexical tones. Although pitch discrimination and tone discrimination abilities were strongly correlated, accuracy in pitch discrimination was lower than that in tone discrimination, and nonspeech pitch discrimination ability did not precede linguistic tone discrimination in the developmental trajectory. Conclusions Contradicting the theoretical models, the findings of this study suggest that general auditory sensitivity and speech perception may not be causally or hierarchically related. The finding that accuracy in pitch discrimination is lower than that in tone discrimination suggests that comparable nonlinguistic auditory perceptual ability may not be necessary for accurate speech perception and language learning. The results cast doubt on the use of nonlinguistic auditory perceptual training to improve children's speech, language, and literacy abilities.

Positive Arousal Enhances the Consolidation of Item Memory

2015 ◽  
Vol 74 (2) ◽  
pp. 91-104 ◽  
Author(s):  
Bo Wang
Keyword(s):  
Episodic Memory ◽  
Memory Consolidation ◽  
Source Memory ◽  
Emotional Arousal ◽  
Theoretical Models ◽  
Memory Test ◽  
Learning Phase ◽  
Item Memory ◽  
Memory Tests ◽  
Immediate Memory

Emotional arousal induced after learning has been shown to modulate memory consolidation. However, it is unclear whether the effect of postlearning arousal can extend to different aspects of memory. This study examined the effect of postlearning positive arousal on both item memory and source memory. Participants learned a list of neutral words and took an immediate memory test. Then they watched a positive or a neutral videoclip and took delayed memory tests after either 25 minutes or 1 week had elapsed after the learning phase. In both delay conditions, positive arousal enhanced consolidation of item memory as measured by overall recognition. Furthermore, positive arousal enhanced consolidation of familiarity but not recollection. However, positive arousal appeared to have no effect on consolidation of source memory. These findings have implications for building theoretical models of the effect of emotional arousal on consolidation of episodic memory and for applying postlearning emotional arousal as a technique of memory intervention.

The Role of Distress Disclosure Tendencies in the Experience and Expression of Laboratory-Induced Sadness

2017 ◽  
Vol 38 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Jeffrey H. Kahn ◽  
Daniel W. Cox ◽  
A. Myfanwy Bakker ◽  
Julia I. O’Loughlin ◽  
Agnieszka M. Kotlarczyk
Keyword(s):  
Individual Differences ◽  
Emotional Reactivity ◽  
Subjective Experience ◽  
Negative Emotion ◽  
Theoretical Models ◽  
Laboratory Research ◽  
Emotion Words ◽  
Distress Disclosure ◽  
Computerized Text Analysis

Abstract. The benefits of talking with others about unpleasant emotions have been thoroughly investigated, but individual differences in distress disclosure tendencies have not been adequately integrated within theoretical models of emotion. The purpose of this laboratory research was to determine whether distress disclosure tendencies stem from differences in emotional reactivity or differences in emotion regulation. After completing measures of distress disclosure tendencies, social desirability, and positive and negative affect, 84 participants (74% women) were video recorded while viewing a sadness-inducing film clip. Participants completed post-film measures of affect and were then interviewed about their reactions to the film; these interviews were audio recorded for later coding and computerized text analysis. Distress disclosure tendencies were not predictive of the subjective experience of emotion, but they were positively related to facial expressions of sadness and happiness. Distress disclosure tendencies also predicted judges’ ratings of the verbal disclosure of emotion during the interview, but self-reported disclosure and use of positive and negative emotion words were not associated with distress disclosure tendencies. The authors present implications of this research for integrating individual differences in distress disclosure with models of emotion.

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